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Article
Development of a Prototype Renewable Energy System and its Modification to Suit Middle East Applications

Author: Salman K Salman
Journal: Iraqi Journal for Electrical And Electronic Engineering المجلة العراقية للهندسة الكهربائية والالكترونية ISSN: 18145892 Year: 2011 Volume: 7 Issue: 1 Pages: 55-59
Publisher: Basrah University جامعة البصرة

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Abstract

This paper concerns with exploitation of renewableenergy sources for meeting energy requirements of remotelocations. It presents an investigation which is based on apractical project that was executed in collaboration betweenacademia and industry. It involves design and installation of aprototype integrated renewable energy system which consists oftwo 15 kW wind turbines, electrolyser, fuel cell system (FCS)and the associated control equipment. It was installed at thefurthest island of Shetland, North of Scotland, U.K. Thephilosophy used in designing this system is summarised asfollows: During times of high wind, the electricity generated bywind turbines is normally greater than that required by siteelectrical load. The excessive amount of generated electricity isstored into Hydrogen by utilising an electrolyser which is thenused to generate the deficient electric power by the FCS at timesof low wind.

Keywords

Energy System


Article
Enhancement of Hoisting System Performance
تحسين أداء منظومة رافعة

Authors: Ra'ad K. Mohammed Al-Duleimi رعد كاظم محمد الدليمي --- Yarub O. Naji Al-azzawi يعرب عمر ناجي العزاوي
Journal: Al-Khwarizmi Engineering Journal مجلة الخوارزمي الهندسية ISSN: 18181171 23120789 Year: 2010 Volume: 6 Issue: 2 Pages: 62-71
Publisher: Baghdad University جامعة بغداد

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Abstract

In this paper it is required to enhance the performance of a mechanical system (here: a Hoisting System) where it is preferred to lift a different payloads with approximately the same speed of lifting and keeping at the same time the good performance, and this of course needs some intelligence of the system which will be responsible on measuring the present load and taking into account the speed and performance desired in order to achieve the requirements or the criteria. The process therefore is a Mechatronics System design which includes a measuring system, a control or automation technique, and an actuating system. The criteria built here in this research using a given Hoist system's characteristics and parameters and changing one of these parameters by the actuator depending on load value (i.e. making a calibration with which there will be a given value of the intentional parameter at which the speed and performance reach the requirements to any load value).

في هذا البحث مطلوب تحسين اداء نظام ميكانيكي ( والذي هنا هو نظام رافعة) حيث انه يفضل رفع حمولات مختلفة الاوزان او الكتل بنفس السرعة تقريبا وفي نفس الوقت المحافظة على جودة الاداء, وهذا بالطبع يحتاج بعض الذكاء للنظام والذي سيكون مسؤولا عن قياس الوزن المطلوب رفعه ومن ثم اخذ بنظر الاعتبارالسرعة والاداء المرغوبين لتحقيق المتطلبات او المعيار.اذا العملية هنا هي تصميم نظام ميكاترونكس والذي يتالف من نظام قياس, تقنية سيطرة او اتمتة, ونظام تشغيل. بني المعيار هنا في هذا البحث بالاعتماد على خصائص ومتغيرات نظام الرفع وبتغير احد هذا البارمترات بواسطة المشغل بالاعتماد على قيمة الحمل (اي بمعنى اخر عمل معايرة والتي بها سيكون هنالك قيمة معينة للمتغير المقصود الذي به سيكون السرعة والاداء المطلوبين لاي قيمة للحمل).


Article
Synchronization Scheme for Secured Communications System Based on Chaotic Signals

Author: P.E. Steran
Journal: Iraqi Journal of Applied Physics Letters الرسائل العراقية في الفيزياء التطبيقية ISSN: 1999656X Year: 2010 Volume: 3 Issue: 1 Pages: 7-10
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

In this work, a numerical investigation of a synchronization scheme for secure communication implemented with nonlinear optical ring cavities is performed. We have demonstrated that masking the information in a chaotic optical wave from a nonlinear ring cavity is technically feasible in a secured communication system. The synchronization is robust and analog information transmission is suitable for the specific case considered.


Article
Reporting Fine Needle Aspiration Cytopathology (FNAC) of Thyroid Lesion Per Guidelines of Recent Bethesda System For Reporting Thyroid Cytopathology Markedly Reduces Number of Un Necessary Thyroidectomies

Authors: Hussain Abady Aljebori --- Basim Shehab Ahmed --- Hiba Ahmed Gaidan
Journal: Medical Journal of Babylon مجلة بابل الطبية ISSN: 1812156X 23126760 Year: 2017 Volume: 14 Issue: 2 Pages: 309 -316
Publisher: Babylon University جامعة بابل

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Abstract

Estimation of accuracy of fine needle aspiration cytopathology (FNAC) of thyroid in diagnosis of different thyroid lesions, and evaluation of the value of reporting FNAC per guidelines of Bethesda system in reducing the number of un necessary thyroidectomies. This is a case control prospective study conducted on 221 patients with thyroid nodule[s]. Patient were recruited to Cytopathology Department, Al-Yarmouk Teaching Hospital in the period from January 2014 to March 2017. Results of FNAC were reported per recent Bethesda System for Reporting of Thyroid Cytopathology (TBSRTC). Final diagnoses were determined by histopathology of surgically removed thyroid tissues. Females were more than males with a ratio of 5.31/1, median age was 45.67±3.1 years. Twelve of cases (5.43%) categorized as nondiagnostic/ unsatisfactory samples, 128 (57.92%) as benign, and 29 (13.13%) as atypia of undetermined significance/atypical follicular lesion of undetermined significance (AUS/AFLUS), 34 (15.38%) as follicular neoplasm/suspected follicular neoplasm (FN/SFN), 5 (2.26%) as suspicious for malignancy, and 13 cases (5.88%) as malignant. Histopathology found 2 cases from cytopathological benign category, 7 from AUS/AFLUS, 11 from FN/SFN, 3 from SFM, and twelve from malignantcategory to be malignant. FNAC achieved a sensitivity of 85.71%, specificity of 99.21%, positive predictive value of 92.31%, negative predictive value of 98.44%, and total accuracy of 97.87%. Reporting thyroid cytopathology per Bethesda system increases sensitivity, specificity, accuracy of thyroid cytopathology, increases understanding of reporting system by clinician, improves management plans, and reducing number of un necessary thyroidectomies.


Article
System for Archiving and backup data A case study in the General Directorate of Education in Thi Qar province

Author: Mohammad jabber farhan
Journal: DIRASAT TARBAWIYA مجلة دراسات تربوية ISSN: 20794673 Year: 2019 Volume: 12 Issue: 47 Pages: 481-494
Publisher: The Ministry of Education وزارة التربية

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Abstract

في العقود الأخيرة ، شهد العالم تسارعًا في تطوير تكنولوجيا المعلومات وقد استند سبب الانتشار السريع ولا يزال الى عاملين: الأول هو التكلفة المنخفضة نسبيا لامتلاك المعدات وسرعة ايصال البيانات ؛ العامل الثاني هو اعتماد معظم الشركات والمؤسسات الحكومية على التكنولوجيا لتسهيل أعمالها. إن نقص الطاقة الكهربائية في العراق يقلل من أهمية تكنولوجيا المعلومات ويجعلها عبئا أكثر من كونها مفيدة. هذا البحث طور نظام قاعدة بيانات للمستندات في مديرية التربية بمحافظة ذي قار لأرشفة الوثائق وربط عدة وحدات إدارية خارج المديرية لاسلكيا و بناء ذاكرة داخلية لتخزين البيانات في حالة انقطاع التيار الكهربائي عن الخادم المركزي الموجود في المديرية لتخزين وإرسال البيانات المخزنة بعد الاتصال مرة أخرى إلى الخادم حيث لن يكون هناك هدر للبيانات و جهد الموظفين باستعمال لغة برمجية السي شارب في بيئة الدوت نت في إدخال البيانات الاسكيوال سيرفر كقواعد بيانات. لتقييم البحث، تم استعمال الاستبانة(SUS) لتقييم النموذج الاولي وكانت العينة من موظفي مديرية التعليم في ذي قار. برنامج الإحصاء (SPSS) استعمل لتحليل الاستبانة وكانت النتيجة إيجابية .

In recent decades, the world has witnessed acceleration in the development of information technology. The reason for the rapid spread has been based and is still dependent on two factors: firstly the relatively low cost of owning the equipment and the speed of delivery of the information; the third factor is the adoption of most of the companies and governmental institutions on the technology to facilitate their business. The lack of electricity in Iraq eliminates the importance of information technology and makes it a burden rather than a useful one. This research developed a database system for documents in Thi Qar Education Directorate to archive documents from several administrative units outside the Directorate by building an internal memory to store data in the event of power outages from the central server located in the Directorate using the Visual Studio Net , CSharp as programming language and the SQL server to store and send Stored data after the connection back to server. There will not be waste of data and then no lose of the effort of employees in data entry. To evaluate the research, the questionnaire (SUS) was used to assess the prototype and the sample was from Thi Qar's education Directorate staff. Statistical program (SPSS) used for the analysis of the questionnaire and the result was positive


Article
Bandwidth Efficiency Enhancement for OFDM System Using Hybrid Equalization Techniques
تحسین كفاءة الموجة لنظام مزج تقسیم التردد المتعامد باستخدام تقنیات المعادل الھجین

Authors: Thamer M. Jamel --- Ali N. Abdulla
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2009 Volume: 27 Issue: 8 Pages: 1508-1518
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

The Cyclic prefixed OFDM systems are very robust to multipath, provided that the delay spread of the transmission channel is less than the length of the CP inserted between transmitted symbols. Moreover, appending CP to each OFDM symbol decreases the bandwidth efficiency of the OFDM system, since the CP does not carry useful information.To maintain bandwidth efficiency, a time-domain equalizer (TEQ) and frequency-domain equalizer (FEQ) is used in the OFDM system to mitigate ISI and ICI when the CIR interval is larger than the CP interval. However, the performances of these two equalizers aredegraded under severe channel condition. So a proposed hybrid equalizer structure is suggested in this paper. The hybrid equalizer gives about 10dB, 5dB and 3dB advantages at 10-4 BER compared with OT-FEQ, TEQ and PTEQ respectively. This comparison at fd=50Hz with sufficient length of CP. Also, for this case but with an insufficient length ofCP, the hybrid equalizer gives about 8dB and 7dB advantage compared with both TEQ and PTEQ respectively. Moreover, at fd=100Hz with sufficient CP length, the hybrid equalizer gives about 6dB, 3.5dB and 3dB advantage at 10-4 BER compared with OT-FEQ, TEQ andPTEQ respectively. Also, for this case but with an insufficient length of CP, the hybrid equalizer gives about 6dB and 4dB advantage compared with both TEQ and PTEQ respectively.

Keywords

TEQ --- FEQ --- OFDM system


Article
Design and Implementation of Optical Wireless Communication System

Author: Saba A. Shukry
Journal: Al-Fatih journal مجلة الفتح ISSN: 87521996 Year: 2005 Volume: 1 Issue: 23 Pages: 100-110
Publisher: Diyala University جامعة ديالى

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Abstract

In this paper, we have designed and constructed an optical communication system to transmit two-voice channel full duplex technique with line of sight, which uses a laser beam as a carrier wave in free space. The constructed system consists of a tranciever (transmitter and receiver ) for both sides. The transmitter part includes a laser source and other transmitter accessories as well as a receiver component. Pulse code modulation (PCM) technique has been used to transmit voice signal. High quality sound communication link for a distance reaching about 1300m is achieved with signal to noise ratio (S/N) equal to 21.1 d

تم في هذا البحث تصميم وبناء منظومة اتصالات ضوئية رقمية لنقل قناتين صوتية بأتجاهين متعاكسين بوقت واحد بتقنية الإرسال الآني مع تأمين خط النظر تعمل باستخدام أشعة الليزر كوسط ناقل للمعلومات في الفضاء الحر.ان بناء منظومة الاتصالات الضوئية تضمنت بوردين الكترونيين يحتوي كل بورد على وحدة ارسال واستقبال ، وباستخدام تقنية التضمين النبضي المشفر PCM لنقل قناة صوتية يتراوح ترددها بين 0.3 – 4 kHz ومعدل نقل البيانات الرقمية لهذه المنظومة 100kbps باستخدام تقنية توشير اللاعودة الى الصفر لقد تم تحقيق حلقة اتصال صوتية بوقت واحد وبوضوح عالي الدقة وعلى مديات وصلت الى مسافة 1300 m وتم حساب نسبة الإشارة إلى الضوضاء S/N فوجد انها تساوي (21.1dB) .


Article
Implementation & Measurement of the Performance 802.11b WLAN System Using Radio Frequency

Author: Anwer A. Mohammed
Journal: Al-Fatih journal مجلة الفتح ISSN: 87521996 Year: 2005 Volume: 1 Issue: 24 Pages: 34-44
Publisher: Diyala University جامعة ديالى

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Abstract

This paper presents an empirical performance analysis of a wireless network of 802.11b technology. The system provides communications to fixed, portable and mobile users and offer substantial flexibility to both end-users and service providers. The basic purpose of this paper is to analyze the performance of a designed wireless network capable of sending high data rates by measurement of the power transmitted as a function of distance and calculation of the signal to noise ratio at the Rx input for different distances. In this paper we studied the behavior of transmitted signals in free space for 400m distance between two buildings, the experimental wireless data network is designed and tested for this purpose, the measurements shows the wireless coverage and throughput patterns for static and mobile users. We have discovered which channel parameters have the most significant impact on performance in actual local environment. The application used to perform all the experiments is typical of common applications that would use these protocols and network technologies.


Article
Model measure the effectiveness of the tax system in IraqFor the period 1980-2009
نموذج قياس فاعلية النظام الضريبي في العراق

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Abstract


Article
Design & Implementation of a Mobile Phone Charging System Based on Solar Energy Harvesting

Author: Qutaiba I. Ali,
Journal: Iraqi Journal for Electrical And Electronic Engineering المجلة العراقية للهندسة الكهربائية والالكترونية ISSN: 18145892 Year: 2011 Volume: 7 Issue: 1 Pages: 69-72
Publisher: Basrah University جامعة البصرة

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Abstract

The ability to harvest energy from the environmentrepresents an important technology area that promises toeliminate wires and battery maintenance for many importantapplications and permits deploying self powered devices. Thispaper suggests the use of a solar energy harvester to chargemobile phone devices. In the beginning, a comprehensiveoverview to the energy harvesting concept and technologies ispresented. Then the design procedure of our energy harvesterwas detailed. Our prototype solar energy harvester proves itsefficiency to charge the aimed batteries under sunlight or anindoor artificial light

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