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Improvements in Atmosphere Sintering of Transparent PLZT Ceramics   总被引:1,自引:0,他引:1  
An improved atmosphere sintering process was developed for fabricating large transparent PLZT plates for electrooptic applications. Cold-pressed 9/85/35 PLZT slugs were sintered in O2 in Pt crucibles for ∼45 min at 1180°C and were then heat-treated in air for 60 h at 1200°C in Al2O3 crucibles containing PbZrO3 atmosphere powder. Transparent plates as large as 8.4 cm in diameter and I cm thick were thus fabricated. A mechanism is proposed which qualitatively accounts for the success of this process.  相似文献   
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1997年初我继续学习历程之前,我决定不再欣赏。而是批判甚至挖掘建筑消极的特性。我不完全成功,但这段经历让我思考一系列的问题:什么是现实?什么是虚拟?假的比真的更好吗?这些问题将我引向对建筑自疑的更高领域,当我看当代的建筑案例时,我开始流连于诚实和欺骗之间。  相似文献   
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The detailed analysis of highway locations that have been identified as hazardous within the framework of a state Highway Safety Improvement Program (HSIP) requires a great deal of time and money to perform. Given the limited resources available to state highway agencies, whose task it is to perform such analyses, it seems a worthwhile effort to automate this "location analysis." And, given the nature of location analysis problems, which are based on judgement rather than mathematical models, it was known a prior; that conventional automation techniques were not appropriate for this application. A prototype microcomputer-based expert system, which performs location analysis, was developed to assess the feasibility of applying this new technology to location analysis problems. This paper describes the prototype system, and presents a brief discussion of some of the issues that were addressed when building the system.  相似文献   
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A construction algorithm for the plant layout problem is presented. The problem is formulated as a generalized assignment problem with the objective of minimizing total movement costs. The solution algorithm is a heuristic that utilizes an analogy to the special case of locating one item within a warehouse repetitively for placing and constructing departments. The procedure is sensitive to the departmental areas and approaches the problem as one of area placement. The algorithm provides a large degree of regularity in departmental shape and overall layout outline without having to pre-specify any particular shape. The compact and simple computational nature of the algorithm makes it suitable for adaption to an interactive microcomputer environment.  相似文献   
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This paper presents an application of a new network-based simulation model to a class of production line systems and compares this with a closed form procedure. The new model is capable of analysing more realistic production lines by allowing variable work element times (normal and others), parallel stations, in-process inventory, and merging subassembly lines. Furthermore, the model is capable of handling mixed model and batched assembly situations as well as the single product assembly lines. The inclusion of cost and resource options, as integral components makes the model a powerful tool of analysis. The cost option allows evaluation of alternative configurations based on the total cost of the system; whereas, the resource feature enables one to analyse the constrained resource situations. The model can be used to optimize the design of new processing lines and to balance existing lines with a fixed production requirement.  相似文献   
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Sensory quality and storage stability of blueberry juice blends were investigated with the goal of maintaining dominant blueberry flavor, aroma and color. Apple juice, Concord and Venus grape juices and cranberry juice cocktail were blended at 75, 50 and 25% with blueberry juice. As the percent of blueberry juice decreased, the intensity of blueberry‐related sensory attributes decreased. The 25% Concord and Venus blends were the only blends that resulted in blueberry flavor similar to the reference. Apple and cranberry juice cocktail blended with blueberry juice produced several blends with good flavor and aroma, but they were not readily characterized as blueberry juice. All blends at the 25% level produced blueberry color equal to or greater than the reference. The juice samples were evaluated initially and after three months of storage at 37C. After storage, all blends had decreased red color.  相似文献   
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