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31.
对流方程的交替分组显示方法 总被引:5,自引:1,他引:4
提出了求解对流方程初边值问题绝对稳定的二阶精度交替分组显示方法.模型问题的数值结果表明,本方法忧于陈景良和陆金甫的分组显示方法. 相似文献
32.
This investigation was prompted by Asch's (1952) discussion of the personal and social significance of yielding to group pressure. For the person, yielding requires the inhibition of overt and perhaps implicit responses to objective situational requirements. For the group, malignant processes may arise and develop, unchecked by those members in whom goals of personal security predominate over group goals. In the present study, the view was taken that both meanings of yielding are assigned positive value in two separate ideologies concerning the group-individual relation. One of these is termed "conformity" and the other is "rugged individualism." In the study, group pressure was simulated by announcing bogus group judgments to small groups of Ss whose apparent task was to match one of three lines of variable length with a standard line. Questionnaires were used to measure variables, which were: the ideology of conformity (IC), the ideology of rugged individualism (RI), ethnocentrism (E), and authoritarianism (F). The questionnaires were administered to 91 college students, both day school and evening. It was found that the correlation with the F scale was .48 (P 相似文献
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魅力型领导与团队学习:团队目标明确度的缓冲效应 总被引:1,自引:0,他引:1
本研究采用分组回归方法,以89支学生研究项目团队作为研究对象,考查魅力型领导与团队学习间的影响关系;并检验了团队目标的明确程度对魅力型领导和团队学习间关系所起的缓冲效应.结果表明,魅力型领导有助于团队学习;另一方面,当团队目标相对明确时,魅力型领导对团队学习的积极影响效应才较为显著;而当团队目标相对不明确时,魅力型领导... 相似文献
35.
分析了一个基于中国剩余定理的群签名方案,指出此方案并不安全:任何一个群成员或已被撤销的群成员都可以完全攻破此方案。针对该安全缺陷提出了一个改进的新方案。分析表明,该方案不仅可以在不改变其他群成员密钥的情况下有效地增加和撤销群成员,而且具有不可伪造性、防陷害攻击、抗联合攻击等性质。 相似文献
36.
基于成组技术的电机制造CAPP系统 总被引:1,自引:1,他引:0
鲁昌国 《辽宁石油化工大学学报》2008,28(2):58-60
根据电机厂产品的特殊性及电机零件结构特点,自行设计了具有一定针对性的13位分类编码系统,通过工艺设计标准化、自动化过程,成功开发一套适合电机生产特点的DJ-1CAPP系统,解决电机生产过程中工艺设计的瓶颈问题。 相似文献
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In most (t,n)-Multi-secret sharing ((t,n)-MSS) schemes, an illegal participant, even without any valid share, may recover secrets when there are over t participants in secret reconstructions. To address this problem, the paper presents the notion of Group ori-ented (t,m,n)-multi-secret sharing (or (t,m,n)-GOMSS), in which recovering each secret requires all m (n ≥ m ≥ t) participants to have valid shares and actually participate in secret reconstruction. As an example, the paper then pro-poses a simple (t,m,n)-GOMSS scheme. In the scheme, every shareholder has only one share; to recover a secret, m shareholders construct a Polynomial-based randomized component (PRC) each with the share to form a tightly coupled group, which forces the secret to be recovered only with all m valid PRCs. As a result, the scheme can thwart the above illegal participant attack. The scheme is simple as well as flexible and does not depend on conventional hard problems or one way functions. 相似文献
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40.
Oksana V. Salomatina Aleksandra V. Senkova Arseny D. Moralev Innokenty A. Savin Nina I. Komarova Nariman F. Salakhutdinov Marina A. Zenkova Andrey V. Markov 《International journal of molecular sciences》2022,23(11)
It is known that epoxide-bearing compounds display pronounced pharmacological activities, and the epoxidation of natural metabolites can be a promising strategy to improve their bioactivity. Here, we report the design, synthesis and evaluation of biological properties of αO-SM and βO-SM, novel epoxides of soloxolone methyl (SM), a cyanoenone-bearing derivative of 18βH-glycyrrhetinic acid. We demonstrated that the replacement of a double-bound within the cyanoenone pharmacophore group of SM with α- and β-epoxide moieties did not abrogate the high antitumor and anti-inflammatory potentials of the triterpenoid. It was found that novel SM epoxides induced the death of tumor cells at low micromolar concentrations (IC50(24h) = 0.7–4.1 µM) via the induction of mitochondrial-mediated apoptosis, reinforced intracellular accumulation of doxorubicin in B16 melanoma cells, probably by direct interaction with key drug efflux pumps (P-glycoprotein, MRP1, MXR1), and the suppressed pro-metastatic phenotype of B16 cells, effectively inhibiting their metastasis in a murine model. Moreover, αO-SM and βO-SM hampered macrophage functionality in vitro (motility, NO production) and significantly suppressed carrageenan-induced peritonitis in vivo. Furthermore, the effect of the stereoisomerism of SM epoxides on the mentioned bioactivities and toxic profiles of these compounds in vivo were evaluated. Considering the comparable antitumor and anti-inflammatory effects of SM epoxides with SM and reference drugs (dacarbazine, dexamethasone), αO-SM and βO-SM can be considered novel promising antitumor and anti-inflammatory drug candidates. 相似文献