• New & Renewable Energy
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• v.3 no.2 s.10
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• pp.31-39
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• 2007

화석연료의 사용으로 인한 자원고갈과 지구온난화 영향 그리고 에너지 안보문제의 해결을 위해 세계 각국들은 대체에너지 개발에 많은 노력을 기울이고 있다. 그 중 수소는 다양한 경로를 통해 생산 가능하고, 수송연료로 사용 시, 유해 물질이 거의 배출되지 않는다는 장점 때문에 가장 주목받는 대체 에너지원이다. 현재는 수소생산 기술개발을 통해 상업화시기를 앞당기려고 하는 수소에너지 시대의 진입시점이라 할 수 있다. 그러나 수소는 생산경로에 따라 다양한 환경성 및 경제성 결과를 도출 할 수 있기 때문에 다양한 평가가 요구된다. 본 연구에서는 국내 수소생산 방식으로 개발/상용화되어있는 Natural Gas Steam Reforming (NGSR), Naphtha Steam Reforming (Naphtha SR), Water Electrolysis (WE)에 대하여, Life Cycle Assessment (LCA)와 Life Cycle Costing Analysis (LCCA) 방법을 사용하여, 수소경로 전반에 대한 즉, 원료채취부터 자동차로 주행하였을 때까지의 각 대상 수소경로의 환경성과 경제성을 평가하였다. LCA와 LCCA 결과는 Naphtha SR과 NGSR 수소경로에서 지구온난화와 화석자원 소모 부문 모두 기존연료 (가솔린, 디젤)와 비교해서 개선효과가 뚜렷하게 나타났으나, WE 수소경로는 오히려 환경부하가 증가되는 것으로 나타났다. 또한 경제성 측면에서는, 수소 판매 시 가솔린과 동일한 연료세율을 부과하더라도 수소가 가솔린에 비해 가격경쟁력을 확보하게 되는데, 이는 주행 시 수소자동차의 연비가 기존 차량에 비해 월등히 좋기 때문에 연료비용의 이점 때문이다. 만약, 수소에 연료세를 부과하지 않는 다면, Naphtha SR로 생산하여 유통한 수소가 수송연료로서 가장 뛰어난 비용효율성을 갖는 것으로 나타났다.

• Resources Recycling
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• v.17 no.3
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• pp.21-28
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• 2008

Using the post-consumer waste and edge scrap mixed PET with small amount PP air filter elements of automobiles. It was studied that these mixed waste plastics of the various types of the PET were practicable for the material recycling. Various waste PET/PP plastics were collected, crushed, dried in vacuum, and extruded to recycled PET/PP chips. These chips were mixed with three kinds compatibilizers, EVA, MBS, and recycled PVB of the ratio of $3{\sim}10wt.%$ for the purpose of the compatibility for the post-consumer waste and edge scrap. We investigated mechanical and thermal properties of PET/PP mixtures which were compound with the weight ratio of compatibilizers. Compatibilizer, MBS application was showed the most excellent mechanical properties in the range of the $3{\sim}5wt.%$ EVA application was displayed good impact strength and thermal property in the range of $3{\sim}5wt.%$ Last, recycled PVB application was showed poor mechanical properties in the whole range ratio of the PVB.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.235-244
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• 2016

Automotive symbols are more widely needed for new, convenient driving devices in automobiles. Good automotive symbols should be detectable, identifiable at first glance, easily learned, recognizable, and produce quick responses after practice. In this paper, a methodology for developing and evaluating automotive symbols is suggested. It includes multiple tests, such as comprehension, perceptual quality, appropriateness, and integrated evaluation. 28 symbols were tested and evaluated by the suggested methodology for convenient driving systems, such as a lane departure warning system (LDWS), cruise control (CCS), and a collision warning system (CWS). Most of the KS R ISO 2575 symbols had higher scores of comprehension, perceptual quality, and appropriateness, but the sunroof and camera symbols had lower scores. Standard symbols with several new functions should be developed. This methodology could be useful for developing and evaluating automotive symbols.

• KIPS Transactions on Computer and Communication Systems
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• v.11 no.8
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• pp.241-248
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• 2022

In this paper, the PID controller and Kalman filter are applied to improve the automobile cruise control in the environment with disturbance and noise, and the performance is verified through diverse simulation. First, a mathematical model for a automobile cruise control system is introduced. Second, the performance degradation due to disturbance in the basic open-loop control based cruise control system is shown and then PID controller-based feedback control system to resolve this problem is verified. Third, to improve the performance degradation due to sensor noise that may occur during the feedback process, a Kalman filter is applied and verified. Ultimately, it is verified that the designed cruise control system with PID controller and Kalman filter not only satisfies all performance conditions but also has the ability for disturbance rejection and noise reduction.

• Korean Journal of Culture and Social Issue
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• v.12 no.4
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• pp.77-99
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• 2006

The purpose of this study was to find out the effects of auto-mobile tinting upon driver's cognitive responses and behaviors through two laboratory experiments, a field experiment and a traffic accident data. The results of two laboratory experiments showed that there were higher false alarm responses under the conditions of 65%, 50%, 35% tinting level than thoses under the 100% level condition. It was also shown that the drivers who had bad sight made more missing responses than the drivers who had normal vision. The main results of the laboratory experiment were repliceted through both the field experiment and the survey research of car accidents. The results of this study were discussed in terms of the previous studies performed abroad. We strongly suggested 70% tinting level as a regulation standard for safe driving and the strategies for implementing the regulation rule.

• Journal of dental hygiene science
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• v.11 no.4
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• pp.311-317
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• 2011

The aim of this analysis was to investigate the relationship between the level of safety behavior and the level of oral health behavior among Korean children. Data used in this analysis were from the 2005 Korean National Health and Nutrition Examination Survey (KNHANES). A representative sample of 4,292 children aged from three to eleven years who completed both health interview and health behavior survey. Simple and multiple logistic regression analyses were conducted. All analyses were weighted and SAS 9.1 survey data analysis procedures were used to estimate standard errors accounting for the complex sampling design of the KNHANES. More than seventy percent of children did not keep general safety behaviors except seat on back seat in a car. About seventy five percent of children had experience of preventive oral care during last one year, but about fifty six percent of children brush their teeth twice a day. Socioeconomic status and health behaviors were significantly related in three to six old age group only (p<.05). Generally significant relationship was not found between general safety and oral health behaviors. Among Korean children, general safety and oral health behaviors might be not related each other. Education for general safety behaviors should be underlined for all children. Especially preschool-children with low socioeconomic status need to be educated for healthy behaviors.

• Journal of the Korean Chemical Society
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• v.62 no.5
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• pp.358-363
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• 2018

The purpose of this study is to show the possibility of using Cu catalyst in removal of $NO_x$ from automobile exhaust which is regarded as the primary source of fine dust PM2.5. The energy and the bond lengths of the three possible structures of Cu-NO complex, which is formed by binding NO molecule to Cu, and the changes in IR and Raman spectra are calculated using MPW1PW91 method on the level of 6-311(+)G(d,p) of basis sets with Gaussian 09 program. As a result, the enthalpy of formation of the Cu-NO complexes are obtained as ${\Delta}H=104.89$, 91.98, -127.48 kJ/mol for the linear, bent, and bridging forms of them, respectively. And the bond lengths between N and O in NO complexes, which becomes longer than NO molecule, indicates that O is easily reduced from Cu-NO. In addition, the Cu-NO complexes using Cu catalyst can be easily measured by infrared or Raman spectroscopy because in the IR and Raman spectra of the NO and Cu-NO complexes the positon and the intensity of bands are definitely different in each vibration mode.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.81-81
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• 2017

본 연구는 전산유체역학(CFD)을 이용하여 트랙터 캐빈 내부의 온도 변화 시뮬레이션 모델을 개발하고 이를 통해 공조장치의 위치를 최적화 하는 것을 목적으로 하였다. 자동차나 열차를 대상으로 시뮬레이션을 이용한 차량 내부의 유동 해석 연구 사례는 많으나, 트랙터를 대상으로 한 연구 사례는 적다. 이에 트랙터의 공조장치를 설계하고 그 성능을 검증할 때 시뮬레이션 모델을 활용한다면, 인력, 시간 등의 손실을 줄일 수 있을 것이다. 본 연구에서는 상용 CFD 프로그램을 활용하여 공조 장치의 위치에 따른 세 가지 트랙터 캐빈 모델을 제작한 뒤, 각각의 모델에 대해서 열 유동 해석을 수행하였다. 시뮬레이션 결과가 실제 트랙터의 시험 결과와 비슷한 경향을 보이고 있음을 확인할 수 있었으며 이를 통해 모델의 적합성을 확인하였다. 또한 세 가지의 캐빈 모델 중 탑승자에게 가장 쾌적한 환경을 제공할 수 있는 모델은 기존의 국내 트랙터와 같은 천정부에 공조 장치가 있는 것이 아니라, 핸들이 있는 전면부에 위치하는 것이 가장 적합하다는 것을 확인할 수 있었다

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2020.07a
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• pp.227-228
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• 2020

어린이 교통관련 안전사고 잠재적 위험요인 및 개선요인을 도출하기 위해 119구조구급자료 중 6세부터 11세까지의 어린이 사고 자료를 분석하였다. 4개 광역지자체의 2014년부터 5년간 자료에 대한 사고내용을 전수 조사하여 분석하였다. 주요 사고 장소 및 시간대 분석 결과 어린이 교통사고는 하교시간 오후 시간대에 도로에서의 집중적 관리가 필요한 것으로 나타났다. 어린이 교통사고 잠재적 위험요인을 분석한 결과 자동차와 자전거를 이외 탈 것에 관한 사고비율이 최근 높아지고 있음을 확인하였다. 연간 교통사고 전체 건수에 대한 추이는 큰 변화는 없었으나 개인 탈것의 사고 증가는 뚜렷하였다. 그 중 킥보드에 대한 사고가 가장 많았고, 퍼스널 모빌리티가 가장 뚜렷한 증가 분야였다. 현재 어린이에게 적용되고 있는 퍼스널 모빌리티 등에 대한 안전가이드라인이나 규정 등은 미비하나 향후 퍼스널 모빌리티의 보급은 크게 늘어날 것으로 전망된다. 향후 어린이 교통사고를 줄이기 위해서는 어린이가 개인 전동 이동수단 활용 시 안전에 대한 규정마련과 교육이 시급하다.

• Journal of the Korea Convergence Society
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• v.8 no.5
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• pp.61-68
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• 2017

This study investigates the differences in medical practices and medical cost according to auto insurance companies based on 8,589,602 cases that were treated by auto insurance corporation for the year of 2015, from the beginning of January to the end of December. The results of this study can be summarized following. First, in terms of the general characteristic in medical treatment, especially the age, the highest figure in both non-life insurance and mutual aid cooperative was shown in the age of 50 to 59 at 22.8 per cent(p<0.001). Second, in terms of a medical cost per a hospital care, classified by clinic, the costs in the department of internal medicine were much higher than those in the surgical department, and the thoracic surgery among parts of the surgical department showed the highest figures in both non-life insurance and mutual aid cooperative. According to the above summarized results of this study, it can be concluded that Health Insurance Review and Assessment Service has to address the problem on the increase of unnecessary costs and the occurrence of social expenses caused by the delay of patients' rehabilitation and return to their daily lives, by carrying out the evaluation for the appropriateness to organizations that ask for payments of auto insurance.