• 제목/요약/키워드: small shifts

검색결과 165건 처리시간 0.03초

잡음과 위치이동에 강인한 새로운 홍채인식 기법 (A Novel Iris recognition method robust to noises and translation)

  • 원정우;김재민;조성원;최경삼;최진수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 학술회의 논문집 정보 및 제어부문 B
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    • pp.392-395
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    • 2003
  • This paper describes a new iris segmentation and recognition method, which is robust to noises. Combining statistical classification and elastic boundary fitting, the iris is first segmented. Then, the localized iris image is smoothed by a convolution with a Gaussian function, down-sampled by a factor of filtered with a Laplacian operator, and quantized using the Lloyd-Max method. Since the quantized output is sensitive to a small shift of the full-resolution iris image, the outputs of the Laplacian operator are computed for all space shifts. The quantized output with maximum entropy is selected as the final feature representation. An appropriate formulation of similarity measure is defined for the classification of the quantized output. Experimentally we showed that the proposed method produces superb performance in iris segmentation and recognition.

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Fisheries Resources -A Brief Introduction of the Republic of Senegal

  • Mbengue, Modou
    • 한국해양바이오학회지
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    • 제3권1호
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    • pp.38-41
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    • 2008
  • Fish is a major source of protein for the Senegalese population. Fishing plays a dominant role in the Government's policy towards generating employment. It currently generates about 100,000 direct jobs (fishermen) for nationals, of which more than 90% are in small-scale fishing. The fishing industry also contributes to Government revenue through different agreements. In addition to associated dues, fishing agreements imply a series of economic, trade and technical counterparts. Under the latest fishing agreement concluded by Senegal and the European Union (1997-2001), direct financial compensation amounts to about CFAF 32 billion. Despite its economic and social importance, the sector has to face serious disequilibria both in resource exploitation and market supply: the coastal demersal (deep lying fish) stocks with high market value (mostly exported) are fully and even over-exploited, with a serious risk of local market supply shortages looming ahead as the fishing effort shifts from locally consumed species to export-oriented ones.

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디지털 헬스케어 생태계 활성화를 위한 라이프로그 공통데이터 참조모델 (A Lifelog Common Data Reference Model for the Healthcare Ecosystem)

  • 이영주;고윤석
    • 지식경영연구
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    • 제19권4호
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    • pp.149-170
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    • 2018
  • Healthcare lifelog, a personal record relating to disease treatment and healthcare, plays an important role in healthcare paradigm shifts in which medical and information technology converge. Healthcare services based on various healthcare lifelogs are being launched domestically by both large corporations and small and medium enterprises, however, they are being built on an individual platform that is dependent on each company. Therefore, the terms of lifelog data are different as well as the measurement specifications are not uniform. This study proposes a reference model for minimum common data required for sharing and utilization of healthcare lifelog. Literature study and expert survey derived 3 domain, 17 essential items, and 51 sub-items. The model provides definition, measurement data format, measurement method, and precautions for each detailed measurement item, and provides necessary guidelines for data and service design and construction for healthcare service. This study has its significance as a basic research supporting the activation of ecosystem by ensuring interoperability of data between heterogeneous healthcare devices linked to digital healthcare platform.

NMR Studies of Lipid-Protein Interaction in Apolipoprotein B / Phosphatidylcholine Recombinants

  • Byong-Seok Choi;Cheal O Joe;Ke Won Kang
    • Bulletin of the Korean Chemical Society
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    • 제11권3호
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    • pp.238-240
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    • 1990
  • $^{31}P${$^1H$} nuclear Overhauser effects (NOEs) have been obtained for complexes formed between apolipoprotein B (apo B) and dipalmytoylphosphatidylcholine (DPPC) vesicles. NOE measurements have been conducted with broad-band irradiation of the entire $^1H$ spectrum in order to identify the proton source of the NOE. In a unilamellar vesicle formed spontaneously upon mixing aqueous suspensions of long-chain phospholipid with small amount of short-chain lecithin, the maximum NOE occurs at the N-methyl proton resonance position of the choline moiety. With addition of cholesterol to vesicles, the position of the NOE maximum shifts further away from the choline methyl frequency. For the ternary apo B-vesicle-cholesterol complex, the position of the maximum NOE lies halfway between those in vesicles with and without cholesterol.

$^1H$ NMR Estimation of Multi-Redox potentials of Cytochrome $c_3$ from Desulfovibrio vulgaris Hildenborough

  • 박장수;강신원;최성낙
    • Bulletin of the Korean Chemical Society
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    • 제16권4호
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    • pp.331-336
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    • 1995
  • The macroscopic and microscopic redox potentials of tetrahemoprotein, cytochrome c3 from Desulfovibrio vulgaris(Hildenborough) (DvH) were estimated from 1H NMR and differential pulse polarography(DPP). Five sets of NMR resonances were confirmed by a redox titration. They represent cytochrome c3 molecules in five macroscopic redox states. The electron transfer in cytochrome c3 involves four consecutive one-electron steps. The saturation transfer method was used to determine the chemical shifts of eight heme methyl resonances in five different oxidation states. Thirty two microscopic redox potentials were estimated. The results showed the presence of a strong positive interaction between a pair of particular hemes. Comparing the results with those of Desulfovibrio vulgaris Miyazaki F (DvMF), it was observed that the two proteins resemble each other in overall redox pattern, but there is small difference in the relative redox potentials of four hemes.

Combined VSI EWMA Chart with Accumulate-Combine Method for Moderate or Small Shifts

  • Chang, Duk-Joon
    • 통합자연과학논문집
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    • 제15권1호
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    • pp.1-8
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    • 2022
  • In a multivariate normal production process Np(µ,Σ), a chart combining three EWMA charts with accumulate-combine method for µ, variance components of Σ, and off-diagonal elements of Σ, into a EWMA (exponentially weighted moving average) chart is considered, which is called a combined EWMA chart. Through simulation work, the proposed combined EWMA chart's numerical performance and properties are examined. The simulation results show that the proposed combined EWMA chart, which is simultaneously monitoring all the process parameters of multivariate normal production process, works effectively in the perspective of means, variances and correlation coefficients. In addition, the combined EWMA chart is extended to VSI chart.

Named entity recognition using transfer learning and small human- and meta-pseudo-labeled datasets

  • Kyoungman Bae;Joon-Ho Lim
    • ETRI Journal
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    • 제46권1호
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    • pp.59-70
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    • 2024
  • We introduce a high-performance named entity recognition (NER) model for written and spoken language. To overcome challenges related to labeled data scarcity and domain shifts, we use transfer learning to leverage our previously developed KorBERT as the base model. We also adopt a meta-pseudo-label method using a teacher/student framework with labeled and unlabeled data. Our model presents two modifications. First, the student model is updated with an average loss from both human- and pseudo-labeled data. Second, the influence of noisy pseudo-labeled data is mitigated by considering feedback scores and updating the teacher model only when below a threshold (0.0005). We achieve the target NER performance in the spoken language domain and improve that in the written language domain by proposing a straightforward rollback method that reverts to the best model based on scarce human-labeled data. Further improvement is achieved by adjusting the label vector weights in the named entity dictionary.

Doppler Shifts of the $H{\alpha}$ Line and the Ca II 854.2 nm Line in a Quiet Region of the Sun Observed with the FISS/NST

  • 채종철;박형민;양희수;박영득;조경석;안광수
    • 천문학회보
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    • 제37권2호
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    • pp.113.1-113.1
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    • 2012
  • The characteristics of Doppler shifts in a quiet region of the Sun are investigated by comparing between the $H{\alpha}$ line and the Caii infrared line at 854.2 nm. A small area of $16^{\prime\prime}{\times}40^{\prime\prime}$ was observed for about half an hour with the Fast Imaging Solar Spectrograph (FISS) of the 1.6 meter New Solar Telescope (NST) at Big Bear Solar Observatory. The observed area contains a network region and an internetwork region, and identified in the network region are $H{\alpha}$ fibrils, Caii fibrils and bright points. We infer the Doppler velocity from each line profile at a point with the lambdameter method as a function of half wavelength separation ${\Delta}{\lambda}$. It is confirmed that the bisector of the spatially-averaged Caii line profile has an inverse C-shape of with a significant peak redshift of +1.8 km/s. In contrast, the bisector of the spatially-averaged $H{\alpha}$ line profile has a different shape; it is almost vertically straight or, if not, has a C-shape with a small peak blueshift of -0.5 km/s. In both the lines, the bisectors of bright network points are much different from those of other features in that they are significantly redshifted not only at the line centers, but also at the wings. We also find that the spatio-temporal fluctuation of Doppler shift inferred from the Caii line is correlated with those of the $H{\alpha}$ line. The strongest correlation occurs in the internework region, and when the inner wings rather than the line centers are used to determine Doppler shift. In this region, the RMS value of Doppler shift fluctuation is the largest at the line center, and monotonically decreases with ${\Delta}{\lambda}$. We discuss the physical implications of our results on the formation of the $H{\alpha}$ line and Caii 854.2 nm line in the quiet region chromosphere.

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Intraspecific diet shifts of the sesarmid crab, Sesarma dehaani, in three wetlands in the Han River estuary, South Korea

  • Yang, Dongwoo;Han, Donguk;Park, Sangkyu
    • Journal of Ecology and Environment
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    • 제43권1호
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    • pp.31-42
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    • 2019
  • Background: Han River estuary is a national wetland reserve near the Demilitarized Zone (DMZ) between South Korea and North Korea. This trans-boundary estuary area has been well preserved and shows distinctive plant communities along the salinity gradient. To elucidate energy flows and nutrient cycling in this area, we studied trophic relations between the dominant sesarmid crab, Sesarma dehaani, and food sources in three wetlands with different environments along the estuarine gradients. Results: Stable isotope signatures (${\delta}^{13}C$ and ${\delta}^{15}N$) of the crabs were significantly different among the sites and body size classes. Seasonal changes in ${\delta}^{13}C$ of small crabs were distinct from those of large individuals at all the sites. The isotopic values and fatty acid profiles of the crabs were more different among the sites in September than in May. In May, large-sized crabs utilized more plant materials compared to other dietary sources in contrast to small-sized crabs as revealed by a stable isotope mixing modeling, whereas contributions to diets of crabs were not dominated by a specific diet for different body size in September except at site 1. Based on PCA loadings, fatty acid content of $18:3{\omega}3$, known as a biomarker of plant materials, was the main factor to separate size groups of crabs in May and September. The ${\delta}^{13}C$ value of sediment had high correlation with those of small-sized crabs at site 1 and 2 when 1-month time lag was applied to the value for crabs during the surveyed period. Conclusions: Based on the stable isotope and fatty acid results, the consumption habits of S. dehaani appear to be distinguished by sites and their size. In particular, smaller size of S. dehaani appears to be more dependent on fewer food sources and is influenced more by the diet sources from the sediments in Han River estuary.

동적패널모형을 활용한 서울시 중소형 오피스 빌딩 임대료 결정 요인 연구: CBD(도심권)와 GBD(강남권) 비교를 중심으로 (A Study of Rent Determinants of Small and Medium-Sized Office Buildings in Seoul Using a Dynamic Panel Model: Focusing on CBD and GBD Comparison)

  • 김나라;유진석;김종진
    • 토지주택연구
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    • 제14권4호
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    • pp.47-62
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    • 2023
  • 본 연구는 오피스의 소비재 및 투자재 특성을 고려하여 거시경제변수와 미시특성변수를 포함한 모형을 구성하고, 유효 임대료 자료를 기반으로 국내 주요 업무지구인 도심권과 강남권 중소형 오피스 빌딩 임대료 결정요인을 비교 분석하여 투자적 시사점을 제시하고자 하였다. 분석방법은 시계열자료와 횡단면자료를 함께 포함하여 분석이 가능하며, 추정량 편의 가능성이 낮은 것으로 알려진 동적패널모형을 사용하였다. 두 모형의 분석결과를 요약하면 다음과 같다. 도심권·강남권 중소형 오피스 빌딩 임대료 영향 요인 분석결과 변수와 계수값 부호 측면에서 도심권 분석 결과와 동일하게 나타났다. 따라서 도심권과 강남권 중소형 오피스 빌딩의 임대료는 건물 및 입지특성과 함께 거시경제환경의 변화에 의해 영향을 받는 것으로 나타나 공간 소비재와 투자재의 특성을 모두 가지는 시장으로 해석된다. 위의 분석결과를 바탕으로 투자적 측면의 시사점은 다음과 같이 제시된다. 첫째, 도심권에 위치한 입지는 양호하지만 노후화된 중소형 오피스 빌딩의 재건축은 현실적으로 한계가 있다. 따라서 이러한 중소형 오피스 빌딩의 가치는 지속적으로 낮아질 가능성이 높아질 수 있어 투자시 이에 대한 고려가 필요하다. 둘째, 도심권의 경우 주차여건이 가격에 큰 영향을 줄 수 있으므로 도심권 중소형 오피스 빌딩 투자시 대상 빌딩의 주차환경과 개선 가능성에 대한 고려가 중요하다고 할 수 있다. 마지막으로 강남권 중소형 오피스 시장은 거시경제환경의 변화에 보다 민감한 시장으로 향후 이자율과 경제성장 등에 영향을 미칠 수 있는 통화정책 등의 변화를 주요한 투자기준으로 고려해야 할 필요성이 높다고 할 수 있다.