• Environmental and Resource Economics Review
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• v.17 no.1
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• pp.3-22
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• 2008

We study nonlinearities of $CO_2$ emissions and economic growth m Korea using the Smooth Transition Autoregressive (or STAR) model. We find evidence for nonlinearities and cyclical regime changes of both time series. In the extended nonlinear empirical work, we characterize dynamic properties of the two time series and then find mutually significant Granger causality between $CO_2$ emissions and economic growth. All these empirical evidences together reinforce long standing concern that economy-wide restrictions on $CO_2$ emissions would hurt economic growth for Korean styled medium industrialized countries.

• Journal of muscle and joint health
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• v.15 no.2
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• pp.175-182
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• 2008

Purpose: The purpose of the study was to identify low pain prevalence rate and factors affecting low back pain in emergency medical technicians. Method: A descriptive relationship research design was utilized. The participants were 74 emergency medical technicians who worked at fire stations in W and J city and agreed to participate in this study. Data were collected between April and August 2008 using a questionnaire, which included demographic factors, severity of low back pain using a visual analog scale, factors related to low back pain and health behavior, and BMI. Descriptive statistics and multiple regression were performed for data analysis. Results: 85.1% of emergency medical technicians experienced low back pain. The mean score of low back pain was relatively low (M=4.0, SD=2.33). Significant factors affecting low back pain were found to be age, marital status, exercise, hours of standing work, and BMI. These variables explained 35.1% of variance in low back pain (F=8.45, p<.001). Conclusion: These results suggest that further research is needed to develop interventions for prevention and management of low back pain among emergency medical technicians.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.296-296
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• 2013

Supercapacitor is a capacitor with extraordinarily high energy density, which basically consists of current collector, active material and electrolyte. Ruthenium oxide ($RuO_2$) is one of the most widely studied active materials due to its high specific capacitance and good electrical conductivity. In general, it is known that the coating of $RuO_2$ on nanoarchitectured current collector shows improved performance of energy storage device compared to the coating on the planar current collector. Especially, the surface structure with standing coaxial nanopillars are most desirable since it can provide direct paths for efficient charge transport along the axial paths of each nanopillars and the inter-nanopillar spacing allows easy access of electrolyte ions. However, well-known fabrication methods for metal or metal oxide nanopillars, such as the process using anodize aluminum oxide (AAO) templates, often require long and complicated nanoprocess.In this work, we developed relatively simple method fabricating indium tin oxide (ITO) nanopillars via sputtering. We also electrodeposited $RuO_2$ nanoparticles onto these ITO nanopillars and investigated its physical and electrochemical properties.

• Journal of the Korean Society of Safety
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• v.26 no.3
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• pp.75-82
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• 2011

The objective of this study was to identify risk factors associated with the occurrence of musculo-skeletal symptoms of cashiers and provide suggestions for an improved workspace design. Workload and exertion of each task were measured using job analysis and posture analysis. The three most time-consuming tasks were waiting (43.8%), scanning (23.5%) and payment transaction (22.9%). It was analyzed that the workspace can be improved by applying Korean anthropometric data to the design of the desk height. The most common posture was a standing posture with neutral back, and bent lower arms and hands. Finally, it was revealed that 'scanning' and 'payment transaction' seemed more stressful than other operations. The result of the ergonomic evaluation would be a useful basis for designing an improved workspace.

• Korean Journal of Heritage: History & Science
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• v.42 no.4
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• pp.112-131
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• 2009

The Trikaya Banner Painting in the Suta-sa Temple at Hongcheon-gun, Gangwon-do draws attention as it was painted not on flax but on paper, and used the water color painting technique on the sketch rather than the deep color painting technique, which is most common in Buddhist paintings created during the Chosun Dynasty. Nevertheless, there is not any information on the creation of the Trikaya Banner Painting in the painting record on the painting, in Sutasasajeok(壽陀寺史蹟), or in Sutasagogirok(壽陀寺古記錄), so it is uncertain when the painting was created. Furthermore, because it was not drawn by the deep color painting technique, it has been difficult to compare it with other banner paintings. For these reasons, the Trikaya Banner Painting has been studied little except brief introduction. In recent preservation treatment that removed multiple-layered paper from the back of the painting, however, an inked inscription written on Korean paper 118cm high and 87.5cm wide was discovered on the back. It is a kind of placard notifying a number of acts prohibited in order to follow Buddha's teachings correctly, and was found to have been written on April 15, 1690. The inked inscription is a very valuable material for estimating the creation date of the Suta-sa Trikaya Banner Painting, and provides crucial clues for approaching the contents and nature of the painting more precisely. When the image, form, and style of the Suta-sa Trikaya Banner Painting were examined and its creation date was estimated based on the inked inscription, first, the painting is presumed to have been created in around 1690 as suggested by 'the placard' attached on the back instead of a painting record. Second, the painting is highly likely to be the first standing Trikaya banner painting showing the basic icons of Trikaya banner paintings in the Chosun Dynasty since the Trikaya Banner Painting in the Gap-sa Temple in Gongju (1650). Furthermore, considering the shape of the Trikaya in the painting, screen composition, background treatment, solemn and affectionate facial expression, harmonious and adequate body proportion, etc., the painting is believed to have had a considerable influence not only on Trikaya banner paintings of similar style in the 18thcentury but also on deep-color Trikaya banner paintings in the 19thcentury. Third, although the Suta-sa Trikaya Banner Painting is not acompleted work but a sketch, it exhibits the typical water color painting technique in which the strokes are clearly visible. Thus, it is considered highly valuable in understanding and analyzing stroke styles and in studying the history of Buddhist paintings. As there are not many extant banner paintings of the same style in form and expression technique as the Suta-sa Temple Trikaya Banner Painting, this study could not make thorough comparative analysis of the work, but still it is meaningful in that it laid the ground for research on standing Trikaya banner paintings in the 18thand 19thcenturies in the Chosun Dynasty.

• Journal of Korean society of Dental Hygiene
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• v.4 no.2
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• pp.265-276
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• 2004

The purpose of this study,was to find out health status, characteristics related to working conditions, occurrence of low back pain and its related factors among dental hygienists working in dental clinics, and, thus, to provide basic information necessary to set up some plans for preventing the occurrence of low back pains and improving working conditions for dental hygienists. The data were collected from 310 dental hygienists working at dental clinics in Pusan and Kyungnam area, including Masan, Changwon, Jinhae and Jinju, with a self-administered questionnaire and were analyzed finally for 295 records with SPSS for Windows(7.52K) program. The results were as follows : Working condition was considered to be fair by 562% of dental hygienists were thought to threaten their health in the dental clinics. About seventy percent of dental hygienists worked over ten hours a day and 72.8% were standing while working over 7 hours, 65% considered working hours too long. Health status was thought be more than average for 82.3% while more than half perceived certain degree of stress frequently. The rate of complaining low back pains among dental hygienists was 87.8% with pains more than medium level for 39.3%. The variables significantly related to the degree of low back pains were height, uncomfortable postures, type of working postures and the height of working table, while some variables including height, hours of working on the feet, the presence of hazardous work environment, uncomfortable postures, the presence of hazardous works, the amount of working hours, type of working postures and work-associated stresses, were significantly related to the number of symptoms for low back pains. Multiple regression analysis showed that occurrence of low back pains was significantly influenced by 5 factors such as subjective status of health, work-related stresses, the degree of perception to work environment, the degree of perception to the amount of working hours and age. In conclusion, it might be necessary to manage working conditions effectively by reducing working hours, making good postures while working and removing stressful conditions in order to reduce risk factors for the occurrence of low back pains among dental hygienists. Therefore good working postures, assignment of appropriate rest time and some programs for early detection, care and education of low back pains should be provided for the dental hygienists.

• The Journal of the Korea Contents Association
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• v.12 no.8
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• pp.248-255
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• 2012

The purpose of this study was to examine the satisfaction of dental hygiene students receiving dental hygiene education with their major, their view of profession and the correlation between their satisfaction with major and view of profession in an attempt to provide some information on how to teach students to accept the occupation of dental hygienist as a profession. 1. As for satisfaction with major, the dental hygiene students were most satisfied with awareness of dental hygienist, and they were least satisfied with courses. 2. The major satisfaction score was 3.51. The students whose academic standing was higher and who wanted to work in a general hospital or university hospital expressed more satisfaction with their major(p<0.01, p<0.05). 3. Concerning view of profession, they placed the most significance on the independence of dental hygiene, and put the least value on social awareness. 4. The view of profession score was 3.48. The students whose academic standing was higher regarded the job of dental hygienist as a profession(p<0.05). 5. As to the relationship between satisfaction with major and view of profession, those who were more satisfied with their major gave more weight to the job of dental hygienist as a profession(p<0.001).

• Korean Journal of Applied Biomechanics
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• v.25 no.2
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• pp.183-190
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• 2015

Objective : Walking with a Material handling is an activity frequently undertaken by agricultural workers in Korea, due to the nature of their work. This study aimed to investigate differences in biomechanical variables according to the mechanical alignment of the lower limbs when walking with a heavy load, and to use this as basic data in the design of various working environments to reduce the skeletomuscular burden on the knee joint. Method : The study subjects comprised of 22 right-foot dominant adult men and women aged between 20 and 23 years. The subjects were divided into a varus or valgus group according to the mechanical alignment of the lower limb by using radiographic findings. The subjects walked without any load and with a load of 10%, 20%, or 30% of their body weight held in front of them. The Kwon3d XP program was used to calculate biomechanical variables. Results : The flexion/extension moment of the knee joint showed a decreasing trend with increased load, irrespective of the mechanical alignment of the lower limb, while the varus group did not show normal compensatory action when supported by one leg at the point of maximum vertical ground reaction force. In addition, in terms of the time taken, subjects showed no difficulties in one-foot support time up to 20%/BW, but at 30%/BW, despite individual differences, there was an increase in single limb. The increased load resulted in a decrease in the ratio of standing phase to ensure physical stability. The valgus group showed a trend of increasing the stability of their center of mass with increasing load, through higher braking power in the early standing phase. Conclusion : In conclusion, although there was no statistical difference in biomechanical variables according to the mechanical alignment of the lower limbs, the varus group showed a more irregular walking pattern with a Material handling than the valgus group, partially proving the association between lower limb alignment and walking with a Material handling.

• Journal of Nutrition and Health
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• v.13 no.1
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• pp.27-36
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• 1980

A dietary survey of 100 children, aged 5 to 6, of Y.C. Kindergarten located in Yowido apartment compound of Seoul, was conducted July 18 to August 21, 1979. The results are summarized as follows: General family environment: Ninety four percent of the subjects were from families having two to three children, without grandparents in the home. One hundred percent of fathers were educated at or above the college level, while 83.9% of mothers had completed college. Mothers' ages ranged from 30 to 40 years, with 58% in the $31{\sim}35$ age bracket. Nearly 60% of the fathers were office and government employees, 10% were professors and teachers, 30% were engaged in businesses and other work, while 91.3% of mothers were unemployed. Anthropometric measurements: Mean values of standing height, body weight, girth of head and girth of chest, ranged from the 75th to the 90th percentile of Korean standards. None of the subjects had anthropometric indicators below the 5th percentile, representing the malnutrition borderline, of the Korean standards; while 12%, 24%, 17% and 14% of subjects supposed the 97th percentile in standing height, body weight, girth of head, and girth of chest, respectively. Furthermore, 58% of subjects exceeded Jelliffe's standard in arm circumferences; 60%, in triceps skinfold thickness; and 14.5% of subjects exceeded 120% of the latter standard. From this data, a certain number of these children were judged to he rather overweight. Dietary intake: Mean intake per day of energy and of nutrients, excluding iron, reached or exceeded Korean recommended dietary allowances. The energy input ratio of carbohydrate: protein: fat was 61.4 : 13.2 : 25.4, showing lower dependance on carbohydrates and higher dependance on fat for energy needs, compared with the average for Korean children of the same age group. Mean FAO-protein score of each subject's diet was shown to be as high as 90.6. Energy intake was divided among breakfast, lunch, and evening meal, on the average, in a ratio of 19.6 : 24.1 : 23.0. Approximately 33.3% of the daily caloric intake came from the snacks. Nutrition Knowledge of mothers: Nutrition knowledge of mothers was highly scored. Mothers' self-evaluations of their knowledge of nutrition was highly correlated with attitudes toward nutrition behavior.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.30 no.1
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• pp.1-9
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• 2020

Objectives: The purpose of this case study is to assess workers' exposure to carbon nanotubes(CNTs) and characterize particles aerosolized during the process of producing CNT-enabled polytetrafuoroethylene(PTFE) composites at a worksite in Korea. Methods: Personal breathing zone and area samples were collected for determining respirable concentrations of elemental carbon(EC) using NIOSH(National Institute for Occupational Safety and Health) Method 5040. Personal exposure to nano-sized particles was measured as the number concentration and mean diameter using personal ultrafine particle monitors. The number concentration by particle size was measured using optical particle sizers(OPS) and scanning mobility particle sizers(SMPS). Transmission electron microscopy (TEM) area samples were collected on TEM grids and analyzed to characterize the size, morphology, and chemistry of the particles. Results: Respirable EC concentrations ranged from 0.04 to 0.24 ㎍/㎥, which were below 23% of the exposure limit recommended by NIOSH and lower than background concentrations. Number concentrations by particle size measured using OPS and SMPS were not noticeably elevated during CNT-PTFE composite work. Instant increase of number concentrations of nano-sized particles was observed during manual sanding of CNT-PTFE composites. Both number concentrations and mean diameters did not show a statistically significant difference between workers handing CNT-added and not-added materials. TEM analyses revealed the emission of free-standing CNTs and CNT-PTFE aggregate particles from the powder supply task and composite particles embedded with CNTs from the computer numerical control(CNC) machining task with more than tens of micrometers in diameter. No free-standing CNT particles were observed from the CNC machining task. Conclusions: Significant worker exposure to respirable CNTs was not found, but the aerosolization of CNTs and CNT-embedded composite particles were observed during handing of CNT-PTFE powders and CNC machining of CNT-PTFE composites. Considering the limited knowledge on the toxicity of CNTs and CNT composite particles to date, it seems prudent to take a precautionary approach for the protection of workers' health.