• 한국해양학회지
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• v.21 no.4
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• pp.236-244
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• 1986

This study was carried out for appreciable information on the proper habitats and feeding modes of some dominant polychaetes in the continental shelf of the East Sea during April, 1985. Among 95 polychaete species, we select ed 9 dominant species in terms of their occurring frequency, abundance and population density. These are Terebellides stroemi, Chaetozone setosa, Magelona japonica, Ampharete arctica, Aglaophamus sinensis, Nothria holobranchiata, Lumbrineris japonica, Myriochele gracilis, Notoproctus pacificus. Major food item s of these species are centric diatoms and detritus. The feeding modes of the the m are mainly surtace or subsurface deposit feeding, though two specters, M.holobranchiata and L. japonica, could be assumed to be potential carnivores. To a certain degree, most deposit feeders in the coarse sediments showed selectivity in feeding and tube building. The feeding mode, gut content and the tube structure, and the distribution pattern of dominant polychaetes correspond well with the habitat tharacters, e.g.the bottom topography, the source of food and the sediment composition.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.1
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• pp.10-17
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• 1999

The purpose of this study is to investigate the baroclinic response of the upper-layer of two-layered fluid when the lower-layer motion is driven by pumping an external fluid into the lower-layer or by pumping out the lower-layer fluid. Recent observations of the barotropic nature of deep water movements in the East Sea (fakematsu et al., 1994; KORDI, 1997) may suggest a possibility of interaction between the upper and lower layer via interface tilting. For homogeneous fluid, steady and axisymmetric source or sink causes axisymmetric geostrophic flow, and the lower-layer motion in two-layered fluid was similar to homogeneous flow. But as Rossby number (${\varepsilon}$) or internal Froude number ($f_2$) increases, the lower-layer motion was affected by the interface tilting. The interface tilting calculated based on the observed azimuthal velocities of upper- and lower-layers becomes greater as $f_2$ increases. In other words, the increase of the $f_2$ changes the barotropic system to baroclinic system.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.33 no.7
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• pp.51-58
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• 2005

In 1990, GPS which had been developed for the military purposes became available to the civilian community. Since then these satellite navigation systems have been used extensively in the industrial areas such as car navigation, airplanes, communications, science and surveying. If we are dependent on GPS, however, there are some foreseeable problems in the areas of national security and sovereignty. Current GPS satellite constellation provides limited performance for the country like Korea and Japan where mountain area and urban canyon do not allow the wide skyline. To solve these problems, many countries plan to make other alternative navigation systems.In this paper, RNSS(Regional Navigation Satellite System) is designed to provide communication service with high elevation angle. It is shown, that system does not only have good navigation performance, but also improve GPS performance in Korea and its neighboring areas.

• Journal of Korean Society of Forest Science
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• v.19 no.1
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• pp.49-54
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• 1973

Surveys of stock volume on steep and vast expanse of mountains, involves various difficulties. And it is extremely uneconomical in forest management point of view, to spend lots of time and man power for surveying such tree volume as the value is much cheaper in comparison with volume and weight. Therefore, a stand volume table estimate easely stock volume per hectare basis from aerial photographs was prepared and correlations to stand volume among factors affecting tree volumation, were studied. Data were 114 places selected from planted Korean white pine, Pinus koreiensis Sieb. et Zucc. stands in Kwangnung Experiment Forest and were computed and analysed by the means of the quantification in the multi-variate statistical analysis. Electronic Data Processing System was applied for data processing at Korean Instiute of Science and Technology. Coefficients of multiple correlations of stand volume table was ranged 0.85~0.88.

• Journal of Science and Technology Studies
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• v.14 no.2
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• pp.251-280
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• 2014

Although gender-mainstreaming policies have been implemented, women are still under-represented in Korean science and technology (S&T). It is necessary to systematically analyze successful strategies which improved gender-diversity in S&T institutional environment. This paper examined notable attempts to lessen gender inequality in the fields of S&T education, research and industry. In so doing, the paper makes three important arguments. First, effective strategies for gender-mainstreaming are based upon gender-sensitive analyses of institutional and cultural contexts in S&T. Second, gender-sensitive strategies can contribute not only to gender-diversity but also qualitative and quantitative improvements in S&T. Finally, the paper provides strategies to increase gender-diversity in Korean S&T.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.8 no.4
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• pp.349-356
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• 2003

A continuous monitoring of sedimentation rate and textural characteristics of surface sediments was carried out on the tidal flats in Kwangyang Bay, middle South Sea for two years on an every-two-monthly basis. This study shows that during the winter the tidal flats receive a thin surface layer of which texture becomes finer. In summer, the surface sediments were subject to rather abrupt erosion by occational typhoons and heavy rainfall resulting in a coarse-silt dominated texture. Due to nearly closed geomorphology of Kwangyang Bay, local waves created in the bay during winter are much subdued, in contrast to the rough wave climate and associated sedimentary cycle for open-type tidal flats in the Yellow Sea. In addition, unexpected artificial effects on the tidal-flat sedimentation by construction of a huge industrial complex along the shoreline of the bay are observed from a nearby tidal flat. Here, the sediments were consistently eroded without any sign of natural seasonal variations.

• Journal of the Korean Association of Geographic Information Studies
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• v.12 no.4
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• pp.59-73
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• 2009

In this study, we performed a GIS-based landslide hazard analysis by employing historical landslide data in Korea, coupling with geomorphological, geological, climatic and rainfall data. Based on 596 landslide data from 2001 to 2003, the correlations between landslide occurrence and various factors (elevation, slope angle, slope aspect, soil type and rainfall) that affect the occurrence were estimated by the statistical analysis, zonal statistics. The weights and hazard indices of 6 raster layers were derived from the estimated correlations in order to generate a landslide hazard map by applying raster calculation technique. As a result of this study, GIS technique can be used effectively to incorporate the landslide hazard contributions from various data sets simultaneously.

• Journal of the Korean Association of Geographic Information Studies
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• v.12 no.4
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• pp.158-168
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• 2009

As nation and society progresses, urban ground facilities and their management system get more complicated and the cost and effort to control the system efficiently grows exponentially. This study suggests to the deployment method of a sensor node by Wireless Sensor Network for controling the Urban Ground Facilities of National Facilities. First, we achieve the management facilities and method using the first analysis and then make the coverage of sensing and then set up the Sensor Node in Urban Ground Facilities. Second, we propose the solution way of repetition by the second analysis. And, we embody the GIS program by Digital Map and this method, we improve the reality by overlapping an aerial photo. Also we make an experience on the sensor node allocation using making program. we can remove the repetition sensor node about 50%, and we can confirm that the sensor nodes are evenly distributed on the road.

• Korean Journal of Remote Sensing
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• v.26 no.2
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• pp.209-220
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• 2010

One of the most difficult tasks in measuring oceanic conditions is to produce oceanic current information. In efforts to overcome the difficulties, various attempts have been carried out to estimate the speed and direction of ocean currents by utilizing sequential satellite images. In this study, we have estimated sea surface current vectors to the south of the Korean Peninsula, based on the maximum cross-correlation method by using sequential ocean color images of SeaWiFS chlorophyll-a. Comparison of surface current vectors estimated by this method with the geostrophic current vectors estimated from satellite altimeter data and in-situ ADCP measurements are good in that current speeds are underestimated by about 15% and current directions are show differences of about $36^{\circ}$ compared with previous results. The technique of estimating current vectors based on maximum cross-correlation applied on sequential images of SeaWiFS is promising for the future application of GOCI data for the ocean studies.

• Journal of The Geomorphological Association of Korea
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• v.20 no.4
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• pp.37-50
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• 2013

This study analyzes results of published studies of weathering pits in Korea focusing on tafoni and gnamma and it suggests new types of weathering pits and next subjects through the analysis. 34 papers, published between 1978 and February 2012, have been analyzed and the following are details of the analysis. In terms of the study results, weathering pits are commonly developed on coarse-grained rocks such as granite, but also found on various rocks. Multiple reasons including mechanical, chemical and salt weathering create weathering pits and they are closely related to the geological structure. Weathering pits are classified as tafoni and gnamma but the forms have not been verified. In the future, quantitative analysis must be conducted find the factors influencing creation, forms and development of weathering pits.