Qatar Foundation Annual Research Forum Volume 2013 Issue 1

Multi-phase IM drive systems are nowadays seen as a possible alternative to the three-phase drives due to their features that are especially suited for high power applications such as Oil & Gas industries, electric vehicles, traction drive, ship propulsion, robotics and mining and huge number of application. The main advantages of the multi-phase machines are higher power density with reduced volume, lower torque pulsation at higher frequency, lower dc link current harmonics and lower noise and keep going. This fault tolerance capability of the multi-phase machines makes them highly attractive for safety critical applications listed above. The trend in the drive industry is to employ sensorless topology to make the system more reliable, robust, lower hardware count, reduced cabling, reduced cost and less maintenance. The purpose of this paper is to design and develop five-phase speed sensorless induction motor drive system with inverter output LC filter. The drive system are supplied using PWM voltage source inverter and the growing switching speed of IGBTs pose additional problem of high dv/dt. The high dv/dt of the inverter output leads to several problems in the drive systems such as doubling of motor applied voltage (especially for drive with long cable), high voltage stress on motor, leakage and bearing currents leading to the bearing failure and high electromagnetic interference (EMI) etc. To mitigate these issues particularly passive filters are used. This paper focuses on using an LC filter at the output of the five-phase inverter. This paper investigate the design issues of output LC in conjunction with five-phase drive system. The LC filter causes delay and phase shift in the output voltages that affect adversely the motor control especially in sensorless vector controlled drive system. The presence of LC filter is to be incorporated in the speed estimator system. Hence the modification is necessary in the control structure. The effect of inverter output LC filter on the behavior of a sensorless vector controlled five-phase induction motor drive system investigated in this paper. Modification in the control structure and algorithm is implemented and will be reported in the full paper. The whole approach based on theoretical study, simulation verification and experimental implementation.

The United Nations (UN) estimated that over 600 million people in urban areas were exposed to dangerous levels of traffic-generated air pollutants worldwide. Currently, there is no published literature available on the levels of air pollutants, specifically NO2, due to traffic in Doha-Qatar. According to the recent reports there are more 800,000 cars registered in Qatar. This relatively high number of cars brings in problems associated with increased level of pollution. Therefore, in this study the levels of traffic related air NO2 pollution were investigated at six major intersections along C-ring road of Doha. NO2 is considered to be a marker of vehicular pollution, thus, its relationship was established with traffic volume in each intersection during December 2012 and March-April 2013. Significant differences were established between the pollutant concentration in each intersection. Higher concentrations were observed in areas with high traffic volume. Additionally, meteorological conditions were also found to influence the NO2 levels along with the topographical structure within the area. The CALINE 4 model employed during the study to estimate the effect of the measured NO2 concentration on the predicted value was only 31.12 %. The low percentage may have accounted for the uncertainties brought about the vehicle emission factor and non-availability of temporal dynamics during the time of sampling.

Accessible fresh water in rivers and lakes represent only 0.03 % of Earth's total water reservoir [1]. The protection and efficient utilization of this precious and limited resource is one of the most pressing issues in the 21st century. Today, it is estimated that 22 % percent of urban water resources is lost in the infrastructure due to leakage [2]. This article proposes a next-generation smart-sensing platform aimed at providing low-cost water-pipe inspection and leakage detection. Pipeline inspection techniques used in the traditional oil and gas industries are often not directly applicable to water systems [3]. Industry-standard pigging platforms require special launch and recovery facilities and they can not tolerate complex surface conditions caused by bio-fouling and corrosion. The current generation of water-pipe surveying instruments rely on ultrasound distance measurement which is prone to interference from road traffic, construction, and air pockets. The wavelength of ultrasound also limits its sensing accuracy [4]. Furthermore, all existing solutions requires highly trained on-site operators and thereby incurring significant deployment cost. The proposed smart-sensing platform in Figure 1 is designed to be fully autonomous, low-maintenance, and non-invasive to the existing infrastructures. The in-pipe roving sensor detects water leakage and wall-thinning and communicates this information in real-time via an acoustic-radio hybrid cellular sensor network. Portable self-powered base-stations are installed along the water-pipe at intervals of 10-100 meters and communicates with the roving sensor using a wide-band 1 MHz ultrasonic channel which, unlike electro-magnetic radio waves, can penetrate the metallic pipe wall without invasive retrofitting. The attenuation problem at this frequency range [5] is solved by the short distance between neighbouring base-stations. Channel-State-Information (CSI) is used to optimize transmitter power allocation; delays are tolerated in exchange for longer battery life. The data packets received from the roving sensor are relayed between the base-stations via the electro-magnetic radio frequency (RF) medium to the central server. The roving sensor in Figure 2 uses a compressive image sensor assisted by an acoustic transceiver to visually detect leakage sites. The image sensor's on-chip image compression (Figure 3) is facilitated by a novel Analog-to-Information architecture which allows the image to be sampled at sub-Nyquist rates with significant power savings in both image capture and processing [6]. This optic-acoustic hybrid fault detection scheme allows the image sensor to be utilized more efficiently by only waking up the image sensor when fault detection likelihood is high. The bases-station integrates a number of sensors (Figure 4) to provide complimentary pipe-line status information. Temperature [7] and humidity sensors are installed both near the pipe and at ground level. Leakage sites can be detected by observing a drop in temperature and rise in humidity in the soil near the pipe when compared to the ground level references. Zinc-oxide nano-wire gas sensors [8] is added to the sensing repertoire. All sensors on the base-station share a common ADC and analog circuit to minimized power consumption and cost. The base-station is self-powered by a solar-cell panel and a small backup battery.

With the world's current high output of industrial goods, hundreds of millions of tons of manufacturing by-products end up amassing in landfills each year. Steel-slag is not recycled to any significant degree, and even banned as a construction material in certain countries, such as Canada. Like many industrial waste residues, this limitation is mainly attributed to a lack in performance criteria permitting its economic and safe reuse. Moreover, the steel industry is a major contributor to anthropogenic CO2, and is subject to increasingly harsher regulatory codes that mandate heavier emission reductions. This project introduces a value-adding carbonation treatment that substantially enhances the waste slag's physical properties and, hence, its recyclable potential, while also presenting the added benefit of sequestering CO2. The end-use of the valorized slag as an aggregate replacement in concrete is explored. Considering that concrete is the world's most used construction material (> 9 billion tons per year), this project presents a sustainable building practice that fits within holistic environmental initiatives related to waste recycling, carbon mitigation, and resource conservation. In terms of practicality, an 8" concrete masonry block prepared in the prescribed manner will potentially sequester up to 2kg of CO2. The project ultimately seeks to demonstrate the possibility of implementing a closed loop system, for relevant industries, whereby waste streams and CO2 can be locally consumed at point source.

This paper presents a new device [TypoSoilTM] for characterizing the hydrostructural properties of the soil medium organization. It intended to simultaneously and continuously measure both the shrinkage [V(W)] and the water potential [h(W)] characteristic curves for 8 cylindrical soil samples (~100 〖"cm" 〗^"3" ) at the same time during evaporation from the saturation to dry state. No other device makes similar measurements that are crucial to research the fundamental equations of the hydrostructural behavior of soils. This device makes part of a complete chain of measurements of the hydrostructural properties of the soil medium including also the soil swelling curve [V(t)] and the unsaturated hydraulic conductivity curve [K(W)]. Twelve soil samples were prepared, and analyzed by TypoSoilTM. These samples included three replicates of reconstituted and undisturbed soil cores of two native soils in the state of Qatar, named locally "Rodah soil" and "Sabkha soil". The obtained results indicated a good procedure for the soil samples preparation, and consistent measurement of the TypoSoilTM. Minor variations were observed among SWCC and SSCC of the three replicates of each soil type showing the trustworthiness of measurement. The results will help us to make an accurate hydro-functional typology of these kinds of soils in arid countries. This information is also needed for understanding and simulating the soil hydraulic behavior under agronomical practices (irrigation), or for planning some remediation techniques of the Sabkha soils. The quality of results confirmed also the thermodynamic theory behind the exploitation of these curves to extract the hydrostructural characteristic parameters.

Cardiovascular diseases (CVDs) remain the leading cause of death worldwide, including Qatar. Hypertension is one of the most common CVDs that contribute to this mortality. Cadmium is a well-known pollutant that has been suggested to be a risk factor for hypertension. However, the underlying mechanisms are still lacking. Very little is known about the effect of cadmium on the expression of vascular alpha- 1 adrenoceptors in vascular smooth muscle cells (VSMCs). This study was therefore undertaken to determine the effect of cadmium on the expression of vascular alpha-1 adrenergic receptors in vitro. Along with that, there are several phenotypic changes could modulate the VSMCs function and contribute to CVDs including hypertension. These changes include hypertrophy, migration and senescence. The second objective of this study was to determine the effect of cadmium on VSMCs phenotype. Human aortic smooth muscle cells (HASMCs) were incubated with different concentrations of cadmium chloride for varying durations. The results indicated that cadmium (Cd) increases the expression of alpha -1 AR in HASMCs in a concentration and time dependent manner. To determine if cadmium modulates the transcriptional activity of alpha -1 AR, cells were pre-incubated with actinomycin D, a DNA-dependent RNA synthesis inhibitor. Interestingly, the cadmium-induced alpha1 AR protein expression was abolished by actinomycin D. Moreover, this expression of alpha- 1 AR was diminished when cells were pre-incubated with H89, a protein kinase A (PKA) inhibitor. This indicates that PKA plays an important role in mediating the Cd-induced expression of alpha- 1 AR. To determine the effect of Cd on VSMCs phenotype, HASMCs were incubated with CdCl2. Our results show that cadmium induces hypertrophy, migration and senescence. Taken together, our results dissect a novel pathway employed by cadmium to increase expression of vascular alpha 1 ARs, a major player in hypertension and VSMCs phenotypic modulation. This new paradigm offers a better understanding and thus potential amelioration of pollution- related CVDs.

As part of the biodiversity surveys conducted recently in Qatar, we studied the darkling beetles of the family Tenebrionidae (Coleoptera). We have started the analyses of the geographic distribution of the species, followed by studies on systematics, genetics, and evolution of the most diversified group of Coleoptera in desert environments. We have already produced relevant new results such as the discovery of the presence of Scaurus puncticollis Solier, 1838 in Qatar, and preliminary phylogeographic analyses of the populations of Adesmia cancellata distributed across Qatar. Together with these findings, we are currently updating the check-list of Qatar beetles of the family Tenebrionidae. In addition, several species of the genus Pimelia, Thriptera, and Gonocephalum are currently under taxonomic study, and we will add new records that will be included for the first time in the Biodiversity report of insect species for Qatar. The geographic range of darkling beetles in Qatar is being expanded along with current new biodiversity surveys. This suggest that the fauna of darkling beetles of Qatar is still underestimated despite previous efforts conducted by many researchers locally (e.g., Ministry of the Environment, Qatar University, Friends of the Environmental Centre) and internationally. To document and report the actual Biodiversity Heritage of Qatar, new exhaustive field biodiversity surveys should be conducted to complete the catalogue of Tenebrionoidae for the State of Qatar. This abstract is a contribution for the Qatar Foundation Annual Research Conference (QF-ARC-2013).

Exothermic reactions that undergo uncontrolled self-heating as a result of loss of cooling lead to a thermal runaway. Such reactions can present a serious hazard in the petrochemical (e.g. polymerisation processes) and chemical industries. They can reach excessively high rates of temperature increase, either due to production of gaseous reaction products, or the boiling of reactor contents. This temperature rise in effect leads to a pressure increase higher than the process equipment is made to withstand. Since the temperature rate rapidly increases (several hundred degrees per minute), a thermal explosion may occur followed by the release of toxic and flammable gases, if there is no venting mechanism to relieve the system of the excess pressure. The heat produced by a reaction is proportional to the volume of reaction mixture, while the cooling capacity however is a function of surface area. This has larger implications for industrial scaling, and is said to be the cause of accidents involving thermal runaways as in the well-known cases of Seveso in 1976, Bhopal in 1984 and more recently the T2 Laboratories in 2007. The prediction of the consequences of a runaway reaction in term of temperature and pressure evolution in a reactor vessel requires the knowledge of the reaction kinetics, thermodynamics and fluid dynamics inside the vessel during venting. Such phenomena and their interaction are complex and still to be fully understood, especially for those reactions in which the pressure generation is totally or partially due to the production of permanent gases (gassy or hybrid systems). Moreover, they cannot be easily determined by laboratory scale experiments. Computer modeling is a growing field of research necessary to develop methods capable of predicting the onset of a runaway reaction. Also, adequate vent sizing calculation methods are widely investigated for relief vent sizing emergency actions. The work described in this poster presents a dynamic model that simulates the behavior of a gassy system, specifically the decomposition of an 80% Cumene Hydro-Peroxide solution in aryl hydrocarbon during venting. The model provides the temperature, pressure, mass inventory and conversion profiles throughout the reaction. A sensitivity study of the model was performed in order to study the effect of various parameters on the resulting behaviour of the system before and after venting. The outcomes of this model provide a deeper insight into the improvement of emergency relief systems design for hybrid and gassy systems, where significant progress is still to be made both in the experimental and modeling areas.

Depending on their physical properties, aerosols in the atmosphere can scatter and/or absorb solar radiation and thus reduce the amount of solar radiation reaching the surface. Under cloud free conditions, the extinction of the Direct Normal Irradiance (DNI) is primarily caused by aerosols in the atmosphere. DNI data in locations where ground measurements are not available can be derived or estimated using satellites. However, for areas characterized by high aerosol load like in Qatar, satellite data gives DNI values with high uncertainties related to the inaccurate determination of aerosols present on a particular day. Ceilometer devices, which are based on the Lidar (LIght Detection And Ranging) technique, when operated on a routine basis, are reliable tools for long-term observation and qualitative assessment of the vertical distribution of aerosols in the atmosphere. Indeed, ceilometer measurements combined with specific retrieval software enable the detection of the vertical structure of the atmospheric boundary layer. Based on this data, the height of aerosol layers can be determined. This study describes an analysis over Doha, Qatar (25.33° N, 51.43° E), of day-to-day variability of aerosol layer heights measured by a ceilometer around solar noon under cloudless conditions; the layer heights are compared with day-to-day variability of DNI measured at the same time and same location. Aerosol layer heights are obtained using a CL51 Vaisala ceilometer. Ground measurements of DNI are collected by a pyrheliometer mounted on a high-quality Kipp & Zonen solar radiation measurement station, equipped with a sun tracker. The results of measurements for clear sky conditions over several months during this year (2013) will be presented. The study of the relation between the daily variation of aerosol layer heights and the direct component of the solar radiation is part of the solar resource assessment project within the Qatar Environment and Energy Research Institute and represents a first insight before further investigating the correlation of ceilometer backscatter measurements with ground-measured solar radiation.

Gas-To-Liquids technology is increasingly becoming an attractive source of ultra clean fuels, such as synthetic jet fuel. However, these synthetic fuels still face challenges in acquiring certification based on their properties. The focus of our current activities revolve around the experimental measurement of physical properties of fuel blends as per the aviation industries and ASTM guidelines [1], along with statistical analysis and visualization to find optimum fuel blend compositions that meet the required standards for certification. Through a series of distinct phases and with local funding from the Qatar National Research Fund (QNRF) and Qatar Science and Technology Park (QSTP), our research team has built an extensive Fuel Characterization Laboratory at Texas A&M Qatar in order to generate significant amounts of reliable data that meet industrial standards. Our methodology is to systematically generate several series of Synthetic Paraffinic Kerosene (SPK) fuel blends and to test them for their physical properties, such as density, viscosity, heat content, freezing point and flash point, following a strict safety and quality management system. In the first testing campaign the fuel blends were made from specific classes of typical GTL products (normal-, iso- and cyclo-paraffins) where the amount of each component was varied [2]. The analysis of the data generated (Figure 1) has enabled us to map how the hydrocarbon structure of a given SPK fuel blend influences its physical properties [2]. In a recent follow-up study we have also examined and mapped the influence of a fourth component, the aromatic building block, on the fuel blend properties. Aromatics improve the fuel density, which is one of the major hurdles in certifying these synthetic fuels. Separate studies also show that aromatics improve fuel-elastomer compatibility and lubricity [3]. In these first two campaigns the blends were limited in carbon number to C10 n- & cyclo- and C12 iso- paraffins, and the C7 mono-aromatic, toluene in order to study the effects of hydrocarbon structure. To improve on the model we are extending our map to study a wider range of carbon numbers. Blends in our current study are formulated from C7 to C14 hydrocarbons, which mimic the conventional jet fuel range. It is expected that these results will improve our understanding the influence of carbon chain length on the fuel properties, which have been expanded on to investigate known problematic SPK properties such as lubricity and electrical conductivity. We will report on our findings from our latest studies including the results of the aromatics campaign (using mono- as well as di-aromatics) and the statistical analysis of these data. The results from all phases are integrated into the multidimensional visualization model that correlates the properties and compositions of fuel blends. A completed model will be a useful predictive tool to help optimize the new generation of synthetic Jet fuels. References: [1] ASTM Standard D1655, 2010, DOI: 10.1520/D1655. [2] Bohra M., et al.(2012) QF-ARF, Vol. 2012, EEPS4,. [3] Orillano, M., et al. (2012) QF-ARF Vol. 2012, EEOS2.