Vol. 23 No. 3 (2015)
Articles
Abstract: Scour process at the abutment of bridge is influenced by the contraction of the stream flow specially when the abutment immureaneffectivewidth of the stream flow,also the shape of the abutment has an important effects onthescour depth at the abutment.In this paper a series of laboratory experiments were carried outto study the effect of contraction ratio and abutment shape on the scour and its maximum depth at the abutment.Threeshapes of abutments with three-contraction ratio with differentflow rateswere used.The result of the experiments showed that the circular shape and (30o) angle abutments reduce scour compared with that, which was, occur at the rectangular abutment.The reduction of scour depth with circular shape is about (22%) where that with (30o) angle is about (27%),also a dimensionless general empirical formula was createdfor thecalculation the scour depth by using the (SPSS 11.5) Statistical program a Coefficient (R2=0.933) of determination.
Abstract: Deciles method is one of the indices which are used for studying and analysing of droughts in the world and especially in Australia. The method is known by its simplicity and the limited data needed for analysis, and up to the knowledge of the authors this paper is the first study which utilizes this method for drought analysis in Iraq.Deciles method is usedin this research for meteorological drought investigation in Northern Iraq. Monthly rainfall data is collected and utilized from 9 meteorological stations scattered in the study area which are; Sinjar, Tel-Afer, Dohuk, Mosul, Erbil, Kirkuk, Dokan, Sulymania, and Derbendikhan for the period 1937-2010. The meteorological drought cases were studied and analyzedusing a table proposed in this study. The tableincludes the proposedmaximum and minimum rainfall depths for each decile and for each station involved in the study. This table can be used to identifyingdrought periods’ set on and termination in future. This can be achieved by comparing the actual rainfall depths in a certain area with the proposed tabulated values to diagnose drought cases which help in taking suitable actions for drought mitigation in advance. The drought analysis for the study area showed that the area has faced a sequential drought periods which were recurring about every decade and the most severe drought periods were in 1997-2001 and 2007-2010.
Abstract: The different types of mathematical models which are physically based models or the models based on laboratory experimental and/or field measurements are considered to estimate the runoff depth and runoff coefficient relating rainfall to runoff especially for the non-measured watersheds. Soil and Water Assessment Tool (SWAT) was applied to estimate the surface runoff depth of Al-Khoser River watershed, 696km2. The model was calibrated based on measured single storms data at the watershed outlet, while data measured at the outlet of sub watershed (36km2) are considered for model verification. For model calibration, the resultant values are 0.99, 0.95, 0.73 and 0.19 for determination coefficient,index of agreement, model efficiency, and t-test respectively, while verification of the model revealed values of 0.97, 0.89, 0.72 and 0.32 for the same parameters considered respectively. The model was applied as a daily continuous simulation for the period 1991-2011. Relationships between the accumulated daily runoff depths and accumulated daily rainfall depths have been obtained, additionally the yearly runoff depth related to the yearly rainfall depthwas also derived. Those relations can be used to estimate the runoff depth and runoff coefficient for different studies of the watershed.
Abstract: A stress analysis in the draw- bar during the tillage operation in two different types of soils and speeds has been carried out. The analysis of the soil types was conducted in the laboratory of Civil Engineering, University of Mosul. This analysis revealed two types of soils : clay and mixed, The material of the draw-bar and its mechanical properties were obtained. Then the stresses generated in small scale modelwere obtained using the finite element analysis using the “Ansys Release 14.0” program.Three dimensional stresses together with the equivalent Von-Mises and principal stresses have been obtained. The percentage deformation in the x,y and z direction were also obtained. During the operational stage, the stresses were measured using a number of electrical resistance strain gauges type PL-15-11 fixed on both sides of the draw-bar while the tractor was driven in two different soils at varies speeds (2.39, 3.37, 6.35) km/h. It was observed that the stresses were higher in clay soil more than those in a mixed soil due to the different composition in soil this will create different resistance in both types of soil . It was also observed that stresses increased with increasing speeds due to increase in momentum
Abstract: Abstract This research investigateswindcatcher usage in Mosul for ventilation . The choice of a squareshape windcatcher diagonally partitioned along its height attached to a room of dimensions 4x6x4 m. Indoorair motion speed and movement were studied to assess a windcatcher’s performance .A computational model is used with Autodesk Simulation CFD software for the simulation case. Part of this study was dedicated to find the geometrical characteristics of the windcatcherparameters: - height (4 cases), cross-section (3 cases) and location with respect to the room (4 cases).Another part is to analyze a yearly weather data of Mosul to find the prevailing speed and direction for all cases (a range of 20-30oC is chosen as a thermal comfort temperature range) and to use them as an input forthe simulation to find the best case of the windcatcher. The results shows that the best heights of 4m , the best cross-section of 1x1 m and the best location of the wind catcher isfound to be at the middle of long side of the room. The weather data shows that the prevailing wind speedbetween 1.62 to 4.83 m/s. The final result of the study confirm that the direction of the windcatcher and the room which can give the best performance using all the above selected parameters in Mosul is 337 oNNW.
Abstract: In urban areas, tunneling may induce ground movements which distort and damage overlying buildings and services founded on different geological formations.The objective of this study is to examine the effect of horizontal distance between the center of tunnel and the surface buildings. The study has been achieved using3D-FEM with the aid of PLAXIS 3D Tunnel code. The parametric studies including the horizontal distance between centerline of tunnel and the center of loaded area by taking five different distances that as ratios of distance to tunnel diameter(X/D= 0, 1, 3, 7 and 10). Three different geological formations have been selected that clay, sand and rock. In addition, three type of surface loadings have been adopted that greenfield, uniform pressure and piles.The results show that the surface subsidence decreasing with the increasing in the horizontal distance between the centerline of tunnel and the center of surface load. The maximum subsidence occurs when the center of tunnel sited under the edge of building (uniform pressure or piles), i.e. when (X/D=1). Then, the effect of tunnel vanished when it is at a distance of (3D) from the building. The greatest effect of the distance observed in case of pile group in sandy soil by increasing of (52%) in settlement over the unloaded one. The subsidence being uniform when the centerline of tunnel coincides with the center of building (X/D=0), while a differential subsidence has been obtained when the distance increases, i.e. X/D > 0.
Abstract: The Educational Campus in Mosul city is suffering from many problems with its transportation system ,due to lack of planning process and continuing studies either comprehensive one, in addition to the rapid growth of the use of personal vehicles with the decline in public transport services and the lack of any improvements of the road network too. The study aims to find out an equilibrium point of the transportation system at the intersection of the demand curve with supply curve, which represents the cost of services to be subsidized and availability of facilities on the network. Methodology started with collecting data, which includes statistical information for the community for the purpose of sample size and sampling process. The distributed questionnaire forms that was designed to gather information on trips and the knowledge of the properties of trip characteristics was done. Then cost was found about the demand curve calculated operating costs for vehicles, in addition to the cost time and cost environmental impact. Either curved processing evolved to include the cost of the vehicle and the cost of investment and maintenance, and cost of construction of the road in addition to the time savings .Statisticalanalysis was employed to find the correlation between variables. Linear regression between the independent variables and the dependent variables were identifiedas the most influential independent variables in addition to the best equations and mathematical relationships representative of the cost and demand processing. Research has come to several important conclusions to improve transport with the modes used .The proportion of public transit users are (38 %) compared with the majority of users of taxis by(43%), and finally representing users of the passenger car user about (18%) of the total sample , the representing students ratio (75.8%) of the users of the bus , also obtained data vehicle occupancy according to each mode. The final results show that the equilibrium point for each person is 1.0 $ for PC with average travel time = 35 min, and 0.6 $ for taxi with travel time = 60 min, and 0.32$ for small bus with travel time = 105 min, finally for large bus =0.085 $ with travel time = 75 min.
Abstract: Abstract The specific patterns of daily activities routine in houses for each society varies according to differences of its culture , believes ,rituals and traditions . which reflects the varity of houses type and physical characteristics of size , number of fundamental living spaces. Houses we live are not only physical structures containing our daily routines activities , they are integral part of our cultural system , then Domestic space is spatial boundary that frame our living activities along the day according to our culture and behavioral codes that determines the way space is used and claimed within the home . This article aim to represent the properties of domestic space within local houses . its limitation , prospects ,obstructions and barriers for daily living activities ,Building in general and house in particular , information control achieved through visual field are a part of privacy – territory living activities , which regulate the amount and level of interpersonal interaction between inhabitants. The purpose of this research is toanalyzeIsovist graph for domestic spaces by applying Depth map software in order to get reflection of visual physical characteristic on level of choice daily activities for all members of Mosul family. The study concludes that the visual structure of domestic spaces enhanced spatial permeability structure and affected of the capability of activity choice
Abstract: In the lastyearsof thiscentury, many of the research centers continue to do many experimental studies with cognitive nature in the field of design process that had wide range of applications in the architectural domain, to explore how the designer think and perform during the design process and on which aspects the designer depend during that process.Thiscanbeattributed tomanycauses are;the intimate need for"Corporatearchitecture"which became the rule of communication between the designersand clientsnow.Theincrease of the designers justification abilities and capabilities the promotion oftheirroleasKeydecisionmakersonaprojects.Finally, therole of computer technology asadesigntool that helpsindesignprocessandbecomes congenial to a designer's thinking and working procedures in order to grow and develop such atool, which will be supportive for architectural field. This paper puts forward an experimental study comparing the cognitive processes during conceptual design stage for three different types of design tasks performed by a group of architectural design students, to explore the effect of the different design tasks on the concept framework of those students during conceptual design activities.
Abstract: This paper presents an air gap eccentricity fault Diagnosis of a salient Pole three phase synchronous generator. The detection and diagnosis of this type of fault is based on analyzing armature and field current signatures, using FFT . Therefore, the synchronous generator, under this type of fault, is modeled by using finite element method (FEM). Also practical results are performed in the lab with deliberately air gap eccentricity faults, by using samples of bearings malfunctioning or the removal of single or pair pole. The modeling and experimental results show that FEM is a reliable approach that can be used to model synchronous generator under electrical and mechanical faults
Abstract: In this research, measurements of total (TSP) and fine suspended particulate PM1, PM2.5, PM7 and PM10atBadoosh cement factory were carried out. Seventeen locations inside the factory are selected. The effect on soil around the cement factory was also studied by collecting samples in the four directions North, South, East and West to a distance of five kilometers from the factory with one kilometer spacing. The result of the study revealed that;the concentration of very fine suspended particulate PM2.5 was over the international standard limits at different locations of the factory and the overall average concentration for the factory was (47 g/m3). For PM10 suspended particulates, the results at all locations were over the international limits and the overall average concentration reached 869 g/m3, which was much more than the standards of 150 g/m3. On the other hand, the total suspended particulate concentration exceed the standard at several locations in the factory. Significant correlations were found among the suspended particulate concentrations according to their size.The results of soil test around the cement factory showed significant differences of oxides percentages among the directions. Higher percentages were recorded in the South and East directionsthan North-West direction. The results also revealed that the percentages of SiO2 and Al2O3 were 40.94% and 10.53% in the east direction whereas higher percentage for Fe2O3 (4.86%), CaO (36.81%), MgO (4.49%),and SO3(0.76%) were recorded in the south direction of factory.
Abstract: Training of Artificial Neural Networks (ANNs) for large data sets is a time consuming mission. In this paper, accelerating the training of artificial neural networkis achievedby a parallel training using either Multicore Central Processing Unit(CPU) orGeneral Purpose Graphics Processing Unit (GPGPU). The trainingis implemented using five datasets with diverse amounts of patterns and with different neural network parameters in Multilayer Perceptron (MLP). The results show a significant increase in computation speed, which is increasednearly linear with the number of cores in multicore processor for problems with medium and large training datasets.Also, a considerable speed up is achieved when the GPU is used to train the MLP withthe large training datasets. While a single core processor is a better choice when the data set size is small.The optimal number of cores or the type of the parallel platform should be employed according to the load of computation.
Abstract: In this paper, the design of an efficientbio 9/7 filter bank for the discrete wavelet transform(DWT) is proposed. The design starts with the standard design constraints of the lifting scheme architecture. A modification in the resulting 9/7 filter bank coefficients after lifting is made leading to new sets of simple and less-number coefficients for both low-pass and high-pass branches of the direct structure of the DWT filter bank.In order to speed up the operations of the designed filter bank, the need for multipliersis eliminatedby realizing the designed filter coefficients in a multiplier-less manner. That’s each of the existing non-zero coefficient is represented as sum-of-powers-of-two (SOPOT). The complexity of resulting bio 9/7 filter bank structure is the lowestamong other recent issued structures. The performance of resulting structure is then examined objectively by applying three different test images and computing the peak signal-to-noise-ratio (PSNR) values for the reconstructed image.Subjective evaluation of these imagesis also achieved by calculating the average mean opinion score (MOS). Objective and subjective evaluation indicate the eligibility of the designed bio 9/7 DWT filter bank for image processing.
Abstract: LTE networks are the latest generation of wireless networks based on IP architecture; it is standardized by the 3GPP in its Rel.8. LTE networks are implemented practically to access internet with very high data rates with using various multimedia services.This paper is based on five types of downlink packet scheduling algorithms in LTE networks,It examines the impact of throughput, the fairness and the spectral efficiency of each scheduling algorithms when the speed of UE (User Equipment) and the number of UEs are changed. A comparison between the scheduling algorithms has been done using Vienna LTE SYSTEM LEVEL Simulator.
Abstract: Imaging becomes an advantageous technical tool in the recent decades. It enables many scientists to understand different phenomena. However, there are many high-speed phenomena that cannot be imaged using a commercial non – scientific camerasdue to their low capturing speed compared to the phenomenon's. Such phenomenon, needs high-speed expensive cameras. Some of those phenomena can be monitored if the imaging speed of the current commercial cameras isslightly increased. Consequently, it is possible to increase the speed of the video recording for a commercial cheap camera using crank and piston mechanism. A phenomenon faster than the speed of the current commercial cameras had been created and captured with the aid of the present enhancement. Two casesare compared. In the first case, the phenomenon was at a speed faster than the imaging capability of the camera and without using the present mechanism. In the second case, the phenomenon speed was kept constant but the camera is now fixed on the piston. As expected, the video capturing process enhanced and the captured images are seen to be clearer by means of a visual qualitative (mere eyes) observation between the images of the two cases.
Abstract: An experimental study of Kevlar-29/epoxy composite thin wall cylinders under internal pressure loadinghas been investigated in this work. Kevlar/epoxy composite specimens were fabricated and tested. Specimens were tested using the hydraulic pump and subjected to a static internal pressure.The results obtained from this work to find the pressure increase ratio and the failure load were found and a comparison has been achieved.According to the comparison results the tough material was specified. The efficient and effective composite cylinders have been tested experimentally. And this provided a considerable advantage over using a woven roving fiber in pressure vessels applications.