The design, construction and investigation of experimental study of two compound parabolic concentrators (CPCs) with tubular absorber have been presented. The performance of CPCs have been evaluated by using outdoor experimental measurements including the instantaneous thermal efficiency. The two CPCs are tested instantly by holding them on a common structure. Many tests are conducted in the present work by truncating one of them in three different levels. For each truncation the acceptance half angle (θc) was changed. Geometrically, the acceptance half angle for standard CPC is (26o). For the truncation levels for the other CPC 1, 2 and 3 the acceptance half angle were 20o, 26o and 59o, consequently. A significant difference between the instantaneous thermal efficiency of 3.86× CPC (θc=20o) and 2.32× CPC (θc=26o), and between that for 3.61× CPC (θc=26o) and 2.32× CPC (θc=26o). It's noticed that the difference between the instantaneous thermal efficiency of 2.32× CPC (θc=59o) and 2.32× CPC (θc=26o) is small compared with the difference of the first and second cases, the instantaneous thermal efficiency of 2.32× CPC (26o) was higher than those for other three CPCs. The experimental results show that the maximum thermal efficiency of the full 2.32×CPC (26o) is 0.708, the maximum thermal efficiency of the 3.93×CPC (15o), when it's truncated to 3.84× CPC (20o), 3.61× CPC (26o) and 2.32× CPC (59o) are 0.51, 0.52 and 0.66, respectively. As the concentration ratio decreases from (3.93× to 1×), the thermal efficiency, energy losses and optical efficiency increase from (0.47 to 63), (1.58 to 7.2 K.m2/W) and (0.494 to 0.797), respectively.
The research started from the basic objective of tracking the reality of organizational excellence in educational organizations on the basis of practical application. The research in its methodology was based on the examination of organizational excellence in the way of evaluating institutional performance. Tikrit University was selected as a case study to study the reality of application to the dimensions of organizational excellence in it, The results of the analysis for ten periods during the year and month. For the accuracy of the test and its averages, it was preferable to use the T test to determine the significance of the results compared to the basic criteria.
The research found that there is an o
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The research aims at considering the reality of cognitive bias and organizational inertia as determinants of strategic change in a sample of companies listed in Amman Stock Market. To achieve objectives of the research, a model consisting of two independent variables has been designed, namely:
(1) The cognitive bias resulting from (escalating commitment, analogy, previous assumptions, representative generalization, command and control, convergent thinking), and (2) Organizational inertia due to (Icarus discrepancy, power distribution, rooted organizational culture), and a dependent variable, strategic change in (leadership patterns, strategy, the organization per se).
From the model two main hypotheses were derived;
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Abstract
Research aims : The aim of the research is to evaluate the reality of the inspection teams' work in the health institutions belonging to Dhi-Qar health office .
Purpose: This research seeks to present a point of view based on knowing the extent of health service quality in Dhi-Qar governorate and discover the role of the inspection teams in enhancing the health service.
Design / Methodology/ Approach: The experimental method has been used and the questionnaire has also been used to collect data in order to develop a reliable and correct measurement model for the research's variables . The research's hypotheses have been tested through using some statistical treat
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The adsorption isotherms and kinetic uptakes of CO2 were measured. Adsorption isotherms were measured at two temperatures 309 K and 333 K and over a pressure range of 1 to 7 bar. Experimental data of CO2 adsorption isotherms were modeled using Langmuir, Freundlich and Temkin. Based on coefficient of correlation it was found that Langmuir isotherm model was well suited with the experimental data of CO2 adsorption isotherms. In addition, Adsorption kinetic of CO2 mixture with N2 containing 10 % by volume CO2 and 90 % by volume N2 were determined in a temperature 36 °C and under the atmospheric pressure .When the flow rate was increased from
... Show MoreThe linear segment with parabolic blend (LSPB) trajectory deviates from the specified waypoints. It is restricted to that the acceleration must be sufficiently high. In this work, it is proposed to engage modified LSPB trajectory with particle swarm optimization (PSO) so as to create through points on the trajectory. The assumption of normal LSPB method that parabolic part is centered in time around waypoints is replaced by proposed coefficients for calculating the time duration of the linear part. These coefficients are functions of velocities between through points. The velocities are obtained by PSO so as to force the LSPB trajectory passing exactly through the specified path points. Also, relations for velocity correction and exact v
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(2)
Anew Solar concentrator have been designed in this paper, this concentrators Were based on the total internal reflection in a prism, the prism angles has been calculated by depending on the solar incident ray angle in baghdad for a year. The optical design consist ofa triangular presume, Where the solar cells on one side of the prism Wh?le the prism head towered the south. The results show that there is an increasing in the solar ray concentrators and the cell area is reduced.
The aim of the research is to know the level of time management application and its impact on the performance of the job, a survey search in the general company for communication and information technology and provide recommendations that help employees to optimize the use of time and improve performance, which is an important element in controlling the various functions of the company. In order to achieve the objectives of the research, the questionnaire was based on two main variables and distributed to a random sample of (44) employees in the company out of (308) employees, thus the proportion of the sample (14%). After collecting the samples from the sample, there are (6) incomplete forms that have been retri
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Isolation and identification fungi of Emericella nidulans and Aspergillus flavus from a pinkish and yellowish artificial clay, by using potato dextrose agar (PDA). Results revealed that E. nidulans was the best for degrading anthracene (92.3%) with maximum biomass production (3.7gm/l), compared to A. flavus with the rate of degradation (89%) and biomass production of (1.2gm/l), when methylene blue was used as redox indicator after incubating in a shaker incubator 120rpm at 30Co for 8days. Results indicated that E. nidulans has a high ability of anthracene degradation with the rate of (84%), while A. flavus showed the lower level with (77%) by using HPLC.
(3)
Husain as a king of Iraq.
This paper deals with the British communication with faisel . then Winston Churchill's speech in British common house .then fodlowed by arriving faisal to Iraq after that the referend um faisel .
The his claims of British maneuver lastly coronation on faisal & his inauguration as a king of Iraq.