A methodology for optimal product positioning with engineering constraints consideration

Due to the complex mapping relationship between product attributes and engineering characteristics, as well as the correlations between engineering characteristics and the engineering constraints on a product, a new product following a probabilistic rule of multidimensional scaling may not be in an optimal position in product engineering space. In this paper, a new methodology for optimal product positioning by considering engineering constraints is proposed. In the proposed methodology, perceptual mapping and house of quality are introduced to link the consumer perceptual space, and product engineering space. The degree of overall customer satisfaction is considered in the rule of consumer choice probability. Based on this, an optimal product positioning model can be established. Genetic algorithms are introduced to solve the problem of the optimization model due to its non-linear characteristics. By applying genetic algorithms, the optimal value settings of a new product's engineering characteristics can be obtained. An example of optimal positioning and determination of value settings of engineering characteristics of packing machines is used to illustrate the proposed methodology.     

极小掠射角下分层海底的声反射损失研究

选取浅海大陆架的一种典型海底情况,建立了水-低声速沉积物-高声速海底半空间的分层海底模型.在极小掠射角的情况下,通过计算总的反射系数,并对反射系数的表达式进行变换,分析了分层海底的声反射损失.结果表明:反射系数的极点处出现了反射损失的突变,即在沉积层厚度与波长的比值为一系列特定值时,出现了高反射损失;同时反射损失在掠射...     

高职院校《计算机平面设计》课程教学的探讨

从计算机平面设计课程特点和职业教育需求角度,对计算机平面设计课程教学进行探讨。提出依据不同因素对课程教学进行定位,确定教学内容、教学方法和教学模式。在课程教学方案实施过程中,树立正确的课程教学观念,整合教学内容,综合运用不同的教学方式。在教学效果评价方面建立校内评价和校外评价相结合兼顾认证竞赛成绩的五环式综合教学效果评价机制。     

简析小教大专中文专业写作教学定位

探讨小教大专写作教学，根据小教大专的特点定位：正确选择教材，合理选用教法，明确培养目标。深化教学改革，圆满完成小教大专的写作教学任务。     

GPS与GIS集成定位在铁路列车上的应用

针对GPS(全球卫星定位系统)单独定位系统存在的缺陷,对GPS与地理空间信息系统GIS相结合的铁路列车定位的工作原理、铁路GIS地图数据库的建立、GPS与GIS间的接口、GPS坐标与数字地图强制匹配的算法及GIS距离推算等问题做了初步阐述。     

Three‐dimensional flow dynamics around deflectors

Many river rehabilitation projects to enhance the aquatic habitat focus on the creation of pool and riffle habitat by the implementation of flow deflectors, with various degrees of successes and failures. A more comprehensive understanding of the complex three‐dimensional flow dynamics that induces scour around instream structures is required for a more effective design. The objective of this study is to examine the three‐dimensional mean and turbulent flow characteristics around paired flow deflectors for various types of deflector design in a laboratory flume. Three deflector angles (45°, 90° and 135°) and two deflector heights (with flow under and over the deflector height) were tested over a smooth (plexiglas) bed and a sand bed. Three‐dimensional velocity measurements were taken with an acoustic Doppler velocimeter at several planform positions at two heights above the bed. Results show that the 90° deflectors create the most important disturbance in the mean flow field, in turbulence intensity and bed shear stress. There is, however, a marked difference in the spatial distribution of the mean and turbulent parameters over a mobile bed and over a smooth, fixed bed. This stresses the importance of understanding the feedback between bed topography and flow dynamics and limits the applicability of conclusions drawn from plane bed experiments to natural rivers. Copyright © 2005 John Wiley & Sons, Ltd.     

北斗通信技术在光照水电站水情测报系统中的应用

介绍了北斗卫星导航定位系统的简短通信技术。北斗卫星的简短通信功能允许用户与用户、用户与地面控制中心之间进行双向数据传输。针对水情自动测报系统中远程数据传输通道的特点，提供了应用北斗系统进行实时数据远程传输的设计方案，并在光照水电站水情测报系统中得到应用。     

构皮滩水电站碾压混凝土围堰可利用性爆破拆除施工

构皮滩水电站下游碾压混凝土围堰爆破拆除是大体积碾压混凝土可利用性爆破拆除，其下部结构作为永久建筑物，需要拆除上部的碾压混凝土。2006年12月10日爆破成功，从安全监测资料与爆破前后的声波检测显示，本次爆破满足设计要求，是一次成功的可利用性爆破拆除。     

用时延编码实现远程水声通信

本文研究了一种基于时延编码的远程水声通信技术，该技术利用线性调频（LFM）信号矩形脉冲的时延值进行时延编码，在接收端采用时延估计技术进行时延解码。初步的海试结果表明，该技术可以实现80km距离、4.16bit/s数据率的信息可靠传输。     

美国住房反抵押贷款及引入我国可行性评析

住房反抵押贷款是重要金融创新,在发达国家变得越来越流行。它是居民以自有产权作为抵押,定期向金融机构取得的主要用于养老费用的贷款。反抵押贷款提高了住房的流动性,对提高老人生活质量有积极作用。从美国反抵押贷款发展的特点、存在问题来看,反抵押贷款业务在我国有一定的需求潜力。同时新业务在我国的市场必须正确定位,才能将潜在的需求转化为现实的市场。