This paper presents autonomous docking of an inhouse built resident Remotely Operated Vehicle(ROV),called Rover ROV,through acoustic guided techniques.A novel cage-type docking station has been developed.The docking s...This paper presents autonomous docking of an inhouse built resident Remotely Operated Vehicle(ROV),called Rover ROV,through acoustic guided techniques.A novel cage-type docking station has been developed.The docking station can be placed on a deep-sea lander,taking the Rover ROV to the seafloor.Instead of using vision-based pose estimation techniques and expensive navigation sensors,the Rover ROV docking adopts an ultra-short baseline(USBL)and low-cost inertial sensors to build an adaptive fault-tolerant integrated navigation system.To solve the problem of sonar-based failure positioning,the measurement residuals are exploited to detect measurement faults.Then,an adaptation scheme for estimating the statistical characteristics of noise in real-time is proposed,which can provide robust and smooth positioning results.It is more suitable for a compact and low-cost deep-sea resident ROV.Field experiments have been conducted successfully in the Qiandao Lake and the South China Sea area with a depth of 3000 m,respectively.The experimental results show that the functionality of autonomous docking has been achieved.Under the guidance of the navigation system,the Rover ROV can autonomously and efficiently return to the docking station within a range of 100 m even when the amounts of outliers exist in the acoustic positioning data.These achievements can be applied to current ROVs by an easy retrofit.展开更多
The consensus of the automotive industry and traffic management authorities is that autonomous vehicles must follow the same traffic laws as human drivers.Using formal or digital methods,natural language traffic rules...The consensus of the automotive industry and traffic management authorities is that autonomous vehicles must follow the same traffic laws as human drivers.Using formal or digital methods,natural language traffic rules can be translated into machine language and used by autonomous vehicles.In this paper,a translation flow is designed.Beyond the translation,a deeper examination is required,because the semantics of natural languages are rich and complex,and frequently contain hidden assumptions.The issue of how to ensure that digital rules are accurate and consistent with the original intent of the traffic rules they represent is both significant and unresolved.In response,we propose a method of formal verification that combines equivalence verification with model checking.Reasonable and reassuring digital traffic rules can be obtained by utilizing the proposed traffic rule digitization flow and verification method.In addition,we offer a number of simulation applications that employ digital traffic rules to assess vehicle violations.The experimental findings indicate that our digital rules utilizing metric temporal logic(MTL)can be easily incorporated into simulation platforms and autonomous driving systems(ADS).展开更多
Based on the Tibet Autonomous Region's statistic yearbooks and the data fromthe two household surveys in 2002 and 2004, this paper has comprehensively analyzed the pattern ofchanges on the farmers and herdsmen'...Based on the Tibet Autonomous Region's statistic yearbooks and the data fromthe two household surveys in 2002 and 2004, this paper has comprehensively analyzed the pattern ofchanges on the farmers and herdsmen's income sources in the Tibet Autonomous Region since 1990 withthe main findings as follows; (1) The change of income from the labor payment is the fastest; (2)There is no regular pattern of income variation for the household economic activities, the farmersand herdsmen's household incomegeneration projects are impacted by the elements like prices andreturns, and there is a lack of appropriate direction; (3) The income structure of labor paymentshows that the income from the farmers and herdsmen working outside grows fastest; (4) The incomefrom the farmers and herdsmen's labor payment correlate positively to their net income per capita;(5) From the perspective of the variation by region, labor payment income has changed fastest in thecounties of Rutok, Nyerong and Khangmar comparedthe data from the household survey in 2002 withthat of 2004.展开更多
目的探讨多模态影像融合(multimodal image fusion,MMIF)辅助以案例为基础的教学法(case based learning,CBL)对心血管内科住院医师规范化培训(简称住培)效果的影响。方法选择2021年10月—2022年10月在南京医科大学第一附属医院心血管...目的探讨多模态影像融合(multimodal image fusion,MMIF)辅助以案例为基础的教学法(case based learning,CBL)对心血管内科住院医师规范化培训(简称住培)效果的影响。方法选择2021年10月—2022年10月在南京医科大学第一附属医院心血管内科轮转的住院医师为研究对象,共60名。根据不同轮转时间将2021年10月—2022年3月进行轮转医师设为对照组,共27名;将2022年4月—2022年10月进行轮转的医师设为观察组,共33名。对照组予以常规教学模式,观察组行MMIF辅助CBL教学法,2组教学均持续2个月。于教学前后,评估2组的理论知识、实践能力、自主学习能力和临床思维能力;评估2组医师的教学满意度。结果观察组满意度高于对照组(96.67%vs.77.78%),差异有统计学意义(P<0.05)。带教后,2组理论知识、实践能力评分、自主学习能力和临床思维能力评分均升高,且观察组高于对照组,差异有统计学意义(P<0.05)。结论MMIF辅助CBL教学法在心血管内科住培中的效果较好,可提高学员的理论成绩、实践能力和自主学习能力,培养其临床思维能力。展开更多
Drivers are not far-sighted when they execute lane-changing manipulation.To address this issue,this study proposes a rule to improve vehicles'lane-changing decisions with accurate information of surrounding vehicl...Drivers are not far-sighted when they execute lane-changing manipulation.To address this issue,this study proposes a rule to improve vehicles'lane-changing decisions with accurate information of surrounding vehicles(e.g.time headway)-More specifically,connected and autonomous vehicles(CAVs)change lanes in advance if they find severer flow reducing in the lanes,while CAVs should maintain the car-following state if the variations of traffc flow in all lanes have a similar trend.To ilustrate the idea,this study frst calibrates two classic car-following models and a lane-changing model,and then conducts numerical simulations to illustrate the short-sighted decision of drivers.The study incorporates the idea into a lane-changing decision rule by changing the lane-changing model's pa-rameter,and conducts numerical tests to evaluate the effectiveness of the lane-changing decision rule in a multi-lane highway with a bottleneck.The results of this study indicate that the new lane-changing decision rule can substantially improve the throughput of the traffic flow,especially when the inflow exceeds the remaining capacity of the road.The lane-changing rule and results can bring insights into the control of CAVs,as well as the driver assistance system in connected vehicles.展开更多
基金financially supported by the National Key R&D Program of China (Grant No. 2017YFC0306402)the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDA22040102)
文摘This paper presents autonomous docking of an inhouse built resident Remotely Operated Vehicle(ROV),called Rover ROV,through acoustic guided techniques.A novel cage-type docking station has been developed.The docking station can be placed on a deep-sea lander,taking the Rover ROV to the seafloor.Instead of using vision-based pose estimation techniques and expensive navigation sensors,the Rover ROV docking adopts an ultra-short baseline(USBL)and low-cost inertial sensors to build an adaptive fault-tolerant integrated navigation system.To solve the problem of sonar-based failure positioning,the measurement residuals are exploited to detect measurement faults.Then,an adaptation scheme for estimating the statistical characteristics of noise in real-time is proposed,which can provide robust and smooth positioning results.It is more suitable for a compact and low-cost deep-sea resident ROV.Field experiments have been conducted successfully in the Qiandao Lake and the South China Sea area with a depth of 3000 m,respectively.The experimental results show that the functionality of autonomous docking has been achieved.Under the guidance of the navigation system,the Rover ROV can autonomously and efficiently return to the docking station within a range of 100 m even when the amounts of outliers exist in the acoustic positioning data.These achievements can be applied to current ROVs by an easy retrofit.
文摘The consensus of the automotive industry and traffic management authorities is that autonomous vehicles must follow the same traffic laws as human drivers.Using formal or digital methods,natural language traffic rules can be translated into machine language and used by autonomous vehicles.In this paper,a translation flow is designed.Beyond the translation,a deeper examination is required,because the semantics of natural languages are rich and complex,and frequently contain hidden assumptions.The issue of how to ensure that digital rules are accurate and consistent with the original intent of the traffic rules they represent is both significant and unresolved.In response,we propose a method of formal verification that combines equivalence verification with model checking.Reasonable and reassuring digital traffic rules can be obtained by utilizing the proposed traffic rule digitization flow and verification method.In addition,we offer a number of simulation applications that employ digital traffic rules to assess vehicle violations.The experimental findings indicate that our digital rules utilizing metric temporal logic(MTL)can be easily incorporated into simulation platforms and autonomous driving systems(ADS).
文摘Based on the Tibet Autonomous Region's statistic yearbooks and the data fromthe two household surveys in 2002 and 2004, this paper has comprehensively analyzed the pattern ofchanges on the farmers and herdsmen's income sources in the Tibet Autonomous Region since 1990 withthe main findings as follows; (1) The change of income from the labor payment is the fastest; (2)There is no regular pattern of income variation for the household economic activities, the farmersand herdsmen's household incomegeneration projects are impacted by the elements like prices andreturns, and there is a lack of appropriate direction; (3) The income structure of labor paymentshows that the income from the farmers and herdsmen working outside grows fastest; (4) The incomefrom the farmers and herdsmen's labor payment correlate positively to their net income per capita;(5) From the perspective of the variation by region, labor payment income has changed fastest in thecounties of Rutok, Nyerong and Khangmar comparedthe data from the household survey in 2002 withthat of 2004.
文摘目的探讨多模态影像融合(multimodal image fusion,MMIF)辅助以案例为基础的教学法(case based learning,CBL)对心血管内科住院医师规范化培训(简称住培)效果的影响。方法选择2021年10月—2022年10月在南京医科大学第一附属医院心血管内科轮转的住院医师为研究对象,共60名。根据不同轮转时间将2021年10月—2022年3月进行轮转医师设为对照组,共27名;将2022年4月—2022年10月进行轮转的医师设为观察组,共33名。对照组予以常规教学模式,观察组行MMIF辅助CBL教学法,2组教学均持续2个月。于教学前后,评估2组的理论知识、实践能力、自主学习能力和临床思维能力;评估2组医师的教学满意度。结果观察组满意度高于对照组(96.67%vs.77.78%),差异有统计学意义(P<0.05)。带教后,2组理论知识、实践能力评分、自主学习能力和临床思维能力评分均升高,且观察组高于对照组,差异有统计学意义(P<0.05)。结论MMIF辅助CBL教学法在心血管内科住培中的效果较好,可提高学员的理论成绩、实践能力和自主学习能力,培养其临床思维能力。
基金This work was supported by the National Natural Science Foundation of China(Grants No.72271248,71801227,72201149)the Nation Key Research and Develop-ment Program of China(Grant No.2020YFB1600400)+1 种基金the Higher-end Think-Tank Project of Central South University(Grant No.2022znzk07)the China Postdoctoral Science Foundation(Grant No.2022M711818).
文摘Drivers are not far-sighted when they execute lane-changing manipulation.To address this issue,this study proposes a rule to improve vehicles'lane-changing decisions with accurate information of surrounding vehicles(e.g.time headway)-More specifically,connected and autonomous vehicles(CAVs)change lanes in advance if they find severer flow reducing in the lanes,while CAVs should maintain the car-following state if the variations of traffc flow in all lanes have a similar trend.To ilustrate the idea,this study frst calibrates two classic car-following models and a lane-changing model,and then conducts numerical simulations to illustrate the short-sighted decision of drivers.The study incorporates the idea into a lane-changing decision rule by changing the lane-changing model's pa-rameter,and conducts numerical tests to evaluate the effectiveness of the lane-changing decision rule in a multi-lane highway with a bottleneck.The results of this study indicate that the new lane-changing decision rule can substantially improve the throughput of the traffic flow,especially when the inflow exceeds the remaining capacity of the road.The lane-changing rule and results can bring insights into the control of CAVs,as well as the driver assistance system in connected vehicles.
