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排序方式: 共有1326条查询结果,搜索用时 31 毫秒
1.
Fluorescence‐Activated Cell Sorters: Standing Surface Acoustic Wave (SSAW)‐Based Fluorescence‐Activated Cell Sorter (Small 40/2018)
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2.
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
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A system for person-independent classification of hand postures against complex backgrounds in video images is presented. The system employs elastic graph matching, which has already been successfully applied for object and face recognition. We use the bunch graph technique to model variance in hand posture appearance between different subjects and variance in backgrounds. Our system does not need a separate segmentation stage but closely integrates finding the object boundaries with posture classification. 相似文献
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Two studies examine complementarity (vs. mimicry) of dominant and submissive nonverbal behaviors. In the first study, participants interacted with a confederate who displayed either dominance (through postural expansion) or submission (through postural constriction). On average, participants exposed to a dominant confederate decreased their postural stance, whereas participants exposed to a submissive confederate increased their stance. Further, participants with complementing responses (dominance in response to submission and submission in response to dominance) liked their partner more and were more comfortable than those who mimicked. In the second study, complementarity and mimicry were manipulated, and complementarity resulted in more liking and comfort than mimicry. The findings speak to the likelihood of hierarchical differentiation (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Infants' sensitivity to optical flow for controlling sitting and standing was tested using a "moving room" in which all of the walls moved together, or only the side walls or front wall moved. Two questions motivated this research. (a) is the optical flow necessary for inducing postural compensations spatially distributed in the optic array? (b) Do visually induced compensations follow a developmental progression, or alternatively, emerge all at once? Experiment 1 was designed to test postural compensations by 14-month-old infants capable of standing in the moving room. Experiment 2 was designed to test postural compensations by 5- to 9-month-old infants who were passively supported while sitting in the moving room. The results revealed that partial flow is generally sufficient for inducing postural compensations, but that the amplitude and consistency of the response depend on the location of the flow in the optic array. In addition, there was evidence suggesting that compensatory responses become increasingly systematic during the second half of the first year. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Office workers perform tasks using different information and communication technologies (ICT) involving various postures. Adequate variation in postures and muscle activity is generally believed to protect against musculoskeletal complaints, but insufficient information exists regarding the effect on postural variation of using different ICT. Thus, this study among office workers aimed to determine and compare postures and postural variation associated with using distinct types of ICT. Upper arm, head and trunk postures of 24 office workers were measured with the Physiometer® over a whole day in their natural work and away-from-work environments. Postural variation was quantified using two indices: APDF(90-10) and EVA(sd). Various ICT had different postural means and variation. Paper-based tasks had more non-neutral, yet also more variable postures. Electronics-based tasks had more neutral postures, with less postural variability. Tasks simultaneously using paper- and electronics-based ICT had least neutral and least variable postures. Tasks without ICT usually had the most posture variability. Interspersing tasks involving different ICT could increase overall exposure variation among office workers and may thus contribute to musculoskeletal risk reduction. 相似文献
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Neck injury is a severe problem in traffic accidents. While most studies are focused on the neck injury in rear and front impacts, few are conducted in side impact. This study focuses on the difference of neck injury under different postures and the difference of 7 cervical vertebras under the same posture using the method of prescribed structure motion(PSM). The analytical results show that the maximum changes of mean force and mean moment of 7 cervical vertebras under 8 different postures are 20% and 47% respectively. The variation of each cervical vertebra is different under different neck postures. Up cervical vertebras (C1-C4) and low cervical vertebras (C5-C7) suffer different forces and moments under the same neck posture. Generally speaking, No.6 (neck right leaning 40°) is the posture with lowest neck injury risk. 相似文献