• 한국해양학회지
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• v.28 no.4
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• pp.339-346
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• 1993

Due to the natural increase of human population and the concentration of industrial complexes to coastal area, the uses of nearshore area were increased drastically, and the tendency will not stop for a while. Therefore, the loss of human life and property damages of the present days for a disaster of the same magnitude should be heavy as compared to those of the past. For the better utilization of the sea and the prevention of the frequent marine natural and man-made disaster, and for the preparedness for the ocean pollutions, through ocean researches are required. the circulation, tidal currents, storm surges, sea surface wind, waves and sea fogs of the Yellow Sea should be investigated first from the oceanographic point of view, and then the dispersion and diffusion of spilled oil and pollutants, beach erosion, red tide, and longterm sea level oscillations can be studied. International cooperation is crucial for the investigation of the sea because of the temporal and geographic scales of the oceanic phenomina.

• Proceedings of the KIEE Conference
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• 2002.11a
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• pp.102-105
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• 2002

ADSS(All Dielectirc Self-Supporting) cable installed under high voltage power cable line suffers a variety of environmental influence, rain, wind, snow fall, chemical pollution, salt fog and electrical stress. Its lifetime is required to be at least 20 years with this harsh weathering condition. The electrical stress under high voltage power line gives rise to dry band arcing and tracking, the severest damage, on the outer sheath of cable. Finally tracking might penetrate sheath and cause the break-down of ADSS cable. Tracking resistant sheath material, therefore, should be used to protect the core of ADSS from dry band arcing and to be sure long lifetime. In this work, we discuss various commercial tracking resistant material to investigate the way of track resistance and compare their mechanical, electrical, weathering and tracking properties through serial experiments. We found track resistant material is categorized into two main type : polyethylene with metal hydroxide and polyethylene with reduced carbon black. The Liquid contaminant, Inclined plane Tracking and Erosion test says the time to track of tracking resistant material with metal hydroxide has a little longer time to track in the high applied voltage than that with carbon black, but mechanical and weathering properties were inferior to.

• Journal of The Geomorphological Association of Korea
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• v.19 no.2
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• pp.69-79
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• 2012

The aim of this study is to analyze the mid-term changes of beach and dune morphology at Sohwang beach, Korea using by Total Station. Measurements executed 4 times during two year. Based on ArcInfo as point cloud obtained through precise measurement data by Total Station, alteration of beach and dune was analyzed at DEM, of which cell size is about 1m. Since these artificial constructions have influenced current systems of this region, the large-scale sand movements above mentioned have occurred around the jetty and the sea-wall. There occurred sedimentation in the north of the Jetty and erosion in the south of the Jetty, which is installed at the central part of object area. The direction of recent topographic development does not coincide with that of wind, and, rather, topographic changes occurred mainly at beaches and dunes due to the transformation of coastal water flow caused by artificial structure nearby. If precise measurement is conducted periodically, and long term monitoring is carried out by installing equipment measuring movement pattern of sediment around artificial structure, cause of topographic change around the object area could be discovered.

• Journal of Climate Change Research
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• v.2 no.3
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• pp.191-201
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• 2011

This study investigates how green infrastructure, including natural and open space such as forests, rivers, parks, and streets, could effectively counteract climate change in terms of mitigation and adaption, respectively. As a result, green infrastructure, such as forests, parks, vegetable gardens, roof gardens, pedestrian walkways, bike lanes, etc, could effectively mitigate climate change: 1) Carbon storage and sequestration; 2) Fossil fuel substitution; 3) Material substitution; 4) Food production 5) Reducing the need to travel by car. Secondly, green infrastructure, such as rivers, tree-lined streets, farmland, wetlands, dunes, wind ways, etc, could adapt to climate change: 1) Managing high temperatures; 2) Managing water supply; 3) Managing ravine flooding; 4) Managing costal flooding; 5) Managing surface water; 6) Reducing soil erosion; 7) Helping other species to adapt.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.4D
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• pp.561-567
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• 2008

In this study, shoreline change was analyzed by RTK-GPS and advanced airborne LiDAR survey. For extraction of coastline, first of all, tide correction was conducted at all RTK-GPS points through the comparing with the corresponding tidal height, and cross section providing coastline was produced using Autocad Civil3D program. Comparing with two results of RTK-GPS (first, 29 Aug 2007; second, 6 Oct 2007) surveys, coastline of the first result had been decreased about 21m compare with that of the second. And it was also demonstrated that the length of coastline by the first RTK-GPS was 15m shorter than that by the airborne LiDAR survey (Dec. 2006). In addition, we recoquized that the erosion appeared in the top right-hand (dock area); the sediment in the bottom left-hand (Chosun beach area) of the Haeundae beach. As a result, therefore, it was learned that artificial sand filling for beach open and natural effects such as a typhoon, current drift, wind direction gave cause for area changes and coastline.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.6
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• pp.687-697
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• 2019

By monitoring sediment grain size and level variation of tidal flat surface for 6 years (2005-2011), and also by mooring TISDOS (tidal-flat sediment dynamics observation system) on the low intertidal flat in 2008, we investigated the sedimentary environment of tidal flat in the dammed Yeongsan River Estuary. The tidal flat of the Yeongsan River Estuary lost 82 % of its area because of coastal development projects, and a narrow tidal flat below mean sea level now remains. Most of the tidal flat sediments are composed of silt up to 70-94 %, and show the characteristics of clay deficiency and silt dominance. This is closely related with the coastal development, which led to the destruction of high tidal flats where most mud settled, and the modification of tidal current patterns. Moreover, the estuarine tidal-flat sediments reveal seasonal variation. They are coarse with abundant silt during windy autumn to spring, fine with abundant clay during the less-windy and high-discharge summer. This phenomenon indicates that the behavior of sediment particles on the low intertidal flats of the Yeongsan River Estuary is influenced by wind waves for silt and fresh water discharge and the tidal process for clay. Monitoring results of the altitude of tidal flat surface showed that the study area had eroded at an average rate of -2.6 cm/y during the period of 2005-2011, and also that an unusual deposition with a rate of 4 cm/y occurred in 2010. The erosion can be explained by an increased tidal amplitude and a strengthened ebb-dominant tidal asymmetry after the construction of an estuary dike and the Yeongam Kumho Seawall. The deposition in 2010 seems to have been closely related to the mass production of suspended materials from dredging of the estuary.

• Journal of Korean Society of Forest Science
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• v.73 no.1
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• pp.63-69
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• 1986

In general, the snow injury in forestry is an unusual disaster. The degree of snow injury varies greatly depending on stand density and the local topography. This study was conducted to investigate the snow injury in analyzing the demaged by snow-fall in Jinju, Gyeongsangnamdo. The results obtained were summarized as follow; Among 466 total damaged trees, 425 trees were broken and 41 trees were uprooted, the ratio of damage were 5.22%, 2.49%, 0.92% and 0.2% for Pinus densiflora, Pinus thunbergii, Pinus rigida, Alnus hirsuta respectively. The 95% of the damage trees were in the range of 3 to 11 m for height and in the range of 3 to 20 cm for D. B. H.. The directions of the damage trees had a large influence by direction of the wind, but they shown at high tendency to aspect of the slope relatively. The 82% of the damaged trees ranged from 11 to 24 age. The ratio of broken height ($H_B/H$) indicated that the damage was most frequent in the part of stem as 24%, 45%, 31% in the part of the root collar (0.1), stem (0.2-0.4), crown (0.5-1.0) respectively. In general, trees with stem-form coefficient ($H_B/D$) over 0.7-0.8 are apt to suffer by snow damage. The average of stem-form coefficient of trees in this area was 1.06. Therefore, the ratio of damage was high tendency as 3.14%. These results indicate that it is necessary to apply pertinent tending which will increase in resistance of snow damage. As avalanches from the flank of soil erosion rise in an importance matter in present, it should also be considered to measures for prevention and restoration.

• Journal of Korean Society of Forest Science
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• v.90 no.1
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• pp.90-104
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• 2001

This study is aimed to analyze and to evaluate the revegetation and soil conservation technology in desertification-affected sandy land, resulting from the project of "Studies on the desertification combating and sand industry development". Main native plants for combating desertification : The general characteristics of vegetation distribution in desertified regions are partially concentrated vegetation distribution types including the a) desert plants in low zone of desert or sanddune of depressed basin, b) salt-resistant plants around saline lakes, c) grouped vegetation with Poplar and Chinese Tamarix of freshwater-lakes, saline-lakes and river-banks, d) gobi vegetation of gravel desert and e) grassland and oasis-woods around the alluvial fan of rivers, etc. Generally, Tamarix ehinensis Lour., Haloxylon ammodendron Bunge., Calligonum spp., Populus euphratica Oliver., Elaeagnus angustifolia L., Ulmus pumila L., Salix spp., Hedysarum spp., Caragana spp., Xanthoceras sorbifolia Bunge., Nitraria tangutorum Bobr., Lespedeza bicolor, Alhagi sparsifolia Shap., Capparis spinosa L., Artemisia arenaria DC., etc. are widely distributed in desertified regions. It is necessary for conducting research in the native plants in desertified regions. Analysis of intensive revegetation technology system for combating desertification : In the wind erosion region, the experimental research projects of rational farming systems (regional planning, shelterbelts system, protection system of oasis, establishment of irrigation-channel networks and management technology of enormous farmlands, etc.), rational utilization technology of plant resources (fuelwood, medicinal plants, grazing and grassland management, etc.), utilization technology of water resources (management and planning of watershed, construction of channel and technology of water saving and irrigation, etc.), establishment of sheltetbelts, control of population increase and increased production technology of agricultural forest, fuelwood and feed, etc. are preponderantly being promoted. And in water erosion region, the experimental research projects of development of rational utilization technology of land and vegetation, engineering technology and protection technology of crops, etc. are being promoted in priority. And also, the experimental researches on the methods of utilization of water (irrigation, drainage, washing and rice cultivation, etc.), agricultural methods (reclamation of land, agronomy, fertilization, seeding, crop rotation, mixed-cultivation and soil dressing works, etc.) and biological methods (cultivation of salt-resistant crops and green manure and tree plantation, etc.) for improvement of saline soil and alkaline soil in desertified-lands are actively being promoted. And the international cooperations on the revegetation technology development projects of desertified-lands are sincerely being required.

• Korean Journal of Environmental Biology
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• v.35 no.3
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• pp.380-388
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• 2017

Factors affecting spatial distribution of halophytes were analyzed in June 2012 at the Goraebul coastal dunes. In the Goraebul sand dune, distribution of halophytes was divided into three groups. The first group belonging to Elymus mollis, Carex kobomugi, Calystegia soldanella, Ixeris repens and Glehnia littoralis was distributed in the ridge of primary sand dune and dune slack. The second group belonging to Lathyrus japonicus and Zoysia macrostachya was distributed in the dune slack. The third group belonging to Pinus thunbergii, Vitex rotundifolia and Linaria japonicus was distributed in the pine forest of the secondary sand dune. E. mollis, C. kobomugi, C. soldanella, I. repens and G. littoralis was distributed in relatively unstable habitat of sand dunes due to the large amount of sand movement. V. rotundifolia was distributed in a relatively stable habitat. Factors that have the greatest influence on distribution of halophytes in the Goraebul sand dunes are distance from the seashore, topography, and the pine forest. The Goraebul sand dune is a relatively well-preserved area with minimal human intervention. Therefore, different distribution of physico-chemical factors by natural processes is essential to spatial distribution of halophytes than other sand dunes in Korea. Significant natural processes in the Goraebul sand dunes were advance and retreat of coastlines from waves, erosion and sedimentation of sand due to wind and waves, and dispersal of seawater.

• Journal of the Korean earth science society
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• v.27 no.2
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• pp.221-235
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• 2006

In order to understand the transport mechanism of tidal beach sediments in Deukryang Bay, south coast of Korea, beach profiles, surface sediments, sedimentation rates and hydrodynamic conditions have been investigated. The beach is composed of a steep beach face and gentle low-tide terrace, showing general morphologic characteristics of tide dominated beach. Central beach face of an indented coast becomes flattened in summer, but ridge and runnel system developed in other seasons makes the beach profile rather irregular. These seasonal variations of beach profiles and sedimentation rate indicate that beach sedimentation is mainly controlled by both tide and wave processes. Erosion is prevalent in winter when strong wind wave is dominant, while deposition is dominant in other seasons. However, central beach showed an apparent erosional phase in summer. This is caused by strong waves induced by southerly strong winds occurring ephemerally during the summer. On the other hand, sedimentation rates are -89.2 mm/yr on the central beach and 60.5 mm/yr and 38.2 mm/yr on the sides. This result suggests that sediments are eroded on the central beach and subsequently transported to the both sides. Therefore, the central part of Sumun beach, used as a beach bathing site, will be continuously eroded, if nearby dyke continues to prevent the sediment supply from sources.