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Chinese Journal of Aeronautics 2010年第6期23卷 707-714页

作者： ZhuYongguo Huang xiang fang Wei Li Shuanggao Department of Mechanical and Electrical Engineering Nanjing University of A eronautics and Astronautics Nanjing 210016 China Aeronautical Manufacturing Technology Institute Shanghai Aircraft Manufacturing Co. Ltd. Shanghai 200436 China

A 6-degree of freedom （6-DOF） aircraft wing position and pose automatic adjustment method is presented to improve ARJ21 wing-fuselage connection precision and efficiency. Wing position and pose are adjusted by three pillars which are driven by six high-precision servo motors. During the adjustment process, wing is tracked and positioned by laser tracker. Wing initial position and pose are calibrated by using the measurement coordinates of assembly reference points. Wing target position and pose are calculated according to wing initial, fuselage position and pose, and relative position and pose requirements between wing and fuselage for the connection. Combining Newton-Euler method with quaternion position and pose analyzing method, the inverse kinematics of servo motors, together with the adjustment system dynamics is obtained. Wing quintic polynomial trajectory planning algorithm based on quatemion is proposed; the initial, target position and pose need to be solved and the intermediate moving path is uncertain. Simulation results show that the adjustment method has good dynamic characteristics and satisfies engineering requirements. Preliminary engineering application indicates that ARJ21 wing adjustment efficiency and precision are improved by using the proposed method.

关键词： aircraft assembly calibration position and pose adjustment trajectory planning quaternion

A maximum a posteriori super resolution algorithm based on multidimensional Lorentzian distribution

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第12期10卷 1705-1713页

作者： Wen CHEN xiang-zhong fang Yan CHENG Shanghai Key Lab of Digital Media Processing and Transmissions Institute of Image Communication and Information Processing Shanghai Jiao Tong University Shanghai 200240 China College of Information Technology East China University of Political Science and Law Shanghai 201620 China

This paper presents a threshold-free maximum a posteriori (MAP) super resolution (SR) algorithm to reconstruct high resolution (HR) images with sharp edges. The joint distribution of directional edge images is modeled as a multidimensional Lorentzian (MDL) function and regarded as a new image prior. This model makes full use of gradient information to restrict the solution space and yields an edge-preserving SR algorithm. The Lorentzian parameters in the cost function are replaced with a tunable variable, and graduated nonconvexity (GNC) optimization is used to guarantee that the proposed multidimensional Lorentzian SR (MDLSR) algorithm converges to the global minimum. Simulation results show the effectiveness of the MDLSR algorithm as well as its superiority over conventional SR methods.

关键词： Edge preservation Multidimensional Lorentzian distribution (MDL) Super resolution Threshold

Decadal-to-interdecadal response and adjustment of the North Pacific to prescribed surface forcing in an oceanic general circulation model

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Acta Oceanologica Sinica 2006年第3期25卷 11-24页

作者： fang Jiabei rong Xinyao YANG Xiuqun Institute of Severe Weather ＆ Climate Nanjing University Nanjing 210093 China

The simulation of a higher-resolution oceanic GCM forced with COADS surface conditions during 1945 ～ 1993 was analyzed with insight into how the North Pacific responds to the surface forcing. The decadal-to-interdecadal variabilities in the thermal and dynamical fields especially those associated with the 1976/1977 regime shift in the North Pacific were investigated. The model successfully captures the dominant SST anomaly mode on the decadal-to-interdecadal time scales as well as the major feature of SST anomalies in the 1976/1977 regime shift. The model also successfully reproduces two typical subduction events that link the tropical and extratropical oceanic temperature anomalies during the 1970s and the 1980s. Most importantly, the model simulates the dynamical adjustment of the upper ocean under the surface wind forcing. The typical surface circulation anomaly is characterized by a pattern that is simultaneously related to the wind stress anomalies. The typical anomalous pattern for the entire upper-ocean is characterized by coherent anomalies of two oceanic gyres, i.e. , the subtropical and subpolar gyres. The delayed response and slower adjustment of the gyres, especially of the subpolar gyre, give rise to a persistent SST anomaly in the central North Pacific. The upper-ocean heat budgets in three target regions, i.e. , the central North Pacific, the Californian coastal region and the KOE region, are examined. The cooling in the central North Pacific around 1976/1977 is attributed to the heat flux and mefidional advection anomalies. The associated warming in the Californian coastal region is only due to the heat flux anomaly. A cooling shift in the KOE region which lags that in the central basin by 3 to 4 a is largely due to the meridional advection anomaly and the heat flux acts only as a damping role.

关键词： North Pacific Ocean decadal-to-interdecadal variability subtropical gyre subpolar gyre

Some remarks on Wente's inequality and the Lorentz-Sobolev space

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Applied Mathematics(A Journal of Chinese Universities) 2016年第3期31卷 355-361页

作者： ZHU xiang-rong CHEN Jie-cheng Department of Mathematica Zhejiang Normal University

In this note we consider Wente＇s type inequality on the Lorentz-Sobolev space. If f∈L^p1,q1（Rn）,G∈L^p2,q2 （Rn） and div G ≡ 0 in the sense of distribution where 1/p1＋1/p2=1/q ＋1/q2=1,1〈p1,p2〈∞, it is known that G. f belongs to the Hardy space H1 and furthermore ‖G· f‖N1≤C‖ f‖Lp1,q1（R2）‖G‖Lp2,q2（R2）Reader can see [9] Section 4 Here we give a new proof of this result. Our proof depends on an estimate of a maximal operator on the Lorentz space which is of some independent interest. Finally, we use this inequality to get a generalisation of Bethuel＇s inequality.

关键词： Lorentz space Wente type inequality Hardy space

Inductive Rings and Systems of Diophantine Equations

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Acta Mathematica Sinica,English Series 2006年第5期22卷 1549-1556页

作者： rong fang BIE Shi Qiang WANG College of Information Science Beijing Normal University Beijing 100875 P. R. China School of Mathematical Sciences Beijing Normal University Beijing 100875 P. R. China

In this paper, by using model-theoretic methods, it is shown that some systems of unsolved cubic diophantine equations in number theory can have solutions in certain inductive extension rings of the ring I of rational integers. These inductive rings are not fields, and every element of them is a sum of 4 cubes and a sum of 3 squares. Also some of them satisfy the Goldbach conjecture and some others don＇t.

关键词： Inductive rings Systems of unsolved cubic diophantine equations Model theory

Nonlinear Instability of Phillips Model

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Acta Mathematicae Applicatae Sinica 2016年第3期32卷 669-684页

作者： rong-fang WANG Hong-jun GAO Jiangsu Provincial Key Laboratory for Numerical Simulation of Large Scale Complex Systems School of Mathematical Sciences Nanjing Normal University Institution of Mathematics Jilin University

We investigate the instability of two-layer Phillips model in this paper, which is a prototypical geophysical fluid model. Using the results of Guo and Strauss et al, we obtained linear instability implies nonlinear i... 详细信息

关键词： nonlinear instability Lyapunov exponent Phillips model

Intracellular Retention of Human Melanocortin-4 Receptor:A Molecular Mechanism Underlying Early-onset Obesity in F261S Pedigree of Chinese

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Biomedical and Environmental Sciences 2008年第4期21卷 280-285页

作者： QI-CHEN fang WEI-PING JIA SHU-BING CAI XIN-YU SHAO rong ZHANG CONG-rong WANG YU-QIAN BAO KUN-SAN xiang Department of Endocrinology and Metabolism Shanghai Sixth People’s Hospital Affiliated to Shanghai Jiaotong UniversityShanghai Diabetes InstituteShanghai Clinical Center of DiabetesShanghai 200233China

Objective To investigate how F261S mutation identified from Chinese obese patients affects the function of melanocorfin 4 receptor (MC4R) and to analyze the obesity-related phenotypes in subjects carrying the F261S mutation. Methods F261S mutant of MC4R was generated by site-directed mutagenesis. Plasmids encoding wild-type or F261S mutant of MC4R were transfected into HEK293 and COS-7 cells to examine their functional characteristics. Signaling properties of F261S MC4R were assessed by measuring intracellular cAMP levels in response to α-MSH stimulation. Cell surface expression of F261S MC4R was compared with that of wild-type MC4R. Clinical examinations were performed in subjects carrying F261S mutation and in non-mutated controls. Results The a-MSH-stimulated reporter gene activity was significantly reduced in cells expressing F261S MC4R, with a maximal response equal to 57% of wild-type MC4R. The F261S mutation also led to a significant change in the EC50 value compared with the wild-type receptor (P〈0.01). Immunofluorescent assay revealed a marked reduction in plasma membrane localization of the MC4R in cells expressing the F261S mutant receptor. The resting metabolic rate and fat composition of the mutant carriers were not significantly different from those of the non-mutated obese controls. Conclusions The decreased response to α-MSH due to the intracellular retention of MC4R may cause early-onset obesity in the F261S pedigree of Chinese.

关键词： Obesity Melanocortin 4 receptor Mutation Chinese

Detecting protein complexes from DPINs by density based clustering with Pigeon-Inspired Optimization Algorithm

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Science China(Information Sciences) 2016年第7期59卷 30-43页

作者： Xiujuan LEI Yulian DING fang-xiang WU School of Computer Science Shaanxi Normal University School of Mathematical Sciences Nankai University Division of Biomedical Engineering University of Saskatchewan

Detecting protein complexes is crucial to understand principles of cellular organization. Plenty evidences have indicated that sub-graphs with high density in protein-protein interaction(PPI) network, especially dynamic PPI network(DPIN), usually correspond to protein complexes. As a well-known density-based clustering algorithm, Density-Based Spatial Clustering of Applications with Noise(DBSCAN) has been used in many areas due to its simplicity and the ability to detect clusters of different sizes and shapes. However, one of its limitations is that the performance of DBSCAN depends on two specified parameters ε and Min Pts, where εrepresents the maximum radius of a neighborhood from an observing point while Min Pts means the minimum number of data points contained in such a neighborhood. In this article, we develop a new method named as P-DBSCAN to detect protein complexes in DPIN by using Pigeon-Inspired Optimization(PIO) Algorithm to optimize the parameters ε and Min Pts in DBSCAN. The experiments on DIP and MIPS datasets show that P-DBSCAN outperforms the state-of-the-art methods for protein complex detection in terms of several criteria such as precision, recall and f-measure.

关键词： dynamic protein-protein interaction network(DPIN) pigeon-inspired optimization(PIO) protein complex density based clustering gene expression

Analysis and control for a bioinspired multi-legged soft robot

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Biomimetic Intelligence & Robotics 2022年第1期2卷 22-28页

作者： Danying Sun Jingyu Zhang Qin fang Pingyu xiang Yanan Xue Yue Wang rong Xiong Haojian Lu State Key Laboratory of Indusrial Control and Technology Zhejiang UniversityHangzhou 310027China Instiute of Cyber-Systerms and Corntrol the Department of Cororol Science and Engineoring Zhejiang Universiy Hangzhou 310027China Deparmernt of Plastic Surgery Sir Run Run Shaw HospitalZhejiang University of MedicineHanghou 310016China

Untethered soft miniature robots are considered to have a wide range of applications in biomedical ***,researchers today still have not reached a consensus on its configuration design and actuation ***,inspired by the tentacles of a certain kind of echinodermata,we propose a soft multi-legged robot with a total weight of 0.26 g capable of multiple locomotion *** on the magnetic field distribution of a square permanent magnet,we qualitatively analyze the motion mechanism of the ***,we carried out relevant experimental *** research shows that the robot can move forward,backward,steering and cross obstacles under the control of the magnetic field,and can combine these abilities to navigate the maze.

关键词： Multi-legged soft robot Magnetic modeling Magnetic control Multi-legged robot locomotion

A Note on Certain Block Spaces on the Unit Sphere

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Acta Mathematica Sinica,English Series 2006年第6期22卷 1843-1846页

作者： Xiao Feng YE xiang rong ZHU Department of Mathematics (Xixi Campus) Zhejiang University Hangzhou 310028 P. R. China

In this note, we clarify a relation between block spaces and the Hardy space. We obtain Bq^0.v belong to H^1（S^n-1）＋L（ln＋L）^1＋v（s^n-1）,v〉-1,q〉1,Furthermore,if v≥ 0, q 〉 1. we verify that block spaces Rq... 详细信息

关键词： block spaces Hardy space