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Likely Limit Sets of a Class of p-order Feigenbaum's Maps 被引量:1
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作者 WANG WEI LIAO LI 《Communications in Mathematical Research》 CSCD 2012年第2期137-145,共9页
A continuous map from a closed interval into itself is called a p-order Feigenbaum's map if it is a solution of the Feigenbaum's equation fP(λx)=λf(x). In this paper, we estimate Hausdorff dimensions of likely... A continuous map from a closed interval into itself is called a p-order Feigenbaum's map if it is a solution of the Feigenbaum's equation fP(λx)=λf(x). In this paper, we estimate Hausdorff dimensions of likely limit sets of some p-order Feigenbaum's maps. As an application, it is proved that for any 0 〈 t 〈 1, there always exists a p-order Feigenbaum's map which has a likely limit set with Hausdorff dimension t. This generalizes some known results in the special case of p =2. 展开更多
关键词 Feigenbaum's equation Feigenbaum's map likely limit set Hausdorff dimension
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Access to novel anti-diabetic agents in resource limited settings:A brief commentary
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作者 Poobalan Naidoo Kiolan Naidoo +1 位作者 Sumanth Karamchand Rory F Leisegang 《World Journal of Diabetes》 SCIE 2023年第7期939-941,共3页
The prevalence of diabetes mellitus is increasing in resource limited settings.Simultaneously,there has been an increase in the number of novel therapies for the management of diabetes mellitus.However,use of novel an... The prevalence of diabetes mellitus is increasing in resource limited settings.Simultaneously,there has been an increase in the number of novel therapies for the management of diabetes mellitus.However,use of novel antidiabetic therapies is limited because of major market access challenges in resource limited settings.Niching products to those patients with the highest absolute risk for major adverse cardiovascular outcomes,and thus most likely to benefit from the therapy,are less likely to have negative budget impact for funders.To improve access,and reduce morbidity and mortality,requires alignment amongst key stakeholders including patient advocacy groups,health care professional councils,national departments of health,the pharmaceutical industry,treasury and finance departments. 展开更多
关键词 Type 2 diabetes mellitus Novel anti-diabetic agents Resource limited settings ACCESS
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Exclusive Fibula Osteosynthesis for Treating Open Fractures Gustillo I-III B of the Distal Half of the Leg Bones in a Resources-Limited Setting
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作者 Georges Kuyigwa Toha Paul Munguakonkwa Budema +2 位作者 Ona Longombe Ahuka Akinja Bitum Uwonda Jean Marie Vianney Kabangu Tshimbila 《Open Journal of Orthopedics》 2023年第3期108-121,共22页
Introduction: Management of open leg bones fractures is a challenging health issue for the surgeon, particularly true in resource-limited settings. In this study, we evaluate exclusive fibular osteosynthesis in the tr... Introduction: Management of open leg bones fractures is a challenging health issue for the surgeon, particularly true in resource-limited settings. In this study, we evaluate exclusive fibular osteosynthesis in the treatment of open fractures of the distal half of the leg bones as a therapeutic option in our context. Methods: This is a prospective, experimental, multicenter study of 30 open fractures of the distal half of the leg bones treated with exclusive fibula osteosynthesis, conducted in 3 hospitals in the DRC from January 1, 2013 to September 30, 2016. Results: The age range of 20 to 40 years grouped 22 (73.4%) patients, the sex ratio was 1:1 and the unemployed were the most involved with 16 (53.3%) cases. The Gustilo II, I, III B and III A types represented 40%, 33.3%, 20% and 6.7%, respectively. The fractures were located in the distal third in 12 (40%) cases, in the middle third in 11 (36.7%) cases, and in both malleoli in 7 cases (23.3%). Osteosynthesis of the fibula by screw plate was applied in 22 (73.3%) patients and pinning in 8 (26.7%). Satisfactory reduction of the tibial fracture site was achieved in 29 (96.7%) cases and 100% bone healing was achieved within an average of 10 weeks. Four (13.3%) loss of alignment, 1 (3.3%) infection, 1 (3.3%) skin necrosis and 2 (6.7%) ankle stiffness complicated our fractures. Conclusion: Exclusive osteosynthesis of the fibula as a common technique for fractures of the distal half of the leg bones allowed us to reduce, immobilize and consolidate the tibial fracture in the required time and to preserve the mobility of the ankle. 展开更多
关键词 Fibular Exclusive Osteosynthesis Open Tibial Fractures Resources limited settings Tibial Fracture Consolidation
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Attractor, chain recurrent set and limit set of flow
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作者 郑作环 《Science China Mathematics》 SCIE 2000年第3期244-251,共8页
The properties of attractor, chain recurrent set and limit set of the flow on a compact metric space are studied.
关键词 FLOW ATTRACTOR chin recurrent set limit set
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On Limit Sets and Discreteness Criteria for Nonelementary Subgroups of M(~n)
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作者 Bin Lin DAI Ai Nong FANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2005年第3期465-472,共8页
In this paper, we will study the nonelementary groups of MSbius transformations in R^n and some properties are obtained. Also in this paper we will prove several theorems about discreteness criteria and group converge... In this paper, we will study the nonelementary groups of MSbius transformations in R^n and some properties are obtained. Also in this paper we will prove several theorems about discreteness criteria and group convergence of nonelementary groups of M(R^n). 展开更多
关键词 limit set Nonelementary group Discrete group Isometry group
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Limit Set Problem of Multi-Agent Systems with Finite States: An Eigenvalue-Based Approach
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作者 WANG Lin WANG Xiaofan WANG Jinhuan 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2015年第3期570-579,共10页
This paper studies the limit set of multi-agent system with finite states, in which the system is converted into a linear system through an expansion of space. Then, the structure properties of the system matrix are i... This paper studies the limit set of multi-agent system with finite states, in which the system is converted into a linear system through an expansion of space. Then, the structure properties of the system matrix are investigated, and the relationships between the eigenvalues and the limit set are developed. As an application, the nilpotent problem of elementary cellular automata(ECA) known as algorithmically undecidable is considered, and all the nilpotent ECA are found out which consists of rules 0, 8, 64, 239, 253, 255. 展开更多
关键词 Cellular automata EIGENVALUE finite states limit set multi-agent system nilpotent.
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SOME PROPERTIES OF BOUNDED SETS IN INDUCTIVE LIMITS
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作者 丘京辉 《苏州大学学报(自然科学版)》 CAS 1991年第2期109-114,共6页
Let (E,ξ)=indlim (En,ξn) be an inductive limit of a sequence of locally convex spaces,For brevity,denote by (DS) each set Bbounded in (E,ξ) is contained in some En; and (DST) each set B bounded in (E,ξ) is co... Let (E,ξ)=indlim (En,ξn) be an inductive limit of a sequence of locally convex spaces,For brevity,denote by (DS) each set Bbounded in (E,ξ) is contained in some En; and (DST) each set B bounded in (E,ξ) is contained and bounded in some (En,ξn). Theovem 1.(DS) holds provided that (i) for each n∈N,there is a neighborhood Un of o in (En,ξn) and m(n)∈ such that -↑Un^E包含于Em(n),and (ii) for any neighborhood V n of o in (En,ξn),∞↑Un=1 Vn absorbs every bounded set in (E,ξ). theorem 2 Let all (En,ξn) be metrizable and (DS) hold,then for each bounded set B IN (E,ξ)and each n ∈N thcrc is a neighborhood U k of o in (Ek,ξk), 1≤k≤n ,and m(n)∈N such that ——↑(B+U1+U2+…+Un)^E包含于 Em(n). theorem 3. Let all (En,ξn) be Frechet spaces.Then (DST) holds if and only if (i) for each n ∈N,there is u neighborhood U n of in (En,ξn) and m(n)∈N such that 0↑Un^E包含于Em(n),and (ii) for each each closed ,absosed,absolutely conuex,bounded set B in (E,ξ),∞↑Un=1((εnB)∩Un)absorbs B,where U n is any neighborhood of o in (En,ξn) and εn is any positive number for every n ∈N。 展开更多
关键词 有界集 归纳极限 凸空间 线性拓扑空间
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LIMITING DIRECTIONS OF JULIA SETS OF ENTIRE SOLUTIONS TO COMPLEX DIFFERENTIAL EQUATIONS 被引量:2
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作者 王珺 陈宗煊 《Acta Mathematica Scientia》 SCIE CSCD 2017年第1期97-107,共11页
In this paper,we mainly investigate the dynamical properties of entire solutions of complex differential equations.With some conditions on coefficients,we prove that the set of common limiting directions of Julia sets... In this paper,we mainly investigate the dynamical properties of entire solutions of complex differential equations.With some conditions on coefficients,we prove that the set of common limiting directions of Julia sets of solutions,their derivatives and their primitives must have a definite range of measure. 展开更多
关键词 limiting direction Julia set entire function linear differential equation defi-ciency
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Accurate equilibrium inversion barrier of ammonia by extrapolation to the one-electron basis set limit
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作者 李永庆 宋朋 马凤才 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第2期211-215,共5页
A scheme based on treating uniform singlet-pair and triplet-pair interactions is suggested to extrapolate electron correlation energy of ammonia, calculated at two basis-set levels of ab initio theory in the infinite ... A scheme based on treating uniform singlet-pair and triplet-pair interactions is suggested to extrapolate electron correlation energy of ammonia, calculated at two basis-set levels of ab initio theory in the infinite one-electron basis-set limit. The dual-level method is tested on the extrapolation of the full correlation in coupled-cluster singles and doubles and in the case also a noniterative perturbative correction for connected triple energies for the C3v and D3h structures of ammonia, with correlation-consistent basis sets of the type cc-pVXZ (X = D, T, Q, 5, 6) and aug-cc-pVXZ (X = D, T, Q, 5). For testing and comparison purposes, the energies reported by Klopper [J. Comput. Chem. 22 1306 (2001)] have been taken. From a corresponding extrapolation of CCSD(T)/AVXZ energies for X = 4, 5, we obtain total inversion barriers of 1833.87 cm-1/1832.33 cm^-1 for the two/three-parameter extrapolation rules, which are in good agreement with other theoretical extrapolation and empirical values in the literature. 展开更多
关键词 inversion barrier AMMONIA complete basis set limit LOW-COST
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Use of Dried Blood Spot to Improve the Diagnosis and Management of HIV in Resource-Limited Settings
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作者 Chatté Adawaye Erick Kamangu +3 位作者 Ali Mahamat Moussa Bertin Tchoumbou Dolores Vaira Michel Moutschen 《World Journal of AIDS》 2013年第3期251-256,共6页
Over 75% of people infected with HIV live in countries where health resources are very limited for the diagnosis and biological monitoring of people infected by the virus. In resource-limited settings, the use of DBS ... Over 75% of people infected with HIV live in countries where health resources are very limited for the diagnosis and biological monitoring of people infected by the virus. In resource-limited settings, the use of DBS is a valuable alternative. It has provided technical and economical alternative to the collection of blood in the tubes for testing HIV infection. The DBS can be kept for over a year, it is economical in storage space and facilitates storage conditions because it can be stored at room temperature. It is more discreet and easier to carry over liquid samples that require tubes and other appropriate materials. The amount is sufficient for certain analyses of DNA generally, but may be insufficient for the analysis of viral RNA if the viral load is low. Its disadvantage is often associated with small amounts of blood collected available for testing, and the difficulties encountered in laboratories to extract the maximum possibilities without material contamination. DBS can be stored at room temperature (25℃ - 35℃), at 4℃, -20℃ or even -70℃. With PCR, the DBS is a suitable medium for the diagnosis of patients infected with HIV, virological monitoring by the VL and even analyzing viral genotype. It is a handy stand for the collection, transport and analyses of biological monitoring of HIV infection. It is indeed very suitable for environments with limited accessibility where it is difficult for specialized laboratories to monitor these patients. The DBS is suitable for resource-limited settings. 展开更多
关键词 DBS HIV Resources limitED setTING VIRAL Load GENOTYPING
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Fountain Set Limited Launched New Products of 2011 Autumn-Winter Collections:Eco-friendliness and Multi-category
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作者 LiuYi 《China Textile》 2010年第11期16-16,共1页
Fountain Set Limited announced that its branch brand'Fountain Set' was producing 2011 autumn-winter collections on the 2010 Intertextile Shanghai Apparel Fabrics Trade Fair,displaying new products
关键词 Eco Fountain set limited Launched New Products of 2011 Autumn-Winter Collections
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大学生使用微信朋友圈限时动态设置动因和影响研究 被引量:1
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作者 高慧月 《情报探索》 2024年第2期90-98,共9页
【目的/意义】旨在探究大学生微信用户使用限时动态设置的动因和影响。【方法/过程】采用质化半结构化访谈的研究方法,对微信朋友圈使用限时动态设置的30名大学生用户进行了半结构化访谈。【结果/结论】微信平台因素(隐私威胁、语境消... 【目的/意义】旨在探究大学生微信用户使用限时动态设置的动因和影响。【方法/过程】采用质化半结构化访谈的研究方法,对微信朋友圈使用限时动态设置的30名大学生用户进行了半结构化访谈。【结果/结论】微信平台因素(隐私威胁、语境消解、替代性社交方案)和用户个人因素(印象管理、感知控制、生活变迁、从众心理)是影响用户选择使用朋友圈限时动态设置的主要因素。与此同时,用户使用朋友圈限时动态设置后感知到的使用成本(呈现阻碍、印象偏差、不利于弱关系的拓展)和使用收益(便捷管理、回归现实生活)又会对用户限时动态设置的使用行为产生影响。 展开更多
关键词 微信朋友圈 限时动态设置 动因 影响
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COMPLEXITY OF LIMIT LANGUAGE OF THE ELEMENTARY CELLULAR AUTOMATON OF RULE 22
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作者 Jiang Zhisong Wang Yi 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2005年第3期268-276,共9页
In this paper, the limit set of the elementary cellular automaton of rule 22 is considered. The limit language is defined from limit set and its complexity is studied by using formal language theory. It is proved that... In this paper, the limit set of the elementary cellular automaton of rule 22 is considered. The limit language is defined from limit set and its complexity is studied by using formal language theory. It is proved that this language is not a regular language. This result shows that the dynamics of this cellular automaton is actually complicated. 展开更多
关键词 COMPLEXITY cellular automaton limit set limit language.
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集成方法在极限学习机中的应用
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作者 高浩森 李凤莲 +2 位作者 张明泽 李晓辉 贾文辉 《电子设计工程》 2024年第12期32-36,共5页
针对传统的单一机器学习模型对非平衡数据集分类预测性能偏低的问题,通过用Adaboost策略将传统的最大化Gm代价调整极限学习机集成起来,生成一种最大化Gm集成极限学习机分类模型(MG-CCR-EELM),使其能够适用于不同平衡率非平衡数据集的分... 针对传统的单一机器学习模型对非平衡数据集分类预测性能偏低的问题,通过用Adaboost策略将传统的最大化Gm代价调整极限学习机集成起来,生成一种最大化Gm集成极限学习机分类模型(MG-CCR-EELM),使其能够适用于不同平衡率非平衡数据集的分类。通过与现有的最大化Gm代价调整极限学习机、代价敏感混合属性多决策树、改进的模糊支持向量机、随机森林等用于非平衡数据集的分类模型的实验对比,MG-CCR-EELM模型在UCI公共数据集上的准确率最高可提升3.01%,在经颅多普勒数据集上的分类预测准确率提升了5.67%,验证了MG-CCR-EELM模型是一种有效的集成学习模型。 展开更多
关键词 集成学习 代价调整极限学习机 非平衡数据集 分类预测
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青年用户使用朋友圈限时动态设置影响因素研究——基于扎根理论的探索性研究
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作者 高慧月 《图书情报导刊》 2024年第7期26-35,共10页
深入理解青年微信用户使用朋友圈限时动态设置的影响因素,可为相关研究和社交平台的功能优化提供有价值的参考。采用扎根理论方法,通过半结构化访谈收集了30位青年微信用户的资料,经三级编码分析发现:用户选择使用限时动态设置的前因因... 深入理解青年微信用户使用朋友圈限时动态设置的影响因素,可为相关研究和社交平台的功能优化提供有价值的参考。采用扎根理论方法,通过半结构化访谈收集了30位青年微信用户的资料,经三级编码分析发现:用户选择使用限时动态设置的前因因素包括社交平台因素和用户个人因素,而使用该设置的后果因素包括使用成本和使用收益;4个因素都会影响用户的使用行为。 展开更多
关键词 青年用户 限时动态设置 影响因素 扎根理论 探索性研究
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NON-WANDERING SET OF A CONTINUOUS GRAPH MAP
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作者 GuRongbao SunTaixiang ZhengTingting 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2003年第4期477-481,共5页
The non-wandering set Ω(f) for a graph map f is investigated. It is showed that Ω(f) is contained in the closure of the set ER(f) of eventually recurrent points of f and ω-limit set ω(Ω(f)) of Ω(f) is containe... The non-wandering set Ω(f) for a graph map f is investigated. It is showed that Ω(f) is contained in the closure of the set ER(f) of eventually recurrent points of f and ω-limit set ω(Ω(f)) of Ω(f) is contained in the closure of the set R(f) of recurrent points of f. 展开更多
关键词 graph map recurrent point eventually recurrent point ω-limit set non-wandering set
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花铃期不同灌溉处理对棉花光合特性和产量的影响
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作者 齐文婷 薛皓文 +4 位作者 王政钧 王航 马晓鹏 肖娟 王建东 《棉花学报》 CSCD 北大核心 2024年第4期340-352,共13页
【目的】揭示花铃期不同灌水下限对棉花叶片光合特征参数及产量的影响,为新疆北疆植棉区灌溉制度的优化提供参考。【方法】2023年在新疆昌吉开展大田试验,以中棉所125为供试品种,在花铃期设置3种灌水下限,分别为55%(T1)、60%(T2)和70%(... 【目的】揭示花铃期不同灌水下限对棉花叶片光合特征参数及产量的影响,为新疆北疆植棉区灌溉制度的优化提供参考。【方法】2023年在新疆昌吉开展大田试验,以中棉所125为供试品种,在花铃期设置3种灌水下限,分别为55%(T1)、60%(T2)和70%(T3)田间持水量,以当地常规的滴灌模式作为对照(CK),分析不同处理对花铃期土壤含水率、棉花叶片光合特性及产量性状的影响,并探究了光合指标与叶面温度和气象因子之间的相关关系和回归关系。【结果】花铃期T3处理的0~60 cm土层土壤含水率维持在相对较高且稳定的范围(18.5%~21.6%)。花铃前期(7月11日),T3处理的净光合速率日平均值最大,呈升-降-升-降的日变化趋势。相关分析表明,净光合速率、蒸腾速率均与0~60 cm土层土壤含水率、叶面温度、太阳辐射强度和环境温度呈显著正相关关系。T3处理的籽棉产量和灌溉水利用效率最高,分别较CK显著提高26.46%和71.43%。基于秩和比法的多目标综合评价表明,T3处理的综合效果最优。【结论】在水资源短缺的北疆膜下滴灌棉田,花铃期灌水下限、上限分别设置为70%、90%田间持水量可以实现节水且高产。 展开更多
关键词 棉花 土壤含水率 花铃期 光合特性 产量 灌水下限 田间持水量
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基于系统协调度模型的汛限水位分期控制
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作者 冯佳宁 李晓英 +1 位作者 张琰 张梦仙 《长江科学院院报》 CSCD 北大核心 2024年第1期9-17,共9页
为协调防洪与兴利的矛盾,提高洪水资源化利用效益,基于改进模糊集方法进行汛期分期,建立系统协调度模型并计算得到汛限水位的动态控制域。以思林水库为例,前、后汛期的汛限水位与发电效益协同贡献度成正比,与防洪风险协同贡献度成反比;... 为协调防洪与兴利的矛盾,提高洪水资源化利用效益,基于改进模糊集方法进行汛期分期,建立系统协调度模型并计算得到汛限水位的动态控制域。以思林水库为例,前、后汛期的汛限水位与发电效益协同贡献度成正比,与防洪风险协同贡献度成反比;为实现系统协调度最大,前、后汛期的汛限水位动态控制域应分别为[435,437]m和[435,438]m,前、后汛期可分别增发电量2169.907×10^(4)、6509.722×10^(4)kW·h,水资源利用量可分别提高0.716×10^(8)、1.079×10^(8)m^(3)。研究成果可提高洪水资源利用效率,为水库安全合理运行提供参考。 展开更多
关键词 汛限水位 汛期分期 改进模糊集分析法 动态控制域 系统协调度
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工程结构椭球凸集模型可靠度的二次型计算方法研究
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作者 冉志红 凌枫 +2 位作者 董国华 谢璐源 林帆 《四川建筑科学研究》 2024年第2期25-31,共7页
工程结构概率可靠度在理论上已经建立了完整的计算体系,但在实际工程应用中却停留在近似或半经验阶段。对于既有工程结构的可靠度评估,由于测试数据有限,采用椭球凸集模型可靠度进行评估有很高的工程价值和广泛的应用前景。椭球凸集模... 工程结构概率可靠度在理论上已经建立了完整的计算体系,但在实际工程应用中却停留在近似或半经验阶段。对于既有工程结构的可靠度评估,由于测试数据有限,采用椭球凸集模型可靠度进行评估有很高的工程价值和广泛的应用前景。椭球凸集模型可靠度有很多种不同的定义,但无论何种定义,如果完全脱离概率可靠度与失效概率的基本假定,则很难与现在基于概率可靠度评估方法的主流实现有效的衔接。从多维正态联合概率密度出发,推导了斜椭球方程及其标准化方法,同时结合极限状态方程,给出了椭球凸集模型可靠度与概率可靠度之间的数学关系。算例表明,得出的特殊简化情况下的椭球凸集模型可靠度计算方法和几何解释,可进一步推动该类可靠度在工程中的应用。 展开更多
关键词 结构可靠度 椭球凸集模型 工程结构可靠度 极限状态方程
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Traffic Flow Data Forecasting Based on Interval Type-2 Fuzzy Sets Theory 被引量:5
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作者 Runmei Li Chaoyang Jiang +1 位作者 Fenghua Zhu Xiaolong Chen 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI 2016年第2期141-148,共8页
This paper proposes a long-term forecasting scheme and implementation method based on the interval type-2 fuzzy sets theory for traffic flow data. The type-2 fuzzy sets have advantages in modeling uncertainties becaus... This paper proposes a long-term forecasting scheme and implementation method based on the interval type-2 fuzzy sets theory for traffic flow data. The type-2 fuzzy sets have advantages in modeling uncertainties because their membership functions are fuzzy. The scheme includes traffic flow data preprocessing module, type-2 fuzzification operation module and long-term traffic flow data forecasting output module, in which the Interval Approach acts as the core algorithm. The central limit theorem is adopted to convert point data of mass traffic flow in some time range into interval data of the same time range (also called confidence interval data) which is being used as the input of interval approach. The confidence interval data retain the uncertainty and randomness of traffic flow, meanwhile reduce the influence of noise from the detection data. The proposed scheme gets not only the traffic flow forecasting result but also can show the possible range of traffic flow variation with high precision using upper and lower limit forecasting result. The effectiveness of the proposed scheme is verified using the actual sample application. © 2014 Chinese Association of Automation. 展开更多
关键词 Data handling Forecasting Fuzzy sets Membership functions Uncertainty analysis
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