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Mid-term outcomes of a kinematically designed cruciate retaining total knee arthroplasty
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作者 Jonathan L Katzman Akram A Habibi +4 位作者 Muhammad A Haider Casey Cardillo Ivan Fernandez-Madrid Morteza Meftah Ran Schwarzkopf 《World Journal of Orthopedics》 2024年第2期118-128,共11页
BACKGROUND Advances in implant material and design have allowed for improvements in total knee arthroplasty(TKA)outcomes.A cruciate retaining(CR)TKA provides the least constraint of TKA designs by preserving the nativ... BACKGROUND Advances in implant material and design have allowed for improvements in total knee arthroplasty(TKA)outcomes.A cruciate retaining(CR)TKA provides the least constraint of TKA designs by preserving the native posterior cruciate ligament.Limited research exists that has examined clinical outcomes or patient reported outcome measures(PROMs)of a large cohort of patients undergoing a CR TKA utilizing a kinematically designed implant.It was hypothesized that the studied CR Knee System would demonstrate favorable outcomes and a clinically significant improvement in pain and functional scores.AIM To assess both short-term and mid-term clinical outcomes and PROMs of a novel CR TKA design.METHODS A retrospective,multi-surgeon study identified 255 knees undergoing a TKA utilizing a kinematically designed CR Knee System(JOURNEY™II CR;Smith and Nephew,Inc.,Memphis,TN)at an urban,academic medical institution between March 2015 and July 2021 with a minimum of two-years of clinical follow-up with an orthopedic surgeon.Patient demographics,surgical information,clinical outcomes,and PROMs data were collected via query of electronic medical records.The PROMs collected in the present study included the Knee Injury and Osteoarthritis Outcome Score for Joint Replacement(KOOS JR)and Patient-Reported Outcomes Measurement Information System(PROMIS■)scores.The significance of improvements in mean PROM scores from preoperative scores to scores collected at six months and two-years postoperatively was analyzed using Independent Samples t-tests.RESULTS Of the 255 patients,65.5%were female,43.8%were White,and patients had an average age of 60.6 years.Primary osteoarthritis(96.9%)was the most common primary diagnosis.The mean surgical time was 105.3 minutes and mean length of stay was 2.1 d with most patients discharged home(92.5%).There were 18 emergency department(ED)visits within 90 d of surgery resulting in a 90 d ED visit rate of 7.1%,including a 2.4%orthopedic-related ED visit rate and a 4.7%non-orthopedic-related ED visit rate.There were three(1.2%)hospital readmissions within 90 d postoperatively.With a mean time to latest follow-up of 3.3 years,four patients(1.6%)required revision,two for arthrofibrosis,one for aseptic femoral loosening,and one for peri-prosthetic joint infection.There were significant improvements in KOOS JR,PROMIS Pain Intensity,PROMIS Pain Interference,PROMIS Mobility,and PROMIS Physical Health from preoperative scores to six month and two-year postoperative scores.CONCLUSION The evaluated implant is an effective,novel design offering excellent outcomes and low complication rates.At a mean follow up of 3.3 years,four patients required revisions,three aseptic and one septic,resulting in an overall implant survival rate of 98.4%and an aseptic survival rate of 98.8%.The results of our study demonstrate the utility of this kinematically designed implant in the setting of primary TKA. 展开更多
关键词 Total knee arthroplasty Cruciate retaining Kinematic design SURVIVORSHIP Bearing material Prosthetic design Clinical outcomes Patient-reported outcome measures
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Physical and Kinematical Characteristics of Wolf–Rayet Central Stars and their Host Planetary Nebulae
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作者 Z.Awad A.Ali 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第9期219-240,共22页
We address the physical and kinematical properties of Wolf–Rayet[WR]central stars(CSs)and their host planetary nebulae(PNe).The studied sample comprises all[WR]CSs that are currently known.The analysis is based on re... We address the physical and kinematical properties of Wolf–Rayet[WR]central stars(CSs)and their host planetary nebulae(PNe).The studied sample comprises all[WR]CSs that are currently known.The analysis is based on recent observations of the parallax,proper motion,and color index of[WR]CSs from the Gaia space mission’s early third release(eDR3)catalog,as well as common nebular characteristics.The results revealed an evolutionary sequence,in terms of decreasing Teff,from the early hot[WO 1]to the late cold[WC 12]stars.This evolutionary sequence extends beyond[WR]CS temperature and luminosity to additional CS and nebular characteristics.The statistical analysis shows that the mean final stellar mass and evolutionary age of the[WR]CS sample are 0.595±0.13M⊙and 9449±2437 yr,respectively,with a mean nebular dynamical age of 7270±1380 yr.In addition,we recognize that the color of the majority(∼85%)of[WR]CSs tends to be red rather than their genuine blue color.The analysis indicates that two-thirds of the apparent red color of most[WR]s is attributed to the interstellar extinction whereas the other one-third is due to the PN self-extinction effect. 展开更多
关键词 Wolf-Rayet-(ISM )planetary nebulae general-ISM kinematics and dynamics
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Kinematically Aligned Total Knee Arthroplasty for Valgus Osteoarthritis of More than 10°―Is It Still a “Challenging Surgery”?
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作者 Yoshinori Soda Toshiya Kano Mitsuhiro Nakamura 《Open Journal of Orthopedics》 2023年第9期355-369,共15页
Mechanically aligned total knee arthroplasty (TKA) for valgus knee is considered a “challenging surgery.” Recently, the kinematic alignment (KA) method has gained attention. This study aimed to present objective cli... Mechanically aligned total knee arthroplasty (TKA) for valgus knee is considered a “challenging surgery.” Recently, the kinematic alignment (KA) method has gained attention. This study aimed to present objective clinical data, such as intraoperative balance assessment and radiographic evaluation of postoperative lower extremity alignment after TKA using the KA method for valgus deformity. Twenty-one TKA knees (mean age, 74 years;2 males, 19 females) with KA for severe valgus deformity (hip-knee-ankle-angle ≥ 10°) performed at our department in the past 3 years were included in this study. Intraoperative gap and balance measurements and postoperative radiographic evaluation were performed. A total arc of range of motion was achieved up to 98% of preoperative values at 3 weeks postoperatively. Intraoperative gap and balance were stable throughout the entire range of motion. In addition, there were no statistically significant differences in either balance or gap values at each flexion angle. KA TKA is a “simple surgery” rather than a “challenging surgery” because additional soft tissue procedures are not required, operative time is short, intraoperative and postoperative balance is very stable, and a good alignment is achieved. This procedure may relieve surgeons of the stress of TKA for valgus deformities. 展开更多
关键词 Total Knee Arthroplasty Kinematic Alignment Valgus Deformity Calipered Technique
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Explicit Symplectic Geometric Algorithms for Quaternion Kinematical Differential Equation 被引量:1
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作者 Hong-Yan Zhang Zi-Hao Wang +3 位作者 Lu-Sha Zhou Qian-Nan Xue Long Ma Yi-Fan Niu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第2期479-488,共10页
Solving quaternion kinematical differential equations(QKDE) is one of the most significant problems in the automation, navigation, aerospace and aeronautics literatures. Most existing approaches for this problem neith... Solving quaternion kinematical differential equations(QKDE) is one of the most significant problems in the automation, navigation, aerospace and aeronautics literatures. Most existing approaches for this problem neither preserve the norm of quaternions nor avoid errors accumulated in the sense of long term time. We present explicit symplectic geometric algorithms to deal with the quaternion kinematical differential equation by modelling its time-invariant and time-varying versions with Hamiltonian systems and adopting a three-step strategy. Firstly,a generalized Euler's formula and Cayley-Euler formula are proved and used to construct symplectic single-step transition operators via the centered implicit Euler scheme for autonomous Hamiltonian system. Secondly, the symplecticity, orthogonality and invertibility of the symplectic transition operators are proved rigorously. Finally, the explicit symplectic geometric algorithm for the time-varying quaternion kinematical differential equation, i.e., a non-autonomous and non-linear Hamiltonian system essentially, is designed with the theorems proved. Our novel algorithms have simple structures, linear time complexity and constant space complexity of computation. The correctness and efficiencies of the proposed algorithms are verified and validated via numerical simulations. 展开更多
关键词 Linear time-varying system navigation system quaternion kinematical differential equation(QKDE) real-time computation symplectic method
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3D SLOPE STABILITY ANALYSIS WITH KINEMATICAL ELEMENT TECHNIQUE
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作者 Cao, Ping Gussmann, Peter 《中国有色金属学会会刊:英文版》 EI CSCD 1999年第2期218-222,共5页
1INTRODUCTIONTheanalyticalobjectofslopestabilityistodeterminethefactorofsafety(Fs)againstsliding,thelimiteq... 1INTRODUCTIONTheanalyticalobjectofslopestabilityistodeterminethefactorofsafety(Fs)againstsliding,thelimitequilibriumanalysis... 展开更多
关键词 kinematical ELEMENT methodstability analysisthree DIMENSIONAL SLOPE
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Analysis and Simulation of Kinematical Performances of Two Kinds of Parallel Mechanisms Based on the Plane Sprayer 被引量:1
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作者 DENG Jia-ming HE Hui-hui TANG Da-mei 《International Journal of Plant Engineering and Management》 2011年第4期237-242,共6页
Two kinds of 2-dof parallel mechanisms are proposed in this paper which can be used as the actuator for the plane sprayer. The direct and inverse kinematics solutions of the two kinds of mechanisms are derived on the ... Two kinds of 2-dof parallel mechanisms are proposed in this paper which can be used as the actuator for the plane sprayer. The direct and inverse kinematics solutions of the two kinds of mechanisms are derived on the end operating point and two workspaces are analyzed and compared. The kinematics models of the end operating point of two mechanisms are simulated by Matlab examples obtaining variation of kinematics parameters of these two mechanisms. The research of this paper provides the basis for the selection of mechanism, trajectory planning of the end operating point on the sprayer and often some practical value for trajectory analysis and structure design of the plane sprayer. 展开更多
关键词 SPRAYER parallel mechanism kinematics analysis kinematics simulation
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A Kinematical Calibration of the Galactocentric Distance
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作者 Ming Shen Zi Zhu 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2007年第1期120-128,共9页
We present a new determination of the Galactocentric distance by a pure kinematical model. Two subgroups of components from the Galactic thin disk, the O-B5 stars and the Galactic open clusters, were selected for our ... We present a new determination of the Galactocentric distance by a pure kinematical model. Two subgroups of components from the Galactic thin disk, the O-B5 stars and the Galactic open clusters, were selected for our analysis. On the basis of kinematical data of around 1200 O-B5 stars, we obtained an estimated value of Ro=8.25-4-0.79 kpc, while a similar evaluation from 270 Galactic open clusters gives Ro=7.95-4-0.62 kpc. Considering the scatter of Ro given by individual investigators with different methods, our present determinations agree well with the best value proposed by Reid. 展开更多
关键词 GALAXY kinematics and dynamics-stars early-type-open clusters and associations
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The kinematical and space structures of IC 2391 open cluster and moving group with Gaia-DR2
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作者 E.S.Postnikova W.H.Elsanhoury +3 位作者 Devesh P.Sariya N.V.Chupina S.V.Vereshchagin Ing-Guey Jiang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2020年第2期21-30,共10页
The kinematical parameters,spatial shape and structure of the open cluster IC 2391 and the associated stellar stream are studied here using Gaia Data Release 2(GDR2) astrometry data.The apex positions are determined f... The kinematical parameters,spatial shape and structure of the open cluster IC 2391 and the associated stellar stream are studied here using Gaia Data Release 2(GDR2) astrometry data.The apex positions are determined for the open cluster IC 2391(data taken from Cantat-Gaudin et al.) and for the kinematical stream’s stars mentioned in Montes et al.employing both convergent point and AD-diagram methods.The values of apex coordinates are:(A,D)CP=(6.~h17 ± 0.~h004,-6.°88 ± 0.°381;for cluster) and(6.~h07 ± 0.~h007,-5.°00 ± 0.°447;stream),and(A0,D0) =(6.~h12 ± 0.~h004,-3.°4 ± 0.°3;cluster) and(6.~h21 ±0.~h007,-11.°895 ± 0.°290;stream).The results are in good agreement with the previously calculated values.The positions of the stars in the disk and the spatial dispersion velocities are determined.The paths of cluster and associated stream are traced in the disk by orbit calculation back in time to their places of formation.A possible genetic relationship between the cluster and stream has been detected.The approximation of the spatial and kinematical shape of the stream and the cluster is made.According to this study,even though currently the cluster and stream seem to have a spatial difference in their locations,they appear to have formed in the same region of the Galactic disk. 展开更多
关键词 Stars:kinematics and dynamics Galaxy:stellar content (Galaxy:)open clusters and associations:individual:IC 2391
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Coronal Alignment of Three Different Types of Implants in Kinematically Aligned Total Knee Arthroplasty: A Comparative Study
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作者 Yoshinori Soda Mitsuhiro Nakamura Nobuo Adachi 《Open Journal of Orthopedics》 2021年第6期183-198,共16页
<b><span style="font-family:Verdana;">Background: </span></b><span style="font-family:Verdana;">The number of total knee arthroplasty (TKA) surgeries performed each ye... <b><span style="font-family:Verdana;">Background: </span></b><span style="font-family:Verdana;">The number of total knee arthroplasty (TKA) surgeries performed each year is increasing worldwide and mechanical alignment (MA) is currently seen as the gold standard procedure. However, taking neutral alignment as the universal goal may be mistaken. In our hospital, we currently conduct kinematically aligned TKA (KA-TKA). Three different types of implants are used</span><span style="font-family:Verdana;">:</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> the cruciate-retaining (CR) type, cruciate-sacrificing (CS) type, or bi-cruciate-retained (BCR) type. We aimed to compare the coronal alignment observed following KA-TKA and MA-TKA and in normal knees, as well as that achieved with different types of implants. </span><b><span style="font-family:Verdana;">Methods:</span></b><span style="font-family:Verdana;"> The study comprised 206 knees of Japanese patients who underwent KA-TKA using varying implants in our Hospital between May 2019 and April 2020. Measurements of pre- and postoperative coronal alignment were determined from weight-bearing full-leg standing radiographs. The postoperative results were </span><span style="font-family:Verdana;">compared to measurements taken from patients who underwent MA-TKA (</span><span style="font-family:Verdana;">N = 96) and normal knees (N = 60). </span><b><span style="font-family:Verdana;">Results: </span></b><span style="font-family:Verdana;">No significant differences between the KA-TKA group and normal knees were found for the medial proximal tibial angle (MPTA) (–4.2<span style="white-space:nowrap;">&deg;</span> </span></span><span style="font-family:;" "=""><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;"> 2.6<span style="white-space:nowrap;">&deg;</span> vs –3.8<span style="white-space:nowrap;">&deg;</span> </span><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;"> 2.5<span style="white-space:nowrap;">&deg;</span>) or joint line orientation angle (JLOA) (0.2<span style="white-space:nowrap;">&deg;</span> </span><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;"> 1.9<span style="white-space:nowrap;">&deg;</span> vs 0.3<span style="white-space:nowrap;">&deg;</span> </span><span style="font-family:Verdana;">±</span><span><span style="font-family:Verdana;"> 1.4<span style="white-space:nowrap;">&deg;</span>). However, when MA-TKA was compared to KA-TKA and normal knees, there were significant differences in both the MPTA and JLOA (</span><i><span style="font-family:Verdana;">p </span></i><span style="font-family:Verdana;">< 0.01). Furthermore, for the different implant types, MPTA exhibited significantly greater varus alignment when a CS-type was used than with the other two. </span><b><span style="font-family:Verdana;">Conclusions:</span></b><span style="font-family:Verdana;"> Here, we demonstrated that following KA-TKA, the articular surface of the tibia exhibited a similar varus alignment as that of normal knees, meaning that the technique reproduces the native knee. Furthermore, KA is patient-specific, and does not have the same failures as MA-TKA. Therefore, we anticipate a paradigm shift from mechanical to kinematic alignment, which may help reduce the dissatisfaction rate of TKA patients.</span></span></span> 展开更多
关键词 Total Knee Arthroplasty Kinematic Alignment Mechanical Alignment Calipered Technique
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A Kinematical Study of the NGC 7538 IRS 1 Region
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作者 Ye Xu +2 位作者 Xing-Wu Zheng 《Chinese Journal of Astronomy and Astrophysics》 CSCD 北大核心 2003年第2期133-141,共9页
We present high angular resolution images of both NH3 (1, 1) and (2, 2) lines toward NGC 7538 IRS 1. The density and velocity-position plots have been used to study the interaction among the outflows, winds and their ... We present high angular resolution images of both NH3 (1, 1) and (2, 2) lines toward NGC 7538 IRS 1. The density and velocity-position plots have been used to study the interaction among the outflows, winds and their environment. For the first time we have found an expanding half-shell of molecular gas around the HII region associated with IRS 1, which may be produced by the interaction of the bipolar outflows and the winds originating in IRS 1-3, and optical HII region NGC 7538 with ambient molecular gas. 展开更多
关键词 HII regions - ISM: clouds - ISM: individual (NGC 7538) - ISM:kinematics
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The ALMA-QUARKS Survey.Ⅰ.Survey Description and Data Reduction
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作者 刘训川 Tie Liu +31 位作者 Lei Zhu Guido Garay Hong-Li Liu Paul Goldsmith Neal Evans Kee-Tae Kim Sheng-Yuan Liu Fengwei Xu Xing Lu Anandmayee Tej Xiaofeng Mai Leonardo Bronfman Shanghuo Li Diego Mardones Amelia Stutz Ken'ichi Tatematsu Ke Wang Qizhou Zhang Sheng-Li Qin Jianwen Zhou Qiuyi Luo Siju Zhang Yu Cheng Jinhua He Qilao Gu Ziyang Li Zhenying Zhang Suinan Zhang Anindya Saha Lokesh Dewangan Patricio Sanhueza Zhiqiang Shen 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第2期104-124,共21页
This paper presents an overview of the QUARKS survey,which stands for Querying Underlying mechanisms of massive star formation with ALMA-Resolved gas Kinematics and Structures."The QUARKS survey is observing139 m... This paper presents an overview of the QUARKS survey,which stands for Querying Underlying mechanisms of massive star formation with ALMA-Resolved gas Kinematics and Structures."The QUARKS survey is observing139 massive clumps covered by 156 pointings at Atacama Large Millimeter/submillimeter Array(ALMA)Band 6(λ~1.3 mm).In conjunction with data obtained from the ALMA-ATOMS survey at Band 3(λ~3 mm),QUARKS aims to carry out an unbiased statistical investigation of massive star formation process within protoclusters down to a scale of 1000 au.This overview paper describes the observations and data reduction of the QUARKS survey,and gives a first look at an exemplar source,the mini-starburst Sgr B2(M).The wide-b and width(7.5 GHz)and high-angular-resolution(~0."3)observations of the QUARKS survey allow for the resolution of much more compact cores than those could be done by the ATOMS survey,and to detect previously unrevealed fainter filamentary structures.The spectral windows cover transitions of species including CO,SO,N_(2)D^(+),SiO,H_(30)α,H_(2)CO,CH_(3)CN,and many other complex organic molecules,tracing gas components with different temperatures and spatial extents.QUARKS aims to deepen our understanding of several scientific topics of massive star formation,such as the mass transport within protoclusters by(hub-)filamentary structures,the existence of massive starless cores,the physical and chemical properties of dense cores within protoclusters,and the feedback from already formed high-mass young protostars. 展开更多
关键词 STARS formation-stars kinematics and dynamics-ISM clouds-ISM MOLECULES
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Case Studies of the Microphysical and Kinematic Structure of Summer Mesoscale Precipitation Clouds over the Eastern Tibetan Plateau
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作者 Shuo JIA Jiefan YANG Hengchi LEI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第1期97-114,共18页
Three cases of microphysical characteristics and kinematic structures in the negative temperature region of summer mesoscale cloud systems over the eastern Tibetan Plateau(TP)were investigated using X-band dual-polari... Three cases of microphysical characteristics and kinematic structures in the negative temperature region of summer mesoscale cloud systems over the eastern Tibetan Plateau(TP)were investigated using X-band dual-polarization radar.The time-height series of radar physical variables and mesoscale horizontal divergence δderived by quasi-vertical profiles(QVPs)indicated that the dendritic growth layer(DGL,-20°C to-10°C)was ubiquitous,with large-value zones of K_(DP)(specific differential phase),Z_(DR)(differential reflectivity),or both,and corresponded to various dynamic fields(ascent or descent).Ascents in the DGL of cloud systems with vigorous vertical development were coincident with large-value zones of Z_(DR),signifying ice crystals with a large axis ratio,but with no obvious large values of K_(DP),which differs from previous findings.It is speculated that ascent in the DGL promoted ice crystals to undergo further growth before sinking.If there was descent in the DGL,a high echo top corresponded to large values of K_(DP),denoting a large number concentration of ice crystals;but with the echo top descending,small values of K_(DP) formed.This is similar to previous results and reveals that a high echo top is conducive to the generation of ice crystals.When ice particles fall to low levels(-10℃ to 0℃),they grow through riming,aggregation,or deposition,and may not be related to the kinematic structure.It is important to note that this study was only based on a limited number of cases and that further research is therefore needed. 展开更多
关键词 Tibetan Plateau polarimetric variables MICROPHYSICS dendritic growth layer kinematic structure aggregation RIMING
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浮动基多机协调吊运系统的工作空间分析
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作者 苏程 赵祥堂 +2 位作者 闫增祯 赵志刚 孟佳东 《哈尔滨工程大学学报(英文版)》 CSCD 2024年第1期148-159,共12页
At present,the cranes used at sea have several shortcomings in terms of flexibility,efficiency,and safety.Therefore,a floating multi-robot coordinated lifting system is proposed to fulfill the offshore lifting require... At present,the cranes used at sea have several shortcomings in terms of flexibility,efficiency,and safety.Therefore,a floating multi-robot coordinated lifting system is proposed to fulfill the offshore lifting requirements.First,the structure of the lifting system is established according to the lifting task,the kinematic model of the system is developed by using the D–H coordinate transformation,and the dynamic model is developed based on rigid-body dynamics and hydrodynamics.Then,the static and dynamic workspace of the lifting system are analyzed,and the solving steps of the workspace are given by using the Monte–Carlo method.The effect of the load mass and the maximum allowable tension of the cable on the workspace is examined by simulation.Results show that the lifting system has limited carrying capacity and a data reference for selecting the structural parameters by analyzing the factors affecting the workspace.Findings provide a basis for further research on the optimal design of structural parameters and the determination of safe configurations of the lifting system. 展开更多
关键词 Offshore lifting Multi-robot system Kinematic model Dynamic model Static workspace Dynamic workspace
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Kinematic deformation and intensity assessment of the 2021 Maduo M_(S)7.4 earthquake in Qinghai revealed by high-frequency GNSS
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作者 Yu Li Yuebing Wang +2 位作者 Lijiang Zhao Hongbo Shi Pingping Wang 《Geodesy and Geodynamics》 EI CSCD 2024年第3期230-240,共11页
Rapid acquisition of the kinematic deformation field and seismic intensity distribution of large earthquakes is crucial for postseismic emergency rescue,disaster assessment,and future seismic risk research.The advance... Rapid acquisition of the kinematic deformation field and seismic intensity distribution of large earthquakes is crucial for postseismic emergency rescue,disaster assessment,and future seismic risk research.The advancement of GNSS observation and data processing makes it play an important role in this field,especially the high-frequency GNSS.We used the differential positioning method to calculate the 1 HZ GNSS data from 98 sites within 1000 km of the M_(S)7.4 Maduo earthquake epicenter.The kinematic deformation field and the distribution of the seismic intensity by using the peak ground velocity derived from displacement waveforms were obtained.The results show that:1)Horizontal coseismic response deformation levels ranging from 25 mm to 301 mm can be observed within a 1000 km radius from the epicenter.Coseismic response deformation on the east and west sides shows bilateral asymmetry,which markedly differs from the symmetry presented by surface rupture.2)The seismic intensity obtained through high-frequency GNSS and field investigations exhibits good consistency of the scope and orientation in the high seismic intensity area,although the former is generally slightly smaller than the latter.3)There may exist obstacles on the eastern side of the seismogenic fault.The Maduo earthquake induced a certain tectonic stress loading effect on the western Kunlun Pass-Jiangcuo fault(KPJF)and Maqin-Maqu segment,resulting in higher seismic risk in the future. 展开更多
关键词 Maduo earthquake High-frequency GNSS Kinematic deformation Seismic intensity
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An approach for determination of lateral limit angle in kinematic planar sliding analysis for rock slopes
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作者 Xiaojuan Yang Jie Hu +1 位作者 Honglei Sun Jun Zheng 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1305-1314,共10页
Planar sliding is one of the frequently observed types of failure in rock slopes.Kinematic analysis is a classic and widely used method to examine the potential failure modes in rock masses.The accuracy of planar slid... Planar sliding is one of the frequently observed types of failure in rock slopes.Kinematic analysis is a classic and widely used method to examine the potential failure modes in rock masses.The accuracy of planar sliding kinematic analysis is significantly influenced by the value assigned to the lateral limit angleγlim.However,the assignment ofγlim is currently used generally based on an empirical criterion.This study aims to propose an approach for determining the value ofγlim in deterministic and probabilistic kinematic planar sliding analysis.A new perspective is presented to reveal thatγlim essentially influences the probability of forming a potential planar sliding block.The procedure to calculate this probability is introduced using the block theory method.It is found that the probability is correlated with the number of discontinuity sets presented in rock masses.Thus,different values ofγlim for rock masses with different sets of discontinuities are recommended in both probabilistic and deterministic planar sliding kinematic analyses;whereas a fixed value ofγlim is commonly assigned to different types of rock masses in traditional method.Finally,an engineering case was used to compare the proposed and traditional kinematic analysis methods.The error rates of the traditional method vary from 45%to 119%,while that of the proposed method ranges between 1%and 17%.Therefore,it is likely that the proposed method is superior to the traditional one. 展开更多
关键词 Kinematic analysis Block theory Planar sliding Lateral limit angle Rock slope
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Acute effect of foot strike patterns on in vivo tibiotalar and subtalar joint kinematics during barefoot running
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作者 Dongqiang Ye Lu Li +4 位作者 Shen Zhang Songlin Xiao Xiaole Sun Shaobai Wang Weijie Fu 《Journal of Sport and Health Science》 SCIE CSCD 2024年第1期108-117,共10页
Background:Foot kinematics,such as excessive eversion and malalignment of the hindfoot,are believed to be associated with running-related injuries.The maj ority of studies to date show that different foot strike patte... Background:Foot kinematics,such as excessive eversion and malalignment of the hindfoot,are believed to be associated with running-related injuries.The maj ority of studies to date show that different foot strike patterns influence these specific foot and ankle kinematics.However,technical deficiencies in traditional motion capture approaches limit knowledge of in vivo joint kinematics with respect to rearfoot and forefoot strike patterns(RFS and FFS,respectively).This study uses a high-speed dual fluoroscopic imaging system(DFIS)to determine the effects of different foot strike patterns on 3D in vivo tibiotalar and subtalar joints kinematics.Methods:Fifteen healthy male recreational runners underwent foot computed tomography scanning for the construction of 3-dimensional models.A high-speed DFIS(100 Hz)was used to collect 6 degrees of freedom kinematics for participants’tibiotalar and subtalar joints when they adopted RFS and FFS in barefoot condition.Results:Compared with RFS,FFS exhibited greater internal rotation at 0%-20%of the stance phase in the tibiotalar joint.The peak internal rotation angle of the tibiotalar joint under FFS was greater than under RFS(p<0.001,Cohen’s d=0.92).RFS showed more dorsiflexion at 0%-20%of the stance phase in the tibiotalar joint than FFS.RFS also presented a larger anterior translation(p<0.001,Cohen’s d=1.28)in the subtalar joint at i nitial contact than FFS.Conclusion:Running with acute barefoot FFS increases the internal rotation of the tibiotalar joint in the early stance.The use of high-speed DFIS to quantify the movement of the tibiotalar and subtalar joint was critical to revealing the effects of RF S and FFS during running. 展开更多
关键词 Foot strike patterns High-speed dual fluoroscopic imaging system In vivo kinematics Running
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Evaluation of slope stability through rock mass classification and kinematic analysis of some major slopes along NH-1A from Ramban to Banihal, North Western Himalayas
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作者 Amit Jaiswal A.K.Verma T.N.Singh 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期167-182,共16页
The network of Himalayan roadways and highways connects some remote regions of valleys or hill slopes,which is vital for India’s socio-economic growth.Due to natural and artificial factors,frequency of slope instabil... The network of Himalayan roadways and highways connects some remote regions of valleys or hill slopes,which is vital for India’s socio-economic growth.Due to natural and artificial factors,frequency of slope instabilities along the networks has been increasing over last few decades.Assessment of stability of natural and artificial slopes due to construction of these connecting road networks is significant in safely executing these roads throughout the year.Several rock mass classification methods are generally used to assess the strength and deformability of rock mass.This study assesses slope stability along the NH-1A of Ramban district of North Western Himalayas.Various structurally and non-structurally controlled rock mass classification systems have been applied to assess the stability conditions of 14 slopes.For evaluating the stability of these slopes,kinematic analysis was performed along with geological strength index(GSI),rock mass rating(RMR),continuous slope mass rating(CoSMR),slope mass rating(SMR),and Q-slope in the present study.The SMR gives three slopes as completely unstable while CoSMR suggests four slopes as completely unstable.The stability of all slopes was also analyzed using a design chart under dynamic and static conditions by slope stability rating(SSR)for the factor of safety(FoS)of 1.2 and 1 respectively.Q-slope with probability of failure(PoF)1%gives two slopes as stable slopes.Stable slope angle has been determined based on the Q-slope safe angle equation and SSR design chart based on the FoS.The value ranges given by different empirical classifications were RMR(37-74),GSI(27.3-58.5),SMR(11-59),and CoSMR(3.39-74.56).Good relationship was found among RMR&SSR and RMR&GSI with correlation coefficient(R 2)value of 0.815 and 0.6866,respectively.Lastly,a comparative stability of all these slopes based on the above classification has been performed to identify the most critical slope along this road. 展开更多
关键词 Rock mass classification Kinematic analysis Slope stability Himalayan road Static and dynamic conditions
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A Fermi-LAT Study of Globular Cluster Dynamical Evolution in the Milky Way:Millisecond Pulsars as the Probe
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作者 Li Feng Zhongqun Cheng +2 位作者 Wei Wang Zhiyuan Li Yang Chen 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第2期1-23,共23页
Using archival Fermi-LAT data with a time span of~12 yr,we study the population of Millisecond Pulsars(MSPs)in Globular Clusters(GlCs)and investigate their dependence on cluster dynamical evolution in the Milky Way.We... Using archival Fermi-LAT data with a time span of~12 yr,we study the population of Millisecond Pulsars(MSPs)in Globular Clusters(GlCs)and investigate their dependence on cluster dynamical evolution in the Milky Way.We show that theγ-ray luminosity(L_(γ))and emissivity(i.e.,ε_(γ)=L_(γ)/M,with M the cluster mass)are good indicators of the population and abundance of MSPs in GlCs,and they are highly dependent on the dynamical evolution history of the host clusters.Specifically speaking,the dynamically older GlCs with more compact structures are more likely to have larger L_(γ)andε_(γ),and these trends can be summarized as strong correlations with cluster stellar encounter rateΓand the specific encounter rate(Λ=Γ/M),with L_(γ)∝Γ^(0.7±0.11)andε_(γ)∝Λ^(0.73±0.13)for dynamically normal GlCs.However,as GlCs evolve into deep core collapse,these trends are found to be reversed,implying that strong encounters may have lead to the disruption of Low-Mass X-ray Binaries and ejection of MSPs from core-collapsed systems.Besides,the GlCs are found to exhibit largerε_(γ)with increasing stellar mass function slope(ε_(γ)∝10^((0.52±0.1)α)),decreasing tidal radius(ε_(γ)∝R_(t)^(-10±0.22))and distances from the Galactic Center(GC,ε_(γ)∝R_(gc)^(-1.13±0.21)).These correlations indicate that,as GlCs losing kinetic energy and spiral in toward the GC,tidal stripping and mass segregation have a preference in leading to the loss of normal stars from GlCs,while MSPs are more likely to concentrate to cluster center and be deposited into the GC.Moreover,we gaugeε_(γ)of GlCs is~10-1000 times larger than the Galactic bulge,the latter is thought to reside thousands of unresolved MSPs and may be responsible for the GC 7-ray excess,which supports that GlCs are generous contributors to the population of MSPs in the GC. 展开更多
关键词 (Galaxy:)globular clusters general-(stars:)pulsars general-Galaxy kinematics and dynamics-Galaxy center-Galaxy bulge-gamma-rays stars-gamma-rays diffuse background-gamma-rays galaxies
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Deformation characteristics of granitic rocks in Erguna ductile shear zone,NE China
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作者 NWABUEZE Ekene Chibuike LIANG Chenyue +3 位作者 SONG Zhiwei ZHAO jiaqi ENEZE Florence Ego ZHENG Changqing 《Global Geology》 2024年第2期63-75,共13页
The Erguna ductile shear zone is situated in the Erguna Massif,which has been exposed along the eastern bank of the Erguna River in northeastern China.The authors present comprehensive study results on the macro-and m... The Erguna ductile shear zone is situated in the Erguna Massif,which has been exposed along the eastern bank of the Erguna River in northeastern China.The authors present comprehensive study results on the macro-and micro-structures,finite strain and kinematic vorticity,quartz electron backscatter diffraction(EBSD)fabrics,and geochronology of granitic rocks in the Erguna ductile shear zone.The deformed granitic rocks have experienced significant SE-trending dextral strike-slip shearing.Finite strain and kinematic vorticity in all deformed granitic rocks indicate that the deformation is characterized by simple sheardominated general shearing with S-L tectonites.Mineral deformation behaviors and quartz C-axis textures demonstrate that the deformed granitic rocks developed under greenschist to amphibolite facies conditions at deformation temperatures ranging from 450 to 550℃.New LA-ICP-MS zircon U-Pb ages indicate that these granitic rocks were formed in Early Triassic(~248.6 Ma)and Early Cretaceous(~136.7 Ma).All the evidence indicates that this deformation may have occurred in Early Cretaceous and was related to the compression resulting from the final closure of the Mongol-Okhotsk Ocean. 展开更多
关键词 zircon U-Pb dating EBSD analysis finite strain kinematic vorticity Erguna ductile shear zone
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3-Dimensional Kinematic Comparison of Arm Movements between an Individual with NGLY1 Deficiency and a Neurotypical Individual
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作者 Charles S. Layne Christopher A. Malaya +6 位作者 Brock Futrell Dacia Martinez Diaz Christian Alfaro Hannah E. Gustafson Subhalakshmi Chandrasekaran Rhea M. Phatak Bernhard Suter 《Case Reports in Clinical Medicine》 2024年第4期122-146,共25页
NGLY1 Deficiency is an ultra-rare autosomal recessively inherited disorder. Characteristic symptoms include among others, developmental delays, movement disorders, liver function abnormalities, seizures, and problems ... NGLY1 Deficiency is an ultra-rare autosomal recessively inherited disorder. Characteristic symptoms include among others, developmental delays, movement disorders, liver function abnormalities, seizures, and problems with tear formation. Movements are hyperkinetic and may include dysmetric, choreo-athetoid, myoclonic and dystonic movement elements. To date, there have been no quantitative reports describing arm movements of individuals with NGLY1 Deficiency. This report provides quantitative information about a series of arm movements performed by an individual with NGLY1 Deficiency and an aged-matched neurotypical participant. Three categories of arm movements were tested: 1) open ended reaches without specific end point targets;2) goal-directed reaches that included grasping an object;3) picking up small objects from a table placed in front of the participants. Arm movement kinematics were obtained with a camera-based motion analysis system and “initiation” and “maintenance” phases were identified for each movement. The combination of the two phases was labeled as a “complete” movement. Three-dimensional analysis techniques were used to quantify the movements and included hand trajectory pathlength, joint motion area, as well as hand trajectory and joint jerk cost. These techniques were required to fully characterize the movements because the NGLY1 individual was unable to perform movements only in the primary plane of progression instead producing motion across all three planes of movement. The individual with NGLY1 Deficiency was unable to pick up objects from a table or effectively complete movements requiring crossing the midline. The successfully completed movements were analyzed using the above techniques and the results of the two participants were compared statistically. Almost all comparisons revealed significant differences between the two participants, with a notable exception of the 3D initiation area as a percentage of the complete movement. The statistical tests of these measures revealed no significant differences between the two participants, possibly suggesting a common underlying motor control strategy. The 3D techniques used in this report effectively characterized arm movements of an individual with NGLY1 deficiency and can be used to provide information to evaluate the effectiveness of genetic, pharmacological, or physical rehabilitation therapies. 展开更多
关键词 NGLY1 Deficiency Developmental Disorders KINEMATICS 3 Dimensional Analyses
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