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Science Letters:Three-dimensional conceptual model for service-oriented simulation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第8期10卷 1075-1081页

作者： wen-guang wang Wei-ping wang Justyna ZANDER Yi-fan ZHU College of Information System and Management National University of Defense Technology Changsha 410073 China Fraunhofer Institute FOKUS Kaiserin-Augusta-Allee 31 Berlin 10589 Germany

In this letter,we propose a novel three-dimensional conceptual model for an emerging service-oriented simulation paradigm. The model can be used as a guideline or an analytic means to find the potential and possible future directions of the current simulation frameworks. In particular, the model inspects the crossover between the disciplines of modeling and simulation, service-orientation,and software/systems engineering. Finally, two specific simulation frameworks are studied as examples.

关键词： Conceptual model Modeling and simulation Service-oriented architecture Systems engineering

Influence of Thinning on Soil CO_2 Efflux in Chinese Fir Plantations

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Pedosphere 2009年第3期19卷 273-280页

作者： wang guang-Jun Forest Ecology Section Faculty of Life Sciences and Technology Central South University of Forestry and TechnologyChangsha 410006 （China）

Forest management is expected to influence soil CO2 effiux （FCO2） as a result of changes in microenvironmental conditions, soil microclimate, and root dynamics. Soil EGO2 rate was measured during the growing season of 2006 in both thinning and non-thinning locations within stands ranging from 0 to 8 years after the most recent thinning in Chinese fir （Cunninghamia lanceolata （Lamb.） Hook） plantations in Huitong Ecosystem Research Station, Hunan, China. Soil temperature and moisture were also measured to examine relationships between FCO2 and soil properties. Forest thinning resulted in huge changes in FCO2 that varied with time since cutting. Immediately following harvest （year 0） FCO2 in thinning area increased by about 30%, declined to 20%-27% below pre-cutting levels during years 4-6, and recovered to pre-cutting levels at 8 years post-cutting. A similar temporal pattern, but with smaller changes, was found in non-thinning locations. The initial increase in FCO2 could be attributed to a combination of root decay, soil disturbance, and increased soil temperature in gaps, while the subsequent decrease and recovery to the death and gradual regrowth of active roots. Strong effects of soil temperature and soil water content on FCO2 were found. Forest thinning mainly influenced FCO2 through changes in tree root respiration, and the net result was a decrease in integrated FCO2 flux through the entire felling cycle.

关键词： forest soil moisture soil properties soil respiration soil temperature

Experimental and numerical study on energy dissipation in freely cooling granular gases under microgravity

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Chinese Physics B 2018年第8期27卷 324-330页

作者： wen-guang wang Mei-Ying Hotl Ke Chen Pei-Dong Yu Matthias Sperl Key Laboratory of Soft Matter Physics Beijing National Laboratory for Condensed Matter PhysicsInstitute of Physics Chinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Institut fr Materialphysik im Weltraum Deutsches Zentrum fiir Luft-und RaumfahrtKOln 51170Germany

Energy dissipation is one of the most important properties of granular gas, which makes Its behavior dltterent trom that of molecular gas. In this work we report our investigations on the freely-cooling evolution of granular gas under microgravity in a drop tower experiment, and also conduct the molecular dynamics （MD） simulation for comparison. While our experimental and simulation results support Haff＇s law that the kinetic energy dissipates with time t as E（t）（1 ＋ t/v） 2, we modify ~＂ by taking into account the friction dissipation during collisions, and study the effects of number density and particle size on the collision frequency. From the standard deviation of the measured velocity distributions we also verify the energy dissipation law, which is in agreement with Haff＇s kinetic energy dissipation.

关键词： granular gas freely coolin microgravity

Constructing Tertiary Alcohols with Vicinal Stereocenters:Highly Diastereo-and Enantioselective Cyanosilylation of α-Branched Acyclic Ketones and Their Kinetic Resolution

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CCS Chemistry 2022年第6期4卷 2140-2152页

作者： wen-Biao Wu Xin Yu Jin-Sheng Yu Xin wang wen-guang wang Jian Zhou Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesEast China Normal UniversityShanghai 200062 School of Chemistry and Chemical Engineering Shandong UniversityJinan 250100 College of Chemistry Sichuan UniversityChengdu 610064 State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryShanghai 200032

We report the first highly diastereo-and enantioselective C-C bond-forming reaction of racemic α-branched ketones to construct tertiary alcohols with adjacent ***,a highly stereoselective cyanosilylation of racemic ketones is developed using our bifunctional cyanating reagent,Me_(2)(CH_(2)Cl)SiCN,giving C^(α)-tetrasubstituted silyl cyanohydrins withtwovicinal stereocenters inupto>20:1 diastereomeric ratio(dr)and 90-98% enantiomeric excess(ee)values,which can undergo various diversification reactions bymanipulating the chloromethyl group.A highly selective kinetic resolution of acyclicα-branched ketones is also developed that allows facile access to acyclic α-alkyl,allyl,and propargyl ketones with good recovery and excellent ee *** synthetic value of this protocol is further demonstrated by the formal synthesis of the anti-obesity agent,taranabant(MK-0364).The activation of Jacobsen’s privileged catalyst(salen)AlCl by a suitable phosphorane plays a crucial role in the reaction.X-ray crystallographic analysis of single crystals of phosphorane-(salen)AlCl complexes and theoretical calculations help provide a working *** present transformation opens a new path for the catalytic stereoselective synthesis of stereochemically complex tertiary alcohols featuring two stereocenters(adjacent or not)from racemic ketones.

关键词： tertiary alcohols with vicinal stereocenters ketone cyanosilylation kinetic resolution

A Novel Method for Forecasting Freak Wave Occurrence in A Short Crested Coastal Sea

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China Ocean Engineering 2024年第1期38卷 104-116页

作者： wang Ying-guang State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Ocean and Civil Engineering Shanghai Jiao Tong UniversityShanghai 200240China

In order to forecast the distribution of crest amplitudes and the occurrence of freak waves in a short crested coastal sea,a novel transformed linear simulation method is initially proposed in this paper.A Hermite transformation model expressed as a monotonic cubic polynomial serves as the foundation for the novel simulation *** wave crest amplitude exceedance probabilities of two sea states-one with a directional wave spectrum based on the measured wave elevation data at the Yura coast and the other with a typical directional JONSWAP wave spectrum-have been predicted using the novel simulation method that has been *** likelihood that a particular critical wave crest amplitude will be exceeded is directly correlated with the probability that freak waves will *** is shown that the novel simulation approach suggested can provide predictions that are more precise than those obtained from the Rayleigh crest amplitude distribution model,the Jahns and Wheeler crest amplitude distribution model,or the conventional linear simulation *** study also demonstrated that the nonlinear simulation method is less effective than the novel simulation method in terms of efficiency.

关键词： wave crest amplitude freak waves short crested sea transformed linear simulation

Predictors of atrial fibrillation after coronary artery bypass graft： a meta-analysis

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Journal of Geriatric Cardiology 2009年第3期6卷 162-167页

作者： Liang Yin Zhi-Nong wang Yi-Feng wang wen-Tao wang guang-Yu Ji Xin-Wei Yang Zhi-Yun Xu Department of Cardiothoracic Surgery Changhai Hospital Second Military Medical University of PLA Shanghai 200433 China

Objectives Postoperative atrial fibrillation （AF） has been associated with less favorable outcomes in patients undergoing coronary artery bypass graft surgery （CABG） and may result in increased post-operative morbidity and mortality. A systematic review and meta-analysis of published studies was conducted to examine the risk factors of occurrence AF after CABG. Methods Using the Medline database, the Cochrane clinical trials database and online clinical trial databases, we reviewed all randomized controlled trials （RCTs） and observational studies examining the risk factors of occurrence of AF after CABG. We searched for literature published April 2009 or earlier. Results Our review identified 8 studies （observational studies）, involving 14548 patients, that examined the risk factors of occurrence of AF after CABG. Although studies provide conflicting results, the overall outcomes suggests that advanced age, previous hypertension, numbers of bridge vessels may increase the occurrence of AF after CABG, while no significant difference of diabetes, preoperative myocardial infarction, and preoperative medication of 13 -Blocker have been observed between the AF patients and no-AF patiens. Conclusions Patients with advanced age, previous hypertension and more numbers of bridge vessels had higher risk for the occurrence of AF after CABG, and perioperative medication and care must be intensified to decrease the postoperative occurrence ofAF（J Geriatr Cardio12009; 6：162-167）.

关键词： atrial fibrillation coronary artery bypass graft postoperative meta-analysis predictors

THE SOLID STATE CONTROLLED PHOTOCHEMICAL REACTION OF NITROBENZALDEHYDE WITH INDOLE

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Chinese Chemical Letters 1992年第11期3卷 865-868页

作者： Ji Ben MENG Da Ming DU Guo Xiang XIONG wen guang wang Yong Mei wang Department of chemistry.Nankai university Tianjin300071

The solid state photochemical reaction of nitrobenzaldehyde with indole was investigated. Seven hey products were identified by IR, MS,^(1)H HMR and elemental analysis.

关键词： wang THE SOLID STATE CONTROLLED PHOTOCHEMICAL REACTION OF NITROBENZALDEHYDE WITH INDOLE high

Dietary cooking oils and cardiometabolic measurements in an elderly Chinese population

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Journal of Geriatric Cardiology 2024年第6期21卷 642-650页

作者： Xin-Yu wang Chao-Ying MIAO Xiao-Fei YE wen-Yuan-Yue wang Jia-Bo ZHU Yi ZHOU Yan LI Ji-guang wang School of Public Health Shanghai Jiao Tong University School of MedicineShanghaiChina Department of Cardiovascular Medicine Centre for Epidemiological Studies and Clinical TrialsThe Shanghai Institute of HypertensionRuijin HospitalShanghai Jiao Tong University School of MedicineShanghaiChina

OBJECTIVE To investigate three features of dietary cooking oil intake,namely,the consumption,cooking style,and composition of fatty acids in relation to several cardiometabolic measurements in an elderly Chinese *** The elderly(≥65 years)participants for this study were recruited from two community health centers in the urban area of Shanghai.A questionnaire was administered to collect information on dietary oil consumption(low,medium and high)and cooking styles(fry or stir-fry ***)and the composition of fatty acids(poly-unsaturated ***-unsaturated).The cardiometabolic measurements included anthropometry,blood pressure,fasting plasma glucose and serum *** The 1186 study participants had a mean age of 70.9±5.4 *** mean dietary oil consumption was 35.0 g/d,being low(<25 g/d),medium(25-49 g/d)and high(≥50 g/d)in 485,467 and 234 participants,*** proportion of the fry or stir-fry cooking style and oils rich in mono-unsaturated fatty acids was 30.4%and 27.4%,*** before and after adjustment for sex,age,current smoking and alcohol intake,dietary oil consumption was significantly(P≤0.02)and positively associated with the prevalence of treated hypertension and fasting plasma glucose *** similar adjustments as above and additional adjustment for dietary oil consumption,the fry or stir-fry cooking style was significantly(P≤0.048)and positively associated with body mass index,but inversely with systolic and diastolic blood pressure and serum low-density lipoprotein cholesterol,and the dietary intake of oils rich in mono-unsaturated fat acids was significantly(P≤0.02)and positively associated with diastolic blood pressure,serum triglycerides,total cholesterol and low-density lipoprotein cholesterol,and the prevalence of hypertriglyceridemia and *** This study showed that both the consumption and composition of fatty acids of the dietary oils mattered with regard to sev

关键词： cooking elderly unsaturated

Differentially private SGD with random features

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 1-23页

作者： wang Yi-guang GUO Zheng-chu Polytechnic Institute of Zhejiang University Zhejiang UniversityHangzhou 310015China School of Mathematical Sciences Zhejiang UniversityHangzhou 310058China

In the realm of large-scale machine learning,it is crucial to explore methods for reducing computational complexity and memory demands while maintaining generalization ***,since the collected data may contain some sensitive information,it is also of great significance to study privacy-preserving machine learning *** paper focuses on the performance of the differentially private stochastic gradient descent(SGD)algorithm based on random *** begin,the algorithm maps the original data into a lowdimensional space,thereby avoiding the traditional kernel method for large-scale data storage ***,the algorithm iteratively optimizes parameters using the stochastic gradient descent ***,the output perturbation mechanism is employed to introduce random noise,ensuring algorithmic *** prove that the proposed algorithm satisfies the differential privacy while achieving fast convergence rates under some mild conditions.

关键词： learning theory differential privacy stochastic gradient descent random features reproducing kernel Hilbert spaces