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Effects of reconfiguration on the performance of mobile navigation robot

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High Technology Letters 2006年第3期12卷 245-249页

作者：付宜利 Xu He li han wang Shuguo Ma Yuliu Advanced Manufacturing Technology Center Harbin Institute of Technology Harbin 150001 P. R. China

An irmovative mobile robot that has reconfigurable loeomotion chassis and reconfigurable bionic wheels has been developed to meet the needs of different payload and different terrain. Several prototypes have been achieved by the recortfiguration. By modeling relative comparison coefficients, these prototypes are analyzed in terms of geometrical parameter of trafficability, static stability and maneuverability. The effects of reconfiguration on these indices of robot performance can be compared, i.e. the variable height of chassis h has the biggest effect, the variable length of chassis 1 is the second, then is the camber angle β and the caster angle α. Some principles for reconfiguration are proposed.

关键词： reconfigurable chassis reconfigurable bionic wheel comparative coefficient mobile navigation robot

JACOBI SPECTRAL METHODS FOR MULTIPLE- DIMENSIONAL SINGULAR DIFFERENTIAL EQUATIONS

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Journal of Computational Mathematics 2003年第3期21卷 325-338页

作者： li-han wang Ben-yu Guo (Department of Mathematics, Shanghai Normal University, Shanghai 200234, China) Department of Mathematics Shanghai Normal University 上海 200234

Jacobi polynomial approximations in multiple dimensions are investigated. They are applied to numerical solutions of singular differential equations. The convergence analysis and numerical results show their advantages.

关键词： Jacobi approximations Multiple dimensions.

Hepatitis C viral infection in a Chinese hemodialysis unit

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Chinese Medical Journal 2010年第24期123卷 3574-3577页

作者： li han wang Shi-xiang Blood Purification Center Beijing Chaoyang Hospital Capital Medical University Beijing 100020 China

Background The prevalence of hepatitis C virus （HCV） infection among maintenance hemodialysis （MHD） patients varies among countries and among dialysis units within a single country. The present study aimed to investigate the prevalence and characteristics of HCV infection in MHD patients in a Chinese hemodialysis *** One hundred and ninety-two patients on MHD for an average of （86.1±30.0） months （range 6-181 months） were enrolled in this cross-sectional study. HCV antibody and HCV-RNA were measured in these MHD patients before hemodialysis by enzyme-linked immunosorbent assay （EliSA） and polymerase chain reaction （PCR） *** to the result, all the patients were then divided into two groups： GroupⅠwas positive for HCV antibody and/or HCV-RNA （n=32）, and Group Ⅱ was negative for HCV antibody and HCV-RNA （n=160）. The following information was obtained for all the patients： socio-demographic data, history of blood transfusions and kidney transplantation, and some laboratory values. The MHD patients who were positive for HCV antibody and/or HCV-RNA were followed for more than three years. The disease activities were graded into ＂asymptomatic＂ if alanine aminotransferase （ALT） was less than 40 U/L,＂low activities＂ if ALT was 40-79 U/L, and ＂high activities＂ if ALT was equal to or above 80 U/*** The prevalence of HCV infection in MHD patients in our dialysis unit in May 2009 was 16.7, which was significantly higher than in general population （3.2%）. Among the 32 MHD patients with HCV positive, 20 patients were positive for HCV antibody but negative for HCV-RNA, eight patients were positive both for HCV antibody and HCV-RNA,four patients were negative for HCV antibody but positive for HCV-RNA. Eleven patients had a history of kidney transplantation and 12 had a history of blood transfusion, which were significantly more than among the MHD patients without HCV. Thirty of the 32 MHD patients were asymptomatic. There were no significant differences i

关键词： hepatitis C virus infection hemodialysis

Oscillator strength study of the excitations of valence-shell of C2H2 by high-resolution inelastic x-ray scattering

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Chinese Physics B 2022年第5期31卷 261-264页

作者： Qiang Sun Ya-Wei liu Yuan-Chen Xu li-han wang Tian-Jun li Shu-Xing wang Ke Yang lin-Fan Zhu Hefei National Research Center for Physical Sciences at Microscale and Department of Modern Physics University of Science and Technology of ChinaHefei 230026China Anhui Province Key Laboratory of Medical Physics and Technology Institute of Health and Medical TechnologyHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230026China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China

The oscillator strengths of the valence-shell excitations of C_(2)H_(2) are extremely important for testing theoretical models and studying interstellar *** this study,the high-resolution inelastic x-ray scattering(IXS)method is adopted to determine the generalized oscillator strengths(GOSs)of the valence-shell excitations of C_(2)H_(2) at a photon energy of10 ke *** GOSs are extrapolated to their zero limit to obtain the corresponding optical oscillator strengths(OOSs).Through taking a completely different experimental method of the IXS,the present results offer the high energy limit for electron collision to satisfy the first Born approximation(FBA)and cross-check the previous experimental and theoretical results *** comparisons indicate that an electron collision energy of 1500 e V is not enough for C_(2)H_(2) to satisfy the FBA for the large squared momentum transfer,and the line saturation effect limits the accuracy of the OOSs measured by the photoabsorption method.

关键词： C_(2)H_(2) inelastic x-ray scattering dynamic parameters

Mixed State and High Effective Utilization of Pilbara Blending Iron Ore Powder

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Journal of Iron and Steel Research International 2011年第9期18卷 1-5页

作者： CAO Yong-guo WU Sheng-li han Hong-liang wang Hong-wei XUE Fang liU Xiao-qin School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China

Pilbara blending iron ore powder （PB powder） is blending ores with good and poor quality iron ores, so how to use PB power effectively is a problem. The self-characteristics of PB powder and its single-components were studied respectively such as the macroscopic properties, microscopic properties, and high-temperature properties the behavior and effect in the sintering were mastered. Then based on the new ore-proportioning idea of iron ores sintering characteristics complementary, the principles on the effective use of PB powder were discussed, and was fur ther validated through the sintering pot test and industrial production. The results show that PB powder is composed of three kinds of iron ore, and the sintering characteristics of different iron ores are obviously discrepant. With the ore-proportioning optimization based on the iron ores sintering characteristics complementary, the proportion of PB iron ore powder can be increased to more than 45 %.

关键词： Pilbara blending ore sintering mixed state high effective utilization

Ascending aortic dilatation rate after transcatheter aortic valve replacement in patients with bicuspid and tricuspid aortic stenosis: A multidetector computed tomography follow-up study

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World Journal of Emergency Medicine 2019年第4期10卷 197-204页

作者： Yu-xin He Jia-qi Fan Qi-feng Zhu Qi-jing Zhou Ju-bo Jiang li-han wang Stella Ng Xian-bao liu Jian-an wang Department of Cardiology the Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310009China Department of Radiology the Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310009China

BACKGROUND: Current data is lacking about the progression of ascending aortic dilatation after transcatheter aortic valve replacement(TAVR) in aortic stenosis(AS) patients with bicuspid aortic valve(BAV) and tricuspid aortic valve(TAV). This study aims to assess the ascending aortic dilatation rate(mm/year) after TAVR in patients with BAV versus TAV using a multidetector computed tomography(MDCT) fol ow-up and to determine the predictors of ascending aortic dilatation ***: Severe AS patients undergoing TAVR from March 2013 to March 2018 at our center with MDCT follow-ups were included. BAV and TAV were identified using baseline MDCT. Baseline and follow-up MDCT images were analyzed,and the diameters of ascending aorta were measured. Study end point is ascending aortic dilatation rate(mm/year). Furthermore,factors predicting ascending aortic dilatation rate were also ***: Two hundred and eight patients were included,comprised of 86 BAV and 122 TAV patients. Five,4,3,2,and 1-year MDCT follow-ups were achieved in 7,9,30,46,and 116 patients. The ascending aortic diameter was significantly increased after TAVR in both BAV group(43.7±4.4 mm vs. 44.0±4.5 mm;Plinear regression revealed paravalvular leakage(PVL) grade was independently associated with ascending aortic dilatation rate in the whole population and BAV group,but not TAV group. No aortic events occurred during ***: Ascending aortic size continues to grow after TAVR in BAV patients,but the dilatation rate is mild and comparable to that of TAV patients. PVL grade is associated with ascending aortic dilatation rate in BAV patients post-TAVR.

关键词： Transcatheter aortic valve replacement Aortic dilatation Bicuspid aortic valve

A case of a successful post-transcatheter aortic valve replacement His bundle pacing

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World Journal of Emergency Medicine 2021年第2期12卷 157-159页

作者： Fei Lv Xiao-hong Pan Jia-qi Fan li-han wang Dan-dan Yang Xin-ping lin Hua-jun li Qi-feng Zhu Xian-baoliu Jian-an wang Department of Cardiology the Second Affi liated HospitalZhejiang University School of MedicineHangzhou 310009China

Dear editor,Transcatheter aortic valve replacement (TAVR) is a safe and effective treatment for severe aortic valve stenosis and aortic regurgitation. Multiple randomized trials have proved its therapeutic advantages ... 详细信息

关键词： aortic stenosis bundle

The first two cases of transcatheter mitral valve repair with ARTO system in Asia

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World Journal of Emergency Medicine 2020年第1期11卷 33-36页

作者： Kai-da Ren Zhao-xia Pu Lei Yu Feng Gao li-han wang Stella Ng Ju-bo Jiang Hua-jun li Yong Xu Wei He Min Yan Xian-bao liu Jian-an wang Cardiovascular Department the Second Affiliated Hospital Zhejiang University School of Medicine

BACKGROUND:MAVERIC(Mitral Valve Repair Clinical Trial)validates the safety and effi cacy of the ARTO *** here report the fi rst two successful cases of utilizing the ARTO system in patients with symptomatic heart failure(HF)with functional mitral regurgitation(FMR)in ***:Two patients,aged 70 and 63,had severe HF with *** echocardiography confirmed that the left ventricular ejection fractions were less than 50%with severe mitral regurgitation(MR)in both *** drug treatment could not mitigate their ***,we used the ARTO system to repair the mitral valve for these patients on March 5 and 6,2019,***:Mitral valve repairs using the ARTO system were successfully performed under general anaesthesia for these two *** was decreased immediately after the procedures in both *** 30-day and 3-month transthoracic echocardiography(TTE)revealed a moderate to severe MR in both patients,and the New York Heart Association(NYHA)scales were also partially ***:The first two cases in Asia indicate that the ARTO system is feasible for patients with heart failure with FMR,and the patient selection appears to be crucial.

关键词： Mitral regurgitation Mitral valve repair ARTO system

REACTION　MEChanISM　AND　DYNAMICS　OF　PASTE　BORONIZING　IN　A　PLASMA

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Chinese Journal of Mechanical Engineering 1997年第2期10卷 95-100,135页

作者： li Chunyang, han limin ,wang Jian, liu Ruixian, Tianjin University

The distribution of electric potential in plasma and paste is measured with samples equipped with probes under various technical conditions. A model of boronizing reaction is proposed based on the chemical reaction in the boronizing agent. A kinetic law of boronizing is deduced from the measured boronizing rate and the quality change under various temperature, time and discharging power conditions.

关键词： Glow discharging Plasma ,Boronizing with paste