• Journal of Astronomy and Space Sciences
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• 제21권2호
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• pp.93-100
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• 2004

We have investigated characteristic solar wind dynamics associated with relativistic electron events at geosynchronous orbit. Most of the events for April, 1999 through December, 2002 are found to be accompanied by a prolonged solar quiet period which is characterized as low solar wind density, weak interplanetary magnetic field (IMF), and fast alfvenic fluctuations in IMF $B_z$. In a typical relativistic event, electron fluxes begin to increase by orders of magnitude when solar wind parameters drop to low values (e.g., $n_{sw}∼5 cm^{-3}$ and ｜$B_{IMF}$∼5 nT) after sharp peaks. Then the elevated electron fluxes stay at the high level during the solar quiet period. This observation may suggest the following scenario for the occurrence of a geosynchronous relativistic event: (ⅰ) Quiet solar winds can yield a stable and more dipole-like magnetospheric configurations in which the geosynchronous orbit locates well inside the trapping boundary of the energetic electrons. (ⅱ) If a large population of MeV electrons are generated (by whatever acceleration process(es)) in the inner magnetosphere, they can be trapped and effectively accumulated to a high intensity. (ⅲ) The high electron flux can persist for a number of days in the geosynchronous region as long as the solar wind dynamics stays quiet. Therefore the scenario indicates that the occurrence of a relativistic event would be a result of a delicate balance between the effects of electron acceleration and loss. In addition, the sensitive dependence of a relativistic event on the solar wind conditions makes the prediction of solar wind variability as important as understanding of electron acceleration processes in the forecast of a relativistic event.

• Journal of Korean Medical Science
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• 제33권49호
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• pp.314.1-314.15
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• 2018

Background: Despite its growing significance, studies on the burden of disease associated with natural disasters from the perspective of public health were few. This study aimed at estimating the national burden of disease associated with typhoons and torrential rains in Korea. Methods: During the period of 2002-2012, 11 typhoons and five torrential rains were selected. Mortality and morbidities were defined as accentual death, injury and injury-related infection, and mental health. Their incidences were estimated from National Health Insurance Service. Case-crossover design was used to define the disaster-related excess mortality and morbidity. Disability-adjusted life years (DALYs) were directly assessed from excess mortality and morbidity. Results: The burden of disease from typhoons increased with the intensity, with 107.7, 30.6, and 36.6 DALYs per 100,000 per event for strong, moderate, and weak typhoons, respectively. Burden of disease from torrential rains were 56.9, 52.8, and 26.4 DALYs per 100,000 per event for strong, moderate, and weak episodes, respectively. Mental disorders contributed more years lived with disability (YLDs) than did injuries in most cases, but the injury-induced YLDs associated with strong typhoon and torrential rain were higher than those of lower-intensity. The elderly was the most vulnerable to most types of disaster and storm intensities, and males younger than 65 years were more vulnerable to a strong torrential rain event. Conclusion: The intensity of torrential rain or typhoon was the strongest determinant of the burden of disease from natural disasters in Korea. Population vulnerable may vary depending on the nature and strength of the disasters.

• 한국언어정보학회지:언어와정보
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• 제18권2호
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• pp.141-168
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• 2014

Recognizing spatial information associated with events expressed in natural language text is essential not only for the interpretation of such events and but also for the understanding of the relations among them. However, spatial information is rarely mentioned as compared to events and the association between event and spatial expressions is also highly implicit in a text. This would make it difficult to automate the extraction of spatial information associated with events from the text. In this paper, we give a linguistic analysis of how spatial expressions are associated with event expressions in a text. We first present issues in annotating narrative texts with reference relations between event and spatial expressions, and then discuss surface-level linguistic characteristics of such relations based on the annotated corpus to give a helpful insight into developing an automated recognition method.

• 천문학회보
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• 제44권1호
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• pp.73.4-73.4
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• 2019

The TXS0506+056 is a blazar and counterpart of the neutrino event IceCube-170922A. It is the first time that the neutrino event and flaring event in electromagnetic wave (EM) coincided. We observed TXS0506+056 with medium-bands in optical using 0.25m and 2.1m telescope at McDonald observatory about a month after the neutrino event. We tracked the variability of SED of the target for three weeks, and our observation showed no abrupt variability in optical range during this period. We concluded that a month after the neutrino event, the TXS0506+056 became less active and shows no feature of the energetic event. We also concluded that the medium-bands are well suited for tracking SEDs of objects. Our result demonstrates the potential of the wide-field 0.25m telescope (5.5 deg^2) for finding transient objects and track the variability of sources like AGNs.

• 한국정보통신설비학회:학술대회논문집
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• 한국정보통신설비학회 2009년도 정보통신설비 학술대회
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• pp.157-161
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• 2009

In recent years, there is a remarkable progress in ICTs (Information and Communication Technologies), and then many attempts to apply ICTs to other industries are being made. In the field of disaster managements, ICTs such as RFID (Radio Frequency IDentification) and USN (Ubiquitous Sensor Network) are used to provide safe environments. Actually, various types of early warning systems using USN are now widely used to monitor natural disasters such as floods, landslides and earthquakes, and also to detect human-caused disasters such as fires, explosions and collapses. These early warning systems issue alarms rapidly when a disaster is detected or an event exceeds prescribed thresholds, and furthermore deliver alarm messages to disaster managers and citizens. In general, these systems consist of a number of various sensors and measure real-time stream data, which requires an efficient and rapid data processing technique. In this study, an event-driven architecture (EDA) is presented to collect event effectively and to provide an alert rapidly. A publish/subscribe event processing method to process simple event is introduced. Additionally, a complex event processing (CEP) technique is introduced to process complex data from various sensors and to provide prompt and reasonable decision supports when many disasters happen simultaneously. A basic concept of CEP technique is presented and the advantages of the technique in disaster management are also discussed. Then, how the main processing methods of CEP such as aggregation, correlation, and filtering can be applied to disaster management is considered. Finally, an example of flood forecasting and early alarm system in which CEP is incorporated is presented It is found that the CEP based on the EDA will provide an efficient early warning method when disaster happens.

• 한국지능시스템학회논문지
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• 제7권1호
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• pp.5-15
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• 1997

This paper mentions a fault tree analysis using not probability but natural language and fuzzy theory, Reliability estimate of each basic event and dependence level estimate among subsystems are expressed by linguistic terms. Analysis results are also expressed by natural language. The meaning of linguistic terms is expressed by a fuzzy set. In the presented analysis approach parametrized operations of fuzzy sets are considered so that analyst's subjectivity can be introduced into the analysis. This paper gives the Chernobyl accident as an example of the fuzzy fault tree analysis using linguistic terms.

• 한국화재소방학회논문지
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• 제17권1호
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• pp.8-20
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• 2003

천연가스는 서울에서 새로운 도시가스로서 지하배관망루 벨브스테이션을 통하여 공급되어 왔다. 그러나 천연가스는 편리함과는 대조적으로 운송시스템의 오류 또는 부주위한 취급으로부터 화재 및 폭발을 야기할 수 있는 매우 실제적인 잠재위험성을 가지고 있다. 따라서 이 연구의 주요 목적은 전형적인 배관망을 구성하는 공급설비의 신뢰성을 평가한 후 주요 잠재위험성의 확인 및 위험성평가를 수행하는 것이다. 본 연구에서는 Fault Tree Analysis와 Event free Analysis에 의해 서울의 임의의 지점 두 곳을 설정하여 최종적인 단계(top event)로서 밸브기지의 소규모 누출과 대규모 누출, 각 도시가스회사로의 천연가스공급중단을 설정하여 각각에 대한 발생빈도의 값을 알아보았다. 그 결과 소규모 누출시 DC, DS 밸브기지에 대하여 각각 3.29, 1.41의 값으로 나타났으며, 대규모 누출에 대하여는 1.90$\times$$10^{-2}$, 2.32$\times$$10^{-2}$, 또한 도시가스회사로의 천연가스공급중단에 대한 각각의 기지에 대한 수치는 2.33$\times$$10^{-2}$, 2.89$\times$$10^{-2}$로 나타났다. 또한 단위 지역 공급설비에 대한 전체적인 신뢰도와 기기별 신뢰도의 계산함으로서 기기와 공급망간의 상호관계성의 인식과, 전체 설비 굽에서 중요한 부분과 좀더 강조되어야 할 부분을 찾아내기 위해 Minimal Cut Set 방법을 사용한 결과, DC 밸브기지의 경우, 기기단위별로는 6, 7, 26, 27 등이 취약함을 보여주고 있으며, 또한 basic event 26, 27의 조합으로 인한 천연가스공급중단의 위험이 가장 크므로 이 부분에 대해서 하나의 라인이 병렬로 추가되어야만 좀더 안정적이고 위험부담이 적은 시스템으로 운영할 수 있다. 이러한 경우 공급중단의 고장율이 1/4로 줄어드는 효과를 가지게 된다. DS 밸브기지의 경우, basic event 4가 천연가스공급중단의 원인의 92%를 차지하고 있다. 그러므로 이 부분의 portion을 낮춰준다면 전체의 고장율도 낮춰질 수가 있고 이 부분에 같은 종류의 라인을 추가로 설치하면 고장율이 약 1/10로 줄어드는 효과를 보게 된다. 또한 기기단위별로는 6, 7, 26, 27 등이 가장 취약한 것으로 나타났다. 이 부분에 대해서는 안전장치나 설비를 추가로 갖추거나, 혹은 점검기간의 주기를 줄이도록 하는 것이 필요하다. 향후 본 연구에서 다루어진 신뢰도 측정방법을 각 공급설비에 대해 적용한다면 좀 더 효율적으로 공급설비의 신뢰도를 계산, 분석할 수 있고, 천연가스공급설비의 안전성 향상에 도움이 될 것으로 기대된다.

• 한국언어정보학회:학술대회논문집
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• 한국언어정보학회 2007년도 정기학술대회
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• pp.202-209
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• 2007

Compound verbs in Korean show properties of both syntactic phrases and lexical items. Earlier studies of compound verbs have either assumed two homonymous types, i.e. one as a syntactic phrase and the other as a lexical item, or posited some sort of transformation from a syntactic phrase into a lexical item. In this paper, I show empirical and conceptual problems for earlier studies, and present an alternative account in terms of Talmy's (2000) theory of lexicalization. Unlike Talmy who proposed [Path] conflation into [MOVE] for Korean, I suggest several types of [Co-Event] conflation; e.g. [$_{Co-Event}$ Manner] conflation as in kwul-e-kata 'to go by rolling', [$_{Co-Event}$ Concomitance] conflation as in ttal-a-kata 'to follow', [$_{Co-Event}$ Concurrent Result] conflation as in cap-a-kata 'to catch somebody and go', etc. The present proposal not only places Korean compound verbs in a broader picture of cross-linguistic generalizations, but, when viewed from Jackendoff's (1997) productive vs. semi-productive morphology, provides a natural account for classifying the compounds that allow -se intervention from those that do not.

• 한국동물학회:학술대회논문집
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• 한국동물학회 2003년도 한국생물과학협회 학술발표대회
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• pp.149.3-149
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• 2003

No Abstract, See Full Text

• 정보보호학회논문지
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• 제32권5호
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• pp.1009-1017
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• 2022

로그 데이터는 정보 시스템의 주요 동작과 상태를 이해하고 판단하는 근거로 사용되어 왔으며, 여러 보안 분야 응용에서도 중요한 입력 데이터로 사용된다. 로그 데이터로부터 필요한 정보를 얻어 이를 근거로 의사 결정을 하고, 적절한 대응 방안을 취하는 것은 시스템을 보호하고 안정적으로 운영하는 데 있어 필수적인 요소이지만, 로그의 종류와 양이 폭발적으로 증가함에 따라 기존 도구들로는 효과적이고 효율적인 대응이 쉽지 않은 상황이다. 이에 본 연구에서는 자연어 처리 기반의 머신 러닝을 이용해 멀티 소스 이벤트 로그의 보안 심각도를 여러 단계로 분류하는 방법을 제안하였으며, 472,972건의 훈련 및 테스트 샘플을 이용하여 실험을 수행한 결과 99.59%의 정확도를 달성하였다.