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Chinese Chemical Letters 2021年第2期32卷 713-716页

作者： Xiai Luo Wenguang Li Haiyan Lu Guobo deng Yuan Yang chunming Yang Yun Liang National&Local Joint Engineering Laboratory for New Petro-chemical Materials and Fine Utilization of Resources Key Laboratory of Chemical Biology and Traditional Chinese Medicine ResearchMinistry of EducationKey Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan ProvinceCollege of Chemistry and Chemical EngineeringHunan Normal UniversityChangsha 410081China Hunan University of Medicine Huaihua 418000China

A simultaneous C2-H arylation and C8-H alkylation of naphthalene ring has been achieved by palladiumcatalyzed cascade reaction of N-(2-halophenyl)-2-(naphthalen-1-yl)acrylamides with aryl iodides,which provides an efficient method for synthesizing various aryl-substituted spirocyclic *** protocol enables three C-C bonds formation via an intramolecular Heck reaction and sequentially regioselective C-H bond activation.

关键词： Palladium-catalyzed Cascade reaction Regioselective C-H activation Naphthalene ring Spirocyclic oxindoles

SEVERAL CRYPTOGRAPHIC APPLICATIONS OF ∑-PROTOCOL

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Journal of Systems Science & Complexity 2009年第2期22卷 260-279页

作者： chunming TANG Zheng-an YAO School of Mathematics and Information Science Guangzhou University Guangzhou 510006 China State KeyLaboratory of Information Security Institute of Software Science Beijing 100190~ China. School of Mathematics and Computational Sciences Sun Yat-Sen University Guangzhou 510275 China.

∑-protocol has been proved to be a very powerful cryptographic tool and widely used in nnmerous important cryptographic applications. In this paper, the authors make use of ∑-protocol as a main tool to resolve the following difficult problems 1-3 and to construct three ettlcient cryptographic protocols 4 6：1） How to construct a protocol for proving a secret integer to be a Blum integer with form PQ, where P, Q are two different primes and both -- 3（mod 4）;2） How to construct a protocol for proving a secret polynomial with exact degree t - 1 iil a （t, n）- threshold secret sharing scheme：3） How to construct witness indistinguishable and witness hiding protocol not from zero-knowledge proof;4） A publicly verifiable secret sharing scheme with information-theoretic security;5） A delegateable signature scheme under the existence of one-way permutations;6） Non-interactive universal designated verifier signature schemes.

关键词： ∑-protocol Blum integer delegateable signature secret sharing witness hiding protocol,witness indistinguishable protocol universal designated verifier signature.

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添加剂对钢渣微晶玻璃微晶化行为的影响

陶瓷 2003年第1期 20-23页

作者：邓春明肖汉宁赵运才长沙矿冶研究院 410012 湖南大学材料科学与工程学院长沙410082

研究了还原剂、氧化剂及ZrO2 对钢渣微晶玻璃的微晶化行为和显微结构的影响。实验结果表明 ,在一定的还原剂作用下 ,钢渣玻璃中形成的Fe3O4 有利于促进玻璃的核化和晶化。在氧化剂作用下 ,钢渣玻璃中形成均匀、大小约为 2μm的晶粒。Zr... 详细信息

研究了还原剂、氧化剂及ZrO2 对钢渣微晶玻璃的微晶化行为和显微结构的影响。实验结果表明 ,在一定的还原剂作用下 ,钢渣玻璃中形成的Fe3O4 有利于促进玻璃的核化和晶化。在氧化剂作用下 ,钢渣玻璃中形成均匀、大小约为 2μm的晶粒。ZrO2 可以提高玻璃熔体的粘度并使晶粒细化 ,形成 1～ 2 μm的晶粒 ,而未添加ZrO2 的晶粒超过 10 μm。

关键词：添加剂钢渣微晶玻璃微晶化行为影响钢铁废渣

Scheduling Reconfigurable Service Function Chain

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Chinese Journal of Electronics 2019年第6期28卷 1244-1249页

作者： ZHU Kai WU chunming ZHOU Boyang College of Computer Science Zhejiang University Zhejiang Lab

Network function virtualization(NFV),has been widely adopted in existing networks since it brings lower capital expenditure and operating expense,as well as flexible and elastic deployment. Based on NFV, dynamic Service function chain(SFC) provides more comprehensive and thorough traffic steering over a series of middleboxes, e.g., DPI, and IDS. Nevertheless, dynamic SFC involves internal state migration in middleboxes, making it hard to allocate SFC *** propose a reconfigurable SFC scheduling approach with consideration on resource constraints and race of the state migration to collaborate the execution of the SFC reconfiguration, in the reasonable fashion based on a heuristic algorithm. The evaluation is conducted through discrete event simulation to validate the efficiency of our reconfigurable SFC scheduling, and the results demonstrate that the proposed method outperforms First Come First Serve scheduling and random scheduling.

关键词： Network function virtualization(NFV) Service function chain(SFC) State migration SDN

Two-Order Approximate and Large Stepsize Numerical Direction Based on the Quadratic Hypothesis and Fitting Method

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IEEE/CAA Journal of Automatica Sinica 2020年第3期7卷 901-909页

作者： Xiaoli Yin chunming Li Yuan Zhang School of Mechanical and Electrical Engineering China University of Petroleum(East China)Qingdao 266580 Shengli College in China University of Petroleum(East China) Dongying 257061China School of Pipeline and Civil Engineering China University of Petroleum(East China)Qingdao 266580

Many effective optimization algorithms require partial derivatives of objective functions, while some optimization problems' objective functions have no derivatives. According to former research studies, some search directions are obtained using the quadratic hypothesis of objective functions. Based on derivatives, quadratic function assumptions, and directional derivatives, the computational formulas of numerical first-order partial derivatives, second-order partial derivatives, and numerical second-order mixed partial derivatives were constructed. Based on the coordinate transformation relation, a set of orthogonal vectors in the fixed coordinate system was established according to the optimization direction. A numerical algorithm was proposed, taking the second order approximation direction as an example. A large stepsize numerical algorithm based on coordinate transformation was proposed. Several algorithms were validated by an unconstrained optimization of the two-dimensional Rosenbrock objective function. The numerical second order approximation direction with the numerical mixed partial derivatives showed good results. Its calculated amount is 0.2843% of that of without second-order mixed partial derivative. In the process of rotating the local coordinate system 360°, because the objective function is more complex than the quadratic function, if the numerical direction derivative is used instead of the analytic partial derivative, the optimization direction varies with a range of 103.05°. Because theoretical error is in the numerical negative gradient direction, the calculation with the coordinate transformation is 94.71% less than the calculation without coordinate transformation. If there is no theoretical error in the numerical negative gradient direction or in the large-stepsize numerical optimization algorithm based on the coordinate transformation, the sawtooth phenomenon occurs. When each numerical mixed partial derivative takes more than one point, th

关键词： Directional derivative numerical differential optimization method quadratic function hypothesis

A comparison of the distributions of carbazoles and dibenzothiophenes in western Qaidam Basin, Northwest China

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Chinese Journal Of Geochemistry 2014年第2期33卷 194-200页

作者： GUAN Mingming ZHANG chunming Key Laboratory of Exploration Technologies for Oil and Gas Resources (Yangtze University) Ministry of Education School of Earth Environment and Water Resources Yangtze University College of Technology & Engineering Yangtze University

Variations in the distributions of carbazoles and dibenzothiophenes were investigated in a set of source rocks, which differ mainly in their maturity levels during immature-mature stages. A comparison of the distributions of carbazoles and dibenzothiophenes has revealed the main results as follows: variations in the relative amounts ①of C0-, C1-, C2-dibenzothiophenes show a low correlation with that of the corresponding carbazoles, with the former's being much higher than the latter's; variations in the relative amounts of methyldibe② nzothiophene isomers also display a low correlation with that of the corresponding methylcarbazoles, with 4-/4- +1-methyldibenzothiophene ratio ranging from 0.52 to 0.96, while the corresponding carbazole ratio of 1-/1- +4-methylcarbazole only being 0.71±0.05; the mat③ urity parameter for 4,6-/4,6- +1,4-dimethyldibenzothiohene, ranging from 0.34 to 0.75, shows a remarkable linear correlation with the corresponding ratio of 1,8-/1,8- +1,4-dimethylcarbazole(R2>0.84). The un-correlation may indicate some different geological-geochemical fates for some isomers of dibenzothiophenes and carbazoles. The high correlation may reveal a strong maturation dependence on the dimethylcarbazole distributions, indicating that attention should be paid when 1,8-/1,8- +1,4-dimethylcarbazole is used as a petroleum migration indicator.

关键词：二苯并噻吩中国西北地区柴达木盆地咔唑西部地区成熟度参数比值范围线性相关性

Fault Diagnosis Method of Rolling Bearing Based on MSCNN-LSTM

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Computers, Materials & Continua 2024年第6期79卷 4395-4411页

作者： chunming Wu Shupeng Zheng Key Laboratory of Modern Power System Simulation and Control&Renewable Energy Technology Ministry of EducationNortheast Electric Power UniversityJilin132012China Ministry of Education Northeast Electric Power UniversityJilin132012China

Deep neural networks have been widely applied to bearing fault diagnosis systems and achieved impressive success *** address the problem that the insufficient fault feature extraction ability of traditional fault diagnosis methods results in poor diagnosis effect under variable load and noise interference scenarios,a rolling bearing fault diagnosis model combining Multi-Scale Convolutional Neural Network(MSCNN)and Long Short-Term Memory(LSTM)fused with attention mechanism is *** adaptively extract the essential spatial feature information of various sizes,the model creates a multi-scale feature extraction module using the convolutional neural network(CNN)learning *** learning capacity of LSTM for time information sequence is then used to extract the vibration signal’s temporal feature *** parallel large and small convolutional kernels teach the system spatial local *** gathers temporal global features to thoroughly and painstakingly mine the vibration signal’s characteristics,thus enhancing model ***,bearing fault diagnosis is accomplished by using the SoftMax *** experiment outcomes demonstrate that the model can derive fault properties entirely from the initial vibration *** can retain good diagnostic accuracy under variable load and noise interference and has strong generalization compared to other fault diagnosis models.

关键词： Bearing fault diagnosis convolutional neural network short-long-term memory network feature fusion

Monotone Span Program vs. Linear Code

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Chinese Journal of Electronics 2016年第6期25卷 991-998页

作者： TANG chunming CHEN Yuenai GAO Xuhong School of Mathematics and Information Sciences Guangzhou University Key Laboratory of Mathematics and Interdisciplinary Sciences of Guangdong Higher Education Institutes Guangzhou University Department of Mathematical Sciences Clemson University

Monotone span program(MSP) and Linear code(LC) are efficient tools to construct Linear secret sharing scheme(LSSS) for a given access structure. Since the size of an MSP or the length of an LC corresponds to the communicational complexity of an LSSS, one main motivation to study MSPs or LCs is the lower bound for their sizes or lengths. Therefore, it is one of the most important open problems how to efficiently construct an MSP or LC for a given access structure Γ with the smallest sizes or shortest length. Our contributions are: We extend TANG et al.’s result, showing that, for any given access structureΓ, there exists an MSP or an LC to realize Γ if and only if a system of quadratic equations has solutions; We utilize the relationship between LCs and MSPs to obtain the greatest lower bound on the row size and the column size of MSPs realizing a given Γ, as well as an upper bound on the column size of MSPs; We give an algorithm to construct an MSP with the smallest sizes.

关键词： Cryptography Secret sharing scheme Monotone span program Linear code Size

Apolipoprotein E Drives Early Blood–Brain Barrier Damage in Alzheimer’s Disease

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Neuroscience Bulletin 2021年第2期37卷 281-283页

作者： Qianqian Zhang chunming Xie Department of Neurology Affiliated ZhongDa HospitalSchool of MedicineSoutheast UniversityNanjing 210009China Neuropsychiatric Institute Affiliated Southeast UniversityNanjing 210009China

Recently,the essential functions of the blood-brain barrier(BBB)have attracted increasing attention in the pathophysiology of Alzheimer's disease(AD)[1].How apolipoprotein E(APOE4),the most important high-risk gene fo... 详细信息

关键词： Blood Alzheimer damage

THE OPTIMAL LINEAR SECRET SHARING SCHEME FOR ANY GIVEN ACCESS STRUCTURE

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Journal of Systems Science & Complexity 2013年第4期26卷 634-649页

作者： TANG chunming GAO Shuhong ZHANG Chengli School of Mathematics and Information Science Guangzhou University Key Laboratory of Mathematics and Interdisciplinary Sciences of Guangdong Higher Education Institutes Guangzhou University Department of Mathematical Sciences Clemson University29634U.S.A

Any linear code can be used to construct a linear secret sharing *** this paper,it is shown how to decide optimal linear codes(i.e.,with the biggest information rate)realizing a given access structure over finite *** amounts to solving a system of quadratic equations constructed from the given access structure and the corresponding adversary *** system becomes a linear system for binary *** algorithm is also given for finding the adversary structure for any given access structure.

关键词： Access structure adversary structure cryptography linear code secret sharing.