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Qatar Foundation Annual Research Forum Volume 2012 Issue 1
- Conference date: 21-23 Oct 2012
- Location: Qatar National Convention Center (QNCC), Doha, Qatar
- Volume number: 2012
- Published: 01 October 2012
251 - 300 of 469 results
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Screening for the Arab allele mutation in LDLR using molecular techniques among Bahrainis with hypercholesterolemia
Authors: Ameena Ali, Ameena Muhammed Ali, Said Shawar, Aishah Latiff and Muhammad AlsayrafiBackground: Familial hypercholesterolemia (FH) is an autosomal dominant disorder caused by defects in LDLR and leads to the elevation of blood cholesterol levels. The worldwide prevalence of the disease is 1:500 and 1 in a million for heterozygous and homozygous respectively. Recently, the Arab allele has emerged as a potential founder mutation. Objectives: The aims of this study are to develop a rapid diagnostic assay to screen for the Arab allele. Methods: Using RFLP, ARMS-PCR, and High Resolution Melt (HRM) 150 hypercholesterolemic (HC) patients from Salmaniya Medical Complex (Bahrain) were screened for the presence of the Arab allele mutation in their genomic DNA. Positive and negative controls were always run along with the samples. Results: No mutations were found among the screened volunteers and the Arab allele was not detected in the samples screened using any of the techniques described. Conclusion: Feasibility of screening using RFLP, ARMS-PCR, and HRM as a rapid diagnostic assay for the Arab allele detection was demonstrated. These assays are cost-effective in comparison to sequencing of whole LDLR gene (18 exons and 17 introns) and should be considered as a priority for any screening protocol. Ultimately, screening for FH requires the construction of all known Arab-specific mutations in a chip.
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Effect Of beta-catenin inhibition on liver cancer stem cell profile
More LessHepatocellular carcinoma (HCC) is the most common liver cancer and one of the commonest solid malignancies. High mortality rates and poor prognosis of the disease are mainly due to late diagnosis, underlying cirrhosis and resistance to chemotherapy. The risk factors of HCC include infections with hepatitis B and C viruses, along with other conditions that cause cirrhosis like: alcoholism and non-alcoholic steatohepatisis. Wnt/ß catenin signaling pathway plays a vital role in regulating the cell fate during embryogenesis and cell proliferation in adult tissues. In the absence of the Wnt ligand, beta-catenin is phosphorylated through interaction with GSK-3b, APC, axin and subsequently degraded by the ubiquitin-proteasome system. However, when the Wnt ligand binds to the receptor complex of the pathway, the destruction complex is inactivated leading to the accumulation of beta-catenin in the cytoplasm and its translocation to the nucleus where it forms complexes with TCF/LEF family that causes transcriptional activation of target genes. Recent studies suggest that cancer stem cells play a key role in liver carcinogenesis. Mutations in beta-catenin and activation of Wnt/ß-catenin signaling pathway is likely to cause abnormal proliferation and enhanced self-renewal of hepatic progenitor cells resulting in their transformation into cancer stem cells. Thus understanding the characteristics and function of liver cancer stem cells and their response to beta-catenin inhibitors is crucial to the development of novel, more effective drugs and improving patient survival. In this study we have used various drugs to target Wnt/beta-catenin signaling pathway in hepatic carcinoma cell lines. We assessed the effect of the inhibitors of beta-catenin on the expression of stem cell markers in these cell lines and will present the results of the study.
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Assessment of service quality in public and private pediatric healthcare in Qatar
Authors: Hana Yousef Al-Shouli and Mohd Nishat FaisalObjective: The purpose of this study is to assess the quality of pediatric services in public and private hospitals in Qatar. Methods: The objectives were achieved using a modified SERVQUAL scale. Data from 179 participants who visit public/private hospitals in Qatar were analyzed to find the gaps between expectations and perceptions. Results: The findings revealed that customers' expectations exceeded their perceptions, meaning that they were dissatisfied with the level of healthcare services rendered by public and private healthcare settings. The results indicated that there was a negative quality gap on each service quality scale dimension. Responsiveness and empathy variables had their highest service gaps score in public hospitals; reliability and assurance received their highest negative scores in private hospitals. Conclusions: The managers in these hospitals should work towards improving the quality of their services particularly the responsiveness and empathy dimensions.
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Using lean principles and process analysis techniques to reduce congestion in out patient departments
Authors: Fatih Mutlu, Shaligram Pokharel, Noura Gamal, Fatima Almadhoun, Dima Diab, Zina Fadel and Lama Al-SarrajBackground and Objectives: Congestion in outpatient departments (OPD) in Qatar's public hospital system is a major problem due to the demographics of the country. Despite the congestion in the general registration and assessment areas, the utilization of doctors' time is considerably low. This paradigm is propagated by (i) the inefficiencies in the appointment system, (ii) the allocation of the resources in the service design, and (iii) behavior patterns of the patients. Methods: We investigated the problem through a case study in a public hospital. First, through a careful walk-through of the patients' flow process, we identified the disruptions in the patient flows using lean principles. Simultaneously, through extensive data collection, we measured the patient flow times and resource utilization, and classified the value added- and non-value added times for the patients. Based on the observations and data collected, we propose changes for the appointment systems, patients' flow process, and allocation of resources. We benchmark the impact of our suggestions through simulation. Results: The improved solutions reduce the patient flow times by 30%. Conclusions: The patients' flow experience in public hospitals' OPDs can be significantly improved through better design of the appointment system and by eliminating wasted time in the patient flow process without investing in more resources.
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Tuberculosis beliefs, meanings, and stigmas through the eyes of Qatar's migrant workers: Survey analysis and narratives
Authors: Autumn Watts, Marwa Saleh, Rahima Sanya, Maryam Ayaz, Abhyudaya Joshi, Ali Sultan and Ziad MahfoudBackground: Tuberculosis (TB) kills nearly 3 million people and incurs at least 9 million new cases each year. While developing countries are most affected by this epidemic, migration contributes substantially to the spread of the disease. Qatar employs a vast migrant laborer workforce from TB epidemic countries, who live in high-density labor camps. Workers are grouped in the same camp rooms, and often work side by side. This puts workers at risk of developing MDR TB, with re-activation of their old TB strain or acquiring new TB infections. Objectives & Methods: This project proposed two major phases using quantitative and qualitative research methods to examine TB understandings in the migrant worker population: 1. Surveying worker perceptions of tuberculosis through widely distributed questionnaires 2. Collecting illness narratives through interviews with TB infected patients receiving treatment at the TB National Program in-patient clinic. Understanding these patients' journey with TB from the time of infection to the time of diagnosis, to life during treatment and afterward, will offer physicians, nurses and other TB personnel a better understanding of workers who are infected, or face infection, with TB. Results: -1-Survey Data Analysis Demographic and socio-economic variables of 231 participants (such as age, gender, marital status…etc) were summarized using frequency distributions. The majority of participants were between 20-29 years old and male. Almost half were Nepalese. The majority of participants said that TB is not so common or rare in their countries. Blood in cough, blood in sputum and cough were the most frequent symptoms known to participants. The majority reported the cause of bacteria was smoking. A large proportion of participants indicated that TB is preventable and treatable and it has a vaccine. -2- Three illness narratives are presented. Conclusions: Still about 1 in 4 workers have never heard about TB. Of these, most have heard about it from their own countries. Alarmingly, participants' knowledge about symptoms, causes and modes of human-to-human transmission are less than optimal. The interviews revealed several recurring themes, mainly a reluctance on the part of the patient to ask questions of the physician and health staff due to perceived social, educational, and linguistic barriers.
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The association of adiponectin gene polymorphism with gestational diabetes mellitus: The role of rs1501299 and rs2241766 variants
More LessBackground: Previous studies indicated changes of adiponectin levels during gestation. The adiponectin gene ADIPOQ is located on chromosome 3q27. The association of two single nucleotide polymorphisms (SNPs) (rs1501299 and rs2241766) in ADIPOQ gene with risk of gestational diabetes mellitus (GDM) was investigated among Arab pregnant women residing in Qatar. Methods: A case-control association study was performed on 115 pregnant women with GDM and 130 controls from Qatar. Genotypes were determined using TaqMan real time PCR assay. Fasting serum c-peptide, leptin and adiponectin levels were determined using Multiplex ELISA technique. Results: All SNPs were within the Hardy-Weinberg Equilibrium (HWE). The frequency distribution of the genotype 276 G-T (rs1501299) revealed that (40.9%), (45.6%), had GG and (53.0%), (44.0%) had GT, and (6.1%), (10.4%) had TT between GDM and control, respectively with P value= 0.261. The frequency distribution of the genotype 45T-G (rs2241766) revealed that (20.8%), (16.1%), had TT and (69.6%), (65.4%) had TG, and (9.6%), (18.5%) had GG between GDM and control, respectively with P value= 0.117. T and G alleles were the minor alleles for 276 G-T and 45T-G with a frequency of (0.11) and (0.22), respectively. Using recessive genetic model, the logistic regression analysis reveled that the Odds ratio and 95% CI was 2.14 (1.01-4.95), p=0.04 for 45T-G and was 1.79 (0.69-4.65), p=0.22 for 276 G-T. Serum c-peptide (ng/ml), and leptin (ng/ml) was significantly lower in subjects having GG versus TT+TG alleles of 45T-G with mean and SEM (7.6±1.8 Vs. 17.3 ±1.2, p= 0.002), and (21.5± 2.5 Vs. 42.1± 2.8, p=0.035). Similar significant findings were observed for TT versus TG+GG genotypes for SNP 276G-T. Adiponectin levels (µg/ml) were not significantly different in subjects having GG versus TG+TT genotypes for 45T-G and for TT versus TG+GG genotypes for 276G-T with mean and SEM (17.1± 1.8 vs. 17.2±2.3, p=0.892 and 16.5±3.24 Vs. 19.8 ±1.8, p= 0.478), respectively. Conclusion: GG carriers of 45T-G may increase the odds of getting GDM among Arab residents in Qatar. Decreased pancreatic secretory function (C-peptide) with increased adiposity (leptin) among GG carriers of 45T-G and TT carriers of 276GT may explain its roles in the development of GDM.
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Fibroblast growth factor 21 (FGF21) and diabetes-induced vascular disease
Authors: Tariq Chukir, Isra Marei, Zahra Naqvi, Navid Iqbal, Christopher Triggle and Hong DingBackground: Studying diabetes and obesity is a priority for Qatar and for the entire world. Fibroblast growth factor 21 (FGF21) is a member of the FGF superfamily that has important endocrine functions in the regulation of glucose metabolism. Elevated plasma levels of FGF21 are seen in humans with type 2 diabetes and mouse models where FGF21-resistance is associated with a reduced response to the blood glucose and insulin sensitizing actions of FGF21. There is, however, a lack of data on the effects of FGF21 on the vasculature. The objective of this study is to determine whether FGF21 and/or the FGFR1 receptor is present in endothelial cells and to determine whether FGF21 protects endothelial cells against hyperglycaemia-induced oxidative stress and uncoupling of eNOS. Methodology: RT-PCR and Western Blot techniques were used to determine the presence of FGF21/FGFR1 mRNA and protein in mouse microvascular endothelial (MMEC) and human umbilical vein endothelial (HUVEC) cell cultures. Endothelial cell cultures were treated with FGF21 to investigate the physiologic role of FGF21 in vascular tissue and to determine whether FGF21 protects the endothelial cell against glucose-induced toxicity. Western blot techniques and the dimeric/monomeric ratio were used to determine eNOS uncoupling. CM-H2DCFDA, an indicator for superoxide, was used to assess oxidative stress. Results: FGFR1 and FGF21 proteins are both expressed in MMECs exposed to high (HG) and normal (NG) glucose levels. FGFR1 levels were not changed in MMECs exposed to HG and treated with FGF21 (p=0.9; N=3) or in NG (p=0.4; N=3). For CM-H2DCFDA staining, FGF21 treated cells showed a decrease in oxidative stress (N=4). However, the eNOS dimer/monomer ratio was not affected by FGF21 in HG or NG (p=0.3; p=0.6 respectively, N=4). In HUVECs, FGFR1 is expressed in cells exposed to HG or NG (p=0.23; N3). FGF21 treatment did not affect the levels of FGFR1 in HG or NG (p=0.99; p=0.8 respectively, N=3). The eNOS dimer/monomer ratio decreased in cells exposed to HG, but was corrected following FGF21 treatment (p=0.1; N=3). Conclusion: FGF21 reduces glucose-induced oxidative stress and may , in addition to its metabolic actions, have an endothelial-vascular protective action. Supported by UREP10-034-3-009.
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Enhancing the efficiency of direct reprogramming into cardiac myocytes by defined transcription factors
Authors: Ayman Al Jurdi, Will Schachterle and Shahin RafiiAn efficient method to generate cardiac tissue from other tissues has great therapeutic potential for patients suffering from cardiovascular disease. Pluripotent stem cells, such as embryonic stem (ES) cells, and so-called induced pluripotent stem (iPS) cells can be differentiated into multiple cell types, including cardiac myocytes. However, therapeutic use of these cells has several important risks, including cancer as well as loss of differentiated cell identity and function or "drift." Transdifferentiation, the generation of cell types from other differentiated cell types, is an attractive alternative because it poses little risk of cancer and may give rise to cells whose identity is locked in. However, the direct reprogramming of adult fibroblasts into cardiac myocytes is inefficient and the transcription factors that drive this process are unknown. To circumvent these hurdles we hypothesized that fetal derived cells may be more amenable to reprogramming into cardiac myocytes with defined transcription factors. To this end, fetal derived fibroblasts and mesenchymal cells were transduced with transcription factors that have been shown to play a role in myocyte specification and maintenance, including GATA4, Mef2c, Tbx5 and Nkx2.5. To test this hypothesis, the transcription factors were cloned into lentiviral vectors, which were used to infect fibroblasts and mesenchymal cells. Infected cells were then cultured in different media. To assess the efficiency of the reprogramming, RNA was extracted from infected and uninfected cells, and quantitative RT-PCR was used to evaluate the expression levels of the transcription factors and known cardiac genes. We expected to observe higher levels of the transcription factors and cardiac markers in the infected cells relative to the uninfected cells. The results showed that the infected cells expressed higher levels of the transcription factors and a few cardiac markers relative to the uninfected cells. However, due to the small increase in the levels of only a few cardiac markers, the reprogramming was concluded to be inefficient. To make the reprogramming more efficient, other as yet unrecognized transcription factors possibly in the GATA family of transcription factors and culture conditions are currently being considered.
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Development of an expert system to automate gait data interpretation
Authors: Myriam Abi Hayla, Mohammad Khalil, John Watts and David EwinsGait analysis (GA) is often defined as the study of human walking; typically involving computerized and instrumented measurement of the movement patterns that make up walking. GA can reveal the timing and pattern of activation of muscles and joints, of body segment motions, and the forces that act on them. It can facilitate objective comparison of pathological versus normal gait and monitoring of progress in rehabilitation. However, although raw results can be printed in minutes, the clinical team may spend hours in interpreting the data. The success of this approach is limited mainly by the ability of clinicians to handle large sets of data, their expertise with respect to the biomechanics of gait, and their individual experience with the characteristics of a particular population. In addition, it is recognized that the interpretation of data varies from clinician to clinician and institution to institution which have its impact on clinical decision-making. Also, the techniques used in the interpretation of gait data often do not provide information about possible causes for gait abnormalities. Improving the efficiency of patient testing will greatly enhance the productivity of gait laboratories and improve patient care. For this reason, the focus in this project is on developing a technique for the analysis of gait data to aid clinical interpretation. A software package, also called expert system, is developed based on automating the Rancho Observational Gait Analysis Approach used to denote gait deviations. Causes related to deviations are listed and the result of additional tests that may help prove or refute any cause is also included. A report is then generated that includes all the above. The software is tested with data from a group of cerebral palsy patients to check its efficiency. Results showed that the expert system was capable in denoting deviations and overcoming a number of major challenges in gait data interpretation. However, many limitations are still present such as the need to test it on other pathologies and consider more parameters, e.g. kinetics and EMG data.
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Characterization of insulin signaling pathway in calnexin knockout cells
Authors: Samah Musa, Aleksandra Liberska, Hamid Massaeli and Nasrin MesaeliBackground: Calnexin is a lectin-like chaperone in the endoplasmic reticulum (ER) lumen, which along with calreticulin are involved in folding, maturation and trafficking of many glycoproteins. Insulin receptor and glucose transporters are among some of the proteins which are synthesized and folded in the ER. Previously, calreticulin was reported to play a role in the folding of GLUT-4 transporter as well as its stability. Furthermore, our lab reported that loss of calreticulin function results in increased insulin receptor synthesis, increased phosphorylation of Akt upon stimulation by insulin and increased glucose uptake. To date no data are available on the changes in insulin receptor pathway upon loss of calnexin chaperone. Objectives: The aim of this study is to examine changes in insulin receptor expression and insulin-mediated phosphorylation of Akt upon loss of calnexin function. Methods: Mouse embryonic fibroblast cells were serum starved overnight, then stimulated with insulin for 10 mins at 37°C. Cell lysate were prepared and Western blots with antibodies of different proteins in insulin signaling pathways were performed. Results: Our results showed a significant increase in insulin receptor expression in calnexin deficient cells. Furthermore, we observed a significant increase in the phosphorylation of Akt illustrating activation of insulin receptor pathway upon loss of calnexin function. Conclusions: In conclusion our data illustrates that loss of either of lectin like chaperones (calreticulin and calnexin) results in the activation of insulin receptor pathways via release of a negative suppressor of insulin receptor gene expression. Further research is needed to decipher the mechanism of this regulation.
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Non-invasive multiple camera calibration in highly crowded environments
Authors: Emanuel Aldea, Khurom Kiyani and Maria PetrouBackground: Very dense crowds that exceed three people per square metre present many challenges in computer vision for efficiently measuring quantities such as density and pedestrian trajectories. An accurate characterisation of such dense crowds can improve existing models and help to develop better strategies for mitigating crowd disasters. Pedestrian models used for tracking are often based on assumptions which are no longer valid in highly dense crowds, e.g. absence of occlusions. Recently, multiple camera systems with partially overlapping fields of view have been shown to offer critical advantages over other non-overlapping schemes. Objectives: We focus on overcoming the non-invasive aspect of the camera calibration, imposed by real crowded environments needed in order to accurately segment individuals. We will also underline the interdisciplinary challenges related to computer vision and real-time processing. Methods: Although there is an important amount of work devoted to multiple camera calibration, the automation of the process in specific environments remains challenging. In dense crowds, such as in Mecca, access to the site for calibration purposes or for adding support visual features is impossible. Moreover, the supervising role of the user for calibration scenarios is very important, and cumbersome for large camera networks. We investigate a light solution based on a coarse-to-fine estimation of the camera positions using both static and dynamic features. This highlights the necessary tradeoff between the crowd coverage, the purpose of the experiment, and the static feature distribution which is required to register the camera system properly. A more practical aspect that we underline is related to the importance of accurate time synchronization within the system in the presence of a dynamic scene. Results: We present a pilot study of the above scheme conducted at Regents Park Mosque in London on Friday when the mosque is particularly crowded. We have set up a distributed system of accurately synchronized Firewire cameras, acquiring high-resolution data at 8Hz. We will also aim to present some preliminary single camera studies of crowd flow using real-world data from the Muslim Hajj pilgrimage from 2011.
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A flexible and concurrent MapReduce programming model for shared-data applications
Authors: Fan Zhang and Qutaibah M MalluhiThe rapid growth of large data processing has meant the implementation of the MapReduce programming model as a widely accepted solution. The simple map and reduce stages have introduced convenience to programmers in order that they may quickly compose and design complex solutions for large-scale problems. Due to the ever-increasing complexity of execution logic in real-life applications, more and more MapReduce applications involve multiple correlated jobs encapsulated and executed according to a defined order. For example, a PageRank job involves two iterative MapReduce sub-jobs; the first job joins the rank and linkage table and the second one calculates the aggregated rank of each URL. Two non-iterative MapReduce sub-jobs for counting out-going URLs and assigning initial ranks are also included in the PageRank job. Besides this, MapReduce programming model lacks built-in support and optimization when the input data are shared. The performance will benefit when the shared and frequently accessed files are read from local instead of from distributed file system. This paper presents Concurrent MapReduce; a new programming model built on top of MapReduce while maintaining optimization and scheduling for big data applications that are composed of large number of shared data items. Concurrent MapReduce has three major characteristics: (1) Unlike traditional homogeneous map and reduce functions, it provides a flexible framework, which supports and manages multiple yet heterogeneous map and reduce functions. In other words, programmers are able to write many different map and reduce functions in a MapReduce job. (2) It launches multiple jobs in a task-level concurrency and a job-level concurrency manner. For job-level concurrency, the framework manages the shared data by replicating them from HDFS to the local file system to ensure data locality. For task-level concurrency, it is the programmers' responsibility to define the data to be shared. (3) We have evaluated the framework using two benchmarks: Single Source Shortest Path and String Matching. Results have demonstrated up to 4X performance speedup compared to traditional non-concurrent MapReduce.
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Track me to track us: Leveraging short range wireless technologies for enabling energy efficient Wi-Fi-based localization
Authors: Mohamed Abdellatif, Abderrahmen Mtibaa and Khaled HarrasGiven the success of outdoor tracking via GPS and the rise of real-time context-aware services, users will soon rely on applications that require higher granularity indoor localization. This need is further manifested in countries like Qatar, where various social and business activities occur indoors. Wi-Fi-based indoor localization is one of the most researched techniques due to its ubiquitous deployment and acceptable accuracy for a wide range of applications. However, we do not witness such techniques widely deployed mainly due to their high demand on energy, which is a precious commodity in mobile devices. We propose an energy-efficient indoor localization system that leverages peoples' typical group mobility patterns and short-range wireless technologies available on their devices. Our system architecture, shown in the figure, is designed to be easily integrated with existing Wi-Fi localization engines. We first utilize low-energy wireless technologies, such as Bluetooth, to detect and cluster individuals moving together. Our system then assigns a group representative to act as a designated cluster head that would be constantly tracked. The location of other group members can be inferred so long as they remain within proximity of the cluster heads. Afterwards, cluster heads continue to send the periodic received signal strength indicator (RSSI) updates, while the remaining members turn off their Wi-Fi interface relying on the cluster head to be localized. Our system is responsible for dynamically handling the merger or splitting of clusters as a result of mobility. We implement a prototype of the system, and evaluate it at scale using the QualNet simulator. Our results show that we can achieve up to 55% energy reduction with a relatively small degradation in localization accuracy averaging 2 meters. This accuracy reduction is non-impactful given the typical applications expected to leverage our system.
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Non-destructive visual pipe mapping for inspection
Authors: Peter Hansen, Brett Browning, Peter Rander and Hatem AlismailPipe inspection is a critical process in many industries, including oil and gas. Conventional practice relies on a range of Non-Destructive Testing (NDT) approaches such as ultrasonic and magnetic flux leakage methods. While these approaches can provide high accuracy wall thickness measurements, which can be used to monitor corrosion, they provide poor visualizations, and are typically unable to provide full pipe coverage. Moreover, they cannot be used to localize where in the pipe a defect is without expensive and possibly restricted sensors such as Inertial Navigation Systems. We have developed an automated vision-based approach that builds high-resolution 3D appearance maps of pipes and provides vehicle localization. These maps include both structure and appearance information, and can be used for direct metric measurement of pipe wall thickness, or as input to automatic corrosion detection algorithms. They may also be imported into 3D rendering engines to provide effective visualization of a pipe network. Our most recent system uses a wide angle of view fisheye camera which enables full pipe coverage and is sufficiently compact for practical applications. Our approach to mapping and localization builds from state-of-the-art visual odometry methods and extends them to deal with (visually) feature poor engineered environments. We present the results of this work using image datasets collected within our constructed pipe network. A range of empirical results are presented to validate the approach.
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Computational and statistical challenges with high dimensionality: A new method and efficient algorithm for feature selection in knowledge discovery
Authors: Mohammed El Anbari and Halima BensmailQatar is currently building one of the largest research infrastructures in the Middle East. In this orientation, Qatar foundation has constructed a number of universities and institutes composed of highly qualified researchers. In particular, QCRI institute is forming a scientific computing multidisciplinary group with a special interest in machine learning, data mining and bioinformatics. We are now able to address the computational and statistical needs of a variety of researchers with a vital set of services contributing to the development of Qatar. The availability of massive amounts of data and challenges from frontiers of research and development have reshaped statistical thinking, data analysis and theoretical studies. There is little doubt that high-dimensional data analysis will be the most important research topic in statistics in the 21st century. Indeed, the challenges of high-dimensionality arise in diverse fields of sciences, engineering, and humanities, ranging from genomics and health sciences to economics, finance, and machine learning and data mining. For example, in biomedical studies, huge numbers of magnetic resonance images (MRI) and functional MRI data are collected for each subject with hundreds of subjects involved. Satellite imagery has been used in natural resource discovery and agriculture, collecting thousands of high resolution images. Other examples of these kinds are plentiful in computational biology, climatology, geology and neurology among others. In all of these fields, variable selection and feature extraction are crucial for knowledge discovery. In this paper, we propose a computationally intensive method for regularization and variable selection in linear models. The method is based on penalized least squares with a penalty function that is a combination of the minimum concave penalty (MCP) and an L2 penalty on successive differences between coefficients. We call it the SF-MCP method. Extensive simulation studies and applications to large biomedical datasets (leukemia and glioblastoma cancers, diabetes, proteomics and metabolomics data sets) show that our approach outperforms its competitors in terms of prediction of errors and identification of relevant genes that are responsible of some lethal diseases.
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Hybrid pronunciation modeling for Arabic large vocabulary speech recognition
Authors: Mohamed Elmahdy, Mark Hasegawa-Johnson and Eiman MustafawiArabic is a morphologically rich language. This morphological complexity results in a high out-of-vocabulary rate. That is why a lookup table for pronunciation modeling is not efficient for large vocabulary tasks. In previous research, graphemic modeling was proposed by approximating pronunciation modeling to be graphemes rather than actual phonemes. In this research, we have proposed a hybrid acoustic and pronunciation modeling approach for Arabic large vocabulary speech recognition tasks. The proposed approach benefits from both phonemic and graphemic modeling techniques, where two acoustic models are fused together. The hybrid approach also benefits from both vocalized and non-vocalized Arabic resources, which is useful because the amount of non-vocalized resources is always higher than vocalized ones. Two speech recognition baseline systems were built: phonemic and graphemic. The two baseline acoustic models were combined after two independent trainings to create a hybrid model. Pronunciation modeling was also hybrid by generating graphemic variants in addition to phonemic variants. Three techniques are proposed for pronunciation modeling: Hybrid-Or, Hybrid-And, and Hybrid-Top(n). In Hybrid-Or, either graphemic or phonemic modeling is applied for any given word. In Hybrid-And, a graphemic pronunciation is always generated in addition to existing phonemic pronunciations. Hybrid-Top(n) is a mixture of Hybrid-Or and Hybrid-And by applying Hybrid-Or on the top n high frequency words. Experiments were conducted in the large vocabulary news broadcast speech domain with a vocabulary size of 250K. The proposed hybrid approach has shown a relative reduction in WER of 8.8% to 12.6% depending on pronunciation modeling settings and the supervision in the baseline systems. In large vocabulary speech domains, acoustic and pronunciation modeling is a common problem among all Arabic colloquial varieties. Thus, for future work, the proposed approach is currently being extended and evaluated with different Arabic colloquial varieties (e.g. Qatari, Egyptian, Levantine, etc.). Moreover, the proposed technique can be applied with other morphologically rich languages like Turkish, Finnish, Korean, etc. This work was funded by a grant from the Qatar National Research Fund under its National Priorities Research Program (NPRP) award number NPRP 09-410-1-069. Reported experimental work was performed at Qatar University in collaboration with University of Illinois.
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Aircraft scheduling on multiple runways
Background: Scheduling aircrafts on single or multiple runways is an important and difficult problem. This problem involves how aircrafts are sequenced on a runway and how they are assigned to runways has a significant impact on the utilization of the runways as well as on meeting the landing and departure target times. Most of the literature focuses on landing operations on a single runway as it is an easier problem to solve. Objective: This project was funded by Qatar Foundation to address the scheduling problem of both landing and departing aircrafts on multiple runways as they attempt to meet aircraft target times. The problem is further complicated when considering sequence-dependent separation times on each runway to avoid wake-vortex effects. Methods: This research project is based on a two-pronged approach. First, mathematical optimization models were developed to find optimal runway assignments and aircraft sequences on each runway. Due to the significant computational complexity of the problem, a second approach was developed to find near-optimal solution through the development of local search algorithms and metaheuristics, especially for larger problems. Results: Several optimization models were developed and the most effective one was selected to find solutions to the problem. The solution effectiveness was enhanced by developing valid inequalities to the mathematical program, which significantly reduced the computational time necessary to solve the problem. Optimal solutions were obtained for problem instances much more difficult than any accounted for in data of available literature. A scheduling index, local search algorithms and metaheuristics (Simulated Annealing and Metaheuristic for Randomized Priority Search-MetaRaPS) were also developed to solve the problem. The results show that optimal or near optimal solutions were obtained for all instances, and the value of the proposed approximate algorithms becomes more evident as the problem size increases. Conclusions: The research done in this project demonstrates that there is added value in assigning aircrafts to runways and sequencing them using more optimized methods than the most commonly used approach of first-come-first-served. This research has the potential to change how airports schedule aircrafts in order to increase the runway utilization and better meet the landing and departing target times.
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A novel and efficient relaying scheme for next generation mobile broadband communication systems
Authors: Mohammad Obaidah Shaqfeh and Hussein AlnuweiriRelaying technologies have been designated as major new enabling technologies for next generation wireless broadband systems, such as 3GPP LTE-Advanced. The practical deployment of decode-and-forward (DF) relaying technologies as supported by the current standard is based on repetition coding, meaning that the relay regenerates the same codeword generated by the source node. This scheme is suboptimal. Nevertheless, it is preferred in practice due to its simple implementation. The optimal relaying schemes called cooperative coding are difficult to construct in practice and require heavy computation load at the receiver. Therefore, they are rarely implemented despite their prospected performance gains. As a simple and practical alternative, we propose a novel relaying scheme that provides a superior performance similar to the advanced cooperative coding techniques, but it is less complex to implement. Our novel scheme is called "decode-partial-forward" (DPF) because its fundamental concept of operation is based on making the relay forwards one part of the source message such that the receiver at the destination node can rely on the direct channel with the source to obtain the other part of the message. The DPF scheme is based favorably on repetition coding and maximal ratio combining techniques, which are standardized techniques with low-complexity and low computation load. Nevertheless, our novel scheme performs very close to the optimal bounds for the supported rates over relaying links. More specifically, the increase in the supported reliable transmission rates (bits/sec) using the proposed DPF scheme may exceed 30% of the supported rates using the conventional repetition coding DF scheme. Another major advantage of our proposed scheme is that it is easy to adapt flexibly based on the channel conditions of the three links of the relay channel (source-destination, source-relay, relay-destination), by adjusting the power and rate allocation at the source and relay using simple closed-form analytic formulas. Therefore, we believe that the DPF relaying scheme is an excellent option for practical deployment in the telecommunication standards due to its simplicity, adaptability and high spectral efficiency gains.
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Adaptive multi-channel downlink assignment for overloaded spectrum-shared multi-antenna overlaid cellular networks
Authors: Redha Mahmoud Radaydeh, Mohmed-Slim Alouini and Khalid QaraqeOverlaid cellular technology has been considered as a promising candidate to enhance the capacity and extend the coverage of cellular networks, particularly indoors. The deployment of small cells (e.g. femtocells and/or picocells) in an overlaid setup is expected to reduce the operational power and to function satisfactorily with the existing cellular architecture. Among the possible deployments of small-cell access points is to manage many of them to serve specific spatial locations, while reusing the available spectrum universally. This contribution considers the aforementioned scenario with the objective to serve as many active users as possible when the available downlink spectrum is overloaded. The case study is motivated by the importance of realizing universal resource sharing in overlaid networks, while reducing the load of distributing available resources, satisfying downlink multi-channel assignment, controlling the aggregate level of interference, and maintaining desired design/operation requirements. These objectives need to be achieved in distributed manner in each spatial space with as low processing load as possible when the feedback links are capacity-limited, multiple small-cell access points can be shared, and data exchange between access points can not be coordinated. This contribution is summarized as follows. An adaptive downlink multi-channel assignment scheme when multiple co-channel and shared small-cell access points are allocated to serve active users is proposed. It is assumed that the deployed access points employ isotropic antenna arrays of arbitrary sizes, operate using the open-access strategy, and transmit on shared physical channels simultaneously. Moreover, each active user can be served by a single transmit channel per each access point at a time, and can sense the concurrent interference level associated with each transmit antenna channel non-coherently. The proposed scheme aims to identify a suitable subset of transmit channels in operating access points such that certain limits on the aggregate interference or number of serving access points are satisfied, while reducing the load of processing. The applicability of the results for some scenarios, including the identification of interference-free channels in operating access points is explained. Numerical and simulations results are shown to clarify achieved gains with the use of the proposed scheme under various operating conditions.
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OPERETTA: An optimal deployable energy efficient bandwidth aggregation system
Authors: Karim Habak, Khaled Harras and Moustafa YoussefThe widespread deployment of varying networking technologies, coupled with the exponential increase in end-user data demand has led to the proliferation of multi-interface enabled devices. To date, these interfaces are mainly utilized independently based on network availability, cost, and user choice. While researchers have focused on simultaneously leveraging these interfaces by aggregating their bandwidths, these solutions however, have faced a steep deployment barrier and only focused on maximizing throughput while overlooking the energy awareness which is critical for mobile devices. We therefore developed OPERETTA, shown in Figure1, an optimal deployable energy efficient bandwidth aggregation system for mobile users. Our system does not require modifications to applications, legacy servers, network infrastructure, or client kernel. If legacy servers choose to adopt our system, however, OPERETTA dynamically leverages this to achieve higher performance gains. OPERETTA is built as a middle-ware that is responsible for scheduling various connections and/or packets to different interfaces. This middleware estimates application and network interface characteristics and utilizes these estimates to take the most appropriate scheduling decisions. We formulate our scheduling problem as a mixed integer programming problem that has a special structure allowing it to be efficiently solved. This formulation allows users to achieve a desired throughput with minimal energy consumed. We evaluate OPERETTA via prototype implementation on the Windows OS, as well as via simulation, and compare the results to the optimal achievable throughput and energy consumption. Our results show that, with no changes to the current legacy servers, OPERETTA can achieve up to 150% enhancement in throughput as compared to the current operating systems, with no increase in energy consumption. In addition, with only 25% of the servers being OPERETTA-enabled, the system performance reaches the throughput upper-bound. We ultimately demonstrate that OPERETTA achieves the goals of being optimal, energy-efficient, as well as easily and incrementally deployable.
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CopITS: The first connected car standard-compliant platform in Qatar and the region
Authors: Fethi Filali, Hamid Menouar and Adnan Abu-DayyaGiven the clear impact that mobility has on economical and social development, the continuous increase in the number of vehicles coupled with the increase in mobility behavior of people are creating new problems and challenges that need to be holistically addressed to ensure safe, sustainable, efficient and environmentally friendly mobility systems. Cooperative Intelligent Transportations Systems (ITS) allow the transportation infrastructure, vehicles and people to be connected wirelessly (through WiFi-like technology, 3G, etc) and contribute to solve these new challenges. QMIC implemented a Connected Car (CopITS) platform that allows vehicles and road infrastructure to exchange, wirelessly, data packets enabling new cooperative applications for road safety (e.g. accident avoidance application), traffic efficiency (e.g. green light optimization application), and infotainment (e.g. media and data downloading). This platform implements the latest draft of the architecture developed within IEEE and ETSI and incorporates new enhancements in terms of communication protocols and mechanisms, which outperform existing ones by enhancing data transfer for vehicle-to-vehicle (V2V) and vehicle-to-infrastructure scenarios as well as the overall performance of the system. Simulation studies using an integrated communication/traffic simulator have been conducted to investigate important metrics like scalability, efficiency, and resilience of these mechanisms Implemented system and applications have been successfully tested in-lab and demonstrated during several events in Qatar using a real car (on-board unit) and a traffic light (roadside unit). Moreover, QMIC's Connected Car platform has been successfully tested in 2011 and 2012 Cooperative Mobility Services Interoperability tests by running all mandatory test cases, which demonstrated its interoperability with the implementations of other vendors and its conformance with the standards. We believe that QMIC's Connected Car platform is an important contribution towards putting Qatar on the world map of the "best connected countries" and being ready to host global events like the football FIFA World Cup 2022.
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Distributed load balancing through a biomimetic self organisation framework
Authors: Ali Imran, Elias Yaacoub and Adnan Abu-DayyaIn wireless cellular systems, uneven traffic load among the cells increases call blocking rates in some cells and causes low resource utilisation in others and thus degrades user satisfaction and overall performance of the cellular system. Various centralised or semi-centralised Load Balancing (LB) schemes have been proposed to cope with this time persistent problem, however, a fully distributed Self Organising (SO) LB solution is still needed for the future cellular networks. To this end, we present a novel distributed LB solution based on an analytical framework developed on the principles of nature-inspired SO systems. A novel concept of super-cell is proposed to decompose the problem of "system-wide blocking minimization" into the local sub-problems in order to enable a SO distributed solution. Performance of the proposed solution is evaluated through system level simulations for both macro cell and femto cell based systems. Numerical results show that the proposed solution can reduce the blocking in the system close to an Ideal Central Control (ICC) based LB solution. The added advantage of the proposed solution is that it does not require heavy signalling overheads.
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Performance analysis of switch-based multiuser scheduling schemes with adaptive modulation in spectrum sharing systems
Authors: Marwa Khalid Qaraqe, Mohamed Abdallah, Erchin Serpedin and Mohamed-Slim AlouiniBackground and Objective: Reliable high-speed data communication that supports multimedia application for both indoor and outdoor mobile users is a fundamental requirement for next generation wireless networks and requires a dense deployment of physically coexisting network architectures. Due to the limited spectrum availability, a novel interference-aware spectrum sharing concept is introduced where networks that suffer from congested spectrums (secondary-networks) are allowed to share the spectrum with other networks with available spectrum (primary-networks) under the condition that limited interference occurs to primary networks. The main objective is the development of multiuser access schemes for spectrum sharing systems whereby secondary users that are randomly positioned over the coverage area are allowed to share the spectrum with primary users under the condition that the interference observed at the primary receiver is below a predetermined threshold. Methods: Two scheduling schemes are proposed for selecting a user among those that satisfy the interference constraint and achieve an acceptable signal-to-noise ratio level. The first scheme selects the user that reports the best channel quality while the second is based on the concept of switched diversity where the base station scans the users in a sequential manner until an acceptable user is found. The proposed schemes operate under two power-adaptive settings that are based on the amount of interference available at the secondary transmitter. In the On/Off power setting, users transmit based on whether the interference constraint is met or not, while in the full power adaptive setting, users vary their transmission power to satisfy the interference constraint. Results: Monte Carlo simulations were used to verify the analytical results for the multiuser secondary system in terms of average spectral efficiency, system delay, and feedback. Conclusion: It is shown that scheduling users based on highest channel quality increases the average spectral efficiency, but is associated with a high feedback load. However, the switched scheduling scheme significantly decreased the feedback load but at the expense of a lower average spectral efficiency. Furthermore, it is shown that transmit power techniques increase the performance of spectrum sharing systems in terms of ASE as well as decrease system delay and feedback.
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Human centric system for oil and gas quality and pipeline infrastructure monitoring in Qatar
Authors: Adnan Nasir, Ali Riza Ekti, Khalid A Qaraqe and Erchin SerpedinBackground and Objectives: Radio frequency identification (RFID) has paved the way for a plethora of monitoring applications in the field of oil and gas. Degradation in liquefied petroleum gas (LPG)/ liquefied natural gas (LNG) quality and pipe infrastructure can be a nuisance for the oil and gas industry in Qatar. Hence, a human centric cyber-physical-system (CPS) utilizing hybrid wireless technologies including RFIDs and other sensor motes can detect and prevent such hazards. CPS technique can be used for the oil and gas sector in Qatar with customized framework architecture, event detection and decision algorithms. The objective of this research is to allow maintainers and administrators to perceive and decide on top of the monitoring system to increase the performance and efficiency of the whole monitoring application. Methods: The sensors collect the data and send it to the base station through collaborating wireless technologies. At the base station the data is processed and algorithms were run to detect an event such as presence of moisture, abnormal pressure, temperature and defects in a pipe's infrastructure health. Human interaction will help to further refine the data for possible false alarms. Mobile applications can be used by the users/administrators to send details of a perceived event directly to the base station. Results: Experiments were performed on the moisture detection in Wireless Research Laboratory in Texas A&M University at Qatar. On the similar note, other sensors can also be associated with the RFIDs and their data can be relayed to the server. A framework architecture was proposed for the human centric approach of the detection and monitoring system. Conclusion: We propose a system where these RFID active tags with the sensors such as pressure, temperature, flow, strain etc., in collaboration with other wireless technologies, are able to send information regarding the gas quality and pipe's infrastructure health. The collaboration of RFIDs and other technologies helps us to create a smart human centric monitoring system. This will enhance maintenance and event detection such as the presence of moisture or strain on pipe's structure. It will additionally assist in the automatic adjustment of the valve's and pump's properties according to the detected events.
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Identifying, implementing and recognizing Arabic accents in facial expressions for a cross-cultural robot
Authors: Amna Alzeyara, Majd Sakr and Micheline ZiadeeIn this work we attempt to understand the visual accents in Arabic facial expressions and create culture-specific facial expressions for a female multi-lingual, cross-cultural robot. This study will enable the investigation of the effect of creating such expressions on the quality of the human-robot interaction. Our work is twofold: we first identify the existence of accent variation in facial expressions across cultures, then we validate human recognition of these accents. Facial expressions embody culture and are crucial for effective communication; hence they play an important role in multi-lingual, cross-cultural human-robot interaction. Elfenbein and Ambady found that there are different accents in facial expressions, which are culture-specific, and that the differences in expressions between cultures can create misunderstandings [Elfenbein and Ambady, 2003]. Several studies compared American expressions with expressions from other cultures but none of them included Arabic facial expressions. There is no existing database for Arabic facial expressions. Consequently, we recorded videos of young Arab women narrating stories that express six emotions: happiness, sadness, surprise, fear, disgust, and disappointment. These videos were analyzed to extract Arabic accents in facial expressions. The expressions were then implemented on a 3D face model using the Facial Action Coding System (FACS). To evaluate the expressions we conducted a web-based, human-subject experiment directed at students and staff at Carnegie Mellon University in Qatar. Thirty-four participants were asked to choose the appropriate emotion for each expression and rate, on a ten-level Likert scale, the accuracy with which the expression represents the emotion. The cultural affiliation of the participants was recorded. Preliminary results show that Arabs are more likely to recognize the Arabic facial expressions over non-Arabs. To further support this conclusion the survey will be redistributed to a larger number of subjects from different cultural backgrounds and from different geographical areas.
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Extending the reach of social-based context-aware ubiquitous systems
Authors: Dania Abed Rabbou, Abderrahmen Mtibaa and Khaled HarrasThe proliferation of mobile devices equipped with communication technologies such as WiFi, 3G, and 4G, coupled with the exponential growth of online social networking, have increased the demand for social-context-aware systems. These systems leverage social information provided by users with contextual awareness, particularly location, to provide real-time personalized services. With Euromonitor International indicating a 37.7 % growth in mobile phone penetration in the past five years--ICTQatar recently reporting that each household owns 3.9 devices on average--Qatar is positioned as a strong candidate not only for the consumption of such services, but also for researching, building, and testing solutions related to context-aware system challenges. We address some of these challenges and propose pragmatic solutions. Our contributions fall into the following two categories: (i) We design and implement SCOUT, a context-aware, ubiquitous system that enables real-time mobile services by providing contextually relevant information. This information can either be generated reactively based on user request, or proactively created and disseminated to potentially interested users. Our SCOUT prototype consists of an android-based mobile client interfacing with facebook's API and a load-balancing profile-matching server that interacts with a localization engine. (ii) Since mobile users may not all experience reliable mobile-to-core connectivity due to contention, cost, or lack of connectivity, we therefore extend the reach of context-aware services to disconnected mobile users by proposing a novel communication paradigm that leverages opportunistic communication. We first send the intended information to the smallest subset of connected users deemed sufficient to reach the disconnected destinations. This subset then selectively forwards, based on social profiles, this information to nodes that are more likely to meet the destinations. Our evaluation, via simulation, shows that our algorithm achieves an improvement of 25% to 80% compared to current communication paradigms, while reducing overhead by as much as 50%. With SCOUT currently operational, and based on the simulation results, our ongoing work includes integrating our communication paradigm into the real system. We are also working on integrating real-time group recommender systems that identify groups based on user location coupled with social information to provide real-time contextual group recommendations.
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Technology intervention for the preservation of intangible cultural heritage with motion detecting technologies
By Muqeem KhanBackground: This trans-disciplinary study presents the initial outcomes of a key study undertaken to explore the role of augmented reality and motion detecting technologies in the context of Intangible Cultural Heritage (ICH) for museums-related environments. Initial prototypes are in the form of an interactive infrared camera based application for children to engage with an Aboriginal puppet, and Arabic calligraphic writings without touching any input devices. This study is unique as it tries to combine two extremes: the curation of historical intangible artifacts and their preservation through digital intervention. Objectives: This project aims to produce the following outcomes: *create a proof-of-concept ICH intelligent kinesthetic learning space; *evaluate and explore knowledge transfer opportunities of ICH afforded by peripheral games technology. The central research questions are: 1.Design: What do motion-capture and associated gaming technology experiences that are suitable for knowledge transfer of ICH in a museum situation look like? 2.Exemplified/perceived effectiveness: What is the contribution of this augmenting technology in terms of the perception of authentic and engaging learning environments? 3.Sustainability, scalability and interoperability: How can museums ensure ICH content is reusable and transferable? Methods and Results: The data will be collected and analyzed according to the differences in visitors' interactions and engagements. The data will be examined using (2 x 3 x 4) matrix triangulation strategy. The qualitative data will then be analyzed using quantitative methods such as Chi Square test and Analysis of Variance (ANOVA). The analysis will culminate the visitors' behaviors and further development of the motion-detecting prototype. It is anticipated that the results will clarify the visitors' frequency of interaction with ICH content and their length and quality of engagement with the prototype. Conclusions: Heritage-related intangible content is always restricted because of its non-physical nature and has never been fully embedded in an environment like museums and related exhibitions. The study explores alternative opportunities for knowledge transfer of ICH content that manifest with playfulness in order to elicit a deeper understanding of such intangible cultural artifacts. This study complements multiple disciplines, including heritage preservation, museum technologies and emerging interaction design.
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Interference management for multi-user cooperative relaying networks
Authors: Aymen Omri and MAZEN HASNABackground & Objectives: As the electromagnetic spectrum resource is becoming highly scarce, improving spectral efficiency is becoming extremely important for the development of future wireless communication systems. Integrating cooperative relaying techniques into wireless communication systems sheds new light on better spectral efficiency. By taking advantage of the broadcast nature of wireless communications, cooperative transmission can be used in improving communication reliability, and enhancing power and spectrum efficiency. Moreover, comparing to other emerging techniques that could achieve similar performance advantages, such as multiple-input multiple-output (MIMO) technique, cooperative communication is superior in hardware feasibility and deployment flexibility. The important advantages of cooperative communication make it one of the promising techniques for future wireless communication systems. Recently, many cooperative communication schemes have been included in different cellular standards, such as WiMAX and LTE-Advanced. However, the promised throughput and diversity gain may be lost in the presence of interferences, and hence, interference management is very important for exploiting the benefits of cooperation. This requires the need to find proper methods to prevent the interference problems, which is the main target of our current research. Methods: In this study we introduce an efficient cooperative communications scheme which maximizes the received signal-to-noise ratio (SNR) while keeping the interference levels below a certain threshold. The introduced scheme is based on two relay selection methods: max (link 2) which is based on maximizing the SNR of the second hop, and max (e2e) which aims to maximize the end-to-end SNR of the relayed link. In this method, the perfect decoding-and-forward (DF) relaying protocol is used by the relays, and the maximum ratio combining (MRC) receiver is used to combine the direct and the best selected relay links. We derive exact closed form expressions for the probability density function (PDF) of the SNR, outage probability, average capacity, and average bit error probability for the introduced cooperative schemes. Results & Conclusion: Simulations are used to validate the analytical results and an agreement is observed. The results confirm the advantage of the introduced cooperation schemes in enhancing the wireless communication system and in interference management.
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A novel wavelet-based multimodal compression scheme for joint image-signal compression
Authors: Larbi Boubchir, Tahar Brahimi, Régis Fournier and Amine Naït-AliBackground: Nowadays, by considering the important advances in multimedia and networks including telemedicine applications, the amount of information to store and/or transmit has dramatically increased over time. To overcome the limitations of transmission channels or storage systems, data compression is considered a useful tool. In general, data compression addresses the problem of reducing the amount of data required to represent any digital data including images and signals. This can be achieved by removing redundant information where the main challenge is to reduce the bit-rate while preserving a high quality of the information. Objective: This work aims to propose a new multimodal compression methodology allowing compression of jointly various data, not necessary of the same type, using only one codec. Method: The proposed joint signal-image compression methodology consists of inserting the wavelet coefficients of a decomposed signal in the details region of a wavelet transformed image at the finest scale (i.e., the highest frequency sub-bands: horizontal details, vertical details, or diagonal details) according to a spiral way. The mixture is afterwards compressed using the well-known SPIHT algorithm (Set Partitioning In Hierarchical Trees). This process is inverted by decoding the mixture, then separating the signal from the image using a separation function applied to the insertion detail sub-band area. Next, the signal and image are reconstructed using inverse wavelet transformation followed by a dequantization step. Figure 1 illustrates the corresponding compression scheme. Results: The proposed method was evaluated on medical images with biomedical signals. The experimental results obtained show that this method provides better performance compared to the basic version based on inserting the signal samples in the spatial domain of the image to the encoding phase. This is confirmed by an important obtained improvement in terms of PSNR (Peak Signal to Noise Ratio) and PRD% (Mean Square Difference).
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Geographic Information Systems as a promising area of Education and Scientific research in Qatar
More LessGeographic information systems (GIS) (also known as Geospatial information systems or Geotechnology) are computer software and hardware systems designed to capture, store and manipulate all types of geographical data, as well as analyze, manage, and display geographic information for informing decision making. Users of GIS range from communities, research institutions, environmental scientists, health organisations, land use planners, businesses, and government agencies at all levels. Numerous examples of applications of GIS are available in many different journals and are frequent topics of presentations at conferences in the natural and social sciences. For a long time, GIS has been a well-established and independent discipline throughout American and European Universities; however, there is no single University in the Arab World or even in the Middle East--as far as the author knows--that offers an undergraduate program for this important discipline. Qatar can be the pioneer in this field in the region by offering such a program through Qatar University or any higher education institute in the state. The benefits of opening such a program are numerous to be calculated. Qualified human resources in the field of GIS are in high demand not only in the region but at international level as well. The U.S. Department of Labor has designated Geotechnology (GIS) as one of the three "mega-technologies" of the 21st century—right up there with Nanotechnology and Biotechnology. Opening GIS undergraduate program in Qatar will make the state The "Kaaba" of this science in the region and will attract students from different states, which will generate scientific and financial revenue. Moreover, the host institute of this suggested program can establish an international research centre for GIS to carry out studies for the benefit of the region and beyond. Implementing such a proposal will have great impact on the Computing and Information Technology Research discipline, which is one of Qatar's core research areas.
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RFID distributed antenna systems for intelligent airport applications
Authors: Abdelmoula Bekkali and Abdullah KadriRecent developments in radio frequency identification (RFID) technology have enabled the aviation industry to benefit from its huge potential to solve issues related to baggage mishandling and to improve passenger journeys. The International Air Transport Association (IATA) estimates that more than $733 million savings by airlines alone can be realized through RFID adoption when fully implemented in the top 200 airports. Despite the obvious benefits of RFID technology in airport industry service applications, potential implementation obstacles and technical deployment challenges have to be overcome for effective, low cost and reliable passive RFID-based baggage handling and passenger asset monitoring systems. In the existing RFID system, where the RFID readers are usually placed on the conveyors, the reliable read range is often limited to a few meters. Location is then inferred from the last portal a tag is read at. In addition, the RFID tags reading accuracy varies from 97-99% in most implemented systems. This work aims at improving airport efficiency and security through real-time locating and tracking of both passengers and baggage within airport facilities. We propose to apply the concept of optical distributed antenna systems (DAS) to RFID, to develop an intelligent, adaptive, and self-organizing passive RFID real-time locating system (RTLS), suitable for deployment in airports. This system can provide reliable coverage over a wide area using only few RFID antennas. Our system will have the following characteristics and advantages. Firstly, the RFID DAS system will allow users to rapidly identify all tags and collect information with a reading tag accuracy of 100% compared to ~90-99% for the existing implemented RFID system. And thus, it can eliminate the error of manual operation. Secondly, the interrogation area or the reader coverage is greatly expanded up to 20 meters compared to 3 meters range of the existing system. Thirdly, in addition to baggage handling, the system can also track passengers and airport staff and devices. Finally, this system will provide a glimpse of the great potential returns that will support the smart airport vision.
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Everything happens somewhere: The role of geospatial analyses in government, environmental planning and research
Authors: Robert Arden Ross, Jurgen Foeken, Jeremy Jameson, Christian Strohmenger and Eric FebboWith expansion in the fields of urbanization, technical development and industrialization, Qatar faces the challenge of advancing urban and industrial development while ensuring effective safety and environmental management. Whether assessing environmental quality, the impact of a metro system, or emergency response planning, decision making relies on the integration of disparate sources of data. Geospatial referencing provides a unifying framework from which civil engineering, public policy and research decisions can be made within a web-based environment. The foundation of a geospatial reference system should be the surface geology of the country and its marine habitats. In addition to bedrock geology, the database should include features such as lineaments, drainages, land movement studies, karst features and soil types. Marine data include biota, sediment types, water quality, hydrodynamic data, and ecological sensitivity. In an arid climate, where water resources are key considerations, it is important to have a consistent geological framework for both surface and near surface geology. Accordingly, the near surface, aquifers should have a sequence stratigraphic analysis. Within a web-based infrastructure, geospatial data can be accessible to many users with access controls set by data owners and can be appropriated to user needs. Such a geodatabase mapping tool may combine 3 functions: 1) database/resource-a query tool for government, industry and the public, 2) an evaluation tool allowing the end user forward modeling/impact assessment and cause/effect analysis capability, 3) a communication tool for decision making--where results from a query may be circulated to a linked forum of specialists for consideration. The emergence of web-based, spatial referencing GIS tools shows great promise in many key aspects of public policy and research, including data storage, data analysis, and decision making. The vision is the implementation of integrated diverse multi-scale, multi-disciplinary spatial data from geological rock samples to cutting edge multi-spectral satellite imagery for use in solving complex geological, geophysical, geotechnical and environmental problems.
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Dynamic Health Level Seven Packetizer for on-the-fly integrated healthcare enterprises in disaster zones
Authors: Uvais Qidwai, Junaid Chaudhry and Malrey LeeThe advent of standards such as IEEE 11073 for device connectivity, Health Level Seven (HL7) etc., provide an assimilating platform for medical devices and seamless dataflow among modern health information systems (HIS). However, to date, these standards are either not widely accepted or lack the support of 'on-the-fly' formation of HIS in a disaster zone. In a situation where hybrid medical (standard compliant and the otherwise) devices are in operation, incomplete and ambiguous data can lead to fatal misconduct on the part of technology. In order to eliminate this problem, we propose a HL7 compliant policy engine in support of HL7 Reference Information Model (RIM). The policy engine is used for rich policy expression, vivid XML policies for HL7 compliant devices, and performance enhancement. Due to the dynamic nature of on-the-fly HIS in a disaster zone, it is very costly to manage the change and keep track of authentic HIS devices. We use Java language to extend the HL7 RIM in order to create/modify policies instead of scripting languages to overcome the complexity and interoperability.
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Distributed rendering of computer-generated images on commodity compute clusters
Authors: Othmane Bouhali and Ali SheharyarRendering of computer-generated imagery (CGI) is a very compute-intensive process. Rendering time of individual frames may vary from a few seconds to several hours depending on the scene complexity, output resolution and quality. For example, a short animation project may be about two minutes in length. It comprises 3600 frames at 30 frames per second (fps). An average rendering time for a fairly simple frame can be approximately 2 minutes, resulting in a total of 120 hours to render a simple 2-minute animation. Fortunately, animation rendering is a highly parallelizable activity as frames can be computed independently of each other. A typical animation studio has a render farm, a sophisticated cluster of special computers (nodes) used to render 3D graphics. By spreading the rendering of individual frames across hundreds of machines, the overall render time is reduced significantly. Researchers and students in a university do not usually have a render farm available. Some universities have general-purpose compute clusters but these are used mainly for running complex numerical simulations. Although rendering on these clusters is doable but it usually involves using generic queue manager (e.g. Condor, Portable Batch System PBS) rather than specialized render queue manager (e.g. DrQueue, Qube!), due to which rendering workflow becomes tedious. This paper presents a solution to create a render frame-like environment using compute-cluster resources and most importantly by using the existing render queue manager. This way, researchers and students can be presented with a rendering environment similar to any animation studio. Several benchmarking results will be presented to prove the potential benefit of this method in terms of execution time, simplicity and portability.
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A new generic approach for information extraction
Authors: Samir Elloumi, Ali Jaoua, Fethi Ferjani, Nasredine Semmar, Jihad Al-Jaam and Helmi HammamiAutomatic Information Extraction (IE) is a challenging task because it involves experts' skills and requires well developed Natural Language Processing (NLP) algorithms. Moreover, IE is domain dependent and context sensitive. In this research, we present a general learning approach that may be applied for different types of events. As a matter of fact, we observed that even if a natural language text containing a target event is apparently unstructured, it may contain a segment that we can map automatically into a structured form. Segments representing the same kind of events have a similar structure or pattern. Each pattern is composed of an ordered sequence of named entities, keywords and articulation words. Some generic named entities like organizations, persons, locations, dates, and grammatical annotations are generated by an automatic part of speech identification tool. During the learning step, each relevant segment is manually annotated with respect to the targeted entities (roles) structuring an event of the ontology. IE is processed by associating a role with a specific entity. By alignment of generic entities to specific entities, some strings of a text are automatically annotated. The alignment between patterns and a new text is not often guaranteed because of the writing styles diversity that may be detected in the news. For that reason, we have proposed soft matching between reduced formats with the objective of maximal utilization of pattern expressiveness. In several cases, this reduced format successfully allows the assignment of the same role to similar entities cited in the same side, with respect to some keywords or cue words. The experiment results are very promising since we've obtained 76.90 % as an average recognition rate.
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A fairness-based preemption algorithm for LTE-Advanced
Authors: Mehdi Khabazian, Osama Kubbar and Hossam HassaneinOne of the radio resource management (RRM) functionalities in LTE systems, call admission control (CAC) is employed to control the number of LTE bearer requests in order to maintain the quality of service (QoS) of the admitted bearers. However, no quality guarantee can be provided due to the inherently dynamic nature of wireless communication. For example, during congestion periods when several communications experience poor channel quality or high mobility, it is highly possible that the network cannot maintain its bearers' QoS requirements. Thus, preemption schemes may be employed to alleviate the situation. As a result, resource preemption mechanism and its fairness are prominent issues as they may directly affect applications' QoS in the higher layers, as well as other network attributes such as generated revenue. In general, preemption is unavoidable in two circumstances, namely, to manage the resources among bearers when the network is overloaded as a congestion control mechanism, or, to allocate a high-priority bearer request while sufficient resources are not available. In this study, we propose a preemption technique by which each an established bearer may be preempted according to its priority as well as the amount of extra allocated resources compared to its basic data rate. We define the contribution of each bearer in the preemption through a contribution metric with tuning parameters which is presented in the form of Cobb-Douglas production function. We compare the fairness of the proposed scheme with a traditional preemption scheme by means of two well-known fairness indices, i.e. Jain's index and min-max index. We also discuss its effect on bearers' blocking and dropping probability and the total generated revenue. Through a simulation approach, we conclude substantial improvements in preemption fairness when compared to the traditional approach. We discuss that the proposed scheme does not affect the main performance measurements of the network, i.e. the bearers' blocking and dropping probabilities due to congestion. We also show that the preemption contribution metric can be effectively used by the service providers to vary the total generated revenue.
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Using information extraction to dynamically create multimedia tutorials
Authors: Amal Dandashi, Jihad Mohamad Aljaam, Massoud Mwinyi, Sami Elzeiny and Ali M. JaouaBackground and Objectives: Multimedia tutorials are often useful for children with disabilities as they are better able to understand new concepts with the use of lessons that engage their senses. These tutorials should include images, sounds and videos. We propose a system to dynamically generate multimedia tutorials that can easily be customized by the instructor, with the use of domain specific information extraction. Methods: Text processing is performed with a stemming algorithm, after which formal concepts analysis is used to extract pre-specified keywords. A formal concept is represented as a hierarchical lattice structure and in this study is applied to the animal kingdom domain. Ontology-based information extraction is then performed, where multimedia elements are extracted online and mapped, by querying the Google image database. Results: The proposed system allows for automated, speedy and efficient dynamic generation of multimedia customized tutorials. Conclusions: This system automates the tutorial generation process and gives disabled children the opportunity to learn with tutorials designed to suit their intellectual needs.
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Information aspects of quantum systems
More LessInformation dynamics of different quantum systems under influence of both a phonon bath in contact with the resonator and irreversible decay of the qubits is considered. The focus of our analysis is devoted to multilevel atoms and the effects arising from the coupling to the reservoir. Even in the presence of the reservoirs, the inherent entanglement is found to be rather robust. Due to this fact, together with control of system parameters, the system may therefore be especially suited for quantum information processing. Information entropy, entropy squeezing and wehrl entropy are discussed as indicators of entanglement. Our findings also shed light on the evolution of open quantum many-body systems.
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Interference-aware random beam selection schemes for spectrum sharing systems
Authors: Mohamed Abdallah, Khalid Qaraqe and Mohamed-Slim AlouiniSpectrum sharing systems have been recently introduced to alleviate the problem of spectrum scarcity by allowing secondary unlicensed networks to share the spectrum with primary licensed networks under acceptable interference levels to the primary users. In this work, we develop interference-aware random beam selection schemes that provide enhanced performance for the secondary network under the condition that the interference observed by the receivers of the primary network is below a predetermined/acceptable value. We consider a secondary link composed of a transmitter equipped with multiple antennas and a single-antenna receiver sharing the same spectrum with a primary link composed of a single-antenna transmitter and a single-antenna receiver. The proposed schemes select a beam, among a set of power-optimized random beams, that maximizes the signal-to-interference-plus-noise ratio (SINR) of the secondary link while satisfying the primary interference constraint for different levels of feedback information describing the interference level at the primary receiver. For the proposed schemes, we develop a statistical analysis for the SINR statistics as well as the capacity and bit error rate (BER) of the secondary link.
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Implementation and evaluation of binary interval consensus on the TinyOS and TOSSIM simulator
Authors: Abderrazak Abdaoui, Tarek mohamed El-Fouly and Moez DraiefThis work considers the deployment of the binary consensus algorithm in wireless sensor networks (WSN). This algorithm is applied for the evaluation of the average measurement with the presence of a faulty/attacked node. As this algorithm has been tested theoretically, we deploy it in real life, including its distributed and routing features. In this paper, we propose the development, under simulation environment, of a distributed binary consensus algorithm. We formulate the algorithm into nesC derived from C language and running over the tiny operating system (TinyOS). The implementation was tested on sensor nodes using the TinyOSSimulator (Tossim) for a large number of nodes N and a testbed with a limited number of nodes. In performance evaluation, we considered the analysis of the average convergence time for node states to a consensus value. As in analytical results, in the simulations we applied the distributed algorithm for fully connected, paths, cycles Erdos Reny random, and starr-shaped graph topologies. Our achieved results of simulation and hardware implementations are consistent with theory.
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A neural network based lexical stress pattern classifier
Authors: Mostafa Shahin, Beena Ahmed and Kirrie BallardBackground and Objectives: In dysprosodic speech, the prosody does not match the expected intonation pattern and can result in robotic-like speech, with each syllable produced with equal stress. These errors are manifested through inconsistent lexical stress as measured by perceptual judgments and/or acoustic variables. Lexical stress is produced through variations in syllable duration, peak intensity and fundamental frequency. The presented technique automatically evaluates the unequal lexical stress patterns Strong-Weak (SW) and Week-Strong (WS) in American English continuous speech production based upon a multi-layer feed forward neural network with seven acoustic features chosen to target the lexical stress variability between two consecutive syllables. Methods: The speech corpus used in this work is the PTDB-TUG. Five females and three males were chosen to form a training set and one female and one male for testing. The CMU pronouncing dictionary with lexical stress levels marked was used to assign stress levels to each syllable in all words in the speech corpus. Lexical stress is phonetically realized through the manipulation of signal intensity, the fundamental frequency (F0) and its dynamics and the syllable/vowel duration. The nucleus duration, syllable duration, mean pitch, maximum pitch over nucleus, the peak-to-peak amplitude integral over syllable nucleus, energy mean and maximum energy over nucleus were calculated for each syllable in the collected speech. As lexical stress errors are identified by evaluating the variability between consecutive syllables in a word, we computed the pairwise variability index ("PVI") for each acoustic measure. The PVI for any acoustic feature f_i is given by: PVI_i= (f_i1-f_i2)/(( f_i1+f_i2)/2)(1), where f_i1,f_i2 are the acoustic features of the first and second syllables consecutively. A multi-layer feed forward neural network which consisted of input, hidden and output layers was used to classify the stress patterns in the words in the database. Results: The presented system had an overall accuracy of 87.6%. It correctly classified 92.4% of the SW stress patterns and 76.5% of the WS stress pattern. Conclusions: A feed-forward neural network was used to classify between the SW and WS stress patterns in American English continuous speech with overall accuracy around 87 percent.
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Accessibility research efforts needed in Qatar
Authors: David Banes and Erik ZetterströmBackground and Objectives: Mada, Qatar's Center for Assistive Technology, is a non-profit organization that strives to empower and enable people with disabilities through ICT. During late 2011 and early 2012, Mada conducted research to identify barriers to accessibility in Qatar Methods: In the survey, the key groups of respondents were identified including disabled people themselves. A combination of quantitative and qualitative methods were applied. The results were validated through the Assistive Technology Research Forum formed by Mada, which analyzed the survey results and gave additional input. These were further validated in discussions with disabled people's organizations as part of the input to the Mada future strategy. Results: The survey indicated the following major results: *People with visual impairment had both a high awareness and usage rate. *People with physical and hearing disabilities were very aware of available assistive technology but the usage rate was still low. *People with learning disabilities were not aware of available assistive technology and hence the usage rate was unsurprisingly low. Based on these findings, the AT Research Forum identified the following priority areas, which could potentially have a very high impact on barriers to accessibility in Qatar: *Arabic crowd sourced free symbol set *Improved statistical source on needs and a registry for easy user communication *Development of a free Arabic text to speech. *Wayfinding technologies for the blind incorporating enhanced technologies in emergency situations *Research into enhanced literacy amongst the deaf community when provided with text based communication solutions In addition, it was possible to highlight some crucial issues that which impeded uptake of technology, including: *The lack of accessible Arabic digital content *The limitations of current OCR technologies *The lack of useful Arabic continuous speech *Arabic word prediction and the lack of a significant available corpus Conclusions: The areas identified are fundamental projects with a very high impact in Qatar. They would best be addressed through collaboration and funding. Such collaborations bridge the private and academic sectors with specialist input from an organization supporting disabled people such as Mada.
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Energy saving mechanism in multiantenna LTE systems
Authors: Reema Imran, Zorba Nizar, Osama Kubbar and Christos VerikoukisLong Term Evolution (LTE) supports closed-loop MIMO techniques to improve its performance; however, in order to exploit the multiuser MIMO channel capabilities, the design of an efficient MAC scheme that supports MU-MIMO is essential and is still an open issue in the literature. This work proposes a novel, energy-efficient MAC scheme for LTE, which aims to achieve simultaneous downlink transmissions to multiple users through the deployment of a low-complexity beamforming technique at the physical layer. Our proposed scheme benefits from the multiuser gain of the MIMO channel and the multiplexing gain of the Multibeam Opportunistic Beamforming (MOB) technique, not only to improve the system throughput but also to provide an energy efficient wireless network. We show that our proposed scheme can provide good energy saving performance at the eNB, where the mathematical expressions for performance evaluation in terms of throughput and saved energy are also presented.
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RAFNI: Robust analysis of functional neuroimages with non-normal alpha-stable errors
Authors: Mohammed El Anbari, Halima Bensmail, Samreen Anjum and Othamne BouhaliOne of the most ambitious goals of Qatar in the next few years is to become a country based on scientific and technical researches instead of being dependent on hydrocarbons. To this end, Qatar Foundation has established a number of high caliber universities and institutes. In particular, Qatar Computing Research Institue (QCRI) is forming a scientific computing multidisciplinary group with a focus on data mining machine learning, statistical modeling and bioinformatics. We now are able to satisfy the computational statistics needs of a variety of fields, especially of biomedical researchers in Qatar. Functional magnetic resonance imaging (fMRI) is a noninvasive neuroimaging method that is widely used in cognitive neuroscience. It relies on the measurement of changes in the blood oxygenation level resulting from neural activity. The technique is widely used in cognitive neuroscience. fMRI is known to be contaminated by artifacts. Artifacts are known to have fat tailed distributions and are often skewed therefore modeling the error using a Gaussian distribution is not enough. In this paper we introduce RAFNI, an extension of AFNI, which is an fMRI open source software for the analysis of functional neuroimages. We are model the error introduced by artifacts using alpha-stable distribution. We demonstrate the applicability and efficiency of stable distributions on real fMRI. We show that the alpha-stable estimator gives better results than the OLS-based estimators.
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Model-free fuzzy intervention in biological phenomena
Authors: Hazem Nounou, Mohamed Numan Nounou, Nader Meskin and Aniruddha DattaAn important objective of modeling biological phenomena is to develop therapeutic intervention strategies to move an undesirable state of a diseased network towards a more desirable one. Such transitions can be achieved by the use of drugs to act on some genes/metabolites that affect the undesirable behavior. Biological phenomena are complex processes with nonlinear dynamics that cannot be perfectly described by a mathematical model due to several challenges such as the scarcity of biological data. Therefore, the need for model-free nonlinear intervention strategies that are capable of guiding the target variables to their desired values often arises. Addressing such a need is the main focus of this work. In many applications, fuzzy systems have been found to be very useful for parameter estimation, model development and control design of nonlinear processes. In this work, a model-free fuzzy intervention strategy (that does not require a mathematical model of the biological phenomenon) is proposed to guide the target variables of biological systems to their desired values. The proposed fuzzy intervention strategy is applied to two biological models: a glycolytic-glycogenolytic pathway model and a purine metabolism pathway model. The simulation results of the two case studies show that the fuzzy intervention schemes are able to guide the target variables to their desired values. Moreover, sensitivity analyses are conducted to study the robustness of the fuzzy intervention algorithm to variations in model parameters, and contamination due to measurement noise, in the two case studies, respectively.
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Multiscale denoising of biological data: A comparative analysis
Authors: Mohamed Nounou, Hazem Nounou, Nader Meskin and Aniruddha DattaWith the advancements in computing and sensing technologies, large amounts of data are collected from various biological systems. These data are a rich source of information about the biological systems they represent. For example, time-series metabolic data can be used to construct dynamic genetic regulatory network models, which can be used not only to better understand the interactions among different genes inside a cell, but also to design intervention strategies that can cure or manage major diseases. Also, copy number data can be used to determine the locations and extent of aberrations in chromosome sequences which are associated with many diseases such as cancer. Unfortunately, measured biological data are usually contaminated with errors that mask the important features in the data. Therefore, noisy biological measurements need to be filtered to enhance their usefulness in practice. Conventional linear low-pass filtering techniques are widely used because they are computationally efficient and can be implemented online. However, they are not effective because they operate on a single scale, meaning that they define a specific frequency, above which all features are considered noise. Real biological data possesses multiscale characteristics, i.e., may contain important features having high frequencies (such as sharp changes) or noise occurring at low frequencies (such as correlated or colored noise). Filtering such data requires multiscale filtering techniques that can account for the multiscale nature of the data. In this work, different batch as well as online multiscale filtering techniques are used to denoise biological data. These techniques include standard multiscale (SMS) filtering, online multiscale (OLMS) filtering, translation invariant (TI) filtering, and boundary corrected TI (BCTI) filtering. The performances of these techniques are demonstrated and compared to those of some conventional low-pass filters (such as the mean filter and the exponentially weighted moving average filter) using two case studies. The first case study uses simulated dynamic metabolic data, while the second case study uses real copy number data. Simulation results show that significant improvement can be achieved using multiscale filtering over conventional filtering techniques.
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A hybrid word alignment approach to build bilingual lexicons for English-Arabic machine translation
In this paper we propose a hybrid approach to align single words, compound words and idiomatic expressions from English-Arabic parallel corpora. The objective is to develop, improve and maintain automatically translation lexicons. This approach combines linguistic and statistical information in order to improve word alignment results. The linguistic improvements taken into account refer to the use of an existing bilingual lexicon, named entity recognition, grammatical tag matching and detection of syntactic dependency relation between words. Statistical information refers to the number of occurrences of repeated words, their positions in the parallel corpus and their lengths in terms of number of characters. Single-word alignment uses an existing bilingual lexicon, named entities and cognate detection and grammatical tag matching. Compound word alignment consists of establishing correspondences between the compound words of the source sentence and the compound words of the target sentences. A syntactic analysis is applied to the source and target sentences in order to extract dependency relations between words and to recognize compound words. Idiomatic expression alignment starts with a monolingual term extraction for each of the source and target languages, which provides a list of sequences of repeated words and a list of potential translations. These sequences are represented with vectors which indicate their number of occurrences and the number of segments in which they appear. Then, translation relations between the source and target expressions are evaluated with a distance metric. We have evaluated the single and multiword expression aligners using two methods: A manual evaluation of the alignment quality on 1000 pairs of English-Arabic sentences and an evaluation of the impact of this alignment on the translation quality of a machine translation system. The obtained results showed that these aligners, on the one hand, generate a translation lexicon with around 85% precision, and on the other hand, report a gain in BLEU score of 0.20 for the translation quality.
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Feature-based method for offline writer identification
Authors: Somaya Al-Maadeed and Abdelaali HassaineWriter identification consists of identifying the writer of a certain handwritten document and is of high importance in forensic document examination. Indeed, numerous cases over the years have dealt with evidence provided by handwritten documents such as wills and ransom notes. Automatic methods for writer identification can be divided into codebook-based and feature-based approaches. In codebook-based approaches, the writer is assumed to act as a stochastic generator of graphemes. The probability distribution of grapheme usage is used to distinguish between writers. Feature-based approaches compare the handwritings according to some geometrical, structural or textural features. Feature-based approaches prove to be efficient and are generally preferred when there is a limited amount of available handwriting. Therefore, we are more interested in this study in this category of approaches. Writer identification is performed by comparing a query document to a set of known documents and assigning it to the closest document in term of similarity of handwriting. This is done by extracting characterizing features from the documents including: directions, curvatures, tortuosities (or smoothness), chain codes distributions and edge based directional features. These features correspond to probability distribution functions (PDF) extracted from the handwriting images to characterize writer individuality. When matching a query document against any other document, the ¬χ2 distance between their corresponding features is computed. The smaller the distance, the more likely the two documents are written by the same writer. Therefore, the identified writer is the one of the document with the smallest distance to the query document. The writer is said to be correctly identified when the identified writer corresponds to the actual writer of the query document. The performance has been evaluated on the IAM handwriting dataset, with chain code based features generally outperforming the other features reaching 71% correct identification rate. The combination of all the features lead to 76% correct identification rate. The proposed system also won the music scores writer identification contest reaching 77% identification rate. The proposed method automatically extracts features used by forensic experts in order to identify writers of handwritten document. The results show that the method is efficient and language-independent.
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e-Security: Methodologies and approaches for the United Arab Emirates Online Business
By Fahim AkhterBackground and Objectives As e-commerce functions in a more perplex and conjoint environment than traditional businesses, a higher degree of trust is required between the users and online businesses. Uncertainties inherent to the current e-commerce environment give rise to a lack of trust and reliability in e-commerce partnerships, thereby reducing confidence and creating barriers to trade. The reason why most users and businesses in United Arab Emirates (U.A.E) are still skeptical about e-commerce involves perceived security risks associated with conducting online business. Online users consciously or subconsciously analyze the provided level of security based on their experience in order to decide whether to conduct business with the specific company or else to move on to the next company. There is a need for a better understanding of hostile environments fueled by financially-motivated, targeted cyber threats that affect consumer's decision-making behavior. The purpose of the study is to identify the factors that support the implementation and acceptance of security in e-commerce among corporations in throughout the United Arab Emirates. The study will explored the common cyber attacks that threaten the U.A.E. online businesses and will describe methodologies and approaches that can be developed to respond to those threats. Methods: A descriptive web-based survey will be adopted as an appropriate method to collect initial data from users due to its cost effectiveness, rapid turnaround, high response volume, and ability to cover a large geographical area. The combination of questions both close- and open-ended will be selected. The URL of the survey will be electronically distributed among participant using mailing lists from the Dubai chamber of commerce. Results and Conclusions: Statistics of participants from seven states of the U.A.E will be accessed and discussed here. Complete responses will be chosen out of anonymous responses for further analysis. Quantitative data will be fed into a statistical framework for researchers to understand and analyze the relationship among different responses.
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Detecting forgeries and disguised signatures in online signature verification
Authors: Abdelaali Hassaine and Somaya Al-MaadeedOnline signatures are acquired using a digital tablet which provides all the trajectories of the signature, as well as the variation in pressure with respect to time. Therefore, online signature verification achieves higher recognition rates than offline signature verification. Nowadays, forensic document examiners distinguish between forgeries, in which an impostor tries to imitate a given signature of another person and disguised signatures, in which the authentic author deliberately tries to hide his/her identity with the purpose of denial at a later stage. The disguised signatures play an important role in real forensic cases but are not considered in recent literature. In this study, we used online signatures acquired using a WACOM Intuos4 digitizing tablet with a sampling rate of 200Hz, a resolution of 2000 lines/cm and a precision of 0.25mm. The pressure information is available in 1024 levels. Online signatures contain a set of samples, each sample corresponds to the point coordinates on the digitizing tablet along with the corresponding pressure (Xt; Yt; Pt) where t corresponds to time. From those three basic signals, four other are extracted: distances, angles, speeds and angular speed. In order to compare the questioned signature with the reference signature, the differences between their corresponding features are computed at both the signal level and the histogram level. This study has been evaluated on ICDAR2009 signature verification competition dataset and a new dataset of online signatures collected at Qatar University (QU-dataset). This dataset contains signatures of genuine signatures, forgeries and disguised of 194 persons. To the extent of our knowledge, this dataset is the only one that contains disguised online signatures. The best individual performing feature for the ICDAR2009 dataset is the pressure histogram difference which reaches 8% equal error rate (EER). The pressure signal difference is the best individual performing feature for the QU-dataset (29% EER). The combination of features led to 7% EER on the ICDAR2009 dataset and 22% EER on the QU-dataset. This online signature verification system deals with both forgeries and disguised signatures. Several features have been proposed and combined using different classifiers reaching promising performance for disguised signatures detection.
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