<span style="font-family:Verdana;">Hydroplaning phenomenon is one of the major factors that must be considered to ensure safe driving on wet road surfaces. In this paper, the approach to numerical simu...<span style="font-family:Verdana;">Hydroplaning phenomenon is one of the major factors that must be considered to ensure safe driving on wet road surfaces. In this paper, the approach to numerical simulation of the physical hydroplaning characteristics using patterned tire is described. A detailed 3-D patterned tire model is constructed by in-house modeling program and the water flow is considered as incompressible. The complex tire material compositions are effectively modeled using composites, and rubber properties generalize the Mooney-Rivlin model. The finite element method (FEM) and the advanced finite volume method (FVM) are used for structural and for fluid-tire interaction analysis, respectively. Performance prediction of hydroplaning via coupling of computational fluid dynamics (CFD) and FEM has delivered a detailed insight into the local mechanisms and root causes of hydroplaning. Numerical examples were verified by comparing the experimental test results and it is confirmed to indicate similar correlation tendency and high reliability. The effect of driving velocity, pattern groove size, and pattern direction on hydroplaning phenomenon of tire is discussed and logical results were obtained.</span>展开更多
Rice is a crucial food crop globally.Soil salt stress has adverse effects on the physiology and biochemistry of rice,leading to ionic toxicity and disrupted metabolism.Research aimed at improving salt tolerance and un...Rice is a crucial food crop globally.Soil salt stress has adverse effects on the physiology and biochemistry of rice,leading to ionic toxicity and disrupted metabolism.Research aimed at improving salt tolerance and understanding its underlying mechanisms in rice is becoming increasingly important.Phytohormones are crucial in managing rice’s reaction to salt stress by controlling its physiological and biochemical functions.Some phytohormones can improve salt tolerance in rice by affecting gene programming,protein expression,and salt stress signaling,thereby helping rice adapt to salt-stressed environments.This review highlights recent advancements in understanding how various phytohormones-such as abscisic acid(ABA),auxin(IAA),cytokinins(CKs),jasmonates(JA),gibberellins(GAs),melatonin(MT),salicylic acid(SA),ethylene(ETHY)and brassinosteroids(BRs)-help mitigate the detrimental effects of salt stress in rice.Additionally,we explore the current challenges and future research directions for utilizing exogenous phytohormone regulators to boost rice’s resistance to salt stress.展开更多
Objectives:We systematically reviewed the rational use of medicines using the World Health Organization/International Network of Rational Use of Drugs(WHO/INRUD)core drug use indicators.We also assessed the impact of ...Objectives:We systematically reviewed the rational use of medicines using the World Health Organization/International Network of Rational Use of Drugs(WHO/INRUD)core drug use indicators.We also assessed the impact of the coronavirus disease 2019 pandemic and the National Drug Policy(NDP)2005 on the rational use of medicines.Methods:Searches were conducted in PubMed,Scopus,and Google Scholar databases to identify studies that met our eligibility criteria.Assessment of the quality of studies was conducted using the Joanna Briggs Institute criteria for analytical studies.We reported and compared the median values of WHO/INRUD core drug use indicators with standard thresholds.Data were presented with median,interquartile range(IQR),and percentages.MannWhitney and Kruskal-Wallis tests were conducted to assess for statistical significance(P<0.05)across variables.Results:Thirty-one studies were included in the review,comprising 50,931 patient encounters across 268 health facilities.Within prescribing indicators,average number of medicines per patient encountered[3.4(IQR:3.0to 4.0)],percentage of medicines prescribed by generic[50.4%(IQR:47.4%to 65.0%)],percentage of encounters with antibiotic prescribed[40.2%(IQR:30.5%to 52.7%)],percentage of encounters with injection prescribed[18%(IQR:3.2%to 30.0%)]and the percentage of medicines prescribed from essential medicines list[82.0%(IQR:66.4%to 89.3%)].The median percentage of encounters with antibiotics(P=0.04)and the median percentage of medicines prescribed by generics(P=0.03)increased during and after the COVID-19 pandemic.Prescribing indicators were worse in primary and secondary health facilities,with significant differences in the median percentage of encounters with antibiotics(P=0.007)and injections(P=0.0002)across primary,secondary,and tertiary health facilities.There were improvements across all prescribing indicators after the implementation of NDP 2005.Conclusions:Core drug use indicators in Nigerian health facilities deviated from the WHO/INRUD thresholds,with noticeable improvement after the implementation of NDP 2005.More efforts are needed to improve rational drug use in Nigerian hospitals.展开更多
New approaches for testing of autonomous driving functions are using Virtual Reality (VR) to analyze the behavior of automated vehicles in various scenarios. The real time simulation of the environment sensors is stil...New approaches for testing of autonomous driving functions are using Virtual Reality (VR) to analyze the behavior of automated vehicles in various scenarios. The real time simulation of the environment sensors is still a challenge. In this paper, the conception, development and validation of an automotive radar raw data sensor model is shown. For the implementation, the Unreal VR engine developed by Epic Games is used. The model consists of a sending antenna, a propagation and a receiving antenna model. The microwave field propagation is simulated by a raytracing approach. It uses the method of shooting and bouncing rays to cover the field. A diffused scattering model is implemented to simulate the influence of rough structures on the reflection of rays. To parameterize the model, simple reflectors are used. The validation is done by a comparison of the measured radar patterns of pedestrians and cyclists with simulated values. The outcome is that the developed model shows valid results, even if it still has deficits in the context of performance. It shows that the bouncing of diffuse scattered field can only be done once. This produces inadequacies in some scenarios. In summary, the paper shows a high potential for real time simulation of radar sensors by using ray tracing in a virtual reality.展开更多
Recently, virtual realities and simulations play important roles in the development of automated driving functionalities. By an appropriate abstraction, they help to design, investigate and communicate real traffic sc...Recently, virtual realities and simulations play important roles in the development of automated driving functionalities. By an appropriate abstraction, they help to design, investigate and communicate real traffic scenario complexity. Especially, for edge cases investigations of interactions between vulnerable road users (VRU) and highly automated driving functions, valid virtual models are essential for the quality of results. The aim of this study is to measure, process and integrate real human movement behaviour into a virtual test environment for highly automated vehicle functionalities. The overall system consists of a georeferenced virtual city model and a vehicle dynamics model, including probabilistic sensor descriptions. By motion capture hardware, real humanoid behaviour is applied to a virtual human avatar in the test environment. Through retargeting methods, which enable the independency of avatar and person under test (PuT) dimensions, the virtual avatar diversity is increased. To verify the biomechanical behaviour of the virtual avatars, a qualitative study is performed, which funds on a representative movement sequence. The results confirm the functionality of the used methodology and enable PuT independence control of the virtual avatars in real-time.展开更多
文摘<span style="font-family:Verdana;">Hydroplaning phenomenon is one of the major factors that must be considered to ensure safe driving on wet road surfaces. In this paper, the approach to numerical simulation of the physical hydroplaning characteristics using patterned tire is described. A detailed 3-D patterned tire model is constructed by in-house modeling program and the water flow is considered as incompressible. The complex tire material compositions are effectively modeled using composites, and rubber properties generalize the Mooney-Rivlin model. The finite element method (FEM) and the advanced finite volume method (FVM) are used for structural and for fluid-tire interaction analysis, respectively. Performance prediction of hydroplaning via coupling of computational fluid dynamics (CFD) and FEM has delivered a detailed insight into the local mechanisms and root causes of hydroplaning. Numerical examples were verified by comparing the experimental test results and it is confirmed to indicate similar correlation tendency and high reliability. The effect of driving velocity, pattern groove size, and pattern direction on hydroplaning phenomenon of tire is discussed and logical results were obtained.</span>
基金supported by the Basic Research Fund of Weifang Institute of Science and Technology under Grant No.KJRC2023047.
文摘Rice is a crucial food crop globally.Soil salt stress has adverse effects on the physiology and biochemistry of rice,leading to ionic toxicity and disrupted metabolism.Research aimed at improving salt tolerance and understanding its underlying mechanisms in rice is becoming increasingly important.Phytohormones are crucial in managing rice’s reaction to salt stress by controlling its physiological and biochemical functions.Some phytohormones can improve salt tolerance in rice by affecting gene programming,protein expression,and salt stress signaling,thereby helping rice adapt to salt-stressed environments.This review highlights recent advancements in understanding how various phytohormones-such as abscisic acid(ABA),auxin(IAA),cytokinins(CKs),jasmonates(JA),gibberellins(GAs),melatonin(MT),salicylic acid(SA),ethylene(ETHY)and brassinosteroids(BRs)-help mitigate the detrimental effects of salt stress in rice.Additionally,we explore the current challenges and future research directions for utilizing exogenous phytohormone regulators to boost rice’s resistance to salt stress.
文摘Objectives:We systematically reviewed the rational use of medicines using the World Health Organization/International Network of Rational Use of Drugs(WHO/INRUD)core drug use indicators.We also assessed the impact of the coronavirus disease 2019 pandemic and the National Drug Policy(NDP)2005 on the rational use of medicines.Methods:Searches were conducted in PubMed,Scopus,and Google Scholar databases to identify studies that met our eligibility criteria.Assessment of the quality of studies was conducted using the Joanna Briggs Institute criteria for analytical studies.We reported and compared the median values of WHO/INRUD core drug use indicators with standard thresholds.Data were presented with median,interquartile range(IQR),and percentages.MannWhitney and Kruskal-Wallis tests were conducted to assess for statistical significance(P<0.05)across variables.Results:Thirty-one studies were included in the review,comprising 50,931 patient encounters across 268 health facilities.Within prescribing indicators,average number of medicines per patient encountered[3.4(IQR:3.0to 4.0)],percentage of medicines prescribed by generic[50.4%(IQR:47.4%to 65.0%)],percentage of encounters with antibiotic prescribed[40.2%(IQR:30.5%to 52.7%)],percentage of encounters with injection prescribed[18%(IQR:3.2%to 30.0%)]and the percentage of medicines prescribed from essential medicines list[82.0%(IQR:66.4%to 89.3%)].The median percentage of encounters with antibiotics(P=0.04)and the median percentage of medicines prescribed by generics(P=0.03)increased during and after the COVID-19 pandemic.Prescribing indicators were worse in primary and secondary health facilities,with significant differences in the median percentage of encounters with antibiotics(P=0.007)and injections(P=0.0002)across primary,secondary,and tertiary health facilities.There were improvements across all prescribing indicators after the implementation of NDP 2005.Conclusions:Core drug use indicators in Nigerian health facilities deviated from the WHO/INRUD thresholds,with noticeable improvement after the implementation of NDP 2005.More efforts are needed to improve rational drug use in Nigerian hospitals.
文摘New approaches for testing of autonomous driving functions are using Virtual Reality (VR) to analyze the behavior of automated vehicles in various scenarios. The real time simulation of the environment sensors is still a challenge. In this paper, the conception, development and validation of an automotive radar raw data sensor model is shown. For the implementation, the Unreal VR engine developed by Epic Games is used. The model consists of a sending antenna, a propagation and a receiving antenna model. The microwave field propagation is simulated by a raytracing approach. It uses the method of shooting and bouncing rays to cover the field. A diffused scattering model is implemented to simulate the influence of rough structures on the reflection of rays. To parameterize the model, simple reflectors are used. The validation is done by a comparison of the measured radar patterns of pedestrians and cyclists with simulated values. The outcome is that the developed model shows valid results, even if it still has deficits in the context of performance. It shows that the bouncing of diffuse scattered field can only be done once. This produces inadequacies in some scenarios. In summary, the paper shows a high potential for real time simulation of radar sensors by using ray tracing in a virtual reality.
文摘Recently, virtual realities and simulations play important roles in the development of automated driving functionalities. By an appropriate abstraction, they help to design, investigate and communicate real traffic scenario complexity. Especially, for edge cases investigations of interactions between vulnerable road users (VRU) and highly automated driving functions, valid virtual models are essential for the quality of results. The aim of this study is to measure, process and integrate real human movement behaviour into a virtual test environment for highly automated vehicle functionalities. The overall system consists of a georeferenced virtual city model and a vehicle dynamics model, including probabilistic sensor descriptions. By motion capture hardware, real humanoid behaviour is applied to a virtual human avatar in the test environment. Through retargeting methods, which enable the independency of avatar and person under test (PuT) dimensions, the virtual avatar diversity is increased. To verify the biomechanical behaviour of the virtual avatars, a qualitative study is performed, which funds on a representative movement sequence. The results confirm the functionality of the used methodology and enable PuT independence control of the virtual avatars in real-time.
