Search results for: sensitive transmission lines.

Authors: Jyoti Narayan, S. Choudhary

Abstract:

Nanowire arrays of copper with uniform diameters have been synthesized by potentiostatic electrochemical metal deposition (EMD) of copper sulphate and potassium chloride solution within the nano-channels of porous Indium-Tin Oxide (ITO), also known as Tin doped Indium Oxide templates. The nanowires developed were fairly continuous with diameters ranging from 110-140 nm along the entire length. Single as well as poly-crystalline copper wires have been prepared by application of appropriate potential during the EMD process. Scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), small angle electron diffraction (SAED) and atomic force microscopy (AFM) were used to characterize the synthesized nano wires at room temperature. The electrochemical response of synthesized products was evaluated by cyclic voltammetry while surface energy analysis was carried out using a Goniometer.

Keywords: Electro-deposition, Metallic nano-wires, Nanomaterials, Template synthesis

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Authors: Nikhil Jain, Yang Xu, Bin Yu

Abstract:

The material behavior of graphene, a single layer of carbon lattice, is extremely sensitive to its dielectric environment. We demonstrate improvement in electronic performance of graphene nanowire interconnects with full encapsulation by lattice-matching, chemically inert, 2D layered insulator hexagonal boron nitride (h- BN). A novel layer-based transfer technique is developed to construct the h-BN/MLG/h-BN heterostructures. The encapsulated graphene wires are characterized and compared with that on SiO2 or h-BN substrate without passivating h-BN layer. Significant improvements in maximum current-carrying density, breakdown threshold, and power density in encapsulated graphene wires are observed. These critical improvements are achieved without compromising the carrier transport characteristics in graphene. Furthermore, graphene wires exhibit electrical behavior less insensitive to ambient conditions, as compared with the non-passivated ones. Overall, h-BN/graphene/h- BN heterostructure presents a robust material platform towards the implementation of high-speed carbon-based interconnects.

Keywords: Two-dimensional nanosheet, graphene, hexagonal boron nitride, heterostructure, interconnects.

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Authors: Young-Il Kim, Bong-Jae Yi, Jae-Ju Song, Jin-Ho Shin, Jung-Il Lee

Abstract:

Firstly, research and development on RFID focuses on manufacturing and retail sectors, because it can improve supply chain efficiency. But, now a variety of field is considered the next research area for Radio Frequency Identification (RFID). Although RFID is infancy, RFID technology has great potential in power industry to significantly reduce cost, and improve quality of power supply. To complement the limitation of RFID, we adopt the WSN (Wireless Sensor Network) technology. However, relevant experience is limited, the challenge will be to derive requirement from business practice and to determine whether it is possible or not. To explore this issue, we conduct a case study on implementing power facility management system using RFID/WSN in Korea Electric Power Corporation (KEPCO). In this paper we describe requirement from power industry. And we introduce design and implementation of the test bed.

Keywords: Power Facility Management, RFID/WSN, Transmission Tower, Underground Tunnel, ZigBee.

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Authors: A. T. Kamzanova, G. Matthews, A. M. Kustubayeva, S. M. Jakupov

Abstract:

The aim of this study was to evaluate the sensitivity of a range of EEG indices to time-on-task effects and to a workload manipulation (cueing), during performance of a resource-limited vigilance task. Effects of task period and cueing on performance and subjective state response were consistent with previous vigilance studies and with resource theory. Two EEG indices – the Task Load Index (TLI) and global lower frequency (LF) alpha power – showed effects of task period and cueing similar to those seen with correct detections. Across four successive task periods, the TLI declined and LF alpha power increased. Cueing increased TLI and decreased LF alpha. Other indices – the Engagement Index (EI), frontal theta and upper frequency (UF) alpha failed to show these effects. However, EI and frontal theta were sensitive to interactive effects of task period and cueing, which may correspond to a stronger anxiety response to the uncued task.

Keywords: brain activity, EEG, task engagement, vigilance task.

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Authors: Abdel-Aziz M. Mohamed, Nermeen Coutry

Abstract:

Lead time is a critical measure of a supply chain's performance. It impacts both the customer satisfactions as well as the total cost of inventory. This paper presents the result of a study on the analysis of the customer order lead-time for a multinational company. In the study, the lead time was divided into three stages respectively: order entry, order fulfillment, and order delivery. A sample of size 2,425 order lines was extracted from the company's records to use for this study. The sample data entails information regarding customer orders from the time of order entry until order delivery. Data regarding the lead time of each stage for different orders were also provided. Summary statistics on lead time data reveals that about 30% of the orders were delivered later than the scheduled due date. The result of the multiple linear regression analysis technique revealed that component type, logistics parameter, order size and the customer type have significant impacts on lead time. Data analysis on the stages of lead time indicates that stage 2 consumed over 50% of the lead time. Pareto analysis was made to study the reasons for the customer order delay in each stage. Recommendation was given to resolve the problem.

Keywords: Lead time reduction, customer satisfaction, service quality, statistical analysis.

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Authors: Marko Mailand, Hans-Joachim Jentschel

Abstract:

For today-s and future wireless communications applications, more and more data traffic has to be transmitted with growing speed and quality demands. The analog front-end of any mobile device has to cope with very hard specifications regardless which transmission standard has to be supported. State-of-the-art analog front-end implementations are reaching the limit of technical feasibility. For that reason, alternative front-end architectures could support a continuing development of mobile communications e.g., six-port-based front-ends [1], [2]. In this article we propose an analog front-end with high intermediate frequency and which utilizes additive mixing instead of multiplicative mixing. The system architecture is presented and several spurious effects as well as their influence on the system dimensioning are discussed. Furthermore, several issues concerning the technical feasibility are provided and some simulation results are discussed which show the principle functionality of the proposed superposition heterodyne receiver.

Keywords: receivers, analog front-end, heterodyning, self-mixing.

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Authors: L. Labéjof, I. Mororó, P. Galle, G. Barbosa, M.I. Severo, A.H. de Oliveira

Abstract:

Ultrastructure of duodenum mucosa of irradiated rat was studied versus dose rate of irradiation following exposure to gamma rays from 60-Cobalt source. The animals were whole body irradiated at two dose rates (1 Gy.mn-1 and 1 Gy.h-1) and three total doses (1, 2 or 4 Gy) for each dose rate. 24 or 48 h after irradiation, their small intestine was removed and samples of duodenum were processed for observations under a transmission electron microscopy. Samples of duodenum mucosa of control rats were processed in the same way. For the lower dose rate of 1 Gy.h-1, main lesions characteristic of apoptosis were detected within irradiated enterocytes at a total dose of 2 Gy and 24 h after exposure. Necrosis was noted in the samples, 48 h after exposition. For the higher dose rate of 1 Gy.mn-1, fewer changes were detected at all total doses 24 or 48 h irradiation. Thus, it was shown that the appearance of radiationinduced alterations varies not only with increasing total dose and post-irradiation time but especially with decreasing dose rate.

Keywords: Dose rate, Radiation Inury, Apoptosis, SmallBowel

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Authors: Manikanta Prasad Banda, Che Hua Yang

Abstract:

Anti-symmetric wave propagation along the particle motion of the wedge waves is known as anti-symmetric flexural (ASF) modes which travel along the wedge tips of the mid-plane apex with a small truncation. This paper investigates the characteristics of the ASF modes propagation with the wedge tip crack. The simulation and experimental results obtained by a three-dimensional (3-D) finite element model explained the contact acoustic non-linear (CAN) behavior in explicit dynamics in ABAQUS and the ultrasonic non-destructive testing (NDT) method is used for defect detection. The effect of various parameters on its high and low-level conversion modes are known for complex reflections and transmissions involved with direct reflections and transmissions. The results are used to predict the location of crack through complex transmission and reflection coefficients.

Keywords: ASF mode, crack detection, finite elements method, laser ultrasound technique, wedge waves.

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Authors: Chuen-Ching Wang, Yao-Tang Chang, Yu-Chang Hsu

Abstract:

A simple but effective digital watermarking scheme utilizing a context adaptive variable length coding (CAVLC) method is presented for wireless communication system. In the proposed approach, the watermark bits are embedded in the final non-zero quantized coefficient of each DCT block, thereby yielding a potential reduction in the length of the coded block. As a result, the watermarking scheme not only provides the means to check the authenticity and integrity of the video stream, but also improves the compression ratio and therefore reduces both the transmission time and the storage space requirements of the coded video sequence. The results confirm that the proposed scheme enables the detection of malicious tampering attacks and reduces the size of the coded H.264 file. Therefore, the current study is feasible to apply in the video applications of wireless communication such as 3G system

Keywords: 3G, wireless communication, CAVLC, digitalwatermarking, motion compensation

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Authors: Y. Mohseniahouei, K. Abdella, M. Pollanen

Abstract:

In this paper, we explore the applicability of the Sinc- Collocation method to a three-dimensional (3D) oceanography model. The model describes a wind-driven current with depth-dependent eddy viscosity in the complex-velocity system. In general, the Sinc-based methods excel over other traditional numerical methods due to their exponentially decaying errors, rapid convergence and handling problems in the presence of singularities in end-points. Together with these advantages, the Sinc-Collocation approach that we utilize exploits first derivative interpolation, whose integration is much less sensitive to numerical errors. We bring up several model problems to prove the accuracy, stability, and computational efficiency of the method. The approximate solutions determined by the Sinc-Collocation technique are compared to exact solutions and those obtained by the Sinc-Galerkin approach in earlier studies. Our findings indicate that the Sinc-Collocation method outperforms other Sinc-based methods in past studies.

Keywords: Boundary Value Problems, Differential Equations, Sinc Numerical Methods, Wind-Driven Currents

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Authors: A. Hayati Soloot, A. Gholami, E. Agheb, A. Ghorbandaeipour, P. Mokhtari

Abstract:

The two significant overvoltages in power system, switching overvoltage and lightning overvoltage, are investigated in this paper. Firstly, the effect of various power system parameters on Line Energization overvoltages is evaluated by simulation in ATP. The dominant parameters include line parameters; short-circuit impedance and circuit breaker parameters. Solutions to reduce switching overvoltages are reviewed and controlled closing using switchsync controllers is proposed as proper method. This paper also investigates lightning overvoltages in the overhead-cable transition. Simulations are performed in PSCAD/EMTDC. Surge arresters are applied in both ends of cable to fulfill the insulation coordination. The maximum amplitude of overvoltages inside the cable is surveyed which should be of great concerns in insulation coordination studies.

Keywords: Switching Overvoltage, Lightning Overvoltage, Insulation Coordination, ATP, PSCAD/EMTDC.

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Authors: P. Mohamed Fathimal, P. Arockia Jansi Rani

Abstract:

In this era of online communication, which transacts data in 0s and 1s, confidentiality is a priced commodity. Ensuring safe transmission of encrypted data and their uncorrupted recovery is a matter of prime concern. Among the several techniques for secure sharing of images, this paper proposes a k out of n region incrementing image sharing scheme for color images. The highlight of this scheme is the use of simple Boolean and arithmetic operations for generating shares and the Lagrange interpolation polynomial for authenticating shares. Additionally, this scheme addresses problems faced by existing algorithms such as color reversal and pixel expansion. This paper regenerates the original secret image whereas the existing systems regenerates only the half toned secret image.

Keywords: Threshold Secret Sharing Scheme, Access Control, Steganography, Authentication, Secret Image Sharing, XOR, Pixel Expansion.

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Authors: F. Esmaeilzadeh, M. E. Zeighami, J. Fathi

Abstract:

This paper describes a one-dimensional numerical model for natural gas production from the dissociation of methane hydrate in hydrate-capped gas reservoir under depressurization and thermal stimulation. Some of the hydrate reservoirs discovered are overlying a free-gas layer, known as hydrate-capped gas reservoirs. These reservoirs are thought to be easiest and probably the first type of hydrate reservoirs to be produced. The mathematical equations that can be described this type of reservoir include mass balance, heat balance and kinetics of hydrate decomposition. These non-linear partial differential equations are solved using finite-difference fully implicit scheme. In the model, the effect of convection and conduction heat transfer, variation change of formation porosity, the effect of using different equations of state such as PR and ER and steam or hot water injection are considered. In addition distributions of pressure, temperature, saturation of gas, hydrate and water in the reservoir are evaluated. It is shown that the gas production rate is a sensitive function of well pressure.

Keywords: Hydrate reservoir, numerical modeling, depressurization, thermal stimulation, gas generation.

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Authors: Jae Keun Park, Sung Je Hong, Kyong Hoon Kim, Tae Heum Kang, Wan Yeon Lee

Abstract:

In this paper, we propose a routing scheme that guarantees the residual lifetime of wireless sensor networks where each sensor node operates with a limited budget of battery energy. The scheme maximizes the communications QoS while sustaining the residual battery lifetime of the network for a specified duration. Communication paths of wireless nodes are translated into a directed acyclic graph(DAG) and the maximum-flow algorithm is applied to the graph. The found maximum flow are assigned to sender nodes, so as to maximize their communication QoS. Based on assigned flows, the scheme determines the routing path and the transmission rate of data packet so that any sensor node on the path would not exhaust its battery energy before a specified duration.

Keywords: Sensor network, battery, residual lifetime, routingscheme, QoS

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Authors: Deepti Tamrakar, Pritee Khanna

Abstract:

This manuscript presents, palmprint recognition by combining different texture extraction approaches with high accuracy. The Region of Interest (ROI) is decomposed into different frequencytime sub-bands by wavelet transform up-to two levels and only the approximate image of two levels is selected, which is known as Approximate Image ROI (AIROI). This AIROI has information of principal lines of the palm. The Competitive Index is used as the features of the palmprint, in which six Gabor filters of different orientations convolve with the palmprint image to extract the orientation information from the image. The winner-take-all strategy is used to select dominant orientation for each pixel, which is known as Competitive Index. Further, PCA is applied to select highly uncorrelated Competitive Index features, to reduce the dimensions of the feature vector, and to project the features on Eigen space. The similarity of two palmprints is measured by the Euclidean distance metrics. The algorithm is tested on Hong Kong PolyU palmprint database. Different AIROI of different wavelet filter families are also tested with the Competitive Index and PCA. AIROI of db7 wavelet filter achievs Equal Error Rate (EER) of 0.0152% and Genuine Acceptance Rate (GAR) of 99.67% on the palm database of Hong Kong PolyU.

Keywords: DWT, EER, Euclidean Distance, Gabor filter, PCA, ROI.

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Authors: B. Lonla Moffo, J. Mbihi, L. Nneme Nneme

Abstract:

In this paper, a low cost duty-cycle modulation scheme is studied in depth and compared to the standard pulse width modulation technique. Using a mix of analytical reasoning and electronics simulation tools, it is shown that under the same operating conditions, most characteristics of the proposed duty-cycle modulation scheme are better than those provided by a standard pulse width modulation technique. The simulation results obtained when testing both modulation control policies on prototyping systems, indicate that the proposed duty-cycle modulation approach, appears to be a high quality control policy in a wide variety of application areas, including A/D and D/A conversion, signal transmission and switching control in power electronics.

Keywords: Duty-cycle Modulation, Operational amplifiers, Pulse width modulation, Power electronics, Signal processing.

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Authors: N. Miklavčič, U. Kugovnik, N. Galkina, P. Ribarič, R. Vončina

Abstract:

Today the need for weather predictions is deeply rooted in the everyday life of people as well as it is in industry. The forecasts influence final decision-making processes in multiple areas from agriculture and prevention of natural disasters to air traffic regulations and solutions on a national level for health, security, and economic problems. Namely in Slovenia, alongside other existing forms of application, weather forecasts are adopted for the prognosis of electrical current transmission through powerlines. Meteorological parameters are one of the key factors which need to be considered in estimations of the reliable supply of electrical energy to consumers. And like for any other measured value, the knowledge about measurement uncertainty is critical also for the secure and reliable supply of energy. The estimation of measurement uncertainty grants us a more accurate interpretation of data, a better quality of the end results, and even a possibility of improvement of weather forecast models.

Keywords: Measurement uncertainty, microscale meteorological model, CALMET meteorological station, orthogonal regression.

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Authors: Fuh-Hsin Hwang, Tsui-Tsai Lin, Chih-Wen Chan, Cheng-Yuan Chang

Abstract:

This paper studies the design of a simple constellation precoding for a multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) system over Rayleigh fading channels where OFDM is used to keep the diversity replicas orthogonal and reduce ISI effects. A multi-user environment with K synchronous co-channel users is considered. The proposed scheme provides a bandwidth efficient transmission for individual users by increasing the system throughput. In comparison with the existing coded MIMO-OFDM schemes, the precoding technique is designed under the consideration of its low implementation complexity while providing a comparable error performance to the existing schemes. Analytic and simulation results have been presented to show the distinguished error performance.

Keywords: coded modulation, diversity technique, OFDM, MIMO, constellation precoding

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Authors: I. A. Farhat

Abstract:

The The dynamic economic dispatch (DED) problem is one of the complex constrained optimization problems that have nonlinear, con-convex and non-smooth objective functions. The purpose of the DED is to determine the optimal economic operation of the committed units while meeting the load demand. Associated to this constrained problem there exist highly nonlinear and non-convex practical constraints to be satisfied. Therefore, classical and derivative-based methods are likely not to converge to an optimal or near optimal solution to such a dynamic and large-scale problem. In this paper, an Artificial Immune System technique (AIS) is implemented and applied to solve the DED problem considering the transmission power losses and the valve-point effects in addition to the other operational constraints. To demonstrate the effectiveness of the proposed technique, two case studies are considered. The results obtained using the AIS are compared to those obtained by other methods reported in the literature and found better.

Keywords: Artificial Immune System (AIS), Dynamic Economic Dispatch (DED).

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Authors: C. Photiphitak, P. Rakkwamsuk, P. Muthitamongkol, C. Sae-Kung, C. Thanachayanont

Abstract:

TiO2/Ag composite films were prepared by incorporating Ag in the pores of mesoporous TiO2 films using a photoreduction method. The Ag nanoparticle sizes were in a range of 3.66-38.56 nm. The TiO2/Ag composite films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscropy (TEM). The TiO2 films and TiO2/Ag composite films were immersed in a 0.3 mM N719 dye solution and characterized by UV-Vis spectrophotometer. The TiO2/Ag/N719 composite film showed that an optimal size of Ag nanoparticles was 19.12 nm and, hence, gave the maximum optical absorption spectra. The improved absorption was due to surface plasmon resonance induced by the Ag nanoparticles to enhance the absorption coefficient of the dye.

Keywords: Silver nanoparticle, TiO2/Ag composite films, Optical properties, surface plasmon resonance

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Authors: Hojat Heidari-Bafroui, Amer Charbaji, Constantine Anagnostopoulos, Mohammad Faghri

Abstract:

Phosphorus is an essential nutrient for plant life which is most frequently found as phosphate in water. Once phosphate is found in abundance in surface water, a series of adverse effects on an ecosystem can be initiated. Therefore, a portable and reliable method is needed to monitor the phosphate concentrations in the field. In this paper, an inexpensive dip strip device with the ascorbic acid/antimony reagent dried on blotting paper along with wet chemistry is developed for the detection of low concentrations of phosphate in water. Ammonium molybdate and sulfuric acid are separately stored in liquid form so as to improve significantly the lifetime of the device and enhance the reproducibility of the device’s performance. The limit of detection and quantification for the optimized device are 0.134 ppm and 0.472 ppm for phosphate in water, respectively. The device’s shelf life, storage conditions, and limit of detection are superior to what has been previously reported for the paper-based phosphate detection devices.

Keywords: Phosphate detection, paper-based device, molybdenum blue method, colorimetric assay.

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Authors: M. Padmavathi, R. M. Suresh

Abstract:

Every machine plays roles of client and server simultaneously in a peer-to-peer (P2P) network. Though a P2P network has many advantages over traditional client-server models regarding efficiency and fault-tolerance, it also faces additional security threats. Users/IT administrators should be aware of risks from malicious code propagation, downloaded content legality, and P2P software’s vulnerabilities. Security and preventative measures are a must to protect networks from potential sensitive information leakage and security breaches. Bit Torrent is a popular and scalable P2P file distribution mechanism which successfully distributes large files quickly and efficiently without problems for origin server. Bit Torrent achieved excellent upload utilization according to measurement studies, but it also raised many questions as regards utilization in settings, than those measuring, fairness, and Bit Torrent’s mechanisms choice. This work proposed a block selection technique using Fuzzy ACO with optimal rules selected using ACO.

Keywords: Ant Colony Optimization (ACO), Bit Torrent, Download time, Peer-to-Peer (P2P) network, Performance.

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Authors: Shigenori Togashi, Mitsuhiro Matsuzawa

Abstract:

A pilot plant for continuous flow microwave-assisted chemical reaction combined with microreactors was developed and water heating tests were conducted for evaluation of the developed plant. We developed a microwave apparatus having a single microwave generator that can heat reaction solutions in four reaction fields simultaneously in order to increase throughput. We also designed a four-branch waveguide using electromagnetic simulation, and found that the transmission efficiency at 99%. Finally, we developed the pilot plant using the developed microwave apparatus and conducted water heating tests. The temperatures in the respective reaction fields were controlled within ±1.1 K at 353.2 K. Moreover, the energy absorption rates by the water were about 90% in the respective reaction fields, whereas the energy absorption rate was about 40% when 100 cm3 of water was heated by a commercially available multimode microwave chemical reactor.

Keywords: Microwave, Microreactor, Heating, Electromagnetic Simulation

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Authors: J.E. Park, G.R. Kim, D.J. Yoon, C.H. Sin, I.S. Park, T.S. Bea, M.H. Lee

Abstract:

Carbon nanotubes (CNTs) are attractive because of their excellent chemical durability mechanical strength and electrical properties. Therefore there is interest in CNTs for not only electrical and mechanical application, but also biological and medical application. In this study, the dispersion power of surfactant-treated multiwalled carbon nanotubes (MWCNTs) and their effect on the antibacterial activity were examined. Surfactant was used sodium dodecyl-benzenesulfonate (SDBS). UV-vis absorbance and transmission electron microscopy(TEM) were used to characterize the dispersion of MWCNTs in the aqueous phase, showing that the surfactant molecules had been adsorbed onto the MWCNTs surface. The surfactant-treated MWCNTs exhibited antimicrobial activities to streptococcus mutans. The optical density growth curves and viable cell number determined by the plating method suggested that the antimicrobial activity of surfactant-treated MWCNTs was both concentration and treatment time-dependent.

Keywords: MWCNT, SDBS, surfactant, antibacterial.

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Authors: Won-Ho Kim, Chang-Ho Hyun, Moon-Jung Kim

Abstract:

In this paper, zigbee communication based wireless energy surveillance system is presented. The proposed system consists of multiple energy surveillance devices and an energy surveillance monitor. Each different standby power-off value of electric device is set automatically by using learning function of energy surveillance device. Thus adaptive standby power-off function provides user convenience and it maximizes the energy savings. Also, power consumption monitoring function is helpful to reduce inefficient energy consumption in home. The zigbee throughput simulator is designed to evaluate minimum transmission power and maximum allowable information quantity in the proposed system. The test result of prototype has been satisfied all the requirements. The proposed system has confirmed that can be used as an intelligent energy surveillance system for energy savings in home or office.

Keywords: Energy monitoring system, Energy surveillance system, Energy sensor network, Energy savings.

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Authors: Vijay Gajanan Neve, Pallavi V. Pullawar, G. M. Dhole

Abstract:

Modern industrial processes are based on a large amount of electronic devices such as programmable logic controllers and adjustable speed drives. Unfortunately, electronic devices are sensitive to disturbances, and thus, industrial loads become less tolerant to power quality problems such as sags, swells, and harmonics. Voltage sags are an important power quality problem. In this paper proposed a new configuration of Static Var Compensator (SVC) considering three different conditions named as topologies and Booster transformer with fuzzy logic based controller, capable of compensating for power quality problems associated with voltage sags and maintaining a prescribed level of voltage profile. Fuzzy logic controller is designed to achieve the firing angles for SVC such that it maintains voltage profile. The online monitoring system for voltage sag mitigation in the laboratory using the hardware is used. The results are presented from the performance of each topology and Booster transformer considered in this paper.

Keywords: Booster Transformer, Fuzzy logic, Static Var Compensator, Voltage sag.

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Authors: Siti Mutmainah, Slamet Sugiri

Abstract:

Organizations are increasingly relying upon teamwork; however, little is known about the best fit among incentive system, team composition, and group performance. To further explore this issue this study examines whether the congruence between incentive system and locus of control (LoC) affects team performance. To reconcile opposite lines of argument in literature regarding the best incentive system for a team, this paper uses the social identity perspective and person-environment (P-E) fit theory to understand behavior in a group process. A laboratory experiment with postgraduate students is conducted to test the hypotheses. One hundred and five accounting students were assigned to three-person work groups, where they completed an independent task under one of two types of incentive—individual and group incentive systems—after their LoC was measured. The findings confirm the hypothesis. Group incentive results in an enhanced team performance. Team performance is better when there is congruence between incentive system and LoC. Group incentive system combined with external LoC results in the best performance, while individual incentive system results in a better team performance when combined with internal LoC. The result suggests that a cooperative process enables ‘ordinary people’ to obtain extraordinary results.

Keywords: Incentive system, locus of control, person-environment fit, social identity perspective, team performance.

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Authors: Mohd Iqbal Ridwan, Kerk Lee Yen, Aminuddin Musa, Bahisham Yunus

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Protective relays are components of a protection system in a power system domain that provides decision making element for correct protection and fault clearing operations. Failure of the protection devices may reduce the integrity and reliability of the power system protection that will impact the overall performance of the power system. Hence it is imperative for power utilities to assess the reliability of protective relays to assure it will perform its intended function without failure. This paper will discuss the application of reliability analysis using statistical method called Life Data Analysis in Tenaga Nasional Berhad (TNB), a government linked power utility company in Malaysia, namely Transmission Division, to assess and evaluate the reliability of numerical overcurrent protective relays from two different manufacturers.

Keywords: Life data analysis, Protective relays, Reliability, Weibull Distribution.

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Authors: Rani Astya, S.C. Sharma

Abstract:

The wireless adhoc network is comprised of wireless node which can move freely and are connected among themselves without central infrastructure. Due to the limited transmission range of wireless interfaces, in most cases communication has to be relayed over intermediate nodes. Thus, in such multihop network each node (also called router) is independent, self-reliant and capable to route the messages over the dynamic network topology. Various protocols are reported in this field and it is very difficult to decide the best one. A key issue in deciding which type of routing protocol is best for adhoc networks is the communication overhead incurred by the protocol. In this paper STAR a table driven and DSR on demand protocols based on IEEE 802.11 are analyzed for their performance on different performance measuring metrics versus varying traffic CBR load using QualNet 5.0.2 network simulator.

Keywords: Adhoc networks, wireless networks, CBR, routingprotocols, route discovery, simulation, performance evaluation, MAC, IEEE 802.11, STAR, DSR

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Authors: Hilal A. Fadhil, Syed A. Aljunid, R. Badlishah Ahmed

Abstract:

In this paper we study the use of a new code called Random Diagonal (RD) code for Spectral Amplitude Coding (SAC) optical Code Division Multiple Access (CDMA) networks, using Fiber Bragg-Grating (FBG), FBG consists of a fiber segment whose index of reflection varies periodically along its length. RD code is constructed using code level and data level, one of the important properties of this code is that the cross correlation at data level is always zero, which means that Phase intensity Induced Phase (PIIN) is reduced. We find that the performance of the RD code will be better than Modified Frequency Hopping (MFH) and Hadamard code It has been observed through experimental and theoretical simulation that BER for RD code perform significantly better than other codes. Proof –of-principle simulations of encoding with 3 channels, and 10 Gbps data transmission have been successfully demonstrated together with FBG decoding scheme for canceling the code level from SAC-signal.

Keywords: FBG, MFH, OCDMA, PIIN, BER.

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