The Experts below are selected from a list of 2009883 Experts worldwide ranked by ideXlab platform
Bashar Nuseibeh - One of the best experts on this subject based on the ideXlab platform.
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Problem Analysis of traditional it security risk assessment methods an experience report from the insurance and auditing domain
Information Security Conference, 2011Co-Authors: Stefan Taubenberger, Jan Jurjens, Yijun Yu, Bashar NuseibehAbstract:Traditional information technology (IT) security risk assessment approaches are based on an Analysis of events, probabilities and impacts. In practice, security experts often find it difficult to determine IT risks reliably with precision. In this paper, we review the risk determination steps of traditional risk assessment approaches and report on our experience of using such approaches. Our experience is based on performing IT audits and IT business insurance cover assessments within a reinsurance company. The paper concludes with a summary of issues concerning traditional approaches that are related to the identification and evaluation of events, probabilities and impacts. We also conclude that there is a need to develop alternative approaches, and suggest a security requirements-based risk assessment approach without events and probabilities.
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Problem frames a case for coordination
International Conference on Coordination Models and Languages, 2004Co-Authors: Leonor Barroca, Michael Jackson, Jose Luiz Fiadeiro, Robin Laney, Bashar NuseibehAbstract:We show how principles of separation of Coordination from Computation can be used to endow the Problem Frames approach to Problem Analysis with representation schemes. These representation schemes facilitate the way evolution of requirements or of the application domain can be reflected in the decomposition structure, making it easier to change.
J W Banks - One of the best experts on this subject based on the ideXlab platform.
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a stable added mass partitioned amp algorithm for elastic solids and incompressible flow model Problem Analysis
SIAM Journal on Scientific Computing, 2019Co-Authors: Daniel A Serino, J W Banks, William D Henshaw, D W SchwendemanAbstract:An Analysis is made of a new partitioned scheme for solving fluid-structure interaction Problems involving viscous incompressible flow and compressible elastic-solids. The new scheme is stable, wit...
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a stable partitioned fsi algorithm for rigid bodies and incompressible flow part i model Problem Analysis
Journal of Computational Physics, 2017Co-Authors: J W Banks, William D Henshaw, D W Schwendeman, Qi TangAbstract:A stable partitioned algorithm is developed for fluid–structure interaction (FSI) Problems involving viscous incompressible flow and rigid bodies. This added-mass partitioned (AMP) algorithm remains stable, without sub-iterations, for light and even zero mass rigid bodies when added-mass and viscous added-damping effects are large. The scheme is based on a generalized Robin interface condition for the fluid pressure that includes terms involving the linear acceleration and angular acceleration of the rigid body. Added-mass effects are handled in the Robin condition by inclusion of a boundary integral term that depends on the pressure. Added-damping effects due to the viscous shear forces on the body are treated by inclusion of added-damping tensors that are derived through a linearization of the integrals defining the force and torque. Added-damping effects may be important at low Reynolds number, or, for example, in the case of a rotating cylinder or rotating sphere when the rotational moments of inertia are small. In this first part of a two-part series, the properties of the AMP scheme are motivated and evaluated through the development and Analysis of some model Problems. The Analysis shows when and why the traditional partitioned scheme becomes unstable due to either added-mass or added-damping effects. The Analysis also identifies the proper form of the added-damping which depends on the discrete time-step and the grid-spacing normal to the rigid body. The results of the Analysis are confirmed with numerical simulations that also demonstrate a second-order accurate implementation of the AMP scheme.
D W Schwendeman - One of the best experts on this subject based on the ideXlab platform.
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a stable added mass partitioned amp algorithm for elastic solids and incompressible flow model Problem Analysis
SIAM Journal on Scientific Computing, 2019Co-Authors: Daniel A Serino, J W Banks, William D Henshaw, D W SchwendemanAbstract:An Analysis is made of a new partitioned scheme for solving fluid-structure interaction Problems involving viscous incompressible flow and compressible elastic-solids. The new scheme is stable, wit...
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a stable partitioned fsi algorithm for rigid bodies and incompressible flow part i model Problem Analysis
Journal of Computational Physics, 2017Co-Authors: J W Banks, William D Henshaw, D W Schwendeman, Qi TangAbstract:A stable partitioned algorithm is developed for fluid–structure interaction (FSI) Problems involving viscous incompressible flow and rigid bodies. This added-mass partitioned (AMP) algorithm remains stable, without sub-iterations, for light and even zero mass rigid bodies when added-mass and viscous added-damping effects are large. The scheme is based on a generalized Robin interface condition for the fluid pressure that includes terms involving the linear acceleration and angular acceleration of the rigid body. Added-mass effects are handled in the Robin condition by inclusion of a boundary integral term that depends on the pressure. Added-damping effects due to the viscous shear forces on the body are treated by inclusion of added-damping tensors that are derived through a linearization of the integrals defining the force and torque. Added-damping effects may be important at low Reynolds number, or, for example, in the case of a rotating cylinder or rotating sphere when the rotational moments of inertia are small. In this first part of a two-part series, the properties of the AMP scheme are motivated and evaluated through the development and Analysis of some model Problems. The Analysis shows when and why the traditional partitioned scheme becomes unstable due to either added-mass or added-damping effects. The Analysis also identifies the proper form of the added-damping which depends on the discrete time-step and the grid-spacing normal to the rigid body. The results of the Analysis are confirmed with numerical simulations that also demonstrate a second-order accurate implementation of the AMP scheme.
Qi Tang - One of the best experts on this subject based on the ideXlab platform.
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a stable partitioned fsi algorithm for rigid bodies and incompressible flow part i model Problem Analysis
Journal of Computational Physics, 2017Co-Authors: J W Banks, William D Henshaw, D W Schwendeman, Qi TangAbstract:A stable partitioned algorithm is developed for fluid–structure interaction (FSI) Problems involving viscous incompressible flow and rigid bodies. This added-mass partitioned (AMP) algorithm remains stable, without sub-iterations, for light and even zero mass rigid bodies when added-mass and viscous added-damping effects are large. The scheme is based on a generalized Robin interface condition for the fluid pressure that includes terms involving the linear acceleration and angular acceleration of the rigid body. Added-mass effects are handled in the Robin condition by inclusion of a boundary integral term that depends on the pressure. Added-damping effects due to the viscous shear forces on the body are treated by inclusion of added-damping tensors that are derived through a linearization of the integrals defining the force and torque. Added-damping effects may be important at low Reynolds number, or, for example, in the case of a rotating cylinder or rotating sphere when the rotational moments of inertia are small. In this first part of a two-part series, the properties of the AMP scheme are motivated and evaluated through the development and Analysis of some model Problems. The Analysis shows when and why the traditional partitioned scheme becomes unstable due to either added-mass or added-damping effects. The Analysis also identifies the proper form of the added-damping which depends on the discrete time-step and the grid-spacing normal to the rigid body. The results of the Analysis are confirmed with numerical simulations that also demonstrate a second-order accurate implementation of the AMP scheme.
William D Henshaw - One of the best experts on this subject based on the ideXlab platform.
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a stable added mass partitioned amp algorithm for elastic solids and incompressible flow model Problem Analysis
SIAM Journal on Scientific Computing, 2019Co-Authors: Daniel A Serino, J W Banks, William D Henshaw, D W SchwendemanAbstract:An Analysis is made of a new partitioned scheme for solving fluid-structure interaction Problems involving viscous incompressible flow and compressible elastic-solids. The new scheme is stable, wit...
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a stable partitioned fsi algorithm for rigid bodies and incompressible flow part i model Problem Analysis
Journal of Computational Physics, 2017Co-Authors: J W Banks, William D Henshaw, D W Schwendeman, Qi TangAbstract:A stable partitioned algorithm is developed for fluid–structure interaction (FSI) Problems involving viscous incompressible flow and rigid bodies. This added-mass partitioned (AMP) algorithm remains stable, without sub-iterations, for light and even zero mass rigid bodies when added-mass and viscous added-damping effects are large. The scheme is based on a generalized Robin interface condition for the fluid pressure that includes terms involving the linear acceleration and angular acceleration of the rigid body. Added-mass effects are handled in the Robin condition by inclusion of a boundary integral term that depends on the pressure. Added-damping effects due to the viscous shear forces on the body are treated by inclusion of added-damping tensors that are derived through a linearization of the integrals defining the force and torque. Added-damping effects may be important at low Reynolds number, or, for example, in the case of a rotating cylinder or rotating sphere when the rotational moments of inertia are small. In this first part of a two-part series, the properties of the AMP scheme are motivated and evaluated through the development and Analysis of some model Problems. The Analysis shows when and why the traditional partitioned scheme becomes unstable due to either added-mass or added-damping effects. The Analysis also identifies the proper form of the added-damping which depends on the discrete time-step and the grid-spacing normal to the rigid body. The results of the Analysis are confirmed with numerical simulations that also demonstrate a second-order accurate implementation of the AMP scheme.
