• Title/Summary/Keyword: historical change

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An Analysis of the Effect of Climate Change on Nakdong River Environmental Flow (낙동강 유역 환경유량에 대한 기후변화의 영향 분석)

  • Lee, A Yeon;Kim, Sangdan
    • Journal of Korean Society on Water Environment
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    • v.27 no.3
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    • pp.273-285
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    • 2011
  • This study describes the modeling of climate change impact on runoff across southeast Korea using a conceptual rainfall-runoff model TANK and assesses the results using the concept of environmental flows developed by International Water Management Institute. The future climate time series is obtained by scaling the historical series, informed by 4 global climate models and 3 greenhouse gas emission scenarios, to reflect a $4.0^{\circ}C$ increase at most in average surface air temperature and 31.7% increase at most in annual precipitation, using the spatio-temporal changing factor method that considers changes in the future mean seasonal rainfall and potential evapotranspiration as well as in the daily rainfall distribution. Although the simulation results from different global circulation models and greenhouse emission scenarios indicate different responses in flows to the climate change, the majority of the modeling results show that there will be more runoff in southeast Korea in the future. However, there is substantial uncertainty, with the results ranging from a 5.82% decrease to a 48.15% increase in the mean annual runoff averaged across the study area according to the corresponding climate change scenarios. We then assess the hydrologic perturbations based on the comparison between present and future flow duration curves suggested by IMWI. As a result, the effect of hydrologic perturbation on aquatic ecosystems may be significant at several locations of the Nakdong river main stream in dry season.

The timing of unprecedented hydrological drought under climate change

  • Yusuke Satoh;Hyungjun Kim
    • Proceedings of the Korea Water Resources Association Conference
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    • 2023.05a
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    • pp.48-48
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    • 2023
  • The intensified droughts under climate change are expected to threaten stable water resource availability. Droughts exceeding the magnitude of historical variability could occur increasingly frequently under future climate conditions. It is crucial to understand how drought will evolve over time because the assumption of hydrological stationarity of the past decades would be inappropriate for future water resources management. However, the timing of the emergence of unprecedented drought conditions under climate change has rarely been examined. Here, using multimodel hydrological simulations, we investigate the changes in the frequency of hydrological drought (defined as abnormally low river discharge) under high and low greenhouse gas concentration scenarios and with existing water resources management and estimate the timing of the first emergence of unprecedented regional drought conditions that persist for over several consecutive years. This new metric enables a new quantification of the urgency of adaptation and mitigation with regard to drought under climate change. The times are detected for several sub-continental-scale regions, and three regions, namely, southwestern South America, Mediterranean Europe, and northern Africa, exhibit particularly robust and earlier critical times under the high-emission scenario. These three regions are expected to confront unprecedented conditions within the next 30 years with a high likelihood, regardless of the emission scenarios. In addition, the results obtained herein demonstrate the benefits of the lower-emission pathway in reducing the likelihood of emergence. The Paris Agreement goals are shown to be effective in reducing the likelihood to the unlikely level in most regions. Nevertheless, appropriate and prior adaptation measures are considered indispensable to when facing unprecedented drought conditions. The results of this study underscore the importance of improving drought preparedness within the considered time horizons.

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A Phonetic Investigation of Korean Monophthongs in the Early Twentieth Century (20세기 초 한국어 단모음의 음향음성학적 연구)

  • Han, Jeong-Im;Kim, Joo-Yeon
    • Phonetics and Speech Sciences
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    • v.6 no.1
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    • pp.31-38
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    • 2014
  • The current study presents an instrumental phonetic analysis of Korean monophthong vowels in the early twentieth century Seoul Korean, based on audio recordings of elementary school textbooks Botonghakgyo Joseoneodokbon (Korean Reading Textbook for Elementary School). The data examined in this study were a list of the Korean mono syllables (Banjeol), and a short passage, recorded by one 41-year-old male speaker in 1935, as well as a short passage recorded by one 11-year-old male speaker in 1935. The Korean monophthongs were examined in terms of acoustic analysis of the vowel formants (F1, F2) and compared to those recorded by 18 male speakers of Seoul Korean in 2013. The results show that in 1935, 1) /e/ and /ɛ/ were clearly separated in the vowel space; 2) /o/ and /u/ were also clearly separated without any overlapping values; 3) some tokens of /y/ and /ø/ were produced as monophthongs, not as diphthongs. Based on the results, we can observe the historical change of the Korean vowels over 80-90 years such as 1) /e/ and /ɛ/ have been merged; and 2) /o/ has been raised and overlapped with /u/.

Foreign and Domestic Influence of the First Half of the Twentieth-Century American Furniture

  • Kim, Seong-Ah
    • Journal of the Korea Furniture Society
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    • v.18 no.4
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    • pp.324-336
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    • 2007
  • Throughout the twentieth century, American furniture was subject to a number of influences-both domestic and foreign. Especially, in the first half of the twentieth century, there were strong foreign influences compare to the later half of the century. Therefore, this study aimed for discussing foreign influences and for addressing issues such as attitudes toward materials, ornamentation, and technology. As a result, this study suggests how American furniture becomes instinctive moving away from strong foreign influences from the second half of the century. The twentieth century was a period of rapid and dynamic change for American furniture design. In many ways, the designs throughout the century were reflective of the social, political, and economic culture of the time. With the birth of the modern movement in Europe and a strong influx of foreign immigrants, American design in the first half of the century was characterized by a reliance on European and foreign influences. However, after the two world wars, strong domestic influences came into play. The two world wars provided the essential catalysts for change: new materials, developing technology, and changes in life style and consumer values. A historical examination of design trends and individual designers illustrates how American furniture design evolved during this period.

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A Study on the Spatial Configuration and Design Method in Pinakothek der Moderne - Foused on the Harmony and Coexistence of the Classic and Modern Design - (모데르네 피나코텍의 공간구성과 디자인 방법에 관한 고찰 - 고전적 디자인과 현대 디자인의 조화와 공존을 중심으로 -)

  • 박성호;박무호;장찬범;임채진
    • Korean Institute of Interior Design Journal
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    • v.13 no.4
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    • pp.138-146
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    • 2004
  • The museum has been developed and changed variety by a social change and extention of its concept and social role. At modem times, context is a important fact in museum architecture in the city. These mean that museum architecture is combined with rather the relationship its surroundings than completion its constructing. Recently, Many studies were continued on the assumption that the function and role of museum has been changed variety by a social change. But most of them were centered on changing choronogical typology of museum layouts and classifing morphology of museum. This study is to analyze harmony and connection about pinakothek der moderne with surounding conditions and to know how to design its spacial configuration. As a result of this study, firstly, it was confirmed that pinakothek der moderne came up with an idea which was design method about planning of modern museum in classic museums district. Seondly, it come under the modern museum but has classical spacial form and faculty. These mean that it is not only a solution about required functions but also a trial that is a significance for solving historical context and esteeming the classic space.

Sea-level Change and Coastal Erosion (해수면 변화와 해안 침식)

  • Jeon, Dong-Chull
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.7 no.4
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    • pp.289-304
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    • 1995
  • Time series of the relative sea levels at the selected tide-gauge stations in the North Pacific and historical aerial photographs in the Hawaiian Islands are analyzed. Long-term rising trend of sea level ranges from +1 to +5 mm/yr at most of the stations, which is primarily due to global warming and tectonic motion of the plates. The annual and interannual fluctuations of sea level result from the thermal expansion/contraction of sea-surface layer due to the annual change of the solar radiation and possibly from a coupled ocean-atmosphere phenomenon associated with an ENSO event, respectively. Sea-level changes in three different time-scales (linear trend. annual oscillation, and interannual fluctuation) and their quantitative contribution to the shoreline changes as a result of long-term cross-shore sediment transport arc hypothesized.

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Vulnerability Assessment of Water Supply in Agricultural Reservoir Utilizing Probability Distribution and Reliability Analysis Methods (농업용 저수지 공급량과 수요량의 확률분포 및 신뢰성 해석 기법을 활용한 물 공급 취약성 평가)

  • Nam, Won-Ho;Kim, Tae-Gon;Choi, Jin-Yong;Lee, Jeong-Jae
    • Journal of The Korean Society of Agricultural Engineers
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    • v.54 no.2
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    • pp.37-46
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    • 2012
  • The change of rainfall pattern and hydrologic factors due to climate change increases the occurrence probability of agricultural reservoir water shortage. Water supply assessment of reservoir is usually performed current reservoir level compared to historical water levels or the simulation of reservoir operation based on the water budget analysis. Since each reservoir has the native property for watershed, irrigation district and irrigation water requirement, it is necessary to improve the assessment methods of agricultural reservoir water capability about water resources system. This study proposed a practical methods that water supply vulnerability assessment for an agricultural reservoir based on a concept of probabilistic reliability. The vulnerability assessment of water supply is calculated from probability distribution of water demand condition and water supply condition that influences on water resources management and reservoir operations. The water supply vulnerability indices are estimated to evaluate the performance of water supply on agricultural reservoir system, and thus it is recommended a more objective method to evaluate water supply reliability.

RAINFALL AND RUNOFF VARIATION ANALYSIS FOR WATER RESOURCES MANAGEMENT STRATEGIES

  • Sang-man;Heon, Joo-;Jong-ho;Kum-young
    • Water Engineering Research
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    • v.5 no.3
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    • pp.111-121
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    • 2004
  • For the long-term strategic water resources planning, forecasting the future streamflow change is important to meet the demand of a growing society. The streamflow variation to the decade-long precipitation was investigated for the two major stage gauging stations in Korea. Precipitation and runoff characteristics have been analyzed at Yongwol stream stage in the Han River as well as Sutong stream stage in the Kum River for the future water resources management strategies. Monte Carlo method has been applied to estimate the future precipitation and runoff. Based on the trend line of 10-year moving average of runoff depth for the historical runoff records, the relation between runoff and the time variation was examined in more detail using regression analysis. This study showed that the surface flows have been significantly decreased while precipitation has been stable in these basins. Decreasing in runoff reflects the regional watershed characteristics such as forest cover changes. The findings of this study could contribute to the planning and development for the efficient water resources utilization.

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A Study on the Aesthetic Value of the Clothes of the Stripe Pattern in a Historical Point of View - From Medieval Age to the Late Nineteenth Century - (줄무늬 문양 복식의 미적 가치에 관한 역사적 고찰 -중세부터 19C 말을 중심으로 -)

  • Park Sun-Kyung
    • The Research Journal of the Costume Culture
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    • v.13 no.3 s.56
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    • pp.391-405
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    • 2005
  • This study puts emphasis on showing the change of Stripe Pattern, which has been popular for a long period of time in many societies, with change in time, assessing its value as an art. During medieval period, Strife Pattern had a strong negative meaning as a sign of disgrace or inferiority, or had been used as discrimination against a mental or a sinner, who had been rejected or banished from the society. Through French Revolution, Stripe Pattern has become a symbol of liberty and equality, furthermore, the notion of society as well as countries. This event had positively affected on reevaluating its image, from inferior, negative to significant, artistic. Eventually the variety of aesthetic values of Stripe Pattern led its way to the variation of its functional value expanding its use other than fashion industry. It is anticipated that our fashion industry will flourish in creating new, creative design by understanding design and appreciating their aesthetic values with their applications to human sensibility.

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The Evolution of Video Game Industry: Applying the Industrial Organization Model to the U.S. Video Game Market (비디오 게임 산업의 진화: 미국 비디오 게임 시장에 대한 산업조직론적 접근)

  • Seo, Sangho
    • Journal of Korea Game Society
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    • v.12 no.6
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    • pp.47-58
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    • 2012
  • Video game industry has undergone the drastic changes for forty-year history. The purpose of this study was to gain an understanding of the historical evolution of the U.S. video game industry. To achieve this goal, this study has chosen the industrial organization model as the theoretical framework. This study found that the market structure as well as the market conduct in the U.S. video game industry changed drastically. This study concludes that the change of the market structure of the U.S. video game industry relates to the change of market conduct. This study could serve as the basis for future research on the economic analysis of video game industry.