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81.
多媒体技术是一项很好的现代教学手段,可以有效的改善高职院校《毛泽东思想和中国特色社会主义理论体系概论》传统教学手段的缺陷,但应该科学、合理的运用多媒体技术,充分发挥其教学优越性,本文从多媒体课件的运用理念、制作要求和操作使用三个方面,详细分析了多媒体技术在概论课教学中的应用,形成了深入的认识。 相似文献
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Risk Allostasis Theory states that drivers seek to maintain a feeling of risk within a preferred range [Fuller, R., 2008. What drives the driver? Surface tensions and hidden consensus. In: Keynote at the 4th International Conference on Traffic and Transport Psychology, Washington, DC, August 31–September 4, 2008]. Risk Allostasis Theory is the latest version of Task-Difficulty Homeostasis theory, and is in part based on the findings of experiments where participants were asked to rate the task difficulty, feeling of risk and chance of collision of scenes shown in digitally altered video clips [Fuller, R., McHugh, C., Pender, S., 2008b. Task difficulty and risk in the determination of driver behaviour. Revue européenne de psychologie appliqée 58, 13–21].The focus of the current research was to expand upon the previous video based experiments using a driving simulator. This allowed participants to be in control of the vehicle rather than acting as passive observers, as well as providing additional speed cues. The results support previous findings that ratings of task difficulty and feeling of risk are related, and that they are also highly related to ratings of effort and moderately related to ratings of comfort and habit. However, the linearly increasing trend for task difficulty and feeling of risk described by the previous research was not observed: instead the findings of this experiment support a threshold effect where ratings of risk (feeling of and chance of loss of control/collision), difficulty, effort, and comfort go through a period of stability and only start to increase once a certain threshold has been crossed. It is within the period of stability where subjective experience of risk and difficulty is low, or absent, that drivers generally prefer to operate. 相似文献
85.
李沫 《材料科学与工程学报》2011,(6)
威廉.大内的"Z理论"是一本研究美日管理差异的经典之作。在这本著作出版后的三十年管理实践和理论发展后,今天再看Z理论可以发现其中的诸多缺陷。但是Z理论中所采用的比较管理学的研究方法和研究路径对构建中国管理模式具有重大的启示作用。 相似文献
86.
Tao Li Chunlan Zhou Zhengang Liu Wenjing Wang 《International Communications in Heat and Mass Transfer》2011,38(8):1041-1043
In this paper, a numerical model of nanosecond laser ablation of crystalline silicon has been established. Based on the highly nonlinear model of heat transfer and phase change in crystalline silicon after absorbing laser light, heat transfer equation is solved by using finite element method implemented in ANSYS. The simulation of ablation depth of crystalline silicon is obtained under different conditions of laser fluence and pulse overlap. Comparing with the ablation morphology obtained from SEM observations, the computational results and experimental data show good agreement. 相似文献
87.
Ya Ping Chang Author VitaeDong Hong ZhuAuthor Vitae 《Computers in human behavior》2011,27(5):1840-1848
Prior experience is an important determinant factor of individual behavior. This paper developed a theoretical model to predict the adoption intention of pre-adopters and post-adopters on social networking sites based on the theory of planned behavior. Using data from online surveys of netizens in China, the proposed model was tested in the context of pre-adoption and post-adoption by using the Partial Least Squares (PLS) technique. Then, multi-groups analysis was explored to compare the difference between the two groups. The results show that attitude, subjective norm and perceived behavior control have significant effect on the adoption intention of pre-adopters and post-adopters, and there is no significant difference between the two groups. In addition, information, meeting new people, and conformity motivations have the same significant effect on both groups. However, entertainment motivation has a significant effect on pre-adopters but connecting with old friends has none; in contrast, connecting with old friends has significant effect on post-adopters while entertainment motivation has no significant effect. 相似文献
88.
Karen Payne 《Landscape Research》2013,38(2):167-179
A decision support system designed to aid the planning and creation of green-space or open-space networks is described. The system relies on data describing current land cover and existing conservation lands, and may be extended to include any number of other ancillary data sources. The system incorporates algorithms developed in the fields of graph theory and operations research but also describes two new algorithms. The system demonstrates the application of existing graph theory algorithms in reserve design problems by illustrating the similarity and differences between classic graph theory problems and those faced by planning officials. Notions of connectivity and parsimony important to researchers in both fields are explicitly addressed. 相似文献
89.
用通俗的叙述对电梯的曳引理论进行了深入的解读,并推导了欧拉公式;对电梯导轨的进一步制导行程的设定也进行了深入的解读。 相似文献
90.
《国际计算机数学杂志》2012,89(5):573-590
The integer factorization problem (IFP), the finite field discrete logarithm problem (DLP) and the elliptic curve discrete logarithm problem (ECDLP) are essentially the only three mathematical problems that the practical public-key cryptographic systems are based on. For example, the most famous RSA cryptosystem is based on IFP, the US government's Digital Signature Standard, DSS, is based on DLP, whereas the ECC (Elliptic Curve Cryptography) and Elliptic Curve Digital Signature Algorithm (ECDSA) are based on ECDLP. The security of such cryptographic systems relies on the computational intractability of these three mathematical problems. In this paper, we shall present a survey of various methods for solving the IFP/DLP and particularly the ECDLP problems. More specifically, we shall first discuss how the index calculus as well as quantum algorithms can be used to solve IFP/DLP. Then we shall show why the index calculus cannot be used to solve ECDLP. Finally, we shall introduce a new method, xedni calculus , due to Joseph Silverman, for attack ECDLP; some open problems and new research directions, will also be addressed. 相似文献