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Organic Chemistry Frontiers 2022年第2期9卷 428-435页

作者： Arben Berisa Danijel Glavac Chao Zheng Shu-Li You Matija Gredicak Division of Organic Chemistry and Biochemistry Ruder Boskovic InstituteBijenicka c.5410000 ZagrebCroatia State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of Sciences345 Lingling LuShanghai 200032China

An efficient enantioselective formal Betti reaction between phenols and diaryl ketimines generated in situ from isoindolinone alcohols is described.In a reaction catalyzed by a chiral phosphoric acid,a broad range of ketimines and phenols afforded isoindolinone derivatives comprising a congested quaternary stereogenic center bearing three aryl groups in high yields,and high regioselectivities and enantioselectivities.

关键词： quaternary formal stereo

Polychronous automata and their use for formal validation of AADL models

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Frontiers of Computer Science 2019年第4期13卷 677-697页

作者： Thierry GAUTIER Clement GUY Alexandre HONORAT Paul LE GUERNIC Jean-Pierre TALPIN Loic BESNARD Univ. Rennes Inria Rennes-Bretagne-Atlantique Research Centre F-35000 Rennes France Univ. Rennes CNRS IRISA F-35000 Rennes France

This paper investigates how state diagrams can be best represented in the polychronous model of computation (MoC) and proposes to use this model for code validation of behavior specifications in architecture analysis & design language (AADL). In this relational MoC, the basic objects are signals, which are related through dataflow equations. Signals are associated with logical clocks, which provide the capability to describe systems in which components obey multiple clock rates. We propose a model of finite-state automata, called polychronous automata, which is based on clock relationships. A specificity of this model is that an automaton is submitted to clock constraints, which allows one to specify a wide range of control-related configurations, being either reactive or restrictive with respect to their control environment. A semantic model is defined for these polychronous automata, which relies on boolean algebra of clocks. Based on a previously defined modeling method for AADL software architectures using the polychronous MoC, the proposed model is used as a formal model for the AADL behavior annex. This is illustrated with a case study involving an adaptive cruise control system.

关键词： architecture modeling formal semantics finitestate automaton polychronous model synchronous concurrency code generation AADL

Recent advances on formal methods for safety and security of cyber-physical systems

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Control Theory and Technology 2020年第4期18卷 459-461页

作者： Xiang Yin Shaoyuan Li Department of Automation Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of System Control and Information Processing Ministry of EducationShanghai 200240China

Cyber-physical systems(CPSs)are engineering systems with both computational and physical components[1].Typical CPSs include energy systems,transporation systems,autonomous vchicles,ctc.CPSs are usual hybrid involving complex interactions of continuous dynamics with discrete logics.The development of cotroller design and verification algorithms for such complex systems are crucial and challenging tasks.Everincreasing demands for safety and security of CPSs put stringent constraints on their analysis and design,and ncessitat the use of formal model-based approaches.In recent years,we have witnessed a substantial increase in the use of formal techniques for the verifcation and design of safetyritical and security senstve CPSs[2].

关键词： formal CPS autonomous

Neighbourhood systems based attribute reduction in formal decision contexts

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CAAI Transactions on Intelligence Technology 2019年第4期4卷 245-254页

作者： Xiaohe Zhang Jusheng Mi Meizheng Li Meishe Liang College of Mathematics and Information Science Hebei Normal UniversityShijiazhuangPeople’s Republic of China College of Computer and Cyber Security Hebei Normal UniversityShijiazhuangPeople’s Republic of China Shijiazhuang Vocational Technology Institute ShijiazhuangPeople’s Republic of China

Attribute reduction of formal decision context mainly uses the relationship between two concept lattices generated by the condition and decision attributes to remove redundant condition attributes.By using decision attributes to observe the covering of objects,this study defines two types of consistent sets and reducts in a consistent formal decision context based on neighbourhood systems.Four types of reductions in inconsistent formal decision contexts are also studied.The methods to calculate all types of reductions are formulated by discernibility matrix.Finally,an approach to obtain the decision rules in consistent formal decision context is proposed.

关键词： formal decision context

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保序模块的formal fpv验证

电子技术应用 2022年第8期48卷 38-41,45页

作者：赵亚雪植玉梁其锋石义军深圳市中兴微电子技术有限公司广东深圳518054

与simulation验证相比,formal验证方法可以在短时间内遍历所有可能的激励,大大提高验证的效率。保序模块与时序控制以及流水线控制密切相关,设计规模较大,逻辑复杂度较高。介绍了使用formal fpv验证保序模块的流程,并对JasperGold debu... 详细信息

与simulation验证相比,formal验证方法可以在短时间内遍历所有可能的激励,大大提高验证的效率。保序模块与时序控制以及流水线控制密切相关,设计规模较大,逻辑复杂度较高。介绍了使用formal fpv验证保序模块的流程,并对JasperGold debug结果进行了分析,采用formal fpv验证能提高验证效率,加快验证收敛速度。

关键词： formal fpv 保序模块 JasperGold

基于形式演算和不变式验证的可信算法程序构造(英文)

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China Communications 2011年第4期8卷 58-64页

作者：郑宇军石海鹤薛锦云陈胜勇 College of Computer Science & Technology Zhejiang University of Technology Provincial Lab of High-Performance Computing Technology Jiangxi Normal University

The paper presents a formal and practical approach to dependable algorithm development.First,starting from a formal specification based on the Eindhoven quantifier notation,a problem is regularly reduced to subproblems with less complexity by using a concise set of calculation rules,the result of which establishes a recurrence-based algorithm.Second,a loop invariant is derived from the problem specification and recurrence,which certifies the transformation from the recurrence-based algorithm to one or more iterative programs.We demonstrate that our approach covers a number of classical algorithm design tactics,develops algorithmic programs together with their proof of correctness,and thus contributes fundamentally to the dependability of computer software.

关键词： formal methods algorithm calculation loop invariants program validation

formal Verification of Robertson-Type Uncertainty Relation

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Journal of Quantum Information Science 2015年第2期5卷 58-70页

作者： Takaaki Masuhara Toru Kuriyama Masakazu Yoshida Jun Cheng Department of Intelligent Information Engineering and Sciences Doshisha University Kyoto Japan

formal verification using interactive theorem provers have been noticed as a method of verification of proofs that are too big for humans to check the validity of them. The purpose of this work is to verify the validity of Robertson-type uncertainty relation toward verifying unconditional security of quantum key distributions. We verify the validity of the relation by using proof assistant Coq and it is turned out that the theorem regarding the relation formally holds. The source code for Coq which represents the validity of the theorem is printed in Appendix.

关键词： formal Verification Proof Assistant Coq Uncertainty Relation

关于度量空间的formal balls构成的偏序集

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四川大学学报（自然科学版） 2010年第1期47卷 31-34页

作者：赵红斌四川大学数学学院成都610064

formal ball构成的偏序集为度量空间理论和domain理论提供了联系.作者考察了Ω-范畴的tensor完备化,证明了当度量空间被视为Ω-范畴时,其formal ball构成的偏序集正好是它的tensor完备化.

关键词： formal ball Ω-范畴 Yoneda嵌入 tensor tensor完备化

Study of the Factors Influencing Entrepreneurial Farmers' formal Financial Credit Demand and Credit Constraints in Sichuan and Chongqing

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Asian Agricultural Research 2015年第1期7卷 30-38 43,43页

作者： Yingliang ZHANG Jianfeng ZHANG Guangying LIU College of Economics and Management Southwest University

Based on a survey of 939 farmers in Sichuan and Chongqing,this paper analyzes the influencing factors of entrepreneurial farmers' formal financial credit demands and credit constraints with Probit model. It is found that entrepreneurial farmers have strong demand for formal financial credit,which is mainly production investment demand,but the formal financial credit constraint is obvious. Family size,cognition of loan procedures and conditions have a positive effect on entrepreneurial farmers' formal financial demand,while family per capita income,the distance between family location and the nearest formal financial organization,have negative influence. The relationship between householder'age and entrepreneurial farmers' successful formal loan presents inverted U shape,and educational level presents a negative correlation with successful loan. Compared with the traditional scale agricultural business,farmers engaged in other entrepreneurial businesses would get loan from formal financial institutions more difficultly. Understanding level of the loan procedures and conditions has a positive effect on successful loan. Compared with entrepreneurial farmers without employment,employed farmers are more likely to get loans. Statistically,householder' age and educational level,entrepreneurial business choices do not have significant effect on entrepreneurial households' formal financial credit demands. Family size,family per capital income,the distance between family location and the nearest formal financial organization,and the size of loan do not have significant influence on entrepreneurial households' successful loan. To get rid of formal financial credit constraints,we must implement the incremental reform of financial institutions,promote the formal finance of the villages and towns which can adapt to the farmers' financial demand,and create a good financial environment. Meanwhile,it is necessary to give impetus to innovation of financial management,products and services,reduce credit threshold,and adapt to the c

关键词： Entrepreneurial farmers formal financial credit de

formal Scattering Approach to High-Order Harmonic Generation

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Chinese Physics Letters 1999年第7期16卷 502-504页

作者：高靓辉李晓峰郭东升傅盘铭 Laboratory of Optical Physics Institute of Physics&Center for Condensed Matter PhysicsChinese Academy of SciencesBeijing 100080 Department of Physics Southern University and A&M CollegeBaton RougeLouisiana 70813USA

By using the time-independent formal scattering theoretical approach,we develop a nonperturbative quantum electrodynamics theory to describe high-order harmonic generation(HHG).This theory recovers the semi-classical interpretation of Corkum(Phys.Rev.Lett.71(1993)1994)and gives the same phenomenological cutoff law.The HHG emission rate is expressed as an analytic closed form.We also discuss the connection between HHG and the above threshold ionization from the scattering viewpoint.

关键词： form. formal Harmonic