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Ornstein-Uhlenbeck过程参数估计的渐近正态性

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湘潭大学自然科学学报 2006年第4期28卷 4-6页

作者：周占功嘉兴学院统计系浙江嘉兴314001

利用Wick引理研究并得到了OU过程的非负参数估计的渐近正态性.

关键词： OU过程 Wick引理参数估计渐近正态性

半参数变系数部分线性度量误差模型参数的经验似然比检验

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嘉兴学院学报 2012年第6期24卷 13-16,53页

作者：周占功嘉兴学院数理与信息工程学院浙江嘉兴314001

研究了半参数变系数部分线性度量误差模型参数分量的检验,基于经验似然方法,提出了对数似然比检验统计量.在零假设下,证明了检验统计量具有标准的渐近χ2分布.

关键词：变系数模型度量误差经验似然 Wilk定理

带有误差线性协变量的半参数变系数部分线性模型的协变量选择(英文)

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湘潭大学自然科学学报 2009年第4期31卷 1-6,13页

作者：周占功姜荣钱伟民同济大学数学系上海200092 嘉兴学院统计系浙江嘉兴314001

考虑了一些协变量不被观察到,但辅助变量可用时的半参数变系数部分线性模型.提出了基于SCAD惩罚的参数分量的变量选择方法,且估计既有渐近正态性又有先知性.模拟研究说明了所提出变量选择方法的有限样本性质.

关键词：辅助变量局部线性方法变系数模型误差变量 SCAD

Cox-Ingersoll-Ross模型的统计推断

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嘉兴学院学报 2006年第z1期18卷 188-192,235页

作者：舒丽玲周占功嘉兴学院数学与信息科学学院浙江嘉兴314001

该文在离散样本观察下,研究了Cox-Ingersoll-Ross模型的统计推问题,给出了CIR过程的平稳均值m与平稳方差υ的矩估计,并用m和υ给出了CIR过程中尺度参数α与β波动率之间的关系,基于CIR过程的平方变差,得到参数β的平方变差估计和参数α... 详细信息

该文在离散样本观察下,研究了Cox-Ingersoll-Ross模型的统计推问题,给出了CIR过程的平稳均值m与平稳方差υ的矩估计,并用m和υ给出了CIR过程中尺度参数α与β波动率之间的关系,基于CIR过程的平方变差,得到参数β的平方变差估计和参数α的估计。通过数值模拟的方法对平方变差估计与条件矩估计([9])方法作了比较,并选择1997-2006年的R007数据对这两种方法进行了实证分析。

关键词： Cox-Ingersoll-Ross模型平方变差估计条件矩估计

Intelligent test case generation based on branch and bound

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The Journal of China Universities of Posts and Telecommunications 2014年第2期21卷 91-97,103页

作者： XING Ying gong Yun-zhan WANG Ya-wen zhanG Xu-zhou State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications School of Electronic and Information Engineering Liaoning Technical University State Key Laboratory of Computer Architecture Institute of Computing Technology Chinese Academy of Sciences

Path-oriented test case generation is in essence a constraint satisfaction problem （CSP） solved by search strategies, among which backtracking algorithms are widely used. In this article, the backtracking algorithm branch and bound （BB） is introduced to generate path-oriented test cases automatically. A model based on state space search is proposed to construct the search tree dynamically. The BB is optimized from two perspectives. Variable permutation with a heuristic rule to break ties is adopted for the branching operation, and interval computation with analysis on the monotony of branching conditions is utilized for the bounding operation. Empirical experiments show that the proposed method performs well with linear complexity, and reaches 100% coverage on some benchmark programs with an advantage over some static and dynamic algorithms.

关键词： test case generation constraint satisfaction problem branch and bound state space search

LuoJiaAI:A cloud-based artificial intelligence platform for remote sensing image interpretation

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Geo-Spatial Information Science 2023年第2期26卷 218-241页

作者： zhan zhang Mi zhang Jianya gong Xiangyun Hu Hanjiang Xiong Huan zhou Zhipeng Cao State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhanChina School of Remote Sensing and Information Engineering Wuhan UniversityWuhanChina Department of Land-Surveying and Geo-Informatics Hong Kong Polytechnic UniversityHong KongChina

The rapid processing,analysis,and mining of remote-sensing big data based on intelligent interpretation technology using remote-sensing cloud computing platforms(RS-CCPs)have recently become a new *** existing RS-CCPs mainly focus on developing and optimizing high-performance data storage and intelligent computing for common visual representation,which ignores remote sensing data characteristics such as large image size,large-scale change,multiple data channels,and geographic knowledge embedding,thus impairing computational efficiency and *** construct a LuoJiaAI platform composed of a standard large-scale sample database(LuoJiaSET)and a dedicated deep learning framework(LuoJiaNET)to achieve state-of-the-art performance on five typical remote sensing interpretation tasks,including scene classification,object detection,land-use classification,change detection,and multi-view 3D *** details of the LuoJiaAI application experiment can be found at the white paper for LuoJiaAI industrial *** addition,LuoJiaAI is an open-source RS-CCP that supports the latest Open Geospatial Consortium(OGC)standards for better developing and sharing Earth Artificial Intelligence(AI)algorithms and products on benchmark *** narrows the gap between the sample database and deep learning frameworks through a user-friendly data-framework collaboration mechanism,showing great potential in high-precision remote sensing mapping applications.

关键词： Artificial intelligence cloud computing platform remote-sensing intelligent interpretation sample database deep learning framework

Automated String Constraints Solving for Programs Containing String Manipulation Functions

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Journal of Computer Science & Technology 2017年第6期32卷 1125-1135页

作者： Xu-zhou zhang Yun-zhan gong Ya-Wen Wang Ying Xing Ming-Zhe zhang State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China Automation School Beijing University of Posts and Telecommunications Beijing 100876 China

The ability to solve various constraints is a principal factor of automatic constraint solvers. Most object-oriented languages treat a character string as a primitive data type which is manipulated by string library functions. Most constraint solvers have limitations on their input constraints, such as strong restrictions on the expressiveness of constraints or lack of the ability to solve hybrid constraints. These limitations hinder applying automated constraint solvers on program analysis techniques for programs containing strings and string manipulation functions. We propose an approach to automatically solve program constraints involving strings and string manipulation functions. Based on the character array model, we design a constraint language which contains primitive operations to precisely describe the constraints of commonly used string manipulation functions. The translated string constraints together with numeric constraints are then solved by a two- phase test generation procedure： firstly, a partial solution is obtained to satisfy the arithmetic constraints of the position variables, and the solution is utilized to simplify the string constraints into pure character array constraints; secondly, the pure array constraints are solved by an off-the-shelf array-specific theory based constraint solver. We integrate the approach into an automated testing tool to support the generation of string test cases, and then perform experiments. The results of the experiments prove that the integration of the proposed approach promotes the testing coverage of the existing testing tool, and the integrated tool has an advantage of handling specific string manipulation functions compared with an existing string solver.

关键词： string constraints solving satisfaction module theory program analysis software testing automated testinput generation

冻融环境下玄武岩纤维增强泡沫混凝土的单轴压缩特性

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三峡大学学报（自然科学版） 2025年第1期47卷 1-8页

作者：吕国旭陈波周程涛詹明强河海大学水利水电学院南京210098 河海大学水灾害防御全国重点实验室南京210098 福建水口发电集团有限公司福州350001

为了研究密度、纤维掺量及冻融循环对玄武岩纤维增强泡沫混凝土单轴压缩特性的影响,借助X-CT技术以及Avizo软件对试件的孔隙构造进行了研究,对不同冻融环境下的多种密度等级(800和1000kg/m3)及纤维体积掺量(0%、0.15%、0.30%、0.45%)的... 详细信息

为了研究密度、纤维掺量及冻融循环对玄武岩纤维增强泡沫混凝土单轴压缩特性的影响,借助X-CT技术以及Avizo软件对试件的孔隙构造进行了研究,对不同冻融环境下的多种密度等级(800和1000kg/m3)及纤维体积掺量(0%、0.15%、0.30%、0.45%)的玄武岩纤维增强泡沫混凝土进行了单轴压缩试验,分析了不同影响因素下玄武岩纤维增强泡沫混凝土的单轴压缩特性,对各因素与抗压强度的关系进行了灰关联度分析,并使用机器学习算法模型对抗压强度进行预测.结果表明:掺入玄武岩纤维能有效提高泡沫混凝土抵抗冻融的能力,体积掺入0.15%、0.30%、0.45%的试件冻融80次后强度损失率分别为75.2%、46.2%、37.8%.密度等级与抗压强度关联度最大,灰关联度为0.799;其次是纤维掺量,关联系数为0.723;灰狼算法优化下的长短期记忆网络模型对玄武岩纤维增强泡沫混凝土抗压强度的预测性能良好.

关键词：玄武岩纤维增强泡沫混凝土单轴压缩冻融循环 X-CT 灰关联度长短期记忆网络灰狼优化算法

Sequential Fair Stackelberg Equilibria of Linear Strategies in Risk-Seeking Insider Trading

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Journal of Systems Science & Complexity 2018年第5期31卷 1302-1328页

作者： gong Fuzhou zhou Yonghui Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China Guizhou Normal University Guizhou 550001 China

This paper develops a sequential fair Stackelberg auction model in which each of the two risk-seeking insiders has an equal chance to be a leader or follower at each auction stage. The authors establish the existence, uniqueness of sequential fair Stackelberg equilibria （in short, FSE） when both insiders adopt linear strategies, and find that at the sequential equilibria such two insiders compete aggressively that cause the liquidity of market to drop, the information to be revealed and the profit to go down very rapidly while the trading intensity goes substantially high. Furthermore, the authors also give continuous versions of corresponding parameters in the sequential FSE in closed forms, as the time interval between auctions approaches to zero. It shows that such parameters go down or up approximately exponentially and all of the liquidity of market, information and profit become zero while the trading intensity goes to infinity. Some numerical simulations about the sequential FSE are also illustrated.

关键词： Continuous version insider trading risk-seeking sequential fair Stackelberg equilibria