• ALGAE
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• v.31 no.4
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• pp.379-390
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• 2016

When a multinucleate cell of Bryopsis plumosa was collapsed by a physical wounding, the extruded protoplasm aggregated into numerous protoplasmic masses in sea water. A polysaccharide envelope which initially covered the protoplasmic mass was peeled off when a cell membrane developed on the surface of protoplast in 12 h after the wounding. Transmission electron microscopy showed that the protoplasmic mass began to form a continuous cell membrane at 6 h after the wounding. The newly generated cell membrane repeated collapse and rebuilding process several times until cell wall developed on the surface. Golgi bodies with numerous vesicles accumulated at the peripheral region of the rebuilding cell at 24 h after the wounding when the cell wall began to develop. Several layers of cell wall with distinctive electron density developed within 48-72 h after the wounding. Proteome profile changed dramatically at each stage of cell rebuilding process. Most proteins, which were up-regulated during the early stage of cell rebuilding disappeared or reduced significantly by 24-48 h. About 70-80% of protein spots detected at 48 h after the wounding were newly appeared ones. The expression pattern of 29 representative proteins was analyzed and the internal amino acid sequences were obtained using mass spectrometry. Our results showed that a massive shift of gene expression occurs during the cell-rebuilding process of B. plumosa.

• Journal of Korea Spatial Information System Society
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• v.9 no.1
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• pp.1-13
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• 2007

The necessity of future index is increasing to predict the future location of moving objects promptly for various location-based services. A representative research topic related to future index is the probability trajectory prediction technique that improves reliability using the past trajectory information of moving objects in the road network environment. However, the prediction performance of this technique is lowered by the heavy load of extensive future trajectory search in long-range future queries, and its index maintenance cost is high due to the frequent update of future trajectory. Thus, this paper proposes the Probability Cell Trajectory-Tree (PCT-Tree), a cell-based future indexing technique for efficient long-range future location prediction. The PCT-Tree reduces the size of index by rebuilding the probability of extensive past trajectories in the unit of cell, and improves the prediction performance of long-range future queries. In addition, it predicts reliable future trajectories using information on past trajectories and, by doing so, minimizes the cost of communication resulting from errors in future trajectory prediction and the cost of index rebuilding for updating future trajectories. Through experiment, we proved the superiority of the PCT-Tree over existing indexing techniques in the performance of long-range future queries.

• Korean Journal of Agricultural and Forest Meteorology
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• v.13 no.1
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• pp.41-46
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• 2011

Reliable information on the surface solar radiation is indispensable for rebuilding food production system in the famine plagued North Korea. However, transfer of the related modeling technology of South Korea is not possible simply because raw data such as solar radiation or sunshine duration are not available. The objective of this study is restoring solar radiation data at 27 synoptic stations in North Korea by using satellite remote sensing data. We derived relationships between MODIS radiation estimates and the observed solar radiation at 18 locations in South Korea. The relationships were used to adjust the MODIS based radiation data and to restore solar radiation data at those pixels corresponding to the 27 North Korean synoptic stations. Inverse distance weighted averaging of the restored solar radiation data resulted in gridded surfaces of monthly solar radiation for 4 decadal periods (1983-1990, 1991-2000 and 2001-2010), respectively. For a direct application of these products, we produced solar irradiance estimates for each sub-grid cell with a 30 m spacing based on a sun-slope geometry. These products are expected to assist planning of the North Korean agriculture and, if combined with the already prepared South Korean data, can be used for climate change impact assessment across the whole Peninsula.