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排序方式: 共有1075条查询结果,搜索用时 15 毫秒
1.
LeeSiewWei 《水利水电快报》2002,23(19):1-5
在英国伦敦多克兰斯轻便铁路刘易舍姆延长线(DLR-LWE)双隧道掘进工程中,在敏感建筑物下进行了补偿灌浆,以防止隧道开挖引起的过度沉降。但是,过度灌浆也会对隧道下部施加超越。介绍了由隧道掘进承包商所编辑的关于地面和建筑物沉降以及由补偿灌浆引起的隧道衬砌变形的详细现场监测数据。 相似文献
2.
W. L. Siew F. C. H. Oh A. S. H. Ong 《Journal of the American Oil Chemists' Society》1985,62(6):1036-1039
Some of the factors affecting cloud point determination of palm oleins are described. These are the type of container used, method of stirring, rate of stirring and bath temperature. The repeatability and reproducibility standard deviations of the method are determined from collaborative trials. Recommendations for the test are made to reduce the large variations among laboratories. 相似文献
3.
The notion of pseudorandomness is the theoretical foundation on which to consider the soundness of a basic structure used in some block ciphers. We examine the pseudorandomness of the block cipher KASUMI, which will be used in the next‐generation cellular phones. First, we prove that the four‐round unbalanced MISTY‐type transformation is pseudorandom in order to illustrate the pseudorandomness of the inside round function FI of KASUMI under an adaptive distinguisher model. Second, we show that the three‐round KASUMI‐like structure is not pseudorandom but the four‐round KASUMI‐like structure is pseudorandom under a non‐adaptive distinguisher model. 相似文献
4.
The PBD-Closure of Constant-Composition Codes 总被引:3,自引:0,他引:3
Yeow Meng Chee Ling A.C.H. San Ling Hao Shen 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2007,53(8):2685-2692
We show an interesting pairwise balanced design (PBD)-closure result for the set of lengths of constant-composition codes whose distance and size meet certain conditions. A consequence of this PBD-closure result is that the size of optimal constant-composition codes can be determined for infinite families of parameter sets from just a single example of an optimal code. As an application, the sizes of several infinite families of optimal constant-composition codes are derived. In particular, the problem of determining the size of optimal constant-composition codes having distance four and weight three is solved for all lengths sufficiently large. This problem was previously unresolved for odd lengths, except for lengths seven and eleven. 相似文献
5.
Chee -Keng Yap 《Algorithmica》1988,3(1-4):279-288
We give a parallel method for triangulating a simple polygon by two (parallel) calls to the trapezoidal map computation. The method is simpler and more elegant than previous methods. Along the way we obtain an interesting partition of one-sided monotone polygons. Using the best-known trapezoidal map algorithm, ours run in timeO(logn) usingO(n) CREW PRAM processors. 相似文献
6.
Crystallization of palm oil with and without solvent was carried out over a temperature range of 10–25°C. The yields of olein,
the diglyceride contents, and compositions of the stearin and olein phases were determined by thin-layer and gas-liquid chromatography.
The three major diglycerides, analyzed as C32, C34, and C36, are mainly dipalmitoyl glycerol, palmitoyloleoyl glycerol, and dioleoyl glycerol. In crystallization without solvent, C32 (PP) had a strong affinity for the stearin fraction and C36 diglycerides concentrated in the olein phase. The partition coefficient of diglycerides between the olein and stearin phases
was temperature-dependent and was influenced by the type of solvent used. Although solvent enhances the diglyceride partition
into the olein phase, partitioning is more effective at low temperatures and with acetone as the solvent for fractionation. 相似文献
7.
Computer-mediated communication has become a popular platform for identity construction and experimentation as well as social interaction for those who identify as lesbian, gay, bisexual or transgender (LGBT). The creation of user-generated videos has allowed content creators to share experiences on LGBT topics. With bullying becoming more common amongst LGBT youth, it is important to obtain a greater understanding of this phenomenon. In our study, we report on the analysis of 151 YouTube videos which were identified as having LGBT- and bullying-related content. The analysis reveals how content creators openly disclose personal information about themselves and their experiences in a non-anonymous rhetoric with an unknown public. These disclosures could indicate a desire to seek friendship, support and provide empathy. 相似文献
8.
Kim Kihyeun Son Myungwoo Pak Yusin Chee Sang-Soo Auxilia Francis Malar Lee Byung-Kee Lee Sungeun Kang Sun Kil Lee Chaedeok Lee Jeong Soo Kim Ki Kang Jang Yun Hee Lee Byoung Hun Jung Gun-Young Ham Moon-Ho 《Nano Research》2018,11(7):3957-3957
Nano Research - The order of the authors in the original version of this article was unfortunately incorrect on the first page and the first page of the ESM. Instead of Myungwoo Son1, Yusin Pak1,... 相似文献
9.
Thermal actuated sliders are being widely used in today’s hard disk drive industry for its advantages of easier control of flying height (FH) and less risk of contacts with the disk. This article uses a coupled-field analysis method, which includes an air bearing model, a heat transfer model and a thermal-structural finite element model to investigate the FH changes of thermal actuated sliders at various environmental conditions. The mechanism of water vapour’s contribution to air bearing pressure loss is explained and a new humidity model is proposed to calculate this pressure loss. The temperature effects are also considered in the simulation models. It is observed that the environmental temperature and humidity have significant effects on slider’s FH changes, but their effects on the thermal protrusion height are limited. A humidity sensitivity study is also made and the results are discussed. It is found that the slider with thermal protrusion on its trailing pad will be more sensitive to the humidity. Besides air bearing stiffness, some other factors such as peak pressure, protrusion shape and air bearing surface (ABS) design will also contribute to the slider’s humidity sensitivity. 相似文献
10.