Parametric optimization of the femoropopliteal artery stent design based on numerical analysis

High-failure rates of Peripheral Arterial Disease (PAD) stenting were reported due to the inability of certain stent strut configuration to accommodate severe biomechanical environment of the Femoro-Popliteal Artery (FPA) such as bends, twists, and axially compresses during limb flexion. The unique of mechanical deformation environment in FPA has been considered one of main factors affecting the durability of the FPA stent and reducing the stent life. Consequently, various optimization techniques have been developed to improve the mechanical performance of the FPA stent. The present work shown that, the first-two of twelve FPA resemble stent models stent models have been selected with a net score of 3.65 Model I and, with a net score of 3.55 Model II via applying Pictorial Selection Method. Finite Element Method (FEM) of optimization study based-parameterization has been conducted for stent strut dimensions, stents were compared in terms of force-stress behavior. Multi Criteria Decision Making (MCDM) method has been utilized to identify the best combination of strut dimensions. The strut thickness parameterization results were in relation T α 1/σ (T is strut thickness) for both models with all mechanical loading modes. Moreover, the strut width parameterization results were in relation W α 1/σ (W is strut width) for both models with all mechanical loading modes. Whereas, the strut length parameterization results were in relation L α σ in case of Model I and, L α 1/σ (L is strut length) in case of Model II, under axial loads, while under three-point bending and torsion loading modes L α σ for both models, under radial compression the relations were L α 1/σ in case of Model I and, L α σ in case of Model II. The best combination of strut dimension in the thickness case was t4 = 230 µm for both models, in strut width were w3=0.180, and w4= 0.250 mm for Model I and Model II, respectively, and in strut length were l2= 1.40, and l2= 1.75 mm for Model I and Model II, respectively. In conclusions, the mathematical selection approach and the consistent mathematical approach of MCDM has been proposed, also the mechanical performance has been improved for parameterized stent models

Contextually and identity aware 5G services

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University LondonThe fifth generation (5G) mobile networks aim to be ten times faster than the existing 4G connection, whilst providing low latency, and flexibility. Hence, various alterations are planned to the existing network infrastructure to be able to reach the 5G expected performance levels. The main technologies that were used, to ensure high performance, flexible network, and efficient resource allocation, are Software Defined Network and Network Function Virtualization. As these technologies are replacing the device-based architecture with, a service-based architecture. This thesis provides a design of location database interactive web interface and interactive mobile application. The implementation of real time video streaming location server, the streaming system's performance parameters demonstrated a high level of QoS (0.07ms jitter and 9.53ms delay). In regard to experimental examination, it measured the localisation coverage, accuracy measurements and a highly scalable security solution. The localisation coverage and accuracy measurements were achieved through the mmWave and VLC link transmitters. The proposed simulated annealing algorithm aimed at data optimisation for location measurements accuracy showed results of the average location error of x and y which showed significant improvement from x= 22.5 and y=21.6 to x=11.09 and y= 11.63. The proposed indoor location security solution showed significant results, as it provides a high scalability solution using the VNF. The solution showed that it was not 100% effective, as some of the fake discover packets still reached the DHCP server. This was due to the high load of traffic passing through the network. Nonetheless, 90% of the fake DHCP discover packets never reached the DHCP server because the scripts began blocking all fake discover packets after realising it was an attack. This conveys that the proposed system was able to run successfully without crashing or overloading the controller. Overall, the main challenges facing 5G have been addressed with their proposed solutions, which showed promising results. Conclusively showing that there is a lot more space for technological advancements to support the future of mobile networks.European Union’s Horizon 2020 research program - the Internet of Radio-Light (IoRL) project H2020-ICT 761992

Study of the Effect of RCS on Radar Detection

Objectives: To study the effect of the radar cross section (RCS) area for the target on the radar operation, and to show its performance on radar detection by taking samples from the RCS. Methods/Statistical Analysis: In this paper, we tested the effect of RCS on radar detection under two features of RCS using radar lab. These features are: (i) shapes with constant area and (ii) shapes with different areas. Findings: Experimental testing of the radar delectability in order to know its capability in detecting targets under and above two features( by measuring the power of echo signal) shows that whenever the power of echo signal is high (i.e. RCS is an excellent reflector), the radar detection range is high and vice versa. Application/Improvements: This proposed approach can be used in designing the target bodies using different shapes (i.e. reflectors) to dispute the transmitted signal and to weaken it. This makes the detection of targets extremely hard

Modeling For Reduction Of Harmonics Using Inverters In Smart Grid System

The rapid growth of grid-connected PY generation resulting in the total harmonic di tot1ions (THO) due to use of PV inverter is becoming a major concern. The output voltage of the inverter is a square or a nearly sinusoidal waveform, therefore, the output voltage contain the hannonic. Harmonic contents depend on the type and typology of the inverter. Use of multilevel inverter helps to solve this problem. Several converter topologie have been used in low-voltage applications; most of the topologies are not suitable in medium-voltage applications. CHB-MLI based on OHSW-SHE is a preferred choice to solve this problem. In this inverter, the THO depends on the switching angle and modulation index. The number of levels which can be synthesized in line voltage depends on MI ince the RMS line voltage depend on these number of levels. In this research, ewton Raphson iterative method is implemented for the computation of the optimal switching angles and total hannonic distortion (THO) in 5,7,9, 11 and 13-level inverter. The switching angle are calculated offline to eliminate lower order harmonic that are more hannful and difficult to remove without filter while the fundamental output voltage I obtained as desired. The simulation modeling for the single phase and the three-phase for 5.7,9,11 and 13-level CHB-MLI is done by u ing MATLAB Simulink . The THO for pha e voltage and line voltage for three-phase output inverter i obtained from the imulation for variou values of Modeling Index (MI). Computational THDs are validated with MA TLAB simulations, and both results are in close agreement. ln addition, the values of (MI) which achieve the maximum level in line to line voltage is also computed. In CHB-MLI, number of IGBT is proportional directly to number of level. One of the important features for CHB-MLl is the ability for this type to get a high AC voltage based on cascaded DC source. In addition, SHE technique helps to eliminate the lower order harmonics in the output voltage. This reduction in the THO value for the output voltage is below the limitation set in TEEE-519 without filtering y tem. Thu , it is nece ary to investigate the ability to produce 11 kv transformer less inverter to eliminate a bulk transformer in PV farm. Parameter identification is a vital part of the medium-voltage inverter de ign process. In this project, suitable IGBTs for 5, 7, 9, II , and 13 level II kYvoltage CHB-MLI for renewable generation ystem (PY) is selected accordingly. The availability of IGBT modules in the market is considered in the selection process. The result hows the line voltage THD for 13-level is below the limitation et in IEEE-519 without filtering system. [n addition, the IGBTs for 13 level II kV CHB-MLT inverter are costed a minimum total price of IGBTs when compared with IGBTs price for 5, 7, 9, and 11level. This means in transformer less CHB-MLI type, the I 3-levcl is more suitable for II kY medium application. However, this research i limited to harmonic reduction only using CHB-MLI based on OHSW-SHE, not including filter system. Also, the elimination ofhannonic is done by calculating the optimum switching angles by using equal SDCS

A critical discourse analysis on themes, (de)legitimation and ideology in the Kurdish Globe newspaper

Language reflects the influence of socio-political powers on news production. It is loaded with positive/negative values that highlight ideological concepts represented by (de)legitimation. The concept of (de)legitimation is based on argumentation that either justifies or refutes socio-political practices employed in the Iraqi media sector. Though there are plenty of studies on the (de)legitimation process in newspaper discourse, the linguistic structures underlying this process remain difficult to be understood. Therefore, the current study aims at identifying the linguistic structures used to (de)legitimize socio-political practices and reveal hidden ideologies in newspaper discourse. This study involves critical discourse analysis (CDA) using Fairclough’s (1995a) dialectical relationship approach. The data comprises news stories on the event of American Military Forces’ (AMFs’) withdrawal from Iraq, published in the Iraqi English newspaper: The Kurdish Globe (KG). A total of six news stories issued during December 2011 were collected and organized into excerpts to be analyzed. Systemic Functional Linguistics (SFL) was also employed to analyze the linguistic structures of (de)legitimation categories which were identified using van Leeuwen’s model. The study found new themes related to the event under investigation. Additionally, the study revealed the influence of political and ideological practices on news production through language, which was used to delegitimize the event in question rather than legitimizing it. It also identified the role of personal and possessive pronouns as ideological strategy in differentiating between social groups involved in that event. This study showed that the depiction of political events and decisions in newspaper discourse is governed by the context and ideologies of media organizations. The findings implied that newspaper discourse has a significant part in shaping public opinion in favor of powerful authorities. Finally, the study conceptualized a framework for understanding comparison based on argumentation made in one discourse and within the same context

Postcolonial Gothic and the Politics of Justice: A Study in Ahmed Saadawi’s Frankenstein in Baghdad

تقوم الفكرة الرئيسة لهذه الدراسة على دراسة الإخفاقات المنهجية للحياة المعاصرة للمجتمع العراقي في أعقاب الاحتلال الأميركي ما بعد 2003. وتأتي الدراسة نقداً لمرحلة الاحتلال باستخدام مسخ فرانك شتاين والتي تبدو لحظةَ مقاومة وفشل. تُظهر الدراسة، علاوة على ذلك، كيفية تقديم عنف ما بعد الحرب قوةً غير إنسانية في فرانكن شتاين في بغداد  للكاتب احمد سعداوي مع عنف لا يمكن إيقافه حيث ان الوحش او العنف ينعش نفسه من خلال توليد المزيد من العنف وكيف تتشكل قصص العنف اليومية هذه في الغالب من حالة الفوضى. إحدى الاستنتاجات التي توصل إليها الباحث أنه في ظل الاحتلال الأمريكي، لا يمكن للناس أن يقرروا مصيرهم أو يعلنوا موقفهم. ولا يمكنهم إعلان موقفهم ضد الأمريكيين وضد دولة الإرهاب المسلح، ولا يمكنهم في نفس الوقت دعم أعمال القتل والإرهاب.  The central goal of this paper is to scrutinize the systemic failings of the contemporary moment of Iraqi government aftermath. The study comes as a critique of the colonial moment of injustice using the resurrection of Frankenstein which appears as a moment of resistance and failure. The study, furthermore, reveals how the cruelty of war is shown as a dehumanizing force in Saadawi’s Frankenstein in Baghdad with continuous violence that refreshes itself by generating more violence and how that everyday harsh stories are mostly shaped by the state of disorder under and after the occupation. It, also, shows the extent to which the monster is the representation of reality of Iraqi conditions after the 2003 US occupation. One of the conclusions the researcher has arrived at is that under the US occupation people, instead of welfare, left without a will to decide their fate. They cannot declare their position against the Americans and the state of armed terrorism, and they cannot at the same time support acts of murder and terrorism. &nbsp

The Degree of Coconvex Multi Polynomial Approximation

More information can be found in the full paper

Nano Geochemistry of Low Salinity Enhanced Oil Recovery

In this thesis a wide range of analytical techniques were used to characterise several petrophysical properties of Berea sandstone, including the mineral distribution at the pore surface and its pore structure, both playing a crucial role in determining its response to low salinity enhanced oil recovery (EOR) investigations. In addition, the role of different cations in affecting the wettability state of pure quartz and Berea sandstone was experimentally investigated in order to gain an insight on the behaviour of sandstone reservoirs during low salinity waterflooding EOR. Results from the multi-technique, multi-scale characterisation of Berea indicate that the mineralogy exposed to the pore spaces is highly heterogeneous across different length scales, going down to the often-neglected nanoscale were significant amounts of phases identified as grain coatings. In addition, analysis of the porosity and pore-connectivity also requires a multi-length approach for its full characterisation to be realised. Both aspects are crucial to understand the role of mineral surface chemistry in determining oil/water and oil/minerals interactions in both experiments and field conditions. Investigations on wettability alteration using environmental scanning electron microscopy (ESEM) and contact angle measurements on ideal quartz surfaces showed that reduced salinity leads to a more water-wet state. These measurements were complemented with atomic force microscopy adhesion measurements on quartz surfaces, the results giving further insight into the role of nano-scale roughness on quartz surfaces in wettability alteration by increasing the amount of oil retained on the surface. Finally, similar wettability alteration experiments were performed on Berea sections. The effect of brine was consistent, reproducible and reversible and again showed a low salinity effect, i.e. a change to more water-wet conditions with lower salinity. The results also demonstrate that quartz surfaces always contributes at least in part to the low salinity effect, decreasing oil wettability when salinity is low. In addition, we demonstrate that the ESEM can be an essential tool in studying the wettability alteration of rocks and minerals

Discourses on wars and conflicts :the discursive construction of Iraq in the US press

PhD ThesisThis study examines the discourses of US newspapers during the Iraq-Iran war (1980-1988) and the 2003 US-led invasion of Iraq to see how the themes: i.e., Saddam, Iraqi people, Shiites, Halabja/the use of chemical weapons are discursively represented in these two wars. The research also examines whether there is a shift in the US press stance in its reporting by comparing the treatment of the themes during the two wars in question. To operationalise an interdisciplinary framework for this investigation the study employs corpus linguistics tools: frequency, collocates and concordances, in combination with the Discourse Historical Approach (DHA) to CDA. The investigation reveals that during the Iraq-Iran war, the US press covered the conflicting official statements of all countries involved in the war, while there was an over-reliance on the opinions and statements of US officials during the US-led invasion, with Saddam’s voice being muted. In the same vein, although Saddam is portrayed negatively in the Iraq-Iran war, he is much more sharply vilified, Hilterlised and demonised in the US-led invasion, and constructed as a threat that needs to be faced and eliminated. With regard to the Iraqis/Shiites, there is also a shift in reporting in the two wars. In the 2003 US-led invasion they appear as worthy victims, a portrayal that fits in within the propaganda that the war had a humanitarian motive. However, the Iraqis/Shiites are never represented in this way during the Iraq-Iran war. In a similar way, whereas the US press coverage of Halabja and chemical weapons (in 1988) consists mainly of reports of the conflicting opinions and statements of Iraqi, Iranian and US officials during the Iran-Iraq war, this is not the case during the 2003 US-led invasion, when the history of the Halabja gassing and the use of chemical weapons by Iraq is brought back to the surface to serve the aims of demonising and criminalising Saddam in particular and Iraq in general: these events are used to support the claim that Iraq possessed WMDs and that there was a real threat that Saddam would use them. It is hoped that this thesis makes a multifaceted contribution to the field: first, in revealing the US press selective nature of human rights violations with regard to Iraqi social groups and showing how this was in line with US foreign policy; secondly, by contributing to our understanding of the quality of journalistic practices in the US during times of conflict and the way they may function to form the overall characteristics of US press discourses during iv international conflicts, especially conflicts in the Middle East. The study also highlights the mechanisms through which the US press discourses incorporate the official state voices in the processes of legitimising and persuading the public of the necessity for a war

Evaluation of Water Resources and Hydraulic Influences in the Restoration of the Western Part of the Mesopotamian Marshlands

The purpose of this study is to assess the water resources and water conveyance system of the western part of the Mesopotamian marshes (Al-Hammar marsh) as well as develop a water conveyance system to distribute water throughout the western Al-Hammar marsh. These processes are significant to identify the current restoration problems and help to create restoration strategies for the marsh. Also, proper management strategy to the Al-Hammar marsh is necessary to preserve the marsh ecosystem, irrigate lands, and provide domestic necessities in the villages. The overall project is divided into three main chapters which address the current ecological and hydrological issues in the western Al-Hammar marsh. Chapter 1 assesses the water used in the restoration of the western Al-Hammar after 2003. Chapter 1 also provides updated calculations concerning the water balance and the water needed for the planned restoration which promotes more efficient water management for the marsh. Chapter 2 looks at the current condition of the water conveyance system in the western Al-Hammar in order to identify its problems, such as water loss, hydraulic problems, and inefficiency. Creating a high efficiency distribution system for the water supply will increase the rate of inundation and promote better management of surface water resources as well as obtain benefits for agricultural irrigation. Chapter 3 discusses how the restoration could be improved with current available surface water resources using multiple feeding points instead several feeder canals, which improves the health of the marsh and rehabilitate the area. The results of the water balance have showed a deficit in water supplied to the marsh, even using the drainage water from the Main Outfall Drain (MOD), due to the high evapotranspiration (ET) and limited surface water resources, which do not have a constant flow to the marsh. The feeder canals are not efficient enough to supply water for both irrigation and restoration purposes in their current condition. Furthermore, they have many issues, including operation problems, insufficient maintenance, and water losses. Improving the feeder canals by creating a lined network of irrigation canals serve both the farmland and increase the restoration of the marsh