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CROSSED PRODUCTS BY FINITE GROUP ACTIONS WITH CERTAIN TRACIAL ROKHLIN PROPERTY 被引量:4
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作者 范庆斋 方小春 《Acta Mathematica Scientia》 SCIE CSCD 2018年第3期829-842,共14页
We introduce a special tracial Rokhlin property for unital C~*-algebras. Let A be a unital tracial rank zero C~*-algebra(or tracial rank no more than one C~*-algebra). Suppose that α : G → Aut(A) is an actio... We introduce a special tracial Rokhlin property for unital C~*-algebras. Let A be a unital tracial rank zero C~*-algebra(or tracial rank no more than one C~*-algebra). Suppose that α : G → Aut(A) is an action of a finite group G on A, which has this special tracial Rokhlin property, and suppose that A is a α-simple C~*-algebra. Then, the crossed product C~*-algebra C~*(G, A, α) has tracia rank zero(or has tracial rank no more than one). In fact,we get a more general results. 展开更多
关键词 C~*-algebras Rokhlin property crossed product C~*-algebra
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Accurate Formulae for the Cross-Section Data for the Radio-Halogen I-123 from Cyclotron Production
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作者 Sherif S. Nafee Amir M. Al-Ramady Manal F. Alshammari 《Open Journal of Applied Sciences》 2023年第9期1489-1497,共9页
123I is the most widely used cyclotron-produced radio-halogen in medical research. In this paper, excitation function formulae for the nuclear reactions of 123I production are introduced. 124Te (p, 2n)123I and 127I (p... 123I is the most widely used cyclotron-produced radio-halogen in medical research. In this paper, excitation function formulae for the nuclear reactions of 123I production are introduced. 124Te (p, 2n)123I and 127I (p, 5n)123Xe → 123I nuclear reactions have been studied as a function of the energy of the neutrons. Both two formulae were created using the least squares regression of the experimental cross sections data, which were obtained from the Experimental Nuclear Reaction Data EXFOR Database version of 2023. The proposed formulae were evaluated using two statistical indicators for goodness-of-fit. High agreement was observed between the empirical and experimental results for both nuclear processes. 展开更多
关键词 cross Section Radioisotope production PET SPECT and Radio-Halogens
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Cotorsion Dimension of Weak Crossed Products
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作者 Chen Hua-xi Liang Jin-rong 《Communications in Mathematical Research》 CSCD 2018年第2期133-140,共8页
Let H be a finite-dimensional weak Hopf algebra over a field κ and A an associative algebra, and A#;H a weak crossed product. In this paper, a spectral sequence for Ext is constructed which yields an estimate for cot... Let H be a finite-dimensional weak Hopf algebra over a field κ and A an associative algebra, and A#;H a weak crossed product. In this paper, a spectral sequence for Ext is constructed which yields an estimate for cotorsion dimension of A#;H in terms of the corresponding data for H and A. 展开更多
关键词 weak crossed product cotorsion dimension projective resolution
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Reversible Properties of Monoid Crossed Products
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作者 Yin Yue Zhao Liang Gu Qin-qin 《Communications in Mathematical Research》 CSCD 2018年第1期36-46,共11页
We study the reversible properties of monoid crossed products. The new class of strongly CM-reversible rings is introduced and characterized. This class of rings is a generalization of those of strongly reversible rin... We study the reversible properties of monoid crossed products. The new class of strongly CM-reversible rings is introduced and characterized. This class of rings is a generalization of those of strongly reversible rings, skew strongly reversible rings and strongly M-reversible rings. Some well-known results on this subject are generalized and extended. 展开更多
关键词 monoid crossed product strongly reversible ring strongly CM-reversible ring
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Homological Dimension of Crossed Products of Hopf Algebras
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作者 王志玺 武艳辉 《Northeastern Mathematical Journal》 CSCD 2004年第4期403-410,共8页
Let H be a finite dimensional cocommutative Hopf algebra and A an H-module algebra. In this paper, we characterize the projectivity (injectivity) of M as a left A#σH-module when it is projective (injective) as a left... Let H be a finite dimensional cocommutative Hopf algebra and A an H-module algebra. In this paper, we characterize the projectivity (injectivity) of M as a left A#σH-module when it is projective (injective) as a left A-module. The sufficient and necessary condition for A#σH, the crossed product, to have finite global homological dimension is given, in terms of the global homological dimension of A and the surjectivity of trace maps, provided that H is cocommutative and A is commutative. 展开更多
关键词 homological dimension weak action crossed product
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Generalized Crossed Pro ducts and L-R Smash Pro ducts of Multiplier Hopf Algebras
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作者 ZHAO Li-hui WANG Cai-hong 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第2期283-291,共9页
In this paper we generalize the notions of crossed products and L-R smash products in the context of multiplier Hopf algebras. We use comodule algebras to define generalized diagonal crossed products, L-R smash produc... In this paper we generalize the notions of crossed products and L-R smash products in the context of multiplier Hopf algebras. We use comodule algebras to define generalized diagonal crossed products, L-R smash products, two-sided smash products and two-sided crossed products and prove that they are all associative algebras. Then we show the isomorphic relations of them. 展开更多
关键词 multiplier Hopf algebra diagonal crossed product L-R smash product twosided smash product two-sided crossed product
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L-R Crossed积的Maschke定理(英文)
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作者 周小燕 李强 《南京大学学报(数学半年刊)》 CAS 2011年第2期139-148,共10页
本文给出了L-R crossed积的Maschke定理,推广了Blattner和Montgomery给出的crossed积的Maschke定理.
关键词 HOPF代数 L-R crossed crossed MASCHKE定理
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Frame-indifference of cross products,rotations,and the permutation tensor 被引量:1
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作者 Maolin Du 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2020年第2期116-119,共4页
Under improper transformations,the traditional transformation laws for cross products,the permutation tensor,and rotations are incorrect.For a cross product,using a counter-example the left-hand rule is proved wrong.T... Under improper transformations,the traditional transformation laws for cross products,the permutation tensor,and rotations are incorrect.For a cross product,using a counter-example the left-hand rule is proved wrong.The unique rule for a cross product is the right-hand rule.Coordinate systems have handedness,while a cross product is frame-indifference.Since the permutation tensor is defined as a triple product including a cross product,the law for the permutation tensor is false.For a rotation,its pseudovector representation is incorrect,because the mirror is an auxiliary device to produce the virtual image rather than a new coordinate system or reference frame. 展开更多
关键词 Pseudovector cross product IMPROPER transformation Handed coefficient PERMUTATION TENSOR
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An improved cross entropy algorithm for steelmaking-continuous casting production scheduling with complicated technological routes 被引量:8
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作者 王桂荣 李歧强 王鲁浩 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第8期2998-3007,共10页
In order to increase productivity and reduce energy consumption of steelmaking-continuous casting(SCC) production process, especially with complicated technological routes, the cross entropy(CE) method was adopted to ... In order to increase productivity and reduce energy consumption of steelmaking-continuous casting(SCC) production process, especially with complicated technological routes, the cross entropy(CE) method was adopted to optimize the SCC production scheduling(SCCPS) problem. Based on the CE method, a matrix encoding scheme was proposed and a backward decoding method was used to generate a reasonable schedule. To describe the distribution of the solution space, a probability distribution model was built and used to generate individuals. In addition, the probability updating mechanism of the probability distribution model was proposed which helps to find the optimal individual gradually. Because of the poor stability and premature convergence of the standard cross entropy(SCE) algorithm, the improved cross entropy(ICE) algorithm was proposed with the following improvements: individual generation mechanism combined with heuristic rules, retention mechanism of the optimal individual, local search mechanism and dynamic parameters of the algorithm. Simulation experiments validate that the CE method is effective in solving the SCCPS problem with complicated technological routes and the ICE algorithm proposed has superior performance to the SCE algorithm and the genetic algorithm(GA). 展开更多
关键词 遗传算法 生产调度 炼钢连铸 工艺路线 交叉熵 概率分布模型 最优个体 连铸生产过程
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Model-based cross section calculations on production of 43,34Sc,45Ti, 51Cr, 54Mn, and 55Fe radioisotopes
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作者 Mustafa Yigit 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第4期128-136,共9页
A cross section database on excitation functions of reactions produced by charged particles is essential for many areas of nuclear research. Particularly, accurate knowledge on nuclear cross sections for the cyclotron... A cross section database on excitation functions of reactions produced by charged particles is essential for many areas of nuclear research. Particularly, accurate knowledge on nuclear cross sections for the cyclotron production of radioisotopes is very important for nuclear medicine. In the present paper, the cross section calculations for the production of^(43),^(34)Sc,^(45)Ti,^(51)Cr,^(54)Mn, and^(55) Fe radioisotopes were carried out by the use of ALICE/ASH code using the Fermi gas model, Kataria Ramamurthy Fermi gas model, and superfluid nuclear model for nuclear level density. Thereby, these model calculations were compared with the available measured data. 展开更多
关键词 RADIOISOTOPE productION Scandium-44 Chromium-51 SUPERFLUID nuclear model cross section
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Time dependence of entropy flux and entropy production for a dynamical system driven by noises with coloured cross-correlation 被引量:2
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作者 谢文贤 徐伟 蔡力 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第1期42-46,共5页
This paper shows the Fokker-Planck equation of a dynamical system driven by coloured cross-correlated white noises in the absence and presence of a small external force. Based on the Fokker-Planck equation and the def... This paper shows the Fokker-Planck equation of a dynamical system driven by coloured cross-correlated white noises in the absence and presence of a small external force. Based on the Fokker-Planck equation and the definition of Shannon's information entropy, the time dependence of entropy flux and entropy production can be calculated. The present results can be used to explain the extremal behaviour of time dependence of entropy flux and entropy production in view of the dissipative parameter γ of the system, coloured cross-correlation time τ and coloured cross-correlation strength λ. 展开更多
关键词 information entropy entropy flux entropy production coloured cross-correlation Fokker-Planck equation
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Improved Cross Entropy Algorithm for Steelmaking Continuous Casting Production Scheduling with Minimum Power Consumption
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作者 王桂荣 李歧强 杨凡 《Journal of Donghua University(English Edition)》 EI CAS 2015年第1期23-29,共7页
A matrix encoding scheme for the steelmaking continuous casting( SCC) production scheduling( SCCPS) problem and the corresponding decoding method are proposed. Based on it,a cross entropy( CE) method is adopted and an... A matrix encoding scheme for the steelmaking continuous casting( SCC) production scheduling( SCCPS) problem and the corresponding decoding method are proposed. Based on it,a cross entropy( CE) method is adopted and an improved cross entropy( ICE) algorithm is proposed to solve the SCCPS problem to minimize total power consumption. To describe the distribution of the solution space of the CE method,a probability model is built and used to generate individuals by sampling and a probability updating mechanism is introduced to trace the promising samples. For the ICE algorithm,some samples are generated by the heuristic rules for the shortest makespan due to the relation between the makespan and the total power consumption,which can reduce the search space greatly. The optimal sample in each iteration is retained through a retention mechanism to ensure that the historical optimal sample is not lost so as to improve the efficiency and global convergence. A local search procedure is carried out on a part of better samples so as to improve the local exploitation capability of the ICE algorithm and get a better result. The parameter setting is investigated by the Taguchi method of design-of-experiment. A number of simulation experiments are implemented to validate the effectiveness of the ICE algorithm in solving the SCCPS problem and also the superiority of the ICE algorithm is verified through the comparison with the standard cross entropy( SCE) algorithm. 展开更多
关键词 steelmaking continuous casting(SCC) production scheduling power consumption cross entropy(CE) PROBABILITY
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Calculation of production cross sections of γ-rays from thermal-neutron captures
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作者 ZHOUChun-Mei WUZhen-Dong 《Nuclear Science and Techniques》 SCIE CAS CSCD 2004年第6期328-334,共7页
The calculation methods of production cross sections of γ-rays for thermal-neutron captures are briefly presented. The check of intensity balance is made. The examples are given to illustrate its application.
关键词 中子反应 γ-射线 热中子俘获 数据计算 乘积横截面
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Hopf代数与Crossed积
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作者 宋传宁 《上海师范大学学报(自然科学版)》 1994年第4期16-20,共5页
本文主要进一步讨论了Hopf代数H与H-模代数B的Crossed积,并且得出一个有用的结论.当时,这里是代数同构,有.
关键词 HOPF代数 H-模代数 作用 弱作用 crossed
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M_(αβ) X-ray production cross sections of Pb and B iby 9–40 keV electron impact
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作者 吴英 王冠鹰 +1 位作者 穆强 赵强 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第1期206-210,共5页
The experimental data of Mαβ X-ray production cross sections for Pb and Bi by 9–40 keV electron impact have been given. Thin films with thick carbon substrates are used in the experiment. The effects of target stru... The experimental data of Mαβ X-ray production cross sections for Pb and Bi by 9–40 keV electron impact have been given. Thin films with thick carbon substrates are used in the experiment. The effects of target structure on the Mαβ X-ray production cross sections are corrected by using the Monte Carlo method. The corrected experimental data are compared with calculated cross sections in terms of the distorted-wave Born approximation(DWBA) theory. The measured Mαβ X-ray production cross sections for Pb and Bi are lower than the DWBA calculations. The atomic relaxation parameters used in comparing the DWBA values with experimental results affect the degree of difference. 展开更多
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药物临床研究阶段申办者和生产场地变更研究六:临床研究阶段申办者和生产场地跨境变更的风险分析 被引量:1
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作者 陈震 王方敏 +4 位作者 吴正宇 于冰 陈江鹏 高丽萍 杨建红 《中国药事》 CAS 2024年第5期538-548,共11页
目的:通过对临床研究阶段申办者、生产场地发生跨境变更时的风险变化进行分析,为申办者和生产场地的跨境变更管理提供参考。方法:基于申办者和生产场地不同组合情形的初始风险评价结果和采取风险管控措施后的风险再评价结果,比较分析不... 目的:通过对临床研究阶段申办者、生产场地发生跨境变更时的风险变化进行分析,为申办者和生产场地的跨境变更管理提供参考。方法:基于申办者和生产场地不同组合情形的初始风险评价结果和采取风险管控措施后的风险再评价结果,比较分析不同组合情形之间发生变更时变更前后的“风险指数水平”变化。结果与结论:基于初始风险评价结果,有两种变更情形的风险指数水平在变更后较变更前降低;基于风险再评价结果,有四种变更情形的风险指数水平在变更后较变更前降低。 展开更多
关键词 临床研究阶段 申办者 生产场地 跨境变更 风险分析
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基于产教融合的跨境电子商务专业校企协同育人模式研究 被引量:3
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作者 何伟 何思瑶 《物流科技》 2024年第5期175-178,共4页
随着经济全球化的发展,跨境电子商务已经成为了国际贸易的重要形式,为推动国际贸易和经济发展提供了新的机遇和挑战。跨境电子商务的发展对人才的需求越来越高,如何培养高素质的跨境电子商务人才已经成为了当前教育领域的一个热点问题... 随着经济全球化的发展,跨境电子商务已经成为了国际贸易的重要形式,为推动国际贸易和经济发展提供了新的机遇和挑战。跨境电子商务的发展对人才的需求越来越高,如何培养高素质的跨境电子商务人才已经成为了当前教育领域的一个热点问题。文章从产教融合的角度出发,结合校企协同育人的模式,对跨境电子商务专业人才培养模式进行了探讨和研究。通过分析当前跨境电子商务市场的现状和发展趋势,总结了跨境电子商务人才的基本要求和能力素质,从而提出了基于产教融合的校企协同育人模式。在模式实施中,需要建立稳定的校企合作关系,建设完善的实践基地,实现课程的有效对接,并注重实践教学的重要性。通过研究,旨在为跨境电子商务专业人才的培养提供参考,为推动产教融合的校企协同育人模式提供借鉴。 展开更多
关键词 跨境电子商务 人才培养 产教融合 校企协同育人
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基于向量叉乘标签分配的遥感图像目标检测算法
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作者 禹鑫燚 林密 +1 位作者 卢江平 欧林林 《高技术通讯》 CAS 北大核心 2024年第2期132-142,共11页
近年来遥感图像目标检测受到了广泛的关注,主流的遥感图像目标检测器通过预设锚框与真实框之间的交并比(IoU)进行正负样本的划分。为了解决基于IoU的标签分配方法在遥感图像小而密集目标中存在复检和漏检的问题,本文提出了一种基于向量... 近年来遥感图像目标检测受到了广泛的关注,主流的遥感图像目标检测器通过预设锚框与真实框之间的交并比(IoU)进行正负样本的划分。为了解决基于IoU的标签分配方法在遥感图像小而密集目标中存在复检和漏检的问题,本文提出了一种基于向量叉乘标签分配的遥感图像目标检测算法YOLOXR。首先,提出了一种标签粗分配策略,通过向量叉乘的方法判断特征图的像素点是否在旋转目标内或者目标中心点附近的旋转正方形框内,从而确定其是否为候选正样本。其次,为了降低边缘低质量候选正样本对标签分配的影响,提出了旋转中心度量方法,通过向量叉乘判断像素点距离中心点的远近程度进而赋予不同的权重。最后,基于最优传输的方法(sim OTA)选取真实框和样本点的最优匹配对,使得总体代价最小,进而为旋转目标分配合适的标签。此外,为了解决旋转IoU损失不可导以及Smooth L1损失难以权衡旋转框各个参数的问题,通过计算真实框和预测框二维高斯分布的Kullback-Leibler散度(KLD)来替代IoU。在公开的遥感图像目标检测数据DOTA、HRSC 2016和UCAS-AOD上的大量实验表明,所提方法优于目前绝大多数旋转目标检测算法。 展开更多
关键词 遥感图像 目标检测 标签分配 向量叉乘
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职业教育跨境推广与国际产能合作耦合系统架构
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作者 李富 李卓然 王湘蓉 《宁波职业技术学院学报》 2024年第4期16-23,共8页
职业教育跨境推广与国际产能合作需加强耦合。职业教育跨境推广呈现出校企合作境外办学形式和办学品牌多样化、校企合作人才推广渠道趋于丰富、校企合作专业标准和专业课程推广数量增多等特点。但同时国际产能合作视域下职业教育跨境推... 职业教育跨境推广与国际产能合作需加强耦合。职业教育跨境推广呈现出校企合作境外办学形式和办学品牌多样化、校企合作人才推广渠道趋于丰富、校企合作专业标准和专业课程推广数量增多等特点。但同时国际产能合作视域下职业教育跨境推广还存在一些问题,如国际化技能竞赛与国际产能合作衔接桥梁需要架构、科学研究服务国际产能合作能力有待提升、数字化服务国际产能合作领域亟待加强等。基于现实性、前瞻性和数字化等需求,需要架构职业教育跨境推广与国际产能合作耦合系统,并从激励机制、国际融入、智库建设、行业标准平台搭建、数字化引领、风险防范等维度,构建耦合系统实施的保障机制,推进职业教育服务国际产能合作效能的稳步提升。 展开更多
关键词 职业教育 跨境推广 国际产能合作 耦合
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学科交叉背景下2023年产品设计研究进展及反思
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作者 吕杰锋 孙荦 陆江艳 《创意与设计》 2024年第1期12-18,共7页
为进一步推动产品设计研究向着更深、更广的跨领域融合方向发展,通过文献研究法、Cite Space关键词共现分析及可视化呈现,系统梳理和深度剖析2023年度涵盖国家政策导向、教育体系改革、学术期刊论文发表概况、学位论文热点主题、国家级... 为进一步推动产品设计研究向着更深、更广的跨领域融合方向发展,通过文献研究法、Cite Space关键词共现分析及可视化呈现,系统梳理和深度剖析2023年度涵盖国家政策导向、教育体系改革、学术期刊论文发表概况、学位论文热点主题、国家级基金获批项目、高校与学术机构的论坛会议等多维度资料,揭示产品设计研究领域在学科交叉背景下的发展现状和特点,总结当前产品设计研究在跨学科交融过程中所面临的问题,展望了产品设计研究面向未来社会发展与产业需求、立足本土文化、跨领域创新理论与实践成果的高度融合等核心趋势,对未来研究方向做出了前瞻性的预测与建议。 展开更多
关键词 设计学 产品设计 学科交叉 跨领域融合
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