• Journal of Korean Society of Forest Science
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• v.100 no.1
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• pp.88-94
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• 2011

This study was conducted to provide on a basic information for maintenance of roadside trees and identify the links between environmental pollution and tree damages (Ginkgo biloba, Platanus occidentalis) in Daejeon City by analyzing photosynthetic characteristics, water use efficiency, chlorophyll fluorescence and chlorophyll contents by the regions and plants. The investigations were conducted at Chungnam national university(CNU) considered as the least air-polluted area compared to other study sites, Daedeok science town(DS) which a new road with little traffic recently was built around, Daehwa industry complex(DIC) and Daejeon station(DS) which an old road with heavy is located around. The photosynthetic capacity of the two species were highest in CNU and lowest in the DS. However the water use efficiency was highest on the contrary to the photosynthetic capacity in DS. Chlorophyll fluorescence and chlorophyll contents were highest in CNU and lowest in DS as the photosynthetic capacity. On all of the test, Ginkgo biloba shows the more favorable physiological responses than Platanus occidentalis.

• Journal of Legislation Research
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• no.54
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• pp.261-301
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• 2018

In South Korea, the number of households that rear companion animal has been gradually increasing. With the rise of household dogs, the frequency of humans that are being bitten by another's dog has also increased. This type of accident, which is known as a dog bite accident throughout the United States. It can cause significant physical and emotional damage to the victims and may result in grave injuries or death. Dog bite accidents are serious public health problems and can cause immeasurable hidden costs to the community. South Korea has enacted several laws to address dog bite accidents, which include the Animal Protection Act, the Civil Act, and the Criminal Act. On March 20, 2018, the Animal Protection Act was amended to reinforce the current legislation. These amendments addressed the duty of care owed by a companion dog owner to society members and the punishment that an owner of a fierce dog would face in the event of a dog bite accident. Conversely, several states in the United States have enacted a single law that regulates the details regarding dog bite accidents, such as the type of dog or animal, the type of damage, the scope of compensation for damages, and the scope of recognition of liabilities. This paper is intended to review the present situation of dog bite legislation in several states in the United States, which have a variety of laws that address dog bite accidents, and compare them with current South Korean dog bite legislation. Through this research, this paper will discuss what issues may exist in South Korean's current dog bite laws, analyze the responsibility of companion dog owners, and provide solutions to any issues that are discovered.

• The Journal of the Korea Contents Association
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• v.21 no.1
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• pp.12-23
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• 2021

Due to high proportion of exports, Korea has a higher dependence on the global value chain (GVC) than other major developed countries. This reason, Korea has a structure that is sensitive to GVC changes. This is because Korean exports are concentrated on specific countries and items, and most of the materials for export tend to depend on imports. Currently, export restrictions resulting from trade disputes with Japan can affect the industry of Korea as a whole due to the supply of core materials. Therefore, in order to minimize economic damage caused by export regulations in the current situation, it is necessary to reorganize the GVC, through efforts to rapidly diversify imports and localize imports that depend on Japan. To this end, it is necessary to derive and classify imported goods that depend on Japan, and to localize items that are difficult to diversify imports, and prompt R&D investment is required for this. This study aims to support R&D investment policy through quantitative analysis based on big data rather than a decision-making method based on expert-centered qualitative analysis.

• Journal of Platform Technology
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• v.8 no.3
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• pp.10-21
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• 2020

Partial discharge occurs a lot in high-voltage power equipment such as switchgear, transformers, and switch gears. Partial discharge shortens the life of the insulator and causes insulation breakdown, resulting in large-scale damage such as a power outage. There are several types of partial discharge that occur inside the product and the surface. In this paper, we design a predictive model that can predict the pattern and probability of occurrence of partial discharge. In order to analyze the designed model, learning data for each type of partial discharge was collected through the UHF sensor by using a simulator that generates partial discharge. The predictive model designed in this paper was designed based on CNN during deep learning, and the model was verified through learning. To learn about the designed model, 5000 training data were created, and the form of training data was used as input data for the model by pre-processing the 3D raw data input from the UHF sensor as 2D data. As a result of the experiment, it was found that the accuracy of the model designed through learning has an accuracy of 0.9972. It was found that the accuracy of the proposed model was higher in the case of learning by making the data into a two-dimensional image and learning it in the form of a grayscale image.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.1
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• pp.29-37
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• 2021

In the event of a marine pollution accident, Korea, which is bordered by the sea on three sides, would suffer tremendous damage. According to an analysis of marine pollution accidents in Korea, most pollutants were small fishing boats and tugboats. In particular, urgent safety measures are required due to the high incidence of marine pollution accidents caused by stranded tugboats. This study aims to decrease secondary marine pollution accidents by preparing measures to prevent accidents by stranded tugboats, the main source of pollution accidents. To this end an experiment was conducted to mark 63 locations where stranded accidents have occurred on the GPS plotters of 61 tugboats operating in Boryeong sea area. Its effectiveness was then investigated. The result showed that there was no stranded accident by the subject ship during the 20-month experiment period. As a result of survey of the captains, 36 out of 40 respondents (90%) stated that the experiment was significantly helpful in ensuring safe navigation, thus confirming its effectiveness. Various measures were proposed to prevent stranded accidents, including providing information to manufacturers and users by marking the location of grounded accidents on GPS plotters and posting the location information of unknown reefs on the official website of institution Korea Hydrographic and Oceanographic Agency.

• Journal of fish pathology
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• v.33 no.2
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• pp.119-125
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• 2020

During the period from 2003 to 2020, a total of 470 Streptococcus species were isolated from farmed flounder in Jeju. Out of 470 isolates, 92 (19.6%) isolates and 378 isolates (80.4%) were identified as Streptococcus iniae and S. parauberis, respectively by multiplex PCR assay. During that period, the percentage of S. iniae decreased from 56.9% in 2003 to 0.0% in 2020 whereas that of S. parauberis increased from 43.1% in 2003 to 100% in 2020. In the PCR assay for serotyping, the isolated S. parauberis showed 3 subserotypes, Ia (34.9%), Ib/Ic (46.3%) and II (18.8%). In 2003 and 2004, serotype II was dominant at 59.1% and 50.0% of isolation rates, however between 2005 and 2009, subserotype Ib/Ic was dominant (57.6%, 86.0%, 84.6%, 57.9%, and 83.3%). After 2010, except for 2015, subserotype Ia was the most dominant one. In the last 3 years (2018 to 2020), subserotype Ia was most abundant (70%), followed by subserotype Ib/Ic (16-30%). Serotype II was not isolated in 2018, but in 2019 and 2020, it showed an increased tendency to 3.4% and 16.7%, respectively. It is believed that continuous monitoring is necessary for research on counter-measures against streptococcosis of flounder.

• Journal of Wetlands Research
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• v.23 no.1
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• pp.14-26
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• 2021

Increase of climate variability due to climate change has paved the way for regional drought monitoring and outlook. In particular, Gimcheon-si, Gyeongsangbuk-do, is suffering from frequent and periodic drought damage as the frequency and magnitude of drought are increasing due to climate change. For this reason, it is necessary to analyze drought characteristics for sub-districts based on water district and calculate the basic low-flow considering climate change. In this study, meteorological and hydrological drought outlook were carried out for 8 sub-districts considering the water supply system and regional characteristics of Gimcheon-si according to various climate change scenarios. In addition, the low-flow frequency analysis for the near future was also performed using the total amount of runoff and the low-flow. The overall results indicated that, meteorological droughts were found to be dangerous in the S0(1974~2019) period and hydrological droughts would be dangerous in the S2(2041~2070) period for RCP 4.5 and in S3(2071~2099) period for RCP 8.5. The results of low-flow frequency analysis indicated that future runoff would increase but drought magnitude and frequency would increase further. The results and methodology may be useful for preparing local governments' drought measures and design standards for local water resources facilities.

• Journal of the Korean earth science society
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• v.42 no.6
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• pp.623-631
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• 2021

The increased transport of marine hazardous and noxious substances (HNS) has resulted in frequent HNS spill accidents domestically and internationally. There are about 6,000 species of HNS internationally, and most of them have toxic properties. When an accidental HNS spill occurs, it can destroys the marine ecosystem and can damage life and property due to explosion and fire. Constructing a spectral library of HNS according to wavelength and developing a detection algorithm would help prepare for accidents. In this study, a ground HNS spill experiment was conducted in France. The toluene spectrum was determined through hyperspectral sensor measurements. HNS present in the hyperspectral images were detected by applying the spectral mixture algorithm. Preprocessing principal component analysis (PCA) removed noise and performed dimensional compression. The endmember spectra of toluene and seawater were extracted through the N-FINDR technique. By calculating the abundance fraction of toluene and seawater based on the spectrum, the detection accuracy of HNS in all pixels was presented as a probability. The probability was compared with radiance images at a wavelength of 418.15 nm to select abundance fractions with maximum detection accuracy. The accuracy exceeded 99% at a ratio of approximately 42%. Response to marine spills of HNS are presently impeded by the restricted access to the site because of high risk of exposure to toxic compounds. The present experimental and detection results could help estimate the area of contamination with HNS based on hyperspectral remote sensing.

• Journal of the Korean earth science society
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• v.43 no.1
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• pp.23-29
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• 2022

Although tropical cyclones with wind speeds weaker than 17 ms^-1 (weak tropical cyclones: WTCs) can cause significant damage, particularly over the Seoul metropolitan area, only a few studies have focused on WTC activity over South Korea. In this study, we found that WTC activity is likely associated with the Pacific Decadal Oscillation (PDO). During the negative phases of the PDO, landfall frequency of WTCs increased significantly compared to the positive phases at 95% confidence level. When related to the negative phases of the PDO, a positive relative vorticity anomaly is found in the northern sector of the western North Pacific while a negative relative vorticity anomaly and enhanced vertical wind shear prevail in the southern sector of the WNP. These factors are favorable for the northward shift of the genesis location of tropical cyclones on average, thereby reducing the total lifetime of WTCs. Moreover, a high-pressure anomaly over the Japanese islands would shift a tropical cyclone track westward in addition to the landfall location. Consequently, the effects of the topographical friction and the Yellow Sea Bottom Cold Water on a tropical cyclone may increase. These conditions could result in a weaker lifetime maximum intensity and landfall intensity, ultimately resulting in WTCs becoming more frequent over South Korea during the negative phases of the PDO.

• Journal of the Korean Geotechnical Society
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• v.37 no.11
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• pp.51-60
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• 2021

River scour erodes the soil around the pier, reducing the lateral bearing capacity of the pier and lowering the stability of the structure. In this study, in order to examine the effect of scouring on the stability of the structure, an experiment was performed to measure the natural frequency of the pier according to the excavation of the surrounding ground. Impact vibration test was conducted on the pier with the caisson foundation of the Mangyeonggang Bridge, which is scheduled to be demolished. Accelerometers were attached to the top, center, and bottom of the pier and the acceleration responses were measured by hitting those three points. The experimental results showed that the top hit showed consistent and reasonable results of the acceleration responses according to the hitting position. The measured accelerations were converted to the frequency domain through Fast Fourier Transform (FFT), and then the natural frequency was determined. In addition, to analyze the scour effect on the natural frequency of the pier, the ground around the pier was excavated and the natural frequency change was analyzed. As a result, the natural frequency showed the decreasing tendency according to the excavation depth, but the decrease was small due to the large stiffness of the caisson foundation.