The International Maritime Organization (IMO) has encouraged its member countries to introduce Formal Safety Assessment (FSA) for ship operations since the end of the last century. FSA can be used through certain form...The International Maritime Organization (IMO) has encouraged its member countries to introduce Formal Safety Assessment (FSA) for ship operations since the end of the last century. FSA can be used through certain formal assessing steps to generate effective recommendations and cautions to control marine risks and improve the safety of ships. On the basis of the brief introduction of FSA, this paper describes the ideas of applying FSA to the prevention of human error in ship operations. It especially discusses the investigation and analysis of the information and data using navigation simulators and puts forward some suggestions for the introduction and development of the FSA research work for safer ship operations.展开更多
Objective To study the effect of using improved 2D computer-assisted fluoroscopic navigation through simulating 3D vertebrae image to guide pedicle screw internal fixation.Methods Posterior pedicle screw internal fixa...Objective To study the effect of using improved 2D computer-assisted fluoroscopic navigation through simulating 3D vertebrae image to guide pedicle screw internal fixation.Methods Posterior pedicle screw internal fixation,distraction展开更多
A technique for testing space object receivers using global navigation satellite system (GNSS) signal simulator of the navigation field is proposed. Its structure consists of two blocks which allow synthesizing the ...A technique for testing space object receivers using global navigation satellite system (GNSS) signal simulator of the navigation field is proposed. Its structure consists of two blocks which allow synthesizing the scenario of reciprocal displacement of the receiver relative to navigation satellites and their signals. In the first block, according to the known coordinates of the receiver which are specified in tabular form or analytically, the distances between the receiver and the navigation satellites are calculated as well as their relative velocities. According to these data, the second block synthesizes the signals of navigational travelers with the specified characteristics which are transmitted via the air or cable with a given attenuation to the receiver. This allows testing on the earth receivers for airplanes and space objects under different scenarios of their movement, which not only reduces the risk of problems during the flight, but also avoids significant economic costs. Based on real data obtained by approaching two spacecraft using a simulator, the receiver was tested, which shows the promise of the proposed technology.展开更多
Navigation is the only way to develop and utilize marine resources,while the promotion of seafarers1 quality is the basic force of navigation,so navigation simulator plays an important role in modern navigation educat...Navigation is the only way to develop and utilize marine resources,while the promotion of seafarers1 quality is the basic force of navigation,so navigation simulator plays an important role in modern navigation education.The simulation research on the operation of the union purchase is important to improve the special operation training of the actual cargo handling of the union purchase.On the basis of the Cartesian coordinate system transformation algorithm,the algorithm model of the union purchase operation is constructed.On the basis of three-dimensional(3D)rendering engine technology of open scene graph(OSG),the algorithm model of finding the space coordinates of the cargo point is established.The model of catenary equation is used to optimize the scene appearance of the cargo wire.By combination of QT channel signal mechanism and OSG,the simulation interaction of the union purchase operating system is realized.By acquiring the 3D coordinate values of each point,we fit the trajectories of each point in the operation and compare the trajectories.The results show that the model has high interactivity and small error.The comparison of the states of the cargo wire before and after optimization shows that the optimized wire is more realistic and the high fidelity meets the needs of operational training and simulation systems.展开更多
文摘The International Maritime Organization (IMO) has encouraged its member countries to introduce Formal Safety Assessment (FSA) for ship operations since the end of the last century. FSA can be used through certain formal assessing steps to generate effective recommendations and cautions to control marine risks and improve the safety of ships. On the basis of the brief introduction of FSA, this paper describes the ideas of applying FSA to the prevention of human error in ship operations. It especially discusses the investigation and analysis of the information and data using navigation simulators and puts forward some suggestions for the introduction and development of the FSA research work for safer ship operations.
文摘Objective To study the effect of using improved 2D computer-assisted fluoroscopic navigation through simulating 3D vertebrae image to guide pedicle screw internal fixation.Methods Posterior pedicle screw internal fixation,distraction
文摘A technique for testing space object receivers using global navigation satellite system (GNSS) signal simulator of the navigation field is proposed. Its structure consists of two blocks which allow synthesizing the scenario of reciprocal displacement of the receiver relative to navigation satellites and their signals. In the first block, according to the known coordinates of the receiver which are specified in tabular form or analytically, the distances between the receiver and the navigation satellites are calculated as well as their relative velocities. According to these data, the second block synthesizes the signals of navigational travelers with the specified characteristics which are transmitted via the air or cable with a given attenuation to the receiver. This allows testing on the earth receivers for airplanes and space objects under different scenarios of their movement, which not only reduces the risk of problems during the flight, but also avoids significant economic costs. Based on real data obtained by approaching two spacecraft using a simulator, the receiver was tested, which shows the promise of the proposed technology.
基金the National Natural Science Foundation of China(No.51579114)the Natural Science Foundation of Fujian Province(No.2018J01485)the Project of Young and Middle-Aged Teacher Education of Fujian Province(No.JAT170309)。
文摘Navigation is the only way to develop and utilize marine resources,while the promotion of seafarers1 quality is the basic force of navigation,so navigation simulator plays an important role in modern navigation education.The simulation research on the operation of the union purchase is important to improve the special operation training of the actual cargo handling of the union purchase.On the basis of the Cartesian coordinate system transformation algorithm,the algorithm model of the union purchase operation is constructed.On the basis of three-dimensional(3D)rendering engine technology of open scene graph(OSG),the algorithm model of finding the space coordinates of the cargo point is established.The model of catenary equation is used to optimize the scene appearance of the cargo wire.By combination of QT channel signal mechanism and OSG,the simulation interaction of the union purchase operating system is realized.By acquiring the 3D coordinate values of each point,we fit the trajectories of each point in the operation and compare the trajectories.The results show that the model has high interactivity and small error.The comparison of the states of the cargo wire before and after optimization shows that the optimized wire is more realistic and the high fidelity meets the needs of operational training and simulation systems.