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51.
In this paper we report our early experience with the design of technology for senior citizens. We take as our point of departure a pre-study of the ways in which older adult living occurs at three different senior housing facilities in southern Sweden. We contribute to the current debate concerning the ways in which digital technology can be designed to enable new types of living arrangements for the ever growing population of older people. We focus on technology designed to support the social rather than physical challenges of growing older. In particular we discuss how designing for social interaction can circumvent the stigma associated with being lonely in light of diminishing social networks, changed patterns of interactions with family, moving to a new neighbourhood, and the loss of a spouse. We will suggest that designers, in the design of digital technology for social interaction, deliberately leave room for ambiguity to make it possible for people to leave their intentions of use unarticulated. Furthermore, recognizing that many everyday activities already act as enablers for social interaction, we suggest utilizing such activities as an approach for design. We will support our suggestions by introducing three perspectives: a perspective emphasizing that the population of older adults is one of resourceful individuals; a perspective on social interaction emphasizing its circumstantial nature as an inherent part of everyday activities; and a perspective on the role of digital technology emphasizing its role as merely one of many resources present for human action. Finally, we will present an example concept showing how an enhanced TV remote control may be designed to enable social interactions without inflicting too much on the original experience of watching TV and most importantly, without stigmatizing the people using the remote control as lonely individuals craving the company of others.  相似文献   
52.
A major disadvantage with fixed modulation (nonadaptive) on channels with varying signal-to-noise ratio (SNR) is that the bit-error-rate (BER) probability performance is changing with the channel quality. Most applications require a certain maximum BER and there is normally no reason for providing a smaller BER than required. An adaptive modulation scheme, on the contrary, can be designed to have a BER which is constant for all channel SNRs. The spectral efficiency of the fixed modulation is constant, while it, in general, will increase with increasing channel SNRs for the adaptive scheme. This in effect means that the average spectral efficiency of the adaptive scheme is improved, while at the same time the BER is better suited to the requirement of the application. Thus, the adaptive link becomes much more efficient for data transmission. The major disadvantage is that the transmitter needs to know the channel SNR such that the best suitable modulation is chosen and the receiver must be informed on the used modulation in order to decode the information. This leads to an increased overhead in the system as compared with a fixed modulation system. In this paper, we introduce adaptive modulation systems by presenting some of the simpler adaptive quadrature amplitude modulation schemes and their performance for both perfectly known and predicted channels.  相似文献   
53.
Different visualization strategies for structuring non-hierarchical learning tasks in hypermedia are used until now. Do these strategies differ in learning effectiveness? In the present study, a hypermedia learning environment about cell biology was investigated. The graphical properties of a content module were created in two different ways, either depicting close-up views of the cell organelles or with connecting lines between the cell organelles and their respective technical terms within the graphic of the whole cell. Students’ post test performance indicate that connecting lines fostered auditory recall, that is remembering and understanding of narrative information, more efficiently than close-up views. In the case of visual recall, that is identification of electron microscopic pictures depicting cell structures, there was no difference in performance between these two visualization techniques. Transfer performance depended on an interaction between visualization technique and students’ spatial ability: Only students with high spatial ability benefited from the connecting lines variant. With respect to auditory recall and transfer performance, the present study supports the structure mapping effect as proposed by the integrated model of text and picture comprehension. Especially students with low spatial ability seem to be prone to an illusion of knowing.  相似文献   
54.
Dealing with conflicting and target-specific requirements is an important issue in multisensor and multitarget tracking. This paper aims to allocate sensing resources among various targets in reaction to individual information requests. The proposed approach is to introduce agents for every relevant target responsible for its tracking. Such agents are expected to bargain with each other for a division of resources. A bilateral negotiation model is established for resource allocation in two-target tracking. The applications of agent negotiation to target covariance tuning are illustrated together with simulation results presented. Moreover, we suggest a way of organizing simultaneous one-to-one negotiations, making our negotiation model still applicable in scenarios of tracking more than two targets.  相似文献   
55.
Ag2Cu2O3 thin films were deposited on glass substrates by RF magnetron sputtering of an equiatomic silver-copper target (Ag0.5Cu0.5) in reactive Ar-O2 mixtures. The reactive sputtering was done at varying power, oxygen flow rate and deposition temperature to study the influence of these parameters on the deposition of Ag2Cu2O3 films. The film structure was determined by X-ray diffraction, while the optical properties were examined by spectrophotometry (UV-vis-NIR) and photoluminescence. Furthermore, the film thickness and resistivity were measured by tactile profilometry and 4-point probe, respectively. Additional mobility, resistivity and charge carrier density Hall effect measurements were done on a few selected samples. The best films in terms of stoichiometry and crystallography were achieved with a sputtering power of 100 W, oxygen and argon flow rates of 20 sccm (giving a deposition pressure of 1.21 Pa) and a deposition temperature of 250 °C. The optical transmittance and photoluminescence spectra of films deposited with these parameters indicate several band gaps, most prominently, a direct one of around 2.2 eV. Electrical characterization reveals charge carrier concentrations and mobilities in the range of 1021-1022 cm− 3 and 0.01-0.1 cm2/Vs, respectively.  相似文献   
56.
The aim of this paper is to incorporate a model for micro/nano lithography production processes in topology optimization. The production process turns out to provide a physical analogy for projection filters in topology optimization. Blueprints supplied by the designers cannot be directly used as inputs to lithographic processes due to the proximity effect which causes rounding of sharp corners and geometric interaction of closely spaced design elements. Therefore, topology optimization is applied as a tool for proximity effect correction. Furthermore, it is demonstrated that the robust projection filter can be used to account for uncertainties due to lithographic production processes which results in manufacturable blueprint designs and eliminates the need for subsequent corrections.  相似文献   
57.
58.
In this article, the authors study the factorial structure of 2 versions (64 items and 32 items) of the Dutch translation of the Inventory of Interpersonal Problems (IIP; L. M. Horowitz, L. E. Alden, J. S. Wiggins, & A. L. Pincus, 2000) in both a clinical sample (n = 382) and a student sample (n = 287). First, the authors test whether both inventories are constituted by correlated uni-dimensional subscales, and they conclude that this is true only for the short version. Second, the authors study whether the correlations between the subscales follow a circumplex pattern. This proves to be true for both versions. Coefficients alpha and correlations between the IIP-64 and IIP-32 subscales are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
59.
As global biodiversity declines, biodiversity and conservation have become ever more important research topics. Research in chemical ecology for conservation purposes has not adapted to address this need. During the last 10–15 years, only a few insect pheromones have been developed for biodiversity and conservation studies, including the identification and application of pheromones specifically for population monitoring. These investigations, supplemented with our knowledge from decades of studying pest insects, demonstrate that monitoring with pheromones and other semiochemicals can be applied widely for conservation of rare and threatened insects. Here, I summarize ongoing conservation research, and outline potential applications of chemical ecology and pheromone-based monitoring to studies of insect biodiversity and conservation research. Such applications include monitoring of insect population dynamics and distribution changes, including delineation of current ranges, the tracking of range expansions and contractions, and determination of their underlying causes. Sensitive and selective monitoring systems can further elucidate the importance of insect dispersal and landscape movements for conservation. Pheromone-based monitoring of indicator species will also be useful in identifying biodiversity hotspots, and in characterizing general changes in biodiversity in response to landscape, climatic, or other environmental changes.  相似文献   
60.
In recent years, a number of ferritic interconnect materials for use in solid oxide fuel cells (SOFC) have been developed and are now commercially available. Although similar, there are substantial variations in minor alloying elements. This study compares the oxidation performance of five such interconnect materials: Crofer 22 H, Crofer 22 APU (ThyssenKrupp VDM), Sanergy HT (Sandvik Materials Technology), ZMG232 G10 (Hitachi Metals) and E-Brite (ATI Allegheny Ludlum).  相似文献   
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