A static analysis of cellular plate structures of linearly varying depth is presented by using the
simplified grillage method. The cellular plate structure in this study consists of top and bottom
flange plates (non-parallel) separated by longitudinal webs having varying depth. A variational
formulation of thin-walled beam element with linearly varying depth has been carried out for the
derivation of the stiffness matrix of the grillage members for various warping restraint effects. The
effect of warping restraint in stiffness is included by two methods, firstly; the implicit method
(through the torsional constant) and secondly; by the explicit method (as independent warping
degree of freedom). Two diff
In this paper, the transient flow in a rectangular open channel has been studied for different conditions. The velocity and depth of water have been calculated at different sections in the channel. A computer program (Channel) was developed to solve the mathematical model using characteristic method .The initial conditions have been calculated using Runge-Kutta method.
This study is concerned with the derivation of differential equation of motion for the free coupled vertical – torsional and lateral vibration of opened thin-walled curved beams. The curved beam to be considered in this study is of isotropic opened thin – walled (I) section with equal top and bottom flanges. The derivation depends on Hamilton's principle which required finding the potential and kinetic energy of the curved beam section due to internal stresses and all types of movements (Vertical,Torsional and Lateral) .The effect of restrained warping displacement is also considered in this study. Three differential equations are derived for vertical, torsional and lateral movement .and approximate solutions are developed by using t
... Show MoreIn the construction of modern buildings, a network of pipes and ducts is necessary to accommodate essential services like water supply, sewage, air-conditioning, electricity, telephone, and computer network. Passing these services vertically required creating openings in slab (Flanges of T-Beams) after or before construction.
New researches show that the concrete flanges provide a certain level of shear resistance above a certain width. Therefore, due to existing of these openings or cold joints in slab (Flange) and abrupt changes in the sectional configuration, opening corners are subject to high stress concentration that may lead to reduction in stiffness of the T-Beam and produced cracking and excessive deflection.
In the presen
Kriging, a geostatistical technique, has been used for many years to evaluate groundwater quality. The best estimation data for unsampled points were determined by using this method depending on measured variables for an area. The groundwater contaminants assessment worldwide was found through many kriging methods. The present paper shows a review of the most known methods of kriging that were used in estimating and mapping the groundwater quality. Indicator kriging, simple kriging, cokriging, ordinary kriging, disjunctive kriging and lognormal kriging are the most used techniques. In addition, the concept of the disjunctive kriging method was explained in this work to be easily understood.
The performance of sewage pumps stations affected by many factors through its work time which produce undesired transportation efficiency. This paper is focus on the use of artificial neural network and multiple linear regression (MLR) models for prediction the major sewage pump station in Baghdad city. The data used in this work were obtained from Al-Habibia sewage pump station during specified records- three years in Al-Karkh district, Baghdad. Pumping capability of the stations was recognized by considering the influent input importance of discharge, total suspended solids (TSS) and biological oxygen demand (BOD). In addition, the chemical oxygen demands (COD), pH and chloride (Cl). The proposed model performanc
... Show MoreThe performance grading system (superpave) has provided means to incorporate binder characteristics with
pavement failure types. It’s a comprehensive system that relates climate, traffic conditions and aging with
critical pavement distress. The objective of this paper is to develop an improved asphalt binder grading
system for Iraq based on the principal of superpave. The country was divided into different zones according
to the highest and lowest temperature ranges and traffic loading. The Performance graded binder proposed
for each zone was compared with some States of USA that have same hot weather of Iraq by using Long
Term Pavement Performance (LTPP v3.1) software. Iraqi asphalt samples were tested using the Supe
A numerical study has been carried out to investigate heat transfer by natural convection and radiation under the effect of magnetohydrodynamic (MHD) for steady state axisymmetric twodimensional laminar flow in a vertical cylindrical channel filled with saturated porous media. Heat is generated uniformly along the center of the channel with its vertical surface remain with cooled constant wall temperature and insulated horizontal top and bottom surfaces. The governing equations which used are continuity, momentum and energy equations which are transformed to dimensionless equations. The finite difference approach is used to obtain all the computational results using the MATLAB-7 programming. The parameters affected on the system are Rayl
... Show MoreThis study focuses on the simulation of the bed change and total sediment concentration in the Al-Musayyab Canal, which is a vital irrigation system located in the central region of Iraq, using HEC-RAS V 6.3 software. The 49.5 km canal, with 13 branches, faces challenges from sediment influx originating from the Euphrates River. The primary objective is to analyze sedimentation, erosion patterns, and sediment discharge variations to support effective canal management. Field sampling collected suspended and bed load samples for laboratory tests, providing input data for the sediment transport model. Simulation results show steady flow water surface elevations ranging from 26.32 to 33.16 m.a.s.l, with velocities from 0.24
... Show MoreTalking about the construction industry, they frequently characterized by risk, where most of the construction projects involved in the property being fraught with risks and uncertainty, and this is due to the complexity of the industry and the length of the project, and the large number of parties that have a relationship with them. The risks in the projects is a reality that can not be neglected or ignored or canceled, but must be managed properly and so transferred, distributed or transferred, and in any case be required to avoid the impact (if possible) or reduce the losses caused them to a minimum.
It is noted that the bulk of the claims between the contracting parties arising from those risks where those claims either extension
When the flange of a reinforced concrete spandrel beam is in tension, current design codes and specifications enable a portion of the bonded flexure tension reinforcement to be distributed over an effective flange width. The flexural behavior of the RC L-shaped spandrel beam when reinforcement is laterally displaced in the tension flange is investigated experimentally and numerically in this work. Numerical analysis utilizing the finite element method is performed on discretized flanged beam models validated using experimentally verified L-shaped beam specimens to achieve study objectives. A parametric study was carried out to evaluate the influence of various factors on the beam’s flexure behavior. Results showed that
... Show MoreA novel method in induction heating is presented. The winding of the excitation coil is helical and of three –
phase type while the charge is cylindrical. This heating system is compared with the classical induction heating
system of the circular coil type with cylindrical charge and single – phase excitation. The study shows the merits
of the proposed new system over the conventional one. The multi – layer theory approach is adopted for the
analysis of helical winding induction heating system which is an analytical method.
An experimental and theoretical investigation of the effect of flow separation on the performance
of a cascade NACA 65_(12)10 axial compressor blade has been carried out. The experimental work
includes the fabrication of three blades from wood, each having a chord (100mm) but one of these blades having a span of (90mm) for smoke tunnel testing and the other two blades having a span of (380mm) for wind tunnel testing.The two blades were connected by suitable mechanism in order to be fixed in the wind tunnel protractor and rotated in the required stagger angle. The cascade was tested in an open type low-speed subsonic (Mach number=0.117) wind tunnel, for Reynolds number (Re=239605) based on maximum velocity (35 m/s) and airfoil c
The service system has become a necessity of life in modern cities to be the most basic necessities of modern humans, they constitute a major base, which is based on the sustainability of life in the city and a standard measured through the degree of well-being and progress of civilized peoples and their interaction with the surrounding environment, making the services sector as a need not be an option, whenever the cities widened in population and space whenever provision of services and upgrading the quality and quantity more pressing, which made the subject of the services takes the biggest area of the trends and thinking of urban planners and those who in charge of drawing the cities policies. Consideri
... Show MoreThermal buckling analysis of symmetric and antisymmetric cross-ply laminated hybrid composite plates with an inclined crack subjected to a uniform temperature rise are presented in this paper. The first-order shear deformation theory in conjunction with variational energy method is employed in the mathematical formulation. The eight-node Lagrangian finite element technique is used for obtaining the thermal buckling temperatures of hybrid composite laminates. The effects of crack size and lay-up sequences on the thermal buckling temperatures for symmetric and a antisymmetric plates are investigated. The results are shown in graphical form
for various boundary conditions. Finally , from this paper, the following main results have
Minimum-cost well drilling demands the best use of controllable drilling variables for each formation to be drilled. To reach this aim, this study was divided into two main parts: The first part deals with applying a mathematical drilling model to field data of forty wells
drilled at three major oil fields (RU, R, and Z). Bourgoyne & Young (1974) drilling model has been modified to take into consideration the combined effect of weight on bit, rotary speed, bit type, bit size, flow rate, drilling fluid density, drilling fluid viscosity, oil content, bit-nozzle size, formation drillability, formation abrasiveness, bit bearing constant, formation hardness, formation compressive strength, differential pressure between mud column pres
The behavior of structural concrete beams is studied under short-term loading. A computer program developed originally by Oukaili to evaluate curvature is modified to evaluate the deflection for flexural structural concrete members. The program deals with actual stress-strain relationships of concrete and steel. The analysis is based on requirements of equilibrium and compatibility of strain in concrete and reinforcement. The proposed model is used in conjunction with the step by step analysis for small loading increments that allows the determination of the history of strain and stress in concrete with prestressing steel or non-prestressing reinforcement only or prestressing and non-prestressing reinforcement together. The evaluation of
... Show MoreThis paper deals with a Twin Rotor Aerodynamic System (TRAS). It is a Multi-Input Multi-Output (MIMO) system with high crosscoupling between its two channels. It proposes a hybrid design procedure that combines frequency response and root locus approaches. The proposed controller is designated as PID-Lead Compensator (PIDLC); the PID controller was designed in previous work using frequency response design specifications, while the lead compensator is proposed in this paper and is designed using the root locus method. A general explicit formula for angle computations in any of the four quadrants is also given. The lead compensator is designed by shifting the dominant closed-loop poles slightly to the left in the
... Show MoreThe aim of this work is to study reverse osmosis characteristics for copper sulfate hexahydrate
(CuSO4.6H2O), nickel sulfate hexahydrate (NiSO4.6H2O) and zinc sulfate hexahydrate (ZnSO4.6H2O)
removal from aqueous solution which discharge from some Iraqi factories such as Alnasser Company for
mechanical industries. The mode of operation of reverse osmosis was permeate is removed and the
concentrate of metals solution is recycled back to the feed vessel. Spiral-wound membrane is thin film
composite membrane (TFC) was used to conduct this study on reverse osmosis. The variables studied are
metals concentrations (50 – 150 ppm) and time (15 – 90 min). It was found that increasing the time results in an increase in concen
This research presents a new study in reactive distillation by adopting a consecutive reaction . The adopted consecutive reaction was the saponification reaction of diethyl adipate with NaOH solution. The saponification reaction occurs in two steps. The distillation process had the role of withdrawing the intermediate product i.e. monoethyl adipate from the reacting mixture before the second conversion to disodium adipate occurred. It was found that monoethyl adipate appeared successfully in the distillate liquid. The percentage conversion from di-ester to monoester was greatly enhanced (reaching 86%) relative to only 15.3% for the case of reaction without distillation .This means 5 times enhancement . The presence of two layers in both
... Show MoreCorrosion inhibiting admixtures are unique among other methods to protect reinforced concrete from corrosion damage. In this study, the effect of furfural on the fresh and hardened properties of concrete mixes of 35 and 45 MPa compressive strengths as well as the corrosion inhibition of furfural was evaluated. Furfural was added at different dosages (1, 2 and 3% by weight of cement) with and without superplasticizer (HRWR). Different electrochemical measurements were performed (Half-cell potential, Tafel plot and linear polarization resistance). Electrochemical measurements confirmed that furfural dramatically reduces the rate of corrosion; the inhibition efficiencies were 62.7 and 63.8 % due to 3% furfural addition to 35 and 45MPa-concr
... Show MoreIn the present work, the step by step technique is used to predict the performance of the power plant condenser. The procedure includes the calculation of pressure distribution, condensation temperature, water inlet and outlet temperature, condensation load distribution and single phase heat transfer sub-cooling. A quasi two dimensions model is applied, one in the tube water direction and the other in the vapor direction. It is applied with different operating conditions of the condenser such as operating pressure, air percentage mixed with steam, cooling water temperature and fouling factor on tube side for summer and winter seasons.
The present model revealed that the fouling resistance has a great effect and plays the major part of
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Natural convection in an annular space provided with metal foam fins attached to the inner cylinder is studied numerically. The metal foam fins made of copper were inserted in different axial sections with three fins in each section. The temperature of the inner cylinder is kept constant while the annular outer surface is adiabatic. The thickness effect of the inner pipe wall was considered. Naiver Stokes equation with Boussinesq approximation is used for the fluid regime while Brinkman-Forchheimer Darcy model is used for metal foam. In addition, the local thermal non-equilibrium condition in the energy equation of the porous media is presumed. The effect of Rayleigh numb |
Diabetic retinopathy is an eye disease in diabetic patients due to damage to the small blood vessels in the retina due to high and low blood sugar levels. Accurate detection and classification of Diabetic Retinopathy is an important task in computer-aided diagnosis, especially when planning for diabetic retinopathy surgery. Therefore, this study aims to design an automated model based on deep learning, which helps ophthalmologists detect and classify diabetic retinopathy severity through fundus images. In this work, a deep convolutional neural network (CNN) with transfer learning and fine tunes has been proposed by using pre-trained networks known as Residual Network-50 (ResNet-50). The overall framework of the proposed
... Show MoreImproving the accuracy of load-deformation behavior, failure mode, and ultimate load capacity for reinforced concrete members subjected to in-plane loadings such as corbels, wall to foundation connections and panels need shear strength behavior to be included. Shear design in reinforced concrete structures depends on crack width, crack slippage and roughness of the surface of cracks.
This paper illustrates results of an experimental investigation conducted to investigate the direct shear strength of fiber normal strength concrete (NSC) and reactive powder concrete (RPC). The tests were performed along a pre-selected shear plane in concrete members named push-off specimens. The effectiveness of concrete compressiv
... Show MoreThe aim of this study is to propose reliable equations to estimate the in-situ concrete compressive strength from the non-destructive test. Three equations were proposed: the first equation considers the number of rebound hummer only, the second equation consider the ultrasonic pulse velocity only, and the third equation combines the number of rebound hummer and the ultrasonic pulse velocity. The proposed equations were derived from non-linear regression analysis and they were calibrated with the test results of 372 concrete specimens compiled from the literature. The performance of the proposed equations was tested by comparing their strength estimations with those of related existing equations from literature. Comparis
... Show MoreThis research of using Feldspar in the production self compacting concrete (SCC) ( 5,10,15 )% as partial replacement by weight of cement .In this research some of fresh properties of SCC ( slump flow used V-funnel test and filling ability used ( U- box test ) for concrete mixes and also some of the harden properties of SCC ( compressive and flexural tests ). The research results showed that negative effect of Feldspar on the fresh properties of self compacting concrete but the positive effect of Feldspar on the harden properties of self compacting concrete .
Most below-knee prostheses are manufactured in Iraq without considering the fast progress in smart prostheses, which can offer movements in the desired directions according to the type of control system designed for this purpose. The proposed design appears to have the advantages of simplicity, affordability, better load distribution, suitability for subjects with transtibial amputation, and viability in countries with people having low socio-economic status. The designed prosthetics consisted of foot, ball, and socket joints, two stepper motors, a linkage system, and an EMG shield. All these materials were available in the local markets in Iraq. The experimental results showed t
... Show MoreEnvironmental problems created by discarded waste rubbers, such as potential fire and diseas hazards, have become significant in recent years. In connection with rubber recycling, a comparative study of laboratory performance of application of two polymer types: styrene butadiene rubber (SBR) and polyethylene–vinyl acetate (PVA) in asphalt paving mixtures is presented. These mixtures are
usually employed in construction the surface courses in Iraq. These modified asphalt mixtures were prepared with asphalt cement previously modified by using three percents of polymer (1, 3 and 5) percent by weight of modified asphalt. Two control mixes are adopted for comparison purpose. The first control mix was produced with 40/50 penetration asph
Twitter is becoming an increasingly popular platform used by financial analysts to monitor and forecast financial markets. In this paper we investigate the impact of the sentiments expressed in Twitter on the subsequent market movement, specifically the bitcoin exchange rate. This study is divided into two phases, the first phase is sentiment analysis, and the second phase is correlation and regression. We analyzed tweets associated with the Bitcoin in order to determine if the user’s sentiment contained within those tweets reflects the exchange rate of the currency. The sentiment of users over a 2-month period is classified as having a positive or negative sentiment of the digital currency using the proposed CNN-LSTM
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