벚꽃엔딩과 사학연금

정명구(Jung, Myunggu),고우림(Ko, Woorim),조영태(Cho, Youngtae) 한국인구학회 2021 한국인구학 Vol.44 No.4

국민연금과 공무원연금과 비교하면 그동안 사학연금의 지속가능성에 대한 사회적 관심은 매우 적었다. 심지어 사학연금 가입자 중 연금의 적자 혹은 기금고갈 시점이 언제로 예상되고 있는지 제대로 알고 있는 사람도 거의 없을 정도다. 그런데 공적연금제도들 가운데 위기가 가장 먼저 찾아올 연금제도는 사학연금이다. 왜냐하면, 사학연금 기여분의 약 70%는 대학종사자들에게서 나오고 대학종사자들의 임금은 학생들의 등록금 수입에 전적으로 의존하고 있는데, 초저출산 현상으로 촉발된 대학생 수의 감소는 사학연금 기여분의 감소로 이어질 수밖에 없기 때문이다. 본 연구 단편은 2021년부터 시작된 대학생 수 감소가 사학연금기금에 앞으로 어떤 재정적 어려움을 초래할 것인지 고찰하였다. 이를 통해 약 33만 사학 종사자들의 노후를 보장해야 할 사학연금기금의 지속가능성에 얼마나 심각한 위기가 다가오고 있는지 논의하였다. In comparison with national and civil-service pension schemes, too little attention has been paid to the sustainability of the Private teachers" pension (PTP) system in South Korea. Moreover, most pension participants in the PTP are not well aware of and are not even interested in when the PHP will be in deficit and depleted. Among public sector pension schemes, the PTP is highly likely to confront the most imminent pension crisis. About 70 percent of the PTP fund are contributed by university and college employees, and their salary relies heavily on tuition fee. This implies that the recent decrease in university and college freshers due to the low fertility in South Korea will inevitably lead to loss to the PTP reserves. This paper explores the financial sustainability of the PTP with respect to the unavoidable consequence of the decreasing number of students since 2021 and discusses the looming threat to financial sustainability of the PTP that should ensures the old-age income security for over 330 thousands pension participants in the PTP.

딥러닝을 활용한 회전체 이음감지 시스템 개발에 관한 연구

정해영(Haiyoung Jung),신호승(Hoseung Shin),정명구(Myunggoo Jung),이보희(Bohee Lee) 한국화재소방학회 2023 한국화재소방학회논문지 Vol.37 No.2

외기 오존 농도에 따른 반도체 작업환경 및 사무실에서의 오존 농도 변화 연구

이지은 ( Ji-eun Lee ),정명구 ( Myung-koo Jung ),최광민 ( Kwang-min Choi ) 한국산업보건학회 (구 한국산업위생학회) 2016 한국산업보건학회지 Vol.26 No.2

Objectives: The purpose of this study was to evaluate the ozone exposure levels and the variations in ozone concentration in asemiconductor fabrication facility and office in relation to the ozone concentration in the outdoor air. Methods: This study was performed in an office, semiconductor fabrication facility(such as etching, diffusion, diffusion plenum),and outdoors from June to August, 2015. Measurements were taken six times at the same places using an active sampler(pumped)and real-time equipment. Ozone monitoring by the active sampler method and analysis were carried out by OSHA MethodID-214. Real-time measurement was carried out by ozone measuring equipment using a non-dispersive ultraviolet absorption method. Results: Ozone concentrations in the semiconductor fabrication facility and office were 0.7~7.1 ppb in area samples and0.72~4.07 ppb in real-time measurement, which were 0.88~8.88% of the occupational exposure limit. The concentration of ozonegenerated by a laser printer in the office was less than 2 ppb. There was not a significant difference between ozone concentrations before and after using the laser printer. The indoor/outdoor concentration ratio(I/O ratio) in the semiconductor fabrication facility and office was 0.05 and 0.06, respectively. Conclusions: All the samples contained ozone levels lower than the occupational exposure limit and it was confirmed that the concentration of outdoor ozone had no significant effect on indoor ozone concentration

반도체 메탈공정 및 1차 스크러버에서 생성되는 파우더 부산물의 물리화학적 특성분석

최광민 ( Kwang Min Choi ),정명구 ( Myung Koo Jung ),안희철 ( Hee Chul An ) 한국산업보건학회 2015 한국산업보건학회지 Vol.25 No.3

Objectives: The aim of this study is to identify physicochemical properties such as chemical composition, size, shape and crystal structure of powder byproducts generated from a metallization process and its 1st scrubber in the semiconductor industry. Methods: Powder samples were collected from inner chambers during maintenance of the W-plug process equipment (using tungsten hexafluoride as a precursor material) and its 1st scrubber. The chemical composition, size and shape of the powder particles were determined by field emission scanning electron microscopy (SEM) and transmission electron microscopy (TEM) equipped with an energy dispersive spectroscope (EDS). The crystal structure of the powders was analyzed by X-ray diffraction (XRD). Results: From the SEM-EDS and TEM-EDS analyses, O and W were mainly detected, which indicates the powder byproducts are tungsten trioxide (WO3), whereas Al, F and Ti were detected as low peaks. The powder particles were spherical and nearly spherical, and the particle size collected from the process equipment and its 1st scrubber showed 10-20 nm (agglomerates: 55-90 nm) and 16-20 nm (agglomerates: 80-120 nm) as primary particles, respectively. The XRD patterns of the yellow powder byproducts exhibit five peaks at 23.8 33.9 41.74 48.86 and 54.78 which correspond to the (200), (220), (222), (400), and (420) planes of cubic WO3. Conclusions: We elucidated the physicochemical characteristics of the powder byproducts collected from W-plug process equipment and its 1st scrubber. This study should provide useful information for the development of alternative strategies to improve the working environment and workers`` health.

국가 발전에 적합한 인구 특성 : 아시아 국가를 중심으로

고우림(Woorim Ko),조영태(Youngtae Cho),정명구(Myunggu Jung),원성호(Sungho Won) 경북대학교 사회과학연구원 2020 사회과학 담론과 정책 Vol.13 No.1

최근 세계 경제에서 아시아가 차지하는 중요성이 커지면서 아시아 국가들의 빠른 경제발전 속도에 기여하는 요소들에 대한 학술적 관심도 함께 커지고 있다. 그런데 다양한 요소들 중 상대적으로 주목받지 못하고 있는 요소가 ‘인구’다. 인구는 사회를 구성하는 기본요소이며, 생산자와 수요자의 역할을 동시에 하고 있기에 국가 발전에서 반드시 주목되어야 하는 요소다. 이에 본 연구는 아시아 국가들을 대상으로 경제 발전에 적합한 인구 특성이 무엇인지 경험적으로 고찰하였다. 1980년~2015년 아시아 19개국 인구의 양적(총 인구수, 합계 출산율, 유소년 부양비, 노년 부양비, 25세~49세 인구 비중) 및 질적(25세~49세의 평균 교육 년 수, 영유아 사망률)특성의 지표들과 경제 성장 지표인 1인당 GDP와의 연관성을 살펴보았다. 분석에는 통합 패널 모형(Pooled-OLS), 고정효과모형(Fixed-effect model), 확률효과모형(Random-effect model)이 활용되었다. 분석 결과 ‘유소년 부양비’, ‘25세~49세의 인구 비중’, ‘25~49세의 평균 교육 년 수’가 아시아 국가들의 발전에 기여하고 있는 것으로 나타났다. 본 연구는 아시아 국가를 중심으로 인구의 양적 및 질적인 특성들이 독립적으로 경제 성장에 미치는 영향이 있다는 것을 실증적으로 증명 하였으며, 이는 국가 경제 성장 정책에 인구 요소가 반드시 고려되어야 함을 시사한 결과다. The increasing importance of Asia in the global economy in recent years has led to increased academic interest in the factors that have contributed to the rapid economic development of Asian countries. Among the various factors, however, a relatively unfocused factor is the population. Population is a fundamental component of society, and it is a factor that must be noted in national development, because it serves as both a producer and a consumer. Therefore, this study empirically analyzed the characteristics of population characteristics suitable for economic development among Asian countries. The population characteristics include both quantitative aspects (total population, total fertility rate, child age dependency ratio, old age dependency ratio, proportion of 25-49 year) and qualitative aspects (Average years of schooling 25-49 years, Morality under 5 years). For analysis, Pooled-OLS, Fixed-effect model, and Random-effect model were used. Results showed that ‘Child dependency ratio’, ‘Proportion of 25~49 years’, and ‘Average schooling years of 25~49 years’ are contributing to the economic development of Asian countries. This study empirically divulged which quantitative and qualitative characteristics of the population have contributed to the economic growth among Asian countries. Authors suggest that demographic factors should be considered in nation’s economic growth policies, at least among Asian countries.

Low Booster Vacuum시의 브레이크 답력 문제 개선을 위한 연구

김종훈(Jonghoon Kim),김용두(Yongdoo Kim),정명구(Myoungkoo Jung) 한국자동차공학회 2010 한국자동차공학회 학술대회 및 전시회 Vol.2010 No.11

Due to emission limit, fuel economy and increased electronic parts, the problem of lowering of brake performance caused by lack of booster vacuum is coming to the fore. To solve this problem, very expensive part like EVP and venturi system is applied because brake performance is directly linked to driver’s safety. The problem is related to high altitude and environment of sale area and the type of transmission. In this paper, it is stated that how booster vacuum is created and how booster vacuum level is changed according to engine and environment condition. And I will define the poor brake performance caused by lack of vacuum and discuss about validation method and process of brake vacuum performance development.

반도체 작업환경 내 부산물로 생성되는 실리카 입자의 크기, 형상 및 결정 구조

최광민 ( Kwang Min Choi ),여진희 ( Jin Hee Yeo ),정명구 ( Myung Koo Jung ),김관식 ( Kwan Sick Kim ),조수헌 ( Soo Hun Cho ) 한국산업보건학회 2015 한국산업보건학회지 Vol.25 No.1

Objectives: This study aimed to elucidate the physicochemical properties of silica powder and airborne particles as by-products generated from fabrication processes to reduce unknown risk factors in the semiconductor manufacturing work environment. Materials and Methods: Sampling was conducted at 200 mm and 300 mm semiconductor wafer fabrication facilities. Thirty-two powder and airborne by-product samples, diffusion(10), chemical vapor deposition(10), chemical mechanical polishing(5), clean(5), etch process(2), were collected from inner chamber parts from process and 1st scrubber equipment during maintenance and process operation. The chemical composition, size, shape, and crystal structure of silica by-product particles were determined by using scanning electron microscopy and transmission electron microscopy techniques equipped with energy dispersive spectroscopy, and x-ray diffractometry. Results: All powder and airborne particle samples were composed of oxygen(O) and silicon(Si), which means silica particle. The by-product particles were nearly spherical SiO2 and the particle size ranged 25 nm to 50 μm, and most of the particles were usually agglomerated within a particle size range from approximately 25 nm to 500 nm. In addition, the crystal structure of the silica powder particles was found to be an amorphous silica. Conclusions: The silica by-product particles generated from the semiconductor manufacturing processes are amorphous SiO2, which is considered a less toxic form. These results should provide useful information for alternative strategies to improve the work environment and workers‘ health.

지방인구정책의 문제점과 대안

김한나(Kim, Hanna),고우림(Ko, Woorim),임예진(Lim, Yejin),정명구(Jung, Myunggu),조영태(Cho, Youngtae) 한국인구학회 2020 한국인구학 Vol.43 No.4

본 연구단편은 우리나라 지방인구정책의 현황과 문제점을 비판적으로 검토하고 대안을 모색하기 위해 시도되었다. 현재 17개 광역지방자치단체들은 물론이고 200개가 넘는 기초지방자치단체들도 차별성을 거의 찾아볼 수 없는 인구정책을 추진하고 있는 것이 현실이다. 거의 모든 지자체들은 인구정책의 목표를 출산장려로 놓고 있고, 지역에 따라 금액이나 조건에는 차이가 있지만 현금성 출산장려금을 주된 인구정책으로 수행하고 있다. 인구변동의 원인과 속도에 지역 간 차이가 존재하기 때문에 지방정부는 중앙정부와는 차별화된 인구정책 혹은 각 지자체별로 차별화된 인구정책의 방향과 내용이 필요하다. 그럼에도 불구하고 저출산 · 고령사회기본계획이 진행된 지난 15년간 이처럼 천편일률적이면서도 실효성이 의심되는 인구정책을 대부분의 지방정부들이 수행해 왔다는 사실은 지방인구정책의 개념부터 시작하여 무엇을 왜, 그리고 어떻게 해야 하는가에 대한 근본적인 점검이 필요함을 시사한다. 본 연구단편은 출산장려만이 인구정책의 모든 것인 것처럼 되어 있는 현재의 지방인구정책을 비판하고, 그 대안으로 더욱 광범위한 개념의 인구정책을 제시하였다. 이제껏 지방정부가 추진해온 인구정책은 출산율과 총인구 수가 줄어가는 것을 ‘완화(mitigation)’하는 것을 목표로 해왔다. 본 연구는 오늘의 인구변동을 분석하여 지역의 변화를 미리 예측하여 어떻게 그 변화에 ‘적응(adaptation)’하는지, 혹은 아예 지역의 미래를 ‘기획(planning)’하는 것이 지방정부의 현실에 부합하며 더욱 절실하게 필요한 인구정책의 방향임을 제안하였다. This paper seeks to widen the scope of discussion by assessing both problems with and alternatives to local population policies in South Korea. Despite substantial differences in local contexts and characteristics 17 regional governments as well as more than 200 municipal governments in South Korea implement fairly similar population policies. The primarily target of population policies in most local governments is to promote childbirth with exclusive focuses on providing various forms of cash-transfer programs, albeit differently in the amount of and requirements for financial benefits. Since the causes and pace of population changes differ at different local areas, local governments should develop and identify appropriate population polices that actually reflect their local contexts and circumstances. However, over the past fifteen years since the establishment of the National Basic Plans for Low Fertility and Population Ageing, local governments in South Korea have carried out one-size-fits-all and seemingly ineffective population policies, which implies that it is the time to revisit the fundamental question from the concept to the what, why and how of population policy in local governments. This study criticizes the exclusively childbirth-centered local population policies and provides insight into a more comprehensive concept of population policy. This study further points out that local governments in South Korea have solely concentrated on ‘mitigation’ measures in response to fertility and population declines. Instead, local governments should be able to recognize and analyze current demographic signals in order to forecast beforehand the effects of population changes on local socio-economic development, which enables them to strategically prepare for ‘adaptation’ to imminent population changes or ‘planning’ for the future at the local level. In conclusion, this study demonstrates that the ‘adaption’ and ‘planning’ measures are more realistic and necessary population policy options for local governments in South Korea.

탈착용매에 따른 PAHs 흡착매체의 탈착효율 평가 연구

홍좌령 ( Jwa-ryung Hong ),이지은 ( Ji-eun Lee ),정명구 ( Myung-koo Jung ),최광민 ( Kwang-min Choi ) 한국산업보건학회 (구 한국산업위생학회) 2016 한국산업보건학회지 Vol.26 No.3

Objectives: In general, NIOSH method 5506 is most widely used for the occupational exposure measurement of PAHs, but 2-4 ring PAHs have poor desorption efficiency, especially for a filter. The purpose of this study was to determine a method to increase the desorption efficiency of 16-PAHs using an ultrasonic extraction procedure. Methods: Test samples prepared spiked XAD-2 tubes and PTFE filters in the range of 0.01-1.0 ㎍/mL for desorption efficiency study. Four different extraction solvents, acetonitrile, acetone, tetrahydrofuran and dichloromethane, were tested in order to select the most suitable solvent for the extraction of the 16 PAHs. The addition of dimethyl sulfoxide and sonication time were considered in order to determine the method with the highest extraction efficiency. All samples were made in three sets and analysis was replicated seven times by HPLC. Results: Acetonitrile and acetone were the optimized as an extraction solvent and desorption efficiency of 2-ring PAHs such as naphthalene, acenaphthylene were increased 3~19% with dimethyl sulfoxide for XAD-2. Acetone was the best extraction solvent for PTFE filter and the desorption efficiency was increased 3~13% for 2- to 4-ring PAHs. The optimum sonication time was 60 minutes and desorption efficiency increased with extraction time. Conclusions: As a result, the best extraction solvent was acetone with dimethyl sulfoxide for ultrasonic extraction procedure and the desorption efficiency of this method was better than NIOSH 5506’s. This study could be applied as a method for occupational exposure measurement of PAHs.