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AN INTEGRO-DIFFERENTIAL PARABOLIC VARIATIONAL INEQUALITY ARISING FROM THE VALUATION OF DOUBLE BARRIER AMERICAN OPTION

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Journal of Systems Science & Complexity 2014年第2期27卷 276-288页

作者： SUN Yudong SHI Yimin gu xin Department of Applied Mathematics Northwestern Polytechnical University Department of Methodology and Statistics Utrecht University

This paper studies the nonlinear variational inequality with integro-differential term arising from valuation of American style double barrier option. First, the authors use the penalty method to transform the variational inequality into a nonlinear parabolic initial boundary problem(i.e., penalty problem). Second, the existence and uniqueness of solution to the penalty problem are proved by using the Scheafer fixed point theory. Third, the authors prove the existence of variational inequality' solution by showing the fact that the penalized PDE converges to the variational inequality. The uniqueness of solution to the variational inequality is also proved by contradiction.

关键词： American style barrier option existence integro-differential uniqueness variational inequality.

Factors Influencing Glucoraphanin and Sulforaphane Formation in Brassica Plants:A Review

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Journal of Integrative Agriculture 2012年第11期11卷 1804-1816页

作者： gu Zhen-xin guO Qiang-hui gu Ying-juan College of Food Science and Technology Nanjing Agricultural University Nanjing 210095 P.R.China

Sulforaphane is a type of sulfur-containing isothiocyanates hydrolyzed from glucosinolates by myrosinase found in Brassica plants. Sulforaphane is a naturally occurring inducer of phase II enzymes in human and animal bodies to detoxify cancer-causing chemicals. Glucoraphanin is the precursor of sulforaphane and its content is greatly influenced by plant species and genotype, plant organs, pre-harvest factors, and post-harvest processing, thus sulforaphane formation is also directly influenced. Here, we review the formation mechanism of sulforaphane and the factors influencing sulforaphane formation. In the end, the future directions are also discussed.

关键词： Brassica plant glucosinolate sulforaphane glucoraphanin influencing factor

Bond-associated non-ordinary state-based peridynamic model for multiple spalling simulation of concrete

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Acta Mechanica Sinica 2021年第7期37卷 1104-1135,I0002页

作者： Siyang Yang xin gu Qing Zhang Xiaozhou Xia Department of Engineering Mechanics College of Mechanics and MaterialsHohai UniversityNanjing 211100China

The non-ordinary state-based peridynamic(NOSB PD)model has the capability of incorporating existing constitutive relationships in the classical continuum *** the present work,we first develop an NOSB PD model corresponding to the Johnson–Holmquist II(JH-2)constitutive damage model,which can describe the severe damage of concrete under intense impact ***,the numerical oscillation problem of the NOSB PD caused by zero-energy mode is analyzed and hence a bond-associated non-ordinary state-based peridynamic(BA-NOSB PD)model is adopted to remove the ***,the elastic deformation of a three-dimensional bar is analyzed to verify the capability of BA-NOSB PD in eliminating the numerical ***,concrete spalling caused by the interaction of incident compression wave and reflected tension wave is *** dynamic tensile fracture process of concrete multiple spalling is accurately reproduced for several examples according to the spalling number and spalling thickness analysis,illustrating the approach can well simulate and analyze the concrete spalling discontinuities.

关键词： Non-ordinary state-based peridynamics Bond-associated horizon-Johnson-HolmquistⅡ(JH-2)model Wave propagation Multiple spalling

A Coupled Thermomechanical Crack Propagation Behavior of Brittle Materials by Peridynamic Differential Operator

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 339-361页

作者： Tianyi Li xin gu Qing Zhang College of Architectural Engineering Jiangsu Open UniversityNanjing210036China Department of Engineering Mechanics Hohai UniversityNanjing211100China

This study proposes a comprehensive,coupled thermomechanical model that replaces local spatial derivatives in classical differential thermomechanical equations with nonlocal integral forms derived from the peridynamic differential operator(PDDO),eliminating the need for calibration *** model employs a multi-rate explicit time integration scheme to handle varying time scales in multi-physics *** simulations conducted on granite and ceramic materials,this model demonstrates its *** successfully simulates thermal damage behavior in granite arising from incompatible mineral expansion and accurately calculates thermal crack propagation in ceramic slabs during *** account for material heterogeneity,the model utilizes the Shuffle algorithm andWeibull distribution,yielding results that align with numerical simulations and experimental *** coupled thermomechanical model shows great promise for analyzing intricate thermomechanical phenomena in brittle materials.

关键词： Peridynamic differential operator thermomechanical coupling heterogeneity numerical simulation

Dm-KDE： dynamical kernel density estimation by sequences of KDE estimators with fixed number of components over data streams

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Frontiers of Computer Science 2014年第4期8卷 563-580页

作者： Min XU Hisao ISHIBUCHI xin gu Shitong WANG School of Digital Media Jiangnan University Wuxi 214122 China School of Internet of Things Technology Wuxi Institute of Technology Wuxi 214121 China Department of Computer Science Osaka Prefecture University Osaka 599-8531 Japan

In many data stream mining applications, traditional density estimation methods such as kemel density estimation, reduced set density estimation can not be applied to the density estimation of data streams because of their high computational burden, processing time and intensive memory allocation requirement. In order to reduce the time and space complexity, a novel density estimation method Dm-KDE over data streams based on the proposed algorithm m-KDE which can be used to design a KDE estimator with the fixed number of kernel components for a dataset is proposed. In this method, Dm-KDE sequence entries are created by algorithm m-KDE instead of all kemels obtained from other density estimation methods. In order to further reduce the storage space, Dm-KDE sequence entries can be merged by calculating their KL divergences. Finally, the probability density functions over arbitrary time or entire time can be estimated through the obtained estimation model. In contrast to the state-of-the-art algorithm SOMKE, the distinctive advantage of the proposed algorithm Dm-KDE exists in that it can achieve the same accuracy with much less fixed number of kernel components such that it is suitable for the scenarios where higher on-line computation about the kernel density estimation over data streams is required. We compare Dm-KDE with SOMKE and M-kernel in terms of density estimation accuracy and running time for various stationary datasets. We also apply Dm-KDE to evolving data streams. Experimental results illustrate the effectiveness of the pro- posed method.

关键词： kernel density estimation Kullback-Leibler di- vergence data streams kernel width time and space complexity

Design of Quenching Process for Large-sized AISI P20 Steel Block Used as Plastic Die

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Journal of Materials Science & Technology 2006年第1期22卷 139-144页

作者： Dongli SONG Jianfeng gu Jiansheng PAN xin YAO Key Laboratory of the Ministry of Education of High Temperature Materials and Testing Shanghai Jiao Tong UniversityShanghai 200030 China

For large-sized AISI P20 steel block used as plastic die with a thickness of more than 200 mm, appropriate quenching processes are the key to obtain much thick hardened layer. In this paper, different quenching processes of AISI P20 steel block such as oil quenching, direct water quenching, water quenching with precooling and water quenching with pre-cooling and self-tempering were numerically investigated by computer simulation based on the detailed discussion on the mathematical models of quenching processes including partial differential equations of heat transfer, thermal physical properties, latent heat, heat transfer coefficient and calculation of phase transformation, The results show that the water quenching with pre-cooling and self-tempering process can not only effectively avoid quenching cracks, but also obtain deeper harden depth than oil quenching.

关键词： Computer simulation Quenching process AISI P20 steel Plastic die

First Enantioselective Synthesis of Isoamericanol A and Isoamericanin A

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Chinese Chemical Letters 2001年第6期12卷 485-486页

作者： Wen xin gu An xin WU Xue Gong SHE xin Fu PAN Department of Chemistry National Laboratory of Applied Organic ChemistryLanzhou UniversityLanzhou 730000

The first enantioselective synthesis approach to two chiral 1,4-benzodioxane neolignans isoamericanol A and isoamericanin A was reported.

关键词： Enantioselective synthesis 1 4-benzodioxane neolignans

Efficient stochastic analysis of unsaturated slopes subjected to various rainfall intensities and patterns

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Geoscience Frontiers 2023年第1期14卷 346-359页

作者： xin gu Lin Wang Qiang Ou Wengang Zhang School of Civil Engineering Chongqing UniversityChongqing 400045China

Rainfall infiltration poses a disastrous threat to the slope stability in many regions around the *** paper proposes an extreme gradient boosting(XGBoost)-based stochastic analysis framework to estimate the rainfall-induced slope failure *** unsaturated slope under rainfall infiltration in spatially varying soils is selected in this study to investigate the influences of the spatial variability of soil properties(including effective cohesion c',effective friction angleφ'and saturated hydraulic conductivity k_(s)),as well as rainfall intensity and rainfall pattern on the slope failure *** show that the proposed framework in this study is capable of computing the failure probability with accuracy and high *** spatial variability of k_(s)cannot be overlooked in the reliability ***,the rainfall-induced slope failure probability will be *** is found that the rain-fall intensity and rainfall pattern have significant effect on the probability of ***,the failure probabilities under various rainfall intensities and patterns can be easily obtained with the aid of the proposed framework,which can provide timely guidance for the landslide emergency management departments.

关键词： Slope stability Rainfall infiltration Stochastic analysis Sspatial variability

A novel Zn-PANI dry rechargeable battery

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Rare Metals 2006年第z1期25卷 67-70页

作者： WANG xinsheng JIN xin gu Dawei SHEN Linjiang College of Science Nanjing University of Technology Nanjing 210009 China College of Science Nanjing University of Technology Nanjing 210009 China College of Science Nanjing University of Technology Nanjing 210009 China College of Science Nanjing University of Technology Nanjing 210009 China

Conducting polyaniline (PANI) powder was well mixed with graphite and acetylene black to obtain the optimum conductivity and porosity. The mixed powder was compressed into a pellet for cathode. Zinc powder was mixed with some metal powder, and compressed into a pellet used as the anode. The electrolyte comprised ZnCl2, NH4Cl, Triton-X100 and PVA at pH 3. The battery has an open-circuit voltage of 1.44 V. The battery underwent charge-discharge cycle with a constant current density of 3 mA·cm-2, within the voltage range of 0.40-1.68 V. It is found that the capacity of the battery is related to the charge-discharge cycles, the maximum capacity is 67.9 mAh·g-1, and Coulombic efficiency is between 95% and 100%. The battery stability was also investigated after 78 d of standing without use. It is found that the battery experiences a self-discharge of less than 0.29% per day.

关键词： polyaniline rechargeable battery capacity charge-discharge cycle