在城市地区发生的大地震可以造成重大人员伤亡,引发社会和经济灾难。地震预警(Earthquake Early Warning,EEW)可以提供秒到分钟的警报,让人们转移到安全区,使工厂停工,车辆减速和刹车。目前世界上只在少数国家使用传统的地震台网和大地...在城市地区发生的大地震可以造成重大人员伤亡,引发社会和经济灾难。地震预警(Earthquake Early Warning,EEW)可以提供秒到分钟的警报,让人们转移到安全区,使工厂停工,车辆减速和刹车。目前世界上只在少数国家使用传统的地震台网和大地测量观测网运行EEW系统。智能手机比传统地震台网更为广泛和普及,它内置了可检测地震的加速度计。我们开发了一种新的测震系统称为MyShake,它利用智能手机内置传感器来收集数据并分析地震。智能手机MyShake系统可以从日常的各种震动中检测到距手机10km或以内的5级地震。这些数据汇集到观测中心,经过一定的算法处理,可以实时测定地震的位置和震级,发出地震预警信息,证明我们的理念是可行的。对没有地震预警系统的区域,MyShake系统可提供地震预警,而对有预警系统的区域,MyShake系统是对原系统预警能力的补充和增强。此外,该系统地震波形记录可以用来提供快速地震烈度图,以评估地震对建筑物的影响,还可以获取地球内部浅层结构图像和地震破裂过程。展开更多
Inspecting and testing code changes typically require a significant amount of developer effort.As a system evolves,developers often create composite changes by mixing multiple development issues,as opposed to addressi...Inspecting and testing code changes typically require a significant amount of developer effort.As a system evolves,developers often create composite changes by mixing multiple development issues,as opposed to addressing one independent issue—an atomic change.Inspecting composite changes often becomes time-consuming and error-prone.To test unrelated edits on composite changes,rerunning all regression tests may require excessive time.To address the problem,we present an interactive technique for change decomposition to support code reviews and regression test selection,called ChgCutter.When a developer specifies code change within a diff patch,ChgCutter partitions composite changes into a set of related atomic changes,which is more cohesive and self-contained regarding the issue being addressed.For composite change inspection,it generates an intermediate program version that only includes a related change subset using program dependence relationships.For cost reduction during regression testing,it safely selects only affected tests responsible for changes to an intermediate version.In the evaluation,we apply ChgCutter to 28 composite changes in four open source projects.ChgCutter partitions these changes with 95.7% accuracy,while selecting affected tests with 89.0% accuracy.We conduct a user study with professional software engineers at PayPal and find that ChgCutter is helpful in understanding and validating composite changes,scaling to industry projects.展开更多
文摘在城市地区发生的大地震可以造成重大人员伤亡,引发社会和经济灾难。地震预警(Earthquake Early Warning,EEW)可以提供秒到分钟的警报,让人们转移到安全区,使工厂停工,车辆减速和刹车。目前世界上只在少数国家使用传统的地震台网和大地测量观测网运行EEW系统。智能手机比传统地震台网更为广泛和普及,它内置了可检测地震的加速度计。我们开发了一种新的测震系统称为MyShake,它利用智能手机内置传感器来收集数据并分析地震。智能手机MyShake系统可以从日常的各种震动中检测到距手机10km或以内的5级地震。这些数据汇集到观测中心,经过一定的算法处理,可以实时测定地震的位置和震级,发出地震预警信息,证明我们的理念是可行的。对没有地震预警系统的区域,MyShake系统可提供地震预警,而对有预警系统的区域,MyShake系统是对原系统预警能力的补充和增强。此外,该系统地震波形记录可以用来提供快速地震烈度图,以评估地震对建筑物的影响,还可以获取地球内部浅层结构图像和地震破裂过程。
文摘Inspecting and testing code changes typically require a significant amount of developer effort.As a system evolves,developers often create composite changes by mixing multiple development issues,as opposed to addressing one independent issue—an atomic change.Inspecting composite changes often becomes time-consuming and error-prone.To test unrelated edits on composite changes,rerunning all regression tests may require excessive time.To address the problem,we present an interactive technique for change decomposition to support code reviews and regression test selection,called ChgCutter.When a developer specifies code change within a diff patch,ChgCutter partitions composite changes into a set of related atomic changes,which is more cohesive and self-contained regarding the issue being addressed.For composite change inspection,it generates an intermediate program version that only includes a related change subset using program dependence relationships.For cost reduction during regression testing,it safely selects only affected tests responsible for changes to an intermediate version.In the evaluation,we apply ChgCutter to 28 composite changes in four open source projects.ChgCutter partitions these changes with 95.7% accuracy,while selecting affected tests with 89.0% accuracy.We conduct a user study with professional software engineers at PayPal and find that ChgCutter is helpful in understanding and validating composite changes,scaling to industry projects.
