Analytical modeling and collaborative optimization of the dynamic responses for barrier-vehicle-occupant system considering crashworthiness and compatibility

The dynamic behavior of a thin-walled hollow sphere colliding onto a rigid wall has been studied by experiments, numerical simulation and analytical modeling, as reported in our previous papers. In the present paper, the impact crushing of metallic thin-walled hollow spheres onto rigid plates and the subsequent rebound are analyzed using finite element method. The effects of hollow sphere’s thickness-to-radius ratio, the material properties and the impact velocity on the dynamic responses are systematically investigated. The transition from axisymmetric dimpling to non-axisymmetric lobing is found to depend on the relative thickness of spheres and impact velocity; while the coefficient of restitution almost merely depends on impact velocity.

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Macroorganisation and flexibility of thylakoid membranes

Biochemical Journal ◽

10.1042/bcj20190080 ◽

2019 ◽

Vol 476 (20) ◽

pp. 2981-3018 ◽

Cited By ~ 8

Author(s):

Petar H. Lambrev ◽

Parveen Akhtar

Keyword(s):

Light Harvesting ◽

Current Knowledge ◽

Three Dimensional ◽

Photosynthetic Apparatus ◽

Dynamic Responses ◽

State Transitions ◽

Photochemical Quenching ◽

Light Harvesting Complex ◽

Complex Ii ◽

Light Harvesting Complex Ii

Abstract The light reactions of photosynthesis are hosted and regulated by the chloroplast thylakoid membrane (TM) — the central structural component of the photosynthetic apparatus of plants and algae. The two-dimensional and three-dimensional arrangement of the lipid–protein assemblies, aka macroorganisation, and its dynamic responses to the fluctuating physiological environment, aka flexibility, are the subject of this review. An emphasis is given on the information obtainable by spectroscopic approaches, especially circular dichroism (CD). We briefly summarise the current knowledge of the composition and three-dimensional architecture of the granal TMs in plants and the supramolecular organisation of Photosystem II and light-harvesting complex II therein. We next acquaint the non-specialist reader with the fundamentals of CD spectroscopy, recent advances such as anisotropic CD, and applications for studying the structure and macroorganisation of photosynthetic complexes and membranes. Special attention is given to the structural and functional flexibility of light-harvesting complex II in vitro as revealed by CD and fluorescence spectroscopy. We give an account of the dynamic changes in membrane macroorganisation associated with the light-adaptation of the photosynthetic apparatus and the regulation of the excitation energy flow by state transitions and non-photochemical quenching.

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2007 Motor Vehicle Occupant Safety Survey: Driver Education and Graduated Driver Licensing

PsycEXTRA Dataset ◽

10.1037/e590942009-001 ◽

2008 ◽

Cited By ~ 3

Author(s):

Alan W. Block ◽

Sharon Walker

Keyword(s):

Motor Vehicle ◽

Driver Education ◽

Occupant Safety ◽

Vehicle Occupant ◽

Graduated Driver Licensing ◽

Driver Licensing

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Classification of Acceleration Waveforms during Walking by Wavelet Transform

Methods of Information in Medicine ◽

10.1055/s-0038-1636855 ◽

1997 ◽

Vol 36 (04/05) ◽

pp. 356-359 ◽

Cited By ~ 27

Author(s):

M. Sekine ◽

M. Ogawa ◽

T. Togawa ◽

Y. Fukui ◽

T. Tamura

Keyword(s):

Wavelet Transform ◽

Wavelet Analysis ◽

Center Of Gravity ◽

Dynamic Responses ◽

Sequential Data ◽

Acceleration Signal ◽

Continuous Dynamic

Abstract:In this study we have attempted to classify the acceleration signal, while walking both at horizontal level, and upstairs and downstairs, using wavelet analysis. The acceleration signal close to the body’s center of gravity was measured while the subjects walked in a corridor and up and down a stairway. The data for four steps were analyzed and the Daubecies 3 wavelet transform was applied to the sequential data. The variables to be discriminated were the waveforms related to levels -4 and -5. The sum of the square values at each step was compared at levels -4 and -5. Downstairs walking could be discriminated from other types of walking, showing the largest value for level -5. Walking at horizontal level was compared with upstairs walking for level -4. It was possible to discriminate the continuous dynamic responses to walking by the wavelet transform.

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Control of Vibrations due to Moving Loads on Suspension Bridges

Nonlinear Analysis Modelling and Control ◽

10.15388/na.2006.11.3.14749 ◽

2006 ◽

Vol 11 (3) ◽

pp. 293-318 ◽

Cited By ~ 4

Author(s):

M. Zribi ◽

N. B. Almutairi ◽

M. Abdel-Rohman

Keyword(s):

Bridge Deck ◽

Suspension Bridge ◽

Lyapunov Theory ◽

Dynamic Responses ◽

Suspension Bridges ◽

Control Force ◽

Moving Loads ◽

Hydraulic Actuator ◽

Long Span ◽

Suspended Cables

The flexibility and low damping of the long span suspended cables in suspension bridges makes them prone to vibrations due to wind and moving loads which affect the dynamic responses of the suspended cables and the bridge deck. This paper investigates the control of vibrations of a suspension bridge due to a vertical load moving on the bridge deck with a constant speed. A vertical cable between the bridge deck and the suspended cables is used to install a hydraulic actuator able to generate an active control force on the bridge deck. Two control schemes are proposed to generate the control force needed to reduce the vertical vibrations in the suspended cables and in the bridge deck. The proposed controllers, whose design is based on Lyapunov theory, guarantee the asymptotic stability of the system. The MATLAB software is used to simulate the performance of the controlled system. The simulation results indicate that the proposed controllers work well. In addition, the performance of the system with the proposed controllers is compared to the performance of the system controlled with a velocity feedback controller.

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