The objective of this paper is to mitigate the wave-induced vibration of offshore platform with magneto-rheological (MR) damper. The model of the platform coupled with MR damper is established where the external wave force is approximated with a white noise via a designed filter. Based on Linear Quadratic Gaussian (LQG) method, the optimal control force is determined when taking the measurement...

Coherent control is based on optical manipulation of the amplitudes and phases of wave functions. It is expected to be a key technique to develop novel quantum technologies such as bond-selective chemistry and quantum computing, and to better understand the quantum worldview founded on wave-particle duality. We have developed high-precision coherent control by imprinting optical amplitudes and ...

2 Abstract Role-based access control (RBAC) is a promising alternative to traditional discretionary and mandatory access controls. In RBAC permissions are associated with roles, and users are made members of appropriate roles thereby acquiring the roles' permissions. In this paper we formally show that lattice-based mandatory access controls can be enforced by appropriate connguration of RBAC c...

Since its formalization RBAC has become the yardstick for the evaluation of access control formalisms. In order to meet organizational needs, it has been extended along several directions: delegation, separation of duty, history-based access control, etc. We propose in this paper an access control language in which RBAC and all the above-listed extensions can be encoded. In contrast with Cassan...

The paper tailors the so-called wave-based control popular in the field of flexible mechanical structures to the field of distributed control of vehicular platoons. The proposed solution augments the symmetric bidirectional control algorithm with a wave-absorbing controller implemented on the leader, and/or on the rear-end vehicle. The wave-absorbing controller actively absorbs an incoming wave...

The irregular wave disturbance attenuation problem for jacket-type offshore platforms involving the nonlinear characteristics is studied. The main contribution is that a digital-control-based approximation of optimal wave disturbances attenuation controller (AOWDAC) is proposed based on iteration control theory, which consists of a feedback item of offshore state, a feedforward item of wave for...

The Role-Based Access Control (RBAC) model is traditionally used to manually assign users to appropriate roles, based on a specific enterprise policy, thereby authorizing them to use the roles' permissions. In environments where the service-providing enterprise has a huge customer base this task becomes formidable. An appealing solution is to automatically assign users to roles. The central con...

We consider the safety problem for Administrative RoleBased Access Control (ARBAC) policies, i.e. detecting whether sequences of administrative actions can result in policies by which a user can acquire permissions that may compromise some security goals. In particular, we are interested in sequences of safety problems generated by modifications (namely, adding/deleting an element to/from the s...