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1.
In the past, thinking of carrying electronic devices inside our bodies was only posed by non-real scenarios. The emergence of insertable devices has changed this. Since this technology is still in its initial development stages, few studies have investigated factors that influence its acceptance. This paper analyzes the predictors of the intention to use non-medical insertable devices in two Latin American contexts. We used partial least squares structural equation modeling to examine whether six constructs predicted intention to use insertable devices. A questionnaire was administered to undergraduate students located in Colombia and Chile (n = 672). We also examined whether these predictors influenced intention differently for both of them. Four common constructs significantly and positively influenced both Chilean and Colombian respondents to use insertable devices (hedonic motivation, habit, performance expectancy, and social influence). Also, the habit has a complementary mediating effect on the relationship between social influence and behavioral intention. By contrast, effort expectations were a positive and significant predictor, but only among Chilean respondents. Findings suggest that when technologies are emerging, well-known predictors of intention (e.g., performance and effort expectations) are less influential than predictors related to self-efficacy (e.g., habit and hedonic motivation). The use of insertable devices has a significant impact on society. Thus, a better understanding of what motivates their use has implications for both academia and industry. 相似文献
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老人的健康与建筑室内环境存在重要联系,为了给适老建筑的暖通系统优化设计提供理论依据,有必要探究室内空气调节设备与老人健康的关系。对广州市104位本地老年人进行了问卷调查,收集了老年人的基本健康信息和家庭使用空气调节设备的情况,包括制冷、除湿、采暖和空气净化4种设备及其使用时长,使用习惯。收集到的信息用SPSS20.0进行了统计分析。结果包括广州市老年人家中四种设备拥有率、设备平均使用龄、设备使用时间以及常见日均使用时长;所调查的老年人健康比例达到55.8%。患病老人中心血管疾病的比例最高,其余为风湿性疾病和关节炎等疾病。相关性分析表明,广州地区夏天家庭采取制冷措施的老人患病可能性更小;制冷设备常见日均使用时长与身处空调区域时长的比值越大,老人患病的可能性越小。 相似文献
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This paper illustrates whether the availability of online content of local interest affects the likelihood of individuals to connect to the internet and spend more time online. While the literature demonstrates a number of factors which push or enable individuals to spend more time online, we know little about the conditions that pull or attract individuals online. Although we know that individuals use the internet to access information, we do not know whether such attraction forces are relevant at the local scale too. Gaining a better understanding of how such mechanisms work at the local scale can assist our efforts to bridge digital divides, which tend to be geographically clustered. To explore this we utilise innovative data, which contain all the archived webpages under the UK top level domain name (.uk) and we calculate the volume of internet content of local interest at the neighbourhood level using the geolocation information included in the text of these webpages. Specifically, we calculate the radius of gyration for every archived website using the different postcodes included in the archived webpages and then we create an aggregated measure at the neighbourhood level discounting websites that have less of a local focus. We merge this measure of Local Internet Content (LIC) with a large population survey, which contains information about the frequency of internet usage in the UK and estimate the effect of LIC on the likelihood of an individual being a frequent internet user. Multilevel models are employed to utilise both individual and geographical level characteristics. Our results indicate that even after controlling for the individual and geographical characteristics, which according to previous studies affect internet usage, the availability of internet content of local interest still attracts individuals online. 相似文献
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高能同步辐射光源(HEPS)具有0.1 nm·rad的超低发射度,对束流稳定度提出了较高要求,研制1台高性能快校正磁铁电源用来提高快速轨道反馈系统(FOFB)的性能以提升束流稳定度。电源样机采用新颖的多电平级联拓扑结构提升电源样机的动态性能,使用基于数字控制的新颖控制方法实现样机的动态性能提升。软件仿真与样机试验数据证明,电源样机具有10 kHz小信号带宽、电源阶跃响应时间小于70 μs、输出电流纹波低于20 ppm,电源样机可很好地满足HEPS建设需求。 相似文献
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Fair bandwidth allocation (FBA) has been studied in optical burst switching (OBS) networks, with the main idea being to map the max-min fairness in traditional IP networks to the fair-loss probability in OBS networks. This approach has proven to be fair in terms of the bandwidth allocation for differential connections, but the use of the ErlangB formula to calculate the theoretical loss probability has made this approach applicable only to Poisson flows. Furthermore, it is necessary to have a reasonable fairness measure to evaluate FBA models. This article proposes an approach involving throughput-based-FBA, called TFBA, and recommends a new fairness measure that is based on the ratio of the actual throughput to the allocated bandwidth. An analytical model for the performance of the output link with TFBA is also proposed. 相似文献
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Vivian Hsueh Hua Chen Claudia Wilhelm Sven Joeckel 《Behaviour & Information Technology》2020,39(9):957-969
ABSTRACT The time displacement hypothesis has been widely used to explain the effects of media use on academic performance. This approach has been criticised for its monocausality and weak explanatory power. Utilising a combination of different theoretical perspectives is better suited than utilising only one. Considering displacement, excitement, attraction and third variable hypothesis, this paper argues that the relation between video game use and school performance is not the same for all types of gamers by considering the influence of socioeconomic, psychological and contextual factors. It investigates how gaming patterns (frequency, time of day) and psychological characteristics (sensation seeking, aggression) are related to academic performance for primary and secondary school students. Five hundred and seven students from five primary and four secondary schools in Singapore participated in a paper-pencil survey. Results showed support for a combination of displacement and third variable hypothesis, as overall time spent on video games was negatively associated with primary school children’s and active gamers’ school performances. There was no significant relationship for secondary school children. For primary school children who play games in the morning and afternoon, video game use was negatively associated with school performance. There was no support for the attraction and excitement hypotheses. 相似文献
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针对超级计算机系统中网络引导时间开销大的问题,提出网络引导分布算法是影响网络引导性能的主要因素之一,是优化网络引导性能的主要方向的观点。首先,分析了影响大规模网络引导性能的主要因素;其次,结合一种典型超级计算机系统,分析了超节点循环分布算法(SCDA)和插件循环分布算法(BCDA)的网络引导数据流拓扑结构;最后,量化分析了这两种算法对各个网络路径段的压力和可获得的网络性能,发现BCDA性能是SCDA性能的1~20倍。通过理论分析和模型推导发现,在计算节点和引导服务器之间使用更细粒度的映射算法可以在引导部分资源时使用尽量多的引导服务器,减少对局部网络资源的过早竞争,提升网络引导性能。 相似文献
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When a fast-steering mirror (FSM) system is designed, satisfying the performance requirements before fabrication and assembly is vital. This study proposes a structural parameter design approach for an FSM system based on the quantitative analysis of the required closed-loop bandwidth. First, the open-loop transfer function of the FSM system is derived. In accordance with the transfer function, the notch filter and proportional-integral (PI) feedback controller are designed as a closed-loop controller. The gains of the PI controller are determined by maximizing the closed-loop bandwidth while ensuring the robustness of the system. Then, the two unknown variables of rotational radius and stiffness in the open-loop transfer function are optimized, considering the bandwidth as a constraint condition. Finally, the structural parameters of the stage are determined on the basis of the optimized results of rotational radius and stiffness. Simulations are conducted to verify the theoretical analysis. A prototype of the FSM system is fabricated, and corresponding experimental tests are conducted. Experimental results indicate that the bandwidth of the proposed FSM system is 117.6 Hz, which satisfies the minimum bandwidth requirement of 100 Hz. 相似文献
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