This is the idea of using existing power lines for communication purposes. Powerlinecommunications (PLC) enables network communication of voice, data, and video over direct power lines. High-speed PLC involves data rates in excess of 10 Mbps. PLC has attracted a lot of attention and has become an interesting subject of research lately.
This paper bring out a 32X32 bit reversible Vedic multiplier using "Urdhva Tiryakabhayam" sutra meaning vertical and crosswise, is designed using reversible logic gates, which is the first of its kind. Also in this paper we propose a new reversible unsigned division circuit. This circuit is designed using reversible components like reversible parallel adder, reversible left-shift register, reversible multiplexer, reversible n-bit register with parallel load line. The reversible vedic multiplier and reversible divider modules have been written in Verilog HDL and then synthesized and simulated using Xilinx ISE 9.2i. This reversible vedic multiplier results shows less delay and less power consumption by comparing with array multiplier.
With ever increasing applications in mobile communications and portable equipment, the demand for low-power, high-performance VLSI systems is steadily increasing. Digital signal processors and application specific integrated circuits rely on the efficient implementation of arithmetic circuits (adder and multiplier) to execute dedicated algorithms such as convolution, correlation and filtering . A multiplier design using decomposition logic is presented here which improves speed when compared to the tree structured Dadda multiplier with very little power penalty. Pipelining is often used to improve the throughput of a design. A novel concept of modifying an adder to have latched outputs is presented to reduce the overheads of implementing pipelined structures.
Abstract: Given the importance of electric machines in the industry with high efficiency, and speed control of this machines are also important, in this paper, three-phase line start permanent magnet synchronous motor and three-phase induction motors that are same in nominal power and the number of poles, is controled, monitored and compared by open-loop voltage to frequency drive, with each other. To this end, simulating the same conditions for the launch of electronic drive with open loop control V/Hz with constant load torque is provided.Simulation results from MATLAB/Simulink software are presented for both line- starting and Adjustable Speed Drive (ASD) applications in the same situations, to provide a comprehensive comparison, and it shows a transient and steady-state response of an LSPMSM drive compared to its IM.
ABSTRACT: The multifunctional use of power transmission line provides a cost effective method for data and voice signal transmission, besides the power transfer of electric utilities. It utilizes the existing infrastructure of electric utilities and electricity consumers by using the multi access carrier digital communication technology. Broadband over powerline is one of the technology uses the existing electric transmission line as a carrier channel for the delivery of Broadband to the consumer. However, the technology meets the drawback that the electric wires might radiate electromagnetic waves at high frequencies. The power-lines are designed to distribute power in an efficient way, hence it is not adapted for communication. The high-speed data transmission power lines require appropriate digital communication techniques that efficiently use the available frequency band. Orthogonal Frequency Division Multiplexing (OFDM), as a type of multicarrier modulation, has become one of the preferred communication schemes to achieve reliable high-rate data transmission. In this paper, designed and presented the broadband over power-line using OFDM method for modulation and multiplexing the signal. Also, the mathematical model which takes into account the coupling equipment and transmission line has been developed. The simulation studies for the combined system and the OFDM has been carried out using MATLAB code.
Este trabalho aborda a tecnologia de transmissão de dados PowerLine Communication, apresentando seu funcionamento, seus tipos e aplicabilidade de uso. O estudo de caso desenvolvido para avaliação desta tecnologia se limitou à expansão de uma rede local usando a tecnologia PowerLine Indoor Communication, que tem apresentado crescimento mundial em seu uso. Foi efetuada uma análise da qualidade de serviço, através de testes realizados no laboratório de informática da Escola de Ensino Fundamental Coronel Virgílio Távora, onde se analisou as métricas de vazão, latência e perda de pacotes. Testes estes feitos de forma comparativa entre o padrão de rede Ethernet Category 5e e o PowerLine Indoor Communication HomePlug AV. Foi observada uma vantagem enorme para o padrão Ethernet Category 5e em termos de taxa de transferência e baixa latência. Por outro lado, nos testes, o PowerLine Indoor Communication manteve assim como o padrão Ethernet Category 5e, uma taxa nula na perda de pacotes. Outra análise realizada, foi a de qualidade de experiência, em que usuários que utilizaram esta tecnologia em suas residências, foram entrevistados, e por meio de um formulário, elaborado de forma subjetiva, avaliaram e relataram suas experiências. Como resultado, foi relatada uma experiência de uso satisfatória, aproveitando todos os benefícios que a tecnologia proporciona, e ainda recomendando para outras pessoas. Outro fator interessante foi o uso do PowerLine Indoor Communication em conjunto com o Wi-Fi, expandindo o alcance das redes sem fio. Por fim, conclui-se que o PowerLine Indoor Communication, é uma tecnologia recomendada para o uso em ambientes onde não há necessidade de grande tráfego de dados e nem de uma latência baixa, mas onde deseja-se expandir o alcance da rede local de forma fácil e eficiente.
feed: 0.05 mm/rev and depth of cut: 0.4 mm respectively. Analysis of variance (ANOVA) was used for analyse the influence of process parameters on multi responses. From the analysis it is concluded that, speed has high influence (F= 34.18, P= 0.025<0.05) in getting the optimized values of multi responses and the depth of cut has very low influence (F= 1.34, P=0.427>0.05). Regression models were developed for R a , R q and R z , which are
In the field of radio receivers, down-conversion methods usually rely on one (or more) explicit mixing stage(s) before the analog-to-digital converter (ADC). These stages not only contribute to the overall power consumption but also have an impact on area and can compromise the converter’s performance in terms of noise and lin- earity. As an alternative, we propose a receiver architecture that considers the ADC as both a quantizer and a down-converter block. This is achieved through the use of a variable reference signal (in this case, a voltage), as opposed to classic time- invariant reference signals. When embedded into a charge-sharing (CS) successive approximation register (SAR) ADC, this varying reference voltage is “saved” in the digital-to-analog converter (DAC) capacitor bank during the sampling phase, pre- venting any conversion errors. Furthermore, a phase-locked loop (PLL) is used in order to provide an on-chip solution for the generation of this variable reference voltage, which also removes the need for dedicated bandgap circuits and reference buffers. Post-layout simulations of an 8-bit 50 MS/s CS-SAR ADC show that the pro- posed “embedded mixing” technique is able to downconvert a high-frequency signal whilst also increasing the effective-resolution by around 0.5 bits, when compared to a standard DC reference voltage.
Nowadays, blackouts or sags of a conductor are threatening the safety and stable run of the power transmission lines. These phenomena happen due to the environmental conditions which change over the time, such as aging or temperature variations, precipitation and hotspots of power transmission lines as a result of extreme weather conditions. A precipitation condition result loses of heat from transmission line. Besides, the conductor aging and hotspots of a transmission line can lead to the loss of conductor strength, which may increase the probability of blackouts. All the damage suffers by the transmission line will cause the service interruption and required high cost to repair. Consequently, appropriate methods are required to monitor the condition of power transmission lines where the segment of the power transmission line which requires more repair or reinforcement can be identified early. This research work introduces the new novel to identify the critical aging segments and the hotspot power transmission lines. This method depends on the information about the power transmission line and its environment such as temperature variations and characteristics of the conductors. Besides that, the effect of the weather and radiative parameters on the conductor temperature are being considered as well in this research. The results in this research work had discovered the most significant impacts the conductor aging behaviour was conductor temperature. Convection heat loss is more consequential that radiation heat loss in terms of determination the conductor temperature.
By applying the finite volume method we have determined the electromagnetic field distribution of three-phase AC line, taking into account the temporal variation of the phase voltages determined by the frequency of the alternating current. We have determined the capacitance and inductance values of the three- phase line for different suspension configurations of conductors. We have obtained the numerical values of the linear parameters showing the obvious differences depending on the constructive realization and differences in
environment, cause significant variations in performance, the ultra low power approach lies on the biasing of tran- sistor bodies to adjust thresholds . The primary draw- backs to ultra low power CMOS are that it requires (i) a change in the fabrication process, (ii) additional circuitry to adjust body potential, and (iii) additional routing of separate well-voltage (V p-well and V n-well ) references.
In Internet, there are some machines responsible for transmitting data packets, and other that take off these packets from the queue. If the sender machine sends a data packet rate much more important than the rate of the receiver, network congestion is produced, hence, a congestion control will limit the quantity of input information with a lower rate than the transmission one to guarantee a good performance as well as a network protection against overloading and blocking. The high number of highspeed congestion control protocols led us to prepare this research work, which focuses on evaluating and comparing highspeed congestion control protocols. This paper is organized as follows:
Partitional : Given a database of objects, a partitional clustering algorithm constructs k partitions of n the data, where each cluster optimizes a clustering criterion, such as the minimization of the sum of squared distance from the mean within each cluster. One of the issues with such algorithms is their high complexity, as some of them exhaustively enumerate all possible groupings and try to find the global optimum. Even for a small number of objects, the number of partitions is huge. That’s why, common solutions start with an initial, usually random, partition and proceed with its refinement. A better practice would be to run the Partitional algorithm for different sets of initial _ points (considered as representatives) and investigate whether all solutions lead to the same final partition. Partitional Clustering algorithms try to locally improve a certain criterion. First, they compute the values of the similarity or distance, they order the results, and pick the one that optimizes the criterion. Hence, the majority of them could be considered as greedy-like algorithms.
Abstract: This study is concerned with a practical application of distributed artificial intelligence for managing the high data rate bus structured local area computer network that uses deterministic multiple access protocol. In the selected network that is managed using distributed artificial intelligence, the dynamic sharing of the available bandwidth among stations is achieved by forming “train to which each station may append a packet after issuing a reservation. Reservation and packet transmissions are governed by the reception of control packets (token) issued by the network end stations. Managing approach that was suggested depends on using intelligent autonomous agents, which are responsible for various tasks among it: election of the end stations, the recovery from failures, and the insertion of new stations in the network. All these tasks are based on the use of special tokens.
Also related is Pimentel et al. (2007), with a HSR investment valuation model using the real options framework, when only HSR demand faces uncertainty. We extend their model in order to allow positive or negative chocks in HSR demand level. In financial literature, ROA appears mostly in natural resources investments. Transportation investment analysis rarely incorporates real option theory. When does, use discrete time frameworks. As a result, this paper will introduce the transportation investment analysis of the HSR investment valuation in continuous time with stochastic demand facing random shocks, providing some closed form solutions. Our aim is to fill in this gap in the literature. Although Pereira et al. (2006) studied these issues, their work focused on airport construction. Our ROA framework will support the utility balance for the user between different rail speed services.
The present paper investigates the process of decision making regarding the optimal timing to invest in the highspeed rail (HSR) project, under uncertainty, using the real options analysis (ROA) framework. It’s developed a continuous time framework that allows a solution to the problem concerning the optimal timing to invest and to value the impact of the option to defer in the overall valuation of the project, with multiple uncertainty factors. Besides considering a stochastic demand, the effect of uncertainty in the investment’s expenditure and over the benefit per user is incorporated in a model with three stochastic variables. The modelling approach used is based on the differential utility provided to railway users by the HSR service.
Abstract : Elliptic curve cryptography plays a crucial role in networking and communication security. ECC have evolved in the recent past as an important alternative to established systems like RSA. This paper describes the implementation of an elliptic curve coprocessor based on the FPGA , which can provide a significant speedup for these cryptosystems. The FPGA configuration file is synthesized from VHDL code applying different hardware synthesis products. The implementation of ECC lies in three levels: scalar multiplication, point addition/doubling and finite field modular arithmetic. In this paper, we present a novel fast architecture for the point addition/doubling level in the projective coordinate. The proposed Architecture is based on Binary Field. The Design performs multiplication using Polynomial Basis. Analysis shows that, with reasonable hardware overhead, our architecture can achieve a high speedup for the point addition operation and point Doubling operation.Furthermore, the architecture is parameterized for different data widths to evaluate the optimal resource utilization.
Resonant tunneling diode (RTD) integration with photo detector (PD) from epi-layer design shows great potential for combining terahertz (THz) RTD electronic source with highspeed optical modulation. With an optimized layer structure, the RTD-PD presented in the paper shows high stationary responsivity of 5 A/W at 1310 nm wavelength. Highpower microwave/mm-wave RTD-PD optoelectronic oscillators are proposed. The circuitry employs two RTD-PD devices in parallel. The oscillation frequencies range from 20-44 GHz with maximum attainable power about 1 mW at 34/37/44GHz. Keywords: resonant tunneling diode, photo diode, oscillator, photodetector