• Journal of applied mathematics & informatics
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• v.24 no.1_2
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• pp.333-342
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• 2007

A nonsmooth PGD scheme for minimizing a nonsmooth convex function is presented. In the parallelization step of the algorithm, a method due to Pang, Han and Pangaraj (1991), [7], is employed to solve a subproblem for constructing search directions. The convergence analysis is given as well.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.49 no.3
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• pp.233-241
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• 2021

As increasing the feasibility of the eVTOL UAM(electric vertical take-off and landing urban air mobility), numerous corporations and laboratories are conducting researches. In the aircraft development process, estimating the cost of the aircraft is essential part in terms of budgeting and commercial viability analysis. However, it is difficult to predict the cost of an eVTOL UAM owing to various configurations and little open cost information. This paper presents a novel method to predict the vehicle cost of various eVTOL configurations by modifying previous studies of the aircraft cost estimation. A vehicle cost of Wisk Cora is calculated by the presented method as an example to illuminate the method. The method is indirectly validated by comparing the vehicle costs of six representative eVTOL aircraft with those from the UAM study reports.

• Animal cells and systems
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• v.13 no.2
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• pp.141-145
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• 2009

Two new species of the family Spongiidae, Spongia (Heterofibria) cora/lina n. sp. and Spongia (Heterofibria) purpurea n. sp. are described. They were collected from Gageodo Island, Jeollanam-do, Korea. Spongia (H.) coral/ina n. sp. is closest to S. (H.) cristata Cook & Bergquist (2001) from New Zealand in skeletal features, but the new species differs from S. (H.) cristata by the arrangement of fibres and growth form. Spongia (H.) purpurea n. sp. closley resembles S. (H.) cristata, but the new species differs from New Zealand specimens by the arragement and thickness of pseudo-tertiary fibres.

• Journal of applied mathematics & informatics
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• v.22 no.1_2
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• pp.193-208
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• 2006

A modified BFGS algorithm for solving the unconstrained optimization, whose Hessian matrix at the minimum point of the convex function is of rank defects, is presented in this paper. The main idea of the algorithm is first to add a modified term to the convex function for obtain an equivalent model, then simply the model to get the modified BFGS algorithm. The superlinear convergence property of the algorithm is proved in this paper. To compared with the Tensor algorithms presented by R. B. Schnabel (seing [4],[5]), this method is more efficient for solving singular unconstrained optimization in computing amount and complication.

• Journal of Nutrition and Health
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• v.20 no.1
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• pp.15-24
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• 1987

To study effects of heated oil on lipid peroxidation in rat liver, rats were fed 3 and 6 weeks by intubating oils heated for l1(HA group) and 24 hours (HB group) at 18$0^{\circ}C$. The contents of lipid peroxides and vitamin E, and the activities of super oxide dismutase and glutathione peroxidase in liver were measured. Histological changes of the liver tissue were observed. In both HA and HE groups, the contents of lipid peroxides and the activities of superoxide dismutase were increased, but the activities of glutathione peroxidase and the contents of vitamin E in liver were decreased when compared to the control group which was fed fresh cora oils. During the oil feeding period, the activities of superoxide dismutase and the contents of vitamin E were not significantly changed, but the activities of glutathione peroxidase were decreased, and lipid peroxides were increased in the 3 weeks than in 6 weeks. In HB liver, the heterochromatin of nucleus increased, mitochondria swellen, cristae in mitochondria disappeared, fat droplet and secondary lysosome increased and lumen of rough endoplasmic reticulum enlarged, compared with that of the control group. These phenomena in HA group were less pronounced.

• Journal of Global Scholars of Marketing Science
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• v.17 no.2
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• pp.99-110
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• 2007

The widespread use of self-service concepts in retailing has resulted in increased attention to the design of retail environments and to stimuli operating at the point of sale. One such merchandising technique, the "bundled presentation", i.e., related products are presented in close proximity to each other, is widely used by retailers but has rarely been investigated by academic consumer researchers. This study presents the results of a field experiment into the effects of presenting products in their usage context. Customers' attitudes towards the same product displayed in different ways are compared with each other. The results show that related products, i.e., products that are used together, should be presented in a coordinated display. Furthermore, the bundled presentation enhanced consumers' attitudes of the product when they saw it first in a bundled presentation and then evaluated it in front of a traditional presentation.

• Proceedings of the Korea Information Processing Society Conference
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• 2024.05a
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• pp.524-526
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• 2024

컴퓨터 과학(CS) 분야는 다른 학문 분야에 비해 연구 동향이 빠르게 변하는 특성을 가지고 있다. 그래프 마이닝에서 활발히 사용되는 CS 분야 논문 데이터셋를(e.g., Cora, Citeseer, DBLP)은 오래된 논문을 중심으로 구성되어 있어 이러한 특성을 제대로 반영하지 못하는 한계가 있다. 따라서 본논문에서는 CS 분야의 최신 트렌드를 반영하는 논문 데이터셋을 제안한다. 이를 위해, 우리는 CS 분야 논문을 활발히 공개하는 플랫폼인 arXiv 에서 2007 년부터 2023 년까지 해당 플랫폼에서 공개된 논문들을 수집하고, 이를 기반으로 공저자 그래프 및 인용 그래프로 구축한다. 해당 데이터셋을 대상으로 폭넓은 분석을 통해, 우리가 구축한 데이터셋이 실세계 그래프 네트워크 특성을 잘 반영하고 있음을 보인다. 또한, 향휴에 해당 데이터셋을 사용하려는 연구자들을 위해, 해당 데이터셋에서의 기존 그래프 기반 응용들의 노드 분류 성능을 제시한다.

• Nuclear Engineering and Technology
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• v.51 no.8
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• pp.1916-1938
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• 2019

The objective of this paper is to discuss the modeling principles of phenomena governing core degradation/melting and in-vessel melt relocation during severe accidents in light water reactors. The proposed modeling approach has been applied in the development of a new accident simulation package, COMPASS (COre Meltdown Progression Accident Simulation Software). COMPASS can be used either as a stand-alone tool to simulate in-vessel meltdown progression up to and including RPV failure, or as a component of an integrated simulation package being developed in Korea for the APR1400 reactor. Interestingly, since the emphasis in the development of COMPASS modeling framework has been on capturing generic mechanistic aspects of accident progression in light water reactors, several parts of the overall model should be useful for future accident studies of other reactor designs, both PWRs and BWRs. The issues discussed in the paper include the overall structure of the model, the rationale behind the formulation of the governing equations and the associated simplifying assumptions, as well as the methodology used to verify both the physical and numerical consistencies of the overall solver. Furthermore, the results of COMPASS validation against two experimental data sets (CORA and PHEBUS) are shown, as well as of the predicted accident progression at TMI-2 reactor.

• Journal of Astronomy and Space Sciences
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• v.33 no.4
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• pp.305-311
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• 2016

The spatial size and variation of Arctic sea ice play an important role in Earth's climate system. These are affected by conditions in the polar atmosphere and Arctic sea temperatures. The Arctic sea ice concentration is calculated from brightness temperature data derived from the Defense Meteorological Satellite program (DMSP) F13 Special Sensor Microwave/Imagers (SSMI) and the DMSP F17 Special Sensor Microwave Imager/Sounder (SSMIS) sensors. Many previous studies point to significant reductions in sea ice and their causes. We investigated the variability of Arctic sea ice using the daily sea ice concentration data from passive microwave observations to identify the sea ice melting regions near the Arctic polar ice cap. We discovered the abnormal melting of the Arctic sea ice near the North Pole during the summer and the winter. This phenomenon is hard to explain only surface air temperature or solar heating as suggested by recent studies. We propose a hypothesis explaining this phenomenon. The heat from the deep sea in Arctic Ocean ridges and/or the hydrothermal vents might be contributing to the melting of Arctic sea ice. This hypothesis could be verified by the observation of warm water column structure below the melting or thinning arctic sea ice through the project such as Coriolis dataset for reanalysis (CORA).

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.21
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• pp.9191-9197
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• 2014

The aims of this study were to assess whether Indonesian women with breast cancer havea higher external health locus of control (HLC) than healthy women, and to explore the association between HLC and symptoms of anxiety and depression. In this study, 120 consecutive women with breast cancer were recruited at the outpatient surgical oncology clinic at the Hasan Sadikin Hospital in Bandung. One hundred and twenty two healthy women were recruited from the Bandung area as controls. A standard demographic form, Form C of the Multidimensional Health Locus of Control, as well as the Hospital Anxiety and Depression Scale and patients' medical records were used. Data were analyzed using descriptive statistics, t-test, Pearson's correlation, MANOVA and multiple linear regressions. Women with breast cancer had higher scores on all external HLC subscales, i.e. chance, doctor, powerful others and God, and lower internal HLC compared to healthy women. High God LHC scores were associated with a high level of anxiety (${\beta}=0.21$, p<0.05), whereas none of the HLC subscales were associated with depression. Our results suggest that women with breast cancer tend to have high external HLC, while healthy women tend to have high internal HLC. A strong belief in an external source of control, i.e. God, might be negatively associated with patient emotional adjustment. Further research is needed to give an insight into the direction of this association.