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Complex anaphora with this: variation between three written argumentative genres
No full textThe concept of complex anaphora - ‘nominal expressions referring to propositionally structured referents’ (Consten et al., 2007) - makes a useful distinction between a text-structuring function, one important to argumentative text, and the forms used to accomplish the function. Because complex anaphors often contain the demonstrative this, the contexts of all this tokens in three corpora of written argumentation – research articles, editorials, and student essays – were analysed in order to identify instances of complex anaphora. While the frequencies of pronoun use for complex anaphora were similar, the frequencies of determiner use varied, as did placement of anaphors within their host sentence, determiners appearing non-initially much more often than pronouns in all corpora, particularly editorials. Overall, there was greater variation between the patterns of use in research articles and editorials than between these and student essays
Scheduling IoT Requests to Minimize Latency in Fog Computing
No full textA Master of Science thesis in Computer Engineering by Mazin Abdelbadea Nasralla Alikarar entitled, "Scheduling IoT Requests to Minimize Latency in Fog Computing," submitted in June 2017. Thesis advisor is Dr. Raafat Aburukba and thesis co-advisor is Dr. Taha Landolsi. Soft and hard copy available.Delivering services for Internet of Things (IoT) applications that demand real-time and predictable latency is challenge. Several IoT applications require stringent latency requirements due to the interaction between the IoT devices and the physical environment through sensing and actuation. The limited capabilities of IoT devices require applications to be integrated in cloud computing and fog computing paradigms. Fog computing significantly improves on the service latency as it brings resources closer to the edge. The characteristics of both fog and cloud computing will enable the integration and interoperation of a large number of IoT devices and services in different domains. This thesis models the scheduling of IoT service requests as an optimization problem using integer programming in order to minimize the overall service request latency. The scheduling problem by nature is NP-hard, and hence, exact optimization solutions are inadequate for large size problems. Hence, this work uses the genetic algorithm (GA) as a heuristic approach to schedule the IoT requests and achieve the objective of minimizing the overall latency. The GA is tested in a dynamic simulation environment. The performance of the GA is evaluated and compared to the performance of waited-fair queuing (WFQ), priority-strict queuing (PSQ), and round robin (RR) techniques. The results show that the overall latency for the proposed approach is 21.9% to 46.6% better than the other algorithms. The proposed approach also showed significant improvement in meeting the requests deadlines by up to 31%.College of EngineeringDepartment of Computer Science and EngineeringMaster of Science in Computer Engineering (MSCoE
Treatment of Spent Caustic Using Ionic Liquids
No full textA Master of Science thesis in Chemical Engineering by Muhammad Ashraf Sabri entitled, "Treatment of Spent Caustic Using Ionic Liquids," submitted in April 2017. Thesis advisor is Dr. Taleb Hassan Ibrahim. Soft and hard copy available.Treatment of spent caustic (SC) wastes from downstream of refineries and petrochemical industries is not only complex but also highly expensive due to its content of high concentration of hazardous compounds, high pH, variations in the waste composition and the need to comply with the environmental regulations. Owing to the presence of pollutants such as sulfides, mercaptans and phenols, SC is known to be among the most difficult class of wastes to be treated and disposed. Several existing technologies have been applied to treat SC; however, they require extreme operation conditions of pressure and temperature. These methods are neither environment friendly nor cost effective. Thus, efforts are directed toward removal of specific pollutants particularly phenols, sulfides and mercaptans from SC streams in simple and environment-friendly manner. In this work, two hydrophobic ionic liquids (IL), tetrahexylammoniumdihexyl-sulfosuccinate (IL1) and trioctylmethylammonium salicylate (IL2), were used to treat industrial SC at room temperature using both bench scale batch contactor and sequential batch contactor modes. UVVis spectroscopy, gas chromatography coupled with mass spectrometry (GC-MS) and chemical oxygen demand (COD) analysis were employed for SC characterization. The chemical composition and the COD values of SC were determined before and after treatment with IL1 and IL2. The operating conditions for extraction were optimized. The results reveal that both ionic liquids have the same optimum phase ratio and initial pH of 1.0 and 1.7, respectively. The optimum contact time for IL1 and IL2 is less than 6.0 minutes and 1.0 minute, respectively. Under these optimum conditions, IL1 and IL2 are able to reduce the COD level from 6.4x104 mg/L to 63 mg/L and the phenol level from 3.2x102 mg/L to 0.032 mg/L in SC. Thiol and benzaldehyde concentrations after treatment are brought below the detection limit of the GC-MS. Thus, this work highlights the high potential of ILs as an alternative SC treatment solution compared tothe current complex industrial processes that require drastic operation conditions, use of hazardous chemicals and long contact times for SC treatment. The results of this work assure that the use of ILS for SC treatment is highly efficient, environmentally friendly, simple and novel.College of EngineeringDepartment of Chemical EngineeringMaster of Science in Chemical Engineering (MSChE
Endogenous Sanctioning Institutions and Migration Patterns: Experimental Evidence
No full textWe experimentally analyze the effect of the endogenous choice of sanctioning institutions on cooperation and migration patterns across societies. In our experiment, subjects are allocated to one of two groups, are endowed with group-specific preferences, and play a public goods game for 30 periods. Each period, subjects can move between groups and, at fixed intervals, can vote on whether to implement formal (centralized) sanctioning institutions in their group. We compare this environment to one in which only one group is exogenously endowed with sanctioning institutions. We find that subjects' ability to vote on institutions leads to (i) a more efficient partition of subjects between groups, (ii) a lower migration rate, (iii) an increase in overall payoffs, and (iv) a decrease in both inter- and intra-groups (payoff) inequality. Over time, subjects tend to vote for sanctioning institutions and contribute to the public good
Video Transmission over LTE-Unlicensed
No full textA Master of Science thesis in Electrical Engineering by Fatema Mahmood Aseeri entitled, "Video Transmission over LTE-Unlicensed," submitted in November 2017. Thesis advisor is Dr. Mohamed Hassan and thesis co-advisor is Dr. Mahmoud H. Ismail. Soft and hard copy available.The witnessed proliferation in the demand on wireless spectrum over the past years is anticipated to lead to a bandwidth scarcity problem. The situation is further aggravated by the combined increase in the demand on the delivery of high definition multimedia content over wireless networks. Recently, it was proposed to extend the LTE operation into the unlicensed spectrum (LTE-U) in an attempt to mitigate the expected scarcity problem. However, extending the operation of LTE to the unlicensed spectrum is expected to degrade the performance of other incumbent technologies, especially WiFi. While several LTE-U channel access mechanisms for enabling the coexistence of LTE with WiFi, in the unlicensed spectrum, have been proposed and evaluated, very few addressed the problem of video streaming over LTE-U. Therefore, this thesis further explores the design of efficient LTE-U channel access mechanisms from the perspective of video streaming. Specifically, we propose two channel selection schemes for video transmission over LTE-U. The first is a static channel selection scheme in which the LTE-U user equipment (UEs) are assigned to channels based on their frame type. The second one is an adaptive channel selection scheme in which UE frames are assigned to channels based on the solution to a multi-objective optimization problem that takes into account the UE's Quality of Experience (QoE) requirements while striving to minimize the interference caused to WiFi. Simulation results show that, compared to a scheme that employs an effective channel access mechanism but assigns frames to channels randomly, our proposed QoE-based channel selection scheme achieves a considerably better performance, in terms of improving the received video quality and reducing the inter-frame delay for both LTE-U and WiFi users. These results confirm the conclusion that while extending the operation of LTE-U to the unlicensed spectrum does indeed come with great benefits for LTE networks, that extension should be accompanied by smart channel selection schemes that take both the nature of the UEs data and the channel conditions into account.College of EngineeringDepartment of Electrical EngineeringMaster of Science in Electrical Engineering (MSEE
Soil Characterization Utilizing GPR Technique
No full textA Master of Science thesis in Civil Engineering by Fateh Tamam Al Kej entitled, "Soil Characterization Utilizing GPR Technique," submitted in November 2017. Thesis advisor is Dr. Magdi El-Emam and thesis co-advisors are Dr. Sherif Yehia and Dr. Nasser Qaddoumi. Soft and hard copy available.Engineering properties of soil, such as shear strength parameters, water content, degree of saturation, and permeability are essential for safe and economic design of any structure involving soil structure interactions. The invasive conventional testing methods for determining soil properties usually commence by extracting soil samples from different depths, testing them in the geotechnical lab, and comparing lab results with field test results for verification. These steps and procedures are time consuming and highly expensive, which is expected to affect the construction time and cost of any project. Noninvasive, nondestructive techniques represent a suitable alternative to the time consuming and expensive conventional site investigation procedures. However, to practically implement nondestructive techniques with acceptable confidence, a database of correlation equations need to be acquiredand well established. The work conducted in this research is a major step on a long term research project to build such database to correlate Ground Penetrating Radar (GPR) output to different soil engineering properties. GPR is an attractive tool for subsurface inspection and quality control on construction projects due to its time saving, economy, and noninvasiveness. In the current research, a group of index tests has been conducted in order to relate soil resistivity to water contents for different sandy soils. In addition, laboratory direct shear tests were conducted to measure the soil shear strength parameters at different water contents and different particle distributions. The soil dielectric constant at different water contents and different gradations is measured using the GPR technique. Index test results indicate that soil electrical resistivity is inversely proportional with the water content and compaction effort. In addition, electrical resistivity of sandy soil increases as both particle size and void ratio increase. Finally, soil resistivity increases with clay content up to certain limit and decreases thereafter. GPR test results show that, the soil dielectric constant is directly proportional to water content and inversely proportional to compaction effort. Results of index tests, lab tests, and GPR scanning test output are analyzed and correlated using regression analyses, and a 3-dimensional yet practical graph is produced for the soil types considered in this study. The proposed graph can be used to extract the soil friction angle from a rapid GPR in site scanning of any soil with similar properties.College of EngineeringDepartment of Civil EngineeringMaster of Science in Civil Engineering (MSCE
Impact of Energy Storage Systems on the Management of Fault Current at LV Network with High Penetration of Distributed Generation
No full textPenetration level of renewable energy such as solar and wind power into the grid is sharply increasing worldwide. This paper investigates the impact of the increasing level of distributed generation (DG) on the distribution network protection. Studies were commenced to mitigate the effect of small scale embedded generation (SSEG) on the system fault levels. Residential DG penetration level is modelled on the UK typical low voltage (LV) network considering the fault level stability limits. Based on penetration level of DG energy storages in the form of battery bank are determined to charge and discharge according to daily load cycle. Short circuit analysis results are compared with the UK passive network to investigate the impact of the DG on the short circuit currents at the distribution transformer. In this study, power flow from the transformer secondary is kept within limits to avoid malfunctioning of relays. The flow of reverse power in the presence of DG is confined by energy storage elements
Identification of the Uncertainty Structure to Estimate the Acoustic Release of Chemotherapeutics From Polymeric Micelles
No full textThis paper estimates the acoustic drug release from micelles after accurately identifying the underlying statistical noise characteristics in experimental data. The drug release is measured as a change in fluorescence as ultrasound is applied. First, the noise structure affecting the process dynamics and the measurement process is identified in terms of statistical covariance of the aforementioned quantities. Then, the identified covariance magnitudes are utilized to estimate the dynamics of drug release. The performance of different filters is investigated. The identified a priori knowledge is used to implement an optimal Kalman filter, a multi-hypothesis Kalman filter, and a variant of the full information estimator (moving horizon estimator) to the problem at hand. The proposed algorithms are initially deployed in a simulation environment, and then the experimental data sets are fed into the algorithms to validate their performance. Experiments span a number of ultrasonic power densities for both non-targeted and targeted polymeric micelles (the targeting being accomplished using the folate moiety). The results suggest that the proposed algorithm, the optimal Kalman filter, performs better than the other two in all tests performed
Approaches for integrated hydrogen production based on nuclear and renewable energy sources: Energy and exergy assessments of nuclear and solar energy sources in the United Arab Emirates
No full textThe United Arab Emirates (UAE) has for a long time been using oil and gas for its electricity production. However, with increasing demand in energy, rises in oil and gas prices and their future possible depletion, the UAE has adopted an ambitious plan to opt for nuclear and solar energy as its primary energy sources in the near future. The energy from a nuclear power plant is sufficiently high to back up a renewable energy source. The proposed model in this study is an integrated hydrogen production system combining both nuclear and solar energies, installed in the UAE. In this regard, a thermodynamic analysis is carried out on the nuclear and solar energy systems incorporating energy and exergy efficiencies. Overall efficiencies and the net electrical/thermal output of the power plant and system energy losses/destructions have been explained in detail. Grid network options have been explored and a smart grid system has been introduced to help better utilize solar energy. A parametric study has been conducted to determine the effect of key design and operating parameters on the system performance. Results show that the integrated system can be operated with an overall energy efficiency of 35%
