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Article
Solar cells based on natural dyes prepared using anatase phase titanium dioxide
الخلايا الشمسية المنشأة على الأصباغ الطبيعية المعدة باستخدام ثاني أكسيد التيتانيوم في طور الانتس

Author: Falah H. Ali فلاح حسن علي
Journal: Iraqi Journal of Physics المجلة العراقية للفيزياء ISSN: 20704003 Year: 2018 Volume: 16 Issue: 39 Pages: 28-32
Publisher: Baghdad University جامعة بغداد

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Abstract

Natural dye sensitized solar cell was prepared using strawberry and pomegranate dyes with anatase nanocrystalline titanium dioxide powder. A study of the optical properties of the two dyes, involving the absorption spectrum was determined in the visible region. I-V characteristics under illumination were performed. The results showed that the two prepared dye sensitized solar cells have acceptable values efficiency about (0.94 with Fill factor (45)) and (0.74 with Fill factor (44)) for strawberry and pomegranate dyes, respectively.

في هذا العمل تم تحضير الخلايا الشمسية الحساسة للصبغة الطبيعية عن طريق استخدام أصباغ الفراولة والرمان مع مسحوق النانو كريستال طور الانتس لثاني اوكسيد التيتانيوم. من خلال دراسة الخواص البصرية للصبغتين، تم تحديد طيف امتصاصهما في المنطقة المرئية. وأظهرت خصائص I-V تحت الإضاءة أن الخلايا الشمسية المحضرة بالصبغتين لهما كفاءة قيم مقبولة (%0.94 مع عامل الملئ (45)) و (%0.74 مع عامل الملئ (44)) لأصباغ الفراولة والرمان على التوالي.

Keywords

Natural dye --- low cost --- DSSC --- efficiency.


Article
Activity-Based Costing System and its Role in Decisions Making in Iraqi industrial companies: A Field Study

Author: Lubna Hashem Noman
Journal: Al Malweah for Archaeological and Historical studies مجلة الملوية للدراسات الآثارية والتاريخية ISSN: 24131326 Year: 2018 Volume: 5 Issue: 11 Pages: 323-338
Publisher: University of Samarra جامعة سامراء

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Abstract

The aim of this study is to examine the relationship between the Activity Based Costing (ABC) and the Decisions Making in Iraqi Industrial Companies. In order to conduct the study, a questionnaire was designed and addressed to Financial Managers, Cost managers, Cost Accountants, Financial Accountants, and Auditors in Iraqi industrial companies. Five-point likert scales were used for measurement and one-sample t-test is applied for testing the hypothesis of the study, one of the most important results of the study that the (ABC) information is an excellent source that underpins strategic and operational decisions.


Article
Cost and Time Risk Management in Construction Projects

Author: Yousif Salam Saeed
Journal: Tikrit Journal of Engineering Sciences مجلة تكريت للعلوم الهندسية ISSN: 1813162X 23127589 Year: 2018 Volume: 25 Issue: 1 Pages: 42-48
Publisher: Tikrit University جامعة تكريت

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Abstract

Identifying and evaluating the business risk (Cost and time overruns) management in construction projects to control and minimize such risk is the aim of this research. In diverse construction site, qualified professional workings are asked through an online questionnaire to collect tremendous diverse thoughts to compare between them. The questionnaire developed the research and collected more sensitive/accurate and reliable data about construction business risk management. The first step in this research is to attain worthy information about business risk management in term of cost and time overruns from previous related studies. A theoretical background about management of business risk is provided by the review of these studies that led to the design of the questionnaire questions. This paper concluded that poor business performance, such as time delays and cost overruns, are common in construction projects. Poor business performances can be significantly reduced by providing adequate construction planning at the beginning of the project, accurate in estimation, preventing changes in projects during construction, improving contract management and improving communication between construction parties.


Article

Authors: Hatem Asal Gza --- Noor Qassim Sabri
Journal: Al-Qadisiyah Journal for Engineering Sciences مجلة القادسية للعلوم الهندسية ISSN: 19984456 Year: 2018 Issue: 2 Pages: 229-245
Publisher: Al-Qadisiyah University جامعة القادسية

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Abstract

Natural materials that are readily available in large amounts in nature and easily accessible may be used as low cost additives. The aim of this study is to measure the susceptibility of these locally available materials, conocarpus plant, to improve the quality of wastewater discharged from textile industry.In addition to conocarpus- without chemically treated, conocarpus- chemically treated, carbonized conocarpus and activated carbon were used as adsorbents in order to make a comparison, and to test which one of the four types give the best efficiency for removing dye. The ability of adsorbents to adsorb dye was studied using continuous system; studied parameters were effect of flow rate, bed depth, and initial concentration. The experimental results showed that maximum removal efficiency of conocarpus - without chemically treated was found to be 90% after 75 min at flow rate 20 l/h, pH value 3 , bed depth 5cm and initial concentration 40 mg/l. The maximum removal efficiency for conocarpus- chemically treated was up to 83.75% after 15 min at flow rate 10 l/h, pH value 3, bed depth 10 cm and initial dye concentration 40 mg/l. The maximum removal efficiency for carbonized conocarpus was up to 99.67% after 15 min at flow rate 10 l/h, pH value 3, bed depth 10 cm and initial dye concentration 40 mg/l. For activated carbon the maximum removal efficiency was found to be 99.75% after 15 min at flow rate 10 l/h, pH value 3, bed depth 10cm and initial dye concentration 40 mg/l.


Article
REMOVAL OF TERASIL BLUE DYE FROM SYNTHETIC WASTEWATER USING LOW COST AGRO-BASED ADSORBENTS

Authors: Hatem Asal Gzar --- Noor Qassim Sabri
Journal: Al-Qadisiyah Journal for Engineering Sciences مجلة القادسية للعلوم الهندسية ISSN: 19984456 Year: 2018 Volume: 11 Issue: 2 Pages: 246-255
Publisher: Al-Qadisiyah University جامعة القادسية

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Abstract

Natural materials that are readily available in large amounts in nature and easily accessible may be used as low cost additives. The aim of this study is to measure the susceptibility of these locally available materials, conocarpus plant, to improve the quality of wastewater discharged from textile industry. In addition to conocarpus plant, carbonized conocarpus and activated carbon were used as adsorbents in order to make a comparison, and to test which one of the three types give the best efficiency for removing dye. The ability of adsorbents to adsorb dye was studied using batch system; studied parameters were effect of pH, dose of adsorbents, time, and agitation speed. The experimental results showed that the maximum removal efficiency of conocarpus was found to be 87.5% at 50 rpm mixing speed, pH value 3 , mixing time 120 min and the dose of adsorbent was 0.25 g. The maximum removal efficiency for carbonized conocarpus was up to 98.7% at 150 rpm mixing speed, pH value 3 , mixing time was equal to 7 hours and the dose of sorbent was 1.25 g. For activated carbon the maximum removal efficiency was found to be 99% at mixing speed of 200 rpm, pH value 3 or 11, mixing time was equal to 7 hours and the dose of the sorbent was 1.25 g. The above removal efficiencies were obtained at temperature 20 °C.


Article
Developing of Reliability-Centered Maintenance Methodology in Second Power Plant of South Baghdad

Authors: Amjad B. Adulghafour --- Ammar I. Abdulwahed
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2018 Volume: 36 Issue: 8 Part (A) Engineering Pages: 842-852
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

Electric equipments of power station must be operated in the state of high reliability with its responsibility in the seamless power supply. Maintenance is one of the important and most costly phases in the lifecycle of any power generation systems, to improve maintenance management and system reliability and maintain the continuity of work of the system. Reliability-Centered Maintenance (RCM) is one of the most recent maintenance techniques. In this research, an enhanced RCM methodology based on quantitative relationships implemented at system component level and the overall system reliability was applied to identify the distribution components that are critical to system reliability. Only unit one of the Second Power Plant of South Baghdad were selected as a case study in this research application. The major contribution of the study is to create a maintenance plan through applying statistical, historical data to generate a failure probability distribution model by using the combined methods of Failure Mode of Effects and Criticality Analysis (FMECA) and Fault Tree Analysis (FTA). Evaluation criteria and matrixes of criticality are used to evaluate the criticality level of failure modes. The overall approach developed offers a cost-effective model, which can be applied prior to testing and inspection procedures during the RCM application. The results obtained from this case study show that the application of proposed RCM methodology based on preventive maintenance planning will decrease the total cost value of maintenance about 463469.85 $. That Indicates saving about 59% of the total downtime cost compared with current maintenance. As well as Proposed maintenance program reduce the required time to repair the plant components annually at a rate 6 day so that represent that the labor cost will minimized about 6424 $.


Article
Building Information Modeling (BIM) as Economical and Properties Assessment Tool for Building Units Alternatives Made with Lightweight Foamed Concrete

Authors: Abbas M. Abd عباس مهدي عبد --- Dunya S. Jarullah
Journal: DIYALA JOURNAL OF ENGINEERING SCIENCES مجلة ديالى للعلوم الهندسية ISSN: 19998716/26166909 Year: 2018 Volume: 11 Issue: 2 Pages: 33-41
Publisher: Diyala University جامعة ديالى

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Abstract

Lightweight foamed concrete brick is new construction materials. It gives a prospective solution to building construction industry, this research aims to study the cost, dead loads, environmental issues and energy consumption from using lightweight foam concrete bricks as construction materials by utilizing building information modeling technique. The results obtained from this modelling proved that the cost of brick work using lightweight foamed concrete units of grade A (2000 kg/m3) and B (1800 kg/m3) is higher by (19.4% and 11.9%) respectively than the activity cost using traditional fired clay bricks. For grade C (1600 kg/m3) that cost was very close to fired clay bricks (+2.9%). while the construction of brick work using light weight foamed concrete units of grade D (1400 kg/m3) and E (1200 kg/m3) was lower by (8% and 18.6%) than fired clay bricks. Besides that, the dead load generated by building units was decreased by (7.7-38.5%) for grade (B, C, D, E) than the load of fired clay bricks, while the load generated from used lightweight foam concrete bricks grade is very closed to fired clay bricks (+2.5%). There was a reduction in energy consumption by the rate of (4.1-62.2%) for heating and (9.8-73.4%) for cooling as wall sharing in energy consumption. Environmental analysis showed sustainable potential so that the production of lightweight foamed concrete units reduces CO2 emission by (46.5-67.9%) compared with the fired clay bricks. Finally; it can be concluded that building units produced in this research with LWFC, characterized with properties can efficiently compete the fired clay bricks.


Article
Flexible Genetic Algorithm Based Optimal Power Flow of Power Systems
الخوارزمية الجينية المرنة المستخدمة في سريان القدرة المثالي في انظمة القدرة

Authors: Hassan Abdullah Kubba حسن عبدالله كبة --- Mounir Thamer Esmieel منير ثامر اسماعيل
Journal: Journal of Engineering مجلة الهندسة ISSN: 17264073 25203339 Year: 2018 Volume: 24 Issue: 3 Pages: 84-96
Publisher: Baghdad University جامعة بغداد

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Abstract

Nowadays, the power plant is changing the power industry from a centralized and vertically integrated form into regional, competitive and functionally separate units. This is done with the future aims of increasing efficiency by better management and better employment of existing equipment and lower price of electricity to all types of customers while retaining a reliable system. This research is aimed to solve the optimal power flow (OPF) problem. The OPF is used to minimize the total generations fuel cost function. Optimal power flow may be single objective or multi objective function. In this thesis, an attempt is made to minimize the objective function with keeping the voltages magnitudes of all load buses, real output power of each generator bus and reactive power of each generator bus within their limits. The proposed method in this thesis is the Flexible Continuous Genetic Algorithm or in other words the Flexible Real-Coded Genetic Algorithm (RCGA) using the efficient GA's operators such as Rank Assignment (Weighted) Roulette Wheel Selection, Blending Method Recombination operator and Mutation Operator as well as Multi-Objective Minimization technique (MOM). This method has been tested and checked on the IEEE 30 buses test system and implemented on the 35-bus Super Iraqi National Grid (SING) system (400 KV). The results of OPF problem using IEEE 30 buses typical system has been compared with other researches.

الهدف من دراسة سريان القدرة المثاليOPF)) هو للتقليل في دالة الهدف (كلفة الانتاج). سريان القدرة المثالي قد يكون احادي دالة الهدف او متعدد الدوال. في هذا الاطروحة تم تقليل كلفة الانتاج في توليد القدرة الحقيقية مع الحفاظ على قيم الجهد والقدرة الخارجة من كل محطة توليدية ضمن الحدود المسموح بها وابقاء النظام ضمن شروط الامان للنظام. هناك عدة طرق لحل مشاكل سريان القدرة المثالي: التقليدية وطرق الذكاء الاصطناعي. الطرق التقليدية تعتمد على خواص المعادلات اما طرق الذكاء الاصطناعي فانها فقط تعتمد على دالة الهدف. الخوارزمية المقترحة لهذه الاطروحة هي الخوارزمية الجينية المرنة (الحقيقية) بعد فحصها وتطبيقها على نظام ال٣٠ عقدة ل IEEE تم تطبيقها على نظام ال ٣٥ عقدة للشبكة الوطنية العراقية ذات الجهد الفائق. تم مقارنة نتائج نظام ال٣٠ عقدة مع بحوث اخرى ذات نفس الصلة. في هذه الاطروحة المتغيرات المسيطرة هي القدرة الخارجة من كل عقدة توليدية ما عدا عقدة المرجع (slack bus) وهي محددات المساواة اما محددات اللامساواة فهي الحدود الدنيا والعليا للقدرة الفعالة والغير فعالة لكل عقدة توليدية والجهد لكل العقد في النظام. البيانات الحقيقة للشبكة العراقية قد تم الحصول عيها من وزارة الكهرباء.

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