Volume 3, Issue 3

This paper presents a numerical and experimental study of Radar Cross Section (RCS) of radar targets using Gaussian Beam Summation (GBS) method. The purpose GBS method has several advantages over ray method, mainly on the caustic problem. To evaluate the performance of the chosen method, we started the analysis of the RCS using Gaussian Beam Summation (GBS) and Gaussian Beam Launching (GBL), the asymptotic models Physical Optic (PO), Geometrical Theory of Diffraction (GTD) and the rigorous Method of Moment (MoM). Then, we showed the experimental validation of the numerical results using experimental measurements which have been executed in the anechoic chamber of Lab-STICC at ENSTA Bretagne. The numerical and experimental results of the RCS are studied and given as a function of various parameters: polarization type, target size, Gaussian beams number and Gaussian beams width.

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This work presents a comparison between controller tuning methods for a multivariable steam generator. Controller tuning has a remarkable impact on closed loop performance. Methods selected were Single-Loop Tuning (SLT), Biggest Log Modulus Tuning (BLT), Sequential Return- Difference (SRD) and Structured H(inf) Synthesis (S-H(inf)). Method assessment takes into account set-point tracking, disturbance rejection, tuning effort and stability.

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Memory based ternary physical unclonable functions contain cells with fuzzy states that are exploited to create multiple sources of physical randomness, and design true random numbers generators. A XOR compiler enhances the randomness of the binary data streams generated with such components, while a modulo-3 addition enhances the randomness of the native ternary data streams, also generated with the same method. Deviations from perfect randomness of these random numbers, in terms of probability to be non-random, was reported as low as 10-10 in the experimental section of this paper, which is considered as extremely random based on NIST criteria.

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The pitch angle controller maintains the aerodynamic captured power at rated level when the wind speed is above the rated speed. Besides, it can also improve the transient stability occurring in the wind energy system (WES). This paper, therefore, proposes an effective pitch angle control strategy that can deliver the conditioned output power in windy condition and increase the transient stability capability in grid faults. A fuzzy logic method has employed to design the proposed control strategy, Moreover, in this paper some major factors that affect the transient stability have been investigated by deriving steady-state equivalent model of the wind energy system. The simulated results show that the proposed fuzzy logic based pitch angle controller is effective at conditioning the output power and complying with fault ride through requirements for WES in the power system.

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Analysis of magnetic resonant wireless power transfer systems aims to achieve maximum efficiency of the power transfer. From the analysis we wish to derive the maximum power and the frequency at which this occurs. This paper presents a method to estimate these two required values and to achieve this requires the solution of the input impedance equation numerically. The frequency of the maximum efficiency is found when the imaginary of the input impedance is close to zero, and it could be different to the natural resonant frequency. We estimate the efficiency value which depends on the real value part of the input impedance. The proposed method has been applied to one of the four types of possible connections; a series-parallel (SP) connection although similar approaches could be applied to the others. In some cases the maximum efficiency shifts away from the resonant frequency. Therefore, this paper shows how to use the same equations to achieve maximum efficiency at resonance and suggests a design method to achieve this practically.

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During sudden anti-terrorist drives conducted by the law enforcement agencies, a localized cyber security system happens to be a special tactic to avert the unprecedented massacre and gruesome fatalities against the residents of that area by disconnecting the affected territory from the rest of the world; so that the militants and their outside accomplices cannot communicate with each other and also the terrorists cannot go through the ongoing apprehensive operation via wireless communications. This paper presents a novel framework of an unmanned aerial vehicular networking signal jammer which is oriented to block incoming and outgoing signals of all frequencies transmitted from a specifically marginalized territory scanned and explored by the aerial vehicle. During such a cyber-vigilance operation, the aerial vehicle is equipped with a transmitter and an auto-tuning band-pass filter module with automatic regulation of center frequencies according to the surrounding networking signals, which are considered to be the suppressing noise parameters. In order to restrict the signal blocking operation within the militant hub, the aerial vehicle with the network terminator is controlled to navigate within a particular boundary of a residential area and its navigation is continuously mapped and stored for effective evacuation process directed to save the innocent stranded people. A very low frequency (VLF) metal detector has been designed to trace the explosives and buried landmines inside the exploration arena. An algorithm for 3-D mapping of the metal traces detected by the aerial navigator has been presented in this paper. Signal blocking, metal tracing and stable confined movements have been tested where the testbed is provided with signals of different frequencies along with variation in dimensions of the testing region to evaluate the reliability of the proposed framework.

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Though AES is the highest secure symmetric cipher at present, many attacks are now effective against AES too which is seen from the review of recent attacks of AES. This paper describes an extended AES algorithm with key sizes of 256, 384 and 512 bits with round numbers of 10, 12 and 14 respectively. Data block length is 128 bits, same as AES. But unlike AES each round of encryption and decryption of this proposed algorithm consists of five stages except the last one which consists of four stages. Unlike AES, this algorithm uses two different key expansion algorithms with two different round constants that ensure higher security than AES. Basically, this algorithm takes one cipher key and divides the selected key of two separate sub-keys: FirstKey and SecondKey. Then expand them through two different key expansion schedules. Performance analysis shows that the proposed extended AES algorithm takes almost same amount of time to encrypt and decrypt the same amount of data as AES but with higher security than AES.

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Though AES is the highest secure symmetric cipher at present, many attacks are now effective against AES too which is seen from the review of recent attacks of AES. This paper describes an extended AES algorithm with key sizes of 256, 384 and 512 bits with round numbers of 10, 12 and 14 respectively. Data block length is 128 bits, same as AES. But unlike AES each round of encryption and decryption of this proposed algorithm consists of five stages except the last one which consists of four stages. Unlike AES, this algorithm uses two different key expansion algorithms with two different round constants that ensure higher security than AES. Basically, this algorithm takes one cipher key and divides the selected key of two separate sub-keys: FirstKey and SecondKey. Then expand them through two different key expansion schedules. Performance analysis shows that the proposed extended AES algorithm takes almost same amount of time to encrypt and decrypt the same amount of data as AES but with higher security than AES.

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During microwave heating of materials, the efficiency of microwave heating depends on the materials’ dielectric property, shapes and sizes of the material, materials’ position inside the applicator, operating frequency, level of input power, specific heat capacity, number and position of waveguide over the applicator, size and geometry of applicator etc. This paper examines the effects of dielectric properties of the clay sample placed in the multimode applicator on the performance of microwave heating. The simulated and experimentally obtained results show that the variation in clay samples dielectric value creates variation in system efficiency inside the microwave applicator. Also placing another dielectric slab over the material to be heated affects the electric field distribution and system efficiency. Placing KESTAMID dielectric slab over the material improved the heating efficiency by 22%. COMSOL Multiphysics software was used to simulate and estimate the electric field distribution over the surface of the clay sample and inside the multimode applicator for different dielectric property clay samples. The simulated and experimentally obtained results are almost matched.

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The rapid evolution of Collaborative e-Learning Systems migrates to the use of new technologies such the artificial intelligence (AI). In this context, the role of AI in increasing the quality of learning and making it more productive, persistent and efficient. In addition, it can accomplish repetitive and complex tasks in record time and unmatched accuracy. These advantages offer the ability to interact with learners in an almost human way. This interaction could be made on the base of adaptive hypermedia techniques, Multi-agent Systems technology and a cognitive learner model.
In this paper, we present and analyze some existing intelligent collaborative e-Learning systems on the basis of their various features such as collaboration features, intelligent actors’ interaction, adaptability measurement, cognitive student modeling, and security measurement. Our analysis aims to provide important information to researchers, educators and software developers of educational environments concerning strengths and weaknesses of those e-Learning systems. According to this study, we found that some collaborative e-Learning environments, even the use of the mentioned technologies, still poor in terms of the structure of human cognitive architecture aspects and the capacity to assess the help provided to learners. For these reasons, we present, in the end, some prospects in order to determine how we can improve these systems to stop the reasons of abandoning courses.

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The development of agent-based systems is negatively impacted by the lack of process standardization across the major development phases, such as the requirements analysis phase. This issue creates a key barrier for agent technology stockholders regarding comprehending and analyzing complexity associated with these systems specifications. Instead, such fundamental low-level infrastructure is loosely attended to in an ad-hoc fashion, and important aspects of requirements analysis are often neglected altogether. The IEEE Std 830 model is a recommended practice aimed at describing how to write better quality requirement specifications of conventional software. Knowing that agent-based computing is a natural and logical evolution of the conventional approaches to software development, we believe that the requirements phase in agent-based systems can benefit from applying the IEEE Std 830 model which results in high-quality and more accepted artifacts. This article provides a criteriabased evaluation that is derived from the software engineering body of knowledge guide to assessing the adoption degree of agent-oriented methodologies to software requirements standards. Then, it proposes a model-driven approach to restructuring and extending the IEEE Std 830- 2009 standard model to specify requirements of agent-based systems. To evaluate the applicability and usefulness of the updated model, we design a research study that allows practicing the model with simple real-world problem scenarios and conducting a summative survey to solicit feedback on the model usages.

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Multitenancy isolation is a way of ensuring that the performance, stored data volume and access privileges required by one tenant and/or component does not affect other tenants and/or components. One of the conditions that can influence the varying degrees of isolation is when locking is enabled for a process or component that is being shared. Although the concept of locking has been extensively studied in database management, there is little or no research on how locking affects multitenancy isolation and its implications for optimizing the deployment of components of a cloud-hosted service in response to workload changes. This paper applies COMITRE (Component-based approach to Multitenancy Isolation through Request Re-routing) to evaluate the impact of enabling locking for a shared process or component of a cloud-hosted application. Results show that locking has a significant effect on the performance and resource consumption of tenants especially for operations that interact directly with the local file system of the platform used on the cloud infrastructure. We also present recommendations for achieving the required degree of multitenancy isolation when locking is enabled for three software processes: continuous integration, version control, and bug tracking.

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To evaluate the effects of Ondansetron on the negative and depressive symptoms of patients with schizophrenia. A double-blind randomized control trial was conducted in 2016-17 in Lahore. 30 participants were included both in placebo and medicine group. The patients were assessed by using the Positive and Negative Syndrome Scale (PANSS) and Hamilton’s Rating Scale for Depression (HRSD) at baseline and at 12 weeks. The t-test and Chi square test were used to evaluate the data by using SPSS (version 21). The statistical significance was set at P<0.05. Ondansetron with risperidone has past impact on the negative symptoms as compared to placebo with risperidone (P=0.002). There was a significant difference between two groups after giving medicine and placebo as evaluated through WAIS-R scale. Ondansetron had significantly improved the visual memory that was based upon subsets of WAIS. Ondansetron has no role in the depressive symptoms (Effect size=0.15). Ondansetron can be used for the treatment of negative symptoms that are suffering from schizophrenia. It can be used as adjunctive therapy especially in cognitive impairment and negative symptoms.

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The objective was to review and add literature whether green tea is helpful for weight reduction. Reviewing the randomized, double-blind, placebo-controlled trials to compare green tea extracts for weight loss from various online sources including Ovid MEDLINE, PubMed, and Cochrane databases studies published in 2006, 2007 and 2008 in English language were considered. In each of the three studies, baseline measurements were taken and analyzed of the research participants. Measurements of total body weight, BMI with reference to age, hip and waist circumference were measured at the interval of 4 weeks i.e. 0 week (0 month), 4th week (1 month), 8th week (2 month), 12th week (3 month) were taken. All the research work analyzed and reviewed showed that a part of some minor changes no major changes were observed to prove the significance of green tea as a single agent for reducing weight. An increase in body energy expenditure was observed which leads to increase in appetite by the subjects but no adverse effects were noted. After detail review and analysis, the results showed that green tea have no significant effect on the weight reduction as a single agent.

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The objective was to review and add literature whether green tea is helpful for weight reduction. Reviewing the randomized, double-blind, placebo-controlled trials to compare green tea extracts for weight loss from various online sources including Ovid MEDLINE, PubMed, and Cochrane databases studies published in 2006, 2007 and 2008 in English language were considered. In each of the three studies, baseline measurements were taken and analyzed of the research participants. Measurements of total body weight, BMI with reference to age, hip and waist circumference were measured at the interval of 4 weeks i.e. 0 week (0 month), 4th week (1 month), 8th week (2 month), 12th week (3 month) were taken. All the research work analyzed and reviewed showed that a part of some minor changes no major changes were observed to prove the significance of green tea as a single agent for reducing weight. An increase in body energy expenditure was observed which leads to increase in appetite by the subjects but no adverse effects were noted. After detail review and analysis, the results showed that green tea have no significant effect on the weight reduction as a single agent.

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Face recognition is one of the most well-known biometric methods. It is a technique used for identifying individual from his face. The recognition process takes the face and compares it with the one stored in the database for recognizing it. Many methods were proposed to achieve that. In this paper, a new technique is proposed by using meta-heuristic algorithm. The algorithm is used to search for the best point in the image to be selected as a pivot, generate a vector of extracted features that are not necessary for the recognition and may reduce accuracy of it and evaluate the weight value for each area in the face image areas. A dataset with 371 images was used for evaluation. The results were conducted and compared with the original face recognition technique. That results show that proposed idea could enhance recognition by increasing accuracy up to 20% over original face recognition technique.

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The principal goal of this paper is the development of the experimental software solution for the extraction of dimensional unit from the uncalibrated image. Existing techniques are analyzed and also partially utilized in presented approach as an aid in the extraction process. The design of two different approaches was proposed, these were later implemented and tested. Proposed methods cover utilization of homography matrix, vanishing points and vanishing line. Developed system allows to determine the dimension of any object in image based on the value of reference dimension. Proposed software solution was tested in laboratory and real-world environment.

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Multiprocessing can be considered the most characteristic common property of complex digital systems. Due to the more and more complex tasks to be solved for fulfilling often conflicting requirements (cost, speed, energy and communication efficiency, pipelining, parallelism, the number of component processors, etc.), different types of component processors may be required by forming a so called Heterogeneous Multiprocessing Architecture (HMPA). The component processors of such systems may be not only general purpose CPUs or cores, but also DSPs, GPUs, FPGAs and other custom hardware components as well. Nevertheless, the system-level design process should be capable to handle the different types of component processors the same generic way. The hierarchy of the component processors and the data transfer organization between them are strongly determined by the task to be solved and by the priority order of the requirements to be fulfilled. For each component processor, a subtask must be defined based on the requirements and their desired priority orders. The definition of the subtasks, i.e. the decomposition of the task influences strongly the cost and performance of the whole system. Therefore, systematically comparing and evaluating the effects of different decompositions into subtasks may help the designer to approach optimal decisions in the system-level synthesis phase. For this purpose, the paper presents a novel method called DECHLS based on combining the decomposition and the modified high level synthesis algorithms. The application of the method is illustrated by redesigning and evaluating in some versions of two existing high performance practical embedded multiprocessing systems.

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This paper is an extension of work originally presented in conference name” Study Performance of Speed Tracking Control with Frequency and Amplitude Dependence”. Though many PMSMs (Permanent Magnet Synchronous Motor) control approach have already been published, little endeavors have been invested in the study of speed tacking control with frequency or amplitude dependence. The use of NDI (Nonlinear Dynamic Inversion) tracking control in versus amplitude and frequency dependence is the major focus of this paper. The proposed tracking control demonstrates that NDI control presents the ability to track the desired output with high precision. PMSM outputs are characterized at different amplitude and frequency. The speed and the direct current versus amplitude and frequency are successfully extracted. A mathematical (d-q) of the permanent magnet synchronous motor model is also presented. A comparative study between desired data and simulation results is conducted. Important to note, the proposed model and the simulation results reflect a successful agreement as far as a amplitude and frequency dependence is concerned. A new validity approach, namely “Validity Abacus” is proposed and discussed.

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Residential schools can be a great place for students to learn and develop a different set of skills if the right environment is given to the child. Constant communication with parents can help the child to stay motivated and feel comfortable away from home, hence schools tend to provide various solutions to allow the student to communicate with their parents. The most common ways are using a coin booth or a common telephone. This process is very hectic as hundreds of student’s use this facility and these hundreds of calls have to be monitored individually so that no student would be getting into bad influence. In order to counter this problem, the entire process is automated in this paper. The proposed work also countered every small problem, such as unauthorized access, making calls to unauthorized numbers or exceeding the duration of call time allotted. In this paper, the digital lines are used to allow multiple calls and control these with the help of a Primary Rate Interface (PRI) card and an Electronic Private Automatic Branch Exchange (EPABX) system.

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Multicore processor combines two or more independent cores onto one integrated circuit. Although it offers a good performance in terms of the execution time, there are still many metrics such as number of cores, power, memory and more that effect on multicore performance and reduce it. This paper gives an overview about the evolution of the multicore architecture with a comparison between single, Dual and Quad. Then we summarized some of the recent related works implemented using multicore architecture and show the factors that have an effect on the performance of multicore parallel architecture based on their results. Finally, we covered some of the distributed parallel system concepts and present a comparison between them and the multiprocessor system characteristics.

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A selective harmonic elimination system using fuzzy logic for the elimination of high magnitude harmonics with frequencies close to fundamental in the output voltage of single phase inverters is presented. The system does not require look up tables for storage of the data as in traditional harmonic elimination methods. The input of the fuzzy system is the modulation index values. The output of the fuzzy system provides the switching angles which are further used to construct the switching signal for the switches in the inverter. With this fuzzy logic based selective harmonic elimination system, predetermined dominant low rank harmonics are successfully eliminated. Simulations are made with Matlab/Simulink and the results are presented which show the effectiveness of the presented harmonic elimination system.

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