• 제목/요약/키워드: Defense-in-Depth

검색결과 185건 처리시간 0.025초

동해 울산 연안해역 SSDP-105 심부코어 지점의 지음향 모델 (Geoacoustic Model at the SSDP-105 Long-core Site of the Ulsan Coastal Area, the East Sea)

  • 양우헌;이광수;한주영
    • 한국지구과학회지
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    • 제39권2호
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    • pp.154-163
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    • 2018
  • 지음향 모델은 수중과 해저 음파의 전파에 영향을 미치는 해저 지층의 물성과 음향 특성을 포함한다. 이 연구는 동해 남서부 내대륙붕에 위치한 울산 해역의 SSDP-105 시추 지점에서 심부 지층의 지음향 모델을 처음으로 제시하였다. 수심 79 m의 연안 퇴적 지층에서 52 m 심도의 3개 지음향 모델을 구성하였다. 지음향 모델은 연구 해역의 SSDP-105 심부시추 코어 자료와 스파커 탄성파 단면 자료에 근거한다. 실제 모델링을 위해, 모델의 지음향 특성값은 Hamilton 모델링 방법을 이용하여 해저면 하부 현장 심도의 특성값으로 보정하였다. 이 지음향 모델은 동해 울산 연안해역에서 심부 지층의 지음향 특성을 반영하는 중 저주파수 지음향/수중음향 실험을 위해 활용될 것이다.

Analysis of Hydraulic Characteristics According to the Cross-Section Changes in Submerged Rigid Vegetation

  • Lee, Jeongheum;Jeong, Yeon-Myeong;Kim, Jun-Seok;Hur, Dong-Soo
    • 한국해양공학회지
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    • 제36권5호
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    • pp.326-339
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    • 2022
  • Recently, not only Korea but also the world has been suffering from problems related to coastal erosion. The hard defense method has been primarily used as a countermeasure against erosion. However, this method is expensive and has environmental implications. Hence, interest in other alternative methods, such as the eco-friendly vegetation method, is increasing. In this study, we aim to analyze the hydraulic characteristic of submerged rigid vegetation according to the cross-sectional change through a hydraulic experiment and numerical simulation. From the hydraulic experiment, the reflection coefficient, transmission coefficient, and energy dissipation coefficient were analyzed according to the density, width, and multi-row arrangement of the vegetation zone. From numerical simulations, the flow field, vorticity distribution, turbulence distribution, and wave distribution around the vegetation zone were analyzed according to the crest depth, width, density, and multi-row arrangement distance of the vegetation zone. The hydraulic experiment results suggest that the transmission coefficient decreased as the density and width of the vegetation zone increased, and the multi-row arrangement condition did not affect the hydraulic characteristics significantly. Moreover, the numerical simulations showed that as the crest depth decreased, the width and density of vegetation increased along with vorticity and turbulence intensity, resulting in increased wave height attenuation performance. Additionally, there was no significant difference in vorticity, turbulence intensity, and wave height attenuation performance based on the multi-row arrangement distance. Overall, in the case of submerged rigid vegetation, the wave energy attenuation performance increased as the density and width of the vegetation zone increased and crest depth decreased. However, the multi-row arrangement condition did not affect the wave energy attenuation performance significantly.

원자력 발전소의 화재 안전계획에 관한 연구 (A Study on The Fire Safety Design of Nuclear Power Plants in Korea.)

  • 김운형
    • 한국화재소방학회논문지
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    • 제5권3호
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    • pp.15-22
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    • 1991
  • It has been generally accepted that nuclear power (NPP) is suiable for power supply in korea because of its economical profits and pollution-free energy. When designing or operating a NPP. The main points to be home in mind are the hazards of and protection against an uncontrolled release of the large quantities of radioactiv substances which are always generated in a nuclear reactor while it is in iperation. Multiple independent safety systems are provided which should prevent this from occurring. Thus fire prevention measures in NPP follow the “Defense-in-depth” concept. This study aims to suggest the fire prevention measures and to demonstrate information which is needed for NPP planning and its safety assessment. The findings of this study can be used as useful data for fire protection plannings at the first phase of NPP design.

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Beliefs about Physical Activity in Sedentary Cancer Patients: an In-depth Interview Study in France

  • Falzon, Charlene;Chalabaev, Aina;Schuft, Laura;Brizzi, Christophe;Ganga, Marion;d'Arripe-Longueville, Fabienne
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권12호
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    • pp.6033-6038
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    • 2012
  • This study was designed to identify beliefs about physical activity in cancer patients. Semi- structured interviews were conducted with 20 patients under treatment, who were invited to identify perceived barriers for not adopting a physically active lifestyle and to express their beliefs about physical activity. Content analyses revealed five main categories of beliefs including four types of barriers: (a) barriers related to the side effects of treatment; (b) barriers related to a lack of perceived physical abilities; (c) barriers related to a lack of interest for physical activity; (d) beliefs about the negative effects of physical activity, and (e) beliefs about the positive effects of physical activity. These findings extend the existing literature by indicating how stereotypes may play a role in explaining sedentary lifestyles in cancer patients.

Geological Safety Evaluation and Monitoring of Nuclear Facility Sites in South Korea

  • Lee, Hyunwoo;Woo, Hyeon Dong;Chun, Hyun Ju;Im, Chang-Bock
    • 지질공학
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    • 제24권4호
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    • pp.609-613
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    • 2014
  • The Korean Peninsula, located at the southeastern tip of the Eurasian Plate, is known to be tectonically stable, and no critical evidence has yet been found that would override the safety design of nuclear facilities in South Korea. Because a nuclear power plant, like other major social overhead capital facilities, could cause great damage to both the environment and society through an unexpected tectonic event, even one of extremely low probability, like the Fukushima accident, a defense-in-depth safety approach is required in geological and geotechnical site safety evaluation for nuclear projects. This paper introduces the regulatory procedures that are in place to confirm nuclear site safety and site monitoring (e.g., earthquakes and groundwater) systems applied to nuclear facilities in order to reduce inherent uncertainties within the site safety review of geological and seismological issues related with a NPP project.

CTD Data Processing for CREAMS Expeditions: Thermal-lag Correction of Sea-Bird CTD

  • Kim, Kuh;Cho, Yang-Ki;Ossi, Hyong;Kim, Young-Gyu
    • Journal of the korean society of oceanography
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    • 제35권4호
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    • pp.192-199
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    • 2000
  • Standard CTD data processing recommended by Sea-Bird Electronics produced thermal-lag corrections larger than 0.1 psu for the data taken during the CREAMS expeditions in the northern part of the East/Japan Sea where a vertical temperature gradient frequently exceeds 1.0$^{\circ}$C/m in the upper 100 m near the sea surface. As the standard processing is based upon a recursive filter which was introduced by Lueck and Pickle (1990), coefficients of the recursive filter have been newly derived for the CREAMS data by minimizing the difference between salinities of downcast and upcast in temperature-salinity domain. The new coefficients are validated by comparison with salinities measured by a salinometer, AUTOSAL 8400B. An accurate correction for the thermal-lag is critical in identifying water masses at intermediate depth in the East/japan Sea.

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절충교역을 통해 획득한 연구개발 기술의 활용성과 분석 (An Analysis of Application Performance of Defense R&D Technologies Acquired by Offset Programs)

  • 홍석수;서재현;심상렬
    • 기술혁신연구
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    • 제22권2호
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    • pp.1-30
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    • 2014
  • 우리나라는 1980년대 초 절충교역 제도를 도입하여 국가 경제발전 및 국방 전력증강의 수단으로 활용하고 있으며 2010년까지 백억 달러가 넘는 가치를 절충교역으로 획득하였다. 그러나 한편으로 그간 절충교역 제도의 실효성에 대해 지속적으로 의문이 제기되어온 것이 사실이다. 현실적으로 절충교역을 통해 획득한 기술의 성과를 객관적으로 분석, 산출한다는 것은 매우 어려운 과제이며 이에 따라 정량적인 성과분석은 매우 제한적으로 이루어지고 있는 실정이다. 따라서 본 연구에서는 보다 깊이 있는 성과분석을 통하여 절충교역활용 현황을 파악하고 이를 기반으로 향후 절충교역 제도의 발전방향을 제안하였다. 먼저, 기존 성과분석 관련 문헌조사를 통해 절충교역 성과분석을 위한 조사지표를 도출하여 설문서를 작성하였으며, 각 수혜기관, 업체를 대상으로 조사를 실시하였다. 또한 각 군, 정부기관 및 연구소, 업체 소속 절충교역 분야 전문가를 대상으로는 정성적인 측면에서 제도의 성과, 실효성에 대한 설문을 실시하여 그 결과를 분석하였다. 그리고 최근 3개년 동안의 사업에서 획득한 기술들을 대상으로 DEA 기법을 활용하여 성과 창출의 효율성을 살펴보았다. 성과분석 및 설문조사 결과, 공통적으로 기술적 측면에서는 긍정적인 성과가 있었으나 경제적인 부분에서는 성과가 상대적으로 저조했으며 설문결과도 이와 동일한 것으로 나타났다. 이를 토대로 절충교역 제도는 신정부의 정책방향에 발맞춰 기존 핵심기술 획득 위주의 정책에서 대 중소기업 상생, 방위산업 활성화를 통한 국가경제 기여를 위해 그 추진방향의 전환이 필요한 것으로 판단된다.

크라우드소싱 커뮤니티 내 고객 선호와 조직 수용 아이디어 간 비교 연구 (A Comparative Analysis between Organization-Adoptable and User-Favorable Ideas in a Crowdsourcing Community)

  • 이한준;서소영;서용무
    • Asia pacific journal of information systems
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    • 제24권1호
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    • pp.51-64
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    • 2014
  • Open innovation concept is advocating the importance of the customer roles in firm's innovation. As a result, crowdsourcing community is drawing attention as a strategic asset for open innovation across diverse industries. Considering that the goal of crowdsourcing community is harnessing innovative ideas, understanding the characteristics of user-favorable and organization-adoptable ideas can enhance the effectiveness and efficiency of idea crowdsourcing. In our approach, we extracted idea content-based characteristics such as subjectivity, negativity, prosocialness, and depth of idea to examine what are the factors that affect user preference and organizational adoption. An analysis of 71,134 ideas from MyStarbucksIdea.com shows that there are significant differences between user-favorable and organization-adoptable ideas in terms of idea characteristics. Lastly, both theoretical and managerial implications are discussed.

조직 차원의 정보보안 전략의 개념 (Concept of Strategy in Organizational Information Security)

  • 박상서
    • 융합보안논문지
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    • 제7권3호
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    • pp.15-24
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    • 2007
  • 정보보안의 중요성에 관한 인식이 증가함에 따라 다양한 보안대책이 조직에 도입되고 있다. 하지만 대부분의 경우 이들 보안대책은 전략적으로 운영되지 않고 있다. 따라서 본 논문은 조직에서의 정보보안 전략은 무엇인가에 대해 개념적으로 연구한다. 이를 위하여 다양한 문헌에서 정보보안 전략이 어떻게 소개되었으며, 어떠한 전략이 제시되어 왔는지 연구한다. 본 논문은 조직의 정보보안에 있어서의 전략 자체에 초점을 맞추어, 개념을 정립하고, 지금까지 제시되어 온 다양한 전략을 식별하여 체계적으로 분류하였다는데 의의가 있다.

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FRENCH PROGRAM TOWARDS AN INNOVATIVE SODIUM COOLED FAST REACTOR

  • Martin, Ph.;Anzieu, P.;Rouault, J.;Serpantie, J.P.;Verwaerde, D.
    • Nuclear Engineering and Technology
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    • 제39권4호
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    • pp.237-248
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    • 2007
  • Sodium-cooled fast reactor is considered in France as a potential candidate for a prototype of 4th generation system to be built by 2020. A detailed working program has been launched recently to identify by 2012 the potential improvement tracks for later industrial development of these reactors. The goals for innovation are first identified: Progress of the safety with a special attention to severe accidents risk minimization and mitigation (defense in depth approach); Economic competitiveness of the system mainly by reducing the capital cost, the investment risks by enhancing in service inspection and repair capacities, and raising the availability; Sustainability with fissile material management while reducing the proliferation risk; capacity for long-lived waste transmutation.