The Experts below are selected from a list of 145848 Experts worldwide ranked by ideXlab platform
Bonnie E. Melharlt - One of the best experts on this subject based on the ideXlab platform.
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Software Fault Tree Analysis for a Requirements System Model
1995Co-Authors: Bonnie E. MelharltAbstract:Software that is used to control critical systems is frequently tasked to ensure the safe operation of the system under its control. This paper suggests the use of fault tree analysis with an External Interaction model as part of the software requirements specification and analysis phase for the development of such systems. After a brief review of the model, the general fault tree analysis technique is described and templates for software fault tree construction directly from the model are shown.
B.e. Malhart - One of the best experts on this subject based on the ideXlab platform.
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Software fault tree analysis for a requirements system model
Proceedings of the 1995 International Symposium and Workshop on Systems Engineering of Computer Based Systems, 1995Co-Authors: B.e. MalhartAbstract:Software that is used to control critical systems is frequently tasked to ensure the safe operation of the system under its control. The paper suggests the use of fault tree analysis with an External Interaction model as part of the software requirements specification and analysis phase for the development of such systems. After a brief review of the model, the general fault tree analysis technique is described and templates for software fault tree construction directly from the model are shown.
James H Love - One of the best experts on this subject based on the ideXlab platform.
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innovation productivity and growth in us business services a firm level analysis
Technovation, 2008Co-Authors: Mica Ariana Mansury, James H LoveAbstract:This paper examines the impact of innovation on the performance of US business service firms. We distinguish between different levels of innovation (new-to-market and new-to-firm) in our analysis, and allow explicitly for sample selection issues. Reflecting the literature, which highlights the importance of External Interaction in service innovation, we pay particular attention to the role of External innovation linkages and their effect on business performance. We find that the presence of service innovation and its extent has a consistently positive effect on growth, but no effect on productivity. There is evidence that the growth effect of innovation can be attributed, at least in part, to the External linkages maintained by innovators in the process of innovation. External linkages have an overwhelmingly positive effect on (innovator) firm performance, regardless of whether innovation is measured as a discrete or continuous variable, and regardless of the level of innovation considered.
Chenguang Yang - One of the best experts on this subject based on the ideXlab platform.
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physical human robot Interaction of a robotic exoskeleton by admittance control
IEEE Transactions on Industrial Electronics, 2018Co-Authors: Bo Huang, Mingdi Deng, Chenguang YangAbstract:In this paper, a physical human–robot Interaction approach is presented for the developed robotic exoskeleton using admittance control to deal with a human subject's intention as well as the unknown inertia masses and moments in the robotic dynamics. The human subject's intention is represented by the reference trajectory when the robotic exoskeleton is complying with the External Interaction force. Online estimation of the stiffness is employed to deal with the variable impedance property of the robotic exoskeleton. Admittance control is first presented based on the measured force in order to generate a reference trajectory in Interaction tasks. Then, adaptive control is proposed to deal with the uncertain robotic dynamics and a stability criterion can be obtained. Bounded errors are shown in the motion tracking while the robustness of the variable stiffness control is guaranteed. The experimental results indicate that the proposed control enables the human subjects to execute an admittance control task on the exoskeleton robot effectively.
Emmanuel Cottancin - One of the best experts on this subject based on the ideXlab platform.
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Surface Plasmon Resonance Damping in Spheroidal Metal Particles: Quantum Confinement, Shape, and Polarization Dependences
Journal of Physical Chemistry C, 2017Co-Authors: Jean Lerme, Christophe Bonnet, Marie-ange Lebeault, Michel Pellarin, Emmanuel CottancinAbstract:A key parameter for optimizing nanosized optical devices involving small metal particles is the spectral width of their localized surface plasmon resonances (LSPR). In the small size range the homogeneous LSPR line width is to a large extent ruled by the spatial confinement-induced broadening contribution which, within a classical description, underlies the popular phenomenological limited mean free path model. This unavoidable contribution to the LSPR line width is basically a quantum finite-size effect rooted in the finite extent of the electronic wave functions. This broadening reflects the surface-induced decay of the coherent collective plasmon excitations into particle–hole (p–h) excitations (Landau damping), the signature of which is a size-dependent fragmented LSPR band pattern which is clearly evidenced in absorption spectra computed within the time-dependent local density approximation (TDLDA). In this work we analyze the spatial confinement-induced LSPR damping contribution in the framework on an exact Hamiltonian formalism, assuming for convenience a jellium-type ionic density. In resorting to the harmonic potential theorem (HPT), a theorem stating that in the case of a harmonic External Interaction the electronic center-of-mass coordinates separate strictly from the intrinsic motions of the individual electrons, we derive a simple approximate formula allowing to (i) quantify the size dependence of the LSPR damping in spherical nanoparticles (1/R law, where R is the sphere radius) and (ii) bring to the fore the main factors ruling the confinement-induced LSPR broadening. Then the modeling is straightforwardly generalized to the case of spheroidal (prolate or oblate) metal particles. Our investigations show that the LSPR damping is expected to depend strongly on both the aspect ratio of the spheroidal particles and the polarization of the irradiating electric field, that is, on the nature—transverse or longitudinal—of the collective excitation. It is found that the magnitude of the damping is tightly related to that of the LSPR frequency which rules the number of p–h excitations degenerate with the plasmon energy. Qualitative analysis suggests that the results are quite general and probably hold for other nonspherical particle shapes. In particular, in the case of elongated particles, as rods, the enlargement of the longitudinal LSPR band by the confinement effects is predicted to be much smaller than that of the transverse LSPR band.
