Cloud providers seek to maximize their market share. Traditionally, they deploy datacenters with sufficient capacity to accommodate their entire computing demand while maintaining geographical affinity to its customers. Achieving these goals by a single cloud provider is increasingly unrealistic from a cost of ownership perspective. Moreover, the carbon emissions from underutilized datacenters place an increasing demand on electricity and is a growing factor in the cost of cloud provider datacenters. Cloud-based systems may be classified into two categories: serving systems and analytical systems. We studied two primary workload types, on-demand video streaming as a serving system and MapReduce jobs as an analytical systems and suggested two unique energy mix usage for processing that workloads. The recognition that on-demand video streaming now constitutes the bulk portion of traffic to Internet consumers provides a path to mitigate rising energy demand. On-demand video is usually served through Content Delivery Networks (CDN), often scheduled in backend and edge datacenters. This publication describes a CDN deployment solution that utilizes green energy to supply on-demand streaming workload. A cross-cloud provider collaboration will allow cloud providers to both operate near their customers and reduce operational costs, primarily by lowering the datacenter deployments per provider ratio. Our approach optimizes cross-datacenters deployment. Specifically, we model an optimized CDN-edge instance allocation system that maximizes, under a set of realistic constraints, green energy utilization. The architecture of this cross-cloud coordinator service is based on Ubernetes, an open source container cluster manager that is a federation of Kubernetes clusters. It is shown how, under reasonable constraints, it can reduce the projected datacenter’s carbon emissions growth by 22% from the currently reported consumption. We also suggest operating datacenters using energy mix sources as a VoltDB-based fast data system to process offline workloads such as MapReduce jobs. We show how cross-cloud coordinator service can reduce the projected data- centers carbon emissions growth by 21% from the currently expected trajectory when processing offline MapReduce jobs.

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Cognitive Radio (CR) encompasses a number of technologies which enable adaptive self-programing of systems at different levels to provide more effective use of the increasingly congested radio spectrum. CRs have potential to use spectrum allocated to TV services, which is not used by the primary user (TV), without causing disruptive interference to licensed users by using appropriate propagation modelling in TV White Spaces (TVWS). In this paper we address two related aspects of channel occupancy prediction for cognitive radio. Firstly, we continue to investigate the best propagation model among three propagation models (Extended-Hata, Davidson-Hata and Egli) for use in the TV band, whilst also finding the optimum terrain data resolution to use (1000, 100 or 30 m). We compare modelled results with measurements taken in randomly-selected locations around Hull UK, using the two comparison criteria of implementation time and accuracy, when used for predicting TVWS system performance. Secondly, we describe how such models can be integrated into a database-driven tool for CR channel selection within the TVWS environment by creating a flexible simulation system for creating a TVWS database.

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This research work is novel technique to control and optimize SSSC (Subsynchronous Series Controller) functions with degree of precision in between Qatar and Kingdom of Saudi Arabia. The SSSC model developed and simulated in order to identify and determine its control and functioning parameters by introducing new tuning parameters based on that the SSSC can be adjusted stringently to witness desired results lead to address outstanding reactive power management issue. The proposed new parameters are contributing significantly to control SSSC functions in multiple directions in a power system network in between QATAR and Kingdom of Saudi Arabia at different time-based transmission contingencies on the GCC Electrical-power grid. Strategically, the SSSC capacity and capability can be utilized fully in between Qatar and Kingdom of Saudi Arabia by introducing and optimizing its control and tuning parameters more tangibly under both steady and dynamic states.

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IEEE 802.11 WLAN indoor networks face major inherent and environmental issues such as interference, noise, and obstacles. At the same time, they must provide a maximal service performance in highly changing radio environments and conformance to various applications’ requirements. For this purpose, they require a solid design approach that considers both inputs from the radio interface and the upper-layer services at every design step. The modelization of radio area coverage is a key component in this process and must build on feasible work hypotheses. It should be able also to interpret highly varying characteristics of dense indoor environments, technology advances, service design best practices, end-to-end integration with other network parts: Local Area Network (LAN), Wide Area Network (WAN) or Data Center Network (DCN). This work focuses on Radio Resource Management (RRM) as a key tool to achieve a solid design in WLAN indoor environments by planning frequency channel assignment, transmit directions and corresponding power levels. Its scope is limited to tackle co-channel interference but can be easily extended to address cross-channel ones. In this paper, we consider beamforming and costing techniques to augment conventional RRM’s Transmit Power Control (TPC) procedures that market-leading vendors has implemented and related research has worked on. We present a novel approach of radio coverage modelization and prove its additions to the cited related-work’s models. Our solution model runs three algorithms to evaluate transmission opportunities of Wireless Devices (WD) under the coverage area. It builds on realistic hypotheses and a thorough system operation’s understanding to evaluate such an opportunity to transmit, overcomes limitations from compared related-work’s models, and integrates a hierarchical costing system to match Service Level Agreement (SLA) expectations. The term “opportunity” in this context relates also to the new transmission’s possibilities that related-work misses often or overestimates.

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New multimedia applications such as mobile video, high-quality Internet video or digital television requires high-performance encoding of video signals to meet technical constraints such as runtime, bandwidth or latency. Video coding standard h.265 HEVC (High Efficiency Video Coding) was developed by JCT-VC to replace the MPEG-2, MPEG-4 and h.264 codecs and to respond to these new functional constraints. Currently, there are several implementations of this standard. Some implementations are based on software acceleration techniques; Others, on techniques of purely hardware acceleration and some others combine the two techniques. In software implementations, several techniques are used in order to decrease the video coding and decoding time. We quote data parallelism, tasks parallelism and combined solutions. In the other hand, In order to fulfill the computational demands of the new standard, HEVC includes several coding tools that allow dividing each picture into several partitions that can be processed in parallel, without degrading neither the quality nor the bitrate.
In this paper, we adapt one of these approaches, the Tile coding tool to propose a pipeline execution approach of the HEVC / h265 decoder application in its version HM Test model. This approach is based on a fine profiling by using code injection techniques supported by standard profiling tools such as Gprof and Valgrind. Profiling allowed us to divide functions into four groups according to three criteria: the first criterion is based on the minimization of communication between the different functions groups in order to have minimal intergroup communication and maximum intragroup communication. The second criterion is the load balancing between processors. The third criterion is the parallelism between functions. Experiments carried out in this paper are based on the Zedboard platform, which integrates a chip Zynq xilinx with a dual core ARM A9. We start with a purely sequential version to reach a version that use the pipeline techniques applied to the functional blocks that can run in parallel on the two processors of the experimental Platform. Results show that a gain of 30% is achieved compared to the sequential implementation.

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Metal housing has been used extensively on portable communication devices such as on mobile phones and tablets. The choice of metal housing ranges from metallic rim to metallic back cover.  This metal housing tends to improve the outlook appearance of the mobile devices, and add mechanical strength towards the mobile devices.  However, from the aspect of the communication antenna, the metal housing often posts great challenges towards the flexibility in antenna design and reduction in antenna performance.  This paper presents an approach to overcome the challenges by integrating the metal housing of the mobile phone as part of the antenna, along with the introduction of tunable antenna concept to provide different forms of Aperture Tuning to the Cellular Main Antenna, to satisfy its wide frequency band coverages for the 2^nd, 3^rd and 4^th Generation (2G, 3G and 4G) mobile network.  

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A new coupled structure identification of Multi-Input Multi-Output (MIMO) Hammerstein models with separate nonlinearities is proposed. It is based on the use of the Recursive Least Squares (RLS) algorithm. A comparative study between a decoupled and coupled structures identification of MIMO Hammerstein models is discussed. A quadruple-tank process is used to illustrate the effectiveness of the new structure.

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This paper deals with the design of a new reconfigurable beam antenna used to improve the efficiency of spatial telemetry links on Nano-Satellite. This agile beam antenna is not built on the well-known array concept AESA (Agile Electronically Scanned Array) but using a new one called ARMA (Agile Matrix Radiating Antenna); MARPEM in French. In this paper there is the design of the circularly polarized matrix antenna, the generation of two beam forming modes, the design of the distribution circuit and the polarization circuits.

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Real estate pressures in modern electronics have resulted in the need for electrically small antennas, which have subsequently garnered interest amongst researchers and industry alike. These antennas are characterized by their largest dimensions translating to a fraction of the operating wavelength; such a diminutive size comes at the expense of reduced gain and efficiency, and a worse overall match to a corresponding power source. In order to compensate for this deterioration in performance, antenna designers must turn towards increasingly complex and voluminous geometries, well beyond the capabilities of traditional manufacturing techniques. We present voluminous metal antennas, based on a novel inverted-F design, and fabricated using the emergent selective electron beam melting manufacturing technique, a type of powder bed fusion process. As predicted by small antenna theory, simulation results presented show in increase in the antenna’s efficiency as it is voluminously expanded into the third dimension. Measurement results illustrate that key trends observed from simulations are upheld; however, further understanding of the electromagnetic properties of raw materials, in particular how these change during the printing process, is needed. Nevertheless, this type of additive manufacturing technique is suitable for rapid prototyping of novel and complex antenna geometries, and is a promising avenue for further research and maturation.

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This paper proposes extended-range high-speed control for an IPMSM drive system. A simple real-time tuning flux-weakening control algorithm is proposed and implemented to control an IPMSM drive system in a wide variable speed range, from 3 r/min up to 2700 r/min. This flux-weakening control algorithm does not require any motor parameters and only needs simple mathematical computations. The proposed drive system adjusts the angle between the d-axis and q-axis current to reach flux-weakening control. In addition, a multiple sampling predictive controller is implemented to enhance the dynamic responses of the proposed drive system, which yields improved overall transient responses, superior load responses, and good tracking responses. A detailed analysis of the proposed drive system’s stability is discussed as well. A 32-bit digital signal processor, TMS-320F-28335, is used to execute the predictive controller and the flux-weakening control algorithm for the IPMSM drive system. Experimental results can validate the theoretical analysis.

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The current advances in proteomic and transcriptomic technologies produced huge amounts of high-throughput data that spans multiple biological processes and characteristics in different organisms. One of the important directions in today’s bioinformatics research is to discover patterns of genes that have interesting properties. These groups of genes can be referred to as functional modules. Detecting functional modules can be accomplished by the deep analysis of protein-protein interaction (PPI) networks, gene expression profiles, or both. In this work the focus will be on Human protein-protein interaction network and genes expression data that represents genes behavior in a group of diseases. Two of the most well-established clustering methods that target the interaction networks and the expression data will be used in this analysis. In addition, and to have more insights, genes molecular functionality will be studied. Finally, I will introduce the relation of the extracted modules on biological pathways. This study mainly illustrates the importance of including protein interaction activities as part of any study that aims at discovering meaningful knowledge about the biological scene where many actors play different roles.

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This paper presents the modelling and analysis of permanent magnet synchronous generator (PMSG) which are used in direct driven small scale wind turbines. The 3 kW PM generator which is driven directly without gear system is analyzed by Ansoft Maxwell 2D RMxprt. The performance analysis of generator includes the cogging torque in two teeth, induced coil voltages under load, winding current under load, airgap flux density distribution and so on. The modelling analysis is based on the 2D finite element techniques. In an electrical machine, an accurate determination of the geometry parameters is a vital role. The proper performance results of 3kW PMSG in small scale wind turbine can be seen in this paper.

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A switched capacitor low-pass filter employing folded-cascode CMOS OP Amps with a dynamic switching bias circuit capable of processing video signals, which enables low power consumption, and operation in wide bandwidths and low power supply voltages, is proposed. In this filter, charge transfer operations through two-phase clock pulses during the on-state period of the OP Amps and a non-charge transfer operation during their remaining off-state period are separated. Through simulations, it was shown that the low-pass filter with an OP Amp switching duty ratio of 50 % is able to operate at a 14.3 MHz high-speed dynamic switching rate, allowing processing video signals, and a dissipated power of 68 % of that observed in the static operation of the OP Amps and a full charge transfer operation without separation of a cycle period. The gain below -31 dB in the frequency response, which is suitable, was obtained at over 6 MHz within a stop-band. Especially high attenuation in 5 MHz was achieved under the optimized condition of load capacitances (4 pF) of OP Amps.

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In acronym Captology – Computers as Persuasive Technology, a persuasive component (lat. persuasibilibus – enticing) refers to the persuasive stimulation by intelligent technologies. Latter being transitive and interactive as intelligent systems, they have imposed, by their persuasivity, a ‘cult of information’, after which information has become a type of goods that as a utilitarian resource must be exploited quickly and efficiently. Such a widely accepted fact resulted as hype, presenting a perspective that the approach to a large amount of information and faster ‘digestion’ of their content will enable users to quickly get desired knowledge.
Recent investigations about persuasion processes have shown its dependence on intelligent technology factors (design, interactive computer products, web, desktop and others). Such technologies are also used to influence people’s attitudes, beliefs, learning, and behaviour. Development strategies for global computer production and sales head in that direction and confirm latter statement with the promoted 3-P model: persuasive, permissive and pervasive components. Cognitive level of human integrated development is increasingly overshadowed by the contribution of artificial intelligence through its products, i.e. ‘smart’ creations, and by the array of shortcomings and problems that the same interactive technology brings. This paper presents a parallel between captological component of intelligent and interactive technologies on one side and illustrates examples of captological influences proved by confirmed trials within cognitive science through computer simulations of human thinking on the other side. Many studies have shown that the success of persuasion depends on the factors which have been exposed by cognitive cybernetics. Next to it, people’s behavior system is transforming through the very development of society. Therefore, the influence of latter can be either positive or negative, while its extremes are already escalating in direction of a new trans-singularity and post humanism theories based on the principles of extropy.

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This paper proposes the modeling and control of a Solid-State Transformer using a three-stage conversion topology. First, a rectification stage is used, where a three-phase high-voltage AC signal is converted to a DC level; this stage is then followed by a DC-DC converter, and finally an inverter is used to convert the DC into a three-phase low-voltage AC signal. The adopted topology is modeled using a simplified model for each stage, useful to design their controllers. Based on these models, the controllers are tuned to obtain a good performance to sudden load changes. This performance is tested through simulations.

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In this paper, a hybrid system solar cell antenna was studied. Our contribution lies in the combination of both optical and radio-frequency signals in a solar cell antenna. Hence, we propose a new method to merge antenna and solar cell. The leaf- shaped patch solar cell antenna was dedicated at a time to the energy harvesting and the RF transmission. A performance analysis of the solar cell antenna was conducted using Advanced Design System (ADS) software. Simulation results showed a resonance at a frequency of 15.77 GHz with an effective return loss of -27.62dB and a gain of 5.77dBi.

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Combinatorial optimization is an area of great importance since many of the real-world problems have discrete parameters which are part of the objective function to be optimized. Development of combinatorial optimization algorithms is guided by the empirical study of the candidate ideas and their performance over a wide range of settings or scenarios to infer general conclusions. Number of scenarios can be overwhelming, especially when modeling uncertainty in some of the problem’s parameters. Since the process is also iterative and many ideas and hypotheses may be tested, execution time of each experiment has an important role in the efficiency and successfulness. Structure of such experiments allows for significant execution time improvement by distributing the computation. We focus on the cloud computing as a cost-efficient solution in these circumstances. In this paper we present a system for validating and comparing stochastic combinatorial optimization algorithms. The system also deals with selection of the optimal settings for computational nodes and number of nodes in terms of performance-cost tradeoff. We present applications of the system on a new class of project scheduling problem. We show that we can optimize the selection over cloud service providers as one of the settings and, according to the model, it resulted in a substantial cost-savings while meeting the deadline.

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Environmental sound recognition (ESR) has become a hot topic in recent years. ESR is mainly based on machine learning (ML) and ML algorithms require first a training database. This database must comprise the sounds to be recognized and other related sounds. An ESR system needs the database during training, testing and in the production stage. In this paper, we present the design and pilot establishment of a database which will assists all researchers who want to establish an ESR system. This database employs relational database model which is not used for this task before. We explain in this paper design and implementation details of the database, data collection and load process. Besides we explain the tools and developed graphical user interface for a desktop application and for the WEB.

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In modern powers systems, one of the most considerable topics is economic load dispatch (ELD). ELD is non-linear problem and it became non-convex and non-smooth problem with some constraints such as valve point loading effect. ELD is very crucial for energy generation and distribution in power systems. For solving ELD problem, a lot of methods were developed and used at different power systems. Vortex search algorithm (VSA) is proposed and applied for solving ELD problem in this paper. VSA method was developed in the form of stirring liquids. Transmission line losses, valve point loading effect, ramp rate limits and prohibited zones constraints were used to make the results of ELD problem the closest to the truth. The results which are obtained from VSA compared with PSO, CPSO, WIPSO, MFO, GA and MRPSO techniques. It can be clearly seen that VSA gave minimum cost values with optimum generator powers so it is very effective and useful method and it gave the best solutions for ELD.

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The automotive industry has focused to use polymer materials in order to increase energy efficiency. So, the industry pays attention to use 3D printing technologies using several polymers. Among several 3D printer technologies, fused deposition modeling (FDM) is one of the popular 3D printing technologies due to an inexpensive extrusion machine and multi-material printing. FDM could use thermoplastics such as ABS, PLA, ULTEM so on. However, it has a problem related to the post-processing because FDM has relatively poor layer resolution. In this study, the mechanical properties of ABS parts fabricated by FDM were measured. The ABS parts were divided into one with vapor smoothing process and the other without the vapor smoothing process which is one of the post-processing methods. Using dynamic mechanical analysis (DMA) and dilatometer, temperature-dependent storage modulus and CTE for ABS specimens were measured. Based on the measured thermo-mechanical properties of ABS parts, finite element analysis was performed for an automotive bumper made of ABS. Moreover, response surface methodology was applied to study relationships among design parameters of thickness of the bumper, ambient temperature, and application of the vapor smoothing process. In result, a design guideline for a ABS product could be provided without time-consuming experiments

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The paper shows a method of transforming an asynchronously feedbacked Mealy machine into a Moore machine. The transformation is done in dual-rail logic under the use of the RS-buffer. The transformed machine stabilizes itself and is safe to use. The transformation is visualized via KV-diagrams and calculated with formulas. We will present three use-cases for a better understanding. To underpin the stated transformation a simulation is also presented.

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When we drive a car, we often want to know the circumstances of roads between the current location and the destination. Ishihara et al. proposed a Vehicular ad-hoc NETworks (VANET) -based information sharing system, called the Real-Time Visual Car Navigation System, in which a driver can obtain Location-Dependent Information (LDI), such as photographs or videos of his/her Point of Interest (PoI), by telling the onboard device, e.g., a car navigation device, the PoI. The simplest way to provide LDI to vehicles is to flood the LDI to all vehicles, but unneeded LDI may be disseminated, and network resources may be wasted. To disseminate LDI to many vehicles that demand it with low communication traffic, we have proposed a data dissemination scheme based on Demand maps (Dmaps). In this scheme, each vehicle has a Dmap, a data set representing the geographical distribution of the strength of demands for LDI. To keep the Dmap up to date, each vehicle exchanges a subset of data constituting a Dmap (Dmap Information: DMI) with other vehicles. Vehicles preferentially send new LDI or forwarded LDI strongly demanded to the area where the LDI is frequently demanded based on Dmaps. If vehicles frequently send DMI, the accuracy of the Dmap becomes high, however, communication traffic becomes large. In this paper, we propose strategies for controlling the frequency of sending DMI and strategies for selecting DMI to be sent to improve the Dmap accuracy with low communication traffic. Simulation results show that one of the proposed strategies, the LDI Transfer Zone (LTZ) strategy, achieves highly accurate Dmaps with a small amount of communication traffic.

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This paper deals with the problem of Fault Tolerant Control (FTC) using PID-type Fuzzy Logic Controller (FLC) for an Electronic Throttle Valve (ETV) described by a switched discrete-time system with input disturbances and actuator faults. In order to detect the faults, Unknown Input Observers (UIOs) are designed and formulated in terms of Lyapunov theory and Linear Matrix Inequalities (LMIs). This approach is designed in order to minimize the error between the desired flat trajectory generated using the flatness property and the estimated state provided from differents UIOs and to maintain asymptotic stability under an arbitrary switching signal, even in the presence of actuator faults. The simulation results have shown the effectiveness of the proposed approach.

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Radio frequency Identification (RFID) is currently considered as one of the most used technologies for an automatic identification of objects or people. Based on a combination of tags and readers, RFID technology has widely been applied in various areas including supply chain, production and traffic control systems. However, despite of its numerous advantages, the technology brings out many challenges and concerns still not being attracting more and more researchers especially the security and privacy issues. In this paper, we review some of the recent research works using RFID solutions and dealing with security and privacy issues, we define our specific parameters and requirements allowing us to classify for each work which part of the RFID system is being secured, the solutions and the techniques used besides the conformity to RFID standards. Finally, we present briefly a solution that consists of combining RFID with smartcard based biometric to enhance security especially in access control scenarios. Hence the result of our study aims to give a clear vision of available solutions and techniques used to prevent and secure the RFID system from specific threats and attacks.

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This paper presents an analysis of a parallel connection of one synchronous generator and one self-excited induction generator that feeds a resistive load and an Induction Motor. The system voltage and frequency are controlled by a voltage control loop and a speed control loop connected to synchronous generator. The induction generator speed is controlled by its primary machine that is fed by an autotransformer and a diodes bridge. Through by voltages applied by an adjustable tap autotransformer connected to induction generator’s primary machine, it is possible widen the range of its shaft speed if compared with the shaft speed caused by only field flux variation method. Then, by the autotransformer method is possible to widen the speed and power limits from the induction generator what increases the induction generator contributions and relieves the power supply from synchronous generator. Analysis of generators power supply and its interactions in various operational scenarios are shown. The results enable comparisons of the two methods of induction generator speed control, either by auto-transformer method or by field flux variation method. The first results in larger range of speed and power from the induction generator. Therefore, it has more representative features of actual field conditions.

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In remote measurements on large-sized objects main focus is on measuring deformations of bridge surfaces and determination of the dynamic amplification factor in particular. The proposed method estimates deflections of entire lower surface of a bridge due to placement of secondary radiators on this surface. Antenna array directivity pattern (ADP) is distorted during deflection of the bridge surface. ADP distortions contain the information about deflections of the individual points of the surface. Minimization of the distance in a functional space with a quadratic metric (the functional) between a distorted measured ADP and theoretical one allows us to determine these deflections. The main problem is measurement of the secondary radiators system ADP in far zone which often cannot be achieved for real bridges in practical situations. Therefore, a new method for determining surface deflections based only on field amplitude measurements in near-field zone of a secondary radiators system is considered in the article. This amplitude of field strength depends on the bridge surface deflection. The modulus of difference between the normalized amplitude distribution of the measured field at the outputs of the receiving array elements, which is created by the radiators system of an unloaded bridge, and the similar amplitude field distribution of a loaded bridge is minimized and deflection of the bridge at the points of the radiating elements placement is calculated.

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Two technology trends – a move toward software defined capabilities and toward networked devices – support both unprecedented innovations and requirements for security. A fundamental aspect of security is user authentication, which allows devices and software applications to establish their user’s identity and identity is in turn used to establish which of its capabilities the user is authorized to access. While multiple authentication steps, known as multifactor authentication, are being used more widely throughout the military, government, businesses, and consumer sectors, the selection and implementation of which authentication factors to require is typically defined by security policy. Security policy is in turn typically established by a security organization that may have no formal metrics or means to guide its selection of authentication factors. This paper will present a taxonomy for describing authentication factors including important attributes that characterize authentication robustness to aid in the selection of factors that are consistent with the user’s mission. One particular authentication factor that I have developed will be discussed in the context of this taxonomy to motivate the need to broaden current definitions and security policies. The ultimate goal of this paper is to inspire the development of standards for authentication technologies to both support mission aware authentication innovation and to inform decision making about security policies concerning user authentication and authorization. Further, this paper aims to demonstrate that such an approach will fundamentally enhance both security and usability of increasingly networked, software-defined devices, equipment and software applications.

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denotes circulant graph of order for a set where Circulant graph is said to have the Cayley Isomorphism (CI) property if whenever is isomorphic to , there is some for which . In this paper, isomorphic properties of circulant graphs that includes Self-complementary circulant graphs; Type-2 isomorphism, a new type of isomorphism other than already known Adam’s isomorphism of circulant graphs and Cartesian product and factorization of circulant graphs similar to the theory of product and factorization of natural numbers are studied. New abelian groups are obtained from these isomorphic circulant graphs. Type-2 isomorphic circulant graphs have the property that they are isomorphic graphs without Cayley Isomorphism (CI) property and thereby new families.

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The efficiency of a plasma-aided finishing process, namely capillary impregnation, can be predicted only by setting two basic parameters of the real wood porous surface and the actual impregnating solution – surface free energy and surface tension. In general, the following processing efficiency parameter was found and the rule is true: “The plasma aided or enhanced finishing of a porous media will be more successful and this media will be more susceptible to it as the difference between its surface free energy and the surface tension or the so-called penetration-spreading parameter is positive: PSP = (?S – ?L) > 0. If not, wetting, wicking and finishing problems will occur.

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The aim of this paper is to develop a hybrid device for voltage stability enhancement using two kinds of FACTS (Flexible AC Transmission System) namely SVC (Static Var Compensator) and TCSC (Thyristor Controlled Series Capacitor). The idea behind the proposed method is to maintain safe and satisfactory power system operation in a lesser costing manner by taking advantage of the performances of SVC and TCSC at the same time. We propose to evaluate the efficacy of the combined device to UPFC, as it is a hybrid FACTS and it is the most versatile compensator. For purpose of identifying the placement of the devices, we opt for a heuristic based approach. The methodology is tested with the IEEE 14-Bus system using the software EUROSTAG, and the simulation results reveal the efficiency of the proposed method for enhancing voltage stability.

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This paper proposed the identification of the proper placement of UPFC (Unified Power Flow Controller) using a series of methodological numeric simulations to improve voltage stability. For this purpose, the critical zone of the system is determined, then, comparative analyses depending on different emplacements of UPFC are performed. The dynamic model of UPFC and the proposed method are tested on the IEEE 14-bus system. The finding shows that the proper location of UPFC helps in improving voltage profiles and increasing the maximum loading capacity.

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This paper is an extension of work originally presented in 2016 IEEE Asia-Pacific Conference on Applied Electromagnetics (APACE). A 2×1 microstrip patch array antenna integrated with photonic bandgap (PBG) and stubs is designed and analyzed. The performance of the PBG and stubs structure are explained and analyzed in terms of the elimination of the resonance at the harmonic frequencies of the antenna. The proposed antenna is designed on FR-4 substrate with thickness of 1.6 mm and operated at 2.45 GHz frequency suitable for rectenna design application. From the simulated result, the first harmonic frequency (5.4 GHz), the second harmonic frequency (6.6 GHz) and the third harmonic frequency (7.8 GHz) are successfully suppressed. For instance, the radiation to the forward of the stubs-PBG antenna is suppressed at more than 15 dB at the second and third harmonic frequencies.

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This article is devoted to the problem of blocking the propagation of sound in a gas stream. This can be useful in the problems of pipeline acoustics and the design of automotive silencers, when it is necessary to ensure the opacity of the boundary (cross section of the pipe) for sound simultaneously with the free (ideally) flow through this boundary. The tool for solving this problem is the rapid periodic overlapping of waveguide (gas-conducting) channels in a system of parallel waveguides. The design of the proposed device assumes the following technological requirements: high mechanical rigidity of the elements, high accuracy of their manufacture and high rotor speed. Fulfillment of these conditions allows creating an effective device for blocking sound in the gas flow. Such a device may have small wave dimensions (with respect to the wavelength of sound) and a small expenditure of mechanical power to push gas through it very wide frequency range of silencing.

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With the abundance of Internet and electronic devices bullying has moved its place from schools and backyards into cyberspace; to be now known as Cyberbullying. Cyberbullying is affecting a lot of children around the world, especially Arab countries. Thus concerns from cyberbullying are rising. A lot of research is ongoing with the purpose of diminishing cyberbullying. The current research efforts are focused around detection and mitigation of cyberbullying. Previously, researches dealt with the psychological effects of cyberbullying on the victim and the predator. A lot of research work proposed solutions for detecting cyberbullying in English language and a few more languages, but none till now covered cyberbullying in Arabic language. Several techniques contribute in cyberbullying detection, mainly Machine Learning (ML) and Natural Language Processing (NLP). This journal extends on a previous paper to elaborate on a solution for detecting and stopping cyberbullying. It first presents a thorough survey for the previous work done in cyberbullying detection. Then a solution that focuses on detecting cyberbullying in Arabic content is displayed and assessed.

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Water quality assessment and prediction is a more and more important issue. Traditional ways either take lots of time or they can only do assessments. In this research, by applying machine learning algorithm to a long period time of water attributes’ data; we can generate a decision tree so that it can predict the future day’s water quality in an easy and efficient way. The idea is to combine the traditional ways and the computer algorithms together. Using machine learning algorithms, the assessment of water quality will be far more efficient, and by generating the decision tree, the prediction will be quite accurate. The drawback of the machine learning modeling is that the execution takes quite long time, especially when we employ a better accuracy but more time-consuming algorithm in clustering. Therefore, we applied the high performance computing (HPC) System to deal with this problem. Up to now, the pilot experiments have achieved very promising preliminary results. The visualized water quality assessment and prediction obtained from this project would be published in an interactive website so that the public and the environmental managers could use the information for their decision making.

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The goal of this study was to use underwater robots instead of a diver’s observations to monitor and record the condition of an obstructed seabed in a shallow area. It is difficult to investigate marine resources that exist in deep water shaded by rock due to large and/or small rocks on the seabed. To solve these problems, we newly constructed a flexible lengthening-shortening arm with a small camera unit for an underwater robot to assist in the management of fishery resources. In this paper, we describe the concept and configuration of the newly developed arm mechanism using a sliding screw mechanism to overcome obstacles by changing arm posture in a two-dimensional plane, and we demonstrate the experimental results of a path-tracing controller for the rear links. The results were that the maximum deviations between the target path and the tracing path were less than 4.0% of the total width of the arm mechanism. These results suggest that the newly developed path-tracing algorithm is effective for our flexible lengthening-shortening arm mechanism.

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