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101.
H. Perez-Blanco 《International Journal of Refrigeration》1993,16(6):429-433
The search for high-efficiency, gas-fired cooling cycles has led to the development of dual-loop absorption machines with cooling coefficients of performance (COPs) in the 1.2 to 1.7 range. This increased performance may call for high generator temperatures, new working fluids or new materials of construction. In most cases, two different sets of working fluids are required. The conceptual design presented here is aimed at obtaining high efficiencies with relatively low temperatures, employing only one set of fluids. The concept consists of two loops coupled in a configuration aimed at minimizing the loss of thermodynamic availability incurred when transferring refrigerant between the loops. The working fluid pair is a solution of lithium bromide-water. The calculated COPs are of the order of 1.8. The cycle relies on an elaborate evaporator-absorber combination. The paper presents the conceptual design, the critical assumptions, and the performance calculations for the concept. 相似文献
102.
KEITH A. SCHIMMEL ALIEU WURIE SHAMSUDDIN ILIAS JAN E. PEGRAM 《Journal of food science》1996,61(3):577-580
We tested the feasibility of using polymer membranes for a self-hydrating packaging system to reconstitute freeze-dried foods using nonpurified water. Several commercial membranes were screened according to (1) hydration rate, (2) water permeability, (3) passage of microorganisms, (4) salt rejection, and (5) strength. The most promising membranes were used for developing and testing prototype packaging systems. A feasible self-contained rehydration system was a nylon-6 polyamide membrane that rehydrated the freeze-dried food within 30 min while passage of microorganisms was prevented. The temperature was 37°C, and the food contained 0.5g/5g of a low molecular weight solute (salt). Such self-contained membrane rehydration systems must be designed to accommodate expected environmental conditions such as temperature, relative humidity, and nature of the product. 相似文献
103.
J. W. PARK R.F. TESTIN P. J. VERGANO H.J. PARK C.L. WELLER 《Journal of food science》1996,61(4):766-768
The effects of various stearic-palmitic acid blend concentrations in films, storage temperatures and storage times on potato chip quality were evaluated using Response Surface Methodology. Storage temperature and time affected the quality of potato chips. The maximum storage times for acceptable potato chip quality were: 30 to 43 days, 23 to 25 days, and 11 to 12 days for storage temperatures of 15, 25 and 35°C, respectively. Results were independent of stearic-palmitic acid blend concentrations. 相似文献
104.
本文介绍了汉英机器翻译系统中从中间媒介语言生成英语的生成系统的词汇结构和功能,描述了生成系统各个层次之间的转换原理。为了说明清楚,在叙述中注意了列举从中间媒介中间媒介语言到目标语句的生成实例。 相似文献
105.
106.
论述了平板玻璃包装技术改进对提高包装质量和企业经济效益的影响,介绍了平板玻璃包装箱(架)的性能,简述了计算机辅助设计及计算机辅助管理在玻璃包装结构设计及包装质量管理中的效用。 相似文献
107.
The communicating finite state machines can exchange messages over bounded FIFO channels. In this paper, a new technique, called reverse reachability analysis, is proposed to detect deadlocks on the communication between the communicating finite state machines. The technique is based on finding reverse reachable paths starting from possible deadlock states. If a reverse reachable path can reach the initial global state, then deadlock occurs. Otherwise the communication is deadlock-free. The effectiveness of the technique has been verified by some real protocols such as a specification of X.25 call establishment/clear protocol and Bartlet's alternating bit protocol. 相似文献
108.
HVS:一个半现实全景图时空模型 总被引:7,自引:2,他引:5
利用实景图象组成具有空间感和时间感的虚拟空间,我们称之为半现实。这种具有空间“上下文”和时间“上下文”能力的半现实全景图可以应用于许多方面。文中描述了这种半现实HVS的建模思想,给出了组成时空座标系的方法,并且讨论了实现中的若干问题。 相似文献
109.
A procedure and underlying algorithm for extracting knowledge from production and inventory databases to support engineering management activities is described. The process searches for, detects and isolates behaviour patterns inherent in the data. It relates these patterns to production irregularities, suggests connections with specific causes and helps propose possible corrective or preventive actions. The approach is based on a four-phase procedure: (1) the decision-maker focuses on the subject or difficulty at issue, represented by a target concept; (2) the KEDB algorithm, based on a machine learning approach, processes the relevant database and provides knowledge characterizing and classifying the target concept; (3) the output is interpreted in Pareto fashion as a series of possible circumstances explaining the target concept behaviour; and (4) based on these causes, the decision-maker decides on possible corrective actions to improve the situation, or preventive actions to forestall unfavourable conditions. A case study based on an actual quality control database is detailed. 相似文献
110.