中国列车控制系统(Chinese train control system,CTCS)作为一种安全苛求系统,使用前需要经过严格的安全分析和测试。对我国铁路客运干线主要采用的CTCS-3级列控系统而言,由于传统的安全分析方法主要关注单一场景,因而对其复合场景的安...中国列车控制系统(Chinese train control system,CTCS)作为一种安全苛求系统,使用前需要经过严格的安全分析和测试。对我国铁路客运干线主要采用的CTCS-3级列控系统而言,由于传统的安全分析方法主要关注单一场景,因而对其复合场景的安全性分析存在欠缺。此外,CTCS-3列控系统对控制时序有严格要求,现有安全分析方法难以有效解决该问题。为解决上述问题,采用基于系统理论的过程分析方法,以便更全面、更准确地分析CTCS-3级列控系统的安全性。首先,在分析CTCS-3级列控系统典型运营场景的基础上,提取由列控系统直接控车的运营场景,并建立分层控制结构模型;其次,结合时序逻辑辨识运营场景的不恰当控制行为,并将各场景中互不冲突的不恰当控制行为组合成复合场景;最后,对复合场景进行分析,辨识导致不恰当控制行为的控制缺陷。仿真结果表明:系统理论的过程分析方法可以实现对CTCS-3级列控系统复合场景功能的安全性分析。展开更多
The age, growth and maturation of Sthenoteuthis oualaniensis were determined with statolith data collected with a light purse seine from the Bashi Channel of central Pacific Ocean. The estimated longevity of the squid...The age, growth and maturation of Sthenoteuthis oualaniensis were determined with statolith data collected with a light purse seine from the Bashi Channel of central Pacific Ocean. The estimated longevity of the squid was no more than 6 months for females, and no more than 5 months for males. Growth in mantle length(ML) was best described by logistic models for both females and males, while growth in body weight(BW) was best fitted by power curves. The maximum absolute growth rate(AGR) and instantaneous growth rate(IGR) in ML or BW both occurred at 91–105 days for females and 76–90 days for males. Back calculated hatching dates were from October to January, with a peak in December, although the short duration of sampling date might have had an influence on the result. The lower percentage of mature females(37.2%) suggested that the study area during the sampling date was not a spawning ground for the species. Size and age at first maturity were 183 mm ML and 136 days for females, whereas they were 156 mm ML and 85 days for males.展开更多
文摘中国列车控制系统(Chinese train control system,CTCS)作为一种安全苛求系统,使用前需要经过严格的安全分析和测试。对我国铁路客运干线主要采用的CTCS-3级列控系统而言,由于传统的安全分析方法主要关注单一场景,因而对其复合场景的安全性分析存在欠缺。此外,CTCS-3列控系统对控制时序有严格要求,现有安全分析方法难以有效解决该问题。为解决上述问题,采用基于系统理论的过程分析方法,以便更全面、更准确地分析CTCS-3级列控系统的安全性。首先,在分析CTCS-3级列控系统典型运营场景的基础上,提取由列控系统直接控车的运营场景,并建立分层控制结构模型;其次,结合时序逻辑辨识运营场景的不恰当控制行为,并将各场景中互不冲突的不恰当控制行为组合成复合场景;最后,对复合场景进行分析,辨识导致不恰当控制行为的控制缺陷。仿真结果表明:系统理论的过程分析方法可以实现对CTCS-3级列控系统复合场景功能的安全性分析。
基金supported by the Natural National Science Foundation of China (Nos. 41306127 and 41276156)the Innovation Program of Shanghai Municipal Education Commission (No.13YZ091)+1 种基金the Ph.D Programs Foundation of Ministry of Education of China (No. 20133104120001)Shanghai Universities First-class Disciplines Project (Fisheries A)
文摘The age, growth and maturation of Sthenoteuthis oualaniensis were determined with statolith data collected with a light purse seine from the Bashi Channel of central Pacific Ocean. The estimated longevity of the squid was no more than 6 months for females, and no more than 5 months for males. Growth in mantle length(ML) was best described by logistic models for both females and males, while growth in body weight(BW) was best fitted by power curves. The maximum absolute growth rate(AGR) and instantaneous growth rate(IGR) in ML or BW both occurred at 91–105 days for females and 76–90 days for males. Back calculated hatching dates were from October to January, with a peak in December, although the short duration of sampling date might have had an influence on the result. The lower percentage of mature females(37.2%) suggested that the study area during the sampling date was not a spawning ground for the species. Size and age at first maturity were 183 mm ML and 136 days for females, whereas they were 156 mm ML and 85 days for males.
