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991.
BackgroundNurses are a risk group for work-related musculoskeletal disorders (WMSDs). Several studies reveal that nurses have high prevalence rates of injuries and symptoms related to WMSDs. However, many of these studies focus mostly on hospital nurses. Worldwide, few studies include home care nurses.ObjectiveThis work aimed to identify the body region most affected by musculoskeletal complaints in home care nursing, and subsequently develop a statistical model, that includes the main risk factors, to predict the risk of having musculoskeletal complaints in the identified region.MethodsThe research method was based on the Standardised Nordic Questionnaire applied to home care nurses working at Health Centres of northern Portugal. Univariate and multivariate models of logistic regression were used to meet the goals of this work.ResultsHome care nurses have a three times greater chance of having lumbar complaints than their counterparts working only at Health Centres (OR = 3.19 (p < 0.05), with a 95% confidence interval [1.256; 8.076]). A statistical model with seven variables (forearm posture; static postures; arm posture; arm supported; bed height; job satisfaction; assistive devices) was obtained to predict lumbar complaints.ConclusionsThe lumbar region was identified as the most affected by musculoskeletal complaints. These complaints were associated with seven factors. 相似文献
992.
基于地域乡土观念的金梅湖乡村文化活动中心建筑规划设计 总被引:1,自引:0,他引:1
基于乡土观念的现象与特点,探讨了在城市化进程中乡村文化活动空间设计的定位、原则及方法,以金梅湖乡村文化活动中心建筑设计为例,其设计遵从表达乡村文化地域特色与提升乡村生活品质并重的思路,以期带给乡村经济、社会以及环境的平衡、健康发展。 相似文献
993.
介绍软伺服放大器控制系统的组成及其控制方法。实际应用结果表明:软伺服放大器控制系统的灵敏区、迟钝区和死区可以任意设定,且死区可以设定很小,控制精度高达0.1%,解决了长期困扰自动控制系统的硬伺服放大器死区大、控制精度低的问题。 相似文献
994.
Tony Salvador John W. Sherry Alvaro E. Urrutia 《Information Technology for Development》2013,19(1):77-95
About 10% of the world has access to information and communication technologies (ICTs). Telecenters and cyber cafés are one prevalent way to increase access. This paper suggests increasing access through currently existing, local businesses where people already gather and where proprietors already posses existing business relationships with suppliers and customers. This paper questions the prevailing emphasis on the “cyber'' characteristics of access, e.g., computing and internet access as is currently known, and attempts to refocus the conversation by considering computing and access in the context of the “café,” e.g., as public life in the sense of Habermas, which permits an in situ evolution of relevant access. This analysis is based on extant literature and direct ethnographic research in several public places in six countries. We offer example design perspectives based on a reflection of “third places” as inspiration for appropriate innovation in the provision of computing and communications. © 2005 Wiley Periodicals, Inc. 相似文献
995.
《Drug development and industrial pharmacy》2013,39(4):379-384
Background: Amitriptyline (AMT) is a tricyclic antidepressant with demonstrated local analgesic effects in human skin. Aim: We investigated the feasibility and mechanisms of iontophoretic delivery of AMT to rabbit dermis and plasma. Method: Two microdialysis probes were inserted into the upper dorsal shaved skin of tranquilized rabbits. After 1 hour, an iontophoresis cartridge was placed on top of one probe. The cartridge consisted of a stainless steel electrode covered with a pad that was filled with a 4.3 % AMT glycerin/water (50:50). Iontophoresis was performed at 100, 200, or 300 μA/cm2 constant-current density for 60 minutes. Dialysate samples were collected every 8 minutes for 3 hours and analyzed for AMT via a validated high-performance liquid chromatographic assay. Retrodialysis was performed at the other site. Blood samples were collected serially for 4 hours. Results: In vivo retrodialysis recovery was 89 ± 2%. AMT skin exposure increased non-proportionally with current density: AUCs were 19 ± 7, 119 ± 56, and 615 ± 302 mg/L/min for the 100, 200, and 300 μA/cm2, respectively, and Cmax were 107 ± 15, 1070 ± 537, and 5870 ± 1289 μg/L. In vivo plasma concentrations were always below LLOQ (0.1 μg/mL). Conclusion: AMT can be administered by iontophoresis and produces significant skin concentrations and negligible plasma levels. 相似文献
996.
对于没有压缩机组的储配站来说,在出站压力一定的情况下,由于站场内部的压力损失,其进站压力受到一定的限制。针对此情况,笔者对站场的压力损失展开研究,并深入分析了确定管段局部压力损失的途径,得到直接利用求得的管段总局部阻力系数计算局部压力损失的方法。然后,通过对实际站场的研究,最终确定不同流量下该储配站进、出站压力的匹配情况。这样既可以指导调度中心决策的制定,又能够为站场压力调节工作提供依据,有效避免了调度中心与站场之间工作中的矛盾。 相似文献
997.
随器补偿是新生事物,优点很多,但要推行起来,一些技术问题还难以解决,主要是安装位置的选择、补偿容量的确定、以及随器补偿电容器保护问题。文章结合当前城乡电网具体情况,针对这些难点问题进行探讨,提出了解决这些难点的意见。 相似文献
998.
999.
《国际计算机数学杂志》2012,89(12):2201-2217
We propose a trust region multidimensional filter SQP algorithm. The multidimensional filter technique proposed by Gould et al. [SIAM J. Optim., 15 (2005), pp. 17–38] is extended to solve constrained optimization problems. The constraints are partitioned into p parts. The entry of our filter consists of these different parts. Not only the criteria for accepting a trial step would be relaxed, but also the individual behaviour of each part of the constraints is considered. The filter's entries and the acceptance criteria are different from other filter-related algorithms in the literature. It should be noted that the undesirable link between the objective function and the constraint violation function in the filter acceptance criteria disappears. Our algorithm is also combined with the non-monotone technique for accepting a trial step, which leads to a more flexible acceptance criteria. Under mild conditions, global convergence is proved. Numerical results show the robustness and efficiency of our algorithm. 相似文献
1000.
Yuming Sun 《International journal of control》2013,86(12):1952-1966
Balancing control is important for biped standing. In spite of large efforts, it is very difficult to design balancing control strategies satisfying three requirements simultaneously: maintaining postural stability, improving energy efficiency and satisfying the constraints between the biped feet and the ground. In this article, a proportional-derivative (PD) controller is proposed for a standing biped, which is simplified as a two-link inverted pendulum with one additional rigid foot-link. The genetic algorithm (GA) is used to search for the control gain meeting all three requirements. The stability analysis of such a deterministic biped control system is carried out using the concept of Lyapunov exponents (LEs), based on which, the system stability, where the disturbance comes from the initial states, and the structural stability, where the disturbance comes from the PD gains, are examined quantitively in terms of stability region. This article contributes to the biped balancing control, more significantly, the method shown in the studied case of biped provides a general framework of systematic stability analysis for certain deterministic nonlinear dynamical systems. 相似文献