• 제목/요약/키워드: historical regions

검색결과 226건 처리시간 0.029초

나선은하 HII 영역과 우리은하 구상성단의 중$\cdot$저분산 스펙트럼 (SPECTRA OF HII REGIONS IN SPIRAL GALAXIES AND GALACTIC GLOBULAR CLUSTERS)

  • 천문석;송영종
    • 천문학논총
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    • 제15권spc1호
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    • pp.1-13
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    • 2000
  • We review the early historical developement of astronomical spectrographs, properties of emission line spectra of HII regions in spiral galaxies, and absorption line features of galactic globular clusters. Emission line spectra of HII regions within three spiral galaxies NGC 300, NGC 1365, and NGC 7793, which were observed from AAT/IPCS, had been analysed, and we discuss the abundances of elements in HII regions and the radial abundace gradients through the galaxies. The radial UBV color variations of two globular clusters, NGC 1851 and NGC 2808, were examined for correlations with radial variations of several absorption lines in the integrated spectra, which were obtained from SAAO 74 inch telescope and image tube spectrograph. Nine giant star's spectra in NGC 3201 were also obtained and analysed for the radial abundance gradients in the globular cluster. The results show that the presence of a radial color gradient in a globular cluster is correlated with the presence of abundance gradients. Finally, we suggest some scientific programs for the new high dispersion spectrograph, which will be installed to the BOAO 1.8m telescope.

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Evaluating the Spatio-temporal Drought Patterns over Bangladesh using Effective Drought Index (EDI)

  • Kamruzzaman, Md.;Hwang, Syewoon;Cho, Jaepil;Park, Chanwoo
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2018년도 학술발표회
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    • pp.158-158
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    • 2018
  • Drought is a recurrent natural hazard in Bangladesh. It has significant impacts on agriculture, environment, and society. Well-timed information on the onset, extent, intensity, duration, and impacts of drought can mitigate the potential drought-related losses. Thus, drought characteristics need to be explained in terms of frequency, severity, and duration. This paper aims to characterize the spatial and temporal pattern of meteorological drought using EDI and illustrated drought severity over Bangladesh. Twenty-seven (27) station-based daily rainfall data for the study period of 1981-2015 were used to calculate the EDI values over Bangladesh. The evaluation of EDI is conducted for 4 sub-regions over the country to confirm the historical drought record-developed at the regional scale. The finding shows that on average, the frequency of severe to extreme drought is approximately 0.7 events per year. As a result of the regional analysis, most of the recorded historical drought events were successfully detected during the study period. Additionally, the seasonal analysis showed that the extreme droughts were frequently hit in northwestern, middle portion of the eastern and small portion of central parts of Bangladesh during the Kharif(wet) and Rabi(dry) seasons. The severe drought was affected recurrently in the central and northern regions of the country during all cropping seasons. The study also points out that the northern, south-western and central regions in Bangladesh are comparatively vulnerable to both extreme and severe drought event. The study showed that EDI would be a useful tool to identify the drought-prone area and time and potentially applicable to the climate change-induced drought evolution monitoring at regional to the national level in Bangladesh. The outcome of the present study can be used in taking anticipatory strategies to mitigate the drought damages on agricultural production as well as human sufferings in drought-prone areas of Bangladesh.

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세계화시대에 적실한 지역연구방법론 모색 -세계체제론적 지역지리학의 보완을 중심으로- (Developing a New Area Study Methodology Suitable to the Globalization Era : With Revision of the Regional Geography of World-Systems.)

  • 이재하
    • 한국지역지리학회지
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    • 제3권1호
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    • pp.115-134
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    • 1997
  • 본 연구는 세계화시대에 적실한 지역연구방법론을 새롭게 모색하기 위하여, 지리학에서 개발된 다양한 지역연구방법론을 검토하고, 그 가운데 세계화 현상을 이론적으로 설명해주는 세계체제론에 기초한 세계체제론적 지역지리학의 내용을 자세히 살펴보았으며, 아울러 그것이 세계화시대에 보다 적실한 지역연구방법론이 될 수 있도록 그 문제점을 보완하여 수정된 세제체제론적 지역지리학을 제시하여 보았다. 수정된 세계체제론적 지역지리학에서는, 지역(역사지역)은 세제경제체제의 재생산적인 일반 메커니즘이 지역의 정치적, 경제적, 사회적 요소 또는 동인 이외에 위치적, 자연적, 문화적 요소와도 함께 작용하여 형성된다고 보았으며, 지역성은 경제적 특성에만 치중할 것이 아니라 공간적, 사회적, 문화적, 정치적 등의 특성도 분석하여 보다 종합적으로 규명될 필요가 있으며, 지역구분에서는 세계경제의 일반메커니즘에 의한 경제적 경계와 함께 정치적 경계도 동시에 고려할 필요가 있으며, 아울러 국가단위지역도 중요한 연구대상 지역으로 다루어져야 한다고 수정 제안하였다.

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조선왕조실록에 나타난 호랑이, 늑대, 표범의 서식분포 (Habitat Distribution of Tiger, Wolf, and Leopard in Joseonwangjosilok)

  • 김남신;차진열;이승은;임치홍
    • 한국환경복원기술학회지
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    • 제22권4호
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    • pp.35-45
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    • 2019
  • The objective of this study is to analyze habitat distribution on tiger, wolf, and leopard in Joseonwangjosilok. Nowaday, we only come to meet these kind of animals at the historical records because of haman-induced habitat encroachment. Historically, extinct animal became an object of game by people. So, we try to get distribution information for restoration on historical extinct animals. We made distribution map by constructing 402 counts on tiger(350), leopard(51) and wolf(1) recordsfrom 14th to Early 20th century for study. Analyzing historical materials, criteria for data analysis took into account objectivity, location information, accuracy for extinct animals. We carried out location identification of animals by using geocoding comparing with geographical name of the Joseon Dynasty period, topographic map of time under the rule of Japanese imperialism, present place name and historical materials. Database items are constructed 20 types for example appearance year of animal, population, location, damage, etc. As a result of analysis for appearance regions, tigers were recorded in capital area of higher density population intensively, and also were frequently seen at Daegu, Andong etc. Leopard and wolf were founded at regionally Gyeonggi-do and Jinju with limitation, relatively seen a few number. The reason of the appearance records like this, tiger prefer game of open and water-front area in near human residential area, there are lots of historical records such as 'Hosang'(mourning someone who killed by Tiger) and hunting. But leopard and wolf inhabit rocky area and dense forest, the reason why they made a few contact with human. Results of this are expect to be applicable restoration research for extinct animal by providing for populations, habitat environments and distribution information.

백두산의 역사시대 분화 기록에 대한 화산학적 해석 (Volcanological Interpretation of Historical Eruptions of Mt. Baekdusan Volcano)

  • 윤성효
    • 한국지구과학회지
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    • 제34권6호
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    • pp.456-469
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    • 2013
  • 백두산 화산에서 분화한 것으로 평가되는 역사시대 분화사건을 문헌에서 발굴하여 화산학적 해석을 하였다. 밀레니엄 대분화로부터 31건 이상의 화산 분화사건을 발굴하였으며, 대부분 화산재를 분화하여 인근 지역으로 확산시키면서 강하화산재를 발생시킨 플리니안 분화 사건이 많았다. 1903년의 기록은 천지 내에서의 수증기마그마성 분화 또는 불카니안 분화에 의한 기록이었다. 역사시대의 분화 기록과 2002년에 나타난 화산 분화 전조현상 등으로부터 백두산은 잠재적인 분화가능성을 가진 활화산으로 평가된다.

Seismic assessment of historical masonry structures: The case of Amasya Taşhan

  • Karaca, Zeki;Turkeli, Erdem;Pergel, Senol
    • Computers and Concrete
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    • 제20권4호
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    • pp.409-418
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    • 2017
  • Turkey owns a very important cultural and historical heritage that bears the traces of thousands of years of culture and civilization. It is an inevitable duty to carry these treasuries to the future generations. In this paper, structural safety assessment and strengthening stages of one of these important historical heritages namely Amasya Taşhan was investigated in details as a case study. For this purpose, the detailed architectural projects of the structure with the information of all load carrying and structural elements were prepared. Then, the structural dynamic analyses were performed by using SAP2000. The internal forces obtained from the dynamic analyses determined the weak regions. By obtaining the information from dynamic analyses, the method of state of the art technique of application of the structure that needs structural strengthening was selected. The last step is the application of these precautions to the whole structure. At the end of this study, this study not also contains several strengthening techniques that is used in one masonry structure together but also provides a useful reference to the practicing engineers.

Mining Spatio-Temporal Patterns in Trajectory Data

  • Kang, Ju-Young;Yong, Hwan-Seung
    • Journal of Information Processing Systems
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    • 제6권4호
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    • pp.521-536
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    • 2010
  • Spatio-temporal patterns extracted from historical trajectories of moving objects reveal important knowledge about movement behavior for high quality LBS services. Existing approaches transform trajectories into sequences of location symbols and derive frequent subsequences by applying conventional sequential pattern mining algorithms. However, spatio-temporal correlations may be lost due to the inappropriate approximations of spatial and temporal properties. In this paper, we address the problem of mining spatio-temporal patterns from trajectory data. The inefficient description of temporal information decreases the mining efficiency and the interpretability of the patterns. We provide a formal statement of efficient representation of spatio-temporal movements and propose a new approach to discover spatio-temporal patterns in trajectory data. The proposed method first finds meaningful spatio-temporal regions and extracts frequent spatio-temporal patterns based on a prefix-projection approach from the sequences of these regions. We experimentally analyze that the proposed method improves mining performance and derives more intuitive patterns.

Stochastic simulation based on copula model for intermittent monthly streamflows in arid regions

  • Lee, Taesam;Jeong, Changsam;Park, Taewoong
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2015년도 학술발표회
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    • pp.488-488
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    • 2015
  • Intermittent streamflow is common phenomenon in arid and semi-arid regions. To manage water resources of intermittent streamflows, stochactic simulation data is essential; however the seasonally stochastic modeling for intermittent streamflow is a difficult task. In this study, using the periodic Markov chain model, we simulate intermittent monthly streamflow for occurrence and the periodic gamma autoregressive and copula models for amount. The copula models were tested in a previous study for the simulation of yearly streamflow, resulting in successful replication of the key and operational statistics of historical data; however, the copula models have never been tested on a monthly time scale. The intermittent models were applied to the Colorado River system in the present study. A few drawbacks of the PGAR model were identified, such as significant underestimation of minimum values on an aggregated yearly time scale and restrictions of the parameter boundaries. Conversely, the copula models do not present such drawbacks but show feasible reproduction of key and operational statistics. We concluded that the periodic Markov chain based the copula models is a practicable method to simulate intermittent monthly streamflow time series.

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Tabriz on the Silk Roads: Thirteenth-Century Eurasian Cultural Connections

  • Prazniak, Roxann
    • Asian review of World Histories
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    • 제1권2호
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    • pp.169-188
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    • 2013
  • Tabriz under Mongol Ilkhanate rule commanded a global reach in the thirteenth-century Afro-Eurasian world. Tabriz functioned during this period not only as a commercial emporium and diplomatic center but as a seat of innovative artistic and intellectual activity. Consideration of Tabriz as a world historical city offers insight into the economic and social dynamics that shaped a critical passage in Eurasia's history including regions of the Mediterranean and East Asian zones.

중국 역사문화도시의 공공조형물에서 나타나는 표현 특성과 장소성 연구 (A Study on Expression Characteristics and Placeness in Public Sculptures of Chinese Historical and Cultural Cities)

  • 이지엔화;윤지영;왕단
    • 한국콘텐츠학회논문지
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    • 제20권10호
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    • pp.216-232
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    • 2020
  • 본 연구는 중국 역사문화도시의 현대 공공조형물의 표현 특성을 분석, 공공조형물이 어떻게 효율적으로 역사 문화 요소에 개입하여, 장소성을 표출할 수 있는가를 파악하고자 함으로서 공공조형물이 지닌 장소적 의미와 적용에 대한 기초자료를 제공하고자 한다. 연구방법은 첫째, 문헌고찰로 역사 문화 도시의 개념, 장소성의 개념 등을 이해하여 이론적 기반을 제공하였다. 둘째, 선행연구 고찰을 통해 공공조형물의 표현특성을 분석하며 10명의 조형 및 디자인 전문가로부터 특성에 대한 평가를 통해 장소성과 관련이 가장 많은 8개 요소를 선정하였다. 셋째, 사례분석으로 중국의 대표적인 도시인 상해, 북경, 광주의 공공조형물 중 발행량이 가장 많은 7개 잡지에서 60개 사례를 선정하여 전문가의 평가를 통해 최종 15개 공공조형물을 선정하였다. 연구 결과에 따르면, 역사 문화 요소의 발굴이나 도시 현대 인문 정취를 표현함에 있어서 세 도시의 공공 조형물 모두 각기 다른 장소성을 구현하였다. 독자적인 선진 기술이 가져온 예술적 독창성과 대중과의 상호작용을 결합하여 도시만의 독특한 역사 인문적 요소를 활용하여 다른 지역과 다른 장소를 만들어내는 것이 공공 조형물의 발전 추세이다.