时序分析是合成孔径雷达干涉测量(InSAR)的一项关键技术,它被广泛应用于监测广阔地区的地表缓慢形变。这种方法能够提供大范围、大面积的形变监测。其中,StaMPS PS方法凭借适用范围广、开源等优点,受到众多学者的使用。但在时序InSAR中...时序分析是合成孔径雷达干涉测量(InSAR)的一项关键技术,它被广泛应用于监测广阔地区的地表缓慢形变。这种方法能够提供大范围、大面积的形变监测。其中,StaMPS PS方法凭借适用范围广、开源等优点,受到众多学者的使用。但在时序InSAR中,对流层延迟相位会导致形变监测精度的降低,因此,以合肥市为研究区域,分析了经验模型线性改正、GACOS(generic atmospheric correction online service for InSAR)改正和欧洲中期天气预报中心(ECMWF)最新发布的ERA5数据集改正,并对比这3种方法在时序InSAR反演形变速率中的改正效果。通过计算得到研究区的标准差,进行比较分析和验证。其中线性改正、ERA5和GACOS改正后的标准差分别降低了21.71%、16.14%、10.38%。对于合肥区域,这3种方法均可减弱对流层延迟的影响,且精度都有所提高,其中线性改正效果最好,适用性更高,ERA5和GACOS受天气以及地面监测点密度等影响,在该区域改正效果较差。展开更多
It was generally accepted that manuscript maps,as distinct from printed maps,exhibited no signs of printing and were entirely hand-drawn.Western scholars Christopher Terrell and Tony Campbell were the first to break t...It was generally accepted that manuscript maps,as distinct from printed maps,exhibited no signs of printing and were entirely hand-drawn.Western scholars Christopher Terrell and Tony Campbell were the first to break this stereotype in 1987,followed by Catherine Delano-Smith and Chet Van Duzer who discovered a few Renaissance maps and two Qing dynasty maps that showed use of hand stamps.Inspired by these findings,this paper explores the stamped map signs in ten Chinese maps,three Japanese maps,and three Korean maps.By analyzing each map and each type of stamp,this paper provides more examples of this research,broadens the research horizons and geographical area,and demonstrates that use of stamps in manuscript maps was invented independently among people of different regions and civilizations as a result of human nature.展开更多
安全生产事故往往由多组织交互、多因素耦合造成,事故原因涉及多个组织。为预防和遏制多组织生产安全事故的发生,基于系统理论事故建模与过程模型(Systems-Theory Accident Modeling and Process,STAMP)、24Model,构建一种用于多组织事...安全生产事故往往由多组织交互、多因素耦合造成,事故原因涉及多个组织。为预防和遏制多组织生产安全事故的发生,基于系统理论事故建模与过程模型(Systems-Theory Accident Modeling and Process,STAMP)、24Model,构建一种用于多组织事故分析的方法,并以青岛石油爆炸事故为例进行事故原因分析。结果显示:STAMP-24Model可以分组织,分层次且有效、全面、详细地分析涉及多个组织的事故原因,探究多组织之间的交互关系;对事故进行动态演化分析,可得到各组织不安全动作耦合关系与形成的事故失效链及管控失效路径,进而为预防多组织事故提供思路和参考。展开更多
与传统列控系统相比,全自动无人驾驶运营场景更加复杂多变,潜在的危险及致因具有更强的隐蔽性和复杂性,给运营安全带来了新的挑战。针对以上问题,提出一种STAMP(Systems-Theoretic Accident Model and Process)与模型检验相结合的复杂...与传统列控系统相比,全自动无人驾驶运营场景更加复杂多变,潜在的危险及致因具有更强的隐蔽性和复杂性,给运营安全带来了新的挑战。针对以上问题,提出一种STAMP(Systems-Theoretic Accident Model and Process)与模型检验相结合的复杂运营场景安全验证方法。首先,基于STAMP理论构建运营场景分层控制结构模型,辨识潜在的不安全控制行为、分析危险致因和安全约束;其次,定义分层控制结构模型与安全状态机模型间的基本转换规则,基于分层控制结构模型、安全约束和转换规则,构建运营场景安全状态机模型;最后,针对提取的安全约束,利用数据流图建立安全属性验证模型,结合模型检验技术,对运营场景安全状态机模型进行形式化验证。以全自动无人驾驶运营场景中列车自动进站停车为例,对方法进行验证分析。结果表明,当STAMP理论提取的安全约束通过了场景安全状态机模型的验证时,表示在该场景中对应的不安全控制行为没有发生且不导致相应危险。该方法结合系统安全分析与形式化建模验证的优势,降低了运营场景建模的难度,构建的运营场景形式化模型满足系统安全约束,可以作为全自动无人驾驶系统安全设计和安全改进的重要基础。展开更多
To address the common issues of wrinkling,tearing,and uneven wall thickness in the actual sheet metal stamp-ing process of the outer ring of needle roller bearings,this study analyzes critical technical indicators suc...To address the common issues of wrinkling,tearing,and uneven wall thickness in the actual sheet metal stamp-ing process of the outer ring of needle roller bearings,this study analyzes critical technical indicators such asforming limits,thickness distribution,and principal strains in the forming process in detail.Three-dimensionalmodels of the concave and convex dies were constructed.The effects of different process parameters,includingstamping speed,edge pressure,sheet metal thickness,and friction coefficient,on the quality of the forming partswere investigated by varying these parameters.Subsequently,the orthogonal experimental method was used todetermine an optimal experimental group from multiple sets of experiments.It was found that under the processparameters of a stamping speed of 3000 mm/s,edge pressure of 2000 N,sheet metal thickness of 0.9 mm,andfriction coefficient of 0.125,the forming quality of the outer ring of the bearing is ideal.展开更多
Accidents in engineered systems are usually generated by complex socio-technical factors.It is beneficial to investigate the increasing complexity and coupling of these factors from the perspective of system safety.Ba...Accidents in engineered systems are usually generated by complex socio-technical factors.It is beneficial to investigate the increasing complexity and coupling of these factors from the perspective of system safety.Based on system and control theories,System-Theoretic Accident Model and Processes(STAMP)is a widely recognized approach for accident analysis.In this paper,we propose a STAMP-Game model to analyze accidents in oil and gas storage and transportation systems.Stakeholders in accident analysis by STAMP can be regarded as players of a game.Game theory can,thus,be adopted in accident analysis to depict the competition and cooperation between stakeholders.Subsequently,we established a game model to study the strategies of both supervisory and supervised entities.The obtained results demonstrate that the proposed game model allows for identifying the effectiveness deficiency of the supervisory entity,and the safety and protection altitudes of the supervised entity.The STAMP-Game model can generate quantitative parameters for supporting the behavior and strategy selections of the supervisory and supervised entities.The quantitative data obtained can be used to guide the safety improvement,to reduce the costs of safety regulation violation and accident risk.展开更多
为分析化学品船智能液货系统的安全性,采用系统理论事故模型与过程(System-Theoretic Accident Model and Processes, STAMP)方法,构建了化学品船智能液货系统控制反馈模型;基于系统理论过程分析(System-Theoretic Process Analysis, ST...为分析化学品船智能液货系统的安全性,采用系统理论事故模型与过程(System-Theoretic Accident Model and Processes, STAMP)方法,构建了化学品船智能液货系统控制反馈模型;基于系统理论过程分析(System-Theoretic Process Analysis, STPA),确定系统级事故,识别不安全控制行为并分析不安全控制行为关键致因;将不安全控制行为作为风险因素,利用三角模糊数对不安全控制行为风险进行量化。结果表明,26种不安全控制行为中,泵管阀动态调节、人员监测、数据采集、货品相容性判定等因素对风险影响程度较高。该分析结果可为化学品船智能液货系统的应用和安全管理提供参考。展开更多
文摘时序分析是合成孔径雷达干涉测量(InSAR)的一项关键技术,它被广泛应用于监测广阔地区的地表缓慢形变。这种方法能够提供大范围、大面积的形变监测。其中,StaMPS PS方法凭借适用范围广、开源等优点,受到众多学者的使用。但在时序InSAR中,对流层延迟相位会导致形变监测精度的降低,因此,以合肥市为研究区域,分析了经验模型线性改正、GACOS(generic atmospheric correction online service for InSAR)改正和欧洲中期天气预报中心(ECMWF)最新发布的ERA5数据集改正,并对比这3种方法在时序InSAR反演形变速率中的改正效果。通过计算得到研究区的标准差,进行比较分析和验证。其中线性改正、ERA5和GACOS改正后的标准差分别降低了21.71%、16.14%、10.38%。对于合肥区域,这3种方法均可减弱对流层延迟的影响,且精度都有所提高,其中线性改正效果最好,适用性更高,ERA5和GACOS受天气以及地面监测点密度等影响,在该区域改正效果较差。
文摘It was generally accepted that manuscript maps,as distinct from printed maps,exhibited no signs of printing and were entirely hand-drawn.Western scholars Christopher Terrell and Tony Campbell were the first to break this stereotype in 1987,followed by Catherine Delano-Smith and Chet Van Duzer who discovered a few Renaissance maps and two Qing dynasty maps that showed use of hand stamps.Inspired by these findings,this paper explores the stamped map signs in ten Chinese maps,three Japanese maps,and three Korean maps.By analyzing each map and each type of stamp,this paper provides more examples of this research,broadens the research horizons and geographical area,and demonstrates that use of stamps in manuscript maps was invented independently among people of different regions and civilizations as a result of human nature.
文摘安全生产事故往往由多组织交互、多因素耦合造成,事故原因涉及多个组织。为预防和遏制多组织生产安全事故的发生,基于系统理论事故建模与过程模型(Systems-Theory Accident Modeling and Process,STAMP)、24Model,构建一种用于多组织事故分析的方法,并以青岛石油爆炸事故为例进行事故原因分析。结果显示:STAMP-24Model可以分组织,分层次且有效、全面、详细地分析涉及多个组织的事故原因,探究多组织之间的交互关系;对事故进行动态演化分析,可得到各组织不安全动作耦合关系与形成的事故失效链及管控失效路径,进而为预防多组织事故提供思路和参考。
文摘与传统列控系统相比,全自动无人驾驶运营场景更加复杂多变,潜在的危险及致因具有更强的隐蔽性和复杂性,给运营安全带来了新的挑战。针对以上问题,提出一种STAMP(Systems-Theoretic Accident Model and Process)与模型检验相结合的复杂运营场景安全验证方法。首先,基于STAMP理论构建运营场景分层控制结构模型,辨识潜在的不安全控制行为、分析危险致因和安全约束;其次,定义分层控制结构模型与安全状态机模型间的基本转换规则,基于分层控制结构模型、安全约束和转换规则,构建运营场景安全状态机模型;最后,针对提取的安全约束,利用数据流图建立安全属性验证模型,结合模型检验技术,对运营场景安全状态机模型进行形式化验证。以全自动无人驾驶运营场景中列车自动进站停车为例,对方法进行验证分析。结果表明,当STAMP理论提取的安全约束通过了场景安全状态机模型的验证时,表示在该场景中对应的不安全控制行为没有发生且不导致相应危险。该方法结合系统安全分析与形式化建模验证的优势,降低了运营场景建模的难度,构建的运营场景形式化模型满足系统安全约束,可以作为全自动无人驾驶系统安全设计和安全改进的重要基础。
基金supported by the China Postdoctoral Science Foundation(Grant No.2022M721395)the National Natural Science Foundation of China(Grant No.72072089).
文摘To address the common issues of wrinkling,tearing,and uneven wall thickness in the actual sheet metal stamp-ing process of the outer ring of needle roller bearings,this study analyzes critical technical indicators such asforming limits,thickness distribution,and principal strains in the forming process in detail.Three-dimensionalmodels of the concave and convex dies were constructed.The effects of different process parameters,includingstamping speed,edge pressure,sheet metal thickness,and friction coefficient,on the quality of the forming partswere investigated by varying these parameters.Subsequently,the orthogonal experimental method was used todetermine an optimal experimental group from multiple sets of experiments.It was found that under the processparameters of a stamping speed of 3000 mm/s,edge pressure of 2000 N,sheet metal thickness of 0.9 mm,andfriction coefficient of 0.125,the forming quality of the outer ring of the bearing is ideal.
基金supported by the National Natural Science Foundation of China(Grant No.52004030)the R&D Program of Beijing Municipal Education Commission(Grant No.KM202310016003)the Exchange Program of High-end Foreign Experts of Ministry of Science and Technology,China(Grant No.G2022178013L)。
文摘Accidents in engineered systems are usually generated by complex socio-technical factors.It is beneficial to investigate the increasing complexity and coupling of these factors from the perspective of system safety.Based on system and control theories,System-Theoretic Accident Model and Processes(STAMP)is a widely recognized approach for accident analysis.In this paper,we propose a STAMP-Game model to analyze accidents in oil and gas storage and transportation systems.Stakeholders in accident analysis by STAMP can be regarded as players of a game.Game theory can,thus,be adopted in accident analysis to depict the competition and cooperation between stakeholders.Subsequently,we established a game model to study the strategies of both supervisory and supervised entities.The obtained results demonstrate that the proposed game model allows for identifying the effectiveness deficiency of the supervisory entity,and the safety and protection altitudes of the supervised entity.The STAMP-Game model can generate quantitative parameters for supporting the behavior and strategy selections of the supervisory and supervised entities.The quantitative data obtained can be used to guide the safety improvement,to reduce the costs of safety regulation violation and accident risk.
文摘为分析化学品船智能液货系统的安全性,采用系统理论事故模型与过程(System-Theoretic Accident Model and Processes, STAMP)方法,构建了化学品船智能液货系统控制反馈模型;基于系统理论过程分析(System-Theoretic Process Analysis, STPA),确定系统级事故,识别不安全控制行为并分析不安全控制行为关键致因;将不安全控制行为作为风险因素,利用三角模糊数对不安全控制行为风险进行量化。结果表明,26种不安全控制行为中,泵管阀动态调节、人员监测、数据采集、货品相容性判定等因素对风险影响程度较高。该分析结果可为化学品船智能液货系统的应用和安全管理提供参考。
