Vol. 21 No. 4 (2013)
Articles
Abstract: Abstract In this research an experimental study was conducted to explore the effect of high temperature on the some mechanical properties such as compressive strength and splitting tensile strength of concrete with added silica fume and reinforced with glass fiber and it as compared with normal concrete. Mixes were prepared by adding silica fume of (0%,5%,10%,15%,20%) by weight and glass fiber of (0%,0.75%,1%,1.5%,1.75%) by volume . Compressive strength and tensile strength of mortar with the same percentage of silica fume and glass fiber was also studied. The result shown increased concrete compressive strength with increased of silica fume until (15%) and decreased at (20%) for both cases with and without heat . Also results shown increased concrete compressive strength with increased of glass fiber until (1%) and decreased at (1.5%,1.75%) for both cases with and without heat. Keywords :Compressive and Tensile strength, Glass fiber, High temperature, Silica fume
Abstract: In this study, the effect of number of carbon layer, its position and orientation angle of the laminate on the natural frequency and mode shape for hybrid fiber (carbon/glass) with epoxy composite laminates are investigated. Numerical analyses are carried outto study vibrationbehavior of composite laminated beams using ANSYS 13 software.The results show that the natural frequencies increased when the number of carbon layerincreases and decreased when the carbon layer position changes from the surface towards mid-plane, also; the natural frequencies change with changing orientation angle. Keywords: natural frequency, composite beam, vibration analysis, FEM
Abstract: Abstract No one can deny the fact that cracked plates modeling is important to detect structural damage. The strength calculation of different constructions is troubled by various defects, which accelerate the formation of cracks as well as the process of fracture. This research presents a comparison between the results obtained by FEA techniques for isotropic and orthotropic plates,, general solutions for model-based approach which represents the cracked plates that subjected to a tensile load for determining the stresses,,. The finite element formulation is carried out in the using analysis section of the "ANSYS 12" package to obtain the stresses and compare the results. Keywords: Finite Element, Cracks Simulation, ANSYS, Plates.
Abstract: Abstract The aim of this study is to know some of hot-mix-asphalt characteristics and performance, which use in the surface layer with fine aggregate gradation in flexible pavement by using Bejee Asphalt of grade 40-50 as a binder through administration experimental tests. The first stage including the experimental tests is to calculate the physical properties of the basic components of the asphalt mixture, and to make sureit'scompatible with the standards and the eligibility of usage. Then find the ratio of mixing by using Marshall Method to design the asphalt mixture. In the second stage, the experimental tests were conducted to determine the properties of the performance, and the effecting factors, which include, the repeated load test,the static load test, and then cohesion test.The resilient modulus of the asphalt mixture was found using repeated load test for the values of resilient modulus, were in positive relation with the applied pressure and inversely proportional with both the temperature and asphalt percentage in the mixture, the values of Resilient Modulus is varying between 423856,206625Psi.The test of static load calculate the total strain and stiffness of displacement and the total resulting displacement where the reaction increases and the distortion both increase according to the increase of temperature and applied pressure inversely proportional with stiffness values and positively with displacement values, stiffness values for mixtures in study varying between1.05×〖10〗^6, 4.28×〖10〗^6Kpa.Thecohesion coefficient for hot-mix-asphalt wascalculated to know the effect of asphalt content on mixture cohesion under grading different thermal.The results showed the increase of the values of cohesion coefficient with increasing of asphalt percentage, then began to decrease, whereas it inversely proportional with temperature.
Abstract: Abstract Emissions from diesel engines(rail, marine, construction equipment and other non-roadmobile sources) presently account for a significant part of themajor pollutants (SOx, NOx, VOC, PM, CO, and noise) thatare responsible for smog and for human health impacts. The objective of this work is to identify effective ways to reduce emissions from direct injection Fiat diesel engine.The approach used here is the combustion of water-diesel emulsion in diesel engine, at different water ratios, at constant engine speed and variable engine load. The second set of tests was at constant load and variable engine speed. The results show improvement in NOx, UBHC, CO and CO2 reductions with increasing water emulsion percentage to 20%, accompanied with brake specific fuel consumption (BSFC) reduction also. Keywords: water-diesel emulsion, performance, emissions, PM, noise.
Abstract: Abstract In this paper an experimental work was conducted to study the effect of a weir height and location in a main channel on the head and discharge of branching channel connected upstream the weir, with three different angles (30 ̊, 60 ̊ and 90 ̊). The bed slope of the main and branch channel was kept constant and it was equal to 0.0002 and 0.0005, respectively. A variable height weir was fixed in the main channel at different distance (60, 90 and 120 cm) downstream the branching point. For each location, seven different discharges were used, and for each discharge, the height of the weir was changed from 2 to 10 cm. The results of the research showed an existence branching and main discharges, and a similar relation between branch discharge and the weir height. It is also found that the ratio of discharge (the branch discharge divided by main discharge) increases with increasing weir height, and the magnitude of this decreases as the discharge increases. The result also showed that the angle 60 ͦ of branch channel gave highest values for discharge ratio. The depth of water in the branch channel varies directly with the height of weir, and a maximum percentage of increases of depth observed in all experiments were 194%.
Abstract: Abstract This research deals with the optimum design of an absorption cooling system with cooling capacity of 2 ton refrigeratio driven by solar energy and using Lithium Bromide as absorbent and Water as refrigerant. The present system uses water for cooling the absorber, condenser and for heat transfer in the evaporator. A mathematical model is built to simulate a solar collector system and absorption system, in addition to design flat plate solar collector, f-chart method is used to find the optimum required solar collector area to air condition a space in the establishment with eight hour per working day. The coefficient of performance (COP) has been taken as a measurement to find the optimum internal operation conditions, by examining the performance of absorption system with varying temperatures to the generator, absorber, condenser, evaporator and effectiveness of a solution heat exchanger to obtain the optimum values of these operation conditions and also obtain maximum value of the COP. The result show that the collector area has a large effect on the actual useful heat gain and auxiliary heat to the system, and a collector area 26m2 is enough to operate absorption system more than eight hours by using a water storage tank with a capacity of 1.5 m3 and depending on weather data of Mosul city. The results also show that the generator temperature had a great effect on the absorption and solar collector systems. Keywords: absorption system, solar energy, water- lithium bromide solution, air conditioning, optimization.
Abstract: Abstract The rain water harvesting is an ancient art depends on catch and hold the rainfall by different shapes that field invented , basing on tremendous changing of the spatial and temporal probability of the rainfall . Spatial Expert Support System (SESS) is prominent to give the appropriate experience for searching the best location to construct the rain water harvesting techniques giving it the general view of different data for study area and how it can be arranged , storage and to layout by accurate professional maps . The geographic information system (GIS) ability makes this system integral by enter the data layers that concern of the data base and to layout it by general forms of the shape and concept. The programs (GLOBAL MAPPER V.11 ، ARCVIEW V.3.3 and ERDAS IMAGINE V. 11) are used to process the data base for a chosen study area called AL-Mlah basin valley northern of Iraq. And to prepare the engineering electronic map that can develop the actuality of the agriculture and irrigation in the study area .
Abstract: Abstract The goal of the paper is to obtain a good WLAN video conference services, including an increased number of users and reliable coverage area with minimum implementation cost. We presents a simulation study ( using OPNET Modeler 14.0 package) of a video conference services working over different wireless local area network (WLAN) standards (IEEE 802.11a and IEEE 802.11g) with two different modes of data transmission (multicast and multiple unicast). Also , we examined different video compression techniques to choose a suitable one to work on the system . Finally , a new WLAN access point architecture was used to enhance video conferencing performance and to maximize the number of its users . Practical implementation of a video conferencing system was achieved over WLAN when using classic and developed Access point .
Abstract: Abstract In this study a thermal analysis and performance evaluation was carried out to investigate the benefit of using steam injection technique to Mullah Abdullah simple gas turbine generators (North of Iraq). Mullah Abdullah simple gas turbine generators was modeled and simulated to observe its performance including power output, thermal efficiency and specific fuel consumption. Thereafter, the simulation was carried out to investigate the performance of the suggested unit when a steam injection technique is used. The suggested method has been investigated and its results compared with a simple cycle results. The results indicates that the power out of the present Mullah Abdullah simple gas turbine can be held constant (37.5 MW) even the ambient temperature increase from 15 °C to 45 °C for the whole year by injecting a suitable quantity of steam, depending on ambient temperature, in its combustion chamber. The injected steam is generated by the heat recovery steam generator which extracts the thermal energy available in the exhaust gases. Keywords:- Gas turbine, steam injection, heat recovery steam generator
Abstract: Abstract Interior design is considered as a concept that accompanied the theory and practice of architecture. It is represented as a form of manifestation of Architecture ,which influenced and affected by the intellectual trends and theory of architecture in their quest for the formation of modern architecture since the beginning of the twentieth century. This paper discusses the historical concept development of interior design in the period, in which modernism and postmodernism was formed. The aim of this paper to detect the most prominent aspects that define the concept of interior design, and down to determine the particularity of each movement with respect to the interior design vision. These aspects were: the nature of the interior design and essence, the goal of the design procedure,the relationship of interior design with interpretation, its sources, and its design determinants. Keywords: interior design, interior, interior space.
Abstract: Abstract In this paper, a filter bank structure for the implementation of infinite impulse response (IIR)discrete wavelet transform (DWT)is proposed. Bireciprocal lattice wave filters(BLWDFs) are utilized in a linear-phase design of 9th order IIR wavelet filter bank (FB). Each of the two branches in the structure of the BLWDF bank realizes an all-pass filter. Filters of this bank belong to the intermediate design group, maintaining linear-phase property with best roll-off characteristics in their frequency responses. The design is first simulated using Matlab7.10 programming in order to investigate the resulting wavelet filter properties and to find the suitable wordlength to represent the BLWDF’s coefficients in quantized forms for best selection of some prescribed performance measures. All adopted measures show an excellent closeness to some typical cases. Each coefficient in the resulting structure is realized in a multiplierless manner after representing it as sum-of-powers-of-two (SPT). Multiplications are then achieved by only shift and add. Multiplierless FPGA implementations of the proposed IIR wavelet filter banks are also achieved with less complexity and high operating frequency. Keywords: Bireciprocal Lattice Wave Filters (BLWDFs), Bireciprocal Lattice Wave Discrete Wavelet Filter Banks (BLW-DWFBs), IIR Wavelet Filter Banks, Scaling and Wavelet Functions, Linear Phase Processing, FPGA Implementations.
Abstract: Abstract In this paper, a filter bank structure for the implementation of infinite impulse response (IIR)discrete wavelet transform (DWT)is proposed. Bireciprocal lattice wave filters(BLWDFs) are utilized in a linear-phase design of 9th order IIR wavelet filter bank (FB). Each of the two branches in the structure of the BLWDF bank realizes an all-pass filter. Filters of this bank belong to the intermediate design group, maintaining linear-phase property with best roll-off characteristics in their frequency responses. The design is first simulated using Matlab7.10 programming in order to investigate the resulting wavelet filter properties and to find the suitable wordlength to represent the BLWDF’s coefficients in quantized forms for best selection of some prescribed performance measures. All adopted measures show an excellent closeness to some typical cases. Each coefficient in the resulting structure is realized in a multiplierless manner after representing it as sum-of-powers-of-two (SPT). Multiplications are then achieved by only shift and add. Multiplierless FPGA implementations of the proposed IIR wavelet filter banks are also achieved with less complexity and high operating frequency. Keywords: Bireciprocal Lattice Wave Filters (BLWDFs), Bireciprocal Lattice Wave Discrete Wavelet Filter Banks (BLW-DWFBs), IIR Wavelet Filter Banks, Scaling and Wavelet Functions, Linear Phase Processing, FPGA Implementations.
Abstract: Abstract In this paper, the DWT introduced through the design of the biorthogonal 5/3 filter bank using the lattice structure. The lattice coefficients of the proposed structure are very suitable for implementation using shift- only operations (with a single shift and add operation) instead of multipliers to perform multiplications. This results in a recognizable hardware saving when implementing such lattice structurehardwarly. The designed filter bank implemented using Matlab programming for verification. Matlab programsare also used to find the PSNR values that are taken for a group of standard gray scale images as objective criteria for efficiency, resulting in high PSNR values of around 55dB. The efficiency of the results also measured subjectively, for some standard gray scale images by comparing the original input images with the resulting onesfromcombining both analysis and synthesis sides of the proposed DWTstructure.Theefficient FPGA implementation of such design is consideredto show its simplicity. Keywords: Bio 5/3 Filter Bank, DWT,Lattice Structures,FPGA Implementation.
Abstract: Abstract Modulation recognition has been an important problem in both commercial and military wireless communication. Modulation recognition can be divided into two categories: identification between categories and identification in category. In this work a system is proposed for identification between categories of different digital modulated signals using a combination of discrete wavelet transform (DWT) and the linear predictive coding (LPC) with the probabilistic neural network (PNN) as a classification tool. It was found that the proposed system out performed any of the existing systems by using six DWT decomposition levels and 20 LPC coefficients. The symlet 20 wavelet filter proved to be the best candidate. The results showed that a 100% recognition can be achieved at a signal to noise ratio (SNR) of 2db for the digitally modulated signal. Keywords: Modulation recognition, Wavelet, linear predictive coding, Probabilistic neural network.
Abstract: Abstract In this paper the detection of human face and eye in still frontal color images is discussed. Firstly; the preprocessing required step is accomplished. It includes image resize, RGB to gray-scale conversion, image binarization, noise removing and small objects removing. Then a proposed algorithm is applied for face localization by detecting the face edges using the detection of the pixel color change in the binary image. Finally, the normalized cross correlation is applied to find the accurate position of eyes within the localized area of the face. Keywords: Eye detection, Face detection, Face recognition, Image processing, Pattern recognition.
Abstract: Abstract The transimpedance amplifier is realized in a 0.18μm CMOS technology. The TIA uses a shunt-shunt feedback topology, differential TIA because it reaches a higher bandwidth than a conventional one. The TIA also has a variable gain to increase the bandwidth of theamplifier . The TIA has a maximum gain of 73 dBΩ, bandwidth 3.1GHZ, bit rate 5Gb/s and input-referred current noise of 5 pA/√Hz. Eyejitter at bit rate 5Gb/s equal to 5ps (peak to peak). Keywords:transimpedance amplifier (TIA) , Berkeley Short Channel Igfet model (BSIM model) , Advanced design system (ADS) .
Abstract: Abstract The aim of this research is to calculate experimentally the coefficient of discharge for cutthroat flume. Nine models were contracted with different angles (α=30°, 45°, 60°), for each angle, Three ratios of width of cutthroat to width of channel Bc/B were used (Bc/B%=20, 33.3, 50); the slopes of the channel were changed five times (S=0.0, 0.001, 0.002, 0.003, 0.004) for each ratio. The results show that the coefficient of discharge Cd increases as the slope S increases, and as the ratio Bc/B, is the ratio of head of water through cutthroat to width of cutthroat hc/Bc, critical depth through cutthroat to width of cutthroat yc/Bc increases, and for a constant ratio Bc//B, Cd increases as α increase. An empirical model was predicted to calculate the Cd in terms of the perimeters ( S, hc/Bc, yc/Bc, Bc/B,, and α), finally the water surface profiles were drawn and there were in a continuous trend. Keyword: discharge coefficient, cutthroat flume