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991.
采用基于密度泛函理论的第一性原理计算方法,系统研究了典型立方结构合金相LaMgX4(X=Co, Ni, Cu)的力学特性和热力学特性。根据广义胡可定律计算了合金相的单晶弹性常数;根据单晶弹性常数和Hershey’s averaging方法计算了合金相的多晶弹性模量、泊松比、Zener各向异性因子和德拜温度。采用基于准谐近似的Gibbs2代码计算了LaMgX4(X=Co, Ni, Cu)合金相的吉布斯自由能、熵和等体热容与温度的关系。LaMgNi4的计算结果与其他文献计算结果及实验结果符合的很好。结果表明:LaMgX4 (X= Co, Ni, Cu)合金均为延展性、塑性和弹性各向异性材料。德拜温度按以下顺序递减:LaMgNi4>LaMgCu4>LaMgCo4。 相似文献
992.
The degradation and recovery processes are multi-scale phenomena in many physical, engineering, biological, and social systems, and determine the aging of the entire system. Therefore, understanding the interplay between the two processes at the component level is the key to evaluate the reliability of the system. Based on the principle of maximum entropy, an approach is proposed to model and infer the processes at the component level, and is applied to repairable and non-repairable systems. By incorporating the reliability block diagram, this approach allows for integrating the information of network connectivity and statistical moments to infer the hazard or recovery rates of the degradation or recovery processes. The overall approach is demonstrated with numerical examples. 相似文献
993.
Hongming Zhu Xiaowen Wang Yizhi Jiang Hongfei Fan Bowen Du Qin Liu 《Entropy (Basel, Switzerland)》2021,23(5)
Instance matching is a key task in knowledge graph fusion, and it is critical to improving the efficiency of instance matching, given the increasing scale of knowledge graphs. Blocking algorithms selecting candidate instance pairs for comparison is one of the effective methods to achieve the goal. In this paper, we propose a novel blocking algorithm named MultiObJ, which constructs indexes for instances based on the Ordered Joint of Multiple Objects’ features to limit the number of candidate instance pairs. Based on MultiObJ, we further propose a distributed framework named Follow-the-Regular-Leader Instance Matching (FTRLIM), which matches instances between large-scale knowledge graphs with approximately linear time complexity. FTRLIM has participated in OAEI 2019 and achieved the best matching quality with significantly efficiency. In this research, we construct three data collections based on a real-world large-scale knowledge graph. Experiment results on the constructed data collections and two real-world datasets indicate that MultiObJ and FTRLIM outperform other state-of-the-art methods. 相似文献
994.
The collision frequencies of electron-neutral-particle in weakly ionized complex plasmas with the non-Maxwellian velocity distributions are studied. The average collision frequencies of electron-neutral-particle in plasmas are accurately derived. We find that these collision frequencies are significantly dependent on the power-law spectral indices of non-Maxwellian distribution functions and so they are generally different from the collision frequencies in plasmas with a Maxwellian velocity distribution, which will affect the transport properties of the charged particles in plasmas. Numerically analyses are made to show the roles of the spectral indices in the average collision frequencies respectively. 相似文献
995.
Du Yun-Zhi Zhao Hui-Hua Zhang Li-Chun 《International Journal of Theoretical Physics》2021,60(5):1963-1971
International Journal of Theoretical Physics - Some ones have showed the first-order phase transition of the Horava-Lifshitz (HL) AdS black holes has unique characters from other AdS black holes.... 相似文献
996.
近年来,社区问答服务系统(CQA)越来越受到人们的欢迎,但随着提问规模的膨胀,获得回答的问题比重逐步降低,且答案质量无法得到保障.为了提高问答系统中问题被解答的概率,并提升答案可信度,文中提出了基于社交关系相似度的社交问答系统(SQA),主动寻找与提问者社交关系紧密且能够回答问题的用户,并提出了针对提问者与最佳回答者的推荐方法.实验结果表明,在主观性强或实时性强等问题集上,文中方法能更快地得到让提问者满意的答案. 相似文献
997.
针对现有流程偏差模式无法正确识别流程组合偏差的情况,提出一种流程组合偏差模式。该模式以构建偏差模式约束为前提,将活动替换、交换和重复偏差模式相互组合。以标准代价函数为基础,给出改进代价函数。根据组合偏差模式及改进代价函数,设计交换重复偏差模式。将交换重复偏差模式应用于签证申请流程,获得的校准结果可以识别流程中存在的偏差,验证了组合偏差模式能够有效识别流程组合偏差。 相似文献
998.
Chao Wang Yongchao Lu Hongguang Huang Fengcun Xing Lei Chen Xuebin Du Zhanhong Liu Wenjun Zhang 《地球科学学刊》2015,(3)
The large reef complexes of the Upper Permian Changxing Formation, with a significant breakthrough for petroleum exploration, are an important target for petroleum exploration in the Yu-anba area of th... 相似文献
999.
针对食品包装用户体验的度量方法,提出了基于认知心理差异的用户体验度量模型.将食品包装的用户体验作为一个流动变化的系统过程,最终的度量结果由认知结果与差异结果构成,认知结果反映用户对食品包装的实际认知,差异结果反映用户期望与实际感知之间的差距.通过度量模型找出造成用户认知差异的主要影响因素,为食品包装后期改进提供帮助. 相似文献
1000.
Gongduan Fan Jiuhong Lin Mingqian Xia Jing Luo Banghao Du Heliang Pang Zhongsen Yan 《Particle & Particle Systems Characterization》2021,38(2):2000272
Photocatalysis has attracted much attention as an emerging algae removal technology, but the inactivation performance is inevitably affected by the extracellular polymeric substance (EPS) produced by algae. In this study, a photocatalyst (Ag2O/g-C3N4) with efficient algae inactivation is adopted to investigate the interactions with EPS, and the impact of EPS on photocatalytic algae removal is studied. The results show that EPS can adhere to the surface of Ag2O/g-C3N4 by electrostatic force. The interaction with EPS decreases the surface zeta potential of the Ag2O/g-C3N4 from 7.71 to −22.3 mV with the increase in EPS concentration, and the maximum ratio of particle size increases from 825 to 1281 nm. In addition, the interaction with EPS inhibits the release of Ag+ in Ag2O/g-C3N4 by half, thus, the toxicity of metal ions will be alleviated. Meanwhile, EPS can also be degraded by Ag2O/g-C3N4, indicating that EPS can work as a radical scavenger to protect the algae cells. Without the protection of EPS, 97.8% of algae cells are inactivated after 5 h photocatalysis. Therefore, more attention should be given to the interaction between EPS and photocatalyst to promote the design and application of the photocatalytic. 相似文献