• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.1
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• pp.10-18
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• 2022

With the increase in world trade through ships, the destruction of the marine ecosystem and socioeconomic damage due to invasive alien species (IAS) are continuously increasing. In particular, marine organisms attached on the hull surface and niche area increase the friction resistance of ships as well as the invasion of non-indigenous species, and causes a decrease in operational efficiency and an increase in GHG (Green House Gas) emissions. The International Maritime Organization (IMO) has recently begun revising guidelines for the control and management of ship's biofouling, and New Zealand and California in the United States are already regulating biofouling management under their own laws. This study investigated the management status of the submerged surface of ships and marine organisms attachments on five international ships entering South Korea, and analyzed species group and coverage (%) of biofouling communities to evaluate the LoF (Level of Fouling) rank. Macroflouling was observed on all ships surveyed, and specially, the adhesion of macro organisms in niche areas such as bow thruster, bilge keels and sea-chest gratings appeared to be at a serious level. This study proposed the management direction our country should take with regard to ship's biofouling and the improvement measures for evaluation of LoF rank and inspection methods of hull and niche ares.

• Industry Promotion Research
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• v.7 no.3
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• pp.85-91
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• 2022

In modern society, the field of life is expanding to complex and diverse fields according to changes in lifestyle. As people's consciousness also changes, various social problems are involved, and countermeasures are being taken in various ways. In particular, as the issue of school violence has become a subject of interest, government-related ministries have jointly set up a reporting center and professional counselors are receiving and consulting on damage reports. Counselors experience mental and physical exhaustion in the course of their work. Therefore, the need to contribute to effective counseling work is raised by studying the factors that cause burnout. This study collected the experiences of 10 counselors working at 117 reporting centers from February 2019 to May 2020 through interviews and analyzed them with Colaizzi's phenomenological research method. The exhaustion factors derived from the results of the study were first experiences such as conflict between counselors during the period of institutional integration in the "117 reporting center experience", and secondly, professional counselors experienced emotional exhaustion, inhumanization, and lack of achievement. In order to prevent and overcome the exhaustion factors of counseling agents, it was necessary to prepare measures to promote fraud. This is expected to be useful data for improving the working environment of special job counselors in the era of industrialization and informatization in which various anonymous counseling methods are used.

• Journal of the Korean Geotechnical Society
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• v.38 no.6
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• pp.5-16
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• 2022

In the case of domestic seismic design, deformation of structures and ground is reviewed through undrained condition analysis and applied to design and maintenance. However, when the ground undergoes dissipation after liquefaction due to a dynamic load such as an earthquake, additional displacement occurs and greater damage occurs. Therefore, it is necessary to additionally analyze the drained conditions, It is necessary to grasp the exact ground behavior such as calculating and reviewing the amount of subsidence of the ground that has undergone the loss process after an earthquake and apply it to design and maintenance together. Therefore, in this study, numerical analysis was performed assuming undrained and drained conditions by dividing pure sandy soil into loose soil with Dr=30% and high-density soil with Dr=70%. In particular, when a dynamic load such as an earthquake is applied, considering the drained conditions of the ground, the settlement amount and the pore water pressure ratio of loose and dense ground are compared, This study focused on comparative analysis of settlement amount and pore water pressure ratio in the process of ground loss after an earthquake. As a result, the amount of subsidence during the dissipation process was 30 to 60 times greater than that of the earthquake.

• Korean Journal of Plant Resources
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• v.36 no.1
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• pp.100-106
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• 2023

In order to control the fire blight disease, all plants within the radius of the diseased orchard were removed in the early stage of the outbreak, or antibiotics control was performed for prevention. Since the beginning of antibiotics use on plants, the potential for development of resistance to antibiotics by the plant pathogen and unintended detrimental effects on the fruit trees and environment has become a problem. The purpose of this study is to determine the degree of phytotoxicity to fruit trees caused by excessive spraying of the fire blight disease disinfectant and to establish basic data for safe disinfectant guide. We analyzed whether damage to the fruit tree and the maximum residual limit of fruit was exceeded when three kinds of the fire blight disease disinfectants were continuously sprayed in excess of the number of safe use during the growing season. There was no phytotoxicity in apple 'Fuji' and pear 'Niitaka', and oxolinic acid was detected beyond the limit of quantitation in 'Fuji' grown without a bag, and the other disinfectants were detected below the maximum residue limit. When these disinfectants are continuously sprayed in excess of the number of safe, phytotoxicity may remain on the fruit. Therefore, it is necessary to observe the prescribed dilution factor and observe the safe frequency and the timing of use.

• Journal of Environmental Health Sciences
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• v.48 no.6
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• pp.324-330
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• 2022

Background: Lung injuries due to exposure to humidifier disinfectants (HDs) were reported in 2011 in South Korea. As a result of the government's epidemiological investigation and toxicity test study, it was found that HDs caused health damage such as lung disease. Objectives: The purpose of this study was to classify HD exposure ratings and analyze the affecting factors that could identify the relationship with lung disease. Methods: Exposure assessment for HDs was conducted using a questionnaire during face-to-face interviews with the applicants. Ratings of high exposure (Class 1) and low exposure (Class 2) were cross-tabulated with clinical ratings (acceptable and unacceptable). Logistic regression analysis was carried out by setting the clinical rating of lung disease as a dependent variable and the socio-demographic and exposure characteristics obtained through the questionnaire as independent variables. Results: The concentration in air of polyhexamethylene guanidine (PHMG) was 71.96±107.47 ㎍/m³, and the exposure concentration was 15.21±23.28 ㎍/m³ . The exposure rating was overestimated with 97.1% of affected subjects having high exposure using margin of exposure (MOE), but only 9.9% matching the clinical class. In the overestimated group, it could be explained by the fact that the exposure time was long and the subjects had already recovered from damage symptoms. As a result of logistic regression analysis, ten variables were found to be significant influencing factors. Conclusions: A new exposure rating could be calculated based on the MOE, and factors affecting lung disease could be estimated through comparative evaluation with the clinical rating.

• Journal of Korean Society of Disaster and Security
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• v.16 no.1
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• pp.1-11
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• 2023

The comprehensive natural disaster reduction plan, the highest plan in the disaster prevention field, was implemented by local governments. second plan is currently being formulated. In order to minimize human and property damage, structural and non-structural measures for each of the nine disaster types are established and implemented for 10 years. Structural measures are based on engineering and quantitative analysis, and the criteria for setting reduction measures are clear. Non-structural measures, however, currently lack the set criteria. the basic disaster and safety management law included the safety vulnerable class in 2018. Currently, the safety vulnerable class of the detailed establishment criteria of the comprehensive natural disaster reduction plan is being established, including children, the elderly, and the disabled. However, due to the lack of data securing and database construction by local governments, it is difficult to prepare a location map for establishing reduction measures for the safety vulnerable. Therefore, in this study, OPEN API data of the safety vulnerable class were collected and statistical information and GIS of SGIS information services were used. The distribution diagram of the safety vulnerable class in Samcheok, Gangwon-do, which is a sample area, and the distribution diagram of the safety vulnerable class in units of the output area (OA) in Geundeok-myeon were prepared.

• Journal of Korean Society of Forest Science
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• v.112 no.3
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• pp.382-392
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• 2023

Recent reports have indicated a rapid increase in the frequency of sediment disasters due to climate change and other changes in the geological environment. Given this alarming situation and the recent increase in the frequency of land creep in Korea, systematic and efficient recovery and management of land creep areas is essential. The purpose of this study is to identify disaster vulnerability by conducting a physical exploration of land creep in San 4-1, Jayeon-ri, Gaegun-myeon, Yangpyeong-gun, Gyeonggi-do, and examine stability by identifying the overall geological structure of the affected ground. In addition, drilling surveys are conducted to verify the reliability of the measured data. The results of the study reveal that low specific resistance abnormalities are distributed in the upper part of the soil layer and weathering zone and that this section is a 50-120 m exploration line. It is also confirmed to be a low-hardness ground area where tensile cracks are observed. Therefore, there is a need for research focused on developing measures to reduce economic and social damage within the domestic context by continuously monitoring indicators of land creep and identifying land creep risks.

• Analyses & Alternatives
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• v.7 no.1
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• pp.45-81
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• 2023

This paper examines how Korean economy has been asymmetrically changed after economics crises. The three crises during the last three decades, covid19, global financial crisis, and currency crisis, have deteriorated the economic inequalities of Korea in various ways. First, manufacture industry has been affected larger by economic crises, but recovered fast. The shocks in service sector were small but persist longer or were permanent. Second, although the covid19 spreaded out more to the capital area, the negative economic shock was greater in the non-capital region. That is, the crisis in the capital region transferred or amplified to the other region. Third, the inequality between permanent and temporary workers became worse after crises. Fourth, the sluggish small business growth problem became more serious during the covid19. In order to overcome the industrial and labor inequality, it is desirable to government strategy for economic development from focusing on high value-added industry to a balanced growth for all industry and region. To this end, governemt support should be asymmetric. That is, it should focus on indirect support such as regulatory reforms in the high value-added and private-led industries, and, for small business related service sector and non-capital region which have had limited opportunity of renovation and growth, the more active effort of government and government-driven gowth strategy would be desirable.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.10a
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• pp.562-565
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• 2022

Recently, the increasing number of overloaded vehicles on the road poses a risk to traffic safety, such as falling objects, road damage, and chain collisions due to the abnormal weight distribution, and can cause great damage once an accident occurs. However, this irregular weight distribution is not possible to be recognized with the current weight measurement system for vehicles on roads. To address this limitation, we propose to build an object detection-based AI model to identify overloaded vehicles that cause such social problems. In addition, we present a simple yet effective method to construct an object detection model for the large-scale vehicle images. In particular, we utilize the large-scale of vehicle image sets provided by open AI-Hub, which include the overloaded vehicles from the CCTV, black box, and hand-held camera point of view. We inspected the specific features of sizes of vehicles and types of image sources, and pre-processed these images to train a deep learning-based object detection model. Finally, we demonstrated that the detection performance of the overloaded vehicle was improved by about 23% compared to the one using raw data. From the result, we believe that public big data can be utilized more efficiently and applied to the development of an object detection-based overloaded vehicle detection model.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.3
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• pp.277-286
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• 1985

From a series of studies conducted on the local maize lines at the Agr. College of the Chungnam National Univ., a few maize lines with many tillers and ears per plant were identified and tentatively named as MET. The purpose of the study was to evaluate the MET lines, which were selfed for five generations, for silage purpose under the different plant densities. A hybrid, Suwon #19 and a synthetic variety, Puyo #3${\times}$#2, were included for comparison. Plant height at harvesting times showed no significant varietal differences. However, the MET lines were very slow in early plant growth compared to the hybrid or synthetic variety, probably due to inbreeding depression of the MET lines. Total fresh weight at the harvesting times was highest in the MET 1 line. The MET 1 line was about 2,000 kgr. per 10a. higher than the hybrid at the harvesting time. The highest fresh weight was obtained when grown under the plant density of 60 ${\times}$ 20cm. Total dry weight per unit area showed the same tendency as the fresh weight. Total dry weight of MET 1 line was about 2.4 tons per 10a., which was about 10% higher than the hybrid, Suwon #19. As the fresh weight, the total dry weight was also highest in the plant density of 60 ${\times}$ 20cm. The grain yield per 10 are of MET 1 was comparable to the grain yield of the hybrid, especially in the low plant density, 60 ${\times}$ 40cm. The average number of effective tillers of MET lines were 4.5, while the mean tiller number of the hybrid or synthetic variety were none. However, the lodging was one of the problem for growing MET lines. The 100 kernel weight of MET lines was about 9 gr., while the 100 kernel weight of the hybrid or synthetic variety was about 30 grm.