An iterative solution procedure necessarily involves pre- specified convergence criteria to stop teration. The Discrete Differential Dynamic Programming procedure to solve optimization problems formulated by the Dynamic Programming is an iterative solution procedure which, in its traditional form, involves two convergence criteria, namely, (a) and (B). The research used the optimum operation of an existing complex water resources system as a case study. The objective function was formulated as the maximum real monetary return. The formulated optimization model was run for a total of (194) different operation cases. Beside the traditional (a) and (B), seven new styles for a unique convergence criterion were examined in the solution. Consi

This research is concerned with performance of different shapes (parallel plate, grid, corrugated) and materials (polystyrene, polypropylene, P.V.C, and steel) of packing for an air -water- cooling tower. A Mechanical forced draught counter current flow cooling tower of 300 mm x 300 mm, cross-sectional area and 1.65m height was constructed and studied theoretically and experimentally Air flow rates of 0.533,1.035, and 1.774 kg/m2.s were used in conjunction with water flow rates of 1.686, 2.218, and 2.66 kg/m2.s, and water temperature of 40,45,50 °C. The tower characteristics (KG a Z/L) and the volumetric mass and heat transfer coefficients (Kça, hoa and ha) are found to be a function of the water and air flow rates simultaneo

This paper presents the non-linear finite element method to study the behavior of four reinforced rectangular concrete MD beams with web circular openings tested under two-point load. The numerical finite elements methods have been used in a much more practical way to achieve approximate solutions for more complex problems.  The ABAQUS /CAE is chosen to explore the behavior of MD beams. This paper also studies, the effect of both size and shape of the circular apertures of MD beams. The strengthening technique that used in this paper is externally strengthening using CFRP around the opening in the MD beams. The numerical results were compared to the experimental results in terms of ultimate load failure and displace

The present work is concerned with the investigation of the behavior and ultimate capacity of axially loaded reinforced concrete columns in presence of transverse openings under axial load plus uniaxial bending. The experimental program includes testing of twenty reinforced concrete columns (150 × 150 × 700 mm) under concentric and eccentric load. Parameters considered include opening size, load eccentricity and influence of the direction of load eccentricity with respect to the longitudinal axis of the opening. Experimental results are discussed based on load – lateral mid height deflection curves, load – longitudinal shortening behavior, ultimate load and failure modes. It is found that when the direction of load

This investigation presents coupled analyses of an carth-dam problem including all aspects of fluid structure interaction (class I coupling) and soil-pore fluid-structure interaction (class II coupling) under earthquake excitations using the finite element method and its comparison with the uncoupled one. New software for predicting and analyzing coupled behavour is established using the pressure formulation for modelling of the fluid and the u-p formulation for modelling of the soil-pore fluid The staggered partitioned solution technique for coupled field problems is implemented and used in the computer code. This scheme is incorporated in terms of a sequential execution for single-field analyzers. The bounding surface plasticity model

The objective of the study was to predict crop coefficient (K) values for cucumber inside the greenhouse during the growing season 2014, using watermarks gypsum blocks and atmometer c apparatus during the growing stages and to compare the predicted values of the crop coefficient with different methods and approaches. The study was conducted in the greenhouses field within Al-Mahawil Township, 70 km south of Baghdad, Iraq. The watermarks soil water sensors and atmometer apparatus were used to measure crop evapotranspiration and reference evapotranspiration on daily basis, respectively. The comparison and the statistical analysis between the calculated K in this study and values obtained from greenhouse gave a good agreement. The root mean

تعد جودة عملية التصميم مهمة وضرورية لضمان جودة مراحل المشروع الهندسي اللاحقة التنفيذ الاستخدام الصيانة وأن أي تلكؤ أو خلل في هذه المرحلة سينعكس تأثيره على المراحل اللاحقة

بصورة مضاعفة.

يتناول هذا البحث تحديد متطلبات الجودة في التصميم والتي تمثلت بمتطلبات الأداء وقابلية التنفيذ وضبط التصميم وكذلك السيطرة على الكلف أثناء مرحلة التصميم كما تناول البحث تحديد الأسباب المؤدية إلى حدوث مشاكل في التصمي

Reduction of noise and vibration in spur gear experimentally by using asymmetric teeth profiles with tip relief was presented. Both of classical (symmetric) and asymmetric (with and without tip relief) spur gears are used in this work. Gear test rig was constructed to achieve torsional vibration measuring, and two modified cutters are designed and manufactured to achieve tooth profile modifications. First to cut asymmetric gear tooth with pressure angles (14.5^o/25 ^o) without tip relief for loaded and unloaded tooth sides respectively, and second to cut asymmetric gear tooth with pressure angles (14.5^o/25 ^o) for loaded and unloaded tooth sides respectively with tip relief to ach

The aim of the present work to study the effect of changing velocity (Reynold's number) on oxygen cathodic polarization using brass rotating cylinder electrode in 0.1, 0.3 and 0.5N NaCl solutions (PH = 7) at temperatures 40, 50 and 600 C. Cathodic polarization experiments were conducted as a function of electrode rotational speed and concentration.

Now days: large and small manufacturing companies own several numerically controlled (NC) iathe machines. hey are finding that NC/CNC machines can make dramatic saving possible. Certain aspects of NC/CNC shop operations require a high skilled operator level than conventional method. So that the need to develop a computerized technology to support the adoption of these machines and get the maximum benefits that's offer is highly recommended. The present work aims to develop such system that stand over the most modern available technologies to support this task. The system database is used to organize the factory data. The database hold factory lathe machines delinition at current state tooling and the available tools and materials with th

In this paper the effect of engagement length, number of teeth, amount of applied load, wave propagation time, number of cycles, and initial crack length on the principal stress distribution, velocity of crack propagation, and cyclic crack growth rate in a spline coupling subjected to cyclic torsional impact have been investigated analytically and experimentally. It was found that the stresses induced due to cyclic impact loading are higher than the stresses induced due to impact loading with high percentage depends on the number of cycles and total loading time. Also increasing the engagement length and the number of teeth reduces the principal stresses (40%) and
(25%) respectively for increasing the engagement length from (0.15 to 0

This work aims to provide a statistical analysis of metal removal during the Magnetic Abrasive Finishing process (MAF) and find out the mathematical model which describes the relationship between the process parameters and metal removal, also estimate the impact of the parameters on metal removal. In this study, the single point incremental forming was used to form the truncated cone made of low carbon steel (1008-AISI) based on the Z-level tool path. Then the finishing was accomplished using a magnetic abrasive process based on the Box-Behnken design of the experiment using Minitab 17 software was used to finish the surface of the formed truncated cone. The influences of different parameters (feed rate, machining step s

Polypropylene (PP) capillary microtubes hold strong potential for use in advanced liquid cooling systems, but their internal flow behavior remains insufficiently understood. Critical factors—such as capillarity, flow regime, and pressure drop—directly influence their thermal performance and practical applicability. Despite their relevance, detailed studies on these parameters in PP hollow fiber microtubes are lacking. This study addresses that gap through a combined mathematical and microscopic investigation of water flow inside PP microtubes with a 0.6 mm inner diameter. Results show that capillary effects are negligible across all tested conditions, contributing only ~0.2% to ~2.7% to the total pressure drop. Moreo

تبحث هذه الدراسة في أداء ركيزة واحدة ومجموعة ركائز (2×2) تقع بالقرب من منحدر طيني مشبع تحت الأحمال الجانبية الدورية باستخدام تحليل العناصر المحدودة (FEA). أجريت عمليات المحاكاة باستخدام Plaxis 3D مع نموذج التربة المتصلبة (HSM)، والذي يسمح بتمثيل أكثر دقة لسلوك التربة، وخاصة في ظروف التحميل الدوري. أخذ النموذج في الاعتبار التربة الطينية ذات المعلمات المستمدة من التقرير الجيوتقني الرسمي الذي أعدته مختبرات مكتب الاستش

With the rapid advancement of construction technologies, the architectural envelope of a building has evolved beyond a mere structural element into an integrated system designed to achieve comprehensive environmental comfort by controlling thermal, lighting, and acoustic factors within architectural spaces. This research focuses on the technological activation of building envelopes through modern innovations such as smart glass, adaptive walls, natural ventilation systems, and advanced insulation technologies, all of which contribute to enhancing building performance and promoting sustainability. The study explores key concepts and strategies related to the performance of building envelopes and examines how artificial in

This research on architecture examines the challenges faced by individuals with visual impairments as they navigate schools and other built environments. It highlights the idea of "architectural visual bias," which favors sight over other sensory experiences. The study promotes architectural designs that go beyond visual considerations to enhance sensory interactions, ultimately aiming to make spaces more accessible to those with visual impairments. The objective is to identify the requirements of visually impaired individuals in the built environment, propose design principles and recommendations for inclusive architecture, and create a design for Pacelli School for the blind and partially sighted that embodies inclusiv

In the past years, the use of composite materials in the aircraft industry, among others, has grown immensely Composite systems offer an advantage over traditional aircraft materials (metals) because they tend to exhibit higher strength/weight and stiffness/weight ratios than metals, thus making the aircraft lighter and improving performance. Woven composites are increasingly considered for such applications because they offer ease in manufacturing of complicated geometries, but the mechanical properties for different weave patrons of the material is even less well characterized than that of non-woven (angle-ply) laminates For this reason and because the woven composite mechanical properties is impotent for the theoretical work of the pr

In this work, a novel system is designed to remote monitor / automatic control of the temperature, humidity and soil moisture of the agricultural greenhouses. In the proposed system, the author used the mentioned sensors for monitoring the climatic conditions of the agricultural greenhouses; and the system makes a controlling process to fix the required parameters for plant growth by running / stopping the fan, air exchanger and irrigation devices when any changes happened in these parameters. The presented system is based on XBee protocol in the implemented wireless sensor star topology network (WSN) to monitor the agricultural greenhouses in real time, and used the GSM and Internet technologies to monitor the agricultu

This paper presents numerical and experimental stress analyses to evaluate the contact and bending stresses on the teeth of spiral bevel gear drive. Finite Element Method has been adopted as a numerical technique which accomplished basically by using ANSYS software package. The experimental stress analysis has been achieved by using a gear tooth model made of Castolite material which has photoelastic properties. The main goal of this research is detecting the maximum tooth stresses to avoid the severe areas that caused tooth failure and to increase the working life for this type of gear drives.

Numerous academics have demonstrated the value of immediate communal spaces in residential projects. In contemporary apartment site planning, these places are essential but sometimes ignored and categorized as leftover negative spaces rather than intentional interaction areas, diminishing the conventional forms of interpersonal communication. However, there is no proof of this relationship's causality. This study eliminates this gap and explores whether territoriality function-based building arrangement convex layouts can moderate the link between physical design and social interactions. Since culture and social interaction are closely related, what are the effects of these spaces and their layout on social interaction i

Cams are considered as one of the most important mechanical components that depends the contact action to do its job and suffer a lot of with drawbacks to be predicted and overcame in the design process. this work aims to investigate the induced cam contact and the maximum shear stress energy or (von misses) stresses during the course of action analytically using Hertz contact stress equation and the principal stress formulations to find the maximum stress value and its position beneath the contacting surfaces. The experimental investigation adopted two dimensions photoelastic technique to analyze cam stresses under a plane polarized light. The problem has been numerically simulated using Ansys software version 15 as FE

Gypseous soils can be found in arid and semi arid region. In civil engineering it can be defined that a soil is a gypseous soil when it has gypsum content enough to change the properties of this soil. Collapsibility of these soils was found to be of major importance. The collapsibility of the soil can be estimated from the term "Collapse Potential (CP)" which can be obtained from two types of tests performed in the oedometer device; (1) Single Collapse Test (SCT) and (2) Double Oedometer Test (DOT). In this study, an analysis of the results obtained by 7 researchers in Iraq was performed. The data collected included basic properties for each sample in addition to the results of the two collapsibility tests. A total of 50 samples were ana

In this paper two stages of analysis are studied. In stage I, the influence of crack shape on the
crack-tip stresses, critical loads and subsequent propagation direction is investigated via a simple
analytical model for cracks in homogeneous materials. This model is verified through finite element
simulations using ANSYS. It is demonstrated that accurate predictions of mechanical energy release
rate and crack deflection angle may be obtained from a smaller number of crack shape parameters.
In stage II, this concept is extended to curved cracks in functionally graded materials (FGMs).It is
common that analytical and computational models of fracture in FGMs have focused almost
extensively on straight cracks. If it can

Gypsum Plaster is an important building materials, and because of the availabilty of its raw materials. In this research the effect of various additives on the properties of plaster was studied , like Polyvinyl Acetate, Furfural, Fumed Silica at different rate of addition and two types of fibers, Carbon Fiber and Polypropylene Fiber to the plaster at a different volumetric rate. It was found that after analysis of the results the use of Furfural as an additive to plaster by 2.5% is the optimum ratio of addition to that it improved the flexural Strength by 3.18%.
When using Polyvinyl Acetate it was found that the ratio of the additive 2% is the optimum ratio of addition to the plaster, because it improved the value of the flexural stre

By adding a measure of third harmonic to the output of each phase of three-phase inverter, it is possible to obtain a line-to-line output voltage that is 15 percent greater than that obtainable when pure sinusoidal modulation is employed.
The line-to-line voltage is undistorted. The method permits the inverter to deliver an output voltage approximately equal to the voltage of the ac supply to the inverter. Thus an induction motor of standard rating with respect to the ac supply to the inverter can deliver very nearly full power at rated speed when supplied from the inverter. This is achieved without pulse dropping or any other form of mode changing.

Iraqi paraffin wax (1.0 wt% aromatic content and 4.4 wt% oil content, Basrah origin) was hydro treated over commercial Pt-Re/y-Al203 catalyst in order to study aromatic removal reaction (de-aromatization) kinetics. Reaction temperature varied from 453 to 533 K over a liquid hourly space velocity from 0.5 to 4.2 h. Hydrogen pressure was kept constant throughout all the experiment at 3.6 Mpa with hydrogen to wax ratio about 400 m/m Kinetics analysis showed that the hydro-de-aromatization reaction followed a second order kinetics model. Energy, enthalpy and entropy of activation of hydro-de-aromatization reaction were 17.2 RJ/mole, 13.1 kJ/mole and -16.9 J/mole K, respectively.

It is commonly known that Euler-Bernoulli’s thin beam theorem is not applicable whenever a nonlinear distribution of strain/stress occurs, such as in deep beams, or the stress distribution is discontinuous. In order to design the members experiencing such distorted stress regions, the Strut-and-Tie Model (STM) could be utilized. In this paper, experimental investigation of STM technique for three identical small-scale deep beams was conducted. The beams were simply supported and loaded statically with a concentrated load at the mid span of the beams. These deep beams had two symmetrical openings near the application point of loading. Both the deep beam, where the stress distribution cannot be assumed linear, and the ex

 The two-dimensional, incompressible, and turbulent boundary layer flow over a flat plate

with suction or blowing from a spanwise slot is examined numerically. The mathematical

modeling involves the derivation of the governing partial differential equations of the

problems. These are the continuity, the momentum, the energy and the (K-ε) turbulence

model. Besides, the perfect gas law is also used. A numerical solution of the governing

equations is approximated by using a

The sealing effects of squeeze air film were analyzed experimentally and theoretically The air flow rate and the sealed pressure were measured in a squeeze face seal. The air flow rate can be expressed as the difference between the flow rate by the pumping and the flow rate by the leakage. The air flow rate by the pumping increases proportionally to the square of the vibration amplitude of the surface, as does the sealed pressure. The air flow rate by the leakage increases proportionally to the pressure difference between the vessel pressure and the ambient pressure. The experimental results showed good agreement with the theoretical results.

In this study, a genetic algorithm (GA) is used to detect damage in curved beam model, stiffness as well as mass matrices of the curved beam elements is formulated using Hamilton's principle. Each node of the curved beam element possesses seven degrees of freedom including the warping degree of freedom. The curved beam element had been derived based on the Kang and Yoo’s thin-walled curved beam theory. The identification of damage is formulated as an optimization problem, binary and continuous genetic algorithms
(BGA, CGA) are used to detect and locate the damage using two objective functions (change in natural frequencies, Modal Assurance Criterion MAC). The results show the objective function based on change in natural frequency i