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Comparison of different chain n-fatty acids in modern plants on the Loess Plateau of China

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Frontiers of Earth Science 2020年第3期14卷 615-624页

作者： Jinzhao Liu zhisheng an State key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesCAS Center for Excellence in Quaternary Science and Global ChangeXi’an710061China School of Human Settlements and Civil Engineering Xi’an Jiaotong UniversityXi’an710049China

n-Fatty acids(n-FAs)are widely investigated in lake sediments,yet less attention has been given to soil sedimentary n-FAs primarily derived from terrestrial *** this study,we performed an analysis of n-FA distributions in modern plants on the Loess Plateau,*** showed that n-FAs were generally dominated by n-C16,and that short-chain(C16-C20),medium-chain(C22-C26)and long-chain(C28-C32)n-FAs accounted for 49.7%,33.7%and 16.6%,*** LTR(long-chain/total ratio),and medium-chain EOP(even/odd predominance)are likely to differentiate between dicots and monocots in modern *** is believed that this study will promote the paleo-application of soil sedimentary n-FAs on the Loess Plateau.

关键词： n-fatty acids terrestrial higher plants ChineseLoess Plateau

Pretreated methods on loess-palaeosol samples granulometry

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维普期刊数据库

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Chinese Science Bulletin 1998年第3期43卷 237-240页

作者： Huayu Lu zhisheng an Chinese Acad Sci State Key Lab Loess & Quaternary Geol Xian 710054 Peoples R China

Twenty representative samples were collected from the Chinese loess plateau and each sample was prepared in 6 different ways respectively in order to test the influences of pretreated methods on grain size measurement. The results show that (ⅰ) different pretreated methods can make a big difference for the samples granulometry; (ⅱ) soaking in distilled water for one day, and then treating with an ultrasonic machine for 10 min can make the sample dispersed.

关键词： loess deposit grain size pretreated method.

Distributed adaptive attitude synchronization of multiple spacecraft

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Science China(Technological Sciences) 2011年第8期54卷 1992-1998页

作者： LI ZhongKui DUAN zhisheng School of Automation Beijing Institute of Technology Beijing 100081 China State Key Lab. for Turbulence and Complex Systems Department of Mechanics and Aerospace Engineering College of Engineering Peking University Beijing 100871 China

This paper addresses the distributed attitude synchronization problem of multiple spacecraft with unknown inertia matrices. Two distributed adaptive controllers are proposed for the cases with and without a virtual leader to which a time-varying reference attitude is assigned. The first controller achieves attitude synchronization for a group of spacecraft with a leaderless communication topology having a directed spanning tree. The second controller guarantees that all spacecraft track the reference attitude if the virtual leader has a directed path to all other spacecraft. Simulation examples are presented to illustrate the effectiveness of the results.

关键词： attitude synchronization distributed control adaptive control multi-agent system

Distributed consensus for multiple Euler-Lagrange systems: An event-triggered approach

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Science China(Technological Sciences) 2016年第1期59卷 33-44页

作者： HUANG Na DUAN zhisheng ZHAO Yu State Key Laboratory for Turbulence and Complex Systems Department of Mechanics and Engineering Science College of EngineeringPeking University

Distributed consensus problems for multiple Euler-Lagrange systems are addressed on the basis of event-triggered information in this study. Distributed consensus protocols are first designed in terms of two event-triggered scenarios: a decentralized strategy and a distributed strategy. Sufficient conditions that guarantee the event-triggered consensus for multiple Euler-Lagrange systems are then presented, with the associated advantages of reducing controller update times. It is shown that the Zeno behavior of triggering time sequences is excluded for both strategies. Finally, multiple Euler-Lagrange systems that consist of six two-link manipulators are considered to illustrate the effectiveness of the proposed theoretical algorithms.

关键词： consensus event-triggered strategy Euler-Lagrange system distributed control

H_∞ CONTROL OF NETWORKED MULTI-AGENT SYSTEMS

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Journal of Systems Science & Complexity 2009年第1期22卷 35-48页

作者： Zhongkui LI zhisheng DUAN Lin HUANG State Key Lab for Turbulence and Complex Systems and Department of Mechanics and Aerospace Engineering College of Engineering Peking University Beijing 100871 China.

This paper concerns the disturbance rejection problem arising in the coordination control of a group of autonomous agents subject to external disturbances. The agent network is said to possess a desired level of disturbance rejection, if the H∞ norm of its transfer function matrix from the disturbance to the controlled output is satisfactorily small. Undirected graph is used to represent the information flow topology among agents. It is shown that the disturbance rejection problem of an agent network can be solved by analyzing the H∞ control problem of a set of independent systems whose dimensions are equal to that of a single node. An interesting result is that the disturbance rejection ability of the whole agent network coupled via feedback of merely relative measurements between agents will never be better than that of an isolated agent. To improve this, local feedback injections are applied to a small fraction of tile agents in the network. Some criteria for possible performance improvement are derived in terms of linear matrix inequalities. Finally, extensions to the case when communication time delays exist are also discussed.

关键词： Coordination control graph theory H∞ control linear matrix inequality (LMI) pinning control.

Molecular characterization of microbial communities in bioaerosols of a coal mine by 454 pyrosequencing and real-time PCR

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Journal of Environmental Sciences 2015年第4期27卷 241-251页

作者： Min Wei zhisheng Yu Hongxun Zhang College of Resources and Environment University of Chinese Academy of Sciences

Microbial diversity and abundance in bioaerosols of a coal mine were analyzed based on 454 pyrosequencing and real-time polymerase chain reaction（PCR）. A total of 37,191 high quality sequences were obtained and could be classified into 531, 1730 and 448 operational taxonomic units respectively for archaea, bacteria and fungi at 97% sequence similarity. The Shannon diversity index for archaea, bacteria and fungi was respectively 4.71, 6.29 and 3.86, indicating a high diversity in coal mine bioaerosols. Crenarchaeota, Proteobacteria and Ascomycota were the dominant phyla for archaea, bacteria and fungi, respectively. The concentrations of total archaea, bacteria and fungi were 1.44 × 10^8, 1.02 × 10^8 and 9.60 × 10^4cells/m^3, *** observed in bioaerosols suggested possible methane oxidation in the coal mine. The identified potential pathogens to coal miners, such as Acinetobacter schindleri,Aeromonas cavernicola, Alternaria alternata, Aspergillus penicillioides, Cladosporium cladosporioides,and Penicillium brevicompactum were also observed. This was the first investigation of microbial diversity and abundance in coal mine bioaerosols. The investigation of microbial communities would be favorable in promoting the progress of methane control based on microbial technique and concern on coal miners＇ health.

关键词： Microbial community Bioaerosols Methanotrophs Coal mine

Nickel sulfide modified TiO_2 nanotubes with highly efficient photocatalytic H_2 evolution activity

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Journal of Energy Chemistry 2016年第1期25卷 136-140页

作者： Jiasheng Huang zhisheng Shi Xinfa Dong School of Chemistry and Chemical Engineering South China University of Technology

TiO2 nanotubes（TNTs） with nickel sulfide（NiS） co-catalyst were prepared by a simple solvothermal method and characterized by X-ray diffraction, transmission electron microscope, N2-physisorption, UV–vis diffuse reflectance spectroscopy and photoluminescence spectroscopy. Loading NiS nano-clusters can significantly enhance the photocatalytic H2 evolution performance of TNTs. The optimum NiS loading content was found to be 8 wt% and the corresponding hydrogen production rate is ca. 7486 μmol/h/g, being about 79 times higher than that of pure TNTs. This enhancement of photocatalytic H2 evolution was attributed to the synergistic effect between NiS and TNTs.

关键词： Photocatalysis Hydrogen production TiO2 nanotubes NiS

Reasoning with Inconsistent Ontologies

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Tsinghua Science and Technology 2010年第6期15卷 687-691页

作者：方俊 zhisheng Huang School of Automation Northwestern Polytechnical University Xi'an 710072 China Computer Science Department Vrije Universiteit Amsterdam Amsterdam the Netherlands

Reasoning with inconsistent ontologies involves using an inconsistency reasoner to get meaningful answers from inconsistent ontologies. This paper introduces an improved inconsistency reasoner, which selects consistent subsets using minimal inconsistent sets and a resolution method, to improve the run-time performance of the reasoning processing. A minimal inconsistent set contains a minimal explanation for the inconsistency of a given ontology. Thus, it can replace the consistency checking operation, which is executed frequently in existing approaches. When selecting subsets of the inconsistent ontology, formulas which can be directly or indirectly resolved with the negation of the query formula are selected because only those formulas affect the consequences of the reasoner. Therefore, the complexity of the reasoning processing is significantly reduced. Tests show that the run-time performance of the inconsistency reasoner is significantly improved.

关键词： minimal inconsistent set (MIS) inconsistency reasoner resolvable relevance inconsistent ontologies

Throughput Servicing Time Allocation of Hybrid Storage System Based on Client Grouping Mechanism

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Chinese Journal of Electronics 2019年第1期28卷 62-70页

作者： HUO zhisheng XIAO Limin HE Zhenxue RONG Xiaoling State Key Laboratory of Software Development Environment School of Computer Science and Engineering Beihang University School of Information Science and Technology Hebei Agricultural University School of Communication Science Beijing Language and Culture University

The fair division theory has emerged as a promising approach for the throughput allocation of hybrid storage system. While most of them cause the unfair allocation of the throughput servicing time due to taking no consideration of clients’ request IO latencies. We propose one Servicing time allocation method based on the client grouping mechanism(STCG), STCG establishes fair allocation policies based on clients’ workload weights,which can achieve a fair throughput servicing time allocation, and can maximize the resource utilization. The experimental result shows that STCG’s allocation enjoys fair properties in each client group, and compared with the method proposd recently, STCG can improve the resource utilization about 12%–330%.

关键词： Hybrid storage system Throughput servicing time Fair allocation Client grouping