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Experimental Evaluation of Thermal Performance of Solar Assisted Vapor Compression Heat Pump
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The thermal performance of indirect expansion solar assisted heat pump, IX-SAHP, was investigated experimentally under Iraqi climate. An Indirect-Solar Assisted Heat Pump system was designed, built, instrumented and tested. Experimental tests were conducted by varying the controlling parameters to investigate their effects on the thermal performance of the IX-SAHP such as cooling water flow rate, heating water flow rate, ambient temperature and solar radiation intensity. The investigation covered values of cooling water flow rate of (2, 3, 4, 5 l/min) and heating water flow rate of (2, 3, 4, 5 l/min) under meteorological condition of Baghdad from November 2014 to January 2015.

The results indicated that the performance of the IX-SAHP is not dependent on the heating water flow rate. On the contrary of heating water flow rate, cooling water flow rate has significant effect on the thermal performance of the system. The COP of the heat pump system is decreased with increasing cooling water flow rate. The collector heat gain increase with increasing the solar radiation and ambient temperature, this leads to increase in COP from 2.2 to 2.39 as the ambient temperature and solar radiation increase from 9.9℃ and 268 W/m2 to 14.9 ℃ and 689 W/m2 respectively.

 

 

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Publication Date
Tue Nov 21 2023
Journal Name
Mater Sci: Mater Electron
Pulsed laser deposition of nanostructured CeO2 antireflection coating for silicon solar cell
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Increasing the power conversion efficiency (PCE) of silicon solar cells by improving their junction properties or minimizing light reflection losses remains a major challenge. Extensive studies were carried out in order to develop an effective antireflection coating for monocrystalline solar cells. Here we report on the preparation of a nanostructured cerium oxide thin film by pulsed laser deposition (PLD) as an antireflection coating for silicon solar cell. The structural, optical, and electrical properties of a cerium oxide nanostructure film are investigated as a function of the number of laser pulses. The X-ray diffraction results reveal that the deposited cerium oxide films are crystalline in nature and have a cubic fluorite. The field

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Publication Date
Mon Nov 01 2021
Journal Name
Journal Of Engineering
Performance Evaluation of Pole Placement and Linear Quadratic Regulator Strategies Designed for Mass-Spring-Damper System Based on Simulated Annealing and Ant Colony Optimization
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This paper investigates the performance evaluation of two state feedback controllers, Pole Placement (PP) and Linear Quadratic Regulator (LQR). The two controllers are designed for a Mass-Spring-Damper (MSD) system found in numerous applications to stabilize the MSD system performance and minimize the position tracking error of the system output. The state space model of the MSD system is first developed. Then, two meta-heuristic optimizations, Simulated Annealing (SA) optimization and Ant Colony (AC) optimization are utilized to optimize feedback gains matrix K of the PP and the weighting matrices Q and R of the LQR to make the MSD system reach stabilization and reduce the oscillation of the response. The Matlab softwar

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Publication Date
Tue Feb 26 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Role of Managerial Accounting Information System in Improving the Value Chain and its Impaction Evaluation Performance: دراسة حالة في الشركة العامة لصناعة الزيوت النباتية
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The performance measures and traditional methods used in management accounting is no longer able to provide convenient to evaluate the performance of economic units in the modern manufacturing environment information، and so this information is more important and feasibility must be Mistohat of all the company's activities and functions، and it is a problem Find the inadequacy of information management accounting that contribute to meet the needs of the upper levels of management to cope with the problems resulting from the increased size and complexity of the business، and lack of management accounting information and methods used in the performance evaluation، which reflected negatively on the value chain activities and then on the

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Publication Date
Fri Aug 20 2021
Journal Name
Open Access Macedonian Journal Of Medical Sciences
Autogenous Onlay Graft with Compression Plate for Treatment of Persistent Humeral Shaft Aseptic Non-union with Failed Previous Surgery
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BACKGROUND: The humeral shaft fractures have a good rate of union, despite this fact, still there is a significant rate of nonunion after nonoperative treatment and more often after operative treatment. AIM: The aim of the study is to evaluate the autogenous onlay graft with compression plate for treatment of persistent humeral shaft non-union with failed previous surgery both radiological and functional outcome. MATERIALS AND METHODS: A prospective study on twenty patients having persistent aseptic non-union age between 20 and 60 years old, after failed surgical treatment of fractures humeral shaft in Al-Zahra teaching and Al-Kindy teaching hospitals, while infected nonunion, diabetes mellitus, secondary metastasis, smoking, a

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Publication Date
Mon Jan 01 2024
Journal Name
Baghdad Science Journal
Surface Modification of the Improved Stainless Steel Alloy AISI-304 and the Use of Diffusion Coating and a Study of Its Efficiency in Resistivity Hot Corrosion in an Atmosphere of Sodium Chloride Vapor NaCL and Sodium SulfateNa_2 SO_4
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       This research aims to modify the components of stainless steel alloy by the method of surface engineering through the single diffusion coating technique in order to obtain new alloys with high efficiency in resisting harsh environmental conditions. Steam a mixture of sodium chloride ( ) and sodium sulfate ( ) at a temperature of 900 and then compare it with the base alloy. The results showed that the alloys produced in this way are very efficient. The results showed that the aluminum coating showed high efficiency in resisting oxidation and provided better protection for a longer time compared to the uncoated alloy due to the  oxide crust layer formed with high adhesion as well as the aluminum-rich phases, whether the phase

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Publication Date
Fri Mar 15 2024
Journal Name
Journal Of Baghdad College Of Dentistry
Assessment of the correlation between the tensile and diametrical compression strengths of 3D-printed denture base resin reinforced with ZrO2 nanoparticles
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Background: The mechanical properties of 3D-printed denture base resins are crucial factors for determining the quality and performance of dentures inside a patient’s mouth. Tensile strength and diametral compressive strength are two properties that could play significant roles in assessing the suitability of a material. Although they measure different aspects of material behavior, a conceptual link exists between them in terms of overall material strength and resilience. Aim: This study aims to investigate the correlation between tensile strength and diametral compressive strength after incorporating 2% ZrO2 nanoparticles (NPs) by weight into 3D-printed denture base resin. Methods: A total of 40 specimens (20 dumbbell-shaped and

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Publication Date
Tue Sep 01 2020
Journal Name
Journal Of Engineering
Experimental and Theoretical Determination of Settlement of Shallow Footing on Liquefiable Soil
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A high settlement may take place in shallow footing when resting on liquefiable soil if subjected to earthquake loading. In this study, a series of shaking table tests were carried out for shallow footing resting on sand soil. The input motion is three earthquake loadings (0.05g, 0.1g, and 0.2g). The study includes a reviewing of theoretical equations (available in literatures), which estimating settlement of footings due to earthquake loading, calibration, and verification of these equations with data from the shaking table test for improved soil by grouting and unimproved soil. It is worthy to note that the grouting materials considered in this study are the Bentonite and CKD slurries. A modification to the seismic set

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Publication Date
Tue Jul 02 2019
Journal Name
Fibers
Experimental Investigation of the Behavior of Self-Form Segmental Concrete Masonry Arches
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This research aims to introduce a new technique-off-site and self-form segmental concrete masonry arches fabrication, without the need of construction formwork or centering. The innovative construction method in the current study encompasses two construction materials forms the self-form masonry arches, wedge-shape plain concrete voussoirs, and carbon fiber-reinforced polymer (CFRP) composites. The employment of CFRP fabrics was for two main reasons: bonding the voussoirs and forming the masonry arches. In addition, CFRP proved to be efficient for strengthening the extrados of the arch rings under service loadings. An experimental test was conducted on four sophisticated masonry arch specimens. The research parameters were the Keystone thic

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Publication Date
Thu May 18 2023
Journal Name
Journal Of Engineering
Theoritical and Experimental Investigation of the Dynamical Behaviour of Complex Configuration Rotors
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The present work considers an alternative solution for a complex configuration of rotor discs by applying Galerkin Method. The theoretical model consists of elastic shaft carrying number of discs and supported on number of journal bearings. The equation of motion was discretized to finite degree of freedom in terms of the system generalized coordinates. The various effects of the dynamical forces and moments arising from the bearing, discs and shaft were included. Rayleigh beam model is used for analyzing the shaft while the discs are considered rigid . The validity and convergence of the present analysis was carefully checked by comparing with the Finite Element solution. An example of rotor consists of three different size discs and su

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Publication Date
Wed Jul 01 2020
Journal Name
Iop Conference Series: Materials Science And Engineering
Experimental and Numerical Comparison of Prestressed Perforated Concrete Rafters of Different Configurations
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Abstract<p>This paper demonstrates an experimental and numerical study aimed to compare the influence of openings of different configurations on the flexural behavior of prestressed concrete rafters. The experimental program consisted of testing six simply supported prestressed concrete rafters; 5 rafters are perforated, and the other one is solid as a reference. All rafters were tested under monotonic midpoint load. The variable which has been investigated in this work was the opening’s configuration (quadrilateral or circular) with the same upper and lower chords depths. The results indicate improvement in the beam flexural behavior using the circular openings compared to the quadrilateral o</p> ... Show More
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