With the growing rate of automated vehicles(AVs)at the lower level of automation,the experimental tests are also in progress with vehicles at higher levels.In the absence of extended digital infrastructures and deploy...With the growing rate of automated vehicles(AVs)at the lower level of automation,the experimental tests are also in progress with vehicles at higher levels.In the absence of extended digital infrastructures and deployment of level 5 full automated vehicles,the physical infrastructure is required to maintain a fundamental role to enable their introduction in public roads.This paper focuses on lane support system(LSS)whose operational design domain(ODD)is strongly connected to the road characteristics and conditions.An experimental test was carried out with a state of the art,and LSS and advanced technologies were used for road monitoring on different roads under various environmental conditions including dry,wet pavements and rain.We applied the generalized estimation equation for logistic regression to account within-cluster homogeneity which is induced by repeated measures on the same road sections.Statistical models allow the identification of variables that are significant for the LSS fault probability among various effects of road features including marking,pavement distress,weather conditions,horizontal curvature,and cross section.Results pointed out the relevance of the wet retro-reflection of marking(RLw)and the horizontal curvature in the definition of ODD for LSS.Threshold values have been proposed for the tested LSS.Wet pavement doesn’t affect the LSS performance when compared to the dry condition.Rain was shown to be critical even with very good road characteristics.展开更多
Ergonomic reliability plays a significant role in the safe operation of devices.With the spread of infectious diseases around the world,in work environments with high loads and high infection rates,medical staff work ...Ergonomic reliability plays a significant role in the safe operation of devices.With the spread of infectious diseases around the world,in work environments with high loads and high infection rates,medical staff work in a state of high self-protection.The use of visual display terminal(VDT)for medical equipment has undergone fundamental changes,and the traditional medical equipment human-machine interface design needs to be improved.After the completion of design and development,a VDT design enters the experimental testing stage,which has significant limitations for simulating the work of medical staff in the high-load and high-infection environments.The testing cost is high,and subjects face harsh conditions;thus,an ergonomic reliability model that can predict the use of VDT in such special high-infection and high-load circumstances must be established.An ergonomic reliability model based on an improved backpropagation neural network(BPNN)and human cognition reliability(HCR)is proposed for predicting and evaluating operation flows according tomedical equipment VDTs.Firstly,a small data sample can be used to train BPNN to generate a network that can ensure suitable accuracy.To prevent the model from falling into local optimal solutions,the bat algorithm is introduced to improve the BPNN.Compared to a traditional BPNN,the superiority of the improved BPNN is clearly demonstrated.Secondly,the HCR method is used to analyze and highlight changes in the human factor reliability of VDTs for medical equipment in different time processes and operating processes according to BPNN prediction results,to provide a reference for selecting the optimalmethod.Finally,the validity and availability of the proposedmethod are verified through an eye tracker experiment and statistical analysis results.展开更多
On March 31, in accordance with the typical design requirements of the State Grid, the f irst large electric vehicle (EV) charging station, built by the North China Grid,
The desulfuration system in the second phase project of Sanhe Power Plant is the first such system that adopts in-duct FGD with no-bypass design by domestic power plants.Different from that of the conventional FGD wit...The desulfuration system in the second phase project of Sanhe Power Plant is the first such system that adopts in-duct FGD with no-bypass design by domestic power plants.Different from that of the conventional FGD with bypass design,a running control mode,which is important for the security of the absorbing tower within the designed ranges,shall be made to ensure the flue gas temperature and dust concentration at the inlet of the absorbing tower.The stable running of the system shows that the control mode is feasible.展开更多
IPv6 is the foundation of the development of Next Generation Internet (NGI). An IPv6 network management and operations support system is necessary for real operable NGI. Presently there are no approved standards yet a...IPv6 is the foundation of the development of Next Generation Internet (NGI). An IPv6 network management and operations support system is necessary for real operable NGI. Presently there are no approved standards yet and relevant equipment interfaces are not perfect. A Network Management System (NMS) at the network layer helps implement the integrated management of a network with equipment from multiple vendors, including the network resources and topology, end-to-end network performance, network failures and customer Service Level Agreement (SLA) management. Though the NMS will finally realize pure IPv6 network management, it must be accommodated to the management of relevant IPv4 equipment. Therefore, modularized and layered structure is adopted for the NMS in order to implement its smooth transition.展开更多
The recovery of low temperature heat sources is a hot topic in the world.The ORC system can effectively use the low temperature heat source.As its main output device,the performance of the turbine is very important.Th...The recovery of low temperature heat sources is a hot topic in the world.The ORC system can effectively use the low temperature heat source.As its main output device,the performance of the turbine is very important.The single stage transonic turbine has the characteristics of small size and large output power.In this paper,the complete design process of a transonic centrifugal turbine with R245fa in low working temperature condition is introduced.At the design conditions,the shaft power and the wheel efficiency of the centrifugal turbine can reach 1.12 MW and 83.61%,respectively.In addition,a thermodynamic ORC cycle is presented and the off-design conditions of the turbine and its influence on the system are studied in detail.The results obtained in the present work show that the single-stage transonic centrifugal turbine can be regarded as a potential choice to be applied in small scale ORC systems.展开更多
Purpose–The purpose of this paper is to design a unified operational design domain(ODD)monitoring framework for mitigating Safety of the Intended Functionality(SOTIF)risks triggered by vehicles exceeding ODD boundari...Purpose–The purpose of this paper is to design a unified operational design domain(ODD)monitoring framework for mitigating Safety of the Intended Functionality(SOTIF)risks triggered by vehicles exceeding ODD boundaries in complex traffic scenarios.Design/methodology/approach–A unified model of ODD monitoring is constructed,which consists of three modules:weather condition monitoring for unusual weather conditions,such as rain,snow and fog;vehicle behavior monitoring for abnormal vehicle behavior,such as traffic rule violations;and road condition monitoring for abnormal road conditions,such as road defects,unexpected obstacles and slippery roads.Additionally,the applications of the proposed unified ODD monitoring framework are demonstrated.The practicability and effectiveness of the proposed unified ODD monitoring framework for mitigating SOTIF risk are verified in the applications.Findings–First,the application of weather condition monitoring demonstrates that the autonomous vehicle can make a safe decision based on the performance degradation of Lidar on rainy days using the proposed monitoring framework.Second,the application of vehicle behavior monitoring demonstrates that the autonomous vehicle can properly adhere to traffic rules using the proposed monitoring framework.Third,the application of road condition monitoring demonstrates that the proposed unified ODD monitoring framework enables the ego vehicle to successfully monitor and avoid road defects.Originality/value–The value of this paper is that the proposed unified ODD monitoring framework establishes a new foundation for monitoring and mitigating SOTIF risks in complex traffic environments.展开更多
Background:The development of three-dimensional (3D) printing technology provides a new method for surgical treatment,but currently there are few reports on its application in the treatment of aneurysm.The aim of the ...Background:The development of three-dimensional (3D) printing technology provides a new method for surgical treatment,but currently there are few reports on its application in the treatment of aneurysm.The aim of the present study was to explore the materials and methods of fabricating 3D printed individual aneurysm model and its value in the treatment of intracranial aneurysm.Methods:Twenty-four patients with intracranial aneurysm diagnosed by CTA who had undergone operation in our hospital were analyzed retrospectively.CTA Data collected at the time of surgery was used for reconstruction.Soft Mimics 17.0 was used to reconstruct the thin layer CTA scan data into 3D image and the final data was sent to the 3D printer for fabricating the model.We compared the proposed 3D printed model-based preoperative plan and the actual approach used in the surgery based on CTA data to evaluate the value of the 3D printed model in preoperative planning,and picked out the materials which were more suitable for the clinic.Results:Twenty-four aneurysm models with high degree of reality were fabricated successfully with 3D-printing technology.The patients' blood vessels,skulls and aneurysms were printed into the reality model at a ratio of 1:1.It is reported that the soft material-based,3D printed vascular and aneurysm model more closely resembled the characteristics of the real blood vessels,thus provides a better simulation compared to the plaster-based model.Compared with the original operation plan,3D printed model could be used for pre-operative aneurysm clip selection,and provide more intuitive information in selection of operational approach.Conclusions:3D printed model can be used as an operational physical model to design operative schemes,choose the best operative paths and select suitable aneurysm clips by its high simulation degree and individualized characteristics.The model is helpful for surgical planning,especially for the preoperative plan of treating refractory multiple aneurysms and giant aneurysms.展开更多
基金partially financed by“Astro Database”Project of the University of Catania
文摘With the growing rate of automated vehicles(AVs)at the lower level of automation,the experimental tests are also in progress with vehicles at higher levels.In the absence of extended digital infrastructures and deployment of level 5 full automated vehicles,the physical infrastructure is required to maintain a fundamental role to enable their introduction in public roads.This paper focuses on lane support system(LSS)whose operational design domain(ODD)is strongly connected to the road characteristics and conditions.An experimental test was carried out with a state of the art,and LSS and advanced technologies were used for road monitoring on different roads under various environmental conditions including dry,wet pavements and rain.We applied the generalized estimation equation for logistic regression to account within-cluster homogeneity which is induced by repeated measures on the same road sections.Statistical models allow the identification of variables that are significant for the LSS fault probability among various effects of road features including marking,pavement distress,weather conditions,horizontal curvature,and cross section.Results pointed out the relevance of the wet retro-reflection of marking(RLw)and the horizontal curvature in the definition of ODD for LSS.Threshold values have been proposed for the tested LSS.Wet pavement doesn’t affect the LSS performance when compared to the dry condition.Rain was shown to be critical even with very good road characteristics.
基金supported by National Natural Science Foundation of China (No.51905116)Basic and Applied Basic Research Foundation of Guangdong Province (Item No.2020A1515111141)+3 种基金The 13th Five-Year Plan Youth Project of Philosophy and Social Science of Guangdong Province (GD20YYS03)Science and Technology Program of Guangzhou (No.201904010463)Youth Innovative Talent Projects from Ordinary University of Guangdong Province (2019WQNCX099)Innovation Training Program for College Students in Guangdong Province (S202111078058).
文摘Ergonomic reliability plays a significant role in the safe operation of devices.With the spread of infectious diseases around the world,in work environments with high loads and high infection rates,medical staff work in a state of high self-protection.The use of visual display terminal(VDT)for medical equipment has undergone fundamental changes,and the traditional medical equipment human-machine interface design needs to be improved.After the completion of design and development,a VDT design enters the experimental testing stage,which has significant limitations for simulating the work of medical staff in the high-load and high-infection environments.The testing cost is high,and subjects face harsh conditions;thus,an ergonomic reliability model that can predict the use of VDT in such special high-infection and high-load circumstances must be established.An ergonomic reliability model based on an improved backpropagation neural network(BPNN)and human cognition reliability(HCR)is proposed for predicting and evaluating operation flows according tomedical equipment VDTs.Firstly,a small data sample can be used to train BPNN to generate a network that can ensure suitable accuracy.To prevent the model from falling into local optimal solutions,the bat algorithm is introduced to improve the BPNN.Compared to a traditional BPNN,the superiority of the improved BPNN is clearly demonstrated.Secondly,the HCR method is used to analyze and highlight changes in the human factor reliability of VDTs for medical equipment in different time processes and operating processes according to BPNN prediction results,to provide a reference for selecting the optimalmethod.Finally,the validity and availability of the proposedmethod are verified through an eye tracker experiment and statistical analysis results.
文摘On March 31, in accordance with the typical design requirements of the State Grid, the f irst large electric vehicle (EV) charging station, built by the North China Grid,
文摘The desulfuration system in the second phase project of Sanhe Power Plant is the first such system that adopts in-duct FGD with no-bypass design by domestic power plants.Different from that of the conventional FGD with bypass design,a running control mode,which is important for the security of the absorbing tower within the designed ranges,shall be made to ensure the flue gas temperature and dust concentration at the inlet of the absorbing tower.The stable running of the system shows that the control mode is feasible.
文摘IPv6 is the foundation of the development of Next Generation Internet (NGI). An IPv6 network management and operations support system is necessary for real operable NGI. Presently there are no approved standards yet and relevant equipment interfaces are not perfect. A Network Management System (NMS) at the network layer helps implement the integrated management of a network with equipment from multiple vendors, including the network resources and topology, end-to-end network performance, network failures and customer Service Level Agreement (SLA) management. Though the NMS will finally realize pure IPv6 network management, it must be accommodated to the management of relevant IPv4 equipment. Therefore, modularized and layered structure is adopted for the NMS in order to implement its smooth transition.
基金supported by National Natural Science Foundation of China (Grant No. 51536006)supported by Shanghai Science and Technology Committee with Grant No.17060502300
文摘The recovery of low temperature heat sources is a hot topic in the world.The ORC system can effectively use the low temperature heat source.As its main output device,the performance of the turbine is very important.The single stage transonic turbine has the characteristics of small size and large output power.In this paper,the complete design process of a transonic centrifugal turbine with R245fa in low working temperature condition is introduced.At the design conditions,the shaft power and the wheel efficiency of the centrifugal turbine can reach 1.12 MW and 83.61%,respectively.In addition,a thermodynamic ORC cycle is presented and the off-design conditions of the turbine and its influence on the system are studied in detail.The results obtained in the present work show that the single-stage transonic centrifugal turbine can be regarded as a potential choice to be applied in small scale ORC systems.
基金the financial support of the National Key R&D Program of China(Grant No.2020YFB1600303)the National Science Foundation of China Project:(Grant Nos.U1964203 and 52072215).
文摘Purpose–The purpose of this paper is to design a unified operational design domain(ODD)monitoring framework for mitigating Safety of the Intended Functionality(SOTIF)risks triggered by vehicles exceeding ODD boundaries in complex traffic scenarios.Design/methodology/approach–A unified model of ODD monitoring is constructed,which consists of three modules:weather condition monitoring for unusual weather conditions,such as rain,snow and fog;vehicle behavior monitoring for abnormal vehicle behavior,such as traffic rule violations;and road condition monitoring for abnormal road conditions,such as road defects,unexpected obstacles and slippery roads.Additionally,the applications of the proposed unified ODD monitoring framework are demonstrated.The practicability and effectiveness of the proposed unified ODD monitoring framework for mitigating SOTIF risk are verified in the applications.Findings–First,the application of weather condition monitoring demonstrates that the autonomous vehicle can make a safe decision based on the performance degradation of Lidar on rainy days using the proposed monitoring framework.Second,the application of vehicle behavior monitoring demonstrates that the autonomous vehicle can properly adhere to traffic rules using the proposed monitoring framework.Third,the application of road condition monitoring demonstrates that the proposed unified ODD monitoring framework enables the ego vehicle to successfully monitor and avoid road defects.Originality/value–The value of this paper is that the proposed unified ODD monitoring framework establishes a new foundation for monitoring and mitigating SOTIF risks in complex traffic environments.
文摘Background:The development of three-dimensional (3D) printing technology provides a new method for surgical treatment,but currently there are few reports on its application in the treatment of aneurysm.The aim of the present study was to explore the materials and methods of fabricating 3D printed individual aneurysm model and its value in the treatment of intracranial aneurysm.Methods:Twenty-four patients with intracranial aneurysm diagnosed by CTA who had undergone operation in our hospital were analyzed retrospectively.CTA Data collected at the time of surgery was used for reconstruction.Soft Mimics 17.0 was used to reconstruct the thin layer CTA scan data into 3D image and the final data was sent to the 3D printer for fabricating the model.We compared the proposed 3D printed model-based preoperative plan and the actual approach used in the surgery based on CTA data to evaluate the value of the 3D printed model in preoperative planning,and picked out the materials which were more suitable for the clinic.Results:Twenty-four aneurysm models with high degree of reality were fabricated successfully with 3D-printing technology.The patients' blood vessels,skulls and aneurysms were printed into the reality model at a ratio of 1:1.It is reported that the soft material-based,3D printed vascular and aneurysm model more closely resembled the characteristics of the real blood vessels,thus provides a better simulation compared to the plaster-based model.Compared with the original operation plan,3D printed model could be used for pre-operative aneurysm clip selection,and provide more intuitive information in selection of operational approach.Conclusions:3D printed model can be used as an operational physical model to design operative schemes,choose the best operative paths and select suitable aneurysm clips by its high simulation degree and individualized characteristics.The model is helpful for surgical planning,especially for the preoperative plan of treating refractory multiple aneurysms and giant aneurysms.