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121.
BRIAN J. WINKEL 《Cryptologia》2013,37(3):247-251
Abstract The problem of when the Russians started to read the German cipher machine ENIGMA still remains unsolved. A Russian document presented recently in a history of the GRU in the time of the Great patriotic War offers a new light on the problem. In November 1942 the Russians were able to begin reading ENIGMA on a daily basis and were thinking about automating the process. We do not know if incorporating the GRU cryptanalysts in the parallel section of the NKVD helped in the brilliant defeat of the Germans during the “Uran” and “Saturn” operations at Stalingrad, but we suppose so. The Russian solution of the ENIGMA ciphers could be linked with the traitors working at Station X (Bletchley Park) and in Military Intelligence. 相似文献
122.
This paper analyses total cost optimization for a single pass turning operation for a given feed and depth of out taking into consideration penalty cost for due date violation and in-process inventory cost. These costs are in addition to the two cost components, viz., machine and operator cost, and tool consumption cost, which are usually considered in studies on machining economics. In earlier work in machining economics, in-process inventory cost and penalty cost for due date violation have not been considered. Since these cost components are usually present in an industrial environment consideration of these costs makes the problem realistic. 相似文献
123.
124.
A METHOD FOR DETERMINING THE CONVECTIVE HEAT TRANSFER COEFFICIENT DURING IMMERSION FRYING 总被引:2,自引:0,他引:2
The convective heat transfer coefficient is a useful parameter in characterizing heat flow across a fluid/solid interface when the fluid flow field is complex and solution of the coupled transport equations impractical. While convective heat transfer coefficient values for many unit operations have been tabulated, the boiling phase of immersion frying has not been quantified. The objective of this study was to develop a laboratory method for the measurement of the convective heat transfer coefficient during immersion frying. The method that was developed was applied to the immersion frying of potato cylinders at an oil temperature of 180C. The convective heat transfer coefficient was initially 300 W/m2K, it increased sharply to 1100 W/m2K, and gradually decreased to 300 W/m2K over the duration of the process. Use of this new method will allow the study of the effects of oil temperature, oil quality, product shape/size, and product quality on heat transfer coefficients. 相似文献
125.
An analysis of helium and neon transport in vitreous silica is consistent with a statistically distributed structure of the random network. The jump distance, d , for diffusion in common borosilicate glass is greater than in vitreous silica due to the additional modifier ions, Na+ . The addition of Na+ or K+ to a silicate structure produces an increase in d . The vibrational frequencies for a gas atom in a "doorway" ( v *) and in a solubility site ( v ) indicate structural trends such as phase separation. 相似文献
126.
Abstracts are not published in this journal 相似文献
127.
Tables of efficiency for a set of machines regularly patrolled by one operator have been produced. The theoretical basis of the tables has been described elsewhere. The numerical results show that unidirectional patrolling produces a small but consistent advantage over bi-directional patrolling, both in the case of manual repairs and automatic repairs which may not always be successful. This has implications for the design and layout of the machines on the factory floor. In addition, the tables can be used to determine the optimum number of machines to allocate to an operator. 相似文献
128.
BRIAN HABERLIN 《计算机光盘软件与应用》2008,(2):32-37
为你展示怎样通过将不同人物的身体部分组合在一起,来制作一个自然的怪兽。现在该你戴上手术手套变成Frankenstein医生了…… 相似文献
129.
The fading of a series of phenylazo–β–naphthol dyes on polypropylene by exposure to either long– or short–wavelength ultraviolet radiation and under nitrogen and oxygen atmospheres, respectively, is reported. The half–lives and relative rates of fading of the dyes were calculated at the wavelength of maximum absorption of the hydrazone band and the hydrazone–azo ratios of the dyes were determined on polypropylene and in ethanol. The relative rates of fading were plotted against the appropriate Hammett constants for the substituents. In general, a linear relation was observed. The graphs had positive slopes, but negative slopes were also obtained with the dyes bearing electropositive groups. Graphs of relative rates of fading against hydrazone?azo ratio were also drawn. The results were generally similar to those obtained with the plots of Hammett constants, but correlation was better. The results indicate that, on polypropylene, the most important fading mechanism for the hydrazone form of the dye is reductive, although there is evidence that oxidation may occur, especially in the presence of oxygen. 相似文献
130.
This paper discusses issues raised in the design of a dynamically generated Web-based natural history encyclopedia for children. The novelty of our proposal is the dynamic creation of encyclopedia entries using domain-specific middleware to access biological and ecological readers (users) with tailored reports summarizing information drawn from distributed datasets. A prerequisite, however, is a domain-dependent standardized data labeling system. Our project will piggyback on the host of projects currently developing metalabeling frameworks to dynamically create stories which are peopled by creatures from biological collections, are set in locations of local or other interest to the site visitor, and use scenarios based on relevant ecosystems. The underlying scientific databases provide a much broader range of subject matter (species and locations) that would not otherwise be feasible and alleviate content maintenance problems that beset community Web sites or professional encyclopedias. To incorporate such information in the sorts of format expected in a children's encyclopedia involves developing sets of “story” templates, rules for selection of a template, and rules for design of the multimedia presentation of the story. It also requires comprehensive labeling systems for data in the scientific databases. 相似文献