• Title/Summary/Keyword: 완화현상

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Coverage Modeling in Neural Machine Translation using Orthogonal Regularization (직교 정규화를 이용한 신경망 기계 번역에서의 커버리지 모델링)

  • Lee, Yo-Han;Kim, Young-Kil
    • Annual Conference on Human and Language Technology
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    • 2018.10a
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    • pp.561-566
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    • 2018
  • 최근 신경망 번역 모델에 주의 집중 네트워크가 제안되어 기존의 기계 번역 모델인 규칙 기반 번역 모델, 통계적 번역 모델에 비해 높은 번역 성능을 보이고 있다. 그러나 주의 집중 네트워크가 잘못 모델링되는 경우 과소 번역 현상이 나타난다. 신경망 번역 모델에 커버리지 메커니즘을 추가하여 과소 번역 현상을 완화하는 연구가 진행되었으나 이는 모델의 구조를 변경해야하는 불편함이 있다. 본 논문에서는 신경망 번역 모델의 구조를 변경하지 않고 새로운 손실 함수를 정의하여 과소 번역 현상을 완화하는 방법을 제안한다. 한-영 번역 실험을 통해 제안한 주의 집중 네트워크의 정규화 방법이 커버리지 메커니즘의 목적을 효율적으로 달성함을 보인다.

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Analysis of Stress Relaxation Behaviors of Geosynthetics (지오신세틱스의 응력완화거동 해석)

  • Jeon, Han-Yong
    • Journal of the Korean Geosynthetics Society
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    • v.5 no.3
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    • pp.31-36
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    • 2006
  • In this study, stress relaxation behaviors of nonwoven geotextile and geomembrane which have protection, filtration and drainage, water barrier functions, respectively were examined. 'Theory of transition phenomen' was applied to interpretate the stress relaxation behaviors of two geosynthetics. The initial and later relaxation times for stress relaxation behaviors of geosynthetics were derived from the constitutive equations. The initial relaxation behaviors of these geosynthetics were dependent on the additional strains and were especially faster with temperature. Finally, both relaxation times of geosynthetics were shorter with additional strain and temperature and the reduction of relaxation times of nonwoven geotextile were larger than those of geomembrane.

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A Study on Coding Techniques for Flicker Reduction and BER Performance Improvement in Visible Light Communication (가시광통신에서 플리커 완화 및 BER 성능 향상을 위한 코딩 기법에 대한 연구)

  • Lee, Kyu-Jin
    • Journal of Convergence for Information Technology
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    • v.11 no.2
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    • pp.25-30
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    • 2021
  • In this paper, we studied the coding technique for flicker mitigation and BER performance improvement in visible light communication system. In order to increase the transmission speed of visible light communication, a multi-transmission multi-LED transmission system using a plurality of LEDs is being actively studied. However, when data is transmitted through N LEDs in a multi-LED visible light communication system using N LEDs, there is a continuous zero section in which 0 is transmitted simultaneously according to the data sequence, and since the transmission section of 1 is different, flickering Or, a phenomenon in which the dimming level changes occurs. The visible light communication system is a communication system that simultaneously performs communication and lighting functions. Therefore, transmission efficiency of communication and brightness of lighting must be considered at the same time. To solve this problem, we proposed a flicker reduction mapping that can alleviate flicker and dimming level problems, improve error detection and BER performance through coding mapping of each LED data sequence.

Analysis of Stress Relaxation Behaviors of Geosynthetics (토목 합성재료의 응력완화 거동 해석)

  • Jeon, Han-Yong;Park, Young-Mok;Chung, Jin-Gyo
    • Journal of the Korean Geosynthetics Society
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    • v.3 no.4
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    • pp.21-27
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    • 2004
  • Stress relaxation behaviors of nonwoven geotextile and geomembrane which have protection, filtration and drainage, water barrier functions, respectively were analyzed. 'Theory of transition phenomena' was applied to interpretate the stress relaxation behaviors of two geosynthetics. The initial and later relaxation times for stress relaxation behaviors of geosynthetics were derived from the constitutive equations. The initial relaxation behaviors of these geosynthetics were dependent on the additional strains and were especially faster with temperature. Finally, both relaxation times of geosynthetics were shorter with additional strain and temperature.

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An Econometric Analysis of Mitigating Urban Heat Island Effect with Urban Forest (계량경제적 접근을 통한 도시림의 도시열섬 완화효과 분석)

  • Kim, Dong-Hyeon;Kim, Eui-Gyeong;Yang, Jun-Seok;Kim, Hyeon-Geun;Shin, Hae-Jin
    • Journal of Korean Society of Forest Science
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    • v.100 no.1
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    • pp.79-87
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    • 2011
  • This study was conducted to identify the relationship between urban heat island effect and forest, analyzing electricity consumption model and temperature change model. Electricity consumption model was adopted to clarify a role of forests in alleviating the heat island effect at the national scale, while temperature change model was adopted to clarify a role of forests in mitigating urban heat island effect on metropolis with using econometric analysis. The analysis results from both models clearly show a negative correlation between the urban forests within living areas and heat island effect. In particular, when urban forests within living area per person increases by $1m^2$, the average municipal electricity consumption decreases by 0.02MWh and the summer daytime temperature for metropolitan cities decreases by $1.15^{\circ}C$.

Clinical Implementation of a Virtual-Micro MLC for Smoothing MLC Field Edge (다엽콜리메이터에 의한 조사경계면에서의 요동현상을 완화시켜주는 가상미세다엽콜리메이터의 임상 적용)

  • Cho Byung-Chul;Park Hee-Chul;Bae Hoonsik
    • Progress in Medical Physics
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    • v.15 no.3
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    • pp.167-172
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    • 2004
  • A Siemens HD-270 MLC$^{TM}$, a virtual-micro MLC, allows to the application of a smooth field edge method due to the finite leaf-width of MLC. This technique was implemented into a Pinnacle planning system in order to evaluate the dose distributions during the planning stage. The necessary dosimetric aspects, such as undulation and effective penumbra, were investigated with variations in the resolutions of a virtual-micro MLC and field edge angle. The positional accuracy of the couch movement was also assessed for clinical implementation. The overhead time for planning and treatment was confirmed as negligible.e.

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Ultrasonic Velocity and Absorption Measurements for poly (sodium 4-styrenesulfonate) and Water Solutions (Poly (sodium 4-styrenesulfonate)/ 물 이성분용액의 초음파 음속 및 흡수계수측정)

  • 배종림
    • The Journal of the Acoustical Society of Korea
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    • v.23 no.7
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    • pp.497-502
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    • 2004
  • Both ultrasonic velocity at 3 MHz and absorption coefficient in the frequency range of 0.2-2 MHz were measured for poly (sodium 4-styrenesulfonate) aqueous solution over the concentration range of 5 to 25 % by weight. Pulse echo overlap method was employed to measure the ultrasonic velocity over the temperature range of 10-90 ℃ and the high-a ultrasonic resonator method was used for the absorption coefficient measurement at 20 ℃. The velocity exhibited a maximum value at approximately 55. 59, 63. 67, and 71 ℃ in 25, 20. 15, 10. and 5 wt% solutions, respectively. The velocity increased with poly (sodium 4-styrenesulfonate) concentration at a given temperature. The concentrations dependences of the relaxation frequency and amplitude showed that the relaxation around 200 kHz is related to the structural fluctuations of polymer molecules, such as the segmental motions of the polymer chains and that around 1 MHz resulted from the proton transfer reaction of the oxygen sites of SO₃. Both the absorption and the shear viscosity increase with the Polymer concentration. but decrease with temperature.

Stress Relaxation Test of Granite under Water-Saturated Triaxial Condition (화강암의 응력완화현상에 관한 수침삼축시험)

  • 서용석
    • The Journal of Engineering Geology
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    • v.10 no.3
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    • pp.217-223
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    • 2000
  • Microcracks that consist of quarry planes of granite are an essential factor affecting the long-term behavior of granite. In this paper, fine-grained granite distributed in the Tsukuba area of Japan was selected and microcracks were measured by using scanline method. In addition, a new relaxation testing equipment was developed to carry out stress relaxation test under water-saturated triaxial condition. Based on the relaxation test results with the initial stress level of 75%, the axial stress is decreased by 39%-49% just after the start of the tests, and the totally relaxed stress is 10∼24 MPa in 190 ERT (Elapsed relaxation time, hour). In addition, the relaxed stress is increased with the density of cracks which are parallel to axial load direction.

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Linear Response Theory for the Mechanical Energy Relaxation of Solid High Polymers at Low Temperature (抵溫에서의 固體 重合體의 力學的 에너지 緩和에 對한 線形反應 理論)

  • Eu, Byung Chan
    • Journal of the Korean Chemical Society
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    • v.20 no.5
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    • pp.340-350
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    • 1976
  • Linear response theory is proposed to be applied for theoretical description of the phenomena in mechanical spectroscopy of solid high polymers below glass transition temperatures. The energy dissipation by sample is given in terms of certain time correlation functions. It is shown that the result leads to the result by Kirkwood on the energy loss and relaxation of cross-linked polymers, if the Liouville operator is replaced by the diffusion equation operator of Kirkwood. An approximation method of calculating the correlation functions is considered in order to show a way to calculate relaxation times. Using the approximation method, we consider a double-well potential model for energy relaxation, in order to see a connection between the present theory and a model theory used in mechanical energy relaxation phenomena of solid polymers containing pendant cyclohexyl groups at low temperature.

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