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Navigating the Challenges of Emerging Contaminants to Protect Human and Ecological Health

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Engineering 2024年第6期37卷 1-2页

作者： Jiuhui qu Michael R.Hoffmann gang Yu School of Environment Tsinghua UniversityBeijing 100084China Linde-Robinson Laboratories California Institute of TechnologyPasadenaCA 91125USA Advanced Interdisciplinary Institute of Environmental and Ecology Beijing Normal UniversityZhuhai 519000China

Emerging contaminants are defined as chemicals that are not currently(or have only recently been)regulated and about which there are concerns regarding their impact on human or ecological *** contaminants are widely detected in air,water,soil,sediment,and biotic *** is against this backdrop of urgency that we have curated this special issue titled“Emerging Contaminants Control:Science and Technology,”with the goal of uniting the latest scientific insights and pioneering strategies to address this global *** special issue embarks on a comprehensive examination of the emerging contaminants dilemma,covering aspects such as risk assessment,remediation technologies,environmental surveying,and the broader implications for *** a collection of articles,we probe deep into the core of this issue,showcasing studies that range from appraising environmental risks to forging new methods for treatment and scrutinizing the occurrence of contaminants across different environmental settings.

关键词： Ecological surveying environmental

Spear and Shield： Evolution of Integrated Circuit Camouflaging

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Journal of Computer Science & Technology 2018年第1期33卷 42-57页

作者： Xue-Yan Wang Qiang Zhou Yi-Ci Cai gang qu Department of Computer Science and Technology Tsinghua University Beijing 100083 China Department of Electrical and Computer Engineering UniversiLy of Maryland College Park MD 20740 U.S.A.

Intellectual property （IP） protection is one of the hardcore problems in hardware security. Semiconductor industry still lacks effective and proactive defense to shield IPs from reverse engineering （RE） based attacks. Integrated circuit （IC） camouflaging technique fills this gap by replacing some conventional logic gates in tile IPs with specially designed logic cells （called camouflaged gates） without changing the functions of tile IPs. The camouflaged gates can perform different logic functions while maintaining an identical look to RE attackers, thus preventing them from obtaining the layout information of the IP directly from RE tools. Since it was first proposed in 2012, circuit camouflaging has become one of the hottest research topics in hardware security focusing on two fundamental problems. How to choose the types of camouflaged gates and decide where to insert them in order to simultaneously minimize the performance overhead and optimize the RE complexity？ How can an attacker de-camouflage a camouflaged circuit and complete the RE attack？ In this article, we review the evolution of circuit camouflaging through this spear and shield race. First, we introduce the design methods of four different kinds of camouflaged ceils based on true/dummy contacts, static random access memory （SRAM）, doping, and emerging devices, respectively. Then we elaborate four representative de-camouflaging attacks： brute force attack, IC testing based attack, satisfiability-based （SAT-based） attack, and the circuit partition based attack, and the corresponding countermeasures： clique-based camouflaging, CamoPerturb, AND-tree camouflaging, and equivalent class based camouflaging, respectively. We argue that the current research efforts should be on reducing overhead introduced by circuit camouflaging and defeating decamouflaging attacks. We point out that exploring features of emerging devices could be a promising direction. Finally, as a complement to circuit camouflaging, we concl

关键词： circuit camouflaging reverse engineering intellectual property (IP) protection hardware security

Understanding and addressing the environmental risk of microplastics

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Frontiers of Environmental Science & Engineering 2023年第1期17卷 133-137页

作者： Han qu Hongting Diao Jiajun Han Bin Wang gang Yu College of Pharmacy The University of ArizonaTucsonAZ 85724USA Beijing Laboratory of Environmental Frontier Technology Beijing Key Laboratory of Emerging Organic Contaminants ControlSchool of EnvironmentTsinghua UniversityBeijing 100084China Department of Applied Chemistry China Agricultural UniversityBeijing 100193China

Over the past decades,the plastic production has been dramatically ***,a category of small plastic particles mainly with the shapes of fragments,fibers,or spheres,called microplastics(particles smaller than 5 mm)and nanoplastics(particles smaller than 1μm)have attracted particular *** of its wide distribution in the environment and potential adverse effects to animal and human,microplastic pollution has been reported as a serious environment problem receiving increased attention in recent *** one of the commonly detected emerging contaminants in the environment,recent evidence indicates that the concentration of microplastics show an increasing trend,for the reason that up to 12.7 million metric tons of plastic litter is released into aquatic environment from land-based sources each ***,microplastic exposure levels of model organisms in laboratory studies are usually several orders of magnitude higher than those found in environment,and the microplastics exposure conditions are also different with those observed in the ***,the detection of microplastics in feces indicates that they can be excreted out of the bodies of animal and ***,great uncertainties might exist in microplastics exposure and health risk assessment based on current studies,which might be *** reduce microplastic emission sources and hence minimize their environmental risks are *** promote the above policies,we must first overcome the technical obstacles of detecting microplastics in various samples.

关键词： Emerging contaminants Microplastics Environment risk Health effect

Passivity Analysis of Impulsive Complex Networks

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International Journal of Automation and computing 2011年第4期8卷 484-489页

作者： Jin-Liang Wang huai-Ning Wu Zhi-Chun gang Science and Technology on Aircraft Control Laboratory School of Automation Science and Electrical Engineering Beihang University Beijing 100191 PRC College of Mathematics Science Chongqing Normal University Chongqing 400047 PRC

In this paper, we first investigate input passivity and output passivity for a class of impulsive complex networks with time-varying delays. By constructing suitable Lyapunov functionals, some input passivity and output passivity conditions are derived for the impulsive complex networks. Finally, an example is given to show the effectiveness of the proposed criteria.

关键词： Impulsive complex networks time-varying delays input passive output passive Lyapunov functional.

Providing Virtual Cloud for Special Purposes on Demand in JointCloud Computing Environment

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Journal of Computer Science & Technology 2017年第2期32卷 211-218页

作者： Dong-gang Cao Member, CCF, IEEE, Bo An Pei-Chang Shi huai-Min Wang Key Laboratory of High Confidence Software Technologies (Peking University) Ministry of Education Beijing 100871 China National Key Laboratory for Parallel and Distributed Processing National University of Defense and Technology Changsha 410073 China

Cloud computing has been widely adopted by enterprises because of its on-demand and elastic resource usage paradigm. Currently most cloud applications are running on one single cloud. However, more and more applications demand to run across several clouds to satisfy the requirements like best cost efficiency, avoidance of vender lock-in, and geolocation sensitive service. JointCloud computing is a new research initiated by Chinese institutes to address the computing issues concerned with multiple clouds. In JointCloud, users＇ diverse and dynamic requirements on cloud resources axe satisfied by providing users virtual cloud （VC） for special purposes. A virtual cloud for special purposes is in essence a user＇s specific cloud working environment having the customized software stacks, configurations and computing resources readily available. This paper first introduces what is JointCloud computing and then describes the design rationales, motivation examples, mechanisms and enabling technologies of VC in JointCloud.

关键词： cloud computing JointCloud virtual cloud (VC) cloud working environment

FLOW STRUCTURE IN PARTIALLY VEGETATED RECTANGULAR CHANNELS

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Journal of Hydrodynamics 2010年第4期22卷 590-597页

作者： CHEN gang huai Wen-xin HAN Jie ZHAO Ming-deng State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan 430072 China

This article discusses the transverse distributions of the depth averaged velocity and the Reynolds stress in a steady uniform flow in partially vegetated rectangular *** momentum equation is expressed in dimensionless form and solved to obtain the depth averaged *** analytical solution of the velocity in dimensionless form shows that the depth-averaged velocity is determined by gravity and its distribution is mainly determined by the frictions due to water or *** analytical solution of the Reynolds stress is also obtained.A relationship between the second flow and the inertia is established and it is assumed that the former is proportional to the square of the depth averaged *** Acoustic Doppler Velocimeter（Micro ADV） was used to measure the steady uniform flow with emergent artificial rigid *** between the measured data and the computed results show that our method does well in predicting the transverse distributions of the stream-wise velocity and the Reynolds stress in rectangular channels with partially vegetations.

关键词： drag fbrce partially vegetated channel secondary currents velocity distribution

Mechanical properties and thermal deformation behavior of low-cost titanium matrix composites prepared by a structure-optimized Y_(2)O_(3) crucible

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Journal of Iron and Steel Research International 2024年第3期31卷 738-751页

作者： Qian Dang gang Huang Ye Wang Chi Zhang Guo-huai Liu Zhao-dong Wang The State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina School of Materials Science and Chemical Engineering Harbin University of Science and TechnologyHarbin 150004HeilongjiangChina School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870LiaoningChina

A porous yttrium oxide crucible with both thermal shock resistance and erosion resistance was developed by structural *** structure-optimized yttrium oxide crucible was proved to be suitable for melting highly reactive titanium ***-cost(TiB+Y2O_(3))-reinforced titanium matrix composites were prepared by vacuum induction melting using the prepared *** thermal deformation behavior and microstructure evolution of(TiB+Y2O_(3))-reinforced tita-nium matrix composites were investigated at deformation temperatures of 900-1100℃with strain rates of 0.001-1 *** results showed that the prepared yttrium oxide crucible had both thermal shock and erosion resistance,the low-cost titanium matrix composites could be prepared by the developed yttrium oxide crucibles which were homogeneous in composition and highly sensitive to strain rate and deformation temperature,and the peak and theological stresses decreased with increasing deformation temperature or decreasing strain *** addition,the average thermal deformation activation energy of the composites was calculated to be 574.6 kJ/mol by establishing the Arrhenius constitutive equation in consideration of the strain variables,and the fitting goodness between the predicted stress value and the measured value was 97.624%.The calculated analysis of the hot processing map showed that the best stable thermal deformation zone was located in the deformation temperature range of 1000-1100℃and strain rate range of 0.001-0.01 s^(-1),where the peak dissipation coefficient wasη=71%.In this zone,the deformation of the reinforcement and matrix was harmonious,the reinforcement was less likely to fracture,dynamic recrystallization occurred more fully and the alloy exhibited near steady rheological characteristics.

关键词： Yttrium oxide crucible Titanium matrix composite Thermal deformation behavior Constitutive equation Hot processing map Microstructure evolution

Roadmap for Managing SARS-CoV-2 and Other Viruses in the Water Environment for Public Health

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Engineering 2022年第5期8卷 139-144页

作者： gang Liu Jiuhui qu Joan Rose Gertjan Medema Key Laboratory of Drinking Water Science and Technology Research Centre for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Department of Fisheries and Wildlife Michigan State UniversityEast LansingMI 48823USA KWR Water Research Institute Nieuwegein 3433 PENetherlands Sanitary Engineering Department of Water ManagementFaculty of Civil Engineering and GeosciencesDelft University of TechnologyDelft 2628 CNNetherlands

The water sector needs to address viral-related public health issues,because water is a virus carrier,which not only spreads viruses(e.g.,via drinking water),but also provides information about the circu-lation of viruses in the community(e.g.,via sewage).It has been widely reported that waterborne viral pathogens are abundant,diverse,complex,and threatening the public health in both developed and developing ***,there is great potential for viral monitoring that can indicate biosafety,treatment performance and community *** developments in technology have been rising to meet the emerging challenges over the past *** the current coronavirus disease 2019(COVID-19)pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),the world’s attention is directed to the urgent need to tackle the most challenging public health issues related to waterborne *** on critical analysis of the water viral knowledge progresses and gaps,this article offers a roadmap for managing COVID-19 and other viruses in the water environments for ensur-ing public health.

关键词： Virus Water environment Viral indicators Sewage surveillance Biosafety

Study on Contact Algorithm of Dynamic Explicit FEM for Sheet Forming Simulation

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Wuhan University Journal of Natural Sciences 2001年第3期6卷 704-708页

作者： Zhang Hai-ming Dong Xiang-huai Li Zhi-gang State Key Laboratory of PFSDMT Huazhong Univ. of Sci./Technology Wuhan 430074 China

Based on existing algorithms, a newly developed contact search algorithm is proposed. The new algorithm consists of global search, local searching, local tracking and penetration calculation processes. It requires no iteration steps. It can deal with not only general tool surfaces with vertical walls, but also tool surfaces meshed with elements having very poor aspect ratios. It is demonstrated that the FE code employing this new contact search algorithm becomes more reliable, efficient and accurate for sheet metal forming simulation than conventional ones.

关键词： contact algorithm dynamic explicit FEM sheet metal forming