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981.
W. M. Waite 《Software》1975,5(3):295-308
Would-be implementors of portable software often encounter frustrating difficulties when attempting to enter the distributed text into their computers. This paper summarizes various problems which may arise, and indicates how the distributor can head them off. The conventions used by several successful distributors are given to illustrate possible solutions. 相似文献
982.
论述威尔兹法初级氧化锌在煅烧脱杂过程中的一系列物理化学变化,介绍回转窑煅烧脱杂试验所取得的技术经济指标及工业应用前景。 相似文献
983.
Reinhard Klette 《Pattern recognition letters》1983,2(1):19-22
The outer or inner approximation of the convex hull of a grid point set may be used to speed up the feature extraction process in a shape analysis system. Some properties of these approximations are given. 相似文献
984.
并元加集与二元并元码 总被引:6,自引:1,他引:5
本文首先进一步研究了并元加集存在的必要条件,从而提出了二元并元码所具有的长度。然后给出了一系列二元并元码的构造方法。证明了存在长度为22t+2的二元并元码,相应地证明了存在参数为(22t+2,22t+1±2t,22t±2t)的并元加集。 相似文献
985.
A. Z. Tirkel C. F. Osborne N. Mee G. A. Rankin A. McAndrew 《International Journal of Communication Systems》1994,7(1):29-32
Current trends in personal and data communication networks favour code division multiple access (CDMA) as a solution to spectral congestion. This is because of enhanced capacity, security, network flexibility, simplified protocol, and relative immunity to propagation induced errors such as multipath and interference, as compared with traditional frequency division multiple access (FDMA). Various CDMA schemes have been proposed and described in relation to VSAT systems, local area microcells,2 and cellular telephones. Additionally, numerous product applications have emerged in the areas of modems, voice links and wireless local exchanges. These systems require inter- and intra-cell control. By contrast, the scheme presented in this paper places no reliance on intercell protocol. It enables new cells to be added to the network without any impact on the hardware. Network reconfiguration requires software changes only. Therefore, the scheme is appropriate to systems which demand flexibility with minimum overheads. 相似文献
986.
The definition of fuzzy convexity is reviewed and some results on projections of convex and fuzzy convex sets are established. Digital fuzzy convexity is defined and relationships among alternative definitions are investigated. 相似文献
987.
Immediate recall for spatial information was studied as a function of stimulus load under 2 display formats, 2 response formats, and 2 response set conditions. 4 groups of 10 Ss each served under 15 replications of all response-format, stimulus-load conditions; groups were distinguished on the basis of display format and set. Each S viewed either a spatial or tabular display of 14-26 geometrical stimuli for 16 sec.; he was then required to report, on either a tabular or spatial response form, the location of relevant stimuli. Correct responses and misplacement errors increased more rapidly for the spatial format as more stimuli were presented. Recoding from 1 display to the other response format did not yield serious decrements. Contrary to expectation, response set enhanced all conditions to a nearly equivalent degree. Results are interpreted in terms of the "chunking" hypothesis. (16 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
988.
文献〔1〕给出了L-fuzzy集上(G)fuzzy积分的定义,本文指出了L-fuzzy集上(G)fuzzy积分方程∫xf(x)dμ=β有解的充要条件,特别是对于一个固定的非负μ可测函数h(x),得到了积分方程∫x(h(x)∧f(x))dμ=β有解的充要条件,从而改进并推广了文献〔2〕和〔3〕的主要结果。 相似文献
989.
A new parameter is introduced into the contact model of rough surfaces which characterizes the contact spot density. Based on the present mathematical model, a number of the specific characteristics of discrete contact (the rigidity of the joint of rough bodies, the real area of contact) are studied and, also, the wear to roufhness (microasperites of real surfaces) is considered. the results are compared with know experimental regularities which are interpreted on the basis of this model. 相似文献
990.
本文探索了知识挖掘和粗集理论的基本原理与方法,阐述了基于粗集理论知识挖掘的实现方法,介绍了该方法在工程中的应用。 相似文献