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Plant Phenotyping:Past,Present,and Future

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Plant Phenomics 2019年第1期1卷 179-184页

作者： roland Pieruschka Uli Schurr IBG-2 Plant Sciences Forschungszentrum Julich GmbHD-52425 ulichGermany

A plant develops the dynamic phenotypes from the interaction of the plant with the *** these processes that span plant’s lifetime in a permanently changing environment is essential for the advancement of basic plant science and its translation into application including breeding and crop *** plant research community was thus confronted with the need to accurately measure diverse traits of an increasingly large number of plants to help plants to adapt to resource-limiting environment and low-input *** this overview,we outline the development of plant phenotyping as a multidisciplinary *** sketch the technological advancement that laid the foundation for the development of phenotyping centers and evaluate the upcoming challenges for further advancement of plant phenotyping specifically with respect to standardization of data acquisition and ***,we describe the development of the plant phenotyping community as an essential step to integrate the community and effectively use the emerging synergies.

关键词： Plant breeding sketch

topic evolution based on the probabilistic topic model： a review

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Frontiers of Computer Science 2017年第5期11卷 786-802页

作者： Houkui ZHOU Huimin YU roland HU College of Information Science & Electronic Engineering Zhejiang University Hangzhou 310027 China State Key Laboratory of CAD & CG Hangzhou 310027 China School of Information Engineering Zhejiang A&F University Hangzhou 311300 China Zhejiang Provincial Key Laboratory of Forestry Intelligent Monitoring and Information technology Hangzhou 311300 China

Accurately representing the quantity and characteristics of users＇ interest in certain topics is an important problem facing topic evolution researchers, particularly as it applies to modem online environments. Search engines can provide information retrieval for a specified topic from archived data, but fail to reflect changes in interest toward the topic over time in a structured way. this paper reviews notable research on topic evolution based on the probabilistic topic model from multiple aspects over the past decade. First, we introduce notations, terminology, and the basic topic model explored in the survey, then we summarize three categories of topic evolution based on the probabilistic topic model： the discrete time topic evolution model, the continuous time topic evolution model, and the online topic evolution model. Next, we describe applications of the topic evolution model and attempt to summarize model generalization performance evaluation and topic evolution evaluation methods, as well as providing comparative experimental results for different models. to conclude the review, we pose some open questions and discuss possible future research directions.

关键词： topic evolution probabilistic topic models text corpora evaluation method

A NEW APPROACH AND ERROR ANALYSIS FOR RECONStRUCtING tHE SCAttERED WAVE BY tHE POINt SOURCE MEtHOD

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Journal of Computational Mathematics 2007年第2期25卷 113-130页

作者： Jijun Liu Gen Nakamura roland Potthast Department of Mathematics Southeast University Nanjing 210096 China Department of Mathematics Graduate School of Science Hokkaido University Sapporo 060-0810 Japan Institute for Numerical and Applied Mathematics University of Gottingen Lotzestr 16-1837085 Gottingen Germany

Consider an inverse scattering problem by an obstacle D belong to R^2 with impedance boundary. We investigate the reconstruction of the scattered field u^s from its far field pattern u^∞ using the point source method. First, by applying the boundary integral equation method, we provide a new approach to the point-source method of Potthast by classical potential theory. this extends the range of the point source method from plane waves to scattering of arbitrary waves. Second, by analyzing the behavior of the Hankel function, we obtain an improved strategy for the choice of the regularizing parameter from which an improved convergence rate （compared to the result of [15]） is achieved for the reconstruc- tion of the scattered wave. third, numerical implementations are given to test the validity and stability of the inversion method for the impedance obstacle.

关键词： Inverse scattering Regularization Error estimate Numerics

towards social behavior in virtual-agent navigation

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Science China(Information Sciences) 2016年第11期59卷 16-32页

作者： Angelos KREMYZAS Norman JAKLIN roland GERAERtS Department of Information and Computing Sciences Utrecht University

We present Social Groups and Navigation(SGN), a method to simulate the walking behavior of small pedestrian groups in virtual environments. SGN is the first method to simulate group behavior on both global and local levels of an underlying planning hierarchy. We define quantitative metrics to measure the coherence and the sociality of a group based on existing empirical data of real crowds. SGN does not explicitly model coherent and social formations, but it lets such formations emerge from simple geometric rules. In addition to a previous version, SGN also handles group-splitting to smaller groups throughout navigation as well as social sub-group behavior whenever a group has to temporarily split up to re-establish its coherence. For groups of four, SGN generates between 13% and 53% more socially-friendly behavior than previous methods, measured over the lifetime of a group in the simulation. For groups of three, the gain is between 15% and 31%, and for groups of two, the gain is between 1% and 4%. SGN is designed in a flexible way, and it can be integrated into any crowd-simulation framework that handles global path planning and any path following as separate *** show that SGN enables the simulation of thousands of agents in real time.

关键词： virtual humans social-group behavior autonomous agent navigation crowd simulation

Industrial Experience with Case Hardening of Stainless Steels by Solution Nitriding

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材料热处理学报 2004年第5期25卷 354-359页

作者： Hans Berns Bernd Edenhofer roland Zaugg Ruhr University Materials Technology D-44780 Bochum GermanyIPSEN Industries International GmbH D-47514 Kleve GermanyHdrterei GersterA.G. CH-4622 Egerkingen Switzerland

SolNit(R) is a novel heat treatment to case harden stainless steels with nitrogen instead of carbon. the calculated equilibrium pressure of N2 corresponds well with the nitrogen content in the steel surface. the process is carried out in vacuum furnaces with pressurized gas quenching. Numerous parts of different stainless steels have been successfully SolNit(R) treated in industry leading to superior properties in respect to hardness/strength and corrosion

关键词：不锈钢渗氮表面硬化热处理

Managing the Limbe Floods:Considerations for Disaster Risk Reduction in Cameroon

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International Journal of Disaster Risk Science 2014年第2期5卷 147-156页

作者： roland Ndille Johannes A.Belle Faculty of Arts University of BueaP.O.Box 63BueaSWRCameroon Disaster Management training and Education Centre for Africa University of the Free StateBloemfontein 9300South Africa

Cameroon has recorded disasters, both natural and man-made, in the past. the coastal city of Limbe and many other geographical locations are potential sites for future disasters. On the basis of interviews and related primary and secondary literature, this article looks at past occurrences of floods in Limbe, particularly those of 2001,and how the state and local authorities managed the challenge. through this, it attempts an evaluation of state policies and the institutional structure for disaster risk reduction(DRR) and management in the country. the study reveals that Cameroon does not have a national disaster management structure and a national platform for DRR. Disaster related activities are lumped together with other civil protection responsibilities of the Ministry of territorial Administration and Decentralization(MINAtD) despite the country’s commitment to the Hyogo Framework for Action 2005–2015. Government interventions are more reactive than proactive although its strategy to disaster management indicates both disaster preparedness and emergency intervention and rehabilitation. the study concludes that the present strategy is bureaucratic,financially burdensome, and does not really achieve the essential goals of DRR in saving lives and reducing vulnerability. For DRR to be effective in Cameroon, a permanent disaster management unit with regional and local structures should be put in place independent of other branches of the Department of Disaster and Emergency Services of MINAtD and with each level exercising a significant degree of operative autonomy. A national policy and framework with emphasis on DRR should be adopted in the country.

关键词： disaster floods Flood

tree species diversity and utilities in a contracting lowland hillside rainforest fragment in Central Vietnam

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Forest Ecosystems 2017年第3期4卷 182-200页

作者： Yen thi Van roland Cochard Hue University of Agriculture and Forestry Hue University Institute of Integrative Biology Swiss Federal Institute of Technology

Background： Within the highly bio-diverse ‘Northern Vietnam Lowland Rain Forests Ecoregion＇ only small, and mostly highly modified forestlands persist within vast exotic-species plantations. the aim of this study was to elucidate vegetation patterns of a secondary hillside rainforest remnant（elevation 120–330 m, 76 ha） as an outcome of natural processes, and anthropogenic processes linked to changing forest ***： In the rainforest remnant tree species and various bio-physical parameters（relating to soils and terrain）were surveyed on forty 20 m × 20 m sized plots. the forest＇s vegetation patterns and tree diversity were analysed using dendrograms, canonical correspondence analysis, and other statistical ***： Forest tree species richness was high（172 in the survey, 94 per hectare）, including many endemic species（〉16%; some recently described）. Vegetation patterns and diversity were largely explained by topography, with colline/sub-montane species present mainly along hillside ridges, and lowland/humid-tropical species predominant on lower slopes. Scarcity of high-value timber species reflected past logging, whereas abundance of light-demanding species, and species valued for fruits, provided evidence of human-aided forest restoration and ‘enrichment＇ in terms of useful trees. Exhaustion of sought-after forest products, and decreasing appreciation of non-wood products concurred with further encroachment of exotic plantations in between 2010 and 2015. Regeneration of rare tree species was reduced probably due to forest ***： Despite long-term anthropogenic influences, remnant forests in the lowlands of Vietnam can harbor high plant biodiversity, including many endangered species. Various successive future changes（vanishing species, generalist dominance, and associated forest structural-qualitative changes） are, however, expected to occur in smal forest *** forest biodiversity can only be maintained if forest fragments m

关键词： Secondary evergreen monsoon forest Floristic patterns tree species richness timber NtFP Biodiversity conservation

A DLM/FD/IB Method for Simulating Cell/Cell and Cell/Particle Interaction in Microchannels

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Chinese Annals of Mathematics,Series B 2010年第6期31卷 975-990页

作者： tsorng-Whay PAN roland GLOWINSKI Department of Mathematics University of Houston

A spring model is used to simulate the skeleton structure of the red blood cell (RBC) membrane and to study the red blood cell (RBC) rheology in Poiseuille flow with an immersed boundary method. the lateral migration properties of many cells in Poiseuille flow have been investigated. the authors also combine the above methodology with a distributed Lagrange multiplier/fictitious domain method to simulate the interaction of cells and neutrally buoyant particles in a microchannel for studying the margination of particles.

关键词： Red blood cells Elastic spring model Margination Fictitious domain method Immersed boundary method Microchannel

ON SOURCE ANALYSIS BY WAVE SPLIttING WItH APPLICAtIONS IN INVERSE SCAttERING OF MULtIPLE OBStACLES

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Journal of Computational Mathematics 2007年第3期25卷 266-281页

作者： Fahmi ben Hassen Jijun Liu roland Potthast Laboratoire de Modelisation Mathematique et Numerique dans les Sciences de l'Ingenieur ENIT-University of Tunis-El Manar BP 37 1002 Tunis Tunisia Department of Mathematics Southeast University Nanjing 210096 China University of Reading Department of Mathematics Whiteknights PO Box 220 Berkshire RG6 6AX UK

We study wave splitting procedures for acoustic or electromagnetic scattering problems. the idea of these procedures is to split some scattered field into a sum of fields coming from different spatial regions such that this information can be used either for inversion algo- rithms or for active noise control. Splitting algorithms can be based on general boundary layer potential representation or Green＇s representation formula. We will prove the unique decomposition of scattered wave outside the specified reference domain G and the unique decomposition of far-field pattern with respect to different reference domain G. Further, we employ the splitting technique for field reconstruction for a scatterer with two or more separate components, by combining it with the point source method for wave recovery. Us-ing the decomposition of scattered wave as well as its far-field pattern, the wave splitting procedure proposed in this paper gives an efficient way to the computation of scattered wave near the obstacle, from which the multiple obstacles which cause the far-field pattern can be reconstructed separately. this considerably extends the range of the decomposition methods in the area of inverse scattering. Finally, we will provide numerical examples to demonstrate the feasibility of the splitting method.

关键词： Inverse scattering Wave splitting Potential theory Near field Regularization.