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Thermal Efficiency for Passive Solar Chimney with and Without Heat Storage material
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In this study, a different design of passive air Solar Chimney(SC)was tested by installing it in the south wall of insulated test room in Baghdad city. The SC was designed from vertical and inclined parts connected serially together, the vertical SC (first part) has a single pass and Thermal Energy Storage Box Collector (TESB (refined paraffin wax as Phase Change Material(PCM)-Copper Foam Matrix(CFM))), while the inclined SC was designed in single pass, double passes and double pass with TESB (semi refined paraffin wax with copper foam matrix) with selective working angle ((30o, 45o and 60o). A computational model was employed and solved by Finite Volume Method (FVM) to simulate the air induced through the test room by SC effect. The governing equation of Computational Fluid Dynamic (CFD) model was developed by the effective heat capacity method equation to describe the heat storage and release from PCM-CFM. Practical and computational Results referred to increase in thermal conductivity of the paraffin wax that supported by CFM than 10 times, while the ventilation effect is still active for hours after sun set amount. The maximum ventilation mass flow rate with TESB collector was 36.651 kg/hr., when the overall discharge coefficient equals 0.371. Also, the experimental results referred to the best working angle range 45~60o, while the highest approaching temperature (between air and collector) was appeared for the double passes flat plate collector. Results gave higher heat storage efficiency 47% when the maximum solar radiation 780 W/m2 at 12.00 pm, and the energy summation through duration of charging time was 18460 kJ. Double passes SC at 60o angle presented the highest efficiency with value approaching to 73%, while TESB collector efficiency depicted highest efficiency value 70% at 12:00 pm.

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Publication Date
Sat Feb 27 2021
Journal Name
Iraqi Journal Of Science
Statistical Fluctuations of Energy Spectra in the Isobar A = 68 Nuclei
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Statistical fluctuations of nuclear energy spectra for the isobar A = 68 were examined by means of the random matrix theory together with the nuclear shell model. The isobar A = 68 nuclei are suggested to consist of an inert core of 56Ni with 12 nucleons in f5p-space (2p3/2, 1f5/2 and 2p1/2 orbitals). The nuclear excitation energies, required by this work, were obtained through performing f5p-shell model calculations using the isospin formalism f5pvh interaction with realistic single particle energies. All calculations of the present study were conducted using the OXBASH code. The calculated level densities were found to have a Gaussian shape. The distributions of level spacing P(s) an

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Publication Date
Fri Nov 24 2017
Journal Name
Journal Of Engineering
A New Analytic Method to Tune a Fractional Order PID Controller
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This paper proposes a new method to tune a fractional order PID controller. This method utilizes both the analytic and numeric approach to determine the controller parameters. The control design specifications that must be achieved by the control system are gain crossover frequency, phase margin, and peak magnitude at the resonant frequency, where the latter is a new design specification suggested by this paper. These specifications results in three equations in five unknown variables. Assuming that certain relations exist between two variables and discretizing one of them, a performance index can be evaluated and the optimal controller parameters that minimize this performance index are selected. As a case study, a thir

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Publication Date
Sat Sep 30 2023
Journal Name
Iraqi Journal Of Science
Towards Solving Fractional Order Delay Variational Problems Using Euler Polynomial Operational Matrices
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     In this paper, we introduce an approximate method for solving fractional order delay variational problems using fractional Euler polynomials operational matrices. For this purpose, the operational matrices of fractional integrals and derivatives are designed for Euler polynomials. Furthermore, the delay term in the considered functional is also decomposed in terms of the operational matrix of the fractional Euler polynomials. It is applied and substituted together with the other matrices of the fractional integral and derivative into the suggested functional. The main equations are then reduced to a system of algebraic equations. Therefore, the desired solution to the original variational problem is obtained by solving the resul

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Publication Date
Tue Nov 01 2016
Journal Name
International Journal Of Pharmaceutical Sciences Review And Research
A study on some variables affecting the preparation of ethyl cellulose based floating microspheres of lafutidine
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Lafutidine (LAF) a newly developed histamine H2-receptor antagonist with absorption window makes it a good candidate to be prepared as floating drug delivery system. The current study involves formulation and in- Vitro evaluation of lafutidine as floating microspheres. Different formulation variables that affect the physicochemical properties of the prepared microspheres besides to the drug release behavior were investigated. Fourteen formulas were prepared by emulsion (o/w) solvent evaporation method using Ethyl cellulose (EC) as the polymeric matrix and tween 80 (TW80) as an emulsifying agent. The prepared formulas were evaluated for their percentage buoyancy (%), Percentage yield (%) and Entrapment efficiency (EE %). The results obt

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Publication Date
Thu May 14 2020
Journal Name
Journal Of Planner And Development
“The role of parametric approach in design highest climatic performance buildings: local housing design patterns as a sample”
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In light of increasing demand for energy consumption due to life complexity and its requirements, which reflected on architecture in type and size, Environmental challenges have emerged in the need to reduce emissions and power consumption within the construction sector. Which urged designers to improve the environmental performance of buildings by adopting new design approaches, Invest digital technology to facilitate design decision-making, in short time, effort and cost. Which doesn’t stop at the limits of acceptable efficiency, but extends to the level of (the highest performance), which doesn’t provide by traditional approaches that adopted by researchers and local institutions in their studies and architectural practices, limit

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Publication Date
Sun Apr 30 2023
Journal Name
Iraqi Journal Of Science
Stabilizability of Riccati Matrix Fractional Delay Differential Equation
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In this article, the backstepping control scheme is proposed to stabilize the fractional order Riccati matrix differential equation with retarded arguments in which the fractional derivative is presented using Caputo's definition of fractional derivative. The results are established using Mittag-Leffler stability. The fractional Lyapunov function is defined at each stage and the negativity of an overall fractional Lyapunov function is ensured by the proper selection of the control law. Numerical simulation has been used to demonstrate the effectiveness of the proposed control scheme for stabilizing such type of Riccati matrix differential equations.

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Publication Date
Thu Jun 01 2023
Journal Name
Journal Of Engineering
Fault Location of Doukan-Erbil 132kv Double Transmission Lines Using Artificial Neural Network ANN
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Transmission lines are generally subjected to faults, so it is advantageous to determine these faults as quickly as possible. This study uses an Artificial Neural Network technique to locate a fault as soon as it happens on the Doukan-Erbil of 132kv double Transmission lines network. CYME 7.1-Programming/Simulink utilized simulation to model the suggested network. A multilayer perceptron feed-forward artificial neural network with a back propagation learning algorithm is used for the intelligence locator's training, testing, assessment, and validation. Voltages and currents were applied as inputs during the neural network's training. The pre-fault and post-fault values determined the scaled values. The neural network's p

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Publication Date
Wed Oct 31 2018
Journal Name
Iraqi Journal Of Science
Structural subsurface model of Samawa-Diwan area (south of Iraq)
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Seismic instantaneous phase attribute was applied for conventional seismic interpretation (structural interpretation) on 3D seismic cube of 1914.72km² of Samawa-Diwan area, located in the south part of Iraq within Muthna governorate. Instantaneous phase section is very important to detect structural and stratigraphic features. Six reflectors represent Upper Jurassic and Cretaceous formations were defined from synthetic seismogram of wells in study area, then picked over seismic cube. Fault boundaries maps for each horizon were drawn depending on horizon contacts then fault planes were constructed. Finally, a 3D structural model was constructed in time domain, then converted to depth domain by using 3D average velocity model. Structurall

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Publication Date
Sun Aug 30 2020
Journal Name
Journal Of Economics And Administrative Sciences
مقترح اسلوب IRWs الحصين لتقدير أنموذج الانحدار المقسم لحركة حمولة قاع نهر دجلة ونقطة التغيير لكمية تصريف المياه عند مدينة بغداد
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              يتكون الانحدار المقسم من عدة أقسام تفصل بينها نقاط انتماء مختلفة، فتظهر حالة عدم التجانس الناشئة من عملية فصل الأقسام ضمن عينة البحث. ويهتم هذا البحث في تقدير موقع نقطة التغيير بين الأقسام وتقدير معلمات الأنموذج، واقتراح طريقة تقدير حصينة ومقارنتها مع بعض الطرائق المستعملة في الانحدار الخطي المقسم. وقد تم استعمال أحد الطرائق التقليدية (طريقة Muggeo) لإيجاد مقدرات الإمكان الأعظم بالأسلوب الت

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Publication Date
Wed Jul 14 2021
Journal Name
The Open Civil Engineering Journal
Producing Sustainable Concrete using Nano Recycled Glass
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Background:

Many tools and techniques have been recently adopted to develop construction materials that are less harmful and friendlier to the environment. New products can be achieved through the recycling of waste material. Thus, this study aims to use recycled glass bottles as sustainable materials.

Objective:

Our challenge is to use nano glass powder by the addition or replacement of the weight of the cement for producing concrete with enhanced strength.

Methods:

A nano recycled glass p

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