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Positive definiteness of fourth-order partially symmetric tensors

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Applied Mathematics(A Journal of Chinese Universities) 2023年第4期38卷 581-590页

作者： wang Hua-ge School of Mathematics and Information Science Henan Normal UniversityXinxiang 453007China Engineering Technology Research Center of Neurosense and Control of Henan Province Xinxiang Medical UniversityXinxiang 453003China

In this paper,we consider the positive definiteness of fourth-order partially symmetric tensors.First,two analytically sufficient and necessary conditions of positive definiteness are provided for fourth-order two dimensional partially symmetric tensors.Then,we obtain several sufficient conditions for rank-one positive definiteness of fourth-order three dimensional partially symmetric tensors.

关键词： partially symmetric tensor positive de niteness rank-one positive de nite

On the determination of particle impact breakage in selection function

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Particuology 2022年第6期20卷 117-132页

作者： Li Ge Wang Ruihuan ge Xizhong Chen Process Systems Enterprise HammersmithLondonUK Department of Chemical and Biological Engineering University of SheffieldUK Process and Chemical Engineering School of EngineeringUniversity College CorkIreland

This paper presents a thorough study of particle impact breakage in selection function with a unified breakage criterion.The impact mode and breakage pattern for particulate materials are classified based on a significant review of well-established impact testers.It was found that the lack of a unified breakage criterion to determine the breakage probability disables a direct comparison of particle breakage propensity from different impact loading testers.The literature breakage models to describe the breakage probability are reviewed where the advantage and drawback of these models are scrutinized.The sourced literature breakage models are compared with the zeolite breakage datasets in a unified breakage criterion to evaluate the model performance.A novel computational modelling workflow for a milling process is proposed to provide a guidance in implementing the digital twin in milling process prediction.The breakage probability models,i.***.the selection functions are comprehensively assessed in population balance model to examine the model serviceability.The model simplicity and fidelity in the model assessment are specifically discussed and the value of digital twin in substantially reducing the experimental trials is highlighted.

关键词： Impact breakage Breakage criteria Breakage model assessment Selection function Population balance model Digital twin

Evaluation of the Arctic Sea-Ice Simulation on SODA3 Datasets

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Advances in Atmospheric Sciences 2023年第12期40卷 2302-2317页

作者： Zhicheng ge Xuezhu wang Xidong wang Key Laboratory of Marine Hazards Forecasting Ministry of Natural ResourcesHohai UniversityNanjing 210098China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519000China Key Laboratory of Marine Science and Numerical Modeling Ministry of Natural ResourcesQingdao 266061China

This study evaluates the Arctic sea-ice simulation of the SODA3 dataset driven by different atmospheric forcing fields and explores the errors of the Arctic sea-ice simulation caused by the forcing field.We find that the SODA3 data driven by different forcing fields represent a significant systematical error in the simulation of Arctic sea-ice concentration,showing a low concentration of thick ice and a high concentration of thin ice.In terms of sea-ice extent,the SODA3 data from different versions well characterize the interannual variability and declining trend in the observed data,but they overestimate the overall Arctic sea-ice extent,which is related to excessive simulation of ice in the sea-ice margin.Compared to observations,all the chosen SODA3 reanalysis versions driven by different atmospheric forcing generally tend to underestimate the Arctic sea-ice thickness,especially for thick ice in the multi-year sea-ice regions.Inaccurate simulations of Arctic sea-ice transport may partly explain the error in SODA3 sea-ice thickness in multi-year sea-ice areas.The results of different SDOA3 versions differ greatly in the Beaufort Sea,the Fram Strait,and the Central Arctic Sea.The difference in sea-ice thickness among different SODA3 versions is primarily due to the thermodynamic contribution,which may come from the diversity of atmospheric forcing fields.Our work provides a reference for using SODA3 data to study Arctic sea ice.

关键词： Arctic sea-ice SODA3 simulation and evaluation sources of model error

Modeling of moral decisions with deep learning

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Visual Computing for Industry,Biomedicine,and Art 2020年第1期3卷 307-320页

作者： Christopher Wiedeman Ge Wang Uwe Kruger Department of Electrical and Computer Systems Engineering Rensselaer Polytechnic InstituteTroy NYUSA Department of Biomedical Engineering Rensselaer Polytechnic InstituteTroy NYUSA

One example of an artificial intelligence ethical dilemma is the autonomous vehicle situation presented by Massachusetts Institute of Technology researchers in the Moral Machine Experiment.To solve such dilemmas,the MIT researchers used a classic statistical method known as the hierarchical Bayesian(HB)model.This paper builds upon previous work for modeling moral decision making,applies a deep learning method to learn human ethics in this context,and compares it to the HB approach.These methods were tested to predict moral decisions of simulated populations of Moral Machine participants.Overall,test results indicate that deep neural networks can be effective in learning the group morality of a population through observation,and outperform the Bayesian model in the cases of model mismatches.

关键词： Artificial intelligence Deep learning Bayesian method Moral machine experiment

Comparison of tailpipe carbonyls and volatile organic compounds emissions from in-use gasoline/CNG bi-fuel vehicles

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Journal of Environmental Sciences 2024年第1期135卷 619-629页

作者： Jiachen Li Yunshan ge Xin wang Mengzhu Zhang Haohao wang School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China

Ground-level ozone contamination has been globally an urban air quality issue,particularly for China,which has recently made significant progress in purifying its sky.Unregulated exhaust emissions from motor vehicles,predominantly carbonyls and volatile organic compounds(VOCs),are among the leading contributors to ozone formation.In this chassislevel study,the unregulated emissions from five China-5 certified gasoline/CNG bi-fuel taxis,along with their ozone forming potential(OFP),were evaluated.It is found that carbonyls and VOCs were mainly emitted during the starting phase no matter the engine was cold or hot.Compared to gasoline,CNG fueling reduced VOCs emissions on a large scale,especially in the starting phase,but had elevated carbonyls.On a fleet average,CNG fueling derived 15%and 46%less OFP than gasoline in cold-and hot-start tests,respectively.VOCs contributed to over 90%of the total OFP of the exhaust.In terms of alleviating ground-level ozone contamination,CNG is a feasible alternative to gasoline on light-duty vehicles.

关键词： CNG Gasoline Carbonyls VOCs OFP

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珊瑚礁坪地形上波生流的流场特性分析

河海大学学报（自然科学版） 2018年第3期46卷 253-259页

作者：王国玉赵钦阳葛聪陈戈大连理工大学海岸和近海工程国家重点实验室辽宁大连116024

将珊瑚礁坪地形简化为向海坡为1∶1的陡坡,基于SPH方法,建立了波浪在珊瑚礁坪地形上传播的数值波浪水槽,模拟规则波浪在珊瑚礁坪地形上的传播变化过程,分析珊瑚礁坪附近的流场特性,并将数值模拟结果与实验室观测结果进行对比。结果表明... 详细信息

将珊瑚礁坪地形简化为向海坡为1∶1的陡坡,基于SPH方法,建立了波浪在珊瑚礁坪地形上传播的数值波浪水槽,模拟规则波浪在珊瑚礁坪地形上的传播变化过程,分析珊瑚礁坪附近的流场特性,并将数值模拟结果与实验室观测结果进行对比。结果表明,在波浪传播过程中由于水深变浅,波浪发生变形和破碎,在珊瑚礁坪顶周围的水体中将产生一个与波浪传播方向相同的流动。

关键词：珊瑚礁斜坡平台 SPH 流场分析数值水槽波浪传播

Primary hospitals in China: current state, challenges, and solutions

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Hepatobiliary Surgery and Nutrition 2023年第6期12卷 909-911页

作者： Ziyi wang ge Zhang Liaoning University of Traditional Chinese Medicine ShenyangChina Kaiyuan Central Hospital of Liaoning Province KaiyuanChina

When it comes to primary healthcare services,China’s primary medical system stands out with its unique attributes,shaped by China’s existing framework,cultural heritage,and the rapid growth of its economy and healthcare sector.Unlike established systems in the West,the healthcare landscape of China is in a constant state of evolution,adapting to its ever-changing society.

关键词： Primary state landscape

Mechanical and Rheological Properties of Bamboo Pulp Fiber Reinforced High Density Polyethylene Composites:Influence of Nano CaCO_(3)Treatment and Manufacturing Process with Different Pressure Ratings

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Journal of Renewable Materials 2022年第7期10卷 1829-1844页

作者： Cuicui wang Xin Wei Lee MSmith Ge Wang Shuangbao Zhang Haitao Cheng International Centre for Bamboo and Rattan Beijing100102China Department of Mechanical and Energy Engineering University of North TexasDenton76203USA Beijing Key Laboratory of Wood Science&Engineering College of Material Science&TechnologyBeijing Forestry UniversityBeijing100083China

In order to investigate the effect of the relative motion of nano CaCO_(3)reinforced bamboo pulp fiber(BPF)/HDPE composite components on the mechanical performance,a comparative study was performed.BPF was treated by nano CaCO_(3)blending(BM)and impregnation modification(IM)technology.The composites were produced using hot press(HPMP),extrusion(EMP)and injection molding process(IMP).The physical morphology of BPF was similar at different manufacturing processes.Compared to the samples manufactured by HPMP,a decrease in the(specific)flexural strength of BPF/HDPE composites and an increase in those of composites treated by nano CaCO_(3)manufactured by EMP and IMP were observed.The injection molded composites exhibited the best values in the(specific)impact strength,(specific)tensile properties.IM had a greater effect on the rheological behavior of the composites than BM,and nano CaCO_(3)treatment most effectively affected the performance of the extrusion molded composites.

关键词： Nano CaCO_(3) bamboo pulp fiber composites manufacturing process mechanical properties rheological properties

Constructive strategies for drug delivery systems in antivirus disease therapy by biosafety materials

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Biosafety and Health 2022年第3期4卷 161-170页

作者： Li wang Zhaoshuo wang Lingzhi Cao Kun ge Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education Key Laboratory of Chemical Biology of Hebei ProvinceCollege of Chemistry and Environmental ScienceHebei UniversityBaoding 071002China

Due to the coronavirus disease 2019(COVID‐19)pandemic,the development of antiviral drugs has attracted increasing attention.Clinical antiviral drugs show weak solubility,low bioavailability,adverse side effects,or only limited targets.With the advancement of nanotechnology and material science,biosafety nanomaterials have been constructed for drug delivery systems of antiviral disease therapy,such as liposomes,polymers,gold nanoparticles,and graphene.These nanodrug systems can either deliver synthesized antiviral drugs siRNA/miRNA and small molecular compounds,deliver bioactive large molecular drug proteins and mRNA,or show antiviral activity by themselves.Nanodelivery systems could effectively enhance the efficiency of antiviral drugs by increasing drug loading and host cell uptake with a small size and high specific surface area.This review focused on the biosafety nanomaterials used for antiviral therapy and discussed the options for the design of antiviral drugs in the future.

关键词： Antivirus therapy Nanodelivery systems Compound drugs Biologically active molecule drugs