目的:研究全膝关节置换术结合康复功能训练对单侧膝内翻合并屈曲畸形患者的修复效果。方法:选取笔者医院于2017年10月-2018年10月收治的60例单侧膝内翻合并屈曲畸形患者进行研究,按照随机数字表法,随机分为实验组和对照组,每组30例。对...目的:研究全膝关节置换术结合康复功能训练对单侧膝内翻合并屈曲畸形患者的修复效果。方法:选取笔者医院于2017年10月-2018年10月收治的60例单侧膝内翻合并屈曲畸形患者进行研究,按照随机数字表法,随机分为实验组和对照组,每组30例。对照组应用常规手术治疗及护理,实验组则应用全膝关节置换术结合康复功能训练。观察并比较两组患者临床治疗效果、美国特种外科医院膝关节评分(Hospital for special surgery knee score,HSS)情况、膝关节功能恢复情况、患者满意度以及并发症发生情况。结果:治疗后,实验组优良率达到83.33%高于对照组的60.00%,差异有统计学意义(P<0.05)。术后1个月、3个月、6个月,两组患者膝关节HSS评分较出院时均明显升高,且实验组升高水平较对照组更为明显(P<0.05)。两组患者屈曲挛缩度、膝关节股胫角以及膝关节屈伸活动度均较治疗前有明显改善,且实验组较对照组改善更为显著(P<0.05)。实验组患者总满意度达90.00%高于对照组的63.33%,差异有统计学意义(P<0.05)。两组患者均发生腓总神经麻痹、深部感染等并发症,实验组并发症发生率为6.67%显著低于对照组的26.67%,差异有统计学意义(P<0.05)。结论:全膝关节置换术结合康复功能训练治疗单侧膝内翻合并屈曲畸形临床疗效和修复效果均显著,患者术后膝关节HSS评分、屈曲挛缩度、膝关节股胫角、膝关节屈伸活动度均显著改善,可有效提高患者满意度且并发症较少,值得在临床推广。展开更多
The process to achieve time synchronization and ranging for a network of mobile nodes is raising a concern among researchers, and hence a variety of joint time synchronization and ranging algorithms have been proposed...The process to achieve time synchronization and ranging for a network of mobile nodes is raising a concern among researchers, and hence a variety of joint time synchronization and ranging algorithms have been proposed in recent years. However, few of them handle the case of all-node motion under unknown positions and velocities. This study addresses the problem of determining ranging and time synchronization for a group of nodes moving within a local area. First, we examined several models of clock discrepancy and synchronous two-way ranging. Based upon these models, we present a solution for time synchronization with known positions and velocities. Next, we propose a functional model that jointly estimates the clock skew, clock offset, and time of flight in the absence of a priori knowledge for a pair of mobile nodes. Then, we extend this model to a network-wide time synchronization scheme by way of a global least square estimator. We also discuss the advantages and disadvantages of our model compared to the existing algorithms, and we provide some applicable scenarios as well. Finally, we show that the simulation results verify the validity of our analysis.展开更多
An improved measurement algorithm, based upon the theory of two-way time transfer （ TWTT）, is proposed to measure satellites with high speeds. The algorithm makes theoretical analyses and corresponding deductions on...An improved measurement algorithm, based upon the theory of two-way time transfer （ TWTT）, is proposed to measure satellites with high speeds. The algorithm makes theoretical analyses and corresponding deductions on a relative motion model of two satellites, and eliminates the measurement error caused by the equipment delay when a satellite moves at a high speed. Theoretical analysis and simulation results demonstrate that in comparison with the conventional TWTT algorithm, the proposed algorithm can significantly enhance the measurement accuracy of the inter-satellite ranging and time synchronization, and the algorithm is more effective with the relative velocity between the satellites and transmitting delay becoming larger.展开更多
由STM32和DW1000构成UWB(UltraWideBand)传感器,应用三UWB基站对UWB移动站实现定位,基于UWB测距值建立定位模型。使用基于ToF(Time of Flight)的单边双向测距算法及双边双向测距算法设计测距实验,得到室内测距误差10cm〜30cm,使用基于最...由STM32和DW1000构成UWB(UltraWideBand)传感器,应用三UWB基站对UWB移动站实现定位,基于UWB测距值建立定位模型。使用基于ToF(Time of Flight)的单边双向测距算法及双边双向测距算法设计测距实验,得到室内测距误差10cm〜30cm,使用基于最小二乘的线性拟合算法校正误差,校正后测距误差在10cm内。经比较,选择单边双向测距算法参与定位。分析了三边定位法、三角形质心定位法、最小二乘定位法、Fang定位法,选择后两种算法进行室内定位实验,并随机取定位样本点分析定位值分布。在普通客厅环境中,两种算法x,y方向的定位误差均在15cm内,最小二乘法定位值分布更均匀。展开更多
This paper studies the key techniques of the measurement and communication system for inter-satellite links(ISLs) of global navigation satellite system.A fixed link topology is designed based on the analysis of inter-...This paper studies the key techniques of the measurement and communication system for inter-satellite links(ISLs) of global navigation satellite system.A fixed link topology is designed based on the analysis of inter-satellite geometric properties and spatial parameters of the standard Walker24/3/2 constellation.This design can achieve full network coverage with small num-ber of hops,significantly reduce the number of ISLs,and enhance the feasibility and reliability of the system.A new time-division duplex mode,as well as an integrated measurement and communication scheme,is proposed based on the de-signed topology.Furthermore,mathematical formulas,error models,and modification methods regarding two-way ranging and time synchronization algorithms using spread spectrum non-coherent data frame for this new system are comprehensively dis-cussed.Theoretical analysis and simulation studies demonstrate that our design,compared with current GPS systems,has higher ranging and time synchronization precision,improved measurement efficiency,and higher channel utilization ratio and data transmission rate.It has no restrictions of constellation configuration,making it suitable for both MEO and the future MEO/GEO hybrid constellations.The results in this paper can serve as strong technical support for the next generation of GNSS ISL.展开更多
文摘目的:研究全膝关节置换术结合康复功能训练对单侧膝内翻合并屈曲畸形患者的修复效果。方法:选取笔者医院于2017年10月-2018年10月收治的60例单侧膝内翻合并屈曲畸形患者进行研究,按照随机数字表法,随机分为实验组和对照组,每组30例。对照组应用常规手术治疗及护理,实验组则应用全膝关节置换术结合康复功能训练。观察并比较两组患者临床治疗效果、美国特种外科医院膝关节评分(Hospital for special surgery knee score,HSS)情况、膝关节功能恢复情况、患者满意度以及并发症发生情况。结果:治疗后,实验组优良率达到83.33%高于对照组的60.00%,差异有统计学意义(P<0.05)。术后1个月、3个月、6个月,两组患者膝关节HSS评分较出院时均明显升高,且实验组升高水平较对照组更为明显(P<0.05)。两组患者屈曲挛缩度、膝关节股胫角以及膝关节屈伸活动度均较治疗前有明显改善,且实验组较对照组改善更为显著(P<0.05)。实验组患者总满意度达90.00%高于对照组的63.33%,差异有统计学意义(P<0.05)。两组患者均发生腓总神经麻痹、深部感染等并发症,实验组并发症发生率为6.67%显著低于对照组的26.67%,差异有统计学意义(P<0.05)。结论:全膝关节置换术结合康复功能训练治疗单侧膝内翻合并屈曲畸形临床疗效和修复效果均显著,患者术后膝关节HSS评分、屈曲挛缩度、膝关节股胫角、膝关节屈伸活动度均显著改善,可有效提高患者满意度且并发症较少,值得在临床推广。
基金supported by the National Natural Science Foundation of China(Grant No.61471021)
文摘The process to achieve time synchronization and ranging for a network of mobile nodes is raising a concern among researchers, and hence a variety of joint time synchronization and ranging algorithms have been proposed in recent years. However, few of them handle the case of all-node motion under unknown positions and velocities. This study addresses the problem of determining ranging and time synchronization for a group of nodes moving within a local area. First, we examined several models of clock discrepancy and synchronous two-way ranging. Based upon these models, we present a solution for time synchronization with known positions and velocities. Next, we propose a functional model that jointly estimates the clock skew, clock offset, and time of flight in the absence of a priori knowledge for a pair of mobile nodes. Then, we extend this model to a network-wide time synchronization scheme by way of a global least square estimator. We also discuss the advantages and disadvantages of our model compared to the existing algorithms, and we provide some applicable scenarios as well. Finally, we show that the simulation results verify the validity of our analysis.
基金Supported by the National High Technology Research and Development Program of China(2012AA1406)
文摘An improved measurement algorithm, based upon the theory of two-way time transfer （ TWTT）, is proposed to measure satellites with high speeds. The algorithm makes theoretical analyses and corresponding deductions on a relative motion model of two satellites, and eliminates the measurement error caused by the equipment delay when a satellite moves at a high speed. Theoretical analysis and simulation results demonstrate that in comparison with the conventional TWTT algorithm, the proposed algorithm can significantly enhance the measurement accuracy of the inter-satellite ranging and time synchronization, and the algorithm is more effective with the relative velocity between the satellites and transmitting delay becoming larger.
文摘由STM32和DW1000构成UWB(UltraWideBand)传感器,应用三UWB基站对UWB移动站实现定位,基于UWB测距值建立定位模型。使用基于ToF(Time of Flight)的单边双向测距算法及双边双向测距算法设计测距实验,得到室内测距误差10cm〜30cm,使用基于最小二乘的线性拟合算法校正误差,校正后测距误差在10cm内。经比较,选择单边双向测距算法参与定位。分析了三边定位法、三角形质心定位法、最小二乘定位法、Fang定位法,选择后两种算法进行室内定位实验,并随机取定位样本点分析定位值分布。在普通客厅环境中,两种算法x,y方向的定位误差均在15cm内,最小二乘法定位值分布更均匀。
基金supported by the National Natural Science Foundation of China (Grant No. 60872062)the National Hi-Tech Research and Develop-ment Program of China ("863" Project) (Grant Nos.2007AA12Z336,2009AA12Z313)the Innovation Fund for Astronautics Key-Tech (Grant No. 2009-06)
文摘This paper studies the key techniques of the measurement and communication system for inter-satellite links(ISLs) of global navigation satellite system.A fixed link topology is designed based on the analysis of inter-satellite geometric properties and spatial parameters of the standard Walker24/3/2 constellation.This design can achieve full network coverage with small num-ber of hops,significantly reduce the number of ISLs,and enhance the feasibility and reliability of the system.A new time-division duplex mode,as well as an integrated measurement and communication scheme,is proposed based on the de-signed topology.Furthermore,mathematical formulas,error models,and modification methods regarding two-way ranging and time synchronization algorithms using spread spectrum non-coherent data frame for this new system are comprehensively dis-cussed.Theoretical analysis and simulation studies demonstrate that our design,compared with current GPS systems,has higher ranging and time synchronization precision,improved measurement efficiency,and higher channel utilization ratio and data transmission rate.It has no restrictions of constellation configuration,making it suitable for both MEO and the future MEO/GEO hybrid constellations.The results in this paper can serve as strong technical support for the next generation of GNSS ISL.
