• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.3
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• pp.150-160
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• 1988

Food habits of Alaska plaice, Pleuronectes quadrituberculatus, and ecological interactions of this species with yellowfin sole, Limanda aspera, and rock sole, Lepidopsetta bilineata, in the eastern Bering Sea were studied. Alaska plaice mainly feed on polychaetes regardless of sex and size of fish. However, it was shown that food differed by sampling area. Feeding did not occur at night. Food competition seems to be negligible among the three shallow water fiatfish species inhabiting the eastern Bering Sea due to differences in food spectra or spatial distribution.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2000.11a
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• pp.16-19
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• 2000

We propose a deterministic vector channel simulation model satisfying not only rigorous temporal correlation but also arbitrary spatial correlation using the method of Doppler phase difference sampling. The model is more efficient than the conventional PN filtered Gaussian model with coloring process in evaluating the laboratory performance of mobile communication systems employing adaptive way antennas or space diversity.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.285-288
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• 2002

We propose the use of synchronously moving micro-optics (lenslet arrays) for image pickup and display in three-dimensional integral imaging to overcome the upper resolution limit imposed by the Nyquist sampling theorem. With the proposed technique, we present an all-optical three-dimensional integral imaging projector. An optically addressed spatial light modulator is used, which potentially provides better image resolution than the conventional CCD and liquid crystal display pair. We present experimental results using a liquid crystal light valve.

• Journal of Biomedical Engineering Research
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• v.5 no.1
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• pp.25-32
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• 1984

In this paper a new "limited view frequency correlation algorithm" for diffraction topography is proposed. In this algorithm the problem of limited view sampling is solved by spectrum of spatial frequencies of refractive index. This algorithm is very important in a view of reduction of scanning time and improvement of considerably higher image quality object reconstruction.struction.

• Proceedings of the Optical Society of Korea Conference
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• 2001.02a
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• pp.80-81
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• 2001

우주에서 작동이 검증되었고 영상 품질이 잘 알려진 기존 위성 전자광학 결상계들의 MTF 특성을 분석하여 위성 전자광학 결상계 설계에서 실제로 적용될 수 있는 최적화된 MTF 성능 지표를 구하는 방법을 제시하였다. KOMPSAT-1 EOC와 IKONOS에 대해 이론적 한계가 잘 알려진 MTF 성분들인 광학회절한계 MTF와 Spatial 및 Temporal Sampling MTF를 분석하여 실용적인 MTF 성능 지표를 구하였고, 이 지표를 이용하여 몇 가지 광학계의 최소 구경을 추정하여 지표의 실용성을 검토하였다. (중략)

• Journal of Soil and Groundwater Environment
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• v.11 no.3
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• pp.52-58
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• 2006

Kim and Lee (2005) suggested Minimum Entropy Deconvolution (MED) to estimate the temporal sequence of the relative recharge. However this study by Kim and Lee (2005) was just related to the verification of the conceptual approach with MED. In this study, we try to characterize the applicability of MED in the case of spatially heterogeneous recharge (distance from recharge area). Simulated results were recorded with some specific sampling points. Estimated results from this study show higher than 0.8 in cross-correlation with the original recharge sequence. In addition, the physical and mathematical meanings of the applied filter length was also investigated. It was revealed that the length of filter is highly related to the spatial distance between recharge area and the monitoring site, and the apparent shape of hydraulic head change.

• Journal of Environmental Impact Assessment
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• v.20 no.6
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• pp.879-890
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• 2011

The GOSAT (Greenhouse gases Observing SATellite) data provide new opportunities the most regionally complete and up-to-date assessment of $CO_2$. However, in practice, GOSAT records often suffer from missing data values mainly due to unfavorable meteorological condition in specific time periods of data acquisition. The aim of this research was to identify optimal spatial interpolation techniques to ensure the continuity of $CO_2$ from samples taken in the North East Asia. The accuracy among ordinary kriging (OK), universal kriging (UK) and simple kriging (SK) was compared based on the combined consideration of $R^2$ values, Root Mean Square Error (RMSE), Mean Error (ME) for variogram models. Cross validation for 1312 random sampling points indicate that the (UK) kriging is the best geostatistical method for spatial predictions of $CO_2$ in the East Asia region. The results from this study can be useful for selecting optimal kriging algorithm to produce $CO_2$ map of various landscapes. Also, data users may benefit from a statistical approach that would allow them to better understand the uncertainty and limitations of the GOSAT sample data.

• Transactions of the Korean Society of Mechanical Engineers
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• v.10 no.3
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• pp.326-334
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• 1986

The effects of flow interaction between adjacent sprays in twin-spray system on the spatial distribution of injected liquid (water) and drop size distribution in condensable (steam) environment were carefully observed through experiments. The spatial distribution of injected liquid in twin-spray system appears to be more uniform than the simple superposition of the spatial distributions of liquid obtained from each individual spray. Drop size distribution was obtained by using the immersion sampling technique. It was found that, in the twin-spray, the larger numbers of small drops are collected throughout the spraying region due to the increase of entrainment velocity of ambient steam compared with the case of simple superposition of each individual spray. Moreover, in the overlapped portion of the twin-spray, the drop size distribution was changed also due to the collision between large drops. As a result, the behavior of twin-spray system (and eventually multiple-spray system) can not be predicted precisely by simple superposition of the behaviors of each constituting spray. Hence, for the design of multiple spray system, the effect of flow interaction between sprays should be taken into account seriously.

• Journal of Korean Society for Geospatial Information Science
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• v.3 no.1 s.5
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• pp.123-137
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• 1995

The digital information of Land is very important as the basis of geo-spatial information system. And the necessity of it is also increasing. But these days, every other institute that is needing digital map is seperately digitalizing lsnd information. So we need the stadard of accuracy evaluation and the method of hypothesis test for it. In this study, we check the standards of foreign countries and compare and analyze with our country's. After doing it, we suggest the direction for standard of digital map and statistical methods for testing accuracy evaluation about total maps that is digitized. Using hypergeometric distribution for considering consumer risk and producer risk, the statistical test can be for deciding optimal sampling map numbers by the total map and the agreement of contacting parties.

• ALGAE
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• v.26 no.1
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• pp.41-50
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• 2011

Yellow Sea surface sediment samples collected on October 15-31, 2003 were analyzed using the palynological process to investigate the spatial distribution of dinoflagellate resting cysts. The sampling areas comprised four latitudinal transects, the northernmost of which was located off the Shandong Peninsula, China and the southernmost off Jeju Island, Korea. Each transect line was composed of six to nine stations, spanning the distance between the Chinese and Korean coasts. Twenty-five different types of dinoflagellate cysts were identified. Gonyaulax scrippsae, Alexandrium spp. (ellipsoidal type), and G. spinifera were the most dominant at all stations surveyed. Dinoflagellate cysts belonging to the Gonyaulacales comprised over 50% of all cysts collected. The latitudinal distribution trend showed that cyst concentrations along the two middle transects were much higher than those along the two northern and southern transects. Cyst concentrations in the offshore central areas reached their highest values within each transect and gradually decreased toward the Chinese and Korean coasts. Overall, cyst concentrations were markedly elevated in the offshore central Yellow Sea areas and gradually decreased outward in all four directions. This concentric cyst distribution pattern was consistent with the hydrographic features of the Yellow Sea, such as circular current systems, sedimentary properties, and water depth.