• 멤브레인
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• 제2권2호
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• pp.104-111
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• 1992

A curved channel duct is designed, built and used specifically to produce Dean vortices as a result of flow around a $180^{\circ}C$ curve. We present evidence using optical reflection of the existmace of the vortices in the curved section and following flat section. Also, three different feed soludons(DI water, a monodispersed styrene-divinyl-benzene latex particle suspension and a yeast suspension) were used to determine the effectiveness of Dean instabilities to destabilize polarization layers. For each suspension, the flux data were compared as a function of time for flow conditions with and without Dean vortices, for a $0.2{\mu}m$ microfiltration membrane. Any permeation flux improvement was not sustained for $2.0De_c$ due to the vortex-decay in the flat section after the curved channel, but a 15~30% permeation improvement was obtained for $3.8De_c$.

• Nuclear Engineering and Technology
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• 제34권4호
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• pp.370-381
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• 2002

The neutron induced nuclear data for Pr-141, Nd-143, Nd-145, Sm-147 and Sm-149 were calculated and evaluated from 10 keV to 20 MeV. The energy dependent optical model potential parameters were extracted based on the recent experimental data and applied up to 20 MeV. The s-wave strength function was calculated. Spherical optical model , statistical model in equilibrium energy, multistep direct and multistep compound model in pre-equilibrium energy and direct capture model were introduced in Empire calculation. The theoretically calculated cross sections were compared with the experimental data and the evaluated files. The model calculated total and capture cross sections were in good agreement with the reference experimental data. The capture cross sections in pre-equilibrium were enhanced in recent released Empire version. The evaluated cross section results were compiled to ENDF-6 format and will improve the ENDF/B-Vl.

• ETRI Journal
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• 제43권5호
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• pp.775-786
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• 2021

To translate in real time, a simultaneous translation system should determine when to stop reading source tokens and generate target tokens corresponding to a partial source sentence read up to that point. However, conventional attention-based neural machine translation (NMT) models cannot produce translations with adequate latency in online scenarios because they wait until a source sentence is completed to compute alignment between the source and target tokens. To address this issue, we propose a reinforced learning (RL)-based attention mechanism, the reinforced attention mechanism, which allows a neural translation model to jointly train the stopping criterion and a partial translation model. The proposed attention mechanism comprises two modules, one to ensure translation quality and the other to address latency. Different from previous RL-based simultaneous translation systems, which learn the stopping criterion from a fixed NMT model, the modules can be trained jointly with a novel reward function. In our experiments, the proposed model has better translation quality and comparable latency compared to previous models.

• Journal of Yeungnam Medical Science
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• 제36권3호
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• pp.163-182
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• 2019

The primary function of intraoperative frozen consultation is to provide an as accurate and prompt diagnosis as possible during surgery and to guide the surgeon in further management. However, the evaluation of frozen section (FS) is sometimes difficult because of suboptimal tissue quality and frozen artifacts compared with routinely processed tissue section. The pathologist responsible for the FS diagnosis requires experience and good judgment. Ovarian tumors are a heterogeneous group of tumors including primary surface epithelial tumors, germ cell tumors and sex cord-stromal tumors, secondary tumors, and other groups of tumors of uncertain histogenesis or nonspecific stroma. Intraoperative FS is a very important and reliable tool that guides the surgical management of ovarian tumors. In this review, the diagnostic key points for the pathologist and the implication of the FS diagnosis on the operator's decisions are discussed.

• Coupled systems mechanics
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• 제12권1호
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• pp.69-81
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• 2023

This paper considers a delamination analysis of a statically undetermined inhomogeneous beam structure of rectangular section with viscoelastic behavior under torsion. The beam is built in at its two ends. The beam has two longitudinal inhomogeneous layers with a delamination crack between them. A notch is made in the upper crack arm. The external torsion moment applied on the beam is a function of time. Under these conditions, the beam has one degree of indeterminacy. In order to derive the strain energy release rate, first, the static indeterminacy is resolved. Then the strain energy release rate is obtained by analyzing the balance of the energy with considering the viscoelastic behavior. The strain energy release rate is found also by analyzing the compliance of the beam for checkup. Solution of the strain energy release rate in a beam without a notch in the upper crack arm is derived too. In this case, the beam has two degrees of static indeterminacy (the torsion moment in the upper crack arm is treated as an additional internal redundant unknown). A parametric investigation of the strain energy release rate is carried-out.

• BMB Reports
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• 제33권5호
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• pp.407-411
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• 2000

The effects of heat shock, or all-trans retinoic acid, on the expression of the C-reactive protein mRNA in the HT-29 human colon carcinoma cells, as well as the functional role of the C-reactive protein as a molecular chaperone, were studied. The expression level of the C-reactive protein mRNA in the HT-29 cells was increased time-dependently when exposed to heat-shock, and dose-dependently when treated with all-trans retinoic acid. The activities of transglutaminase C and K in the HT-29 cells were significantly increased when treated with all-trans retinoic acid. The C-reactive protein prevented thermal aggregation of the citrate synthase and stabilized the target enzyme, citrate synthase. The C-reactive protein promoted functional refolding of the urea-denatured citrate synthase up to 40-70%. These results suggest that the C-reactive protein, which is induced in human colon carcinoma cells, when heated or treated with all-trans retinoic acid has in a part functional activity of the molecular chaperone.

• 항공우주시스템공학회지
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• 제13권2호
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• pp.51-59
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• 2019

이번 연구에서는 앞서 Part I [1]에서 수행한 단일-셀(single-cell) 모델에 이어, 시위 방향으로 비대칭성 단면을 가지는 다중-셀(multi-cell) 복합재료 박벽보(thin-walled beam) 모델을 선정하여, 단면의 형상에 대한 이론적인 동특성을 해석하였다. 이를 위해 와핑 구속 효과와 전단 변형 효과, 보의 테이퍼비와 단면비 등을 고려하였다. Part I에서와 마찬가지로 다중-셀 단면의 질량 및 강성 계수와 고유 진동수 등의 특성을 조사하였다. 특히, 다중-셀과 단일-셀 단면을 비교하고, 다중-셀 단면의 고유 진동수에 미치는 테이퍼비와 단면비의 영향을 비교 분석하였다. 또한, 단면의 비대칭성과 와핑 함수를 보정하지 않은 경우에 대해 그 결과를 비교하였다.

• Korean Journal of Radiology
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• 제1권2호
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• pp.79-83
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• 2000

Objective: To describe the thin-section CT findings of arc-welders' pneumoconiosis. Materials and Methods: Eighty-five arc-welders with a three to 30 (mean, 15)-year history of exposure underwent thin-section CT scanning. The extent of abnormalities detected was correlated with the severity of dyspnea and pulmonary function tests. For comparison, images of 43 smoking males (mean 25 pack-year) who underwent thin-section CT for other reasons (smokers' group) were also analyzed. Results: Fifty-four welders (63.5%) and six smokers (14.0%) showed positive findings. Predominant thin-section CT findings were poorly-defined centrilobular micronodules (30/54, 55.6%), branching linear structure (18/54, 33.3%), and ground-glass attenuation (6/54, 11.1%). In the smokers' group, poorly-defined micronodules were found in four patients, branching linear structures in one, and ground-glass attenuation in one. In welders, the extent of abnormalities seen on thin-section CT showed no significant correlation with the severity of dyspnea or the results of pulmonary funotion test. Conclusion: Poorly-defined centrilobular micronodules and branching linear structures were the thin-section CT findings most frequently seen in patients with arc-welders' pneumoconiosis. Less commonly, extensive ground-glass attenuation was also seen.

• 대한교통학회지
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• 제26권3호
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• pp.17-29
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• 2008

통행지체함수는 도로상의 교통량과 통행시간과의 관계를 나타내는 함수로 통행자들의 경로선택행위를 모형화한 통행배정(traffic assignment)모형에 주로 사용되고 있으며, 이를 위해서는 기본적으로 통행지체함수를 현실에 맞게 정산해야 한다. 본 연구는 기종점 통행자료를 구축하는 과정에서 중요한 역할을 하는 통행지체함수(volumedelay function)의 파라미터를 추정하고, 검증하는데 연구의 목적이 있다. 이를 위하여 본 연구에서는 전구간을 탐색하는 열거법에 황금분할법(golden section method)을 결합시켜 효율적으로 해를 찾는 방법을 제시하였으며 몇 가지 검증지표를 이용하여 현재 사용하고 있는 파라미터와 비교 분석하였다. 분석을 위하여 2006년 국가교통DB의 기종점 통행량(OD) 및 네트워크와 2006년 도로교통량 통계연보 자료를 이용하였으며, 분석결과 새롭게 추정된 파라미터값이 좀 더 현실적임을 보여 주었다.

• Journal of applied mathematics & informatics
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• 제20권1_2호
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• pp.585-594
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• 2006

We consider a stochastic integral process represented by multiple Ito-Wiener integrals. We derive gaussian chaos which has some shift continuous function. We get continuity property of self-similar process represented by multiple integrals and finally we show that $Y_{H_t}$ (t) is continuous in t with probability one for Holder function $H_t$ of exponent $\beta$.