• 한국기계가공학회지
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• 제17권6호
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• pp.98-104
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• 2018

Deflected 4-way panels of ceiling air conditioners produced by injection molding process have caused dew condensation at the edge of products. In order to prevent this drawback with reducing weight and deformation, this study proposed renovated process adopting microcellular foaming. According to results from 2-sample t-test and analysis of variance(ANOVA), the critical factors affecting weight were melt temperature and injection speed. In addition, the vital effects on deformation were structure at the edge, mold temperature and cooling time. Optimal conditions of these parameters were derived by regressive analysis with CAE and response surface method(RSM), and then applied to an actual design and process stage to analyze performance. As a results, it clearly showed that new process improved process capability as well as reduced both weight and deformation by 18.8% and 71.9% respectively compared to the conventional method.

• Parasites, Hosts and Diseases
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• 제54권3호
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• pp.363-368
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• 2016

We describe here the mass death of predatory carp, Chanodichthys erythropterus, in Korea induced by plerocercoid larvae of Ligula intestinalis as a result of host manipulation. The carcasses of fish with ligulid larvae were first found in the river-edge areas of Chilgok-bo in Nakdong-gang (River), Korea at early February 2016. This ecological phenomena also occurred in the adjacent areas of 3 dams of Nakdong-gang, i.e., Gangjeong-bo, Dalseong-bo, and Hapcheon-Changnyeong-bo. Total 1,173 fish carcasses were collected from the 4 regions. To examine the cause of death, we captured 10 wondering carp in the river-edge areas of Hapcheon-Changnyeong-bo with a landing net. They were 24.0-28.5 cm in length and 147-257 g in weight, and had 2-11 plerocercoid larvae in the abdominal cavity. Their digestive organs were slender and empty, and reproductive organs were not observed at all. The plerocercoid larvae occupied almost all spaces of the abdominal cavity under the air bladders. The proportion of larvae per fish was 14.6-32.1% of body weight. The larvae were ivory-white, 21.5-63.0 cm long, and 6.0-13.8 g in weight. We suggest that the preference for the river-edge in infected fish during winter is a modified behavioral response by host manipulation of the tapeworm larvae. The life cycle of this tapeworm seems to be successfully continued as the infected fish can be easily eaten by avian definitive hosts.

• 한국정보과학회논문지:정보통신
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• 제31권2호
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• pp.123-130
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• 2004

경로 설정 및 파장 할당(Routing and Wavelength Assignment) 문제는 파장 할당 전송 기법(Wavelength Division Multiplexing)을 기반으로 하는 광 네트워크에서 중요한 분야이다. 경로 설정 및 파장 할당 문제는 선형 프로그램(Linear Programming)과 그래프 컬러링(Graph Coloring)의 조합으로 해결되거나, 경로 선택에 기반 한 그래프 알고리즘에 의해서 해결된다. 이와 같은 방법은 복잡하며 휴리스틱 알고리즘(heuristic algorithm)이 요구된다. 본 논문에서는 각각의 연결 요구에 대한 최대한의 EDPs(Edge Disjoint Paths)를 구함으로써 경로 설정 및 파장 할당 문제를 효율적으로 해결하는 새로운 방법을 제안한다. 이렇게 구한 EDPs는 참조 테이블에 저장되고 가중치 매트릭스의 갱신에 사용된다. 각 연결 요구에 대한 경로는 순서대로 가중치 매트릭스를 참조하여 결정한다. 본 논문에서 제안하는 알고리즘이 현재 실질적으로 효율적이라 알려진 BGA for EDP(Bounded Greedy Approach for EDP)보다 약 50%의 수행 시간 내에 같거나 작은 파장 수를 사용하여 연결 요구를 만족시켜주고 있음을 시뮬레이션을 통해서 확인할 수 있다.

• 대한간호학회지
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• 제47권6호
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• pp.806-816
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• 2017

Purpose: As comprehensive nursing care service has gradually expanded, it has become necessary to explore the various opinions about it. The purpose of this study is to explore the large amount of text data regarding comprehensive nursing care service extracted from online news and social media by applying a semantic network analysis. Methods: The web pages of the Korean Nurses Association (KNA) News, major daily newspapers, and Twitter were crawled by searching the keyword 'comprehensive nursing care service' using Python. A morphological analysis was performed using KoNLPy. Nodes on a 'comprehensive nursing care service' cluster were selected, and frequency, edge weight, and degree centrality were calculated and visualized with Gephi for the semantic network. Results: A total of 536 news pages and 464 tweets were analyzed. In the KNA News and major daily newspapers, 'nursing workforce' and 'nursing service' were highly rated in frequency, edge weight, and degree centrality. On Twitter, the most frequent nodes were 'National Health Insurance Service' and 'comprehensive nursing care service hospital.' The nodes with the highest edge weight were 'national health insurance,' 'wards without caregiver presence,' and 'caregiving costs.' 'National Health Insurance Service' was highest in degree centrality. Conclusion: This study provides an example of how to use atypical big data for a nursing issue through semantic network analysis to explore diverse perspectives surrounding the nursing community through various media sources. Applying semantic network analysis to online big data to gather information regarding various nursing issues would help to explore opinions for formulating and implementing nursing policies.

• 정보처리학회논문지B
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• 제9B권5호
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• pp.673-680
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• 2002

이 논문은 진화 프로그래밍과 개선된 역전파 알고리즘을 이용한 에지 검출 방법을 제안한다. 진화 프로그래밍은 알고리즘의 성능저하와 계산비용을 고려하여 교차 연산은 수행하지 않고, 선택연산자와 돌연변이 연산자를 사용한다. 개선된 역전파 알고리즘은 학습단계에서 연결강도를 변화시킬 때 이전학습단계의 연결강도를 보조적으로 활용하는 방법이다. 이 개선된 역전파 알고리즘은 학습률 $\alpha$를 작은값으로 설정하기 때문에 각 학습단계에서의 연결강도 변화량이 기존의 방법에 비해 상대적으로 줄어들게 되어 학습이 느려지는 문제점을 해결하였다. 실험결과 학습시간과 검출률에 있어서 GA-BP(GA : Genetic Algorithm BP : Back-Propagation)를 이용한 방법보다 제안한 EP-MBP(EP : Evolutionary Programming, MBP :Momentum Back-Propagation)를 이용하여 학습시킨 방법이 학습시간의 단축과 효율적인 에지 검출 결과를 얻을 수 있었다.

• 한국전산구조공학회논문집
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• 제30권5호
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• pp.445-452
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• 2017

본 연구에서의 날개 앞전은 날개의 공기역학적인 기능뿐만 아니라 조류 등의 외부의 손상을 줄 수 있는 것으로부터 날개 내부 구성요소를 보호하고 안전한 항공기 운항을 위한 반드시 필요한 구조 요소이다. 복합재 무인기의 날개 경량화를 위한 최적의 제작 모델을 비교 검토하였다. MSC. Patran/Nastran을 이용한 유한요소해석을 통하여 비틀림 하중의 변위 형상을 비교 확인하였으며, 각 모델들의 비틀림 강도 실험을 통하여 적층 유형, 두께 변화 및 형상 적용에 따른 경량화 성능 개선을 확인하므로써 소형 복합재 무인기 최적의 경량화 날개 앞전스킨의 형태를 제시하였다.

• 융합신호처리학회논문지
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• 제17권2호
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• pp.71-76
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• 2016

디지털 영상처리는 의료산업, 위성사진, 공장자동화 영상인식 등 넓고 다양한 분양에 활용되고 있다. 하지만 이러한 영상 데이터는 처리, 전송, 저장하는 과정에서 여러 외부 원인에 의해 열화가 발생한다. 영상에 첨가되는 잡음에는 AWGN, salt and pepper 잡음이 대표적이다. AWGN에 훼손된 영상을 복원하기 위한 공간영역 방법에는 MF, CWMF, AWMF 등이 있으며, 기존의 방법들은 에지와 같은 상세 정보를 훼손하는 특성이 있다. 따라서 본 논문에서는 AWGN 환경에서 국부 마스크의 에지 크기에 따라 화소 방향에 따른 가중치 필터, 공간 가중치 필터 및 평균 필터의 가중치를 다르게 적용하는 알고리즘을 제안하였다. 그리고 제안한 알고리즘의 우수성을 입증하기 위해, PSNR을 사용하여 기존의 방법들과 그 성능을 비교하였다.

• 대한전기학회논문지:시스템및제어부문D
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• 제51권8호
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• pp.335-343
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• 2002

A segment matching algorithm in stereo vision via the fusion of multiple features on long edge segments is proposed. One problem of the previous segment matching algorithm is the similarity among the segments caused from its short length. In the proposed algorithm, edges are composed of longer segments which are obtained by breaking the edges only at the locations with distinguished changes of the shape. Such long segments can contain extra features such as curvature ratio and length of segments which could not be included in shorter ones. Use of such additional features enhances the matching accuracy significantly To fuse multiple features for matching, weighting value determination algorithm which is computed according to the degree of the contribution of each factor is proposed. The stereo matching simulations with the proposed algorithm are done about various images and their results are included.

• Journal of Information Processing Systems
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• 제15권1호
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• pp.7-21
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• 2019

In order to improve the edge segmentation effect of the level set image segmentation and avoid the influence of the initial contour on the level set method, a saliency level set image segmentation model based on local Renyi entropy is proposed. Firstly, the saliency map of the original image is extracted by using saliency detection algorithm. And the outline of the saliency map can be used to initialize the level set. Secondly, the local energy and edge energy of the image are obtained by using local Renyi entropy and Canny operator respectively. At the same time, new adaptive weight coefficient and boundary indication function are constructed. Finally, the local binary fitting energy model (LBF) as an external energy term is introduced. In this paper, the contrast experiments are implemented in different image database. The robustness of the proposed model for segmentation of images with intensity inhomogeneity and complicated edges is verified.

• Journal of information and communication convergence engineering
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• 제20권3호
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• pp.195-203
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• 2022

Noise generated during image acquisition and transmission can negatively impact the results of image processing applications, and noise removal is typically a part of image preprocessing. Denoising techniques combined with nonlocal techniques have received significant attention in recent years, owing to the development of sophisticated hardware and image processing algorithms, much attention has been paid to; however, this approach is relatively poor for edge preservation of fine image details. To address this limitation, the current study combined a steering kernel technique with adaptive masks that can adjust the size according to the noise intensity of an image. The algorithm sets the steering weight based on a similarity comparison, allowing it to respond to edge components more effectively. The proposed algorithm was compared with existing denoising algorithms using quantitative evaluation and enlarged images. The proposed algorithm exhibited good general denoising performance and better performance in edge area processing than existing non-local techniques.