• Title/Summary/Keyword: Operational history

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Practical seismic assessment of unreinforced masonry historical buildings

  • Pardalopoulos, Stylianos I.;Pantazopoulou, Stavroula J.;Ignatakis, Christos E.
    • Earthquakes and Structures
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    • v.11 no.2
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    • pp.195-215
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    • 2016
  • Rehabilitation of historical unreinforced masonry (URM) buildings is a priority in many parts of the world, since those buildings are a living part of history and a testament of human achievement of the era of their construction. Many of these buildings are still operational; comprising brittle materials with no reinforcements, with spatially distributed mass and stiffness, they are not encompassed by current seismic assessment procedures that have been developed for other structural types. To facilitate the difficult task of selecting a proper rehabilitation strategy - often restricted by international treaties for non-invasiveness and reversibility of the intervention - and given the practical requirements for the buildings' intended reuse, this paper presents a practical procedure for assessment of seismic demands of URM buildings - mainly historical constructions that lack a well-defined diaphragm action. A key ingredient of the method is approximation of the spatial shape of lateral translation, ${\Phi}$, that the building assumes when subjected to a uniform field of lateral acceleration. Using ${\Phi}$ as a 3-D shape function, the dynamic response of the system is evaluated, using the concepts of SDOF approximation of continuous systems. This enables determination of the envelope of the developed deformations and the tendency for deformation and damage localization throughout the examined building for a given design earthquake scenario. Deformation demands are specified in terms of relative drift ratios referring to the in-plane and the out-of-plane seismic response of the building's structural elements. Drift ratio demands are compared with drift capacities associated with predefined performance limits. The accuracy of the introduced procedure is evaluated through (a) comparison of the response profiles with those obtained from detailed time-history dynamic analysis using a suite of ten strong ground motion records, five of which with near-field characteristics, and (b) evaluation of the performance assessment results with observations reported in reconnaissance reports of the field performance of two neoclassical torsionally-sensitive historical buildings, located in Thessaloniki, Greece, which survived a major earthquake in the past.

A Basic Study on the Koreanness of Contemporary Korean Landscape Architecture (한국 현대 조경의 한국성 논의를 위한 기초 연구)

  • Choi, Jung-Min;Choi, Key-Soo
    • Journal of the Korean Institute of Landscape Architecture
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    • v.35 no.4
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    • pp.1-15
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    • 2007
  • The purpose of this study is to mate a basic foundation for the discourse of Koreanness of contemporary Korean landscape architecture by way of searching the conceptual definitions of Koreanness through analysis of Koreanness discourses. The results are that discourses of Koreanness are to be classified in aesthetics type, spatial-temporal type, and cultural type. Aesthetics type is understood as style in terms of formal and design representation planning principles of spatial composition and immanence in terms of philosophy. Spatial-temporal type is understood as contemporaneity. This is classified as the concept of connoting of tradition, and separating and keeping a distance from tradition. Cultural type is prescribed as cultural identity. This is classified as unity, generality and individuality. The intension of Koreanness of these types is represented as an aspect changing and shifting from one regulation to another regulation. First, in the concerns of substantial archetypes like Korean original form, decorative element, spatial composition aesthetic perception and philosophy, Koreanness shifts to the point of view of contemporaniety which is created and defined in history. Second, Koreanness as contemporaniety shows a trend of shifting the point of view which is to be found through the reconsideration on modem history and modernism. Third, Koreanness defined as cultural identity shows a trend to emphasize the differences in other cultures and includes all the modem cultural agents. The number of views understood as individuality and denial are small but provide important points. Programmatic definition of Koreanness is not suitable. This basic study uses a stipulative or operational definition of Koreanness in many ways such as spatial and regional identity. Koreanness study for Korean contemporary landscape architecture requires a systematic understanding of modernity and colonization relating to identity. Also, it is needed to elaborate on the discourse to divide the meaning of a concept of identity.

A Study on the History of Princess Fashion and Its Socio-Cultural Implications -Focused on the Feminist's Viewpoint- (공주패션의 역사와 사회문화적 고찰 - 페미니스트 관점에서 -)

  • Kim, Sung-Bok
    • The Korean Fashion and Textile Research Journal
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    • v.6 no.6
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    • pp.723-730
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    • 2004
  • The purpose of this study is to speculate on the history and the meaning of so-called "princess fashion" based on the feminist's viewpoint. While many designers in Korean fashion world have fostered the trend of princess fashion, relatively little insight has been developed regarding its socio-cultural meanings. For this problem, the researcher traced the historical background and the development of the princess fashion in both the western and the Korean fashion world. As a case of the princess fashion study, Andre Kim(a renowned Korean designer)'s collection was selected and analyzed since he has often been a central figure for the princess fashion trends in Korea. Here the operational definition of the princess fashion is the lavish dresses designed based on the western court dress styles. As a result, the researcher found that the princess fashion was originated from the eighteenth century in France. In the nineteenth century, male designers took over the role to make extravagant dresses such as empire and crinoline dresses which became the prototypes for the princess fashion. In Korea, the western court dress style was introduced at the end of the nineteenth century and it became a uniform of prostitutes during the Korean War. By analyzing Andre Kim's collection, it is found that his romantic dresses imitated the nineteenth century court dresses. Therefore, from the feminist's viewpoint, his princess fashion is a mere reproduction of anachronistic styles reflecting inferior and passive images of women. The researcher draws a conclusion that today's fashion should transcend the princess fashion that signifies the female's submissive-masochistic roles operated by the male's sexual expectation.

Resonance Characteristics of a Arch Bridge for High-Speed Railways (고속철도 아치교량의 공진특성)

  • Nam, Deok Woo;Choi, Hong Kil;Kim, Kyoung Nam;Jung, Kyoung Sup
    • Journal of Korean Society of Steel Construction
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    • v.20 no.4
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    • pp.455-467
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    • 2008
  • The dynamic vehicle running tests were performed to analyze dynamic behavioral characteristics such as displacement, strain history loop and vibration acceleration in arch bridges. Also, the validity of the modeling was verified by comparing the results of the tests and those of the structural analysis modeling. With the resonance revision of verified modeling, when the ratio of excited frequencies to natural frequencies exceeds ${1{\pm}0.04}$, the stability of the bridge is obtained. Also, in the event of resonance by speed parameter, the second mode shape is dominant to the dynamic behaviors of arch bridges. It is found that manipulating the parameters involving arch ribs can increase the second mode natural frequency. It makes critical velocity greater than operational velocities to guarantee the stability of arch bridges.

A Study on the Improvement of Freedom of Information Act (「정보공개법」 개선방안 연구)

  • Kim, Youseung;Jung, Jinim
    • The Korean Journal of Archival Studies
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    • no.81
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    • pp.45-87
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    • 2024
  • This study aims to discuss ways to improve the information disclosure system centered on the Freedom of Information Act by analyzing the revision history of the Act and interviewing information disclosure experts. First, the study analyzed the revision history and contents of the Act from its enactment to today. It found that although positive amendments have been made in terms of expanding the right to know, they have been limited to operational aspects, and no amendments have been made to the criteria for determining information subject to disclosure. The interview was organized into three areas: achievements, problems, and improvements of the Act. The analysis was conducted by breaking down the content of each area and organizing it into themes. In conclusion, the study proposed eight recommendations for improvement, including expanding the scope of information disclosure, categorizing the information to be disclosed, securing a procedure for appealing the non-disclosure of information, increasing the effectiveness of the committee, introducing penalties and disciplinary regulations, establishing an Information Disclosure Appeals Tribunal, establishing systematic controls to prevent misuse of the right to request information, and merging the Public Data Act with the Freedom of Information Act.

A Study on the AtoN Operational Software Development for the AtoN Management and the Decision Support of its Placement Planning (항로표지 관리 및 배치 의사결정 지원을 위한 항로표지 운용 소프트웨어 개발에 관한 연구)

  • Kim, Ah-Young;Lee, Yeong-Ju;Park, Se-Kil;Oh, Jae-Yong;Kim, Yeon-Gyu
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.20 no.5
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    • pp.543-551
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    • 2014
  • This study has searched to find a program in order to manage simply and practically use the expelled AtoN database from the AtoN Simulator and to support the idea decision for the AtoN placement. It examines a program that manages AtoN database through the hierarchy structure, history card and endowment with condition same as a scenario. And accomplishes this study's goal owing to realizing AtoN operational software that helps for visual, hearing sense, fixed amount verification upon AtoN placement project. The AtoN operational software contributes not only flexible control like a newly establishment, relocation etc, but also supports idea decision for AtoN placement plan through many functions such as condition search, virtual sailing and fixed amount appraisal result exhibition, etc. Through utilization of this, it is to help upon the presupposition of the impact to ship or sailor about many designs and in addition, upon the judgment of whether or not for the efficiency and appropriation of the design. It is expected to reduce possible failure costs and management costs due to AtoN design and placement plans, because to compare more various designs thru the easier verification method.

A Study on the User Perception for the Operational Plan Following the Establishment of the Okcheon-gun Daily Life Culture and Sports Center Library (옥천군 생활문화체육센터 도서관 건립 후 운영 방안을 위한 이용자 인식조사 연구)

  • Kwak, Seung-Jin;Noh, Younghee;Kang, Bong-Suk;Ko, Jae Min;Kim, Jeong-Taek;Kwak, Woojung
    • Journal of the Korean Society for information Management
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    • v.39 no.2
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    • pp.87-110
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    • 2022
  • This study was conducted based on the need to establish an operational plan following the establishment of the Okcheon-gun Daily Life Culture and Sports Center Library, and for the users of public libraries in Okcheon-gun, the functions and roles of the Okcheon-gun Library, collection related to operational direction, user service related activation, library usage related status survey, preference for the future use and perception of desired services were surveyed. Based on the results of the perception survey, the direction required by the Okcheon-gun residents for the Library was identified, and the research results are as follows. As a result of the study, first, when establishing a collection plan, the data types ought to be based on the printed materials and the multi-media materials to reflect the needs of the users, and it may also be necessary to collect them in consideration of the subject areas including literature, art, history, and technical sciences. Second, to provide various information services, it would be necessary to establish an overall information service plan, and it was identified that it would be necessary to develop various information services according to the user preferences and provide cooperative services. Third, it was determined that the programs appropriate for the various subjects and age groups should be continuously expanded moving forward in consideration of the larges demand for programs by the residents of Okcheon-gun. Fourth, new constructions and spatial improvements are needed, and the overall preference for open spaces was significant. In the case of cultural space, the preference for youth cultural facilities, convenience facilities for residents, infinite loss of imagination, and the (experiential) exhibition halls turned out to be large.

Analysis of Hierarchical Competition Structure and Pricing Strategy in the Hotel Industry

  • BAEK, Unji;SIM, Youngseok;LEE, Seul-Ki
    • The Journal of Asian Finance, Economics and Business
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    • v.6 no.4
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    • pp.179-187
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    • 2019
  • This study aims to investigate the effects of market commonality and resource similarity on price competition and the recursive consequences in the Korean lodging market. Price comparison among hotels in the same geographic market has been facilitated through the development of information technology, rendering little search cost of consumers. While the literature implies the heterogeneous price attack and response among hotels, a limited number of empirical researches focus on the asymmetric and recursive pattern in the competitive dynamics. This study empirically examines the price interactions in the Korean lodging market based on the theoretical framework of competitive price interactions and countervailing power. Demonstrating superiority to the spatial lag model and the ordinary least squares in the estimation, the results from spatial error model suggest that the hotels with longer operational history pose an asymmetric impact on the price of the newer hotels. The asymmetry is also found in chain hotels over the independent, further implying the possibility of predatory pricing. The findings of this study provide the evidence of a hierarchical structure in the price competition, with different countervailing power by the resources of the hotels. Theoretical and managerial implications are discussed, with suggestions for future study.

Root Cause Analysis on the Steam Turbine Blade Damage of the Combined Cycle Power Plant (복합화력발전소 증기터빈 동익 손상 원인분석)

  • Kang, M.S.;Kim, K.Y.;Yun, W.N.;Lee, W.K.
    • Journal of Power System Engineering
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    • v.12 no.4
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    • pp.57-63
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    • 2008
  • The last stage blade of the low pressure steam turbine remarkably affects turbine plant performance and availability Turbine manufacturers are continuously developing the low pressure last stage blades using the latest technology in order to achieve higher reliability and improved efficiency. They tend to lengthen the last stage blade and apply shrouds at the blades to enhance turbine efficiency. The long blades increase the blade tip circumferential speed and water droplet erosion at shroud is anticipated. Parts of integral shrouds of the last stage 40 inch blades were cracked and liberated recently in a combined cycle power plant. In order to analyze the root cause of the last stage blades shroud cracks, we investigated operational history, heat balance diagram, damaged blades shape, fractured surface of damaged blades, microstructure examination and design data, etc. Root causes were analyzed as the improper material and design of the blade. Notches induced by erosion and blade shroud were failed eventually by high cycle fatigue. This paper describes the root cause analysis and countermeasures for the steam turbine last stage blade shroud cracks of the combined cycle power plant.

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Overview of chronic fatigue syndrome (만성 피로 증후군)

  • Sin, Ho-Cheol
    • Journal of Korea Association of Health Promotion
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    • v.3 no.1
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    • pp.97-109
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    • 2005
  • Chronic fatigue syndrome(CFS) is a complex, debilitating disorder characterized by at least 6 months of severe persistent of relapsing fatigue and a group of characteristic but nonspecific symptoms. Many researchers have proposed that CFS has a specific cause. However currently no evidence exists that proves either a specific cause of CFS. And there is no diagnostic test for CFS. The diagnosis of chronic fatigue syndrome is based on the patient's history, excluding other illnesses In the absence of consistent biological markers, the diagnosis of CFS arises from operational criteria that do not afford validity. The prognosis is poor and often disability and impairment of daily function and performance are prolonged. A limited understanding of the CFS has complicated the management of this disorder. Therefore, treatment of CFS may be variable and should be tailored to each patient. Therapy should include exercise, diet, good sleep hygiene, antidepressants, and other medications, depending on the patient's presentation. Regular follow-up is key to continue to exclude other medical problems and provide support for patients. Chronic fatigue syndrome is a challenging illness to manage and requires a team approach of caring providers. For the majority of patients this is a chronic illness with the goals of therapy being to improve functional status and to prevent disability. Further understanding of the etiology and pathogenesis of this illness should lead to better specific therapy.

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