Monte Carlo simulation was applied to Assembly Success Bate (ASK) analyses. ASR of two peg-in-hole robot assemblies was used as an example by taking component parts' sizes, manufacturing tolerances and robot repea...Monte Carlo simulation was applied to Assembly Success Bate (ASK) analyses. ASR of two peg-in-hole robot assemblies was used as an example by taking component parts' sizes, manufacturing tolerances and robot repeatability into account. A statistic arithmetic expression was proposed and deduced in this paper, which offers an alternative method of estimating the accuracy of ASR, without having to repeat the simulations. This statistic method also helps to choose a suitable sample size, if error reduction is desired. Monte Carlo simulation results demonstrated the feasibility of the method.展开更多
目的评价冠状动脉慢性完全闭塞病变(chronic total occlusion,CTO)侧支循环的形成情况,对影响侧支循环建立的因素进行探讨。方法连续搜集2004年1月至2008年12月上海市中山医院1485例冠状动脉造影提示完全闭塞病变并确认为CTO(闭塞时间&g...目的评价冠状动脉慢性完全闭塞病变(chronic total occlusion,CTO)侧支循环的形成情况,对影响侧支循环建立的因素进行探讨。方法连续搜集2004年1月至2008年12月上海市中山医院1485例冠状动脉造影提示完全闭塞病变并确认为CTO(闭塞时间>3个月)病变者638例,根据冠状动脉造影结果采用Rentrop法评价侧支循环的开放情况,将侧支循环积分2、3级判断为侧支循环良好,侧支循环积分0、1级判断为侧支循环不良;对两组患者在临床影响因素、病变影像特征、介入治疗资料等进行分析。结果两组患者年龄(63.6±10.7)岁比(66.5±11.2)岁,t=3.638,P<0.05;合并既往明确心肌梗死史(32.8%比39.5%,χ2=2.043,P<0.05);中重度吸烟史44.1%比59.5%,χ2=15.277,P<0.01;高尿酸水平(355.79±92.69)mmol/L比(370.94±94.81)mmol/L,t=2.697,P<0.05及空腹血糖水平升高(5.51±1.38)mmol/L比(6.67±1.41)mmol/L,t=2.299,P<0.05;开口闭塞病变29.8%比20.7%,χ2=6.927,P<0.01及病变近端中重度迂曲者19.1%比26.2%,χ2=4.551,P<0.05,多出现侧支循环不良;经多元回归分析,既往有中重度吸烟史(OR:0.191,P<0.05,95%CI:0.052～0.699)、空腹血糖水平升高(OR:0.377,P<0.05,95%CI:0.092～0.989)为CTO病变侧支循环形成不良的独立预测因素;而闭塞血管及位置、心绞痛病程、既往心梗史等方面差异无统计学意义。结论本研究显示中重度吸烟史、空腹血糖水平升高对于CTO病变侧支循环形成具有独立的负向预测作用,而心绞痛病程、心肌梗死等因素对其无明确影响作用。展开更多
文摘Monte Carlo simulation was applied to Assembly Success Bate (ASK) analyses. ASR of two peg-in-hole robot assemblies was used as an example by taking component parts' sizes, manufacturing tolerances and robot repeatability into account. A statistic arithmetic expression was proposed and deduced in this paper, which offers an alternative method of estimating the accuracy of ASR, without having to repeat the simulations. This statistic method also helps to choose a suitable sample size, if error reduction is desired. Monte Carlo simulation results demonstrated the feasibility of the method.
文摘目的评价冠状动脉慢性完全闭塞病变(chronic total occlusion,CTO)侧支循环的形成情况,对影响侧支循环建立的因素进行探讨。方法连续搜集2004年1月至2008年12月上海市中山医院1485例冠状动脉造影提示完全闭塞病变并确认为CTO(闭塞时间>3个月)病变者638例,根据冠状动脉造影结果采用Rentrop法评价侧支循环的开放情况,将侧支循环积分2、3级判断为侧支循环良好,侧支循环积分0、1级判断为侧支循环不良;对两组患者在临床影响因素、病变影像特征、介入治疗资料等进行分析。结果两组患者年龄(63.6±10.7)岁比(66.5±11.2)岁,t=3.638,P<0.05;合并既往明确心肌梗死史(32.8%比39.5%,χ2=2.043,P<0.05);中重度吸烟史44.1%比59.5%,χ2=15.277,P<0.01;高尿酸水平(355.79±92.69)mmol/L比(370.94±94.81)mmol/L,t=2.697,P<0.05及空腹血糖水平升高(5.51±1.38)mmol/L比(6.67±1.41)mmol/L,t=2.299,P<0.05;开口闭塞病变29.8%比20.7%,χ2=6.927,P<0.01及病变近端中重度迂曲者19.1%比26.2%,χ2=4.551,P<0.05,多出现侧支循环不良;经多元回归分析,既往有中重度吸烟史(OR:0.191,P<0.05,95%CI:0.052～0.699)、空腹血糖水平升高(OR:0.377,P<0.05,95%CI:0.092～0.989)为CTO病变侧支循环形成不良的独立预测因素;而闭塞血管及位置、心绞痛病程、既往心梗史等方面差异无统计学意义。结论本研究显示中重度吸烟史、空腹血糖水平升高对于CTO病变侧支循环形成具有独立的负向预测作用,而心绞痛病程、心肌梗死等因素对其无明确影响作用。
