• 제목/요약/키워드: INVISIBLE SYSTEM

검색결과 183건 처리시간 0.031초

베이스플레이트식 체결장치의 앵커볼트 설계 (Design of anchor-bolt for the rail fastening system with baseplate)

  • 김은;장승엽;조용진
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2006년도 추계학술대회 논문집
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    • pp.508-513
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    • 2006
  • Anchor bolt in baseplate fastenings on the slab track is an important component to conform placing and safety of fastenings. Due to the way of load transmission control of fastenings, sometimes anchor bolt has to be applied lateral load. So we have to take care for it when we design. Especially, in the case of anchor bolt which is applied loads repeatedly, we have to consider fatigue failure. If parts of machine are damaged in static loads, stress will exceed the yield strength. So parts could be transformed largely. Therefore because they are visible to the naked eyes, we can replace parts before failure. However, because fatigue failure that are invisible to the naked eyes happen unexpectedly, it's very dangerous. To make a reasonable design of anchor bolts, we will analyze them by changing diameters of anchor bolt, quality of insert, initial gap between anchor bolt and insert, the presence of insert, etc. which affect the stresses of anchor bolts. We can get the maximum and minimum amplitude of stress through the modified Goodman diagram or Smith diagram which represents limit of all strengths and stress components to the average stress. We also tried to show the way of examining the expected th life of anchor bolt briefly through considering above.

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학술정보 콘텐츠 제공을 위한 모바일 보안 서비스에 관한 연구 (Mobile Security for Academic Information Service)

  • 김상국;최병선;강무영
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2008년도 춘계 종합학술대회 논문집
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    • pp.473-476
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    • 2008
  • 모바일 네트워크 환경은 언제 어디서나 네트워크를 사용하는 모바일 서비스를 편리하게 사용할 수 있도록 해준다. 그러나 모바일 단말기의 제약과 기존 무선 네트워크 환경의 보안 문제로 인하여 많은 보안 취약점을 가지고 있다. 이에 본 논문에서는 국내 모바일 표준 플랫폼인 WIPI에 세션키와 공개키를 조합함으로서 최소한의 암/복호화 연산을 수행하는 방식으로 PKI 서비스 구조를 제안하였다. 제안된 국내 표준 암호 알고리즘 기반의 안전한 인증 시스템은 모바일 네트워크 보안에 더욱 견고함을 더하여 줄 것이고, 향후 KISTI의 모바일 학술정보 콘텐츠 제공에 있어 안전한 서비스를 제공할 것이다.

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ESR detection of optically-induced hyperpolarization of nitrogen vacancy centers in diamond

  • An, Min-Gi;Shim, Jeong Hyun;Kim, Kiwoong;Oh, Sangwon;Jeong, Keunhong
    • 한국자기공명학회논문지
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    • 제24권1호
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    • pp.9-15
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    • 2020
  • Nitrogen vacancy center (NV center) in diamond has recently been appeared as a promising candidate for hyperpolarization applications due to its optical pumping property by laser. Optically Detected Magnetic Resonance (ODMR) has been used as a conventional method to obtain the resonance spectrum of NV centers. ODMR, however, has a shortcoming of sensitivity and a limitation of subjects, such that the degree of hyperpolarization can hardly be estimated, and that the spins other than NV centers are invisible. In contrast, Electron Spin Resonance (ESR) spectroscopy is known to proportionally reflect the degree of spin polarization. In this work, we successfully observed the optically-induced hyperpolarization of NV spins in diamond through CW-ESR spectroscopy with an X-band system. All the NV peaks were identified by calculating the eigenvalues of NV spin Hamiltonian. The intensities of NV peaks were enhanced over 240 times after optical pumping. The enhanced peaks corresponding to the transition from |ms=0> to |ms=-1> revealed inverted phases, while other peaks remained in-phase. The optically-induced hyperpolarization on NV spins can be a useful polarization source, leading to 13C nuclear hyperpolarization in diamond.

수치지형정보를 애용한 지형의 3차원 표현 software 개발 (Development of the Three Dimensional Landform Display Software Using the Digital Terrain Model)

  • 이규석
    • 한국조경학회지
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    • 제17권3호
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    • pp.1-8
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    • 1990
  • The digital terrain model (DTM) or digital elevation model (DEM) is commonly used in representing the continuous variation of relief over space. One of the most frequent applications is to display the three dimensional view of the landform concerned. In this paper, the altitude matrices-regular grid cell format of the elevation in Mt. Kyeryong National Park were used in developing the three dimensional view software for the first time in Korea. It required the removal of hidden lines or surfaces. To do this, it was necessary to identify those surfaces and line segments that are visible and those that are invisible. Then, only the visible portions of the landform were displayed. The assumption that line segments are used to approximate contour surfaces by polygons was used in developing the three dimensional orthographic view. In order to remove hidden lines, the visibility test and masking algorithms were used. The software was developed in the engineering workstation, SUN 3/280 at the Institute of Space Science and Astronomy using 'C' in UNIX operating system. The software developed in this paper can be used in various fields. Some of them are as follows : (1) Landscape design and planning for identifying viewshed area(line of sight maps) (2) For planning the route selection and the facility location (3) Flight simulation for pilot training (4) Other landscape planning or civil engineering purposes

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휘도-색차 신호 기반의 컬러 영상 디지털 워터마킹 (Color Image Digital Watermarking based on a Luminance-Chrominance Signal)

  • 서정희;임영진;한은영;박흥복
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2006년도 춘계종합학술대회
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    • pp.565-568
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    • 2006
  • 휘도-색차 신호에서 휘도 신호는 그레이 영상을 생성하고, 각각의 컬러 요소들을 단색 시스템으로 호환할 수 있다. 그리고 휘도-색차 신호의 각 컬러 요소들은 적은 상관 관계를 가지므로 신호를 부호화 또는 변조하는데 유용성을 지닌다. 그러나 각 컬러 신호들은 통계적으로 적은 상관 관계를 가지나 서로 독립적이지는 않다. 그러므로 본 논문은 컬러 요소들 간의 상호 의존적인 특징을 고려하여 웨이브릿 기반의 주파수 영역에서 휘도-색차 신호에 대한 워터마크 삽입 알고리즘을 제안한다. 따라서 디지털 워터마크의 견고성과 비시각성을 보장할 수 있다.

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Influence of Fe(110) Substrate with strong On-site Coulomb Repulsion on the Electronic Structure of Single Cobalt Tetraphenylporphyrin: Scanning Tunneling Microscopy Study

  • 오영택;정호균;서정필;김효원;전상준;김성민;유재준;국양
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2009년도 제38회 동계학술대회 초록집
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    • pp.94-94
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    • 2010
  • Scanning tunneling microscopy (STM) was used to study the electronic structure of cobalt(II) tetraphenylporphyrin (CoTPP) on the Fe/W(110) substrate. Clover-like conformation of CoTPP was observed and showed bias dependent STM images. The central Co(II) ion of this porphyrin was protruded on the positive biases, but it was depressed on the negative biases. On the positive biases, the phenyl rings of CoTPP appeared to be bright contrary to the invisible pyrrole rings. These results were compared the first-principles calculations using GGA and GGA+U to elucidate the influence of the Fe substrate. GGA+U results agreed well with the experimental results; however, GGA did not. These results show that proper treatment of the on-site Coulomb repulsion of the Fe ions is crucial to describe the electronic structure of this system. By the comparison between the GGA+U calculations on the Fe substrate and the gas phase calculations, it can be noted that chemical potential shift occurred accompanying charge transfer from the Fe ions of the substrate to the pyrrole ligand of the porphyrin.

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교감 이론으로서 메를로퐁티의 '상호 엮임' (Merleau-Ponty's Intertwining as a Theory of Communion)

  • 권택영
    • 영어영문학
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    • 제57권4호
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    • pp.581-598
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    • 2011
  • The recent revival of phenomenology and aesthetics is deeply connected to the development of neuroscience which studies the nervous system and the brain with particular regard to cognition and memory. How are those fields gathered into building up the basis for the communication not only between human beings but also between humanity and its environment? This paper examines the human mind considered unseparable from the body, with reference to Merleau-Ponty's two major works: Phenomenology of Perception (1962) and The Visible and the Invisible (1968). While reading these texts, I investigate the way he overturns the Cartesian cogito and establishes the body as the ground of perception. According to him, human perception is chiefly obtained through the body rather than consciousness. Influenced by William James, who produced the unique concept of cognition and memory through his experiments with the brain, Merleau-Ponty extends Heideggerian Desein to the field of the embodied mind. James also anticipates Bergson, who regards memory as the product of interaction between consciousness and matter (or the body). The intervention of the body which stores the past experiences makes it impossible for us to capture the present moment in itself. This failure, however, is viewed as positive by Merleau-Ponty because the human body is not only a medium of social interaction, but also that of ecological communion.

The Influence of Intellectual Capital Elements on Company Performance

  • EKANINGRUM, Yulliana
    • The Journal of Asian Finance, Economics and Business
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    • 제8권1호
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    • pp.257-269
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    • 2021
  • Intellectual capital is becoming a crucial factor for a firm's long-term profit and performance in the knowledge-based economy as more firms identify their core competence as invisible assets rather than visible assets (Itami, 1987). The company was encouraged to measure financial and non-financial factors, including the customer perspective groups, the internal business process, learning and growth perspective, then to link all these measurements in a coherent system. This paper seeks to investigate the influence of intellectual capital elements on company performance, as well as the relationship among intellectual capital elements from a cause-effect perspective. Resource-Based View (RBV) considers intellectual capital as resource and capability to sustain competitive advantage on company performance. The partial least squares approach is used to examine listed banks in Indonesia Stock Exchange for year 2017-2019. Results show that human capital directly has positive influences on innovation capital, customer capital, and process capital. Innovation capital has positive, but less significant influence on process capital, which in turn influences customer capital. Human capital and process capital also influence customer capital. Finally, customer capital contributes to performance. This study helps management to identify relevant intellectual capital elements as competitive advantage and their indicators to enhance business performance.

박막형 압전 센서를 활용한 사질토 지반 지중 응력 측정 방법론 (Methodology to Measure Stress Within Sand Ground Using Force Sensing Resistors)

  • 김동균;우상인
    • 한국지반공학회논문집
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    • 제40권2호
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    • pp.115-123
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    • 2024
  • 응력은 비가시 물리량이므로, 지반 내부에서 이를 측정하기 위해서는 토압계가 필요하다. 기존의 스트레인 게이지 기반 토압계는 큰 강성을 가지며, 이는 지반 내부 응력을 교란시켜 토압 측정의 정확성에 영향을 준다. 박막형 압전센서는 얇고 유연하므로, 이를 활용할 경우 지반 내부 응력의 교란을 최소화하여 지중응력을 측정할 수 있다. 본 연구에서는 박막형 압전 센서를 활용하여 지반 내부의 응력을 측정하기 위한 시스템을 구축하였다. 박막형 압전 센서를 교정하기 위한 챔버를 제작하여 사질토 지반 내부에 매설된 박막형 압전 센서의 측정 변동성과 센서의 감지 영역에 부착된 퍽으로 인한 측정 토압의 재현성 향상을 반복실험을 통해 확인하였다.

디자인 방법론의 역사적 맥락에 대한 연구 - 사이보그 과학과의 관계를 중심으로 - (A Study on a Historical Context of the Design Methodology Movement With an Emphasis on Its relations to Cyborg Sciences)

  • 박해천
    • 디자인학연구
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    • 제19권5호
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    • pp.105-118
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    • 2006
  • 디자인사의 일반적인 관점에 따르면, 디자인 방법론은 모더니즘 디자인과 관계 속에서 해석되곤 한다. 본 논문은 제 2차 세계 대전 이후 군사 전략.테크놀로지의 연구 과정에서 성장한 사이보그 과학과의 관계에 초점을 맞춰, 디자인 방법론의 전개 과정을 고찰하고자 한다. 특히 그 관계는 크게 두 가지로 정의될 수 있다. 하나는 군사적인 연구 개발 프로젝트를 통해 정립된 오퍼레이션 리서치, 시스템 분석, 시스템 엔지니어링과 같은 시스템 과학이, 디자인의 과학화를 구호로 내걸었던 초기 디자인 방법론 운동에 의해 전유되는 과정이며, 다른 하나는 랜드 연구소를 근거지로 삼아 허버트 사이먼이 개진했던 "문제해결" 과 "인공지능"에 대한 이론들이 시스템 과학 이후의 디자인 방법론의 이론적 전개에 영향을 미치는 과정이다. 본 논문은 방법론 운동이 이와 같은 사이보그 과학과의 관계를 통해, 디자인 프로세스를 자본주의의 생산-소비 사이클의 피드백 루프로, 즉 시장의 보이지 않는 손을 가시화하는 정보 처리 과정으로 재정의 되는 과정을 살펴본다.

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