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排序方式: 共有1043条查询结果,搜索用时 15 毫秒
1.
Ali Farman Ali Zulfiqar Li Bing-Zhao Qamar Sadia Nazeer Amna Riaz Saba Khan Muhammad Asif Fayyaz Rabia Nawaz Abbasi Javeria 《Water Resources Management》2022,36(9):2989-3005
Water Resources Management - Drought is recurrently occurring in many parts of the globe. In contrast to other natural hazards, drought has complex climatic characteristics. Several environmental... 相似文献
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Izhar AHMAD Kashif Ali KHAN Tahir AHMAD Muhammad ALAM Muhammad Tariq BASHIR 《Frontiers of Structural and Civil Engineering》2022,16(5):589
In recent building practice, rapid construction is one of the principal requisites. Furthermore, in designing concrete structures, compressive strength is the most significant of all parameters. While 3-d and 7-d compressive strength reflects the strengths at early phases, the ultimate strength is paramount. An effort has been made in this study to develop mathematical models for predicting compressive strength of concrete incorporating ethylene vinyl acetate (EVA) at the later phases. Kolmogorov-Smirnov (KS) goodness-of-fit test was used to examine distribution of the data. The compressive strength of EVA-modified concrete was studied by incorporating various concentrations of EVA as an admixture and by testing at ages of 28, 56, 90, 120, 210, and 365 d. An accelerated compressive strength at 3.5 hours was considered as a reference strength on the basis of which all the specified strengths were predicted by means of linear regression fit. Based on the results of KS goodness-of-fit test, it was concluded that KS test statistics value (D) in each case was lower than the critical value 0.521 for a significance level of 0.05, which demonstrated that the data was normally distributed. Based on the results of compressive strength test, it was concluded that the strength of EVA-modified specimens increased at all ages and the optimum dosage of EVA was achieved at 16% concentration. Furthermore, it was concluded that predicted compressive strength values lies within a 6% difference from the actual strength values for all the mixes, which indicates the practicability of the regression equations. This research work may help in understanding the role of EVA as a viable material in polymer-based cement composites. 相似文献
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Farzad Saberi Fatemeh Kouhsari Samaneh Abbasi Cristina M. Rosell Mehdi Amini 《International Journal of Food Science & Technology》2021,56(12):6559-6571
The aim of the study was to evaluate the physical and microstructural characteristics of crackers baked in four different industrial baking ovens (indirect radiation-cyclotherm, indirect convection, hybrid and industrial tunnel-ITO). Indirect convection and cyclotherm ovens provide the highest (5685.43 ± 51 W m−2) and the lowest (4860 ± 38.87 W m−2) amount of heat flux, respectively. Despite the amount of heat flux, indirect convection led to crackers with the highest moisture (7.86% vs. 4.82% in clyclotherm) and specific volume, but the lowest hardness. Cyclotherm resulted in crackers with lower specific volume, surface area, porosity, smooth and regular surface. Conversely, the hybrid and ITO ovens showed closer heat flux, leading to crackers with similar moisture content, texture parameters, specific volume, browning and inner porosity. Overall results show the potential of baking using different ovens for modifying the quality parameters of the crackers. 相似文献
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Wireless Personal Communications - Delay tolerant networks are among mobile ad hoc networks. There is not a complete and connected route between the source and destination in these networks due to... 相似文献
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A. Basheer S. M. Tauseef Tasneem Abbasi S. A. Abbasi 《Journal of Failure Analysis and Prevention》2018,18(1):83-91
A new method, RIsk and DIstance Minimization in Process Units Siting (RIDIMPUS), is presented with which hazardous units can be sited in a chemical process facility in a manner that the risk of accidents involving the hazardous units as also the cost of spacing the units is minimized. To achieve this, safety and cost factors were modeled using various governing parameters and then expressions were designed to integrate the safety and the economic concerns to form model equations, inequalities and disjunctions. The resulting nonlinear programming model is solvable by using algorithms and solvers on any common desktop computer, thereby providing an optimal and prompt solution. 相似文献
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Morteza Abbasi Reza Derakhshandeh-Haghighi 《The Physics of Metals and Metallography》2018,119(5):497-503
The weldability of aluminum bronze alloys lends it to fabrication of items such as pipes and pressure vessels. Thus, obtaining high strength along with good ductility is necessary. Gas tungsten arc welding of Cu–7Al–3Fe aluminum bronze alloy was performed by variation of some parameters such as shielding gas flow rate, preheat and post weld heat treatment. Optical and scanning electron microscopy along with EDX analysis was applied for different samples. Microhardness measurements and tensile tests were performed to see the effect of these parameters on ultimate tensile strength and ductility of samples. 相似文献
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