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Optimal design of culling compensation policy under the African swine fever——Based on simulations of typical pig farms in China

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Journal of Integrative Agriculture 2023年第2期22卷 611-622页

作者： GUO Shi-juan lü xin-ye HU Xiang-dong Institute of Agricultural Economics and Development Chinese Academy of Agricultural SciencesBeijing 100081P.R.China Institute of Agricultural Information and Economy Shandong Academy of Agricultural SciencesJinan 250000P.R.China

This paper aims to optimize the culling compensation policy from a micro perspective through scenario *** on an investigation of 273 pig farms in eight regions,four typical pig farms were constructed according to farm size and breeding mode,representing the swine producers in ***,a decision objective function of pig farms facing suspected African swine fever(ASF)outbreaks was *** study used a mathematical programming model to design and simulate scenarios based on compensation standards and local implementation levels,aiming to incentivize pig farms to report *** results show that the optimal decisions on epidemic reports differed among typical farms and by herd daily *** results suggest the following adjustments for optimizing culling compensation policies:(1)to set culling compensation standards based on the market value and(2)to maintain a high level of epidemic surveillance capability in the animal husbandry and veterinary sector.

关键词： culling compensation African swine fever epidemic report mathematical programming model

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超级稻农业技术推广到位效率分析

中国农业科学 2011年第24期44卷 5124-5129页

作者：吕新业朱晓莉周宏中国农业科学院农业经济与发展研究所南京农业大学理学院南京农业大学经济管理学院

【目的】从投入产出角度分析超级稻种植过程中各生产环节的技术推广到位效率。【方法】通过对超级稻种植环节的分解,确立农业技术推广到位效率的关键指标,借助于超效率DEA方法对获取的第一手田间数据进行分析处理。【结果】超级稻示范... 详细信息

【目的】从投入产出角度分析超级稻种植过程中各生产环节的技术推广到位效率。【方法】通过对超级稻种植环节的分解,确立农业技术推广到位效率的关键指标,借助于超效率DEA方法对获取的第一手田间数据进行分析处理。【结果】超级稻示范户水稻生产效率都有效,非示范户的生产效率平均仅有80%;3个时间偏差指标对产量的总影响占15%;通过松弛变量分析,对于非有效指标的离差程度进行了分析和定量说明。【结论】超级稻推广环节的到位情况对超级稻的产量和效率有重要影响,研究充分说明农业技术推广的效率在种植管理中不仅影响到产量,也影响到种植成本。

关键词：超效率DEA 推广效率超级稻技术推广

Simplified theoretical analysis and numerical study on the dynamic behavior of FCP under blast loads

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Frontiers of Structural and Civil Engineering 2020年第4期14卷 983-997页

作者： Chunfeng ZHAO xin ye Avinash GAUTAM xin lU YlMO Anhui Key laboratory of Civil Engineering Structures and Materials Hefei University of TechnologyHefei 230009China State Key laboratory of Structural Analysis for Industrial Equipment Dalian University of TechnologyDalian 116024.China School of Civil Engineering Hefei University of TechnologyHefei 230009China Deparment of Civil and Environmental Enginering University of HoustonHoustonTX 77024USA

Precast concrete structures have developed rapidly in the last decades due to the advantages of better quality,non-pollution and fast construction with respect to conventional cast-in-place *** the present study,a theoretical model and nonlinear 3D model are developed and established to assess the dynamic behavior of precast concrete slabs under blast *** first,the 3D model is validated by an experiment performed by other *** verified model is adopted to investigate the blast performance of fabricated concrete panels(FCPs)in terms of parameters of the explosive charge,panel thickness,and reinforcement ***,a simplified theoretical model of the FCP under blast load is developed to predict the maximum *** is indicated that the theoretical model can precisely predict the maximum displacement of FCP under blast *** results show that the failure modes of the panels varied from bending failure to shear failure with the mass of TNT *** thickness of the panel,reinforcement ratio,and explosive charges have significant effects on the anti-blast capacity of the FCPs.

关键词： precast structure fabricated concrete panel blast resistance theory model empirical equation

lower Bound for Quantum Integration Error on Anisotropic Sobolev Classes

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Acta Mathematica Sinica,English Series 2010年第4期26卷 669-678页

作者： Pei xin ye School of Mathematical Sciences and lPMC Nankai University Tianjin 300071 P. R. China

We study the approximation of the integration of multivariate functions in the quantum model of computation. Using a new reduction approach we obtain a lower bound of the n-th minimal query error on anisotropic Sobolev class R（Wpr（[0, 1]d））（r R＋d）. Then combining this result with our previous one we determine the optimal bound of n-th minimal query error for anisotropic Hblder- Nikolskii class R（H∞r（[0,1]d）） and Sobolev class R（W∞r（[0,1]d））. The results show that for these two types of classes the quantum algorithms give significant speed up over classical deterministic and randomized algorithms.

关键词： quantum integration anisotropic Sobolev classes Holder-Nikolskii classes n-th minimal query error

Synthesis of Iminosugar-Containing KRN7000 Analogues

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Chinese Journal of Chemistry 2017年第6期35卷 1001-1008页

作者： leiZhang xin-Shan ye State Key laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University Xue Yuan Road No. 38 Beijing 100191 China

Three new iminosugar-containing KRN7000 （also referred to as α-GalCer） analogues were designed and syn- thesized. In the design, the galactose moiety of KRN7000 was replaced by iminosugars and the iminosugar struc- tures were connected with ceramide in different manners with a C-glycosidic bond instead of the O-glycosidic bond. To our knowledge, this is the first report in which iminosugars are incorporated in KRN7000 structure modifica- tions. The synthetic compounds were evaluated for their ability to stimulate cytokine release. The results may benefit better understanding of structure-activity relationships and facilitate future design of more KRNT000 derivatives.

关键词： KRN7000 analogue glycolipid a-GalCer iminosugar synthesis

Donor Preactivation-Based Glycosylation:An Efficient Strategy for Glycan Synthesis

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Chinese Journal of Chemistry 2021年第3期39卷 531-542页

作者： Xianjin Qin xin-Shan ye State Key laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityXue Yuan Road No.38Beijing 100191China

Carbohydrates have gained a lot of appreciation in the past few decades due to their important roles in numerous biological *** a structurally well-defined carbohydrate compound is essential for the understanding of its *** some innovative methods have been developed for the synthesis of complex oligosaccharides,glycan synthesis is in general still a time-consuming and difficult ***,we will introduce the preactivation-based glycosylation strategy,which is an efficient protocol independent of the reactivity of glycosyl *** review will focus on summarizing the versatile applications of preactivation strategy in stereoselective glycosylation and one-pot assembly of biologically important oligosaccharides and even polysaccharides。

关键词： Preactivation Chemoselectivity Glycosylation Carbohydrates Solvent effect Oligosaccharide synthesis

Hazard Model with Random Treatment Time-lag Effect

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Acta Mathematica Sinica,English Series 2023年第9期39卷 1755-1767页

作者： xin ye Yan Yan liu School of Mathematics and Statistics Wuhan UniversityWuhan430072P.R.China

In clinical studies,it is often that the medical treatments take a period of time before having an effect on patients and the delayed time may vary from person to *** though there exists a rich literature developing methods to estimate the time-lag period and treatment effects after lag time,most of these existing studies assume a fixed lag *** this paper,we propose a hazard model incorporating a random treatment time-lag effect to describe the heterogeneous treatment effect among *** EM algorithm is used to obtain the maximum likelihood *** give the asymptotic properties of the proposed estimator and evaluate its performance via simulation *** application of the proposed method to real data is provided.

关键词： Random lag time treatment effect right censored data EM algorithm

When aggregation-induced emission meets protein aggregates

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National Science Review 2021年第6期8卷 13-15页

作者： Sicheng Tang Songtao ye xin Zhang Department of Chemistry The Pennsylvania State University Department of Biochemistry and Molecular Biology The Pennsylvania State University

Protein misfolding and aggregation have been associated with a number of human diseases. As a multistep process(Fig. 1 a), protein unfolding yields misfolded intermediates as either monomers or oligomers, which evolve into insoluble aggregates as amorphous aggregates or amyloid-β fibrils. Detection of protein aggregates is of great interest as it could generate unprecedented insights into biogenesis, regulation and pathology of protein aggregation.

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SDGNN: Symmetry-Preserving Dual-Stream Graph Neural Networks

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1717-1719页

作者： Jiufang Chen ye Yuan xin luo the College of Computer Science and Technology Chongqing University of Posts and TelecommunicationsChongqing 400065 the Chongqing Key laboratory of Big Data and Intelligent Computing Chongqing Institute of Green and Intelligent TechnologyChinese Academy of SciencesChongqing 400714China the College of Computer and Information Science Southwest UniversityChongqing 400715China IEEE

Dear Editor,This letter proposes a symmetry-preserving dual-stream graph neural network(SDGNN) for precise representation learning to an undirected weighted graph(UWG). Although existing graph neural networks(GNNs) are influential instruments for representation learning to a UWG, they invariably adopt a unique node feature matrix for illustrating the sole node set of a UWG.

关键词： representation preserving undirected