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Article
Evaluation Of The Method Of Stress Characteristics For Estimation Of The Soil Bearing Capacity
تقييم طريقة خصائص الإجهاد في تخمين قابلية تحمل التربة

Authors: Mohammed Y. Fattah --- Mohammed F. Aswad --- Mohammed M. Mahmood
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2008 Volume: 26 Issue: 10 Pages: 1171-1184
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

The classical bearing capacity theories rely on the superposition of three separatebearing capacities – a technique that is inherently conservative – but they also rely ontabulated or curve-fitted values of the bearing capacity factor, Nγ, which may beunconservative. Further approximations are introduced if the footing is circular(multiplicative shape factors are used to modify the plane strain values of , Nc, Nq and Nγ) orif the soil is non-homogeneous (calculations must then be based on some representativestrength). By contrast, the method of stress characteristics constructs a numerical solutionfrom first principles, without resorting to superposition, shape factors or any other form ofapproximation.In this paper, the validation of the method of stress characteristics is tested by solvinga wide range of bearing capacity problems. The results are compared with classical bearingcapacity theories; namely, Terzaghi, Myerhof, Hansen and Vesic methods.It was concluded that the bearing capacity predicted by the method of stresscharacteristics for the case of a circular footing in clay ranges between (3.7 – 4.0) greater thanTerzaghi, Meyerhof, and Vesic methods. This means that the method is not conservative forthis case and can be dependent for economic design of foundations. The bearing capacitypredicted by this method increases linearly with (D/B).For all values of the angle of friction, φ, the method reveals bearing capacity values forsmooth footings greater than Terzaghi and Hansen and smaller than Meyerhof and Vesictheories. Considering the foundation to be rough, the method gives bearing capacity valuesgreater than all other methods. The difference increases as the angle of internal friction(φ) increases. This makes the method unreliable for rough foundations.

إن النظريات التقليدية لحساب قابلية تحمل التربة تعتمد على تجميع ثلاث قابليات تحمل مختلفة (والتي إما أن N_ , هذه التقنية تعتبر ضمنيا تقليدية) و لكنها تعتمد أيضا على قيم معامل قابلية تحمل التربةتكون مرتبة في جداول أو قيم مقربة من المنحنيات وهذه القيم قد تكون غير تقليدية أو مبالغ فيها. و هناكتقريبات إضافية تدخل إذا كان الأساس دائريا (حيث تستعمل معاملات الشكل لتغيير قيم الانفعال المستويأو عندما تكون التربة غير متجانسة (حيث في هذه الحالة يجب أن تكون (N_ و _q وNc للمعاملاتالحسابات مبنية على قيم ممثلة للمقاومة). و بالمقارنة, تقوم طريقة خصائص الإجهاد بإنشاء حل عددي منالمبادئ الأساسية دون الرجوع إلى التجميع أو معاملات الشكل أو أي شكل من أشكال التقريب.في هذا البحث تم اختبار صلاحية طريقة خصائص الإجهاد بحل مدى واسع من مسائل قابليةالتحمل. و قورنت النتائج مع النظريات التقليدية لقابلية التحمل مثل طرق ترزاكي و ميرهوف و هانسن وفسك. و قد وجد أن قابلية التحمل المحسوبة بطريقة خصائص الإجهاد لحالة أساس دائري في الطين أكبر4.0 ) مرة من طرق ترزاكي و ميرهوف و فسك. و هذه يعني أن الطريقة ليست تقليدية لهذه - بحوالي ( 3.7الحالة و يمكن اعتمادها لتصميم اقتصادي للأسس. كما أن قابلية التحمل المحسوبة بهذه الطريقة تزداد خطيا) تعطي هذه الطريقة _ و لجميع قيم زاوية الاحتكاك الداخلي ( .(D/B) مع نسبة العمق إلى عرض الأساسقيما لقابلية التحمل للأسس الملساء أعلى من نظريات ترزاكي و هانسن و أقل من نظريات ميرهوف و فسك.و عند اعتبار الأساس خشنا, تعطي الطريقة قيما لقابلية التحمل أعلى من جميع الطرق الأخرى, و يزداد) و هذا يجعل الطريقة غير معتمدة للأسس الخشنة. _ الفرق مع زيادة زاوية الاحتكاك الداخلي (


Article
PREVALENCE OF ENURESIS IN SAMPLE OF IRAQI CHILDREN

Author: Abdul-Kareem M Ali عبد الكريم محمد علي
Journal: IRAQI JOURNAL OF MEDICAL SCIENCES المجلة العراقية للعلوم الطبية ISSN: P16816579,E22244719 Year: 2012 Volume: 10 Issue: 1 Pages: 36-41
Publisher: Al-Nahrain University جامعة النهرين

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Abstract

BackgroundEnuresis, which is frequently diagnosed amongst school age children, is an important psychosocial problem for both parents and children.ObjectiveIn the present study we aimed to determine the prevalence and associated risk factors of enuresis in sample of Iraqi children and to identify common methods for its management.MethodsAcross sectional epidemiological study was performed among primary school age children living in Tikrit and Beji cities during the period from the October 2008 to the June 2009. A self-administered questionnaire was prepared for this study and distributed to the parents of 1.150 school age children whom aged 6-12 years.ResultsOf the 1.150 questionnaires distributed, 1000 (87%) were completed. The overall prevalence of nocturnal and diurnal enuresis were 22% (n = 220) and 1.9% (n =25) respectively. Although male gender, low age, history of enuresis among parents, low educational level of the parents, deep sleep, increased number of siblings, increased numbers of people sleeping in the child's room, history of enuresis among siblings, poor school performance and history of recurrent urinary tract infections (UTI) were significantly associated with enuresis, but not with the severe enuresis. The percentage of children with enuresis seen by physician for treatment was 17.2%. The most preferred treatment option for enuresis was medications (59.5%), whereas alarm treatment was the least preferred (2.4%).ConclusionThe results with enuresis prevalence and associated risk factors were comparable to other epidemiological studies from various countries, but it is higher in our country. Furthermore we demonstrated that families in the Tikrit do not pay sufficient attention to enuresis and most of enuretic children do not receive professional treatment.Key WordsEnuresis, family characteristics, prevalence


Article
A New Approach for Representing Photonic Crystal Fiber Index Profile to Determine their Optical Characteristics

Authors: Maan M. Shaker --- Mahmood Sh. Majeed --- Raid W. Daoud
Journal: Iraqi Journal for Electrical And Electronic Engineering المجلة العراقية للهندسة الكهربائية والالكترونية ISSN: 18145892 Year: 2011 Volume: 7 Issue: 1 Pages: 73-77
Publisher: Basrah University جامعة البصرة

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Abstract

A genetic algorithm is implemented to represent thedifferent shapes of Photonic Crystal Fiber (PCF) profile; this isdue to the fact that such fibers have special structure. A novelapproach is suggested which differs from the usual fibers. Byapplying this new approach, more realistic representations oftheir profiles are drawn and hence highly accurate results areobtained including propagation and dispersion characteristics.


Article
The Effect of Using Different Levels of Red Ginseng Roots Powder on some Physiological Characteristics of Japanese Quail Males (Coturnix japonica)

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Abstract

The current study was conducted to investigate the effect of addingdifferent levels of ginseng roots to the diet on some physiological characteristics ofJapanese quail males. A total of 120 Japanese quail males aged one week were used inthis study. The males were randomly distributed into four experimental treatments(n=30). Each treatment was replicated three times (10 individual each). Males were fedexperimental diets that were formulated to contain the same components as the controldiet which contained red ginseng roots powder at levels 250, 500 and 750 mg/ kg feedin other three experimental diets respectively. The results showed that the males of thefourth treatment recorded the lowest mean of the age of sexual puberty. While thehighest average of sexual puberty age was recorded by the males of first treatment. Onthe other hand, the fourth treatment recorded the highest relative weight of testescompared with the other treatments at the age of 30 and 60 days. The results indicatedthat the males of the fourth treatment recorded highest Testosterone, FSH and LH levelscompared with the other treatments at the age of 60 days. We can conclude from thisstudy that the highest concentration of powder ginseng roots (750mg/kg feed) canpromote the development of testes and increase testosterone, FSH and LH hormones inthe serum of Japanese quail males.


Article
Morphologic Characteristics of Tigris River with at Mosul City
مورفولوجية نهر دجلة في مدينة الموصل

Authors: خليل ابراهيم عثمان --- عادل علي بلال --- يعرب ابراهيم سليمان
Journal: Tikrit Journal of Engineering Sciences مجلة تكريت للعلوم الهندسية ISSN: 1813162X 23127589 Year: 2012 Volume: 19 Issue: 3 Pages: 36-54
Publisher: Tikrit University جامعة تكريت

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Abstract

In this research work the morphologic and bed material characteristic for 21 km of Tigris River at Mosul city were studied. Seventy seven cross sections were established on this reach. These cross sections were surveyed. Water surface levels were measured at each section and samples of surface and subsurface of bed material were collected. The concentration of the suspended loads was measured at different time periods.The results show that the river at the studied reach have a different morphology and includes three different shapes (meander part, braided part and straight part), also the rivers contents different bars. The sinuosity of river was 1.3 and bed slope was equal to 5*10-4, the deepest part was extending beside the right bank from upstream of Ninevah Bridge to downstream of Al-Horriya Bridge. The bed of Tigris River at the studied reach is distinguished in two layers surface and subsurface The D50 of these layers was equal to 32 mm and 13 mm respectively .The river bed are approached the armoring condition. The surface bed material particles have mainly a disc shape ,then blade, spherical, cylindrical with percentage 50%, 20%, 18% and 12% respectively.. The concentration of suspended load was in rage of 6-30ppm during the whole year except the rain fall periods where the suspended concentration may increased over 3000ppm.


Article
Air Pollution Effects in Some Plant Leaves Morphological and Anatomical Characteristics within Baghdad City. Iraq

Authors: Abdul-Hameed M.J. Al-Obaidy --- Israa M. Jasim --- Abdul-Rahman A. AlKubaisi
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2019 Volume: 37 Issue: 1 Part (c) special Pages: 84-89
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

Abstract- The present study examined the air pollutants effects in seven plantspecies leaves, Olea europea L., Zizphus spina-christi L. Desf., Conocarpuslancifolius Engl., Albizia lebbeck L. Benth., Eucalyptus camaldulensis Dehnh.,Clerodendron inermis L. Graeth and Dodonaea viscasa Jacq., distribute withinBaghdad city. The leaves sample were collected from May (2016) to April (2017)in five regions within Baghdad city, which are Karrada, Sadr City, Shoula andMansur, as well as Baghdad tourist island as a control region. The Sulfurdioxide (SO2), Nitrogen dioxide (NO2), Carbone monoxide (CO), Volatileorganic compounds (VOCs) and Suspended particulate matter (PM) weremeasured in all study regions. The present study results showed an increase inconcentration of all air pollutants in the four study regions compared toBaghdad tourist island, (SO2) average was (0.56) ppm, while (NO2) averagewas (0.80) ppm, (CO) average was (27.69) ppm, (VOCs) average was (5.99)ppm, while (PM) average was (480.80) μg /m3. The morphological andanatomical characteristics include length, width, area, number of stomata; thenumber of epidermis cells, and stomatal index were measured in plant leaves. E.camaldulensis leaves were recorded highest length rate (11.03) cm, whilehighest width rate (5.51) cm and leaf area rate (49.63) cm2 were recorded in A.lebbeck leaves. The highest number of stomata and epidermal cells were alsorecorded in A. lebbeck leaves (101.25 and 738.85) in respectively. But higheststomatal index value was recorded in D. viscasa leaves (14.21).


Article
The Spatial variation of population's Distribution in the Rural Baghdad Governorate during 1997-2018
التباين المكاني لتوزيع سكان ريف محافظة بغداد لعامي 1997-2018

Author: Wasan Kareem وسن كريم عبد الرضا
Journal: Journal of Tikrit University for the Humanities مجلة جامعة تكريت للعلوم الإنسانية ISSN: 18176798 Year: 2019 Volume: 26 Issue: 11 Pages: 202-225
Publisher: Tikrit University جامعة تكريت

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Abstract

This research deals with the spatial variations of the rural population in the province of Baghdad for the years 1997 – 2018. Returning to the study area during that period, the research highlights the political, social, economic, and military conditions which directly affected the rural units and thus led to the spatial variation during the years examined by the research. The goal of the research, therefore, is to detect these disparities that occurred to the rural population and follow their temporal and spatial dimensions. The research follows statistical methods in examining its problem.

تناول هذا البحث التباينات المكانية لسكان الريف في محافظة بغداد لعامي 1997 – 2018 من ذا التوزيع ومعدلات النمو والكثافة السكانية والتركز السكاني وانماط التوزيع فبالرجوع الى منطقة الدراسة خلال تلك المدة يلاحظ الاحداث التي تعرضت لها من الناحية السياسية والاجتماعية والاقتصادية والعسكرية التي اثرت بشكل مباشر على الوحدات الريفية التي يقطنها سكان الريف وادى ذلك الى تباينهم المكاني خلال عامي البحث وعليه هدف البحث الى كشف تلك التباينات التي حصلت لسكان الريف وتتبع بعديها الزماني والمكاني مما يكسب البحث اهميته اتباع الاساليب الاحصائية في بحث وتقصي الظاهرة قيد الدراسة .


Article
Environmental Study of Some Water Characteristics at Um-Al-Naaj Marsh, South of Iraq.
دراسة بيئية لبعض خصائص مياه هور أم النعاج, جنوب العراق

Authors: Mushtak F. Karomi مشتاق فرج كرومي --- Adil H. Talib عادل حسين طالب --- Mohammed J.S. Al-Haidary محمد جواد الحيدري --- Mohammed A. H. Al-Kenzawi محمد عبدالرضا الكنزاوي
Journal: Baghdad Science Journal مجلة بغداد للعلوم ISSN: 20788665 24117986 Year: 2011 Volume: 8 Issue: 1عدد خاص بمؤتمر علوم الحياة Pages: 531-538
Publisher: Baghdad University جامعة بغداد

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Abstract

Um-Al-Naaj region in Al-Hawiezah Marsh, Southern Iraq was chosen to study the environmental variations of some water characteristics during 2008, seasonally. The results showed clear seasonal changes in values of some environmental variables (temperature, depth, light penetration, turbidity, total suspended solids, pH, dissolved oxygen, reactive phosphate, reactive nitrite, and reactive nitrate), while there were no clear seasonal changes in electrical conductivity and salinity values. In addition, high nutrients concentrations and light penetration were noted. Statistical analysis showed significant positive relationship between air and water temperature; electrical conductivity and salinity. Water turbidity was significantly affected by total suspended solids. On the other hand, some of the studied variables had significant negative effects (relative relationships) to each other, when water pH and dissolved oxygen were affected by temperature; total suspended solids and turbidity affected also light penetration.

أختيرت منطقة أم النعاج في هور الحويزة, جنوب العراق لدراسة التغيرات البيئية لبعض مواصفات المياه بصورة موسمية ولتوضيح التأثيرات المتداخلة فيم بينها, خلال سنة 2008. هذه الدراسة لاحظت تغيرات موسمية في قيم بعض المتغيرات البيئية (درجة حرارة الماء, عمق الماء, نفاذ الضؤ، عكورة الماء, العوالق الصلبة الكلية, الأس الهيدروجيني للماء, الأوكسجين المذاب, الفوسفيت الفعال, النتريت الفعال والنترات الفعال). بينما لا توجد تغيرات موسمية واضحة في قيمة التوصيل الكهربائي والملوحة. أضافة الى ان قيم تراكيز المغذيات وعمق الماء ونفاذ الضؤ في هذا الهور كانت عالية. النظام الأحصائي الكونوكي (CCA) وقيمة معامل الأرتباط (r) طبقا لتحليل البيانات. هذه التحاليل الأحصائية بينت بأن هناك علاقة معنوية موجبة بين درجة حرارة الهواء ودرجة حرارة الماء وكذلك بين التوصيل الكهربائي والملوحة بالأضافة الى ان عكورة الماء تتأثر معنويا وبصورة أيجابية بالمواد العالقة الصلبة. من جانب اخر هناك تأثيرات عكسية معنوية بين درجة حرارة الماء والأس الهيدروجيني للماء وأيضا مع تركيز الأوكسجين المذاب, وكذلك المواد العالقة الصلبة وعكورة الماء يؤثران سلبيا وبصورة معنوية على نفاذ الضؤ.


Article
Investigation of plasma characteristics of center region of postcylindrical magnetron sputtering device
دراسة خصائص البلازما في منطقة المركز لمنظومة الترذيذ الماكنترون ذات الأبعاد الأسطوانية

Authors: Qusay A. Abbas قصي عدنان عباس --- Rahman R .Abdula رحمن رستم عبدالله --- Baha T. Chied بهاء طعمة جياد
Journal: Iraqi Journal of Physics المجلة العراقية للفيزياء ISSN: 20704003 Year: 2010 Volume: 8 Issue: 11 Pages: 33-40
Publisher: Baghdad University جامعة بغداد

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Abstract

A d.c. magnetron sputtering system was designed and fabricated. The chamber of this system is consisted from two copper coaxial cylinders. The inner one used as the cathode and the outer one used as anode with magnetic coil located on the outer cylinder (anode). The axial behavior of the magnetic field strength along the cathode surface for various coil current (from 2A to 14A) are shown. The results of this work are investigated by three cylindrical Langmuir probes that have different diameters that are 2.2mm, 1mm, and 0.45mm. The results of these probes show that, there are two Maxwellian electron groups appear in the central region. As well as, the density of electron and ion decreases with increases of magnetic field strengths.

في هذا العمل تم تصميم و تكوين منظومة الترذيذ الماكنترون. ان حجرة هذا المنظومة تتكون من اسطوانتين نحاسيتين ذات محور مشترك. حيث استخدمت الاسطوانة الداخلية كقطب سالب اما الاسطوانة الخارجية استخدمت كقطب موجب حيث يكون الملف المغناطيسي موضوع على السطح الخارجي للاسطوانة الخارجية (الانود). تم دراسة توزيع المجال المغناطيسي المتولد في الملف لتيارات مختلفة تتراوح بين (2 إلى 12 أمبير). ان نتائج هذا العمل قد فحصت باستخدام ثلاثة مجاميع من مجسات الانجمور الأسطوانية مختلفة الأقطار وهي 1 ملي متر,ملي متر 0.45,ملي متر . 2.2أن نتائج هذه المجسات قد بينت بان هناك مجموعتين من الإلكترونات مختلفة الطاقة تخضع لتوزيع ماكسويل تظهر في منطقة المركز. بالإضافة إلى ذلك فقد لوحظ بان كثافة الإلكترون و الأيون تقل مع زيادة قوة المجال المغناطيسي


Article
Analysis of Water Hammer for Al-Kut Water Supply Project Using the Method of Characteristics
تحليل ظاهرة المطرقة المائية لمشروع إسالة ماء الكوت باستخدام طريقة المعادلات المميزه

Author: Hussein Shakir Mahmud Al-Bahrani حسين شاكر محمود البحراني
Journal: Al-Qadisiyah Journal for Engineering Sciences مجلة القادسية للعلوم الهندسية ISSN: 19984456 Year: 2009 Volume: 2 Issue: 3 Pages: 584-595
Publisher: Al-Qadisiyah University جامعة القادسية

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Abstract

In this study, a mathematical model have been prepared for al – Kut water supply project depending upon the numerical methods such as Newton - Raphson method and Gaussian elimination method to solve non – linear simultaneous equations with known boundary condition and by using the characteristic method, the partial differential equations are transformed to ordinary differential equations. In this mathematical model, the values of the generated pressures were calculated when using control devices or without, also, to find the influence of this devices on, the pressure values was found. In addition to, the suitable number of control devices required for each pipeline was found to keep the pressure values within a tolerable limits.This model was applied on a published case study and the results were quite satisfactory.

تم في هذا البحث إعداد نموذج رياضي خاص لمشروع ماء الكوت وذلك بالاستعانة ببعض الطرق العددية كطريقة نيوتن – رافسون وطريقة كاوس للحذف لحل المعادلات الآنية غير الخطية التي تتحكم بالشروط الحدودية. وباستخدام طريقة المعادلات المميزة تم تحويل المعادلات التفاضلية الجزئية الى معادلات تفاضلية اعتيادية.
لقد تم في هذا النموذج إيجاد قيم الضغوط المتولدة في حالة استخدام وفي حالة عدم استخدام اجهزة السيطرة وملاحظة مدى تأثيرها على قيم الضغوط واستخدام العدد المناسب من هذه الاجهزة لكي يمكن المحافظة على قيم الضغوط ضمن حدودها المسموحة. حيث تم التحقق من هذا النموذج بتطبيقه على مسألة منشورة حيث جاءت النتائج متطابقة.

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