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Article
Shear Strength Prediction for Two-Piles Caps Using Empirical Equations
ايجاد مقاومة القص لقبعات الركائز ذات الركيزتين باستخدام المعادلات الوضعية

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Abstract

This study involves analyzing of two piles-caps together with other available tested pile caps in literature. Many expressions are proposed in the current stydy to predict the diagonal cracking and ultimate shear strengths of pile caps using the nonlinear multiple-regression analysis to the available experimental data. The proposed expressions have minimum values of mean absolute error (MAE) and root mean square error (RMSE), while they have maximum values for coefficient of multiple determinations (R2). For the prediction of diagonal cracking shear strength, two proposed expressions were compared with the available equations. The analysis of pile caps using these equations indicates that the proposed equations results in accurate values closer to experimental results than the available equations. While for the prediction of ultimate shear strength, two proposed expressions were compared with the available equations. The analysis of pile caps using these equations indicate that the proposed equations results in good agreement when compared with the results of the available equations.

تتضمن هذه الدراسة تحليلاً لقبعات الركائز ذات الركيزتين بالاضافة الى تحليل قبعات ركائز اخرى مفحوصة ومتوفرة في ادبيات البحوث السابقة. تم اقتراح اثنا عشر علاقة وضعية لايجاد مقاومة تشقق القص القطري ومقاومة القص القصوى على حده و باستخدام طريقة التحليل الارتدادي المتعدد اللاخطيه للبيانات العملية.استخلصت علاقتين في هذا البحث تخص التنبوء بمقدارمقاومة تشقق القص القطري ومقاومة القص القصوى كلاً على حده حيث تم الحصول على توافق جيد عند المقارنة مع النتائج العملية باستخدام هاتين العلاقتين حيث اظهرت المعادلات المقترحة اقل نسبة من مقاييس الخطأ (Mean Absolute Error-MAE) و (Root Mean Square Error-RMSE) وحققت دقة عالية من حيث تكوين منحني العلاقة (R2 Coefficient of Multiple Determinations-).تم مقارنة نتائج العلاقات المقترحة لايجاد مقاومة تشقق القص القطري مع المعادلات المتوفرة والمطورة سابقاً من قبل باحثين اخرين (Niwa et al., 1987) و(Rao & Injaganeri, 2011). وتبين عملية تحليل قبعات الركائز باستخدام المعادلات المقترحة في هذا البحث دقة في النتائج عند مقارنتها مع نتائج الفحوصات المختبرية ونتائج المعادلات المتوفرة.اما بالنسبة للتنبوء بمقاومة القص القصوى فقد تم اقتراح علاقتين واجريت مقارنة للنتائج المستخلصة مع نتائج المعادلات المتوفرة والمطورة من قبل (BS 8110-1997) و (Rao & Injaganeri, 2011). وقد تبين من خلال التحليل باستخدام المعادلات المقترحة وجود توافق مقبول مع النتائج العملية مقارنة بنتائج المعادلات المتوفرة.

Keywords

Cracking --- Ultimate --- Shear --- Pile Cap --- Regression.


Article
Computer Aided Flank Wear Measurement in End Milling Cutting Tool

Authors: Ali Abbar Khleif --- Mostafa Adel Abdullah
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2016 Volume: 34 Issue: 5 Part (A) Engineering Pages: 959-972
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

Flank wear width is generally recognized as the key indicator for tool life.In the experiments of this study, nine tools made of HSS and stainless steel 316L as work piecewiththreespindlespeeds(550,930 and 1100)rpm and three redial depth of cut (1.5,2 and 2.25)mm were used. The cutting tool wear was measured using optical microscope and vision system based on a proposed algorithm.Maximum and minimum percentage errors in the flank wear width were (8.250% and 0.645 %) respectively. The numerical method used was by a multiple linear and polynomial regression model and developed a polynomial model, especially to predict the flank wear using MATLAB software.Maximum and minimum percentage errors werefound (14% and 0.322 %) respectively.


Article
Predicting the Delivery Time of Public School Building Projects Using Nonlinear Regression

Authors: Zeyad S. M. Khaled --- Raid S. Abid Ali --- Mussab Faleh Hassan
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2016 Volume: 34 Issue: 8 Part (A) Engineering Pages: 1538-1548
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

The delay in delivering public school building projects in Iraq is one of the major problems that face the construction of new school buildings. In order to enable the concerned governmental agencies to predict the expected delivery time of these projects at the time of contract assignment, two forecasting modelsare developed to aid in this matter. After reviewing a wide range of literature to determine the most common causes of delay, a questionnaire is distributed to owners, consultants, supervising engineers and contractors engaged in public school building projects. The results of the questionnaire were analyzed using the relative importance index. Nine most important causes of delay in public school building projects were assured by the respondents namely; the contractor's financial status, delayed interim payments, change orders, contractor rank(classification), work stoppages, contract value, experience of the supervising engineers, contract duration and delay penalty. Historical data concerning these causes was extracted from past records of the General Directorate of School Buildings, thennonlinear regressionwasemployedto develop two models (A & B)that can predict the final delivery time of public school building projectshaving (12) and (18) classes separately, where the Levenberg-Marquardt technique was used to develop the mathematical equations.The developedprediction equations show a degree of average accuracy of (97.79%) for schoolshaving (12) classes and (97.11%) for schools having (18) classes,with (R2) for both NLR models of (81.25%) and (87.58%) respectively.


Article
Selection of Optimum Permeability Estimation Approach in a Heterogeneous Carbonate Reservoir

Authors: Mohsen Saemi --- Ali Mohammad Bagheri
Journal: Journal of Petroleum Research & Studies مجلة البحوث والدراسات النفطية ISSN: 22205381 Year: 2016 Volume: 272 Issue: 13 Pages: 143-153
Publisher: Ministry of Oil وزارة النفط

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Abstract

Determination of permeability is an essential component of reservoir characterization process which is among the key input parameters into a flow simulation models. Permeability modeling in carbonate reservoirs is still a challenge in the world. Permeability is directly determined in the laboratory from core analysis. Alternatively, it can be determined by analyzing well test or well logs. Due to high cost associated with coring and some technical problems, few wells in any given field are cored whereas most wells have wire-line logs. In this study detailed core analysis data including core porosity and core permeability supplemented by well logs and well test data to predict a continuous log derived permeability in un-cored wells in a heterogeneous carbonate reservoir in south west of Iran. The Mishrif reservoir in the studied field consists of limestone and interbedded shale. The field has 3 wells that have recovered cores. Permeability prediction was applied by several methods including: fuzzy logic, neural networks, clustering, empirical methods and regression analysis. These different methods were used to determine the optimal approach for utilizing in the field under study. To test the permeability prediction, the techniques were calibrated in 2 cored wells and blind tested in remaining cored well to see how well estimated permeability fitted the actual core permeability. Among all permeability modeling methods applied in the field, it turned out that electrofacies method and after that artificial neural network have the highest degree of association. Fuzzy logic and regression techniques are average in modeling permeability and empirical methods are not capable for predicting permeability in studied heterogeneous carbonate reservoir. The core analysis from 3 cored-wells was applied to determine permeability in 51 un-cored wells.


Article
BOOSTING CATEGORISATION SYSTEM IN THE UK TRICS DATABASE AND DEVELOPING NEW TRIP PRODUCTION MODELS
تدعيم نظام تجميع استعمالات الارض السكنية في قاعدة بيانات UK TRICS و تطوير نماذج جديدة لانتاج الرحلات

Author: Firas H. A. Asad فراس حسن علوان أسد
Journal: KUFA JOURNAL OF ENGINEERING مجلة الكوفة الهندسية ISSN: 25230018 Year: 2016 Volume: 7 Issue: 1 Pages: 54-66
Publisher: University of Kufa جامعة الكوفة

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Abstract

In the UK, TRICS is a national trip generation databases and system. It is recommended to be used in quantifying traffic impacts of new residential developments. Thus, any enhancement in its methodology will positively influence the transport assessment process. This paper has three objectives; first, to examine the possibility of proposing new statistically-proven grouping for the TRICS residential land use subcategories. The second objective is to use the proposed grouping to construct parsimonious models for home-based trip production that can aid in quantifying traffic impact assessment. The third objective is to examine the validity of the developed models against two of the most internationally recognised trip information systems; the UK TRICS and the US ITE Trip Generation Manual. The statistical analysis ended up with new more accurate grouping where based on it eight trip production model were built. The developed models were found to be practical and rigorous.

في المملكة المتحدة, TRICS يعتبر قاعدة بيانات و نظام توليد رحلات وطني. انه غالبا موصى به ليستخدم في تحديد التاثيرات المرورية للمواقع السكنية الجديدة. لذلك أي تحسين على المنهجية المتبعة في TRICS ستؤثر ايجابا على عملية تقييم النقل. هذا البحث له ثلاثة اهداف؛ الاول, لتحري امكانية اقتراح تجميع جديد - مُحقق احصائيا- للتصنيفات الثانوية لاستعمالات الارض السكنية في قاعدة بيانات TRICS. الهدف الثاني هو لاستخدام التجميع المقترح لانشاء نماذج مقتصدة لانتاج الرحلات التي اساسها البيت التي تستطيع ان تساعد في قياس تقييم الاثار المرورية. الهدف الثالث هو فحص صلاحية النماذج المطورة مقابل اثنين من اهم انطمة معلومات الرحلات المميزة عالميا؛ TRICS في المملكة المتحدة و كراس معهد ITE لتوليد الرحلات في امريكا. التحليلات الاحصائية انتهت الى تجميع اكثر دقةً الذي اعتمادا عليه ثمانية نماذج انتاج رحلات تم بنائها. النماذج المطورة وجدت بانها عملية و دقيقة.


Article
An Experimental Approach and Constructing a New Non-Linear Regression Model for Prediction the Anisotropy Parameters of Annealing Treated Commercially Pure Aluminum Sheets

Authors: Jabbar H. Mohmmed --- Ali A. Mohsen --- Bassam A. Ahmed --- Najmuldeen Yousif Mahmood
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2016 Volume: 34 Issue: 14 Part (A) Engineering Pages: 2775-2783
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

Earing is a common phenomenon in deep drawing process that increases the waste of metal. This phenomena is affected by material anisotropy, thus, it is important to study the effects of material parameters on this material behavior. This paper focuses on identify the optimal condition of annealing treatment which result in higher value of normal anisotropy and lower value of planar anisotropy which lead to reduce the waste material in subsequent forming processes. Therefore, in this study, anisotropic behavior and formability of commercially pure aluminum thin sheets was investigated after annealing the samples at different temperatures (350, 400, and 450) °C. Uniaxial tensile tests were carried out at room temperature (25°C) to evaluate formability parameters. For this purpose different tensile test samples in the directions of 0°, 45° and 90° in respect to the rolling direction were prepared. In addition to, metallographic test was carried out to as-received and annealed samples to observe the changes in microstructure. Plastic strain ratio and planar anisotropy of samples were calculated from the tensile test data. Based on the tensile test results of samples, the earing phenomenon due to planar anisotropy in commercially pure aluminum sheet was analyzed. The results indicate that the annealing at 400°C brought the optimum conditions.Moreover, new regressions model for prediction the anisotropy parameters of sheet metal using statistical techniques (SPSS software) were constructed in this work. The experimental data were compared to those predicting values. A comparison clearly indicates that there are good identification between measured and predicted values with multiple correlation coefficients R of 0.932 and accuracy of about 87 %. The results reveal that the proposed model is effective and reliable tool to obtain accurate prediction of the anisotropy behavior of metal sheets.


Article
PRACTICAL AID TO IDENTIFY AND EVALUATE PLASTICITY, SWELLING AND COLLAPSIBILITY OF THE SOIL ENCOUNTERED IN BADRAH, SHATRA AND NASSIRYA CITIES
مساعدة عملية لتحديد وتقييم اللدونة والانتفاخ والانهيارية للتربة في مدن بدرة والشطرة والناصرية

Author: Abbas Jawad Al-Taie
Journal: Journal of Engineering and Sustainable Development مجلة الهندسة والتنمية المستدامة ISSN: 25200917 Year: 2016 Volume: 20 Issue: 1 Pages: 38-47
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

The plasticity properties of soil are sufficiently variable to offer a simple but practical aid toidentification. This can be done by using their Atterberg limit values as parameters for an identification chart.This paper attempts to identify and evaluate major soil types encountered within the areas of Badrah, Shatra andNassirya Cities based on a large number of laboratory test results conducted to determine its index and physicalproperties. A new line on plasticity chart was established and corresponding to the mean of more than threehundred plasticity tests. The swelling characteristics of investigated soil were evaluated using the classificationsystem developed by Savage (2007). Savage original chart was modified and new chart established at which theestimated gross plasticity index, using an advanced statistical analysis software package named "NumberCruncher Statistical System (NCSS)", with assistance of resulting functional relation and LL and PL can be usedto asses the suspect soil to swell quickly with no need to conducted sieve analysis test. New chart developed toidentify the collapsibility of the investigated soil according to Holtz and Hilf method. The LL and w were usedto evaluate the collapsibility of soil from the established limiting curves.

ان الخصائص اللدنة للتربة متغيرة بما فيه الكفاية لتقديم مساعدات بسيطة ولكنها عملية لتميز التربة. ويمكن القيام بذلك عن طريق استخدامحدود اتربيرغكمؤشرات لمخطط تصنيف التربة. يهدف البحث الحالي إلى تحديد وتقييم أنواع التربة الرئيسية ضمن مدن بدرة و الشطرة والناصرية بالاعتماد على عدد كبير من نتائج الاختبارات المعملية التي أجريت لتحديد مؤشر والخصائص الفيزيائية للتربة. لقد تم إنشاء خط جديد ضمن مرتسم اللدونة بناءاً على نتائج اكثر من ثلاثمائة اختبار للدونة. تم تقييمخصائص الانتفاخ في التربة باستخدام نظام التصنيف الذي وضعه سيفيج عام (2007). تم تعديل المخطط الأصلي لسيفيج وانشاء مخطط جديد باستخدام القيم المخمنة لمؤشر اللدونة الاجماليوذلك باستخدام برنامج التحليل الإحصائي المتقدم المسمى (NCSS)ومساعدة المعادلة التي تم التوصل اليها من البرنامج الاحصائي ونتائج حدي السيولة واللدونة بحيث اصبح بالامكان تقييم قابلية التربة للانتفاخ بسرعة دون الحاجة لإجراء اختبار التحليل المنخلي. تم تطوير مرتسم جديد للتعرف على قابلية الانهيار للتربة استنادا الى طريقة (Holtz and Hilf). تم استخدام حد السيولة ومحتوى الماء الطبيعي للتربة في تقييم انهيارية التربة من منحنيات الحد المعمول بها.


Article
Sparse ridge Sliced inverse quantile regression without quantile crossing

Author: Ali Jawad Kadhim Alkenani
Journal: AL-Qadisiyah Journal For Administrative and Economic sciences مجلة القادسية للعلوم الإدارية والاقتصادية ISSN: 18169171 23129883 Year: 2016 Volume: 18 Issue: 1 Pages: 253-273
Publisher: Al-Qadisiyah University جامعة القادسية

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Abstract

Quantile regression provides a more complete statistical analysis of the stochastic relationships between random variables. While this technique has become very popular as a comprehensive extension of the classical mean regression it nonetheless suffers the problem of crossing of regression functions estimated at different orders of quantiles. Theoretically, the extension of conditional quantiles to higher dimension p of X is straight forward. However, its practical success suffers from the so-called ‘curse of dimensionality’. In this article we propose a method of obtaining quantile regression estimates for high dimension data without the unfavourable quality of quantile crossing. The proposed method is a two step procedure that initially employs sparse ridge sliced inverse regression (SRSIR) to achieve dimension reduction when the predictors are possibly correlated and then followed by the usage of non-parametric method to estimate non-crossing quantile regression. For the second stage of our method we employ double kernel smoothing method (Yu and Jones,1998); monotone-based smoothing method based on the convolution of the distribution (Dette and Volgushev,2008) and joint non-crossing quantile smoothing spline method (Bondell et al., 2010) for estimating the conditional quantile without quantile crossing. Through a simulation and empirical study we compare our estimators with that of Gannon et al. (2004).


Article
Development of Integrated Strategy for Managing Construction Sector in Iraq Project Management Maturity Models

Authors: Ibrahim A. Mohammad --- Faiq M. Sarhan Al-Zwainy --- Saja H. Raheem
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2016 Volume: 34 Issue: 6 Part (A) Engineering Pages: 1131-1141
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

A lot of construction projects fail to complete their processes according plans, leading to financial and technical problems. The paper tries to study the extent to which the application of best management practices will have a quantitative measurable effect on project success. The researcher developed a model to assess project management maturity for a sample study of the Iraqi ministry of construction and housing and public municipalities, then applied regression analysis to find the correlation of the maturity level of the cost, time management and the average project management processes maturity level and also deviation coefficient during the year (2007-2014).


Article
Modeling Cost Overrun of Public Schools Projects
نمذجة الزيادة بتكاليف أنشاء مشاريع المدارس الحكومية

Author: Gafel Kareem Aswed
Journal: journal of kerbala university مجلة جامعة كربلاء ISSN: 18130410 Year: 2016 Volume: 14 Issue: 3 Pages: 102-111
Publisher: Kerbala University جامعة كربلاء

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Abstract

Poor cost performance in construction project is a common problem worldwide resulting in significant amount of cost overrun at account closure. This study aims at to develop model relationship between the amount of the cost overrun (CSTOVR) in schools construction projects and accepted bid price (LCO), estimated cost (ECO), contractor rank (GRA), experience of the supervisor engineer (ENXP), location of project (LOCA), year of contracting (YEAR), and contractual project duration (CDR) as input parameters before work starts. The study covers two story (12 classes) school projects awarded by the lowest bid system completed during (2007-2012) in Karbala province-Iraq. Probability distribution is established for each identified parameter and subsequently a simulation is developed to produces artificial data. The simulated parameters are used to develop the regression models to predict the cost overrun. It is found that the two developed regression models have the ability to predict the cost overrun (CSTOVR) for school projects, as an output, with good accuracy having correlation coefficient (R) of (85.9%) and (85.2%), determination coefficient (R2) of (73.8%) and (72.6%) respectively.

ضعف السيطرة على الكلفة في المشاريع الإنشائية اصبحت ظاهرة شائعة في اغلب دول العالم نتج عنها زيادات واضحة في الكلفة النهائية عند تصفية الحساب. تهدف هذه الدراسة الى نمذجة العلاقة بين الزيادة المتوقعة في كلف انشاء مباني المدارس الثانوية العامة العراقية وبين المدخلات المعلومة قبل بدء التنفيذ التي هي مدة المقاولة, الكلفة التخمينية, خبرة المهندس المشرف, تصنيف المقاول ,كلفة الإحالة , موقع المشروع, وسنة التعاقد . شملت الدراسة مشاريع المدارس الثانوية ذات (12) صف من طابقين والمحالة بنظام أوطأ العطاءات والمنفذة للفترة بين2012-2007 في محافظة كربلاء. تم تحديد التوزيع الاحتمالي لكل عامل من العوامل التي تم تعريفها كمدخلات ومخرجات في النموذج الرياضي لتحليل الانحدار ومن ثم توليد بيانات صناعية (محاكاة) من هذا التوزيع الاحتمالي لاستخدامها في بناء النموذج (الموديل) الرياضي للتنبؤ بزيادة الكلفة. تم التوصل الى ان نموذجا الانحدار اللذان تم بنائهما في هذه الدراسة يمكن استخدام أي منهما للتنبوء بزيادة الكلفة في مشاريع المدارس المماثلة للعينه المستخدمة في هذه الدراسة وبدقة جيدة ومعامل ارتباط (%85.9) و (85.2%) ومعامل تحديد (73.8%) و(72.6%) على التوالي.

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