• Composites Research
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• 제34권3호
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• pp.167-173
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• 2021

최근 금속-복합재료 하이브리드 구조는 설계 유연성과 우수한 기계적 특성 때문에 자동차나 항공기 등 다양한 분야에 응용이 가능한 매우 매력적인 소재 시스템이 되었다. 한편, 버려지는 재료를 줄이고 환경 오염을 막기 위한 재활용이 아주 중요해졌다. 많은 국가에서 자동차나 전자제품의 재활용 규정을 만들어 적용하고 있으나, 금속-복합재료 하이브리드 구조는 아직 연구개발 및 응용의 초기 단계로 재활용에 대해서는 충분히 고려되지 않고 있다. 본 연구에서는 재활용 업체에서 도입할 수 있는 금속-복합재료 하이브리드 구조의 재활용 프로세스를 개발하고 최적화하였다.

• Structural Monitoring and Maintenance
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• 제9권2호
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• pp.179-200
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• 2022

This paper proposes a data-driven methodology for online early damage identification under changing environmental conditions. The proposed method relies on two data analysis methods: feature-based method and hybrid principal component analysis (PCA) and kernel PCA to separate damage from environmental influences. First, spectral sub-band features, namely, spectral sub-band centroids (SSCs) and log spectral sub-band energies (LSSEs), are proposed as damage-sensitive features to extract damage information from measured structural responses. Second, hybrid modeling by integrating PCA and kernel PCA is performed on the spectral sub-band feature matrix for data normalization to extract both linear and nonlinear features for nonlinear procedure monitoring. After feature normalization, suppressing environmental effects, the control charts (Hotelling T² and SPE statistics) is implemented to novelty detection and distinguish damage in structures. The hybrid PCA-KPCA technique is compared to KPCA by applying support vector machine (SVM) to evaluate the effectiveness of its performance in detecting damage. The proposed method is verified through numerical and full-scale studies (a Bridge Health Monitoring (BHM) Benchmark Problem and a cable-stayed bridge in China). The results demonstrate that the proposed method can detect the structural damage accurately and reduce false alarms by suppressing the effects and interference of environmental variations.

• 한국자동차공학회논문집
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• 제20권3호
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• pp.52-57
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• 2012

Proper door effort is required for the safety of passenger and pedestrian while securing door operating convenience. 3D finite element analyses for a hybrid door checker were carried out to estimate door checker arm resistance force. And, from the estimated door checker arm resistance force and theoretically calculated self-closing force, door effort was predicted. The analysis results at checker arm peaks showed excellent correlation with the test results. Also, in order to reduce solving time, a modified model with simple spring element was investigated. Finally an equation to easily calculate checker arm resistance force from checker arm shape and spring constant was suggested and its usefulness in early design stage was discussed.

• 한국작물학회지
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• 제44권4호
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• pp.391-395
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• 1999

Barnyardgrass had relatively higher growth vigor at the earlier growth stage than inbred rice did, showing the 2 fold higher $\alpha$-amylase activity during the periods of germination and large leaf area Expansion with high net photosynthetic rate at the earlier autotrophic stage, but it performed weak growth at the late growth stage. However, the hlybrid rice Shanyou 63 had significantly higher $\alpha$-amylase activity and net photosynthetic rate than that of barnyardgrass, exhibiting heterosis for two physiologica1 traits during the germination (6~12 days) and autotrophic phase, respectively. Accordingly, hybrid rice, Shanyou 63, exhibited heterotic effect at the early growing stage when were presented with barnyardgrass. Shanyou 63 exhibited stronger tillering ability, faster leaf area expansion and higher net photosynthetic rate than those of barnyardgrass.

• 경영과학
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• 제30권2호
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• pp.31-42
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• 2013

The vehicle routing problem (VRP) can be described as a problem to find the optimum traveling routes from one or several depot (s) to number of geographically scattered customers. This study executes a revised Heterogeneous Vehicle Routing Problem (HVRP) to minimize the cost that needs to conduct efficiently the snow removal operations of Air Wing under available resources and limited operations time. For this HVRP, we model the algorithm of an hybrid Ant Colony System (ACS). In the initial step for finding a solution, the modeled algorithm applies various alterations of a parameter that presents an amount of pheromone coming out from ants. This improvement of the initial solution illustrates to affect to derive better result ultimately. The purpose of this study proves that the algorithm using Hybrid heuristic incorporated in tabu and ACS develops the early studies to search best solution.

• 전기학회논문지
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• 제57권8호
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• pp.1334-1341
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• 2008

This paper introduces an approach of Hybrid Particle Swarm Optimization(HPSO) for a security-constrained economic dispatch(SCED) with line flow constraints. To reduce a early convergence effect of PSO algorithm, we proposed HPSO algorithm considering a mutation characteristic of Genetic Algorithm(GA). In power system, for considering N-1 line contingency, we have chosen critical line contingency through a process of Screening and Selection based on PI(performance Index). To prove the ability of the proposed HPSO in solving nonlinear optimization problems, SCED problems with nonconvex solution spaces are considered and solved with three different approach(Conventional GA, PSO, HPSO). We have applied to IEEE 118 bus system for verifying a usefulness of the proposed algorithm.

• Journal of Chest Surgery
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• 제32권12호
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• pp.1127-1130
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• 1999

Percutaneous coronary intervention including intracoronary stenting is currently an accepted treatment modality in the treatment of coronary artery disease and is widely performed to treat the patient with multivessel disease with decreased morbidities and less cost compared with conventional coronary rtery bypass grafting(CABG), Repeated interventions due to restenosis even after successful angioplasty are the major disadvantage of the angioplsty especially when the lesion is located inthe left anterior descending artery(LAD) Recently CABG through left anterior small thoracotomy using the left internal thoracic artery to revascularize the LAD territory without cardiopulmonary bypass so called Minimally Invasive Direct Coronary Artery Bypass(MIDCAB) was intrduced and performed with comparable early outcomes. In this regard the integrated approach with percutaneous coronary intervention and minimally invasive direct coronary artery bypass surgery so called 'Hybrid CABG' was suggested to be an effective treatment in suitable patients with multivessel coronary artery disease. We report three cases of Hybrid CABG.

• The Plant Pathology Journal
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• 제19권5호
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• pp.253-256
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• 2003

Citrus canker disease is caused by bacteria Xanthomonas axonopodis .pv. Citri. Shiranuhi cultivar, a hybrid of Kiyomi tangor and Nakano No.3 ponkan was evaluated for resistance to citrus canker based on initiation of disease, percent area of lesion infected and growth rate of bacteria in the leaf under growth chamber condition. Significant differences between susceptible plant and resistant plants were observed in these assays. Resistant plants showed delayed disease symptoms compared to the susceptible plants after spray inoculation of the pathogen. The resistant verities, satsuma, yuzu, and Shiranuhi showed symptoms after six days where as susceptible, mexican lime showed the symptoms just after three days of inoculation. 18 days after inoculation, percent area of lesions developed on leaf and disease severity differed significantly in susceptible and resistant plants, and were ranked as follows: mexican lime > early satsuma =Shiranuhi =yuzu (P <, 0.01). However, 30 days after inoculation, percent area of lesion was further differentiated into resistant and highly resistant plants. That was ranked as follows: sweet orange> early satsuma =Shiranuhi =Kiyomi > yuzu (P < 0.01). These results indicate that host reaction to the bacterial was more distinct when the disease developed for a longer period. Growth rates of a citrus canker bacterium during 16 40 h also were distinct after infiltration into leaves of susceptible and resistant plants, and were ranked as follows: sweet orange> early satsuma =Shiranuhi =Kiyomi =yuzu (P < 0.01). Based on these results, we concluded that Shiranuhi is resistant to citrus canker as compared to Kiyomi, early satsuma, and yuzu.

• Molecules and Cells
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• 제19권1호
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• pp.39-45
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• 2005

RPK118 is a sphingosine kinase-1-binding protein that has been implicated in sphingosine 1 phosphate-mediated signaling. It contains a PX (phox homology) domain and two pseudo-kinase domains, and co-localizes with sphingosine kinase-1 on early endosomes. In this study we identified a novel RPK118-binding protein, PRDX3 (peroxiredoxin-3), by yeast two-hybrid screening. The interaction between these proteins was confirmed by pull-down assays and co-immunoprecipitation experiments. Deletion studies showed that RPK118 interacted with PRDX3 through its pseudokinase domains, and with early endosomes through its PX domain. Double immunofluorescence experiments demonstrated that PRDX3 co-localized with RPK118 on early endosomes in COS7 cells. PRDX3 is a member of the antioxidant family of proteins synthesized in the cytoplasm and functioning in mitochondria. Our findings indicate that RPK118 is a PRDX3-binding protein that may be involved in transporting PRDX3 from the cytoplasm to its mitochondrial site of function or to other membrane structures via endosome trafficking.

• 한국멀티미디어학회논문지
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• 제9권7호
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• pp.854-863
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• 2006

휴대 모바일 멀티미디어 통신 서비스인 휴대인터넷 사업자가 선정되어, 곧 상용 서비스가 시작된다. 멀티미디어 서비스를 제공하기 위하여 효율적인 멀티캐스트 기법 사용이 불가피한 상황이지만 기술적 혹은 경제적인 이유로 상용서비스 초기단계에 통신망 전체를 IP 멀티캐스트로 구축하는 것은 쉽지 않으며 응용계층 멀티캐스트 방식 및 복합 멀티캐스트 방식도 고려하여야 한다. 본 논문에서는 휴대인터넷 사업자중 한 사업자의 휴대인터넷망 모델링을 통하여 복합 멀티캐스트 방식을 제안하였고, 대표적인 IP 멀티캐스트 성능에 대하여 어느 정도 성능저하가 있는가를 평가하였다. 성능평가를 위하여 시뮬레이션망에서 복합방식 멀티캐스트를 모델링하는 시뮬레이션 방안을 제시하였다. 성능평가결과 휴대인터넷 서비스망에서 단말의 수가 충분히 많으면, 복합방식 멀티캐스트의 성능이 IP 멀티캐스트에 비하여 큰 차이가 없음을 보였다.