In this paper, an exact stiffness matrix and fixed-end load vector for nonprismatic beams having parabolic varying depth are derived. The principle of strain energy is used in the derivation of the stiffness matrix.
The effect of both shear deformation and the coupling between axial force and the bending moment are considered in the derivation of stiffness matrix. The fixed-end load vector for elements under uniformly distributed or concentrated loads is also derived. The correctness of the derived matrices is verified by numerical examples. It is found that the coupling effect between axial force and bending moment is significant for elements having axial end restraint. It was found that the decrease in bending moment was
in the

 This study deals with thermal cyclic loading phenomena of plates which were fabricated from

composite materials (woven roving fiber glass + polyester) were exposed to (75 C°) temperature

gradient thermal shock for ten times in different stage of conditioning times due to the effect of thermal

fatigue using the method of Levy solution and compared these results with both results from

experimental published work and (ANSYS Ver. 9) program. A composite laminate plate with fiber

The artistic dimension appears as an important factor in urban townscape's identity shaping, as many cities in the world have a different identity through the different artistic elements in it, the artistic dimension is meant within the research (set of artistic elements that can contribute to urban identity shaping, whether on architecture or on urban design in addition to public, urban arts). Many previous global studies have dealt with one type or more of art affecting the urban townscape identity of specific cities as a case study. Thus, we can diagnose the research problem as (the lack of local knowledge about the role of the artistic dimension in all its components in achieving the urban townscape identity), and th

This research deals with the review of former research that made to solve the challenges and complexities of both static and dynamic soil structure interaction through discussing advanced computational models and their applications and exploring methods of solving the challenges of soil structure interaction in foundation engineering to provide a guide for the engineering community through the complexes of soil structure interaction. It was found that the numerical analysis for both static and dynamic soil structure interaction using the finite element method with the aid of advanced computional models is ideal for dealing with the non-linearity of soil and structure properties and loading conditions and that the use of

The seismic design of pile foundations mainly relies on analyzing the seismic response of layered, liquefiable locations. Two design scenarios are taken into consideration from the case histories; the first is how pile foundations react to the stresses and lateral displacements brought on by the lateral dispersion of liquefied soil. The second is how to piles reaction to seismic activity that occurs with the development of high pore water pressures. The PLAXIS 3D software is utilized in this research with a non-linear soil constitutive model (hypoplastic model) for both dry and saturated loose sandy soils under the impact of two earthquakes and the motion of different features to give a complete understanding of the dyna

Stripping is one of the major distresses within asphalt concrete pavements caused due to penetration of water within the interface of asphalt-aggregate matrix. In this work, one grade of asphalt cement (40-50) was mixed with variable percentages of three types of additives (fly ash, fumed silica, and phosphogypsum) to obtained an modified asphalt cement to resist the effect of stripping phenomena .The specimens have been tested for physical properties according to AASHTO. The surface free energy has been measured by using two methods namely, the wilhelmy technique and the Sessile drop method according to NCHRP-104
procedures. Samples of asphalt concrete using different asphalt cement and modified asphalt cement percentages(4.1,4.6 an

In this study, a dynamic analysis of machine foundations under vertical excitations is carried out.
The effect of embedment and foundation geometry has been taken into account. The stiffness and
damping of soil are considered as frequency dependents. A computer program (CPESP) in FORTRAN POWER STATION has been coded to evaluate the stiffness and damping coefficients depending on excitation frequency and embedment depth. Results have shown that increasing the embedment depth leads to increasing the resonant frequency and decreasing the amplitude of vibration.

A research was conducted to determine the feasibility of using adsorption process to remove boron from aqueous solutions using batch technique. Three adsorbent materials; magnesium, aluminum and iron oxide were investigated to find their abilities for boron removal. The effects of operational parameters on boron removal efficiency for each material were determined.
The experimental results revealed that maximum boron removal was achieved at pH 9.5 for magnesium oxide and 8 for aluminum and iron oxide. The percentage of boron adsorbed onto magnesium,aluminum and iron oxide reaches up to 90, 42.5 and 41.5% respectively under appropriate conditions. Boron concentration in effluent water after adsorption via magnesium oxide comply with th

An analysis was performed on the treated water from two water treatment plants in Baghdad
city. This analysis was used to evaluate the stability of the treated water from these plants and
that will flow in the distribution system to consider its corrosivity. The variation in water
stability with time and distance from the north to the south of Baghdad was indicated. The
analysis showed that the flowing water in the distribution system in Baghdad is corrosive to very
corrosive water by calculating Ryznar stability index (RI). In Al- Karkh WTP in the north, RI
maximum ranged between 7.958 to 9.403 where RI minimum ranged between 7.03 to 7.915.
Where in the south Al-Rasheed WTP, RI maximum ranged between 7.119 to 8.63 a

The present work considers an alternative solution for a complex configuration of rotor discs by applying Galerkin Method. The theoretical model consists of elastic shaft carrying number of discs and supported on number of journal bearings. The equation of motion was discretized to finite degree of freedom in terms of the system generalized coordinates. The various effects of the dynamical forces and moments arising from the bearing, discs and shaft were included. Rayleigh beam model is used for analyzing the shaft while the discs are considered rigid . The validity and convergence of the present analysis was carefully checked by comparing with the Finite Element solution. An example of rotor consists of three different size discs and su

The present work reports on the performance of three types of nanofiltration membranes in the removal of highly polluting and toxic lead (Pb²⁺) and cadmium (Cd²⁺) from single and binary salt aqueous solutions simulating real wastewaters. The effect of the operating variables (pH (5.5-6.5), types of NF membrane and initial ions concentration (10-250 ppm)) on the separation process and water flux was investigated. It was observed that the rejection efficiency increased with increasing pH of solution and decreasing the initial metal ions concentrations. While the flux decreased with increasing pH of solution and increasing initial metal ions concentrations. The maximum rejection of lead and cadmium ion

This research presents a study for precipitating phosphorus (as phosphate ion) from simulated wastewater (5ppm initial concentration of phosphorus) using calcium hydroxide Ca(OH)₂ solution. The removal of phosphorus by Ca (OH)₂ solution is expected to be very effective since the chemical reaction is of acid-base type but Ca(OH)₂ forms complex compound with phosphate ions called. Hydroxyapatite Ca₅ (PO₄)₃OH. hydroxyapatite is slightly soluble in water. This research was directed towards sustainable elements as phosphorus. Kinetics of the dissolution reaction of hydroxyapatite was investigated to find the best factors to recover phosphorus. The effect of con

This paper is a study of the effect of natural saliva (oral cavity) and a fluoride mouthwash on dental
amalgams .Two types electrodes were made the first was of a high copper amalgam while the second was
made from a low copper amalgam. They were immersed in two types of electrolytes for twelve hours and the whole galvanic cell was connected to a computer via a potentiosat. Their corrosion currents, corrosion
voltage and corrosion resistance was recorded and compared to find which medium that is usually has the
most severe effect on the amalgams corrosion.

Physical and chemical adsorption analyses were carried out by nitrogen gas using ASTM apparatus at 77 K
and hydrogen gas using volumetric apparatus at room temperature respectively. These analyses were used for
determination the effect of coke deposition and poisoning metal on surface area, pore size distribution and
metal surface area of fresh and spent hydrodesulphurization catalyst Co-Mo\Al2O3 .
Samples of catalyst (fresh and spent) used in this study are taken from AL-Dura refinery.
The results of physical adsorption shows that surface area of spent catalyst reduced to third compare with
fresh catalyst and these catalysts exhibit behavior of type four according to BET classification ,so, the pores
of these sample

There many methods for estimation of permeability. In this Paper, permeability has been estimated by two methods. The conventional and modified methods are used to calculate flow zone indicator (FZI). The hydraulic flow unit (HU) was identified by FZI technique. This technique is effective in predicting the permeability in un-cored intervals/wells. HU is related with FZI and rock quality index (RQI). All available cores from 7 wells (Su -4, Su -5, Su -7, Su -8, Su -9, Su -12, and Su -14) were used to be database for HU classification. The plot of probability cumulative of FZI is used. The plot of core-derived probability FZI for both modified and conventional method which indicates 4 Hu (A, B, C and D) for Nahr Umr forma

The present study deals with the optimum design of self supporting steel communication towers. A special technique is used to represent the tower as an equivalent hollow tapered beam with variable cross section. Then this method is employed to find the best layout of the tower among prespecified configurations. The formulation of the problem is applied to four types of tower layout
with K and X brace, with equal and unequal panels. The objective function is the total weight of the tower. The variables are the base and the top dimensions, the number of panels for the tower and member's cross section areas. The formulations of design constraints are based on the requirements of EIA and ANSI codes for allowable stresses in the members

Premature failure in asphalt concrete pavement has been the main concern for pavement construction companies and engineers in recent years because of the large rise in traffic volume and loads and the temperature extremes in the summer and winter. The use of modifiers in asphalt concrete mixtures has attracted much attention to increase the performance and lifespan of pavements. As nanotechnology developed, several researchers concentrated on how these materials can help increase pavement serviceability by minimizing rutting and moisture damage. This study evaluates the Hydrated Lime (HL) effect by two methods (wet and dry hydrated lime) on the durability of the warm mix asphalt. The first method, HL, has been supplemented to the asphalt

This study used a spray pyrolysis approach to create thin films from SnO₂ doped with 2% Co on a heated glass substrate at 400°C and investigated how the structural and optical characteristics are affected by non-thermal plasma. X-ray diffraction analysis was initially employed to look into the structural characteristics, and the results indicate that the SnO₂ and SnO₂:Co thin film are polycrystalline and have tetragonal structure, peak formation has occurred in (110), (101), and (211), which correlate to the subsequent diffraction angles, respectively (26.55⁰), (33.90⁰), and (51.55⁰). A peak associated with Co was also observed at (311), which is equivalent to the (36.78⁰) diffra

This paper describes the use of microcomputer as a laboratory instrument system. The system is focused on three weather variables measurement, are temperature, wind speed, and wind direction. This instrument is a type of data acquisition system; in this paper we deal with the design and implementation of data acquisition system based on personal computer (Pentium) using Industry Standard Architecture (ISA)bus. The design of this system involves mainly a hardware implementation, and the software programs that are used for testing, measuring and control. The system can be used to display the required information that can be transferred and processed from the external field to the system. A visual basic language with Microsoft foundation cl

In this research a local adsorbent was prepared from waste tires using two-step pyrolysis method. In the carbonization process, nitrogen gas flow rate was 0.2L/min at carbonization temperature of 500ºC for 1h. The char products were then preceded to the activation process at 850°C under carbon dioxide (CO2) activation flow rate of 0.6L/min for 3h. The activation method produced local adsorbent material with a surface area and total pore volume as high as 118.59m2 /g and 0.1467cm3/g, respectively. The produced . local adsorbent (activated carbon) was used for adsorption of lead from aqueous solution. The continuous fixed bed column experiments were conducted. The adsorption capacity performance of prepared activated carbons in this work

The use of lightweight aggregates in cement concrete manufacturing solves the issue of drying shrinkage over the concrete's life span; nevertheless, the use of artificial lightweight sand may increase this issue in the cement mortar. This research looks at how using lighter sand affects the non-mechanical qualities of cement mortar, namely the dry shrinkage property. It was prepared lightweight sand by pulverising pumice stone, screening it through a 1.18 mm sieve, and combining it with regular natural sand in varied amounts. It was tested various replacement percentages for lightweight sand by weight, such as 10%, 12%, 14%, 16%, and 18%, while keeping a single control sample without any lightweight pulverized pumice san

Generally, the homing systems are majorly constructing from three components: the guidance law, the target tracking system, and the missile flight control system. Therefore, in this paper, we construct our homing system from the following components: the proportional navigation guidance law which is considered as the guidance scheme for most homing missile systems, the
electro-optical tracking system, and a tail controlled missile. And subsequently complete mathematical derivations and the demand transfer function formulations of all these three components have been introduced. The proposed homing system is capable to pursuit and hit any target just by specifying the required missile flight time. A SIMULINK software program has been

The main function of a power system is to supply the customer load demands as economically as possible. Risk criterion is the probability of not meeting the load. This paper presents a methodology to assess probabilistic risk criteria of Al-Qudus plant before and after expansion; as this plant consists of ten generating units presently and the Ministry Of Electricity (MOE) is intending to compact four units to it in order to improve the performance of Iraqi power system especially at Baghdad region. The assessment is calculated by a program using Matlab programming language; version 7.6. Results show that the planned risk is (0.003095) that is (35 times) less than that in the present plant risk; (0.1091); which represents respectable imp

The problem of generated waste as a result of the implementation of construction projects, has  been aggravated recently because of construction activity experienced by the world, especially Iraq, which is going through a period of reconstruction, where construction waste represents (20-40%) of the total generated waste and has a negative effect on the environment and economic side of the project. In addition, the rate of consumpted  amounts of natural resources are estimated to be about 40% in the construction industry, so it became necessary to reduce waste and to be manage well. This study aims to identify the key factors affecting waste management through the various phases of the project, and this is accom

This research shows the experimental results of the bending moment in a flexible and rigid raft foundation rested on dense sandy soil with different embedded depth throughout 24 tests. A physical model of dimensions (200mm*200mm) and (320) mm in height was constructed with raft foundation of (10) mm thickness for flexible raft and (23) mm for rigid raft made of reinforced concrete. To imitate the seismic excitation shaking table skill was applied, the shaker was adjusted to three frequencies equal to (1Hz,2Hz, and 3Hz) and displacement magnitude of (13) mm, the foundation was located at four different embedment depths (0,0.25B = 50mm,0.5B = 100mm, and B = 200mm), where B is the raft width. Generally, the maximum bending

Gypseous soils are widely distributed and especially in Iraq where arid area of hot climatic is present. These soils are considered as problematic soils; therefore this work attends to improve the geotechnical properties of such soil and reduce the dangers of collapse due to wetting process. In this research, undisturbed soil sample of 30 % gypsum content from Karbala city is used. The Single Oedometer collapse test is used in order to investigate the collapse characteristics of natural soil and after treatment with 3%, 6%, 9%, 12% and 15% of Cutback Asphalt. Moreover, two selected additive percentages (9% and 12%) are used to evaluate the suitability of using the Cutback Asphalt for improvement of the bearing capacity o

In this paper a robust governor has been designed using H∞ techniques to replace the conventional
governor of the steam turbine of the power system to regulate the frequency of the power grid. The robust governor is synthesized using state-space approach with time variations, neglected dynamics, and constant main steam pressure are considered in the design process. The proposed approach ensures internal stability, satisfying both frequency and time domains requirements, and obtaining minimal performance H∞-norm of the closed-loop system in one burden. The simulations are carried out using MATLAB and the results show that the overall system output performance can be improved using the proposed H∞ robust governor.

The present research is concerned with the future phase-out of halocarbon types of refrigerants used in the vapor compression refrigeration systems. A window-type air conditioner is selected for the tests to be conducted with two different refrigerants. It is well known that these cooling units are wide spread in their applications and are circulating R-22 as a refrigerant. It is intended to replace this type of refrigerant by another type which is considered to be as environmental friendly refrigerant for smooth operation. The refrigerant selected for this object was R-407C for its favorable thermal properties and acceptable pressure and temperature ranges. The effect of replacing this refrigerant as a substitute on the performance of t

Coagulation - flocculation are basic chemical engineering method in the treatment of metal-bearing industrial wastewater because it removes colloidal particles, some soluble compounds and very fine solid suspensions initially present in the wastewater by destabilization and formation of flocs. This research was conducted to study the feasibility of using natural coagulant such as okra and mallow and chemical coagulant such as alum for removing Cu and increase the removal efficiency and reduce the turbidity of treated water. Fourier transform Infrared (FTIR) was carried out for okra and mallow before and after coagulant to determine their type of functional groups. Carbonyl and hydroxyl functional groups on the surface of

The purpose of this paper is to analyze, study and simulate a three-phase induction motor drive using vector (field-oriented) control strategy and PWM current regulated inverter using hysteresis band current controller. The mathematical model of the induction motor and the principle of indirect field-oriented control are introduced. The Sliding Mode Controller with Boundary Layer (SMC-BL) is used as a speed controller and compared with the proportional integral (PI) controller.
A Simulink / Matlab program is written for simulating the induction motor model, SMC-BL and PI controllers and indirect field oriented control. The SMC-BL based system and PI-controller based system are compared from the point of view of speed–time response a