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Mathematical Modeling of Possibility Markov Chains by Possibility Theory
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作者 Yoshiki Uemura Takemura Kazuhisa Kenji Kita 《Applied Mathematics》 2024年第8期499-507,共9页
Statistical regression models are input-oriented estimation models that account for observation errors. On the other hand, an output-oriented possibility regression model that accounts for system fluctuations is propo... Statistical regression models are input-oriented estimation models that account for observation errors. On the other hand, an output-oriented possibility regression model that accounts for system fluctuations is proposed. Furthermore, the possibility Markov chain is proposed, which has a disidentifiable state (posterior) and a nondiscriminable state (prior). In this paper, we first take up the entity efficiency evaluation problem as a case study of the posterior non-discriminable production possibility region and mention Fuzzy DEA with fuzzy constraints. Next, the case study of the ex-ante non-discriminable event setting is discussed. Finally, we introduce the measure of the fuzzy number and the equality relation and attempt to model the possibility Markov chain mathematically. Furthermore, we show that under ergodic conditions, the direct sum state can be decomposed and reintegrated using fuzzy OR logic. We had already constructed the Possibility Markov process based on the indifferent state of this world. In this paper, we try to extend it to the indifferent event in another world. It should be noted that we can obtain the possibility transfer matrix by full use of possibility theory. 展开更多
关键词 Possibility markov chain Ergodic Condition Direct Sum State Prior Indiscriminate State Posterior Discriminatory State
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One-dimensional Chain Dibenzo-18-crown-6 Complex: [K(DB18-C-6)]_2[Pt(SCN)_6]·2H_2O·C_2H_4Cl_2 Assembled by Cation-π Interactions 被引量:1
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作者 ZHUYue-hua DUMao-xi +2 位作者 LIDa-cheng WANGDa-qi DOUJian-min 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第1期123-126,共4页
关键词 one-dimensional chain Crown ether complex Cation-π interactions Synthesis and crystal structure
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A New One-dimensional Chain Compound Constructed by {Mo_8O_(28)} units via Corner-sharing 被引量:1
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作者 YUYa-Qin YANGWen-Bin WUChuan-De LUCan-Zhong 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第2期214-218,共5页
The title compound, {(H3O)4(NH4)4[Mo8O28]?2H2O}n 1, has been synthesized from the reaction of Zn(OAc)2 and (NH4)6Mo7O24?4H2O in aqueous solution at ambient tempe- rature, and its crystal structure was determined by ... The title compound, {(H3O)4(NH4)4[Mo8O28]?2H2O}n 1, has been synthesized from the reaction of Zn(OAc)2 and (NH4)6Mo7O24?4H2O in aqueous solution at ambient tempe- rature, and its crystal structure was determined by X-ray single-crystal analysis with the following crystallographic data: monoclinic system, space group P21/n, a = 9.5234(6), b = 11.3235(8), c = 14.8812(10) ?, β = 107.467(2)o, V = 1530.77(18) ?3, Z = 4, F(000) = 1336, μ = 3.293 mm-1 and Dc = 3.037 g/cm3. The final R = 0.0619 for 2691 observed reflections (I > 2σ(I)). X-ray crys- tal structure analysis showed that the novel one-dimensional chain compound is built up by basic {Mo8O28} units via single μ2-O, and such chains are further linked into a three-dimensional net- work by hydrogen bonds. 展开更多
关键词 polyoxomolybdate octamolybdate one-dimensional chain
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Forecast future disasters using hydro-meteorological datasets in the Yamuna river basin,Western Himalaya:Using Markov Chain and LSTM approaches
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作者 Pankaj Chauhan Muhammed Ernur Akiner +1 位作者 Rajib Shaw Kalachand Sain 《Artificial Intelligence in Geosciences》 2024年第1期114-136,共23页
This research aim to evaluate hydro-meteorological data from the Yamuna River Basin,Uttarakhand,India,utilizing Extreme Value Distribution of Frequency Analysis and the Markov Chain Approach.This method assesses persi... This research aim to evaluate hydro-meteorological data from the Yamuna River Basin,Uttarakhand,India,utilizing Extreme Value Distribution of Frequency Analysis and the Markov Chain Approach.This method assesses persistence and allows for combinatorial probability estimations such as initial and transitional probabilities.The hydrologic data was generated(in-situ)and received from Uttarakhand Jal Vidut Nigam Limited(UJVNL),and meteorological data was acquired from NASA’s archives MERRA-2 product.A total of sixteen years(2005-2020)of data was used to foresee daily Precipitation from 2020 to 2022.MERRA-2 products are utilized as observed and forecast values for daily Precipitation throughout the monsoon season,which runs from July to September.Markov Chain and Long Short-Term Memory(LSTM)findings for 2020,2021,and 2022 were observed,and anticipated values for daily rainfall during the monsoon season between July and September.According to test findings,the artificial intelligence technique cannot anticipate future regional meteorological formations;the correlation coefficient R^(2) is around 0.12.According to the randomly verified precipitation data findings,the Markov Chain model has a success rate of 79.17 percent.The results suggest that extended return periods should be a warning sign for drought and flood risk in the Himalayan region.This study gives a better knowledge of the water budget,climate change variability,and impact of global warming,ultimately leading to improved water resource management and better emergency planning to the establishment of the Early Warning System(EWS)for extreme occurrences such as cloudbursts,flash floods,landslides hazards in the complex Himalayan region. 展开更多
关键词 Forecast disasters Western Himalaya Hydro-meteorological hazards LSTM markov chain Yamuna river basin
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Synthesis, structure, and properties of Ba9Co3Se(15) with one-dimensional spin chains
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作者 Lei Duan Xian-Cheng Wang +6 位作者 Jun Zhang Jian-Fa Zhao Li-Peng Cao Wen-Min Li Run-Ze Yu Zheng Deng Chang-Qing Jin 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第3期330-334,共5页
A new compound with one-dimensional spin chains, Ba9Co3Se(15), was synthesized under high pressure and high temperature conditions and systematically characterized via structural, transport and magnetic measurements. ... A new compound with one-dimensional spin chains, Ba9Co3Se(15), was synthesized under high pressure and high temperature conditions and systematically characterized via structural, transport and magnetic measurements. Ba9Co3Se(15) crystallizes in a hexagonal structure with the space group P-6c2(No. 188) and lattice constants of a = b = 9.6765 ? and c = 18.9562 ?. The structure consists of trimeric face-sharing octahedral CoSe6 chains, which are arranged in a triangular lattice in the ab-plane and separated by Ba atoms. The distance of the nearest neighbor of CoSe6 chains is very large, given by the lattice constant a = 9.6765 ?. The Weiss temperature Tθ associated with the intra-chain coupling strength is about -346 K. However, no long-range magnetic order but a spin glass transition at ~ 3 K has been observed. Our results indicate that the spin glass behavior in Ba9Co3Se(15) mainly arises from the magnetic frustration due to the geometrically frustrated triangular lattice. 展开更多
关键词 one-dimensional chain SPIN GLASS high-pressure
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The Physical Property of Susceptibility for One-Dimensional Ferrimagnetic Chain with Alternating Spins 1 and 1/2 in Finite Magnetic Field
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作者 XIE Gang HAN Ru-Shan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第11期620-622,共3页
We further calculate the dependence of xT on T in high magnetic fields,where X denotes susceptibility and T is temperature,using our previous research work - Green function's decoupling approximate approach,for th... We further calculate the dependence of xT on T in high magnetic fields,where X denotes susceptibility and T is temperature,using our previous research work - Green function's decoupling approximate approach,for the one-dimensional ferrimagnetic chain with alternating spins 1 and 1/2.We find a linear correlation in certain range of magnetic field between the temperature of xT maximum and the magnetic field.Moreover,we simply analyze its physical meaning by our approach. 展开更多
关键词 one-dimensional spin chain susceptibility ferrimagnetic Green function
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One-dimensional Vanadyl Phosphate Containing the Tancoite-like{Ⅴ^(Ⅳ)O(HPO_4)_2}^(2–)Chain
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作者 WEN Lei HUANG Ya-Xi +6 位作者 SUN Wei LIU Biao HUANG Chun-Zuo MI Jin-Xiao ZHUANG Rong-Chuan TANG Mei-Bo ZHAO Jing-Tai 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第12期1821-1828,共8页
A vanadyl phosphate containing a new member of tancoite-like single chain, (DAPH2)[VIVO(HPO4)2]·xH20 (x ≈ 0.2, DAP = 1,3-diaminopropane, C3H10N2), has been synthesized under hydro(solvo)thermal condition... A vanadyl phosphate containing a new member of tancoite-like single chain, (DAPH2)[VIVO(HPO4)2]·xH20 (x ≈ 0.2, DAP = 1,3-diaminopropane, C3H10N2), has been synthesized under hydro(solvo)thermal conditions. It crystallizes in orthorhombic space group P21212 (No. 18) with a = 7.1730(14), b = 19.252(4), c = 8.6557(17) A, Z= 4, V= 1195.3(4)A3, C3H14.38N2P2VO9.19, Mr = 338.47, Dc = 1.881 g/cm3,μ(MoKa) = 1.138 mm-1 and F(000) = 692. The final full-matrix least-squares refinement converged to R = 0.0408, wR = 0.1046 for 2498 observed reflections with I 〉 2σ(I) and R = 0.0456 and wR = 0.1080 for all data (2750) and S = 1.001. Its one-dimensional 1 structure consists of tancoite-like ∞1 {vIVO(HPO4)2}2- single chains surrounded by DAPH22+ ions and water molecules. The single chain is built from trans-corner-sharing octahedral {VIV= O…VIV} backbone loop-branched by HPO4 groups like staple forming a new member of tancoite single chain. Due to the special coordination of VIVO6, the ∞1 {VO(HPO4)2-} chain adopts a larger M-O-M angle (V-O-V = 135°) than those of tancoite chains reported before. The corner-sharing linear {VIV = O…VIV} chain structure also leads to a one-dimensional weak antiferromagnetic interaction at low temperature. The magnetic measurements confirm the 4+ valence state of vanadium. IR and TG results of the title compound are also discussed. 展开更多
关键词 magnetic properties one-dimensional structure phosphate tancoite-like single chain VANADIUM
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Ground-State Energy and Entropy for One-Dimensional Heisenberg Chain with Alternating D-Term
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作者 Chunhuan Xiang Honglei Wang 《Journal of Applied Mathematics and Physics》 2019年第5期1220-1225,共6页
We study the ground-state information of one-dimensional Heisenberg chain with alternating D-term. Given the ground-state phase diagram, the ground-state energy and the entanglement entropy are obtained by tensor-net ... We study the ground-state information of one-dimensional Heisenberg chain with alternating D-term. Given the ground-state phase diagram, the ground-state energy and the entanglement entropy are obtained by tensor-net work algorithm. The phase transition points are shown in the entanglement entropy figure. The results are agreed with the phase diagram. 展开更多
关键词 GROUND-STATE Energy ENTROPY one-dimensional HEISENBERG chain
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One-dimensional Chain Crown Ether Complexes Synthesis and Crystal Structure of ([K(DB18-crown-6)]_(2)(CH_(3)CN))[Pt(SCN)_(4)]
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作者 LI Da-cheng LIU Ying DOU Jian-rain 《聊城大学学报(自然科学版)》 2003年第2期7-8,71,共3页
The complexe{[K(DB18-crown-6)]_(2)(CH_(3)CN)}[Pt(SCN)_(4)]was synthesized and characterized by elemental analysis,IR spectrum and X-ray diffraction analysis.The complexe belongs to monoclinic,space group c2/c with cel... The complexe{[K(DB18-crown-6)]_(2)(CH_(3)CN)}[Pt(SCN)_(4)]was synthesized and characterized by elemental analysis,IR spectrum and X-ray diffraction analysis.The complexe belongs to monoclinic,space group c2/c with cell dimensions,a=2.5904(8),6=1.3653(4),c-1.84706(6)nm,β=123.811(4)°,V=5-339(3)nm^(3),Z=4,.Dcalcd=l.577 g/cm^(3),F(000)=2552,R_(1)=0.051 l,wR_(2)=0.1411.The complexe shows one-dimensional chain of{[K(DB18-crown-6)]+complex cation and[Pt(SCN),i]2-complex anion bridged by N atom of CHaCN moleculer between two[K(DB18-crown-6)]_(2)[Pt(SCN)_(4)]groups respectively. 展开更多
关键词 one-dimensional chain Pt complex DB18-crown-6 crystal structure
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多重填补法Markov Chain Monte Carlo模型在有缺失值的妇幼卫生纵向数据中的应用 被引量:7
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作者 茅群霞 李晓松 《四川大学学报(医学版)》 CAS CSCD 北大核心 2005年第3期422-425,共4页
目的 针对妇幼卫生纵向数据的任意缺失模式,采用多重填补方法进行填补,探求最佳填补结果,以便对数据作进一步分析与研究。方法 运用SAS9.0 ,采用多重填补方法Markov China Monte Carlo(MCMC)模型对缺失数据进行多次填补并综合分析。... 目的 针对妇幼卫生纵向数据的任意缺失模式,采用多重填补方法进行填补,探求最佳填补结果,以便对数据作进一步分析与研究。方法 运用SAS9.0 ,采用多重填补方法Markov China Monte Carlo(MCMC)模型对缺失数据进行多次填补并综合分析。结果 填补5次所得结果最优。结论 多重填补方法可以处理有缺失数据资料中的许多普遍问题,可提高统计效率,尤其是MCMC模型在处理复杂的缺失数据上,优势明显。 展开更多
关键词 多重填补法 markov chain MONTE Carlo 缺失值 妇幼卫生
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基于Markov Chain的协议异常检测模型 被引量:6
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作者 李娜 秦拯 +1 位作者 张大方 陈蜀宇 《计算机科学》 CSCD 北大核心 2004年第10期66-68,95,共4页
本文介绍了基于Markov链的协议异常检测模型,此外,通过对MIT Lincoln实验室1999评估数据的分析,证明此模型的正确性和有效性。
关键词 异常检测模型 协议 正确性 数据 markov MIT 证明 实验室 有效性
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基于MLP-ANN与Markov Chain的土地利用变化预测方法——以锡林郭勒盟为例 被引量:8
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作者 徐广才 康慕谊 李亚飞 《生态环境学报》 CSCD 北大核心 2010年第10期2386-2392,共7页
以北方草地典型地区—内蒙古锡林郭勒盟为案例区,在1995年到2000年的土地利用变化与驱动力分析的基础上,利用土地利用转换类型和驱动力模型,采用多层感知人工神经网络模型分析了各种土地利用类型未来的转换潜力;利用马尔可夫链模型,预测... 以北方草地典型地区—内蒙古锡林郭勒盟为案例区,在1995年到2000年的土地利用变化与驱动力分析的基础上,利用土地利用转换类型和驱动力模型,采用多层感知人工神经网络模型分析了各种土地利用类型未来的转换潜力;利用马尔可夫链模型,预测了2005和2010年土地利用格局。预测结果显示:高覆盖度草地减少幅度最大,中覆盖度草地减少相对和缓,高、中覆盖度草地的减少造成了未利用地和低覆盖度草地的增加,尤其是前者增加的幅度最大;从空间分布看,高覆盖度草地的减少集中在西北部地区,主要转变为中低覆盖度草地,中覆盖度草地的减少主要集中在西南部地区,其流向主要是以沙化土地为主的未利用地;案例研究表明,多层感知人工神经网络模型与马尔可夫链模型的结合与应用能够在很大程度上预测稳定驱动力作用下的土地利用变化趋势,从而为生态干预提供指导。 展开更多
关键词 土地利用与覆被变化 模拟 多层感知人工神经网络模型 马尔可夫链 锡林郭勒盟
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高等院校教师人才流动的Markov-chain预测模型 被引量:2
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作者 昝欣 宗鹏 吴祈宗 《南京师范大学学报(工程技术版)》 CAS 2006年第3期75-78,共4页
介绍并解析随机过程理论中的马尔科夫过程与马尔科夫链;针对高等院校教师人才流动变化过程,利用马尔科夫过程分析方法建立描述人员流动变化趋势的Markov-chain预测模型,详细阐述了模型的算法步骤.以某所高等院校教师人才流动的状态转移... 介绍并解析随机过程理论中的马尔科夫过程与马尔科夫链;针对高等院校教师人才流动变化过程,利用马尔科夫过程分析方法建立描述人员流动变化趋势的Markov-chain预测模型,详细阐述了模型的算法步骤.以某所高等院校教师人才流动的状态转移数据作为算例,运用新建立的预测模型,对该院校教师人才的流动趋势做出了预测分析.最后,将教师进修状态纳入分析范围,进行了教师职业生涯和职务发展趋势预测的深入分析.应用模型对实际算例的求解结果表明:Markov-chain预测模型及算法,叙述简洁、运算方便,为高等院校教师人才流动,乃至其他行业人才流动的预测提供了一种新的、有效的思路和方法. 展开更多
关键词 人才流动 马尔科夫过程 马尔科夫链 markov-chain预测模型 人力资源
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基于Markov chain理论的科技成果转化的市场预测 被引量:1
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作者 徐辉 张延飞 彭萍 《东华理工学院学报》 2005年第2期196-200,共5页
科技成果成功转化的主要标志是其产品的市场畅销度。产品的畅销度由于受各种内外部不确定因素影响,具有随机不确定性。基于这种随机不确定性,运用Markovchain对其产品进行市场预测,并通过实证分析说明其有效性,为科技成果的转化提供具... 科技成果成功转化的主要标志是其产品的市场畅销度。产品的畅销度由于受各种内外部不确定因素影响,具有随机不确定性。基于这种随机不确定性,运用Markovchain对其产品进行市场预测,并通过实证分析说明其有效性,为科技成果的转化提供具体可行的定量依据。 展开更多
关键词 科技成果 markov chain 市场预测
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基于RS-SPA-Markov chain的生物质气化站安全评价与预测模型研究 被引量:2
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作者 王贝贝 孙家伟 +1 位作者 许开立 张辉 《工业安全与环保》 北大核心 2016年第2期59-62,共4页
本文在资料收集、实地考察、专家评估的基础上,建立了相对通用的生物质气化站安全评价指标体系,引入了RS-SPA-Markov chain安全评价与预测模型。通过实例应用,证明了该模型应用于生物质气化站安全评价与预测的可行性和科学性,为生物质... 本文在资料收集、实地考察、专家评估的基础上,建立了相对通用的生物质气化站安全评价指标体系,引入了RS-SPA-Markov chain安全评价与预测模型。通过实例应用,证明了该模型应用于生物质气化站安全评价与预测的可行性和科学性,为生物质气化站安全评价与预测提供了一种新的途径。 展开更多
关键词 生物质气化站 粗糙集 集对分析 马尔科夫链 安全评价与预测
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Auto-selection order of Markov chain for background sequences with chi-square test
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作者 谢雪英 孙啸 陆祖宏 《Journal of Southeast University(English Edition)》 EI CAS 2003年第4期311-316,共6页
Modeling non coding background sequences appropriately is important for the detection of regulatory elements from DNA sequences. Based on the chi square statistic test, some explanations about why to choose higher ... Modeling non coding background sequences appropriately is important for the detection of regulatory elements from DNA sequences. Based on the chi square statistic test, some explanations about why to choose higher order Markov chain model and how to automatically select the proper order are given in this paper. The chi square test is first run on synthetic data sets to show that it can efficiently find the proper order of Markov chain. Using chi square test, distinct higher order context dependences inherent in ten sets of sequences of yeast S.cerevisiae from other literature have been found. So the Markov chain with higher order would be more suitable for modeling the non coding background sequences than an independent model. 展开更多
关键词 non coding sequences regulatory elements chi square test markov chain
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Applicability of Markov chain-based stochastic model for bubbling fluidized beds
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作者 庄亚明 陈晓平 刘道银 《Journal of Southeast University(English Edition)》 EI CAS 2015年第2期249-253,共5页
A Markov chain-based stochastic model (MCM) is developed to simulate the movement of particles in a 2D bubbling fluidized bed (BFB). The state spaces are determined by the discretized physical cells of the bed, an... A Markov chain-based stochastic model (MCM) is developed to simulate the movement of particles in a 2D bubbling fluidized bed (BFB). The state spaces are determined by the discretized physical cells of the bed, and the transition probability matrix is directly calculated by the results of a discrete element method (DEM) simulation. The Markov property of the BFB is discussed by the comparison results calculated from both static and dynamic transition probability matrices. The static matrix is calculated based on the Markov chain while the dynamic matrix is calculated based on the memory property of the particle movement. Results show that the difference in the trends of particle movement between the static and dynamic matrix calculation is very small. Besides, the particle mixing curves of the MCM and DEM have the same trend and similar numerical values, and the details show the time averaged characteristic of the MCM and also expose its shortcoming in describing the instantaneous particle dynamics in the BFB. 展开更多
关键词 stochastic model markov chain discrete elementmethod (DEM) bubbling fluidized bed (BFB)
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基于Markov Chain Monte Carlo模型对医院调查资料中缺失数据的多重估算 被引量:3
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作者 李树威 钟晓妮 《中国卫生统计》 CSCD 北大核心 2013年第6期837-841,共5页
目的探讨基于Markov Chain Monte Carlo(MCMC)模型的多重估算法在处理医院调查资料缺失数据中的应用。方法运用SAS9.2编写程序,在分析数据的分布类型和缺失机制的基础上,采用MCMC法对缺失数据进行多次填补和联合统计推断,分析多重估算... 目的探讨基于Markov Chain Monte Carlo(MCMC)模型的多重估算法在处理医院调查资料缺失数据中的应用。方法运用SAS9.2编写程序,在分析数据的分布类型和缺失机制的基础上,采用MCMC法对缺失数据进行多次填补和联合统计推断,分析多重估算法的优势。结果数据服从多元正态分布与随机缺失,采用MCMC法填补10次所得的结果最佳。结论多重估算既可反映缺失数据的不确定性,又可充分利用现有资料的信息、提高统计效率、对模型的估计结果更加可信,是处理缺失数据的有效方法。 展开更多
关键词 缺失数据 markov chain MONTE Carlo 多重估算 医院调查资料
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D-S理论和Markov链组合的桥梁性能退化预测研究
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作者 杨国俊 田里 +2 位作者 唐光武 毛建博 杜永峰 《应用数学和力学》 CSCD 北大核心 2024年第4期416-428,共13页
为准确预测桥梁性能退化,考虑到数据随机性和微小扰动发生状态跳跃,提出了一种D-S(Dempster-Shafer)证据理论和Markov链组合的桥梁性能退化组合预测模型和性能退化率的概念.该模型基于指数平滑(exponential smoothing,ES)方法获得新的... 为准确预测桥梁性能退化,考虑到数据随机性和微小扰动发生状态跳跃,提出了一种D-S(Dempster-Shafer)证据理论和Markov链组合的桥梁性能退化组合预测模型和性能退化率的概念.该模型基于指数平滑(exponential smoothing,ES)方法获得新的预测数据序列,并利用Markov链和D-S理论不断进行优化,从而实现桥梁性能退化的组合预测.实际工程的应用结果表明:性能退化率可以直观地表征在梁性能退化的速度.其次,该模型的平均相对误差为1.54%,较于回归、灰色和模糊加权Markov链模型,精度分别提高了1.11%,0.88%和2.8%,而后验差比值为0.242,小于0.35;模型的标准差为9.021,相比其他模型分别减小了3.978,3.405和7.500,而变异系数为0.109,均小于其他模型,验证了组合预测模型在精度和稳定性方面的优越性,可为在役桥梁结构性能退化预测与维护提供理论基础. 展开更多
关键词 桥梁工程 性能退化预测 D-S证据理论 markov 组合预测模型 桥梁性能退化率
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Basic Lithofacies-Succession Model for the Wumishan Cyclothems: Their Markov Chain Analysis and Regularly Vertical Stacking Patterns in the Third-Order Sequences 被引量:19
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作者 MEI Mingxiang, MA Yongsheng and GUO Qingyin Institute of Earth Sciences and Natural Resources, China University of Geosciences, Beijing 100083 China Petrochemical Corporation (SINOPEC), Beijing 100029 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2001年第4期421-431,共11页
The Mesoproterozoic Wumishan Formation in the Jixian section of Tianjin is a succession of 3300-m-thick carbonate strata formed in a period of about 100 Ma (1310±20 Ma-1207±10 Ma). In this succession of stra... The Mesoproterozoic Wumishan Formation in the Jixian section of Tianjin is a succession of 3300-m-thick carbonate strata formed in a period of about 100 Ma (1310±20 Ma-1207±10 Ma). In this succession of strata, the carbonate metre-scale cyclic sequences belonging to peritidal type with an approximately symmetrical lithofacies-succession are best developed. The wide development of 1:4 stacking patterns shows that these metre-scale cyclic sequences are genetically related to the short-eccentricity cycles, which are called the Wumishan cyclothems that could truly represent sedimentary cycles. Generally, massive and thick-bedded calcareous dolomites and dolomitic limestones of stromatolite biostromes and thrombolite bioherms constitute the central part of the Wumishan cyclothems. The lower and upper parts consist of tidal flat dolostones, sandy-muddy dolostone and the top part is composed of lagoonal facies dolomitic shales with a paleosol cap. Therefore, an approximately symmetrical lithofacies-succession is formed. Many features such as the clear deepening and shoaling vectors of cyclothems, and all kinds of marks of fresh-water diagenesis indicate that the Wumishan cyclothems are the product of autocyclic sedimentation governed by allocyclic high-frequency sea-level changes. The results of a Markov chain analysis reaffirm the existence of the lithofacies-succession model of the Wumishan cyclothems. The boundaries of the Wumishan cyclothems are marked by the instantaneous exposed punctuated surface, which leads to the discrepancy between the cyclothems and the parasequences of the sequence stratigraphy terminology system. It is difficult to form a judgment that the time span of the Milankovitch cycles in the Precambrian is certainly equal to that of the Phanerozoic, but the regularly vertical stacking patterns of the seventh-order rhythms, sixth-order cyclothems and fifth-order parasequence sets still indicate their consistency with the duration of the Milankovitch cycles in the Phanerozoic. 展开更多
关键词 Wumishan cyclothems markov chain analysis MESOPROTEROZOIC Jixian section TIANJIN
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