• 천문학회보
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• 제42권1호
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• pp.54.3-55
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• 2017

The nature and physical environments of SNRs are diverse, and for this reason, the understanding of the properties of nearby SNRs is useful in interpreting the emission from SNRs in remote galaxies where we cannot resolve them. In this regard, the LMC is a unique place to study SNRs due to its proximity, location, and composition compared with our galaxy. We carried out a multi-wavelength study of SNR N63A in the LMC, a young remnant of the SN explosion of one of the most massive (> 40 Msun) stars in a cluster. It is currently expanding within a large H II region formed by OB stars in the cluster and engulfing a molecular cloud (MC). As such, N63A is a prototypical SNR showing the impact of SN explosion on the cluster and its environment. Its morphology varies strongly across the wave bands, e.g. the size in X-ray is three times larger than in optical. However, the bright optical nebula would correspond to a MC swept up by the SNR, and consequently the interaction SNR-MC is limited to the central portion of the SNR. We aimed to study the overall structure of N63A, using near-IR imaging and spectroscopic observations to obtain the physical parameters of the atomic shocks, and also to understand how the SNR- MC interaction works and reveal the structure of the shocked cloud as well as the consequences of the impact of the SNR shock on the MC, comparing information obtained in different wavelengths.

• 환경영향평가
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• 제18권6호
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• pp.347-357
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• 2009

This study conducted a vulnerability assessment on Korea's physical infrastructure to provide base data for developing strategies to strengthen Korea's ability to adapt to climate change. The assessment was conducted by surveying professionals in the field of infrastructure and climate change science. A vulnerability assessment was carried out for seven climate change events: average temperature increases, sea level rise, typhoons and storm surges, floods and heavy rain, drought, severe cold, and heat waves. The survey asked respondents questions with respect to the consequences of each climate change event, the urgency of adaptation to climate change, and the scale of investment for adaptation to each climate change event. Thereafter, management priorities for infrastructure were devised and implications for policy development were suggested. The results showed that respondents expected the possibility of "typhoons and storm surges" and "floods and heavy rain" to be the most high. Respondents indicated that infrastructure related to water, transportation, and the built environment were more vulnerable to climate change. The most vulnerable facilities included river related facilities such as dams and riverbanks in the "water" category and seaports and roads in the "transport and communication" category. The results found were consistent with the history of natural disasters in Korea.

• 국제물리치료학회지
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• 제9권1호
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• pp.1406-1412
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• 2018

This study aimed to measure the grip strength of the dominant and non dominant hands of right-handed normal adults in the supination, pronation, and neutral positions of the forearms. The subjects of this study were instructed to make the standard posture suggested by the American Society of Hand Therapists (ASHT) in order to minimize the impact of changes in the posture of the body as follows. The grips strength was statistically different between groups (p<.05). In the follow up test using Scheffe test, the grips in the neutral position and supinator position did not show any difference, while the grip in the pronation was smaller than those of the above two other positions. The grips of the mainly used forearm and non-mainly used forearm of the study target did not show any statistically significant difference in the neutral, supinator and pronation positions of the forearm. This study is expected to provide basic information for studying the impact of the positions of the forearms on grip strength, assessing the prehensility of patients in clinical settings, and setting therapeutic goals.

• 한국음향학회지
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• 제15권4호
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• pp.12-17
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• 1996

최근 각종 교통소음 공해의 심각성과 주민들의 생활의 질에 대한 요구는 나날이 높아 가는 추세이다. 따라서 소음영향평가 및 소음조절 방안수립에 대한 연구의 필요성이 절실히 요구된다. 본 연구에서는 문헌고찰 및 실측을 통하여 선진 외국의 고속열차에 대한 소음의 물리적 특성을 규명한 후, 국내에서 최초로 건설되는 고속철도 전용역사인 C 종합역사를 대상으로 외부환경 소음도를 평가하였다. 이는 향후 국내 고속철도 개통에 따른 소음영향의 제반 문제점 및 개선방향과 역사 건물 실내외의 소음방지 대책을 수립하는데 주요 기초 자료로 활용될 수 있을 것으로 판단된다.

• 대한치과의사협회지
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• 제49권10호
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• pp.584-598
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• 2011

The age structure has been experiencing substantial change due to the decreased birth rate as well as the increased life expectancy. Gorge Magnus, an English economist, casts warnings of population ageing which has the potential of huge socioeconomic impact human society has never experienced before. The prediction that proportion of elderly people in need of oral health care will increase substantially is a new challenge to dentists in the future. The old paradigm that the aged person is just the person who was born earlier and needs the same conventional oral health care should be shifted to the new one. Elderly people tend to express their political interest related with health care system by actively participating in the national elections. The need to sustain economic status for the extended life span makes them seek eagerly esthetic health care to maintain sound social function. Most of them are under multiple chronic diseases and take related medicines. In addition, many studies report about mental change as well as physical change among the aged people. Since the prevalence of dental diseases among the aged is higher than other chronic devastating diseases, the aged seeking oral health care will increase. The aged who has different physical and psychological status as well as chronic disease and related medicine will show unexpected response to the conventional oral health care. In addition, the impact of tooth loss is substantial physically, mentally and emotionally. Dentist should prepare different approaches for the elderly dental patient.

• 한국기계가공학회지
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• 제19권10호
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• pp.59-67
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• 2020

Polycarbonate thermoplastic composite materials are anisotropic and exhibit physical properties in the longitudinal direction. Therefore, the physical properties depend on the type and direction of reinforcements. The thermal conductivity, electrical conductivity, and resin impregnation can be controlled by adding carbon nanotubes to polycarbonate resin. However, the carbon fiber used as a reinforcing material is expensive, interfacial adhesion issues occur, and simulation values are different from actual values, making it difficult to perform mathematical analysis. However, carbon nanotubes have advantages such as light weight, rigidity, impact resistance, and reduced number of parts compared to metals. Due to these advantages, it has been applied to various products to reduce weight, improve corrosion resistance, and increase impact durability. As the content of carbon nanotubes or carbon fibers increases, the mechanical properties and antistatic and electromagnetic shielding performance improve. It is expected that the amount of carbon nanotubes or carbon fibers can be optimized and applied to various industrial products.

• Asian Journal of Innovation and Policy
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• 제11권1호
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• pp.110-147
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• 2022

Many megacities are exposed to natural hazards such as earthquakes, and when located in coastal regions, are also vulnerable to hurricanes and tsunamis. The physical infrastructures of transportation systems in megacities have become so complicated that very few organizations can understand their response to extreme events such as earthquakes and can effectively mitigate subsequent economic downfalls. The technological advances made in recent years to support these complex systems have not grown as fast as the rapid demand on these systems burdened by population shift toward megacities. The objective of this paper is to examine the risks imposed on and recoveries of transportation systems in megacities as the result of extreme events such as an earthquake. First, the physical damage to transportation infrastructure, loss of the transportation system performance, and the corresponding economic loss from disruptions to passenger and freight traffic is evaluated. Then, traffic flows are re-routed to reduce vehicles' delay due to earthquakes using a microscopic traffic flow simulator with an optimization model and macroscopic terminal simulator. Finally, the economic impact of the earthquake is estimated nationwide. Southern California is regarded as the region of study. The results demonstrate the effectiveness of the integrated model and provide what and how to prepare innovative resilience policies of urban infrastructure for a natural disaster occurrence.

• 한국콘텐츠학회논문지
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• 제10권8호
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• pp.407-416
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• 2010

이 연구의 목적은 생활무용 참가가 여성의 신체이미지 및 자아존중감의 관계를 규명하는데 있다. 이를 위하여 2009년 서울 경기도지역에 있는 스포츠센터, 일반동호회, 지역동호회, 댄스학원, 일반인을 대상으로 생활무용에 참여하고 있는 20~50대 성인여성을 모집단으로 설정한 다음, 유의표집법을 이용하여 300명을 추출 하였다. 설문지의 신뢰도는 분석결과 Cronbach's $\alpha$ 값이 .70이상으로 나타났다. 이 연구에서 사용한 주요통계기법은 빈도분석, 신뢰도 요인분석, 공변량분석, 회귀분석 및 경로분석이다. 이상과 같은 연구방법 및 절차를 통해 도출된 결론은 다음과 같다. 첫째, 생활무용 참가여성은 비참가여성에 비해 신체이미지 및 자아존중감을 더 긍정적으로 평가한다. 둘째, 생활무용 참가기간은 체형, 만족, 유연성요인에 영향을 미치고 있으며, 참가강도는 체형과 근력요인에 영향을 미친다. 셋째, 생활무용참가기간은 자아존중감에 영향을 미치며, 참가빈도는 부적 영향을 미치는 것으로 나타났다. 넷째, 여성의 생활무용 참가정도는 신체 이미지 그리고 자아존중감에 인과적 영향을 미친다. 즉 생활무용 활동 정도는 자아존중감에 직접적인 영향을 미칠 뿐만 아니라, 신체이미지 변수를 통하여 자아존중감에 간접적인 영향을 미친다. 이러한 결과에서 보듯이 신체이미지는 생활무용 참가와 자아존중감을 연결해주는 중요한 매개변수 역할을 한다.

• 한국치위생학회지
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• 제10권5호
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• pp.877-885
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• 2010

Objectives : This study was carried out with the aim of utilizing it as basic data in a plan for oral health promotion by analyzing oral-health awareness in high school students of some districts in our country, and by analyzing physical, mental and social influential factors in oral health, through using OHIP(Oral Health Impact Profile). Methods : It surveyed by carrying out self-administered questionnaire research targeting 536 boy & girl high school students in the 1st and the 2nd grade at 3 high schools in some districts of Gyeonggi Province. Results : 1. As for experience of having not visited dental clinic, a case of having not visited accounted for 32.5%. On the other hand, a case of having visited accounted for 67.5%. As for the appearance of oral health education, only 2.8% responded as saying of having experience. 97.2% responded as saying of having not taken oral health education. 2. As for oral health state perceived by oneself, the response as saying of 'thinking it to be healthy' and that 'there is something wrong' showed the distribution of 34.1% that is the same ratio. As for oral health interest, a case of having a little interest(58.4%) or of being so much interested(12.5%) showed 70.9%. A case of having no special interest(24.8%) or of having no interest at all(4.3%) showed the level of 29.1%.3. As for oral health knowledge, the toothbrushing knowledge was the highest with 4.54 marks out of 6-point perfection. The toothbrush knowledge(4-point perfection) showed low point with 2.05 marks. 4. By gender, a case of men was high in OHIP(Oral Health Impact Profile) for the functional restriction and physical pain. On the other hand, in the remaining sphere, women were indicated to be high in OHIP. The statistically significant difference was indicated in the spheres such as physical pain, psychological discomfort, a drop in psychological ability, a drop in social ability, and social separation. 5. According to oral health state perceived by oneself, a case of thinking it to be healthy was indicated to be high in OHIP for every sphere. A case of thinking it to have gum disease was indicated to be low in OHIP for every sphere. The statistically significant difference was indicated in every sphere except the sphere of functional restriction. 6. As for a factor of having influence upon OHIP according to oral health knowledge, it was indicated that the higher toothbrush knowledge leads to having more influence upon OHIP. Conclusions : It could be known that the oral health knowledge and OHIP are varied as well according to the oral health interest level. Also, the oral health education proper for subjects is not being performed. Even as for frequency of visiting the dentist, a regular visit is failing to be made. In consideration of these points, the diversified and effective educational program is likely considered to be necessarily developed and improved that subjects can have more interest in oral health.

• 접착 및 계면
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• 제16권3호
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• pp.101-107
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• 2015

코어/쉘 나노입자, CTBN 변성에폭시, 폴리에스터 폴리올, 폴리우레탄 등과 같은 다양한 종류의 강인화 소재는 에폭시 수지의 주요 단점으로 알려진 취성을 보완하여 낮은 충격 저항성을 개선시키기 위한 방법으로 연구되고 있다. 본 연구에서는 앞서 언급된 강인화 소재를 선정, 접착제 조성물에 첨가하여 기계적 물성을 조사하였다. 강인화 소재 도입에 따른 기계적 강도의 측정은 UTM을 이용한 굴곡 강도와 탄성률 측정 및 Izod 충격 시험기를 사용한 충격 강도 실험을 통해 이루어 졌으며, 그 결과 강인화 소재가 에폭시 경화물의 유연성 및 충격에 대한 저항성 향상에 미치는 긍정적인 효과가 나타남을 관찰하였다. 또한, DMA를 이용한 저장 탄성률 결과는 굴곡 탄성률의 결과와 동일한 경향으로 나타남을 확인하였다. 강인화 소재가 충격 강도 향상에 영향을 주는 이유는 에폭시 수지에 첨가된 강인화 소재의 상 분리 현상에 의한 것이며, 상 분리된 강인화 소재는 에폭시 조성물의 파단면을 관찰한 FE-SEM 이미지에서 관찰하였다.