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61.
It is widely accepted that, if technology is to be more accepted in the home, it must change to better suit this environment. A number of researchers have argued that this change will take the form of the post-PC world. Rather than use home PCs, it is predicted we will use single-function appliances, crafted for specific purposes. As currently stated, the model is flawed. It over-emphasises usability barriers to home PC adoption, and ignores the great success of multi-function devices. More seriously, the argument is based on a model of innovative technologies competing with and then superseding existing technologies. This is a simplification-often there is a process ofbalkanisation, where the market and use of devices changes, grows, shrinks and is subdivided. One potential balkanisation of the home PC market space is discussed, producing a range of PC-type devices which better fit home environments.  相似文献   
62.
本文介绍了数字版权管理技术的现状和该技术在家庭网络中的应用以及存在的问题,并设计了一种基于域的家庭网络数字版权管理系统。通过域的形式组建家庭网络,既有效保护数字内容的版权,又保证用户能够灵活、方便地使用和共享数字内容。最后对该方案进行了性能和安全性分析。  相似文献   
63.
The overall aim for the present study was to analyze the consequences for reading ability among the children of a computer supported self-regulated learning environment in grade two. By means of a quasi-experimental design in a natural setting, an experimental group (n = 39) was compared to a control group from a national sample (n = 3409) on reading comprehension. The statistical analyses showed that the experimental group achieved better on reading comprehension both as a group (p < .001) as well as girls (p < .001) and boys (p < .05) separately. The proportion of high achievers was higher, and the proportion of low achievers was lower in the experimental group. In order to explain the level of reading comprehension in the experimental group Structural Equation Modelling (SEM) was used. The main explanatory factor for reading comprehension was writing with β = .44. As a tentative conclusion it was suggested that the extended writing in combination with the self-regulated learning environment can promote reading comprehension in grade two, whereas home literacy had no impact on reading comprehension in this context.  相似文献   
64.
基于物联网的人性化智能家居系统研究   总被引:1,自引:0,他引:1  
针对智能家居系统特点及需求,建立基于物联网的人性化智能家居系统架构模型,研发中转器、壁式智能控制终端、基于Android的智能控制终端,最后搭建整个基于物联网的人性化智能家居系统,进行远程控制及现场控制测试。该系统性能稳定、性价比高、舒适安全、实用性及可操作性强,可个性化情景模式控制,易于安装、维护及扩展。  相似文献   
65.
This article presents an integrated framework for the development of home automation systems following the model-driven approach. By executing model transformations the environment allows developers to generate executable code for specific platforms. The tools presented in this work help developers to model home automation systems by means of a domain specific language which is later transformed into code for home automation specific platforms. These transformations have been defined by means of graph grammars and template engines extended with traceability capabilities. Our framework also allows the models to be reused for different applications since a catalogue of requirements is provided. This framework enables the development of home automation applications with techniques for improving the quality of both the process and the models obtained. In order to evaluate the benefits of the approach, we conducted a survey among developers that used the framework. The analysis of the outcome of this survey shows which conditions should be fulfilled in order to increase reusability.  相似文献   
66.
从燃气壁挂炉维修与维护的局限性出发,提出基于家庭网络技术的燃气壁挂炉故障监测系统。该系统保留传统燃气壁挂炉显示面板和控制主板的通讯接口,硬件上串接一个故障跟踪模块。在家庭网络下,故障跟踪模块过滤出燃气壁挂炉的实时状态信息,通过网络上传到远程服务器。远程协助维修员通过上传的实时状态信息,在线给予用户故障剔除方案。本设计实现了燃气壁挂炉的远程维修与维护,为后续的燃气壁挂炉故障诊断风险分析提供了可靠的依据。  相似文献   
67.
This article describes a multimodal command language for home robot users, and a robot system which interprets users’ messages in the language through microphones, visual and tactile sensors, and control buttons. The command language comprises a set of grammar rules, a lexicon, and nonverbal events detected in hand gestures, readings of tactile sensors attached to the robots, and buttons on the controllers in the users’ hands. Prototype humanoid systems which immediately execute commands in the language are also presented, along with preliminary experiments of faceto-face interactions and teleoperations. Subjects unfamiliar with the language were able to command humanoids and complete their tasks with brief documents at hand, given a short demonstration beforehand. The command understanding system operating on PCs responded to multimodal commands without significant delay. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008  相似文献   
68.
This study assessed the relative effects of two intelligent speed adaptation (ISA) systems (informative and actively supporting) on simulated driving performance and acceptability in a sample of inexperienced and experienced drivers. Participants drove a series of simulated drives under three conditions: no ISA (control), ISA informative and ISA actively supporting. The informative system significantly reduced speed and was particularly effective in reducing top-end speeds. Comparable reductions were not found for the actively supporting system. Differences in the effectiveness and acceptability of ISA systems were noted across experienced and inexperienced drivers. The ISA systems appeared more effective at reducing speeds for experienced drivers on some road types. Experienced drivers’ subjective satisfaction ratings of the systems also remained constant over the trial, whereas the inexperienced drivers’ ratings changed after experience. There was little evidence that drivers engaged in negative behavioral adaptation and no evidence that subjective workload levels increased with ISA use. Future directions for examining the safety benefits of ISA, particularly for inexperienced drivers, are discussed.  相似文献   
69.
In absolute terms, young drivers have three to four times as many accidents per year as older drivers; and even allowing for their relative numbers in the population, their accident involvement is about 2.5 times higher than older drivers. A sample of 3437 accident reports was considered, including 1296 in detail, from midland police forces in the UK, involving drivers aged 17-25, and covering the years 1994-1996 inclusive. Four types of accident were identified as being of particular concern due to their high frequency: 'cross-flow'-turns; rear-end shunts; loss of control on bends; and accidents in darkness. (The term 'cross-flow' is used in relation to turns to denote an intersection accident where a driver is turning across the path of oncoming traffic, i.e., left turns in the US and continental Europe, but right turns in the UK and other countries where driving on the left side of the road is the norm.) An examination of driver risk taking behaviours as revealed in police interviews gave an insight into some of the motivational factors underlying young driver behaviour. Young driver accidents of all types are found to be frequently the result of 'risk taking' factors as opposed to 'skill deficit' factors. It had previously been thought that one of the main problems that young drivers have is in the area of specific skills needed in the driving task. However, it appears that a large percentage of their accidents are purely the result of two or three failures resulting from voluntary risk taking behaviour, rather than skill deficits per se. It is shown that specific groups of young drivers can even be considered as above average in driving skills, but simultaneously have a higher accident involvement due to their voluntary decisions to take risks.  相似文献   
70.
杨氏双缝干涉实验条纹光强分布   总被引:1,自引:2,他引:1  
分析了杨氏双缝干涉光强分布,对以前的研究成果进行了分析,并指出其不妥之处,并在此基础上定性地给出了在杨氏双缝干涉中明纹中心不等亮度的原因.  相似文献   
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