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This paper presents novel loss quantization of reflectarray elements based on organic substrate materials. Three differently composed substrate materials derived from recycled materials have been characterized for their dielectric properties using a broadband analysis technique. The materials show low dielectric permittivity values of 1.81, 1.62 and 1.84 for X-band frequency range. In order to estimate the reflection loss of for the three substrates a mathematical relation has been established using empirical data generated by computer simulated models. The reliability of the proposed model has been established by simulation and fabrication of unit reflectarray rectangular patch elements on three proposed substrate substrates. A broadband frequency response has been depicted by scattering parameter analysis of unit elements with 10% fractional bandwidth of 312, 340 and 207 MHz for RCP50, RCR75 and RNP50 substrate respectively. [ABSTRACT FROM AUTHOR]

This paper presents the characteristic MIMO 2x4 antenna for 5G communication system. The proposed antenna works at 28 GHz and simulated by using CST simulation software. The antenna uses RT Duroid 5880 substrate with dielectric constant of 2.2. The MIMO antenna consists of eight elements with rectangular patches and inset feeding. Thedimension of patch (Wp x Lp) is 6 mm x 8 mm. There are three (3) antenna configurations derived in this paper such as; single element, 1x4 elements and 2x4 elements. The MIMO 1x4 elements antenna configuration is designed based on the single element antenna with the distance between center to center elements antennas of 5 mm. The MIMO 2x4 antenna is formed from the MIMO 1x4 element configuration with the opposite direction. The 2x4 element antenna, a distance between opposite antenna elements is 10 mm. From the simulation results, it is shown that by increasing the number elements of antenna affect to the directivity and the return loss. Antenna with 2x4 elements has 14 dBi of directivity with the return loss of -19 dB. While antenna with 1x4 elements, the directivity obtained is 14.3 dBi with return loss of -18 dB. [ABSTRACT FROM AUTHOR]

Within the rapidly evolving landscape of wireless communication technologies, this scientific paper delves into an innovative approach by exploring the integration of the Bluetooth frequency band into a circular antenna design. Leveraging the capabilities of metamaterials. The Bluetooth frequency band a cornerstone for short-range communications, takes center stage in our study. Traditionally associated with wireless connectivity in diverse applications, its integration into a circular antenna structure opens up new avenues for optimizing performance and functionality. Our research aims to not only enhance the efficiency of short-range communication systems but also contribute to the broader discourse on antenna design evolution. The computer simulation technology (CST) studio suite is utilized to show the recommended antenna design. By scrutinizing the symbiotic relationship between the Bluetooth frequency band and the circular antenna augmented with metamaterial, our study endeavors to push the boundaries of current design paradigms. We believe that this exploration will not only address the contemporary challenges associated with wireless communication but also pave the way for the development of more sophisticated, adaptable, and compact devices in the ever-expanding realm of telecommunications. [ABSTRACT FROM AUTHOR]

For the single spectrum image could not fully express the target feature information, this paper proposed a multispectral image fusion method based on non-subsample contourlet transform (NSCT). For the low frequency coefficients decomposed, fourth-order correlation coefficient is used to calculate the correlation between each low frequency coefficients, averaging fusion for the higher correlation coefficient, weight phase congruency fusion for the low correlation coefficient. For high frequency coefficients, Gaussian weight sum modified Laplace method is used for fusing, to retain more local structure details. Simulation results show that the method effectively retain the image structure information and more local details, and increase the image contrast. [ABSTRACT FROM AUTHOR]

In recent years, the study of complex networks has been a focus subject of technology fields. In this paper, we consider the adaptive control and synchronization of uncertain complex networks. By using the adaptive control techniques with the linear feedback updated law and the well-known LaSalle invariant principle on dynamical system theory, some simple yet generic criteria are derived. Furthermore, the result is applied to typical chaotic cellular neural networks (CNN). Finally, numerical simulations are presented to demonstrate the feasibility and effectiveness of the proposed techniques. [ABSTRACT FROM AUTHOR]

This paper proposes two strategies for satisfying the quorum of two colliding meetings through host-to-host negotiation scheme. The strategy is to let a member attend the other meeting under the condition that the group decision regarding the schedule is not changed and meeting quorum is fulfilled, namely the unassignment strategy. Another strategy is to substitute the absent personnel member in order to keep the number of attendees above the quorum, namely the substitution strategy. This paper adapts a mechanism design approach, which is Clarke Tax Mechanism, in order to implement incentive compatibility and individual rationality principle in meeting scheduling. By using the unassignment strategy and substitution strategy, the meetings can still be held simultaneously according to the schedule without the need for rescheduling. This paper shows the simulation result of using the strategies within some scenarios. It demonstrates that the number of meeting failures caused by unsatisfied quorum can be reduced with host-to-host negotiation. [ABSTRACT FROM AUTHOR]

Genetic algorithm is a global probability search algorithm developed by simulating the biological natural selection and genetic evolution mechanism and it has excellent global search ability, however, in practical applications, premature convergence occurs easily in the genetic algorithm. This paper proposes an self-adaptive multi-peak immune genetic algorithm (SMIGA) and this algorithm integrates immunity thought in the biology immune system into the evolutionary process of genetic algorithm, uses selfadaptive dynamic vaccination and provides a downtime criterion, the selection strategy of immune vaccine and the construction method of immune operators so as to promote the population develop towards the optimization trend and suppress the degeneracy phenomenon in the optimization by using the feature information in a selective and purposive manner. The simulation experiment shows that the method of this paper can better solve the optimization problem of multi-peak functions, realize global optimum search, overcome the prematurity problem of the antibody population and improve the effectiveness and robustness of optimization. [ABSTRACT FROM AUTHOR]

At present, a good deal of methods for the Maximum Power Point Tracking (MPPT) has been used in engineering applications. However, Matlab simulation proved that they were difficult to harmonize the stability and speed ability of system. In addition, in order to maximize the use of PV panels 'power, the paper focused on aneonatalalgorithm for Maximum Power Point Tracking (MPPT). Based on the algorithm, this paper designed an improved and feasible variable step perturbation and observation method which well alleviated the conflict that the maximum power point tracking could not take into account the stability and speed of response efficiently. [ABSTRACT FROM AUTHOR]

Image compression is to compress the redundancy between the pixels as much as possible by using the correlation between the neighborhood pixels so as to reduce the transmission bandwidth and the storage space. This paper applies the integration of wavelet analysis and artificial neural network in the image compression, discusses its performance in the image compression theoretically, analyzes the multi- resolution analysis thought, constructs a wavelet neural network model which is used in the improved image compression and gives the corresponding algorithm. Only the weight in the output layer of the wavelet neural network needs training while the weight of the input layer can be determined according to the relationship between the interval of the sampling points and the interval of the compactly-supported intervals. Once determined, training is unnecessary, in this way, it accelerates the training speed of the wavelet neural network and solves the problem that it is difficult to determine the nodes of the hidden layer in the traditional neural network. The computer simulation experiment shows that the algorithm of this paper has more excellent compression effect than the traditional neural network method. [ABSTRACT FROM AUTHOR]

This paper presents a performance evaluation of nonlinear filtering with Interacting Multiple Model (IMM) algorithm for implementation on Indonesian coastal radar target tracking system. On this radar, target motion is modeled using Cartesian coordinate but target position measurements are provided in polar coordinate (range and azimuth). For this implementation, we investigated two types of nonlinear filtering, Converted Measurement Kalman Filter (CMKF) and Unscented Kalman Filter (UKF). IMM algorithm is used to anticipate target motion uncertainty. Many simulations on radar target tracking are developed under assumption that noise characteristic is known. In this paper, the performance of IMMCMKF and IMM-UKF is evaluated for condition that radar doesn't know noise characteristic and there is mismatch on noise modeling. Results from simulation show that IMM-CMKF has better performance than IMM-UKF when tracking maneuvering trajectory. Results also show that IMM-CMKF is more robust than IMM-UKF when there is mismatch on noise modeling. [ABSTRACT FROM AUTHOR]

The depletion of conventional energy sources and global warming has raised worldwide awareness on the usage of renewable energy sources particularly solar photovoltaic (PV). Renewable energy sources are non-polluting sources which can meet energy demands without causing any environmental issues. For standalone PV systems, a low conversion efficiency of the solar panel and high installation cost due to storage elements are the two primary constraints that limit the widespread use of this system. As the size of the system increases, the demand for a highly efficient tracking and charging system is very crucial. Direct charging of battery with PV module will results in loss of capacity or premature battery degradation. Furthermore, most of the available energy generated by the PV module or array will be wasted if proper tracking technique is not employed. As a result, more PV panels need to be installed to provide the same output power capacity. This paper presents selection, design and simulation of maximum power point tracker (MPPT) and battery charge controller for standalone Photovoltaic (PV) system. Contributions are made in several aspects of the whole system, including selection of suitable converter, converter design, system simulation, and MPPT algorithm. The proposed system utilizes direct duty cycle technique thus simplifying its control structure. MPPT algorithm based on scanning approach has been applied by sweeping the duty cycle throughout the I-V curve to ensure continuous tracking of the maximum power irrespective of any environmental circumstances. For energy storage, lead acid battery is employed in this work. MATLAB/Simulink® was utilized for simulation studies. Results show that the propose strategy can track the MPPs and charge the battery effectively. [ABSTRACT FROM AUTHOR]

This paper describes a new risk assessment model for application development and its implementation. The model is developed using a Bayesian network and Boehm's software risk principles. The Bayesian network is created after mapping top twenty risks in software projects with interrelationship digraph of risk area category. The probability of risk on the network is analyzed and validated using both numerical simulation and subjective probability from several experts in the field and a team of application developers. After obtaining the Bayesian network model, risk exposure is calculated using Boehm's risk principles. Finally, the implementation of the proposed model in a government institution is shown as a real case illustration. [ABSTRACT FROM AUTHOR]

This paper develops an adaptive control coordination scheme for power system stabilizers (PSSs) to improve the oscillation damping and dynamic performance of interconnected multimachine power system. The scheme was based on the use of a neural network which identifies online the optimal controller parameters. The inputs to the neural network include the active and reactive- power of the synchronous generators which represent the power loading on the system and elements of the reduced nodal impedance matrix for representing the power system configuration. The outputs of the neural network were the parameters of the PSSs which lead to optimal oscillation damping for the prevailing system configuration and operating condition. For a representative power system, the neural network has been trained and tested for a wide range of credible operating conditions and contingencies. Both eigenvalue calculations and time-domain simulations were used in the testing and verification of the performance of the neural network-based stabilizer. [ABSTRACT FROM AUTHOR]

An adaptive radical basis function (RBF) neural network PID control scheme for X-Y position table is proposed by the paper. Firstly, X-Y position table model is established, controller based on neutral network is used to learn adaptive and compensate uncertainty model of X-Y position table, neutral network is used to study model. PID neural network controller base on augmented variable method is designed. PID controller is used as assistant direction error controller, neural network parameters base on stochastic gradient algorithm can be adjust adaptive on line. The simulation results show that the presented controller has important engineering value. [ABSTRACT FROM AUTHOR]

Traveling-wave-based fault location in electrical distribution systems is an important safeguard for the distribution network reliability. The effectiveness of the methods is verified directly in power grid in the early stages, while different fault types can't appear in a short time. And normal dynamic physical simulation cannot meet the teaching demand either because of the limitation of transmission line model and other factors. So PSCAD/EMTDC and MATLAB are used to illustrate the the fault location methods in this paper, which can promote the traveling-wave-based fault-location technology. Meanwhile, the traveling-wave-based fault-location method based on characteristic frequencies is analyzed in this paper. [ABSTRACT FROM AUTHOR]

In this paper, novel device discovery approaches for the cluster head rotation, which is a state-ofthe- art method for the Device-to-Device communication, are proposed. The device discovery is the process to detect and to include new devices in the Device-to-Device communication. The proposed device discovery is aimed to attain energy efficiency for the communication devices. We propose two schemes for the device discovery: eNB-assisted and independent device discovery. Compared to previous work, the proposed device discovery is utilizing the cluster head rotation method, to achieve better energy efficiency. In this work, several simulations were performed and discussed for both schemes. In the first simulation, the device energy consumption is examined. After that, the number of devices that get rejected is studied. The device discovery processes in multi cluster head scenario, which is cluster head rotation, are examined in this paper. The result of the simulation shows that eNB-assisted device discovery can provide better energy efficiency. Also, the number of rejected devices of the eNB-assisted device discovery is slightly lower than independent device discovery. [ABSTRACT FROM AUTHOR]

Wireless sensor network (WSN) is self-organizing network; it consists of a large number of sensor nodes with perception, calculation ability and communication ability. Generally, the floor, walls or people moving has an effect on indoor localization, so it will result in multi-path phenomena and decrease signal strength; also the received signal strength indicator (RSSI) is unable to gain higher accuracy of positioning. In order to improve the WSN positioning accuracy in indoor condition, in this paper, we firstly propose krill swarm algorithm used for WSN localization. We detailed analyze the multilateral measurement method in range-free distance vector-hop (DV-hop) localization algorithm. The position problem can be transformed into a global optimization problem. Then, we adequately utilize the advantage of calculating optimization problem and apply the krill swarm algorithm into the stage of estimating unknown node coordinates in DV-hop algorithm to realize localization. Finally, the simulation experience results show that the localization with krill swarm algorithm has an obviously higher positioning precision and accuracy stability with different anchor node proportion and nodes. [ABSTRACT FROM AUTHOR]

Antennas are generally contructed from metallic materials; therefore it is prone to corrosion when installed outdoors. Radome is an important part of an outdoor antenna that serves to protect the antenna from environmental conditions. Radome structure is not expected to have a significant influence on the characteristics of the antenna. Parametric study is generaly applied in finding the optimum antenna dimenssion included radome. A method for guiding a parametric study proses in finding the optimum antenna dimensions has investigated and proposed in this paper. In this study, a method for determining the optimum radome dimension for planar antenna by applying the algorithm Least Mean Error (LME) has investigated. LME algorithm is used to find the optimum dimensions of the radome. The simulation results show that the proposed method can be applied to determine the dimensions of a planar antenna. [ABSTRACT FROM AUTHOR]

Copyright of Telkomnika is the property of Department of Electrical Engineering, Ahmad Dahlan University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Telkomnika is the property of Department of Electrical Engineering, Ahmad Dahlan University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Telkomnika is the property of Department of Electrical Engineering, Ahmad Dahlan University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Telkomnika is the property of Department of Electrical Engineering, Ahmad Dahlan University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fuel cells are new alternative energy resource that has a great promise for distributed generation and electric vehicle application. However, fuel cells have a slow response due to their slow internal electromechanical and thermodynamic response. To optimize the fuel cell system performance, a fuel cell DC-DC converter with an appropriate controller which can regulate the power flow and automatically adjust the converter output voltage is needed. This paper proposes a new control technique for fuel cell DC-DC power converter. Design of the proposed control method for fuel cell DC-DC power converter is provided. A new approach for converter controllers synthesis based on dynamic evolution control theory is presented. In this paper, synthesis example of boost DC-DC converter is discussed. Performance of the proposed dynamic evolution control under step load variation condition is simulated under Matlab-Simulink environment. Simulation results show that the proposed techniques are capable for controlling fuel cell DCDC converter. [ABSTRACT FROM AUTHOR]

Co-channel interference among Device-to-device (D2D) users is major issue to be solved when utilizing the same frequency bands. Consequently, interference alignment (IA) as an effective interference management approach has been implemented to D2D communications for the frequency sharing. However, the measurement of channel state information (CSI) between transmitter and receiver of a D2D pair and cross-channel state information (C-CSI) among D2D pairs are the major issues that need to be resolved for the implementation of IA from theory to practical. Therefore, in this paper, we propose an effective D2D discovery scheme to overcome this problem, which can measure the CSI and C-CSI based on the discovery messages. Simulation results show that, under perfect conditions, even though the proposed D2D discovery scheme increases the needed time slots to establish D2D communications by 6.2% compared with the conventional D2D discovery without considering IA, it increases the throughput up to 50% than the conventional D2D without considering IA, i.e., it improves the spectrum efficiency. [ABSTRACT FROM AUTHOR]

Cooperative multicell precoding is an attractive way of improving the performance in multicell downlink scenarios especially for terminals at cell edges. Multiple base stations in a given area serve each terminal after precoding, which can coordinate the inter-cell interference and achieve higher performance. Most previous work in the area has focus on centralized precoding which requires gathering all transmitters' channel state information (CSI) at central station (CS) through backhaul and then precoding at CS. However, the requirements on backhaul signaling and computational power scales rapidly in large and dense networks, which usually make such fully centralized approaches impractical. In this paper, we study two practical precoding strategies with only local CSI under a relatively realistic scenario. Performance is finally illustrated through numerical simulations. [ABSTRACT FROM AUTHOR]

Computer methods in biomechanics are computer methods for solving biomechanics problems. Rula, Reba, Niosh, Owas is a method of analyzing work risks due to incorrect posture. Each method uses a worksheet on one posture to analyze risk. For dynamic work, a computer method is needed that can quickly calculate every change in posture. Virtual reality and Kinect as dynamic work analysis methods cannot be carried out preventively. Preventive measures are needed to prevent workers from risks resulting from work. For this reason, computer simulation methods are needed to create work stations and work processes so that they can be carried out preventively. The s-task simulation builder (S-TSB) framework provides a dynamic work analysis solution using simulation. The three processes carried out include surveying, creating simulations and processing posture data. Software validation was tested using the black box analysis method and the results were as expected. The dynamic working model is tested showing results in the form of graphs so it is easy to compare each change. The use of simulation also saves design costs because optimization can simply be done by changing the simulated work station data and/or work process. [ABSTRACT FROM AUTHOR]

In this paper, the effect of the kernel size of Wiener and Gaussian filters on their image restoration qualities has been studied and analyzed. Four sizes of such kernels, namely 3x3, 5x5, 7x7 and 9x9 were simulated. Two different types of noise with zero mean and several variances have been used: Gaussian noise and speckle noise. Several image quality measuring indices have been applied in the computer simulations. In particular, mean absolute error (MAE), mean square error (MSE) and structural similarity (SSIM) index were used. Many images were tested in the simulations; however the results of three of them are shown in this paper. The results show that the Gaussian filter has a superior performance over the Wiener filter for all values of Gaussian and speckle noise variances mainly as it uses the smallest kernel size. To obtain a similar performance in Wiener filtering, a larger kernel size is required which produces much more blur in the output mage. The Wiener filter shows poor performance using the smallest kernel size (3x3) while the Gaussian filter shows the best results in such case. With the Gaussian filter being used, similar results of those obtained with low noise could be obtained in the case of high noise variance but with a higher kernel size. [ABSTRACT FROM AUTHOR]

Despite the adoption of Learning Management Systems (LMS) has been continuously growing in the last decade few, if any, scholars addressed the lack of the interactivity in online learning systems. The requirement for an interactive learning model has been increasingly prominent as content providers realize the importance of personalization of content suits to learners' learning progress. This paper demonstrates the adoption of adaptive learning into existing LMS engine to overcome the limitation of either systems plugins or server specification pertinent to students' psychomotor abilities in computer programming learning. In this regard, the psychomotor is understood as the ability of students to write the program code as correctly as expected. In this study, a web API model that works to run an interpreter based-program code remotely was developed. The web API model can be utilized by LMS so it becomes the solution to the problem. The structure of the web API model has been adapted to the needs of the learning assessment. The implementation of the developed API web model is done in Python and PHP programming languages. The performance test was done by submitting 10 to 100 program codes simultaneously indicated no significant difference to the required resources (CPU usage and memory usage) to run the program code. Furthermore, for response time, the average time needed to run Python and PHP program code is also no significant difference. The average of CPU usage required by the web API to run a Python program code is 0.2058% with 0.5973 seconds as a response time. Meanwhile, to run the PHP program code, the average CPU usage required is 0.8074% with 0.3110 seconds response time. It can be concluded that the web API performance does not overburden the server. [ABSTRACT FROM AUTHOR]

The cognitive radio technology can improve the efficiency of spectrum utilization byproviding dynamic spectrum access to unoccupied frequency bands. Spectrum sensing is one of the key technologies of cognitive radio networks. The spectrum sensing performance of cognitive radio networks will be greatly reduced in the low SNR environment, especially when using energy detection. Because the stochastic resonance system can improve the energy detection system output SNR .To improve the spectrum sensing performance of cognitive radio networks in the low SNR environment, the stochastic resonance of the single-mode nonlinear optical system is applied to spectrum sensing based on the energy detection method in this paper. The simulation results show that in the low SNR environment, the energy detection based on stochastic resonance of the single-mode nonlinear optical system has better performance than traditional energy detection. [ABSTRACT FROM AUTHOR]

In this paper, a new broadband microwave microstrip power limiter is designed and realized. The Power Limiter is based on microstrip technology integrating a Zero Bias commercial Schottky diodes HSMS2820.The power limiter is optimized and validated in two steps. The enhanced and achieved circuit is obtained by concatenating two basic structures. The final circuit was validated into simulation by using ADS solver. Finally this circuit was realized and tested. Simulation and measurement results are in a good agreement. The final circuit achieves a limiting rate of 14 dB with a threshold input power level of 0 dBm until a maximum input power level of 30 dBm. [ABSTRACT FROM AUTHOR]

Current methods of service selection based on quality of service (QoS) usually focus on a single service request at a time, or let the users in a waiting queue wait for Web services when the same functional Web service has more than one requests, and then choose the Web service with the best QoS for the current request according to its own needs. However, there are multiple service requests for the same functional web service at a time in practice and we cannot choose the best service for users every time because of the service's load. This paper aims at solving the Web Services selection for concurrent requests and developing a global optimal selection method for multiple similar service requesters to optimize the system resources. It proposes the improved social cognitive (ISCO) algorithm which uses genetic algorithm for observational learning and uses deviating degree to evaluate the solution. Furthermore, to enhance the efficiency of ISCO, the elite strategy is used in ISCO algorithm. We evaluate performance of the ISCO algorithm and the selection method through simulations. The simulation results demonstrate that the ISCO is valid for optimization problems with discrete data and more effective than ACO and GA. [ABSTRACT FROM AUTHOR]

Currently, the method of optimizing the wavelet neural network with particle swarm plays a certain role in improving the convergence speed and accuracy; however, it is not a good solution for problems of turning into local extrema and poor global search ability. To solve these problems, this paper, based on the particle swarm optimization, puts forward an improved method, which is introducing the chaos mechanism into the algorithm of chaotic particle swarm optimization. Through a series of comparative simulation experiments, it proves that applying this algorithm to optimize the wavelet neural network can successfully solve the problems of turning into local extrema, and improve the convergence speed of the network, in the meantime, reduce the output error and improve the search ability of the algorithm. In general, it helps a lot to improve the overall performance of the wavelet neural network. [ABSTRACT FROM AUTHOR]

A great many problems, such as scalability, mapping data searching, high frequency update of mapping data, arise in the future network resource mapping system for its vast data processing need. Future Network Chord (FN Chord), an algorithm based on Chord and aims at solving the resources identity mapping and searching problem, is put forward by taking advantage of the qualities of scalability, rapid searching speed, high searching efficiency and flexible naming of chord in order to solve this problem. What's more, an extra interest node index table for FN Chord is designed to record the hotspot resource mapping location in the paper. So, the resource searching strategy, which is named as Interest Index Table Future Network Chord (IIT-FN Chord) is proposed to search the resource in the paper. The entropy weight method is used to calculate the node interest level according the interest nodes' resource item online time and visited times and to renew the interest index table. Moreover, probability replacement method is proposed to replace the outdated item on interest index table with new item. Simulation results show that the algorithm can decrease the average searching latency, average searching hops and thus increases the searching efficiency for the resource searching. [ABSTRACT FROM AUTHOR]

A new complex-valued wavelet neural network is proposed in this paper, by introducing a modified complex-valued back propagation algorithm, in which a new error function is to be minimized by the algorithm. The improvement performance is further confirmed by the simulation results, which show that the modified algorithm is simpler than the conventional algorithm, and has better convergence, better stability and faster running speed. [ABSTRACT FROM AUTHOR]

This paper presents another circuit configuration of single-phase hybrid five-level voltage-source inverter obtained from the H-bridge inverter and DC-voltage modules. Some features are achieved by using the proposed inverter configuration such as its modular structure and minimum number of the power devices required to construct the inverter circuits. The proposed five-level inverter circuit is examined through computer simulation using PSIM software. Furthermore, laboratory experimental tests were also performed to verify the prototype of the proposed five-level inverter circuits. The computer simulation and experimental test results shows that the proposed hybrid five-level voltage source inverter works properly to generate a five-level voltage waveform and sinusoidal current with low harmonics contents. [ABSTRACT FROM AUTHOR]

This paper focused on designing a bi-directional beams waveguide slotted antenna at millimetre wave spectrum. Waveguide slotted antenna is known for its highly directional pattern. By having bi-directional pattern, the capacity of system coverage can be expanded. The design is implemented by using antenna slot theory on a waveguide structure. The slotted are made on two wall surfaces and the performance is compared to the slotted on single wall. The two models designs are simulated using Computer Simulation Technology (CST) microwave software. The simulation results show that both models operate at 30 GHz with minimum reflection coefficient of -24.63 and -25.01 dB respectively. The two models achieved a fair high gain at 15.5 dB and 13.3 dB with directional beamwidth of 8.9 degree. The proposed bi-directional beams structure achieved a comparable gain in both directions when compared to the single direction. [ABSTRACT FROM AUTHOR]

This paper presented the design of integrated open loop resonator bandpass filter with notch type antenna for the use in microwave applications. Chebyshev type filter is selected as the filter characteristics and cascaded design with the antenna to produce a single module, Integrated Filter Antenna (IFA). Special feature of the antenna is the implementation of notch on the patch antenna to improve the efficiency. IFA is then simulated in electromagnetic simulation tool, Agilent Advance Design System (ADS) version 2016 and measured using R&S Vector Network Analyzer. It shows that the proposed IFA produced good measured return loss >-30dB with both vertical and horizontal gain of 9.11dBi and 8.01dBi respectively. [ABSTRACT FROM AUTHOR]

In this paper, we suggested two approaches to minimizing the CH packet size by considering the accuracy of prediction of sensed data at the base station. The proposed coding schemes based relative difference (CS-RD) and based the factor of precision (CS-FP) instead of the absolute change method that has been used in recent work. The aim is to enhance the accuracy of prediction data at the base station. Therefore, the performance metric was evaluated in term of the accuracy of prediction data at the base station. Simulation results showed that the proposed approaches performed better in term of the accuracy of prediction data at the base station. Specifically, the distortion percentage and average Absolut error in the CS-RD and CS-FP method decreased by 50% and 88% better than the current new aggregation method (ADATDC). However, our proposed CS-FP showed a low reduction ratio for some states. [ABSTRACT FROM AUTHOR]

This paper proposed a new design of Minkowski Island microstrip antenna fed by proximity coupling with partial ground plane. The design was consisted of two layers of substrate, on the top substrate was the antenna patch and on the bottom substrate was the proximity feed line and the partial ground. At the first stage, the normal square patch antenna was mainly designed. Then, the Minkowski patch antenna was designed using 1st iteration technique and 2nd iteration technique. The Minkowski fractal shape slot was embedded in the center of the patch to form a Minkowski Island patch antenna. Using the Minkowski Island fractal technique, the dimension of the patch can be reduced up to 58.7%. The proximity feed line in this design was used to increase the impedance bandwidth, and from the measurement the impedance bandwidth of the proposed antenna was 240 MHz with return loss of -24.54 dB and VSWR of 1.126. [ABSTRACT FROM AUTHOR]

Microwave sensor is used in various industrial applications and requires highly accurate measurements for material properties. Conventionally, cavity waveguide perturbation, free-space transmission, open-ended coaxial probe, and planar transmission line technique have been used for characterizing materials. However, these planar transmission lines are often large and expensive to build, further restricting their use in many important applications. Thus, this technique is cost effective, easy to manufacture and due to its compact size, it has the potential to produce sensitivity and a high Q-factor for various materials. This paper reviews the common characteristics of planar transmission line and discusses numerous studies about several designs of the microstrip resonator to improve the sensor performance in terms of the sensitivity and accuracy. This technique enables its use for several industrial applications such as agriculture and quality control. It is believed that previous studies would lead to a promising solution of characterizing materials with high sensitivity, particularly in determining a high Qfactor resonator sensor. [ABSTRACT FROM AUTHOR]

This paper presents a method to decrease imprecision and inaccuracy that have the tendency to influence the posture of non-holonomic mobile robot by using the adaptive tuning of universe of discourse. As such, the primary objective of the study is to force the posture error of x(t), y(t) and θ(t) towards zero. Hence, for each step of tuning the fuzzy domain, about 20% of imprecision and inaccuracy had been added automatically into the variable universe fuzzy, while the control input was bound via scaling gain. Furthermore, the simulation results showed that the tuning of universe fuzzy parameters could increase the performance of the system from the aspects of response time and error for steady state through better control of inaccuracy. Besides, the domains of universe fuzzy input [-4,4] and output [0,6] exhibited good performance in inching towards zero values as the steady state error was about 1% for x(t) position, 0.02% for y(t) position, and 0.16% for θ(t) orientation, whereas the posture error in the given reference was about 0.0002% . [ABSTRACT FROM AUTHOR]

This paper proposed the gas for industrial ammonia leak diffusion model and the Gauss method of leakage localization. A set of wireless ammonia leak alarm system is composed of sensor node, network coordinator and host used in the industrial field was developed, the purpose is to reduce the loss of property caused by the leakage of ammonia industry. Using the monitoring system to carry out the ammonia leak location simulation measurement experiment, the result shows that the relative positioning error of the monitoring system is about 12%, which meets the needs of industrial production safety monitoring. Using the wireless sensor network to monitor the concentration of ammonia gas and locate the leakage source, it solves the problems of traditional wired alarm system, such as difficult wiring and weak expansibility, which helps to find the leak timely and provides a reference for the emergency rescue work. [ABSTRACT FROM AUTHOR]

Copyright of Telkomnika is the property of Department of Electrical Engineering, Ahmad Dahlan University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Telkomnika is the property of Department of Electrical Engineering, Ahmad Dahlan University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents how to characterize the quality of multimedia which consists of audio and video that are transmitted in real-time communication through the Internet with limited bandwidth. We developed a methodology of characterizing the multimedia Quality-of-Service (QoS) by measuring network parameters (i.e., bandwidth capacity, packet loss rate (PLR), and end-to-end delay) of testbed network and simulating the audio-video delivery according to the measured network parameters. The analysis of network parameters was aimed to describe the network characteristics. Multimedia QoS was characterized by conducting a simulation using data which was collected from the previous network characterization. A simulation network model was built using OMNet++ representing a delivery of audio-video in real-time while a background traffic was generated to represent a real condition of the network. Apllying the methodology in a network testbed in Indonesia's rural area, the simulation results showed that audio-video could be delivered with accepted level of user satisfaction. [ABSTRACT FROM AUTHOR]

In this paper a two layers microstrip antenna design at 2.45 GHz ISM band with Harmonic rejection filter embedded on the ground plane is presented. The two roger substrates with relative permittivity of 2.2 are separated by an air gap which enhances the antenna gain. The design is simulated using Computer Simulation Technology (CST) Studio Suite 2015. Different aperture couplings slots such as rectangular and triangular aperture coupling slots are studied and compared. It is found that the antenna with triangular aperture coupling slot enhances the antenna performance by suppressing 2nd and 3rd harmonics at 5 GHz and 8 GHz, respectively, increasing the antenna gain and providing a better circular polarization behavior. The simulated antenna design achieves a gain of 9 dB, return loss of -23.6 dB, axial ratio of 1.27 dB and axial-ratio bandwidth of 40.8 % (2~3 GHz). The proposed antenna shows an enhancement in the antenna performance which makes it a suitable candidate for rectifying antenna or rectenna application as it can increase the total conversion efficiency resulting in a high output DC voltage used to power low power electronic and electrical devices such as wireless sensor. [ABSTRACT FROM AUTHOR]

A Chunk by chunk-based allocation is an emerging subcarrier allocation in Single Carrier Frequency Division Multiple Access (SC-FDMA) due to its low complexity. In this paper, a combined userorder and chunk-order allocation for solving chunk allocation problem which minimizes the average BER of all users while improving the throughput in SC-FDMA uplink is proposed. The subcarrier grouping into a chunk of all users on both-order allocations are performed by averaging the BER of a contiguous subcarriers within a chunk. The sequence of allocation is according to the average of users' BER on userorder allocation and the average of chunks' BER on chunk-order allocation. The best allocation is determined by choosing one of both-order allocations which provides the smaller BER systems. The simulation results showed that the proposed algorithm can outperform the previous algorithms in term of average BER and throughput without increase the time complexity. [ABSTRACT FROM AUTHOR]

This paper presents the computational of two-way fluid structure interaction technique by using Mesh based Parallel Code Coupling Interface for the visualization of wiresweep in the electronics packaging. Polymer rheology models with Castro-Macosko model have been used in the fluid flow model and Volume of Fluid technique was applied to melt front tracking of the fluid. The numerical analysis used User-Defined Function to allow curing kinetic model. Wiresweep profiles and pressure distribution within the mold are presented. The numerical results of melt front patterns and filled volume were compared with the previous experimental results and found in good agreement. [ABSTRACT FROM AUTHOR]

A finite element model of the expansion Joints' common damages of a novel comb-plate by using the finite element software ABAQUS is presented in this paper. The mechanical behavior of expansion Joints is analyzed to verify the weak parts of it. The research results provide a reference for the design of the comb-plate expansion Joints. [ABSTRACT FROM AUTHOR]

This paper presented stability application for chaos synchronization using a 6-D hyperchaotic system of different controllers and two tools: Lyapunov stability theory and Linearization methods. Synchronization methods based on nonlinear control strategy is used. The selecting controller's methods have been modified by applying complete synchronization. The Linearization methods can achieve convergence according to the of complete synchronization. Numerical simulations are carried out by using MATLAB to validate the effectiveness of the analytical technique [ABSTRACT FROM AUTHOR]