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Article
Speed Control of Separately Excited D.C. Motor using Self-Tuned Parameters of PID Controller
السيطرة على محرك تيار مستمر ذو الاثارة المنفصلة عن طريق التوليف الذاتي لمتغيرات المسيطر التناسبي-التكاملي-التناظري

Author: Dr. Abdul-Kareem Z. Mansoor Dr. Thair A. Salih,
Journal: Tikrit Journal of Engineering Sciences مجلة تكريت للعلوم الهندسية ISSN: 1813162X 23127589 Year: 2013 Volume: 20 Issue: 1 Pages: 1-9
Publisher: Tikrit University جامعة تكريت

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Abstract

This paper presents a simulation and hardware implementation of a closed loop control of a separately excited D.C. motor using a self-tuning PID controller. The PID controller design is based on using the Field Programmable Analog Array (FPAA) technology. Parameters tuning of the PID controller is achieved by using the genetic algorithm (GA). The FPAA controller based technology gives the advantage of low power, no quantization noise, high bandwidth and high speed response. The practical results show that a self-tuning controller can outperform a hand-tuned solution and demonstrate adaptability to plant drift; also it gives very acceptable results in the reduction of overshoot, stability time and the steady-state transient response of the controlled plant

يعرض هذا البحث تحليلا وتطبيقا عمليا للسيطرة المغلقة على محرك تيار مستمر ذو الاثارة المنفصلة بأستخدام مسيطر تناسبي-تكاملي-تفاضلي (PID) ذو التوليف الذاتي. ان تصميم المسيطر (PID) مبني على مبدا استخدام تقنية بوابة المصفوفات التناظرية المبرمجة حقليا (FPAA). وان عملية توليف قيم الثوابت للمسيطر (PID) يمكن تحقيقها باستخدام الخوارزمية الجينية (GA). ان التقنيات المبنية على استخدام المسيطرات التناظرية (FPAA) لها ميزات من حيث قلة استهلاكها للطاقة, قليلة الضوضاء, سعة عرض الحزمة, سرعة استجابة عالية. تبين النتائج العملية بان التوليف الذاتي يمكن ان يحل مسالة التوليف اليدوي ويبين قابليته العالية لاحتواء اي انجراف او انحراف لمنظومة العمل عن عملها الصحيح, وكذلك يعطي نتائج مقبولة جدا من حيث القفزة, زمن الاستقرار, استجابة الحالة العابرة لمنظومة السيطرة.

Keywords

PID controller --- FPAA --- Self-tuning --- GA


Article
Evaluation of frictional forces generated by different brackets and orthodontic wires

Authors: Khulood A. Almakhzomi خلود المخزومي --- Nidhal H. Ghaib نضال حسين غايب
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2013 Volume: 25 Issue: special issue 1 Pages: 126-131
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Sliding mechanics is widely used during orthodontic treatment. One of the disadvantages of thismechanics is the friction generated at the bracket/archwire interface, which may reduce the amount of desiredorthodontic movement obtained. The aim of the present in vitro study was to evaluate and compare the staticfrictional forces produced by two passive self-ligating brackets stainless-steel and hybrid and two conventionalbrackets stainless-steel and monocrystal ligated with stainless-steel ligature wire at two degrees of torque(zero andtwenty) under dry condition.Materials and method: One hundred and sixty brackets were used in this study divided into four groups each groupconsisted of forty brackets these are: Two self-ligating (stainless-steel and Hybrid) while the two conventional typesare the (stainless-steel and monocrystal).twenty of each group examined with 0.016"x0.022"archwire, ten at 0˚ torqueand ten at 20˚ torque while the other twenty of each group examined with 0.019"x0.025", ten at 0˚ torque and ten at20˚ torque.Results: There was a significant different between all groups except in case when self-ligating brackets (both types)ligated to both wires at 0˚torque there was no significant difference.Conclusions: The self- ligating brackets produce significantly lower static friction than the conventional types at bothdegrees of torque. There was no significant different between both self-ligating brackets at0˚torque while at 20˚torque the stainless- steel self –ligating produce lower static friction than the clear self-ligating type

Keywords

static --- friction --- self-ligating --- conventional --- torque


Article
AN ACTIVE SELF-TUNING SUSPENION SYSTEM TO IMPROVE DRIVER COMFORT
نظام تعليق ذو تضبيط ذاتي فعال لتحسين راحة السائق

Author: Dr. Salim Y. Kasim
Journal: Al-Qadisiyah Journal for Engineering Sciences مجلة القادسية للعلوم الهندسية ISSN: 19984456 Year: 2013 Volume: 6 Issue: 3 Pages: 308-314
Publisher: Al-Qadisiyah University جامعة القادسية

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Abstract

This paper presents the simulation of two dimension a half-vehicle self –tuning active suspensionsystem to simultaneously improve vehicle ride comfort. A validated 4-DOF of vehicle linear modelwas used to study the performance of passive suspension system and compared with the developedactive suspension system. The governing equations of motion for the self- tuning active suspensionwas derived and used to reduce the effect of disturbances to the dynamics performance of thevehicle, which appear when the vehicle excited by a semi-circular sinusoidal bump road of a (0.1m) height. The performance of passive suspension and the self-tuning active suspension aredemonstrated by simulations and specially the vertical acceleration and the vertical root meansquare (RMS) acceleration to observe the effect of the proposed system to the ride comfort. Theactive suspension system introduced in this work show good results for improving the ride comfort

في هذا البحث نموذج محاكاةَ لموديل ثنائي البعد خطي ذو اربع درجات من الحرية لنِصْف مركبةِ تحتوي على نظامِ تعليقِ فعالذو تَضْبيط ذاتيِ لتَحسين ا رحةِ ال ا ركب بشكل آني. استند البحث على نموذج خطي كَانَ يُس تَعملُ لدِ ا رسَة أداءِ نظامِ التعليقِ السلبيِللمقارنة بنظامِ التعليقِ النشيطِ المطورِ. تم اشتقاق المعادلات الحَاكِمة للحركةِ لنظام التعليقَ النشيطَ واستخدمت بتقليل تأثيرالاضط ا ربات على أداءِ ديناميكا المركبة، الذي يَظْهرُ عندما تثار العربةَ بصدمة طريق على شكل نصف دائري لموجية جيبيهبارتفاع 0.1 متر. إنّ أداءَ التعليقِ السلبيِ وتعليقِ التَضْبيط الذاتيِ النشيطِ تم عرضه بالمحاكاةِ وخصوصاً التعجيلِ العموديِ ومعدل مربع الجذر للتعجيل لمُلاحَظَة تأثيرِ النظامِ المُقتَرَحِ على ا رحةِ ال ا ركب . وقد وجد انه هناك نتائج تظه ا رن نظام التعليقِالنشيطِ المقدم في هذا البحثِ قد اعطى نتائج جيدة لتَحسين ا رحةِ ال ا ركب.


Article
A study to compare the efficiency of different instrumentation systems for cleaning oval-shaped root canals (An in vitro study)

Authors: Tay H. Kadhom طي كاظم --- Walid N. Al-Hashimi وليد الهاشمي
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2013 Volume: 25 Issue: 1 Pages: 49-55
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Proper cleaning and shaping of the whole root canal space have been recognized as a realchallenge, particularly in oval-shaped canals.This in vitro study was conducted to evaluate and compare theefficiency of different instrumentation systems in removing of dentin debris at three thirds of oval-shaped root canalsand to compare the percentage of remaining dentin debris among the three thirds for each instrumentation system.Materials and methods: Fifty freshly extracted human mandibular molars with single straight oval-shaped distal rootcanals were randomly divided into five groups of ten teeth each. Group One: instrumentation with ProTaperUniversal hand instruments, Group Two: instrumentation with ProTaper Universal rotary instruments, Group Three:instrumentation with Revo-Srotary instruments, Group Four: instrumentation withTwisted rotary files and Group Five:instrumentation with Self-Adjusting Files (SAF). Sodium hypochlorite (3%) was used as an irrigant for all groups. Aftercanals preparation, the roots were split longitudinally and photographed with a professional digital camera. Theimages of root sections were then magnified to 100x and the percentage of remaining dentin debris calculated forthe apical, middle and coronal thirds by dividing the pixels occupied by debris at each third by the total pixelsrepresenting the entire area of the canal using Adobe Photoshop CS6. Data were analyzed statistically by ANOVAand LSD at 1% and 5% significant levels.Results: Both ProTaper hand and ProTaper rotary files resulted in significantly cleaner canals than Revo-S and Twistedrotary files at the middle and coronal thirds. The Self-Adjusting Files produced significantly cleaner canals at thethree thirds than all the other groups. The coronal and middle thirds showed a greater amount of remaining dentindebris than the apical third for all groups except a non-significant difference found between the apical and middlethirds in SAF group.Conclusion: The Self-Adjusting Files allowed more efficient cleaning of oval-shaped root canals than hand androtary instruments


Article
Effect of External Sulfate Attack on Self Compacted Concrete
تأثير مهاجمة الاملاح الخارجية على الخرسانة ذاتية الرص

Author: Zena K. Abbas Al-Anbori
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2013 Volume: 31 Issue: 6 Part (A) Engineering Pages: 1092-1106
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

Self-compacting concrete (SCC) is an innovative concrete that does not require vibration for placing and compaction. It is able to flow under its own weight, completely filling formwork and achieving full compaction, even in the presence of congested reinforcement. The effect of external sulfate attack was studied-Es (very sever exposure SO4>10000ppm) according to ACI 318-11. The mix design method of SCC used is according to EFNARC 2002, and then must satisfy the criteria of filling ability, passing ability and segregation resistance. The experimental program focuses to study two different chemical composition of sulfate resistance Portland cement with different percentage of silica fume replacement by weight of cement and W/cm (0.3 and 0.35). The SCC mixes with cement type 1(C3S= 46.39 and C3S/C2S = 1.78) shows more resistance to Es than mixes with cement type 2 (C3S= 61.22 and C3S/C2S =4.44). The SCC mixes containing 10% SF as replacement of cement shows more resistance to external sulfate attack. The percentage of increase is 17.95% for SCC mixes with type 1 cement and W/cm =0.3 and 17.88% for SCC mixes with type 2 cement and W/cm =0.3 compared to reference concrete mixes

الخرسانة ذاتية الرص هي خرسانة غير تقليدية لا تحتاج الى عملية أهتزاز أو رص في التنفيذ. تكون لها القابلية على الانسياب تحت تأثير وزنها, ولها القابلية على ملئ القالب كاملاً حتى في وجود تسليح كثيف . تم دراسة تأثير مهاجمة الاملاح الخارجية القاسية (SO4 > 1000ppm) وحسب متطلبات الجمعية الامريكية 318 لعام 2011 . الخلطات الخرسانية مصممة حسب متطلبات EFNARC لعام 2002 والتي يجب ان تتوافق مع قابليتها على الملئ , الانسياب و مقاومتها للانعزال. البرنامج العملي يركز على دراسة تأثير التركيب الكيماوي للسمنت البورتلاندي المقاوم ,أضافة نسب من ابخرة السيلكا كأستبدال من وزن السمنت و بنسب وزن ماء الى سمنت 0,3 و 0,35.الخلطات الخرسانية ذاتية الرص الحاوية على النوع 1 من السمنت (46,39=C3S و C3S/C2S=1,78) أظهرت مقاومة أعلى لمهاجمة الاملاح الخارجية من الخلطات الحاوية على النوع 2 (61,22=C3S و C3S/C2S=4,44).الخطات الخرسانية ذاتية الرص الحاوية على 10% من أبخرة السيليكا كانت أكثر مقاومة لمهاجمة الاملاح الخارجية و كانت نسبة الزيادة قد وصلت الى 17,95 للنوع 1 من السمنت و 17,88 للنوع 2 من السمنت لنسبة ماء الى سمنت (0,3).


Article
Some Fixed Point Theorems for Generalized Contractive SelfMapping on Cone Metric Space
بعض هبرهناث النقطت الصاهدة لتطبيق ذاتي هنكوش هعون في فضاء كوى الوتري

Author: Tamara Shehab Ahmed تمارة شهاب احمد
Journal: Journal of College of Education مجلة كلية التربية ISSN: 18120380 Year: 2013 Issue: 3 Pages: 69-78
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

In this paper, we prove some fixed point theorems for self mapping satisfying generalized contractive condition in the setting of Cone metric space with assumption that the Cone is non-normal. Our results aregeneralizations of some recent results


Article
The Effects of 2 Types of Cements and 2 Types of Surface Treatments on Shear Bond Strength of Zirconia

Author: Maha A Al-Murad
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2013 Volume: 13 Issue: 3 Pages: 473-481
Publisher: Mosul University جامعة الموصل

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Abstract

The aim of this study is to evaluate the interactive influence of different types of cement and surface treatments on bond strength of zirconia. Materials and Methods: Thirty cylindrical zirconia blocks (Diameter4mm& thickness4mm)were fabricated for the study. All the specimens were ground with 600 grit silicone carbide polishing paper. Zirconia specimens were randomly divided into three main groups. 1stcontrol (600grit) no surface treatment. 2ed the specimens were air-abrasion with 50um aluminum oxide particles (Al2O3). 3 rd the specimens were air-abrasion with 50um aluminum oxide particles (Al2O3)+ silane .Then ,each group was divided into two groups according to the luting cement used which are( Reinforcd glass ionomer cement and dual cure resin cement).The zirconia blocks bonded to the composite blocks using these types of cements. Then each pair of zirconia block and composite was applied to load of( 15 Kg) for 15 minutes in order to standardized the applied pressure for each type of cement . The resin cement was then light polymerized for 30s with LED light at 500mW/cm2 (Ledition, Ivoclar Vivadent, Liechtenstien) at the distance of 1mm from each direction. The specimens were stored for 24 hours at 37℃. Shear bond strength was measured by using Universal Testing Machine, and mode of failure examined by a stereomicroscope. Results: All the zirconia blocks were bonded to the composite blocks by self adhesive resin cement revealed results more preferable than zirconia blocks were bonded to the composite blocks by Reinforced glass ionomer cement. The shear bond strength between Zirconia and self-adhesive resin cement for the surface were treated with Aluminum-oxide air abraded alone, and zirconia surface were treated with Aluminum-oxide air abraded + silane more preferable than shear bond strength cement between Zirconia and Rinforeced glass ionomer cement for the surface were treated with Aluminum-oxide air abraded alone, and zirconia surface were treated with Aluminum-oxide air abraded + silane. Conclusion: Zirconia was more durable with Self-adhesive resin cement than Reinforced glass ionomer cement. Zirconia Surface treatments were very critical for improvement bond strength with cement in addition to the properties of that cement


Article
Frictional Resistance in Self-ligating Orthodontic Brackets and Conventionally Ligated Brackets (An In Vitro Study)

Authors: Fadhil Y Jasim --- Lara R Al-Banaa
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2013 Volume: 13 Issue: 3 Pages: 524-529
Publisher: Mosul University جامعة الموصل

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Abstract

This study was aimed to compare static frictional forces generated by 3 types of brackets (conventional, active self-ligating and passive self-ligating) combined with 3 different sizes of stainless steel wire. Material and Methods: The sample consisted of three types of brackets (Equilibrium 2, Empower, discovery sl) with a slot size 0.022 inch were coupled with 0.020, 0.018×0.025 and 0.019×0.025 inches stainless steel wires, The testing model consists of 6 brackets used to represent lower anterior teeth. Ten tests were carried out for each group of bracket-wire combination in dry state, frictional force were measured by tensile testing machine. A significant P value of 0.05 was predetermined. Results: self-ligating brackets produced significantly lower value (P ≤0.05) of mean of static friction than elastomerically tied conventional bracket. The frictional force increased proportionally to the wire size. Conclusions: The method of ligation appears to be the primary variable responsible for the frictional resistance generated by these types of brackets


Article
Evaluation Of Using Glass Fiber On Properties Of Self-Compacting Concrete
تقييم استخدام الألياف الزجاجية على خواص الخرسانة الذاتية الرص

Author: Mohammed Karem Abd
Journal: journal of kerbala university مجلة جامعة كربلاء ISSN: 18130410 Year: 2013 Volume: 11 Issue: 1 Pages: 16-25
Publisher: Kerbala University جامعة كربلاء

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Abstract

This research aims to evaluate of using the glass fiber on the properties of fresh and hardened self compacting concrete (SCC).The work involves four mixes , the mix proportion of these mixes is(1:1.75:2),and water cement ratio is(0.4), superplasticizer of ( 5 ) % of cement content, limestone powder of (100Kg /m3) ,and glass fiber (0,1,3,5)% of mixes volume respectively . Slumpflow, L-Box and V-funnel tests are using to determine the workability of all mixes, the values of slump flow are (710,680,655,615)mm, the values of t50cm are (2,3,3,5) second, the blocking ratio (H2/H1) values are (0.93, 0.87, 0.86, 0.82) and the flow time through the V-funnel are (6, 9, 11, 12) seconds respectively, the mechanical properties studied in this work are compressive strength with average value of six spacements are (28.6,29.2,29.8,31.5) , (47.3,48.7,51.3,54.7)N/mm2 of (7,28) day ages respectively , and splitting tensile strength with average values of six spacements are (4.1, 4.3,4.6,5.1) , (5.2,5.8,6.1,6.5)N/mm2 of (28,56) days ages respectively . Flexural strength (Modulus Of Rupture)(MOR) was tested with average values of three spacements are (4.1,4.3,4.6,5.1) , (5.2,5.8,6.1,6.5)N/mm2 of (28,56) day ages, for glass fiber ratio of (0,1,3,5)% respectively .

يهدف هذا البحث إلى تقييم استخدام الألياف الزجاجية على خواص الخرسانة الذاتية الرص الطرية والمتصلبة وقد تم عمل أربع خلطات خرسانية ذاتية الرص وبنسبة خلط (2:1.75:1) وبنسبة ماء إلى الاسمنت (0.4) ونسبة ملدن متفوق (5)% من وزن السمنت ومادة ناعمة ( الغبرة) (100كغم/م3) ونسبة ألياف (5,3,1,0)% من حجم الخلطة على التوالي . تم فحص قابلية تشغيل الخلطات الخرسانية ذاتية الرص والتي استخدم فيها نسبة ألياف زجاجية (5,3,1,0)% وكان مقدار الانسياب (710 ، 680 ،655 ،615)ملم، وزمن انتشار الخرسانة t50cm هو (5،3،3،2) ثانية، ونسبة الانسداد (H2/H1)في فحص (L-Box) هي (0.93، 0.87، 0.86، 0.82) وزمن الانسياب في فحص (V-funnel) هو (6، 9، 11، 12) على التوالي كما تم فحص مقاومة الانضغاط للخرسانة المتصلبة وكانت قيم معدل المقاومة لستة نماذج هي ( 28.6 ، 29.2 ، 29.8 ، 31.5) و (47.3 ، 48.7 ، 51.3 ، 54.7 ) نيوتن/ملم2 للأعمار ( 7 ، 28 ) يوم على التوالي كما تم فحص مقاومة الانفلاق وكانت قيم معدل المقاومة لثلاثة نماذج هي ( 4.1 ، 4.3 ،4.6 ،5.1 ) و (5.2 ، 5.8 ، 6.1 ، 6.5 ) نيوتن / ملم2 للأعمار (28 ،56 ) يوم على التوالي كما تم فحص مقاومة الشد ( معامل التصدع) وكانت قيم هذا المعامل ( معدل ثلاث نماذج) وبالأعمار ( 28 ، 56 ) يوم هي (4.1 ، 4.3 ، 4.6 ، 5.3)، ( 6.4 ، 6.6 ، 7.2 ، 7.5 ) نيوتن /ملم2 لنسب ألياف زجاجية (5،3،1،0) على التوالي .


Article
Combined effect of fineness modulus and grading zones of fine aggregate on fresh properties and compressive strength of self compacted concrete
التاثير المشترك لمعامل النعومة ومناطق تدرج الركام الناعم في الخواص الطرية ومقاومة الانضغاط للخرسانة ذاتية الرص

Authors: Ikram Faroun Ahmed اكرام فرعون احمد --- Abeer Abdulqadir Salih عبير عبد القادر صالح
Journal: Journal of Engineering مجلة الهندسة ISSN: 17264073 25203339 Year: 2013 Volume: 19 Issue: 6 Pages: 774-785
Publisher: Baghdad University جامعة بغداد

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Abstract

Self-compacted concrete (SCC) considered as a revolution progress in concrete technology due to its ability for flowing through forms, fusion with reinforcement, compact itself by its weight without using vibrators and economic advantages. This research aims to assess the fresh properties of SCC and study their effect on its compressive strength using different grading zones and different fineness modulus (F.M) of fine aggregate. The fineness modulus used in this study was (2.73, 2.82,2.9& 3.12) for different zones of grading (zone I, zone II& marginal zone(between zone I&II)) according to Iraqi standards (I.Q.S No.45/1984).Twelve mixes were prepared, each mix were tested in fresh state with slump, V-Funnel and L-Box tests, then 72 concrete cubes of (100*100*100( mm for different mixes were tested for compressive strength after 7 and 28 days of water curing. Results indicated that the combined effect of fineness modulus and grading zone were clear on the passing ability and little effect of grading zone on flow ability and viscosity of fresh SCC properties. Compressive strength decreases with increasing F.M and no effect of grading zone for F.M higher than 2.90.

تعتبر الخرسانة ذاتية الرص ثورة في مجال تكنولوجيا الخرسانة نتيجة لقابليتها على الانسياب خلال القوالب ، انتشارها خلال حديد التسليح ،رصها لنفسها بتاثير وزنها وفائدتها الاقتصادية . يهدف هدا البحث الى تقييم الخواص الطرية للخرسانة ذاتية الرص ودراسة تاثيرها على مقاومة انضغاط تلك الخرسانة باستخدام مناطق تدرج مختلفة ومعامل نعومة متغير للركام الناعم المستعمل في انتاج هذه الخرسانة . معامل النعومة للركام الناعم المستخدم في هذا البحث كان متغير (2.73،2.82،2.9و3.12) ولمناطق تدرج مختلفة (منطقة تدرج رقم 1ومنطقة تدرج رقم 2ومنطقة تدرج مختلفة تقع بين المنطقتين اعلاه) وفق المواصفة القياسية العراقية رقم 45 لسنة 1984. تم تحضير 12 خلطة من الخرسانة ذاتية الرص ،فحصت بحالتها الطرية بفحوصات الهطول ، V-Funnel و L-Box وبعدها تم صب 72 مكعب خرساني بابعاد (100*100*100) ملم وتم اجراء فحص الانضغاط للخلطات المختلفة باعمار 7 و28 يوم اوضحت النتائج ان التأثيرالمشترك لمعامل النعومة ومنطقة التدرج للخرسانة ذاتية الرص في الحالة الطرية يكون اكثر وضوحا في قابلية الانسياب واقل تأثرا، قابلية الملئ واللزوجة .تقل مقاومة الانضغاط مع زيادة معامل النعومة ويقل تاثير منطقة التدرج مع زيادة معامل النعومة الى اعلى من 2.9 .

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