• Korean Journal of Remote Sensing
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• v.39 no.5_1
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• pp.729-741
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• 2023

The Operational Linescan System (OLS)sensor is a sensor aboard satellites launched through the Defense Meteorological Satellite Program (DMSP) that detects light in the visible and infrared bands emitted at night. Studies by several researchers have shown a high correlation between nighttime light data from OLS sensors and gross domestic product values. In this study, we investigated the correlation of nighttime light data with the total amount of individual land prices, which is one of the various indicators related to economic development. The study found that most cities and provinces showed a high correlation with a correlation coefficient of more than 0.7, and the correlation coefficient of 0.7837 between the total amount of individual land price and nighttime light data for the entire South Korea was also high. However, unlike other cities and provinces, Seoul has a low correlation coefficient of 0.5648 between nighttime light and the total amount of individual land price, which is analyzed as a reason that the digital number value of the OLS sensor is close to the maximum value and cannot show further brightness changes. This study is expected to help identify announced land prices in areas where announced land prices are not systematically organized and to analyze land use changes in such areas.

• Bulletin of the Korean Space Science Society
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• 2003.10a
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• pp.81-81
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• 2003

We report the plasma blob events that were observed from KOMPSAT-1 (2250 LT, 685-km altitude) and from DMSP F15 (2130 LT,840-km altitude) in the low-latitude ionosphere. The global distribution of blobs showed a season-longitudinal dependence similar to the distribution of the equatorial plasma bubbles, although they were observed along the ${\pm}$15 dip latitudes. The blobs drifted upward relative to the ambient plasmas, and the electron temperatures and H+ proportions were lower within the blobs compared to those in the background. These characteristics of the plasma blobs are very similar to the characteristics of the equatorial plasma bubbles. Then, we suggest that the blobs were originated from the lower altitudes by the mechanism that drives an upward drift of the plasma bubbles. The blob events did not occur in a correlated way with the magnetic activity or daily variation of the solar activity.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.126.1-126.1
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• 2012

The middle-latitude ionization trough, the plasma density depletion in the subauroral region, has been extensively studied since its discovery in the 1960s. Our knowledge of the variability of the trough is mostly based on the observations in the northern hemisphere. Recently, the COSMIC observations enabled the investigation of the trough in both hemispheres at all local time. However, the investigation was limited to the period of the low solar activity. In this study, we investigate the variability of the trough location and morphology with local time, solar cycle, magnetic activity, and interplanetary magnetic field. For this purpose, we analyze the DMSP F15 data acquired during 2000-2010.

• Bulletin of the Korean Space Science Society
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• 2007.10a
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• pp.75.2-75.2
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• 2007

• Journal of the Korea Institute of Information and Communication Engineering
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• v.6 no.6
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• pp.812-818
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• 2002

Spatio-temporal distributions of nighttime fishing fleet are descirbed with the aid of geographic information system(GIS) technology in the East/Japan Sea, using daily mean composite images of the Defense Meteorological Satellite Program(DMSP) /Operational Linescan System(OLS) in 1993. We selected a study area from $30^{\circ} N to 44^{\circ} N in latitude and from 124^{\circ} E to 142^{\circ}$ E in longitude in order to describe the monthly and seasonal changes of nighttime fishing fleet. The GIS software package Image Analyst (ArcView 3) are used to analyze spatio-temporal distributions of fishing nut. And the OLS images of nighttime visible band provide useful information about the spatio-temporal distribution of the fishing nut. Density areas of nighttime fishing fleet are around Tsushima/korea Strait. the east coast of the Korea Peninsula, the coast of Honshu, and around Yamato Bank.

• Bulletin of the Korean Space Science Society
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• 2006.10a
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• pp.106-106
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• 2006

• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.437-440
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• 2005

We examined the relationship between the 50m temperature estimated by remote sensing sea surface temperature (SST) and fishing ground (squid fishing ground) detected by nighttime visible channel defense meteorological satellite program (DMSP) I operational linescan system (OLS) images in the East/Japan Sea during 1993-2000. The results are as follows: The numbers of nighttime fishing boat were distributed the highest in October, and the lowest in April during this study. A nighttime fishing grounds have concentrated in the East Korea Warm Current region, coastal regions of Honshu Island, and Polar front region. Fishing grounds have distributed $11-18^{\circ}C$ of estimated 50m temperature from the satellite data. Relationship between estimated 50m temperature and the distributed fisheries boats showed that the north boundaries of fishing grounds have distributed the temperature of below $12^{\circ}C$ from 1996 to 2000 and that of $13-15^{\circ}C$ during 1993-1995 and 1997-1999. Stable fishing grounds appeared near the Korea/Tsushima Strait from January to March. The center of fishing grounds in spring (April-Jun) have moved to the northward than that in winter, and variations appeared largely in winter. In summer (July-September), center of fishing grounds have formed near the Uleung Island in the south east coast of Korea, and in autumn maximum fishing ground appeared in October, the fishing ground southward from November.

• Journal of Astronomy and Space Sciences
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• v.19 no.2
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• pp.133-140
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• 2002

Space Physics Sensor onboard the KOMPSAT-1, which was launched at 1999, had transmitted ionospheric data during the solar maximum from June 2000 to August 2001. When the KOMPSAT-1 has passed the equatorial region, equatorial bubbles, in which the electron density abruptly decreases, had frequently been detected. Statistical analysis of the data obtained during the entire operational period shows equatorial bubbles frequently occur across the Atlantic region where the geomagnetic field strength is weak. Also, equatorial bubbles occur more frequently for lower Kp index. The results are in good agreement with the previous observations by DMSP satellites and radio experiments at the Peruvian sector The correlation between electron density and the electron temperature shows various behaviors from event to event.

• Ocean and Polar Research
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• v.27 no.2
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• pp.197-203
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• 2005

Dimethylsulfide (DMS) is the most abundant form of volatile sulfurs in the ocean. Many biogeochemical studies have been conducted in the past several decades to unveil the processes driving the production, transformation and removal of DMS. They have shown that the Southern Ocean is an area with one of the highest levels of DMS concentrations during the austral summer in the global oceans. It has recently been observed that Antarctic krill, Euphausia superba, produces DMS and dissolved dimethyl-sulfoniopropionate (DMSP) in its gazing process. Copepods also produce DMS, and the potential production rates of DMS in the Southern Ocean by krill and copepods are estimated to be as much as $21{\mu}mol\;m^{-2}d^{-1}$ and $0.6{\mu}mol\;m^{-2}d^{-1}$, respectively. These production rates of zooplankton and the presence of phytoplanktot which have high DMSP contents in their cells, might facilitate in situ DMS production in the Southern Ocean.

• Bulletin of the Korean Space Science Society
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• 2009.10a
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• pp.38.3-39
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• 2009

Equatorial Plasma Bubble (herafter, EPB) is a common feature in low-latitude F-region during the night time. Since EPB causes significant impacts on the satellite communication and navigation systems, its accurate forecast is highly demanded by the GNSS users. Thus, further understanding of these features and their configuration is a challenging issue in space weather studies. The day-to-day variability of the plasma bubble activity was investigated by analyzing the TIMED/GUVI, ROCSAT-1, DMSP, and CHAMP satellite data. The pre-reversal enhancement (PRE) is known as the most important single parameter for the onset of plasma bubbles but we do not know yet to what extent the day-to-day variability of the bubble activity can be attributed to the PRE. We obtained the magnitude of the PRE from ROCSAT-1 and the occurrence of bubbles in relation to the PRE was investigated by using the coincident observations of EPBs from TIMED/GUVI, DMSP, and CHAMP. By conducting one-to-one comparison of the PRE characteristics with the EPB occurrence we examined the role of the PRE in the onset of EPBs.