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81.
New developments in flexible electronics require metal films to adhere to polymer substrates. Measuring the interfacial adhesion of these systems is challenging, requiring the formulation of new techniques and models. A strategy to measure the adhesion of Cr–polyethylene terephthalate (PET) interfaces using tensile straining and buckle formation is presented in this article. Focused ion beam cross-sectioning of the buckles reveals that the polymer substrate can locally fail, which may lead to an overestimate of adhesion. Cr–PET adhesion energy of 9.4?±?1.6?J/m2 is determined with the present approach.  相似文献   
82.
There is underway a worldwide shift in society from an industrial‐based to an information‐based metaindustrial way of living and working. This will require innovative organization and management. Three factors are described as propellers of this industrial transformation: technological innovations, technology transfer, and global marketplace. Trends in post‐industrial organizations are mapped out, and a profile of metaindustrial organization culture is created.?  相似文献   
83.
The possibility that preferred modes of locomotion emerge from dynamical and optimality constraints and the energetic and dynamical constraints on preferred and predicted walking frequency are explored in this article. Participants were required to walk on a treadmill at their preferred frequency, at a frequency predicted as the resonance of a hybrid pendulum-spring model of the legs, and at frequencies ±15%, ±25%, ±35% of the predicted frequency. Walking at the preferred and predicted frequencies resulted in minimal metabolic costs and maximal stability of the head and joint actions. Mechanical energy conservation was constant across conditions. The head was more stable than the joints. The joints appeared to be in service of the head in maintaining a stable trajectory. The major findings of this study suggest a complementary relationship between energetic (physiological) and stability constraints in the adoption of a preferred frequency of walking. Multiple subsystems may be involved in constraining observed macroscopic behavior in intact biological systems. The approach and results of the study imply that a useful tack in understanding how dynamical control structures arise is to study the potential criteria that serve to act as constraints on skilled movement patterns in unimpaired and impaired populations.  相似文献   
84.
Most energy spent in walking is due to step-to-step transitions. During this phase, the interlimb coordination assumes a crucial role to meet the demands of postural and movement control. The authors review studies that have been carried out regarding the interlimb coordination during gait, as well as the basic biomechanical and neurophysiological principles of interlimb coordination. The knowledge gathered from these studies is useful for understanding step-to-step transition during gait from a motor control perspective and for interpreting walking impairments and inefficiency related to pathologies, such as stroke. This review shows that unimpaired walking is characterized by a consistent and reciprocal interlimb influence that is supported by biomechanical models, and spinal and supraspinal mechanisms. This interlimb coordination is perturbed in subjects with stroke.  相似文献   
85.
Nuclear energy has received substantial recent attention, marketed as a ‘green’ solution to global climate change (GCC) with calls for new reactors. However, considerable debate exists about whether it represents a viable solution to GCC. Given the complexity and urgency of the issue, a full and balanced debate is desirable. Since media play an important role in shaping public perception, we examined print media coverage of proposed reactors in Georgia—one site in the southeastern United States, which has been the focus of such proposals. We analysed the content of editorials and news articles from two local newspapers—the Augusta Chronicle and Atlanta Journal‐Constitution. The former exclusively published pro‐nuclear opinion pieces whereas the latter published a mix of pro‐ and anti‐nuclear opinions. The majority of news articles in both newspapers generally presented balanced arguments. Pro‐ and anti‐nuclear arguments most often reflected economic and environmental benefits and risks, whereas informational text primarily detailed regulatory processes and financing. Findings suggested that informational text was not necessarily ‘neutral’, sometimes masking covert pro‐ and anti‐nuclear content. Implications for how findings might shape public opinion and strategies for shaping media and extending public deliberation are discussed. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
86.
This article discusses Zohar’s subversive reflexive aesthetics, termed the “Archimedean-lever ethics,” comprised of three stages: the world rendered from one perspective; the same world rendered from a different perspective, challenging or destroying the first; and awareness of the shift of perspectives. It argues that Zohar’s creative energy, imbued with male sexuality, derives from this collision, and examines its ethical aspect in relation to Zionist values during the 1950s and 1960s. Zionism and Israel should always consider more than one perspective, being able not only to build but also to destroy (convictions, territories) in order to bring change, with destruction thus becoming a particular form of creation. However, in Zohar’s films made during the 1970s, the male sexual energy becomes an endless sexual appetite, expressed mostly through coveting gazes, which is no more than a cover up for male impotency, tantamount to Israel’s endless appetite for land.  相似文献   
87.
Axiomatizing Relativistic Dynamics without Conservation Postulates   总被引:1,自引:0,他引:1  
A part of relativistic dynamics is axiomatized by simple and purely geometrical axioms formulated within first-order logic. A geometrical proof of the formula connecting relativistic and rest masses of bodies is presented, leading up to a geometric explanation of Einstein’s famous E = mc 2. The connection of our geometrical axioms and the usual axioms on the conservation of mass, momentum and four-momentum is also investigated.  相似文献   
88.
Ingrid Shafer 《Zygon》2002,37(1):121-136
A philosopher-poet-theologian ponders the implications of the multimillion-year biogenetic process that produced Homo sapiens and is beginning to reveal itself ever more clearly as evolution of the mind and consciousness. As meaning trappers and makers, called to actualize the divine image imprinted upon us, we are now facing biological and cultural evolution with deliberate human input as well as the evolution of evolution. As communicating animals that are becoming ever more aware of our adaptive behavior, we have the potential of affecting our own destiny by listening to the spirit within and nurturing the genes and memes that give rise to physical, intellectual, creative, and moral excellence. In the matrix of cyberspace we have the opportunity to heal the two-culture split, to reinvent ourselves, to incubate/weave the emergent religions of the future, and to create our multiple "Ways" appropriate to the dawning Age of Global Dialogue.  相似文献   
89.
Since the nineteenth century, the problem of the arrow of time has been traditionally analyzed in terms of entropy by relating the direction past-to-future to the gradient of the entropy function of the universe. In this paper, we reject this traditional perspective and argue for a global and non-entropic approach to the problem, according to which the arrow of time can be defined in terms of the geometrical properties of spacetime. In particular, we show how the global non-entropic arrow can be transferred to the local level, where it takes the form of a non-spacelike local energy flow that provides the criterion for breaking the symmetry resulting from time-reversal invariant local laws.  相似文献   
90.
by Robert Larmer 《Zygon》2009,44(3):543-557
Many contemporary thinkers seeking to integrate theistic belief and scientific thought reject what they regard as two extremes. They disavow deism in which God is understood simply to uphold the existence of the physical universe, and they exclude any view of divine influence that suggests the performance of physical work through an immaterial cause. Deism is viewed as theologically inadequate, and acceptance of direct immaterial causation of physical events is viewed as scientifically illegitimate. This desire to avoid both deism and any positing of God as directly intervening in the physical order has led to models of divine agency that seek to defend the reality of divine causal power yet affirm the causal closure of the physical. I argue, negatively, that such models are unsuccessful in their attempts to affirm both the reality of divine causal power acting in the created world and the causal closure of the physical and, positively, that the assumption that underlies these models, namely that any genuine integration of theistic and scientific belief must posit the causal closure of the physical on pain of violating well-established conservation principles, is mistaken.  相似文献   
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