• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.35 no.3
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• pp.301-311
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• 1999

The investigation to evaluate the possible effects of fish behaviour on acoustic target strength was carried out during the 1997 and 1998 hydroacoustic-demersal trawl surveys in the southern waters of Korea.The swimming speed and the target strength of individual, acoustically resolved fished swimming through the sound beam were measured using the split-beam tracking method on board R/V Kaya.The results obtained can be summarized as follows:1. The alongship and athwartship angles between -3dB poionts of a hull mounted 38 kHz split beam tranducer used in these surveys was >$3.76^{\circ}\;and\;6.74^{\circ}$ respectively, and the equal energy contour obtained from the measured beam pattern showed approximately the circular pattern. 2. The swimming speed measured off the south coast of Sorido in 23 January 1997 ranged 0.10 to 0.80 m/s with the average swimming spped of 0.36 m/s, and the target strength ranged -64.8 to -31.7 dB with the average target strength of -52.7 dB. The most dominant species sampled in this survey area were Japanese scaled sardine, Sardinella zunasi and Konoshiro gizzard shad, Konosirus punctatus, respectively.3. The swimming speed measured off the east coast of Kojedo in 24 March 1997 ranged 0.10 to 1.10 m/s with the average swimming speed of 0.40 m/s, and the target strength ranged -64.8 to -51.5 dB with the average target strength of -59.2 dB. The most dominant species sampled in this survey area were Swordtip squid, Photololigo edulis, Konoshiro gizzard shad and Japanese flying squid, Toddarodes pacificus, respectively and the swimming activity of these species seems to be controlled at speeds between 0.20 and 0.60 m/s. 4. The swimming speed measured the south coast of Kojedo in 25 March 1997 ranged 0.10 to 1.40 m/s with the average swimming speed of 0.51 m/s and the target strength ranged -64.3 to -47.7 dB with the average target strength of -55.1 dB. The most dominant species sampled in this survey area were Swordtip squid, Blotchy sillage, Sillago maculata and japanese scaled sardine, respectively and the swimming activity of these species seems to be controlled at speeds between 0.20 and 0.70 m/s.5. The swimming speed measured during morning twilight in the southeastern water of Cheju Island in 11 July 1998 ranged 0.20 to 1.0 m/s with the average swimming speed of 0.53 m/s, and the target strength ranged -65.0 to -47.0 dB with the average target strength of -57.1 dB. The most dominant species sampled in this survey area were Swordtip squid, Black scraper, Thamnaconus modesutus and japanese flying squid, respectively and the tile angle ranged$ +28^{\circ}\;to\;+2^{\circ}$ with the average tilt angle of -8.1$^{\circ}$ showing the downward migration.

• The Journal of Fisheries Business Administration
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• v.44 no.1
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• pp.71-79
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• 2013

This study is aimed to estimate market integration of wild caught fish species on the Korean market, using both multivariate and bivariate cointegration analysis. For the analysis of market integration between wild caught fish species, major four fish species those are most popular fish in the market and caught by the large purse seine fishery-chub mackerel, jack mackerel, hairtail and spanish mackerel-were selected as analytical target fish species. And their real monthly price data from January 2000 to December 2011 were used in the analysis. The results of the multivariate cointegration test for four wild caught fish species showed that there would be long-term equilibrium relationships among prices of four wild caught fish species, and consequently, the markets for wild caught fish species were estimated to be integrated. The results of exclusion test and bivariate cointegration test also supported that there would be a clear evidence to suggest that all target wild caught fish species were cointegrated each other.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.5
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• pp.38-50
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• 2010

Expressways are often upgraded by widening the lanes and/or by reshaping the roads to be more linear for faster travel time. However, during the process of improving the route of the expressways, the areas where the old expressways used to be are often unused and abandoned. When these neglected sites are left alone, they often become dump sites causing pollution and impacting the surrounding environment. Therefore, it is important to restore the abandoned expressway sites to its full natural beauty. In this study, the abandoned expressway at the Soksa interchange in Pyungchang county, located in Kangwon province was studied for establishing the model of ecological restoration project. Considering the characteristics of the site, the target flora species was chosen to be Quercus species and the target fauna species as amphibians. After the target species were carefully chosen, each species' habitat requirements were studied in order to figure out the appropriate methods toward habitat restoration specifically for these species. In addition, to determine the most efficient method toward restoration of abandoned expressways, the study utilized the planting hole techniques, the crack techniques, and the colonization techniques. In terms of the spatial organization, public education program is incorporated at the main entrance area and the programs for experimenting, and developing vegetation and habitat restoration techniques are placed in the vicinity. In the master plan-to provide natural ecosystem at the site-ASCON (asphalt concrete) was removed first, then plans for restoration including species' habitat restoration were established. Furthermore, the project included plans for improving water quality polluted through non-point source considering the surrounding nearby road and farm lands. Finally, the study established a planning process that will experimentally apply to the abandoned expressway restoration method. In the future, there will be a continuous monitoring of the methods applied to verify if the restoration methods are effective. Also, new restoration techniques should be available according to a variety of abandoned expressways' characteristics.

• Journal of Korean Society on Water Environment
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• v.27 no.6
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• pp.822-829
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• 2011

The purpose of the present study is to estimate the ecological instream flow for conservation and restoration of fish habitat in running water ecosystem which has very important status for stream environment. Estimation of the ecological instream flow in the present study was carried out by application of a two-dimensional depth averaged model of river hydrodynamics, River2D model. It can model fish habitat in natural streams and rivers and assess the quality of physical habitat accoriding to the species preferences for habitat suitability. Zacco platypus and Zacco temmincki were selected as target fish species in the study area of the Seomjin river. The Habitat Suitability Criteria (HSC) developed by Sung et al. (2005) were used for target fish species, life stages and habitat conditions in the study. Weighted usable area (WUA) was computed by the River2D model considering preferences of target fish species for velocity, depth, and channel substrate. The result revealed that the ecological instream flow of $10.0m^3/s$ is needed to maintain the target fish habitat at each life stage in the river.

• Korean Journal of Veterinary Research
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• v.39 no.3
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• pp.513-522
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• 1999

DNA hybridization assay using probes prepared from liver was carried out to identify species characterization of the domestic animals. Gel electrophoresis showed that the target DNA extracted from raw muscle were 1kb and uniform pattern while fragments size of heated muscle were irregular. Hybridization was performed by adding 200ng/ml probe in hybridization solution and incubating for 12 hours at $68^{\circ}C$. To obtain good discrimination, applied washing buffer and washing step differently depending on the species. The probes of pig, horse and dog formed the specific hybrids with each target DNA respectively. Although cross reaction was detected in cattle, goat and sheep but signal intensity among these species made the discrimination possible each other. Such pattern was the same in the cases of chicken, turkey and duck. The hybridization pattern of heated muscle was similar to that of raw muscle in general, but the signal intensity was inferior to that of raw muscle. Species identification between closely related animal species, hybridized using the target DNA of such closely related animal species as a blocking agent, remarkable increase of discrimination from the evident decrease of non specific reaction compared with the control group. In addition, in the admixture where certain meat was included in the beef, pork, chicken meat, we could find whether any unjust meat was admixed or not. In this case, detection limit of certain meat in admixture was 1%.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.44 no.1
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• pp.37-45
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• 2008

Assessment and management of fisheries abundance in fresh water like a river or a lake is very important to maintain fisheries itself as well as tourist industry even if their scale is not much large. The species for catch in fresh water are mainly a mandarin fish, a carp, an eel, and others. Because oriental river prawn is a main prey of these species and the change in its abundance is directly related to their abundance change in fresh water, information on the abundance and distribution of the species are necessary. Hydroacoustic survey is known to one of the efficient method among several methodology. Information on acoustic target strength is key parameter to estimate abundance for acoustic survey. In this study, measurements on oriental river prawn, Macrobrachium koreana, were conducted for two high frequencies(200kHz and 420kHz) with tilt angle using automatic rotating system. The results of acoustic target strength obtained from the experiment were compared with those of acoustic scattering model, Distorted Wave Born Approximation(DWBA) model. For 200kHz, the result of acoustic target strength experiments was expressed in terms of the averaged target strength dependence on the body langth(BL, cm) as a following relationship; < $TS_{200kHz}$ > = 45.9log(BL) - 107.4. These results provide basic information for studying acoustic target strength and conducting acoustic survey of oriental river prawn.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.27 no.2
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• pp.67-90
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• 2024

The purpose of this study is to present the ecological data for conservation and management of three wetlands by surveying the vascular plants in Ganam reservoir, Ahnshim wetland and Jeomsae swamp. The whole taxa of vascular plants were 376 taxa including 90 families, 252 genera, 341 species, 7 subspecies, 24 varieties, 2 forms, 1 hybrid and 1 cultivar, and the planted species were 66 taxa including Ginkgo biloba and so on. The rare plants were 7 taxa including Euryale ferox(VU), Aristolochia contorta(LC), Koelreuteria paniculata(VU), Sagittaria trifolia(DD), Hydrocharis dubia(LC), Ottelia alismoides(LC) and Sparganium stoloniferum(VU). The Korean endemic plant was 1 taxon of Lespedeza maritima. In total, there were 21 taxa of floristic target species including 1 taxon of garde V, 2 taxa of grade IV, 6 taxa of grade III, 5 taxa of grade II and 7 taxa of grade I . The hydrophytes were 51 taxa including 36 taxa of emergent species, each 6 taxa of floating-leaved and submerged species and 3 taxa of free-floating species. The invasive alien plants were 79 taxa including 75 taxa of naturalized plants and 4 taxa of casual alien plant. The ecosystem disturbing species 6 taxa including Sicyos angulatus, Ambrosia artemisiifolia, Lactuca seriola, Symphyotrichum pilosum, Paspalum distichum and Humulus scandens.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.2
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• pp.124-137
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• 2010

This study was started with the objective of restoring abandoned embanked farms, which are recently increasing, to mud flat by putting in least amount of energy in the aspect of environmental restoration. For the direction and establishment of the proposal for the restoration of mud flat using embanked farms, a case of Maipo Wetland in Hongkong was analyzed, and a proposal was prepared considering the condition of mud flat in Gochang. The restoration of mud flat in Gochang is intended to create various wetland ecological spaces as well as to provide opportunities for experience, education, recreation, and tourism. Effort was made to development an environment closest to the local ecological environment considering the shape and topographical condition of existing abandoned farms. For construction of the habitat, a target species was chosen and the plan for selection, planting, and management of species of trees suitable for the target species was established. In addition, the water level will be controlled by water gates to conform to the resting, spawning, breeding, and migration period considering the behavioral pattern of waders, the target species. The research on the restoration of mud flat in Korea is in incipient stage and this study provided an opportunity to review the possibility of restoration of abandoned embanked farms to mud flat. For the success of mud flat restoration from a long-term perspective, development of acclimating design infrastructure, technology improvement for mud flat restoration, and basis of partnership for the maintenance should be prepared in a systematical way.

• Journal of Ecology and Environment
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• v.38 no.2
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• pp.163-173
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• 2015

The occurrence of wild boars (Sus scrofa Linnaeus) and reports of wildlife-vehicle conflicts (i.e., road-kill) involving them have increased in natural forest regions of Korea. In the past few decades, many wildlife passages have been constructed to reduce vehicle collisions involving wildlife species. However, few studies have assessed the habitat suitability of target wildlife species when locating the construction sites of wildlife passages. Target species rarely use wildlife passages if built in an inappropriate location. Therefore, a quantitative habitat model is required to find suitable sites for wildlife passages that can connect the fragmented forest patches of wildlife habitats in Korea. In this study, the wild boar was selected as the target species, and six environmental variables (percentage of Quercus forest, slope aspect, distance to roads, water accessibility, forest stand age and density) were measured. The habitat model for wild boars was developed with a Delphi survey, and habitat suitability maps were delineated for the provinces of Gangwon-do and Jeollanam-do. In this study, 298 and 64 boars were observed in Gangwon-do and Jeollanam-do, respectively. Observations of wild boars derived from the second nationwide natural environmental survey were used to evaluate the habitat model. Habitat suitability maps that superimposed existing road networks suggested that wild boar habitats were severely fragmented in both provinces, particularly in Gangwon-do. To connect the fragmented habitats and prevent wildlife-vehicle collisions, this study proposes 11 and 5 wildlife passage sites in Gangwon-do and Jeollanam-do, respectively.

• Journal of the Korean Institute of Landscape Architecture
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• v.34 no.1 s.114
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• pp.10-20
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• 2006

This study is to introduce the improvement and management of Ecoduct located in Uiwang's Mt. Obong, Gyeonggi province. The inner planting of Ecoduct is not very related to the flora of mountain areas nearby. The difference in the index of plant crown volume(GVZ), the similarity index(S.I.), and monitored animals is significant between Ecoduct and mountain areas. Putting together all of the results, the initial selection of movement and target species is excessive in number. Target species must be selected again. They will be species that are currently found on the site. The Ecoduct space must be divided into two parts: buffer planting space and wildlife corridor. Reforestation is needed since the GVZ is remarkably lower in Ecoduct than in the nearby mountain areas. Besides the vegetation of Ecoduct is densely planted in guidance planting space to connect the southern Quercus mongolica community and the northern Quercus acutissima community. Proper upkeep after construction should be continuously conducted to maintain the procedure of natural change.