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Simulation of dike-break processes in the Yellow River

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Science China(Technological Sciences) 2002年第6期45卷 606-619页

作者：梁林倪晋仁 A.G.L.Borthwick B.D.Rogers Department of Environmental Engineering Peking University Beijing 100871 China The Key Laboratory of Water and Sediment Sciences Ministry of Education Beijing 100871 China

Although dike-break and dam-break processes have similar unsteady and discontinuous hydrodynamic characteristics, there are significant differences. In general, dam-break simulations focus on the flood discharge, whereas dike-break simulations are required to provide detailed information on the hydraulic and breach evolution processes, such as pit-scour and breach-expansion. In order to overcome the difficulties inherent in applying existing dam-break models to dike-breaks, this paper presents an integrated model that combines the shallow water, sediment transport, riverbed deformation and breach-expansion equations. A Godunov-type finite volume method is used for the flow simulation, based on a fixed quadtree grid system. The hydrodynamic aspects of the model are validated for an idealized rectangular dam break. A representative reach in the Yellow River is selected at a location where there is a significant risk of a dike-break, and full-scale topographic and hydrologic data are available. Typical dike-break processes are successfully simulated, with predicted hydraulic characteristics and terrain changes qualitatively in agreement with laboratory data. The modeling study is of practical importance for implementation of engineering countermeasures in the Yellow River, such as breach blocking and head wrapping.

关键词： Yellow River dike-break shallow water Godunov finite volume breach

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改革的转型与突破口选择

A STUDY ON THRESHOLDS IN THE CHANGE OF ALLUVIAL FAN AND DELTA OF THE HUANGHE RIVER, CHINA

社会主义经济理论与实践 2005年第8期 21-26页

作者：张馨

我国改革已进入攻坚阶段。加快改革转型，进行政治体制改革是关键。要以政府预算制度改革为突破口，推动改革转型取得突破性进展。

关键词：改革体制转型政府预算制度突破口 reform regime transition government budget system breach

来源：人大复印报刊资料评论

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Chinese Geographical Science 1991年第3期1卷 68-77页

作者：曹银真 1. Institute of Geography Academic Sinica 100101 Beijing PRC

In the river systems, the environmental change always undergoes a process from quantitative to qualitative change. The upper limit of the qualitative change is called threshold. When the process reaches or goes beyond the limit, the original event series will be replaced by the other event series. Investigations show that the evolution of the Huanghe River alluvial fan and delta has also under gone a process from quantitative to qualitative change. The geometric forms in each process are roughly the same. This threshold of the geometric forms not only provides us a quantitative index for plotting the periodicity of the alluvial fan and delta, but also is of importance for estimation of the trend of natural environmental *** is shown that there are three periodic alluvial fans of the Huanghe River since the middle Holocene and four periodic delta since 1855 A.D., the thresholds of their geometric forms are from 0.93 to 0.94 and from 1.2 to 1.21 *** changing trend in the past and the

关键词： alluvial fan Huanghe River delta thresholds breach and Changing Course

维普期刊数据库

Analytical Methods in the Quality Control of Scientific Publications Part III: Publishers’ Ethics and Editors’ Complicity

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International Journal of Analytical Mass Spectrometry and Chromatography 2014年第3期2卷 77-102页

作者： Ilia Brondz Norwegian Drug Control and Drug Discovery Institute (NDCDDI) AS Ski Norway

In 2012, the first paper in the series Analytical Methods in Quality Control of Scientific Publications was published in the American Journal of Analytical Chemistry, Vol. 3, No. 6, 2012, pp. 443-447. This paper was mainly based on evidence presented in the 2011 in book Historical Overview of Chromatography and Related Techniques in Analysis of Antimalarial Drug Primaquine (editor Ilia Brondz, Nova Science Publishers, Inc., ISSN 978-1-61761-944-1). The first paper in this series di- scussed issues of obvious falsification and plagiarism contained in paper published by Dongre et al., Applications of GC-EI-MS for the Identification and Investigation of Positional Isomer in Primaquine, an Antimalarial Drug. Journal of Pharmaceutical and Biomedical Analysis, Vol. 39, No. 1-2, 2005, pp. 111-116. Dongre et al. copied their publication from an original research manuscript submitted for consideration by other authors. This paper was published in the Asian Journal of Chemistry, Vol. 17, No. 3, 2005, pp. 1678-1688. Conclusive arguments against the publication of Dongre et al. were presented in the American Journal of Analytical Chemistry, Vol. 3, No. 6, 2012, pp. 443-447. Further cases of general plagiarism and incompetence relating to authors, reviewers, editors, and publishers were presented in Part II in Analytical Methods in Quality Control of Scientific Publications Part II: The Authors’, Reviewers’, Editors’ Responsibility and the Publishers’ Authority in the International Journal of Analytical Mass Spectrometry and Chromatography, Vol. 1, No. 2, 2013, pp. 81-89. The present paper will discuss the following issues: the obvious neglect of the rights of authors by some publishers and editors;how original research manuscripts are exposed to mediocre researchers, and possibly sold, by editors to these “scientists” to boost the image of these particular “scientists”;how the order of authors’ names in published articles are changed to satisfy the commercial interests of compa

关键词： Publishers’ Ethics Editors’ Complicity breach of Copyright Plagiarism Falsification Fraud Chromatography Mass Spectrometry

The Whaling in the Antarctic Case, Applying the International Convention for the Regulation of Whaling as a Self-contained Regime

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中国海洋法学评论（中英文版） 2017年第2期 75-108页

作者： Lilian del Castillo University of Buenos Aires School of Law

The Whaling in the Antarctic Case (Australia v. Japan: New Zealand intervening) decided by the International Court of Justice (hereinafter "ICJ" or "the Court") on 31 March 2014 dealt with the interpretation of specific provisions of the 1946 International Convention for the Regulation of Whaling (ICRW), in particular Article VIII.1, and its complementary instruments, i.e., the Schedule and the Annexes of the International Whaling Commission Scientific Committee. The decision of the Court was a remarkable good one. However, its rigorous reasoning focused almost exclusively on the required purpose of "scientific research" of the JARPA II Programme1 permits as set out in the ICRW, approaching the convention as an autonomous self-contained regime which leaves aside other additional grounds. Nonetheless, it would be beneficial for further jurisdictional developments to strengthen the scope of the ICWR system with the applicable provisions of the United Nations Convention on the Law of the Sea (UNCLOS) and other treaties and institutions impinging on whales and whaling, e.g., CITES, Bonn Convention, Antarctic Treaty System, among others. The query remains concerning the unexplored sources of international law ruling Antarctic spaces and species which are absent in the judgment of the Court but may allow an evolutive interpretation of the ICRW.

关键词： Article VIII (ICRW) “Purpose of scientific research” Whaling moratorium UNCLOS Good faith Abuse of rights Japan’s breach of obligations

Protection Model of Security Systems Based on Neyman-Person Criterion

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Communications and Network 2013年第3期5卷 578-583页

作者： Haitao Lv Ruimin Hu Jun Chen Zheng He National Engineering Research Center for Multimedia Software Wuhan University Wuhan China

In this paper security systems deployed over an area are regarded abstractly as a diagram of security network. We propose the Neyman-Pearson protection model for security systems, which can be used to determine the protection probability of a security system and find the weakest breach path of a security network. We present the weakest breach path problem formulation, which is defined by the breach protection probability of an unauthorized target passing through a guard field, and provide a solution for this problem by using the Dijkstra’s shortest path algorithm. Finally we study the variation of the breach protection probability with the change of the parameters of the model.

关键词： Security System Protection Probability Security Network breach Protection Probability breach Path

OVERVIEW OF DAM GULLY EROSION RESEARCH

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International Journal of Sediment Research 2005年第3期20卷 105-115页

作者： G. J. HANSON,D. M. TEMPLE,K. M. ROBINSON,K. R. COOK USDA-ARS HERU Stillwater USDA-ARS HERU Stillwater USDA-NRCS ENTSC Greensboro USDA-NRCS State Office Stillwater

Traditionally gully erosion has been identified with the dissection of the landscape in agricultural settings but it is also recognized as a prevalent erosion feature in earthen dam auxiliary spillways and embankments. Flows through earthen spillways and over dam embankments, due to large rainfall events, have the potential to erode and breach the dam or spillway and result in catastrophic releases from the reservoir. The gully erosion process in an earthen spillway or on an embankment can be characterized by stages of initiation, development, and migration of a headcut. A headcut is defined as a near vertical drop at the upstream end of a gully. The rate of headcut migration is important in determining the breach potential of an earthen spillway and dam embankment. A research program is being conducted to examine the gully erosion processes of earthen dam auxiliary spillways and embankments. This paper describes: 1) the unique test facilities constructed to examine the dominant factors affecting the erosion of earthen spillways and embankments; 2) the observations of the erosion processes and results to date; and 3) the predictive relationships that have been developed for dam gully erosion research at the ARS Hydraulic Engineering Research Unit laboratory in Stillwater, OK.

关键词： Dams Erosion Spillways Embankments Gullies Headcut breach

Empirical Study on Influence of Brand Crisis of Agricultural Products on Network Cluster Behavior of Consumers

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Asian Agricultural Research 2016年第6期8卷 1-4,8页

作者： Chong GONG College of Economics and Management Huazhong Agricultural University

From the perspective of psychological contract,this paper discusses mechanism of consumers' network cluster behavior in the context of brand crisis. On the basis of Simmel's conflict theory,it presented new findings of network cluster behavior. It is concluded that brand crisis exerts significant influence on breach of psychological contract. Particularly,functional brand crisis more easily leads to breach of transactional psychological contract,while value brand crisis more easily leads to breach of relational psychological contract. breach of transactional psychological contract more easily leads to realistic network cluster behavior,while breach of relational psychological contract does not necessarily lead to non-realistic network cluster behavior.

关键词： Brand crisis Network cluster behavior breach of psychological contract

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控制系统设计中的形式化验证方法应用研究

控制系统设计中的形式化验证方法应用研究

作者：卢美洁华南理工大学

学位级别：硕士

对于一类欠驱动、强耦合的非线性混合系统,传统控制系统设计和分析方法在面对不同控制需求或系统参数变化时,往往会因参数不确定性、参数大范围变化和多参数耦合而导致系统不稳定或优化问题无解。形式化验证是一种基于数学逻辑方法的验... 详细信息

对于一类欠驱动、强耦合的非线性混合系统,传统控制系统设计和分析方法在面对不同控制需求或系统参数变化时,往往会因参数不确定性、参数大范围变化和多参数耦合而导致系统不稳定或优化问题无解。形式化验证是一种基于数学逻辑方法的验证技术,具有严谨性、全面性和可重复性的特点,通过对控制系统的形式化验证可以全面验证系统在不同情况下的行为,从而提高系统可靠性,降低开发成本和风险,帮助研究人员更好地掌控系统行为与界限。因此,本文设计了一套针对该类混合系统的控制系统设计与形式化验证框架,以带障碍物约束的直线倒立摆为研究对象,基于形式化验证工具breach进行倒立摆越障控制系统的设计及形式化验证,确定影响系统行为的关键参数安全范围及闭环系统性能边界。主要研究内容如下:(1)阐述形式化方法的基本思想和组成,包括常用形式化模型、形式规约语言和定理证明、模型检测形式化验证方法,通过对比分析几种典型验证工具的原理和适用场景,选定信号时序逻辑(Signal Temporal Logic,STL)作为形式规约语言,breach作为验证工具平台,并讨论混合系统的形式化模型和形式化验证方法,工具breach中基于采样和参数灵敏度的可达性分析原理,以及如何使用基于可达性分析的形式化验证方法求解混合系统中的参数综合问题。(2)构建带障碍物约束的直线倒立摆控制场景,对倒立摆越障控制问题进行任务分解,设计倒立摆自起摆避障切换控制系统及倒立摆稳摆越障切换控制系统,结合切换条件建立两种切换系统的混合模型,通过Simulink仿真实验界定影响系统行为安全的主要因素,并建立关于初始状态的参数综合问题和控制系统的性能边界问题,为倒立摆系统的形式化验证提供完整的控制系统混合模型及求解对象。(3)针对倒立摆越障控制目标,使用STL及其拓展语言描述系统的需求规约,并对规约进行完备性和有效性检测,结合工具breach,使用形式化验证方法求解自起摆避障控制系统中关于初始状态的参数综合问题,以及稳摆越障控制系统的性能边界,最终形成一套针对混合系统的控制系统设计与形式化验证框架,并通过实物实验说明形式化验证结果的准确性。

关键词：直线倒立摆控制形式化验证 breach 参数综合