This paper presents an experimental study of cooling photovoltaic (PV) panels using evaporative cooling. Underground (geothermal energy) water used to extract heat from it during cooling and cleaning of PV panels. An experimental test rig was constructed and tested under hot and dusty climate conditions in Baghdad. An active cooling system was used with auxiliary an underground water tank to provide cold water as a coolant over both PV surfaces to reduce its temperature. The cellulose pad has been arranged on the back surface and sprays cooling on the front side. Two identical PV panels modules used: without cooling and evaporative water cooling. The experiments are comprised of four cases: Case (I): backside cooling, Case (II): front and back cooling (pump supply water every 35 minutes), Case (III): cooling both sides using Arduino controller. Water cooling pump operation depending on the panel temperatures (temperature sensors were installed on the front of the panel), Case (IV): Repeating case III with different water flow rates. Experimental results showed that the average reduction in module temperatures was 4, 8,12.2 and 12.6 ⁰C respectively by Case (I), (II), (III) and (IV) with respect to a non-cooling module. Using evaporative water cooling achieved a total improvement of 1.74%, 2.8%, 15.8%, and 16% in the conversion efficiency of the panel by the Case (I), (II), (III) and (IV) respectively when compared to a non-cooling module.
In light of the increasing interest in Child-rearing in nurseries and kindergartens and the most important experiences gained by the child at this stage that form the basis for the subsequent stages of her/his physical mental and social growth.
The significance of the research concentrates the need to asses the affecting variables on the child growth to create opportunities for her/him to have intact rearing.
The research also aims to classify these variables at each age level and highlight its moral role.
The problem of the research is the lack of clarity of different variables impact of the child growth in different age levels in nurseries and kindergart
... Show MoreTo assess the biochemical, mechanical and structural characteristics of retained dentin after applying three novel bromelain‑contained chemomechanical caries removal (CMCR) formulations in comparison to the conventional excavation methods (hand and rotary) and a commercial papain‑contained gel (Brix 3000). Seventy‑two extracted permanent molars with natural occlusal carious lesions (score > 4 following the International Caries Detection and Assessment System (ICDAS‑II)) were randomly allocated into six groups (n = 12) according to the excavation methods: hand excavation, rotary excavation, Brix 3000, bromelain‑contained gel (F1), bromelain‑chloramine‑T (F2), and bromelain chlorhexidine gel (F3). The superficial and deepe
... Show MoreExpected to The organizational commitment by employees increases their loyalty towards their organization and thus contribute to enhancing their performance , therefore this study aimed to discover the relationship and the impact between the organizational commitment (emotional commitment, standard commitment, continuous commitment) and the performance of employees in the company researched, additional to know the available organizational commitment levels of employees in the company researched and its impact on the performance of employees, Research was conducted at the General Company for products in the dairy to achieve the goals of research has been developed questionnaire conation (22 ) items to collect data from the study s
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The current research aims to identify mental health and its role in promoting self-confidence and positive behavior of female university students. The researcher adopted the descriptive analytical approach in this research. The researcher depended on the availability of sources and references, literature, and previous field studies to analyze and study all aspects related to mental health and its role in promoting self-confidence and positive behavior of university students and then expand its importance and identify the areas of mental health, self-confidence, positive behavior, and university. The second chapter included the concept of mental health, the importance of the study, the most important factors of health and psyc
The research aims to identify how to enhance the quality of the human resources, focusing on four dimensions (efficiency, effectiveness, flexibility, and reliability), by adopting an adventure learning method that combines theoretical and applied aspects at the same time, when developing human resources and is applied using information technology, and that Through its dimensions, which are (cooperation, interaction, communication, and understanding), as the research problem indicated a clear deficiency in the cognitive perception of the mechanism of employing adventure learning dimensions in enhancing human resources quality, so the importance of research was to present treatments and proposals to reduce this problem. To achieve
... Show MoreThe role and procedures for accountability in the spending units significant impact in enhancing the results of the budget it is found by studying and comparing the results of the implementation of the budget for the research sample for a period of two years to repeat the same deviations and irregularities of Guanyin, regulations and instructions that have occurred in implementation results and two consecutive Kaltjaoz customizations and low rates of implementation and the lack of exchange of allocations Finance despite the presence budget note that such remarks are always indicate in regulatory reports, but these observations repeated Bostmr in the results of the implementation of the budget. Which clearly reflects the absence of the ro
... Show MoreThe study focused on explaining urban expansion and sustainable development of urban land and explaining the role of population expansion in Al Hillah city, Al Hillah city in the center of Babylion Governorate located. The study relied on analyzing the population data of the city of Al Hillah for a period of time (22 years) for the period (2000-2022). This data was analyzed and its role in planning and designing residential areas and neighborhoods in the Al Hillah city was analyzed based on the standards of urban planning and sustainable growth of cities. Landsat 5TM was used in the investigation, Landsat 8OLI satellite data to retrieve the NDVI, NDBI, and NDWI. The findings showed th
Background: Ideal root canal obturation depends on many factors; one of them is good sealing of root canal without pores. The aim of this study was to determine the radiographic density of GuttaFlow® 2 with different obturation techniques using spiral computed tomography. Materials and Methods: Forty palatal roots of permanent maxillary first molar were used in this study. Following working length determination, root canal was prepared using rotary PROTAPER universal system. They were randomly divided into four groups of 10 roots each, the groups are Conventional lateral condensation with Apexit Plus sealer, Conventional lateral condensation with GuttaFlow® 2 as a sealer, Soft Core Regular with GuttaFlow® 2 as a sealer and singl
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