Algorithmic skeletons are widely used to manage multi-processor computations but are most effective when deployed for regular problems on homogeneous systems, where tasks may be divided evenly without regard for processor characteristics. With the growth in heterogeneity, where a multicore is coupled with GPUs, skeletons become layered and simple task distribution becomes sub-optimal. We explore heterogeneous skeletons which use a simple cost model based on a small number of key architecture characteristics to find good task distributions on heterogeneous multicore architectures. We present a new extension to an existing skeleton library associated cost model that enable GPUs to be exploited as general purpose multi-processor devices in heterogeneous multicore/GPU systems. The extended cost model is used to automatically find a good distribution for both a single heterogeneous multicore/GPU node, and clusters of heterogeneous multicore/GPU nodes

Parallel, Skeleton, Heterogeneous, Cost model, multicore, GPU ,Algorithms, Design, Performance

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Short-term load prediction, neural networks, RBFNN, NARXNN, BPNN, MAPE, Matlab. ,vcv

Crystalline silicon photovoltaic modules are being used for long time in many photovoltaic applications. It was not expected that photovoltaic modules of old technology will last for twenty years. In contrast, a photovoltaic system which was installed in 1979 in the Libyan Desert is still running with a little decrease in the output power and small changes in its designed parameters. The study goal is to evaluate the performance of thirty-year old crystalline silicon cells under Standard test condition. Some of the solar cells were dismantled from one of the photovoltaic modules which have been working for more than thirty years in order to test and measure their current-voltage curve. This paper presents the measuring results of indoor measurements on the thirty-year old solar cells

standard test condition, Qualification and Testing, solar cells ,

Wheelsets are one of the most expensive components through the life of a rail vehicle. They require regular maintenance activities such as reprofiling on a wheel lathe, inspection for safety-critical damage to wheel and axle, and renewal of wheelset. There are several reasons for reprofiling such as tread wear, flange wear, and thermal; while, the cost of changing damaged rails is much greater than that of changing any other damaged part of track. The wheel and rail damage has been a concern in railway systems for several decades. The change of wheel profile and rail profile makes a large contribution to track maintenance cost. The develop a new method to measure the wheel/rail surface roughness can assist to improve the design of wheel and rail profiles, where the wheel/rail surface roughness is correlated to wheel/rail safety and economy. Therefore, the main aim of this work is to develop a new method for measuring wheel/rail roughness parameters using Dektak profilometer and replica material. The replica technique is very useful for situations in which it difficult to get to the surface in order to measure it, such as when the specimen is large; it is also useful when the components change due to wear and mechanical actions and the record of the original surface is needed. In this paper, the replica material which was applied to the wheel and rail surfaces of the twin disc test rig to make a copy of wheel and rail; then, the replica samples were measured using Dektak profilometer and the results were processed to establish wheel and rail roughness parameters.

wheel and rail roughness, measurements, Dektak profilometer, replica material, twin disc rig ,

This paper presents algorithms implementation of substitution cipher on a FPGA “Field Programming Gate Arrays”, FPGA provides faster data rate, more flexibility to make changes to the programme and better physical security than other hardware.The design was coded, simulated and tested by MATLAB /Simulink and Xilinx system generator and implemented on Xilinx Spartan 3A DSP XC3SD3400A -4CSG84C hardware implanted and test by using Xilinx ISE 12.4.

Decryption, Encryption, FPGA, MATLAB, Substitution Cipher, Xilinx ,

Data compression is a process that reduces the data size, removing the excessive information and redundancy. It is a common and important requirement for most of the computerized applications, it can shorter the data size, which lead to cost reduction. The main purpose of data compression is to remove data redundancy from the store or transmitting data, it is also an important application in file storage field and distributed system. Data compression techniques are can be used in different data formats such as text, audio, video and image files. The aim of the study is to compare between many of the Lossless data compression techniques and compare their performance. There are many techniques of data compression and they can be categorized as Lossy and Lossless Compression methods. In this study a Run-length encoding, Huffman Coding, Shannon-Fano Coding, and LZW Encoding algorithm were used, their performance were compared by using data compression in the text format, the compression ratio, compression factor and saving percentage were calculated. Compression ratio in Huffman coding and Shannon-Fano coding where less than Run-length encoding and LZW encoding (38%, 40%, %81, 74%) respectively, while compression factor where higher than Run-length encoding and LZW encoding (2.63, 2.48, 1.23, 1.35) respectively, the results of saving percentage by using Huffman coding and Shannon-Fano coding where higher than Run-length encoding and LZW encoding (62%,60%, 19%, 26%) respectively. The study pointed to the effectiveness of Huffman and Shannon-Fano coding reducing the size of the files compare to other algorithms.

Data compression, Lossless data compression technique, Huffman Coding, Run length encoding, Shannon-Fano coding, LZW encoding. ,