Volume 4, Issue 1

Large power transformers generally include a customer request for a technically appropriate regulation unit. The selection process of the regulation unit consists of defining the required input data, performing mathematical calculations necessary to find the technical limit values that the regulation unit has to satisfy, and finally optimizing and selecting the appropriate regulation unit. The number of possible permutations consists of thousands of different combinations, depending on the type of regulation and other technical limitations. The automation system presented in this paper significantly reduces the time required to obtain the optimal regulation unit solution in both offer and order stages of the project, providing significant overall productivity increase. This paper presents an example of managing a part of a complex system such as power transformer design using a software solution. The process of finding the optimal regulation unit „manually” can take up to several hours. Implementing the developed algorithm and introducing Tap Changer Selection application, the required time is reduced to several minutes. This represents significant time savings and reduced possibility of errors, thus improving the power transformer design process.

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The frequency dependent grid impedance at the terminals of an electrical supply grid is an essential parameter for power quality and grid feedback analysis. In this contribution the identification of the grid impedance is achieved using spectral excitation currents at the corresponding grid connection point, which generate measureable changes in the grid voltage spectra. Different measurement systems based on this method have been successfully realized for the low- and medium-voltage level. A measurement system for the high-voltage level is currently being realized. The application of the measurement systems are facing quite different external framework conditions leading to specific system designs for each measurement device. The spectral grid impedance identification on these voltage levels is done through fast switching of an ohmic load with power electronic. The requirements and setup of the grid impedance measurement systems are outlined and measurement results on the low- and medium-voltage level are presented and discussed. The systems can be used to evaluate grid connection points and to verify other active or passive grid impedance identification methods on different voltage levels.

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As the technology grows scientists and engineers are trying to combine their work to compensate some body parts that is lost. Prosthetic devices grabbed the attention of most of the doctors and engineers working on solution for lost body parts. Generally prosthetic devices are either external wearable devices or internal ones. Such devices may depend on a built on microcontroller or the brain signals from the patient himself. Although it is used for lost body parts it can also be used for rehabilitation, power assistance, diagnostics, monitoring, ergonomics, etc. The currently used devices usually have the disadvantages of big size and high cost. The suggested device in this paper is targeting the design of portable rehabilitation device with light weight and low cost for paralyzed hand people. The suggested device allows the user to train the patient’s hand or perform some needed exercises for his impaired hand. This helps the user to restore the normal hand movement and functionality. The device includes two modes of operation to be chosen by the user through the platform built on a microprocessor which can help controlling the exoskeleton to perform the needed exercises or tasks. Collaboration with several healthcare organizations will be considered to verify or test the effectiveness of this exoskeleton.

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We present a privacy-preserving approach for discovering nearby places of interest to Alice. In this approach, the proposed protocol allows Alice to learn whether there is any place that she is looking for near her. However, the location-based service (LBS) that tries to help Alice to find nearby places does not learn Alice’s location. Alice can send a request to the LBS database to retrieve nearby places of interest (POIs) without the database becoming aware of what Alice fetched by using private information retrieval (PIR). The common criticism of previous PIR approaches is that they are not practical for smartphones with limited processing power, memory, and wireless bandwidth due to the computational overhead. Therefore, the main focus of this work is to propose a scheme to reduce the computation cost on the client-side to make PIR appropriate and practical for the smartphone environments, and then apply the proposed PIR to LBS applications. We have implemented our protocol in Percy++ to evaluate its performance over a commercial-grade database of POIs. Our implementation results demonstrate that our approach has faster decode and retrieve time for the nearby POIs on smartphones compared with current similar work.

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Big data can be considered to be at the forefront of the present and future research activities. The volume of data needing to be processed is growing dramatically in both velocity and variety. In response, many big data technologies have emerged to tackle the challenges of collecting, processing and storing such large-scale datasets. High-performance computing (HPC) is a technology that is used to perform computations as fast as possible. This is achieved by integrating heterogeneous hardware and crafting software and algorithms to exploit the parallelism provided by HPC. The performance capabilities afforded by HPC have made it an attractive environment for supporting scientific workflows and big data computing. This has led to a convergence of the HPC and big data fields.
However, big data applications usually do not fully exploit the performance available in HPC clusters. This is so due to such applications being written in high-level programming languages and does not provide support for exploiting parallelism as do other parallel programming models.
The objective of this research paper is to enhance the performance of big data applications on HPC clusters without sacrificing the power consumption of HPC. This can be achieved by building a parallel HPC-based Resource Management System to exploit the capabilities of HPC resources efficiently.

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Metal (silver)-Assisted Chemical Etching (MACE) method is used to fabricate silicon nanostructures like silicon nanowires (SiNWs) and silicon nanocones (SiNCs). The morphological characterization of fabricated SiNWs has shown that 5 minutes is the optimal time of silver deposition on silicon substrate. Silicon nanocones (SiNCs) were also fabricated by etching vertical SiNWs with a AgNO3=HF=H2O2 solution. The optical and electrical properties of SiNWs and SiNCs are analyzed and compared with those of the bulk silicon. The fabricated SiNWs (SiNCs) reduce the surface reflectance and the sheet resistance down to 6% (3%) and 9.143 /sq (6.997 /sq) respectively.

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Our work demonstrates how to use contemporary software tools on older or “legacy” robots while keeping compatibility with the original control, tools, and calibration procedures. This is done by implementing a lightweight middle-ware called MDS-Ach connected directly to the hardware communications layer of the robot’s control system. The MDS-Ach middle-ware, which relies on the x-Ach methodology, was specifically designed for Xitome Mobile Dexterous Social (MDS) Robot which was released in 2008. The MDS Robot is actively used in multiple research facilities including the United States Naval Research Laboratory. This middle-ware gives the MDS Robot the bleeding edge software capabilities of today’s robot by implementing the x-Ach real-time processes based computer control architecture. MDS-Ach controls the robot over its low level hardware communications interface (CAN-Bus). This communication controlled and implemented by a real-time daemon process. Controllers communicate with the real-time daemon via a ring buffer shared memory with network capabilities. The ring buffer shared memory is a “first-in-last-out” and is non-head-of-line blocking. All of the latter ensure non-blocking reading and writing of the latest data even while newer data is being added to the buffer. The UDP and TCP protocols can be implemented depending on reliability and timing requirements. Secure communication between networked controllers is implemented via tunneling over SSH if needed. The MDS-Ach middle-ware is designed to allow for simple and easy development with modern robotic tools while adding accessibility and usability to our non-hardware-focused partners. We present an implementation of real-time collision avoidance and a robust inverse kinematics solution within the MDS-Ach system. We include detailed examples of collision avoidance, inverse kinematics implementation, and the software architecture and tools.

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This paper deals with the theoretical aspect of bat echolocation and bionics, and image processing-based target recognition and identification methods. The state estimation methods utilizing the linear rustic filters such as fixed gain and Kalman filters are studied and implemented for echolocation bionics for estimating the LOS distance. A complete mathematical modeling and simulation of bat dynamics and its prey are presented upon which the relative LOS distance is reconstructed with state estimators and less RMS errors. Also, target recognition and identification using Optical, IR Digital Night Vision and Thermal camera is studied and implemented at different environmental conditions to demonstrate the superiority of thermal camera.

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Just as electricity has an essential role in our lives, the internet network and especially web services have become of vital importance nowadays. Without security service layers, apparently small things like checking a child’s school schedule on web may turn the daily routine into a nightmare. Web services users are still required to use many combinations of usernames and passwords. Despite technologically advances that bring many benefits to those owning top of range smartphones, complex combinations of identifiers and passwords are still required for basic security. Top tier smart mobile phones also add device-specific vulnerabilities to the risk of misuse or may expose sensitive data like biometrics. To meet users’ expectations, authentication systems must be safe, fast, efficient, intuitive and easy to use, especially on mobile phones. User satisfaction, reduced fraudulent authentication issues, increased security, reduced management costs, regulatory compliance are main goals for the new advanced web technologies systems. This paper presents some real-time multi-factor authentication methods that uses voice calls to communicate random passwords to registered users. The ultimate goal is to relieve web service users from the stress of memorizing complex combinations, or copying text strings for user identifiers and passwords from paper or external memory devices like mobile phones. The new features are presented for a web service after migration from the traditional authentication system to the one with the proposed new method. This work is an extension of the paper entitled “Securing Web Accounts by Graphical Password and Voice Notification” published in 2018 IEEE International Conference on Engineering, Technology and Innovation (ICEITMC).

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In this paper, we propose a procedure of interactive multi-objective reinforcement learning for multi-step decision problems based on the preference of a decision maker. The proposed method is constructed based on the multi-objective reinforcement learning which is applied to multi-step multi-objective optimization problems. The existing literature related to the multi-objective reinforcement learning indicate that the Hypervolume is often effective to select an action from the Pareto optimal solutions instead of determining the weight of the evaluation for each objective. The experimental result using several benchmarks indicate that the proposed procedure of interactive multi-objective reinforcement learning can discover a certain action which is preferred by the decision maker through interactive.

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This paper investigates the methods of optimal design construction for step-stress accelerated life testing (ALT) when a Cox’s hazards model is adopted with either a linear or a quadratic baseline hazard function. We discuss multiple step-stress plans for time-censored ALT experiments. The maximum likelihood method is utilized for estimating the model parameters. The information matrices have been derived for both models. The optimal stress-changing times and optimal stress levels are determined simultaneously under three different optimality criteria. In order to demonstrate the performance of the resulting designs, a simulation procedure is also provided. The efficiencies of our resulting optimal three-step-stress ALT plans are compared with their competitors using both practical examples and a simulation study. The efficiency comparison results have shown that the three-step-stress designs obtained with two optimal stress changing times and an optimal middle stress level are most efficient, compared to the corresponding optimal two-step-stress designs and to the optimal three-step-stress designs with a conveniently chosen middle stress. Furthermore, the efficient gains are most significant for hazard rate prediction for both cases when either a linear or a quadratic baseline hazard is assumed. Additionally, such efficiency gain is much greater for the case when the baseline function being quadratic than the case when that being simple linear.

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The paper focused on the implementation of fuzzy logic technology for improved Wideband Code Division Multiple Access (WCDMA) network using selected Key Performance Indicators (KPIs). Empirical and analytical methods were principally deployed for the study analyses. Empirical analyses were conducted on two designated networks which are MTN and AIRTEL observed with high network traffic to evaluate their network performances using the selected KPIs. Analytical method was further deployed to improve on the observed limited performance. Five (5) geographical locations within Owerri metropolis were selected for the measurements due to the perceived high density from end users; they include Aba road, FUTO road, Onitsha road, Orlu road and Wetheral road. Selected KPIs include Receive Signal Level (RXLEV), Call Setup Success Rate (CSSR), Call Drop Rate (CDR) and Call Completion Success Rate (CCSR) were used to evaluate the various performance characteristics of the networks based on the QoS. Results obtained from the field measurements computed using the selected KPIs could not meet up with any of the Nigeria Communication Commission (NCC) thresholds. A proposed Fuzzy Logic technique was introduced to the system while varying the congestion load characteristics for different environments using the following parameters; mean bit rate, mean burst rate, network statistics and retainability. An average of 10.2% increase in the system throughput was observed from the proposed system over the existing system.

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There exists a profound difficulty of communication between the people that works in the EMC area in circuit terms and the people that works in field terms.
In this paper we show that when the matter is predominantly distributed along a certain direction in space, as for transmission lines, the electromagnetic field can be divided in two modes, each of them with two degrees of freedom, that are practically independent: a longitudinal TM (transverse magnetic) mode and a transversal TE (transverse electric) mode. We also show that two degrees of freedom of the longitudinal mode are the ones that are described by circuit’s theory.
This formulation is based on the observation that, when the matter is macroscopically described by constitutive laws, the electromagnetic field within the matter can be fully characterized in terms of the potential fields, in total four degrees of freedom.
Using the above formulation, we put forward a generalized formulation of the coupling of an external electromagnetic field to a transmission line, valid in any time scale.
We apply the above concepts to study, in a common theoretical framework, the iconic case of the conducted and radiated interferences on a transmission line, and we show that:
1-Differently than what is normally assumed in standard transmission-line theory, the normal operation mode and the internally-produced electromagnetic field are predominantly a longitudinal TM mode;
2-The longitudinal mode is affected by both the conducted disturbances and the radiated disturbances; while
3- The transverse mode is affected only by the radiated disturbances.
Then, only for systems where the longitudinal mode is predominant, and, the longitudinal and the transversal modes are practically decoupled, EMI can be simulated using circuit simulation software’s.
Also, to further illustrate the interpretation power of this formulation, we present some other application examples.

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As all other laws of the growth in computing, the growth of computing performance also shows a ”logistic curve”-like behavior, rather than an unlimited exponential growth. The stalling of the single-processor performance experienced nearly two decades ago forced computer experts to look for alternative methods, mainly for some kind of parallelization. Solving the task needs different parallelization methods, and the wide range of those distributed systems limits the computing performance in very different ways. Some general limitations are shortly discussed, and a (by intention strongly simplified) general model of performance of parallelized systems is introduced. The model enables to highlight bottlenecks of parallelized systems of different kind and with the published performance data enables to predict performance limits of strongly parallelized systems like large scale supercomputers and neural networks. Some alternative solution possibilities of increasing computing performance are also discussed.

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Low contrast images degrade the performance of image processing system. To solve the issue, plenty of image enhancement methods have been proposed. But the methods work properly on the fixed environment or specific images. The methods dependent on fixed image conditions cannot perform image enhancement properly and perspective of smart device users, algorithms including iterative calculations are inconvenient for users. To avoid these issues, we propose a locally adaptive contrast enhancement method using CNN and simple reflection model. The experimental results show that the proposed method reduces over-enhancement, while recovering the details of the low contrast regions.

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Zirconium trisulfide ZrS3 is a representative of transition metal polysulfides containing sulfur as S–1 in polysulfide, usually disulfide S22– groups. Semiconductive zirconium trisulfide which absorbs visible light near UV edge was considered as a possible photocatalyst. We experimentally studied photodecoloration of methyl orange in presence of ZrS3. It was shown for the first time that crystalline ZrS3 strongly deepens photodegradation reaction, and in one case the methylene orange conversion reached almost 100%. The rates of degradation curves were associated with the ZrS3 samples morphology; the best result revealed for microribbons ZrS3 synthesized at 650°C.

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This work extends the development of the nonuniform Parallel Digital Ramp Pulse Position Modulation Analog-to-Digital Converter (PDRADC) architecture. The continuous to discrete transform of the PDRADC is achieved by partitioning the signal amplitude axis into P nonoverlapping partitions that sample the analog input at input signal driven instances. Each partition contains L uniform levels with different quantization step sizes such that the dynamic range of the partitions are related as a geometric series. It is shown that this new architecture satisfies the Nyquist requirement on average (Beutler’s condition) and results in a random additive sampling architecture that is alias free (Shapiro- Silverman condition). Additionally, it is shown that the geometric partitioning causes the signal-to-quantization noise ratio (SQNR) to remain approximately constant. A comprehensive design paradigm is presented, including circuits to affect the desired response, the format of the encoded digital samples and the corresponding transformation to determine the equivalent analog voltage. Lastly, although the thrust of this paper is not reconstruction techniques, reconstruction is, nevertheless, compulsory, and recovery and reconstruction is demonstrated through simulations.

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Chronic diseases such as heart disease, cancer, diabetes, and asthma continue to increase in the general public within the modern era. With careful observation of the symptoms potential diseases may be detected early and managed properly. For that to happen, the awareness of the symptoms and proper knowledge about the diseases may be needed for each patient. To acquire such knowledge, patients may need to gather essential health information from a variety of sources such as the Internet, articles, or some type of e-learning systems. However, the amount of available information, often too much, which discourages patients to continue. In response to such scenarios, we propose an approach that delivers only the relevant information that is specific to each patient’s condition. In our approach, we utilized observed symptoms and vital signs to identify potential diseases of a patient. As they use the system, their profile may be constructed to deliver patient-specific set of learning materials called a study plan. To monitor and promote their study, we developed a mobile application that allows patients to view their study plan(s) and to study the customized learning materials. Such customized learning allows patients to take control of their symptoms and potential diseases, which eventually helps them to improve their outcomes as a result.

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This study proposes robot-assisted posture emulation for visually impaired children. The motor of a small robot (low torque) can be controlled using our palms. A user does not risk injury when the robotic hand is directly touched. The dimensions of the body of a commercially available small robot are different from those of a person. We adjusted the length of the upper arm to easily distinguish the movements of the upper and lower limbs. Adults and children were requested to perceive the robot’s movements through touch and imitate its action. The study demonstrated that visually impaired subjects enjoyed playing with the robot and the frequency of body movements increased in robot-assisted guidance. The majority of the children could identify the main posture and imitate it. The scoring of continuous movement is medium. A stand-alone concept design was proposed. The design can present the main actions of the upper body and prevent body dumping when touched. Main torso and hand movements can reveal the body language of most users.

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The presence of atmospheric hazards in confined space can contribute towards atmospheric hazards accidents that threaten the worker safety and industry progress. To avoid this, the environment needs to be observed. The air sample can be monitored using the integration of electronic nose (e-nose) and mobile robot. Current technology to monitor the atmospheric hazards is applied before entering confined spaces called pre-entry by using a gas detector. This work aims to develop an instrument to assist workers during pre-entry for atmosphere testing. The developed instrument using specific sensor arrays which were identified based on main hazardous gasses effective value. The instrument utilizes multivariate statistical analysis that is Principal Component Analysis (PCA) for discriminate the different concentrations of gases. The Support Vector Machine (SVM) and Artificial Neural Network (ANN) that is Radial Basis Function Neural Network (RBFNN) are used to classify the acquired data from the air sample. This will increase the instrument capability while the portability will minimize the size and operational complexity as well as increase user friendliness. The instrument was successfully developed, tested and calibrated using fixed concentrations of gases samples. The results proved that the developed instrument is able to discriminate an air sample using PCA with total variation for 99.42%, while the classifier success rate for SVM and RBFNN indicates at 99.28% for train performance and 98.33% for test performance. This will contribute significantly to acquiring a new and alternative method of using the instrument for monitoring the atmospheric hazards in confined space.

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For mission-critical and time-sensitive navigation of autonomous vehicles, controller design must exhibit excellent tracking performance with respect to the speed of convergence to reference command and steady-state accuracy. In this article, a novel design integration of the neural network with the traditional control system is proposed to adaptively obtain optimized controller parameters resulting in improved transient and steady-state performance of motion and position control of autonomous vehicles. Application of the proposed intelligent control scheme to mobile robot navigation was presented for an eight-shaped trajectory by optimizing a Lyapunov-based nonlinear controller. Furthermore, a Linear Quadratic Regulator-based controller was optimized based on the proposed strategy to control the pitch and yaw angles of a 2-Degree-of –Freedom helicopter. The simulation results showed that the proposed scheme outperforms the traditional controllers in terms of the speed of convergence to the desired trajectory and overall error minimization.

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An Orthogonal Frequency Division Multiplexing (OFDM) system with Quadrature Phase Shift Keying (QPSK) mapper is considered. A novel low-complexity Tone Reservation (TR) technique is proposed for reduction of Peak-to-Average Power Ratio (PAPR) of the system. The technique is easy-to-implement and minimizes the search space of phases of reserved tones in the system. The ability of PAPR reduction of this proposed TR technique is assessed and compared with conventional TR technique that uses Pseudo Noise (PN) sequences to determine phases of reserved tones. The simulation results illustrate that the proposed TR technique is nearly the same as that of the conventional TR technique in terms of PAPR reduction capability but with reduced complexity. The Bit Error Rate (BER) performance of QPSK-OFDM system with the novel TR scheme over frequency non-selective Rayleigh fading channel is also determined and illustrated.

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Trusted systems are becoming more integrated into everyday life. Security and reliability are at the forefront of trusted system design and are often directed at hardware-only solutions, especially for safety critical systems. This is because hardware has a well-established process for achieving strong, precise, and reliable systems. These attributes have been achieved in the area of safety critical systems through the use of consistent and repeatable development processes, and a standardized metric for measuring reliability. However, due to the increase in complexity of systems and the looming end of Moore’s Law, software is being incorporated more into the design of these trusted systems. Unfortunately, software typically uses agile development in modern design and uses unreliable metrics for illustrating reliability. This does not make it suitable for safety-critical applications or for total system reliability in mixed hardware/software systems. Therefore, a comprehensive process of systems development needs to be utilized to allow for total system specification at the beginning and a comparable reliability metric in the end which covers software and hardware. Henceforth, we discuss an initial solution to these problems, leading to the establishment of a development process that allows for the proven correctness of a system specification via formal methods. This process also establishes a testing and error reporting process to allow software to be represented in a way that allows the application of reliability metrics similar to those used for hardware.

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Robotic catching of thrown objects is one of the common robotic tasks, which is explored in a number of papers. This task includes subtask of tracking and forecasting the trajectory of the thrown object. Here we propose an algorithm for estimating future trajectory based on video signal from two cameras. Most of existing implementations use deterministic trajectory prediction and several are based on machine learning. We propose a combined forecasting algorithm where the deterministic motion model for each trajectory is generated via the genetic programming algorithm. Object trajectory is extracted from video sequence by the image processing algorithm, which include Canny edge detection, Random Sample Consensus circle recognition and stereo triangulation. After that rajectory is forecasted using proposed method. Numerical experiments with real trajectories of the thrown tennis ball show that the algorithm is able to forecast the trajectory accurately.

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In this paper, behavioral approach has been adopted for the calculation of total power losses that has been further used to derive an analytical model for the conduction and switching losses in a boost Power Factor Correction (PFC) stage of an On-board Charger (OBC). Detailed investigation of power losses can help in finding out ways to improve efficiency and for this purpose, commutation-speed based methodology has been used to split total power losses into their root causes. This gives opportunity to find the impact that an individual part creates on total losses which can serve as a starting point for efficiency improvement. For the analysis, two devices (IGBT with Si diode and IGBT with SiC diode) are used in the considered topology of PFC and a reduction of 40% was calculated when SiC diode was used instead of Si with the same IGBT. Hence it was found that the implemented method proves to be significantly useful in the optimization of efficiency.

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The task of optimal path planning for drilling tool with numerical control is considered. Such tools are used in the production of printed circuit boards. The algorithm modification of level-by-level route construction for the approximate solution of the traveling salesman problem is discussed. Bypass objects can be specified either as a table of distances or values represented by a symmetric matrix, or as Cartesian coordinates (in applied cases of using numerically controlled equipment). The algorithm was tested on many different examples. As a result of the calculations performed for examples from the TSPLIB library (defined through a full distance matrix or Cartesian coordinates) with a dimension of up to 100 cities, the ability of the algorithm to construct the optimal route was confirmed. For examples from other sources or for artificially constructed ones (up to 130 objects), in the testing of the algorithm, the declared record values of the route minimum length were also achieved or improved.

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Modern automobiles have been turning more and more into wireless sensor and communication networks. Accordingly, the number of radio systems is steadily increasing. Due to strict safety requirements, these radio systems need to be tested extensively for functionality and reliability, especially under poor radio channel conditions. Beside the large electrical size of cars at frequencies of mobile communication services, access to the antennas imposes challenges for testing, due to an increasingly high integration of the antennas with frontends and digital signal processing. This paper proposes an over-the-air testing procedure for automotive radio systems on the basis of the wireless communication standard Long Term Evolution (LTE). A method to derive the radiation patterns of automotive antennas from reference signals in the LTE downlink scheme without requiring any access to the analogue RF feed point is proposed. A comparison of the LTE approach with the usual antenna measurement techniques shows good agreement. As a logical step from the antenna towards a complete wireless link, a concept of spatially distributed channel emulation on the basis of Software Defined Radio (SDR) modules is proposed, aiming at the emulation of essential multipath features of the wireless channel. RF measurements of the channel transfer function as well as by over-the-air end-to-end tests prove this approach to be a cost-efficient alternative to commercial channel emulators.

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TSN is an attractive solution for latency-critical frame transmission built upon IEEE 802 architecture. Traffic scheduling and shaping in TSN aim to achieve bounded low latency and zero congestion loss. However, the most widespread solution (i.e. Time-Aware Shaper) requires a networkwide precision clock reference and only targets on cyclical traffic flows. This paper focuses on the performance evaluation of the ATS, which applies shaping algorithm to any flows and requires no clock reference. Simulations are proposed for evaluation and comparison. Metrics including end-to-end delay, buffer usage and frame loss rate are collected to assess the shaping performance. Results show that ATS achieves effective traffic shaping and switching without synchronous mechanisms, while there is an evident trade-off for using these specific algorithms.

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Climatic changes have a significant impact on many real life processes. Climacteric position of Albania makes precipitations and water inflows in HPP the main variables influencing the amount of electric energy produced in the country. Taking into account their volatility it has considerably increased the need of using hybrid models to improve the quality of predictions. After a detailed analysis of the time series components, we develop a group of hybrid models and propose modifications to increase the accuracy in prediction. Among the contributions of this work is the challenge to choose between hybrid models presented earlier in literature and the modified version according to the nature of data. The final decision on the most accurate model is made based on many goodness of fit test. This study suggest that an accurate selection of the forecasting techniques increases significantly the quality of forecast on precipitations and water inflow data.

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Climatic changes have a significant impact on many real life processes. Climacteric position of Albania makes precipitations and water inflows in HPP the main variables influencing the amount of electric energy produced in the country. Taking into account their volatility it has considerably increased the need of using hybrid models to improve the quality of predictions. After a detailed analysis of the time series components, we develop a group of hybrid models and propose modifications to increase the accuracy in prediction. Among the contributions of this work is the challenge to choose between hybrid models presented earlier in literature and the modified version according to the nature of data. The final decision on the most accurate model is made based on many goodness of fit test. This study suggest that an accurate selection of the forecasting techniques increases significantly the quality of forecast on precipitations and water inflow data.

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Network security challenges due to nearly limitless internet connectivity, platform limitations, ubiquitous nodal mobility and huge data transactions is burgeoning by the day and the need for transcend Internet of Things (IoT) based cloud security authentication protocols is on an exponential rise. Even though many secure classic layered security mechanisms are available for implementation, they cannot be applied on IoT devices because of the huge energy that they consume. The essence of the paper is an attempt to revisit the existing IoT based security authentication protocols operating in the Application Layer (AL) , AL being the end user’s actual service provider. This gateway to the outside world definitely demands stringent and safe data handling and processing. The main objective of the paper is to highlight the positives of the AL protocols and also take a note of the drawbacks in terms of security and defensive measures. The author intends to support the users with information sufficient enough to decide on the type of protocol based on the application. The paper helps the future researchers to have a comparative analysis of each AL protocol’s performance and further work on effective improvised defensive measures to tackle the threat-prone IoT environment even better. The paper discusses the architecture implementations, security provisions as well the pros and cons of certain avowed AL protocols currently being used in an IoT environment. Furthermore, the vulnerabilities and possible open issues currently encountered in the AL contribute valuably to the paper since they unravel the path to future research opportunities for secure interconnection of communicating devices.

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The 5G is the fifth generation of mobile broadband, cellular technologies, and networks that promises a major change in mobility by evolving connected business realities. In such an emerging environment, reliable Service Level Agreements (SLA) and anticipation of breaches of Service Level Objectives (SLO) become compulsory. Thus, guaranteeing the required service quality, while also ensuring efficient recourse allocation becomes a challenge. In addition, 5G networks are expected to provide diverse Quality of Service (QoS) guarantees for a wide range of services, applications and users with a variety of requirements. However, there is an increased difficulty in translating user-friendly business terms into resource-specific monitoring attributes that can be used to manage resources in the 5G core network. To address these gaps, an SLA management framework, enabling QoS provisioning is introduced. The aforementioned framework will be supported by an adaptive monitoring algorithm, which removes the static time interval used in the monitoring system, in order to provide highly accurate information in real time, without the produce of unnecessary traffic to the network. The proposed architecture also incorporates a recommendation mechanism to determine the significance of various QoS parameters in order to ensure that relevant QoS metrics are included in the SLAs, using enriched metadata information from a Network Function Virtualization (NFV) Catalogue.

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