• 한국수산과학회지
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• 제36권4호
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• pp.389-401
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• 2003

The changes in structure and abundance of taxon or species groups in the East Sea ecosystem were compared between pre- and post-Climatic Regime Shift (CRS) occurred in the mid 1970s using an ECOPATH model. Although the East Sea ecosystem consisted of primary producers, primary consumers, secondary consumers and terminal consumers most species groups were classified as secondary consumers. The mean trophic level between pre- and post-CRS increased from 3.09 during the pre-CRS period to 3.28 during the post-CRS period. Total biomass of the species groups in the East Sea ecosystem increased by $9\%$ due to the CRS, and total catch increased by $48\%.$ The most significant differences between pre- and post-CRS models occurred at the mid/high trophic levels occupied by fishes and cephalopods. Relative contribution of the different species groups to the total energy flow was calculated for the trophic level III. As a result, the status by the dominant species in the East Sea ecosystem shifted from cephalopods to walleye pollock due to the CRS. Relative contribution of 5 species, which were commercially important, such as Pacific saury, Pacific sardine, filefish, walleye pollock and sandfish in trophic level III, were also changed due to the CRS. Finally, the CRS turned out to cause large variations in biomass and catch of fisheries resources as well as the status and role of the major species.

• 한국물환경학회지
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• 제39권4호
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• pp.302-315
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• 2023

Distribution characteristics and altitudinal gradient of four species (E. strigata, E. separigata, E. orientalis-sachalinensis group) of the mayfly genus Ephemera (Order Ephemeroptera) were analyzed with probability distribution models (exponential, normal, lognormal, logistic, Weibull, gamma, beta, Gumbel). Data was collected from 23,846 sampling units of 6,787 sites in Korea from 2010 to 2021. The beta distribution model showed the best fit for positively skewed E. orientalis-sachalinensis and little-skewed E. strigata along with altitudinal gradient. The reversed lognormal distribution model showed the best-fit for negatively skewed E. separigata. E. orientalis-sachalinensis distributed at the range of altitude 1~700 m (mean 251 m, median 226 m, mode 124 m, and standard deviation 161 m), E. strigata distributed at the range of altitude 5~871 m (mean 474 m, median 478 m, mode 492 m, and standard deviation 200 m), E. separigata distributed at the range of altitude 7~846 m (mean 620 m, median 659 m, mode 760 m, and standard deviation 181 m). Altitudinal habitat suitability ranges were estimated to be 42~257 m for E. orientalis-sachalinensis, 335~644 m for E. strigata, and 641~824 m for E. separigata. Based on the altitudinal spectrum of suitability and altitude-related temperature analysis results, E. orientalis-sachalinensis was estimated to be thermophilic, E. strigata to be mesophilic, and E. separigata to be thermophobic. This is the first national-scale evaluation of the altitudinal distribution of Ephemera in Korea. These results will be used in a further research study on altitudinal shift of the species of Ephemera under climate change.

• 농업과학연구
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• 제38권2호
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• pp.219-225
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• 2011

Changes in biota, species distribution range shift and catastrophic climate influence due to recent global warming have been observed during the last century. Since global warming affects various sectors, such as agriculture and vegetation, it is important to predict more accurate impact of future climate change. The purpose of this study is to examine the observed distribution of Abeliophyllum distichum in the Korean peninsula. For this purpose, two period (present and future) climate data were used. Mean data between 1950 and 2000, were used as the present value and the year 2050 and 2080 data from A1B senario in IPCC SRES were used for the future value. Potential habitation is analyzed by MaxEnt(Maximum Entropy model), and Abeliophyllum distichum's coordinates data were used as a dependent variable and independent variables are composed of environmental data such as BioClim, altitude, aspect and slope. The result of six types GCM mean calculation, the potential habitability decreased by 40-60% of the average existing distribution. The methodogies and results of this research can be applicable to the climate changing adaptation stratiegies for the biodiversity conservation.

• Safety and Health at Work
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• 제6권4호
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• pp.305-311
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• 2015

Background: The purpose of this study was to examine the relationship nursing personal and workplace system factors (work disability) and work ability index scores in Ontario, Canada. Methods: A total of 111 registered nurses were randomly selected from the total number of registered nurses on staff in the labor, delivery, recovery, and postpartum areas of four northeastern Ontario hospitals. Using a stratified random design approach, 51 participants were randomly selected in four northeastern Ontario cities. Results: A total of 51 (45.9% response rate) online questionnaires were returned and another 60 (54.1% response rate) were completed using the paper format. The obstetric workforce in northeastern Ontario was predominately female (94.6%) with a mean age of 41.9 (standard deviation = 10.2). In the personal systems model, three variables: marital status (p = 0.025), respondent ethnicity (p = 0.026), and mean number of patients per shift (p = 0.049) were significantly contributed to the variance in work ability scores. In the workplace system model, job and career satisfaction (p = 0.026) had a positive influence on work ability scores, while work absenteeism (p = 0.023) demonstrated an inverse relationship with work ability scores. In the combined model, all the predictors were significantly related to work ability scores. Conclusion: Work ability is closely related to job and career satisfaction, and perceived control at work among obstetric nursing. In order to improve work ability, nurses need to work in environments that support them and allow them to be engaged in the decision-making processes.

• 정보처리학회논문지:소프트웨어 및 데이터공학
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• 제1권3호
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• pp.177-186
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• 2012

본 논문에서는 실시간 손동작 분석을 위한 깊이정보 기반 손 영역 검출 및 추적 방법을 제안한다. 이를 위해 손 영역 검출단계에서는 깊이정보만을 이용하여 손 영역의 특징인 형태모델을 생성하고, 검출 시 움직임 정보와 영역 확장(Region Growing)을 통해 객체를 추출한다. 추출된 객체는 사전에 생성된 형태모델과 크기정보를 분석하여 최종 손 영역으로 판정한다. 판정된 손 객체는 추적단계에서 중심점 전이 과정을 통해 이전 중심점과의 최근접점을 획득하고, 최근접점으로부터 영역 확장과 깊이기반 적응적 평균 이동 기법(DAM-Shift)을 통해 새로운 중심점을 검출하여 추적한다. 마지막으로 성능 검증을 위해 다양한 손 모양과 속도 및 위치에 대한 다양한 환경에서 실험하고, 검출속도와 추적된 궤적의 정량적, 정성적 분석을 통해 제안하는 방법의 효율성을 입증한다.

• 한국정보전자통신기술학회논문지
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• 제2권1호
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• pp.23-28
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• 2009

히스토그램에 의한 객체 유형 인식 방법은 최근 들어 많은 연구가 이루어지고 있다. 그러나 대부분의 히스토그램 기반의 객체 추적이 칼라 모델을 사용하여 견실성을 개선하였지만 아직 충분히 견실하다고 할 수 없다. 이러한 단점을 보안하기 위하여 본 논문에서는 연속적인 프레임에서 히스토그램을 이용하여 객체를 표현하고 추적하는 방법을 제시하고자 한다. 자동차를 대상으로 실험한 결과 80m 거리 이내에서 신뢰성 있는 방법임을 확인하였다.

• 한국통신학회논문지
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• 제34권3C호
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• pp.274-278
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• 2009

히스토그램에 의한 객체 유형 인식 방법은 최근 들어 많은 연구가 이루어지고 있다. 그러나 대부분의 히스토그램 기반의 객체 추적이 칼라 모델을 사용하여 견실성을 개선하였지만 아직 충분히 견실하다고 할 수 없다. 이러한 단점을 보안하기 위하여 본 논문에서는 연속적인 프레임에서 히스토그램을 이용하여 객체를 표현하고 추적하는 방법을 제시하고자 한다. 자동차를 대상으로 실험한 결과 80m 거리 이내에서 신뢰성 있는 방법임을 확인하였다.

• Journal of the Korean Statistical Society
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• 제36권4호
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• pp.457-469
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• 2007

Many procedures are available to identify a single outlier or an isolated influential point in linear regression and logistic regression. But the detection of influential points or multiple outliers is more difficult, owing to masking and swamping problems. The multiple outlier detection methods for logistic regression have not been studied from the points of direct procedure yet. In this paper we consider the direct methods for logistic regression by extending the $Pe\tilde{n}a$ and Yohai (1995) influence matrix algorithm. We define the influence matrix in logistic regression by using Cook's distance in logistic regression, and test multiple outliers by using the mean shift model. To show accuracy of the proposed multiple outlier detection algorithm, we simulate artificial data including multiple outliers with masking and swamping.

• Journal of Ubiquitous Convergence Technology
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• 제1권1호
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• pp.3-8
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• 2007

This paper presents a set of techniques used in a real-time visual surveillance system. The system is implemented on a low-cost embedded DSP platform that is designed to work with stationary video sources. It consists of detection, a tracking and a classification module. The detector uses a statistical method to establish the background model and extract the foreground pixels. These pixels are grouped into blobs which are classified into single person, people in a group and other objects by the dynamic periodicity analysis. The tracking module uses mean shift algorithm to locate the target position. The system aims to control the human density in the surveilled scene and detect what happens abnormally. The major advantage of this system is the real-time capability and it only requires a video stream without other additional sensors. We evaluate the system in the real application, for example monitoring the subway entrance and the building hall, and the results prove the system's superior performance.

• Applied Biological Chemistry
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• 제46권4호
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• pp.305-310
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• 2003

Hydrophobic core가 변이된 유비퀴틴 단백질이 pH 2 용액에서 보이는 구조적인 특성을 여러 분광학적 방법으로 측정하였다. 낮은 pH값을 갖는 용액에서 이 변이 유비퀴틴의 intrinsic tryptophan fluorescence emission spectrum은 unfolded 상태보다 약간 blue shift되어 있고 또한 그 intensity도 상당히 낮게 나타났다. 이는 이 용액 조건에서 이 변이 유비퀴틴의 삼차구조가 약간 남아 있는 것을 의미한다. 같은 용액에서 이 변이 유비쥐틴의 far-UV circular dichroic spectrum은 native 상태나 unfolded 상태의 spectrum과 현저히 달랐으며 220 nm 에서의 molar ellipticity 값을 통하여 볼 때 pH 2인 용액에서 상당량의 이차구조를 지니고 있었다. 또한 같은 용액에서 이 변이 유비퀴틴은 hydrophobic dye인 8-anilinonaphthalene-1-sulfonic acid(ANS)외 fluorescence emission intensity를 증가시키고 fluorescence emission maximum이 짧은 파장에서 나타나게 하였다(blue shift). 이러한 현상은 pH 2 용액에서 이 변이 유비퀴틴의 hydrophobic core가 느슨하여져서 hydrophobic dye인 ANS가 결합할 수 있는 구조를 띠고 있음을 나타낸다. 이러한 분광학적인 관찰은 이 변이 유비귀틴이 pH 2인 용액에서 상당량의 이차구조를 지니고 있지만 hydrophobic core는 느슨하게 형성된 molten globule과 같은 형태를 지니고 있음을 나타낸다. 이 변이 유비퀴틴의 molten 히obule 형태는 단백질 폴딩 반응의 경로를 연구할 수 있는 좋은 모델이 될 수 있을 것으로 생각된다.