• Journal of the korean society of oceanography
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• 제38권4호
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• pp.173-184
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• 2003

Major differences between wind speeds from atmospheric pressure maps (Na wind) and near­surface wind speeds derived from satellite scatterometer (NSCAT) observations over the East (Japan) Sea have been examined. The root­mean­square errors of Na wind and NSCAT wind speeds collocated with Japanese Meteorological Agency (JMA) buoy winds are about $3.84\;ms^{-1}\;and\;1.53\;ms^{-1}$, respectively. Time series of NSCAT wind speeds showed a high coherency of 0.92 with the real buoy measurements and contained higher spectral energy at low frequencies (>3 days) than the Na wind. The magnitudes of monthly Na winds are lower than NSCAT winds by up to 45%, particularly in September 1996. The spatial structures between the two are mostly coherent on basin­wide large scales； however, significant differences and energy loss are found on a spatial scale of less than 100 km. This was evidenced by the temporal EOFs (Empirical Orthogonal Functions) of the two wind speed data sets and by their two­dimensional spectra. Since the Na wind was based on the atmospheric pressures on the weather map, it overlooked small­scale features of less than 100 km. The center of the cold­air outbreak through Vladivostok, expressed by the Na wind in January 1997, was shifted towards the North Korean coast when compared with that of the NSCAT wind, whereas NSCAT winds revealed its temporal evolution as well as spatial distribution.

• Journal of The Geomorphological Association of Korea
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• 제28권3호
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• pp.37-49
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• 2021

Analysis and prediction of storm surges are very important because the global warming has raised sea levels and increased the frequency of massive typhoons, accelerating damage of coastal flooding. However, the data for storm surge prediction is lacking due to the short history of observation in South Korea. The purpose of this study is to investigate the spatial and temporal characteristics of the previous surges and tsunamis based on the historical documents published during the Joseon Dynasty. In addition, we tried to evaluate the damage and spatial extent of such disasters, using the expressions about surge records including heights and number of administrative divisions. As a result, a total of 175 records of surges and tsunamis were compiled from 1392 to 1910: 145 events were extracted through the analysis of the ancient documents, and 30 events were from the previous research. Most of the strorm surges occurred along the west coast during summer season. More than half of the total surges were concentrated for 120 years from the mid 1600s to the mid 1700s, which was estimated to be highly relevant to the climate conditions in East Asia during the Little Ice Age. Hazardous areas by storm and tidal surges were also extracted, including Asan, Ganghwa, and Siheung during the Joseon Dyanisity period.

• 한국해양학회지
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• 제26권1호
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• pp.47-58
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• 1991

To study the spatio-temperal distribution of the ichhyoplankton in the estuarine ecosystem, Ichthyoplankton were sampled with associated data on water temperature and salinity in Mankyong-Dongjin Estuary on October, 1989, and March, May and July, 1990. Water temperature varied seasonally, showing homogeneous spatial pattern. The spatial difference in splinty was determined by the amount of river runoff. Few Ichthyoplankton occurred in October and March. In May, Konosirus punctatus occupied most of the ichthyoplankton. In July, Sardinella zunasi, Engraulis japonica, Gobiidae, and Thrissa sp. were the dominant species. The eggs and larvae of Engraulis japonica were collected from the outer bay, while those of Konosirus punctatus predominated in the less saline inner bay. Konosirus punctatus. Sardinella zunasi, Gobiidae, and Thrissa sp. were the characteristic species of this estuary. They were considered to be spawned and grown during their early life stage in the less saline water.

• Korean Journal of Microbiology
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• 제30권3호
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• pp.187-192
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• 1992

The spatial and temporal distribution of petroleum-degrading bacteria(PDB) was studied at six sampling sites in Kyeonggi Bay of the Yellow Sea fiom March 1990 to October 1991. In addition, petroleum-degrading potcntial of natural ~iiai-ineb acterial population was studied at different culturc contlitions. During the period o f stutly. thc heterotrophic bacterial number and PDB number were n1e;rsured in the range of 7 000-108.400 CFU/nil. 0-2.800 MPN1100 mi. respectively. The spatial tlistribution of PDB wa\ highly affected by presence of petroleum hydrocarbon. In laboratory cxperirncnt. petrolcu~n biodegradation wac enhanced hy addition of yeast cxtracl. cell free cxtr:~ct. anti rnixctl culture of PI)B.

• Journal of ILASS-Korea
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• 제18권1호
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• pp.27-34
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• 2013

A preburner is one of the key components for a staged combustion cycle engine fueled by kerosene and Lox. Since it has oxygen rich combustion inside, temperature control is very crucial. The temperature of the exhaust gas should be low enough not to burn turbine blade and yet high to keep the efficiency high. In addition temporal and spatial deviations also managed strictly. Conventionally, the required average and maximum temperature are determined by engine system and the preburner should be developed to meet the criteria. Currently being developed preburner has 50K spatial temperature deviation requirement. It was estimated by numerical simulations and proven by tests. The numerical analysis were done with both supercritical condition and normal conditions. The tests results showed that the temperature deviations were less than expected, and the results from the test and simulations were well agreed when the supercritical conditions were considered. Above all, since the gas temperature created by the preburner is very stable with minimum deviation, the preburner developed can be used to drive a turbine and for gas-liquid combustion chambers.

• Spatial Information Research
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• 제11권3호
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• pp.227-240
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• 2003

The primary focus of this study is to provide a general methodology which can be utilized to understand and analyze environmental issues such as long term ecosystem dynamics and land use/cover change by development of 2D dynamic landscape models and model-based simulation. Change processes in land cover and ecosystem function can be understood in terms of the spatial and temporal distribution of land cover resources. In development of a system to understand major processes of change and obtain predictive information, first of all, spatial heterogeneity is to be taken into account because landscape spatial pattern affects on land cover change and interaction between different land cover types. Therefore, the relationship between pattern and processes is to be included in the research. Landscape modeling requires different approach depending on the definition, assumption, and rules employed for mechanism behind the processes such as spatial event process, land degradation, deforestration, desertification, and change in an urban environment. The rule-based models are described in the paper for land cover change by natural fires. Finally, a case study is presented as an example using spatial modeling and simulation to study and synthesize patterns and processes at different scales ranging from fine-scale to global scale.

• Journal of the Korean Geographical Society
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• 제37권2호
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• pp.131-142
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• 2002

The community and communal folk belief are developed as spatial phenomena. So the communal folk belief express the spatial perception of inhabitants in traditional village. This study analysis the spatial characteristics of communal folk belief in traditional village. The study area is Bangchon village which consists of seven hamlets in Changhung-gun, Chollanam-do. The reset are as follows. First, the seven hamlet\`s location process in Bangchon village has been developed with spatio-temporal variations since Korea dynasty. Second, the communal folk belief in study area can be classified as Ipsok, Byolsinje\`s site, Hojeby\`s site. Third, the spatial characteristics of communal folk belief in study area are indication of each hamlet\`s boundary, indication of entrance and exit of Bangchon visage, indication of central space of Bangchon village in traditional period. Consequently, the spatial distribution of communal for belief are important indicator about spatial structure and spatial perception in traditional village\`s society.

• Journal of Korean Society of Environmental Engineers
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• 제37권6호
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• pp.380-386
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• 2015

In this study, the spatial and temporal distribution of volatile organic compounds (VOCs) in an industrial shipbuilding complex was monitored, and the local characteristics estimated. The major VOC component measured at all of the sampling sites were almost the same as those found at an indoor painting facility, indicating that painting works conducted in the shipyards were a significant source of VOCs in the vicinity of shipbuilding areas. The main parameters affecting the VOCs distribution were the distance between the sampling site and painting work place, and the intensity of the painting works. A quite broad range of VOC concentrations were observed in all of the sampling sites, depending on the intensity of painting works in nearby areas suppressing the typical seasonal and temporal variation trends in VOCs observed in urban areas.

• Journal of the Korean Association of Geographic Information Studies
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• 제3권4호
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• pp.73-86
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• 2000

This study focused on extracting an efficient method in the fruit cropping distribution mapping with various classification methods using multi-temporal satellite images and Geographic Information Systems(GIS). For this study, multi-temporal Landsat TM images, in observation data and existing fruit cropping area statistics were used to compare and analyze the properties of fruit cropping and seasonal distribution per classification method. As a result, this study concludes that Maximum Likelihood Method with earlier autumn satellite image was most efficient for the fruit cropping mapping using Landsat TM image. In addition, it was clarified that cropping area per administrative boundary was prepared and distribution pattern was identified efficiently using GIS spatial analysis.

• Journal of the Korean Geographical Society
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• 제38권5호
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• pp.835-848
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• 2003

This study deals with the spatio-temporal change of land cover and vegetation distribution between 1988 and 2001 using remote sensing images and CIS techniques in west area of Pyeongbuk Province, northwest Korea. Landsat TM and ETM images are geometrically and radiometrically corrected for the analysis of land cover and NDVI. Forested areas are decreased during 13 year from 1988 to 2001 in study area including Sakju, Daegwan, Guseong and Euiju of Pyeongbuk Province, because wasteland are increased by human impact and denuded land by landslide and flooding. DEM analysis presents that settlement and cropland are developed toward higher and steeper mountain slope, together with decrease NDIV values. these changes have resulted from unplanned increase of cropland without consideration of geomorphic condition. Therefore, more researches and reasonable policies are required to protect forest and cropland and stable food supply against natural hazard like landslide.