The distribution of chilled water flow rate in terminal unit is a major factor used to evaluate the performance of central air conditioning unit. In this work, a theoretical chilled water distribution in the terminal units has been studied to predict the optimum heat performance of terminal unit. The central Air-conditioning unit model consists of cooling/ heating coil (three units), chilled water source (chiller), three-way and two-way valve with bypass, piping network, and pump. The term of optimization in terminal unit ingredient has two categories, the first is the uniform of the water flow rate representing in statically permanents standard deviation (minimum value) and the second category is the maximum heat transfer rate from all terminal units. The hydraulic and energy equations governing the performance of unit solved with the aid of FORTRAN code with considering the following parameters: total water flow rate, chilled water supply temperature, and variable valve opening. It was found that the optimum solution of three-way valve case at 8°C water supply temperature, 0.12 kg/s total water flow rate and valve opening order (valve 1: 100%, valve 2: 100% and valve 3: 75%) with total heat rate (987.92 Watt) and standard deviation (1.181E-3). Also, for the two-way valve case the results showed that the optimum condition at 8°C water supply temperature, 0.12 kg/s total water flow rate and valve opening order (valve 1: 75%, valve 2: 75% and valve 3: 50%) with total heat rate and standard deviation (717Watt) and (5.69E-4) respectively.
Abstract
In this work, diabetic glucose concentration level control under disturbing meal has been controlled using two set of advanced controllers. The first set is sliding mode controllers (classical and integral) and the second set is represented by optimal LQR controllers (classical and Min-, ax). Due to their characteristic features of disturbance rejection, both integral sliding mode controller and LQR Minmax controller are dedicated here for comparison. The Bergman minimal mathematical model was used to represent the dynamic behavior of a diabetic patient’s blood glucose concentration to the insulin injection. Simulations based on Matlab/Simulink, were performed to verify the performance of each controll
... Show MoreBackground: (ABO) Blood type have an effect on general health including oral health as salivary physicochemical characteristics differ among different type of blood and as consequence these affect the severity of dental caries. The aim of the present study is an assessment of the prevalence of caries experience among different blood type in relation to salivary physicochemical characteristic. Materials and Methods: Two hundred and fifty females' college students in Al-Qadisyia University aged 18 years old were selected on random basis; they were divided to four groups according to their blood type, Dental experience was diagnosed and recorded according to DMFs (Mülemman, 1976) Index, this allows recording decayed lesion by severity. A su
... Show MorePurpose - This study relies on the descriptive and analytical approach through collecting and analyzing the necessary data, as this approach focuses on polling the opinions of the research sample and its directions, and aims to develop a model that studies the relationship between knowledge creation and organizational ambidexterity in Iraqi private banks and verifying its validity experimentally.
Design / Methodology / Introduction - A survey was conducted through a questionnaire form to collect data from a sample of (113) managers in private commercial banks. In addition, this study used the AMOS program and the ready-to-use statistical program package (SPSS V.25) to test the proposed hypotheses of the t
... Show Moreشهد العصر الحالي سرعة فائقة في انتاج وسائل الاتصال لاسيما في حقل الاتصال الاليكتروني وتوضح ذلك عبر الاندماج بين ظاهرة الكم الهائل من المعلومات وتعدد الوسائل الاتصالية وذلك لتحقيق الهدف المنشود لبث الرسالة الاتصالية الا وهو التفاعل من اجل التأثير في الفرد ومن ثم المجتمع ككل , فيما اضحت العلاقات العامة احد العوامل المؤثرة في عملية التغيير الاجتماعي بما تستند اليه من ممارسات تضعها في اطار الوظائف المجتمعية ال
... Show MoreThe audit committees are considered to be one of the most important committees because of the role they play in supervising and monitoring the process of formation of the financial statements and correction of the internal supervising system also strengthening the independency of the internal and external audit. Matters which increases the efficiency and integrity of the financial statements which reflects positively on competence of board of directors and then enhance the position of the company through increasing the trust of the users of the financial statement within the company.
Therefore, this research deals with the evaluation of the performance of the audit committees in Iraqi banks according to the local rules and
... Show Moreيهدف البحث الى قياس مدى التطبيق والتبني للقيادة الملهمة في المنظمات العامة، وقد اشتقت مشكلة البحث النظرية من وجود فجوة معرفية وذلك لقلة الدراسات والبحوث التي تناولت متغير البحث بأبعاده (الرؤية المستقبلية، الثقة بالنفس، تمكين العاملين، ادارة التغيير)، واعتمد البحث المنهج التحليلي عن طريق استعمال الاستبانة في المنظمة التي تم اختيارها وذلك لكونها تعد من المنظمات الاساسية في تقديم الخدمات التعليمية المهمة في
... Show MoreSeen in Iraq that the volume of insurance activity in the case of a clear deterioration and a sharp decline in demand for life insurance, because of reluctance by senior members of the Iraqi society on the demand for life insurance. The study was descriptive approach in identifying and addressing variables, namely the (perception of risk need of the individual trends in personal income of the individual insurance awareness of the individual customs and traditions of communal religious belief of the individual age and sex of the individual methods promotional company competitive alternatives to the insurance service life inflation rate service life insurance) indepen
... Show MoreExamination is a form of tax audits which have been done by tax examiner rests with the General Commission for Taxes is responsible for determining the extent to which the amounts subject to tax provided by the holders of admissions with the laws and regulations, taxes. So the tax-examination is the major means of tax administration to make sure the fact that tax revenues generated from the imposition of taxes different kinds of direct and indirect search result, the importance of the role played by the (Department of Control and Internal Audit / Audit Division in charge) in charge of auditing the accounts, which may be Maclvoha clung to their accounts and access to the tax base acceptable to the expensive and fin
... Show Moreالمستخلص تهدؾ الدراسة الى ل اٌس مدى التطب كٌ والتبن للم اٌدة ال مٌظة ف المنظمات العامة ولد اشتمت مشكلة الدراسة النظر ةٌ من وجود فجوه معرف ةٌ وذلن لملة الدراسات والبحوث الت تناولت متؽ رٌ الدراسة بأبعاده )الرؤ ةٌ المح طٌ ةٌ, التمك نٌ, الشبكات ب نٌ اعضاء الفر قٌ, الترك زٌ, الم لٌ للتعامل مع حالات عدم التأكد( اعتمدت الدراسة منهج دراسة الحالة عن طر كٌ استعمال استمارة الفحص ف المنظمة الت تم اخت اٌرها دائرة العمل والتدر ب
... Show Moreهدف البحث الى تعرف :
1- مستوى الثقافة التنظيمية لرؤساء الأقسام العلمية في كليات جامعة بغداد.
2- الأهمية النسبية لأبعاد الثقافة التنظيمية لرؤساء الاقسام العلمية في كليات جامعة بغداد.
بلغت العينة (380) تدريسي وتدريسية من الأقسام العلمية في كليات جامعة بغداد المتمثلة بـ (كلية الهندسة، كلية العلوم، كلية الإعلام، وكلية التربية للبنات)، اعتمدت الاستبانة أداة لتحقيق أه
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