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一种基于风险代码抽取的控制流保护方法

计算机学报 2024年第6期47卷 1372-1392页

作者：李勇钢钟叶青郑伊健林果园鲍宇中国矿业大学计算机学院信息安全系江苏徐州221116 香港中文大学(深圳)数据科学学院广东深圳518172

代码复用攻击是控制流安全面临的主要威胁之一.虽然地址分布随机化能够缓解该攻击,但它们很容易被代码探测技术绕过.相比之下,控制流完整性方法具有更好的保护效果.但是,现有的方法要么依赖于源码分析,要么采用无差别跟踪的方式追踪所... 详细信息

代码复用攻击是控制流安全面临的主要威胁之一.虽然地址分布随机化能够缓解该攻击,但它们很容易被代码探测技术绕过.相比之下,控制流完整性方法具有更好的保护效果.但是,现有的方法要么依赖于源码分析,要么采用无差别跟踪的方式追踪所有的控制流转移.前者无法摆脱对源码的依赖性,后者则会引入巨大的运行时开销.针对上述问题,本文提出一种新的控制流保护方法MCE(Micro Code Extraction).MCE的保护目标是源码不可用的闭源对象.与现有的方法相比,MCE并不会盲目地追踪所有的控制流转移活动.它实时地检测代码探测活动,并仅将被探测的代码作为保护目标.之后,MCE抽取具有潜在风险的代码片段,以进一步缩小目标对象的大小.最后,所有跳转到风险代码中的控制流都会被追踪和检测,以保护它的合法性.实验和分析表明,MCE对代码探测和代码复用攻击具有良好的保护效果,并在一般场景下仅对CPU引入2%的开销.

关键词：代码探测代码复用攻击控制流劫持代码抽取内存访问控制

A novel method of supporting gold nanoparticles on MWCNTs: Synchrotron X-ray reduction

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China Particuology 2007年第3期5卷 237-241页

作者： Kuan-Nan Lin Tsung-yeh Yang hong-Ming Lin Yeu-Kuang Hwu She-Huang Wu Chung-Kwei Lin Department of Materials Engineering Tatung University Taipei 104 Taiwan China Institute of Physics Academia Sinica 128 Academia Road Nankang Taipei 115 Taiwan China Department of Materials Science and Engineering Feng Chia University 407 Taichung Taiwan China

Gold nanoparticles decorating the surface of multiwalled carbon nanotubes （MWCNTs） are prepared by photochemical reduction. The gold clusters form different interesting geometrical faceted shapes in accordance to time duration of synchrotron X-ray irradiation. The shape of nanogold could be spherical, rod-like, or triangular. Carbon nanotubes serve as optimal templates for the heterogeneous nucleation of gold nanocrystals. These nanocrystal structures are characterized by transmission electron microscope （TEM） and element analysis by energy dispersive spectroscopy （EDS）. 2007 Chinese Society of Particuology and Institute of Process Engineering,Chinese Academy of Sciences. Published by Elsevier B.V.

关键词： Gold MWCNT Heterogeneous nucleation Synchrotron X-ray irradiation

On the number of matchings of graphs formed by a graph operation

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Science China Mathematics 2006年第10期49卷 1383-1391页

作者： yeh Yeong-Nan Institute of Mathematics Academia Sinica

Let G be a simple graph. Define R(G) to be the graph obtained from G by adding a new vertex e* corresponding to each edge e = (a, b) of G and by joining each new vertex e* to the end vertices a and b of the edge e corresponding to it. In this paper, we prove that the number of matchings of R(G) is completely determined by the degree sequence of vertices of G.

关键词： matching, Hosoya index, matching polynomial, oriented incident matrix,skew adjacency matrix.

Knowledge discovery for geographical cellular automata

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Science China Earth Sciences 2005年第10期48卷 1758-1767页

作者： Anthony Gar-On yeh Centre of Urban Planning and Environmental Management The University of Hong Kong Hong Kong SAR China

This paper proposes a new method for geographical simulation by applying data mining techniques to cellular automata. CA has strong capabilities in simulating complex systems. The core of CA is how to define transition rules. There are no good methods for defining these transition rules. They are usually defined by using heuristic methods and thus subject to uncer-tainties. Mathematical equations are used to represent transition rules implicitly and have limita-tions in capturing complex relationships. This paper demonstrates that the explicit transition rules of CA can be automatically reconstructed through the rule induction procedure of data mining. The proposed method can reduce the influences of individual knowledge and preferences in de-fining transition rules and generate more reliable simulation results. It can efficiently discover knowledge from a vast volume of spatial data.

关键词： knowledge discovery, cellular automata, geographical simulation, geographical information systems.

Multi-agent systems for simulating spatial decision behaviors and land-use dynamics

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Science China Earth Sciences 2006年第11期49卷 1184-1194页

作者： Anthony Gar-On yeh Center of Urban Planning and Environmental Management The University of Hong Kong Hong Kong SAR China

A new method to simulate urban land-use dynamics is proposed based on multi-agent systems (MAS). The model consists of a series of environmental layers and multi-agent layers, which can interact with each other. It attempts to explore the interactions between different players or agents, such as residents, property developers, and governments, and between these players and the envi- ronment. These interactions can give rise to urban macro-spatial patterns. This model is used to simulate the land-use dynamics of the Haizhu district of Guangzhou City in 1995―2004. Cellular automata (CA) were also used for the simulation of land use changes as a comparison. The study indicates that MAS has better performance for simulating complex cities than CA.

关键词： multi-agent systems, cellular automata, complex systems, cities, land use.

输尿管良性狭窄内切开前行球囊扩张的临床研究

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中华外科杂志 2008年第9期46卷 685-687页

作者：张勇 TAN yeh hong 首都医科大学附属北京朝阳医院泌尿科 100020 Department of Urology Singapore General Hospital

目的探讨输尿管良性狭窄内切开前使用球囊扩张的必要性。方法16例输尿管良性狭窄患者行钬激光输尿管内切开前6例采用球囊扩张狭窄段，10例采用输尿管硬镜扩张狭窄段。回顾性分析其临床资料和随访结果，包括病因、狭窄部位、诊断方法和... 详细信息

目的探讨输尿管良性狭窄内切开前使用球囊扩张的必要性。方法16例输尿管良性狭窄患者行钬激光输尿管内切开前6例采用球囊扩张狭窄段，10例采用输尿管硬镜扩张狭窄段。回顾性分析其临床资料和随访结果，包括病因、狭窄部位、诊断方法和超声等。结果狭窄长度为0．8—1．4cm。输尿管硬镜扩张者3例失败，改用球囊扩张成功；使用球囊扩张的患者均扩张成功。用球囊扩张的手术时间短于用输尿管硬镜扩张，但手术费用高于用输尿管硬镜扩张，差异均有统计学意义（P〈0．05）。随访3—28个月，无围手术期并发症，2例用输尿管硬镜扩张患者出现再狭窄。结论输尿管良性狭窄内切开前使用球囊扩张安全、有效，再根据患者情况适当应用。

关键词：尿道狭窄气囊扩张术钬激光内切开

A concise review about fracture assessments of brittle solids with V-notches

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Frontiers of Structural and Civil Engineering 2019年第2期13卷 478-485页

作者： Hsien-Yang yeh Bin YANG Department of Mechanical and Aerospace Engineering California State UniversityLong BeachCA 90801USA Department of Chemical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

A concise review of recent studies about the fracture assessments of elastic brittle solid materials containing V-notches is presented. In this preliminary and brief survey, elastic stress distributions in V-notched solids are discussed first. The concept of notch stress intensity factor is introduced. Combine the digital image correlation method with numerical computation techniques to analyze the stress distribution near the notches. Fracture criteria such as strain energy density, J-integral, theory of critical distance are used. However, various new materials are developed in different engineering fields, thus, the establishment of reliable and accurate material strength theory or failure criterion is imperative. Therefore, predicting fracture for various modem materials would require more experiments to infer material dependent parameters in the local fracture model.

关键词： fracture assessment brittle solids V-notches review

Microbial diversity of soil bacteria in agricultural field contaminated with heavy metals

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Journal of Environmental Sciences 2008年第3期20卷 359-363页

作者： CHIEN Chihching KUO Yumei CHEN Changchieh HUNG Chunwei yeh Chihwei yeh Weijen Graduate School of Biotechnology and Bioengineering Yuan Ze University Chung-Li Taiwan 320 China Department of Occupational Safety and Health Chung Hwa University of Medical Technology Tainan Taiwan China

In this study we evaluated the bacterial diversity in a soil sample from a site next to a chemical industrial factory previously contaminated with heavy metals. Analysis of 16S rDNA sequences amplified from DNA directly extracted from the soil revealed 17 different bacterial types （genera and/or species）. They included Polyangium spp., Sphingomonas spp., Variovorax spp., Hafina spp., Clostridia, Acidobacteria, the enterics and some uncultured strains. Microbes able to tolerate high concentrations of cadmium （500μmol/L and above） were also isolated from the soil. These isolates included strains of Acinetobacter （strain CD06）, Enterobacter sp. （strains CD01, CD03, CD04 and CD08）（similar strains also identified in culture-independent approach） and a strain of Stenotrophomonas sp. The results indicated that the species identified from direct analysis of 16S rDNA of the soil can be quite different from those strains obtained from enrichment cultures and the microbial activities for heavy metal resistance might be more appropriately addressed by the actual isolates.

关键词： cadmium heavy metal heavy metal resistant microbial diversity soil bacteria

Biomimetic flexible plate actuators are faster and more efficient with a passive attachment

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Acta Mechanica Sinica 2016年第6期32卷 1001-1011页

作者： Peter D.yeh Alexander Alexeev George W.Woodruff School of Mechanical Engineering Georgia Institute of Technology

Using three-dimensional computer simulations, we probe biomimetic free swimming of an internally actuated flexible plate in the regime near the first natural frequency. The plate is driven by an oscillating internal moment approximating the actuation mechanism of a piezoelectric macro fiber composite (MFC) bimorph. We show in our simulations that the addition of a passive attachment increases both swimming velocity and efficiency. Specifically, if the active and passive sections are of similar size, the overall performance is the best. We determine that this optimum is a result of two competing factors. If the passive section is too large, then the actuated portion is unable to generate substantial deflection to create sufficient thrust. On the other hand, a large actuated section leads to a bending pattern that is inefficient at generating thrust especially at higher frequencies.

关键词： Flexible plate Biomimetic Lattice Boltzmann Fluid-structure interaction Robotic fish Piezoelectric actuator