Channel assignment and routing in cooperative and competitive wireless mesh networks

This thesis was submitted for the degree of Docter of Philosophy and awarded by Brunel University.In this thesis, the channel assignment and routing problems have been investigated for both cooperative and competitive Wireless Mesh networks (WMNs). A dynamic and distributed channel assignment scheme has been proposed which generates the network topologies ensuring less interference and better connectivity. The proposed channel assignment scheme is capable of detecting the node failures and mobility in an efficient manner. The channel monitoring module precisely records the quality of bi-directional links in terms of link delays. In addition, a Quality of Service based Multi-Radio Ad-hoc On Demand Distance Vector (QMR-AODV) routing protocol has been devised. QMR-AODV is multi-radio compatible and provides delay guarantees on end-to-end paths. The inherited problem of AODV’s network wide flooding has been solved by selectively forwarding the routing queries on specified interfaces. The QoS based delay routing metric, combined with the selective route request forwarding, reduces the routing overhead from 24% up to 36% and produces 40.4% to 55.89% less network delays for traffic profiles of 10 to 60 flows, respectively. A distributed channel assignment scheme has been proposed for competitive WMNs, where the problem has been investigated by applying the concepts from non-cooperative bargaining Game Theory in two stages. In the first stage of the game, individual nodes of the non-cooperative setup is considered as the unit of analysis, where sufficient and necessary conditions for the existence of Nash Equilibrium (NE) and Negotiation-Proof Nash Equilibrium (N-PNE) have been derived. A distributed algorithm has been presented with perfect information available to the nodes of the network. In the presence of perfect information, each node has the knowledge of interference experience by the channels in its collision domain. The game converges to N-PNE in finite time and the average fairness achieved by all the nodes is greater than 0.79 (79%) as measured through Jain Fairness Index. Since N-PNE and NE are not always a system optimal solutions when considered from the end-nodes prospective, the model is further extended to incorporate non-cooperative end-users bargaining between two end user’s Mesh Access Points (MAPs), where an increase of 10% to 27% in end-to-end throughput is achieved. Furthermore, a non-cooperative game theoretical model is proposed for end-users flow routing in a multi-radio multi-channel WMNs. The end user nodes are selfish and compete for the channel resources across the WMNs backbone, aiming to maximize their own benefit without taking care for the overall system optimization. The end-to-end throughputs achieved by the flows of an end node and interference experienced across the WMNs backbone are considered as the performance parameters in the utility function. Theoretical foundation has been drawn based on the concepts from the Game Theory and necessary conditions for the existence of NE have been extensively derived. A distributed algorithm running on each end node with imperfect information has been implemented to assess the usefulness of the proposed mechanism. The analytical results have proven that a pure strategy Nash Equilibrium exists with the proposed necessary conditions in a game of imperfect information. Based on a distributed algorithm, the game converges to a stable state in finite time. The proposed game theoretical model provides a more reasonable solution with a standard deviation of 2.19Mbps as compared to 3.74Mbps of the random flow routing. Finally, the Price of Anarchy (PoA) of the system is close to one which shows the efficiency of the proposed scheme.The Higher Education Commission of Pakistan and the University of Engineering and Technology, Peshawar

Towards the Optimal Use of Machine Learning Algorithms in Text Mining: A Quick Review

This paper aims to provide a quick review to jump-start the research in the field of text mining where Machine Learning (ML) algorithms have been used and several accomplishments have been reported by the research community. There are different categories of text mining, and the implementation of ML algorithms and techniques have been supported in the literature to give promising results. However, in this area of study, most of the research activities in terms of time and efforts are consumed during the initial stages where implementations and experiments are carried out to evaluate various combinations. The accomplishments in this field can be further advanced by presenting early investigations concisely and analytically. Thus, the benefits of this paper are threefold: first, it will provide a platform for the new researchers to start quickly with a shorter literature review and knowing more precisely about the combinations of text mining and ML; secondly, clear analysis has been presented about the text mining categories where the performance of ML algorithms have been reported successful; and lastly, the problems have been identified for which the algorithms were used in various studies. This will enable the new researchers to directly target the problem instead of implementing the existing techniques. With the help of well-structured questions, the results are more analytical and present multidimensional views to this research issue. Main findings include that ML has been widely used in document classification and Support Vector Machine (SVM) is the most successful algorithm reported

Modal Analysis of a Single-Structure Multiaxis MEMS Gyroscope

This paper reports on designing a single-structure triaxes MEMS capacitive gyroscope which is capable of measuring the three angular velocities on a single drive. A Z-shaped beam for the support of folded coupling spring has been applied to suppress the unwanted mode and decrease the stress effect at the spring ends. The unique coupling spring has changed the driving motion, due to which slide film damping in the driving mode has been reduced. This reduction can lead to higher performance of the sensor with less requirements on vacuum level which decreases the cost of fabrication. Simulation analysis has been performed in COMSOL Multiphysics and Matlab Simulink to finalize the design for fabrication. After finite element analysis, the driving, x-sensing, z-sensing, and y-sensing are, respectively, found to be 13.30 KHz, 13.40 KHz, 13.47 KHz, and 13.51 KHz

Channel assignment and routing in cooperative and competitive wireless mesh networks

In this thesis, the channel assignment and routing problems have been investigated for both cooperative and competitive Wireless Mesh networks (WMNs). A dynamic and distributed channel assignment scheme has been proposed which generates the network topologies ensuring less interference and better connectivity. The proposed channel assignment scheme is capable of detecting the node failures and mobility in an efficient manner. The channel monitoring module precisely records the quality of bi-directional links in terms of link delays. In addition, a Quality of Service based Multi-Radio Ad-hoc On Demand Distance Vector (QMR-AODV) routing protocol has been devised. QMR-AODV is multi-radio compatible and provides delay guarantees on end-to-end paths. The inherited problem of AODV’s network wide flooding has been solved by selectively forwarding the routing queries on specified interfaces. The QoS based delay routing metric, combined with the selective route request forwarding, reduces the routing overhead from 24% up to 36% and produces 40.4% to 55.89% less network delays for traffic profiles of 10 to 60 flows, respectively. A distributed channel assignment scheme has been proposed for competitive WMNs, where the problem has been investigated by applying the concepts from non-cooperative bargaining Game Theory in two stages. In the first stage of the game, individual nodes of the non-cooperative setup is considered as the unit of analysis, where sufficient and necessary conditions for the existence of Nash Equilibrium (NE) and Negotiation-Proof Nash Equilibrium (N-PNE) have been derived. A distributed algorithm has been presented with perfect information available to the nodes of the network. In the presence of perfect information, each node has the knowledge of interference experience by the channels in its collision domain. The game converges to N-PNE in finite time and the average fairness achieved by all the nodes is greater than 0.79 (79%) as measured through Jain Fairness Index. Since N-PNE and NE are not always a system optimal solutions when considered from the end-nodes prospective, the model is further extended to incorporate non-cooperative end-users bargaining between two end user’s Mesh Access Points (MAPs), where an increase of 10% to 27% in end-to-end throughput is achieved. Furthermore, a non-cooperative game theoretical model is proposed for end-users flow routing in a multi-radio multi-channel WMNs. The end user nodes are selfish and compete for the channel resources across the WMNs backbone, aiming to maximize their own benefit without taking care for the overall system optimization. The end-to-end throughputs achieved by the flows of an end node and interference experienced across the WMNs backbone are considered as the performance parameters in the utility function. Theoretical foundation has been drawn based on the concepts from the Game Theory and necessary conditions for the existence of NE have been extensively derived. A distributed algorithm running on each end node with imperfect information has been implemented to assess the usefulness of the proposed mechanism. The analytical results have proven that a pure strategy Nash Equilibrium exists with the proposed necessary conditions in a game of imperfect information. Based on a distributed algorithm, the game converges to a stable state in finite time. The proposed game theoretical model provides a more reasonable solution with a standard deviation of 2.19Mbps as compared to 3.74Mbps of the random flow routing. Finally, the Price of Anarchy (PoA) of the system is close to one which shows the efficiency of the proposed scheme.EThOS - Electronic Theses Online ServiceHigher Education Commission of PakistanUniversity of Engineering and Technology, PeshawarGBUnited Kingdo

Metasurface-based wideband MIMO antenna for 5G millimeter-wave systems

This paper presents a metasurface based multiple-input multiple-output (MIMO) antenna with a wideband operation for millimeter-wave 5G communication systems. The antenna system consists of four elements placed with a 90 degree shift in order to achieve a compact MIMO system while a 2× 2 non-uniform metasurface (total four elements) is placed at the back of the MIMO configuration to improve the radiation characteristics of it. The overall size of the MIMO antenna is 24× 24 mm2 while the operational bandwidth of the proposed antenna system ranges from 23.5-29.4 GHz. The peak gain achieved by the proposed MIMO antenna is almost 7dB which is further improved up to 10.44 dB by employing a 2× 2 metasurface. The total efficiency is also observed more than 80% across the operating band. Apart from this, the MIMO performance metrics such as envelope correlation coefficient (ECC), diversity gain (DG), and channel capacity loss (CCL) are analyzed which demonstrate good characteristics. All the simulations of the proposed design are carried out in computer simulation technology (CST) software, and measured results reveal good agreement with the simulated one which make it a potential contender for the upcoming 5G communication systems.This work was supported in part by the Universidad Carlos III de Madrid and the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant Agreement No 801538, and in part by the the Ministerio de Ciencia, Innovación y Universidades, Gobierno de España (MCIU/AEI/FEDER,UE) under Grant RTI2018-095499-B-C31

A Taxonomy of Text Mining

With a rapid increase in the volume of textual data on the Internet, extracting useful information through innovative text mining techniques has become crucial. In this context, terminology jargon in the literature related to text-mining creates ambiguity and has made it very difficult for researchers to focus in a specific direction and bring innovation. For example, review mining and opinion mining may have different applications, however, from a technical perspective, they are very similar. In this paper, we propose a classification of the text mining terminologies from the perspectives of technical and text-mining processes. The classification is based on a comprehensive literature survey and analysis. This research study presents a clear classification of text mining terminologies based on technical and text mining processes to resolve the issue of terminology jargon. By utilizing the proposed classification, researchers will be able to easily choose a specific direction instead of diverging amongst similar research problems, thereby, driving innovation. Further, the proposed classification will help advance and improve the overall research progress in all text-mining related fields

Effect of Strenuous Exercise on Various Blood Parameters in Polo Horses at High Altitude (3,734 M)

Horses require heaps of energy in order to perform well. Proper care and management should therefore be provided to the racehorses so as to keep they perform at their optimum. The experiment used for normal horses. The blood samples were collected in the morning before subjecting the horses to polo match/ strenuous exercise and immediately after the physical activity. Various blood tests such as the complete blood count, lipid, protein tests were done. Significant elevations in the white blood cells (WBC), hemoglobin (Hb) and some serological parameters in the blood polo horses were recorded after exercise. This study confirmed the findings of exercise on different blood parameters which can be possibly used as an index of fitness in horses

Standred interferon therapy and its Response rates in Chronic HCV Patients in District Mardan, Khyber Pakhtunkhwa

To eradicate the Hepatitis C Virus from the bodies of the infected individuals Interferon and Ribavirin based therapy is used. HCV is highly prevalent in District Mardan Khyber Pakhtunkhwa that is why it is important to determine the response of standard interferon based therapy in Chronic HCV patients of this region. A total of 215 patients were selected for interferon based therapy. The patients were selected from three different Tehsil of District Mardan. After confirmation of active HCV infection by q-PCR, standard interferon with Ribavirin was given to patients for 6 months. After completion of therapy, end of treatment virologic response (ETR) was calculated. After completion of the 6 months long therapy, the results obtained were as. Out of total 215 patients, 168 (78.13%) were negative for HCV RNA and showing end of treatment response (ETR) while 47 (21.86%) were positive for HCV RNA and did not show ETR. In Tehsil Mardan, out of 102 patients who had completed therapy, 76 patients (74.51%) showed ETR and 26 (25.49%) did not show the ETR. In Tehsil Kattlang, we found that out of total 51 patients who had taken 6 months therapy, 41 (80.39%) were negative for HCV RNA and 10 (19.61%) were resistant to therapy while in Tehsil Tkhatbhai, out of 62, 50 (80.64%) were negative and 12 (19.35%) were positive. The above discussion shows that antiviral therapy against HCV infection in chronic HCV patients of District Mardan KPK province is 78.13%. The high response rate may be due to the prevalence of genotypes 2 and 3

Design of high gain base station antenna array for mm-wave cellular communication systems

Millimeter wave (mm-Wave) wireless communication systems require high gain antennas to overcome path loss effects and thereby enhance system coverage. This paper presents the design and analysis of an antenna array for high gain performance of future mm-wave 5G communication systems. The proposed antenna is based on planar microstrip technology and fabricated on 0.254 mm thick dielectric substrate (Rogers-5880) having a relative permittivity of 2.2 and loss tangent of 0.0009. The single radiating element used to construct the antenna array is a microstrip patch that has a configuration resembling a two-pronged fork. The single radiator has a realized gain of 7.6 dBi. To achieve the gain required by 5G base stations, a 64-element array antenna design is proposed which has a bore side gain of 21.2 dBi at 37.2 GHz. The 8 × 8, 8 × 16, and 8 × 32 antenna array designs described here were simulated and optimized using CST Microwave Studio, which is a 3D full-wave electromagnetic solver. The overall characteristics of the array in terms of reflection-coefficient and radiation patterns makes the proposed design suitable for mm-Wave 5G and other communication systems.Dr. Mohammad Alibakhshikenari acknowledges support from the CONEX-Plus programme funded by Universidad Carlos III de Madrid and the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 801538. In addition, this work was partially supported by Ministerio de Ciencia, Innovación y Universidades, Gobierno de España (Agencia Estatal de Investigación, Fondo Europeo de Desarrollo Regional -FEDER-, European Union) under the research grant PID2021-127409OB-C31 CONDOR. The authors also sincerely appreciate funding from Researchers Supporting Project number (RSP2023R58), King Saud University, Riyadh, Saudi Arabia

Identification of Proteins Differentially Expressed in the Striatum by Melatonin in a Middle Cerebral Artery Occlusion Rat Model—a Proteomic and in silico Approach

Ischemic stroke is characterized by permanent or transient obstruction of blood flow, which initiates a cascading pathological process, starting from acute ATP loss to subsequent membrane depolarization, glutamate excitotoxicity, and calcium overload. Melatonin is a potent antioxidant that exerts protective effects in different experimental stroke models. In this study, melatonin effects were demonstrated by a proteomic and in silico approach. The proteomic study identified differentially expressed proteins by 2D gel electrophoresis in the striatum 24 h after middle cerebral artery occlusion. Proteomic analysis revealed several proteins with aberrant expression and was validated by western blot and immunofluorescence analysis. Homology modeling was performed to build 3D structures for γ-enolase, thioredoxin (TRX), and heat shock 60 (HSP60) by the template crystal structures using a protein data bank as a sequence database. The structure refinement of each model was achieved by energy minimization via molecular dynamic simulation, and the generated models were further assessed for stability by Procheck and ProSA. The models were processed for docking analysis using AutoDock Vina, and post-docking analysis was determined by discovery studio. The proteomic study showed decreased expression of γ-enolase, TRX, and protein phosphatase 2A subunit B and increased expression of collapsin response mediator protein 2 and HSP60 in the striatum after ischemic injury. Treatment with melatonin modulated the expression profiles of these proteins. This study demonstrated the neuroprotective role of melatonin in the ischemic striatum using a proteomic and in silico approach. Collectively, melatonin may act in a multimechanistic way by modulating the expression of several proteins in the ischemic striatum