The standard formulation of Wave Intensity Analysis (WIA) assumes that the flow velocity (U) in the conduit is <;<; the velocity of propagation of waves (c) in the system, and Mach number, M=U/c, is negligible. However, in the large conduit arteries, U is relatively high due to ventricular contraction and c is relatively low due to the large compliance; thus M is > 0, and may not be ignored. Therefore, the aim of this study is to identify experimentally the relationship between M and the reflection coefficient in vitro. Combinations of flexible tubes, of 2 m in length with isotropic and uniform circular cross sectional area along their longitudinal axes, were used to present mother and daughter tubes to produce a range of reflection coefficients. An approximately semi-sinusoidal pulse was generated at the inlet of the mother tube using a syringe pump, first in the condition of initial velocity, U 0 =0, and when U 0 >0 with steady flow to superimpose the pulse. Pressure (P) and Velocity (U) were measured in the mother tube, wave speed was determined using the foot to foot and PU-loops methods. The theoretical reflection coefficient, R t at M=0, has been compared to the experimental reflection coefficient, R at M>0, which was determined as dP-/dP+ as calculated using WIA. The function R(M) changes significantly with the geometrical and mechanical features of the connected tubes. In our experiments, R increased significantly with small values of M. In the range of M=0-0.02, R increased by 4-36%. Therefore, we conclude that M significantly affects the magnitude of reflections.
The construction project is a very complicated work by its nature and requires specialized knowledge to lead it to success. The construction project is complicated socially, technically and economically in its planning, management and implementation aspects due to the fact that it has many variables and multiple stakeholders in addition to being affected by the surrounding environment. Successful projects depend on three fundamental points which are cost-time, performance and specifications. The project stakeholder's objective to achieve best specifications and the cost-time frame stipulated in the contract.
The question is, was the optimum implementation accomplished? The provision for the success of the project
... Show MoreThe Quality function deployment (QFD) tool is an important tool of total quality management because its a link between two important parts customer and production process of the product, using advanced House of quality, which contributed to provide more details about improving the product before it had a vision for the future of the product be improved. Also the identification of the two competitors (Alwazeer , Altouri) bases on the survey of retailers which they identified five competitors products (Alwazeer , Altouri , Ferry , Jif , Dina)for the product (Zahi). Then House of quality to product (Zahi) has been developed By using a Kano Model to classify of customer's requirements for the
... Show MoreWorldwide, hundreds of millions of people have been infected with COVID-19 since December 2019; however, about 20% or less developed severe symptoms. The main aim of the current study was to assess the relationship between the severity of Covid-19 and different clinical and laboratory parameters. A total number of 466 Arabs have willingly joined this prospective cohort. Out of the total number, 297 subjects (63.7%) had negative COVID-19 tests, and thus, they were recruited as controls, while 169 subjects (36.3%) who tested positive for COVID-19 were enrolled as cases. Out of the total number of COVID-19 patients, 127 (75.15%) presented with mild symptoms, and 42 (24.85%) had severe symptoms. The age range for the partic
... Show MoreThe importance of the construction sector and its Great role in the provision of services and infrastructure, reduce poverty, improve living conditions and improve the economic situation in the country, impose attention to the way in which the projects implemented for its improvement and to get successful projects. The objective of this research was to determine the criteria for success as well as critical success and failure factors that have a significant impact on project success. A selected 75 engineer (department managers, project managers and engineers) are asked to fill the questionnaire form, Sixty-seven valid questionnaire forms were analyzed statistically to get search results, which were as follows : Twe
... Show MoreThis research was aimed to evaluate activity of Rosemary volatile oil and Nisin A in vivo and on B. cereus isolated from some canned meat products in vitro. The results showed that the activity of Rosemary volatile oil (2000 µg/ml) and Nisin A (350 µg\ml) attained to 27 and 19 mm inhibitory zone diameter respectively in well diffusion method. The viable plate count from samples of canned meat treated with effective concentration of Rosemary volatile oil and Nisin A were examined. The samples with Rosemary volatile oil was not showed any CFU/g after 9 days of preservation while sample with Nisin A and control observed 49 and 45 CFU/g respectively. In vivo experiment on mice, two weeks after oral dose of Rosemary volatile oil (2000
... Show MoreConflict, peace, and sports have a long history as practical realities, and their correlation has become an important subject of study in the last decades of the twentieth century. Sport has infiltrated peace and conflict studies as a tool for resolving conflict and building peace, but opinions have differed between those who say it is a positive tool and others who see it as negative. The Gulf Cup is one of the champions that have never been studied, and in-depth research about it has not been done. This tournament has affected the relations between the states involved. The politics cast its shadow on the Gulf Cup. The paper aims to shed light on how political events in the region have consistently affected the Gulf Cup and how politics in
... Show MoreThe purpose of this paper is to introduce and study the concepts of fuzzy generalized open sets, fuzzy generalized closed sets, generalized continuous fuzzy proper functions and prove results about these concepts.
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 5
... Show MoreAn experimental investigation has been carried out for zinc-nickel (Zn-Ni) electro-deposition using the constant applied current technique. Weight difference approach method was used to determine the cathode current efficiency and deposit thickness. Also, the influence effect of current density on the deposition process, solderability, and porosity of the plating layer in microelectronic applications were examined. The bath temperature effect on nickel composition and the form of the contract was studied using Scanning Electron Microscope (SEM). Moreover, elemental nature of the deposition was analyzed by Energy Dispersive X-Ray (EDX).
It has been found that the best bath temperature
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To evaluate the effectiveness of Phenolic Compound of Salvia Frigida on induced atopic dermatitis (AD) of mice. Forty mice were included in the study, divided in to four groups (10 mice/group): apparently healthy, induced AD without treatment, induced AD treated with tacrolimus 0.1% ointment, and induced AD treated with Phenolic Compound of Salvia Frigida cream 5%. Examination of histopathology was done and skin homogenates levels also measured. Levels of WBC, Eosinophil, skin tissue homogenate of IL-13 and IL-4, serum IgE, and histopathological scores were significantly increased among induced non treated AD group in comparison with control group. Comparisons of non-treated induced AD
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