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101.
Research on elderly people's ICT acceptance and use often relies on the technology acceptance model (TAM) framework, but has been mostly limited to task-oriented uses. This article expands approaches in technology acceptance and use by developing a model to explain entertainment-related uses of new media technology by elderly people. On a theoretical level, we expand the TAM perspective by adding concepts that act as barriers and/or facilitators of technology acceptance, namely technophobia, self-efficacy and previous experience and expertise with technology. We develop an expanded TAM by testing the role of these concepts in two studies on entertainment media technology. In Study 1, we investigate behavioural intention to use 3D cinema among N?=?125 German elderly media users (Age 50+). In Study 2, we focus the actual use of a computer game simulation by N?=?115 German and US elderly media users (Age 50+). Findings in both studies point towards the central role of perceived usefulness, here modelled as enjoyment, as the reason for elderly people's use and acceptance of entertainment media technology. Perceived ease of use is seen as a precondition for enjoyment, particularly for interactive media.  相似文献   
102.
The specifics of business intelligence systems compared to operational IS motivate the necessity to research the business intelligence systems acceptance determinants separately. The authors followed an exploratory approach in order to conceptualize a business intelligence acceptance model. Their findings show that in the Business Intelligence Systems context, there is a significant emphasis on organizational factors, such as result demonstrability, social influence, and facilitating conditions with sufficient resources that help build an adequate information culture all substantially influencing the effective acceptance of business intelligence systems.  相似文献   
103.
Abstract

Without prior searching instruction, undergraduate novices wrote structured self-reports during their first session on a Web search engine. Users chose their own topics and followed written instructions that prompted them to describe thoughts and feelings during specified stages of the search: pre-search formulation; search statement formulation; search strategy; and evaluation of results. The sentences in the self-reports were numbered and then coded according to their affective or cognitive function. The affective sentences reveal how users set goals and limit the scope of the cognitive operations. Search acts appear to be governed by an affective filter that organizes incoming information and provides criteria for ranking cognitive relevance to search goal. The cognitive sentences reveal a variety of operations in executing searches. Following the search, students made self-ratings on self-confidence as searchers and satisfaction with the search experience, with explanations of their ratings. Content analysis identified reasons users have for rating self-confidence, stress level, satisfaction, usefulness, and success with future searches.  相似文献   
104.
在综合分析区域水资源特点、水资源承载能力、用水水平与效率及产业结构调整和水价等影响因素的基础上,提出了工业、农业和生活等方面的节水潜力.以提高水资源利用效率和效益为核心,根据我国不同地区的自然特点、水资源条件、经济社会发展和生态环境保护及其对水资源高效利用的要求,研究提出全国节水型社会建设的目标与任务,确定了不同区域用水效率控制红线,制定了全国节水战略与布局,提出了工业、农业和城镇生活等重点领域节水对策措施.按照量水而行、以水定发展的原则,因地制宜确定不同区域节水型社会建设的重点和方向.  相似文献   
105.
叶发勇 《红水河》2011,(6):123-125,129
岷江航电犍为枢纽工程建设征地涉及的耕(园)地数量较大,移民生产安置人口较多,安置任务繁重,安置压力大.在遵守国家和四川省有关政策、法规及规范的前提下,根据建设征地区的实际情况、移民环境容量分析成果并结合地方政府的意见和移民安置意愿,拟定了采取农业安置与自谋职业、养老保障安置相结合的生产安置方案.  相似文献   
106.
The high speed fluid jet for directly or indirectly breaking rock is one of the most effective ways to improve the deep penetration rate.In order to maximize the efficiency of energy use,the flow characteristics of different combinations of high pressure jet nozzles are analyzed through numerical simulations.According to the velocity vectors at the bottom and the bottom hole pressure diagram,the effects of the high pressure nozzle combinations on the flow structure and the penetration rate are analyzed.It is shown that the combination of three vertical edge nozzles is very efficient,but inefficient in cleaning the bottom hole and eroding the wall.The jet velocity is 400 m/s and the radius is 5 mm,with a center nozzle added,the problem can be solved,but the high-pressure fluid displacement would increase.The center nozzle’s jet velocity is 200 m/s and the radius is 8 mm,the combination of two vertical edge nozzles and a center tilt nozzle or that of a vertical edge nozzle and a center tilt nozzle would provide a flow structure favorable for drilling.The angle of inclination is 10o.To take advantage of high pressure jet energy to improve the efficiency of drilling,it is important to select a suitable nozzle combination according real conditions.  相似文献   
107.
东江流域基于水质的水资源有偿使用与生态补偿机制   总被引:1,自引:0,他引:1  
回顾了东江流域生态补偿的政策与实践,认为基于发展机会损失下的生态补偿机制有悖于我国水资源国家所有的基本国情,是导致东江流域生态补偿进展缓慢的根本原因。提出建立基于水资源有偿使用的生态补偿机制:通过"使用者向国家付费,国家向保护者转移",实现对水源保护区的生态补偿。  相似文献   
108.
作战模拟系统中陆军指挥员模型建模十分重要,其决策不确定性强,功能实现复杂。针对这一问题,提出了基于认知主导决策模型的建模思想,并针对其计算机实现面临的决策者经验态势结构化描述、经验态势与当前态势自动匹配以及指挥员行为建模等重点难点问题提出了解决策略。  相似文献   
109.
The Sanaga River is one of Sub‐Saharan Africa's largest and greatly regulated rivers. Available flow data for this hydrosystem largely cover the pre‐ and post‐regulation periods. From comparisons between unregulated (hypothetical) and observed scenarios, it has been possible to separate and to quantify hydro‐climatic (groundwater + rainfall) change effects from anthropogenic impacts (especially dam‐related alterations). To appreciate shifts in the river regime, discontinuity detection tests and the IHA model were applied to discharge data series reflecting average and extreme flow conditions, respectively. Results obtained principally from the Hubert segmentation method reveal that a major discontinuity occurred in 1970–1971 separating a surplus phase between 1945–1946 and 1969–1970, and a deficient and much contrasted one, from 1971/1972. This implies that the Sanaga catchment is dominantly affected by hydro‐climatic changes. However, wide land cover/land use changes experienced here since 1988 have resulted in an increase in surface runoff. Additional quickflows linked to these changes may have partly compensated for the substantial decline in the dry season rainfall and groundwater inputs observed from this date. Although at the monthly scale, dam‐related impacts on average flows increase with stage of regulation, the seasonal variability of the river regime remains generally unaffected. A comparison of the IHA statistics, calculated from unregulated and observed streamflow data, show that hydrologic shifts occurring in maximum and minimum discharges are mostly significant from 1971/1972 and are mainly due to the action of dams. Minimum flows appear, however, widely impacted, thus reflecting the prime objective assigned to the existing reservoirs, constructed to supplement flows for hydroelectricity production during the dry season. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
110.
摘要:随着信息和信息技术的发展,信息工程技术越发的发挥着重要作用,信息工程技术以越来越高的频率出现在我们眼前,信息工程技术的应用越来越得到人们的重视。本文介绍了信息工程技术,介绍了信息工程技术建设办公自动化和违法建筑违法用地监测的意义和方法。  相似文献   
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