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Semiparametric Empirical Likelihood Estimation for Two-stage Outcome-dependent Sampling under the Frame of Generalized Linear Models

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Acta Mathematicae Applicatae Sinica 2014年第3期30卷 663-676页

作者： jie-li DING yan-yan LIU School of Mathematics and Statistics Wuhan University

Epidemiologic studies use outcome-dependent sampling （ODS） schemes where, in addition to a simple random sample, there are also a number of supplement samples that are collected based on outcome variable. ODS scheme is a cost-effective way to improve study efficiency. We develop a maximum semiparametric empirical likelihood estimation （MSELE） for data from a two-stage ODS scheme under the assumption that given covariate, the outcome follows a general linear model. The information of both validation samples and nonvalidation samples are used. What is more, we prove the asymptotic properties of the proposed MSELE.

关键词： biased-sampling two-stage design empirical likelihood generalized linear models large-sample properties.

On the DB gap of white dwarf evolution: effects of hydrogen mass fraction and convective overshooting

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Research in Astronomy and Astrophysics 2010年第3期10卷 266-278页

作者： jie Su yan Li National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

We investigate the spectral evolution of white dwarfs by considering the effects of hydrogen mass in the atmosphere and convective overshooting above the convection zone. Our numerical results show that white dwarfs with MH- 10^-16 MG show the DA spectral type between 46 000 ≤ Teff≤ 26 000 K and the DO or DB spectral type may appear on either side of this temperature range. White dwarfs with MH - 10^-15 M⊙ appear as DA stars until they cool to Teff - 31 000 K; from then on they will evolve into DB white dwarfs as a result of convective mixing. If MH in the white dwarfs is more than 10-14 M⊙, the convective mixing will not occur when Teff 〉 20 000 K, thus these white dwarfs always appear as DA stars. White dwarfs within the temperature range 46 000 ≤ Teff ≤ 31 000 K always show the DA spectral type, which coincides with the DB gap. We notice the importance of the convective overshooting and suggest that the overshooting length should be proportional to the thickness of the convection zone to better fit the observations.

关键词： convection -- stars: evolution -- stars: white dwarfs

Output regulation problem for discrete-time linear time-delay systems by output feedback control

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Control Theory and Technology 2016年第1期14卷 49-56页

作者： Yamin yan jie HUANG Department of Mechanical and Automation Engineering The Chinese University of Hong Kong Shatin Hong Kong.

In this paper, we study the output regulation problem of discrete linear time-delay systems by output feedback control. We have established some results parallel to those for the output regulation problem of continuou... 详细信息

关键词： Output regulation discrete linear systems time-delay

Recent advances in geosynthetic-reinforced retaining Nails for highway applications

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Frontiers of Structural and Civil Engineering 2018年第2期12卷 239-247页

作者： jie HAN yan JIANG Chao XU Department of Civil Environmental and Architectural Engineering University of Kansas Lawrence KS 66044 USA Terracon Consultants Inc. 2201 Rowland Ave Savannah Georgia 31404 USA Department of Geotechnical Engineering College of Civil Engineering Tongji University Shanghai 200092 China

Geosynthetic-reinforced retaining （GRR） walls have been increasingly used to support roadways and bridge abutments in highway projects. In recent years, advances have been made in construction and design of GRR walls for highway applications. For example, piles have been installed inside GRR walls to support bridge abutments and sound barrier walls. Geosynthetic layers at closer spacing are used in GRR walls to form a composite mass to support an integrated bridge system. This system is referred to as a geosynthetic-reinforced soil （GRS）-integrated bridge systems （IBS） or GRS-IBS. In addition, short geosynthetic layers have been used as secondary reinforcement in a GRR wall to form a hybrid GRR wall （HGRR wall） and reduce tension in primary reinforcement and facing deflections. These new technologies have improved performance of GRR walls and created more economic solutions; however, they have also created more complicated problems for analysis and design. This paper reviews recent studies on these new GRR wall systems, summarizes key results and findings including but not limited to vertical and lateral earth pressures, wall facing deflections, and strains in geosynthetic layers, discusses design aspects, and presents field applications for these new GRR wall systems.

关键词： bridge geosynthetic highway reinforced wall

P2Y1R is involved in visceral hypersensitivity in rats with experimental irritable bowel syndrome

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World Journal of Gastroenterology 2017年第34期23卷 6339-6349页

作者： jie Wu yan Cheng Rong Zhang Dong Liu Yu-mei Luo Kun-lun Chen Song Ren Jun Zhang Department of Gastroenterology The Second Affiliated Hospital of School of MedicineXi’an Jiaotong University Department of Gastroenterology Shaanxi Provincial People’s Hospital Department of Gastroenterology The First Affiliated Hospital of School of MedicineXi’an Jiaotong University Fourth Cadre ward The Second Affiliated Hospital of School of MedicineXi’an Jiaotong University

AIM To evaluate the role of P2Y1 R in visceral hypersensitivity in rats with experimental irritable bowel *** A rat model of irritable bowel syndrome was generated by intra-colonic administration of acetic acid(AA) and assessed by histology and myeloperoxidase(m PO) activity assay. Then P2Y1 R expression in the colonic tissue was detected by Western blot. In order to explore the regulatory role of P2Y1 R in visceral hypersensitivity, an agonist(m RS2365) and an antagonist(m RS2179) of P2Y1 R were intra-colonically administered and effects were tested through a colorectal distension test. The abdominal withdrawal reflex and abdominal electromyography were tested during the course. RESULTS model assessment tests showed an obvious inflammatoryreaction that appeared on the 2^(nd) d after the AA injection, and the inflammatory reaction gradually recovered and almost disappeared on the 7^(th) d. The model finished on day 8 and showed a clear feature of IBS that had no organic lesion. The average expression of P2Y1 R was significantly higher in the AA group than in the na?ve group(0.319 ± 0.02 vs 0.094 ± 0.016, P < 0.001). m RS2365 could effectively raise the colonic hypersensitivity status at intervention doses of 10(AUC value from 0.30 ± 0.089 to 1.973 ± 0.127 mv?s, P < 0.01) and 100 μmol/L(AUC value from 0.290 ± 0.079 to 1.983 ± 0.195 mv?s, P < 0.01); m RS2179 could effectively reduce the hypersensitivity status at intervention dose of 100 μmol/L(from a mean baseline AUC value of 1.587 ± 0.099 mv?s to 0.140 ± 0.089 mv?s, P < 0.0001). Differences between the m RS2179 group(1.88 ± 1.45) and either the m RS2365 group(3.96 ± 0.19) or the combined treatment(m RS2179 and m RS2365) group(3.28 ± 0.11) were significant(P < 0.01).CONCLUSION P2Y1 R plays a regulatory role in visceral hypersensitivity in rats with experimental IBS. Specific antagonists of P2Y1 R may have potential therapeutic value in treating abdominal pain in IBS.

关键词： Irritable bowel syndrome P2Y1 receptor Regulation Therapy visceral hypersensitivity

Complexity estimation of image sequence for automatic target track

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Journal of Systems Engineering and Electronics 2019年第4期30卷 672-683页

作者： WANG Xiaotian ZHANG Kai yan jie School of Astronautics Northwestern Polytechnical University

In the field of automatic target recognition and tracking,traditional image complexity metrics,such as statistical variance and signal-to-noise ratio,all focus on single-frame ***,there are few researches about the complexity of image *** solve this problem,a criterion of evaluating image sequence complexity is ***,to characterize this criterion quantitatively,two metrics for measuring the complexity of image sequence,namely feature space similarity degree of global background(FSSDGB)and feature space occultation degree of local background(FSODLB)are ***,FSSDGB reflects the ability of global background to introduce false alarms based on feature space,and FSODLB represents the difference between target and local background based on feature ***,the feature space is optimized by the grey relational method and relevant features are removed so that FSSDGB and FSODLB are more reasonable to establish complexity of single-frame ***,the image sequence complexity is not a linear sum of the single-frame image *** tracking errors often occur in high-complexity images and the tracking effect of low-complexity images is very *** nonlinear transformation based on median(NTM)is proposed to construct complexity of image *** experimental results show that the proposed metric is more valid than other metrics,such as sequence correlation(SC)and interframe change degree(IFCD),and it is highly relevant to the actual performance of automatic target tracking algorithms.

关键词： complexity of image sequence feature space similarity degree of global background(FSSDGB) feature space occultation degree of local background(FSODLB) grey relational method nonlinear transformation based on median(NTM)

Current status and prospects of terminal guidance laws for intercepting hypersonic vehicles in near space:a review

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2023年第5期24卷 387-403页

作者： Shuangxi LIU Binbin yan Wei HUANG Xu ZHANG jie yan Unmanned System Research Institute Northwestern Polytechnical UniversityXi'an 710072China School of Astronautics Northwestern Polytechnical UniversityXi'an 710072China Science and Technology on Scramjet Laboratory School of Aerospace Science and EngineeringNational University of Defense TechnologyChangsha 410073China

The unique performance advantages of hypersonic vehicles represent a critical challenge for existing defense *** facilitate defensive operations against hypersonic vehicles in near space,this paper systematically discusses both the advantages of these vehicles and the difficulties in intercepting *** on the state-of-the-art terminal guidance laws for intercepting hypersonic vehicles in near space,we examine research progress in the area of single-and multi-interceptor cooperative guidance laws and summarize their advantages and *** also highlight future research directions for developing an effective terminal guidance law for multi-interceptor cooperative interception of hypersonic vehicles,based on four aspects:the information domain,space domain,physical domain,and effect-cost *** findings provide a reference for further research into near-space interceptor terminal guidance technologies.

关键词： Hypersonic vehicles Guidance law Cooperative guidance Near space

Development of a Bionic Hexapod Robot for Walking on Unstructured Terrain

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Journal of Bionic Engineering 2014年第2期11卷 176-187页

作者： He Zhang Yubin Liu jie Zhao jie Chen Jihong yan State Key Lab of Robotics and System Harbin Institute of Technology Harbin 150080 P. R. China

This paper reports the design methodology and control strategy in the development of a novel hexapod robot HITCR-II that is suitable for walking on unstructured terrain. First, the entire sensor system is designed to equip the robot with the perception of external environment and its internal states. The structure parameters are optimized for improving the dexterity of the robot. Second, a foot-force distribution model and a compensation model are built to achieve posture control. The two models are capable of effectively improving the stability of hexapod walking on unstructured terrain. Finally, the Posture Control strategy based on Force Distribution and Compensation （PCFDC） is applied to the HITCR-II hexapod robot. The experimental results show that the robot can effectively restrain the vibration of trunk and keep stable while walking and crossing over the un- structured terrains.

关键词： hexapod robot structure optimization posture control force distribution force compensation

Soil CO_2 Flux in Different Types of Forests Under a Subtropical Microclimatic Environment

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Pedosphere 2014年第2期24卷 243-250页

作者： yan Wen-De XU Wang-Ming CHEN Xiao-Yong TIAN Da-lun PENG Yuan-Ying ZHEN Wei ZHANG Cao XU jie Forest Ecology Program College of Life Science and TechnologyCentral South University of Forestry and Technology National Engineering Laboratory for Applied Forest Ecological Technology in Southern China State Forestry Administration of China Division of Science College of Arts and SciencesGovernors State UniversityUniversity Park Natural Sciences Division College of DuPage

The flux of carbon dioxide （CO2） from soil surface presents an important component of carbon （C） cycle in terrestrial ecosystems and is controlled by a number of biotic and abiotic factors. In order to better understand characteristics of soil CO2 flux （FCO2） in subtropical forests, soil FCO2 rates were quantified in five adjacent forest types （camphor tree forest, Masson pine forest, mixed camphor tree and Masson pine forest, Chinese sweet gum forest, and slash pine forest） at the Tianjiling National Park in Changsha, Hunan Province, in subtropical China, from January to December 2010. The influences of soil temperature （Tsoil）, volumetric soil water content （0soiI）, soil pH, soil organic carbon （SOC） and soil C/nitrogen （N） ratio on soil FCO2 rates were also investigated. The annual mean soil FCO2 rate varied with the forest types. The soil FCO2 rate was the highest in the camphor tree forest （3.53 ± 0.51 μmol m-2 s-I）, followed by, in order, the mixed, Masson pine, Chinese sweet gum, and slash pine forests （1.53 ± 0.25 μmol m-2 sl）. Soil FCO2 rates from the five forest types followed a similar seasonal pattern with the maximum values occurring in summer （July and August） and the minimum values during winter （December and January）. Soil FCO2 rates were correlated to Tsoil and 0soil, but the relationships were only significant for Tsoil. No correlations were found between soil FCO2 rates and other selected soil properties, such as soil pH, SOC, and C/N ratio, in the examined forest types. Our results indicated that soil FCO2 rates were much higher in the evergreen broadleaved forest than coniferous forest under the same microclimatic environment in the study region.

关键词： broadleaved forest carbon coniferous forest soil temperature soil water content