• Journal of the Korean Association of Geographic Information Studies
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• v.13 no.4
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• pp.91-100
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• 2010

Existing traffic safety studies have focused on identifying the relationship among roadway crashes, highway design and incremental weather condition such as rainy/ice weather. However, it is hard to find researches that studied the effect of sun glare on traffic safety although there are abundant evidences demonstrating that fatal traffic crashes are attributed to the sun glare. Affecting drivers'vision particularly during the morning or the evening time when the sun positions close to the horizon, sun glare directly deteriorate drivers'judgmental capability. In this paper, we numerically analyze the effect of sun glare on the drivers'vision in time and space domains. Applied to the roadways around St Louis area in the United States, the GIS based simulation analysis identifies the time of day in a year and the segments of highways that are potentially influenced by the sun glare. This study evidentially confirms the fact that roadway bounded for West and East directions have longer time influenced by sun glare particularly during Spring and Fall season than other roadways. The computational result provides risky time periods of day at intersections or pedestrian crossings where the sun glare potentially endangers traffic safety, which be utilized to reduce the crashes due to the sun glare.

• The Journal of the Acoustical Society of Korea
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• v.21 no.8
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• pp.708-718
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• 2002

In this paper, the problems in identifying the noise sources by using the sound intensity technique are dealt with for the general radiated near-field from vibro-acoustic sources. For this purpose, a three-dimensional model structure resembling the engine room of a car or heavy equipment is considered. Similar to the practical situations, the model contains many mutually coherent and incoherent noise sources distributed on the complicated surfaces. The sources are located on the narrow, connected, reflecting planes constructed with rigid boxes, of which a small clearance exists between the whole box structure and the reflecting bottom. The acoustic boundary element method is employed to calculate the acoustic intensity at the near-field surfaces and interior spaces. The effects of relative source phases, frequencies, and locations are investigated, from which the results are illustrated by the contour map, vector plot, and energy streamlines. It is clearly observed that the application of sound intensity technique to the reactive or reverberant field, e.g., scanning over the upper engine room as is usually practiced, can yield the detection of fake sources. For the precise result for such a field, the field reactivity should be checked a priori and the proper effort should be directed to reduce or improve the reactivity of sound field.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.3
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• pp.72-82
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• 2013

This study was done for analyzing processes on the planning and opening of chronological urban parks in Daegu City since the 1960s, and for interpreting the social meaning on changes of the urban parks with regards to historical circumstances during that period. In the 1960s, urban parks, which were recognized as one of urban planning facilities, were only designated for creating rather than created, although nationally several laws including urban planning act and park act were newly legislated. Rapid urbanization and increasing population in the 1970s led to create many urban parks. However, the policy for increasing parks had been not successful because of the lack of enough funds. In the 1980s, multi-purpose urban parks including stable area as well as active facilities were created for getting several attractions to urban residents. During this period, urban parks were recognized on an aesthetic perspective through vegetating plans on the city-beautiful movement for hosting consecutive international games. The citizen participation in urban parks and the increasing concern about urban environment were started in the 1990s, and the people living in an urban area were interested in the quantitative expansion and qualified renovation of the urban parks as well. Finally, modernistic urban parks were first introduced in the late period of Chosun Dynasty, however their substantial introduction was done in the 1960s. Through this study, the concept of an urban park as a public resting place for citizen in Daegu was thought to be mostly established in the 1990s as we have investigated on the social meaning derived from the periodical changes of urban parks.

• Journal of the Korean Regional Science Association
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• v.33 no.3
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• pp.31-47
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• 2017

The purpose of this study is to identify determinants of economic aid regarding housing and cost of living for the newly-married households. This study applied the binary logit model to figure out the determinants of economic aid from their parents for the households. With utilizing the Newly-Married Housing Survey data in 2015, this study found that housing characteristics and level of housing expenditure leads to the economic aid from their parents. In particular, the housing price and transportation condition increase probability the financial aid from parents when the newly-married household starts their housing career. In addition, this study found that the items of housing expenditure increase the probability of economic aid for their cost of living. To improve the independence of newly-married household, the government should adopt the housing policy for stable housing price and alleviate the burden of housing expenditure. The significance of this study is analyzing the economic aid from their parents on newly-married household regarding housing economic issues and suggest the policy for independence of living from their parents.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.6
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• pp.103-108
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• 2016

The size of urban areas is currently growing and the functions of cities are becoming increasingly complicated. Furthermore, more people are living in cities. The life of urban is getting closer and linked with neighboring people in many parts. In particular, people are making artificial noise, even though it might not consciously be noticed, in their daily live. Seoul is the most crowded place in Korea and the noise levels are 73dB or higher. People living in cities are exposed to noise pollution. In particular, loudspeakers used during demonstrations or to generate publicity, cause considerable noise, which in turn can be related to stress. Moreover, the noise restrictions defined by law are not adhered to. If enhanced noise regulations, no matter how residents are not forced to be a great stress field close to the noise and reduces the loudness -5dB do not feel well if the difference. Limiting the duration of noise rather than reducing the volume thus is a much more plausible way of reducing the damage caused by noise pollution. If the stress caused by the noise, you will see people or vehicles holding a megaphone at the roadside is not good for health if it may be a wise way to live that is getting rid of the noise pollution so quickly out of the area.

• Korean Journal of Remote Sensing
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• v.35 no.6_3
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• pp.1285-1298
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• 2019

Drought is one of the factors that can cause wildfires. Drought is related to not only the occurrence of wildfires but also their frequency, extent and severity. In South Korea, most wildfires occur in dry seasons (i.e. spring and autumn), which are highly correlated to drought events. In this study, we examined the relationship between wildfire occurrence and drought factors, and developed satellite-based new drought indices for assessing wildfire risk over South Korea. Drought factors used in this study were high-resolution downscaled soil moisture, Normalized Different Water Index (NDWI), Normalized Multi-band Drought Index (NMDI), Normalized Different Drought Index (NDDI), Temperature Condition Index (TCI), Precipitation Condition Index (PCI) and Vegetation Condition Index (VCI). Drought indices were then proposed through weighted linear combination and one-class support vector machine (One-class SVM) using the drought factors. We found that most drought factors, in particular, soil moisture, NDWI, and PCI were linked well to wildfire occurrence. The validation results using wildfire cases in 2018 showed that all five linear combinations produced consistently good performance (> 88% in occurrence match). In particular, the combination of soil moisture and NDWI, and the combination of soil moisture, NDWI, and precipitation were found to be appropriate for representing wildfire risk.

• Information Systems Review
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• v.15 no.3
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• pp.111-128
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• 2013

Conventions play important roles as tools for effective marketing. It will be able to understand the changes of particular industry's market, develop a new market and potential clients, and get a chance such as strategic network constructing. To support effective viewing of visitors, conventions have introduced a variety of ubiquitous computing technologies. This study introduces a case of applying the Utility Tag-based convention service system at the Cosmetics & Beauty Expo, Osong Korea 2013. The Utility Tag-based convention service system is constructed total three systems: (1) NFC Tag Management System; allowing effective access and management of NFC tags in various locations and objects, (2) Information Provide System; allowing participating vendors to manage information they want to provide information to visitors, and (3) Utility Tags; providing a variety of service to visitors for effective viewing in exhibition/convention space. This study first explores literature review and applying case related to ubiquitous computing in this field and introduces Applying an Utility Tag-based convention service system. In addition, we analyze visitors' behaviors and association rules by take advantage of collected touch data, present various possible for applications of the Utility Tag-based convention service system.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2000.04a
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• pp.4-4
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• 2000

일반적인 액체추진제 로켓엔진의 연소는 분사제트의 미립화, 액적의 증발, 기상 추진제의 혼합, 화학반응 등, 일련의 물리적 과정들로 이루어지고, 여기서 특성속도 효율은 크게 분사특성 및 연소의 두 단계에서 결정되게 된다. 액체추진제 로켓엔진에 사용되는 여러 분무형태 중, 동축형 분사기에서는 액상과 기상 제트의 운동량 차에 의해 미립화가 이루어지며, 분무 액적들의 전개와 더불어 분사기 출구를 포함한 전 영역에서 연소가 발생되므로 매우 복잡한 물리적 특성들을 포함하게 된다. 본 연구에서는 기상 연료-액상 산화제의 동축형 분무연소를 JANNAF의 방법을 사용하여 수식화 하였으며, 이를 바탕으로 분무특성과 연소성능 예측을 위한 프로그램을 작성, 분사조건에 의한 분무특성과 그에 따른 연소성능을 계산하였다. 연속, 운동량, 에너지 및 혼합비 방정식의 지배방정식들을 바탕으로 기상 유동을 수식화 하였으며, 별도로 액적의 소산 및 연소과정을 모사하기 위한 별도의 수식들이 추가되었고, 이 식들을 결합하여 액적의 크기, 분포를 포함하는 액체 제트의 미립화 정도를 공간적으로 계산하였다. 미립화 모델의 검증을 위하여 계산 결과를 Reitz의 실험과 Giridharan의 모델 등과 비교하였으며 잘 일치하는 경향을 나타내었다. 또한 동축형 분사기에서의 분무 특성을 예측하기 위해 액체 산소, 기체 수소를 추진제 조합으로 하는 동축형 분무 연소장에서의 제트 길이, 액적의 크기, 액체 제트의 속도를 계산하였다. 계산 결과 액체 제트의 접촉길이는 분사공의 지름이 증가할수록 웨버수가 증가되므로 짧아지는 것으로 관찰되었으며 액적의 크기도 분사공의 지름이 증가할수록 작아지는 경향을 나타내었다. 액체 제트의 속도는 처음에는 일정하게 유지되다가 운동량을 보존하기 위해 가스로부터 운동량을 받아 점차 가속되어지는 것으로 나타났다.본 규격은 키, 총장, 어깨길이, 등길이, 머리길이, 머리둘레, 진동둘레, 목둘레, 가슴둘레, 허리둘레, 배둘레, 엉덩이둘레, 앞품, 뒤품, drop치를 포함하고 있고, 각 규격에서 호칭간 치수 간격도 함께 제시하고 있다. 본 연구 결과에서 보듯, 현행 8규격의 무진복의 각 호칭간 적정 허용범위를 고려해 합리적인 치수체계를 정립한다면 치수에 대한 적합도가 상당히 증가할 뿐 아니라 생산비용도 상당히 감축할 것으로 생각된다.나타났다. 4) 호감적 서비스능력 차원에서 세 독립변수간에 유의한 3원 상호작용이 존재하는 것으로 나타나( $F_{2,228}$=15.62, P<.001) 20대에 적합한 의복 착용시( $F_{2,228}$=3.98, P<.05)와 60대에 적합한 의복 착용시( $F_{2,228}$=16.55, P<.001) 점포유형과 격식차림간에는 유의한 상호작용이 존재하는 것으로 나타났다. 5) 호감을 구성하는 세 요인들이 구매의도에 미치는 영향을 조사한 결과 호감적 인상차원은 29%(P<.001), 호감적 서비스능력차원은 6%(P<.001)의 구매의도를 설명해 주는 것으로 나타났다. 본 연구결과 노년 소비자에게 호감을 주는 판매원의 외모는 구매의도에 영향을 주어 실버의류산업의 이익증대와 밀접한 연관을 갖는 서비스품질의 중요한 요인으로 밝혀졌다.중요한 요인으로 밝혀졌다.로운 단백질 EPSPS가 다른 여러 식물에 이미 존재하고 있는 단백질로서 우리가 이미 이러한 식품을 섭취할 때 이 단백질도 같이 섭취해오고 있었다는 점, 둘째. 이 단백질이 소화액 분해 실험에서 짧은 시간내에 분해가 되었다는 점, 셋째. 재조합 된 콩과 자연 콩이 성분 분석에서 차이를 나타내지 않았다는 점, 네 번째. 쥐를 통한 다양섭취 실험에서 아무런 이상 반응이 없었

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.1
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• pp.1-6
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• 2000

Dentinogenesis imperfecta is an inherited disorder of dentin formation, usually exhibiting an autosomal dominant mode of transmission. Type I dentinogenesis imperfecta occurs in patients afflicted with osteogenesis imperfecta. Type II dentinogenesis imperfecta is not associated with osteogenesis imperfecta. Type III dentinogenesis imperfecta (Brandywine type) occurs in a racial isolate area in the state of Maryland. In all three types, teeth of both dentitions are affected with variable clinical appearances. The teeth are opalescent with the color ranging from bluish-gray to brown to yellowish. The dentin is abnormally soft, providing inadequate functional support to the overlying enamel. Although the enamel is normal, it fractures or chips away easily, exposing the occlusal and incisal dentin. The exposed soft dentin often undergoes rapid and severe functional attrition. The teeth exhibit bulb-shaped crowns with constricted cementoenamel junctions and thin roots. The teeth will exhibit varying stages of obliteration of the coronal and root pulpal chambers. The cementum, periodontal ligament and supporting alveolar bone appear normal. The enamel is normal. The mantle dentin remains nearly normal, whereas the remaining dentin is severely dysplastic. The dentinal tubules are disoriented, irregular, widely spaced, and usually larger than normal.

• Journal of the Korean Society for Library and Information Science
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• v.39 no.3
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• pp.105-119
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• 2005

With the introduction of Internet-based education such as online learning and virtual campuses. there are increased interests and demands for electronically delivering educational contents in comparison to the traditional educational methods. Our preilminary study showed that approximately $50\%$ of virtual groups formed online for the scope of collaborative learning encountered harriers that prevented them from forming an effective learning team and making satisfactory progress toward reaching the learning objectives. In this study, we asked the undergraduate students. who were the members of the online learning team, to work on the given discussion topics through the use of emails and threaded discussion boards. Then. we investigated the roles played by two electronic communication medium during the virtual discussion with respect to the learning outcome. We also studied how information was shared amongst the virtual learning team members. The results of our study showed that the email based online learning had the advantage of individualized and friendly information transfer. However. it also caused certain difficulty in exchanging ideas due to the one-sided nature of the email-based communication. On the other hand, the threaded discussion board provided easier information sharing and broadcasting. which enabled active participation by the virtual team members. However. It also had the disadvantage of difficulty in accurate information conveyance and duplication of the posted information. In summary, our study results showed that there was a high correlation between the characteristics of the electronic communication medium and the decision that the online learners made regarding which medium to use. There was a high correlation between the type of the electronic communication medium and the online learners' experiences in using these media.