Results 261 to 270 of about 4,043,334 (304)

Dynamic simulation of sit to stand exercise for paraplegia

2011 IEEE International Conference on Control System, Computing and Engineering, 2011
This paper describes on developing a dynamic humanoid model of sit-to-stand (STS) movement. Visual Nastran software is used to develop a humanoid model, while the humanoid movement is controlled by MATLAB/Simulink to perform sit-to-stand activity. Two control strategies are implemented in this study, which are PID controller and fuzzy logic control ...
Norazhar Abu Bakar, Abdul Rahim Abdullah
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Dynamics of free-standing smectic-Afilms

Physical Review E, 2001
The eigenvibrations and time-dependent layer displacement-layer displacement correlation functions are analyzed in a free-standing thin smectic-A films with the help of a discrete layer model. The film motions are described using the Chebyshev polynomials of second kind, U(n)(x).
V P, Romanov, S V, Ul'yanov
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Predicting stand basal area in thined stands using a dynamical model

Forest Ecology and Management, 1999
When a forest stand is thinned, its growth characteristics change. Forest analysts who model growth are then faced with the challenge of developing models that can predict stand growth in the post-thinned period, regardless of the particular thinning regime. Using Pinus patula Schl. et Cham., data from the Nelshoogte (South Africa) thinning experiment,
Oliver Chikumbo, Iven M.Y Mareels, Brian J Turner   +2 more
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Dynamic properties of almost monochromatic standing waves

Asymptotic Analysis, 2010
For a scalar field propagating at light velocity c, we show that kinematic and dynamic properties of almost monochromatic standing waves, with frequency Ω(x, t)=ω±δΩ(x, t), where ω is constant, and δΩ(x, t) ω, are formally identical with mechanical properties of matter. They are both described by equations with the same mathematical structure.
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Dynamic control of a two-stand cold mill

Automatica, 1969
The design of a control system for a two-stand tandem cold rolling mill producing thin brass sheet is developed. The control objective is to minimize output thickness variations resulting from three process disturbances while observing a number of physical constraints. Three manipulated variables are available, and five process measurements can be made
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The dynamics of stand development: a general stand model applied to Douglas-fir

Canadian Journal of Forest Research, 1988
A linked pair of hypotheses which represent causal explanations for plant growth and stand mortality for an even-aged stand are developed. The pair of dynamic equations lead to a four-parameter Douglas-fir simulation model. The four-parameter model relates the development of stand volume and density to site quality, initial stocking density, and ...
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Stand dynamics and red spruce decline

Canadian Journal of Forest Research, 1990
The red spruce (Picearubens Sarg.) growth decline in the northeastern United States does not appear to be ubiquitous. Some selected tree-ring data sets are compared graphically and with two models that tend to support the notion that differences exist between stands as to the presence and degree of decline.
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Dynamics of stand structure in plant monocultures

Journal of Theoretical Biology, 1984
The model dynamics of stand structure in even-aged plant monocultures is proposed, where stand structure is characterized by size distributions of plant height, stem diameter and plant weight. Skewness of plant height distribution is at first zero, becomes negative, then returns to zero and maintains its value; skewness of stem diameter distribution is
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Dynamics of an Uneven-Aged Forest Stand

Forest Science, 1972
Abstract The components of net growth for number of trees and basal area are described as a system of first-order, ordinary differential equations for an uneven-aged forest stand. Data from a 6-year period are utilized to estimate coefficients for the governing equations.
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Stand and tree dynamics in uneven-aged interior Douglas-fir stands

2009
The Interior Douglas-fir Biogeoclimatic Zone covers 4 million hectares in the southern interior of British Columbia. This zone is dominated by interior Douglas-fir forests which are valued for their timber, wildlife, range and recreational values. Interior Douglas-fir can be found growing naturally in uneven-aged structured stands; a structure that ...
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