The present work deals with an experimental investigation of charging and discharging processes in thermal storage system using a phase change material PCM. Paraffin wax was used as the PCM which is formed in spherical capsules and packed in a cylindrical packed column which acted as an energy storage system. Air was used as the heat transfer fluid HTF in thermal storage unit. The effect of flow rate and inlet temperature of HTF on the time of charging and discharging process were studied. The results showed that the faster storage of thermal energy can be made by high flow rate of heat transfer fluid HTF and high inlet temperature of heat transfer fluid. It was found that at 65°C HTF inlet temperature, the melting and solidification processes accelerated by 27.9% and 57.14% respectively, when the flow rate was increased from 9 to 24 L/s. Also, when the HTF inlet temperature changed from 65°C to 80°C, the time needed to complete melting process decreased by 38.8%.
Starting with a problem of the weakness of accounting disclosure in some companies administration when preparing and presenting the financial reports which are submitted to the Tax authority. This problem impacts on Tax authority performance (The effect on the quality of the performance of the tax authority), because of the lack of conviction for the information contained in those reports, and the failure to achieve accurate results in tax authority performance that leads to a negative impact on determining taxable income and affect tax revenue, as well as negative impact on determining taxable income and affect tax revenue, as well as negati
... Show MoreThe research aims to identify the elements of performance supervisory good and effective and availability in the Governmental council through examination and analysis of the reality and practice of censorship in this Council through study and evaluate the characteristics of the regulatory effective upon which the Governmental council in the performance of his work and knowledge of their adequacy by comparing the established criteria , and determine the effect of characteristics supervisory the performance standards for the Governmental council, Based search to two assumptions key to check the level of the relationship and the influence of the dimensions of the con
... Show MoreThis study seeks to address the impact of marketing knowledge dimensions (product, price, promotion, distribution) on the organizational performance in relation to a number of variables which are (efficiency, effectiveness, market share, customer satisfaction), and seeks to reveal the role of marketing knowledge in organizational performance.
In order to achieve the objective of the study the researcher has adopted a hypothetical model that reflects the logical relationships between the variables of the study. In order to reveal the nature of these relationships, several hypotheses have been presented as tentative solutions and this study seeks to verify the validity of these hypotheses.
... Show MoreThe aim of the study is to prepare a measure of the role of academic coaches in handball skill performance from the point of view of the researchers. The researchers used the descriptive approach in the research procedures as it is an appropriate approach in achieving the research objectives. The next question is: To what extent will the players benefit from the academic coach in developing their skill performance? This is the measure of the role of academic coaches. From 16 items, the research community included players (Al-Karkh Club - Al-Hashd Sports Club) and the number of players was (Al-Karkh 14 - Al-Hashd 14). The research sample was intentional and represented (the research community 100% The researchers concluded that measuring the
... Show MoreBackground: This study was conducted to evaluate the surface roughness and dimensional accuracy of commercially obtainable alginate impression material in terms of imbibition after immersion in two different media. Materials and method: Two disinfecting agents, ethanol 70% and povidone-iodine 4%, were used to access the dimensional accuracy and surface roughness of alginate impression material. Weights of specimen discs of alginate impressions were measured before and immediately after immersion to gain a measure of imbibition. For surface roughness, disinfected specimens rectangle was examined before and after disinfection. Results: Minimal changes in weight were observed after disinfection, but a statistically non-significant differenc
... Show MoreThe Pulse Coupled Oscillator (PCO) has attracted substantial attention and widely used in wireless sensor networks (WSNs), where it utilizes firefly synchronization to attract mating partners, similar to artificial occurrences that mimic natural phenomena. However, the PCO model might not be applicable for simultaneous transmission and data reception because of energy constraints. Thus, an energy-efficient pulse coupled oscillator (EEPCO) has been proposed, which employs the self-organizing method by combining biologically and non-biologically inspired network systems and has proven to reduce the transmission delay and energy consumption of sensor nodes. However, the EEPCO method has only been experimented in attack-free networks without
... Show MoreThe dynamic thermomechanical properties, sealing ability, and voids formation of an experimental obturation hydroxyapatite-reinforced polyethylene (HA/PE) composite/carrier system were investigated and compared with those of a commercial system [GuttaCore (GC)]. The HA/PE system was specifically designed using a melt-extrusion process. The viscoelastic properties of HA/PE were determined using a dynamic thermomechanical analyser. Human single-rooted teeth were endodontically instrumented and obturated using HA/PE or GC systems, and then sealing ability was assessed using a fluid filtration system. In addition, micro-computed tomography (μCT) was used to quantify apparent voids within the root-canal space. The data were statistically analys
... Show MoreIntroduction: An aneurysmal bone cyst are enigmatic lesionof unknown cause and presentation and are difficult todistinguish from other lesions, it is a benign, but expansibletumor like lesion that generally occurs in the long bones. Ananeurysmal bone cyst arising from the flat bone like clavicleis rare .Case presentation: We report a 12-year-old girl child with ananeurysmal bone cyst of the lateral third of left clavicletreated with enblock resection. The pathologic findingsconfirmed the diagnosis of aneurysmal bone cyst. Thepatient has been followed up for one year with no evidenceof recurrence .Conclusion: En bloc resection can be curative and provide good results for this rare type of clavicle tumour.
The book The Laws of Duwan of Mamati's Son (T, 606 E) His approach to his narratives is a topic of historical and civilized importance. The Fatimid Age of the People of Jehovah has expanded its influence and authority, including ministers, writers, doughnuts and foreshores. One of the Christian families that shined in the late Fatmi era was "Mamati", who lived in "Assiut" from Upper Egypt, then moved to Cairo, and enrolled in the service of the Fatimids, where their sons held important positions in State offices.Ibn Mamati became in charge of the Army Office and then added to it the Finance Office, which became the most important downs in Egypt. Through his work in the Duwan Law Books, this book was a living record of the Dawawans in the Ay
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