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41.
Yang Cheng-Hsing Weng Chi-Yao Lin Yih-Kai Liu Kuan-Liang 《Multimedia Tools and Applications》2017,76(22):23699-23720
Multimedia Tools and Applications - Reversible data hiding based on prediction methods is a data hiding technique wherein secret bits can be efficiently hidden into cover images. In this paper, we... 相似文献
42.
Multimedia Tools and Applications - Data hiding is a technique that embeds a cluster of secret messages into the original image. The image with secret messages can be distributed on the Internet... 相似文献
43.
交流阻抗法测定锂离子电池正极材料的导电率 总被引:1,自引:0,他引:1
采用交流阻抗法测定了3种锂离子电池正极材料LiCoO2,LiMn2O4和LiFePO4的电子导电率、离子导电率和材料电导率.结果表明,LiCoO2材料的电导率较高,含有聚阴离子基团LiFePO4材料的电子电导率和离子电导率均较低. 相似文献
44.
基于构件的软件工程及其测试、维护和实践 总被引:7,自引:0,他引:7
论述了基于构件的软件工程(CBSE)的基本思想。并对其带来的测试和维护上的新问题及解决方案进行了探讨。最后给出所开发的视频编码软件包的例子。 相似文献
45.
Acoustic emission (AE) sensors have been fabricated using polarized polyvinylidene fluoride/trifluoroethylene (P(VDF-TrFE)) piezoelectric copolymer films. The acoustic and electromechanical properties of the copolymers have been determined using the ultrasonic immersion technique and the resonance technique, respectively. The P(VDF-TrFE) AE sensors have been calibrated according to the ASTM standard and evaluated for potential application in the detection of AE in glass fiber reinforced polypropylene (GFPP). A ceramic AE sensor also has been fabricated using lead zirconate titanate (PZT) 7A piezoelectric ceramic and its sensitivity and performance are reported as well. The copolymer sensors do not show resonance peaks of the ceramic sensor and have adequate sensitivity. They can reproduce AE signals accurately without giving artifacts and have potential use in commercial AE systems. 相似文献
46.
P.C-H. Chan D.G. Retzloff R. Mohamed B. Berdouzi C. Chicone D. Offin 《Chemical Engineering Communications》1987,57(1):105-138
The dynamical behavior for two parallel reactions in a continuous stirred tank reactor (CSTR) is considered. The global maximum number of steady states is five. Stability conditions are obtained. When the steady state is unique and unstable, a circulating attractor is proven to exist. The orbit structure is numerically found to consist of periodic orbits and chaotic behavior. 相似文献
47.
48.
单正义 《山东电力高等专科学校学报》2006,9(2):15-17,21
随着我国社会经济的进一步转型,如何更有效地进行诚信教育已成为高校德育教育的一项重要课题。本文从诚信的内涵出发,以大学生诚信现状为切入点,并在此基础上对大学生诚信缺失的现象和存在的问题进行深入分析,提出构建高校学生诚信体系的对策或建议。 相似文献
49.
Tam Sing-Fai; Man David Wai-Kwong; Chan Yuk-Piu; Sze Pan-Ching; Wong Chi-Ming 《Canadian Metallurgical Quarterly》2005,50(3):285
Objective: To evaluate the effectiveness of a 2-D virtual reality (VR) program for training people with intellectual disabilities to shop. Study Design: Pretest and posttest quasi-experimental design. Participants: Sixteen persons with intellectual disabilities (age 17-23 years; IQ = 40-54). Intervention: A VR program or a conventional program training them in supermarket-shopping skills. Main Outcome Measure: Checklist for supermarket-shopping skills. Results: Participants in both training groups showed significant improvement. There was no significant difference in effectiveness between the two methods. Conclusions: The VR program appears effective in training people with intellectual disabilities in an important community living skill. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
50.
This paper describes an experimental investigation into the performance and lubrication failure mechanism of precise angular-contact ball bearings treated with MoS2-sputtered film, etc. As an important executive component of various spacecrafts, there are some strict requirements on the lubrication performance of angular-contact ball bearing, but the related experimental data are rare to see in literatures. In this experiment, the lubrication performances of MoS2-sputtered ball bearing pairs were evaluated by using lifetime test as a main method, and the topographies and compositions of working surfaces were investigated through SEM, AES and EDS. The systematical experiment results reveal that the degradation and failure process of solid lubrication for such ball bearing is divided into three stages with different characters. A supposed failure mechanism has been proposed. An improved lubrication treatment based on above mechanism was conducted for the precise ball bearings, and a later test showed that long endurance life with more than 108 revolutions has been reached. 相似文献