• Title/Summary/Keyword: City-State

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Comparative Experiments to Assess the Effects of Accumulator Nitrogen Injection on Passive Core Cooling During Small Break LOCA

  • Li, Yuquan;Hao, Botao;Zhong, Jia;Wang, Nan
    • Nuclear Engineering and Technology
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    • v.49 no.1
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    • pp.54-70
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    • 2017
  • The accumulator is a passive safety injection device for emergency core cooling systems. As an important safety feature for providing a high-speed injection flow to the core by compressed nitrogen gas pressure during a loss-of-coolant accident (LOCA), the accumulator injects its precharged nitrogen into the system after its coolant has been emptied. Attention has been drawn to the possible negative effects caused by such a nitrogen injection in passive safety nuclear power plants. Although some experimental work on the nitrogen injection has been done, there have been no comparative tests in which the effects on the system responses and the core safety have been clearly assessed. In this study, a new thermal hydraulic integral test facility-the advanced core-cooling mechanism experiment (ACME)-was designed and constructed to support the CAP1400 safety review. The ACME test facility was used to study the nitrogen injection effects on the system responses to the small break loss-of-coolant accident LOCA (SBLOCA) transient. Two comparison test groups-a 2-inch cold leg break and a double-ended direct-vessel-injection (DEDVI) line break-were conducted. Each group consists of a nitrogen injection test and a nitrogen isolation comparison test with the same break conditions. To assess the nitrogen injection effects, the experimental data that are representative of the system responses and the core safety were compared and analyzed. The results of the comparison show that the effects of nitrogen injection on system responses and core safety are significantly different between the 2-inch and DEDVI breaks. The mechanisms of the different effects on the transient were also investigated. The amount of nitrogen injected, along with its heat absorption, was likewise evaluated in order to assess its effect on the system depressurization process. The results of the comparison and analyses in this study are important for recognizing and understanding the potential negative effects on the passive core cooling performance caused by nitrogen injection during the SBLOCA transient.

Smart Cities: A Review of the Most Recent Literature (스마트시티: 최근 문헌에 대한 리뷰)

  • Hoffman, Mark C.
    • Informatization Policy
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    • v.27 no.1
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    • pp.3-35
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    • 2020
  • Interest in smart cities is growing; information and communication technology, urban planning, urban economy development, health, and many other areas are intertwined within smart city research and practice. The definition of smart city is evolving, and its vagueness is sometimes confusing. This review of the smart city literature tries to capture the big picture of this big idea. This review places into context work done since 2016, as earlier work is well reviewed in Albino (2015) and Cochia (2014). First is a review of the various smart city definitions. Second, an inventory of terms related to or subsumed by the smart city label are presented. Third, outcomes of indexes created to measure a city's smartness are presented. Fourth, the taxonomies used to organize the disparate content that falls under the smart city umbrella are discussed. Fifth, the most recent literature associated with six commonly recognized subgenres, namely smart economy, smart governance, smart living, smart people, smart environment, and smart mobility are reviewed. Sixth, important critiques of the smart city idea are presented.

Utilizing Spatial-data to Provide for U-Service Based on U-GIS

  • Lee, Seok-Ho;Lee, Ji-Yeong;Kim, Hyong-Bok
    • Spatial Information Research
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    • v.17 no.4
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    • pp.405-416
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    • 2009
  • According to the changes of the city's paradigm, the demand on u-City increases rapidly. u-City has been built at 54 areas in Korea (as of May 2009). One of the important determinants of success or failure in the increasing of u-City is how to provide u-Services. Most current u-Services are Sensor Network-based monitoring services to manage urban infrastructure. u-GIS is one of fundamental requirements to implement 'any time and any where' u-Service which covers the essential meaningful term "ubiquitous". Hence, in this paper, we 1) describe the definition of the spatial awareness, 2) discuss how to converge (Spatial Embedding) among different spatial data : topographic spatial data, sensor spatial data, and more, 3) bring forth an advanced form of u-Service, 4) analyze the state-of-the-art u-GIS techniques.

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Alberti's Theory of Architectural Design and Vitruvius (알베르티의 건축 설계론과 비트루비우스)

  • Cho, Eun-Jung
    • The Journal of Art Theory & Practice
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    • no.9
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    • pp.195-215
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    • 2010
  • Alberti's De re aedificatoria is the earliest case in the history of Italian Renaissance architectural treatises dealing with recovery of antiquity through textual and archaeological pursuits. The key source of the Renaissance theoreticians was Vitruvius' De architectura. However, Alberti was keenly aware of inaccuracy and Hellenization of Latinity in this classical text, and tried to compensate them in his own treatise. Furthermore he claimed a reformed discipline of the architects as well as the patrons, and prescribed how future buildings and cities should be built, based on the proper authority of ancient architecture in proper and intelligible Latin. Such an adaptation of classical usage in order to reestablish a modern norm preceded in his earlier work Momus, a satire on the contemporary Italian society of his own by following the model of Lucian. Alberti's suggestion of proper government in Momus's phrase was expanded in De re aedificatoria, for he consider the buildings are subject to the rules of morality and public interests. He proclaimed that the nature of beauty is the reasoned harmony of every part within a body, and architectural beauty also lies on the harmonized arrangement of all the elements within an individual building and of all individual buildings and facilities within a city. For the architects to execute this task, he formulated the concept of lineanenta, the form derived from the mind in order to prescribe the proper place, numbers, scale, and orders for whole building structure. It is the future oriented city-plans and building designs to serve the public interest and the good of all the individual citizens who make up the City-State that Alberti pursued in his treatise.

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A Study on Basic Plan Establishment of a Public Library in Busan Metropolitan City Hall: Focused on the Analysis of Library Current State in Government Office and Citizen's Perception in Busan (부산시청사 내 공공도서관 기본계획 수립을 위한 조사연구 - 국내 공공청사 내 도서관 현황과 부산지역 시민인식조사를 중심으로 -)

  • Kang, Eun Yeong
    • Journal of Korean Library and Information Science Society
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    • v.51 no.3
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    • pp.411-437
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    • 2020
  • Recently, public libraries as complex cultural spaces are becoming a trend, and public libraries as complex facilities that are built in one building or one site are being highlighted. This can be seen as part of a policy to expand public libraries as part of the government's Living SOC project. The establishment of libraries in government office is also included in this movement. Therefore, this study presented excellent cases by investigating the current state of government office in Korea and investigated citizens' perception on the establishment of public libraries in Busan Metropolitan City Hall. Based on this, a basic plan for the operation of public libraries in Busan Metropolitan City Hall, including basic directions, organization and manpower, collection development, and service programs (including specialization program), was proposed.

Analysis of Standardization Trend and Marketability with Tele-screen Service Platform for Smart City Foundation (스마트 시티 구축을 위한 텔레스크린 서비스플랫폼 표준화동향 및 시장성 분석)

  • Park, Sehwan;Choi, Yongsu
    • The Journal of the Convergence on Culture Technology
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    • v.1 no.2
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    • pp.71-75
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    • 2015
  • Smart City for establishing mutual communication for next-generation digital signage technology attracting attention in the tele screen service is being spread. In recent years, the state of the surrounding circumstances of the user-to-user information such as situation-based, bi-directional communication by collecting and analyzing the possible interactive tele-screen services. This study suggests the value of smart city services platform, standardization trends, domestic, and international marketability analysis information. Tele-screen service technology is able to be a high-level administrative services, and further domestic e-government technology can be spread all over the world.

Field Case Study on Regeneration of Decaying Ex-factory area in a Creative City 「Bologna」 (창조도시 볼로냐의 쇠퇴공장지역 재생 현지사례연구)

  • Lee, Yeunsook;Yoon, Hyegyung;Soo, Kabsoo
    • KIEAE Journal
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    • v.8 no.3
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    • pp.51-59
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    • 2008
  • response to the global city. It was developed to cope with the decline of the manufacturing industry, a rise in unemployment and a welfare state system in danger. In cities of the concept, there has been much change in existing urban space and accordingly wisdoms and knowledge has been accumulated. The purpose of this research is to scrutinize urban spatial modification of a regenerated model city "Bologna". The target area of analysis was a ex-factory ailing district. Field site visit, deep interview with professionals and citizens, walk through observation, and historial literature review on the site were employed. As results, its history, retrofit process and current change were systematically described. The results showed ways of thinking, attitude toward historic preservation, technology, and creativity of using existing buildings for contemporary functions. This has a significant implication on Korean urban development which mostly, has ignored the existing value of community and buildings.

Evaluation on the Environment Amelioration Functions of Green Spaces in Chongju City by GIS (지리정보체계를 이용한 청주시 녹지의 환청개선 기능 평가)

  • Koh, Kang Suk;Suh, Min Hwan;Kim, Jung Hyun;Kim, Kee Dae;Kil, Ji Hyun;Kim, Jeong Soo;Lee, Myung Woo
    • Journal of Environmental Impact Assessment
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    • v.8 no.1
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    • pp.51-59
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    • 1999
  • This study was conducted to evaluate the functions of green spaces for the environment amelioration in Chongju City. The results obtained from this study were as follows; 1. Total amounts of $SO_2$ and $NO_2$ which can be absorbed by green spaces in Chongju City from EPA model were calculated as 27,655 tons and l,551 tons per year, respectively. 2. It was estimated that more green spaces were needed to mitigate the effect of air pollutants emitted from industrial complex at Songjung-Dong, Bokdae-Dong and Sachang-Dong in Chongju City. This is acquired as a result of overlaying the map of administrative district, forest state, and $SO_2$ isoline using GIS method. 3. The amounts of green spaces and the selection of their proper location have to be considered at the stage of city planning and in this case, the amounts of air pollutants are also considered.

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A Study on the Relativity Between the Theatre's Composition Principle and Urban Concept - Focused on the Productions that are Applied for International Ideas Competition for the Design of the Seoul Performing Arts Center - (극장의 구성 원리와 도시 개념의 상관성에 관한 연구 - Seoul Performing Art Center 국제 공모전을 중심으로 -)

  • Lim Jong-Yup;Kwon Ik-Hyun
    • Korean Institute of Interior Design Journal
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    • v.15 no.1 s.54
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    • pp.47-54
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    • 2006
  • Stages, in the theatrical spaces, were space, which incorporates aspects of cities. Hence, the stages have been constituted to materialize sequence of city, which has exact number, proportion and order of ideal city. In addition, it has accomplished change, which depends on type of performance with the social condition and culture of generation, city has. However, the original form of theatrical space were forgotten on account of the various changes of theatrical form with modem movement since the end of 19th century, and theatrical space, which does not relate with its space of city, was started to constitute. Particularly in contemporary society, the theatre can give vitality to the citizens, and also theatrical architecture as a commercial code has been a general form, though it takes important role, which improves cultural value with technical improvement of cities development of society. Thus, this study analyzed urbanity ,which theatres have incorporated historically, and deduced a correlativity from to be based on constitution of space in visual, perceptual, spatial constitution and functional role. Focused on published SPAC international competition, it was interpreted by contemporary focus, therefore, this experiment suggests constitution of theatrical spaces of information, takes urbanity, through to analyze visual, perceptual, spatial constitution and functional role in context of contemporary city.

A Study on the Identifying Core Strategies for Urban Regeneration in Old Planned City - Focusing on Wolpi-dong, Ansan - (노후화된 계획도시 도시재생사업의 핵심전략 도출에 관한 연구 - 안산시 월피동을 중심으로 -)

  • Jo, Byung-Sun;Lee, Kang-jun
    • Journal of Urban Science
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    • v.12 no.1
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    • pp.11-20
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    • 2023
  • In the 1960s, planned cities were developed to solve urban issues aroused from rapid urbanization and industrialization. But as time goes by, planned cities are not playing their existed role. As the paradigm of the city has changed over the years from quantitative expansion to qualitative growth, it is resulted to focus more on urban regeneration rather than development. However, most urban regeneration took place mainly in the self-generated old cities. The purpose of this study is to reveal the validity of a project for urban regeneration in old planned city by examining its necessity and possibility. Focusing on the case of Ansan as representative planned city and Wolpi-dong as area of new deal project for urban regeneration, this study examines the historical background and analyzes the current state of Ansan to identify core strategies of project for urban regeneration.