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1.
睡眠期间连续且准确的呼吸量监测有助于推断用户的睡眠阶段以及提供一些慢性疾病的线索。现有工作主要针对呼吸频率进行感知和监测,缺乏对呼吸量进行连续监测的手段。针对上述问题提出了一种基于商用无线射频识别(RFID)标签的无线感知用户睡眠期间呼吸量的系统——RF-SLEEP。RF-SLEEP通过阅读器连续收集附着在胸部表面的标签阵列返回的相位值及时间戳数据,计算出呼吸引起的胸部不同点的位移量,基于广义回归神经网络(GRNN)构建胸部不同点的位移量与呼吸量之间的关系模型,从而实现对用户睡眠期间呼吸量的评估。RF-SLEEP通过在用户肩膀处附着双参考标签,消除用户睡眠期间翻转身体对胸部位移计算造成的误差。实验结果表明,RFSLEEP对不同用户睡眠期间的呼吸量连续监测的平均精确度为92.49%。  相似文献   
2.
Quality of Life (QoL) is decreased in multiple sclerosis (MS), but studies about the impact of sleep disorders (SD) on health-related quality of Life (HRQoL) are lacking. From our original cohort, a cross-sectional polysomnographic (PSG) study in consecutive MS patients, we retrospectively analysed the previously unpublished data of the Nottingham Health Profile (NHP). Those MS patients suffering from sleep disorders (n = 49) showed significantly lower HRQoL compared to MS patients without sleep disorders (n = 17). Subsequently, we classified the patients into four subgroups: insomnia (n = 17), restless-legs syndrome, periodic limb movement disorder and SD due to leg pain (n = 24), obstructive sleep apnea (n = 8) and patients without sleep disorder (n = 17). OSA and insomnia patients showed significantly higher NHP values and decreased HRQoL not only for the sleep subscale but also for the “energy” and “emotional” area of the NHP. In addition, OSA patients also showed increased NHP values in the “physical abilities” area. Interestingly, we did not find a correlation between the objective PSG parameters and the subjective sleep items of the NHP. However, this study demonstrates that sleep disorders can reduce HRQoL in MS patients and should be considered as an important confounder in all studies investigating HRQoL in MS.  相似文献   
3.
Reviews the book, L'insomnie: Traitement comportemental by Robert Ladouceur and Yves Gros-Louis (1984). The work offers a prospect broader than the medical vision which traditionally dominates the treatment of insomnia. More specifically, the work is articulated around two chapters. The first locates the relative source data of insomnia, and provides the criteria for a precise diagnosis, establishing a clear distinction between primary insomnia and secondary insomnia, and methods generally utilized to measure sleep. As for the second chapter, it is centered on the behavioral methods of treatment of insomnia. According to the authors, any treatment must be preceded by factual information on insomnia, to facilitate the application of the chosen method. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
4.
This study examined the moderating effects of temperamental resistance to control on the link between development of sleep problems and development of externalizing behaviors over a 5-year period. Resistance to control was assessed with mothers' retrospective reports of temperament in infancy, provided when children were 5 years of age. Sleep problems were assessed with mother reports on an annual basis from age 5 to age 9. Externalizing behaviors were assessed with teacher reports on an annual basis from age 5 to age 9. A cross-domain latent growth curve model indicated that sleep problem trajectories were positively associated with externalizing behavior trajectories only for children high in resistance to control. In addition, resistance to control was positively associated with initial (age 5) sleep problems and initial (age 5) externalizing behaviors. The authors speculate that the development of sleep problems promotes the development of behavior problems for resistant children, whose self-regulatory abilities are especially tenuous. Implications for prevention and treatment of conduct problems are considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
5.
The literature contains inconsistent data on the effects of acute sleep deprivation on the superior cognitive functions. The primary purpose of this study is to determine the effectiveness of inhibition, one of the functions of the working memory executive centre (EC), over an extended, 36-hour waking period. Inhibition is a cognitive mechanism whereby individuals ignore non-relevant information recorded in their working memory. We also tested the effects of a 36- hour period of acute sleep deprivation on simple reaction time. Twelve young, healthy volunteers (M=21.5 years, ?=2.3) performed a random generation task involving letters and a simple reaction time psychomotor test over four sessions held at 10-hour intervals. Each participant was assigned a "constant routine." Participants were kept awake in a prone position within a room whose environment was held strictly constant (light, noise, temperature, meals, etc.). This control procedure provided assurance that any variation in participant performance was solely caused by sleep deprivation. The random generation task, nearly two minutes in length, consisted in verbally producing a sequence of 100 letters in a random fashion (i.e. by inhibiting, for example, alphabetical order) and by keeping to a set rhythm... (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
借助数值模拟方法对四角切圆煤粉锅炉进行三维稳态数值模拟,观察其炉内燃烧过程,重点对比了在空气分级下不同配风方式对炉内空气流动和燃烧特性的影响。结果表明:底部配风量较多的正宝塔型、均等、缩腰型配风在炉膛底部形成较高切圆且温度较高,主燃区上部风量较小的正宝塔型和鼓腰型配风速度分布均匀,温度偏差较小,倒宝塔型和鼓腰型配风时出口NOx较其他3种配风方式要小。  相似文献   
7.
Abstract. In this paper we establish a statistical methodology for the spectral analysis of stationary multivariate time series via the Walsh-Fourier transform. Theoretical results pertaining to the definition and estimation of the Walsh-Fourier spectral matrix and functions of that matrix including cross-spectra, coherency and phase are given. An example of the statistical techniques developed in this paper is given; in particular, the methodologies are applied to neonatal sleep data collected from a study of the effect of maternal substance use during pregnancy.  相似文献   
8.
在现代社会中,平板电脑、智能手机在人们日常生活的方方面面发挥着巨大的作用。通过分析电子产品在儿童和青少年的视力、身体发育、社交能力和学习能力等方面的负面影响,提出了加强亲子陪伴、合理引导控制等应对措施。  相似文献   
9.
常豆  宋美娜  杨俊 《软件》2014,(7):40-43
当今社会,随着信息和通信技术的飞速发展,数字信息正在被广泛使用,为了进行数据分析以支撑基于信息的决策,政府、社会机构、公司和个人都可能会收集一些涉及个人的信息数据,然而伴随着大数据资源的正在进行越来越广泛的整合、分析和利用,使得数据治理问题,特别是数据隐私保护问题也越来越被人们重视,成为大数据研究的一个重点。本文针对如何保证数据资源在使用过程中的安全访问控制问题,在主流的基于角色的访问控制方式的思路之上进行了扩展,提出了一种基于角色和数据项的访问控制方式,即在数据库中增加角色对数据表中每一项的访问权限表。实践结果表明,与目前主流的几种访问控制模式相比,实现了对数据的精细化管理,对不同角色的用户访问实现了数据可控,对大数据环境下信息系统的数据隐私保护具有一定的指导意义。  相似文献   
10.
分析了典型无线传感器网络路由算法的基础上,提出了路由算法的目标,并设计了能量敏感的路由算法,以节省能量消耗达到延长整个网络生命周期的目的.该路由算法由4个模块组成:分簇模块、簇头选举模块、休眠状态模块和簇间路由模块组成.在实验室提供的实验床基础上。实现了路由算法的原型,并对算法进行了有效的验证.  相似文献   
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