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Journal of Systems Science & Complexity 2018年第1期31卷 130-146页

作者： LIU Bin hill david john ZHANG Changfan SUN Zhijie Department of Information and Computing Science Hunan University of Technology Zhuzhou 412008 China Department of Electrical and Electronic Engineering The University of Hong Kong Hong Kong China School of Electrical and Information Engineering Hunan University of Technology Zhuzhou 412008 China Mork Family Department of Chemical Engineering and Materials Science Viterbi School of Engineering University of Southern California Los Angeles CA 90089 USA

This paper investigates the issue of stabilization for discrete-time dynamical systems（DDS）by event-triggered impulsive control（ETIC）. Based on some relatively simple threshold constants, three levels of event conditions are set and thus the ETIC scheme is designed. Three cases for ETIC with and without time-delays and data dropouts are studied respectively, and the criteria on exponential stability are derived for the controlled DDS. The stabilization in the form of exponential stability is achieved for DDS under the designed ETIC with or without time-delays. And in the case of the ETIC data dropouts, the conditions of exponential stabilization are derived for DDS and the maximal allowable dropout rates for ETIC are estimated. Finally, one example with numerical simulations is worked out for illustration.

关键词： Data dropout discrete-time dynamical systems event-triggered control exponential stability impulsive control stabilization time-delay

Evolution and maintenance of cooperation via inheritance of neighborhood relationship

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Chinese Science Bulletin 2013年第28期58卷 3491-3498页

作者： TAN ShaoLin Lü JinHu YU XingHuo hill david john The Key Laboratory of System and Control Institute of Systems ScienceAcademy of Mathematics and Systems ScienceChinese Academy of Sciences School of Electrical and Computer Engineering RMIT University Department of Electrical and Electronic Engineering The University of Hong Kong School of Electrical and Information Engineering University of Sydney

Cooperative behaviors are ubiquitous in nature and human *** is very important to understand the internal mechanism of emergence and maintenance of *** we know now,the offsprings inherit not only the phenotype but also the neighborhood relationship of their *** recent research results show that the interactions among individuals facilitate survival of cooperation through network reciprocity of clustering *** paper aims at introducing an inheritance mechanism of neighborhood relationship to explore the evolution of *** detail,a mathematical model is proposed to characterize the evolutionary process with the above inheritance *** analysis and numerical simulations indicate that high-level cooperation can emerge and be maintained for a wide variety of cost-to-benefit ratios,even if mutation happens during the evolving process.

关键词：合作机制邻里关系维护演变进化过程人类社会遗传机制数学模型

A Multi-parametric Programming Based Analytic Method to Compute Consumer Offer Curve for Reserves

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Journal of Modern Power Systems and Clean Energy 2022年第2期10卷 542-546页

作者： Weiye Zheng david J.hill Wenchuan Wu the School of Electrical Power Engineering South China University of TechnologyGuangzhouChina the Department of Electrical and Electronic Engineering The University of Hong KongHong KongChina the Department of Electrical Engineering Tsinghua UniversityBeijingChina

Abstract-An analytic method is proposed to compute the price-reserve offer curve at the consumer level in hierarchical direct load *** convexification of the consumer reserve provision is examined,and the analytic expression of the optimal solution within each critical region is ***,based on multi-parametric programming,a combinatorial enumeration method in conjunction with efficient reduction and pruning strategy is proposed to compute the optimal response of consumers in the whole price *** tests along with an application example in the bi-level aggregator pricing problem demonstrate the merit of this method.

关键词： Direct load control multi-parametric programming price-reserve offer curve analytic solution

Functional origins of the vertebrate cerebellum from a sensory processing antecedent

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Current Zoology 2010年第3期56卷 277-284页

作者： john MONTGOMERY david BODZNICK Leigh Marine Laboratory and School of Biological Sciences University of Auckland Department of Biology Wesleyan University

The structure of the cerebellar cortex is remarkably similar across vertebrate phylogeny. It is well developed in basaljawed fishes, such as sharks and rays with many of the same cell types and organizational features found in other vertebrategroups, including mammals. In particular, the lattice-like organization of cerebellar cortex (with a molecular layer of parallel fibres,interneurons, spiny Purkinje cell dendrites, and climbing fires) is a common defining characteristic. In addition to the cerebellarcortex, fishes and aquatic amphibians have a variety of cerebellum-like structures in the dorso-lateral wall of the *** structures are adjacent to, and in part, contiguous with, the cerebellum. They derive their cerebellum-like name from thepresence of a molecular layer of parallel fibers and inhibitory interneurons, which has striking organizational similarities to themolecular layer of the cerebellar cortex. However, these structures also have characteristics which differ from the cerebellum. Forexample, cerebellum-like structures do not have climbing fibres, and they are clearly sensory. They receive direct afferent inputfrom peripheral sensory receptors and relay their outputs to midbrain sensory areas. As a consequence of this close sensory association,and the ability to characterise their signal processing in a behaviourally relevant context, good progress has been made indetermining the fundamental processing algorithm in cerebellar-like structures. In particular, we have come to understand thecontribution to signal processing made by the molecular layer, which provides an adaptive filter to cancel self-generated noise inelectrosensory and lateral line systems. Given the fundamental similarities of the molecular layer across these structures, coupledwith evidence that cerebellum-like structures may have been the evolutionary antecedent of the cerebellum, we address the question:do both share the same functional algorithm? [Current Zoology 56 (3):

关键词： Origin Vertebrate Cerebellum

Optimal coordinated voltage control of power systems

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第2期7卷 257-262页

作者：李艳君 hill david J 吴铁军 Institute of Intelligent Systems and Decision Making Zhejiang University Hangzhou 310027 China Department of Electronic Engineering City University of Hong Kong Hong Kong China

An immune algorithm solution is proposed in this paper to deal with the problem of optimal coordination of local physically based controllers in order to preserve or retain mid and long term voltage stability. This problem is in fact a global coordination control problem which involves not only sequencing and timing different control devices but also tuning the parameters of controllers. A multi-stage coordinated control scheme is presented, aiming at retaining good voltage levels with minimal control efforts and costs after severe disturbances in power systems. A self-pattem-recognized vaccination procedure is developed to transfer effective heuristic information into the new generation of solution candidates to speed up the convergence of the search procedure to global optima. An example of four bus power system case study is investigated to show the effectiveness and efficiency of the proposed algorithm, compared with several existing approaches such as differential dynamic programming and tree-search.

关键词： Power systems Voltage control Immune algorithm Global optimization

Advances in Stability Theory for Complex Systems and Networks

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Semi-transparent,flexible,and electrically conductive silicon mesh by capillarity-driven welding of vapor-liquid-solid-grown nanowires over large areas

第二十七届中国控制会议

作者： hill david J. Research School of Information Sciences and Engineering Australian National University

ISBN: (纸本)9787811243901

Throughout natural and engineered systems,questions about stability always *** a power network avoid blackouts?Will the Internet avoid traffic congestion?Will a species population survive?Engineered systems now have features comparable to living systems,namely massive scale,high degrees of nonlinearity,uncertainty and *** systems are summarized as being *** important class of such systems has a well-defined network structure where large numbers of nodes,typically described by nonlinear dynamical systems,are connected by *** theory faces many challenges in providing tools to assess stability and instability for such complex *** this assessment must allow for layers of feedback control which have been implemented to regulate local and global *** paper will describe the advancement of stability theory to deal with complex systems with some emphasis on interconnected systems featuring feedback and network structures.

关键词： Stability Complex systems Networks

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Nano Research 2020年第5期13卷 1465-1471页

作者： Thomas A.Celano Seokhyoung Kim david J.hill James F.Cahoon Department of Chemistry University of North Carolina at Chapel HillChapel HillNC 27599-3290USA

Bottom-up synthesis of semiconductor nanowires(NWs)by the vapor-liquid-solid(VLS)mechanism has enabled diverse technological applications for these *** metallic NWs,however,it has been challenging to form large-area interconnected NW ***,we generate centimeter-scale meshes of mechanically and electrically interconnected Si NWs by sequentially growing,collapsing,and joining the NWs using a capillarity-driven welding *** fabricate meshes from VLS-grown NWs ranging in diameter from 20 to 100 nm and find that the meshes are three-dimensional with a thickness ranging from^1 to^10 microns depending on the NW *** extinction measurements reveal that the networks are semi-transparent with a color that depends on the absorption and scattering characteristics of individual ***,active voltage contrast imaging of both centimeter-and micron-scale meshes reveals widespread electrical *** a sacrificial layer,we demonstrate that the mesh can be liberated from the growth substrate,yielding a highly flexible and transparent *** transport measurements both on the growth substrate and on liberated,flexible films reveal electrical conduction across a centimeter scale with a sheet resistance of^160-180 kΩ/square that does not change significantly upon *** the ability to encode complex functionality in semiconductor NWs through the VLS process,we believe these meshes of networked NWs could find application as neuromorphic memory,electrode scaffolds,and bioelectronic interfaces.

关键词： semiconductor nanowire conductive network flexible electronics welding thermal annealing active-voltage contrast

Characterization of the proteases in the midgut of the xylophagous larvae of Oemona hirta （Coleoptera： Cerambycidae）

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Insect Science 2009年第5期16卷 381-386页

作者： Brian david Shaw john Tane Christeller The New Zealand Institute of Plant and Food Research Palmerston North New Zealand

The protein digestive capability of the larvae of the longhorn beetle （Oemona hirta, Coleoptera： Cerambycidae, Fabricius, 1775） was investigated. This species feeds only on wood where there is a high proportion of vascular tissue. The pH of the midgut, the major digestive organ, was alkaline and protein hydrolysis was maximal at alkaline pH. Use of specific synthetic peptide substrates showed that the major protease activities were the endopeptidases, trypsin and chymotrypsin-like activity, and the exopeptidase, leucine aminopeptidase and the pH curves corresponded to that with protein substrate. Studies using a range ofserine protease inhibitors as well as specific inhibitors ofmetalloproteases, cysteine proteases and aspartate proteases confirmed a serine protease-based digestive system similar to earlier reports of sapwood-feeding Cerambycids. Control of these insect pests using protease inhibitors is discussed.

关键词： chymotrypsin digestion Oemona hirta trypsin xylophagy

Micro/nano Indentation and Single Grit Diamond Grinding Mechanism on Ultra Pure Fused Silica

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Chinese Journal of Mechanical Engineering 2011年第6期24卷 963-970页

作者： ZHAO Qingliang GUO Bing STEPHENSIN david CORBETT john School of Mechatronics Engineering Harbin Institute of Technology Harbin 150001 China Materials Department Cranfield University Cranfield Bedford MK43 OAL UK School of Applied Sciences Cranfield University Cranfield Bedford MK43 OAL UK

The existing research about ductile grinding of fused silica glass was mainly focused on how to carry out ductile regime material removal for generating very ＂smoothed＂ surface and investigate the machining-induced damage in the grinding in order to reduce or eliminate the subsurface *** brittle/ductile transition behavior of optical glass materials and the wear of diamond wheel are the most important factors for ductile grinding of optical *** this paper,the critical brittle/ductile depth,the influence factors on brittle/ductile transition behavior,the wear of diamond grits in diamond grinding of ultra pure fused silica（UPFS） are investigated by means of micro/nano indentation technique,as well as single grit diamond grinding on an ultra-stiff machine tool,Tetraform ＂C＂.The single grit grinding processes are in-process monitored using acoustic emission（AE） and force dynamometer *** wear of diamond grits,morphology and subsurface integrity of the machined groves are examined with atomic force microscope（AFM） and scanning electron microscope（SEM）.The critical brittle/ductile depth of more than 0.5 μm is *** compared to the using roof-like grits,by using pyramidal diamonds leads to higher critical depths of scratch with identical grinding ***,the influence of grit shapes on the critical depth is not significant as *** grinding force increased linearly with depth of cut in the ductile removal regime,but in brittle removal regime,there are large fluctuations instead of forces *** SEM photographs of the cross-section profile show that the median cracks dominate the crack patterns beneath the single ***,The SEM photographs show multi worn patterns of diamond grits,indicating an inhomogeneous wear mechanism of diamond grits in grinding of fused silica with diamond grinding *** proposed research provides the basal technical theory for improving the ultra-precision grinding of UPFS.

关键词： ultra pure fused silica (UPFS) micro/nano indentation single grit diamond grinding ductile material removal subsurface integrity diamond grits wear

Soybean aphid intrabiotype variability based on colonization of specific soybean genotypes

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Insect Science 2015年第6期22卷 785-792页

作者： Michelle Pawlowski Curtis B. hill david J. Voegtlin Glen L. Hartman Department of Crop Sciences National Soybean Research Center University of Illinois Urbana Illinois USA Center for EconomicEntomology Illinois Natural History Survey University of Illinois Champaign Illinois USA USDA Agricultural Research Service National Soybean Research Center University of Illinois Urbana Illinois USA

The soybean aphid, Aphis glycines Matsumura （Hemiptera： Aphididae）, is one of the most destructive insect pests on soybeans in the United States. One method for managing this pest is through host plant resistance. Since its arrival in 2000, 4 aphid biotypes have been identified that are able to overcome soybean aphid resistance （Rag） genes. A soybean aphid isolate collected from Moline, Illinois readily colonized soybean plants with the soybean aphid resistance gene Rag2, unlike biotypes 1 and 2, but similar to soybean aphid biotype 3. Two no-choice experiments compared the virulence of the Moline isolate with biotype 3. In both experiments, differences in aphid population counts were not significant （P 〉 0.05） on soybean genotypes LD08-12957a （Rag2） and LD11-5413a （Rag2）, but the aphid counts for the Moline isolate were significantly （P 〈 0.05） lower than the aphid counts for the biotype 3 isolate on the soybean genotypes Dowling （Rag1）, LD05-16611 （Rag1）, LD11-4576a （Rag1）, and P1567598B （raglb and rag3）. The Moline isolate was a variant of aphid biotype 3, which is the first report showing that soybean aphid isolates classified as the same biotype, based on virulence against specific Rag genes, can differ in aggressiveness or ability to colonize specific host genotypes.

关键词： Aphis glycines biotype biotype variant soybean soybean aphid resistance