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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

The intricacies of neurotrophic factor therapy for retinal ganglion cell rescue in glaucoma: a case for gene therapy

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Neural Regeneration Research 2016年第6期11卷 875-877页

作者： Marianna Foldvari ding wen Chen School of Pharmacy Waterloo Institute of Nanotechnology and Center for Bioengineering and Biotechnology University of Waterloo

Regeneration of damaged retinal ganglion cells（RGC） and their axons is an important aspect of reversing vision loss in glaucoma patients. While current therapies can effectively lower intraocular pressure, they do not provide extrinsic support to RGCs to actively aid in their protection and regeneration. The unmet need could be addressed by neurotrophic factor gene therapy, where plasmid DNA, encoding neurotrophic factors, is delivered to retinal cells to maintain sufficient levels of neurotrophins in the retina. In this review, we aim to describe the intricacies in the design of the therapy including： the choice of neurotrophic factor, the site and route of administration and target cell populations for gene delivery. Furthermore, we also discuss the challenges currently being faced in RGC-related therapy development with special considerations to the existence of multiple RGC subtypes and the lack of efficient and representative in vitro models for rapid and reliable screening in the drug development process.

关键词： neurotrophic glaucoma ganglion RGCs retina intraocular Regeneration administration representative populations

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

Reproduced Giant Localization Length of Two-Side Surface Disordered Nanowires with Long-Range Correlation

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Chinese Physics Letters 2011年第10期28卷 184-187页

作者： ZHAO Wei ding Jian-wen Department of Physics&Institute for Nanophysics and Rare-earth Luminescence Xiangtan UniversityXiangtan 411105

We numerically investigate the normalized localization length of two-side rough nanowires as functions of energy,magnetic field and correlation strength by using modular recursive Green's function *** is found that in the absence of correlation,while in the presence of magnetic field,the localization length increases linearly for two-side roughness,which is different to diverging exponentially for one-side ***,the localization of electrons is suppressed in the low energy region,but enhanced in the high energy *** the presence of correlation,especially,an exponential enhancement in the localization length resumes in high energy region,in contrast to that in low energy region,the long-range correlations abnormally enhance the localization of electrons.A competitive mechanism is proposed to explain this behavior.

关键词： nanowires roughness resume

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

Research on the intelligent design system for investment casting die of aero-engine turbine blade based on knowledge

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航空动力学报 2010年第5期25卷 1061-1067页

作者： JIANG Rui-song ZHANG ding-hua WANG wen-hu The Key Laboratory of Contemporary Design and Integrated Manufacturing Ministry of EducationSchool of Mechanical EngineeringNorthwestern Polytechnical UniversityXi'an 710072China

To solve the problems in turbine blade investment casting die design process such as long design time,lacking of expert experience and low level of intelligence,knowledge-based engineering (KBE) was introduced in the turbine blade investment casting die design field. The key technologies of the intelligent design method were researched and a prototype system was developed. A hybrid reasoning model was prompted in which case-based reasoning (CBR) was applied to conceptual design and rule-based reasoning (RBR) was applied to parts design after research the design process and domain knowledge of casting die. In the conceptual design stage,a retrieval model which integrated nearest neighbor approach and knowledge-based retrieval approach was prompted to improve the retrieval efficiency. Meanwhile,RBR was used to modify the retrieval result. The practical application results indicate that this system can reuse the expert experience efficiently and heighten the die design efficiency and quality.

关键词： turbine blade investment casting die intelligent design knowledge-based engineering (KBE)

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