• Korean Journal of Geomatics
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• v.2 no.1
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• pp.57-64
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• 2002

Measuring the depth of water is very important in ensuring the protection and safety of seaside. There are many difficulties in making the contour bathymetric map, and contour line due to the limitation of continuous measurement of water depth and collimation with the conventional measuring and positioning methods. But the real-time kinematic GPS (RTK GPS) positioning using a carrier phase enables us to decide a precise position without breaking a signal even under the condition of a moving environment. It is also possible to obtain an accurate depth of water in real time with a fathometer through the measuring of time delay between sending and receiving epochs. This research aims at investigation of accuracy potential of RTK GPS in combination with Echo Sounder(E/S) for the coastal mapping. Apart from this purpose, the accuracy of ambiguity resolution with the OTF(On the Fly) method was tested with respect to the initialization time. The result shows that the accuracy is better than 1cm with 5-minute initialization in the distance of 10km baseline. The seaside topography was measured by the RTK GPS only, on the other hand the seafloor topography was surveyed in combination of RTK GPS and E/S. Comparing to the volume of seaside measured by RTK GPS and digital topographical map, the difference of only 2 % was achieved. This indicates that the coastal mapping with RTK GPS is successfully conducted. In addition it is also demonstrated that the 3-dimensional perspective model resulted from the undersea topography measured by RTK GPS and E/S is very close to that from the digital map. Through this study, it was verified that RTK GPS is to be very useful method in the analysis of coastal morphology owing to its capability of getting the precise DTM for the using of harbor reclamation, dredging, and the estimation of soil movement in a river.

• Korean Journal of Environmental Agriculture
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• v.24 no.1
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• pp.29-33
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• 2005

To develop proper soil management practices for reducing soil erosion, experiments were carried out by using lysimeters in Pyeongchang highland, Korea. Lysimeters installed at Hoenggye bad 13% slope, 15 m slope length and 3 m width. Lysimeters with 23% slope, 15 m slope length and 3 m width were also installed at Yongsan. Soil textures in Hoenggye and Yongsan lysimeter plots were silty clay loam and sandy loam, respectively. In the lysimeters potato was cultivated, and slant furrow culture and contour culture were applied. Up-down furrow and continuous fallow lysimeter was included in the experiments as a control plot. For the slant furrow and contour culture methods, minimum furrow mulching and gravel barrier were placed at each end of the furrows in the lysimeters from April to October in 2000 and 2001 to prevent soil and nutrient losses. In Heonggye, in two years experiments, average soil loss of 17 Mg/ha was found in the up-down and continuous fallow lysimeter and 2.6 Mg/ha from furrow minimum straw and slant furrow treatment, and 1.8 Mg/ha from slant furrow and gravel bag treatment. In the contour culture, the soil losses were further reduced. In Yongsan, soil loss in the slant furrow culture without any protection treatment was 167 Mg/ha, and the soil loss was reduce to 61 and 86 Mg/ha with minimum straw and gravel bag treatments, respectively. The soil loss could be reduced more than 45% by furrow minimum straw and gravel barrier. The furrow minimum straw or gravel bag barrier successfully reduced soil loss in clay loam soil in Heonggye, but still the treatments were not enough to reduce soil loss in saprolite piled sandy loam soil in Yongsan.

• Journal of Korea Multimedia Society
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• v.12 no.7
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• pp.929-940
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• 2009

This paper presents multipurpose watermarking scheme in coutourlet transform domain for copyright protection, authentication and transform detection. Since contourlet transform can detect more multi direction edge and smooth contour than wavelet transform, the proposed scheme embeds multi watermarks in contourlet domain based on 4-level Laplacian pyramid and 2-level directional filter bank. In the first stage of the robust watermarking scheme for copyright protection, we generates the sequence of circle patterns according to watermark bits and projects these patterns into the average of magnitude coefficients of high frequency directional subbands. Then the watermark bit is embedded into variance distribution of the projected magnitude coefficients. In the second stage that is the semi-fragile watermarking scheme for authentication and transform detection, we embed the binary watermark image in the low frequency subband of higher level by using adaptive quantization modulation scheme. From the evaluation experiment using Checkmark 2.1, we verified that the proposed scheme is superior to the conventional scheme in a view of the robustness and the invisibility.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.4
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• pp.534-538
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• 2011

One of the problems for cultivating crops in the mountainous highland is soil erosion and nutrients runoff. Alternative cropping ways were searched to reduce soil erosion and to ensure farm income in the mountainous highland agricultural region. Three edible wild plants including goatsbeard, Korean thistle, and aster, were selected to test as alternative crops to reduce soil erosion in mountain agriculture of highland area. In the first year, the soil losses from the alternative cropping were 26 to 63 percents of the soil loss from summer radish cultivated by conservation tillage with contour and plastic film mulching. The relative soil losses in the second year ranged from 2.8 to 5.5 percents in comparison with radish cultivation. Rapid surface coverage contributed to successive soil loss protection by these alternative crops. Farm net profit of these crops was greater than that of radish. Monitoring of yields of Korean thistle or aster for further experiments, however, might be necessary for economic cultivation due to yield reduction caused by consecutive production.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.13 no.2
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• pp.144-152
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• 1991

Various muscular flaps are used in oral and maxillofacial reconstructive surgery for the defects caused by tumor resection and trauma or for the correction of head and neck deformities. The sternocleidomastoid(SCM) muscle may be widely used as a muscular or myocutaneous flap in these lesion. The authors used SCM muscular flap for the expected parotid defect following benign tumor related conservative parotidectomy in three cases. We expected that prevention of post-operative facial deformity, reduction of dead-space and protection of denuded facial nerve etc. is lead by SCM muscular flap. But the total SCM flap can lead to some complications such as "flat neck deformity", limitation of neck movement and overcontouring of parotid defect. Therefore, the authors used split pedicled SCM muscular flap and it lead good favorable results of post-operative functional and esthetic problems.

• The Journal of the Korea Contents Association
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• v.11 no.11
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• pp.492-502
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• 2011

20 fossil sites of numerous fossil sites in Korea have been designated as Natural Monument for protection and conservation. Many of the sites which is located at the coastal area have been gradually disfigured by natural weathering, erosion and human activity. Thus the conservation of the original form and the documentation for the original figure are necessary. In this study, we applied 3D digital documentation to Natural Monument No. 394, Haenam Uhangri dinosaur, pterosaur, and bird footprint fossil site, for maintaining the original form of the dinosaur footprints. We were able to obtain the 3D digital data on two dinosaur footprint sites, a high resolution distributional map, and more accurate digital data of the dinosaur footprints applied the rendering method by ambient occlusion. 3D digital data on the dinosaur footprints is worth for the conservation and research data, moreover content for applying to the various fields such as to make 3D brochure, interactive contents, and so on.

• The Research Journal of the Costume Culture
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• v.18 no.2
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• pp.277-289
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• 2010

The objective of this study is to develop naturalistic knit designs inspired by Yann Arthus-Bertrand's works. For this purpose, we examined the present style of naturalism and history of naturalism though literature research, and then developed designs. The results are as follows: First, as scientific realism originated from a philosophical concept was adopted in literature and other genres, its meanings have been altered and comprehensively expanded according to the genres of which the term is being used. Naturalism of the modern times carries strong message of ecology and environmental protection. Second, the modern naturalism in fashion is manifested in expressing the image of nature and plasticity, instead of a mere use of the natural materials. As the aspects of ecology become more significant, elements of retro, recycle, or grunge are additionally integrated in fashion. Third, Naturalism expressed in knitwear is similar with that of other clothing in terms of color and textile, however, silhouette in knitwear is unique in its general naturalness and flowing effects. Embroidery, knitting of Jacquard and Intarsia, or crochet is used to express forms of objects from nature. Visual effects regardless of the contents of yarn, and pattern effects after knitting by using yarn, have influences on the material. Forth, the eight knit designs in expressing naturalism presented in this study took a motif from the works of Yann Arthus-Bertrand. They were created by rendering rhythm of the landscape with emphasis on brown color. Contour and surface touch were expressed through yarn and the structure of knit.

• Progress in Medical Physics
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• v.19 no.4
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• pp.276-284
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• 2008

A computed tomography (CT) is a powerful system for the effectively fast and accurate diagnosis. The CT system, therefore, has used substantially and developed for improving the performance over the past decade, resulting in growing concerns over the radiation dose from the CT. Advanced CT techniques, such as a multidetector row CT scanner and dual energy or dual source CT, have led to new clinical applications that could result in further increases of radiation does for both patients and workers. The objective of this study was to review the international guidelines of the shielding requirements for a CT facility required for a new installation or when modifying an existing one. We used Google Search Engine to search the following keywords: computed tomography, CT regulation or shield or protection, dual energy or dual source CT, multidetector CT, CT radiation protection, and regulatory or legislation or regulation CT. In addition, we searched some special websites, that were provided for sources of radiation protection, shielding, and regulation, RSNA, AAPM, FDA, NIH, RCR, ICRP, IRPA, ICRP, IAEA, WHO (See in Table 1 for full explanations of the abbreviations). We finally summarized results of the investigated materials for each country. The shielding requirement of the CT room design was very well documented in the countries of Canada, United States of America, and United Kingdom. The wall thickness of the CT room could be obtained by the iso-exposure contour or the point source method. Most of documents provided by international organizations were explained in importance of radiation reduction in patients and workers. However, there were no directly-related documents of shielding and patient exposure dose for the dual energy CT system. Based international guidelines, the guideline of the CT room shielding and radiation reduction in patients and workers should be specified for all kinds of CT systems, included in the dual energy CT. We proposed some possible strategies in this paper.

• Journal of Radiation Protection and Research
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• v.38 no.4
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• pp.208-213
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• 2013

The suitability of the site criteria is a basic requirement for securing safety of nuclear power plants. The suitability should be confirmed through the estimation of environmental radiation effects at the exclusion area boundary under the severe weather conditions. In this study, field tracer experiments over short range of 1 km radius under severe weather conditions were conducted at flat area in Daejeon. Severe weather conditions are represented with stable atmospheric condition and low wind speed. In general, the condition is appeared at clean night time with weak wind. The analysis of the measured distribution of the released tracer gas shows two big differences between the results of the past experiments conducted under the favorable weather conditions. One is the difficulty of finding the typical distribution of the released tracer gas with peak concentration in the downwind direction. The other one is the appearance of the contour of the concentration of tracer gas at several hundred meters even though the gas released at 10 m height over the ground.

• Journal of the Korean Geotechnical Society
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• v.30 no.6
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• pp.51-59
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• 2014

Shallow landslides and debris flows are a common form of soil slope instability in South Korea. These events may be generally initiated as a result of intense rainfall or lengthening rainfall duration because of the effects of climate change. This paper presents the evaluation of rainfall-induced natural soil slope stability and reinforced soil slope instability under vertical load (railway or highway load) throughout South Korea based on quantitative analysis obtained from 58 sites rainfall observatories for 38 years. The slope stability was performed for infinite and geogrid-reinforced soil slopes by taking an average of maximum rainfall every ten years from 1973 to 2010. Seepage analysis is carried out on unsaturated soil slope using the maximum rainfall at each site, and then the factor of safety was calculated by coupled analysis using saturated and unsaturated strength parameters. The contour map of South Korea shows four stages in 10-year-time for the degree of landslide hazard. The safety factor map based on long term observational data will help prevent rainfall-induced soil slope instability for appropriate design of geotechnical structures regarding disaster protection.