• Journal of Korea Water Resources Association
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• v.53 no.8
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• pp.583-595
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• 2020

In this study, using the RCP scenario for Hyoja Drainage subbasin of Cheonggyecheon, we analyzed the change with the Historical and Future rainfall calculated from five GCMs models. As a result of analyzing the average rainfall by each GCMs model, the future rainfall increased by 35.30 to 208.65 mm from the historical rainfall. Future rainfall increased 1.73~16.84% than historical rainfall. In addition, the applicability of LID element technologies such as porous pavement, infiltration trench and green roof was analyzed using the SWMM model. And the applied weight and runoff for each LID element technology are analyzed. As a result of the analysis, although there was a difference for each GCMs model, the runoff increased by 2.58 to 28.78%. However, when single porous pavement and Infiltration trench were applied, Future rainfall decreased by 3.48% and 2.74%, 8.04% and 7.16% in INM-CM4 and MRI-CGCM3 models, respectively. Also, when the two types of LID element technologies were combined, the rainfall decreased by 2.74% and 2.89%, 7.16% and 7.31%, respectively. This is less than or similar to the historical rainfall runoff. As a result of applying the LID elemental technology, it was found that applying a green roof area of about 1/3 of the urban area is the most effective to secure the lag time of runoff. Moreover, when applying the LID method to the old downtown area, it is desirable to consider the priority order in the order of economic cost, maintenance, and cityscape.

• Korean Journal of Organic Agriculture
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• v.22 no.4
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• pp.773-787
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• 2014

Bacterial pustule of soybean caused by Xanthomonas axonopodis pv. glycines is one of the most prevalent bacterial diseases in many areas where soybeans are grown. This study was carried out to evaluate the effect of cultivars, sowing date and cropping system on the suppression of soybean bacterial pustule in the field. One hundred soybean cultivars were screened for disease resistance against bacterial pustule in naturally infested field. Among them, fourteen cultivars including 'Pureun' were found to be high resistant. And thirty cultivars showed to be moderate resistant(less than 3% of diseased leaf area). When Soybean cultivar 'Taekwang' were sown in four different dates, May 25, June 5, June 15, and June 25, at 10 day-interval in Milyang, the diseased leaf area of bacterial pustule was 23.3%-25.7%, 14.7%-18.0%, 10.7%-12.8%, and 1.0%-2.7%, respectively. The lowest percentage of diseased leaf area was recorded in the plots sown on June 25, whereas the highest percentage of diseased leaf area was recorded in the plot sown on May 25. As sowing time was delayed, incidence of soybean bacterial pustule found to be comparatively reduced. From December in 2006 to June in 2007, we surveyed the pathogen population of soybean bacterial pustule in five cropping upland soils where soybean was cultivated. The survey result showed the bacterial pustule pathogens were detected from the all cropping soils. The pathogen populations of soybean bacterial pustule in soybean-barley and soybean-garlic cropping soil were significantly lower than that of the other cropping soils. In addition, the incidence of soybean bacterial pustule was decreased under the two cropping systems.

• Journal of Food Hygiene and Safety
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• v.17 no.3
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• pp.129-136
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• 2002

This study was conducted to Provide basic information Promoting egg qualify improvement and hygienic control by grasping of present market egg distribution system and hygienic quality. The eggs of 57 brands collected from the department food stores in Incheon Metropolitan City were examined. Eggs were kept in room temperature in all the market and 70.2% of the brands were marked the expiration date indicating that eggs would be available over 28 days after being laid. Fifty-four % of the market eggs was classified as a special or functional egg. Expiration date and date of laying were common labelling items in all brands. These items were labelled in trade mark sheet or eggs tray. Only 66.6% of the brands had the mark about net quantity of contents. The inspection about the exterior and contents of eggs has results as follows: eggshell contamination of feces and feather-9.5%, abnormal and broken eggshell -3.9%, blood and meat spots in contents -14.7% and watery whites -1.8%. Average of Haugh Unit(HU) was 56.1 and below HU 31 were 18 of 285 eggs(6.3%), in addition, more than one egg detected in 12 brands(21.1%) among 57 brands have inferior quality. Salmonella enteritidis from eggshell and antibodies directed from S. enteritidis in the yolks of eggs available in the market were not detected. Ranges of Total bacterial count (CFU/ml) on eggshell of eggs were < 10~8.2$\times$10$_3$, and isolation ratio of Escherichia coli were 4.7%. Tetracyclines were detected in 1.8% of the eggs(1 of57 brands) by CHARMII. As mentioned above, quality control and improving distribution system were required to facilitate egg consumption and improve public health by complementing labelling items and quality standards.

• Korean Journal of Plant Resources
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• v.27 no.2
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• pp.155-173
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• 2014

The habitats characteristics of Exochorda serratifolia were investigated to compile basic data for conservation and restoration. Natural habitats were located at an altitude of 1 m to 624 m above sea level with angles of inclination ranging from 2 degrees to 81 degrees. A total of 248 vascular plant taxa were identified from 37 quadrats in 16 habitats. The importance value of Exochorda serratifolia is 18.70%, and 5 highly ranked species such as Rhododendron mucronulatum (3.79%), Abelia tyaihyoni (3.27%), Euonymus alatus for. ciliatodentatus, Quercus mongolica (3.23%), and Indigofera kirilowii (2.97%) are considered to be an affinity with Exochorda serratifolia in their habitats. Species diversity was 1.03, dominance and evenness were found to be 0.15 and 0.85, respectively. Average field capacity was 24.19%, the organic matter was 8.21%, pH was 5.52, and available phosphorus was $7.71{\mu}g/g$. Correlation coefficients analysis based on environmental factors, vegetation, and soil analysis shows that the coverage of Exochorda serratifolia is correlated with field capacity and available phosphorus.

• Journal of Plant Biotechnology
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• v.47 no.4
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• pp.261-272
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• 2020

Approvals for cultivation and import of genetically modified (GM) crops have dramatically increased around the world. Comparative compositional studies are an important aspect of safety assessments of products from GM crops and are based on substantial equivalence. Compositional analyses focus on determining similarities and differences between the compositions of the GM crops and their conventional counterparts, and thereby assessing the compositional equivalence of GM crops and their conventional comparators. The analytes, such as major constituents, key nutrients, and antinutrients, are generally determined on a crop-specific basis according to the OECD consensus document. The use of standard methods throughout the processes, such as selection of comparators, field trials, analytical methods, and statistical data analysis, is crucial. In this study, we showed the general framework of compositional studies. Literature for compositional studies of GM crops conducted abroad and in Korea was reviewed to obtain information about analytes, conventional counterparts, cultivation year, location, and statistical methods. The studies conducted abroad assessed for commercial release of GM crops such as soybean, maize, and cotton, while domestic studies were mainly performed for research in rice. In addition, we suggested a guidance for conventional comparators and field trials applicable to the domestic situation.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.27 no.1
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• pp.25-33
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• 2021

This experiment was conducted to determine the effects of the pre- and post-harvest variable factors on the processed product of kimchi cabbage cultivated in semi-highland at summer time. Kimchi cabbage cultivar 'Chun Gwang' was grown in an open field and/or under a plastic greenhouse condition; it was stored at 0? after harvesting with low-density polyethylene (LDPE) film packaging. The pre-harvest characteristics growth parameters, fresh weight, head weight, no of leaves, leaf thickness, firmness, moisture content etc. were evaluated. The evaluated postharvest characteristics were fresh weight loss, appearance, trimming loss, SPAD value, moisture content and hue angle. The results show that the fresh weight and leaf thickness were higher in 'Chun Gwang' kimchi cabbages grown in the greenhouse than those in the field. However, the other evaluated factors were not affected by the type of cultural method. During the storage, the cabbage continued to decrease in fresh weight loss, trimming loss and moisture content. When compared to the kimchi cabbage showed significant difference in the fresh weight loss, trimming loss and moisture content during storage. It was confirmed that both cultural methods indoor- and outdoor did not show head growth parameters of 'Chun Gwang' kimchi cabbages on semi-high land at summer time. Although no difference in the growth before storage was observed, the evaluated characteristics like fresh weight loss etc. were influenced by cultural method as a pre-harvest factor. This study suggests that there were to be affected by pre-harvest factor during storage after harvest. In this study, an integrated management system combining relationship between processed agricultural products and their pre- and post-harvest factors.

• Korean journal of applied entomology
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• v.58 no.3
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• pp.251-258
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• 2019

A series of studies were conducted to monitor the seasonal occurrences of onion thrips (Thrips tabaci) and allium leafminers (Acrolepiopsis sapporensis) in northern-type garlic fields, and to evaluate their susceptibility to insecticides. The results showed that the T. tabaci population density increased from mid- March to mid-June, that of A. sapporensis began to increase in mid-March and peaked twice by early July. Also, using recommended concentrations, the insecticidal activities of nine insecticides against these two pests were evaluated. Under laboratory conditions, clothianidin SC, chlorfenapyr EC, dimethoate EC, imidacloprid WP, and cyantraniliprole + thiamethoxam WG insecticidal activities against T. tabaci were all 100%, as well as. those of cyantraniliprole EC, pyridalyl EW, spinetoram SG and abamectin + chlorantraniliprole SC against A. sapporensis. Insecticides, with high insecticidal activities, were evaluated on the two pests under laboratory conditions, and the results showed that all the insecticides exhibited strong insecticidal activities, and the mortality of two pests was >90%.

• Research in Plant Disease
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• v.25 no.3
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• pp.143-148
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• 2019

An outbreak of new disease with leaf and stem blight symptom occurred at bracken-growing fields in Namhae-gun, Gyeongsangnam-do, Korea during the last 4 years. This new disease caused significant yield losses on bracken production in this area. We have collected diseased leaves and stems showing the blight symptom in May, July, and October 2018 to investigate causal pathogens. A total of 92 fungal isolates were obtained from the diseased samples and their pathogenicity was tested on healthy bracken leaves. From the total isolates, 22 isolates were able to produce the leaf blight symptom similar to the original one found in the fields. To identify two fungal pathogens which showed higher virulence levels compared to other pathogenic isolates, we constructed phylogenetic trees using the nucleotide sequences of genes for ribosomal RNA, RNA polymerase beta subunit, beta tubulin, and internal transcribed region. Most phylogenetic trees constructed indicate that both isolates, which are identical to each other, reside in a clade of the genus Didymella and possibly similar to D. rumicicola or D. acetosellae. Nevertheless, the exact identification of these pathogens at the species level needs further investigations. This is the first report of a blight disease on bracken by Didymella sp.

• Journal of the Korean Geotechnical Society
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• v.38 no.3
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• pp.17-26
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• 2022

Domestic district heating system needs safety management guidelines using the change of surface temperature to detect damages to buried heat pipes. This paper performed numerical analyses on the temperature change of ground surface due to the burial and leakage of heat pipes. Temperature difference between the ground surface above the buried heat pipes and the surrounding surface rises to a crescendo between 3 am and 8 am. It is more significant in winter rather than in summer. Low groundwater level magnifies the temperature increase of the ground surface by the heat pipe, which is smaller in the asphalt pavement than in the bare soil. Without leakage of the buried heat pipe, the temperature increment on the ground surface by the heat pipe is within 3.0℃ in the bare soil and 3.5℃ in the asphalt pavement. Leakage of the supply heat pipe in the bare soil increases the temperature on the ground surface gradually in the summer but rapidly in the winter. Asphalt pavement shows a lower increment and increasing rate of the temperature on the ground surface due to pipe leakage than bare soil surface. And leakage on both sides of the supply pipe takes 1-2 days for the temperature difference from the surrounding soil surface to reach 10℃.

• Korean Journal of Construction Engineering and Management
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• v.25 no.2
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• pp.45-55
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• 2024

This study analyzed the efficiency determinants of specialty construction companies by industry using the DEA model and the Tobit model. The analysis targets are 394 specialty construction companies as of 2022. As a result of analysis of efficiency determinants using 12 company characteristics as independent variables, the biggest problem for specialty construction companies was overall efficiency reduction due to rising labor costs. In addition, in a situation where construction companies' loan regulations are severe, the debt ratio was found to have a positive effect on efficiency. Company size had a different impact by industry, and the number of businesses held, credit score, and total capital turnover had an effect only on some industries. This study presents results that are an advance on existing research in that it strategically analyzes factors for improving the efficiency of specialty construction companies. However, it has limitations such as limiting the analysis to only specialty construction companies subject to external audit, insufficient number of companies subject to analysis by industry, and analyzing relative efficiency in the same category for each industry.