The performance of a vapor compression refrigeration system (VCRS)-based residential air conditioner operating in a high-ambient temperature (HAT) country was investigated using six zero-ODP (ozone depletion potential) refrigerants as replacements to R22. The non-flammable alternative refrigerants considered in the present research were R134a, R404A, R407C, R410A, R448A, and R507A. Using the basic conservation laws, the VCRS was modeled during steady-state operation and solved using engineering equation solver (EES) software. Coefficient of performance (COP), pressures and temperatures at compressor suction and discharge, Global Warming Potential (GWP), critical pressure and temperature, compressor pressure ratio, volumetric cooling capacity (VCC) specific cooling capacity (SCC), and refrigeration effect were utilized as assessment criteria for the alternative refrigerants considered. From these refrigerants, the highest values of suction pressure, discharge temperature, and condenser pressure were attained by R410A. In addition, the discharge temperatures for all refrigerants, except R134a, were all higher than their corresponding critical values, causing a quicker drop in the VCRS’s performance. As an alternative refrigerant, R407C showed the highest SCC of 141.0 kJ/kg followed directly by 139.2 and 138.0 kJ/kg for R410A and R448A, respectively. A reverse trend was found for VCC with respective values of 4722 and 3775 kJ/m3 for R410A and R448A. Lower volume flow rates and smaller-sized compressors are expected for higher VCC refrigerants. The same trend was found for the compressor’s specific work input and condenser’s specific heat transfer with values of (51.14, 46.82, and 45.38 kJ/kg) and (190.3, 187.8, and 183.4 kJ/kg) for R410A, R407C, and R448A, respectively. For applications in HAT countries, larger condenser’s specific heat transfer makes the refrigerant more applicable. Conversely, with respect to COP, refrigerant R134a with a value of 3.075 was the superior alternative followed by R448A and R407C with respective COPs of 3.042 and 3.011. Based on the overall assessment in terms of environmental obligation, COP, compressor input power, refrigerant flow rate required, and all the evaluations made in this research, refrigerant R448A was recommended as the most appropriate substitute to R22 which can effectively be used in residential air conditioners in a HAT country.
Triump is a happy end and a positive outcome of any good deed on the part of a human
being, or of any competition or contest in any field. A human being’s life abounds with gain
and loss. If one succeeds one will be happy psychologieally, physieally, etc. if one the other
hard one loses, one wil be in a state. Between loss and gain there are many a step.
However humans work hard to be a great success and a read winner.The life of the world constitutes a huge race-track where people try hard to head towards
the hereafter. Therefore, we find people who succed and gain the Garden, and people whose
habitation is the fire, The Glorious Qur’an has shown us in many a surah the way to success
when Allah mentions ‘great
This study deals with strategic maneuvering in advertisement from a pragmatic point of view found in some commercial advertisements in order to investigate and analyze the pragmatic devices that are used in the strategic maneuvering and stages. The study attempts to shed light on the most fuzzy areas in advertisements that is probably how the language of advertisements employed by advertisers to affect consumers positively. The primary goal of strategic maneuvering is to discover how the pragmatic devices have persuasive techniques that are used to gain a competitive advantage and more sales. This study is a contribution to the field of research in the language used in advertising. In this research, the effectiveness of strategic man
... Show MoreThe purpose of this paper is to develop a hybrid conceptual model for building information modelling (BIM) adoption in facilities management (FM) through the integration of the technology task fit (TTF) and the unified theory of acceptance and use of technology (UTAUT) theories. The study also aims to identify the influence factors of BIM adoption and usage in FM and identify gaps in the existing literature and to provide a holistic picture of recent research in technology acceptance and adoption in the construction industry and FM sector.
Genetic algorithms (GA) are a helpful instrument for planning and controlling the activities of a project. It is based on the technique of survival of the fittest and natural selection. GA has been used in different sectors of construction and building however that is rarely documented. This research aimed to examine the utilisation of genetic algorithms in construction project management. For this purpose, the research focused on the benefits and challenges of genetic algorithms, and the extent to which genetic algorithms is utilised in construction project management. Results showed that GA provides an ability of generating near optimal solutions which can be adopted to reduce complexity in project management and resolve difficult problem
... Show MoreBackground: Fibromyalgia syndrome (FMS) is the
most common rheumatic cause of diffuse pain and
multiple regional musculoskeletal pain and disability.
Objective: is to assess the contribution of serum
lipoprotein (A) in the pathogenesis of FMS patients.
Methods: One hundred twenty two FMS patients
were compared with 60 healthy control individuals
who were age and sex matched. All FMS features and
criteria are applied for patients and controls; patients
with secondary FMS were excluded. Serum
Lipoprotein (A): [Lp(A)], body mass index (BMI), &
s.lipid profile were determined for both groups.
Results: There was a statistical significant difference
between patients &controls in serum lipoprotein
In the current paradigms of information technology, cloud computing is the most essential kind of computer service. It satisfies the need for high-volume customers, flexible computing capabilities for a range of applications like as database archiving and business analytics, and the requirement for extra computer resources to provide a financial value for cloud providers. The purpose of this investigation is to assess the viability of doing data audits remotely inside a cloud computing setting. There includes discussion of the theory behind cloud computing and distributed storage systems, as well as the method of remote data auditing. In this research, it is mentioned to safeguard the data that is outsourced and stored in cloud serv
... Show MoreThis study deals with the concepts of Colonialism and Civilization in Aimé Cesaire’s A Tempest. The concern of this study is to discuss how postcolonial writers are continually re-writing the Western canonical works as a reaction to the European cultural hegemony. The Western representations of the black are products of specific moments and developments in history and culture. A Tempest reflects a certain historical moment in the decolonization process.
A Tempest is analysed to reveal the counter literary strategy used by Aimé Cesaire, and to disclose the reasons why re-writing and writing back are considered as vital and inescapable tasks. Shakespeare’s The Tempest, which deals with the
... Show MoreConstruction projects are characterized as projects with multi phases and activities, complex, unique, and have many different parties and stakeholders. Risks could appear at one or more of the construction project stages and may affect the achievement of project objectives. Therefore, one of the key elements in the planning phase of any project is the risk management process (RMP). This study attempts to understand the terminology of risk in general, risk management, and response to risk in particular. This study is mainly a review of thirty-eight studies that have been published between 1997 and 2020 that demonstrate the importance of the crucial phase of risk response from the risk management process and its impact on
... Show MoreCrises affect the economic growth of the country in general and the banking sector in particular. Given the importance of this sector, it is necessary to evaluate the performance of banks from time to time and monitor the liquidity of each bank and how to organize its management to overcome any crisis or emergency situation that may befall it. The research seeks to diagnose the level of impact of crisis management. In the liquidity of Iraqi private banks, using liquidity indicators, as the research community represents the banks listed in the Iraq Stock Exchange As for the research sample, it is represented by (10) pri
... Show MoreSome feline intestinal parasites such as Toxocara, Giardia, and Cryptosporidium can spread to humans through feces. Therefore, it is important to prevent exposure of family members by screening cat fecal samples twice per year for potential treatment regimes. This study was initiated to compare and identify gastrointestinal parasites of domestic and stray cats (Felis domesticus) in Baghdad City, Iraq. Parasite eggs and oocysts were identified under light microscopy by applying standard laboratory techniques (flotation and sedimentation). Overall, 59 of 121 (48.7%) fecal samples were positive for intestinal parasites. The rate of infection by Toxoplasma gondii was (3.31%), Isospora spp. (6.61%), Cryptosporidium spp. (31.4%), and Toxocara spp
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