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11.
A study was made of pressure drop during single fluid phase flow to determine the pressure drop characteristic of the porous media (glass ballotini particulate beds) for coalescence. It is also served to check the reproducibility of the packing technique, and to detect any foreign particulate matter or re-arrangement of the individual particles in the coalesce bed. Furthermore these data provided a basis for comparison with that during two-phase flow with coalescence. For spherical particle the modified Carman-Kozeny equation was applied; the commonly accepted value for Kozeny constant is 5.0. However, K, depends on, among other factors, the structure of the bed, voidage fraction, particle shape, tortuosity, superficial velocity, bed depth, particle size, and wall effect.  相似文献   
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The cost estimate is considered one of the most important and critical phases of a construction project. Preparing reliable and accurate estimates to help decision makers is the most challenging assignment that cost engineers and estimators face. For decades, practitioners in the construction industry focused only on estimating the initial cost of a facility, neglecting costs associated with operating and maintaining it. Today, more interest lies in investigating the economics of facility management, which include the cost of owning and operating a building over its useful life. This paper presents a methodology that can be used for an integrated conceptual cost estimating and life-cycle cost analysis for construction projects during their initial phase. The methodology describes the development and implementation of a system that automates the preparation of parametric cost estimates and forecasts future running costs of building projects. The system integrates relational databases, a parametric cost estimate module, an AutoCAD module, a global module, a cost estimate forecasting and decision support system module, and a life cycle costing and sensitivity analysis module. The system will automatically generate a new parametric estimate upon any modification in building design. Once the capital costs are identified, the system forecasts the cost of running and maintaining the new building throughout its expected service life. After assigning the range of deviation, a sensitivity analysis is conducted, which identifies the most sensitive parameters for further consideration and analysis. Designing the system in a user-friendly environment allows owners and decision makers to envision the feasibility of new building projects within their anticipated life cycles. Moreover, it assists architects and cost engineers in generating parametric cost estimates in a dynamic environment. A numerical case example is presented to illustrate the usefulness and capabilities of the developed system.  相似文献   
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In this study, gum arabic powder was produced according to four methods by inserting a restructuring stage by DIC treatment (instant controlled pressure drop) in the classic process of grinding and spray drying. Properties of the final product were compared, and the results show that DIC treatment enables to control and improve the properties of the powder. The DIC treatment can cause a controlled increase in the tapped bulk density, filling rate, compressibility, porosity; and a reduction in interstitial air volume and the loose bulk density. It also facilitated the subsequent grinding and intensified the drying kinetics. The impacts of pressure and DIC treatment time were examined. Pressure was the strongest factor influencing the properties of the gum arabic powder. Selecting an optimal pressure and treatment time plays a decisive role in controlling the properties of powders.  相似文献   
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Education quality has undoubtedly become an important local and international benchmark for education, and an institute’s ranking is assessed based on the quality of education, research projects, theses, and dissertations, which has always been controversial. Hence, this research paper is influenced by the institutes ranking all over the world. The data of institutes are obtained through Google Scholar (GS), as input to investigate the United Kingdom’s Research Excellence Framework (UK-REF) process. For this purpose, the current research used a Bespoke Program to evaluate the institutes’ ranking based on their source. The bespoke program requires changes to improve the results by addressing these methodological issues: Firstly, Redundant profiles, which increased their citation and rank to produce false results. Secondly, the exclusion of theses and dissertation documents to retrieve the actual publications to count for citations. Thirdly, the elimination of falsely owned articles from scholars’ profiles. To accomplish this task, the experimental design referred to collecting data from 120 UK-REF institutes and GS for the present year to enhance its correlation analysis in this new evaluation. The data extracted from GS is processed into structured data, and afterward, it is utilized to generate statistical computations of citations’ analysis that contribute to the ranking based on their citations. The research promoted the predictive approach of correlational research. Furthermore, experimental evaluation reported encouraging results in comparison to the previous modification made by the proposed taxonomy. This paper discussed the limitations of the current evaluation and suggested the potential paths to improve the research impact algorithm.  相似文献   
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Most decision situations in business, manufacturing and service industries represent problems with multiple alternatives where more than one objective needs to be considered in evaluating mutually exclusive strategies. A variety of approaches have been proposed and employed for evaluating such multi-attribute problems. These approaches generally utilize single point or most likely estimates in the evaluation process. This paper addresses the problem of developing a probabilistic additive weighting methodology which facilitates the inclusion of variability in the evaluation procedure.  相似文献   
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RAS mutations occur frequently in acute myeloid leukaemia and myelodysplasia, suggesting a functional role for this oncogene in leukaemogenesis. We show here, for the first time, that both N-RAS and H-RAS can impair erythroid differentiation of erythroleukaemia cells induced with hexamethylene bisacetamide. Transformation by RAS allowed extended proliferation in the presence of inducer and also inhibited maturation as measured by impaired haemoglobinization and reduction in cell size. These data provide an interesting counterpoint to the effect of mutant RAS on monocytic cells, where it has a potentiating effect on differentiation and may indicate a causal link between the activation of RAS and erythroid lineage dysplasia in preleukaemia.  相似文献   
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A function generator is described that basically generates a trapezoidal waveform whose leading and trailing ramps and positive and negative plateaus can be varied in duration, independently, between 0.5 ms and 50 s. By appropriate interconnections between the constituent units of the generator, a total of 12 different waveforms are generated, including triangular, sinusoidal, square, rectangular, and sawtooth waveforms. The output may be either free running or externally triggered to produce an adjustable integral number of cycles.  相似文献   
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