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1.
Kalai Selvan Ramalingam Karmegam Karuppiah Shiamala Devi Ramaiya Vivien How Enoch Kumar Perimal Hassan Sadeghi Naeini Sivasankar Sambasivam Kulanthayan KC Mani 《人机工程学与制造业中的人性因素》2019,29(5):426-434
Many occupations require workers to stand for long periods of time without proper interventions, which causes discomfort in the back and lower limbs. Therefore, this study aims to assess the effectiveness in alleviating body muscle discomfort during prolonged standing through the use of a calf massager. This study was conducted among male workers at a manufacturer with production line workers and the list was obtained from the HR Department and simple random sampling was done by number categorization. A total of 100 respondents (50 respondents for both the control and the experimental groups) participated in this study. The experiment took place in a room with a similar setup for the production line. Each respondent was requested to perform the simulated task for 2 hr. For the experimental group, the calf massager was turned on every 15 min. At every 15‐min interval after turning on the calf massager, respondents from both groups were required to evaluate their discomfort level on a Borg's scale CR‐10 questionnaire. The results showed that the level of body discomfort among respondents in the experimental group reduced (20–30%) compared with that of the control group. Multivariate analysis results revealed that the discomfort rating for the lower back, knees, thighs, calves, and feet was significantly lower (p < .05) among the experimental group compared with the control group. For lower body parts, the lower back region was statistically significant (p < .05) at the 90th, 105th, and 120th min; the thigh region was statistically significant (p < .05) at the 120th min; the knee region was statistically significant (p < .05) at the 105th and 120th min; the calf region was statistically significant (p < .05) at all minute intervals except the 15th and 45th min, while the feet region, was statistically significant at the 105th and 120th min. Therefore, this study indicates that calf massage treatment is capable of reducing body muscle discomfort during prolonged standing and highlights the significance of calf massage. 相似文献
2.
从电子商务在我国迅速发展的角度出发,系统地介绍了我国电子商务网站的典范:阿里巴巴、淘宝。从电子商务的模式出发分析了其经营理念,成功因素及其不足,对中国的电子商务目前状况作了分析,并提出展望。 相似文献
3.
在国际工程承包中,银行保函是一种常用的担保形式,也是商业银行表外业务的一种。笔者主要介绍保函的种类、办理银行保函的一般程序、开具银行保函的注意事项等内容,为从事国际工程承包业务的管理提供参考。 相似文献
4.
杨文静 《广东工业大学高等工程教育研究》2007,7(1):23-25
信用经济是市场经济发展到一定阶段的必然趋势和客观要求。在这种经济中,信用不仅仅是作为交换媒介存在,更为重要的是信用作为除市场以外的另一种资源配置方式。它的产生需要一些特定的条件,文章即从个人、企业、政府三方面信用建设入手,提出创建信用经济条件产生的具体措施。 相似文献
5.
Art Owen 《Data mining and knowledge discovery》2003,7(1):101-113
Data squashing was introduced by W. DuMouchel, C. Volinsky, T. Johnson, C. Cortes, and D. Pregibon, in Proceedings of the 5th International Conference on KDD (1999). The idea is to scale data sets down to smaller representative samples instead of scaling up algorithms to very large data sets. They report success in learning model coefficients on squashed data. This paper presents a form of data squashing based on empirical likelihood. This method reweights a random sample of data to match certain expected values to the population. The computation required is a relatively easy convex optimization. There is also a theoretical basis to predict when it will and won't produce large gains. In a credit scoring example, empirical likelihood weighting also accelerates the rate at which coefficients are learned. We also investigate the extent to which these benefits translate into improved accuracy, and consider reweighting in conjunction with boosted decision trees. 相似文献
6.
自动传输收视率调查系统 总被引:1,自引:1,他引:0
综述了当前收视率调查的主要方法 ,提出一种自动传输的收视率调查系统 ,详细介绍了该系统的组成、原理和设计思想 ,并分析了不同实现方法的优点与不足。应用表明 ,该系统在同类产品中具有明显优势 相似文献
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8.
Burns G. Leonard; Gomez Rapson; Walsh James A.; de Moura Marcela Alves 《Canadian Metallurgical Quarterly》2003,15(1):118
G. J. DuPaul (see record 2003-02033-012) offered two suggestions for additional research to understand the strong source effects reported by R. Gomez, G. L Burns, J. A. Walsh, and M. A. de Moura (see record 2003-02033-001) in attention-deficit/ hyperactivity disorder (ADHD) rating scales. The first suggestion was to determine whether the source effects represent mostly bias or accuracy. The second suggestion was to minimize source effects through the development of better ADHD rating scales. Because source effects can represent bias or accuracy, it is important to minimize the bias aspect through content validation procedures prior to attempts to determine whether source effects better reflect bias or accuracy. This comment offers various suggestions to reduce the bias in ADHD rating scales. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
诚信:中国企业亟待解决的问题 总被引:1,自引:0,他引:1
分析论述了诚信的重要性,指出了在维系市场秩序中诚信处于十分重要的地位。分析了中国企业诚信的现状,提出了企业重塑诚信的措施。 相似文献
10.