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A Simple Proof of Dieudonn-Manin Classification Theorem

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Acta Mathematica Sinica,English Series 2012年第8期28卷 1553-1574页

作者： Yi wen ding Yi OUYANG Wu wen-Tsun Key Laboratory of Mathematics University of Science and Techonology of ChinaChinese Academy of SciencesHefei 230026P.R.China School of Mathematics University of Science and Technology of ChinaHefei 230026P.R.China

The Dieudonne Manin classification theorem on φ-modules （φ-isocrystals） over a perfect field plays a very important role in p-adic Hodge theory. In this note, in a more general setting we give a new proof of this result, and in the course of the proof, we also give an explicit construction of the Harder Narasimhan filtration of a φ-module.

关键词： φ-Module strict ring Dieudonne Manin theorem Harder-Narasimhan filtration

Financing the price-setting newsvendor with sales effort

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Journal of Management Analytics 2020年第4期7卷 564-590页

作者： wen ding Huihui Song Antai College of Economics&Management Shanghai Jiao Tong UniversityShanghaiPeople’s Republic of China

In this paper,we consider the financing issues in a supply chain where the capitalconstrained retailer should use limited funds to pay for both order and *** retailer decides the retail price,order quantity exante and sales effort expost,and he supports these operational activities by two financing sources:bank loan and trade *** illustrate that in this two-stage problem,the price-setting retailer’s equilibrium sales effort and retail price are both related to the market realization value and the retailer’s cash *** two financing sources are both able to stimulate the retailer to promote *** the retailer’s cash level is reasonably high,both parties(supplier and retailer)benefit from trade *** contrast,if the retailer’s cash level is low,trade credit may discourage the retailer from sales ***,our study shows that the retailer spends more on sales when the market is good than when it is bad.

关键词： Capital-constrained retailer sales effort trade credit bank loan pricesetting

Interception time and uncertainty optimization for tangent-impulse orbit interception problem

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Defence Technology（防务技术） 2022年第3期18卷 418-440页

作者： Yang Hong Li Xin-hong ding wen-zhev Department of Aerospace Science and Technology Space Engineering UniversityNo.1 BaYi RoadHuaiRou DistrictBeijing101416China

The traditional tangent impulse interception problem does not consider the influence of actual ***,by taking the actual state deviation of the interceptor into the orbit design process,an interception orbit that is more robust than the nominal orbit can be ***,we study the minimum time interception problem and the minimum terminal interception error problem under tangent impulse conditions and give an orbit optimization method that considers the interception time and the interception ***,we express the interceptor's transfer time equation as a form of flight path angle,establish a global optimization model for solving the minimum time tangent impulse interception and give a hybrid optimization algorithm based on Augmented Lagrange Genetic Algorithm-Sequential Quadratic Programming(ALGA-SQP).Secondly,we use the universal time equation and Bootstrap resampling technology to calculate the interceptor's terminal error distribution and establish the relevant global optimization model by using the circumscribed cuboid volume of the interceptor's terminal position error ellipsoid as the optimization ***,we combined the above two singleobjective optimization models to establish a global multi-objective optimization model that considers interception time and interception uncertainty and gave a hybrid multi-objective optimization algorithm based on Non-dominated Sorting Genetic Algorithm Ⅱ-Goal Achievement Method(NSGA2-GAM).The simulation example verifies the effectiveness of this method.

关键词： Tangent impulse interception Minimum time Interception uncertainty Multi-objective optimization Hybrid optimization

An evaluation on using soil aggregate stability as the indicator of interrill erodibility

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Journal of Mountain Science 2016年第5期13卷 831-843页

作者： ding wen-feng ZHANG Xun-chang Soil and Water Conservation Department of Yangtze River Scientific Research Institute Wuhan 430010China USDA-ARS Grazinglands Research Lab.7207 W.Cheyenne St.El Reno0K73035USA

Aggregate stability is a very important predictor of soil structure and strength, which influences soil erodibility. Several aggregate stability indices were selected erodibility of four soil properties from temperate for estimating interrill types with contrasting and subtropical regions of China. This study was conducted to investigate how closely the soil interrill erodibility factor in the Water Erosion Prediction Project （WEPP） model relates to soil aggregate stability. The mass fractal dimension （FD）, geometric mean diameter （GMD）, mean weight diameter （MWD）, and aggregate stability index （ASI） of soil aggregates were calculated. A rainfall simulator with a drainable flume （3.0 m long × 1.0 m wide × 0.5 m deep） was used at four slope gradients （5°,10 °,15° and 20°）, and four rainfall intensities （0.6, 1.1, 1.7 and 2.5 mm/min）. Results indicated that the interriU erodibility （Ki） values were significantly correlated to the indices of ASI, MWD, GMD, and FD computed from the aggregate wet-sieve data. The Kihad a strong positive correlation with FD, as well as a strong negative correlation with ASI, GMD, and MWD. Soils with a higher aggregate stability and lower fractal dimension have smaller Ki values. Stable soils were characterized by a high percentage of large aggregates and the erodible soils by a high percentage of smaller aggregates. The correlation coefficients of Ki with ASI and GMD were greater than those with FD and MWD, implying that both the ASI and GMD may be better alternative parameters for empirically predicting the soil Ki factor. ASI and GMD are more reasonable in interrill soil erodibility estimation, compared with Ki calculation in original WEPP model equation. Results demonstrate the validation of soil aggregation characterization as an appropriate indicator of soil susceptibility to erosion in contrasting soil types in China.

关键词： Soil erodibility Interrill Aggregate stability Soil erosion

Two new tetralone derivatives from the culture of Xylaria hypoxylon AT-028

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Chinese Chemical Letters 2008年第11期19卷 1323-1326页

作者： wen Gu Hui ding Department of Forestry Chemieal Engineering School of Chemical Engineering Nanjing Forestry University Nanjing 210037 China

Two new tetralone derivatives named xylariol A （1） and B （2） were isolated from the EtOAc extract of the culture broth of Xylaria hypoxylon AT-028 （Xylariaceae）, and their structures were elucidated by MS, 1R, 1D- and 2D-NMR spectra, and by X-ray diffraction analysis. 1 and 2 showed moderate cytotoxic activities against Hep G2 cells in the in vitro cytotoxic assay with IC50 values of 22.3 and 21.2 μg/mL, respectively.

关键词： Xylaria hvpoxylon Xylariol A Xylariol B Cylotoxicity

Numerical studies of high-dimensional nonlinear viscous and nonviscous wave equations by using finite difference methods

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International Journal of Modeling, Simulation, and Scientific Computing 2020年第2期11卷 1-30页

作者： ding-wen Deng Zhu-An Wang College of Mathematics and Information Science Nanchang Hangkong University Nanchang 330063P.R.China

The numerical solutions of two-dimensional(2D)and three-dimensional(3D)nonlinear viscous and nonviscous wave equations via the unified alternating direction implicit(ADI)finite difference methods(FDMs)are obtained in this *** making use of the discrete energy method,it is proven that their numerical solutions converge to exact solutions with an order of two in both time and space with respect to H^(1)-*** results confirm that they are relatively accurate and high-resolution,and more successfully simulate the conservation of the energy for nonviscous equations,and the dissipation of the energy for viscous equation.

关键词： Viscous and nonviscous wave equations FDMs ADI methods convergence

Regional Variation in Carbon Sequestration Potential of Forest Ecosystems in China

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Chinese Geographical Science 2017年第3期27卷 337-350页

作者： XU Li wen ding ZHU Jianxing HE Nianpeng Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of ScienceBeijing 100101China University of Chinese Academy of Sciences Beo'ing 10049China

Enhancing forest carbon(C) storage is recognized as one of the most economic and green approaches to offsetting anthropogenic CO_2 emissions. However, experimental evidence for C sequestration potential(C_(sp)) in China's forest ecosystems and its spatial patterns remain unclear, although a deep understanding is essential for policy-makers making decisions on reforestation. Here, we surveyed the literature from 2004 to 2014 to obtain C density data on forest ecosystems in China and used mature forests as a reference to explore C_(sp). The results showed that the C densities of vegetation and soil(0–100 cm) in China's forest ecosystems were about 69.23 Mg C/ha and 116.52 Mg C/ha, respectively. In mature forests, the C_(sp) of vegetation and soil are expected to increase to 129.26 Mg C/ha(87.1%) and 154.39 Mg C/ha(32.4%) in the coming decades, respectively. Moreover, the potential increase of C storage in vegetation(10.81 Pg C) is estimated at approximately twice that of soil(5.01 Pg C). Higher C_(sp) may occur in the subtropical humid regions and policy-makers should pay particular attention to the development of new reforestation strategies for these areas. In addition to soil nutrients and environment, climate was an important factor influencing the spatial patterns of C density in forest ecosystems in China. Interestingly, climate influenced the spatial patterns of vegetation and soil C density via different routes, having a positive effect on vegetation C density and a negative effect on soil C density. This estimation of the potential for increasing forest C storage provided new insights into the vital roles of China's forest ecosystems in future C sequestration. More importantly, our findings emphasize that climate constraints on forest C sequestration should be considered in reforestation strategies in China because the effects of climate were the opposite for spatial patterns of C density in vegetation and *** forest carbon(C) storage is recognized

关键词： carbon density forest reforestation storage sequestration potential

The snowline in the protoplanetary disk and extrasolar planets

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Research in Astronomy and Astrophysics 2017年第8期17卷 13-22页

作者： Chun-Jian Liu Zhen Yao wen-Bo ding College of Mathematics and Physics Bohai University College of Science Liaoning University of Technology

We investigate the behavior of the snowline in a protoplanetary disk and the relationship between the radius of the snowline and properties of molecular cloud *** our disk model,we consider mass influx from the gravitational collapse of a molecular cloud core,irradiation from the central star,and thermal radiation from the ambient molecular cloud *** the protoplanetary disk evolves,the radius of the snowline increases first to a maximum value Rmax,and then decreases in the late stage of evolution of the protoplanetary *** value of Rmaxis dependent on the properties of molecular cloud cores(mass M;,angular velocity ω and temperature T;).Many previous works found that solid material tends to accumulate at the location of the snowline,which suggests that the snowline is the preferred location for giant planet *** these conclusions,we compare the values of R;with semimajor axes of giant planets in extrasolar systems,and find that Rmaxmay provide an upper limit for the locations of the formation of giant planets which are formed by the core accretion model.

关键词： snowline—planets and satellites formation—protoplanetary disks

On social computing research collaboration patterns： a social network perspective

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Frontiers of Computer Science 2012年第1期6卷 122-130页

作者： Tao WANG Qingpeng ZHANG Zhong LIU wenli LIU ding wen Science and Technology on Information Systems Engineering Lab College of Information Systems and ManagementNational University of Defense and TechnologyChangsha 410073China Department of Systems and Industrial Engineering University of ArizonaTucsonAZ 85721USA Military Computational Experiments and Parallel Systems Research Center National University of Defense and TechnologyChangsha 410073China

The field of social computing emerged more than ten years ago. During the last decade, researchers from a vari- ety of disciplines have been closely collaborating to boost the growth of social computing research. This paper aims at iden- tifying key researchers and institutions, and examining the collaboration patterns in the field. We employ co-authorship network analysis at different levels to study the bibliographic information of 6 543 publications in social computing from 1998 to 2011. This paper gives a snapshot of the current re- search in social computing and can provide an initial guid- ance to new researchers in social computing.

关键词： social computing bibliographic analysis com-putational social science social network analysis