• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.4
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• pp.62-69
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• 2013

Visual demands associated with in-vehicle display usage and text messaging distract a driver's visual attention from the roadway. To minimize eyes-off-the-road demands, voice interaction systems are widely introduced. Under cognitively distracted condition, however, awareness of the operating environment will be degraded although the driver remains oriented to the roadway. It is also know that the risk of inattentive driving varies with age, thus systematic analysis of driving risks is required for the older drivers. This paper aims to understand the age-related driving performance degradation and visual attention changes under auditory cognitive demand which consists of three graded levels of cognitive complexity. In this study, two groups, aged 25-35 and 60-69, engaged in a delayed auditory recall task, so called N-back task, while driving a simulated highway. Comparisons of younger and older drivers' driving performance including mean speed, speed variability and standard deviation of lane position, and gaze dispersion changes, which consist of x-axis and y-axis of visual attention, were conducted. As a result, it was observed that gaze dispersion decreased with each level of demand, demonstrating that these indices can correctly rank order cognitive workload. Moreover, gaze dispersion change patterns were quite consistent in younger and older age groups. Effects were also observed on driving performance measures, but they were subtle, nonlinear, and did not effectively differentiate the levels of cognitive workload.

• Journal of the Korea Computer Graphics Society
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• v.18 no.3
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• pp.17-27
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• 2012

In this paper, we describe a case study of the film 'Sector 7' which was produced by technologies applied fluid simulation. For the CG scenes in the movie which include highly detailed fluid motions, we used smoothed particle hydrodynamics(SPH) technique to express subtle movements of seawater from a crashed huge tank, and used hybrid simulation method of particles and levelsets to describe bursting water from a submarine's broken canopy. We also used detonation shock dynamics(DSD) technique for detailed flame simulations to produce a burning monster, the film"s main character. At this point, the divergence-free vortex particle method was applied to conserve the incompressible property of fluids. In addition, we used an upsampling method to achieve more efficient video production. Consequently, we could produce the high-quality visual effects by using the domestic technologies.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.17 no.4
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• pp.337-349
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• 1995

Periosteum in general is described as a specialized fibrous membrane of mesenchymal origin consisting of two basis layers : outer fibrous layer consists of irregularly arranged dense connective-tissue with fibroblasts, and inner osteogenic or cambial layer is composed of more loosely arranged fibers, greater vascularity and flatted spindle-shaped pre-osteoblasts. This periosteum may serve in controlling bone growth, especially mandibular growth has been emphasized. But, the periosteum enwrapping the facial skeleton have been studied for many years leaving a controversy in opinion regarding the function of these structures. We evaluated the bone formation activity of te periosteum in allogeneic bone grafts which bones are made of freeze-dried preparation preoperatively. We made the calvarial bone defects, 5 ${\times}$ 7mm sized, amd grafted with allogeneic bone in rats, which a half of specimens has dissected the overlying periosteum and a rest intacted. After bone grafting, we evaluated the capacity ofbone formation of periosteum, 1, 2, 4, 6, 8 weeks postoperatively. There are subtle differences of bone formation during early healing period after demineralized allogeneic bone grafting between control groups with periosteum and experimental groups without periosteum.

• Journal of Electrochemical Science and Technology
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• v.11 no.2
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• pp.132-139
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• 2020

Solid oxide fuel cells (SOFCs) are among one of the promising technologies for efficient and clean energy. SOFCs offer several advantages over other types of fuel cells under relatively high temperatures (600℃ to 800℃). However, the thermal behavior of SOFC stacks at high operating temperatures is a serious issue in SOFC development because it can be associated with detrimental thermal stresses on the life span of the stacks. The thermal behavior of SOFC stacks can be influenced by operating or material properties. Therefore, this work aims to investigate the effects of the thermal conductivity of each component (anode, cathode, and electrolyte) on the thermal behavior of samarium-doped ceria-based SOFCs at intermediate temperatures. Computational fluid dynamics is used to simulate SOFC operation at 600℃. The temperature distributions and gradients of a single cell at 0.7 V under different thermal conductivity values are analyzed and discussed to determine their relationship. Simulations reveal that the influence of thermal conductivity is more remarkable for the anode and electrolyte than for the cathode. Increasing the thermal conductivity of the anode by 50% results in a 23% drop in the maximum thermal gradients. The results for the electrolyte are subtle, with a ~67% reduction in thermal conductivity that only results in an 8% reduction in the maximum temperature gradient. The effect of thermal conductivity on temperature gradient is important because it can be used to predict thermal stress generation.

• Journal of Convergence for Information Technology
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• v.10 no.6
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• pp.164-176
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• 2020

Efficient production of antigen specific cytotoxic T cells is critical for appropriate adoptive immune response. In vitro culture and expansion of human T lymphocyte clones are very sophisticated and subtle procedure in immune cell therapy and hard to control. Therefore, many groups devoted their efforts to manipulate artificial antigen presenting cells (aAPCs) that can induce T cell activation and clonal expansion. To mimicking of natural antigen-presenting cells, aAPCs encompass basic signal molecules required for T cell activation: MHC:antigen complexes, co-stimulatory molecules and soluble immune modulating molecules. Orchestrated organization of these molecules is important for efficient T cell activation. Here, we discuss how those molecules have been incorporated in several aAPC models, but also how physical properties od aAPC are important for interaction with T cells.

• Journal of the Korean Society for Nondestructive Testing
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• v.21 no.5
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• pp.518-525
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• 2001

As steam generator (SG) tubes have aged, new and subtle flaws have appeared. Most of them start growing from outside the tubes. Since signals from outer diameter (OD) defects are very weak compared to those from inner diameter (ID) defects in the conventional eddy current testing due to skin effect, this paper studies the feasibility of using remote field eddy current (RFEC) technique, which has shown equal sensitivity to ID and OD defects in the ferromagnetic pipe inspection. Finite element modeling studies show that the operating frequency needs to be increased up to a few hundred kHz in order for RFEC effects to occur in the nonmagnetic SG tube. The proper distance between exciter and sensor coils is also found to be about 1.5 OD, which is half the distance used in the ferromagnetic pipe inspection. Defect signals obtained by the designed RFEC probe show equal sensitivity to ID and OD defects and the existence of linear relationship between defect depth and phase signal strength. These results tell us that RFEC inspection is feasible even in nonmagnetic steam generator tubes.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.1
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• pp.32-38
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• 2005

A long-term study initiated in 1989 at San-born Field, Columbia, Missouri, was designed to evaluate the affect of environmental factors, nitrogen application, and crop rotation on soybean (Glycine max [L.] Merr.) seed composition. Soybeans were grown as part of a four- year rotation which included corn (Zea maize L.), wheat (Triticum aestivum L.), and red clover (Trifolium pratense L.). Results from soil tests made prior to initiation of the study and subsequently every five years, were used to calculate application rates of nitrogen, phosphorus, and potassium necessary for target yield of pursuant crops. In the experimental design, nitrogen was applied to one-half of the plot on which the non-leguminous crop, either corn or wheat was grown. Analysis of soybean seed by near infrared reflectance spectroscopy collected over an 11-year period revealed a linear increase in protein and decrease in oil content. Application of nitrogen fertilizer to non-leguminous crops did not have an apparent effect on total protein or oil content of subsequent soybean crop. Analysis of soybean seed proteins by sodium dodecyl sulfate polyacrylamide gel electrophoresis in conjunction with computer­assisted densitometry revealed subtle changes in the accumulation of seed proteins. Immunoblot analysis using antibodies raised against the $\beta-subunit$ of $\beta-conglycinin$ showed a gradual increase in the accumulation of the 7S components during successive years of the experiment. A linear increase in temperature and decrease in rainfall was observed from the onset of data· collection. Higher temperatures during the growing season have been linked to increased protein and diminished oil content of soybean, thus changes observed in this study are possibly related to climatic conditions. However, crop rotation and subsequent changes in soil ecology may contribute to these observed changes in the seed composition.

• Journal of Fashion Business
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• v.10 no.3
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• pp.78-86
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• 2006

Coffee extract dyeing on silk fabric using various mordanting agents at different mordanting condition was studied in our previous research. Coffee extract dyeing can exert beautiful colors and have several advantages over the conventional natural dyeing. Since most of natural dyes are expensive for mass production, strongly season and source dependent, and hard to store, and therefore, coffee waste was used as natural dye to create beautiful colors in this study. Coffee waste is inexpensive and easy to store, and provide a comparatively regular quality regardless of season and source. The effects of dyeing condition such as dyeing temperature, dyeing time, and liquor ratio on dyeing characteristics of silk fabrics were investigated. Coffee extract dyed silk showed brilliant colors, and the colors were different with the kind of mordant. Cu, Sn, and Al mordanted silks showed golden yellow with subtle change of hue and value, while Fe mordanted silk showed a brownish green color upon coffee extract dyeing. As the dyeing temperature increased, the dyeability generally increased in all mordanted silk fabrics except Fe mordanted silk until $45^{\circ}C$. The dyeing temperature did not affect the dyeability of Fe mordanted silk fabric. As the liquor ratio increased, the dyeability showed a gradual increase in all mordanted silk except Cu mordanted silk. Cu mordanted silk fabric showed an abrupt increase in dyeability at liquor ratio1:150. The dyeing time effect can be separated into 2 stages. During the initial half an hour, the dyeability did not change significantly, and then, increased after 45 min. dyeing time duration. A further increase in dyeing time after 45 min. did not affect the dyeing efficiency in all mordanted silk fabrics except the Cu mordanted.

• Korean journal of communication and information
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• v.57
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• pp.181-201
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• 2012

Classic cultivation theory and research has been noted for its failure to capture subtle variation in effects by genre and to consider tangible and practical dependent variables. Redressing these limitations, this study aimed at extending cultivation theory frame to incorporating fatalistic attitudes and reality television viewing, especially with the mediator of perceived realism. We first replicated the original cultivation effect by showing the significant effect of overall TV viewing. Even controlling for overall TV viewing, reality-based program use showed positive association with fatalistic beliefs; furthermore, the effect remained significant, additionally controlling for news(fact) use and drama(fiction) use. In a nutshell, the cultivation effect of reality-based TV program on fatalistic beliefs turns out quite stable even after controlling other competing genres.

• 한국지구물리탐사학회:학술대회논문집
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• 2008.10a
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• pp.119-124
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• 2008

Due to the recent development of instruments which enabled the measurements of subtle IP effect in the ground and analysis algorithms, complex resistivity (CR) method was expanding its application to various field. In this study, we applied the CR method to the test site where the ground reinforcement had been done by injecting the cement mortar for investigating the effect of ground reinforcement. For this site, resistivity monitoring and tomography survey was carried out while the ground reinforcement had been made by the grouting. From the result, the anomalous region that was shown on the result of resistivity 4D monitoring was coincident with those of phase section in the CR method, because the cement grouting material had the strong IP effects. It might be expected that the CR method should be very powerful surveying tool for the similar purpose.