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Article
SEIF-ADJIONT OPERATOR OF PERIDYNAMIC MODEL

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Abstract

In this paper, we study a functional analytical framework for a linear peridynamic model of spring system in one dimension,Various properties of the peridynamic operators are examining for general micromodulus,one this properties of peridynamic operator are self-adjont.


Article
EXPERIMENTAL AND MATHEMATICAL EVALUATION OF THE REFRIGERATION SYSTEM PERFORMANCE WITH DIFFERENT AMBIENT TEMPERATURE

Authors: Ahmed Abed Mohammed --- Ali Abas Nasser
Journal: Journal of Engineering and Sustainable Development مجلة الهندسة والتنمية المستدامة ISSN: 25200917 Year: 2017 Volume: 21 Issue: 6 Pages: 1-19
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

The present work includes two main parts. Firstly: the experimental part which takes respect of the effect of changing magnitude of supplied voltage to compressor ,condenser air flow rate and evaporator air flow rate on system performance . The effect of ambient temperature on system performance is also considered .The experimental study has been done on a split air- conditioner with a 1 TR nominal capacity .The experimental results show that, reducing the supplied voltage to compressor by 23% caused the refrigeration capacity and COP)tot to decrease by 7.7% and 5.7% ,respectively and when condenser air flow reduced by 35.8%, cause the refrigeration capacity and COP)tot to decrease by 1.6% and 7.1%, respectively . Also the reduce of the evaporator air flow by 46.7%, the refrigeration capacity and COP)tot decreased by 11.4% and 9.6% ,respectively . Secondly the theoretical part, in which a mathematical model has been developed for the vapor compression refrigeration cycle to predict the system performance under the various ambient temperatures. The mathematical model was performed using Matlab software. The comparison between the mathematical results and experimental results, show that, the maximum deviation of condenser capacity, refrigeration capacity, power input to compressor and COP are 1.75%, 3.2%, 3.34% and 4.84%, respectively.


Article
Mathematical Driving Model of Three Phase, Two Level Inverter by (Method of Interconnected Subsystem)

Author: Mohammed .H. Ali
Journal: Iraqi Journal for Electrical And Electronic Engineering المجلة العراقية للهندسة الكهربائية والالكترونية ISSN: 18145892 Year: 2017 Volume: 13 Issue: 1 Pages: 73-82
Publisher: Basrah University جامعة البصرة

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Abstract

In this paper describe to mathematical analysis for a three-phase, two level inverter designs. As we know the power electronic devices (inverter) to convert the DC power to AC power (controller on output voltage and frequency level). In Industrial applications, the inverters are used for adjustable speed (AC Drives). In this paper, the mathematical analyses for inverter design are done by using Software packages C++ Builder and visual C++ Language. For non- linear distortions described by the load power factor in power system networks. The P.F is reverse proportional with the harmonics distortion. Small P.F means much more of harmonic distortion, and lower power quality for consumers. to improve the P.F, and power quality in this paper the small capacitor installed as part of the rectified the load current has power (30 KW with P.F load 0.8), the fluctuations of the rectified voltage must not greater than +/- 10%.The power factor proportion of the load power, with Modulation coefficient p.u approximately unity. The calculation is achieved with different integrations steps with load power 30KW, 0.8 P.F. all results done Based on model and experimental data..


Article
MATHEMATICAL DRIVING MODEL OF THREE PHASE INDUCTION MOTORS IN STATIONARY COORDINATE FRAME

Authors: Ahmed Ibrahim jaber احمد ابراهيم جابر --- Husham Idan Hussein هشام عيدان حسين
Journal: DIYALA JOURNAL OF ENGINEERING SCIENCES مجلة ديالى للعلوم الهندسية ISSN: 19998716/26166909 Year: 2015 Volume: 8 Issue: 4 Pages: 255-265
Publisher: Diyala University جامعة ديالى

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Abstract

In this paper mathematical analysis for a design three-phase induction motor. Three phase AC induction motors is popular in manufacturing for many reasons. It is quite simple and minimum costs are favorable. It does not have brushes and requires minimum maintenance. In this paper a mathematical development to three-phase AC induction motor by using matrix form. The development applying on model of a real drive of 1.1 kW motor has been achieved. To analysis the axis, three-phase coordinate (A, B, C) to a two axis (β - α) as a (stationary part) representation. Through this drive conversion torque and speed can be controlled easily and control optimization induction motors. MATLAB/ SIMULINK is used to simulate the model of (IM) as tool and for study of characteristics of the motor.


Article
The Behaviors of some Counting Functions of g-primes and g-integers as x goes to Infinity

Authors: Ahmed Amer AL-Quraishi --- Faez A. AL-Maamori
Journal: Journal of University of Babylon مجلة جامعة بابل ISSN: 19920652 23128135 Year: 2018 Volume: 26 Issue: 1 Pages: 68-76
Publisher: Babylon University جامعة بابل

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Abstract

In this article we focus on the behaviors of the generalised counting function of primes 〖 Π〗_P(x) and the counting function of integers N_P(x) as well as the link between them as x ⟶ ∞ . Here the Riemann zeta function ζ_P(s) ( = ∑_n▒n^(-s) , R(s) > 1 ) play an important role as a link between 〖 Π〗_P(x) and N_P(x) . This work will go through the method ( not in details ) adapted by Balanzario [Balanzario , 1998] and later generalised by AL- Maamori [AL- Maamori , 2013 ] . Finally we shall draw a diagram in order to determine the relation between α and β , (where α and β are the power of the error terms H1(x) , H2(x) of 〖 Π〗_P(x) and N_P(x) respectively) . The aim of this work is to analysis the behaviour of 〖 Π〗_P(x) and N_P(x) as x ⟶ ∞ . Note that : ʺ It’s a beneficial to point out that our effort in this paper is not to exchange the values of some functions of Balanzarioʹs method . Since , changing any small value of one of the functions of Balanzarioʹs method may be leads to loss the aim of the work ʺ . Therefore , in this article we show the ability of changing the values of some functions and in which places in the proof we should sort out .

في هذا البحث نركز على تصرفات الدوال الحسابية الموسعة للأعداد الاولية 〖 Π〗_P(x) وللأعداد الصحيحة N_P(x) وكذلك الرابط بينهما عندما x ← ∞ . هنا دالة ريمان زيتا ζ_P(s) ( = ∑_n▒n^(-s) , R(s) > 1 ), تلعب دورا مهما كرابط بين 〖 Π〗_P(x) و N_P(x) . هذا العمل سيتم من خلال سلوك طريقة العالم بلنزاريو ]بلنزاريو، 1998 [ ليست بالتفاصيل والتي عممت من خلال المعموري ] المعموري ، 2013 [ . بالنهاية سوف نرسم مخططا يحدد العلاقة بين α و β ( حيث α و β هما القوى للحدود الخطأ H1(x) و H2(x) من 〖 Π〗_P(x) و N_P(x) على التوالي . الغرض من هذا البحث هو تحليل تصرفات 〖 Π〗_P(x) و N_P(x) عندما x ← ∞ . ملاحظة : من المهم والنافع الاشارة بان جهدنا في هذا البحث ليست تغيير بعض قيم الدوال التي استخدمت في طريقة بلنزاريو حيث ان تغيير اي قيمة مهما كانت صغيرة لإحدى دوال طريقة بلنزاريو ربما تقودنا الى خسارة هدف الموضوع بأكمله . ولهذا نبين ايضا قابلية التغيير المسموح بها في قيم بعض الدوال . كذلك سوف نختم البحث بفتح باب لعمل مستقبلي .

Scientifie journal Of physical education
مجلة المثنى لعلوم التربية الرياضية

ISSN: 22266631
Publisher: Al-Muthanna University جامعة المثنى
Subject: Education (General)

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Abstract

Scientific journal League semi-annual specialized court issued by the Faculty of Physical Education / University of Muthanna by two numbers each year was the first issue in the beginning of 2012 and the magazine aims to spread scientific culture and the development of the sporting side through scientific research discreet, which are subject to the calendar scientific sober by relevant experts before publication.

مجلة علمية دوري نصف سنوي محكمة متخصصة تصدر عن كلية التربية الرياضية/جامعة المثنى بواقع عددين كل سنة تم اصدار العدد الاول في بداية عام 2012 وتهدف المجلة الى نشر الثقافة العلمية وتطوير الجانب الرياضي من خلال البحوث العلمية الرصينة التي تخضع للتقويم العلمي الرصين من قبل خبراء مختصين قبل النشر.

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