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Optimal Voltage Stability Improvement under Contingencies using Flower Pollination Algorithm and Thyristor Controlled Series Capacitor
No full textRecent power systems necessitate for maintaining a safe voltage stability as the number of problems such as contingencies and reactive power insufficiency are increasing. In this paper, installation and sizing of Flexible Alternating Current Transmission System (FACTS) devices have been introduced for solving the voltage stability problems under contingencies. The FACTS device to be used is Thyristor Controlled Series Capacitor (TCSC). Besides improving the voltage magnitude at all buses to a desired level, installation of TCSC at proper locations can minimize total transmission losses of the system. To conduct the sizing task, the newly developed Flower Pollination Algorithm (FPA) has been implemented as the engine for optimization. Through experimentation, the results proved that the proposed placement and sizing technique has successfully mitigated the voltage stability problems. In addition, the computation time for FPA’s convergence was tolerable with optimum results
Review on Public Key Cryptography Scheme-Based Performance Metrics
No full textCryptography is a method used to establish secure data communication. The goal of cryptography is to send data to satisfy the criteria of confidentiality, data integrity, authentication and non-repudiation. In line with the goals, the performance metrics is the important evaluation criteria to be analyzed. This paper presents the review of performance metrics of Public Key Cryptography (PKC) that had been analyzed based on the PKC scheme from the previous researchers’ effort since the last four decades. It also displayed the research pattern in different performance metrics over the years. The aim of this paper is to identify the key performance metrics which addressed by the researchers in previous studies. Finally, the critical concern of this paper which shows the overall PKC performance metrics also presented in this paper
Link Adaptation Algorithm for IEEE 802.11 Wireless Local Area Netwoks in Fading Channel
No full textThis paper proposes an enhance version of the dual parameter based cost function algorithm for time-varying environments. For ideal channel condition, the proposed cost function algorithm adaptively change the transmission data rate according to traffic load condition. However, similar approach is not well-suited for time-varying environment. For time-varying condition, transmission of packet at lower transmission data rate is much preferred in order to achieve reliable transmission. In addition to that, packet transmission at lower data rate contributes to low energy consumption due to lower transmit power used to transmit packet. This paper presents a combination of cost function algorithm with adaptive rate/power. Adaptation of transmission data rate and transmit power for time varying condition are carried out based on received power values. An OPNET based simulation model was developed to analyses the performance of the propose algorithm. Simulation results show the proposed algorithm can significantly improve the energy efficiency of a WLAN while maintaining the network QoS in fading channel environments
Implementation of Stereo Vision Semi-Global Block Matching Methods for Distance Measurement
No full textStereo vision has become an attractive topic research in the last decades. Many implementations such as the autonomous car, 3D movie, 3D object generation, are produced using this technique. The advantages of using two cameras in stereo vision are the disparity map between images. Disparity map will produce distance estimation of the object. Distance measurement is a crucial parameter for an autonomous car. The distance between corresponding points between the left and right images must be precisely measured to get an accurate distance. One of the most challenging in stereo vision is to find corresponding points between left and right images (stereo matching). This paper proposed distance measurement using stereo vision using Semi-Global Block Matching algorithm for stereo matching purpose. The object is captured using a calibrated stereo camera. The images pair then optimized using WLS Filter to reduce noises. The implementation results of this algorithm are furthermore converted to a metric unit for distance measurement. The result shows that the stereo vision distance measurement using Semi-Global Block Matching gives a good result. The obtained best result of this work contains error of less than 1% for 1m distanc
Triangular Microstrip Antenna for Circularly-Polarized Synthetic Aperture Radar Sensor Application
No full textIn this paper, we obtain the basic construction of triangular microstrip antennas based on the analysis of the single patch and array two patches. This construction use the basic corporate feeding-line with modified lossless T-junction power divider for Circularly Polarized-Synthetic Aperture Radar (CP-SAR) sensor embedded on airspace with compact, small, and simple configuration. The design of Circular Polarization (CP) is realized by truncating the whole three tips and adjusted the parameters of antennas at the resonant frequency, f = 1.25 GHz. The equations for reciprocal, lossless, and matched of the modified lossless T-junction power divider are also described. The result of characteristic performance and S-parameter for the single patch both Left-Hand Circular Polarization (LHCP) and Right-Hand Circular Polarization (RHCP) at the resonant frequency show consecutively 7.15 dBic and 7.16 dBic of gain, 0.12 dB and 0.11 dB of axial ratio, -26.75 dB and -26.72 dB of S-parameter. For array two patches, the result of gain, axial ratio, and S-parameter both of LHCP and RHCP are 7.63 dBic, 7.62 dBic, 2.68 dB, 2.74 dB, -19.43 dB, and -19.40 dB, respectively. The modified lossless T-junction power divider both for LHCP and RHCP are capable of being reciprocal, matched, and lossless at all ports
A Modified Boltzmann Machine for Solving Distribution System Expansion Planning in Malaysia
No full textThis paper proposes an effective technique to solve Distribution System Expansion Planning (DSEP) problem by using the artificial neural network. The proposed technique will be formulated by using mean-variance analysis (MVA) approach in the form of mixed-integer quadratic programming problem. It consists of two layers neural network which combine Hopfield network and Boltzmann machine (BM) in upper and lower layer respectively named as Modified BM. The originality of the proposed technique is it will delete the unit of the second layer, which is not selected in the first layer in its execution. Then, the second layer is restructured using the selected units. Due to this feature, the proposed technique will improve time consuming and accuracy of solution. Referring to the case study demonstrated in this paper, the significance outputs obtained are the improvement in computational time and accuracy of solution provided. As the solution provided various of options, the proposed technique will help decision makers in solving DSEP problem. As a result, the performance of strategic investment planning in DSEP certainly enhanced
Robust Visual Multi Target Trackers: A Review
No full textIn this review paper, we address on the state-of-art process with visual object tracking in video surveillance, medical and military applications. In the present scenario number of algorithms and methods are used to track the object in the different scene, a robust visual object tracking remains a critical challenge. The challenges arise due to object motion from frame to frame with a change in appearance, structures, illumination, and occlusion. In this paper, at last, we outline the different algorithms, dataset, strength, and weakness of the different object tracker
Web server-based distributed machine socialization system
No full textIn recent years, there has been an increasing trend of offering services that are useful to users, such as Google's Nest, through machine socialization between parts and devices in specific spaces such as automobiles, homes, and factories. The existing inter - device collaboration system is a centralized system using router, and it controls collaboration between devices by building OpenWrt and web server on router. However, due to the limited hardware resources on the router, it generates network traffic congestion as the number of requests from the client increases or the number of clients connected to the server increases. In this paper, we propose a distributed machine collaboration system based on web server using inter - device collaboration algorithm. The study of Micro Controller Unit (MCU) has reduced the traffic incidence by solving the request sent to the router from each device by oneself
Joint Routing and Congestion Control in Multipath Channel Based on Signal to Noise Ratio with Cross Layer Scheme
No full textRouting protocol and congestion control in Transmission Control Protocol (TCP) have important roles in wireless mobile network performance. In wireless communication, the stability of the path and successful data transmission will be influenced by the channel condition. This channel condition constraints come from path loss and the multipath channel fading. With these constraints, the algorithm in the routing protocol and congestion control is confronted with the uncertainty of connection quality and probability of successful packet transmission, respectively. It is important to investigate the reliability and robustness of routing protocol and congestion control algorithms in dealing with such situation. In this paper, we develop a detailed approach and analytical throughput performance with a cross layer scheme (CLS) between routing and congestion control mechanism based on signal to noise ratio (SNR) in Rician and Rayleigh as multipath fading channel. We proposed joint routing and congestion control TCP with a cross layer scheme model based on SNR (RTCP-SNR). We compare the performance of RTCP-SNR with conventional routing-TCP and routing-TCP that used CLS with routing aware (RTCP-RA) model. The analyses and the simulation results showed that RTCP-SNR in a multipath channel outperforms conventional routing-TCP and RTCP-RA
Experimental Validation of Shared Inverter Topology to Drive Multi AC-Loads
No full textMany reduced-switch-count (RSC) inverter topologies have been proposed in the literature. As the number of switches required to produce a set of voltages in RSC inverters are less than that in conventional inverter, as a result utilizing RSC inverters in a certain system reduces its size and cost. In this paper, a novel RSC shared inverter topology consisting of fifteen switches and capable of driving four three-phase AC-loads independently is proposed and experimentally verified. A carrier-based pulse width modulation (PWM) technique that employs the zero-sequence-signal injection principle is developed to drive the the proposed inverter along with adequate DC voltage bus utilization between the shared loads for common frequency (CF) as well as different frequency (DF) modes. The structure and the principle of operation of the proposed inverter are introduced and intensively verified using simulation and field-programmable-gate-array (FPGA)-in-the-loop simulation under linear and nonlinear loads. Then, Inverter prototype was built and the proposed inverter has been verified experimentally. The experimental results verify the applicability of the proposed inverter and the employed PWM