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1.
The authors argue that the solution of urban problems requires resources and powers far beyond those available to most local governments. Only through partnerships of all relevant actors—public officials, businessmen and neighborhood residents—can such issues be dealt with. Yet, partnerships are neither simple nor inevitable. They require hard work and usually the development of the capacities of all involved. Such capacity building for partnerships is on three levels: the development of the individual capacity to play partnership roles; the creation of interactive partnerships operating as local problem solvers; and the fostering of inter-partnership networks. Neighborhoods are seen as the building blocks of cities, serving as a locality of scale upon which the citizen can base his concerns and actions and within which partnerships can operate effectively. Specific recommendations are made, utilizing this policy context to build capacity for partnerships at the neighborhood level, particularly with regard to the Intergovernmental Personnel Act.  相似文献   
2.
Open problems posed by Klir and Wierman (1998) for a nonspecificity measure are solved; the measure is proven additive, and its extension to nonconvex sets given. Several different proofs of additivity are given, to suggest certain techniques of wider applicability in system problems and to motivate further research possibihties. A study is initiated to refine nonspecificity separately to each dimension k≤n for the bodies residing in Rn.  相似文献   
3.
Measures of two types of uncertainty that coexist in the Dempster-Shafer theory are overviewed. A measure of one type of uncertainty, which expresses nonspecificity of evidential claims, is well justified on both intuitive and mathematical grounds. Proposed measures of the other types of uncertainty, which atlempt to capture conflicts among evidential claims, are shown to have some deficiencies. To alleviate these deficiencies, a new measure is proposed. This measure, which is called a measure of discord, is not only satisfactory on intuitive grounds, but has also desirable mathematical properties. A measure of total uncertainty, which is defined as the sum of nonspecificity and discord, is also discussed. The paper focuses on conceptual issues. Mathematical properties of the measure of discord are only slated; their proofs are given in a companion paper.15  相似文献   
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Solar cells, powering satellites and other space vehicles, can suffer substantial degradation in performance by electron and proton irradiation experienced in orbit. These effects are first described, and the behaviour of silicon solar cells compared with cells of gallium arsenide and indium phosphide, and the more recent thin film type cells. In particular, the paper will discuss the phenomenon of ‘photon degradation’ in silicon cells, and recent progress in understanding the defect mechanisms responsible for this effect occurring after illumination of irradiated cells. Strategies for improving the radiation resistance of silicon solar cells, including the use of ‘defect gettering’ will be discussed, while the effects of annealing radiation damage will be outlined. Finally, the paper will seek to identify areas where an improved understanding of defect behaviour is necessary to produce further improvements in performance. In particular, it highlights the need for fundamental studies of advanced solar cell structures and materials, including CIS cells, where significant improvement in radiation tolerance has been found.  相似文献   
7.
ABSTRACT— The activity of 2 radiation-surviving and strongly proteolytic strains of Pseudomonas and Achromobacter were compared to the activity of 2 lesser active strains of Neisseria and Bacillus in fresh oysters during iced (32°F) and refrigerated (40°F) storage for 15 days. Radiation doses used for the oysters were 100 and 800 krad. The activity of the former bacteria was higher than that of the latter 2 at both temperatures and radiation doses. Neither the nonirradiated nor the irradiated uninoculated oysters displayed significant increases in proteolytic activity when they were ice-stored for 15 days, but storage at 40°F for the same period resulted in significant activity increases in the nonirradiated. This emphasizes irradiation and storage temperature as related factors. A slight decrease in pH at 15 days in both nonirradiated and 100 krad-irradiated oysters corresponded to the increase in bacterial numbers.  相似文献   
8.
Measures of information based on fuzzy sets (possibility distributions) had been defined only for finite domains of discourse. This paper presents a method of defining such information functions on a continuous universe of discourse—a domain which is a measurable space of measure 1. The method is based on the concept of “rearangement” of a function, used in lieu of sorting discrete possibility values. For technical reasons, it is preferred to express information value as information distance to the most “uninformed” (constant possibility 1) distribution. The final form of the information for possibility distribution f is

The paper then discusses related information distances and approximations using discrete information functions.  相似文献   

9.
Lucifer, a direct predecessor of the DES algorithm, is a block-cipher having a 128 bit block size and 128 bit key length. Its general design principles and properties are described and discussed. A simple FORTRAN program is presented which implements the algorithm, providing a modern, secure cryptographic algorithm that can be used in personal computers. Lucifer is of special interest because it is in the same class of product ciphers as DES but is much simpler. Study of Lucifer may reveal cryptanalytic methods that can be applied to DES.  相似文献   
10.
ABSTRACT

The segmented secondary linear reluctance motor is analyzed using a permeance function approach. The basic assumptions are iron linearity and current excitation. The resulting analytical equations are implemented for numerical computation. The numerical results are compared with experimental results which are obtained from a 2 pole, 37 m/s laboratory model linear reluctance motor.  相似文献   
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