• Atmosphere
• /
• v.21 no.4
• /
• pp.337-347
• /
• 2011

In this paper, we developed a detection and correction method of noisy pixels embedded in the time series of normalized difference vegetation index (NDVI) data based on the spatio-temporal continuity of vegetation conditions. For the application of the method, 25-year (1982-2006) GIMMS (Global Inventory Modeling and Mapping Study) NDVI dataset over the Korean peninsula were used. The spatial resolution and temporal frequency of this dataset are $8{\times}8km^2$ and 15-day, respectively. Also the land cover map over East Asia is used. The noisy pixels are detected by the temporal continuity check with the reference values and dynamic threshold values according to season and location. In general, the number of noisy pixels are especially larger during summer than other seasons. And the detected noisy pixels are corrected by the iterative method until the noisy pixels are completely corrected. At first, the noisy pixels are replaced by the arithmetic weighted mean of two adjacent NDVIs when the two NDVI are normal. After that the remnant noisy pixels are corrected by the weighted average of NDVI of the same land cover according to the distance. After correction, the NDVI values and their variances are increased and decreased by 5% and 50%, respectively. Comparing to the other correction method, this correction method shows a better result especially when the noisy pixels are occurred more than 2 times consistently and the temporal change rates of NDVI are very high. It means that the correction method developed in this study is superior in the reconstruction of maximum NDVI and NDVI at the starting and falling season.

• Proceedings of the KIEE Conference
• /
• 1997.07e
• /
• pp.1834-1836
• /
• 1997

In this study, we simulated the developing process of two-dimensional corona discharge using the fluid method in 760 torr. It was assumed that the transport coefficients of nitrogen gas were only the function of local electric field. Discharge mechanisms considered were a Townsend first ionization and a secondary electron emission. We obtained spatio-temporal distribution of electron and ion by calculating continuity equation using FCT algorithm and calculated an electric field distribution considering a space charge.

• Journal of the Korean Geographical Society
• /
• v.48 no.5
• /
• pp.709-727
• /
• 2013

Recently, "aging in place" has become the principle philosophy of elderly housing policy in many countries. However, since there is ambiguity surrounding the universal definition of it, the meaning of AIP has been defined by political expediency. This study aims to discuss the meaning of AIP by examining the transition of elderly housing issues and policy in Japan. During the last two decades, the Japanese government has tried to launch a new elderly welfare system to shift the responsibility of elderly care from the family to the society and from the society to the region. And the focus of elderly housing policy has shifted from the promotion of three-generation dwellings to supporting the development of private residences. However, since the main goal has been limiting the welfare budgets rather than enhancing the quality of life, elderly housing issues have been reduced to a matter of choosing either elderly care facilities frequently located in suburbs or not. This paper suggest that we should pursue the true AIP idea in housing policy, and argues that to do so we need to consider AIP from diverse aspects such as temporal continuity, the range of space, the dynamics of place experience and the capability of communities.