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Preface——Special Issue to Celebrate the 30th Anniversary of Journal of Systems Science and Complexity

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Journal of Systems Science & Complexity 2017年第1期30卷 1-3页

作者： GAO Xiao-Shan CHEN Jie shao jun WANG Shouyang Academy of Mathematics and Systems Science Chinese Academy of Sciences Key Laboratory of Intelligent Control and Design of Complex Systems Beijing Institute of Technology Department of Statistics University of Wisconsin-Madison

This special issue is dedicated to the 30th anniversary of Journal of Systems Science and Complexity(JSSC)which is under the auspices of the Institute of Systems Science,Chinese Academy of *** of Systems Science,Chinese Academy of Sciences was established in 1979 by scientists Chao-Chih Kwan,Wen-Tsun Wu,Guo-Zhi *** 1981,the Journal of Systems

关键词：系统科学复杂性杂志中国科学院序言科学研究所

A micromechanical bridge-shaped voltage-controlled oscillator

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Science China(Technological Sciences) 2004年第1期47卷 26-32页

作者： HAN Jianqiang ZHU Changchun ZHAO Hongpo LIU junhua shao jun Xi'an Jiaotong University Xi'an 710049 China Xi'an Jiaotong University Xi'an 710049 China Xi'an Jiaotong University Xi'an 710049 China Xi'an Jiaotong University Xi'an 710049 China Xi'an Jiaotong University Xi'an 710049 China

A novel micromechanical bridge-shaped voltage-controlled oscillator with high Q value was fabricated. The core of this kind of oscillators is an electrothermally excited and piezoresistively detected micromechanical bridge resonator. Its resonance frequency can be adjusted by changing the DC voltage applied to the Wheatstone bridge. Theoretical analysis and experimental data show that its resonance frequency is linear with the square of the DC voltage. The linearity is better than 0.16% and the adjustable frequency range excels 17.15%.

关键词： voltage-controlled oscillator, microbridge, resonator, MEMS.

A Novel Method for Modification of SMPU by Micro-phase Separation Promoters

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Chinese Chemical Letters 2005年第9期16卷 1241-1244页

作者： shao jun CHEN Jing Cang SU Peng Sheng LIU Research Institute of Polymeric Materials Xiangtan University Xiangtan 411105

A novel method of controlling the shape memory properties of shape memory polyurethane （SMPU） by addition of micro-phase separation promoters including 1-octadecanol （ODO） and liquid paraffin （LP） is reported. The results indicate that the strain recovery temperature and the strain modulus rate （Eg/Er） were increased significantly with addition of small amount of micro-phase separation promoters. Thus it can increase the shape memory fixity rate and other shape memory behaviors of SMPU.

关键词： Shape memory polyurethane modification micro-phase separation

Design strategy of phase and microstructure of Si_(3)N_(4) ceramics with simultaneously high hardness and toughness

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Journal of Advanced Ceramics 2023年第1期12卷 122-131页

作者： shao-jun TANG Wei-Ming GUO Shi-Kuan SUN Hua-Tay LIN School of Electromechanical Engineering Guangdong University of TechnologyGuangzhou 510006China School of Material Science and Energy Engineering Foshan UniversityFoshan 528000China

Aiming to achieve silicon nitride( Si_(3)N_(4))ceramics with high hardness and high toughness,the relationships among phase composition,microstructure,and mechanical properties of Si_(3)N_(4) ceramics prepared by spark plasma sintering(SPS)at temperatures ranging from 1500 to 1800℃were investigated in this *** stages with different phase and microstructure features were observed and ***α-βphase transformation occurs first,and the development and growth of grains lag *** the first stage,the average grain size remains basically unchanged,and the hardness maintains at a value of~20.18±0.26 GPa,despite theβ- Si_(3)N_(4) phase fraction increases from 7.67 to 57.34 wt%.Subsequently,the equiaxed grains transform into rod-like grains with a high aspect ratio via the reprecipitation process,resulting in a significant increase in the fracture toughness from 3.36±0.62 to 7.11±0.15 MPa·m^(1/2).In the second stage of sintering process,the fraction ofβ- Si_(3)N_(4) phase increases to 100.00 wt%,and the grain growth also rapidly ***,the fracture toughness increases slightly to 7.61±0.42 MPa·m^(1/2),but the hardness reduces to 16.80±0.20 *** current results demonstrate that the phase contents ofβ- Si_(3)N_(4) and the microstructure shall be carefully tailored to achieve high-performance Si_(3)N_(4) ceramics. Si_(3)N_(4) ceramics with a finegrained bimodal microstructure,consisting of the mainα-andβ-phases,can exhibit the optimized combination of hardness and toughness.

关键词： silicon nitride(Si_(3)N_(4)) phase composition microstructure hardness toughness

A discussion of ‘prior-based Bayesian information criterion (PBIC)’

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Statistical Theory and Related Fields 2019年第1期3卷 19-21页

作者： jun shao Sheng Zhang Department of Statistics University of Wisconsin-MadisonMadisonWIUSA

Professors Bayarri,Berger,Jang,Ray,Pericchi,and Visser deserve a special congratulation for their great work on Bayesian model and variable selection and a pioneering idea of prior-based Bayesian information criterion... 详细信息

关键词： criterion prior contemporary

Nearest neighbour imputation under single index models

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Statistical Theory and Related Fields 2019年第2期3卷 208-212页

作者： jun shao Lei Wang School of Statistics East China Normal UniversityShanghaiPeople’s Republic of China Department of Statistics University of WisconsinMadisonWIUSA School of Statistics and Data Science&LPMC Nankai UniversityTianjinPeople’s Republic of China

A popular imputation method used to compensate for item nonresponse in sample surveys is thenearest neighbour imputation (NNI) method utilising a covariate to defined neighbours. Whenthe covariate is multivariate, however, NNI suffers the well-known curse of dimensionality andgives unstable results. As a remedy, we propose a single-index NNI when the conditional meanof response given covariates follows a single index model. For estimating the population meanor quantiles, we establish the consistency and asymptotic normality of the single-index NNI estimators. Some limited simulation results are presented to examine the finite-sample performanceof the proposed estimator of population mean.

关键词： Asymptotic normality curse of dimensionality imputation mean quantiles SAVE

Passive Smoking in China: Contributing Factors and Areas for Future Interventions

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Biomedical and Environmental Sciences 2007年第5期20卷 420-425页

作者： shao-jun MA jun-FANG WANG CUI-ZHU MEI XUE-FANG XU GONG-HUAN YANG Institute of Basic Medical Sciences Chinese Academy of Medical Sciences and School of Basic Medicine Peking Union Medical College Beijing 100005 China School of Public Health Peking Union Medical College Beijing 100005 China Chinese Center for Disease Control and Prevention Beijing 100050 China

Objective To reduce tobacco consumption and exposure to passive smoking in China. Methods Discussion consisting of 80 focus groups and 35 interviews were held in three rural intervention counties of Jiangxi, Henan, and Sichuan Provinces. Participants came from hospitals, schools, rural areas, and urban areas. Results Tobacco use and exposure to passive smoking were widely prevalent in the investigated schools, hospitals, county towns, and rural areas. Knowledge of the risks for passive smoking on health is lacking, especially in rural areas. Barriers to the control of tobacco use in public places include reluctance of administrators to implement tobacco control policies, lack of consistent policies, difficulties with regulations and enforcement, and reluctance of non-smokers to exercise their right to clean air. Conclusion To curb the current tobacco epidemic in China, tobacco control efforts must focus on reducing exposure to passive smoking. A strategy should be formulated to reduce the factors that contribute to tobacco use and exposure to passive smoking.

关键词： Qualitative study Passive smoking China

Effects of Molecular Weight on the Crystallization and Melting Behaviors of Poly(L-lactide)

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Chinese Journal of Polymer Science 2016年第1期34卷 69-76页

作者： Sheng Xiang shao jun 李杲边新超 Li-dong Feng Xue-si Chen Feng-qi Liu shao-yong Huang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences College of Chemistry and Chemical Engineering Jiangxi Normal University College of Chemistry Jilin University

In this study, a series of monodispersed poly（L-lactide）（PLLA） were synthesized by the ring-opening polymerization with Schiff base aluminum catalyst, and the effects of the number-average molecular weight（Mn） on the crystallization and melting behaviors of PLLA were investigated by differential scanning calorimetry（DSC） and wide-angle X-ray diffraction（WAXD）. The total crystallization rate of PLLA was Mn-dependent, which reached the maximum value for PLLA with Mn of 18.6 kg/mol. In addition, when Mn of PLLA was 18.6 kg/mol, the melting enthalpy（ΔHm） showed a maximum value（87.1 J/g）, which was the highest reported value till now. The critical temperature for change of crystal formation from ？-form to ？-form crystals increased in the isothermal crystallization process with Mn increasing. In the reheating procedure, high-Mn PLLA demonstrated a small exothermal peak prior to the dominant melting peak, corresponding to crystal transition from ？- to ？-form, but low-Mn PLLA didn＇t show the peak of crystal transition. These different crystallization and melting behaviors were attributed to the different chain mobility of PLLA with different Mn.

关键词： Poly(L-lactide) Crystallization behavior Melting behavior Crystal transition

Formation process of meandering channel by a 2D numerical simulation

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International Journal of Sediment Research 2012年第3期27卷 306-322页

作者： Yi XIAO Xue-jun shao Hong WANG Gang ZHOU State Key Laboratory of Hydroscience and Engineering Tsinghua University Post-doctoral research fellow Chinese Research Academy of Environmental Sciences

A 2D depth-averaged model for hydrodynamic,sediment transport and river morphological adjustment is *** sediment transport submodel considers non-uniform sediment,bed surface armoring,impact of secondary flow on the direction of bed-load transport,and transverse slope of river *** bank erosion submodel incorporates a simple simulation method for updating bank geometry during either degradational or aggradational bed *** model is applied to a 180°bend with a constant radius under unsteady flow conditions,and to Friedkin’s laboratory meander *** results are in acceptable agreement with measurements,confirming the two dimensional model’s potential in predicting the formation of river meandering and improving understanding of patterning *** researches are needed to clarify some simplifications and limitations of the model.

关键词： River morphology Armored beds Non-uniform sediment Bank erosion 2D numerical model