• Journal of Preventive Medicine and Public Health
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• v.27 no.3 s.47
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• pp.475-486
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• 1994

In order to provide necessary information for better health of workers through understanding the actual status of the industries adopting shift systems. The data were gathered from a stratified random sample of 347 (0.5%) firms selected out of about 70,000 manufacturing industries throughout the nation in 1993. Stratification during sampling was by industrial group and number of workers. The major findings obtained from 288 firms surveyed completely were as follows : 1. About 20.2% of the 288 firms were adopting shift systems and shirtworkers accounted for about 25.1% of the total work force in 288 firms. 2. The bigger number of workers was, the higher the adopting rate of shift system was. 3. The rate of having welfare facilities such as dining room, commuting bus, washing facilities, and health care room etc. was higher in the industries adopting shift systems. 4. The major industrial groups adopting shift systems were the rubber a: plastic goods manufacturing industry (54.1 per 100 firms) and the textile manufacturing industry (44.8 per 100 firms). However, the proportion of shiftworkers was higher in the textile manufacturing industry (70.5 per 100 firms) and the electronics industry (57.9 per 100 frms). 5. The most predominant work schedule was the weekly rotating, semi-continuos 2-crew 2-shift system (47.5%). 6. In the industries adopting shift systems, shiftworkers had an adjusted average of 0.29 spells per 100 workers ($0.14{\sim}0.45$ in 95% C.I.) compared to 0.23 spells per 100 nonshift dayworkers ($0.15{\sim}0.31$ in 95% C.I.) for 1 month. 7. Also, in the industries adopting shift systems, the adjusted average annuel turn-over rate of shiftworkers was 13.07 per 100 workers ($12.03{\sim}14.12$ in 95% C.I.) compared to 10.18 per 100 nonshift dayworkers ($9.53{\sim}10.82$ in 95% C.I.).

• Journal of Korea Entertainment Industry Association
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• v.14 no.7
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• pp.477-485
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• 2020

This study is a random allocation similar experimental study to compare and analyze the difference in BVM (Bag-Valve-Mask) ventilation volume according to the characteristics of the rescuer's hand and the type of mask using a standardized mannequin. To this end, the Basic Life Resuscitation Education Center of D University in gwangju. Recruiting 39 students who have completed the basic resuscitation course for emergency medical personnel and the Korean-style specialized cardiac rescue course, In addition to measuring the physical characteristics of the hand, the average amount of ventilation per minute using a bag-mask was measured and analyzed. As a result, the type of mask that was not most affected by the characteristics of the hand and provided adequate Minute Ventilation was the soft type (tube, silicone) mask. On the other hard (tube, silicone) masks were found to be unsuitable for general use as they were greatly affected by the characteristics of workers' hands. COVID-19 is currently increasing the risk of transmission to paramedics and patients. Considering this situation, the universal use of a semi-permanent hard-type mask, which is disadvantageous not only for preventing infection but also for proper ventilation, should be avoided. In addition to the ease of use, it should be actively utilized in the field by supplying a soft type mask that can provide stable ventilation even with 'predominance recognition' and proper ventilation.

• Korean Journal of Radiology
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• v.22 no.7
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• pp.1044-1053
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• 2021

Objective: Motion-corrected averaging with a single-shot technique was introduced for faster acquisition of late-gadolinium-enhancement (LGE) cardiovascular magnetic resonance (CMR) imaging while free-breathing. We aimed to evaluate the image quality (IQ) of free-breathing motion-corrected single-shot LGE (moco-ss-LGE) in patients with hypertrophic cardiomyopathy (HCM). Materials and Methods: Between April and December 2019, 30 patients (23 men; median age, 48.5; interquartile range [IQR], 36.5-61.3) with HCM were prospectively enrolled. Breath-held single-shot LGE (bh-ss-LGE) and free-breathing moco-ss-LGE images were acquired in random order on a 3T MR system. Semi-quantitative IQ scores, contrast-to-noise ratios (CNRs), and quantitative size of myocardial scar were assessed on pairs of bh-ss-LGE and moco-ss-LGE. The mean ± standard deviation of the parameters was obtained. The results were compared using the Wilcoxon signed-rank test. Results: The moco-ss-LGE images had better IQ scores than the bh-ss-LGE images (4.55 ± 0.55 vs. 3.68 ± 0.45, p < 0.001). The CNR of the scar to the remote myocardium (34.46 ± 11.85 vs. 26.13 ± 10.04, p < 0.001), scar to left ventricle (LV) cavity (13.09 ± 7.95 vs. 9.84 ± 6.65, p = 0.030), and LV cavity to remote myocardium (33.12 ± 15.53 vs. 22.69 ± 11.27, p < 0.001) were consistently greater for moco-ss-LGE images than for bh-ss-LGE images. Measurements of scar size did not differ significantly between LGE pairs using the following three different quantification methods: 1) full width at half-maximum method; 23.84 ± 12.88% vs. 24.05 ± 12.81% (p = 0.820), 2) 6-standard deviation method, 15.14 ± 10.78% vs. 15.99 ± 10.99% (p = 0.186), and 3) 3-standard deviation method; 36.51 ± 17.60% vs. 37.50 ± 17.90% (p = 0.785). Conclusion: Motion-corrected averaging may allow for superior IQ and CNRs with free-breathing in single-shot LGE imaging, with a herald of free-breathing moco-ss-LGE as the scar imaging technique of choice for clinical practice.