A mathematical model is developed to express stress-strain relationship of normal-strength concrete confined by transverse reinforcement. The sectional ductility analysis on rectangular reinforced concrete columns is performed under axial load. Analytical modals available in the literatures for confinement concrete by different types of transverse reinforcement are used. A parametric study is performed to study the influence of these parameters on the curvature ductility of reinforced concrete columns. The main parameters introduced are the amount of longitudinal reinforcement, amount of transverse reinforcement, tie spacing and the level of the compression axial force. The experimental and analytical results available in the literatures

This paper presents the results of experimental investigations to predict the bearing capacity of square footing on geogrid-reinforced loose sand by performing model tests. The effects of several parameters were studied in order to study the general behavior of improving the soil by using the geogrid. These parameters include the eccentricity value, depth of first layer of reinforcement, and vertical spacing of reinforcement layers. The results of the experimental work indicated that there was an optimum reinforcement embedment depth at which the bearing capacity was the highest when single-layer reinforcement was used. The increase of (z/B) (vertical spacing of reinforcement layer/width of footing) above 1.5 has no effect on the relativ

The main objective of this study is to develop predictive models using SPSS software (version 18) for Marshall Test results of asphalt mixtures compacted by Hammer, Gyratory, and Roller compaction. Bulk density of (2.351) gm/cc, at OAC of (4.7) % was obtained as a benchmark after using Marshall Compactor as laboratory compactive effort with 75-blows. Same density was achieved by Roller and Gyratory Compactors using its mix designed methods.

A total of (75) specimens, for Marshall, Gyratory, and Roller Compactors have been prepared, based on OAC of (4.7) % with an additional asphalt contents of more and less than (0.5) % from the optimum value. All specimens have been subjected to Marshall Test. Mathematical model

L1 adaptive controller has proven to provide fast adaptation with guaranteed transients in a large variety of systems. It is commonly used for controlling systems with uncertain time-varying unknown parameters. The effectiveness of  L1 adaptive controller for position control of single axis has been examined and compared with Model Reference Adaptive Controller (MRAC). The Linear servo motor is one of the main constituting elements of the x-y table which is mostly used in automation application. It is characterized by time-varying friction and disturbance.

    The tracking and steady state performances of both controllers have been assessed fo

The aim of this paper is to design a PID controller based on an on-line tuning bat optimization algorithm for the step-down DC/DC buck converter system which is used in the battery operation of the mobile applications. In this paper, the bat optimization algorithm has been utilized to obtain the optimal parameters of the PID controller as a simple and fast on-line tuning technique to get the best control action for the system. The simulation results using (Matlab Package) show the robustness and the effectiveness of the proposed control system in terms of obtaining a suitable voltage control action as a smooth and unsaturated state of the buck converter input voltage of ( ) volt that will stabilize the buck converter sys

This study aimed to investigate the feasibility of treatment actual potato chips processing wastewater in a continuously operated dual chambers microbial fuel cell (MFC) inoculated with anaerobic sludge. The results demonstrated significant removal of COD and suspended solids of more than 99% associated with relatively high generation of current and power densities of 612.5 mW/m³ and 1750 mA/m³, respectively at 100 Ω external resistance.

High population density, land exploitation, and water scarcity are the biggest problems in the world. To solve these problems, floating solar power plants were chosen because of the advantages of this system and high efficiency compared to land systems. In this study, the reservoirs of the five main dams in Iraq were chosen: Dukan, Darbandikhan, Hamrin, Haditha, and Mosul. They were covered with percentages of 5%, 10%, 25%, 50%, 75% and 100%. This study aimed to produce energy and meet the population's electricity needs and evaporation losses. The results revealed that covering the reservoirs by 100% can produce 230.53, 7526666, 15561, 244059, and 184692 MW from reservoirs of Dukan, Darbandikhan, Hemrin, Haditha, and  M

In this research dissimilar welds were made of low carbon steel (A516) and austenitic stainless
steel (316L) by shielded metal arc welding (SMAW) and with different electrodes (E7018) , (E6013) ,
(E309L) and (E308L). The sheet thickness (6 mm), welding current (120 A), voltage (78V), polarity
(DCRP) and electrode diameter (3.25 mm) were remained constant. Many tests were carried out,
mechanical tests included tensile test, bending and microhardness also made , and metallurgical
inspections included microstructure, delta- ferrite phase and x- ray diffraction analysis. It was found
from tensile and bending tests results that the electrode (E309L) was the most convenient for
dissimilar welds of base metal (C.St.

The best source of oil properties data is the laboratory PVT analysis of a reservoir fluid sample. However, in the absence of experimentally measured properties of reservoir fluids, these physical properties must be estimated from correlations. This paper employs more than thirty PVT reports that have been taken from different Iraqi fields. These reports contain about four hundred experimental points.
The paper suggests new correlation to calculate oil formation volume factor at and below bubble point pressure. All of the previous correlations did not take the pressure as a factor or independent variable because they calculate the oil formation volume factor at bubble point pressure only. The new correlation introduce the pressure whi

Research covers the uses the method of Quality Rating Evaluation to evaluate the
quality of production through which a determination of product quality of its production in
order to determine the amount of sales hence the profits for the company. The most important
function is to satisfy consumer at reasonable prices. Methods were applied to the product
(toothpaste) in the General Company for Vegetable Oil – Almaamoon Factory .
The company's has obtained ISO-certified (ISO 9001-2008). Random samples of
final product intended for sale were collected from the store during months (February, April ,
June , October and December) for the year 2011 to determine the "quality rating " through
the applicat

This work is aiming to study and compare the removal of lead (II) from simulated wastewater by activated carbon and bentonite as adsorbents with particle size of 0.32-0.5 mm. A mathematical model was applied to describe the mass transfer kinetic.

The batch experiments were carried out to determine the adsorption isotherm constants for each adsorbent, and five isotherm models were tested to choose the best fit model for the experimental data. The pore, surface diffusion coefficients and mass transfer coefficient were found by fitting the experimental data to a theoretical model. Partial differential equations were used to describe the adsorption in the bulk and solid phases. These equations were simplified and the

The construction sector consumes large amounts of energy during the lifetime of a building. This consumption starts with manufacturing and transferring building materials to the sites and demolishing this building after a long time of occupying it. The topic of energy conservation and finding the solution inside the building spaces become an important and urgent necessity. It is known that the roof is exposed to a high amount of thermal loads compared to other elements in a building envelope, so this needs some solutions and treatments to control the flow of the heat through them. These solutions and treatments may be achieved by using nanomaterials. Recently, nanomaterials have high properties, so that this made them go

In the construction of buildings usually, problems occur because of the causes of change orders. The main causer of change orders is the owners, consultants, and contractors. These changes lead to conflicts among them which result in influencing building projects. Therefore, it is necessary to analyze the causes of change orders to reduce them and facilitate management. This paper determines the most critical factors that cause change orders from a different point of view, a consulting owner and a contractor, and a study of the reality of the management of change orders when constructing public buildings. The method employed in this research is a field survey using interviews with experts working in the construction of p

The research aims to use a new technology for industrial water concentrating that contains poisonous metals and recovery quantities from pure water. Therefore, the technology investigated is the forward osmosis process (FO). It is a new process that use membranes available commercial and this process distinguishes by its low cost compared to other process. Sodium chloride (NaCl) was used as draw solution to extract water from poisonous metals solution. The driving force in the FO process is provided by a different in osmotic pressure (concentration) across the membrane between the draw and poisonous metals solution sides. Experimental work was divided into three parts. The first part includes operating the forward osmosis process using T

Permanent deformations (rutting) of asphalt pavements which appear in many roads in Iraq.
have caused a major impact on pavement performance by reducing the useful service life of
pavement and creating services hazards for highway users. Therefore, it is important to analyze and
investigate this type of distress.
The objectives of the present paper include; the analysis of the main contributory factors
influencing rutting, and development of statistical model for the prediction of permanent
deformation in paving materials. To achieved these objectives for the requirements of data collection. five types of gradation. (40-50) asphalt cement and different types of filler are used to prepare three hundred sixty asphalt conc

The present work investigates the effect of some of the variables in spot tungsten inert gas shielded
welding (TIG Spot) for (Aluminum-Magnesium) alloy type(5052-O) which is non–heat treatable
alloy for its wide industrial uses and applications in field of welding technology.
TIG Spot welding was performed by using tungsten electrode (EWTh2)of diameter (3.2mm) and
DC current with direct polarity (DCSP) at constant shielded gas flow rate (15litre/min).
The welded specimens were tested by using the Instron machine to determine the maximum shear
force (shear strength ) of spot welded and to define the optimum conditions of spot welding
variables in relation to the weld current, weld time and arc length of welding to

     In the present work effect of recycled heating and cooling on the values of concrete compressive strength due to high temperature of 400⁰C was studied.

    The tests show that the percent of reduction in compressive strength of the samples which exposed to a temperature of 400⁰C for one cycle was 32.5%, while the reduction was 52.7% for the samples which were exposed to recycled heating and cooling of ten times .      

   Moreover a study of the effect of specimen sizes on the percentages of compressive strength reduction due to high temperature

Institutions and companies are looking to reduce spending on buildings and services according to scientific methods, provided they reach the same purpose but at a lower cost. On this basis, this paper proposes a model to measure and reduce maintenance costs in one of the public sector institutions in Iraq by using performance indicators that fit the nature of the work of this institution and the available data. The paper relied on studying the nature of the institution’s work in the maintenance field and looking at the type of data available to know the type and number of appropriate indicators to create the model. Maintenance data were collected for the previous six years by reviewing the maintenance and financial dep

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

Several industrial wastewater streams may contain heavy metal ions, which must be effectively removal
before the discharge or reuse of treated waters could take place. In this paper, the removal of copper( II)
by foam flotation from dilute aqueous solutions was investigated at laboratory scale. The effects of
various parameters such as pH, collector and frother concentrations, initial copper concentration, air flow
rate, hole diameter of the gas distributor, and NaCl addition were tested in a bubble column of 6 cm inside
diameter and 120 cm height. Sodium dodecylsulfate (SDS) and Hexadecyl trimethyl ammonium bromide
(HTAB) were used as anionic and cationic surfactant, respectively. Ethanol was used as frothers and the

This research was conducted to study the feasibility of using fruit peels as biosorbent for removal of Pb⁺², Cu⁺² and Zn⁺² ions from simulated wastewater. A waste biomass of Pomegranate Peel or Punicagranatum L. (P. granatum L.) was chosen as neutral biosorbent in this study.Fourier transformation infrared (FTIR) was used to characterize the surface of PGP, the results confirm that amino, carboxylic, hydroxyl and carbonyl group on the surface of PGP. Different parameters such as initial concentration range between (25-200) mg/L, pH (3-7), contact time (1-2) hour, amount of sorbent (0.1- 4) gm, agitation speed range (200- 500) rpm and temperature (25- 50^oC), influencing the sorp

Experimental measurements of viscosity and thermal conductivity of single layer of graphene . based DI-water nanofluid are performed as a function of  concentrations (0.1-1wt%) and temperatures between (5 to 35ºC). The result reveals that the thermal conductivity of GNPs nanofluids was increased with increasing the nanoparticle weight fraction concentration and temperature, while the maximum enhancement was about 22% for concentration of 1 wt.% at
35ºC. These experimental results were compared with some theoretical models and a good agreement between Nan’s model and the experimental results was observed. The viscosity of the graphene nanofluid displays Newtonian and Non-Newtonian behaviors with respect to nanoparticles concen

Partial shading is one of the problems that affects the power production and the efficiency of photovoltaic module. A series of experimental work have been done of partial shading of   monocrystalline PV module; 50W, I_sc: 3.1A, V_oc: 22V with 36 cells in series is achieved. Non-linear power output responses of the module are observed by applying various cases of partial shading (vertical and horizontal shading of solar cells in the module). Shading a single cell (corner cell) has the greatest impact on output energy. Horizontal shading or vertical shading reduced the power from 41W to 18W at constant solar radiation 1000W/m² and steady state condition. Vertical blocking a column

لا يخفى دور التكنولوجيا في تصميم محطات المطارات الحديثة والمعاصرة منها، فقد شهد النصف الثاني للقرن العشرين عددا
غير قليل من المطارات تمثل فيها التكنولوجيا استعارة مجازية لثقافة العصر تؤثر على آلية التفكير والتصميم والانتاج معا. يهدف
البحث الى تحديد وتمييز هذه التوجهات وطبيعة تطبيقاتها في محطات المطارات المعاصرة .
حيث لم يعد تصميم محطات المطارات_ والتي تعد احدى اهم انواع الابنية المتخصصة_ يعتمد على اف

In this paper an atmometer apparatus were used in the greenhouses for estimating reference evapotranspiration values. Experimental work was conducted in the agriculture research center in the College of Agriculture-University of Baghdad west of the city of Baghdad. One atmometer was used in eggplant greenhouse and in cucumber greenhouse through the winter growing season 2013-2014. FAO Penman-Monteith equation was applied outside the greenhouse and used only 65% from the value of ET_o in the greenhouses for estimating the reference evapotranspiration in the greenhouse. Moreover, Penman-Monteith equation was applied in greenhouses for the evaluating the performance of the atmometer. The results show that the erro

Housing planning is one of the most important subjects in the housing sector studies. It
is wide and has many branches . .
Housing planning according to the cost and social benefit is the solution to prevent the
escalating rise in Housing shortage .
This fact is combined with which is estimated at more than three million housing unit .
And big a reduction in housing construction rate , which lead to increase the housing problem
in the country. This matter needs a clear policy from the authorities to accelerate the planning
process and to adopt that strategy to solve the housing problem in Iraq.
This strategy should adopt the principal of constructing low – cost housing complexes
through the

Reducing global warming potential (GWP) of refrigerants is needed to the decrease of ozone-depleting of refrigeration systems leakages. Refrigerant R1234yf is now used to substitute R134a inside mobile air conditioning systems. Thermodynamic properties of R1234yf are similar to R134a. Also, it has a very low GWP of 4, compared to 1430 for R134a, making it a proper choice for future automobile refrigerants. The purpose of this research is to represent the main operating and performance differences between R1234yf and R134a. Experimental analysis was carried out on the automotive air conditioning system (AACS) with 3 kW nominal capacity, to test and compare the performance of R134a with R1234yf. Experiments were accomplish

There are numerous real-world applications for delay differential equations, including engineering model systems with time delays, such as control systems and communication networks, time-limited meals, blood pressure, hemopoiesis, and others, especially when the oscillation in these equations is exploited. To fulfill the goal of this study, certain of the coefficients in the first-order logistic equation must be piecewise continuous. This can only be accomplished by using the delay differential equations with the piecewise constant argument to investigate the oscillation or nonoscillation property of all first-order logistic equation solutions. The solution's piecewise constant is the largest integer fu

Metal foam has recently been used in many engineering applications, such as solar collectors, heat exchangers, and cooling of electronic devices, which calls for studying different cases of using metal foam in these applications. The current study conducts a numerical analysis of heat transfer and fluid flow characteristics for air in a rectangular channel filled with high-porosity copper foam. The study examined the thermal performance for two cases of gradient pore density, which are arranged as (10-20-40) PPI and (40-20-10) PPI. These cases were compared with two other cases for constant pore density, 10 and 40 PPI, and empty cases. The ANSYS FLUENT 20.0 employed the Darcy-Forchheimer extended Brickman model in the tw

The purpose of this article was to identify and assess the importance of risk factors in the tendering phase of construction projects. The construction project cannot succeed without the identification and categorization of these risk elements. In this article, a questionnaire for likelihood and impact was designed and distributed to a panel of specialists to analyze risk factors. The risk matrix was also used to research, explore, and identify the risks that influence the tendering phase of construction projects. The probability and impact values assigned to risk are used to calculate the risk's score. A risk matrix is created by combining probability and impact criteria. To determine the main risk elements for the tend