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Article
COMPUTER MODELING OF SMART ANTENNA SYSTEM
التصميم البرمجي لنظام الهوائي الذكي

Author: Muhammed salah sadiq محمد صلاح صادق
Journal: Al-Qadisiyah Journal for Engineering Sciences مجلة القادسية للعلوم الهندسية ISSN: 19984456 Year: 2011 Volume: 4 Issue: 3 Pages: 327-339
Publisher: Al-Qadisiyah University جامعة القادسية

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Abstract

This research studied the adaptive smart antenna system using in cellular phone applications using MATLAB simulation.In this work, the proposed novel least mean square algorithm (No-LMS) build and studied the results as comparative work with results of two another algorithms called Standard LMS algorithm (S-LMS), and normalized LMS algorithm (N-LMS). The computer simulation work results based No-LMS algorithm have better performance refer to obtain the optimum convergence factor (CF) and shows that robustness smart system, good tracking capability, and high adaptation accuracy than the other algorithms.The smart antenna system that is based on LMS-algorithms for all types (S-LMS),(N-LMS),and (No-LMS) show that this system is affected by the convergence factor, the computer simulation results shows the minimum mean square error (MSE = 0.007) is obtained for the value of convergence factor equal to (0.2). also the smart system is affected by the number of the antennas are used in smart array and number of samples interval, at least three antennas gives the poor steering of array with large MSE value (0.15).The test of the three algorithms for different values of signal to noise ratio (SNR) show that the (No-LMS) algorithm gives the minimum MSE values compared with the two those obtain from other algorithms.

في هذا البحث تم دراسة نظام الهوائيات التكيفية الذكية المستخدمة في تطبيقات الهاتف الخلوي باستخدام برنامج المحاكاة الماتلاب. وقد تم اقتراح خوارزمية المسماة (No-LMS) ومقارنة أداءها مع الخوارزميات (S-LMS) و(N-LMS) وبينت نتائج الحاسوب أن خوارزمية (No-LMS) أعطت أفضل أداء وأفضل معامل تغطية (CF) عن الخوارزميات الأخرى وفي أسوء الظروف و بينت بان نظام الهوائيات الذكية المستندة إلى الخوارزمية (No-LMS) له قابلية تتبع جيدة ودقة تكييف عالية واستقرارية مقارنة مع الأنظمة المستندة إلى الخوارزميات الأخرى. وبشكل عام كل خوارزميات (LMS) تعاني من التأثر بالأداء بعامل التقارب وان النتائج أظهرت بان أحسن قيمة لعامل التقارب هي ( 0.2=CF) سجلت عند اقل معدل مربع خطا (MSE = 0.007) بالإضافة إلى ذلك فان أنظمة الهوائيات التكيفية تتاثر أيضا بعدد الهوائيات في المصفوفة . و أوضحت النتائج بان كلما زاد عدد الهوائيات فان نسبة مربع الخطأ المحسوبة تكون اقل ويصبح النظام أكثر استقرارا , وعلى الاقل ثلاث هوائيات تعطي توجيه غير جيد للمصفوفة ونسبة خطا عالية تصل الى (0.15).


Article
Immunological aspects of cystic echinococcosis in Erbil
الجوانب المناعية لداء المشوكات الكيسي في أربيل

Author: Hadi M. A. Al-Sakee هادي الساقي
Journal: Zanco Journal of Medical Sciences مجلة زانكو للعلوم الطبية ISSN: 19955588/19955596 Year: 2011 Volume: 15 Issue: 2 Pages: 1-9
Publisher: Hawler Medical Univeristy جامعة هولير الطبية

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Abstract

Background and objectives: Echinococcus granulosus exists as a complex of different strains that differ in a wide variety of criteria that impact on the epidemiology, immunology, pathology and control of hydatid disease. This study was undertaken to investigate both humoral and cellular immune responses that are developed against hydatid cysts in Erbil.Methods: Thirty patients (9 males and 21 female) with surgically confirmed cystic echinococcosis and 10 apparently healthy individuals were included in this study. IgG ELISA was performed to asses humoral immune responses. CD4/ CD8 ratio, eosinophil count and lymphocyte transformation response were done to asses the cellular immune responses. The level of IFN-γ and TNF-α was also assayed.Results: The sensitivity of ELISA to detect anti-hydatid antibodies was shown to be 83.33%. CD4 / CD8 ratio was significantly (P< 0.001) decreased in patients with cystic echinococcosis as compared to normal control group, while eosinophil count (P< 0.001), lymphocyte transformation response (P< 0.001) and IFN-γ level (P< 0.01) were significantly increased. In contrast the level of TNFα was non- significantly changed in echinococcosis patients.Conclusion: The current study showed that the local strain of Echinococcus granulosus induces both cellular and humoral immune responses, and the number of peripheral blood CD8 T cells was significantly increased in cystic echinococcosis patients. However, hyporesponsivness to hydatid specific antigens has not been induced.


Article
Comparison of Practical Investigations for CO Emissions Emitted From Single Cylinder S. I. Engine Fueled With Different Kinds of Hydrocarbon Fuels and Hydrogen
مقارنة عملية لملوثات CO الناتجة من محرك اشتعال بالشرارة أحادي الاسطوانةيعمل بأنواع مختلفة من الوقود الهيدروكاربوني والهيدروجين

Author: Khalil Ibrahim Abaas خليل ابراهيم عباس
Journal: Al-Khwarizmi Engineering Journal مجلة الخوارزمي الهندسية ISSN: 18181171 23120789 Year: 2011 Volume: 7 Issue: 1 Pages: 22-29
Publisher: Baghdad University جامعة بغداد

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Abstract

Liquefied petroleum gas (LPG), Natural gas (NG) and hydrogen were all used to operate spark ignition internal combustion engine Ricardo E6. A comparison of CO emissions emitted from each case, with emissions emitted from engine fueled with gasoline as a fuel is conducted.
The study was accomplished when engine operated at HUCR for gasoline n(8:1), was compared with its operation at HUCR for each fuel. Compression ratio, equivalence ratio and spark timing were studied at constant speed 1500 rpm.
CO concentrations were little at lean ratios; it appeared to be effected a little with equivalence ratio in this side, at rich side its values became higher, and it appeared to be effected by equivalence ratio highly, the results showed that CO emissions resulted from gasoline engine were higher than that resulted from using LPG and NG all the time; while hydrogen engine emitted extremely low CO concentrations.

استخدم الغاز النفطي المسال، الغاز الطبيعي والهيدروجين لتشغيل محرك احتراق داخلي يعمل بالشرارة نوع Ricardo E6 ، ومقارنة ملوثات CO المنبعثة من المحرك مع مثيلاتها عند عمل المحرك بالجازولين.تمت دراسة الملوثات الناتجة عند عمل المحرك بنسبة الانضغاط النافعة العليا للجازولين 8:1، ومقارنتها بعمله بنسبة الانضغاط النافعة العليا لكل وقود على حدة، ودراسة تأثير نسبة الانضغاط والنسبة المكافئة وتوقيت الشرر والسرعة على تراكيز الملوث الناتجة.أظهرت النتائج أن تراكيز CO تكون قليلة في الجانب الضعيف وتتأثر قليلا بالنسبة المكافئة، وتزداد في الجانب الغني، وتتأثر بشكل كبير بالنسبة المكافئة، وأظهرت النتائج أن ملوثات CO الناتجة باستخدام الجازولين أكبر من تلك الناتجة عن استخدام LPG و NG على الدوام، بينما ينتج من استخدام الهيدروجين كوقود تراكيز CO قليلة جدا

Keywords

CO --- gasoline --- LPG --- NG --- hydrogen --- compression ratio --- equivalence ratio --- spark timing


Article
SYNTHESIS AND OPTIMIZATION OF EPICYCLIC-TYPE AUTOMATIC TRANSMISSIONS BASED ON NOMOGRAPHS
دراسه توحيديه لامثلية آليات نقل الحركه كوكبيه التروس بأستخدام النوموغراف

Authors: K. H. Salih خلود حسن صالح --- E. L. Esmail د.عصام العيبي اسماعيل
Journal: Al-Qadisiyah Journal for Engineering Sciences مجلة القادسية للعلوم الهندسية ISSN: 19984456 Year: 2011 Volume: 4 Issue: 3 Pages: 168-185
Publisher: Al-Qadisiyah University جامعة القادسية

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Abstract

A new methodology is developed to design and optimize epicyclic-type automatic transmission gear trains using kinematic nomographs. From such nomographs, the kinematic characteristics of an epicyclic gear mechanism can be expressed in terms of the gear ratios of its gear pairs. The main properties of this methodology are that; from a single nomograph, the angular velocities for all of the coaxial links can be estimated and compared directly without specifying the exact size of each gear, the angular velocities can be arranged in a descending sequence without using complicated techniques, and all of the feasible clutching sequences can be enumerated directly. The optimization procedure to find the optimum gear ratios is applicable to any transmission mechanism composed of two or more fundamental gear entities (FGEs) depending on kinematic and geometric constraints.
The reliability of the methodology is established by applying it to the conventionally available three-velocity Simpson gear train for which optimal gear ratios are fully available. The theoretical results are in complete agreement with the practical applications.

في هذا البحث تم تطوير طريقه جديده للتصميم الامثل للمسلسلات الترسيه الكوكبيه لآليات نقل الحركه الآليه بأستخدام المخططات النوموغرافيه الحركيه. ومن هكذا مخططات نوموغرافيه يمكن التعبير عن السمات الحركيه للآليات كوكبيه التروس بدلاله نسبة اسنان أزواج التروس المكونه لها. أن الخصائص الاساسيه للطريقه هي : أنه يمكن تخمين ومقارنة السرع الدورانيه لجميع الاجزاء الدواره مباشرةً من مخطط نوموغرافي واحد ودون تحديد عدد اسنان التروس ابتداءً ، كما يمكن ترتيب تتابع تعشيق التروس من حيث السرعه الدورانيه الخارجه تنازليا دون استخدام تقنيات حل معقده وتعداد جميع تتابعات تعشيق التروس الممكنه عمليا مباشرةً. ان الاجراءات المثلى للحصول على أمثل النسب السرعيه قابله للنطبيق على أي آليه لنقل الحركه مكونه من وحدتين ترسيتين بنائيتين أو أكثر واعتماداً على المحددات الحركيه والهندسيه.


Article
Tests of Composite Beams with Web Openings

Authors: May J. Hamoodi --- Waleed Kh. Hadi
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2011 Volume: 29 Issue: 10 Pages: 2073-2086
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

The aim of this study is to investigate experimentally the structuralbehavior of simply supported composite beams, in which a concrete slab is connected together with a steel I-beam by means of headed stud shearconnectors under the presence of web openings. Six composite beams withconstant degree of interaction were tested under central concentrated static load. One of the beams is constructed without web opening while the others contain various number, location and shape of openings. Deflection at midspan and at the ends of each opening were observed versus load. The experimental results show that the web openings decrease the strength of composite beams in the range of 19% to 24% for the tested specimens. Distinctive effects for the location, number and shape of openings took place after initiation of section yielding. Different patterns of cracks at concrete slab were observed.


Article
Surgical blood ordering system in Al-Yarmouk Teaching Hospital; lessons to learn from the results based on the Cross matched: Transfused ratio

Authors: Sahar Hisham Abdulrazzaq --- Abbas Hashim Abdulsalam
Journal: Iraq Joural of Hematology المجلة العراقية لامراض الدم ISSN: 20728069/25432702 Year: 2011 Volume: 1 Issue: 1 Pages: 33-37
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

Background: The primary purpose of transfusion medicine is to provide safe and effective blood and its components onneed. New procedures to reduce unnecessary work load are vital to improve the efficiency of blood transfusionservices, therefore, the introduction, reappraisal and rationalization of the surgical blood order schemes areimportant developments in this respect.Aim of the study: To audit the surgical blood ordering system adequacy in Al-Yarmouk Teaching Hospital in comparisonto the defined Cross-matched: Transfused (C:T) ratio standards of the Maximum Surgical Blood OrderingSchedule (MSBOS).Methods: This study was conducted retrospectively in Al-Yarmouk Teaching Hospital blood transfusion center for theyears 2008 and 2009 to evaluate the elective surgical blood ordering system in this hospital which is totallybased on the surgeon's decision, i.e., patient-specific blood ordering schedule (PSBOS). All whole blood unitscross matched and all whole blood units’ transfusion for elective surgical procedures using the major crossmatch technique were included.Results: The amount of blood crossmatched (C) were 14780 units, the amount of blood transfused (T) were 11930 units,and the C:T blood ratio was 1.24:1.The sensitivity, specificity, positive predictive value and negative predictivevalue of the PSBOS are 98.9%, 75.8%, 80.7% and 98.6% respectively.Conclusions: The quite clear success of patient-specific blood ordering system (PSBOS) over the maximum surgical bloodordering schedule (MSBOS) in reducing work load in Al-Yarmouk Teaching Hospital blood transfusion centerentitles the continuation with its application. However, this system needs to be periodically audited because itssuccess may be at least partially explained by that the surgeons are underestimating the expected need for bloodtransfusion in elective procedures and that the transfusions were not all medically justifiable.


Article
Comparison between Direct and Coherent Optical Communication System
مقارنة بين نظام أتصال ضوئي متشاكه ومباشر

Authors: Hadeel A. Hameed هديل علي حميد --- Samar Y. Al-Dabag سمر يونس الدباغ --- Hani J. Kbashi هاني جاسم كباشي
Journal: Baghdad Science Journal مجلة بغداد للعلوم ISSN: 20788665 24117986 Year: 2011 Volume: 8 Issue: 2عدد خاص بمؤتمر الفيزياء Pages: 479-484
Publisher: Baghdad University جامعة بغداد

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Abstract

The work in this paper focuses on the system quality of direct and coherent communication system for two computers. A system quality is represented by Signal to Noise ratio (SNR) and Bit Error Rate (BER). First part of the work includes implementation of direct optical fiber communication system and measure the system quality .The second part of the work include implementation both the( homodyne and heterodyne)coherent optical fiber communication system and measure the system quality . Laser diode 1310 nm wavelength with its drive circuit used in the transmitter circuit . A single mode of 62.11 km optical fiber is selected as transmission medium . A PIN photo detector is used in the receiver circuit. The optical D-coupler was used to combine the optical signal that come from transmitter laser source with optical signal of laser local oscillator at 1310/1550 nm to obtain coherent detection . Results show that for direct detection the SNR and the BER (28.5 dB, 9.64x10-8,) respectively, while for homodyne and heterodyne coherent detection , the SNR(94.36,97.71)dB and the BER are (1.32x10-22,2.43x10-23) at maximum optical fiber length at 62.11 km. Results show that the homodyne and heterodyne detection are better than direct detection because the large output SNR and low BER of the received signal.

هذا العمل يركز على نوعية االنظام (System quality ) لمنظومة اتصال ضوئي متشاكه ومباشربين حاسبتين. نوعية االنظام تتمثل بحساب كل من نسبة الاشارة الى الضوضاء (SNR) و بمعدل الخطأ في نقل البيانات (BER) .الجزء الاول من العمل تضمن تنفيذ لمنظومة اتصال مباشربين حاسبتين وحساب نوعية االنظام. اما الجزء الثاني من العمل تضمن تنفيذ لمنظومة اتصال متشاكه (متجانس والغير متجانس )وحساب نوعية االنظام لاجل المقارنة بين المنظومتين .استخدم ليزر دايود ذو الطول الموجي1310nm ودائرة السوق في دائرة المرسلة. ا ختير الليف الضوئي من نوع احادي النمط كوسط ناقل طوله62.11km. استخدم مستقبل الاشارة البصرية من نوع الكاشف الضوئي PIN الروابط الضوئية من نوع D استخدمت لدمج الاشارة البصرية القادمة من المصدر الليزري المرسل مع الاشارة البصرية لليزر المذبذب المحلي ذو الطول الموجي 1310 nm و 1550 nm للحصول على الكشف المتشاكه (المتجانس والغير متجانس) . اظهرت النتائج ان معدل الخطأ في نقل البيانات(9.64X10-8,1.32x10-22,2.43x10-23)BER ونسبة الأشارة الى الضوضاء (28.5,94.36,97.71)dB SNR عند اعلى طول لليف البصري 62.11 km لمنظومة اتصال ضوئي مباشر و متشاكه بين حاسبتين .اظهرت النتائج ان منظومة الااتصال الضوئي المتشاكه افضل من منظومة الااتصال الضوئي المباشر وذللك لحصول على قيم عالية لنسبة الأشارة الى الضوضاء وقيم واطئة لمعدل الخطأ في نقل البيانات مقارنة بمنظومة الاتصال المباشر


Article
A New Technique for PAPR Reduction in OFDM System

Author: Ahmed K. Abed احمد كريم عبد
Journal: Thi-Qar University Journal for Engineering Sciences مجلة جامعة ذي قار للعلوم الهندسية ISSN: 20759746 Year: 2011 Volume: 2 Issue: 2 Pages: 41-51
Publisher: Thi-Qar University جامعة ذي قار

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Abstract

Orthogonal frequency division multiplexing (OFDM) is an attractive technique for modern wireless communication. One major drawback of orthogonal frequency division multiplexing schemes is the high peak to average power ratio (PAPR) of the output signal. Selecting mapping (SLM) and partial transmit sequences (PTS) are two important techniques for reducing PAPR, but they need to transmit side information to indicate how the transmitter generates the signals. In this paper, we proposed an efficient technique to reduce PAPR in OFDM system. For this technique, circular shifter used to produce K cyclic sequences from the same information sequence. These sequences XOR with K randomly generated keys, the same keys used in receiver side to detect data. The sequence with the lowest PAPR among K sequences is chosen for transmission. Side Information (SI) is coded using Hamming code and embedded into the information sequence. Computer simulation tests have been applied on BPSK and N= 64 subcarriers OFDM system with the proposed method. Moreover, this system will be evaluated under the effect of AWGN channel. The results exhibit the ability of such technique to reduce the PAPR without major effect on the system performance as compared with the conventional OFDM technique. The PAPR of OFDM signal is further reduced by 4–5 dB by this technique.


Article
Simulation & Performance Study of Wireless Sensor Network (WSN) Using MATLAB

Authors: Qutaiba I. Ali, --- Akram Abdulmaojod --- Hussein Mahmood Mohammed
Journal: Iraqi Journal for Electrical And Electronic Engineering المجلة العراقية للهندسة الكهربائية والالكترونية ISSN: 18145892 Year: 2011 Volume: 7 Issue: 2 Pages: 112-119
Publisher: Basrah University جامعة البصرة

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Abstract

a wierless sensor network consists of spatially distributed autonomous sensor to cooperatively monitor physical or environmental conditionsm such as tempreture, sound, vibration, pressure, motion or pollutants. diffirent approaches have used for simulation and modeling of SN (sensor network) and WSN. Traditional approaches consist of various simulation tools based on different languages such as C, C++ and Java, In this paper , MATLAB (7.6) Simulink was used to build a complete WSN system. Simulation procedure includes building the hardware acchitecture of the transmitting nodes, modeling both the communication channel and the receiving master node architecture. Bluetooth was chosen to undertake the physical layer communication with respect to different channel parameters (i.e. signal to Noise ratio, Attenuation and Interference). the simulation model was examined using diferent topologies under various conditions and numerous results were collected. this new simulation methodology proves the ability of the simulink MATLAB to be a useful and fexible approach to study the effect of diferent physical layer parameters on the performence of wierless sensor network.


Article
PERFORMANCE CHARACTERISTICS OF METHANOL-DIESEL BLENDS IN CI ENGINES
مواصفات أداء خلائط ديزل- ميثانول في محركات الاشتعال بالانضغاط

Author: Khalil Ibrahim Abaas
Journal: Journal of Engineering مجلة الهندسة ISSN: 17264073 25203339 Year: 2011 Volume: 17 Issue: 6 Pages: 1492-1501
Publisher: Baghdad University جامعة بغداد

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Abstract

Owing to the energy crisis and pollution problems of today, investigations have concentrated on decreasing fuel consumption and on lowering the concentration of toxic components in combustion products by using non-petroleum, renewable, sustainable and non-polluting fuels. While conventional energy sources such as natural gas, oil and coal are non-renewable, alcohol can be coupled to renewable and sustainable energy sources. In this study, the combustion characteristics of diesel fuel and methanol blends were compared. The tests were performed at steady state conditions in a four-cylinder DI diesel engine at full load at 1500-rpm engine speed. The experimental results showed that diesel methanol blends provided 12.7% increase in brake-specific fuel consumption due to its lower heating value. The results indicated that methanol may be blended with diesel fuel to be used without any modification on the engine

أهتمت الأبحاث العلمية الحديثة بتقليل استهلاك الوقود وتقليل الملوثات السامة الناتجة من الاحتراق، بسبب الأزمة العالمية الخاصة بالطاقة ومشاكل التلوث، وذلك باستخدام أنواع من الوقود المتجدد، المتوفر وغير مسبب للتلوث، ويمكن اعتبار الكحول مصدر طاقة متجددة ومتوفرة، بينما أنواع الوقود التقليدي مثل الغاز الطبيعي، النفط والفحم غير متجددة.في هذة الدراسة، تمت مقارنة مواصفات أداء وقود ديزل وخلائط من الديزل-الميثانول، وأجريت التجارب باستخدام محرك رباعي الاسطوانات ذي حقن مباشروعند حمل كلي وسرعة 1500 rpm، وبينت النتائج أن خلائط الديزل-الميثانول تسبب ارتفاع في استهلاك الوقود النوعي المكبحي بحدود 12.7 %، بسبب انخفاض القيمة الحرارية له، وبينت النتائج أن الميثانول يمكن استخدامه باضافتة الى وقود الديزل بدون عمل أي تحويرات في المحرك

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