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International aid agencies undertake supplementary feeding programmes following disasters in order to alleviate or prevent protein energy malnutrition. The associated problems include lack of facilities for preparation and distribution of food on site and food hygiene dangers. In response to these factors a biscuit of high calorific value and acceptable organoleptic qualities has been developed. It is currently being used by Oxfam as part of their disaster relief programme in Ethiopia.  相似文献   
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为在现场可编程门阵列(FPGA)中实现快速高精度除法,在传统的倒数除法的基础上,提出一种改进算法.对倒数求解采用泰勒级数展开结合优化搜索逼近,求出各个分区间内的拟合一次两项式,再通过一次牛顿迭代提高精度.时序仿真结果表明,以该算法构建的除法器易于在FPGA上实现,时延仅为6个时钟周期,能达到2(-34)的有效精度和86...  相似文献   
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Tip vortex cavitation noise of marine propeller became primary concerns to reduce hazardous environmental impacts from commercial ship or to keep the underwater surveillance of naval ships. The investigations of the tip vortex and its induced noise are normally conducted through the model test in a water cavitation tunnel. However the Reynolds number of model-test is much smaller than that of the full-scale, which subsequently results in the difference of tip vortex cavitation inception. Hence, the scaling law between model-and full-scales needs to be identified prior to the prediction and assessment of propeller noise in full scale. From previous researches, it is generally known that the incipient caivtation number of tip vortex can be represented as a power of the Reynolds number. However, the power exponent for scaling, which is the main focus of this research, has not been clearly studied yet. This paper deals with the estimation of scaling exponent based on tip vortex cavitation inception test in both full-and model-scale ships. Acoustical measurements as well as several kind of signal processing technique for an inception criterion suggest the scaling exponent as 0.30. The scaling value proposed in this study shows slight difference to the one of most recent research. Besides, extrapolation of model-ship noise measurement using the proposed one predicts the full-scale noise measurement with an acceptable discrepancy.  相似文献   
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Modern manufacturing economics is an interdisciplinary research subject which deals with the cycles of performance measurement, cost estimation, and decision analysis that are enmeshed with quantification of ill-structured benefits of advanced manufacturing technologies (AMT). This paper proposes a framework of modern manufacturing economics by examining recent research trends of AMT economics. It underscores integrated, quantitative, global, and strategic studies of AMT economics.  相似文献   
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The information needs of a complex society are not met by an information-flow technology invented and developed in traditional societies. This article provides a theoretical framework derived from modern systems theory by which to understand the technology of public opinion policy formation in guidance operations of a complex society. Qualitative models of information flow systems are presented together with a discussion of the kind of society each information flow technology produces. Three are considered: tradition-based information-flow societies, managed information-flow societies (Utopian and elitist), and cybernetic issue-based information-flow societies.  相似文献   
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The effective parameters on the diameter of carbon nanotubes (CNTs) by plasma enhanced chemical vapor deposition (PECVD) were presented.Among lots of influential parameters,the effects of the catalytic film thickness and the pretreatment plasma power on the growth of CNTs were investigated.The results show that the size of catalytic islands increases by increasing the thickness of catalytic layer,but the density of CNTs decreases.The pretreatment duration time of 30 s is the optimal condition for growing CNTs with about 50 nm in diameter.By increasing the pretreatment plasma power,the diameter of CNTs decreases gradually.However,the diameter of CNTs does not change drastically from 80 to 120 W.The uniformly grown CNTs with the diameter of 50 nm are obtained at the pretreatment plasma power of 100 W.  相似文献   
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