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A New Probabilistic Transformation in Generalized Power Space

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Chinese Journal of Aeronautics 2011年第4期24卷 449-460页

作者： HU Lifang he you GUAN Xin DENG Yong HAN Deqiang Research Institute of Information Fusion Naval Aeronautical and Astronautical University Yantai 264001 China Sche Institute of Electronic Science and Engineering National University of Defense Technology Changsha 410073 China School of Electronics and Information Technology Shanghai Jiao Tong University Shanghai 200240 China Institute of Integrated Automation Xi 'an Jiaotong University Xi'an 710049 China

The mapping from the belief to the probability domain is a controversial issue, whose original purpose is to make （hard） decision, but for contrariwise to erroneous widespread idea/claim, this is not the only interest for using such mappings nowadays. Actually the probabilistic transformations of belief mass assignments are very useful in modern multitarget multisensor tracking systems where one deals with soft decisions, especially when precise belief structures are not always available due to the existence of uncertainty in human being’s subjective judgments. Therefore, a new probabilistic transformation of interval-valued belief structure is put forward in the generalized power space, in order to build a subjective probability measure from any basic belief assignment defined on any model of the frame of discernment. Several examples are given to show how the new transformation works and we compare it to the main existing transformations proposed in the literature so far. Results are provided to illustrate the rationality and efficiency of this new proposed method making the decision problem simpler.

关键词： Dempster-Shafer theory generalized power space information fusion interval value uncertainty

New conflict representation model in generalized power space

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Journal of Systems Engineering and Electronics 2012年第1期23卷 1-9页

作者： you he Lifang Hu Xin Guan Deqiang Han Yong Deng Research Institute of Information Fusion Naval Aeronautical and Astronautical University Yantai 264001 E R. China Navy Armament Academy Beijing 102249 P. R. China College of Electronic Science and Engineering National University of Defense Technology Changsha 410073 E R. China Institute of Integrated Automation Xi＇an Jiaotong University Xi＇an 710049 E R. China School of Electronics and Information Technology Shanghai Jiaotong University Shanghai 200240 E R. China

The study on alternative combination rules in Dempster- Shafer theory （DST） when evidences are in conflict has emerged again recently as an interesting topic, especially in data/information fusion applications. The earlier researches have mainly focused on investigating the alternative which would be appropriate for the conflicting situation, under the assumption that a conflict is identified. However, the current research shows that not only the combination rule but also the classical conflict coefficient in DST are not correct to determine the conflict degree between two pieces of evidences. Most existing methods of measuring conflict do not consider the open world situation, whose frame of discernment is incomplete. To solve this problem, a new conflict representa- tion model to determine the conflict degree between evidences is proposed in the generalized power space, which contains two parameters： the conflict distance and the conflict coefficient of inconsistent evidences. This paper argues that only when the con- flict measure value in the new representation model is high, it is safe to say the evidences are in conflict. Experiments illustrate the efficiency of the proposed conflict representation model.

关键词： Dezert-Smarandache theory (DSmT) conflict evidence Dempster rule of combination information fusion.

DOUBLE-PARAMETER PERTURBATION SOLUTION TO 3-D NONLINEAR PROBLEM OF OBLIQUE WATER EXIT

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Journal of Hydrodynamics 1991年第4期3卷 96-103页

作者： Qu-yuan, Ye you-sheng, he Shanghai Jiao Tong Univ Shanghai China

With a new time-derivative operator, the nonlinear kinematic and dynamic free boundary conditions were modified to a convenient form for numerical computation. The original 3-D nonlinear problem of oblique water exit of an axisymmetric body at a large water exit-angle and a small angle of attack is reduced to a number of 2-D problems by means of the double-parameter-series expansion method and the Fourier-cosine-expansion method. Numerical results are presented of the free surface shapes and the forces exerted during the oblique water exit of a sphere at different Froude numbers.

关键词： Flow of Water Mathematical Models Mathematical Techniques Nonlinear Equations Mathematical Techniques Perturbation Techniques

Research on Radar Emitter Attribute Recognition Method

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Geo-Spatial Information Science 2006年第1期9卷 45-48页

作者： GUAN Xin YI Xiao he you Naval Aeronautical Engineering Institute 188 Erma Road Yantai 264001 China

In order to solve emitter recognition problems in a practical reconnaissance environment, attribute mathematics is introduced. The basic concepts and theory of attribute set and attribute measure are described i n detail. A new attribute recognition method based on attribute measure is prese nted in this paper. Application example is given, which demonstrates this new me thod is accurate and effective. Moreover, computer simulation for recognizing th e emitter purpose is selected, and compared with classical statistical pattern r ecognition through simulation. The excellent experimental results demonstrate t hat this is a brand-new attribute recognition method as compared to existing st atistical pattern recognition techniques.

关键词： attribute measure attribute recognition criterion emitter recognition

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青海省不同生境下青海云杉胸径生长模型研究

林业科学研究 2024年第1期37卷 119-129页

作者：马浩陈科屹徐干君党禹杰何友均王建军国家林业和草原局西北调查规划院陕西西安710048 中国林业科学研究院林业科技信息研究所北京100091

[目的]研究不同生境压力下青海云杉的林木胸径生长规律及生长模型,为有效保护、合理经营青海云杉林提供经验模型。[方法]利用青海地区青海云杉的树轮数据,计算单木胸径生长量,分析不同起源、不同坡位条件下胸径生长规律,构建单木胸径生... 详细信息

[目的]研究不同生境压力下青海云杉的林木胸径生长规律及生长模型,为有效保护、合理经营青海云杉林提供经验模型。[方法]利用青海地区青海云杉的树轮数据,计算单木胸径生长量,分析不同起源、不同坡位条件下胸径生长规律,构建单木胸径生长模型,对比与评价不同模型的拟合优度结果。随后选取基础模型,建立考虑起源和坡位的青海云杉单木胸径混合效应模型,采用全部数据对模型进行检验。[结果]总体来看,青海云杉生长到胸高位置后,单木胸径生长量随着年龄的增加呈现下降后平缓变化趋势;青海云杉天然林、人工林单木生长的速生期分别为29—44 a、29—39 a,连年生长量(CAI)和平均生长量(MAI)均在0.40 cm以上,随后天然林单木CAI和MAI的变化平缓,人工林的变化幅度较大。不同坡位的单木胸径生长趋势具有差异。生长模型结果显示,不同起源、坡位条件下各树种最优胸径生长模型的决定系数(R^(2))均在0.913以上,总体相对误差(TRE)和平均系统误差(MSE)均在±2%以内,平均预估误差(MPE)大多在5%以内,平均百分标准误差(MPSE)在35%以内。以Gompertz模型为基础模型构建的混合效应模型的R^(2)为0.702,拟合效果优于基础模型;检验指标TRE为0.03%,MSE为-0.30%,MPE为4.23%,MPSE为29.54%,较基础模型分别下降89.3%、83.5%、20.6%、15.1%。[结论]不同生境条件下青海云杉的胸径生长规律具有差异,天然林的快速生长期持续时间长;所构建的单木胸径生长混合效应模型,可以用于估算青海省不同生境条件下青海云杉的林木胸径生长量变化。

关键词：胸径生长量生长规律单木生长模型混合效应模型青海

Extraction on the Contact Forces Among the Opaque and Non-photoelastic Particles Under Electromagnetic Force

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Acta Mechanica Solida Sinica 2022年第2期35卷 248-260页

作者： Shuaike Jiao Cong Liu Jun Zhou Xingyi Zhang you-he Zhou Key Laboratory of Mechanics on Disaster and Environment in Western China Attached to the Ministry of Education of China Lanzhou UniversityLanzhou 730000China Department of Mechanics and Engineering Sciences College of Civil Engineering and MechanicsLanzhou UniversityLanzhou 730000China

Contact force is related to the mechanical response of superconducting strands under a large electromagnetic body force,which is important for the safety of the international t hermonuclear experimen tai reac tor(ITER)magne t struc *** to the complex st rue ture of the cable-in-conduit conductor(CICC),the component unit of the ITER magnet,and the extreme operating environment,the research on the strand contact force caused by the electromagnetic force has been progressing *** this study,a two-dimensional(2D)theoretical model based on the granular elemen t method is construe ted to compute the contac t forces among some opaque and non-photoelastic ferromagnetic particles which are placed in a non-uniform magnetic *** the experiment,the contact deformations of these particles may be obtained by the digital image correlation *** also propose a method,which is similar to the least-squares method,to calculate the electromagnetic body forces of different ***,the distributional and statistical characteristics of the contac t force chains and contact angles are presen *** is considered that the method proposed in this paper is suitable for the contact force analysis of the cross section of superconducting strands in the ITER CICC that is subjected to a transverse elec-tromagnetic *** the end,this 2D theoretical model is generalized to the three-dimensional(3D)case,and the concise mathematical framework is presented.

关键词： Contact force Electromagnetic force Superconducting strand Cross section

First-principles Study of NiAl Alloyed with Rare Earth Element Ce

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Journal of Materials Science & Technology 2011年第8期27卷 719-724页

作者： you Wang Junqi he Mufu Yan Chonggui Li Liang Wang YeZhou Department of Materials Science School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China

The structural, elastic, and electronic properties of NiAI alloyed with rare earth element （REE） Ce have been investigated by using density functional theory （DFT）. It is found that Ce has a strong AI site preference and causes lattice distortion of NiAI. The calculation of elastic constants shows that Ce increased both the hardness and the ductility of NiAI, which could be explained by the formation of new ionic bonds between AI （and Ni） and Ce and the enhancement of covalent bonds in NisAl7Ce. Our results are in good agreement with the available experimental data and other theoretical results.

关键词： Point defects Electronic states First-principles

Shale gas production evaluation framework based on data-driven models

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Petroleum Science 2023年第3期20卷 1659-1675页

作者： you-Wei he Zhi-Yue he Yong Tang Ying-Jie Xu Ji-Chang Long Kamy Sepehrnoori State Key Laboratoryofiland Gas Rseroir Geoogy and Exloitation Southwest Petroleum UniverstyChengdu00SichuanChina Department of Petroleum and Geosystems Engineering The University of Texas at AustinAustinTX78712UA

Increasing the production and utilization of shale gas is of great significance for building a clean and low-carbon energy *** decline of gas production has been widely observed in shale gas *** to forecast shale gas production is still challenging due to complex fracture networks,dynamic fracture properties,frac hits,complicated multiphase flow,and multi-scale flow as well as data quality and *** work develops an integrated framework for evaluating shale gas well production based on data-driven ***,a comprehensive dominated-factor system has been established,including geological,drilling,fracturing,and production *** processing and visualization are required to ensure data quality and determine final data set.A shale gas production evaluation model is developed to evaluate shale gas production ***,the random forest algorithm is used to forecast shale gas *** prediction accuracy of shale gas production level is higher than 95%based on the shale gas reservoirs in ***-one wells are randomly selected to predict cumulative gas production using the optimal regression *** proposed shale gas production evaluation frame-work overcomes too many assumptions of analytical or semi-analytical models and avoids huge computation cost and poor generalization for numerical modelling.

关键词： Shale gas Production evaluation Production prediction Data-driven models Carbon neutrality

Bifurcation of a Swelling Gel with a Mechanical Load and Geometric Constraint

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Chinese Physics Letters 2011年第11期28卷 253-256页

作者： XUE Feng YONG Hua-Dong ZHOU you-he Key Laboratory of Mechanics on Disaster and Environment in Western China(Ministry of Education of China) and Department of MechanicsLanzhou UniversityLanzhou 730000

We present an analysis of the bifurcation phenomenon of a gel in contact with a *** a Mooney–Rivlin form-free energy function is introduced,an asymmetric swelling may appear for a gel swelling under uniaxial constraint or subjected to equal dead loads,which results in an interesting pitchfork bifurcation *** present an analytical investigation of this problem based on the classical theory of continuum *** bifurcation points are obtained for different values of the chemical potential of the solvent *** results demonstrate that the free swelling of the gel under uniaxial constraint will not result in the bifurcation unless further mechanical loads are applied.

关键词： bifurcation swelling constraint