AL-Rafidain Engineering Journal (AREJ)

This study has been established for Mosul area by using climatic data and information for estimation of evapotranspiration by using methods (Blany–Criddle), kharrufa, pan evaporation,Fao penman montieth) and comparison between them to reach to the best method this study showed that pan evaporation equation has a very good determination factor with Fao-penman montieth because this method depend on simple and easily obtained information in comparison with other methods so that this method is a more suitable use for Mosul area also this study showed that there is a correlation performance relationship between these method the value of determination factor for Blany – Criddle is (0.9922) and for pan evaporation is (0.9788) and Kharrofa equation (0.9536) in comparison with Fao-penman Montieth .

The present research aims at building of a mathematical model using (Engineering Equation Solver) (EES) software to analyze the flow of the refrigerant R134a into two configurations of adiabatic capillary tubes (straight and helical coiled tubes) which are used widely in a household refrigerator, freezer and water cooler. The governing equations which depend on the conservation of mass, momentum, and energy have been coded in order to calculate the length of the single-phase flow region. Moreover, the two-phase region has been divided numerically depending on homogenous flow assumption after determining the boundary conditions and calculating the physical variables at each point of the numerical divisions by using successive substitution method using iteration loops. Finite difference scheme, the length of the two-phase region and the total length for the capillary tube have also been determined. The results show that the behavior of the flow is similar for both forms with regard to the distribution of variables (pressure and temperature drop, dryness fraction, velocity and entropy) over the whole length , while the helical coiled tube length for all cases is shorter than the straight tube at the same conditions. The main parameters that affect the size of capillary tube and the behavior of refrigerant through it have been shown. The tube length increased with the increase of (condenser temperature, degree of sub-cooling and tube diameter) and decreased with the increase of mass flow rate and roughness. The helical tube length increased by increasing coil diameter and coil pitch . The results of the present study agree with the experimental data of previous works with error not exceeding ±10%

The aim of this research is hydrodynamic analysis for Tigris river reach upstream the Third Bridge in Mosul city, and this reach have three islands changing the flow characteristics of Tigris river in the study area. Two dimensional mathematical model in SMS10.1 with geographical information system and satellite data are using to build the conceptual model for study area. The results showed that the efficiency of the mathematical model in analysis of Tigris river in the study area especially the results were presented by digital maps explain (water surface elevation, flow depth, shear stress, flow velocity, scour and deposition locations), in addition predications the shape of the Tigris river reach in the study area in the future.

The cultural identity of any nation or country can't be confirmed unless the continuity with it's past. The architectural heritage is the most important links with the nation's history, which is formed through several centuries, through interaction with the local environment in all its dimensions, the local climatic condition is the most influential factor.
The research hypothesize that the role played by the climate is distinctive in the urban and architecture scales, In the light of that, the objective of the research is to study the relationship between urban-architectural forms and climate, and exploring the strategies adopted by the traditional city for the climatic adaptations and controlling its influence. The research selects the old city of Mosul as a case study because it has similar urban fabric found in the others traditional Arab cities, which have semi-dry or dry climates.

The non-Darcy mixed convection from a horizontal permeable surface embedded in a saturated porous medium with the simultaneous heat and mass transfer has been studied. Uniform and variable permeability effects are also investigated. Variable surface temperature and concentration was considered as a surface condition. Nonsimilar governing equations are obtained by using a suitable transformation and solved numerically by a finite difference method. It is observed that for uniform permeability surface fluid suction and increasing the power law index, thermal dispersion parameter, and buoyancy ratio increases the heat and mass transfer rates. Surface fluid injection and increasing the inertia effect parameter have opposite effect. Increasing Lewis number decreases the heat transfer rate and increases the mass transfer rate. For any particular parameter, variable permeability enhances the heat and mass transfer rates.

Digital houses have formed an important subject , examined by several architectural studies , which have declared the special effects of the information technology revolution on houses design, especially,its form,function and construction , as well as , special effects on the human activities being practiced in.
This paper has discussed the importance of this subject and its theoretical knowledge , in order to determine the research problem , represented by the ambiguous knowledge in the different aspects of digital houses design , in order to explore design considerations in its design , thus its objective has determined by revealing this and its approach has presented by building up a theoretical framework includes two main aspects, the first includes variables concerning the digital house design , whereas the second , includes variables concerning human activities.
Conclusions have shown different design considerations which have been employed in digital houses designs of the international experiences, as well as determining the priorities of future design treatments .

In this study, modeling of heat transfer from a horizontal tube immersed in a shallow gas fluidized bed was investigated. The Surface Particle Emulsion heat transfer model SPE and the single particle model were used in the present work as theoretical models to calculate the average heat transfer coefficient at the tube surface. On the basis of sectorizing the surface of the tube into the three sections (top, side and bottom), The SPE model was used for the top section of the tube and the single particle model was used for the side and bottom of the tube. The experimental work involved measuring particle residence time at the heat transfer surface by using a 30frame/sec digital camera, and the bubble frequency was used as a measuring tool for predicting the particle residence time at the transfer surface. The results obtained show that the average heat transfer coefficient increases with the decrease in particle diameter and the increase in the height of the tube above the distributor plate, while tube size has a small influence on average heat transfer coefficient. The calculated results obtained from the models agreed reasonably well with experimental data.

The aim of this research paper is to investigate the efficiency of dissimilar friction welded super duplex stainless steel SAF 2507 and mild steel joints. The joints were obtained using rotary friction welding process. Friction pressure and forging pressure are varied in three different cases but rotational speed and friction time are kept constant .The joints were subjected to tensile strength and metallographic study. The tensile strength of welded joints compared to that of SDSS SAF 2507 and mild steel in as received condition. The joint efficiency were calculated .The tensile strength and joints efficiency decreased with increasing friction pressure and forging pressure .The results attributed to change in mechanical, physical properties ,and micro structural changes of welded joints like change in ferrite to austenite percent, precipitation of carbides and nitrides ,sigma phase,….etc.

This research aims to study the effect of temperature on bond strength in air entrained concrete and to find the effect of adding entrained air on the properties of the fresh and hardened Concrete under the influence of high temperatures of different levels (20, 200, 400, 600 ºC). These properties are compared with those for normal concrete . In case of concrete structures exposed to an unexpected fire, changes are found in the properties of the concrete constituents, These changes are evaluated to assess the performance of these concrete structures and determine whether structures are safe or not .The research work includes an experimental study of the mechanical properties of the hardened concrete , and the effect of high temperature and entrained air admixture on concrete behavior including, compressive strength, splitting tensile strength, stress – strain relationship (modulus of elasticity) and bond strength between reinforcement and concrete. The work includes four different percentage of air entrained admixture (Sika_Aer) (0, 0.5, 1.0, 1.5 %) by weight of cement. The effect of these variables on the bond stress between concrete and reinforcement as a result of tensile forces using pullout test are investigated. The Results show that the failure for reinforced concrete bond strength depends on diameter of the steel bar used (Ø10 , Ø 12 and Ø 16 mm) , heating temperature for specimens after (28) days of water curing and also depends on the amount of admixture in concrete (Sika-Aer).

In this paper, a comparison is done between MOS Current Mode Logic (MCML) and Complementary metal Oxide Semiconductor (CMOS) circuits operating in low power application. It is found that MCML logic circuits exhibit a decrease in delay and so decrease in overall power delay product compared with CMOS circuits. The tested inverter, D-latch NAND/AND, XOR/XNOR are optimized for low power and high-speed operation, according to the simulation of the circuits for lower voltage operating at data rate 2.5 GHz. This simulation is done using Advanced Design System(ADS2009).From the results shown it is seen that the MCML logic circuits reveal high efficiency and good performance at low power and high speeds which makes them to be more capable for application in the integrated circuits with high density.

تم في هذا البحث معالجة مياه مجرى الخوصر في مدينة الموصل باستخدام طريقة التخثير بواسطة جرع مختلفة من الشب كمادة مخثرة ، و بعد خروج الماء الرائق من المعالجة بالتخثير تم إخضاعه للمعالجة بالامتزاز من خلال امراره على عمود من الكاربون المنشط . حقق الشب افضل كفاءة إزالة للملوثات المختلفة عند الجرع المثلى (20,15,10) ملغرام/لتر .إذ حققت الجرعة (20) ملغرام/لتر من الشب كفاءة ازالة للكدرة مقدارها (99.9%) و لبعض الخصائص (النحاس ، الكادميوم ، النترات و المواد العضوية COD ) نسب ازالة مقدارها (85% ، 71.3% ، 32.6% ، 33% ) على التوالي . بينما حققت المعالجة الثانوية بالامتزاز بالكربون المنشط كفاءة ازالة مقدارها (99.98%) لما تبقى من الكدرة ، و نسبة ازالة لما تبقى من الملوثات أعلاه (25% ، 44.4% ، 71.4% ، 46.6% ) على التوالي .و حققت جرعة (15) ملغرام/لتر من الشب أعلى كفاءة ازالة لكل من (الرصاص ، العسرة الكلية ، المغنيسيوم و الكالسيوم والصوديوم ) بلغت (68% ، 33.7% ، 19.6% ، 16.6%،36.8% ) على التوالي . بينما حقق الكاربون المنشط في هذه الحالة نسب ازالة لما تبقى من هذه الملوثات بعد عملية التخثير مقدارها ( 33% ، 16% ، 15% ، 18.1% ،31.8% ) على التوالي .كما حققت الجرعة (10) ملغرام/لتر من الشب أعلى كفاءة ازالة للملوثات التالية (الزنك ، الفوسفات و الكلوريدات ) مقدارها (66% ، 41% ، 22.5% ) على التوالي . و اعطى بعد ذلك الكاربون المنشط كفاءة ازالة لما تبقى من هذه الملوثات مقدارها (54% ، 60% ، 35.4% ) على التوالي .و بعد تحليل النتائج تبين ان الماء المعالج ملائم لري معظم المحاصيل،وان جميع قيم الpH ضمن حدود المياه الطبيعية .كما تبين انه ضمن محددات نظام صيانة الانهار والمياه العمومية من التلوث من حيث محتواها من العناصر الثقيلة .الكلمات الدالة :- مجرى الخوصر ، التخثير ، الشب ، الامتزاز ، الكاربون المنشط ، المعادن الثقيلة

In this work the analogue neural network has been realized by electronic devices like Operational Amplifiers and Field Effect Transistor (FET) . The FET transistor has been utilized to self adjust weight function for neural network. By use of drain and source resistance as function of applied voltage on the gate in linear characteristic region , this resistance has been connected to the input of Operational Amplifiers which becomes as weight function of neural network. Implementing these mentioned characteristics for both FET transistor and operational amplifier , the analogue neural network structure like neuron , weights function and activation function have been realized individually by using the National Instrument multisim 10 (NI) Software, then the analogue neural network has been trained successfully by using supervised learning rule like single layer perceptron learning rule and delta learning rule. The results, show good fulfillment of a neural network with analogue hardware devices and verifying the learning rules to train network.

Mechanical vibration is one of the most important phenomena studied by mechanical engineering, as well as other branches of engineering. Since most of the mechanical machines contain rotor shafts, then hard conditions during operation cause many faults to occur, one of which is the unbalance fault. Therefore, this research studies the diagnosis of static unbalance fault that causes the vibration of the rotor shafts, through conducting a real model for the unbalance fault of the rotor shaft in order to obtain the real vibration signal resulting from this fault. Moreover, monitoring the vibration signal in the frequency domain, and detecting the machine condition during operation at different speeds, and with position sensor device three axes for the bearing (horizontal, vertical, and axial). It has been proved that unbalance increases by increasing speed, and it becomes more obvious in the horizontal axis. Detecting faults unbalancing in the rotor shafts can also be done by taking the value of root mean square (RMS), which represents the maximum value that can be taken from the horizontal axis of the bearing. This value can be compared with the international standards (ISO 12372) to ensure being within the allowed limits.

Open Shortest Path First (OSPF) is one of the most widely used intra-domain routing protocol. It is well known that OSPF protocol does not provide flexibility in terms of packet forwarding to achieve any network optimization objective. The common objective of network traffic engineering is to minimize the maximal link utilization in a network in order to accommodate more traffic and reduce the chance of congestion In this paper an algorithm, to solve congestion problem in an OSPF based best effort network, is proposed. This algorithm is called Less-congested Open Shortest Path First (LOSPF). A simple feed-forward neural network is used to predict the congestion problem in the computer network links which are over utilized. The neural network is trained to predict congested links based on a given traffic pattern. These predictions are used to modify Dijkstr's algorithm to select the shortest paths, that excluding those links. Better resource utilization is obtained by applying the resulting paths. This is achieved throughout avoiding congested links and using other links that are underutilized. Comparison between performance of the suggested algorithm and the performance of OSPF that uses Dijkstra's algorithm to find the shortest path. Simulation results show that LOSPF performance is better in term of distributing links utilizations, and the queuing delay in the congested links. In spite of the superiority of the proposed LOSPF algorithm, its execution time is almost same as that of the OSPF

The fundamental unit of building a Network on Chip is the router , it directs the packets according to a routing algorithm to the desired host. In this paper ,a router is designed using VHDL language and implemented on Spartan 3E FPGA with the help of Integrated software environment ( ISE10.1) . The utilization of the Spartan 3E resources is excellent ( for example the number of slices required doesn’t exceed 3%) .After that a (4×4) mesh topology network is designed and implemented using FPGA ( the number of slices is 43% of the available slices ) . An example is applied on the designed Network on Chip (NoC) which validates the design successfully .

دراسة عملية مقارنة لعتبات مركبة خرسانية مسلحة بمقطع T لتوزيعات متنوعة للأوتاد المزودة برؤوس في الأوساط الخرسانية المشدودة للعزوم الموجبة

Infiltration of water in unsaturated soils has long been an interest of study in geotechnical engineering. A wide range in permeability coefficient has been proven to be a major obstacle in analyzing seepage problems. Soil-water characteristic curve (SWCC) is a fundamental constitutive relation for the explanation of the engineering behaviour of unsaturated soil. The effect of anisotropy on SWCC and unsaturated coefficients of permeability and diffusion has been studied in this paper, by taking sets of duplicate disturbed and undisturbed specimens prepared in the vertical, 45º inclined and horizontal directions. The results showed that there is a noticeably anisotropic in the basic characteristics of SWCC and the unsaturated coefficients of permeability and diffusion specially at the low values of suction. The variations of the hydraulic conductivity and vapor diffusivity versus suction gradient were opposite. Furthermore there is a noticeable difference between the disturbed and undisturbed specimens in the SWCC and coefficients of diffusion and permeability.

This paper presented the application of nonlinear finite element models in the analysis of rectangular reinforced concrete beams strengthened with ferrocement in the form of U-jacket by using ANSYS software. The numerical results are compared with the corresponding experimental results of unstrengthened beams. The comparisons are carried out in terms of load- deflection curves at mid-span, and failure loads. The predicted results of reference beam are found to be in good agreement with the experimental results. Effect of number of layers of wire mesh on the strength of analyzed beams strengthened with ferrocement jackets has been studied. The same beam is also analyzed after strengtheing it with U-jacket sheets of Carbone Fiber reinforced Polymer (CFRB) and the predicted results are compared with that of the corresponding beams strengthened with ferrocement jackets. The strengthened beams have shown a remarkable improvement in their performances in terms of load deflection and ultimate load. The Carbone Fiber Polymer U-jacket greatly improved the beam ultimate failure load by about 37.44%.

Urban regeneration requires collaboration of traffic engineers with urban planners and architects to provide decision makers with quantitative assessment of the impact of attempted changes in the urban setting. Simulating traffic is a very powerful assessment tool for both traffic engineers and urban planners to help decision makers in selecting the best alternative solution based on predefined criteria while saving resources with high level of precision and accuracy. In this research paper, six action plans were suggested: provide better pedestrian facilities; provide better parking facilities; organize loading and unloading operations; relocate terminals and public transport routes; propose new circulation plan; and relocate the Police Station on Faisal Street. In accordance with all actions, an optimal traffic circulation scenario (new circulation plan) was compared to the do-nothing circulation scenario (current circulation plan). Macro and micro measures of effectiveness are used to quantitatively compare between the two scenarios. Results showed notable improvements in favor of the proposed new circulation plan; however traffic conditions are expected to significantly improve if the demand implications of adopting the other actions were considered.