The use of optimization techniques has become integral to the design and analysis of most industrial and socio-economic systems. Great strides have been made recently in the solution of large-scale problems arising in...
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ISBN:
(数字)9781475728361
ISBN:
(纸本)9780792354581;9781441948076
The use of optimization techniques has become integral to the design and analysis of most industrial and socio-economic systems. Great strides have been made recently in the solution of large-scale problems arising in such areas as production planning, airline scheduling, government regulation, and engineering design, to name a few. Analysts have found, however, that standard mathematical programming models are often inadequate in these situations because more than a single objective function and a single decision maker are involved. Multiple objective programming deals with the extension of optimization techniques to account for several objective functions, while game theory deals with the inter-personal dynamics surrounding conflict. Bilevel programming, the focus of this book, is in a narrow sense the combination of the two. It addresses the problern in which two decision makers, each with their individual objectives, act and react in a noncooperative, sequential manner. The actions of one affect the choices and payoffs available to the other but neither player can completely dominate the other in the traditional sense.
Dynamic walking on bipedal robots has evolved from an idea in science fiction to a practical reality. This is due to continued progress in three key areas: a mathematical understanding of locomotion, the computational...
Dynamic walking on bipedal robots has evolved from an idea in science fiction to a practical reality. This is due to continued progress in three key areas: a mathematical understanding of locomotion, the computational ability to encode this mathematics through optimization, and the hardware capable of realizing this understanding in practice. In this context, this review outlines the end-to-end process of methods that have proven effective in the literature for achieving dynamic walking on bipedal robots. We begin by introducing mathematical models of locomotion, from reduced-order models that capture essential walking behaviors to hybrid dynamical systems that encode the full-order continuous dynamics along with discrete foot-strike dynamics. These models form the basis for gait generation via (nonlinear) optimization problems. Finally, models and their generated gaits merge in the context of real-time control, wherein walking behaviors are translated to hardware. The concepts presented are illustrated throughout in simulation, and experimental instantiations on multiple walking platforms are highlighted to demonstrate the ability to realize dynamic walking on bipedal robots that is both agile and efficient.
作者：
HANSEN, O. RICHARDUHLER, DALE G.O. Richard Hansen obtained a BSCE from Colorado State University in 1950 and has participated in continuing educational courses at the University of Washington
Wayne State University and the University of Michigan. He was employed at Puget Sound Naval Shipyard for five years as a Mechanical Engineer and Project leader in industrial gases and cryogenic O2. Producers for Shipboard Applications followed by seven years at Chrysler Corporation initially as a project engineer in the FBM program subsequently assigned to Mechanical Laboratory achieving Managing Engineer status of a department therein which contained the facilities group instrumentation group and an experimental machine shop. This was followed by employment at Westinghouse Astronuclear Laboratories as a senior engineer conducting studies in two phase liquid hydrogen flow in simulated NERVA cores. Following this he served two years of employment with the Lockheed Georgia Company conducting material studies in combined nuclear cryogenic environments at the NASA 60 megawatt test reactor located in Sandusky Ohio. Joined NAVSEC in 1966 as a mechanical engineer in the compressed air systems group and has been assigned to the Supervisor of Diving Salvage and Ocean Engineering conducting analysis and evaluation of compressed air and gas systems associated with diving and salvage operations. Dale G. Uhler received BSCE degree from Carnegie Institute of Technology in 1964. He spent two years as a construction engineer before entering graduate school at the University of Miami
Florida where he received his MS degree in applied mechanics with a minor in Ocean Engineering in 1968. He is now employed as an Ocean Engineer in the office of the U. S. Navy Director of Diving Salvage and Ocean Engineering where he is the project manager for the Large Object Salvage System and related development programs and concurrently working toward his Ph. D. at Catholic University.
The advent of deep ocean technology has created a need of buoyancy at ever increasing depths. This paper concerns itself with two most widely used techniques for dewatering/deballasting, compressed air supplied by sur...
Mathematical models of the human left ventricle are presented to determine the physiological response-oriented mechanical parameters of the LV, which have diagnostic significance. These parameters are (i) the rheologi...
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Mathematical models of the human left ventricle are presented to determine the physiological response-oriented mechanical parameters of the LV, which have diagnostic significance. These parameters are (i) the rheological parameters of the left ventricular muscle, namely the instantaneous values of stiffness of series elasticity, parallel elasticity, and the stress-strain rate relationship for the contractile unit that characterizes the deviatric stress-strain response of a left ventricular muscle element, (ii) the effective modulus of the LV, and (iii) the state of stress in the LV. The rheological parameters are obtained from a continuum model of the LV whose stress state equilibrates the chamber pressure and whose strain state equals the instantaneous strains in the actual LV, obtained from instantaneous changes in the geometry of the LV (as noted from cineangiocardiography); the constitutive equations for the model incorporate the known existing rheological models for the isolated cardiac muscle. The effective moduli of the LV are obtained by correlating the fundamental frequency of vibration of a spherical model of the LV with the corresponding frequencies of the second component of the first heart sound and the third heart sound; thus the values of representative moduli (and hence indices of the left ventricular stiffnesses) at systole and diastole are obtained. The stress state in the LV is obtained by utilizing single plane cineangiocardiographic information of the irregular geometry of the LV in anteroposterior projection. Plane stress finite element analysis of this planor irregular geometry of the LV is done and the resulting stresses are reduced by a factor, heuristically determined to make allowance for the actual 3-dimensional geometry of the LV; the stresses obtained thus bring out effects of irregular boundary of varying (and at times high) curvature.
This book gathers papers presented at the 9th International Conference of Movement, Health and Exercise (MoHE 2023) held at Kota Kinabalu, Sabah, Malaysia. The content covers the following topics: exercise science; hu...
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ISBN:
(数字)9789819741861
ISBN:
(纸本)9789819741854;9789819783243
This book gathers papers presented at the 9th International Conference of Movement, Health and Exercise (MoHE 2023) held at Kota Kinabalu, Sabah, Malaysia. The content covers the following topics: exercise science; human performance; physical activity & health; sports medicine; sports nutrition; management & sports studies; and sports engineering & technology. The articles published will be of interest to researchers and practitioners from the field of rehabilitation, exercise medicine and sports technology.
Solid tumors are characterized by a remodeled and stiffened extracellular matrix. The extracellular matrix is not a passive by-product of the tumor, but actively compromises tissue-specific differentiation, enhances t...
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Solid tumors are characterized by a remodeled and stiffened extracellular matrix. The extracellular matrix is not a passive by-product of the tumor, but actively compromises tissue-specific differentiation, enhances tumor cell proliferation and survival, and fosters tumor cell invasion and migration. The tumor extracellular matrix also influences the behavior of the stromal cells, which through vicious, feedforward-reinforcing pathways promote tumor progression and compromise treatment efficacy. To investigate how the tumor extracellular matrix alters cancer phenotype and treatment, a number of three-dimensional, organotypic culture models have been developed that employ a variety of materials, including natural matrices, collagen, fibrin, and reconstituted basement membrane gels, as well as synthetic hydrogel materials such as polyacrylamide and polyethylene glycol. These models have been used to interrogate how specific microenvironmental features modify tumor and stromal cell function and to identify the molecular mechanisms that regulate tumorigenesis and therapeutic efficacy. To translate these findings into more effective treatment strategies for patients, clinically informed studies are needed that incorporate computational modeling and in vivo validation.
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