In a hybrid cooling solar thermal systems , a solar collector is used to convert solar energy into heat energy in order to super heat the refrigerant leaving the compressor, and this process helps in the transformation of refrigerant state from gaseous state to the liquid state in upper two-thirds of the condenser instead of the lower two-thirds such as in the traditional air-conditioning systems and this will reduce the energy needed to run the process of cooling .In this research two systems with a capacity of 2 tons each were used, a hybrid air-conditioning system with an evacuated tubes solar collector and a traditional air-conditioning system . The refrigerant of each type was R22.The comparison was in the amount of energy and current consumption of the two systems at the same operating conditions. The energy consumed and the current of the hybrid system were less than the traditional air-conditioning system by 12% and 28.6% respectively, which means that there is a saving in the energy and current consumption as a result of the use of the solar thermal collector.
Experimental research was carried out to investigate the performance of CFRP wrapping jackets used for retrofitting twelve square reinforced concrete (CR) column specimens damaged by exposure to fire flame, at different temperatures of 300, 500 and 700ºC, except for two specimens that were not burned. The specimens were then loaded axially till failure after gradual or sudden cooling. The specimens were divided into two groups containing two main reinforcement ratios, ρ= 0.0314 and ρ= 0.0542. This was followed by the retrofitting procedure that included wrapping all the specimens with two layers of CFRP fabric sheets. The test results of the retrofitted specimens showed that the fire damaged RC
... Show MoreThere are many aims of this book: The first aim is to develop a model equation that describes the spread of contamination through soils which can be used to determine the rate of environmental contamination by estimate the concentration of heavy metals (HMs) in soil. The developed model equation can be considered as a good representation for a problem of environmental contamination. The second aim of this work is to design two feed forward neural networks (FFNN) as an alternative accurate technique to determine the rate of environmental contamination which can be used to solve the model equation. The first network is to simulate the soil parameters which can be used as input data in the second suggested network, while the second network sim
... Show MoreBackground: During the pandemic, Corona virus forced many people, especially students, to spend more time than before on the computer and smartphone to study and communicate. The poor posture of the body may have worse effect on its body parts , most of which is the cervical spine (forward head posture). Objective: To assess the incidence of neck pain and the associated factors among undergraduate medical students related to position during E learning Subjects and Methods: Cross-sectional study was conducted among medical students in three Iraqi universities during 2021. The sample size was 152. Online questionnaire by Google forms sampling method were used to collect the data which was analysed using SPSS 25. Results: The perce
... Show MoreThis paper identifies and describes the textual densities of ideational metaphors through the application of GM theory (Halliday, 1994) to the textual analysis of two twentieth century English short stories: one American (The Mansion (1910-11), by Henry Jackson van Dyke Jr.), and one British (Home (1951), by William Somerset Maugham). One aim is to get at textually verifiable statistical evidence that attests to the observed dominance of GM nominalization in academic and scientific texts, rather than to fiction (e.g. Halliday and Martin (1993). Another aim is to explore any significant differentiation in GM’s us by the two short- story writers. The research has been carried out by identifying, describing, and statistically analysi
... Show MoreThis investigation aimed to explain the mechanism of MFCA by applying this method on air-cooled engine factory which was suffering from high production cost. The results of this study revealed that MFCA is a useful tool to identify losses and inefficiencies of the production process. It is found that the factory is suffering from high losses due to material energy and system losses. In conclusion, it is calculated that system losses are the highest among all the losses due to inefficient use of available production capacity.
Test results of nine reinforced concrete one way slab with and without lacing reinforcement are reported. The tests were designed to study the effect of the lacing reinforcement on the flexural response of one way slabs. The test parameters were considered is the lacing steel ratios of (0, 0.0025, 0.0045, and 0.0065), flexural steel ratios of (0.0025, 0.0045, and 0.0065) and span to the effective depth ratios of (11, 13, and 16). Two specimens had no lacing reinforcement and the remaining seven specimens had the lacing reinforcement. Four point bending test were carried out, one of the specimens was tested under the static load applied gradually up to failure and the other specimens were tested under repeated load (5 cyc
... Show MoreA restrictive relative clause (RRC hereafter), which is also known as a defining relative clause, gives essential information about a noun that comes before it: without this clause the sentence wouldn’t make much sense. A RRC can be introduced by that, which, whose, who, or whom. Givon (1993, 1995), Fox (1987), Fox and Thompson (1990) state that a RCC is used for two main functions: grounding and description. When a RRC serves the function of linking the current referent to the preceding utterance in the discourse, it does a grounding function; and when the information coded in a RRC is associated with the prior proposition frame, the RRC does a proposition-linking grounding function. Furthermore, when a RRC is not used to ground a new di
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