• Title/Summary/Keyword: 전이과정

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Redox Property of Transition Metal Oxides in Catalytic Oxidation (TPR/TPO 실험기법을 이용한 전이금속산화물의 산화-환원 특성 연구)

  • Kim, Young-Ho;Lee, Ho-In
    • Applied Chemistry for Engineering
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    • v.10 no.8
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    • pp.1161-1168
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    • 1999
  • The redox property of oxide materials of the 3rd period transition metals(Cr~Zn), V, Mo, and W was studied with temperature-programmed reduction/temperature-programmed oxidation(TPR/TPO) experiment. The peak temperatures of TPO spectra were equal to or lower than those of TPR spectra. And the peak shapes of TPO spectra were broader than those of TPR ones. The activation energies of TPR/TPO for the oxides of the 3rd period transition metals showed in the range of 33~149 kJ/mol, while for the oxides of V, Mo, and W, they showed relatively higher values. The change of activation energies of TPR/TPO with various metal oxides showed a similar trend to the change of their metal-oxygen bond strengths. The change of activation energies of o-xylene oxidation for various metal oxides was proportional to the difference (${\Delta}E_a$) between the activation energy of TPR and that of TPO. From these results, we concluded that the oxidation of o-xylene over various metal oxide catalysts follows the Mars-van Krevelen mechanism including the surface reduction-oxidation of the metal oxide itself.

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Synthesis of Asynchronous Circuits from Deterministic Signal Transition Graph with Timing Constraints (시간 제한 조건을 가진 결정성 신호 전이 그래프로부터 비동기 회로의 합성)

  • Kim, Hee-Sook;Jung, Sung-Tae
    • Journal of KIISE:Computer Systems and Theory
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    • v.27 no.2
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    • pp.216-226
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    • 2000
  • This paper presents a new method to synthesize timed asynchronous circuits directly from the specification without generating a state graph. The synthesis procedure begins with a deterministic signal transition graph specification with timing constraints. First, a timing analysis extracts the timed concurrency and timed causality relations between any two signal transitions. Then, a hazard-free implementation under the timing constraints is synthesized by constructing a precedence graph and finding paths in the graph. The major result of this work is that the method does not suffer from the state explosion problem, achieves significant reductions in synthesis time, and generates circuits that have nearly the same area as compared to previous methods.

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Environment, Drivers and Dynamics of Socio-technical System Transition and STI Policy for the Transition Management

  • Park, Sang-Ook
    • Journal of Science and Technology Studies
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    • v.11 no.1
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    • pp.61-88
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    • 2011
  • This paper presents theoretical discussions on socio-techical system transition, by shedding light on the STS context. With a rising attention paid by STI policy researchers, the socio-technical system perspective seems particularly promising in applying to the pursuit for the sustainable development. The normative strand in STI policy research has been strongly influenced by the STS tradition that emphasizes active and participatory roles not only of academian but also of science and technology. Throughout reviewing the development of the socio-technical system perspective, its theoretical components of environment, drivers and dynamics are discussed, often being linked to older perspectives. STI policy involves in socio-technical transition in a manner of transition management and governance, which is the final part of this paper.

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Test of homogeneity for transition probabilities in panel Markov chains (패널 마코프 체인의 전이확률에 대한 동질성 검정)

  • Lee, Sung Duck;Jo, Na Rae
    • The Korean Journal of Applied Statistics
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    • v.30 no.1
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    • pp.147-157
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    • 2017
  • The test of transition probabilities in panel Markov chains are introduced. We deal with the hypotheses whether panel Markov chains have the same transition probabilities or not for all times. We suggest a LR test statistic for the test and its limit distribution is derived. We perform a simulation study to examine the limit distribution of test statistics when the number of the individuals are large.

A Note on Series Approximation of Transition Density of Diffusion Processes (확산모형 전이확률밀도의 급수근사법과 그 계수)

  • Lee, Eun-Kyung;Choi, Young-Soo;Lee, Yoon-Dong
    • The Korean Journal of Applied Statistics
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    • v.23 no.2
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    • pp.383-392
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    • 2010
  • Modelling financial phenomena with diffusion processes is frequently used technique. This study reviews the earlier researches on the approximation problem of transition densities of diffusion processes, which takes important roles in estimating diffusion processes, and consider the method to obtain the coefficients of series efficiently, in series approximation method of transition densities. We developed a new efficient algorithm to compute the coefficients which are represented by repeated Dynkin operator on Hermite polynomial.

A Pilot Study on Automatic Diagnosis of Cancer Cells Metastasis in Frozen Section Using Convolutional Neural Network (합성곱 신경망을 이용한 동결절편의 암세포 전이 여부 자동진단에 관한 예비연구)

  • Jung, Dae-Il;Kang, Jae-Ku;Jeon, Hye-Lynn;Oh, Se-Jong;Kim, Sungchul;Kim, Young-Gon;Gong, Gyungyub;Song, In Hye;Park, So Yeon;Ahn, Soomin;Lee, Hyunna;Yang, Dong Hyun;You, Wonsang
    • Proceedings of the Korea Information Processing Society Conference
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    • 2020.05a
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    • pp.480-482
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    • 2020
  • 동결절편검사는 수술과 연계하여 암 전이 여부를 판단하기 위한 응급한 병리검사가 필요할 때 이용된다. 합성곱 신경망은 이미지 분류에 뛰어난 성능을 보이는 딥러닝 기법으로 본 논문에서는 이를 이용하여 유방암 전이 여부를 자동적으로 진단하는 방법을 제안한다. 실험과정은 전처리, 학습, 후처리의 과정으로 구성되어 있으며, 합성곱 신경망으로는 Resnet-18 모델을 사용하였다. 실험결과 예측 정확도 및 종양의 최대 길이 정합 여부를 점수로 환산하여 약 0.514 의 결과를 보였다.

The Examination of gender differences in the process of intergenerational transmission of marital instability (결혼불안정성의 세대간의 전이과정에 있어서의 성차에 관한연구)

  • 김은경
    • Journal of Families and Better Life
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    • v.16 no.2
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    • pp.41-52
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    • 1998
  • The purpose of this research was to assess gender differences in the processes of intergenerational transmission of marital instability. This study revealed gender differences in the intergenerational transmission of marital instability. The fit indices suggest that the hypothesized model fit better for the female sample. Parental divorce marital quality and marital commitment were significant predictors of marital instability for both genders. Parental divorce was a strong predictor of marital quality for women only. While the path between age difference and marital quality for females was strong the same association disappeared for their male counterparts.

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State Transition Analysis Using Multiple-Valued Logic Automata and Genetic Algorithm (다치오토마타와 유전자 알고리즘에 의한 상태 전이 해석)

  • 고현정;손창식;정환묵
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2004.04a
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    • pp.506-509
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    • 2004
  • 생물과 같이 외부 환경의 변화에 적응하는 능력을 갖도록 하기 위한 시스템을 다치오토마타를 사용하여 모델화하고 이들에 대하여 도태, 교배, 돌연변이 둥의 유전적 조작을 반복함 적용에 의해 유한 상태 전이 과정을 해석하고 응용할 수 있는 방법을 제안한다. 이러한 해석과 방법에 대한 모델을 기초로 자기 갱신할 수 있는 자율 오토마타와 환경에 적응할 수 있는 적응 오토마타를 실현하는 기초 단계로 적용할 수 있는 가능성을 제안한다.

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The Effect of Cognitive Ability on Training and Transfer Performance (인지 능력이 훈련 및 전이 수행에 미치는 효과)

  • Jung Hong Chun;Lee Kyung Soo;Lee Suji;Jang Joo Young;Lee Hye Seung;Koo JaYoung;Sohn Young Woo
    • Korean Journal of Cognitive Science
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    • v.16 no.4
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    • pp.287-303
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    • 2005
  • This study examined the effect of cognitive ability levels on skill acquisition and transfer as a function of training difficulty. Participants were classified into three groups based on the result of cognitive ability tests. They were trained with difficult or easy tasks and then transferred to novel difficult tasks. Results suggest that cognitive ability levels influenced training performance, though the effect of training difficulty on transfer performance varied with cognitive ability. The training difficulty was most effective for those who have the medium level of cognitive ability. These results were discussed with respect to individual differences and skill transfer performance.

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Shallow Gas Exploration in the Pohang Basin Transition Zone (포항분지 전이대에서 천부가스 탐사)

  • Lee, Donghoon;Kim, Byoung-Yeop;Kim, Ji-Soo;Jang, Seonghyung
    • Geophysics and Geophysical Exploration
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    • v.25 no.1
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    • pp.1-13
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    • 2022
  • For surveying shallow gas reservoirs in the Pohang basin, we proposed a seismic exploration method applicable to the transition zone in which land and marine areas are connected. We designed the seismic acquisition geometry considering both environments. We installed land nodal receivers on the ground and employed vibroseis and airgun sources in both land and marine areas. For seismic exploration in the transition zone, specific acquisition and processing techniques are required to ensure precise matching of reflectors at the boundary between the onshore and offshore regions. To enhance the continuity of reflection events on the seismic section, we performed amplitude and phase corrections with respect to the source types and applied a static correction. Following these processing steps, we obtained a seismic section showing connected reflectors around the boundary in the transition zone. We anticipate that our proposed seismic exploration method can also be used for fault detection in the transition zone.