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Modeling joints with clearance and friction in multibody dynamic simulation of automotive differentials

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Theoretical & Applied Mechanics Letters 2013年第1期3卷 32-38页

作者： Geoffrey Virlez Olivier brüls Emmanuel Tromme Pierre Duysinx Department of Aerospace and Mechanical Engineering (LTAS) University of Liège

Defects in kinematic joints can sometimes highly influence the simulation response of the whole multibody system within which these joints are included. For instance, the clearance, the friction, the lubrication and the flexibility affect the transient behaviour, reduce the component life and produce noise and vibration for classical joints such as prismatics, cylindrics or universal *** this work, a new 3D cylindrical joint model which accounts for the clearance, the misalignment and the friction is presented. This formulation has been used to represent the link between the planet gears and the planet carrier in an automotive differential model. C 2013 The Chinese Society of Theoretical and Applied Mechanics. [doi：10.1063/2.1301303]

关键词： cylindrical joint clearance friction automotive differential, multibody dynamics

白内障摘除联合玻璃体切除术中5种新型人工晶状体计算公式准确性的前瞻性比较

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眼科 2024年第4期33卷 295-300页

作者：何渊朱静芬赵世强宋旭东刘武首都医科大学附属北京同仁医院、北京同仁眼科中心眼科学与视觉科学北京市重点实验室北京100730 上海交通大学医学院上海200025

目的比较在白内障联合玻璃体切除(pars plana vitrectomy,PPV)手术中,五种新型人工晶状体(intraocular lens,IOL)计算公式(BUⅡ、EVO 2.0、Kane、LSF、以及RBF 3.0)的预测准确性。设计前瞻性非随机对照研究。研究对象2021年9月至2022年1... 详细信息

目的比较在白内障联合玻璃体切除(pars plana vitrectomy,PPV)手术中,五种新型人工晶状体(intraocular lens,IOL)计算公式(BUⅡ、EVO 2.0、Kane、LSF、以及RBF 3.0)的预测准确性。设计前瞻性非随机对照研究。研究对象2021年9月至2022年11月期间因单纯白内障接受白内障摘除联合IOL植入的患者52例(52眼)(对照组),以及因白内障合并全层黄斑裂孔或黄斑前膜行白内障摘除、IOL植入联合PPV术的患者52例(52眼)(研究组)。方法使用BUⅡ公式进行两组患者IOL屈光度计算,检查并记录所有患者术前和术后1个月最佳矫正视力,计算五种IOL计算公式的屈光误差(predictive error,PE)、PE的标准差、平均绝对误差、绝对误差中位数和PE在±0.25 D、±0.50 D、±0.75 D和±1.00 D范围内的眼数百分比。并使用Cooke法进行公式预测性的比较。主要指标应用五种IOL计算公式后的PE。结果对照组中,Kane和EVO 2.0公式的PE分别为(0.20±0.39)D及(0.19±0.40)D,呈现远视系统误差(分别为t=3.41,P=0.001,及t=3.60,P=0.001),BUⅡ、LSF、及RBF 3.0公式无系统误差。在研究组中,五种公式同0比较均无显著性差异。所有公式在研究组中的标准差、平均绝对误差、绝对误差中位数和PE在±0.25 D、±0.50 D、±0.75 D和±1.00 D范围内的眼数百分比均逊于对照组。经过公式预测性比较,对照组中,Kane公式及LSF公式排名最高(均为2.33),而研究组中,BUⅡ公式表现最佳(1.83)。结论术后1个月时,在研究组中应用BU Ⅱ、LSF、Kane、EVO 2.0及RBF 3.0公式均未显示出远视或近视漂移,但其公式预测准确性较对照组差,表现为较大的标准差、平均绝对误差及绝对误差中位数,及在所有给定范围内PE的比例均低于对照组。但其中预测准确性表现最优者为BU Ⅱ公式。

关键词：白内障玻璃体切除术人工晶状体计算公式

Changing trends in penetrating keratoplasty indications at a tertiary eye care center in Budapest,Hungary between 2006 and 2017

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International Journal of Ophthalmology(English edition) 2020年第11期13卷 1814-1819页

作者： Milan Tamas Pluzsik Gabor Toth Jeannette Toth Andrds Matolcsy achim Langenbucher Agnes Kerenyi Zoltdn Zsolt Nagy Nora Szentmary Department of Ophthalmology Semmelweis UniversityBudapest 1085Hungary Department of Ophthalmology Bajcsy-Zsilinszky HospitalBudapest 1106.Hungary 2^(nd)Department of Pathology Semmelweis UniversityBudapest 1091Hungary 1^(st)Department of Pathology and Experimental Cancer Research Semmelweis UniversityBudapest 1085Hungary Experimental Ophthalmology Saarland UniversityHomburg/Saar 66421Germany Dr.Rolf M.Schwiete Center for Limbal Stem Cell and Congenital Aniridia Research Saarland University Homburg/Saar 66424Germany

AIM:To analyze the changing trends in penetrating keratoplasty(PKP)***:This retrospective study included all patients with PKP between 2006 and *** were classified using histological *** groups were as the following:pseudophakic or aphakic bullous keratopathy,regraft,acute necrotizing and ulcerative keratitis,keratoconus,Fuchs'dystrophy,corneal dystrophy other than Fuchs',corneal scar,other diagnoses and failed endothelial keratoplasty ***,two different time-periods(2006-2012 and 2013-2017)were ***:Totally 1721 histological analyses of 1214 patients were available for *** diagnoses were pseudophakic or aphakic bullous keratopathy in 487(28.3%),regraft in 443(25.7%),acute necrotizing and ulcerative keratitis in 313(18.2%),corneal scar in 153(8.9%),keratoconus in 140(8.1%).Fuchs'dystrophy in 61(3.5%),corneal dystrophy other than Fuchs'in 46(2.7%),other diagnoses in 44(2.6%)and failed endothelial keratoplasty graft in 34(2.0%)*** the first to the second analysed time-period,incidence of acute necrotizing and ulcerative keratitis,corneal scar,Fuchs'dystrophy increased(P<0.032 for all)and incidence of keratoconus significantly decreased(P=0.015).CONCLUSION:Pseudophakic or aphakic bullous keratopathy is the leading indication for PKP,followed by regraft and acute necrotizing and ulcerative keratitis.

关键词： penetrating keratoplasty indications histology

broadband quasi-phase-matching in dispersion-engineered all-optically poled silicon nitride waveguides

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Photonics Research 2020年第9期8卷 1475-1483页

作者： EDGARS NITISS BORIS ZABELICH OZAN YAKAR JUNQIU LIU RUI NING WANG TOBIAS J.KIPPENBERG AND CAMILLE-SOPHIE brÈS Ecole Polytechnique Fédérale de Lausanne(EPFL) Photonic Systems Laboratory(PHOSL)STI-IELStation 11CH-1015 LausanneSwitzerland Ecole Polytechnique Fédérale de Lausanne(EPFL) Laboratory of Photonics and Quantum Measurements(LPQM)SB-IPHYSStation 3CH-1015 LausanneSwitzerland

Quasi-phase-matching(QPM)has become one of the most common approaches for increasing the efficiency of nonlinear three-wave mixing processes in integrated photonic ***,we provide a study of dispersion engineering of QPM second-harmonic(SH)generation in stoichiometric silicon nitride(Si3 N4)*** apply waveguide design and lithographic control in combination with the all-optical poling technique to study the QPM properties and shape the waveguide dispersion for broadband spectral conversion efficiency inside Si3 N4 *** meeting the requirements for maximal bandwidth of the conversion efficiency spectrum,we demonstrate that group-velocity matching of the pump and SH is simultaneously satisfied,resulting in efficient SH generation from ultrashort optical *** latter is employed for retrieving a carrier-envelope-offset frequency of a frequency comb by using an f-2 f interferometric technique,where supercontinuum and SH of a femtosecond pulse are generated in Si3N4 ***,we show that the waveguide dispersion determines the QPM wavelength variation magnitude and sign due to the thermo-optic effect.

关键词： waveguide waveguides pump

The Leaf Reticulate Mutant dovl Is Impaired in the First Step of Purine Metabolism

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Molecular Plant 2012年第6期5卷 1227-1241页

作者： Christian Rosar Kerstin Kanonenberg Arun M. Nanda Michael Mielewczik Andrea brautigam Ondrej Novake Miroslav Strnad achim Walter Andreas RM. Weber Institute for Plant Biochemistry Heinrich-Heine-Universitat Universitatsstrasse 1 D-40225 Dusseldorf Germany Present address: Institute of Bio- and Geosciences IBG-1: Biotechnology Forschungszentrum Julich D-52425 Julich Germany Institute of Bio- and Geosciences IBG-2: Plant Sciences Forschungszentrum Julich D-52425 Julich Germany Present address: Institute of Agricultural Sciences Universitatstrasse 2 ETH Zurich CH-8092 Zurich Switzerland Laboratory of Growth Regulators Palacky University & Institute of Experimental Botany AS CR Slechtitelu 11 CZ-78371 Olomouc Czech Republic

A series of reticulated Arabidopsis thaliana mutants were previously described. All mutants show a reticulate leaf pattern, namely green veins on a pale leaf lamina. They have an aberrant mesophyll structure but an intact layer of bundle sheath cells around the veins. Here, we unravel the function of the previously described reticulated EMS-mutant dovl （differential development of vascular associated cells 1）. By positional cloning, we identified the mutated gene, which encodes glutamine phosphoribosyl pyrophosphate aminotransferase 2 （ATase2）, an enzyme catalyzing the first step of purine nucleotide biosynthesis, dovl is allelic to the previously characterized cial-2 mutant that was isolated in a screen for mutants with impaired chloroplast protein import. We show that purine-derived total cytokinins are lowered in clovl and crosses with phytohormone reporter lines revealed differential reporter activity patterns in dovl. Metabolite profiling unraveled that amino acids that are involved in purine biosynthesis are increased in dovl. This study identified the mo- lecular basis of an established mutant line, which has the potential for further investigation of the interaction between metabolism and leaf development.

关键词： leaf development reticulated mutants cytokinin growth kinetics purine metabolism.

Acute effects of partial-body vibration in sitting position

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World Journal of Orthopedics 2018年第9期9卷 156-164页

作者： Yannik Faes Nora Banz Nathalie Buscher Angela Blasimann Lorenz Radlinger Patric Eichelberger achim Elfering Department of Work and Organizational Psychology University of Bern Department of Health Professions Bern University of Applied Sciences

AIM To investigate the acute effects of sinusoidal and stochastic resonance partial-body vibration in sitting position, including muscle activity, heart rate variability, balance and *** Fifty healthy participants were assigned randomly to two training conditions: A sinusoidal partial-body vibration(SIN, 8 Hz) or a stochastic resonance partial-body vibration(STOCH, 8 ± 2 Hz). For baseline assessment participants sat on the vibration platform without vibration. Both training conditions consisted of five series of a one-minute vibration training and a one-minutebreak between them. In this experimental study surface electromyography(EMG) of the erector spinae(ES), one of the back muscles, and heart rate variability(HRV) was measured at baseline and during training. Balance and flexibility were assessed at baseline and immediately after training. Balance was measured with the modified star excursion balance test(mS EBT) and flexibility was assessed through the modified fingertip-to-floor method(mF TF).RESULTS Paired sample t-test showed a significant increase in balance that was restricted to STOCH(t =-2.22, P = 0.018; SIN: t =-0.09, P = 0.466). An increase in flexibility was also restricted to STOCH(t = 2.65, P = 0.007; SIN: t = 1.41, P = 0.086). There was no significant change of muscle activity in the ES-EMG in STOCH or SIN conditions. In both training conditions, HRV decreased significantly, but remained in a low-load range(STOCH: t = 2.89, P = 0.004; SIN: t = 2.55, P = 0.009).CONCLUSION In sitting position, stochastic resonance partial-body vibration can improve balance and flexibility while cardiovascular load is low. STOCH can be a valuable training option to people who are unable to stand(e.g., people, who are temporarily wheelchair-bound).

关键词： Partial-body vibration Balance Flexibility Sinusoidal Stochastic resonance

Delivery of genetic load during ex situ liver machine perfusion with potential for CRISPR-Cas9 gene editing:An innovative strategy for graft treatment

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Hepatobiliary & Pancreatic Diseases International 2021年第5期20卷 503-505页

作者： Eliano Bonaccorsi-Riani Andrew Gillooly Isabel M.A.brüggenwirth Paulo N.Martins Abdominal Transplant Unit Cliniques Universitaires Saint LucUniversitéCatholique de LouvainBrusselsBelgium Pole de Chirurgie Expérimentale et Transplantation UniversitéCatholique de LouvainBrusselsBelgium Department of Surgery Transplant DivisionUniversity of MassachusettsWorcester-MassachusettsUSA Department of Surgery Section of hepatobiliary surgery and liver transplantationUniversity Medical Center GroningenUniversity of GroningenGroningenThe Netherlands

To the Editor:Over the years,the shortage of suitable donor organs has challenged the transplant community in performing life-saving liver transplantation(LT).Recent reports from European and American liver transplant... 详细信息

关键词： organs mortality graft

基于纤维取向分布的应变硬化超高性能混凝土薄层抗拉性能

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硅酸盐学报 2021年第11期49卷 2384-2392页

作者：沈秀将邵旭东 brüHWILER Eugen 湖南大学土木工程学院中国长沙410082 瑞士洛桑联邦理工大学(EPFL) 瑞士CH-1015

采用电磁无损检测分析自由流动浇筑的应变硬化超高性能混凝土(SH-UHPC)薄板内纤维取向分布,对沿垂直流动方向切割的试件进行直接拉伸试验(DTT)、四点弯曲试验(4PBT)及反分析。结果表明:在水平自由流动状态下,SH-UHPC薄层中纤维趋于垂直... 详细信息

采用电磁无损检测分析自由流动浇筑的应变硬化超高性能混凝土(SH-UHPC)薄板内纤维取向分布,对沿垂直流动方向切割的试件进行直接拉伸试验(DTT)、四点弯曲试验(4PBT)及反分析。结果表明:在水平自由流动状态下,SH-UHPC薄层中纤维趋于垂直流动方向分布;SH-UHPC薄板内抗拉性能(非弹性段)波动大,主要由于纤维取向随着流动距离而不断变化;相比于4PBT,DTT能够更直接、更全面且更准确的得到SH-UHPC的抗拉性能。此外,基于试验及统计数据分析表明,SH-UHPC薄板中(90°方向)抗拉强度修正系数K_(f)=1.12,低于法国AFGC的推荐值;极限应变修正系数K_(ε)=1.25。

关键词：应变硬化超高性能混凝土无损检测直接拉伸试验四点弯曲试验纤维取向

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基于会话的安全、鲁棒共享控制方法(英文)

软件学报 2004年第12期15卷 1764-1775页

作者： Bernd Krieg-brckner Robert J Ross BISS BremenInstituteforSafeSystemsGermanyBISSBremenInstituteforSafeSystemsGermany

在共享控制系统中,比如智能服务机器人,操作员和自动化专门系统相互配合,共同控制.有效的共享控制需要复杂的系统体系结构,该结构可以提供安全鲁棒的运行,提供对用户友好的界面.满足这两项需求是一个不寻常的任务.介绍了解决这些问题的... 详细信息

在共享控制系统中,比如智能服务机器人,操作员和自动化专门系统相互配合,共同控制.有效的共享控制需要复杂的系统体系结构,该结构可以提供安全鲁棒的运行,提供对用户友好的界面.满足这两项需求是一个不寻常的任务.介绍了解决这些问题的方法.首先给出一个以会话为中心采用面向代理编程和形式化方法的认知控制体系结构.采用混成设计的SharC认知控制体系结构,可以区分协同代理群体中每一个遥控设备的控制.安全性对共享控制系统来说是极为重要的,因此这种体系结构必须能够保证较高的安全性.最后,描述了作为控制系统核心的形式化建模会话管理器,通过示范平台中自动轮椅的例子说明这些不同的软件范例的应用.

关键词：共享控制认知控制体系结构面向代理编程形式化方法混成设计