The conflict detection and resolution in collaborative design is a key issue to maintain multi disciplinary design consistency. This paper proposes a new method for conflict detection and resolution based on constrain...The conflict detection and resolution in collaborative design is a key issue to maintain multi disciplinary design consistency. This paper proposes a new method for conflict detection and resolution based on constraint satisfaction technique. The representation of design constraint, the interval arithmetic of the constraint satisfaction problem CSP and the conflict resolution strategy based on constraint relaxation and adjustment are introduced. A constraint satisfaction based conflict detection and resolution tool CSCDR is then developed. It can help collaborative designers to detect and resolve the conflicts in time in the early stage of the design process so that the unnecessary design iteration and repeated negotiation are avoided and the design efficiency is then much improved. A design case illustrates the effectiveness of CSCDR.展开更多
To the issues of low efficiency of conflict resolution method in collaborative design, we proposed a method, which is conflict resolution about collaborative design based on grid services.It uses the grid services fro...To the issues of low efficiency of conflict resolution method in collaborative design, we proposed a method, which is conflict resolution about collaborative design based on grid services.It uses the grid services from the current design points, uses the method of retrospective thinking to find the conflict point by detecting, and then uses the corresponding method to resolve the conflict point according to the conflict characteristic, after that carried on the conflict detection again. If there is still the conflict, resolve the conflict point again, until the conflict no longer exists. This method combines various traditional resolution methods, makes full use of the grid idle high-performance large-scale sharing resources. With this method the collaborative design conflict resolution cost reduced and the conflict resolution efficiency was raised. And then the problem which is not handled completely was then solved, so that the conflict resolution Quality was guaranteed.展开更多
Conflict Detection and Resolution（CD＆R） is the key to ensure aviation safety based on Trajectory Prediction（TP）. Uncertainties that affect aircraft motions cause difficulty in an accurate prediction of the trajec...Conflict Detection and Resolution（CD＆R） is the key to ensure aviation safety based on Trajectory Prediction（TP）. Uncertainties that affect aircraft motions cause difficulty in an accurate prediction of the trajectory, especially in the context of four-dimensional（4D） Trajectory-Based Operation（4DTBO）, which brings the uncertainty of pilot intent. This study draws on the idea of time geography, and turns the research focus of CD＆R from TP to an analysis of the aircraft reachable space constrained by 4D waypoint constraints. The concepts of space–time reachability of aircraft and space–time potential conflict space are proposed. A novel pre-CD＆R scheme for multiple aircraft is established. A key advantage of the scheme is that the uncertainty of pilot intent is accounted for via a Space-Time Prism（STP） for aircraft. Conflict detection is performed by verifying whether the STPs of aircraft intersect or not, and conflict resolution is performed by planning a conflict-free space–time trajectory avoiding intersection. Numerical examples are presented to validate the efficiency of the proposed scheme.展开更多
The specification of authorization policies in access control models proposed so far cannot satisfy the requirements in workflow management systems(WFMSs).Furthermore,existing approaches have not provided effective co...The specification of authorization policies in access control models proposed so far cannot satisfy the requirements in workflow management systems(WFMSs).Furthermore,existing approaches have not provided effective conflict detection and resolution methods to maintain the consistency of authorization polices in WFMSs.To address these concerns,we propose the definition of authorization policies in which context constraints are considered and the complicated requirements in WFMSs can be satisfied.Based on the definition,we put forward static and dynamic conflict detection methods for authorization policies.By defining two new concepts,the precedence establishment rule and the conflict resolution policy,we provide a flexible approach to resolving conflicts.展开更多
文摘The conflict detection and resolution in collaborative design is a key issue to maintain multi disciplinary design consistency. This paper proposes a new method for conflict detection and resolution based on constraint satisfaction technique. The representation of design constraint, the interval arithmetic of the constraint satisfaction problem CSP and the conflict resolution strategy based on constraint relaxation and adjustment are introduced. A constraint satisfaction based conflict detection and resolution tool CSCDR is then developed. It can help collaborative designers to detect and resolve the conflicts in time in the early stage of the design process so that the unnecessary design iteration and repeated negotiation are avoided and the design efficiency is then much improved. A design case illustrates the effectiveness of CSCDR.
基金the National High Technology Research and Development Program of China (863 Program) (2002AA414060, 2001AA411310)the Key Science and Technology Program of Shaanxi Province (2006K05- G10)
文摘To the issues of low efficiency of conflict resolution method in collaborative design, we proposed a method, which is conflict resolution about collaborative design based on grid services.It uses the grid services from the current design points, uses the method of retrospective thinking to find the conflict point by detecting, and then uses the corresponding method to resolve the conflict point according to the conflict characteristic, after that carried on the conflict detection again. If there is still the conflict, resolve the conflict point again, until the conflict no longer exists. This method combines various traditional resolution methods, makes full use of the grid idle high-performance large-scale sharing resources. With this method the collaborative design conflict resolution cost reduced and the conflict resolution efficiency was raised. And then the problem which is not handled completely was then solved, so that the conflict resolution Quality was guaranteed.
基金financial support from the Civil Aviation Joint Funds of the National Natural Science Foundation of China (No’s.U1533203,61179069)
文摘Conflict Detection and Resolution（CD＆R） is the key to ensure aviation safety based on Trajectory Prediction（TP）. Uncertainties that affect aircraft motions cause difficulty in an accurate prediction of the trajectory, especially in the context of four-dimensional（4D） Trajectory-Based Operation（4DTBO）, which brings the uncertainty of pilot intent. This study draws on the idea of time geography, and turns the research focus of CD＆R from TP to an analysis of the aircraft reachable space constrained by 4D waypoint constraints. The concepts of space–time reachability of aircraft and space–time potential conflict space are proposed. A novel pre-CD＆R scheme for multiple aircraft is established. A key advantage of the scheme is that the uncertainty of pilot intent is accounted for via a Space-Time Prism（STP） for aircraft. Conflict detection is performed by verifying whether the STPs of aircraft intersect or not, and conflict resolution is performed by planning a conflict-free space–time trajectory avoiding intersection. Numerical examples are presented to validate the efficiency of the proposed scheme.
基金supported by the National Natural Science Foundation of China (Nos.50705084 and 60473129)the Science and Technology Plan of Zhejiang Province,China (No.2007C13018)
文摘The specification of authorization policies in access control models proposed so far cannot satisfy the requirements in workflow management systems(WFMSs).Furthermore,existing approaches have not provided effective conflict detection and resolution methods to maintain the consistency of authorization polices in WFMSs.To address these concerns,we propose the definition of authorization policies in which context constraints are considered and the complicated requirements in WFMSs can be satisfied.Based on the definition,we put forward static and dynamic conflict detection methods for authorization policies.By defining two new concepts,the precedence establishment rule and the conflict resolution policy,we provide a flexible approach to resolving conflicts.
