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151.
Zhou WANG Rong LAI Min PENG Saili ZHENG Lianyun LI Kejia ZHU Xianfang XU Liuping CHEN Jianxin SHI 《大学化学》2018,33(10):39-44
A survey about students' laboratory safety and environmental protection consciousness was performed in the freshmen majored in chemistry at Sun Yat-Sen University. Results showed that laboratory safety and environmental protection consciousness of most students' are weak. After analyzing the reasons, we put forward some suggestions. Cultivating students' laboratory safety and environmental protection consciousness should be carried out from several aspects such as emphasizing and regulating from school level, training in laboratory teaching, maintaining good cultural atmosphere of laboratory, as well as providing perfect laboratory safety and environmental protection facilities. We should guide students to actively learn knowledge and skills of laboratory safety and environmental protection in order to develop their good behavior and raise their consciousness. 相似文献
152.
鉴于当前学生化学意志素质缺乏的问题,探讨以认知、情绪唤醒、情感、意志为主控目标,在预习、尝试学习、交错搭配合作学习中,开展CAFP教学研究,以促成情意因素对认知的调动、动力、强化等功能。 相似文献
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154.
多媒体教学在高校教学中得到了广泛的应用,体现了许多优点,但在多媒体教学过程中也暴露了很多问题,文中分析了本校多媒体教学的现状,并针对存在的问题提出了改进的方法,只有科学、合理地运用多媒体教学手段,才能充分发挥其在高等教学中的作用. 相似文献
155.
K. Adamy 《Numerical Functional Analysis & Optimization》2013,34(7-8):757-783
The linearized shallow water equations are discretized in space by a finite volume method and in time by an implicit Euler scheme. Stability and convergence of the scheme are proved. 相似文献
156.
D. Shakti 《Journal of Difference Equations and Applications》2018,24(7):1185-1196
In this article, we consider a system of nonlinear singularly perturbed differential equations with two different parameters. To solve this system, we develop a weighted monotone hybrid scheme on a nonuniform mesh. The proposed scheme is a combination of the midpoint scheme and the upwind scheme involving the weight parameters. The weight parameters enable the method to switch automatically from the midpoint scheme to the upwind scheme as the nodal points start moving from the inner region to the outer region. The nonuniform mesh in particular the adaptive grid is constructed using the idea of equidistributing a positive monitor function involving the solution gradient. The method is shown to be second order convergent with respect to the small parameters. Numerical experiments are presented to show the robustness of the proposed scheme and indicate that the estimate is optimal. 相似文献
157.
目前高校实验教学主要存在实验室管理落后、实验效果差、与社会发展脱节、实验室利用率低等问题,本文对如何解决实验教学中出现的问题进行了探讨并给出了解决方案。 相似文献
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Based on Galois Field (GF(q)) multiplicative group, a new coding scheme for Quasi-Cyclic Low-Density Parity-Check (QC-LDPC) codes is proposed, and the new coding scheme has some advantages such as the simpler construction, the easier implementation encoding, the lower complexity of the encoding and decoding, the more flexible adjustment of the code length as well as the code rate and so forth. Under the condition of considering the characteristics of optical transmission systems, an irregular QC-LDPC (3843,3603) code to be suitable for optical transmission systems is constructed by applying the proposed new coding scheme. The simulation result shows that the net coding gain (NCG) of the irregular QC-LDPC (3843,3603) code is respectively improved 2.14 dB, 1.19 dB, 0.24 dB and 0.14 dB more than those of the classic RS (255,239) code in ITU-T G.975, the LDPC (32640,30592) code in ITU-T G.975.1, the regular SCG-LDPC (3969,3720) code constructed by the Systematically Constructed Gallager (SCG) coding scheme and the regular QC-LDPC (4221,3956) code at the bit error rate (BER) of 10-8. Furthermore, all the five codes have the same code rate of 93.7%. Therefore, the irregular QC-LDPC (3843,3603) code constructed by the proposed new coding scheme has the more excellent error-correction performance and can be better suitable for optical transmission systems. 相似文献