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The H_∞ synchronization of nonlinear Bloch systems via dynamic feedback control approach

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chinese Physics B 2011年第7期20卷 101-106页

作者： D.H. Ji J.H. Koo S.c. Won Ju H. Park Mobile communication Division Digital Media and Communications Samsung Electronics Co. Ltd 416-2 Maetan-Dong Suwon 443-803 Republic of Korea Department of Electronic and Electrical Engineering Pohang University of Science and Technology San 31 Hyoja-Dong Pohang 790-784 Republic of Korea Department of Electrical Engineering Yeungnam University 214-1 Dae-Dong Kyongsan 712-749 Republic of Korea

We consider an H∞ synchronization problem in nonlinear Bloch systems. Based on Lyapunov stability theory and linear matrix inequality formulation, a dynamic feedback controller is designed to guarantee asymptotic stability of the master-slave synchronization. Moreover, this controller reduces the effect of an external disturbance to the H∞ norm constraint. A numerical example is given to validate the proposed synchronization scheme.

关键词： H∞ synchronization Bloch system dynamic control linear matrix inequality

IGNITING SHS BY LASER AND ITS APPLIcATION TO SELEcTIVE LASER SINTERING OF METALLIc POWDER MATERIAL

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Acta Metallurgica Sinica(English Letters) 2004年第5期17卷 694-704页

作者： Y.S.Shi S.c.chen X.L.Lu S.H.Huang StateKeyLaboratoryofPlasticFormingSimulationandDie＆MouldTechnology SchoolofMaterialScienceandEngineeringHuazhongUniversityofScienceandTechnologyWuhan430074China

How to directly fabricate metallic functional parts with selective laser sintering (SLS) process is a potential technique that scientists are researching. Existent problems during directly fabricating metal part by use of SLS are analyzed. For the sake of solving the problems, a new idea of adding self-propagating high-temperature synthesis (SHS) material into metallic powder material to form new type of SLS metallic powder material is put forward. This powder material can release controllable amount of heat during its interaction with the laser beam energy to reduce the requirement to laser power during directly sintering metallic part, to prolong the time of metallic liquid phase existing, and to improve the intensity and accuracy of SLS part. For this reason, SHS material′s interaction with the cO2 laser beam energy is researched, which proves that cO2 laser beam energy may instantly ignite SHS reaction. On the basis of the above-mentioned researches, the effect of sintering the metal powder material mixing SHS material with cO2 laser is also researched, which shows: there is an optimal blending ratio of various material in the new metallic powder material. Under the optimal blending ratio and SLS process parameters, this new metallic powder material can indeed release amount of heat and SHS reaction may be controlled within the laser sintering. This research result makes it possible that the metallic part is directly sintered with small cO2 laser (less than 50W), which may greatly reduce the volume, cost and running expenditure of SLS machine, be propitious to application.

关键词： selective laser sintering (SLS) self-propagating high-temperaturesynthesis (SHS) ignition time metallic powder material,metallic part

Ground states, solitons and spin textures in spin-1 Bose-Einstein condensates

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Frontiers of physics 2013年第3期8卷 302-318页

作者： Shu-Wei Song Lin Wen chao-Fei Liu S.-c. Gou Wu-Ming Liu Beijing National Laboratory for condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China School of Science Jiangxi University of Science and Technology Ganzhou 341000 China Department of Physics National Changhua University of Education Changhua 50058 Taiwan China

We present an overview of our recent theoretical studies on the quantum phenomena of the spin-1 Bose Einstein condensates, including the phase diagram, soliton solutions and the formation of the topological spin textures. A brief exploration of the effects of spin-orbit coupling on the ground-state properties is given. We put forward proposals by using the transmission spectra of an optical cavity to probe the quantum ground states： the ferromagnetic and polar phases. Quasi-one-dimension solitons and ring dark solitons are studied. It is predicted that characteristics of the magnetic solitons in optical lattice can be tuned by controlling the long-range light-induced and static magnetic dipole- dipole interactions; solutions of single-component magnetic and single-, two-, three-components polar solitons are found; ring dark solitons in spin-1 condensates are predicted to live longer lifetimes than that in their scalar counterparts. In the formation of spin textures, we have considered the theoretical model of a rapidly quenched and fast rotating trapped spin-1 Bose Einstein condensate, whose dynamics can be studied by solving the stochastic projected Gross-Pitaevskii equations. Spontaneous generation of nontrivial topological defects, such as the hexagonal lattice skyrmions and square lattice of half-quantized vortices was predicted. In particular, crystallization of merons （half skyrmions） can be generated in the presence of spin-orbit coupling.

关键词： Bose-Einstein condensate spinor vortex lattice soliton spin orbit coupling

The pervasive effects of lighting environments on sensory drive in bluefin killifish： an investigation into male/male competition, female choice, and predation

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current Zoology 2018年第4期64卷 499-512页

作者： Lisa D. MITcHEM Shannon STANIS Nicholas M. SUTTON Zachary TURNER Rebecca c. FULLER School of Integrative Biology University of Illinois Urbana IL 61801 USA Department of Biology University of Virginia Charlottesville VA 22904 USA Department of Mathematics University of Illinois Urbana IL 61801 USA

Sensory drive predicts that the conditions under which signaling takes place have large effects on signals, sensory systems, and behavior. The coupling of an ecological genetics approach with sen sory drive has been fruitful. An ecological genetics approach compares populations that experi ence different environments and asks whether population differences are adaptive and are the result of genetic and/or environmental variation. The multifaceted effects of signaling environ ments are wellexemplified by the bluefin killifish. In this system, males with blue anal fins are abundant in tanninstained swamps that lack UV/blue light but are absent in clear springs where UV/blue light is abundant. Past work indicates that lighting environments shape genetic and envir onmental variation in color patterns, visual systems, and behavior. Less is known about the select ive forces creating the across population correlations between UV/blue light and the abundance of blue males. Here, we present three new experiments that investigate the roles of lighting environ ments on male competition, female mate choice, and predation. We found strong effects of lighting environments on male competition where blue males were more likely to emerge as dominant in teastained water than in clear water. Our preliminary study on predation indicated that blue males may be less susceptible to predation in teastained water than in clear water. However, there was little evidence for female preferences favoring blue males. The resulting pattern is one where the effects of lighting environments on genetic variation and phenotypic plasticity match the direction of selection and favor the expression of blue males in swamps.

关键词： Lucania goodei adaptive plasticity intrasexual selection male competition private communication predation

TENSILE TESTING OF c/c cOMPOSITES AT HIGH TEMPERATURES

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Acta Metallurgica Sinica(English Letters) 1999年第1期12卷 97-103页

作者： Zhou, S.R. Qiao, S.R. Bai, S.H. Tian, c.S. Northwestern Polytechnical Univ Xi'an China

The tensile properties of three different carbonfiberreinforced carbon composites (c/c), mat c/c, 2D laminate and 4D c/c, were investigated under the combined influence of temperature and loading rate. From the experiments the following could be concluded: loading rate between 10-1-10 mm/min was valid; the fracture stress of the three kinds of c/c composites increased with increasing temperature in the range from room temperature to 1900, and the initial modulus of 2D laminate c/c composites increased with the increase of temperature up to 2000.

关键词： tensile testing c/c composite high temperature mechanical property

STAG-cNS： An Order-Aware conserved Noncoding Sequences Discovery Tool for Arbitrary Numbers of Species

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Molecular Plant 2017年第7期10卷 990-999页

作者： Xianjun Lai Sairam Behera Zhikai Liang Yanli Lu Jitender S. Deogun James c. Schnable Department of Agronomy and Horticulture Center for Plant Science innovation University of Nebraska-Lincoln Lincoln NE 68588 USA Department of computer Science and Engineering University of Nebraska-Lincoln Lincoln NE 68588 USA Maize Research Institute Sichuan Agricultural University Chengdu 611130 China

One method for identifying noncoding regulatory regions of a genome is to quantify rates of divergence between related species, as functional sequence will generally diverge more slowly. Most approaches to identifying these conserved noncoding sequences （cNSs） based on alignment have had relatively large minimum sequence lengths （≥15 bp） compared with the average length of known transcription factor binding sites. To circumvent this constraint, STAG-cNS that can simultaneously integrate the data from the promoters of conserved orthologous genes in three or more species was developed. Using the data from up to six grass species made it possible to identify conserved sequences as short as 9 bp with false discovery rate ≤0.05. These cNSs exhibit greater overlap with open chromatin regions identified using DNase I hypersensitivity assays, and are enriched in the promoters of genes involved in transcriptional regulation. STAG-cNS was further employed to characterize loss of conserved noncoding sequences associated with retained duplicate genes from the ancient maize polyploidy. Genes with fewer retained cNSs show lower overall expression, although this bias is more apparent in samples of complex organ systems containing many cell types, suggesting that cNS loss may correspond to a reduced number of expression contexts rather than lower expression levels across the entire ancestral expression domain.

关键词： conserved noncoding sequence comparative genomics suffix tree longest path algorithm grain crops

Landscape and scale-dependent spatial niches of bats foraging above intensively used arable fields

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Ecological Processes 2017年第1期6卷 249-263页

作者： Olga Heim Lukas Lorenz Stephanie Kramer-Schadt Kirsten Jung christian c.Voigt Jana A.Eccard Leibniz Institute for Zoo and Wildlife Research Alfred-Kowalke-Str.1710315 BerlinGermany Animal Ecology Institute of Biochemistry and BiologyUniversity of PotsdamMaulbeerallee 114469 PotsdamGermany Institute of Evolutionary Ecology and conservation Genomics University of UlmAlbert-Einstein-Allee 1189069 UlmGermany Department of Animal Behaviour Freie Universität BerlinTakustr.314195 BerlinGermany

Introduction:Bats are threatened by agricultural intensification,and although bat ecology in agricultural landscapes is in the focus of current research,the effects of interacting spatiotemporal factors on species-specific bat activity above farmland remain *** aim was to identify spatiotemporal factors and their interactions relevant for the activity of bat species above conventionally managed arable ***:We repeatedly monitored relative bat activity above open arable fields in Germany using acoustic *** used site-related biotic and abiotic factors and landscape characteristics across five spatial scales,their combinations,and interactions to identify those factors which best explain variation in bat ***:Numerous interactions between landscape characteristics and the insect abundance affected bat activity above *** instance,Pipistrellus pipistrellus became more active with increasing insect abundance,but only above fields with a low proportion of woody vegetation cover in the ***,the level of bat activity in summer depended on landscape *** example,the activity of Pipistrellus nathusii was relatively low in summer above fields that were surrounded by vegetation patches with a high degree of edge complexity(e.g.,hedgerow).However,the activity remained at a relatively high level and did not differ between seasons above fields that were surrounded by vegetation patches with a low degree of edge complexity(e.g.,roundly shaped forest patch).conclusions:Our results revealed that landscape characteristics and their interactions with insect abundance affected bat activity above conventionally managed fields and highlighted the opportunistic foraging behavior of *** improve the conditions for bats in agricultural landscapes,we recommend re-establishing landscape heterogeneity to protect aquatic habitats and to increase arthropod availability.

关键词： AgroScapeLabs European bat species Agriculture Landscape Multi-scale habitat modeling Ecosystem service conservationAgroScapeLabs European bat species Agriculture Landscape Multi-scale habitat modeling Ecosystem service conservation

Heavy Metals in Brown Rice(Oryza sativa L.) and Soil After Long-Term Irrigation of Wastewater Discharged from Domestic Sewage Treatment Plants

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Pedosphere 2011年第5期21卷 621-627页

作者： B.Y.cHUNG c.H.SONG B.J.PARK J.Y.cHO Advanced Radiation Technology Institute Korea Atomic Energy Research Institute(KAERI) Korea Testing & Research Institute(KTR) Department of Horticultural Science Chungbuk National University Department of Bio-environmental chemistry Chonbuk National University

A pot experiment was conducted in a plastic film house to evaluate the translocation and uptake of heavy metals(Pb,cd,cu,and Zn) into brown rice(Oryza sativa L.) and the heavy metals residues in soils which had previously been irrigated with domestic wastewater for a long time(3 years).The range of Pb,cd,cu,and Zn was 5.10 ± 0.01,0.105 ± 0.017,5.76 ± 0.42,and 23.56 ± 1.40 mg kg-1,respectively in the domestic wastewater-irrigated soil,and 0.370 ± 0.006,0.011 ± 0.001,0.340 ± 0.04,and 2.05 ± 0.18 mg kg-1,respectively,in the domestic wastewater-irrigated brown *** results indicated that application of domestic wastewater to arable land slightly increased the levels of Pb,cd,cu,and Zn in soil and brown rice(P concentrations of heavy metals in brown rice were lower than the recommended tolerable levels proposed by the Joint FAO/WHO Expert committee on Food ***,the continuous monitoring and pollution control of hazardous materials from domestic wastewater are needed in order to prevent excessive build-up of heavy metals in the food chain.

关键词： accumulation domestic wastewater ground water irrigation P2O5 total N

EFFEcTS OF ce ON cORROSION RESISTANcE OF AZ91D MAGNESIUM ALLOY

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Acta Metallurgica Sinica(English Letters) 2005年第2期18卷 129-136页

作者： Z.H.Huang X.F.Guo Z.M.Zhang c.J.Xu SchoolofMaterialsScienceandEngineering Xi＇anUniversityofTechnologyXi＇an710048China

As-cast and corrosive microstructures of AZ91D alloy containing various ce contents were observed by optical microscope (OM). The phase compositions of the alloys before and after the corrosion were analyzed by X-ray diffraction (XRD). Meanwhile, the corrosion resistance of the alloys was tested by weight loss and potentiodynamic polarization curve methods respectively. The results show that rod-like Al4ce phase is formed in AZ91D alloy containing certain ce content and as-cast microstructures are refined. AZ91D-0.7%ce alloy has good grain refinement effect. The addition of ce can reduce the corrosion rate and corrosion current density of AZ91D alloy and those of AZ91D-0.1%ce alloy reach the minimum, which are 0.35mg/(cm2·d) and 2.761μA/cm2 with 75% and 86% reduction, respectively. The increasing volume fraction and reticular degree of β phase can improve the corrosion resistance of the alloys.

关键词： AZ91D magnesium alloy ce modification microstructure corrosion resistance