• Journal of Astronomy and Space Sciences
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• v.14 no.2
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• pp.275-285
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• 1997

We have investigated Pi 2 pulsations which were observed both on ground magnetometer array and by satellites. On November 9th in 1994, Pi 2 pulsations appeared globally on the 190/210 magnetometer chain and Hermanus station when two satellites(EXOS-D and ETS-VI) were located near the magnetic meridian of the 210 array. The local time of measurements covers from morning(LT=8.47hr) to afternoon(LT=20.3hr) and the bandwidth of peak frequency is found relatively small. The signals of the electric field are highly coherent with ground-based observations with the out of phase oscillations. However, the magnetic field measurement on the ETS-VI in the outer magnetosphere(L=6.60) shows no signature of Pi 2 pulsations over the same time interval and the correlation with any of the ground-based stations is found to be very weak, even through both satellites and magnetometer chain are located close to each other in local time. We suggest that this event may be a direct evidence of Pi 2 pulsations as virtual resonant modes which are localized in the plasmasphere(Lee 1996). The results show that the cavity mode oscillations can occur in the inner magnetosphere with less spectral noise compared to the outer magnetospheric case.

• Proceedings of the Korean Society of Tobacco Science Conference
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• 1998.10a
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• pp.21-21
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• 1998

• Proceedings of the Korean Society of Tobacco Science Conference
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• 1999.05a
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• pp.16-16
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• 1999

• Proceedings of the Korean Society of Tobacco Science Conference
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• 1997.10a
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• pp.30-78
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• 1997

Exposure of nonsmokers to environmental tobacco smoke (ETS) has been claimed to be associated with an increased risk for lung cancer e. g., in the US, Europe, Japan and several Asian countries. The present paper reports on and discusses the scientific evidence available to date that can be used in order to assess this potential risk for Korea. Evidence related to three key steps in risk assessment, i.e., the characterization of a potential risk, data associating a response to a dose, and data characterizing actual exposures of people to ETS will be reviewed. The final assessment of the potential risk will be left to those qualified and commissioned with the task of risk assessment as a basis for public health policy in Korea.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.19 no.3
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• pp.61-68
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• 2011

유럽연합(EU)은 2012년부터 항공산업에 대해 탄소배출권 거래제도를 적용할 예정이다. 따라서 유럽공항에서 출발 및 도착하는 모든 국제선과 국내선 항공편에 대해 탄소세가 부과될 것이며 이는 한국도 예외는 아니다. 또한 유럽을 운항하는 경우 장거리에 해당되어 중단거리를 운항하는 항공기들에 비해 총 탄소배출량이 더 많으므로 비용부담이 커질 것으로 예상된다. 본 연구는 EU-ETS로 인한 탄소세가 항공요금에 반영된다면 항공여객들이 어느 정도 민감하게 반응할 것이며 이러한 점들이 궁극적으로 한국의 항공시장에 어떤 영향을 미칠 것인지를 파악해 보는데 목적이 있다. 이를 위해 인천국제공항에서 프랑크푸르트 국제공항 노선을 이용하는 승객을 대상으로 직항노선과 중동지역 경유노선을 비교하여 EU-ETS 가격이 반영된 항공요금에 대한 반응을 Revealed Preference (RP)와 Stated Preference (SP) 설문자료와 Logit Model을 사용하여 분석하였다. 본 연구결과는 한국의 항공산업은 물론 2012년부터 부과될 EU-ETS에 대한 항공사들의 전략개발에 도움이 될 것이다.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2004.05a
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• pp.179-184
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• 2004

This paper is an overview of the experimental work using a Planar Magnetic Levitation Stage System structure proposed by Dr. Won-Jong Kim in his PhD thesis. Based on his results, we built an Experimental Test Stand (ETS), which enabled us to get accustomed with the new technology and to create new control structures and algorithms. The ETS is controlled by a powerful controller made of 4 DSPs mastered by a PC. This controller structure increases the controller bandwidth up to 10 kHz leading to a better emulation of an analog controller and leaving enough room for further development. Based on analyzing all the factors that can affect the performances of the system, we achieved a great accurate positioning performance of sub-nanometer RMS value.

• The Korean Journal of Applied Statistics
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• v.35 no.5
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• pp.645-655
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• 2022

In this paper, we investigate automatic functions for time series forecasting in R system and compare their performances. For the exponential smoothing models and ARIMA (autoregressive integrated moving average) models, we focus on the representative time series forecasting functions in R: forecast::ets(), forecast::auto.arima(), smooth::es() and smooth::auto.ssarima(). In order to compare their forecast performances, we use M3-Competiti on data consisting of 3,003 time series and adopt 3 accuracy measures. It is confirmed that each of the four automatic forecasting functions has strengths and weaknesses in the flexibility and convenience for time series modeling, forecasting accuracy, and execution time.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.06a
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• pp.44-45
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• 2020

Korea has the fourth highest CO₂ emission among OECD countries in 2018, As of 2019, total greenhouse gas emissions per capita increased by about 98.2% in comparison to 1990. Korea has promised a 37% reduction in greenhouse gas emissions in 2030 from the projected Paris Climate Change Accord. Currently, many countries use the emissions trading system(ETS) for international carbon management. In 2015, ETS has been implemented in Korea, and the importance of calculating CO₂ emissions from construction machinery has increased. So, we require an accurate calculation of the environmental charges through the allocated CERs. Using the CER price and related search keywords, this paper derive about prediction models of CER price and compare and focus on more accurate prediction about CER price. By this method, the budget needed to establish the initial construction process plan can be calculated based on more accurate predicted CER price.

• Clinical and Experimental Pediatrics
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• v.59 no.8
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• pp.319-327
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• 2016

Allergic diseases such as asthma, allergic rhinitis, atopic dermatitis, and food allergy, are most common chronic, noncommunicable diseases in childhood. In the past few decades, the prevalence has increased abruptly worldwide. There are 2 possible explanations for the rising prevalence of allergic diseases worldwide, that an increased disease-awareness of physician, patient, or caregivers, and an abrupt exposure to unknown hazards. Unfortunately, the underlying mechanisms remain largely unknown. Despite the continuing efforts worldwide, the etiologies and rising prevalence remain unclear. Thus, it is important to identify and control risk factors in the susceptible individual for the best prevention and management. Genetic susceptibility or environments may be a potential background for the development of allergic disease, however they alone cannot explain the rising prevalence worldwide. There is growing evidence that epigenetic change depends on the gene, environment, and their interactions, may induce a long-lasting altered gene expression and the consequent development of allergic diseases. In epigenetic mechanisms, environmental tobacco smoke (ETS) exposure during critical period (i.e., during pregnancy and early life) are considered as a potential cause of the development of childhood allergic diseases. However, the causal relationship is still unclear. This review aimed to highlight the impact of ETS exposure during the perinatal period on the development of childhood allergic diseases and to propose a future research direction.

• Journal of environmental and Sanitary engineering
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• v.17 no.3
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• pp.115-120
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• 2002

This study was performed on a questionnaire survey of 500 people about their awareness for indoor air pollution, and measured efficiency of air cleaner which can remove the CO and air-borne particulate of ETS(Environmental Tobacco Smoke) in air clean chamber. The room-size cleaner for measuring indoor air contaminants has been applied to evaluation of two different air cleaner such as the mechanic air cleaner with hepafilter(HPA) and the electrostatic air cleaner with metal plate. The measuring experiment was carried out in a chamber by sampling the air. The results obtained were as follows; As respondents are having their 90% of daytime indoors a day, and 38% of them can feel indoor air pollutions degrees directly by their sense of smell, For the installation of indoor pollution control equipment, 34% of all respondents installed air cleaner because of the problem of economical charge and almost respondents was not satisfied the trust of ability purified indoor air pollutants. In the experimental results, it was found that more than 95% of CD and air-borne particulate of ETS were removed within 20 minutes. The reaction kinetics of removal pollutants was verified as the pseudo-first order, Finally, it appeared that the room-sire air cleaner can be applied to new technology for removing indoor air contaminants.