تعتمد فرضية البحث على وجود ظاهرة عامة في إعمال المقاولات لدى المقاولين وهي
تجاوز الكلف الحقيقية المصروفة خلال مرحلة التنفيذ عن الكلف التخمينية للمقاولات الإنشائية
في مرحلة تقديم العطاء مما يسبب العجز المالي والمشاكل الاقتصادية للمقاولين.تبنى البحث
دورة حياة بناء النظام التي تمر بمراحل مختلفة هي تحديد المشكلة وتحليلها وتصميم النظام
الإداري المقترح.ولانجاز ذلك تم دراسة النظم العالمية والمحلية المع
Plastic waste materials are constantly increasing around the world as a result of the growing human consumption of these materials day by day, with no actual solutions to get rid of them without causing harm to the environment or the health of living organisms. Therefore, in this research, two types of plastic waste materials are utilized to enhance soft clay soil: polyethylene terephthalate (PET) and nylon (N), in percentages of (1, 1.5, 2, 2.5)% from dry soil weight, to enhance the clay soft soils properties, which are characterized by their excessive compressibility, low bearing capacity, and low shear strength. This study is carried out by conducting laboratory tests before and after the addition. These tests include
... Show Moreتضمن البحث إجراء دراسو شاممو لواقع حال وآفاق تطوير منتوج بالطات التسطيح الخرسانيو )الشتايكر( الشائع
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أإلستخدام وأإلنتاج في الع ارق. ت إن أغمب , إن لم يكن كل , المنتوج يفشل في تحقيق متطمبات المواصفو
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القياسية العراقيو 0016 لسنة .0877 سطوانات ومواشير ومن ثم قطع شتايكر
تم إعداد نماذج تتضمن مكعبات وا
أألساليب المتبعو محمياً ومن ثم تحمميا لمحاكاة وجرى فحصيا لمعرفة مقاومت
تعد التحولات العمرانية من القضايا المهمة التي شغلت العاملين في حقل العمارة وتصميم المدن . وان مراكز المدن المقدسة الاسلامية قد تأثرت وبشكل واضح وكبير بالتحولات الناتجة عن ازدياد الحاجات الانسانية والتقدم الحضاري والتكنولوجي ( الغير مدروس ) . وتظهر مشكلة البحث بصورة جلية في عملية التطور والتوسع للمدن المقدسة التي تمر في مرحلة صعبة بالنسبة لنسيجها التقليدي من جراء ما اصابها من تمزق في نسيجها وتحولها الى نسيج
... Show MoreThe prediction of the blood flow through an axisymmetric arterial stenosis is one of the most important aspects to be considered during the Atherosclrosis. Since the blood is specified as a non-Newtonian flow, therefore the effect of fluid types and effect of rheological properties of non-Newtonian fluid on the degree of stenosis have been studied. The motion equations are written in vorticity-stream function formulation and solved numerically. A comparison is made between a Newtonian and non-Newtonian fluid for blood flow at different velocities, viscosity and Reynolds number were solved also. It is found that the properties of blood must be at a certain range to preventing atheroscirasis
The need to exchange large amounts of real-time data is constantly increasing in wireless communication. While traditional radio transceivers are not cost-effective and their components should be integrated, software-defined radio (SDR) ones have opened up a new class of wireless technologies with high security. This study aims to design an SDR transceiver was built using one type of modulation, which is 16 QAM, and adding a security subsystem using one type of chaos map, which is a logistic map, because it is a very simple nonlinear dynamical equations that generate a random key and EXCLUSIVE OR with the originally transmitted data to protect data through the transmission. At th
... Show MoreTwo different oxidative desulfurization strategies based on oxidation/adsorption or oxidation/extraction were evaluated for the desulfurization of AL-Ahdab (AHD) sour crude oil (3.9wt% sulfur content). In the oxidation process, a homogenous oxidizing agent comprising of hydrogen peroxide and formic acid was used. Activated carbons were used as sorbent/catalyst in the oxidation/adsorption process while acetonitrile was used as an extraction solvent in the oxidation/extraction process. For the oxidation/adsorption scheme, the experimental results indicated that the oxidation desulfurization efficiency was enhanced on using activated carbon as catalyst/sorbent. The effects of the operating conditions (contact time, temperat
... Show Moreيهدف البحث الى دراسة السلوك (الأداء) الحراري للمبنى المشيد مسبقًا بعد تغطية سقفه المعرض للظروف الخارجية
.( بالمسطحات الخضراء (استخدام تراب بسمك 50 ملم لزراعة الثيل الامريكي مع الرش بالماء بمعدل 0.0004 لتر/ثانية/م ٢
3) م ، تقع في الطابق الثالث لمبنى في مدينة بغداد (خط عرض 33.2 درجة x 4.5 x لذلك تم تشييد غرفة أبعادها ( 4.5
شما ً لا) مع استخدام عازل حراري نوع الستايربور سمك 200 ملم لتغطية الجدران والأرضية من الداخل لتقليل ال
A multivariate multisite hydrological data forecasting model was derived and checked using a case study. The philosophy is to use simultaneously the cross-variable correlations, cross-site correlations and the time lag correlations. The case study is of two variables, three sites, the variables are the monthly rainfall and evaporation; the sites are Sulaimania, Dokan, and Darbandikhan.. The model form is similar to the first order auto regressive model, but in matrices form. A matrix for the different relative correlations mentioned above and another for their relative residuals were derived and used as the model parameters. A mathematical filter was used for both matrices to obtain the elements. The application of this model indicates i
... Show MoreRegistration techniques are still considered challenging tasks to remote sensing users, especially after enormous increase in the volume of remotely sensed data being acquired by an ever-growing number of earth observation sensors. This surge in use mandates the development of accurate and robust registration procedures that can handle these data with varying geometric and radiometric properties. This paper aims to develop the traditional registration scenarios to reduce discrepancies between registered datasets in two dimensions (2D) space for remote sensing images. This is achieved by designing a computer program written in Visual Basic language following two main stages: The first stage is a traditional registration p
... Show MoreAlginate from Large brown seaweeds act as natural polymer has been investigated as polymer and has been added to concrete in different percentages ( 0% , 0.5% , 1% and 1.5% ) by the cement weight and the study show the effect of using alginate biopolymer admixtures on some of the fresh properties of the concrete (slump & the density fresh) also in the hardened state ( Compressive strength , Splitting tensile strength and Flexural strength ) at 28 days. The mix proportion was (1:2.26:2.26) (cement: sand: gravel) respectively and at constant w/c equal to 0.47. The results indicate that the use of alginate as a percent of the cement weight possess a positive effect on fresh properties of co
... Show MoreGypseous soils are distributed in many regions in the world including Iraq, which cover more than (31%) of the surface area of the country. Existence of these soils, always with high gypsum content, caused difficult problems to the buildings and strategic projects due to dissolution and leaching of the gypsum caused by the action of water flow through soil mass. For the study, the gypseous soil was brought from Bahr Al-Najaf, Al-Najaf Governorate which is located in the middle of Iraq. The model pile was embedded in gypseous soil with 42% gypsum content. Compression axial model pile load tests have been carried out for model pile embedded in gypseous soil at initial degree of saturation of (7%) before and after soil satu
... Show MoreIn this paper, Response Surface Method (RSM) is utilized to carry out an investigation of the impact of input parameters: electrode type (E.T.) [Gr, Cu and CuW], pulse duration of current (Ip), pulse duration on time (Ton), and pulse duration off time (Toff) on the surface finish in EDM operation. To approximate and concentrate the suggested second- order regression model is generally accepted for Surface Roughness Ra, a Central Composite Design (CCD) is utilized for evaluating the model constant coefficients of the input parameters on Surface Roughness (Ra). Examinations were performed on AISI D2 tool steel. The important coefficients are gotten by achieving successfully an Analysis of V
... Show MoreFrequently, Load associated mode of failure (rutting and fatigue) as well as, occasionally, moisture damage in some sections poorly drained are the main failure types found in some of the newly constructed road within Baghdad as well as other cities in Iraq. The use of hydrated lime in pavement construction could be one of the possible steps taken in the direction of improving pavement performance and meeting the required standards. In this study, the mechanistic properties of asphalt concrete mixes modified with hydrated lime as a partial replacement of limestone dust mineral filler were evaluated. Seven replacement rates were used; 0,0.5, 1, 1.5, 2, 2.5 and 3 percent by weight of aggregate. Asphalt concrete mixes were prepared at their
... Show MoreAluminum-Silicon alloys, with soft lubricant metal, are considered to be one of the important tribological alloys which resist seizure. The effect of different lead percentages (1-20%Pb) that added to the modified eutectic Al-12%Si alloy on the wear rate and resistance was studied by sliding these alloys under dry sliding conditions on a carbon steel disc at different sliding distances (2.24-40.37 km). The results showed that the wear rate was decreased and wear resistance increased with increasing lead percentage of Al-12%Si alloy. Furthermore, wear rate was increased linearly with increasing sliding distance.
earthquake excitations. Above and below ground tank, uses have been considered. A linear threedimensional finite element analysis has been used to predict the natural frequencies. Analysis parameters are the ratio of height to length of the tank, the type of soil, level of water in the tank, and also the wall thickness. The results for top displacement and axial force components for a full tankabove ground case have values greater than those in half- full (31%) and empty tank cases (75%). At the opposite of that, the underground tank demonstrates that top displacement and axial force components for an empty tank case have values greater than those in half- full (19%) and full tank cases (40%). The base shear for above ground tank case ha
... Show MoreWhen designing the pavement layers, a suitable thickness must be chosen to protect the pavement from environmental conditions and traffic loads and ensure the structure's durability up to the design life. To investigate the behavior of flexible pavement, the characteristics and thickness of each layer are programmed into the finite element method (FEM). The Abaqus program is one of the infinite-element analysis programs. The use of the Abaqus program leads to a reduction in cost and time compared to laboratory tests. In this study, the Abaqus program analyzed a three-dimensional model of a multi-layered road section, and all materials have elastic behavior. The model comprises five layers (wearing, binder, base, subbase,
... Show MoreAeroelastic flutter in aircraft mechanisms is unavoidable, essentially in the wing and control surface. In this work a three degree-of-freedom aeroelastic wing section with trailing edge flap is modeled numerically and theoretically. FLUENT code based on the steady finite volume is used for the prediction of the steady aerodynamic characteristics (lift, drag, pitching moment, velocity, and pressure distribution) as well as the Duhamel formulation is used to model the aerodynamic loads theoretically. The system response (pitch, flap pitch and plunge) was determined by integration the governing equations using MATLAB with a standard Runge–Kutta algorithm in conjunction with Henon’s method. The results are compared with
... Show MoreExperimental research was carried out to investigate the performance of CFRP wrapping jackets used for retrofitting twelve square reinforced concrete (CR) column specimens damaged by exposure to fire flame, at different temperatures of 300, 500 and 700ºC, except for two specimens that were not burned. The specimens were then loaded axially till failure after gradual or sudden cooling. The specimens were divided into two groups containing two main reinforcement ratios, ρ= 0.0314 and ρ= 0.0542. This was followed by the retrofitting procedure that included wrapping all the specimens with two layers of CFRP fabric sheets. The test results of the retrofitted specimens showed that the fire damaged RC
... Show MoreIn this paper, a proposed method based on real-coded genetic algorithm is presented and applied to solve multiple load flow solution problem. Genetic algorithm is a kind of stochastic search algorithm based on the mechanics of natural selection and natural genetics. They combine the concepts of survival of the fittest with genetic operators such as selection, crossover and mutation abstracted from nature to form a surprisingly robust mechanism that has been successfully applied to solve a variety of search and optimization problems. Elitist method is also used in this research, and blending models are implemented for crossover operator. In the proposed work, five busbars typical test system and 362-bus Iraqi National Grid are used to dem
... Show MoreBubbled slabs can be exposed to damage or deterioration during its life. Therefore, the solution for strengthening must be provided. For the simulation of this case, the analysis of finite elements was carried out using ABAQUS 2017 software on six simply supported specimens, during which five are voided with 88 bubbles, and the other is solid. The slab specimens with symmetric boundary conditions were of dimensions 3200/570/150 mm. The solid slab and one bubbled slab are deemed references. Each of the other slabs was exposed to; (1) service charge, then unloaded (2) external prestressing and (3) loading to collapse under two line load. The external strengthening was applied using prestressed wire with four approaches, wh
... Show MoreThe corrosion protection of low carbon steel in 2.5 M HCl solution by kiwi juice was studied at different temperatures and immersion times by weight loss technique. To study the determination of the optimum conditions from statistical design in evaluation of a corrosion inhibitor, three variables, were considered as the most dominant variables. These variables are: temperature, inhibitor concentration (extracted kiwi juice) and immersion time at static conditions.
These three variables are manipulated through the experimental work using central composite rotatable Box – Wilson Experimental Design (BWED) where second order polynomial model was proposed to correlate the studied variables with the corrosion rate o
... Show MoreThis paper describes the geotechnical properties of Al-Ammarah soil of Ammarah city in Messan Governorate-southern parts of Iraq. Data and other information taken from numbers of geotechnical reports that performed under the supervision of Consulting Engineering Bureau of Baghdad University. This research is devoted to study the correlation between different physical properties such as (LL, PI, LI, W., C.) with different mechanical properties such as (qu, Ces C SPT). The correlation is verified using simple regression analysis. From the regression results it was found that there is direct correlation between different parameters. By using the correlation-with some information- preliminary investigation stages and studies of any structure
... Show Moreأصبحت الاستدامة في الدراسات والبحوث الحديثة العنصر الأهم و الجزء المركزي الذي يجب أن يؤخذ بالحسبان في
التصميم و التخطيط الحضري للمدن . في حين نجد قصورًا في التغطية المعرفية لأهمية المنظومة الاجتماعية للاستدامة في
البنية الحضرية وآليات تحقيقها في البنية الحضرية المعاصرة.
لذا يهدف البحث الى ( الكشف عن مقومات الاستدامة الاجتماعية في البنية الحضرية التقليدية، وإستقراء آليات تحقيقها في
البنية الحضرية ا
In this paper, an Anti-Disturbance Compensator is suggested for the stabilization of a 6-DoF quadrotor Unmanned Aerial vehicle (UAV) system, namely, the Improved Active Disturbance Rejection Control (IADRC). The proposed Control Scheme rejects the disturbances subjected to this system and eliminates the effect of the uncertainties that the quadrotor system exhibits. The complete nonlinear mathematical model of the 6-DoF quadrotor UAV system has been used to design the four ADRCs units for the attitude and altitude stabilization. Stability analysis has been demonstrated for the Linear Extended State Observer (LESO) of each IADRC unit and the overall closed-loop system using Hurwitz stability criterion. A minimization to a
... Show MoreAccurate prediction of electromagnetic moments in odd-A nuclei near doubly magic cores is challenging due to their sensitivity to core polarization and single-particle structure. This study investigates the predictive performance of Skyrme-HFB (SLy4) against shell model (SM) calculations for quadrupole moment (Q20) and magnetic dipole (M10) in the selected nuclei (17O, 17F, 39Ca, 39K, 47Ca, 49Sc, 131In, 133Sb, 133Sn, and 209Bi) near doubly magic cores using the Hartree-Fock-Bogoliubov (HFB) method and the SM method. The SLy4 interaction was used in HFB calculations. On the other hand, SM cal
... Show MoreThe construction industry is a major contributor to resource depletion, environmental degradation, waste production, and greenhouse emissions, which makes it necessary to adopt alternative development models. The Circular Economy (CE) has become one of the potential strategies of resource conservation, waste reduction, and environmental equilibrium restoration. This paper aims to provide a systematic literature review of the CE principles by analyzing research papers and articles in scientific journals and some university theses, encompassing the R-Principles (Reduce, Recycle, Reuse, Refuse, Rethink, Repair, Repurpose, Remanufacture, And Recovery), together with principles related to design and production, use and consum
... Show MoreThis study intends to evaluate the accuracy and reliability of satellite data from the NASA POWER project in capturing important climatic variables, which are precipitation and air temperature, compared with data collected from the National Climate Data Center (NCDC) ground-based weather stations located in the Khassa Chai River basin. The basin has a topographic gradient beginning on the northeastern highlands and sloping towards the southwest. The Khassa Chai River Basin experiences a semi-arid climate, with hot, dry summers and relatively cold and wet winters. Daily precipitation and temperature records (2010–2024) were collected from four weather stations, in addition to records from the NASA POWER recording at the
... Show MoreThe impact resistance of bimetallic materials is a critical aspect of engineering, particularly in the aerospace and automotive industries. Notched geometries are often encountered in real-world scenarios due to manufacturing defects or intentional design features. The present work investigates the impact resistance and fracture behavior of Al/Cu bimetallic sheets, focusing on the influence of notches on fracture energy, the fracture process zone, and overall failure mechanisms. For interpretation and analyses purposes, the impact test results were integrated with SEM fractographic analysis and the Essential Work of Fracture (EWF) framework. Four notch dimensions of U and V geometries were tested. Experimental results in
... Show Moreموخرا اكتسبت نماذج التكامل المتعلقة بتخطيط الإنتاج الكلي ومشاكل جدولة التحكم أهمية متزايدة وكذلك المزيد من الاهتمام في بيئة أنظمة التصنيع المعقدة والمتغيرة باستمرار. يأتي تعقيدها من اثر التعامل مع قيود القدرة والطلبات المتقلبة، وهذا التكامل يعزز الكفاءة، ولكنه يفرض تحديات حسابية ونمذجة كبيرة. وبالتالي، تقدم هذه الورقة نموذجًا متكاملًا جديدًا لتخطيط الإنتاج الكلي ومشكلة جدولة الآلة الواحدة التي تقلل من
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