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Optimization of Cutting Process Parameters in Inclined Drilling of Inconel 718 Using Finite Element Method and Taguchi Analysis
No full textNickel-based superalloys are famous in the demanding applications. Inconel 718 is one of the most commonly used nickel-based superalloys due to its extraordinary inherent properties. Inconel 718 is a suitable material for high temperature applications due to the properties such as anti-oxidization, high hot hardness, high creep, and fatigue strength. Drilling operation is one of the most widely used manufacturing operations in almost all industrial sectors. However, drilling operation is very complex in nature due to the presence of intricate geometry of the drill bit. In conventional drilling, cutting is performed by the combined action of the chisel edge and the two or more cutting lips. In depth analysis of the cutting process shows that chisel edge starts with an indentation at the center of the twist drill. Then away from the center, chisel edge performs orthogonal cutting with negative rake angle. Whereas, cutting action at the cutting lip is oblique in nature, and force analysis involves the use of element formulation due to involvement of radius. It is rarely found in the literature where drilling operation at different inclination angles is conducted and analyzed. The presented study numerically investigates the cutting performance of drilling operation, when operated at different inclination angles. The study revealed cutting force variation at different inclination angles due to the different tool workpiece engagement for each inclination. The magnitude of thrust force increased when inclination angle is changed from 30° to 60°. It can be linked with the higher chip load initially in this case as compared to the 30° inclination angle. The cutting temperature was affected by spindle speed (53.7%), followed by feed rate (33.31%) and inclination angle (3.44%).American University of Sharja
Digital Twin Conceptual Model within the Context of Internet of Things
No full textAs the Internet of Things (IoT) is gaining ground and becoming increasingly popular in smart city applications such as smart energy, smart buildings, smart factories, smart transportation, smart farming, and smart healthcare, the digital twin concept is evolving as complementary to its counter physical part. While an object is on the move, its operational and surrounding environmental parameters are collected by an edge computing device for local decision. A virtual replica of such object (digital twin) is based in the cloud computing platform and hosts the real-time physical object data, 2D and 3D models, historical data, and bill of materials (BOM) for further processing, analytics, and visualization. This paper proposes an end-to-end digital twin conceptual model that represents its complementary physical object from the ground to the cloud. The paper presents the proposed digital twin model's multi-layers, namely, physical, communication, virtual space, data analytic and visualization, and application as well as the overlapping security layer. The hardware and software technologies that are used in building such a model will be explained in detail. A use case will be presented to show how the layers collect, exchange, and process the physical object data from the ground to the cloud
Video Streaming over Cognitive Radio Networks
No full textA Master of Science thesis in Electrical Engineering by Maram Wahed R. Helmy entitled, “Video Streaming over Cognitive Radio Networks”, submitted in July 2020. Thesis advisors is Mohamed S. Hassan and Mahmoud H. Ismail Ibrahim. Soft copy is available (Thesis, Approval Signatures, Completion Certificate, and AUS Archives Consent Form).The exponential increase in the demand for streaming video in wireless communication is obstructed by the problem of spectrum scarcity. In an effort to mitigate this problem, cognitive radio (CR) technology was proposed as a solution since it offers a great ad- vantage to unlicensed users, also known as secondary users (SUs), by allowing them to opportunistically access the licensed primary bands. However, it is more challenging to deliver video services over CR networks not only because of the intermittent availability of the PU channels but also due to the challenges stemming from wireless channels and the quality requirements of the videos. In this work, several frameworks are proposed to stream scalable video sequences from a base station to multiple SUs over CR networks. One approach is a moments matching-based approach that enabled us to quantify the total amount of data that can be provided by the available PU channels. Specifically, a closed-from approximation for the distribution of the total amount of data available for SU over all the available PU channels during any arbitrary interval of time was obtained. The correctness of the obtained closed-form approximation is verified using simulations and numerical investigations. Another approach is employing the CR network over long-term evolution (LTE) standard platform. The objective of this work is to guarantee continuous playback at the SUs end with acceptable perceptual quality. To achieve this objective, different resource allocation schemes are introduced to adaptively assign the available radio channels to SUs while taking into considerations the quality of their assigned channels as well as their buffer occupancies. In addition, a streaming algorithm is introduced to guarantee the delivery of scalable video frames, with base and enhancement layers, within the delay constraints with priority given to the base-layer frames to guarantee the continuity of video playback. Furthermore, adaptive modulation is used based on the channel state information (CSI) as fed-back by SUs. The performance of the proposed schemes is evaluated through extensive evaluation and Monte-Carlo simulations in Matlab.College of EngineeringDepartment of Electrical EngineeringMaster of Science in Electrical Engineering (MSEE
Translation of the Resumptive Conjunctions wa and thumma in the Qur`an
No full textA Master of Arts thesis in Translation and Interpreting MATI (English/Arabic/English) by Mariam A. Ismail entitled, “Translation of the Resumptive Conjunctions Wa and Thumma in the Qur`an”, submitted in March 2020. Thesis advisor is Dr. Ahmed Ali. Soft copy is available (Thesis, Approval Signatures, Completion Certificate, and AUS Archives Consent Form).The Arabic conjunctions 'wa' and 'thumma' have particular functions, which differ from those found in the English conjunctions 'and' and 'then'. One of these functions is resumption, and the main purpose of using the resumptive 'wa' and 'thumma' in language is to show continuity in a topic. This thesis aims to identify the resumptive use of 'wa' and 'thumma' in the Qur`an and to determine the accuracy of their translations as offered by Pickthall (1930), Ghali (2003), and Shakir (1993). Six Ayahs have been selected from different surahs in the Qur`an of which three Ayahs are examples of the resumptive 'wa' and the other three are examples of the resumptive 'thumma'. The adequacy of the translations of these conjunctions under investigation is examined according to tafsiir and Newmark's 1988 model. The thesis concludes that translating the resumptive 'wa' and 'thumma' in the selected Ayahs has not been done successfully. The translators miss the functions of the resumptive 'wa' and 'thumma', hence the translations are considered out of context and fail to convey the intended message. It is therefore suggested that translators give more recognition to the function of the resumptive 'wa' and 'thumma' in the Qur`an and understand the contexts in the Qur`an, as well as they may have to consult with Arabic speaking exegetes.College of Arts and SciencesDepartment of Arabic and Translation StudiesMaster of Arts in English/Arabic/English Translation and Interpreting (MATI
Comparative Evaluation of Activated Carbon and Granulated Blast Furnace Slag in Treating Greywater
No full textA Master of Science thesis in Civil Engineering by Fatima Iqbal entitled, “Comparative Evaluation of Activated Carbon and Granulated Blast Furnace Slag in Treating Greywater”, submitted in May 2020. Thesis advisors are Dr. Kazi P. Fattah and Dr. Md. Maruf Mortula. Soft copy is available (Thesis, Approval Signatures, Completion Certificate, and AUS Archives Consent Form). Embargo expires February 25, 2021.Recycling greywater (GW) for on-site, non-potable application can reduce the load to wastewater treatment plants and stress on potable water demand for domestic water supply. However, utilization of GW requires careful treatment to ensure reduction of all contaminants to acceptable level. The conventional methods for GW treatment are expensive and energy intensive. Consequently, the search for efficient and cost-effective treatment has been on a rise in recent decades. This study investigates the effectiveness of granulated blast furnace slag (GBFS) and activated carbon (AC) in the treatment of GW from a residential building in Sharjah, United Arab Emirates. GBFS is a by product formed during the production of iron and steel-making. Since GBFS is commonly considered a waste, its utilization allows for waste reduction. Six configurations, each having a different combination of filter media, adsorbent, ultra-violet (UV) radiation and chlorine disinfection were setup at a pilot scale to assess (i) effectiveness of AC and GBFS in treating GW (ii) the impact of pre-treatment on treated water quality and (iii) the efficiency of UV and chlorine disinfection in microbial reduction. Results demonstrated that GBFS achieved higher or comparable removal efficiency for turbidity (90 – 92 %), BOD5 (76 – 86 %), COD (64.6 – 85.1 %), TSS (66.8 – 88.5 %) and TOC (80.6 – 92.7 %) in contrast to AC. GBFS displayed lower TDS removal (0 – 26 %) in contrast to AC (35.8 – 55.4 %). The addition of filter media prior to GBFS enhanced removal of TOC by 1- 3mg/l, TSS up to 99.1 % and turbidity up to 92.1 %. GBFS displayed higher reduction of TC (0.54 – 2.05 log removal) and FC (1.96 – 2.30 log removal) in contrast to AC. UV efficiency in FC and TC reduction varied in the range of 2.5 – 4.4 log removal and 0.4 – 2.7 log removal, respectively. Finally, human risk reduction performed on TC displayed GBFS combined with pre-treatment achieved lower hazard quotient (HQ) values, thereby producing reclaimed water of lower risk in comparison to AC. The study proved that it is possible to introduce GBFS as a sustainable alternative to conventional AC adsorbent for treatment of greywater at household level for non-potable use.College of EngineeringDepartment of Civil EngineeringMaster of Science in Civil Engineering (MSCE
Comparison of Whole-class Discussion and Task-based Activity: A Small-Scale Study
No full textA Master of Arts thesis in Teaching English to Speakers of Other Languages (TESOL) by Thoraya Abdullah Farzaneh entitled, “Comparison of Whole-Class Discussion and Task-Based Activity: A Small-Scale Study”, submitted in May 2020. Thesis advisor is Dr. Alessandro Benati. Soft copy is available (Thesis, Approval Signatures, Completion Certificate, and AUS Archives Consent Form).This study examined the participation patterns and effectiveness of two different sets of materials applied with two different treatments: Treatment 1 consisted of a Task-based activity; Treatment 2 used a whole-class discussion approach (Question/Answer Paradigm). The research examined the opportunities students had to venture an answer and which instructional treatment was more relevant and effective. The quantity of information students could remember immediately after instruction, one week later, and the information that emerged through the interactional formats were measured. Each procedure was carried out for approximately one hour and then participants were asked to write a summary. After a week, the same procedure was carried out to see how much information they could remember. This thesis aimed to assess the opportunities L2 learners had to express, interpret and negotiate meaning by comparing the two instructional treatments. All the interactions were transcribed. The learners’ response towards the task-based activity showed positive results and the task-based activity was considered as a better pedagogical instrument.College of Arts and SciencesDepartment of EnglishMaster of Arts in Teaching English to Speakers of Other Languages (MA TESOL
Ferromagnetic Fe-Cu Coating for Ferrous Contaminants Sensing in Aqueous Media
No full textA Master of Science thesis in Mechanical Engineering by Abdullah Abou Hewelle entitled, “Ferromagnetic Fe-Cu Coating for Ferrous Contaminants Sensing in Aqueous Media”, submitted in November 2020. Thesis advisor is Dr. Mehdi Ghommem and thesis co-advisor is Dr. Abdul Hai Al Alami. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).This work investigates the development and analysis of a novel resonant sensor for ferrous contaminations in aqueous media. Resonant sensor is a class of sensors that employ a structure vibrating at resonance. Hence, the proposed sensing device works on the principle of detecting the dynamic response of a vibrating beam resulting from the attraction of iron contaminants present in aqueous solutions to its surface. The ferromagnetic property of the Fe-Cu bimetallic alloy is utilized to capture the contaminants as it is applied as a coating layer on aluminium components. The synthesis of the ferromagnetic material and the coating process were carried out in a planetary ball mill which allows the formation of a homogenous coating layer at low operating temperatures. Microstructural characterization tests, including XRD, SEM and EDS, were performed to confirm the formation of the single-phase Fe-Cu alloy and inspect the structural features of the coating layer. A series of experiments was conducted to examine the quality of the deposition of the coating material and select the optimum synthesis process parameters. Experimental results revealed a successful deposition of a 499 nm thickness layer of the Fe-Cu alloy on the aluminum substrate after coating for 5 hours at a rotational speed of 600 rpm. The produced coated beam samples have the ability of carrying a maximum of 7 mg of iron powder. An experimental set-up, comprising a mini shaker, a laser distance sensor, and a function generator, was built and used to investigate the proposed sensing mechanisms and validate the developed mathematical continuous model for beams fully immersed in fluid media subject to base excitation. This model was also used to generate the frequency responses of the coated beam in different fluid media and predict the change in its dynamic response resulting from the added mass when exposed to iron contaminants in water showing a 0.1 Hz shift in natural frequency due to added mass equivalent to 2% of the mass of the beam.College of EngineeringDepartment of Mechanical EngineeringMaster of Science in Mechanical Engineering (MSME
Development of a Rating System for Implementing Health Impacting Features of Transport Facilities
No full textA Master of Science thesis in Civil Engineering by Bassant Essam Abdelrahman entitled, “Development of a Rating System for Implementing Health Impacting Features of Transport Facilities”, submitted in December 2020. Thesis advisor is Dr. Ghassan Abu-Lebdeh and thesis co-advisor is Dr. Salwa Beheiry. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).Transportation facilities have been recognized to strongly influence the health of urban populations. The design of transportation facilities can promote public health or impact it negatively. Several health concerns are associated with air pollution, increased urban heat, environmental noise, light pollution, water and soil pollution, social exclusion and community severance, and congestion and long commutes. Transport facilities contribute substantially to these issues, which in turn are associated with various health problems. However, transportation facilities can also promote physical activity and enhance exposure to green and blue spaces. This research aims to identify features of transportation facilities that are known to impact public health using qualitative literature analysis. These features are then used to map the impacts of transport facilities to health via the nine pathways identified in this research. The features are also used to create a methodology for rating transportation facilities with respect to health impacting features. The proposed rating system can be applied in the design of new transportation facilities or in the modification of existing ones. In addition, it can be applied to existing facilities with the aim of assessing their performance in addressing health impacts. The rating system provides an overall indication of the incorporation of health-supportive features in the rated facility. The proposed rating system is validated by an industry panel of experts. The developed rating system is composed of three rating components. The first component is the 95-potential health-promoting features of transportation facilities. The second is the number of points earned by implementing each feature. The third component is the relative importance weight of each feature, determined using the Relative Importance Index (RII). The proposed rating system was applied to 16 transportation facilities to demonstrate the rating methodology and to set thresholds for the different levels of incorporation of health impacting features. There are five levels determined in this research: very high (83% - 100%), high (76% - 83%), average (58% - 76%), low (48% - 58%), and very low (40% - 48%) levels of incorporating health impacting features.College of EngineeringDepartment of Civil EngineeringMaster of Science in Civil Engineering (MSCE
Remote Thermal Water Leakage Sensor With a Laser Communication System
No full textThe change in the temperature of an underground water pipeline and its surrounding environment caused by a leakage has been detected by a variety of devices. Among the most popular technologies are infrared cameras, distributed temperature sensing using fiber optic cables, and analog active temperature sensors. In this paper, a novel low-cost leakage detection system composed of two analog active temperature sensors is presented. The proposed system detects water leakages by comparing the readings of two analog active temperature sensors, one at the surface at a depth of 2 cm of a sand layer covering a buried water pipeline and the other is adjacent to the first sensor at the same depth in a thermally insulated portion by a polystyrene barrier. The results of the heat flow simulation developed with FEMM (Finite Element Method Magnetics) 4.2, which is free, open source, cross-platform capable of solving heat flow problems, showed that the addition of the insulation is expected to increase the difference between the readings of the sensors from 0.011 to 0.063 K (°C) when there is a leakage, and thus the addition of the insulation can be effective in making the effect of leaked water on the surface temperature more detectable. Experimental results indicated the capability of the proposed system in detecting water leakage which caused a temperature difference of 1.47 °C after 30 minutes of running a leaking water system. Furthermore, a laser communication system was built to allow for the transmission of an alarm signal from the sensing node above the underground pipeline to a master node which should have an internet connection to upload information to a cloud storage which can be accessed by different users.American University of Sharja
Selective removal of dual dyes from aqueous solutions using Metal Organic Framework (MIL-53(Al))
No full textThe adsorption process of the cationic dye Malachite Green (MG) and the anionic dye Methyl Orange (MO) onto a MOF, namely, MIL-53(Al) was studied under several experimental parameters. Batch experiments were performed to investigate the feasibility of this MOF as possible adsorbent for the removal of MG and MO from both single and binary-dye aqueous solutions. Experimental results revealed that MIL-53(Al) can quickly bind to both types of dyes with high removal efficiency of more than 95%. The effects of different parameters such as adsorbent dosage, initial concentration of dye solution, pH of the solution, and temperature on the adsorption process were examined. Adsorption kinetic data were then fitted using pseudo first-order, pseudo second-order, and elovich models, showing that pseudo second-order model had the best fit for both dyes among the other models in both single and binary-dye systems with R2>0.996. Moreover, adsorption isotherm models of Langmuir and Freundlich were studied and the isotherm data was found to be in good agreement with the Freundlich isotherm for both dyes. Thermodynamics studies of change in Gibbs free energy, enthalpy, and entropy were carried out and showed that the adsorption of both dyes was endothermic and spontaneous. The selectivity test for an equimolar binary-dye solution containing both MG and MO suggested the higher affinity of MIL-53(Al) towards MO over MG, as it reached a value of 13.58 at the optimum conditions. Finally, excellent reusability of MIL-53(Al) was shown by utilizing it for 4 cycles of adsorption-desorption with almost no reduction in the adsorption capacity, bringing about additional examination of its applicability