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Numerical study of plasmas start-up by electron cyclotron waves in NCST spherical tokamak and CN-H1 stellarator
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作者 刘亿卓行 郑平卫 +4 位作者 龚学余 尹岚 陈小昌 钟翊君 杨文军 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第7期12-22,共11页
According to the physics of tokamak start-up,this study constructs a zero-dimensional(0D)model applicable to electron cyclotron(EC)wave assisted start-up in NCST spherical torus(spherical tokamak)and CN-H1 stellarator... According to the physics of tokamak start-up,this study constructs a zero-dimensional(0D)model applicable to electron cyclotron(EC)wave assisted start-up in NCST spherical torus(spherical tokamak)and CN-H1 stellarators.Using the constructed 0D model,the results obtained in this study under the same conditions are compared and validated against reference results for pure hydrogen plasma start-up in tokamak.The results are in good agreement,especially regarding electron temperature,ion temperature and plasma current.In the presence of finite Ohmic electric field in the spherical tokamak,a study on the EC wave assisted start-up of the NCST plasma at frequency of 28 GHz is conducted.The impact of the vertical magnetic field B_(v)on EC wave assisted start-up,the relationship between EC wave injection power P_(inj),Ohmic electric field E,and initial hydrogen atom density n_(H0)are explored separately.It is found that under conditions of Ohmic electric field lower than ITER(~0.3 V m^(-1)),EC wave can expand the operational space to achieve better plasma parameters.Simulating the process of28 GHz EC wave start-up in the CN-H1 stellarator plasma,the plasma current in the zerodimensional model is replaced with the current in the poloidal coil of the stellarator.Plasma startup can be successfully achieved at injection powers in the hundreds of kilowatts range,resulting in electron densities on the order of 10^(17)-10^(18)m^(-3). 展开更多
关键词 spherical torus STELLARATOR electron cyclotron wave start-up 0D model
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Effects of formal credit on pastoral household expense: Evidence from the Qinghai-Xizang Plateau of China
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作者 Yan Zhang Yi Huang +1 位作者 Fan Zhang Zeng Tang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1774-1785,共12页
Formal credit is critical in agricultural production,allowing more expenditure and productive input,thereby improving farmers'welfare.In pastoral China,formal financial institutions are gradually increasing.Howeve... Formal credit is critical in agricultural production,allowing more expenditure and productive input,thereby improving farmers'welfare.In pastoral China,formal financial institutions are gradually increasing.However,a limited understanding remains of how formal credit affects herders'household expenses.Based on a survey of 544 herders from the Qinghai-Xizang Plateau of China,this study adopted the propensity score matching approach to identify the effect of formal credit on herders'total household expenses,daily expenses,and productive expenses.The results found that average age,grassland mortgage,and other variables significantly affected herders'participation in formal credit.Formal credit could significantly improve household expenses,especially productive expenses.A heterogeneity analysis showed that formal credit had a greater impact on the household total expense for those at higher levels of wealth;however,it significantly affected the productive expense of herders at lower wealth levels.Moreover,the mediating effect indicated that formal credit could affect herders'household income,thus influencing their household expenses.Finally,this study suggests that policies should improve herders'accessibility to formal credit. 展开更多
关键词 formal credit herders EXPENSE Qinghai-Xizang Plateau
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A Formal Model for Analyzing Fair Exchange Protocols Based on Event Logic
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作者 Ke Yang Meihua Xiao Zehuan Li 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2641-2663,共23页
Fair exchange protocols play a critical role in enabling two distrustful entities to conduct electronic data exchanges in a fair and secure manner.These protocols are widely used in electronic payment systems and elec... Fair exchange protocols play a critical role in enabling two distrustful entities to conduct electronic data exchanges in a fair and secure manner.These protocols are widely used in electronic payment systems and electronic contract signing,ensuring the reliability and security of network transactions.In order to address the limitations of current research methods and enhance the analytical capabilities for fair exchange protocols,this paper proposes a formal model for analyzing such protocols.The proposed model begins with a thorough analysis of fair exchange protocols,followed by the formal definition of fairness.This definition accurately captures the inherent requirements of fair exchange protocols.Building upon event logic,the model incorporates the time factor into predicates and introduces knowledge set axioms.This enhancement empowers the improved logic to effectively describe the state and knowledge of protocol participants at different time points,facilitating reasoning about their acquired knowledge.To maximize the intruder’s capabilities,channel errors are translated into the behaviors of the intruder.The participants are further categorized into honest participants and malicious participants,enabling a comprehensive evaluation of the intruder’s potential impact.By employing a typical fair exchange protocol as an illustrative example,this paper demonstrates the detailed steps of utilizing the proposed model for protocol analysis.The entire process of protocol execution under attack scenarios is presented,shedding light on the underlying reasons for the attacks and proposing corresponding countermeasures.The developedmodel enhances the ability to reason about and evaluate the security properties of fair exchange protocols,thereby contributing to the advancement of secure network transactions. 展开更多
关键词 Fair exchange protocols FAIRNESS formal analysis logic reasoning
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Numerical Simulation of a Two-Phase Flow with Low Permeability anda Start-Up Pressure Gradient 被引量:1
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作者 Xuanyu Dong Jingyao Yang 《Fluid Dynamics & Materials Processing》 EI 2023年第1期175-185,共11页
A new numerical model for low-permeability reservoirs is developed.The model incorporates the nonlinear characteristics of oil-water two-phase flows while taking into account the initiation pressure gradient.Related n... A new numerical model for low-permeability reservoirs is developed.The model incorporates the nonlinear characteristics of oil-water two-phase flows while taking into account the initiation pressure gradient.Related numerical solutions are obtained using a finite difference method.The correctness of the method is demonstrated using a two-dimensional inhomogeneous low permeability example.Then,the differences in the cumulative oil and water production are investigated for different starting water saturations.It is shown that when the initial water saturation grows,the water content of the block continues to rise and the cumulative oil production gradually decreases. 展开更多
关键词 Low-permeability reservoirs two-phase flow water cut start-up pressure gradient non-darcy flow
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Dynamic evaluation of a scaled-down heat pipe-cooled system during start-up/shut-down processes using a hardware-in-the-loop test approach
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作者 Jiao‑Long Deng Tian‑Shi Wang +3 位作者 En‑Ping Zhu Shuo Yuan Xiao‑Jing Liu Xiang Chai 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第11期174-198,共25页
Micro-mobile heat pipe-cooled nuclear power plants are promising candidates for distributed energy resource power genera-tors and can be flexibly deployed in remote places to meet increasing electric power demands.How... Micro-mobile heat pipe-cooled nuclear power plants are promising candidates for distributed energy resource power genera-tors and can be flexibly deployed in remote places to meet increasing electric power demands.However,previous steady-state simulations and experiments have deviated significantly from actual micronuclear system operations.Hence,a transient analysis is required for performance optimization and safety assessment.In this study,a hardware-in-the-loop(HIL)approach was used to investigate the dynamic behavior of scaled-down heat pipe-cooled systems.The real-time features of the HIL architecture were interpreted and validated,and an optimal time step of 500 ms was selected for the thermal transient.The power transient was modeled using point kinetic equations,and a scaled-down thermal prototype was set up to avoid mod-eling unpredictable heat transfer behaviors and feeding temperature samples into the main program running on a desktop PC.A series of dynamic test results showed significant power and temperature oscillations during the transient process,owing to the inconsistency of the rapid nuclear reaction rate and large thermal inertia.The proposed HIL approach is stable and effective for further studying of the dynamic characteristics and control optimization of solid-state small nuclear-powered systems at an early prototyping stage. 展开更多
关键词 Micro-heat pipe-cooled nuclear reactor HARDWARE-IN-THE-LOOP Dynamic evaluation start-up/shut-down processes
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Formal Modeling of Self-Adaptive Resource Scheduling in Cloud
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作者 Atif Ishaq Khan Syed Asad Raza Kazmi Awais Qasim 《Computers, Materials & Continua》 SCIE EI 2023年第1期1183-1197,共15页
A self-adaptive resource provisioning on demand is a critical factor in cloud computing.The selection of accurate amount of resources at run time is not easy due to dynamic nature of requests.Therefore,a self-adaptive... A self-adaptive resource provisioning on demand is a critical factor in cloud computing.The selection of accurate amount of resources at run time is not easy due to dynamic nature of requests.Therefore,a self-adaptive strategy of resources is required to deal with dynamic nature of requests based on run time change in workload.In this paper we proposed a Cloud-based Adaptive Resource Scheduling Strategy(CARSS)Framework that formally addresses these issues and is more expressive than traditional approaches.The decision making in CARSS is based on more than one factors.TheMAPE-K based framework determines the state of the resources based on their current utilization.Timed-Arc Petri Net(TAPN)is used to model system formally and behaviour is expressed in TCTL,while TAPAAL model checker verifies the underline properties of the system. 展开更多
关键词 formal modeling MULTI-AGENT SELF-ADAPTIVE cloud computing
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Formal Verification Platform as a Service:WebAssembly Vulnerability Detection Application
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作者 LiangJun Deng Hang Lei +6 位作者 Zheng Yang WeiZhong Qian XiaoYu Li Hao Wu Sihao Deng RuChao Sha WeiDong Deng 《Computer Systems Science & Engineering》 SCIE EI 2023年第5期2155-2170,共16页
In order to realize a general-purpose automatic formal verification platform based on WebAssembly technology as a web service(FVPS),which aims to provide an automated report of vulnerability detections,this work build... In order to realize a general-purpose automatic formal verification platform based on WebAssembly technology as a web service(FVPS),which aims to provide an automated report of vulnerability detections,this work builds a Hyperledger Fabric blockchain runtime model.It proposes an optimized methodology of the functional equivalent translation from source program languages to formal languages.This methodology utilizes an external application programming interface(API)table to replace the source codes in compilation,thereby pruning the part of housekeeping codes to ease code inflation.Code inflation is a significant metric in formal language translation.Namely,minor code inflation enhances verification scale and performance efficiency.It determines the efficiency of formal verification,involving launching,running,and memory usage.For instance,path explosion increases exponentially,resulting in out-of-memory.The experimental results conclude that program languages like golang severely impact code inflation.FVPS reduces the wasm code size by over 90%,achieving two orders of optimization magnitude,from 2000 kilobyte(KB)to 90 KB.That means we can cope with golang applications up to 20 times larger than the original in scale.This work eliminates the gap between Hyperledger Fabric smart contracts and WebAssembly.Our approach is pragmatic,adaptable,extendable,and flexible.Nowadays,FVPS is successfully applied in a Railway-Port-Aviation blockchain transportation system. 展开更多
关键词 WebAssembly formal verification blockchain smart contract
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MF2-DMTD: A Formalism and Game-Based Reasoning Framework for Optimized Drone-Type Moving Target Defense
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作者 Sang Seo Jaeyeon Lee +2 位作者 Byeongjin Kim Woojin Lee Dohoon Kim 《Computers, Materials & Continua》 SCIE EI 2023年第11期2595-2628,共34页
Moving-target-defense(MTD)fundamentally avoids an illegal initial compromise by asymmetrically increasing the uncertainty as the attack surface of the observable defender changes depending on spatial-temporal mutation... Moving-target-defense(MTD)fundamentally avoids an illegal initial compromise by asymmetrically increasing the uncertainty as the attack surface of the observable defender changes depending on spatial-temporal mutations.However,the existing naive MTD studies were conducted focusing only on wired network mutations.And these cases have also been no formal research on wireless aircraft domains with attributes that are extremely unfavorable to embedded system operations,such as hostility,mobility,and dependency.Therefore,to solve these conceptual limitations,this study proposes normalized drone-type MTD that maximizes defender superiority by mutating the unique fingerprints of wireless drones and that optimizes the period-based mutation principle to adaptively secure the sustainability of drone operations.In addition,this study also specifies MF2-DMTD(model-checkingbased formal framework for drone-type MTD),a formal framework that adopts model-checking and zero-sum game,for attack-defense simulation and performance evaluation of drone-type MTD.Subsequently,by applying the proposed models,the optimization of deceptive defense performance of drone-type MTD for each mutation period also additionally achieves through mixed-integer quadratic constrained programming(MIQCP)and multiobjective optimization-based Pareto frontier.As a result,the optimal mutation cycles in drone-type MTD were derived as(65,120,85)for each control-mobility,telecommunication,and payload component configured inside the drone.And the optimal MTD cycles for each swarming cluster,ground control station(GCS),and zone service provider(ZSP)deployed outside the drone were also additionally calculated as(70,60,85),respectively.To the best of these authors’knowledge,this study is the first to calculate the deceptive efficiency and functional continuity of the MTD against drones and to normalize the trade-off according to a sensitivity analysis with the optimum. 展开更多
关键词 Moving-target-defense(MTD) DRONE formal methods game theory
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Generativity of Self-Organizing Processes and Their Correlative Description in Terms of a Formal Language of Meta-Ordinal Generative Nature, in the Light of the Maximum Ordinality Principle and the Explicit Solution to the “Three-Body Problem”
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作者 Corrado Giannantoni 《Journal of Applied Mathematics and Physics》 2023年第10期3159-3202,共44页
The main objective of this paper is to demonstrate that the internal processes of Self-Organizing Systems represent a unique and singular process, characterized by their specific generativity. This process can be mode... The main objective of this paper is to demonstrate that the internal processes of Self-Organizing Systems represent a unique and singular process, characterized by their specific generativity. This process can be modeled using the Maximum Ordinality Principle and its associated formal language, known as the “Incipient” Differential Calculus (IDC). 展开更多
关键词 Maximum Ordinality Principle Solution to the “Three-Body Problem” Generativity of Self-Organizing Processes formal Language of Ordinal Generativity formal Language of Meta-Ordinal Generativity
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Rice vs.Wheat:How Rice Farming Shaped Informal Finance in China
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作者 Zhang Bo Sun Tao 《China Economist》 2023年第3期94-111,共18页
China’s financial system is characterized by the coexistence of both formal and informal finance,and informal finance appears to be more prevalent in the south of the country compared to the north.In this paper,we us... China’s financial system is characterized by the coexistence of both formal and informal finance,and informal finance appears to be more prevalent in the south of the country compared to the north.In this paper,we use the historical demarcation of rice-farming regions and the percentage area of rice sown to ascertain the regional distribution of rice farming in the south and wheat farming in the north in order to analyze the role of rice farming in the evolution of different types of financial institutions in China.We find that rice cultivation has a positive effect on informal financial development,though its impact on formal finance is insignificant.Unlike wheat farming,rice cultivation requires farmers to collaborate during busy farming seasons and necessitates the construction of irrigation systems.Such collaboration helped enhance an acquaintance society,in which both parties to transactions enforced the rules and contract terms of their own initiative,paving the way for informal finance.This paper not only demonstrates the cultural roots of the regional financial disparities in China but also expands the research on the ways in which farming practices from the past have shaped the development of China’s present financial markets. 展开更多
关键词 Rice cultivation informal finance formal finance historical origins
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LANGUAGE CORNER Lesson 3:Authorizing the Handling of Formalities
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《China Today》 2005年第3期78-79,共2页
地点:中国旅行社驻外分社营业部Setting:China Travel Service,Overseas Branch人物:杰克·乔治、黄先生Characters:Jack George and Mr.Huang 会话 Dialogue黄先生:乔治先生,您决定了没有?Mr.Huang:Have you made up your mind,Mr.... 地点:中国旅行社驻外分社营业部Setting:China Travel Service,Overseas Branch人物:杰克·乔治、黄先生Characters:Jack George and Mr.Huang 会话 Dialogue黄先生:乔治先生,您决定了没有?Mr.Huang:Have you made up your mind,Mr.George?乔治:你叫我杰克好了。我决定从上海入境。 展开更多
关键词 中国旅行社 手续费 LANGUAGE CORNER Lesson 3:Authorizing the Handling of formalities
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Relative Ding Projective Modules over Formal Triangular Matrix Rings
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作者 Hongyan Fan Xi Tang 《Journal of Applied Mathematics and Physics》 2023年第6期1598-1614,共17页
Let U be a (B, A)-bimodule, A and B be rings, and be a formal triangular matrix ring. In this paper, we characterize the structure of relative Ding projective modules over T under some conditions. Furthermore, using t... Let U be a (B, A)-bimodule, A and B be rings, and be a formal triangular matrix ring. In this paper, we characterize the structure of relative Ding projective modules over T under some conditions. Furthermore, using the left global relative Ding projective dimensions of A and B, we estimate the relative Ding projective dimension of a left T-module. 展开更多
关键词 formal Triangular Matrix Ring Relative Ding Projective Module Relative Ding Projective Dimension
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Large High Altitude Air Shower Observatory Formally Kicks Off
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《Bulletin of the Chinese Academy of Sciences》 2023年第2期69-70,共2页
The Large High Altitude Air Shower Observatory(LHAASO),a major project as part of China’s national scientific and technological infrastructure,passed the national acceptance assessment and formally went into operatio... The Large High Altitude Air Shower Observatory(LHAASO),a major project as part of China’s national scientific and technological infrastructure,passed the national acceptance assessment and formally went into operation on May 10.Dedicated to cosmic ray observation and research,the design of LHAASO was approved by the national authorities on December 31,2015.Jointly sponsored by the Chinese Academy of Sciences(CAS)and the People’s Government of Sichuan Province,the construction of the principal part of the facility began in 2017 and was completed in 2021. 展开更多
关键词 formalLY ALTITUDE TOR
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双重制度视角下政府补贴对企业研发投入影响悖论的新解与验证 被引量:2
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作者 林春培 朱晓艳 +1 位作者 曾志盛 余传鹏 《管理工程学报》 CSCD 北大核心 2024年第3期108-121,共14页
本文利用中国A股上市公司2008—2020年的样本数据实证考察了政府补贴对企业研发投入的影响,并基于双重视角,即企业外部非正式制度层面的政治关联和内部正式制度层面的股权激励,探讨其对政府补贴与企业研发投入之间关系的调节作用。研究... 本文利用中国A股上市公司2008—2020年的样本数据实证考察了政府补贴对企业研发投入的影响,并基于双重视角,即企业外部非正式制度层面的政治关联和内部正式制度层面的股权激励,探讨其对政府补贴与企业研发投入之间关系的调节作用。研究结果表明:(1)适度的政府补贴有助于促进企业研发投入,即政府补贴对研发投入会产生倒U型影响;(2)政治关联会负向调节政府补贴与研发投入之间的倒U型关系;(3)股权激励与政府补贴之间具有互补作用,不仅能抵消过度补贴可能带来的抑制效应,还能进一步增强补贴初期对企业研发投入的激励效应,将两者的倒U型关系转变为正向线性关系。此外,内生性问题分析结果表明上述结论具有稳健性。该研究结论有助于我国政府合理制定补贴政策,为企业科学使用政府补贴以促进研发活动提供有益启示。 展开更多
关键词 政府补贴 正式制度 非正式制度 研发投入
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法治与形式原则的性能:以形式与实质关系为中心 被引量:1
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作者 侯健 《政治与法律》 北大核心 2024年第5期81-97,共17页
法治理论的争论主题之一是形式与实质的关系,其中涉及形式原则的性能。形式原则的性能可以从三个方面检视:形式性、自足性、充分性。形式原则具有形式性,但是并非纯粹,它们可能关涉法律规范的内容安排以及实质价值在规范内容上的贯彻效... 法治理论的争论主题之一是形式与实质的关系,其中涉及形式原则的性能。形式原则的性能可以从三个方面检视:形式性、自足性、充分性。形式原则具有形式性,但是并非纯粹,它们可能关涉法律规范的内容安排以及实质价值在规范内容上的贯彻效果,它们的解释适用也会受到实质价值的影响。形式原则具有指引法治实践的能力,但是并不自足,其自身无法解决遵守程度和例外问题,也无法消弭不同原则间的内在张力。对于有限、抽象的法治构成目标来说,形式原则可以作为构成条件,然而对于更具实践性的法治实现目标而言,就不敷其用了。法律的形式与实质相互联系,相互塑造。当法治对法律的形式提出要求,实践这种要求难免会牵连法律的实质。法治不可缺少形式原则,但是形式原则并非如通常想象的那样纯粹、自足和万能。 展开更多
关键词 法治 形式原则 形式性 自足性 充分性
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现代逻辑思维对诗性的背离与回归——从罗素、维特根斯坦到伽达默尔 被引量:2
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作者 邓晓芒 《四川大学学报(哲学社会科学版)》 北大核心 2024年第1期52-65,209,共15页
亚里士多德创立的形式逻辑在原始思维中有其“互渗律”的起源,因而是基于语言本身的隐喻本性的,但直到康德,以往的隐喻都被理解为“使陌生变得熟悉”,成为形式逻辑的工具论,隐喻的“使熟悉变成陌生”的创新性一面却被忽视了。弗雷格和... 亚里士多德创立的形式逻辑在原始思维中有其“互渗律”的起源,因而是基于语言本身的隐喻本性的,但直到康德,以往的隐喻都被理解为“使陌生变得熟悉”,成为形式逻辑的工具论,隐喻的“使熟悉变成陌生”的创新性一面却被忽视了。弗雷格和罗素等从逻辑中清除了陌生的东西,使之变得数理化、僵化而无创造性,必然遇到“罗素悖论”而无法自拔;维特根斯坦是一个转折,从早期的分析哲学的逻辑观到晚期摆脱工具主义而转向语言游戏,有了西方逻辑思维从背离诗性到回归诗性的苗头;最后,经过伽达默尔对这一苗头的修正和发挥,将其扩展为诠释学的“语言学转向”,为隐喻和诗性打开了一片广阔的天地。可惜,他受到海德格尔和基督教传统“圣言”的局限,最终未能就此将其创造性的对话学说提升到“语言学之后”的形而上学,而沉陷于传统存在论(本体论)的“物理学之后”中。 展开更多
关键词 形式逻辑 隐喻 诗性 语言游戏 语言学转向
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金融能力、正规信贷约束与农户创业行为 被引量:1
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作者 周才云 刘森 《农林经济管理学报》 北大核心 2024年第1期70-78,共9页
基于金融能力和正规信贷约束视角,利用2017年和2019年CHFS微观数据,通过构建Probit模型实证分析金融能力对农户创业行为的影响,探讨正规信贷约束在金融能力和农户创业行为关系中发挥的中介效应。结果表明:金融能力对农户创业行为具有显... 基于金融能力和正规信贷约束视角,利用2017年和2019年CHFS微观数据,通过构建Probit模型实证分析金融能力对农户创业行为的影响,探讨正规信贷约束在金融能力和农户创业行为关系中发挥的中介效应。结果表明:金融能力对农户创业行为具有显著正向影响,且在考虑内生性的情况下,该结论仍然成立;中介机制检验表明,金融能力能够通过缓解正规信贷约束来促进农户创业行为;异质性分析表明,中、西部地区和三线及以下城市的农户金融能力对其创业行为的影响更为显著。据此,建议建立完善的金融能力培养体系,加大对欠发达地区的政策扶持,且提高正规信贷支持力度。 展开更多
关键词 金融能力 正规信贷约束 农户创业行为 因子分析法 PROBIT模型
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面向知识结构分析的模糊概念格模型 被引量:1
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作者 智慧来 李金海 《软件学报》 EI CSCD 北大核心 2024年第5期2466-2484,共19页
知识空间理论使用数学语言对学习者进行知识评价与学习指导,属于数学心理学的研究范畴.技能与问题是构成知识空间的两个基本要素,深入研究两者之间的关系是知识状态刻画与知识结构分析的内在要求.在当前的知识空间理论研究中,没有明确... 知识空间理论使用数学语言对学习者进行知识评价与学习指导,属于数学心理学的研究范畴.技能与问题是构成知识空间的两个基本要素,深入研究两者之间的关系是知识状态刻画与知识结构分析的内在要求.在当前的知识空间理论研究中,没有明确建立技能与问题之间的双向映射,从而难以提出直观概念意义下的知识结构分析模型,也没有明确建立知识状态之间的偏序关系,不利于刻画知识状态之间的差异,更不利于规划学习者未来的学习路径.此外,现有的成果主要集中在经典的知识空间,没有考虑实际问题中数据的不确定性.为此,将形式概念分析与模糊集引入知识空间理论,建立面向知识结构分析的模糊概念格模型.具体地,分别建立知识空间与闭包空间的模糊概念格模型.首先,建立知识空间模糊概念格,并通过任意两个概念的上确界证明所有概念的外延构成知识空间.引入粒描述的思想定义技能诱导的问题原子粒,由问题原子粒的组合判定一个问题组合是否是知识空间中的一个状态,进而提出由问题组合获取知识空间模糊概念的方法.其次,建立闭包空间模糊概念格,并通过任意两个概念的下确界证明所有概念的外延构成闭包空间.类似地,定义问题诱导的技能原子粒,由技能原子粒的组合判定一个技能组合是否是闭包空间中某一知识状态所需的技能,进而提出由技能组合获取闭包空间模糊概念的方法.最后,通过实验分析问题数量、技能数量、填充因子以及分析尺度对知识空间与闭包空间规模的影响.结论表明知识空间模糊概念不同于现有的任何概念,也不能从其他概念派生而来.闭包空间模糊概念本质上是一种面向属性单边模糊概念.在二值技能形式背景中,知识空间与闭包空间中的状态具有一一对应关系,但这种关系在模糊技能形式背景中并不成立. 展开更多
关键词 形式概念分析 知识空间理论 粒计算 粒描述 模糊概念格
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属性偏序形式结构的数学形式化
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作者 任蕴丽 宋佳霖 +1 位作者 郑存芳 洪文学 《燕山大学学报》 CAS 北大核心 2024年第2期129-137,共9页
属性偏序形式结构,作为一种基于人类认知原理和粒计算思想的知识发现和知识表示新理论,目前已有广泛的应用,但其理论基础缺乏抽象化数学化,这势必影响该理论的系统发展。针对上述问题,研究了属性偏序形式结构的数学形式化描述问题。首先... 属性偏序形式结构,作为一种基于人类认知原理和粒计算思想的知识发现和知识表示新理论,目前已有广泛的应用,但其理论基础缺乏抽象化数学化,这势必影响该理论的系统发展。针对上述问题,研究了属性偏序形式结构的数学形式化描述问题。首先,基于粒计算的思想提出了知识表示的形式化框架。在此基础上,通过定义对象集合的覆盖和最简覆盖,给出属性偏序形式结构的粒和粒群的概念,进而通过对粒衍生出粒群的充要条件的讨论,给出了属性偏序形式结构中的知识结构,从而完成属性偏序形式结构的数学形式化描述。最后,通过具体实例展示了利用数学形式化描述构造属性偏序形式结构的过程,并揭示了该过程所体现的人类认知规律。 展开更多
关键词 形式背景 数学形式化 属性偏序形式结构 粒计算 概念认知学习
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A Natural Language Generation Algorithm for Greek by Using Hole Semantics and a Systemic Grammatical Formalism
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作者 Ioannis Giachos Eleni Batzaki +2 位作者 Evangelos C.Papakitsos Stavros Kaminaris Nikolaos Laskaris 《Journal of Computer Science Research》 2023年第4期27-37,共11页
This work is about the progress of previous related work based on an experiment to improve the intelligence of robotic systems,with the aim of achieving more linguistic communication capabilities between humans and ro... This work is about the progress of previous related work based on an experiment to improve the intelligence of robotic systems,with the aim of achieving more linguistic communication capabilities between humans and robots.In this paper,the authors attempt an algorithmic approach to natural language generation through hole semantics and by applying the OMAS-III computational model as a grammatical formalism.In the original work,a technical language is used,while in the later works,this has been replaced by a limited Greek natural language dictionary.This particular effort was made to give the evolving system the ability to ask questions,as well as the authors developed an initial dialogue system using these techniques.The results show that the use of these techniques the authors apply can give us a more sophisticated dialogue system in the future. 展开更多
关键词 Natural language processing Natural language generation Natural language understanding Dialog system Systemic grammar formalism OMAS-III HRI Virtual assistant Hole semantics
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