• Journal of Korean Society for Quality Management
• /
• v.46 no.2
• /
• pp.301-310
• /
• 2018

Purpose: The purpose of this study is to investigate the effect of work intensity on fit factor and affective quality of the dustproof Background: Among the victims who suffer pneumoconiosis due to the inhalation of toxic substances or the lack of oxygen during the work, the proportion of the victims is larger than the other causes. Wearing a respirator may prevent pneumoconiosis, but it can be hazardous to workers because of the leakage through filters, cartridges, exhaust valves, broken parts, and face-to-face contact. Despite leakage through the contact area between the mask and the face has various causes such as the wearer's activity, sweat accumulation, facial shape, etc., There is a lack of relevant research and regulation compared to developed countries that have already institutionalized the law 30 years ago and give the right to sell through a test Method: The work intensity was adjusted by walking or running at 6km/h and 11km/h on the treadmill, and tasks were defined with reference to the test procedure and the exercise sequence applied in the face leakage test of the dustproof mask. And fit factor was measured objectively using 'Respirator Fit Tester 8038' which measures fit factor calculated by dividing the number of dust present outside the mask by inside the mask. In addition, affective quality was classified by the ease of use, ease of breathing, and ease of wearing, and was measured using the 5-point likert scale questionnaire. Results: There was a significant difference in fit factor, ease of breathing, and wearing convenience according to work intensity and no significant difference in ease of use(${\alpha}=0.01$). And when the work intensity was high, fit factor, ease of breathing, and wearing convenience were all lower than when the work intensity was low. Conclusion: In Korea, it is necessary to consider consideration of the work intensity when testing the leakage rate of the face part for safety certification of the respiratory protective equipment, When developing a mask, it should be possible to maintain high adhesion even under intense, active situation and high temperature conditions by selecting materials, improving the wearing style, and expanding the adjustable range.

• Journal of the Korean Society of Physical Medicine
• /
• v.5 no.3
• /
• pp.455-465
• /
• 2010

Purpose : This study is intended to examine the motor skill learning on balance and coordination in the cerebellar injured rats by 3AP. Methods : This study selected 60 Sprague-Dawley rats of 8 weeks. Experiment groups were divided into four groups and assigned 15 rats to each group. Group I was a normal control group(induced by saline); Group II was a experimental control group(cerebellar injured by 3AP); Group III was a group of motor skill learning after cerebellar injured by 3AP; Group IV was a group of treadmill exercise after cerebellar injured by 3AP. In each group, motor performance test, histologic observations, synaptophysin expression and electron microscopy observation were analyzed. Results : In motor performance test, the outcome of group II was significantly lower than the group III, IV(especially group III)(p<.001). In histological finding, the experimental groups were destroy of dendrities and nucleus of cerebellar neurons. Group III, IV were decreased in degeneration of cerebellar neurons(especially group III). In immunohistochemistric response of synaptophysin in cerebellar cortex, experimental groups were decreased than group I. Group III's expression of synaptophysin was more increased than group II, IV. In electron microscopy finding, the experimental groups were degenerated of Purkinje cell. Conclusion : These result suggest that improved motor performance by motor skill learning after harmaline induced is associated with dynamically altered expression of synaptophysin in cerebellar cortex and that is related with synaptic plasticity.

• Journal of Life Science
• /
• v.24 no.9
• /
• pp.959-966
• /
• 2014

This study was carried out to develop a functional healthy drink using 60% ethanol of dried Acanthopanax senticosus stem extract (ASE). The preparation, physical activity, anti-oxidant activity, and sensory properties of ASE were investigated. The moisture, crude protein, crude lipid, and ash contents of dried ASE were $6.50{\pm}0.12%$, $5.89{\pm}0.16%$, $1.18{\pm}0.11%$, and $3.03{\pm}0.40%$ respectively. The 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity was $87.42{\pm}1.63%$ at 1/10 folds diluted ASE. In total, 40 male ICR mice were divided into five groups including the control (PBS), positive control (Red ginseng 200 mg/kg/day), and ASE-treated groups at doses of 35, 70, and 140 mg/kg/day for five weeks, respectively. ASE was administrated orally one time per day for five weeks before treadmill exercises, and normal and positive controls were fed PBS and red ginseng extract. In the treadmill test, ASE-treated mice (140 mg/kg/day) could run 1.4 times longer than the control mice. Healthy drinks were prepared with the addition of ASE at levels of 0.97% or 0.49% (A, B, and C type). Among the healthy drinks, the B type (ASE, 0.97%) was revealed to have the highest level of taste and overall acceptability through a sensory evaluation. The brix and pH of the ASE health drink (B type) were 14.9 and 4.51, respectively. These results indicated that the dried stem of Acanthopanax senticosus could be used as a functional material in the health drink industry.