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851.
随着中国乃至全世界的人口老龄化问题的加剧,考虑老年人的需求变得越来越重要。通过文献调研,用户访谈和专家焦点小组的方法调查了影响老年人接受并使用信息科技的因素,共找到4个方面的16个因素,对老年人如何开始使用一种新的信息科技有了比较深刻和全面的了解。研究结果可以作为设计老年人信息科技接受问卷的依据,也可为信息科技产品的开发者设计合适的信息科技产品提供参考。 相似文献
852.
Claudio O. Gualerzi Attilio Fabbretti Letizia Brandi Pohl Milon Cynthia L. Pon 《Israel journal of chemistry》2010,50(1):80-94
Translation initiation is a complex, multi-step process of fundamental importance in all kingdoms of life, during which the start site of the genetic message transmitted in the form of an RNA molecule (mRNA) is selected, and the level of translation determined. Being the slowest step of protein synthesis, initiation is the phase most often subject to regulation. Here we review, in a historical perspective and focusing mainly on results from our laboratory, the development of our perception of the mechanisms by which the most relevant steps of this pathway occur in bacteria. In particular, we describe: (a) the mechanistics and kinetics of translation initiation; (b) properties of mRNAs with and without Shine–Dalgarno sequence relevant for initiation site selection and translational efficiency; c) ribosomal binding and dissociation of the initiation factors, formation and properties of translation initiation intermediates; (d) the mechanisms by which translation initiation fidelity is ensured. Finally, we provide a short survey of the known translation initiation inhibitors. 相似文献
853.
对中型中密度纤维板生产中造成环境污染的污染源、污染因子进行了分析研究,根据同类企业实际运行情况提出了治理途径和解决措施。 相似文献
854.
Roman Lenner 《Structure and Infrastructure Engineering》2017,13(11):1425-1436
The procedures for reliability verification of new or existing buildings are calibrated to account for uncertainties and variability of resistance and load parameters. However, present standards often provide a single approach to specification of design values of all imposed loads on buildings without particular distinction between loads associated with considerable uncertainties and well-defined loads. While the former are represented by common loads in office and residential buildings, the latter, including loads due to storage of materials, material handling equipment, machinery or tanks, require different approaches for estimating design values. This contribution identifies the characteristics of well-defined imposed loads and proposes a methodology for calibrating partial factors. Key steps of the methodology consist of assessing static load effect, dynamic amplification if relevant, model uncertainty, sensitivity factors and target reliability. Careful consideration of these influences then yields partial factors that reflect reduced uncertainties in estimating the effects of well-defined imposed loads. It appears that the commonly accepted partial factor of 1.5 in Eurocodes may be reduced. When multiple crossings are considered, the partial factor can be taken independent of the number of crossings while the characteristic value is adjusted. Further studies should be particularly focused on advanced probabilistic modelling of dynamic amplification and of model uncertainties. 相似文献
855.
Two studies are reported in which the effect of glassware was investigated on subjective ratings of, and willingness-to-pay for, alcoholic drinks. Participants from China (Study 1) and the USA (Study 2) viewed online photographs of red wine, white wine, beer, whisky, and Chinese baijiu presented in 6 different glasses, including a narrow, wide, or stemless wine glass, a highball or rocks glass, and a beer mug. They rated liking, familiarity, and congruency (between the drink and the glassware), as well as how much they would be willing to pay for the drinks. Both the type of drink and the type of glassware influenced participants’ subjective ratings of, and willingness-to-pay for, the drinks. The red and white wine were liked more, and people were willing to pay significantly more for if they thought that the glassware was congruent with the contents. These findings highlight the influence of content–context congruency on consumers’ subjective ratings and willingness-to-pay. 相似文献
856.
Overview of Human Factors and Ergonomics in the OR,with an Emphasis on Minimally Invasive Surgeries
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Operating rooms (OR) are where medical teams work to improve the health of a patient. However, because of the complexity of the procedures, errors and unsafe situations are likely to occur. These complications can lead to harm to the patient or medical professionals. Human factors and ergonomic professionals have been working to improve these unsafe conditions in the OR for over a century. However, with advances in technology, increased surgical complexity, as well as an increase in medical team members in the OR, there are still numerous improvements yet to be accomplished. Minimally invasive surgeries require an even more advanced approach to prevent errors due to technology, fatigue, and miscommunication. Human factors and ergonomic techniques provide the ability to greatly improve conditions for patients and surgeons alike. It is imperative that human factors and ergonomics continue to grow and facilitate technological advancements in healthcare. © 2012 Wiley Periodicals, Inc. 相似文献
857.
从情感化的角度研究产品的硬件控制界面,通过分析与归纳,对产品硬件控制界面上影响用户情感的各种因素进行深入的探讨。 相似文献
858.
Frédéric Perrier Patrick Richon Jean-Christophe Sabroux 《The Science of the total environment》2009,407(7):2361-2371
Radon concentration has been monitored from 1995 to 1999 in the soil of the Sur-Frêtes ridge (French Alps), covered with snow from November to April. Measurements were performed at 70 cm depth, with a sampling time of 1 h, at two points: the summit of the ridge, at an altitude of 1792 m, and the bottom of the ridge, at an altitude of 1590 m. On the summit, radon concentration shows a moderate seasonal variation, with a high value from October to April (winter), and a low value from May to September (summer). At the bottom of the ridge, a large and opposite seasonal variation is observed, with a low value in winter and a high value in summer. Fluctuations of the radon concentration seem to be associated with temperature variations, an effect which is largely delusory. Indeed, these variations are actually due to water infiltration. A simplified mixing model is used to show that, at the summit of the ridge, two effects compete in the radon response: a slow infiltration response, rich in radon, with a typical time scale of days, and a fast infiltration of radon-poor rainwater. At the bottom of the ridge, similarly, two groundwater contributions compete: one slow infiltration response, similar to the response seen at the summit, and an additional slower response, with a typical time scale of about a month. This second slower response can be interpreted as the aquifer discharge in response to snow melt. This study shows that, while caution is necessary to properly interpret the various effects, the temporal variations of the radon concentration in soil can be understood reasonably well, and appear to be a sensitive tool to study the subtle interplay of near surface transfer processes of groundwater with different transit times. 相似文献
859.
Multitasking across generations: Multitasking choices and difficulty ratings in three generations of Americans 总被引:1,自引:0,他引:1
L. Mark Carrier Nancy A. Cheever Larry D. Rosen Sandra Benitez Jennifer Chang 《Computers in human behavior》2009
This study investigated whether changes in the technological/social environment in the United States over time have resulted in concomitant changes in the multitasking skills of younger generations. One thousand, three hundred and nineteen Americans from three generations were queried to determine their at-home multitasking behaviors. An anonymous online questionnaire asked respondents to indicate which everyday and technology-based tasks they choose to combine for multitasking and to indicate how difficult it is to multitask when combining the tasks. Combining tasks occurred frequently, especially while listening to music or eating. Members of the “Net Generation” reported more multitasking than members of “Generation X,” who reported more multitasking than members of the “Baby Boomer” generation. The choices of which tasks to combine for multitasking were highly correlated across generations, as were difficulty ratings of specific multitasking combinations. The results are consistent with a greater amount of general multitasking resources in younger generations, but similar mental limitations in the types of tasks that can be multitasked. 相似文献
860.
在瓦斯地质的研究中,对瓦斯突出相关因素的分析日趋完善,怎样掌握各相关因素对突出的制约性,已经是预测煤与瓦斯突出的重点。本文试图从此论点入手,寻求预防突出事故发生的有效方法。 相似文献