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51.
《矿业科学技术学报(英文版)》2016,26(4):571-575
The content and the caking index of the heavy,the dense medium and the loose medium components of coal,obtained by extraction and stripping with CS_2/N-methyl-2-pyrrolidinone mixed solvent(1:1 by volume),were studied and correlated with the caking property of raw coals.Images of the three group components after heat treatment were analyzed.The results show that both caking index(G) and maximum thickness of plastic layer(Y) of coals have a good linear relationship with the content of the medium component;the dense medium and the loose medium components are the two key factors to determine the caking property of raw coals-they are the source materials of fluidity and swelling of coal,respectively;the heavy component without the swelling and fluidity was cohered by the other components;two new indexes,which can extend current understanding of the caking properties,were introduced. 相似文献
52.
批判性思维是一种独特的认识技能,是一种反思能力。批判性思维是邓小平的重要思维方式,贯穿于邓小平理论的整个体系。邓小平的批判性思维是特定历史文化的产物,有其产生的历史和现实根据。邓小平运用批判性思维,在对社会主义本质、社会主义发展阶段、社会主义经济体制等问题的认识上取得了重大突破,与时俱进地实现了马克思主义的中国化,并取得了丰硕的理论成果。 相似文献
53.
邓小平思维方式是典型的批判性思维。批判性思维是邓小平理论创新的动力和源泉;邓小平批判性思维有利于确立科学的思维方式;邓小平批判性思维有利于培养求真务实的精神和开拓创新的勇气;邓小平批判性思维有助于开启思维的闸门。 相似文献
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XU Xiang-yang HAN Jian-min XU Bin-shi LIU Shi-can ZHOU Zhong-rong . Institute of Materials Science Engineering Beijing Jiaotong University Beijing China . Institute of Surface Engineering Chinese Society of Mechanical Engineering Beijing China . Institute ofTribology Southwest Jiaotong University Chengdu China 《材料热处理学报》2004,25(5)
FRETTING is referring to a reciprocating motion withthe small displacement between two components incontact[1].Fretting wear is superficial materialremoval during the fretting.It severely reduces theperformance,efficiency and service lifetime of thecomponents[2],Thermal spraying has been employedto enhance the fretting wear resistance of components,and the fretting wear behavior of the coatings has beenalso explored.However,the experimental results wereoften contradictive and confusing.On … 相似文献
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《Synthetic Metals》2005,148(2):175-178
Data-storage and memory applications of conjugated polymers and organic semiconductors are generally probed by device current or dielectric properties to determine the storage and switching properties. In this article, we use photoluminescence as an alternate method of probing the states of the devices. We have fabricated such devices based on a polythiophene derivative, and recorded photoluminescence (PL) spectra during and after applying bias. The presence of localized charges on the backbone of the polymer has been found to modulate the PL intensity. Since the relaxation of the space charges is slow, we have shown that PL intensity can be used as a probe for memory applications to read the state of the device. PL as a probe for memory applications of polymeric materials offers an intrinsic advantage that the state can be read without affecting the device properties. 相似文献
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The selection of which requirements should be implemented in the next software release is an important and complex task in the software development process, considering the presence of budget constraints and other conflicting aspects. In this context, search based software engineering, has the main objective of applying automatic search methods to solve complex software engineering problems. However, most of these methods do not consider human expertise during the search, especially due to the difficulty in mathematically modeling the user's preferences. Consequently, the user can present some resistance or place little confidence in the final results, given that his/her knowledge and domain expertise was not properly considered in the solution construction. This paper aims at proposing an interactive model for the next release problem using ant colony optimization, where the user can define which requirements he/she would like to include or not in the next release. Employing humans and a simulator, an empirical study was performed that considers real-world and artificial instances. The achieved results demonstrate that the loss of score was, on average, 12% when it was compared with a solution with no human intervention. On the other hand, the algorithm generates solutions that have more than 80% of the met preferences, as defined by the users. Furthermore, the results showed that ACO can be an interesting choice as an interactive search engine, given the low quantity of interactions that are required to reach good solutions. 相似文献
60.
Hong Lai Mehmet A. Orgun Josef Pieprzyk Jing Li Mingxing Luo Jinghua Xiao Fuyuan Xiao 《Quantum Information Processing》2016,15(11):4663-4679
We propose an approach that achieves high-capacity quantum key distribution using Chebyshev-map values corresponding to Lucas numbers coding. In particular, we encode a key with the Chebyshev-map values corresponding to Lucas numbers and then use k-Chebyshev maps to achieve consecutive and flexible key expansion and apply the pre-shared classical information between Alice and Bob and fountain codes for privacy amplification to solve the security of the exchange of classical information via the classical channel. Consequently, our high-capacity protocol does not have the limitations imposed by orbital angular momentum and down-conversion bandwidths, and it meets the requirements for longer distances and lower error rates simultaneously. 相似文献