• The Korean Journal of Pesticide Science
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• v.2 no.2
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• pp.119-125
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• 1998

A nation-wide fact-finding survey was done to provide the basic information for establishing the rational weed control scheme in paddy rice. A total of 445 respondents including 273 farmers and 172 pesticide dealers was involved in this survey. Dominant weeds in rice paddy field were Echinochloa crus-galli, Eleocharis kuroguwai, Sagittaria pygmaea, Sagittaria trifolia, etc.. Preferred herbicides widely used by farmners were ranked in the following order; butachlor 5GR, pyrazosulfuron-ethyl + molinate 5.07GR, molinate + cinosulfuron 5.08GR, meanwhile, those recommended by pesticide dealers were; pyrazosulfuron-ethyl + molinate 5.07GR, molinate + cinosulfuron 5.08GR, and butachlor 5GR. The guidelines to choose the preferred herbicides was primarily based on the experience, which was occupied about 45%. Approximately 56% of the farmers followed the recommended herbicide dosage and 43% of them applied the herbicides before weed germination (pre-emergence treatment). In addition, most farmers applied herbicides at least two times with systematic application schedule. Application method of granular formulation was broadcasting by hand, while that of sprayable ones was by high-pressure sprayer. Some farmers answered that they had experienced phytotoxicity in the crop by applied herbicides, of which higher experience was observed from the farmers who applied by high-pressure sprayer. It was analyzed significantly that the feasible herbicides to cause phytotoxicity in rice at farmer's level were butachlor 5GR, esprocarb + pyrazosulfuron-ethyl 5.07GR and bensulfuron-methyl + molinate 5.17 GR.

• The Korean Journal of Pesticide Science
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• v.20 no.2
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• pp.133-137
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• 2016

In Korea, six mealybug species have been reported on pears. This study investigated the occurrence of mealybugs in 19 pear orchards from 2013 to 2014. Two species, Crisicoccus matsumotoi Siraiwa (Hemiptera: Pseudococcidae) and Pseudococcus comstocki Kuwana were mainly found. The dominant species was C. matsumotoi identified on 73% of infested fruit. Toxicities of 14 registered insecticides (Buprofezin+Acetamiprid EC, Buprofezin+Amitraz EC, Buprofezin+Clothianidin SC, Buprofezin+Dinotefuran WP, Buprofezin+Etofenprox WG, Buprofezin+Thiacloprid SC, Buprofezin+Thiamethoxam SC, Benfuracarb WG, Acetamiprid WP, Clothianidin SC, Dinotefuran WG, Thiacloprid SC, Thiamethoxam WG, Sulfoxaflor SC) commonly used to control P. comstocki were evaluated to C. matsumotoi nymphs and adults at the recommended concentration. As a results, all insecticides exhibited strong insecticidal activity with 100% mortality of both nymphs and adults. These results indicate that the 14 insecticides can be used in control for C. matsumotoi in field.

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.4
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• pp.419-428
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• 2020

The flow past a wall mounted square cylinder, a typical and basic shape of building, bridge or offshore structure, was simulated using URANS computation through adoption of three turbulence models, namely, the k-ε model, k-ω model, and the v²-f model. It is well known that this flow is naturally unstable due to the Karman vortex shedding and exhibits a complex flow structure in the wake region. The mean flow field including velocity profiles and the dominant frequency of flow oscillation that was from the simulations discussed earlier were compared with the experimental data observed by Wang et al. (2004; 2006). Based on these comparisons it was found that the v²-f model is most accurate for the URANS simulation; moreover, the k-ω model is also acceptable. However, the k-ε model was found to be unsuitable in this case. Therefore, v²-f model is proved to be an excellent choice for the analysis of flow with massive separation. Therefore, it is expected to be used in future by studies aiming to control the flow separation.

• Journal of architectural history
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• v.11 no.2 s.30
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• pp.7-22
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• 2002

Architectural style is said to be product reflecting political, social and cultural condition. Especially, in colony, architectural style is strongly related to political condition or policy. After colonization in 1910, public buildings with western historical architectural style in Japanese version were widely built by Japanese colonial government in Korea. And in the late 1920s, modernism style in architecture became dominant in Korea as like other countries. In this situation, curious buildings in strange architectural styles came out. One example is railroad station buildings with traditional Korean architectural style and timber house station having a steep roof which is widely used in North Europe such as Alps area with good sights and mountains. Generally, the colonizer says that colonization is the only way to save the colony at crisis defined by colonizer and they insist that they can help the colony modernize. To justify colonization, the colonizer attributes the colonization to the characteristics of the nation and stagnation of the traditional culture etc.. Accordingly, the colonizer tries to depreciate colony's traditional value and culture. In case of colony which has similar cultural background historically (in this case, economical exploitation is less important than other Asian colony by European power), this depreciation of traditional value and culture in Korea was done more strongly than others. At this time, we should understand special relation between Korea and Japan historically. Even though, colony's locality is adopted by the colonizer in public fields, which is based on political purpose or exotic taste etc.. In early days of Japanese ruling period, Japan never use the Korean traditional facts in public. Therefore there is no use of Korean traditional architectural style in public field. In late 1920s, some railroad station buildings were constructed in new styles without precedence in modern Korea. One is railroad station buildings in Korean traditional architectural style, the other is railroad station buildings in timber house stations having a steep roof which is different form western historical architectural style. It was mystery that Japan had constructed railroad stations in Korean traditional style which Japan had tried to destroy together with Western style railroad station buildings. This paper is made to solve the mystery why the colonizer(Japan) constructed entirely different types of railroad stations at the same time in the late 1920s and 1930s. The key point to solve this mystery is tourism. In this paper, to solve this mystery, I try to use terminology' 'Colonial Tourism' in architecture why colonial power had constructed railroad stations with colony's traditional architectural style and Western style having a steep roof which can be seen north European region.

• Journal of Korean Society of Forest Science
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• v.79 no.1
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• pp.33-41
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• 1990

The purpose of this study is to investigate the developmental process of plant community during the secondary succession through the analysis of floristic composition, life form etcectra in burned site, and the structure of forest stand before forest fire occurrence was estimated by the method of anatomical wood identification for dead trees in burned site, Cheisuk-bong in Mt. Chiri of Korea. Plant community before forest fire occurrence was estimated the high mountain conifer stand of the last successional stage to consist of Pinus koraiensis(75%), Abies koreana(15%) and Picea jezoensis(10%), and Betula costata was survived only one species after forest fire occurrence. The total number of plant species in the investigated area was 19 families and 23 species that was identified. The dominate species in burned site were Festuca ovina and Arrhenatherum elatius, Carex humilis, Ligularia fischeri etcectra in the investigated area flora. The life form of plant in burned site was the erect from 47.8%, the tufted from 30.4%, the branched and the prostrate from was both 8.7%, It was assumed that dominant species in the burned sites were Gramineae (Festuca ovina, Arrhenatherum elatius), Carex humilis ${\rightarrow}$Sorbus commixta, Rhododendron schrippenbachii, Sambucus williamsii var. coreana, Tripterygium regelii ${\rightarrow}$Acer pseudo-sieboldianum var. koreanum, Betula costata, Quercus mongolica${\rightarrow}$Pinaceae forest(Pinus koraiensis, Abies koreana, Picea jezoznsis).

• Journal of the Korean earth science society
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• v.34 no.1
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• pp.59-68
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• 2013

Focal mechanism solutions in the southwestern region of the Korean Peninsula ($34^{\circ}N-36^{\circ}N$, $126^{\circ}E-128^{\circ}E$) were obtained from the analysis of the recent 22 earthquakes ($M{\geq}2.0$) occurred from January, 2005 to March, 2011. The spatial differences between the epicenters recalculated by this study and those by KMA (Korea Meteorological Administration) and KIGAM (Korea Institute of Geoscience and Mineral Resources) are less than $0.05^{\circ}$, indicating a small deviation. However, they become a little bit larger in the coastal area due to a biased arrangement of seismic stations. Redetermined depths of hypocenters show a difference less than 12.7 km by comparison with the depth data announced by KIGAM. Most epicenters in inland area are located closely to the lineaments. Fault plane solutions were obtained from the analysis of P and SH wave polarities, and SH/P amplitude ratios. They show strike-slip faulting or strike-slip faulting with reverse components dominantly. The P-axes trends are mainly ENE-WSW or E-W directions. The direction of fault plane and auxiliary plane with 'NNE-SSW and WNW-ESE' or 'NE-SW and NW-SE' are dominant and almost parallel to the general trends of lineaments in the study area.

• ALGAE
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• v.23 no.2
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• pp.135-140
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• 2008

A field survey for dinoflagellate cysts was carried out from May 2000 to November 2002 for the Southwest Sea of Korea. A total dinoflagellate cysts identified were 33 species, which belonged to 17 genera, 31 species, and 2 unidentified species. A cysts density were 16-1,501 cysts-gdry$^{-1}$. The dominant species of dinoflagellate cysts in the Southwestern Sea of Korea were Spiniferites bulloideus and Scrippsiella trochoidea, which are autotrophic species. To investigate the environmental characteristics of the Southwestern Sea of Korea using the dinoflagellate cysts, a principal component analysis (PCA) was conducted using the data collected from a total of 51 stations. From the score distribution map by the PCA, the Southwestern Sea of Korea was largely divided into three regions according to the first primary component and the second primary component. In other words, Group 1 was the western sea area of Mokpo and Jindo, Group 2 was the outer sea area of the South Sea, and Group 3 was the coastal areas of the South Sea around the Archipelago. It was found that this division of sea area was influenced by effects of the sea environment of the coastal areas of Korea. The coastal areas of Mokpo and Jindo that belong to Group 1 were affected by the cold Yellow Sea water. The outer sea area of the central parts of the South Sea that belong to Group 2, which is the boundary between the Southern coastal water of Korea and the Tsushima warm water, was subject to the formation of temperature fronts throughout the year, while Group 3 was affected by the coastal waters of Korea. It was also found that this division was in close relationship with the distribution of sediment facies in the bottom layer. From the above results, the environmental factors that influence the cyst distribution in he Southwestern Sea of Korea were found to include the eutrophication status of the sea area, the physical characteristics of the sea environment such as the flow of sea current and fronts, the sediment facies in the bottom layer, and the appearance volume of motile cells.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2005.11a
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• pp.44-52
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• 2005

The study, using sequence analysis and phylogenetic relationship of the fusion protein gene, divided the Korean epizootic isolates of Newcastle disease virus (NDV) into several lineages to determine the molecular epidemiology of the virus. A 695 base pair fragment was amplified by polymerase chain reaction between matrix protein gene and fusion protein gene of 30 Korean NDV isolates, which were isolated from field outbreaks of Newcastle disease between 1949 and 2002. All isolates showed the amino acid sequence 112 R-R-Q/R-K-R116 at the C-terminus of the F2 protein and phenylalanine (F) at the N-terminus of the F1 protein, residue 117. These amino acid sequences were identical to a known virulent motif. The region of the F gene between nucleotides 47 and 435 was compared by phylogenetic analysis. Based on nucleotide sequence, the Korean NDV isolates belonged to genotype III, V, VI and VII corresponding to isolates in 1949, 1982 to 1984, 1988 to 1997, and 1995 to 2002, respectively. These data showed that genotypes of five Korean Newcastle disease epizootics had replaced each other serially (III, V, VI and VII) in chronological order. Further, the five Korean Newcastle disease epizootics were closely related with the Necastle disease panzootics or Newcastle disease epizootics in other countries. Present study showed that the Korean genotype V isolated before 1984 was related with European Newcastle disease epizootics in the 1970s, whereas the Korean genotype VI and VII isolated after 1988 were more closely related with Far East Newcastle disease epizootics, especially Newcastle disease3 epizootics in Japan, Taiwan and China. Since 1988, the genotype VI and VII of Far East origin were dominant in South Korea. That might be due to the increased trade of agricultural products including poultry among Far East Asian countries.

• Korean Journal of Ecology and Environment
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• v.36 no.1 s.102
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• pp.29-37
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• 2003

Benthic macro-invertebrates were seasonally collected in the Onchen Stream in Pusan, from July 2001 to March 2002. Generally 4 phylum 5 class 10 order 19 family 23 species were observed in the study sites. Ephemeroptera, Plecoptera and various species appeared in headwater stream while Oligochaeta and Chironomidae were dominated in downstream sites. Community abundance patterns, especially the dominant taxa, Oligochaeta and Chironomidae, appeared to be different depending upon the sampling months. Oligochaeta was usually observed in July, December and March while Chironomidae was appeared in September. The biological indices, TBI(Trent Biotic Index), BS (Biotic Score), BMWP (Biological Monitoring Working Party)were calculated with the appeared communities of the sampling sites through the survey months. TBI showed 1 to 8, BMWP was 1 to 93 and CBI appeared 9 to 387 in the different sites. The biological indices decreased from headstream to downstream sites, We implemented the unsupervised Kohonen network for patterning of community abundance of the sampling sites. The patterning map by the Kohonen network was well represented community abundance of the sampling sites. Also, we conducted RTRN (Real Time Recurrent Neural Network) for predicting of the biological indices in the different sites. The results appeared that the predicting values by RTRN were well matched field data (correlation coefficient of TBI, BMWP and CBI were 0.957, 0.979 and 0.967, respectively).

• Journal of Life Science
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• v.25 no.11
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• pp.1244-1254
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• 2015

Naturalized plants were identified and recorded in Busan city based on field surveys and related literature. These plants consisted of 156 taxa in total, belonging to 31 families, 95 genera, 147 species, and 9 varieties. The Compositae had the highest diversity among 31 families, with 44 taxa, followed by Gramineae, with 24 taxa, and Leguminosae, with 10 taxa Among the plants, 68.6% (107 taxa) were annuals and biennials, and 30.1% (47 taxa) were perennials. There was one shrub (Amorpha fruticosa) and one tree (Robinia pseudoacacia). Naturalized degree 5 plants, as common and abundant plant, founded 26 taxa (96.3%) were most highly ratio from Korean naturalized plants. According to the results of the analysis based on place of origin, 50 (32.1%) taxa were from Europe, and 48 (30.8%) taxa were from North America. Epecophyten was the most common of the naturalized plants, with 123 taxa Sixty-six (42.3%) taxa were introduced during period 1, and 15 (9.6%) were introduced during period 4. Ergasiophygophyten (50.6%) and Kenophyten (32.1%) were the dominant plants in these introduction periods. In conclusion, Busan city acts as a conduit for the introduction of naturalized plants. A sustainable management and monitoring strategy may be needed to prevent the introduction and naturalization of plants.