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81.
Sandra Sendra Emilio Granell Jaime Lloret Joel J. P. C. Rodrigues 《Mobile Networks and Applications》2014,19(3):287-302
Official statistics data show that in many countries the population is aging. In addition, there are several illnesses and disabilities that also affect a small sector of the population. In recent years, researchers and medical foundations are working in order to develop systems based on new technologies and enhance the quality of life of them. One of the cheapest ways is to take advantage of the features provided by the smartphones. Nowadays, the development of reduced size smartphones, but with high processing capacity, has increased dramatically. We can take profit of the sensors placed in smartphones in order to monitor disabled and elderly people. In this paper, we propose a smart collaborative system based on the sensors embedded in mobile devices, which permit us to monitor the status of a person based on what is happening in the environment, but comparing and taking decisions based on what is happening to its neighbors. The proposed protocol for the mobile ad hoc network and the smart system algorithm are described in detail. We provide some measurements showing the decisions taken for several common cases and we also show the performance of our proposal when there is a medium size group of disabled or elderly people. Our proposal can also be applied to take care of children in several situations. 相似文献
82.
The paper connects two of the concerns of this special issue: the way to transcend the ‘bipolar tendency’ of the market culture and to ‘deal with the swings between prophesies of doom that serve only to paralyse us further, and the unbridled consumerism that makes things worse’, and how to remain human when being mediated by technology in contrast to how we are in the presence of others. Our contribution is based on an extensive conception of human beings (HBs). HBs cannot be considered only as cognitive subjects but also in their anthropological integrity. What we mean by this that they think and feel, they share concepts and emotions, they plan and desire. It implies that any attempt at reducing this complexity is a way to diminish human beings and their capabilities. HBs need meaningful course of actions to manage complexity and to tackle alternatives. Meanings come from purposeful activities, and people’s purposes are based not only on utilitarian or rational enquiries but also on what they consider right and good, according to their vision of the world. This is also the key to overcome the ‘bipolar tendency’. 相似文献
83.
The extensive use of composites in aerospace, chemical, marine, and structural applications leads to exposure to humidity and water immersion. Hence, there is a need to study the effect of moisture absorption on the mechanical properties of composite materials, especially the matrix dominated properties, such as the interlaminar shear strength (ILSS). The horizontal shear test with a short‐beam specimen in three‐point‐bending is used as a general method of evaluation for the shear properties in fiber‐reinforced composites because of its simplicity. In this work, the ILSS of cross‐ply glass‐epoxy resin composites is determined in seven different fiber directions with short‐beam three‐point‐bending tests, before and after moisture conditioning. It is found that moisture absorption reduces ILSS and stiffness of the examined composites whereas it leads to larger failure deflections. It is also found that the direction of fibers strongly affects the load–deflection response and the ILSS of the dry and conditioned specimens. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
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We analyze the classical asset pricing model assuming non fully rationalagents.Agents forecast future prices cum dividend through an adaptive learning rule.This assumption provides an explanation of some anomalies encounteredin the empirical analysis of asset prices under full rationality:returns are serially correlated(positively over a short horizon and negatively over a longer horizon)and the dividend yield predicts future returns (positive correlation).Considering the continuous time limit process,the same regularities are established analytically for price increments. 相似文献
86.
Alan M. Allgeier Denise Andersen Michael D. Bartberger Emilio E. Bunel Robert D. Larsen Pingli Liu Thomas Storz Jason S. Tedrow 《Topics in Catalysis》2014,57(17-20):1335-1341
To overcome stability issues associated with the use of an aldehyde in a catalytic reductive amination reaction, a cyclic ketolactol (ω-hydroxylactone) was employed as an aldehyde surrogate to form a γ-aminoacid. The reaction proceeded most favorably over a Pt/C catalyst. The thermodynamics of each step were evaluated using density functional theory calculations, which correctly predicted the dominance of the ring-closed lactol reactant, yet suggested a preference for a ring-opened iminium intermediate upon the initial, slightly endoergic addition of amine substrate. Exoergic hydrogenation of this intermediate provided the thermodynamic driving force for the overall transformation. During development, the reaction was observed to depend significantly on the volumetric gas to liquid mass transfer coefficient (kLa) and this parameter was optimized to ensure successful scale up in a 400 L stirred tank reactor. 相似文献
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Marengo E Manfredi M Zerbinati O Robotti E Mazzucco E Gosetti F Bearman G France F Shor P 《Analytical chemistry》2011,83(17):6609-6618
The aim of this project is the development of a noninvasive technique based on LED multispectral imaging (MSI) for monitoring the conservation state of the Dead Sea Scrolls (DSS) collection. It is well-known that changes in the parchment reflectance drive the transition of the scrolls from legible to illegible. Capitalizing on this fact, we will use spectral imaging to detect changes in the reflectance before they become visible to the human eye. The technique uses multivariate analysis and statistical process control theory. The present study was carried out on a "sample" parchment of calfskin. The monitoring of the surface of a commercial modern parchment aged consecutively for 2 h and 6 h at 80 °C and 50% relative humidity (ASTM) was performed at the Imaging Lab of the Library of Congress (Washington, DC, U.S.A.). MSI is here carried out in the vis-NIR range limited to 1 μm, with a number of bands of 13 and bandwidths that range from about 10 nm in UV to 40 nm in IR. Results showed that we could detect and locate changing pixels, on the basis of reflectance changes, after only a few "hours" of aging. 相似文献