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Engineering and Technology Journal

مجلة الهندسة والتكنولوجيا

ISSN: 16816900 24120758
Publisher: University of Technology
Faculty: Presidency of the university or centers
Language: Arabic and English

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جمهورية العراق –بغداد
الجامعة التكنولوجية- مجلة الهندسة والتكنولوجيا- ص.ب. 35010
Email: etj@uotechnology.edu.iq
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Table of content: 2016 volume:34 issue:6 Part (A) Engineering

Article
Adaptive Reuse in Valuable Building Through The Adoption of Change in the Circulation Configuration
التكيف بإعادة الاستخدام في الابنية ذات القيمة باعتماد التغيير في منظومة الحركة

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Abstract

The concept of adaptation gained a considerable attention since the sixties of the last century as one of the basic concepts related to architecture .Many studies dealt with it in different aspects some were related to form transformations within design process, others were with transformation and flexibility or with the reuse , and despite the understanding for the adaptation as a concept in previous studies , but it was characterized by concise when related to , the re- use , especially in valuable building, that’s why the need for the scientific specialized studies for that concept and its role in the valuable buildings emerged , and thus we articulated the research problem and defined it as ( the lack of clarity of the adaptive reuse in general and its role in valuable building in specific) . The research goals were defined by (determining the characteristics and procedures of the concept of adaptive reuse and determining the possible formulas and methods to re- use valuable buildings). The theoretical framework was structured accordingly in two axes, first: to define the concept of valuable building and its theoretical framework, second: to determine the operation definition of adaptive reuse, and identify the most important variables in the process of adaptive reuse, then addressed the method of measurement and data analysis, then identify samples for the case-study, which was elected by one category dispersed among local and non-local models. The final stage was to analyze and discuss the results and determine the final conclusions finally, research has come to a number of recommendations and future prospects for research.حظي مفهوم التكيف بالكثير من الاهتمام منذ ستينات القرن الماضي كأحد المفاهيم الأساسية المرتبطة بالعمارة إذ تناولت الكثير من الطروحات المفهوم من نواحي مختلفة منها ماأرتبط بالتحولات النمطية والتحولات الشكلية ضمن العملية التصميمية ومنها ماأرتبط بمفهوم التحويل والمرونة او بإعادةالأستخدام, وبالرغم من الطرح الواسع لابعاد مفهوم التكيف في المعرفة السابقة الاّ إنه أتّسم بالإقتضاب بما يتعلق بإعادةالأستخدام وخاصة في الأبنية ذات القيمة لذا برزت أهمية الحاجة العلمية لدراسة متخصصة حول هذا المفهوم ودوره في الأبنية ذات القيمة , وبذلك تحددت مشكلة البحث (عدم وضوح مفهوم التكيف بإعادة الأستخدام بشكل عام ودوره في الأبنية ذات القيمة بشكل خاص من خلال التغيير في منظومة الحركة) وتحددت اهدافه بـ (تحديد خصائص واجراءات مفهوم التكيف بإعادة الأستخدام من خلال التغيير في منظومة الحركة و تحديد صيغ واساليب ممكنة لإعادة أستخدام الأبنية ذات القيمة ), ولتحقيق هدف البحث تطلب اولا بناء الاطار النظري الشمولي ضمن المحور الاول بتحديد كلا من مفهومي : التكيف انواعه ومستوياته , ومفهوم المباني ذات القيمة ), فيما تناول المحور الثاني تحديد مفهوم التكييف بإعادة الاستخدام والتركيز على مفهوم " التغيير في منظومة الحركة " كمتغير اساسي في عملية التكيف بإعادة الأستخدام وتناول المحور الثالث الدراسة العملية من خلال تحديد طريقة القياس وتحليل البيانات , ثم تحديد العينات للتطبيق العملي والتي تم انتخابها من فئة واحدة (سكن) لنماذج محلية. أما المرحلة الاخيرة فأختصت بتحليل مناقشة النتائج وتحديد الإستنتاجات النهائية والتوصل الى عدد من التوصيات والآفاق المستقبلية.


Article
Strength Evaluation of CO2-Cured Cellulose Date Palm Fiber Reinforced Cementitious Boards

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Abstract

In recent years there has been an increasing demand to recycle wastes produced by the agricultural and industrial processing. The aim of this paper is to investigate the suitability of date palm (Phoenix dactylifera) as lignocellulosic materials for the production of wood-cement composite boards, in addition to enhance their compatibility with cement using physical pretreatment processes and accelerated carbonation curing. Experiments were performed to assess the physical properties (as density, flexural strength, toughness and E-modulus), and micro structural properties (as determined by scanning electron microscopy) of the produced cement boards. The results show an improvement in the physical and microstructural properties of cellulosic fiber-cement composites by using accelerated CO2 curing method. In addition, excessive carbonation rate associated with pure gas carbonation does not necessarily lead to high strength and even detrimental strength development was found, which was shown by cement paste.


Article
Sand Column Stabilized by Silica Fume Embedded in Soft Soil

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Abstract

This research aims to study the behavior of the sand columns stabilized with silica fume (as an additive with different percentages) and driven in soft soil bed with undrained shear strength (cu) between 16 – 21 kPa. Holesin the shape of columns with diameter 50 mm and length 300 mm have been drilled in a soil bed and backfilled with sand mixed with several proportions of silica fume with 7-days curing. A rigid circular footing with diameter 64.6 mm was located on each column and loaded axially till failure. The results analysis of the model tests indicated an encouraging improvement in load carrying capacity of the columns and considerable reduction in the settlement compared to the conventional stone columns. The bearing improvement ratio and settlement reduction ratio exhibited by the sand columns are 1.18 and 0.71, respectively. The best possible addition of silica fume content in sand–silica fume columns is 7% giving bearing improvement ratio and settlement reduction ratio of 1.56 and 0.5 respectively.


Article
NLMS Adaptive Filter Algorithm Method for GPS Data Prediction

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Abstract

This paper proposes a method for the predictionofGPS data using Normalized Least-Mean-Square Algorithm (nlms) was used as application of adaptive filter.Fourdifferent scenarios were taken to predict the GPS data.Thefirst one was without blocking of data and the three others with blocking for (3, 6, and10 seconds,respectively), with implementation in MATLAB. The prediction process of the GPS receivers is required for different reasons, such as maneuvering, founding obstacles, and also the time of booting may be too long due to the difficulty inobtaining the satellite’s position,hencein such casesone can use the GPS prediction data in order to solve these problemsand reduce the booting time and avoid losing of the GPSdata for any reason.

Keywords

NLMS --- GPSdata --- prediction --- adaptive filter --- blocking


Article
Modelling of Carburization Parameters Process for Low Carbon Steel

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Abstract

This paper representsthe carburization parameters for steel (1020) using Desirability Function Analysis-DFA. The experiments were conducted using Taguchi (L9) orthogonal array. Carburization parameters such as carburization temperature, carburization time and tempering temperature were optimized by multi - response considerations depending onmicrohardnessand were rate measurements. The optimal carburizing parameters had been determined by composite desirability value obtained from desirability function analysis while significant contribution of parameter was determined by analysis of variance (ANOVA). The analyses results showed that optimal combination for higher hardness and lower wear rate were at (A2=920 oC, B2= 3 hours and C3=120 oC). Confirmation test was also conducted to validate the test results. Mathematical models for composite desirability, microhardness and rate wear were determined. Experimental results showed that the carburization performance can be improved effectively through desirability approach.


Article
Tensile Properties Distribution of Coir Natural Fiber Using Weibull Statistics

Authors: Ahmed Mudhafar Hashim --- Jawad Kadhim Oleiwi
Pages: 1080-1087
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Abstract

In current time, most of the composites based on polymer resins reinforced with natural fibers than synthetic fibers for environmentally friendly consideration. This work investigate the study of tensile properties distribution of coir natural fiber by using Weibull statistics to quantify the degree of variability in fiber strength. Single-fiber tensile and microscopy tests were performed to determination the tensile properties (tensile strength and modulus of elasticity) and fiber crosssectional area respectively. The experimental results showed that the coir natural fiber have a good tensile strength and modulus of elasticity of 89.91–237.46 MPa and 2.55-8.78 GPa respectively. The Weibull distribution indicates that the coir natural fiber have a high degree of linearity of R2 = 0.942. The Weibull modulus for corn fibers was β = 3.650 , gives a good variability in tensile strength.


Article
Harmonic Analysis of a Power Distribution Network in Baghdad City

Authors: Thamir M. Abdul-Wahhab
Pages: 1088-1103
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Abstract

In electrical distribution systems, capacitors are used for reactive power compensation and reducing active power losses. With the presence of harmonic distortion the installation of shunt capacitors will amplify the harmonics distortion level. The objective of this study is to investigate the effect of capacitor placement on a certain feeder in AL_AMILdistribution network in Baghdad city with the presence of harmonics generated by a large non-linear load such as an ARC furnace. The CYMDIST software package was used for the implementation of this study. The results show the effectiveness of optimal capacitor placement on reactive power compensation, enhancing voltage profile, relieving the lines from over load conditions, and reducing active power losses. However the total harmonic distortion level is increased and methods are required for mitigation the harmonic effects. Several passive filters have been considered to tune out the harmonics; among these the double tuned filter has proven to be the most effective one for our particular case.


Article
Burr Formation Mechanisms During Drilling Operations Of Low Carbon And Stainless Steels

Authors: Samir Ali Amin Alrabii
Pages: 1104-1115
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Abstract

In drilling operations, burrs cause many problems for product quality and functionality. Therefore, understanding of burr formation mechanism is essential in order to reduce the deburring cost by reducing burr formation. Also, to avoid or minimize the burr formation during drilling, it is necessary to realize the relationship between the burr formation mechanism and the cutting parameters involved in the machining operations. Therefore, this research is an attempt to investigate experimentally the influence of using a wide range of cutting speeds, feed rates, and depth of cuts on the burr formation mechanism in drilling operations of low carbon and stainless steels plates using HSS cutting tools and cutting fluids. Additionally, this study was focused on the effect of these cutting parameters on the burr size and type. Thus, the average heights of exit formed burrs were measured at different machining conditions.Two types of burr mainly formed and observed (transient and uniform burrs) during drilling both steels. Accordingly, two types of burr formation mechanism related to these observed types of burr were explained. It was found that the average burr height for both steels generally reduced with increasing cutting speedsand feeds due to the change of burr type from a transient burr at lower cutting speeds and feeds to a uniform burr with and without a drill cap at higher speeds and feeds. Finally, no crown burr type formed and observed during drilling both steels in comparison with previous works.


Article
Post Buckling Behavior of Prismatic Structural Steel Members with Semi Rigid Connections

Authors: Amer M. Ibrahim --- Murtada A. Ismael
Pages: 1116-1130
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Abstract

In most designs of steel frames,beam-column connections are assumed either perfectly pinned or fully rigid. This assumption results in an incorrect estimation of the structural behavior of these frames. Practically, beam-column connections are between these two extreme assumptions and possess some rotational stiffness; therefore, it is called semi rigid connection. This research, presents a numerical analysis using finite element method to study the effect of semi-rigid connection on post buckling behavior of prismatic structural steel frames. The beam-column connection is modeled by linear elastic rotational spring element with specified rotational stiffness. The obtained results reveal that changing beam-column connection from rigid to semi rigid with different rotational joint stiffness values make the load-displacement curve of post buckling behavior less stiffer, the ultimate load decrease and ultimate vertical displacements increase with percentages depend on joint stiffness value and type of frame ;thus, semi-rigid connection should be considered in analysis and design of steel frames which exhibits post buckling behavior to obtain more realistic results.


Article
Development of Integrated Strategy for Managing Construction Sector in Iraq Project Management Maturity Models

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Abstract

A lot of construction projects fail to complete their processes according plans, leading to financial and technical problems. The paper tries to study the extent to which the application of best management practices will have a quantitative measurable effect on project success. The researcher developed a model to assess project management maturity for a sample study of the Iraqi ministry of construction and housing and public municipalities, then applied regression analysis to find the correlation of the maturity level of the cost, time management and the average project management processes maturity level and also deviation coefficient during the year (2007-2014).


Article
Improving The Stability of GRP Routing Protocol

Authors: Turkan A. Khaleel --- Ahmed M. Fadhil --- RanaKh.Sabri
Pages: 1142-1149
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Abstract

More recent works aim at enhancing MANET performance, because of the multiple problems caused by the wireless transmission constraints. The problem that faces the routing protocol is to obtain the stable path with nodes movement. A route between a source to destination is called "stable" if it consists of mainly stable neighbors at each intermediate hops. In this paper, a Geographic Routing Protocol (GRP) algorithm was chosen as a MANET routing protocol to be modified for stability. A new protocol wasthen created called SGRP routing protocol which workslikethe GRP routing algorithm, but with some modification to obtain better link stability. The main objective of this research is to decrease the time delay caused by wireless network and enhance the network performance by selecting the best route in the set of available routes that will have the least distance and highest neighbor stability. The model for this research has been designed and simulated by using C/C++ language embedded in the OPNET Modeler 14.5 software package. The SGRP routing model has been compared with the original GRP protocol. Acceptable results have been obtained depending upon the performance of metrics (MANET delay, total packets dropped and Throughput). The average MANET Delay and total packets dropped during the use of SGRP have decreased, while the throughput was acceptable.


Article
Fire-Resistance of Styroferrocement Sandwich Panels

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This paper investigates the effect of fire on ferrocement sandwich panels. The experimental program consisted of fabricating and testing nine panels (400X400x30 mm in dimensions). The variables were type and number of mesh and Styrophoam content. A special arrangement was designed to create the effect of fire on panels. Test results showed that ferrocement panels have an endurance of fire when compared to control panels which may provide a desired protection to fire. In-spite-of wire mesh cracks, in plane cracks occurred when more volume fraction of mesh included. Whereas Styrophoam content affected the number of in-plane cracks. Plastic wire mesh had no significant effect on the wire mesh-induced cracks


Article
Protection Coordination with Distributed Generation in Electrical System of Iraqi Distribution Grid

Authors: Rashid H. Al-Rubayi --- Ammar Abbas Majeed
Pages: 1161-1181
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The nature characteristic in conventional distribution networks is radial by single source supplying a downstream network. The interest about the environmental impacts and development in technologies have led to increase distributed generation (DG) interconnected in distribution networks. Protective device coordination will be affected by adding DGs to the existing network through participating to the change in direction of power flow and fault current values and direction which cause loss in settings and mis-coordination for protective devices, especially over current relays. The effect of DG on coordination depend upon number, location and size of DG, so in this work, the Particle Swarm Optimization (PSO) technicality utilization to locate optimal location and sizeof DG to obtain minimum active power losses.The Time Current Characteristic (TCC) curves represented which depended on the over current protection relays parameters to find settings and limited any loss in it, in order to reset these relays to obtained the proper operation without intersections in time of operation and satisfy optimal coordination between primary and pack up over current protection relays. In this work two soft wares are used, the first is Matlab R2014a for implementation of the PSO algorithm while the second software is CYMDist program for load flow analysis, short circuit current calculation and protection coordination device analysis. To verify the developed algorithm parts from Iraqi distribution network (Baghdad Al-Rusafa 33KV distribution networks). So, used two DG units with total capacity 50MW distributed in 33kV of South Al-Rusafa distribution network which represented about 9.4% from the total load of this network 533.5MW, the total active power losses reduced from 11.597MW to 6.658MW with losses reduction 6.96MW about 43% from total losses.


Article
Power Saving Sleep Mode Enhancement Mobile WiMAX Networks

Authors: Ibtesam R. K. Al-Saedi --- Farah F. H. Alkhalid
Pages: 1182-1193
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Recently, the use of mobile devices to run multimedia applications is becoming more popular. Such applications are known to be energy consuming. Since these devices are mostly battery powered with a limited battery life, energy saving strategies becomes vital for such systems operation. WiMAX systems utilize a standard sleep mode in order to reduce the mobile station (MS) power usage. It is also used to reduce the usage of base station (BS) air interface resources. IEEE 802.16e proposes three power saving classes (PSCs), depending on the type of the application(s) running on the device. However, when multiple applications that belong to different service types are operating simultaneously, the power consumption may increase due to overlapping among the used PSCs. In this work, a new mechanism is proposed to minimize power consumption of mobile WiMax devices. The proposed mechanism tries to eliminate the overlapping of PSCs by synchronizing the different PSCs. A simulation study is conducted and the simulation results indicate that the proposed mechanism can significantly reduce power consumption of MS; OPNET 14.5 modeler is the simulation tools that used in this work. However, this version of OPNET does not support sleep mode, but the sleep protocol is programed (in this work) using C Language inside the modeler, in order to show the effect of the proposed mechanism to enhance the power saving.


Article
Design of Compact Dual-band Antenna for 4G LTE Wireless Devices

Authors: Ali J. Salim
Pages: 1194-1206
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In this paper, the planar dual-band monopole antenna is presented for Long Term Evolution (LTE) and Wireless Local Area Network (WLAN) applications. The design of the proposed antenna is based on Peano fractal curve and meander line structures. The antenna operates in 1.71 GHz to 2.01 GHz in the desired LTE frequency band and 5.0 GHz to 5.5GHz band (IEEE 802.11a band). The frequency band 1.71 - 2.01 GHz is already available as a study of the current plan according to UMTS and LTE systems (the band no.4). The antenna has been fixed on a substrate boardArlon with εr= 2.33 and thickness of 0.9 mm. Simulation results shows that the proposed antenna has promising radiation characteristics and a reasonable gain of 2.155 dBi at the lower band and 4.772 dBi at the upper band. The simulation and evaluation of antenna performance werecarried out using Microwave Studio Suite of Computer Simulation Technology CST.


Article
Effect of Relative Density on Behavior of Single Pile and Piles Groups Embedded with Different Lengths in Sand

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The present research investigates the effect of axial relative density on the ultimate load of model piles with different lengths driven in dry sandy soil having small scale model piles. The materials used in this study are divided into three parts they are; sandy soil, steel piles and aluminum pile caps.A total number of 27 model tests are carried out using three relative densities (33%, 60%, and 80%) corresponding to loose, medium and dense sand, respectively. A square section steel solid model piles are used with 18 mm width and (320, 420, 520) mm embedded length (Ld). A 6B distance between the piles center to center is selected to eliminate the effect of group interaction. Two pile groups' configuration (1×2) and (2 × 2) are considered in this study connected by aluminum caps with smooth surface having a thickness of 25 mm. The load applied on the models is measured by a pressure transducer connected to the main line of the hydraulic pressure system and applying up to failure. During all the experimental tests, the loading rate is kept at 3 mm/min. It was founded that relative density has more impact on (2×2) pile group than on (1×2) pile group and single pile. The average rate of increase in the ultimate load from loose to medium is about 15% greater than the average rate of increase from medium to dense. Also, the ultimate load of pile increased about 96% with changing the sand density from loose to medium sand for single and piles group while the average increment is about 81% from medium to dense. The increase in embedded length of pile caused increasing the ultimate load capacity and decreasing the settlement ratio. The average rate of increase in the ultimate load when the embeddedlength changes from 32 cm to 42 cm is about 4% less than the average rate of increase when the embedded length changes from 42 cm to 52 cm. Also, use of (1×2) piles group instead of a single pile, the average rate of increase is about 6% less than the average rate of increase when change from (1×2) group to (2×2) pile group. Finally, when the number of piles changes from single pile to (1×2) piles group, and to (2×2) piles group, the average of increase of ultimate load is about 102.5% and 108.5% respectively.


Article
Evaluation of Friction Forces in the Joints of Gough-Stewart Manipulator

Authors: Hassan M. Alwan --- Sameh Fareed Hasan
Pages: 1221-1234
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Abstract

Many of researchers neglected the effect of friction phenomena in the robotics analysis and the others investigated and studied the behavior of friction phenomena in robot joints with one type of friction. The aims of this paper is to account and investigate the friction forces in all the joints of Gough-Stewart manipulator taking into consideration two types of friction(i.e. viscous and coulomb friction) . A mathematical model is derived to evaluate the reaction forces developed in robot joints due to movement of robot. Computer codes are written using MATLAB software to solve the equations derived to simulate the friction force in the joints.


Article
Drawing of Hexagonal Shapes from Cylindrical Cups

Authors: Waleed Khalid Jawed --- Sabih Salman Dawood
Pages: 1235-1246
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Abstract

The main aim of this work is design and manufacturing cylindrical and hexagonal dies to produce hexagonal cups from transform the cylindrical cups to hexagonal cups and affect of wall corner radii of die. As well as using some parameters which effect of on the hexagonal deep drawing process, especially on the punch force, strain distribution and variation of the cup wall thickness for three stages such as (wall corner radius of die and punch speed). 3-D models of cylindrical cups of (43 mm) outer diameter, and diagonal and side distance of hexagonal cups are (41and36mm) respectively, (0.7mm) thickness made from low carbon steel (1006–AISI), has been produced. A commercially available finite element program code (ANSYS11.0), was used to perform the numerical simulation of deep drawing operation. Two types of wall corner radii of die ( =0.7, 4 mm) with constant punch profile radius equal to ( =4) mm and die profile radius equal to ( =8 mm), various drawing speeds equal to (50, 200, and 500 mm/min (were used. From the numerical and experimental results of drawing operation, it, the maximum thinning occurs at cup corner radius when used wall corner radius of die equal to ( = 0.7mm). The best strain and thickness distribution over all zones in produced cup obtained when using wall corner radius of die is equal to = 4 mm) and High drawing speed (v=500 mm/min) leads to increase drawing force and more thinning in cup corner.


Article
Influence of Risks on Project Planning Decision

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In this research, a "Project planning / Risk analysis" model that consists of four modules has been developed to aid the decision-maker in planning different types of projects and analyze the risks. These modules are: Planning, Decision-Making Process 1, Risk Analysis, and Decision-Making Process 2.The model can be used to generate different scenarios of project plan according to the decision-maker's opinion in choosing the type of probability distribution, changing the probability/impact of the risk occurrences and/or changing the input values (time/cost) into the probability distribution. These scenarios will be resulted by Monte Carlo simulation as well as the application of qualitative techniques to assess risks and combining their probability of occurrence and impact, and quantitative techniques to numerically analyze the effect of identified risks. Moreover, it gives the decision-maker the ability of avoiding unexpected events through providing a futuristic look of the most project risky activities by implementing risk ranking matrix using heat map. The developed model will go through interrelating three software; Microsoft Project, Microsoft Excel and @Risk from Palisade.


Article
Effect of Adding Used-Foundry Sand on Hot Asphalt Mixtures Performance

Authors: Hasan Hamodi Joni --- Hussein HamelZghair
Pages: 1253-1264
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Abstract

Highway material researchers have been investigating the use ofbyproduct materials such as used-foundry sand as a fine aggregate and mineral filler in asphaltic concrete mixtures to replace the traditional asphalt mixes by new one contain this type of sand. This researchshow a study using of used-foundry sand as an alternative to filler and fine aggregate in hot asphalt mixture, aims to minimize the environmental effect caused by this waste materials. To evaluate mechanical properties, the mixtures were designedby Marshall method which contain the used- foundry sand and determine indirect tensile strength ratio and then compared with hot asphalt mixtures contained of two types of filler(ordinary cement and limestone dust).The results showing that the reuse of foundry sand in the mixtures of hot mix asphalt as a partial replacement of fine aggregate that retained on sieve No 200 and a total replacement of filler material is viable and can be used in asphalt mixtures production. The hot asphalt mixtures containing of used-foundry sand with cement filler type improved the moisture sensitivity performance as characterized in indirecttensile strength ratio. Furthermore, that theresults obtained from Marshall stability test indicate maximum Marshall stability obtained for mixtures with cementand used-foundry sand more than these stabilities for mixes with used-foundry sand and lime stone dustas a filler were (15.3, 12.5 and14.1) respectively .

Table of content: volume:34 issue:6 Part (A) Engineering