• Economic and Environmental Geology
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• v.53 no.6
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• pp.729-742
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• 2020

In this study, we analyze seabottom conditions and characteristics integrated with topographic data, seafloor mosaic, underwater images and orthophoto(drone) of soft-hard bottom area around the Sib-Ri rock in the northern shore of the East Sea(Gyeongpo Beach, Gangneung). We obtained field survey data around the Sib-Ri rock(about 600 m × 600 m). The Sib-Ri rock is formed by two exposed rocks and surrounding reef. The artificial reef zone made by about 200 ~ 300 structures is shown the western area of the Sib-Ri rock. The underwater rock region is extended from the southwestern area of the exposed the Sib-Ri rock with 9 ~ 11 m depth range. The most broad rocky seabottom area is located in the southwestren area of the Sib-Ri rock with 10 ~ 13 m depth range. The study area were classified into 4 types of seabottom environment based on the analysis of bathymetric data, seafloor mosaics, composition of sediments and images(underwater and drone). The underwater rock zones(Type I) are the most distributed area around the Sib-Ri Rock(about 600 m × 600 m). The soft seabottom area made by sediments layer showed 2 types(Type II: gS(gravelly Sand), Type III: S(Sand)) in the areas between underwater rock zones and western part of the Sib-Ri rock(toward Gyeongpo Beach). The artificial reef zone with a lot of structures is located in the western part of the Sib-Ri rock. Marine algae(about 6 species), Phylum porifera(about 2 species), Phylum echinodermata(about 3 species), Phylum mollusca(about 3 species) and Phylum chordata(about 2 species) are dominant faunal group of underwater image analysis area(about 10 m × 10 m) in the northwestern part of the Sib-Ri rock. The habitat of Phylym mollusca(Lottia dorsuosa, Septifer virgatus) and Phylum arthropoda(Pollicipes mitella, Chthamalus challengeri hoek) appears in the intertidal zone of the Sib-Ri rock. And it is possible to estimate the range and distribution of the habitat based on the integrated study of orthphoto(drone) and bathymetry data. The integrated visualization and mapping techniques using seafloor mosaic images, sediments analysis, underwater images, orthophoto(drone) and topographic data can provide and contribute to figure out the seabottom conditions and characteristics in the shore of the East Sea.

• Journal of the Korean Association of Geographic Information Studies
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• v.25 no.1
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• pp.28-43
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• 2022

This study classified UAV image-based physical spatial types for parks in urban areas of Changwon City and analyzed thermal comfort characteristics according to physical spatial types by comparing them with ENVI-met thermal comfort results. Physical spatial types were classified into four types according to UAV-based NDVI and SVF characteristics. As a result of ENVI-met thermal comfort, the T_MRT difference between the tree-dense area and other areas was up to 30℃ or more, and it was 19. 6℃ at 16:00, which was the largest during the afternoon. As a result of analyzing UAV-based physical spatial types and thermal comfort characteristics by time period, it was confirmed that the physical spatial types with high NDVI and high SVF showed a similar to thermal comfort change patterns by time when using UAV, and the physical spatial types with dense trees and artificial structures showed a low correlation to thermal comfort change patterns by time when using UAV. In conclusion, the possibility of identifying the distribution of thermal comfort based on UAV images was confirmed for the spatial type consisting of open and vegetation, and the area adjacent to the trees was found to be more thermally pleasant than the open area. Therefore, in the urban planning stage, it is necessary to create an open space in consideration of natural covering materials such as grass and trees, and when using artificial covering materials, it is judged that spatial planning should be done considering the proximity to trees and buildings. In the future, it is judged that it will be possible to quickly and accurately identify urban climate phenomena and establish urban planning considering thermal comfort through ground LIDAR and In-situ measurement-based UAV image correction.

• Journal of Intelligence and Information Systems
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• v.29 no.3
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• pp.185-209
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• 2023

With the advent of the 4th industrial revolution, various technologies have received much attention. Technologies related to the 4th industry include the Internet of Things (IoT), big data, artificial intelligence, virtual reality (VR), 3D printers, and robotics, and these technologies are often converged. In particular, the robotics field is combined with technologies such as big data, artificial intelligence, VR, and digital twins. Accordingly, much research using robotics is being conducted, which is applied to distribution, airports, hotels, restaurants, and transportation fields. In the given situation, research on human-robot interaction is attracting attention, but it has not yet reached the level of user satisfaction. However, research on robots capable of perfect communication is steadily being conducted, and it is expected that it will be able to replace human emotional labor. Therefore, it is necessary to discuss whether the current human-robot interaction technology can be applied to business. To this end, this study first examines the trend of human-robot interaction technology. Second, we compare LDA (Latent Dirichlet Allocation) topic modeling and BERTopic topic modeling methods. As a result, we found that the concept of human-robot interaction and basic interaction was discussed in the studies from 1992 to 2002. From 2003 to 2012, many studies on social expression were conducted, and studies related to judgment such as face detection and recognition were conducted. In the studies from 2013 to 2022, service topics such as elderly nursing, education, and autism treatment appeared, and research on social expression continued. However, it seems that it has not yet reached the level that can be applied to business. As a result of comparing LDA (Latent Dirichlet Allocation) topic modeling and the BERTopic topic modeling method, it was confirmed that BERTopic is a superior method to LDA.

• Journal of the Korean Society for Marine Environment & Energy
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• v.9 no.1
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• pp.1-13
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• 2006

A field survey on the spatio-temporal distribution characteristics and origins of organic matter in surface sediments was carried out monthly at six stations in Gamak Bay, South Korea from April 2000 to March 2002. The range of ignition loss(IL) was $4.6{\sim}11.6%(7.1{\pm}1.6%)$, while chemical oxygen demand(CODs) ranged from $12.25{\sim}99.26mgO_2/g-dry(30.98{\pm}19.09mgO_2/g-dry)$, acid volatile sulfide(AVS) went from no detection(ND)${\sim}10.29mgS/g-dry(1.02{\pm}0.58mgS/g-dry)$, and phaeopigment was $6.84{\sim}116.18{\mu}g/g-dry(23.72{\pm}21.16{\mu}g/g-dry)$. The ranges of particulate organic carbon(POC) and particulate organic nitrogen(PON) were $5.45{\sim}23.24 mgC/g-dty(10.34{\pm}4.40C\;mgC/g-dry)$ and $0.71{\sim}2.99mgN/g-dry(1.37{\pm}0.58mgN/g-dry)$, respectively. Water content was in the range of $43.1{\sim}77.6%(55.8{\pm}5.6%)$, and mud content(silt+clay) was higher than 95% at all stations. The spatial distribution of organic matter in surface sediments was greatly divided between the northwestern, central and eastern areas, southern entrance area from the distribution characteristic of their organic matters. The concentrations of almost all items were greater at the northwestern and southern entrance area than at the other areas in Gamak Bay. In particular, sedimentary pollution was very serious at the northwestern area, because the area had an excessive supply of organic matter due to aquaculture activity and the inflow of sewage from the land. These materials stayed longer because of the topographical characteristics of such as basin and the anoxic conditions in the bottom seawater environment caused by thermocline in the summer. The tendency of temporal change was most prominently in the period of high-water temperatures than low-water ones at the northwestern and southern entrance areas. On the other hand, the central and eastern areas did not show a regular trend for changing the concentrations of each item but mainly showed a higher tendency during the low-water temperatures. This was observed for all but AVS concentrations which were higher during the period of high-water temperature at all stations. Especially, the central and eastern areas showed a large temporal increase of AVS concentration during those periods of high-water temperature where the concentration of CODs was in excess of $20mgO_2/g-dry$. The results show that the organic matters in surface sediments in Gamak Bay actually originated from autochthonous organic matters with eight or less in average C/N ratio including the organic matters generated by the use of ocean, rather than terrigenous organic matters. However, the formation of autochthonous organic matter was mainly derived from detritus than living phytoplankton, indicated the results of the POC/phaeopigment ratio. In addition, the CODs/IL ratio results demonstrate that the detritus was the product of artificial activities such as dregs feeding and fecal pellets of farm organisms caused by aquaculture activities rather than the dynamic of natural ocean activities.

• Journal of the Korea Concrete Institute
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• v.21 no.2
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• pp.187-197
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• 2009

This paper presents a systematic approach for estimating fragility curves and damage probability matrices for different frequencies. Fragility curves and damage probability indicate the probabilities that a structure will sustain different degrees of damage at different ground motion levels. The seismic damages are to achieved by probabilistic evaluation because of uncertainty of earthquakes. In contrast to previous approaches, this paper presents a method that is based on nonlinear dynamic analysis of the structure using empirical data. This paper presents the probability of damage as a function of peak ground acceleration and estimates the probability of five damage levels for prestressed concrete (PSC) bridge pier subjected to given ground acceleration. At each level, 100 artificial earthquake motions were generated in terms of soil conditions, and nonlinear time domain analyses was performed for the damage states of PSC bridge pier structures. These damage states are described by displacement ductility resulting from seismic performance based on existing research results. Using the damage states and ground motion parameters, five fragility curves for PSC bridge pier with five types of dominant frequencies were constructed assuming a log-normal distribution. The effect of dominant frequences was found to be significant on fragility curves.

• Cartoon and Animation Studies
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• s.15
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• pp.221-235
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• 2009

Most of the sounds used in animated films are artificially made. A large number of the sounds used are either actual sound recordings or diversely processed artificial sounds made with professional sound equipments such as synthesizers. One animation episode contains numerous amounts of sounds, resulting in significant sound production costs. These sounds have full potential to be reused in different films or animations, but in reality we fail to do so. This thesis discusses ways these sound sources can be acknowledged as added new values to the present market situation as a usable 'digital content'. The iTunes Music Store is an American Apple company product that is acknowledged as the most successful digital content distribution model at the time being. Its system's sound library has potential for application in the Korean sound industry. In result, this system allows the sound creator to connect directly to the online store and become the initiative content supplier. At the same time, the user can receive a needed content easily at a low price. The most important part in the construction of this system is the search engine, which allows users to search for data in short periods of time. The search engine will have to be made in a new manner that takes into consideration the characteristics of the Korean language. This thesis presents a device incorporating the Wiki System to allow users to search and build their own data bases to share with other users. Using this system as a base, the Korean animation sound library will provide development and growth in the sound source industry as a new digital sound content.

• Journal of the Korean association of regional geographers
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• v.9 no.2
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• pp.203-216
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• 2003

The process of constructing coastal digital elevation model(DEM), for the 3 dimensional analysis, is composed by abstracting land layers for land elevation and water depth, reprojecting UTM, relocating geographical grid, and interpolating works. The geomorphic set of shallow sea, including tidal current, tidal zone deposition, and water depth distribution, was analyzed by eye search of Landsat TM image, masking of land zone, band combination and regression analysis. Some horizontal differences, between combined DEM and surveyed data of shallow sea, was corrected for analysis. Analyzed geomorphic elements are stream channel, alluvial fan, coastal terrace, tidal current. and shallow sea bank. Results of analysis present that transported fluvial materials influence tidal sedimentation, especially from Gahwacheon river, for the role of artificial draining flooding waters from Jinyang Reservoir, almost in the summer season. In the coastal area with less tidal current, more fine materials are deposited. The influence of currental deposition are higher on small pockets with west coast of well developed terraces. The lower skirt of alluvial fans developed into the tidal zone of shallow sea. Small pocket type bays are closed by coastal current, and less influenced from tidal deposition. The bank of Jinju Bay are developed originally from submerging of remnant erosional mountain ranges, and play on the role of trapping fine materials.

• Bulletin of the Korean Chemical Society
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• v.24 no.4
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• pp.446-452
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• 2003

Some new nanohybrid materials have been synthesized by intercalating the oxotitanium(IV) meso-tetrakis(4- sulfonatophenyl) porphyrin$(O=Ti^{(IV)} TSPP)$ into the Zn/Al layered double hydroxides (LDHs), and their structures and photophysical properties have been investigated by various laser spectroscopic techniques. According to the XRD pattern of the synthesized nanohybrid materials, the macrocycle plane of $O=Ti^{(IV)}$ TSPP are grafted perpendicular to the LDH layers. The $O=Ti^{(IV)}$ TSPP-intercalated LDH exhibits band broadening of the absorption spectrum and a blue shift of Q-band as compared to that observed in solution. Resonance Raman spectral measurements demonstrate that the positively charged LDHs give rise to a slight decrease of the electronic density of the porphyrin ring accompanying a small change of the electronic distribution of the $O=Ti^{(IV)}$ TSPP. Consequently the LDH environment affects the energies of the two highest occupied molecular orbitals (HOMOs) of the $O=Ti^{(IV)}$) TSPP, $a_{1u}$ and $a_{2u}$, producing a mixed orbital character. Being consistent with these electronic structural changes of $O=Ti^{(IV)}$ TSPP in LDH, both the fluorescence spectral change and the fsdiffuse reflectance transient measurements imply that the photoexcitation of the $O=Ti^{(IV)}$ TSPP intercalated into LDH undergoes fast relaxation to the O=Ti(IV) $TSPP^+-LDH^- $charge transfer (CT) state within a few picoseconds, followed by a photoinduced electron transfer between the O=Ti(IV) TSPP and LDHs with a rate constant greater than %1×10^{10}S^{-1}$. No evidence is found for back electron transfer. In conclusion, the $O=Ti^{(IV)}$ TSPP intercalated LDH seems to be a possible candidate for an artificial reaction center for an efficient solar energy conversion system.

• Korean Journal of Environment and Ecology
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• v.11 no.3
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• pp.334-351
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• 1997

To study restoration model of evergreen broad-leaved forests in warm temperate region, vegetation structure was studied at Wando(Island) as a case study. Quercus acuta was a dominant species at evergreen broad-leaved forests in Wando(Island). Majority of evergreen broad-leaved forests was a thirty years old coppice forest. Reforested vegetation and deciduous broad-leaved forests was developed at a mid-slope districts and a piedmont. Deciduous broad-leaved forestsconsisted of Quercus serrata, Carpinus tschonoskii, Carpinus coreana, etc., was developed at a ridge and higher districts. Evergreen broad-leaved woody plants were growing at a forest floor of deciduous broad-leaved forests. The species over sixty percent of constanty ratio in forty seven plots were Ligustrum japonicum, Trachelospermum asiaticum var. intermedium, Quercus acuta and Eury japonica. The vascular plants in the Wando(Island) was summarized as 488 taxa which composed as 101 families, 321 genus, 426 species, 56 varieties, 5 forms and 1 hyvrid. Evergreen broad-leaved woody stecies was 32 taxa which composed as 23 genus, 30 species and 2 varieties. The species such as Liliope platyphylla of Liliaceae and Pueraria thunbergii of Leguminosae, etc. was recorded as the highest values for their widely distribution in the areas. On the contrary, and forty taxa of plants such as Viburnum erosum of Caprifoliaceae, Traceholospermum asiaticum var. intermedium was recorded as over 50% of constancy ratio. Two hundred and nine taxa of plants such as Juglans manshurica of Juglandaceae, Cornus walteri of Cornaceae and Rodotypos scandens of Rosaceae, etc. was showed the specific trends due to long-term artificial disturbance. The forest of Pinus thunbergii showde the highest species diversities(155 species per 600m$^{2}$), while the Cinnamomum japonicum-Tracheolospermum asiaticum var. intermedium community showed the lowest species diversities(23 species per 600m$^{2}$).

• Journal of the Korean Association of Geographic Information Studies
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• v.8 no.2
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• pp.145-156
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• 2005

An artificial disturbance like forest fragmentation has affected the sustainability of forest ecosystem. Therefore, in order to manage the forest ecosystem efficiently needed to analyze quantity and quality (structural pattern) of forest simultaneously. This study analyzed the structural patterns of forest landscape to provide a basic data for evaluation and management of forest ecosystem in Nakdong River Basin during 10 years from 1980s to 1990s using landscape indices and GIS methods. Forest distribution maps and 6 landscape indices(LPI, PD, ED, MSI, CPLAND, IJI) for the analysis were reconstructed from land-cover maps constructed by Ministry of Environment and pearson correlation analysis. According to the structural analysis of forest landscape using landscape indices, the forest fragmentation of watersheds along the main stream of the Nakdong river was more severe than any other watersheds. Futhermore, the Nakong-sangju and Nakdong-miryang watersheds had unstable forest structures as well as least amount of forest quantity. Thus, these watersheds need significant amount of forest through a new forest management policy considering local environmental conditions. The connectivity between forests in local regions should be considered as well.