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Acta Metallurgica Sinica(English Letters) 2021年第10期34卷 1375-1385页

作者： Chunliang Yang Chuansong Wu junjie Zhao MOE Key Lab for Liquid-Solid Structure Evolution and Materials Processing Institute of Materials JoiningShandong UniversityJinan 250061China

An atomic diffusion model is developed to predict the thickness of intermetallic compounds(IMCs)at the interface of aluminum/magnesium alloys in dissimilar friction stir *** the temperature and the strain rate associated with dislocation density at the checking point are used to determine the diffusion *** variations of the diffusion coefficients and the thickness of IMCs are quantitatively analyzed at selected characteristic time instants during welding *** is found that the dislocation density can increase the diffusion coefficient and plays a dominant role in the IMCs formation during the plastic deformation *** in magnesium alloy and Al12Mg17,the diffusion coefficient is increased by two orders of magnitude or even nearly three orders of magnitude by considering the dislocation *** temperature is the main influencing factor after the end of plastic *** model is validated by comparing the predicted thickness of IMCs with the experimentally measured results.

关键词： Friction stir welding Aluminum alloys Magnesium alloy Intermetallic compounds Atomic diffusion Strain rate

Robust topology optimization of hinge-free compliant mechanisms with material uncertainties based on a non-probabilistic field model

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Frontiers of Mechanical Engineering 2019年第2期14卷 201-212页

作者： junjie ZHAN Yangjun LUO State Key Laboratory of Structural Analysis for Industrial Equipment School of Aeronautics and AstronauticsDalian University of TechnologyDalian 116024China

This paper presents a new robust topology optimization framework for hinge-free compliant mechanisms with spatially varying material uncertainties,which are described using a non-probabilistic bounded field *** field uncertainties are efficiently represented by a reduced set of uncertain-but-bouncled coeflficients on the basis of the series expansion *** topology optimization of compliant mechanisms is then defined to minimize the variation in output displacement under constraints of the mean displacement and predefined material *** nest optimization problem is solved using a gradient-based optimization *** examples are presented to illustrate the effectiveness of the proposed method for circumventing hinges in topology optimization of compliant mechanisms.

关键词： compliant mechanisms robust topology optimization hinges uncertainty bounded field

A novel amperometric biosensor based on gold nanoparticles-mesoporous silica composite for biosensing glucose

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Science China Chemistry 2009年第6期52卷 815-820页

作者： ZHANG JingJing ZHU junjie Key Laboratory of Analytical Chemistry for Life Science Ministry of EducationSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093China

We report a novel bienzyme biosensor based on the assembly of the glucose oxidase (GOD) and horseradish peroxidase (HRP) onto the gold nanoparticles encapsulated mesoporous silica SBA-15 composite (AuNPs-SBA-15). Electrochemical behavior of the bienzyme bioconjugates biosensor is studied by cyclic voltammetry and electrochemical impedance spectroscopy. The results indicate that the presence of mesoporous AuNPs-SBA-15 greatly enhanced the protein loadings, accelerated interfacial electron transfer of HRP and the electroconducting surface, resulting in the realization of direct electrochemistry of HRP. Owing to the electrocatalytic effect of AuNPs-SBA-15 composite, the biosensor exhibits a sensitive response to H2O2 generated from enzymatic reactions. Thus the bienzyme biosensor could be used for the detection of glucose without the addition of any mediator. The detection limit of glucose was 0.5 μM with a linear range from 1 to 48 μM.

关键词： bienzyme electrode mesoporous silica glucose amperometric detection

Research on volumetric error compensation for NC machine tool based on laser tracker measurement

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Science China(Technological Sciences) 2012年第11期55卷 3000-3009页

作者： WANG JinDong GUO junjie State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong UniversityXi'an 710049China

Error compensation is an effective method to improve the accuracy of NC machine *** compensation results are greatly affected by the error modeling and error measurement,so how to establish an accurate error model and accurately detect the geometric errors of machine tool are particularly *** the paper,the volumetric error model of a multi-axis NC machine tool is established based on the multi-body system *** relative position deviations between the rotary axis and linear axis of the machine tool are considered in the *** achieve quick and accurate detection,a laser tracker is based on the multi-station and time-sharing measurement principle to detect the geometric errors of machine tool,and each error of linear axis and rotary axis can be identified by this *** the error model,error compensation can be carried out by modifying the machining process(G code),and the machining accuracy can be improved with the new G *** results show that the motion errors of a milling machine are significantly reduced after compensation,which verifies the effectiveness of compensation method.

关键词： error modeling multi-body system theory laser tracker error compensation

Biological and clinical aspects of HPV-related cancers

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Cancer Biology & Medicine 2020年第4期17卷 864-878页

作者： Klaudia Anna Szymonowicz junjie Chen Department of Experimental Radiation Oncology The University of Texas MD Anderson Cancer CenterHoustonTX 77030USA

Cancer-related diseases represent the second overall cause of death *** papilloma virus(HPV)is an infectious agent which is mainly sexually transmitted and may lead to HPV-associated cancers in both men and *** all cervical cancers are HPV-associated,however,an increasing number of head and neck cancers(HNCs),especially oropharyngeal cancer,can be linked to HPV ***,anogenital cancers,including vaginal,vulvar,penial,and anal cancers,represent a subset of HPVrelated *** testing and prevention of cervical cancer have significantly improved over past decades,anogenital cancers remain more difficult to *** clinical trials including patients with HPV-related cancers focus on finding proper testing for all HPV-associated cancers as well as improve the currently applied *** HPV viral oncoproteins,E6 and E7,lead to degradation of,respectively,p53 and pRb resulting in entering the S phase without G1 *** high-risk HPV viral oncogenes alter numerous cellular processes,including DNA repair,angiogenesis,and/or apoptosis,which eventually result in ***,a comprehensive analysis of gene expression and alteration among a panel of DNA double strand breaks(DSB)repair genes in HPV-negative and HPV-positive HNC cancers reveals differences pointing to HPV-dependent modifications of DNA repair processes in these *** this review,we discuss the current knowledge regarding HPV-related cancers,current screening,and treatment options as well as DNA damage response-related biological aspects of the HPV infection and clinical trials.

关键词： Human papillomavirus(HPV) cervical cancer HNC DNA repair clinical trials cancer statistics

When pressure meets light: detecting the photoacoustic effect at the origin

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Light(Science & Applications) 2017年第1期6卷 390-391页

作者： junjie Yao Photoacoustic Imaging Laboratory Department of Biomedical EngineeringDuke UniversityDurhamNC 27708USA

Modern optical microscopy1,including confocal microscopy,twophoton microscopy and optical coherence tomography(OCT),has revolutionized life sciences by providing detailed information of biological samples with cellular and subcellular resolutions,and has become an essential tool for biomedical research ***,optical microscopy typically has a limited penetration depth of~1 mm in biological tissue due to strong optical scattering2,***,with respective contrast mechanisms,confocal and two-photon microscopy usually rely on fluorescent labeling of the samples and OCT still lacks sensitivity to many biological *** contrast,optical-resolution photoacoustic microscopy(OR-PAM)has emerged over the last decade as a complementary imaging tool to the existing optical microscopy by taking advantage of its unique optical absorption *** acoustically detecting the optical absorption in the tissue,OR-PAM has been proven a powerful tool for anatomical,functional and molecular imaging with endogenous or exogenous contrast *** particular,using hemoglobin as the endogenous optical absorber,OR-PAM currently represents the most sensitive blood detector and has been widely used for in vivo imaging of the blood perfusion and oxygenation,especially for cancer and brain ***,the acoustic detection in OR-PAM is a doubleedged sword;on the one hand,it provides a relatively deep penetration with one-way optical attenuation and negligible acoustic attenuation,but on the other hand,the acoustic detection typically needs a coupling medium,such as water and ultrasound gel,between the tissue surface and the ultrasound *** need for acoustic coupling has become one of the major factors that has hindered the wide adoption of OR-PAM by biomedical researchers whenever the biological samples are not compatible with an aquatic ***,contact-free detection of the photoacoustic signals(that is,without the need for acoustic coupling

关键词： typically whenever negligible

LINEAR REGRESSION OF INTERVAL-VALUED DATA BASED ON COMPLETE INFORMATION IN HYPERCUBES

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Journal of Systems Science and Systems Engineering 2012年第4期21卷 422-442页

作者： Huiwen WANG Rong GUAN junjie WU Beijing Key Laboratory of Emergency Support Simulation Technologies for City Operations School of Economics and ManagementBeihang University

Recent years have witnessed an increasing interest in interval-valued data analysis. As one of the core topics, linear regression attracts particular attention. It attempts to model the relationship between one or more explanatory variables and a response variable by fitting a linear equation to the interval-valued observations. Despite of the well-known methods such as CM, CRM and CCRM proposed in the literature, further study is still needed to build a regression model that can capture the complete information in interval-valued observations. To this end, in this paper, we propose the novel Complete Information Method （CIM） for linear regression modeling. By dividing hypercubes into informative grid data, CIM defines the inner product of interval-valued variables, and transforms the regression modeling into the computation of some inner products. Experiments on both the synthetic and real-world data sets demonstrate the merits of CIM in modeling interval-valued data, and avoiding the mathematical incoherence introduced by CM and CRM.

关键词： Interval-valued data linear regression complete information method (CIM) hypercubes

SOCIAL MEDIA RESEARCH:A REVIEW

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Journal of Systems Science and Systems Engineering 2013年第3期22卷 257-282页

作者： junjie WU Haoyan SUN Yong TAN School of Economics and Management Beihang University Michael G.Foster School of Business University of Washington

Social media is fundamentally changing the way people communicate, consume and collaborate. It provides companies a new platform to interact with their customers. In academia, there is a surge in research efforts on understanding its effects. This paper aims to provide a review of current status of social media research. We discuss the specific domains in which the impacts of social media have been examined. A brief review of applicable research methodologies and approaches is also provided.

关键词： social media empirical models experimental methods analytical approaches predictive analytics

Energy consumption of 270 schools in Tianjin, China

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Frontiers in Energy 2015年第2期9卷 217-230页

作者： Jincheng XING junjie CHEN Jihong LING School of Environmental Science and Engineering Tianjin UniversityTianjin 300072 China

With the rapid development of education cause, the increasing energy consumption of school buildings is gradually causing widespread concern in recent years in China. This paper presented an analysis of energy consumption of 270 schools located in the city of Tianjin, China. The analysis focused specifically on calculating the space heating energy consumption indexes and non-heating energy consumption indexes of different types of schools, aiming at providing reliable and precise data for the government to elaborate policies and measures. The space heating energy consumption of schools adopting district heating and gas boiler were 92.04 kWh/（m2. a） and 64.25 kWh/（m2. a）, respectively. Comparing to the schools without a canteen, the non-heating energy consumption index of schools with a canteen can increase by 8%-37%. Furthermore, clustering of different energy sources, the total primary energy consumption indexes were also presented. Space heating energy consumption accounted for approximately 64%-79% of the total primary energy consumption. When using time-sharing control and self- contained gas boiler instead of district heating, an amount of almost 27.8 kWh/（mZ-a） and 77.5 kWh/（m2.a） can be saved respectively. Through extensive statistical analysis of the data collected, this paper demonstrated that gross floor area, heating energy source and canteen had a close relationship with the total primary energy consumption regarding complete schools. Eventually, a linear regression equation was established to make a simple prediction about the total energy consumption of existing complete schools and to estimate the energy consumption of complete schools to be built.

关键词： schools energy consumption index primaryenergy energy saving regression analysis

Component fault diagnosis for nonlinear systems

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Journal of Systems Engineering and Electronics 2016年第6期27卷 1283-1290页

作者： junjie Huang Zhen Jiang Junwei Zhao School of Mechanical and Power Engineering Henan Polytechnic University School of Mechatronics Engineering and Automation Shanghai University

In the field of fault diagnosis, the state equation of nonlinear system, including the actuator and the component, has been established. When the faults in the system appear, it is difficult to observe the fault isolation between the actuator and the component. In order to diagnose the component fault in the nonlinear systems, a novel strategy is proposed. The nonlinear state equation with only the component system is built on mathematical equations. The nonlinearity of the component equation is expanded and estimated with Taylor series. If the actuator is perfect, the anomaly of the state equations reflects the component fault. The fault feature index is defined to detect the component fault and the initial fault. The numerical examples of the component faults are simulated for multiple-input multiple-output(MIMO)nonlinear systems. The results show that the component faults,as well as the incipient faults, can be detected. Furthermore, the effectiveness of the proposed strategy is verified. This method can also provide a foundation for the component fault reconfiguration control.

关键词： multiple-input multiple-output(MIMO) nonlinear systems component faults fault feature index fault diagnosis