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Primate Locomotion: Recent Advances. Elizabeth Strasser. John Fleagle. Alfred Rosenberger. and Henry McHenry. eds. New York: Plenum Press, 1998. 482 pp.

Abstract
Even though 80% of a shopper's time in the store is spent moving from place to place, little is known about managing the pace of in-store traffic flow. Based on the store atmospherics literature, this article introduces interventions to optimize the pace of locomotion. A series of lab and field experiments demonstrates that changes in flooring affect customers' walking speed. The number, the nature, and the relative salience of progress markers along a walking path toward a physical location communicate goal progress and thus the motivation to reach a particular destination. Consistent with a goal gradient account, customers walk faster when fewer progress markers are placed along the walking path to the goal. The effect of the number of progress markers diminishes when the markers are unrelated to the goal and reverses when the markers are relatively more salient than the goal. This article contributes to the goal literature by showing how markers affect perceptions of goal progress (i.e., level vs. rate of progress) and provides concrete insights to speed up and slow down customers' walking speed in a retail environment.

Human locomotion was studied for 160 societies through the use of early travel accounts, missionaries' reports, and the ethnographic literature. As a result of the value Western society has placed on a sedentary way of life, and the consequent devaluation of movement, the common "striding gait" of humans has taken on a kind of misplaced concreteness. Humans facultatively employ a number of locomotor patterns besides the habitual bipedal gait: long‐distance running, climbing, leaping, crawling, swimming, and skiing (the latter two are not dealt with in this paper). Human locomotion, like that of animals, is an analogous rather than a univocal concept, admitting great variation, plasticity, and subtle differences in gait, style, speed, and endurance. These multiple concepts have important implications for the construction of models of the evolution of hominid bipedalism.

Background: Powered robotic exoskeletons for assistance of human locomotion are currentlyunder development for military and medical applications. The energy requirements for such devices are excessive, and this has become a major obstacle for practical applications. Legged locomotion in many animals, however, is very energy efficient. We propose that poly-articular elastic mechanisms are a major contributor to the economy of locomotion in such specialized animals. Consequently, it should be possible to design unpowered assistive devices that make effective use of similar mechanisms. Methods: A passive assistive technology is presented, based on long elastic cords attached to anexoskeleton and guided by pulleys placed at the joints. A general optimization procedure is described for finding the best geometrical arrangement of such "exotendons" for assisting a specific movement. Optimality is defined either as minimal residual joint moment or as minimal residual joint power. Four specific exotendon systems with increasing complexity are considered. Representative human gait data were used to optimize each of these four systems to achieve maximal assistance for normal walking. Results: The most complex exotendon system, with twelve pulleys per limb, was able to reduce the joint moments required for normal walking by 71% and joint power by 74%. A simpler system, with only three pulleys per limb, could reduce joint moments by 46% and joint power by 47%. Conclusion: It is concluded that unpowered passive elastic devices can substantially reduce the muscle forces and the metabolic energy needed for walking, without requiring a change in movement. When optimally designed, such devices may allow independent locomotion in patients with large deficits in muscle function.

The book inquires into Aristotle's claim that of the four kinds of change that exist, locomotion is the most fundamental and important kind. In a first step, the author shows that the arguments for the thesis of locomotion's priority play a crucial role in the argument of Physics VIII and for the understanding of Aristotle's philosophy of nature in general. The main focus of the book lies on the thorough and careful reconstruction and analysis of the arguments Aristotle presents in Physics VIII.

Book reviewed in this article:Pan troglodytes (Pongidae). Walking on All Fours. Chimpanzee. By P. LEYHAUSENPan troglodytes (Pongidae). Walking Upright. Chimpanzee. By P. LEYHAUSENHomo sapiens (Hominidae). Walking I (boy, aged 11 months). By H. F. R. PRECHTLHomo sapiens (Hominidae). Walking II (girl, aged 12 months). By H. F. R. PRECHTLPan troglodytes (Pongidae). Walking on All Fours II. Chimpanzee. By P. LEYHAUSENGorilla gorilla (Pongidae). Walking on All Fours. Gorilla. By P. LEYHAUSENSimia satyrus (Pongidae). Walking on All Fours. Orangutan. By P. LEYHAUSENHomo sapiens (Hominidae). Creeping I (boy, aged 10 months). By H. F. R. PRECHTLHomo sapiens (Hominidae). Creeping II (boy, aged 10 months). By H. F. R. PRECHTLHomo sapiens (Hominidae). Getting up into a Sitting Position (girl, aged 4 months). By H. F. R. PRECHTLHomo sapiens (Hominidae). Getting up to a Standing Position (boy, aged 11 months). By H. F. R. PRECHTL

Experienced employees are a crucial asset and intelligent resource for organizations. In this study, we examined the effect of employee work experience on employee voice behavior. We also proposed employee locomotion as a factor that would affect voice behavior jointly with their work
experience and we further proposed that work experience would interact with locomotion to influence voice behavior. Data from subordinates (n = 170) and their immediate supervisors (n = 46) were collected from employees working for companies in East China. Results of hierarchical
linear modeling revealed that (a) high locomotion was positively related to promotive voice but not to prohibitive voice; and (b) high locomotion strengthened the association between both work experience and prohibitive voice and work experience and promotive voice. The theoretical and practical
implications of these findings are discussed.

Que ce soit à des fins d'amélioration de la performance ou de réhabilitation physique, l'analyse de la condition physique et de la locomotion occupe de nos jours une importante place dans le domaine des soins santé. La récente démocratisation des microcontrôleurs et de leur suite de capteurs a permis la venue de nouvelles modalités d'évaluation de la locomotion (p. ex. l'analyse cinématique avec systèmes inertiels). Ce mémoire présente le développement d'un véhicule autonome de petite taille permettant la capture vidéo d'un participant selon un suivi adaptatif utile à des fins d'analyse du mouvement et la réalisation d'évaluation de la condition physique en dehors des milieux de laboratoires et cliniques (p. ex. Salle instrumentée, tapis roulant). Le robot, fabriqué à faibles coûts, est basé sur la plateforme Raspberry Pi. De façon à conduire une collecte en milieu écologique, celui-ci est placé sur une piste d'athlétisme intérieure sur laquelle il peut se déplacer de manière autonome dans les corridors en suivant les lignes selon un algorithme de reconnaissance visuelle et d'automatisation. L'instrumentation embarquée du véhicule permet l'évaluation du participant en mode « suivi », c'est-à-dire en suivant la cadence en conservant une distance constante et sécuritaire. Le mode meneur de train » impose quant à lui une cadence au participant. Ce mode peut aussi être utilisé à des fins d'analyse de la performance ou d'entrainement. Au cours de ce document, les modalités de conception et de fabrication seront présentées. Les méthodes de vision par ordinateur pour la conduite autonome développée pour un ordinateur à faible coût et de faible puissance seront détaillées. Les résultats d'essais effectués sur une piste d'athlétisme intérieure permettant de démontrer les performances et limitations du véhicule sont présentés. Les résultats obtenus sont discutés. Finalement, de nouvelles approches pour l'évaluation de la condition physique seront proposées. ; Whether for performance enhancement or physical rehabilitation, the analysis of fitness and locomotion occupies an important place in today's healthcare. The recent democratization of microcontrollers and their suite of sensors has allowed the emergence of new methods for evaluating locomotion (e.g., kinematic analysis with inertial systems). This dissertation presents the development of an autonomous vehicle of small size allowing the video capture of a participant according to an adaptive tracking that could be used for movement analysis and physical condition evaluations performed outside of laboratory environments and clinics (e.g., Instrumented room, treadmills). The robot, manufactured at low cost, is based on the Raspberry Pi platform. In order to conduct a video data acquisition in an ecological environment, it is placed on an indoor running track on which it can move independently in the corridors by following the lane lines according to a visual recognition and automation algorithm. The onboard instrumentation of the vehicle allows the participant to be evaluated in "follow-up" mode, that is to say by following the pace while maintaining a constant and safe distance with the assessed participant. The 'pacesetter" mode, for its part, imposes a pace on the participant. This mode can also be used for performance analysis or training purposes. Throughout this document, the design and manufacturing methods will be presented. Computer vision methods for autonomous driving developed for a low cost, low-power computer will be detailed. The results of tests carried out on an indoor running track to demonstrate the performances and limitations of the vehicle are presented. Finally, new approaches for fitness assessment will be proposed.