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Insect Science 2015年第2期22卷 165-177页

作者： Sara l. Goodacre Claudia Fricke Oliver Y. Martin School of Biology University of Nottingham Queen's Medical Centre Nottingham NG7 2UH United Kingdom Institute for Evolution and Biodiversity University of Muenster Muenster D-48 149 Germany ETH ZOrich Experimental Ecology Institute for IntegrativeBiology D-USYS CH-8092 ZOrich Switzerland

Reproductive parasites such as Wolbachia are extremely widespread amongst the arthropods and can have a large influence over the reproduction and fitness of their hosts. Undetected infections could thus confound the results of a wide range of studies that focus on aspects of host behavior, reproduction, fitness, and degrees of reproductive isolation. This potential problem has already been underlined by work investigating the in- cidence of Wolbachia infections in stocks of the model system Drosophila melanogaster. Here we survey a range of lab stocks of further commonly used model arthropods, fo- cusing especially on the flour beetles Tribolium castaneum and Tribolium confusum, the cowpea weevil Callosobruchus maculatus and related species （Coleoptera： Tenebrionidae and Bruchidae）. These species are widespread stored product pests so knowledge of infec- tions with symbionts further has potential use in informing biocontrol measures. Beetles were assessed for infection with 3 known microbial reproductive parasites： Wolbachia, Rickettsia, Spiroplasma. Infections with some of these microbes were found in some of the lab stocks studied, although overall infections were relatively rare. The consequences of finding infections in these or other species and the type of previous studies likely to be affected most are discussed.

关键词： Coleoptera reproductive isolation reproductive parasite sexual conflict sexual selection Wolbachia

Behavior modeling and verification of movement authority scenario of Chinese Train Control System using AADl

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Science China(Information Sciences) 2015年第11期58卷 125-144页

作者： AHMAD Ehsan DONG YunWei lARSON Brian lü JiDong TANG Tao ZHAN NaiJun School of Computer Science Northwestern Polytechnical University State Key laboratory of Computer Science Institute of Software Chinese Academy of Sciences Computing and Information Systems Kansas State University State Key laboratory of Rail Traffic Control and Safety Beijing Jiaotong University

Train control systems like most digital controllers are, by definition, hybrid systems as they interact with or try to control some aspects of the physical world. Detailed behavior modeling with constraints specification and formal verification, required for reliability prediction, is a great challenge for hybrid system *** control systems further intensify this challenge with extensive interaction between computing units and their physical environment and their mutual dependence on each other. In this paper, we investigate behavior modeling and formal verification of Chinese Train Control System level 3(CTCS-3) using Architectural Analysis & Design language(AADl) to cope with this challenge. AADl is an architecture description language for embedded systems and is based on model-based engineering paradigm. Along with structural modeling of embedded systems using the core language constructs, AADl also provides support for language extension through annex sublanguages. In system requirements specification document, the behavior of the CTCS-3 is specified as a set of basic operation scenarios that cooperate with each other to achieve safe and secure functionality of *** Authority(MA) scenario, explored in this paper, is considered as a basic and most crucial scenario to prevent trains from colliding with each other. The detailed discrete behavior of control system is modeled and verified using the Behavior language for Embedded Systems with Software(BlESS) annex sublanguage of AADl, and the continuous behavior of train with the cyber–physical interaction(communication between train and control system) is modeled using the Hybrid annex sublanguage. The behavior of the MA scenario at system level is verified using the Hybrid Hoare logic theorem prover. Behavior constraints are specified as assertions using first-order logic formulas augmented with a simple temporal operator.

关键词： AADl behavior modeling BlESS annex CTCS hybrid annex train control system

Implementation of Caterpillar Inspired Rolling Gait and Nonlinear Control Strategy in a Spherical Robot

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Journal of Bionic Engineering 2018年第2期15卷 313-328页

作者： Abhra Roy Chowdhury Gim Song Soh Shaohui Foong Kristin l. Wood Temasek laboratories Engineering Product Development Pillar Singapore University of Technology and Design Singapore 487372 SUTD-MIT International Design Centre Singapore University of Technology and Design Singapore 487372

This paper presents a novel Central Pattern Generator （CPG） based rolling gait generation in a small-sized spherical robot and its nonlinear control mechanism. A rhythmic rolling pattern mimicking Pleurotya caterpillar is produced for the spherical robot locomotion. A synergetically combined feedforward-feedback control strategy is proposed. The feedforward component is generated from centrally connected network of CPGs in conjunction with nonlinear robot dynamics. Two nonlinear feedback control methods namely integral （first order） Sliding Mode Control （SMC） and High （or second） Order Sliding Mode Control （HOSMC） are proposed to regulate robot stability and gait robustness in the presence of matched parameter uncertainties and bounded external disturbances. Design, implementation and experimental evaluation of both roll gait control strategies for the spherical robot are done on smooth （indoor） and irregular （outdoor） ground surfaces, The performance of robot control is quantified by measuring the roll angle stability, phase plane convergence and wheel velocities. Experimental results show that proposed novel strategy is efficient in producing a stable rolling gait and robust control of a spherical robot on two different types of surfaces. It further shows that proposed high HOSMC strategy is more efficient in robust rolling gait control of a spherical robot compared to an integral first-order SMC on two different ground conditions.

关键词： bioinspired spherical robot rolling gait CPG rolling friction integral first-order SMC control HOSMC

luminescence properties of dysprosium doped YVO_4 phosphor

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Journal of Rare Earths 2018年第12期36卷 1245-1249页

作者： H.J.Rajendra C.PANDurangappa D.l.Monika Department of Physics RNS Institute of TechnologyChannasandra Department of Physics SJB Institute of Technology

Trivalent dysprosium(Dy) activated nanocrystalline yttrium vanadate(YVO) phosphor was synthesized via co-precipitation method. The prepared samples were characterized by X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR), scanning electron microscopy(SEM), optical absorption and photo luminescence(Pl) techniques. The XRD patterns reveal the tetragonal crystalline phase. SEM images reveal that Dy doped YVOnanocrystals are agglomerated. EDAX confirms the formation of YVO:Dy. FTIR spectrum shows two strong absorption bands at 459 and 761 cm. Optical absorption spectrum showed the surface defects in the as-prepared samples. The Pl emission spectrum shows two characteristic emission bands at 485 and 575 nm. The strong yellow emission peak at 575 nm is assigned to ~4 F→~6 Hhyper sensitive transition of Dyions, Study of CIE chromaticity diagram indicates the suitability of the phosphor for the development of yellow-green lEDs.

关键词： Precipitation Yttrium vanadate Dysprosium X-ray diffraction Photoluminescence Rare earths

Sensitivity of the Simulation of Tropical Cyclone Size to Microphysics Schemes

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Advances in Atmospheric Sciences 2016年第9期33卷 1024-1035页

作者： Kelvin T.F.CHAN Johnny C.l.CHAN School of Energy and Environment City University of Hong Kong

The sensitivity of the simulation of tropical cyclone （TC） size to microphysics schemes is studied using the Advanced Hurricane Weather Research and Forecasting Model （WRF）. Six TCs during the 2013 western North Pacific typhoon season and three mainstream microphysics schemes-Ferrier （FER）, WRF Single-Moment 5-class （WSM5） and WRF Single-Moment 6-class （WSM6）-are investigated. The results consistently show that the simulated TC track is not sensitive to the choice of microphysics scheme in the early simulation, especially in the open ocean. However, the sensitivity is much greater for TC intensity and inner-core size. The TC intensity and size simulated using the WSM5 and WSM6 schemes are respectively higher and larger than those using the FER scheme in general, which likely results from more diabatic heating being generated outside the eyewall in rainbands. More diabatic heating in rainbands gives higher inflow in the lower troposphere and higher outflow in the upper troposphere, with higher upward motion outside the eyewall. The lower-tropospheric inflow would transport absolute angular momentum inward to spin up tangential wind predominantly near the eyewall, leading to the increment in TC intensity and size （the inner-core size, especially）. In addition, the inclusion of graupel microphysics processes （as in WSM6） may not have a significant impact on the simulation of TC track, intensity and size.

关键词： tropical cyclone microphysics size intensity track numerical modelling

Monte Carlo generator photon jets used for luminosity at e^+e^- colliders

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Chinese Physics C 2010年第6期34卷 877-882页

作者： G.V.Fedotovich E.A.Kuraev A.l.Sibidanov Budker Institute of Nuclear Physics Novosibirsk State University Joint Institute of Nuclear Research

A Monte-Carlo Generator Photon Jets （MCGPJ） to simulate Bhabha scattering as well as production of two charged muons and two photons events is discussed. The theoretical precision of the cross sections with radiative corrections （RC） is estimated to be smaller than 0.2%. The Next leading Order （NlO） radiative corrections proportional to α are treated exactly, whereas the all logarithmically enhanced contributions, related to photon jets emitted in the collinear region, are taken into account in frame of the Structure Function approach. Numerous tests of the MCGPJ as well as a detailed comparison with other MC generators are presented.

关键词： luminosity e^+e^- hadrons detectors

Determination of the cellulase activity distribution in Clostridium thermocellum and Caldicellulosiruptor obsidiansis cultures using a fluorescent substrate

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Journal of Environmental Sciences 2015年第8期27卷 212-218页

作者： Jennifer l.Morrell-Falvey James G.Elkins Zhi-Wu Wang Bio Energy Science Center Biosciences Division Oak Ridge National Laboratory The Ohio State University ATI

This study took advantage of resorufin cellobioside as a fluorescent substrate to determine the distribution of cellulase activity in cellulosic biomass fermentation systems. Cellulolytic biofilms were found to express nearly four orders greater cellulase activity compared to planktonic cultures of Clostridium thermocellum and Caldicellulosiruptor obsidiansis, which can be primarily attributed to the high cell concentration and surface attachment. The formation of biofilms results in cellulases being secreted close to their substrates, which appears to be an energetically favorable stategy for insoluble substrate utilization. For the same reason,cellulases should be closely associated with the surfaces of suspended cell in soluble substrate-fed culture, which has been verified with cellobiose-fed cultures of C. thermocellum and C. obsidiansis. This study addressed the importance of cellulase activity distribution in cellulosic biomass fermentation, and provided theoretical foundation for the leading role of biofilm in cellulose degradation. System optimization and reactor designs that promote biofilm formation in cellulosic biomass hydrolysis may promise an improved cellulosic biofuel process.

关键词： Thermophilic Biofilm Cellulose Cellulase Biofuel

Mapping Between Charge-Dyon and Position-Dependent Mass Systems

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Communications in Theoretical Physics 2019年第10期71卷 1261-1266页

作者： Anderson l.de Jesus Alexandre G.M.Schmidt Departamento de Fisica de Volta Redonda Instituto de Ciencias Exatas—Universidade Federal Fluminense

The primary purpose of this work is to reproduce the scenario composed of a charge-dyon system utilizing position-dependent effective mass(PDM) background in the non-relativistic and in the relativistic regimes. In the nonrelativistic case we substitute the exact charge-dyon eigenfunction into PDM Schr?dinger equation, in the Zhu-Kroemer parametrization, and then solve it for the mass distribution considering M = M(r). Analogously, in the relativistic case we study the Klein-Gordon equation for a position-dependent mass, and in this case, we are able to analytically solve the equation for M = M(r, θ).

关键词： position-dependent mass Schrodinger equation Klein-Gordon equation dyon

On/Off-line Prediction Applied to Job Scheduling on Non-Dedicated NOWs

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Journal of Computer Science & Technology 2011年第1期26卷 99-116页

作者： Mauricio Hanzich Porfidio Hernandez Francesc Gine Francesc Solsona Josep l.lerida Department of Computer Application in Science and Engineering Barcelona Supercomputing CenterBarcelonaSpain Department of Computer Architecture & Operating Systems Autonomous University of BarcelonaBarcelonaSpain Department of Computer Science University of LleidaLleidaSpain

This paper proposes a prediction engine designed for non-dedicated clusters, which is able to estimate the turnaround time for parallel applications, even in the presence of serial workload of the workstation owner. The prediction engine can be configured to work with three different estimation kernels： a Historical kernel, a Simulation kernel based on analytical models and an integration of both, named Hybrid kernel. These estimation proposals were integrated into a scheduling system, named CISNE, which can be executed in an on-line or off-line mode. The accuracy of the proposed estimation methods was evaluated in relation to different job scheduling policies in a real and a simulated cluster environment. In both environments, we observed that the Hybrid system gives the best results because it combines the ability of a simulation engine to capture the dynamism of a non-dedicated environment together with the accuracy of the historical methods to estimate the application runtime considering the state of the resources.

关键词： prediction method non-dedicated cluster cluster computing job scheduling simulation

Relationships between Soil Depth and Terrain Attributes in a Semi Arid Hilly Region in Western Iran

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Journal of Mountain Science 2013年第1期10卷 163-172页

作者： Abdolmohammad MEHNATKESH Shamsollah AYOUBI Ahmad JAlAlIAN Kanwar l.SAHRAWAT Department of Soil Science College of AgricultureIsfahanUniversity of Technology International Crop Research Institute for the Semi Arid Tropic(ICRISAT)

Soil depth generally varies in mountainous regions in rather complex *** soil survey methods for evaluating the soil depth in mountainous and hilly regions require a lot of time,effort and consequently relatively large budget to *** study was conducted to explore the relationships between soil depth and topographic attributes in a hilly region in western *** this,one hundred sampling points were selected using randomly stratified methodology,and considering all geomorphic surfaces including summit,shoulder,backslope,footslope and toeslope;and soil depth was actually *** primary and secondary topographic attributes were derived from the digital elevation model(DEM) at the study *** result of multiple linear regression indicated that slope,wetness index,catchment area and sediment transport index,which were included in the model,could explain about 76 % of total variability in soil depth at the selected *** proposed approach may be applicable to other hilly regions in the semi-arid areas at a larger scale.

关键词： Soil depth prediction Topographic attributes Digital elevation model Soil-landscape model