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Busemann–Petty Problems for General L_p-Intersection Bodies

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Acta Mathematica Sinica,English Series 2015年第5期31卷 777-786页

作者： wei dong wang Ya Nan LI Department of Mathematics China Three Gorges University

For 0 〈 p 〈 1, Haberl and Ludwig defined the notions of symmetric Lp-intersection body and nonsymmetric Lp-intersection body. In this paper, we introduce the general Lp-intersection bodies. Furthermore, the Busemann... 详细信息

关键词： General Lp-intersection body Busemann-Petty problem

Frame rate up-conversion using multiresolution critical point filters with occlusion refinement

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第12期9卷 1621-1630页

作者： Yi-xiong ZHANG wei-dong wang Peng LIU Qing-dong YAO Department of Information Science and Electronic Engineering Zhejiang University Hangzhou 310027 China

In this paper, multiresolution critical-point filters （CPFs） are employed to image matching for frame rate up-conversion （FRUC）. By CPF matching, the dense motion field can be obtained for representing object motions accurately. However, the elastic motion model does not hold in the areas of occlusion, thus resulting in blur artifacts in the interpolated frame. To tackle this problem, we propose a new FRUC scheme using an occlusion refined CPF matching interpolation （ORCMI）. In the proposed approach, the occlusion refinement is based on a bidirectional CPF mapping. And the intermediate frames are generated by the bidirectional interpolation for non-occlusion pixels combined with unidirectional projection for the occlusion pixels. Ex- perimental results show that ORCMI improves the visual quality of the interpolated frames, especially at the occlusion regions. Compared to the block matching based FRUC algorithm, ORCM1 can achieve 1-2 dB PSNR gain for standard video sequences.

关键词： Frame rate up-conversion Multiresolution critical-point filters Occlusion refinement

Kinematics/Fuzzy Logic Combined Controller for Formation Control of Mobile Robots

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Journal of Harbin Institute of Technology(New Series) 2013年第4期20卷 121-128页

作者： Zhi-Jiang Du Li-Min Ren wei-dong wang wei dong State Key Laboratory of Robotics and System Harbin Institute of Technology College of Mechanical Engineering Beihua University

A kinematics and fuzzy logic combined formation controller was proposed for leader-follower based formation control using backstepping method in order to accommodate the dynamics of the *** kinematics controller generates desired linear and angular velocities for follower robots,which make the configuration of follower robots coverage to the *** fuzzy logic controller takes dynamics of the leader and followers into consideration,which is built upon Mamdani fuzzy *** force and torque acting on robots are described as linguistic variables and also 25 if-then rules are *** addition,the fuzzy logic controller adopts the Centroid of Area method as defuzzification strategy and makes robots’actual velocities converge to the expected which is generated by the kinematics *** innovation of the kinematics and fuzzy logic combined formation controller presented in the paper is that the perfect velocity tracking assumption is removed and realtime performance of the system is *** with traditional torque-computed controller,the velocity error convergence time in case of the proposed method is shorter than traditional torque-computed *** simulation results validate that the proposed controller can drive robot members to form the desired formation and formation tracking errors which can coverage to a neighborhood of the ***,the simulations also show that the proposed method has better velocity convergence performance than traditional torque-computed method.

关键词： kinematics/fuzzy logic combined formation controller mobile robot backstepping

Video coding using geometry based block partitioning and reordering discrete cosine transform

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第1期13卷 71-82页

作者： Yi-xiong ZHANG Jiang-hong SHI wei-dong wang Department of Communication Engineering Xiamen University Xiamen 361005 China Department of information Science and Electronic Engineering Zhejiang University Hangzhou 310027 China

Geometry based block partitioning （GBP） has been shown to achieve better performance than the tree structure based block partitioning （TSBP） of H.264. However, the residual blocks of GBP mode after motion compensation still present some non-vertical/non-horizontal orientations, and the conventional discrete cosine transform （DCT） may generate many high-frequency coefficients. To solve this problem, in this paper we propose a video coding approach by using GBP and reordering DCT （RDCT） techniques. In the proposed approach, GBP is first applied to partition the macroblocks. Then, before performing DCT, a reordering operation is used to adjust the pixel positions of the residual macroblocks based on the partition information. In this way, the partition information of GBP can be used to represent the reordering information of RDCT, and the bitrate can be reduced. Experimental results show that, compared to H.264/AVC, the proposed method achieves on average 6.38% and 5.69% bitrate reductions at low and high bitrates, respectively.

关键词： Geometry based block partitioning Reordering DCT Motion compensation Video coding

Capacity of FH wireless multi-hop networks

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The Journal of China Universities of Posts and Telecommunications 2009年第6期16卷 78-83页

作者： wei dong-yan wang Wen-bo PENG Mu-gen Key Laboratory of Universal Wireless Communication Ministry of Education Beij hag University of Posts and Telecommunications Beijing 100876 China

In this article,the capacity of wireless multi-hop networks with the frequency hopping（FH） technique is *** from the previous work based on non-spread spectrum（SS） system,this study is based on frequency hopping spread spectrum（FHSS） and the retransmission *** analysis results show that the normalized transport capacity decreases as 1/Mλ,when the total available frequency band is divided into M sub-bands for frequency hopping and the nodes are randomly distributed in space according to a Poisson point process with intensity λ .In this work,the best transmission range per hop to get the maximum capacity is also ***,the results summarize how the capacity of FH wireless multihop networks is affected by the outage probability,target signal to interference plus noise ratio（SINR） and other system parameters.

关键词： multihop frequency hopping capacity

Synthesis,Biological Evaluation and Molecular Modeling of Cyclic Tetrapeptide Based Inhibitors HDAC

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Chemical Research in Chinese Universities 2012年第6期28卷 1011-1016页

作者： LI Xiao-hui wei Ying-dong wang Shi-miao wang Meng-nan HUANG Da-wei XIU Zhi-long School of Life Science and Biotechnology Dalian University of Technology Dalian 116024 P. R. China

Histone deacetylases（HDACs） are considered to be among the most promising targets for the development of anti-cancer drugs,and HDAC inhibitors（HDACIs） have become a promising class of anti-cancer *** explore whether thioacetyl group as the zinc binding group（ZBG） and a slight change in the hydrophobicity of the recognition domain of HDACIs could alter their activities,we synthesized a series of cyclo[-L-Am7（SAc）-Aib-L-Phe（n-Cl）D-Pro-] and evaluated their HDAC-inhibitory and antiproliferative *** results show that these peptides could inhibit HDAC at 10-9 mol/L level,and could selectively inhibit the proliferation of three human cancer cell lines with IC 50 at 10-6 mol/L *** study was conducted to examine the mechanisms by which these peptides interact with *** appeared that a zinc ion in the active site of HDAC was coordinated by the carbonyl oxygen atom of the ZBG in the *** the ZBG domain of all the peptides and the surface recognition domain of cyclo[-L-Am7（SAc）-Aib-L-Phe（o-Cl）-D-Pro-] and that of cyclo[-L-Am7（SAc）-Aib-L-Phe（m-Cl）-D-Pro-] interacted with HDAC2 via hydrogen *** interaction has been considered to provide favorable contributions to stabilizing the complexes,and the introduction of a chlorine atom at the aromatic ring on the L-Phe position of these peptides affected the interaction between each of these inhibitors and the enzyme,resulting in slight change in the structure of the surface recognition domain of the peptides.

关键词： Histone deacetylase(HDAC) Histone deacetylase inhibitor(HDACI) Cyclic tetrapeptide Anti-cancer agent Antiproliferative activity Docking

Acute pancreatitis:Etiology and common pathogenesis

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World Journal of Gastroenterology 2009年第12期15卷 1427-1430页

作者： Guo-Jun wang Chun-Fang Gao dong wei Cun wang Si-Qin Ding Institute of Digestive Surgery and Department of General Surgery 150 Hospital of Chinese PLA Gaoxin District Luoyang 471031 Henan Province China

Acute pancreatitis is an inflammatory disease of the *** etiology and pathogenesis of acute pancreatitis have been intensively investigated for centuries *** causes of acute pancreatitis have been discovered,but the pathogenetic theories are *** most common cause of acute pancreatitis is gallstone impacting the distal common bile-pancreatic *** majority ofinvestigators accept that the main factors for acute billiary pancreatitis are pancreatic hyperstimulation and bile-pancreatic duct obstruction which increase pancreatic duct pressure and active trypsin *** pancreatitis occurs when intracellular protective mechanisms to prevent trypsinogen activation or reduce trypsin activity are ***,little is known about the other acute *** hypothesize that acute biliary pancreatitis and other causes of acute pancreatitis possess a common *** hyperstimulation and pancreatic duct obstruction increase pancreatic duct pressure,active trypsin reflux,and subsequent unregulated activation of trypsin within pancreatic acinar *** activation within the pancreas leads to auto-digestion of the gland and local *** the hypothesis is confirmed,traditional therapeutic strategies against acute pancreatitis may be *** of pancreatic duct pressure should be advocated in the treatment of acute pancreatitits which may greatly improve its outcome.

关键词： Acute pancreatitis Pathogenesis Etiology Pancreatic duct obstruction Pancreatichyperstimulation Pancreatic duct pressure

Effect of amide type modified rapeseed oil as lubricating additive on friction and wear behavior of steel-steel and steel-aluminum alloy systems

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 435-438页

作者： FANG Jian-hua CHEN Bo-shui LIU wei-min dong Lin wang Jiu Department of Petrochmistry Logistical Engineering University Chongqing 400016 China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China Department of Petrochmistry Logistical Engineering University Chongqing 400016 China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China Department of Petrochmistry Logistical Engineering University Chongqing 400016 China Department of Petrochmistry Logistical Engineering University Chongqing 400016 China

A new type of environmentally friendly lube additive-amide type modified rapeseed oil was synthesized and characterized by infrared spectrum. Its effect on the friction and wear behavior of steel-steel and steel-aluminum alloy systems were investigated with a four-ball machine and an Optimol SRV friction and wear tester *** morphographies of the worn surfaces were analyzed by means of scanning electron microscopy(SEM). The worn surfaces of the 2024Al alloy block were analyzed by means of X-ray photoelectron spectroscopy(XPS). The results show that the modified rapeseed oil as additives can obviously decrease the wear rate and friction coefficient of steel pair and steel-aluminum frictional pair. Its lubrication mechanism is inferred that a high strength complex protection films form on the worn surface of the Al alloy due to the adsorption or tribochemistry reaction of a long chain additive molecule and high reaction activity of N element.

关键词： environmentally friendly lube additive amide type rapeseed oil steel-steel pair steel-aluminum alloy pair tribochemistry

Low central venous pressure reduces blood loss in hepatectomy

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World Journal of Gastroenterology 2006年第6期12卷 935-939页

作者： wei-dong wang Li-Jian Liang Xiong-Qing Huang Xiao-Yu Yin Department of General Surgery The FirstPeople's Hospital of Shun De Fuoshan 528300 GuangdongProvince China Department of Hepatobiliary Surgery The First Affiliated Hospital Sun Yat-Sen University Guangzhou510080 Guangdong Province China Department of Anaesthesia The FirstAffiliated Hospital Sun Yat-Sen University Guangzhou 510080Guangdong Province China

AIM： To investigate the effect of low central venous pressure （LCVP） on blood loss during hepatectomy for hepatocellular carcinoma （HCC）. METHODS： By the method of sealed envelope, 50 HCC patients were randomized into LCVP group （n=25） and control group （n=25）. In LCVP group, CVP was maintained at 2-4 mmHg and systolic blood pressure （SBP） above 90 mmHg by manipulation of the patient＇s posture and administration of drugs during hepatectomy, while in control group hepatectomy was performed routinely without lowering CVP. The patients＇ preoperative conditions, volume of blood loss during hepatectomy, volume of blood transfusion, length of hospital stay, changes in hepatic and renal functions were compared between the two groups. RESULTS： There were no significant differences in patients＇ preoperative conditions, maximal tumor dimension, pattern of hepatectomy, duration of vascular occlusion, operation time, weight of resected liver tissues, incidence of post-operative complications, hepatic and renal functions between the two groups. LCVP group had a markedly lower volume of total intraoperative blood loss and blood loss during hepatectomy than the control group, being 903.9 ± 180.8 mL vs 2 329.4 ±2 538.4 （W=495.5, P〈0.01） and 672.4±429.9 mL vs 1 662.6±1 932.1 （W=543.5, P〈0.01）. There were no remarkable differences in the pre-resection and post-resection blood losses between the two groups. The length of hospital stay was significantly shortened in LCVP group as compared with the control group, being 16.3±6.8 d vs 21.5 ± 8.6 d （W= 532.5, P〈0.05）.CONCLUSION： LCVP is easily achievable in technique. Maintenance of CVP ≤4 mmHg can help reduce blood loss during hepatectomy, shorten the length of hospital stay, and has no detrimental effects on hepatic or renal function.

关键词： Hepatectomy Hepatocellular carcinoma Central venous pressure Blood loss