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.
Marketing information system (KMIS) is an essential factor of developing business’ performance and getting sustainable success. The main goal of the research is to measure effect of MIS on customer orientation and product innovation. Also, another goal is to analyze the mediation role of product innovation in relationship MIS and customer orientation. This study sought to analyze the marketing information system and measure its effect on the customer orientation and product innovation. The data of the study were collected using questionnaire. The data were analyzed using statistical tools and SPSS programming. The results of the study showed that the KMIS can positively and significantly effect product innovation. Also, t
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SUMMARY. The objectives of the present study were to assess the possible predictors of COVID-19 severity and duration of hospitalization and to identify the possible correlation between patient parameters, disease severity and duration of hospitalization. The study included retrospective medical record extraction of previous coron avirus COVID-19 patients in Basra hospitals, Iraq from March 1st and May 31st, 2020. The information of the participants was investigated anonymously. All the patients’ characteristics, treatments, vital signs and laboratory tests (hematological, renal and liver function tests) were collected. The analysis was conducted using the SPSS (version 22, USA). Spearman correlation was used to measure the relations
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Photonic Crystal Fiber Interferometers (PCFIs) are widely used for sensing applications. This work presents the fabrication and the characterization of a relative humidity sensor based on a polymer-coated photonic crystal fiber that operates in a Mach- Zehnder Interferometer (MZI) transmission mode. The fabrication of the sensor involved splicing a short (1 cm) length of Photonic Crystal Fiber (PCF) between two single-mode fibers (SMF). It was then coated with a layer of agarose solution. Experimental results showed that a high humidity sensitivity of 29.37 pm/%RH was achieved within a measurement range of 27–95%RH. The sensor also showed good repeatability, small size, measurement accuracy and wide humidity range. The RH sensitivity o
... Show MoreThe research explores the confessional aspect in Audre Lorde's poem" Who Said It Was Simple ". Lorde depicts her personality under the stress of race, sex and sexuality. She discloses her own bitter experience concerning racism, sexism and sexuality in her poem to revive the retrospective truth of the Afro-Americans' life in the USA. This publicly manifestation of her personality and tribulation throughthe language ofpoetry has been regarded as the hallmark of confessional poetry.
In this work the effect of choosing tri-circular tube section had been addressed to minimize the end effector’s error, a comparison had been made between the tri-tube section and the traditional square cross section for a robot arm, the study shows that for the same weight of square section and tri-tube section the error may be reduced by about 33%.
A program had been built up by the use of MathCAD software to calculate the minimum weight of a square section robot arm that could with stand a given pay load and gives a minimum deflection. The second part of the program makes an optimization process for the dimension of the cross section and gives the dimensions of the tri-circular tube cross section that have the same weight of
... Show More- Epstein, B., and sobel , M. (1954)."Some Thearems Relevant to life Testing from an Exponential population" Annals of Mathematical Statistics, 25, 373 – 381 .
- Epstein, B., and Tsao, C.K.(1953) "Some Tests Based on Order Observation From Two Exponential Populations" Annals of Mathematical Statistics , 24 , 458 – 466 .
- Hogg, R.V. and Tonis, E,A. (1963), "An Iterated procedure for Testing the Equality of several Exponential Distributions" Journal of the American Statistical Association, 58 , 435 – 443.
- Kumar, S. , and patel , H. I. (1971) "ATest for the Comparision of two Exponential Disributions" Technometrics , 13 , 183 – 189 .<
Research problem: the problem of the current research can determine the dimensions of answering the following question - What is the impact of the use strategy summaries tribal collection and retention in the second grade students in the middle of history?
The importance of research: In order to achieve the desired education and access to educational goals required, and to address all the challenges facing the educational process, so you may need to use methods and different educational methods in the teaching of social history, particularly, of those methods and modalities to adopt strategies tribal in teaching, has chosen researcher summaries tribal style, which is one of the strategies of goo
This research aims to assess the adoption of TQM in the Middle East Bank for Investment, and diagnosis means and techniques of technological innovation that applied in, as well as to determine the nature of the relationship between total quality management practices (operations management, employment relations, customer relations) and technological innovation (the incremental innovation of the service, incremental innovation process, a radical innovation of the service, a radical innovation of the operation), through use the checklists, derived from a study (Kim et al, 2012) the many styles of mathematical and statistical tools was adopted like the percentage, mean, duplicates, as well as the adoption of the Z test th
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لقد أدت التطورات العلمية والتقنية وتطبيقاتها العملية في مختلف ميادين الحياة بشكل عام وميدان التربية والتعليم بشكل خاص إلى ظهور تغيرات في البناء التعليمي وطرائق التدريس بصيغتها الحديثة التي تنسجم في مجملها وروح العصر مما دعى المؤسسات التربوية والتعليمية وبإيعاز إلى الباحثين والمهتمين بهذا الميدان الى ضرورة متابعة الاتجاهات الحديثة ونواحي التجديد لمحتوى العملية التعليمية فيما يتعلق بالمجالات المعر
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