• 한국안전학회지
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• 제23권5호
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• pp.67-72
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• 2008

The lower flash points for the flammable binary systems, 2-propanol+formic acid and 2-propanol+n-butyric acid, were measured by Cleveland open cup tester. The optimization method using van Laar equation and the Raoult's law were used to estimate the lower flash points and were compared with experimentally-derived data. The calculated values based on the optimization method were found to be better than those based on the Raoult's law.

• 한국산업보건학회지
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• 제28권4호
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• pp.382-392
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• 2018

Objective: Allergic diseases such as asthma due to fungal exposure in houses have increased, and proper management is urgent. Mold can grow in the air, floor, walls, and other areas according to environmental conditions, and there are many limitations to the conventional methodology for examining fungal exposure. For this reason, the degree of fungal contamination is being evaluated by ERMI (Environmental Relative Moldiness Index), a quantitative analysis method proposed by the EPA. In this study, we compared ERMI values between water-damaged dwellings and non-damaged ones to evaluate the effectiveness of Korean ERMI values. We also explored the association of ERMI values with the level of airborne mold and characteristics of dwellings. Methods: Floor dust was collected after installing a Dustream collector on the suction port of a vacuum cleaner. The collected samples were filtered to remove only 5 mg of dust, and DNA was extracted using the FastDNA SPIN KIT protocol. Results: The ERMI values were found to be 19.6 (-6.9-58.8) for flooded houses, 7.5 (-29.2-48.3) for leaks/condensation, and 0.8 (-29.2-37.9) for non-damaged dwellings. The airborne concentration of mold for flooded, leakage or condensed, and non-damaged houses were $684CFU/m^3$, $566CFU/m^3$, and $378CFU/m^3$, respectively. The correlation between ERMI values and the levels of airborne mold was low (R = 0.038), but a weakly significant association of the ERMI values with the concentration of particulate matter ($PM_{10}$) was observed as well(R=0.231,P<0.05). Conclusions: Our findings show that the reference value using ERMI can be used to distinguish water-damaged and non-damaged dwellings. It is believed that ERMI values could be a promising tool for assessing long-term fungal exposure in dwellings.

• 한국철학논집
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• 제39호
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• pp.115-142
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• 2013

본 연구는 해방 이후부터 70년대 말 산업화 시기까지 한국인이 중요시 여겼던 가치가 어떻게 변화하고 있는지 탐색하는데 목적이 있다. 두 시기에 대한 구분은 본 연구의 관점에서 볼 때, 한국사회, 혹은 한국인들의 가치체계 변화에 지대한 영향을 미친 역사적 사건을 중심으로 '전환기', '산업화 시기'로 구분하였으며 정치, 경제 및 사회적 요인들을 간략히 살펴봄으로써 시기별 가치를 살펴보고자 하였다. 연구 목적에 따라 시기별로 나타나는 주요가치와 인재상을 도출하고자 하였을 뿐만 아니라 하나의 가치가 어떻게 변모하고 있는지 탐색하였다. 시기별로 나타나는 주요가치와 인재상은 다음과 같다. 전환기의 주요가 치로는 예의와 규범을 제시하였고, 추구하는 인재상은 무실역행(務實力行)하는 자세가 강조되는 실천적 지식이었다. 산업화 시기의 주요가치로는 성실, 근면, 자조, 협동을 제시하였고, 추구하는 인재상은 경제발전에 필수적이고 강력한 직업능력을 갖춘 기능인이었다. 시기별로 지속적으로 탐색한 가치는 애국심이었다. 전환기의 애국심은 초기에는 전통적 지배구조의 붕괴와 지도자의 부재로 인하여 국가와 민족이 충의 대상이었다면 지도자의 선출과 국가의 건립 이후에는 새로운 지배구조가 형성되어 국가보다는 지도자나 상급자에 대한 충성으로 변모하는 경향을 보였다. 산업화 시기 애국심은 국가경제정책을 충실히 이행하고 반공정신으로 무장하여 북한을 압도하는 통일의지를 가지는 것 등으로 비교적 다른 시기에 비하여 목적성이 매우 뚜렷한 경향을 보였다.

• 한국환경보건학회지
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• 제34권5호
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• pp.395-402
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• 2008

Road traffic noise causes considerable disturbance and annoyance in exposed inhabitants. Particularly, arterial road noise is a significant environmental problem in many urban areas in which higher traffic volume and higher car speed occur. Arterial road noise became the target of this investigation in Seoul, South Korea. Noise levels were measured at four points that were based on distance from roadside at the same measurement site and under the conditions as reported by the National Institute of Environmental Research (NIER) in 1999. The average noise levels ($L_{eq,1h}$) of the arterial road was 80.3 dBA at 5 m, 77.4 dBA at 10 m, 73.7 dBA at 20 m, 70.9 dBA at 30 m. A comparison between 1999 and 2008's measurement values has shown that in 2008 noise level is up by about 1.5 dBA, traffic volume has increased by about 15.7%, while car speed has decrease by about 8%. The relationship between 2008' measured values and predicted values using the NIER Equation is low under 10 m from the roadside. The influence range of arterial noise is calculated at 26 m for road noise limits in daytime. In relation to the comparison between traffic volume and noise level, the equivalence in traffic volume (Light car+10xHeavy car) is higher than other variables.

• 한국가스학회지
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• 제22권2호
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• pp.52-58
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• 2018

가연성 액체 혼합물의 화재와 폭발의 위험성을 규정하는 가장 중요한 성질 중 하나는 인화점이다. 본 논문에서는 삼성분계 액체 혼합물인, n-nonane+n-decane+n-tridecane 계의 인화점을 Seta flash 밀폐식 장치를 사용하여 측정하였다. 실험값은 라울의 법칙을 이용한 방법과 다중회귀분석법에 의해 계산된 값들과 비교되었다. 라울의 법칙에 의한 계산된 결과의 절대평균오차는 $0.6^{\circ}C$이었다. 다중회귀분석법에 의해 계산된 결과의 절대평균 오차는 $0.4^{\circ}C$이었다. 절대평균오차에서 알 수 있듯이 다중회귀분석법에 의한 계산값이 라울의 법칙에 의한 계산값에 비해 측정값을 잘 모사하였다.

• 한국산업보건학회지
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• 제27권4호
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• pp.324-332
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• 2017

Objectives: Much scientific evidence indicate a positive association between moldy environments and respiratory illnesses and/or symptoms. However, few comprehensive assessments of mold have been performed for such settings. Spore counts or microscopic enumeration only may not be sufficient for evaluating fungal exposure. Recently, Mold Specific QPCR technology developed by the US EPA (Environmental Relative Moldiness Index, ERMI) has been widely used worldwide and great performance for assessing fungal exposure has been shown. Methods: We aimed to develop a Korean version of ERMI suitable for the distribution of fungal flora in Korea. Thirty dwellings in the Seoul and Incheon area were selected for sampling, and each was classified as 'Flooded, 'Water-damaged' or 'Non-water-damaged'. Results: Dust on the floor and airborne sampling were collected using an MAS100 and a 'Dustream' collector. Samples were analyzed by quantitative polymerase chain reaction(QPCR) for the 36 molds belonging to ERMI. Student t-test and ANOVA tests were carried out using SAS software. The median ERMI values of flooded, water damaged, and non-water damaged dwellings were 8.24(range: -5.6 to 27.9), 5.47(-25. 4 to 32.7), and -15.30(-24.6 to 14.8), respectively. Significant differences were observed between flooded and non-water damaged dwellings (P=0.001) and between water-damaged and non-water damaged dwellings (P=0.032). Conclusion: Our findings indicate that ERMI values attributed to dust samples in Korea could be applicable for the identification of flooded or water damaged buildings. However, much data is needed for continuously developing the Korean version of ERMI values.

• 산업경영시스템학회지
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• 제40권4호
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• pp.221-229
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• 2017

In the international businesses human resource elements acquired in different countries might have different values in varied industries due to the different quality of education and experiences in the original countries. Using selection models to evaluate expected values in earnings equation of human resource elements such as education and experiences etc. acquired in sending countries, system equations are expanded to examine also the values of science and engineering degrees in technology jobs with selectivity bias correction. This paper used the US census survey data of 2015 on earnings, academic degrees, occupations etc. The US has long maintained the policy of accepting more STEM workers than any other countries and helped maintaining own technological leadership. Assuming per capita GDP gap between the sending country and the US downgrades immigrant human resource quality, it rarely affects occupational selection but depresses earnings on average by two or more years' worth of education. Immigrant quality index in the sense of GDP gap appears to be a valid tool to assess the expected earnings of the worker with. Engineering degrees increase significantly the probability of selecting not only engineering jobs but also general management jobs, as well as increasing the expected earning additionally over nine years'worth of education. Getting a technology job is additionally worth about four years of education. Economics and business degrees are worth additionally almost six years of education but humanities degrees depress expected earnings. Since years after immigration does not very fast enhance earnings capacity, education level and English language ability might be more useful criteria to expect better future earnings by.

• 산업융합연구
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• 제16권3호
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• pp.17-22
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• 2018

최근 국내 화장품 시장이 빠르게 성장하면서 많은 사람들이 피부관리에 관심을 가지게 되었다. 이에 피부미용관련 직종 중 대표 직업군인 피부미용사들의 자신의 직업에 대한 직업존중감과 만족도를 조사하여 현재 뷰티산업에 종사하는 전문가들의 직업만족도를 알아보고자 하였다. 조사는 서울 및 경기지역에 거주하는 현직 피부관리사 289명을 대상으로 설문을 실시하였고 그 결과 응답자의 대부분은 자신의 직업존중감이 높은 것으로 나타났다(M=3.81). 그러나 남, 여에 따라 '정당한 대우'에서, 학력에 따라 '상대적 우위'에서 유의미한 차이를 보였다(p<.o1). 직업만족도에서도 M=3.34로 높은 만족도를 보였고 근무시간, 직위, 급여에 따라 유의미한 차이를 나타냈다. 자아존중감과 직업존중감이 높을수록 직업의식에 대한 직무만족도가 높아진다. 따라서 직업의 가치를 평가하는 사회적 인식 수준의 향상과 자신의 직무에 대한 긍정적인 가치관이 피부미용사들의 직업 만족도를 높여 직무능력 향상에도 도움이 될 것으로 생각된다.

• 한국정보통신학회논문지
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• 제26권9호
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• pp.1272-1278
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• 2022

정부는 2021년 1월에 '중대재해처벌법'을 제정 공포하여, 이 법을 시행하고 있다. 하지만, 2021년 산업재해 사고자수가 전년 동기 대비 10.7% 증가하였다. 따라서, 산업 현장에서는 안전대책이 시급한 현실이다. 본 연구에서는 통신 환경이 열악한 고위험 산업현장의 안전관리를 위하여 BLE Mesh 네트워킹 기술을 적용한다. 복합 센서 AIoT 디바이스로 가스 센싱값, 음성, 모션값을 실시간으로 수집하여, 인공지능 LSTM 알고리즘과 CNN 알고리즘을 통해 정보값을 분석하여 위험 상황을 인식하고, 서버에 전송한다. 서버에서는 전송 받은 위험정보를 실시간으로 모니터링 하여 즉각적인 구호조치가 수행되도록 한다. 본 연구에서 제안하는 AIoT 디바이스와 안전관리 시스템을 고위험군 산업 현장에 적용함으로써, 산업재해를 최소화하고 사회안전망 확대에도 기여할 것이다.

• 한국안전학회지
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• 제27권2호
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• pp.84-91
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• 2012

This study evaluated three forces (lifting, pushing and twisting) required to maneuver the single-wheel barrows according to handle height, width, horizontal angle and vertical angle. The four independent variables were varied in two levels. Handle height was varies in two levels : 'knuckle height (KH)' and 'KH + 0.1 ${\times}$ stature'. The two handle widths were '1.5 ${\times}$ shoulder width (SW)' and '1.75 ${\times}$ SW'. Two angles of $0^{\circ}$ and $15^{\circ}$ were used for horizontal and vertical angles. The 24 factorial design was used in the experiment. Twelve healthy male students (undergraduate and graduate) participated in the experiment. Subjects exerted three forces (pushing, lifting, and twisting clockwise) in each experimental condition. The order of 16 treatment conditions was determined randomly. Results showed that the effects of the four factors were different according to three forces. While lifting and twisting forces were higher in 'knuckle height', the pushing force was higher in 'KH + 0.1 ${\times}$ stature' (p < 0.05). Lifting and pushing forces showed higher values in the horizontal angle $0^{\circ}$ than in $15^{\circ}$. Handle width and vertical angle showed no statistically significant main effects on three forces (p > 0.05). Results of this study could be used as basic data for the ergonomic design of handle variables of one- or two-wheel barrows.