• Title/Summary/Keyword: Historical Analysis

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Towards performance-based design under thunderstorm winds: a new method for wind speed evaluation using historical records and Monte Carlo simulations

  • Aboshosha, Haitham;Mara, Thomas G.;Izukawa, Nicole
    • Wind and Structures
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    • v.31 no.2
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    • pp.85-102
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    • 2020
  • Accurate load evaluation is essential in any performance-based design. Design wind speeds and associated wind loads are well defined for synoptic boundary layer winds but not for thunderstorms. The method presented in the current study represents a new approach to obtain design wind speeds associated with thunderstorms and their gust fronts using historical data and Monte Carlo simulations. The method consists of the following steps (i) developing a numerical model for thunderstorm downdrafts (i.e. downbursts) to account for storm translation and outflow dissipation, (ii) utilizing the model to characterize previous events and (iii) extrapolating the limited wind speed data to cover life-span of structures. The numerical model relies on a previously generated CFD wind field, which is validated using six documented thunderstorm events. The model suggests that 10 parameters are required to describe the characteristics of an event. The model is then utilized to analyze wind records obtained at Lubbock Preston Smith International Airport (KLBB) meteorological station to identify the thunderstorm parameters for this location, obtain their probability distributions, and utilized in the Monte Carlo simulation of thunderstorm gust front events for many thousands of years for the purpose of estimating design wind speeds. The analysis suggests a potential underestimation of design wind speeds when neglecting thunderstorm gust fronts, which is common practice in analyzing historical wind records. When compared to the design wind speed for a 700-year MRI in ASCE 7-10 and ASCE 7-16, the estimated wind speeds from the simulation were 10% and 11.5% higher, respectively.

Analysis of historical drought in East Asia with CLM and CLM-VIC (CLM 및 CLM-VIC를 이용한 동아시아 지역의 과거 가뭄 분석)

  • Um, Myoung-Jin;Kim, Jeongbin;Kim, Mun Mo;Kim, Yeonjoo
    • Ecology and Resilient Infrastructure
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    • v.5 no.3
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    • pp.134-144
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    • 2018
  • In this study, the historical drought in East Asia was analyzed with the Community Land Model (CLM) and CLM-Variable infiltration capacity (CLM-VIC). The observation dataset, Climate Research Unit (CRU), were also applied to check and estimate the historical drought for 1951 - 2010. The annual precipitation, temperature and evapotranspiration by CRU, CLM and CLM-VIC were investigated before estimating the meteorological drought index, which is the Standardized precipitation evapotranspiration index (SPEI). Three variables by observation and simulations have generally similar spatial pattern in East Asia even though there are some mere differences depending on the local area. These similar patterns are also founded in the results of SPEI by CRU, CLM and CLM-VIC. However, the similarity of SPEI becomes weaker as the drought severity goes severer from D1 to D4.

Prediction of recent earthquake magnitudes of Gyeongju and Pohang using historical earthquake data of the Chosun Dynasty (조선시대 역사지진자료를 이용한 경주와 포항의 최근 지진규모 예측)

  • Kim, Jun Cheol;Kwon, Sookhee;Jang, Dae-Heung;Rhee, Kun Woo;Kim, Young-Seog;Ha, Il Do
    • The Korean Journal of Applied Statistics
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    • v.35 no.1
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    • pp.119-129
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    • 2022
  • In this paper, we predict the earthquake magnitudes which were recently occurred in Gyeongju and Pohang, using statistical methods based on historical data. For this purpose, we use the five-year block maximum data of 1392~1771 period, which has a relatively high annual density, among the historical earthquake magnitude data of the Chosun Dynasty. Then, we present the prediction and analysis of earthquake magnitudes for the return level over return period in the Chosun Dynasty using the extreme value theory based on the distribution of generalized extreme values (GEV). We use maximum likelihood estimation (MLE) and L-moments estimation for parameters of GEV distribution. In particular, this study also demonstrates via the goodness-of-fit tests that the GEV distribution can be an appropriate analytical model for these historical earthquake magnitude data.

A Media Archaeological Analysis on the Origins of Korean Broadcasting

  • Yoon, Sangkil
    • Journal of the Korea Society of Computer and Information
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    • v.27 no.8
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    • pp.91-101
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    • 2022
  • This study started with the awareness that the review of the historical origins of Korean broadcasting will be of great significance in exploring the future of Korean broadcasting, and examined the various "origins" of Korean broadcasting - colonial, Cold War, totalitarian, neoliberal. Based on the theoretical background of "media archaeology", the historical 'origin' of Korean broadcasting was applied to track the origin of Hallyu(the Korean Wave) in the 21st century by comprehensively examining the political and economic motives of the time, the state's situational awareness of problems, major broadcasting policies and broadcasting realities. As a result of the study, it came to the tentative conclusion that the historical origin of the Hallyu, which began to be formed in the 1980s, originated from the three origins of Korean broadcasting and the "synthetic mixture" in the subsequent development process.

Historical Changes of Incheon Freedom Park and Its Heritage Value Interpretation as the Historic Urban Public Park (인천 자유공원의 역사적 변천과 역사도시공원으로서의 유산 가치 해석)

  • Kim, Soon-Ki
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.41 no.4
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    • pp.30-39
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    • 2023
  • This study aims to identify the value of Incheon Freedom Park as a 'historic urban park' through the historical transition process of the park and surrounding areas. To this end, this study uses a time series analysis, as research method, based on old maps and aerial photographs to investigate the changes in the park over time and to interpret them based on the historical and cultural changes in modern and contemporary history. As a result of the study, the park not only has (1) evidence of major events in modern and contemporary history, but also (2) historical value as an urban park based on the first urban plan in Korea, and (3) very important heritage value that shows the rapidly changing civic life in modern and contemporary times. However, despite the identification of heritage values in this study, further research is needed to explore and excavate in-depth data on the park in order to more clearly identify, restore, and utilize the heritage values of the park.

A Investigation on the Soil-Peel Methods in Conservation Method of Historical Site (유구 보존방법론 중 토층전사에 관한 고찰)

  • Wi, Koang-Chul;Seo, Jeong-Ho
    • Journal of Conservation Science
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    • v.26 no.3
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    • pp.341-348
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    • 2010
  • After excavation work of relics, historical site which has historically meaningful, are preserved using the various methods. There are three method in the relocation methods that are original relocation method, the remaining structure-peel method, and soil peel method. The original relocation method is restored after relocating in historical site such as residential site, iron foundry site, kiln site, old mound. The remaining structure-peel method are restored only the feature of exposed remaining structure using polymeric resin, when it is difficult to relocate the entire remaining structure. And soil-peel method is exhibited after peeling in case when soil layers such as grave of old mound, foundation of building site, sedimentary deposit layer, shell heap, and etc. Soil-peel method becomes important historical data of changes according to environment at that time, that is, flooding by storm, traces of fire and living features of that time such as heaps of shells discarded after eating shellfish and living wastes. In particular, in case of soil layer for preparing foundation sites of building by compacting in turn soils with different components such as clay soil, rough sand soil and etc, it becomes important data which can judge foundation technology of that time. It can be said to be an important data preservation method for utilizing these historical data as historical data as well as for the purpose of education, exhibitions and public relations which can be shared not only by experts but also by general public. In this paper, we present the reliable definition of soil-peel method in various preservation methods and explain the using polymer in this method. So, we will come up with the accurate index about this method that is used the eminent analysis method for soil layer.

A Study on the Placeness of Vacant Houses in the Street of Historical Culture - Focused on HangZhou Zhongshan Road - (역사문화거리 빈집의 장소성에 관한 연구 -중국 항저우 중산로를 중심으로-)

  • Wang, Hui-Hui;Hong, Kwan-Seon
    • The Journal of the Korea Contents Association
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    • v.20 no.1
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    • pp.617-629
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    • 2020
  • In the historical and cultural blocks with the most concentrated urban cultural heritage, the development of both side streets is impacted by the development of the main street, which shows a gradual decline. The loss of placeness on both side streets has resulted in more empty houses. Therefore, it is urgent to pay attention and take countermeasures to the empty houses in historical and cultural blocks. In this study, the vacant houses on Zhongshan Road in Hangzhou, China were taken as the object of study to understand the location theory and the six dimensions of Matthew Carmona's urban design. Meanwhile, it further analyzed the evaluative features of the placeness of the vacant houses in the historical and cultural street, to provide direction and basis for the flexible using of other empty houses in Zhongshan Road. Then by applying the Analytic Hierarchy Process (AHP), it obtained the importance scale of each evaluative feature and compared the evaluation results of experts with the analysis results of cases, getting the results as follows: In the flexible application of vacant houses in historical and cultural street, the evaluation result of placeness indicates that this kind of usage should be in order of societal level, perceptional level, functional level, morphological level, visual hierarchy and temporal level; among the evaluative features, security, identity, usability, individuality, aesthetics, connection, diversity, openness, continuity, accessibility, order and history should be considered in turn.

Evaluation Research on the Protection and Regeneration of the Urban Historical and Cultural District of Pingjiang Road, Suzhou, China (중국 쑤저우 평강로 도시역사문화거리 보존 및 재생사업 평가연구)

  • Geng, Li;Yoon, Ji-Young
    • The Journal of the Korea Contents Association
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    • v.21 no.5
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    • pp.561-580
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    • 2021
  • This study analyses the historical and cultural streets at Pinggang Road in the city of Suzhou, by understanding the development and conservation of the area, and uses the following ways to investigate its development, re-organization, and current state. This paper comprehensively compares, collates and investigates 4 different historical and cultural areas in Insadong and Samcheong-dong in South Korea, and South Luogu Lane in China. From initial research and analysis, this paper gathers the cultural, economic, and societal perspectives as non-physical measures, and spatial structure, road structure, and building maintenance as physical factor framework. It is significant in that it can provide an evaluation model for the preservation and regeneration of historical and cultural streets by presenting the viewpoint of complex development of non-physical and physical elements in Pyeonggang-ro. In addition, it is necessary to conduct optimization and specific research on insufficient areas, such as maintenance and development of programs and signature systems for visitors, and continuous development of historical and cultural network platforms by combining on-site surveys. Basic data should be provided for reference on the street.

Preservation and Utilization Plan of Sangju Yibugok Earthen Fortification Ruin (상주 이부곡토성 유적의 보존 및 활용방안)

  • JANG Choonghee
    • Korean Journal of Heritage: History & Science
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    • v.56 no.2
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    • pp.222-243
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    • 2023
  • In this study, we looked at how to preserve and use the Yibugok earthen fortification ruin in Sangju, which has recently been actively investigated and researched. Now that the coronavirus pandemic has become a reality, a utilization plan using local historical and cultural resources can be the starting point for regional revitalization. To this end, this study first reviewed the historical value of the Sangju Yibugok earthen fortification. The historical and cultural resource value of the fortification was reviewed in recent archaeological achievements along with the results of existing literature research, and distortion in its utilization was avoided. Next, an analysis of the perception of the demand class and local residents, the subject of utilization, was conducted with visitor statistics and surveys. This is because empathy for historical and cultural resources by the demand class and local residents, who are the main agents of utilization, is the most important factor in the use of cultural assets. Based on the theoretical review presented above, the use cases of ancient fortification ruins were examined in the last chapter 4, and a utilization plan for the fortification was presented focusing on empathy. This study was conducted with a focus on the historical value of the use of the fortification ruins, the empathy of the demand class, and the public. In order to overcome the crisis in Sangju, a high-risk area due to population decline, various measures must be proposed, and establishing historical and cultural identity at the center of Sabeolguk and enhancing its image through various utilization measures can be one of the alternatives.

A study on the biographical records and meritorious certification awarded to Jeong In-Kyung in Koryo Dynasty (고려 후기 정인경의 정책과 공신록권의 분석)

  • 여은영;남권희
    • Journal of Korean Library and Information Science Society
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    • v.21
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    • pp.485-528
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    • 1994
  • The aim of this study is to analyze biographical records and Meritorious Certification of Jeong In-Kyung. The analysis is made in the respects of : 1) Bibliographical analysis of the (SeoSan Jeongshi GaSeung) 2) Biographical study of Jeong In-Kyung 3) Historical and Political background in the period of king ChungYeul The summary of this study is as follows: 1. The

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