• 천문학회지
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• 제36권spc1호
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• pp.75-81
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• 2003

Changes in the earth's climate depend on changes in the net sunlight reaching us. The net depends on the sun's output and earth's reflectance, or albedo. Here we develop the limits on the changes in the sun's output in historical times based on the physics of the origin of solar cycle changes. Many have suggested that the sun's output could have been $0.5\%$ less during the Maunder minimum, whereas the variation over the solar cycle is only about $0.1\%$. The frequencies of solar oscillations (f- and p-modes) evolve through the solar cycle, and provide the most exact measure of the cycle-dependent changes in the sun. But precisely what are they probing? The changes in the sun's output, structure and oscillation frequencies are driven by some combination of changes in the magnetic field, thermal structure and velocity field. It has been unclear what is the precise combination of the three. One way or another, this thorny issue rests on an understanding of the response of the solar structure to increased magnetic field, but this is complicated. Thus, we do not understand the origin of the sun's irradiance increase with increasing magnetic activity. Until recently, it seemed that an unphysically large magnetic field change was required to account for the frequency evolution during the cycle. However, the problem seems to have been solved (Dziembowski, Goode & Schou 2001) using f-mode data on size variations of the sun. From this and the work of Dziembowski & Goode (2003), we suggest that in historical times the sun couldn't be much dimmer than it is at activity minimum.

• 한국해양공학회지
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• 제20권6호
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• pp.54-60
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• 2006

This study discusses characteristic of spatiotemporal changes of the sand barrier in the Nakdong estuarine for the last century, focusing on geomarphologic evolution and mobility of sand barriers in the view of coastal engineering. The Nakdong estuarine, the research subject, has a complexly changing natural environment by interaction between ground and marine elements such as ocean wave, tidal current, sediment, etc. Moreover, recently, unnatural geomorphologic changes (e.g., seaside reclamation, new harbor construction, etc.) has been radically increased in this area with increasing desire for coastal development. Because of this, its sand barrier has developed quite unstable condition. Therefore, to identify the development process of geomorphologic changes in this area, required is a close examination on historical characteristics of spatiotemporal changes of the sand barrier in relation to surrounding seaside reclamation and physical environmental changes. This study, based on the marine charts published in between 1927 and 1995 year, analyzes the length and area of the sand barrier for the last hundred years, and investigates the cause of the changes by looking into the change of water depth for the last two years and doing ocean-physical site observations. In conclusion, the sand barrier of the Nakdong estuarine expands toward the open sea by $7.4{\sim}26m$ in annual average, maintaining a fixed distance of $1,241{\sim}1.279m$, and its area is expected to increase about $2.8km^2$ annually. This is characterized by the wocean wave from the open sea and the discharge of Nakdong River.

• 한국수학사학회지
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• 제20권4호
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• pp.71-84
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• 2007

베르누이가 처음으로 자연수 k에 대하여 합 $S_n(k)=\sum_{{\iota}=1}^n\;{\iota}^k$에 관한 공식들을 유도하는 방법을 발견하였다([4]). 그 이후, 리만 제타함수와 관련된 베르누이 수와 오일러 수에 관한 성질들이 연구되어왔다. 최근에 김태균은 $\mathbb{Z}_p$상에서 p-진 q-적분과 관련된 확장된 q-베르누이 수와 q-오일러 수, 연속된 q-정수의 멱수의 합에 관한 성질들을 밝혔다. 본 논문에서는 연속된 q-정수의 멱수의 합에 관한 역사적 배경과 발달과정을 고찰하고, 오일러 및 베르누이 수와 관련된 리만 제타함수가 해석적 함수로써 값을 가지는 문제를 q-확장된 부분의 이론으로 연구되어온 q-오일러 제타함수에 대해 체계적으로 논의한다.

• 한국가정과교육학회지
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• 제8권2호
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• pp.65-79
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• 1996

This study proposes a model curriculum for Vocational Home Economics High School in the 7th Curriculum Revision. The model in the study is first drawn from the assumptions that reflect ever changing demands of industrial society for Home Economics education. Another perspective employed in the study is historical analysis that focuses on the evolution of the Vocational Home Economics Curricula from the 1st through the 6th revision. This study also employes comparative research tools for the national level comparison such as USA, Japan, Taiwan, and Korea. The proposed model curriculum in this study is concluded from those step-by-step studies as follows：1) Problem definition and design in current curriculum for Vocational Home Economics high school； 2) Needs and roles analysis of Vocational Home Economics high school for the future； and 3)Historical analysis of our curriculum revisions in the past and coparative analysis with other countries. Authors conducted this research project for 3 month period from June 15, 1996 to September 15, 1996. During this period, authors collected the data and information through those method as an extensive literature review, survey and interview, and curriculum specialist conference. The key and critical features of the proposed curriculum in the study are as follows：1) In the numbers of department, a proposed model curriculum offers 8 as opposed to 6 in the 6th revision, reflecting two additional departments of “Elderly Welfare”and “Cosmotology”. 2) In the statement of educational objectives, a model curriculum emphasizes a more concrete statement to each specific skills according to the changing societal needs. 3) In the numbers of total subject matters, there would be 40 in the new as opposed to 23 in the current curriculum. Among these changes, 17 would occurr in the newly introduced subject matters, while 11 would simply change the subject matter name. Among 40 subject matter, “Introduction to Computer” and “Home Economics in Vocational Education”would be required subject matter. 4) In the total numbers of required unit for graduation in three years, a model offers 86∼132 unit. A maximum unit for each subject matter would be 12.

• 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.

• 한국기후변화학회지
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• 제6권2호
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• pp.95-104
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• 2015

To discuss whether we have credible estimations about historical surface temperature evolution since industrial revolution or not, present study investigates consistencies and differences of averaged surface air temperature since 1900 between the multiple data sources: Hadley Center Climate Research Unit (HadCRU4) surface air temperature data, ECMWF 20 Century Reanalysis data (ERA20CR), and NCEP 20 Century Reanalysis data (NCEP20CR). Averaged surface temperatures are obtained for the global, polar (90S~60S, 60N~0N), midlatitude (60S~30S, 30N~60N), tropical (30S~30N) region, separately. From the analysis, we show that: 1) spatio-temporal inhomogenity and scarcity of HadCRU4 data are not major obstacles in the reliable estimation of global surface air temperature. 2) Globally averaged temperature variability is largely contributed by those of tropical and midlatitude, which occupy more than 70% of earth surface in area. 3) Both data show consistent temperature variability in tropical region. 4) ERA20CR does not capture warm period over Arctic region in early 1900s, which is obvious feature in HadCRU4 data. Discrepancies among datasets suggest that high-level caution is needed especially in the interpretation of large Arctic warming in the early 1900s, which is often regarded as a natural variability in the Arctic region.

• 복식문화연구
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• 제31권5호
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• pp.573-585
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• 2023

Comprehending the prevailing ideals of the body within a specific era requires grasping the intricate interplay between social phenomena and the evolution of clothing. Accordingly, this study investigates the distinctive facets of the perception of the Neo-Confucian body as reflected in men's dress during the Joseon Dynasty. We examine a comprehensive body of scholarship, literature, and historical records concerning the body and dress. Additionally, we also employ a framework developed by M. Y. Kim, which categorizes the Neo-Confucian body in three ways: as the natural body, the cultural body, and the body as a fully-realized moral subject. Our findings unveil three crucial insights: firstly, guided by Neo-Confucian discourse positing appearance as a manifestation of innate energy (氣), men's dress was deliberately designed to demarcate stylistic distinctions in women's dress; secondly, the Chinese gwan (冠) was employed as a tool of self-cultivation (修身) to symbolize the legitimacy of Joseon's Neo-Confucian governance; and thirdly, sim-ui (深衣), a philosophical emblem of Confucianism extensively represented across through an intensified exploration of historical sources, served as a means to consolidate the political standing of the Neo-Confucian faction. As a consequence of these factors, the attire of noble men conferred upon them both sexual and moral ascendancy as political entities; men's dress became a visual manifestation of the legitimacy of their power, thus embodying Neo-Confucian ideals. This study carries significance by applying a discourse analysis approach to Korean dress research and elucidating the factors underlying the development of men's dress during the Joseon Dynasty.

• 한국간담췌외과학회지
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• 제28권3호
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• pp.271-282
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• 2024

The history of liver surgery is a tale of progressive resolution of issues presenting one after another from ancient times to the present days when dealing with liver ailments. The perfect knowledge of human liver anatomy and physiology and the development of a proper liver resective surgery require time and huge efforts and, mostly, the study and research of giants of their own times, whose names are forever associated with anatomical landmarks, thorough descriptions, and surgical approaches. The control of parenchymal bleeding after trauma and during resection is the second issue that surgeons have to resolve. A good knowledge of intra and extrahepatic vascular anatomy is a necessary condition to develop techniques of vascular control, paving the way to liver transplantation. Last but not least, the issue of residual liver function after resection requires advanced techniques of volume redistribution through redirection of blood inflow. These are the same problems any young surgeon would face when approaching liver surgery for the first time. Therefore, obtaining a wide picture of historical evolution of liver surgery could be a great starting point to serve as an example and a guide.

• 한국실내디자인학회논문집
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• 제13권5호
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• pp.106-113
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• 2004

The purpose of this study is to present the dwelling space by attaching or inserting the mobile space unit to the fixed building by providing the temporary dwelling space for those suffering from flood disaster, natural disaster or solitary old people or the space and program that the completed building in the city can not provide such as temporary events in the bridge, passage space, walking space for the handicapped, stores located between street blocks, and plaza. Therefore, this study was intended to investigate temporary dwelling space through the composition of space and the experiment of the applicability of the program through the methods of movement, folding, module, expansion and evolution of mobile space. An attempt was made to apply the concept of ‘mobile space’ to the dwelling space not only with a focus on the freedom of variable and changeable physical movement but also with a focus on the existence of the nomad and the way of thinking that bleaks away from a given value system and code, creates a new value and continues to move to a new domain. This study attempted to analyze how the concept of ‘mobile space’ has been developed in what form and method they have been applied and interpreted in the historical background. It attempted to resolve the concepts of movement and mobility through the experiment so that they might apply to the space of contemporary city. This study attempted to experiment this possibility using the mobile space unit and apply it.

• 대한교통학회지
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• 제32권5호
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• pp.522-530
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• 2014

교통관리센터에 축적되어 있는 속도 이력데이터에는 반복 비반복 정체 시공간 전개에 대한 상세한 정보가 모두 들어있으나, 도해법에 의해 다루어져 왔기 때문에 많은 양의 이력데이터를 처리하여 교통상황예측이나 정보제공에 활용할 수 없는 한계가 존재하였다. 본 논문에서는, 기존의 Classification과 Density-Based Clustering 알고리즘을 속도 시공간 데이터 특성에 맞게 조합하고 변형하여 정체 시공간 영역을 자동 인식하는 알고리즘과, 정체파급길이, 파급속도, 해소속도 등 정체 시공간 전개 패턴의 특성치를 산정하는 알고리즘을 개발하였다, 본 알고리즘은, 교통관리센터에 축적되어 있는 방대한 양의 이력데이터를 자동으로 분석하여 자세한 정체 관련 정보를 추출할 수 있고, 산정된 특성치를 가지고 각 센터의 필요에 따라 다양한 정보를 2차 생성하고 활용할 수 있는 장점이 있다. 본 연구결과는 향후 반복 비반복 정체에 대한 예측과 대응이 획기적으로 개선되는데 초석이 될 것으로 기대된다.