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101.
Bai  Qingchun  Wei  Kai  Zhou  Jie  Xiong  Chao  Wu  Yuanbin  Lin  Xin  He  Liang 《The Journal of supercomputing》2021,77(9):9474-9493
The Journal of Supercomputing - Sentiment analysis in Danmaku video interaction aims at measuring public mood in respect of the video, which is helpful for the potential applications in behavioral...  相似文献   
102.
Gu  Min  Gu  Yanhui  Luo  Weilan  Xu  Guandong  Yang  Zhenglu  Zhou  Junsheng  Qu  Weiguang 《Neural computing & applications》2021,33(11):6009-6025
Neural Computing and Applications - Semantic understanding is an essential research issue for many applications, such as social network analysis, collective intelligence and content computing,...  相似文献   
103.
Wang  Yunduo  Li  Tong  Zhou  Qixiang  Du  Jinlian 《Requirements Engineering》2021,26(3):301-323
Requirements Engineering - Bridging the gap between academia and industry is an important issue to promote the practicality of i* framework. Researchers have been dealing with this issue from...  相似文献   
104.
Lu  Qiang  Tao  Fan  Zhou  Shuo  Wang  Zhiguang 《Neural computing & applications》2021,33(14):8495-8511
Neural Computing and Applications - Most traditional genetic programming methods that handle symbolic regression are random algorithms without memory and direction. They repeatedly search for the...  相似文献   
105.
Continuum-type optimality criteria for the iterative optimization of large finite element systems (i.e. systems with over ten thousand finite elements) are discussed. By investigating optimization problems with up to one million elements and one million variables, it is shown that for a single displacement constraint the proposed method results in a rapid and almost uniform convergence, the rate of which, even for relatively ill-conditioned problems, does not depend significantly on the number of elements. Additional refinements, including upper and lower limits on the cross-sectional dimensions, segmentation, allowance for selfweight and the cost of supports, non-linear and non-separable objective functions, inclusion of shear deformations, built-up cross-sections as well as additional stress constraints and two-dimensional (plane stress) problems, will be considered in Part II of this contribution. The current development constitutes an extension and generalization of pioneering work by Berke, Khot, Venkayya and their associates, whose methods are also reviewed herein. In addition to an elementary truss example and a more advanced beam example, some simple layout optimization problems are considered in this Part. A special feature of the paper is that all numerical results presented are confirmed by closed form analytical solutions.  相似文献   
106.
Equations of state and contact values of hard-sphere radial distribution functions (rdf's) which are given by a linear combination of the Percus— Yevick and scaled-particle virial expressions are considered. In the one-component case the mixing coefficient() is, in general, a function of the volume fraction. In mixtures the coefficient( i ,d i ), in general, depends upon the volume fraction i , and diameterd i , of each species,i andj. For the contact valuesY ij of the rdf's, the mixing coefficients ij ( k ) also depend on speciesi andj. Density expansions for the exact for the one-component hard-sphere fluid are obtained and compared with several approximations made in earlier works and in our own work, as well as with simulations. For a mixture, it turns out that one cannot obtain the exact fourth virial coefficient by using a linear combination of the Percus-Yevick and scaled-particle virial expressions forY ij unless one allows ij to depend on mole fractionsx i even at the zeroth order of its density expansion. We also find that ij must depend on particle speciesi andj in order to satisfy the exact limits obtained earlier by Sung and Stell. A new equation of state for the binary hard-sphere mixture which satisfies all the exact limits we have considered is suggested.Paper presented at the Tenth Symposium on Thermophysical Properties, June 20–23, 1988, Gaithersburg, Maryland, U.S.A.  相似文献   
107.
本文研制了一台测量电子束和β射线吸收剂量的外推电离室,其空腔室壁材料可拆换并分别与空气、组织和硅等效,收集电极名义直径为1.5、3、10和30mm,空气空腔可变范围为0.2~15mm。该外推电离室具有在空腔内部测温,自动改变窗口上方材料厚度及采用微型计算机控制等特点。适用于测10 MeV能量以下,剂量率为10~5~10~(-3)Gy/h的电子或β射线吸收剂量。整个外推电离室自动测剂量系统在测~(204)TLβ放射源表面剂量率的不确定度为2.3%。测1.5 MeV电子束在硅和哈密瓜深部剂量率时,不确定度分别为4.0%和2.8%。  相似文献   
108.
Gu  Q.  Liu  W. F.  Wong-Ng  Winnie  Wu  X. X.  Wang  C.  Zhou  W.  Wang  S. Y. 《Journal of Electroceramics》2021,47(2):42-50

Layered perovskite Ca2.91Na0.09Ti2-xRhxO7 (x?=?0.00, 0.02, 0.04, 0.06) were synthesized by a conventional solid-state reaction. Room temperature ferroelectricity has been confirmed. The remanent polarization increases with an increase of Rh content, which is due to a larger oxygen octahedral distortion by Rh doping. The coercive field increases with Rh doping as the pinning effect of oxygen vacancies reduce the mobility of domain wall. Remanent polarization and coercive field are caused by different mechanisms, so it is possible to modulate them independently to meet the requirement of application in ferroelectric field. The concentration of oxygen vacancy increased with Rh doping, leading to the significant increase of leakage current density. The bandgap of samples doped with Rh drastically decrease and the visible light response of the sample was improved by Rh doping due to the formation of impurity energy levels within the band gap.

  相似文献   
109.
董仕节  Y.Zhou 《热加工工艺》2002,(6):21-23,26
研究了电极表面处理和电极材料对镀镍钢板和镍板微型点焊时电极粘附的影响。结果表明:电极表面涂敷TiC后能提高CuCrZr电极和GlidCop60电极的抗粘附性能,其原因是涂层中的TiC能阻碍电极和镀镍板之间的局部焊接;GlidCop60电极的抗粘附性能优于CuCrZr电极的抗粘附性能,其原因是弥散分布于GlidCop60电极中的Al2O3能阻碍电极和镀镍板之间的局部焊接。  相似文献   
110.
塑料在包装领域有着广泛的应用,其中聚酯(PET)性能优良,应用领域不断扩大。介绍了塑料包装不断通现的新技术,以及塑料包装环保问题的几点思路。  相似文献   
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