Vol. 18 No. 2 (2010)
Articles
Abstract: Abstruct The sheet meal forming are the most widely used in the metal industries. The forming limit curve(FLC) is considered as the important mean of measuring the formability of sheet metal. In this work the FLCs of pure Aluminum sheets, determined firstly by using hemispherical punch and die, and secondly by bulging, were compared. Also the effect of some factors on the FLC, such as thickness and annealing were studied, and a comparison was made between the FLCs determined by the two methods. It was shown that the formability determined by bulging is higher and this is due to the absence of friction during forming which lead to a more uniform strain distribution. Three sheets thickness were used(1,0.8 and 0.6) mm. It was found that the formability is increased with thickness in both methods. The best formability was of the sheet of 1mm thickness, deformed by bulging. Annealing improved formability and the better improvement was by bulging Keyword : Aluminum sheet - Forming limit diagram – Hydraulic Bulging
Abstract: The performance of direct torque controlled (DTC) induction motor system is greatly affected by the change of the motor stator resistance especially when the motor runs at low speeds. A new architecture of multi-basis wavenet-based model is proposed and implemented for stator resistance identification. Such multi-basis model utilizes multi-set daughter wavelets. By means of enough training of samples, the descent gradient algorithm is used to fulfill both system structure and parameters initialization, and the stator resistance is then acquired online with the operation of the system. The simulation results were carried out using Matlab/Simulink library and compared with those obtained from classical stator resistance identification method based on PI control and from another recent wavenet-based method. The simulation results show that the proposed method can improve the system performance. Keywords: Wavenet, Multi-basis wavenet, Direct torque control, Stator resistance, Induction motor.
Abstract: Abstract Wide range of industrial and engineering applications for graphite containing cast irons and the harmful effects of corrosion environments on these important engineering materials, make it necessary for continuous Scientific research in this field . In the current study, performed corrosion tests on Pearlitic cast irons using the sandy soil as the corrosion environment . The results obtained show a clear relationship between corrosion rate of graphite containing cast iron with shape of graphite. The graphite flakes in cast iron appeared to cause high corrosion rates compared with spheroidal or rosette graphites . The results also show that corrosion rates of spheroidal cast iron are slightly higher than malleable cast iron. The corrosion rates of grey cast iron represent the highest when compared with those of spheroidal and malleable cast iron. Keywords: Corrosion, Cast Iron, Sandy Soil
Abstract: Abstract The computer graphics system performance is increasing faster than any other computing application. The Geometric transformations and animation are one of the most important principle of the interactive computer graphics which are essential for modeling and viewing. This paper tends to construct a general form of matrix representation of the geometric transformations and implement it using Field Programmable Gate Array (FPGA). In addition to that the sine and cosine function evaluation is done using two techniques, the lookup table method and CORDIC algorithm. Keywords: lookup table, FPGA, geometric transformations, CORDIC.
Abstract: Abstract The study aims to develop a computer model for assessing the effect of uniformity and deficit irrigation on farm crop production. The formulation of the model is based on the concept of field water balance. The model was applied for a selected autumn crop (maize). Ready to use values of evapotranspiration in the selected site (Al-Jazeera irrigation project-Nenawah) were used. Also, a published field data for sprinkler water distribution uniformity was adopted in the study. The study revealed that the yield ratio deficit increases with the increase in soil moisture depletion but decreases with the increase in irrigation uniformity. The actual crop evapotranspiration increases with uniformity. The results of the study also showed that the relative water use efficiency under deficit irrigation increases with the increase in soil moisture percent depletion and irrigation deficit ratio. Keywords: Sprinkler irrigation, Irrigation uniformity, Deficit irrigation, Evapo-transpiration, Water use efficiency.
Abstract: Abstract The effect of anisotropic yield criteria is very efficient in theoretical determination of limits strain of forming limit diagram(FLD) for sheet metals. In this paper the forming limit diagrams for (AA5182/polypropylene/AA5182) [AA/PP/AA] sandwich sheets have been determined theoretically using Marciniak-Kuczynski analysis with different anisotropic yield functions (Hosford 1979 and Barlat & lian 1989). It is shown that the determination of forming limit curve using (Barlat & lian1989 criterion) with the (M-K) analysis , gave the best results compared with the other anisotropic yield criteria. Also the forming limit stress diagram is theoretically determined using Marciniak-Kuczynski analysis and (Hosford & Barlat-lian) yield criterion for sandwich sheets and AA5182 skin sheet. It is shown that the limit stress in experimental and theoretical forming limit stress curve for AA5182 skin sheet is higher than the limit stress in sandwich sheets. Keywords : Composite materials, forming limit diagram(FLD),forming limit stress diagram (FLSD), stretch forming , anisotropic yield criterion
Abstract: This research investigates open channel protection using gabions by conducting a series of laboratory tests on a trapezoidal channel with fixed width and bed slope. In this study, values of failure flowrates are obtained with a description of failure mode under the effect of changing channel side slope, gravel mean diameter, and number of protection layers. Three channel side slopes are tested (1V:1.5H, 1V:2H, and 1V:2.5H), with three gravel diameters (11.1, 15.9, and 22.25)mm, for one and two layers of protection. Two modes of failure have been observed namely sliding and overturning due to the movement of gravel inside the gabions. Results showed a direct relation between failure flowrate of protection layer and both gabion weight and number of protection layers. It has been obtained that failure flow rate increases with the decrease of channel side slopes. Equations have been obtained relating failure flowrate with both gabion weight and channel side slope. Empirical equations have been obtained using dimensional analysis to estimate failure flowrate as a function of uniform flow depth and gravel mean diameter. A design method has been proposed to protect channel side slopes using gabions. Keywords: open channels, gabions
Abstract: This paper studies the performance of side weirs by changing the end lip slope of this weir using three angles (00,30,60) opposite flow direction, depending on Froude number and slope of side weir end lip, an equation for the coefficient of discharge for the side weir has been defined. From the results it was found that the side weir inclined (30) decreases the water head above it by (8%), with respect to horizontal lip of side weir, while this value reach to (12%) when side weir lip inclined (60). This mean increasing the discharge pass over side weir by increasing slope of side weir end lip opposite flow direction, then this weir can be used as a good escape the surplus discharge as well as will be more economy when compared with the horizontal lip side weir. (for horizontal channel and subcritical flow). This paper studies the performance of side weirs by changing the end lip slope of this weir using three angles (00,30,60) opposite flow direction, depending on Froude number and slope of side weir end lip, an equation for the coefficient of discharge for the side weir has been defined. From the results it was found that the side weir inclined (30) decreases the water head above it by (8%), with respect to horizontal lip of side weir, while this value reach to (12%) when side weir lip inclined (60). This mean increasing the discharge pass over side weir by increasing slope of side weir end lip opposite flow direction, then this weir can be used as a good escape the surplus discharge as well as will be more economy when compared with the horizontal lip side weir. (for horizontal channel and subcritical flow).
Abstract: Abstract Contaminant movement through soil and groundwater contamination are one of the common environmental problems nowadays. Leakage of toxic fluids into the soil and groundwater could create a serious environmental problems. Most growing countries municipal use of open dumps directly without using lining for the solid waste disposal. The presence of groundwater near the waste landfill and its seasonal changes plays an important role in the contaminant transport on the surrounding sites. This necessitate studying the range of movement of contaminants in the soil. This work aims to study the effect of some variables on the rang of contaminant movement in the saturated/unsaturated soils such as: soil type, contaminant type and concentration as well as the hydraulic condition of soil. Finite element GEO-SLOPE software was used in the analysis. Three soil types (CH,CL,SM) was considered as a waste disposal location. Analysis also was applied for the selected site of a landfill located in the Mosul city. The results show that the soil condition has a clear effect on the range of contaminated transmission through soil. It was also observed that the concentration of contaminants through a higher permeability soil is greater especially in the side of the landfill. Keywords: Contaminant, finite element, unsaturated soil, diffusion, GEO-SLOPE.
Abstract: In this research, the standard precipitation index (SPI) was used to analyze rainfall records between 1941 - 2002 for nine metrological stations in the north of Iraq. In addition, digital maps of average drought magnitude and average drought intensity for the study region had drawn by using geographic information system (GIS). It is concluded that 56% of the study period were drought years.
Abstract: An attempt is made to study the effect of camber on compression zone of reinforced concrete section at mid-span of a beam. This is done by deriving formulas (based on strain measurements) to calculate total compressive axial force and axial compressive stress acting on a concrete section of single and triple span portal frames with straight and cambered beams. Keywords: Camber, Strain, Stress, Total compressive axial force
Abstract: Abstract The research handles creation as a personal ability focusing on the study of creative fluency as the most important ability in creation and in the creative architectural practice. Fluency which originally consists of many types depends only on velocity and easiness of creating ideas and alternatives without considering their originality. The problem of the research is represented in questioning the effect of the personal aptitude on the range of the creative fluency. The case study of problem was examined on the students and graduates of the Department of Architecture in Mosul University. The aim of the research is trying to find out the nature of this effect. Hence, finding the way of future predication of the extent of the ability of creative fluency of the applicants to study architecture in the Iraqi academic establishments. The research adopts and design an experiment to clarify the possibility of the existence of a quantitative index of the creative fluency depending on testing of completing architectural forms. The research finds out that architects of motional personality are more fluency of those of rational personality. It also finds out that increasing the skill of freehand drawing and the experience as well as motivation will greatly contribute in increasing their creative fluency. Keyword: Creation, Fluency, Personal Aptitude, Measure of personality, Exam of creation.
Abstract: Abstract The homes of the Prophet () are innovation of Islamic architectural in home design in the (mental and physical) sides. Research aims to find a scenario for the homes of the Prophet (), their components and their properties. The development of the Prophet's House concept represents the reference and the original and the example in the construction of housing. Return of the image of the house is evoke for the Sunni of, the Prophet Muhammad and here lies the importance of the research. Research has been divided into three parts, the first study the historical literature that described the homes of the Prophet () and their components and characteristics. The second clarify the modern scenarios of the Prophet houses design().Then offering the derived components and characteristics of the homes and discuss the scenarios according to the literatures . then in the third topic offering a new scenario as described in historical literatures (closer to the real). the research in sure the importance of studying the Sunni of the Prophet () in the design of his homes, which stabilize the morals and spirituals constructive of the house design standards and concepts. To promote Central Islamic housing (not forsake nor excessive) Key word: Islamic Architectural- The Prophet's Houses
Abstract: Abstract Interpersonal control mechanization as concept is a proposition presented clearly in the architectural thoughts in the second half of 20th century. The environment, human and build variables of university buildings is one of the important physical environments, which integrate and combine multifunction of human behavior, student control mechanize determined by interpersonal change of surrounding social/physical environment, This article represents the effects of environment, human and build variables which interface students personal differences, by testing three types of educational halls in six departments in College of Administration and Economic in Mosul University As A model, the result indicates the manipulation of physical environment to get accepted level of student interpersonal control mechanization doesn't work without study human interaction between student's together, educational staff where those have affects in student assessment of interpersonal control mechanization level. Key words: Interpersonal Control Mechanization, University buildings, Mosul University, Environment, Human,Building.
Abstract: Abstract The study deals with architecture and plant relations, aims to help the landscape designers to achieve integration between architecture and planting design of surrounding landscapes in accordance to the designer desire. The study also deals with employing planting design in changing architectural perception through changing its dimensions to be more horizontal or vertical and changing depth perception to be more closer or far from the viewer. The study aims at adopting a theoretical framework for the illusion phenomena to be employed in planting design in order to change architectural perception. This is done through using physiological phenomena related to eye and optical deviations in addition to using gestalt theory laws represented by proximity, continuity and direction , illusion properties for monocular and binocular clues, light and color formation clues, texture pattern formation and perspective clues. Keywords : architecture , plant ,landscape , perception , illusions