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连带责任加重了个别相关人的责任,因此需要谨慎适用.建设工程领域存在扩张适用连带责任的趋势,是立法层面功利主义的表象. 相似文献
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关于狭义相对论的修正以及新引力理论的方案 总被引:2,自引:0,他引:2
张操 《北京石油化工学院学报》2006,14(4):39-45
相对论存在一定的局限性.狭义相对论适用于电磁的相互作用.没有强有力的证据显示狭义相对论也适用于其它3种基本相互作用.至少在弱相互作用中,中微子可能是超光速粒子.物理学需采取多种时间的定义,一种推广伽利略变换的时间值得进一步研究.广义相对论很大程度上是一种数学理论.作为物理学的引力理论,它存在很多基本缺陷.检验广义相对论一些天文实验,误差很大,需要重新分析.笔者将讨论一种新引力理论的方案.它的引力场方程与电磁理论的麦克斯韦方程十分相似. 相似文献
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Kersten Alan W.; Meissner Christian A.; Lechuga Julia; Schwartz Bennett L.; Albrechtsen Justin S.; Iglesias Adam 《Canadian Metallurgical Quarterly》2010,139(4):638
Three experiments provide evidence that the conceptualization of moving objects and events is influenced by one's native language, consistent with linguistic relativity theory. Monolingual English speakers and bilingual Spanish/English speakers tested in an English-speaking context performed better than monolingual Spanish speakers and bilingual Spanish/English speakers tested in a Spanish-speaking context at sorting novel, animated objects and events into categories on the basis of manner of motion, an attribute that is prominently marked in English but not in Spanish. In contrast, English and Spanish speakers performed similarly at classifying on the basis of path, an attribute that is prominently marked in both languages. Similar results were obtained regardless of whether categories were labeled by novel words or numbered, suggesting that an English-speaking tendency to focus on manner of motion is a general phenomenon and not limited to word learning. Effects of age of acquisition of English were also observed on the performance of bilinguals, with early bilinguals performing similarly in the 2 language contexts and later bilinguals showing greater contextual variation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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In a wireless network, node failure due to either natural disasters or human intervention can cause network partitioning and other communication problems. For this reason, a wireless network should be fault tolerant. At present, most researchers use k-connectivity to measure fault tolerance, which requires the network to be connected after the failure of any up to k-1 nodes. However, wireless network node failures are usually spatially related, and particularly in military applications, nodes from the same limited area can fail together. As a metric of fault-tolerance, k-connectivity fails to capture the spatial relativity of faults and hardly satisfies the fault tolerance requirements of a wireless network design. In this paper, a new metric of fault-tolerance, termed D-region fault tolerance, is introduced to measure wireless network fault tolerance. A D-region fault tolerant network means that even after all the nodes have failed in a circular region with diameter D, it still remains connected. Based on D-region fault tolerance, we propose two fault-tolerant topology control algorithms--the global region fault tolerance algorithm (GRFT) and the localized region fault tolerance algorithm (LRFT). It is theoretically proven that both algorithms are able to generate a network with D-region fault tolerance. Simulation results indicate that with the same fault tolerance capabilities, networks based on both GRFT and LRFT algorithms have a lower transmission radius and lower logical degree. 相似文献