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Uniqueness and local stability for the inverse scattering problem of determining the cavity

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Science china mathematics 2005年第8期48卷 1113-1123页

作者： FENG Lixin & ma Fuming lmam, school of mathematical sciences,{3., Beijing 100871, china school of mathematical sciences, Heilongjiang university, Harbin 150080, china school of mathematical sciences, Jilin university, Changchun 13.012, china 1. lmam School of Mathematical Sciences Peking University 100871 Beijing China 2. school of mathematical sciences Heilongjiang University 150080 Harbin China 3. school of mathematical sciences Jilin University 130012 Changchun China

Considering a time-harmonic electromagnetic plane wave incident on an arbitrarily shaped open cavity embedded in infinite ground plane, the physical process is modelled by maxwell's equations. We investigate the inverse problem of determining the shape of the open cavity from the information of the measured scattered field. Results on the uniqueness and the local stability of the inverse problem in the 2-dimensional TM (transverse magnetic) polarization are proved in this paper.

关键词： uniqueness, stability, maxwell's equations, inverse scattering problem.

Engineering Fronts 2023.announced engineering fronts in fields of Energy and Electrical Science and Technology

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Frontiers in Energy 2024年第1期18卷 4-7页

作者： ruiqin LIU Liang YIN Lingxiao FU Editorial Office of Frontiers in Energy Shanghai Jiao Tong UniversityShanghai 200240China

1 Introduction An engineering front refers to important directions that have a significant impact on and lead the future innovation of engineering science and *** is characterized by its forward looking,leading,and exploratory *** 2017,the Chinese Academy of Engineering(CAE)has annually organized a project known as“Global Engineering Fronts,”identifying and releasing engineering research fronts and engineering development fronts,tracking the trends in engineering science and technology,and actively guiding the academic development and promoting innovation in engineering science and technology.

关键词： technology. annually looking

Abundance and sources of particulate polycyclic aromatic hydrocarbons and aromatic acids at an urban site in central china

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Journal of Environmental sciences 2024年第8期142卷 155-168页

作者： Luqi Shang Zhe Dong Zihan Li Mingkai Wang Zihan Kong Xiao Li ruiqin Zhang school of Ecology and Environment Zhengzhou UniversityZhengzhou 450001China College of Chemistry Zhengzhou UniversityZhengzhou 450001China Institute of Environmental sciences Zhengzhou UniversityZhengzhou 450001China

We conducted a simultaneous field study of PM_(2.5)-bound particulate polycyclic aromatic hydrocarbons(PAHs)and aromatic acids(AAs)in a polluted city Zhengzhou to explore the concentration,sources and potential conversion pathways between PAHs and AAs in different *** average concentrations of PM_(2.5),28PAHs and 8AAs during the sampling period were 77μg/m^(3.,75 ng/m^(3.,and 283.ng/m^(3.,*** concentration of both28PAHs and 8AAs were highest in winter and lowest in summer with ratios of 6.3.and 2.3.*** with 5-7 rings were the main components of PAHs(52%),followed by 4rings PAHs(3.%)and 2-3.rings PAHs(18%).According to the source appointment results obtained by positive matrix factorization,the main sources of PAHs were combustion and vehicle emissions,which account for 3.%and 3.%,respectively.8AAs were divided into three groups,including four benzene dicarboxylic acids(B2CAs),three benzene tricarboxylic acids(B3.As)and one benzene tetracarboxylic acid(B4CA).And interspecies correlation analysis with PM_(2.5)source markers were used to investigate potential *** acid(o-Ph)was the most abundant specie of 8AAs(157 ng/m^(3.,55%of 8AAs),which was well correlated with ***,B3.As and B4CA were highly correlated with sulfate and weakly correlated with levoglucosan,suggesting that secondary formation was their main *** logical oxidation products of PAHs,o-Ph and B3.As showed good correlations with a number of PAHs,indicating possible photochemical oxidation pathway by *** addition,O_(3.,NO_(2),temperature and relative humidity have positive effects on the secondary formation of B3.As.

关键词： Polycyclic aromatic hydrocarbons Aromatic acids Source appointment Secondary formation

A Study on the Role of Tourism in Enhancing Personal Mental Health in the Post-Epidemic Era

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International Journal of Mental Health Promotion 2024年第4期26卷 325-334页

作者： ruiqin Tian Yue Feng Lingqi Zhan school of mathematics Hangzhou Normal UniversityHangzhou311121China

With the advent of the post-epidemic era,a great wave of tourism has been ushered in *** relationship between tourism and mental health has become a hot topic in *** paper investigates the enhancement of people’s mental health after tourism through social *** Hangzhou as the sample collection site,this paper conducted a study on the role of tourism in enhancing personal mental health through descriptive analysis,factor analysis and structural equation modeling,and further specifically analyzed the role of mediating *** results showed that:(1)The purpose of tourism is to relax and relieve stress,and the effectiveness of tourism is mainly reflected in the alleviation of emotional conditions;(2)Factor Analysis reduced the dimensionality of personal mental health indicators,and finally obtained four factors,among which the comprehensive behavioral ability and physiological manifestation had the best improvement effect after tourism;(3.The structural equation model shows that the enhancing effect of tourism on mental health originates from the factor of inner psychological characteristic,and this factor works through two paths:Inner Psychological Characteristic-Social Adaptability-Physiological manifestations-Enhancement of Mental Health by Tourism,and Inner Psychological Characteristic-Comprehensive Behavioral Ability-Enhancement of Mental Health by Tourism;(4)Tourism has an enhancing effect on personal mental health,and the enhancing effect is most significant among the middle-aged and young people who are unmarried and do not have children *** results have been reasonably analyzed and explained,and relevant suggestions are put forward.

关键词： Tourism mental health factor analysis structural equation model enhancement

Analytical model of vertical load acting on jacked pipe considering soil arching effect in cohesionless soil

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Underground Space 2024年第1期14卷 263-284页

作者： Yu Zhang Lianjin Tao Xu Zhao Jun Liu Weizhang Liao Fei Guo Xiaohui Yang ruiqin Zhong Beijing Advanced Innovation Center for Future Urban Design Beijing University of Civil Engineering and ArchitectureBeijing 102627China The Key Laboratory of Urban Security and Disaster Engineering Ministry of EducationBeijing University of TechnologyBeijing 100024China Beijing Municipal Construction Group Co. LtdBeijing 100045China Beijing Municipal Engineering Institute Beijing 100037China

For the project of pipe jacking in cohesionless soil,it is key to determine the vertical load on jacked pipe so as to predict the jacking force *** this paper,a new parabolic soil arching model was proposed to calculate the vertical load on jacked *** proposed analytical model was composed of parabolic soil arching zone,parabola-typed collapse zone and friction arch *** with existing literature,the key parameters(i.e.,height of parabolic soil arching,horizontal pressure coefficient and width and height of friction arch)were *** addition,considering that the trajectory of major stress is parabola,the formula of horizontal pressure coefficient was deduced in the friction *** parabolic soil arching zone is assumed as a three-hinged arch with reasonable arch axis,and the formula of load transfer was derived considering the transition effect of parabolic soil *** results of experiment,theoretical models and numerical model were adopted to verify the proposed analytical ***,the influence of the key parameters on the vertical load on jacked pipe were also discussed in *** work provides a meaningful reference for evaluating the vertical load on jacked pipe for design of pipe jacking.

关键词： Jacked pipe Soil arching effect Theoretical model Parabolic soil arching model Vertical load

Weyl transform associated with wavelets

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Progress in Natural Science:materials International 2003年第7期 19-22页

作者： ma ruiqin and PENG Lizhong(lmam,{3., peking university, Beijing 100871, china) lmam School of Mathematical Sciences Peking University Beijing 100871 China

The Weyl transform on the admissible wavelet space is defined, which is associated with the dilation and translation. And the criteria of its boundedness and compactness on the Lp-spaces are given.

关键词： affine group dilation and translation admissible wavelet Weyl transform bonndeness compactness.

Split-plot designs with general minimum lower-order confounding

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Science china mathematics 2010年第4期53卷 939-952页

作者： WEI JiaLin 1,4,YANG JianFeng 1,LI Peng 3.& ZHANG RunChu 1,2,1 school of mathematical sciences and LPMC,Nankai university,Tianjin 3.0071,china 2 KLAS and{3. of mathematics and Statistics,Northeast Normal university,Changchun 13.024,china 3.0},Capital Normal university,Beijing 10003.,china 4{3. of sciences,Tianjin university of Commerce,Tianjin 3.013.,china 1. school of mathematical sciences and LPMC Nankai University Tianjin 300071 China4. School of Sciences Tianjin University of Commerce Tianjin 300134 China3. School of Mathematical Sciences Capital Normal University Beijing 100037 China2. KLAS and School of Mathematics and Statistics Northeast Normal University Changchun 130024 China

Split-plot designs have been widely used in industrial *** to now,most methods for choosing this kind of designs are based on the minimum aberration (ma) ***,by introducing a new pattern,called aliased effect-number pattern (AENP),Zhang et *** a general minimum lowerorder confounding (denoted by GMC for short) criterion and established a general minimum confounding (also denoted by GMC for saving notations) *** is proved that,the GMC criterion selects optimal designs in a more elaborate manner than the existing ones,and when an experimenter has a prior about the importance ordering of factors in experiments the GMC designs are better than other optimal *** this paper we extend the GMC criterion to the split-plot design case and give a GMC-FFSP criterion for ranking split-plot *** comparisons of the new criterion with the ma-MSA-FFSP criterion are given,and the optimal 3.-run split-plot designs up to 14 factors under the two criteria are tabulated for comparison and application.

关键词： fractional factorial design GMC criterion minimum aberration split-plot

TRANSPORTATION INEQUALITIES FOR WEAKLY DEPENDENT SEQUENCES

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Acta mathematica Scientia 2011年第4期31卷 1494-1502页

作者：马宇韬 school of mathematical sciences Beijing Normal University

In [3., they gave necessary and sufficient condition for T 1 C and then as applications T 1 C for weakly dependent sequences was established. In this note, based on Gozlan-L′eonard characterization for W 1 H -inequal... 详细信息

关键词： W 1 H inequality T p (C)-inequality weakly dependent sequences tensorization

Birth-death processes on trees

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Science china mathematics 2010年第11期53卷 2993-3004页

作者： ma YuTao school of mathematical sciences & Laboratory of mathematics and Complex Systems, Beijing Normal university, Beijing 100875, china 1. school of mathematical sciences & Laboratory of mathematics and Complex Systems Beijing Normal University Beijing 100875 China

In this paper, we consider birth-death processes on a tree T and we are interested when it is regular, recurrent and ergodic (strongly, exponentially). By constructing two corresponding birth death processes on Z+, we obtain computable conditions sufficient or necessary for that (in many cases, these two conditions coincide). With the help of these constructions, we give explicit upper and lower bounds for the Dirichlet eigenvalue λ0. At last, some examples are investigated to justify our results.

关键词： birth-death process tree ergodicity Dirichlet eigenvalue