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Unified Understanding of Cosmological Energy Fields: Exploring Gravitation, Repulsion, and More
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作者 Pramod Kumar Agrawal 《Natural Science》 2023年第11期263-284,共22页
First, we develop a unitary process that can explain all four physical activations: electromagnetic wave, electromagnetic force, repulsion, and attraction. Second, it is clarified that cosmological and physical entiti... First, we develop a unitary process that can explain all four physical activations: electromagnetic wave, electromagnetic force, repulsion, and attraction. Second, it is clarified that cosmological and physical entities relate to different levels of existence in the universe and, hence, cannot be considered under the same paradigm. We know that biological entities use physical substances as executants;analogously, physical entities use cosmological substances as executants. Therefore, we have introduced new terms for the cosmological substances used as executants in physical activities. Third, this study introduces the primary elements of the cosmological world, such as visibility, forcibility, fullness, and hollowness, and defines them according to their attributes. This study explains how different combinations and placements of primary elements create different cosmological fields. These fields are used in all physical activations. Finally, we explain the entity model and how all physical activations occur. This study concludes that all physical activations use primary elements and follow the same universal law. Therefore, this study addresses the untouched subject of the creation of repulsion and attraction (gravitation). Furthermore, it addresses several cosmic mysteries that are yet to be resolved. 展开更多
关键词 Cause of Gravitation Cause of Repulsion Model of Entity unified Theory Multi-Disciplinary approach
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Reachable set estimation for discrete-time Markovian jump neural networks with unified uncertain transition probability
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作者 Yufeng Tian Wengang Ao Peng Shi 《Journal of Automation and Intelligence》 2023年第3期167-174,共8页
This paper focuses on the reachable set estimation for Markovian jump neural networks with time delay.By allowing uncertainty in the transition probabilities,a framework unifies and enhances the generality and realism... This paper focuses on the reachable set estimation for Markovian jump neural networks with time delay.By allowing uncertainty in the transition probabilities,a framework unifies and enhances the generality and realism of these systems.To fully exploit the unified uncertain transition probabilities,an equivalent transformation technique is introduced as an alternative to traditional estimation methods,effectively utilizing the information of transition probabilities.Furthermore,a vector Wirtinger-based summation inequality is proposed,which captures more system information compared to existing ones.Building upon these components,a novel condition that guarantees a reachable set estimation is presented for Markovian jump neural networks with unified uncertain transition probabilities.A numerical example is illustrated to demonstrate the superiority of the approaches. 展开更多
关键词 Markovian jump neural networks unified uncertain transition probabilities Reachable set estimation Double-boundary approach Vector wirtinger-based summation inequality
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A COMPUTER-AIDED UNIFIED APPROACH TO MODELING PWM AND RESONANT CONVERTERS
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作者 Gao Chao 《Journal of Electronics(China)》 2005年第5期558-563,共6页
This letter puts forward a method of modeling for the steady-state and small signal dynamic analysis on PWM, quasi-resonant and series/(parallel) resonant switching converters based on pulse-waveform integral approach... This letter puts forward a method of modeling for the steady-state and small signal dynamic analysis on PWM, quasi-resonant and series/(parallel) resonant switching converters based on pulse-waveform integral approach. As an example, PWM and quasi-resonant converters are used to discuss the principle of the approach. The results are compared with those in the relative literatures. Computer aided analysis are made to confirm the correctness. 展开更多
关键词 开关转换电路 取样函数 信号动态分析 脉冲微波 积分方程
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A Unified Approach to the Thermodynamics and Quantum Scaling Functions of One-Dimensional Strongly Attractive SU(w) Fermi Gases
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作者 余毅聪 管习文 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第7期41-46,共6页
We present a unified derivation of the pressure equation of states, thermodynamics and scaling functions for the one-dimensional (1D) strongly attractive Fermi gases with SU(w) symmetry. These physical quantities ... We present a unified derivation of the pressure equation of states, thermodynamics and scaling functions for the one-dimensional (1D) strongly attractive Fermi gases with SU(w) symmetry. These physical quantities provide a rigorous understanding on a universality class of quantum criticality characterized by the critical exponents z = 2 and correlation length exponent v= 1/2. Such a universality class of quantum criticality can occur when the Fermi sea of one branch of charge bound states starts to fill or becomes gapped at zero temperature. The quantum critical cone can be determined by the double peaks in specific heat, which serve to mark two crossover temperatures fanning out from the critical point. Our method opens to further study on quantum phases and phase transitions in strongly interacting fermions with large SU ( w) and non-SU ( w ) symmetries in one dimension. 展开更多
关键词 A unified approach to the Thermodynamics and Quantum Scaling Functions of One-Dimensional Strongly Attractive SU
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Cascade adaptive control of uncertain unified chaotic systems
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作者 魏伟 李东海 王京 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第4期165-170,共6页
The chaos control of uncertain unified chaotic systems is considered. Cascade adaptive control approach with only one control input is presented to stabilize states of the uncertain unified chaotic system at the zero ... The chaos control of uncertain unified chaotic systems is considered. Cascade adaptive control approach with only one control input is presented to stabilize states of the uncertain unified chaotic system at the zero equilibrium point. Since an adaptive controller based on dynamic compensation mechanism is employed, the exact model of the unified chaotic system is not necessarily required. By choosing appropriate controller parameters, chaotic phenomenon can be suppressed and the response speed is tunable. Sufficient condition for the asymptotic stability of the approach is derived. Numerical simulation results confirm that the cascade adaptive control approach with only one control signal is valid in chaos control of uncertain unified chaotic systems. 展开更多
关键词 unified chaotic systems cascade adaptive control approach response speed chaos control
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数字服务税的反思与中国选择
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作者 童琪婧 《安徽商贸职业技术学院学报》 2024年第1期49-55,共7页
现行国际税制对数字巨头有效课征不足,数字市场国无法分享数字税收利益。数字服务税作为税收分配的单边新方案,或长期与多边规则共存。考察税制本身,税种归属扑朔迷离导致其合法性存疑,课征门槛的歧视嫌疑引发公平性争议。从与国情的兼... 现行国际税制对数字巨头有效课征不足,数字市场国无法分享数字税收利益。数字服务税作为税收分配的单边新方案,或长期与多边规则共存。考察税制本身,税种归属扑朔迷离导致其合法性存疑,课征门槛的歧视嫌疑引发公平性争议。从与国情的兼容性角度,我国数字税收与税源基本重合,缺失与他国争利的需求;且本土数字企业税负未畸轻于其他企业,无充分的可税性基础;兼考虑政策层面,数字服务税与我国发展目标理念相冲。因此,数字服务税非中国的优良选择。中国税制的现代化转型需要与双支柱多边方案接轨,同时强化央地税收划分中的公平理念,试点探索数据税制度,构建数字平台税源征收制度,在税收分享、税源挖掘、税款稽征上回应现实难题。 展开更多
关键词 数字服务税 税制改革 国际税收规则 统一方案
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汇通中外:二十世纪五六十年代广交会的贸易习惯
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作者 朱天啸 《广东党史与文献研究》 2024年第1期77-88,共12页
广交会是新中国成立后中国对外贸易的重要平台。早期广交会在二十世纪五六十年代逐步积累交易经验,形成一种特有的贸易习惯。这种习惯以“统一对外”为特点,反映了当时的社会主义价值观。交易团统一领导,各口岸协调报价,以统一的价格面... 广交会是新中国成立后中国对外贸易的重要平台。早期广交会在二十世纪五六十年代逐步积累交易经验,形成一种特有的贸易习惯。这种习惯以“统一对外”为特点,反映了当时的社会主义价值观。交易团统一领导,各口岸协调报价,以统一的价格面对外商。广交会从客户和商品两方面建立中外商业的联系。在推销产品的过程中,广交会偏好一些稳定的客户,也会为发展新的客户而做一些调整。其推销的策略可以是主动降价提供优惠,也可以是缩减供货量以维持价格水平,或是推动多个报价相互竞争等。推销的策略主要考虑每一类商品当时的供求关系如何。广交会也收集外商对出口商品的反馈,改进或创新产品,并且深入研究对待客户的各种策略。香港地区等外销地区的消费趋势引导出口商品的设计和生产。这些贸易习惯围绕出口商品的定价和制造展开,体现了外贸当中竞争与合作并存的特点。 展开更多
关键词 广交会 贸易习惯 统一对外 出口贸易 社会主义
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An Overview of the Multi-Band and the Generalized BCS Equations-Based Approaches to Deal with Hetero-Structured Superconductors
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作者 G. P. Malik 《Open Journal of Microphysics》 2018年第2期7-13,共7页
We trace the conceptual basis of the Multi-Band Approach (MBA) and recall the reasons for its wide following for composite superconductors (SCs). Attention is then drawn to a feature that MBA ignores: the possibility ... We trace the conceptual basis of the Multi-Band Approach (MBA) and recall the reasons for its wide following for composite superconductors (SCs). Attention is then drawn to a feature that MBA ignores: the possibility that electrons in such an SC may also be bound via simultaneous exchanges of quanta with more than one ion-species—a lacuna which is addressed by the Generalized BCS Equations (GBCSEs). Based on several papers, we give a concise account of how this approach: 1) despite employing a single band, meets the criteria satisfied by MBA because a) GBCSEs are derived from a temperature-incorporated Bethe-Salpeter Equation the kernel of which is taken to be a “superpropagator” for a composite SC-each ion-species of which is distinguished by its own Debye temperature and interaction parameter and b) the band overlapping the Fermi surface is allowed to be of variable width. GBCSEs so-obtained reduce to the usual equations for the Tc and Δ of an elemental SC in the limit superpropagator → 1-phonon propagator;2) accommodates moving Cooper pairs and thereby extends the scope of the original BCS theory which restricts the Hamiltonian at the outset to terms that correspond to pairs having zero centre-of-mass momentum. One can now derive an equation for the critical current density (j0) of a composite SC at T = 0 in terms of the Debye temperatures of its ions and their interaction parameters— parameters that also determine its Tc and Δs;3) transforms the problem of optimizing j0 of a composite SC, and hence its Tc, into a problem of chemical engineering;4) provides a common canopy for most composite SCs, including those that are usually regarded as outside the purview of the BCS theory and have therefore been called “exceptional”, e.g., the heavy-fermion SCs;5) incorporates s±-wave superconductivity as an in-built feature and can therefore deal with the iron-based SCs, and 6) leads to presumably verifiable predictions for the values of some relevant parameters, e.g., the effective mass of electrons, for the SCs for which it has been employed. 展开更多
关键词 Hetero-Structured SUPERCONDUCTORS MULTI-BAND and Generalized BCS Equations-Based approachES unified Treatment of Cuprates and Fe-Based SUPERCONDUCTORS Quest for Clues about Raising Tc
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正倒向随机微分方程理论基础及相关应用
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作者 吴臻 张德涛 《应用概率统计》 CSCD 北大核心 2023年第3期413-435,共23页
本文从随机微分方程和倒向随机微分方程基本理论和应用背景谈起,结合随机最优控制理论和金融市场中的期权定价理论导出完全耦合的正倒向随机微分方程的形式.进而从该类方程的可解性这一角度出发,对已有的理论方法进行分析和探讨,引入一... 本文从随机微分方程和倒向随机微分方程基本理论和应用背景谈起,结合随机最优控制理论和金融市场中的期权定价理论导出完全耦合的正倒向随机微分方程的形式.进而从该类方程的可解性这一角度出发,对已有的理论方法进行分析和探讨,引入一种非马尔科夫框架下保证解的存在唯一性的“统一框架”方法,给出比较定理、解的高维估计等重要性质,并联系相关偏微分方程系统给出其概率解释.对实际中应用广泛的线性正倒向随机微分方程引入了一种线性变换的方法作为“统一框架”方法的重要补充和完善,使得正倒向随机微分方程的应用更加广泛. 展开更多
关键词 倒向随机微分方程 正倒向随机微分方程 随机控制 统一框架方法 偏微分方程
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A UNIFIED APPROACH TO THE METHOD OF GRADIENT PROJECTION WITH ARBITRARY INITIAL POINT 被引量:2
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作者 赖炎连 韦增欣 《Systems Science and Mathematical Sciences》 SCIE EI CSCD 1991年第3期215-224,共10页
In this paper,we present a family of gradient projection method with arbitrary initialpoint.The formula of search direction in the method is unitary.The convergent conditions ofthe method are given.When the initial po... In this paper,we present a family of gradient projection method with arbitrary initialpoint.The formula of search direction in the method is unitary.The convergent conditions ofthe method are given.When the initial point is feasible,the family of the method contains severalknown algorithms.When the initial point is infeasible,the method is exactly that given in[6].Finally,we give a new method which has global convergence property. 展开更多
关键词 Gradient projection METHOD ARBITRARY INITIAL POINT PENALTY function unified approach family of METHOD with parameters global convergence special case of algorithm
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A Unified Momentum Equation Approach for Computing Flow-Induced Stresses in Structures with Arbitrarily-Shaped Stationary Boundaries
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作者 Haram Yeo Hyungson Ki 《Communications in Computational Physics》 SCIE 2017年第6期39-63,共25页
This article presents a novel monolithic numerical method for computing flow-induced stresses for problems involving arbitrarily-shaped stationary boundaries.A unified momentum equation for a continuum consisting of b... This article presents a novel monolithic numerical method for computing flow-induced stresses for problems involving arbitrarily-shaped stationary boundaries.A unified momentum equation for a continuum consisting of both fluids and solids is derived in terms of velocity by hybridizing the momentum equations of incompressible fluids and linear elastic solids.Discontinuities at the interface are smeared over a finite thickness around the interface using the signed distance function,and the resulting momentum equation implicitly takes care of the interfacial conditions without using a body-fitted grid.A finite volume approach is employed to discretize the obtained governing equations on a Cartesian grid.For validation purposes,this method has been applied to three examples,lid-driven cavity flow in a square cavity,lid-driven cavity flow in a circular cavity,and flow over a cylinder,where velocity and stress fields are simultaneously obtained for both fluids and structures.The simulation results agree well with the results found in the literature and the results obtained by COMSOL Multiphysicsr. 展开更多
关键词 Flow induced stress unified momentum equation monolithic approach smeared interface stationary boundary
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传递对准姿态匹配算法的统一性 被引量:16
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作者 陈凯 鲁浩 +1 位作者 赵刚 闫杰 《中国惯性技术学报》 EI CSCD 2008年第2期127-131,共5页
推导了传递对准中使用的传统姿态匹配算法和现代姿态匹配算法,证明了这两类姿态匹配算法是统一的。首先介绍了传统姿态匹配算法,包括"姿态角匹配法"和"姿态矩阵匹配法"。然后论述了现代姿态匹配算法,包括"量... 推导了传递对准中使用的传统姿态匹配算法和现代姿态匹配算法,证明了这两类姿态匹配算法是统一的。首先介绍了传统姿态匹配算法,包括"姿态角匹配法"和"姿态矩阵匹配法"。然后论述了现代姿态匹配算法,包括"量测失准角匹配法"和"最优姿态匹配法"。"量测失准角匹配法"是一种通过引入量测失准角进行传递对准姿态匹配的算法;"最优姿态匹配法"是对"量测失准角匹配法"的改进和完善。最后,从理论上证明了"姿态角匹配法"和"量测失准角匹配法"是等价的,进而,说明了传统姿态匹配算法和现代姿态匹配算法的统一性。 展开更多
关键词 惯性导航 传递对准 姿态匹配 统一性
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面向方程联立求解的精馏塔模拟与优化一体化算法 被引量:16
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作者 邵之江 张余岳 钱积新 《化工学报》 EI CAS CSCD 北大核心 1997年第1期46-51,共6页
在精馏塔机理模型的基础上,提出了面向方程联立求解的精馏塔模拟与优化一体化算法.精馏塔模型方程的特殊结构使得可以进行一定的变量分解和降维,采用面向方程联立求解的技术,使模拟计算和寻优搜索在同一层迭代中完成,避免了双层法每一... 在精馏塔机理模型的基础上,提出了面向方程联立求解的精馏塔模拟与优化一体化算法.精馏塔模型方程的特殊结构使得可以进行一定的变量分解和降维,采用面向方程联立求解的技术,使模拟计算和寻优搜索在同一层迭代中完成,避免了双层法每一步优化搜索都需进行模型收敛计算的缺点.从而大大提高了计算效率.同时,这样的联立法提供了一种开放式的统一框架.无论是模拟计算、操作优化还是设计优化都可以毫无困难地利用这个灵活的计算结构进行解算.文中用两个计算实例说明了这个方法的有效性. 展开更多
关键词 精馏塔 模拟 面向方程 优化一体化算法 算法
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焊接残余应力对疲劳寿命影响的定量研究 被引量:33
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作者 卞如冈 崔维成 +2 位作者 万正权 李良碧 王铭伟 《船舶力学》 EI 北大核心 2011年第7期776-783,共8页
在以往的研究中,残余应力对疲劳寿命的影响基本上均局限于定性分析,很少给出定量的研究结果。文章基于双参数统一方法,开展了锥柱结合壳处的残余应力对疲劳寿命的定量计算分析,给出了残余应力对疲劳寿命影响范围,并通过试样疲劳试验进... 在以往的研究中,残余应力对疲劳寿命的影响基本上均局限于定性分析,很少给出定量的研究结果。文章基于双参数统一方法,开展了锥柱结合壳处的残余应力对疲劳寿命的定量计算分析,给出了残余应力对疲劳寿命影响范围,并通过试样疲劳试验进行了验证。通过研究,可以看出残余应力没有改变裂纹的扩展趋势,但明显加快了裂纹扩展的过程,明显降低了耐压结构的疲劳寿命。 展开更多
关键词 双参数统一方法 残余应力 锥柱结合壳
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基于双参数统一方法的深海结构物疲劳裂纹扩展影响参数研究 被引量:6
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作者 卞如冈 崔维成 +1 位作者 万正权 黄小平 《船舶力学》 EI 北大核心 2010年第5期516-525,共10页
影响裂纹扩展的因素很多,文章基于作者们在PRADS2007会议上提出的双参数裂纹扩展率一般表达式,分析了裂纹初始形状、初始大小对裂纹扩展的影响。并在该裂纹扩展率公式的基础上,基于改进的Wheeler模型,提出了一个考虑载荷比、载荷次序的... 影响裂纹扩展的因素很多,文章基于作者们在PRADS2007会议上提出的双参数裂纹扩展率一般表达式,分析了裂纹初始形状、初始大小对裂纹扩展的影响。并在该裂纹扩展率公式的基础上,基于改进的Wheeler模型,提出了一个考虑载荷比、载荷次序的双参数统一裂纹扩展率表达式。研究表明,文中给出的双参数裂纹扩展率公式能够考虑初始裂纹的形状、大小对裂纹扩展的影响;建立的过载扩展公式,能够反映过载对裂纹扩展的延滞效应,和高强度钢的疲劳试验结果相比较,两者吻合良好。 展开更多
关键词 双参数裂纹扩展率 初始裂纹 过载
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Web查询技术研究 被引量:12
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作者 孟小峰 曹巍 王珊 《计算机科学》 CSCD 北大核心 2001年第2期1-5,共5页
一、引言 WWW的迅速发展,使其成为全球信息传递与共享的日益重要和最具潜力的资源,如何管理WWW上的大量信息,以满足用户不断增长的高质量的信息需求?WWW作为一种新的环境资源,为新技术的产生开辟了新的领域,同时也为传统技术(如数据库。
关键词 信息检索系统 数据库 WEB 数据查询 WWW
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冷弯型钢截面局部屈曲和AISI规范有效宽度计算的统一法则 被引量:17
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作者 何保康 周天华 《建筑钢结构进展》 2005年第4期6-10,共5页
本文介绍了美国AISI冷弯型钢结构规范关于有效宽度计算的统一法则,并综述了加劲板件、非加劲板件、边缘加劲板件等在各种应力分布状态下的屈曲系数k的计算方法。最后,比较了加劲板件按美国AISI规范和我国规范GB50018有效宽度的计算结果... 本文介绍了美国AISI冷弯型钢结构规范关于有效宽度计算的统一法则,并综述了加劲板件、非加劲板件、边缘加劲板件等在各种应力分布状态下的屈曲系数k的计算方法。最后,比较了加劲板件按美国AISI规范和我国规范GB50018有效宽度的计算结果,二者较为接近。 展开更多
关键词 冷弯型钢 局部屈曲 有效宽度 统一法则
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疲劳裂纹扩展双参数统一方法中门槛值的确定 被引量:3
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作者 卞如冈 崔维成 +1 位作者 万正权 黄小平 《船舶力学》 EI 北大核心 2010年第1期94-100,共7页
疲劳裂纹扩展双参数统一方法是由Sadananda和Vasudevan提出的,并认为,疲劳裂纹的扩展是在两个驱动力Kmax和△K共同作用下发生的,因此,裂纹的扩展存在两个门槛值Kmax,th和△Kth与这两个驱动力相对应。为了使裂纹扩展,必须同时满足两个门... 疲劳裂纹扩展双参数统一方法是由Sadananda和Vasudevan提出的,并认为,疲劳裂纹的扩展是在两个驱动力Kmax和△K共同作用下发生的,因此,裂纹的扩展存在两个门槛值Kmax,th和△Kth与这两个驱动力相对应。为了使裂纹扩展,必须同时满足两个门槛值(Kmax,th;△Kth)的条件。从理论上来说,门槛值可以通过试验来测定,但由于试验测定门槛值存在较多困难。文章基于作者们在PRADS2007会议上提出的双参数裂纹扩展率的一般表达式,给出根据疲劳试验数据确定门槛值的方法,和试验数据相比,吻合较好。 展开更多
关键词 双参数统一方法 门槛值 6013铝合金
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人工智能理论:从分立到统一的奥秘 被引量:16
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作者 钟义信 《北京邮电大学学报》 EI CAS CSCD 北大核心 2006年第3期1-6,共6页
由于智能问题的重要性和复杂性,人们曾经分别从结构、功能和行为等多个不同侧面对自然智能问题展开了模拟研究,于20世纪形成了人工智能的结构主义、功能主义和行为主义3个有代表性的理论.这些理论分别都取得了很大的成功,然而它们之间... 由于智能问题的重要性和复杂性,人们曾经分别从结构、功能和行为等多个不同侧面对自然智能问题展开了模拟研究,于20世纪形成了人工智能的结构主义、功能主义和行为主义3个有代表性的理论.这些理论分别都取得了很大的成功,然而它们之间却难以互相沟通和互相认可.为此,提出了一种新的研究途径———从智能生成的共性核心机制入手探讨智能的本质,称为“机制主义”.研究发现:一般情形下,智能生成的核心机制表现为“信息—知识—智能的转换”;而且,结构主义、功能主义、行为主义三者能在“机制主义”框架下得到和谐的统一.这可为人工智能理论的未来发展提供新的认识和新的方向. 展开更多
关键词 结构主义 功能主义 行为主义 机制主义 人工智能统一理论
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机制主义:人工智能的统一理论 被引量:17
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作者 钟义信 《电子学报》 EI CAS CSCD 北大核心 2006年第2期317-321,共5页
长期以来,学术界曾经分别从智力系统的结构、功能和行为三个不同的侧面分析和模拟人的智力过程,取得了众多成果,形成了人工智能理论的结构主义、功能主义和行为主义三大体系.这些研究也留下许多问题,而且互相缺乏沟通,常常发生“孰优孰... 长期以来,学术界曾经分别从智力系统的结构、功能和行为三个不同的侧面分析和模拟人的智力过程,取得了众多成果,形成了人工智能理论的结构主义、功能主义和行为主义三大体系.这些研究也留下许多问题,而且互相缺乏沟通,常常发生“孰优孰劣”的争论.本文试图提出智能生成的“机制主义”,希望从智能生成的共性机制入手探讨智能的本质.研究发现:在一般情形下,智能生成机制表现为“信息-知识-智能的转换”,由此引出了“知识理论”;特别有意义的是,结构主义、功能主义、行为主义三者可以在“机制主义”框架下得到和谐完美的统一.这可能为智能科学技术的发展提供新的理解,带来新的机会. 展开更多
关键词 结构主义 功能主义 行为主义 机制主义 人工智能统一理论
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