• Journal of the Korean GEO-environmental Society
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• v.22 no.11
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• pp.15-21
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• 2021

Losses of both life and property increased from damage to underground pipe such as heat transmission pipe buried underground in downtown because pipes are gradually aging. Considering the characteristics of the heat transmission pipe, which is not exposed to the outside and difficult to immediately identify problems such as damage, it is realistic to indirectly check the condition of the facility based on the historical information that is periodically collected through facility maintenance. In this study, a methodology for estimating the damage probability was developed by examining the history information of the heat transmission pipe, deriving an evaluation factor that is related to the damage probability. The contribution factor of the damage probability were reviewed by analyzing not only the guidelines for maintenance of heat transmission pipe of advanced European countries and domestic district heating companies, but also the cases of waterworks with similar characteristics. Evaluation factors were selected by considering not only the correlation with the damage probability but also the possibility of securing data. Based on 1999, when the construction technology and standards of heat transmission pipe changed, the damage probability estimation function according to the period of use was divided into the case of being buried before 1998 and the case of being buried after 1999, and presented. In addition, the damage probability was corrected by assigning weights according to the measured data for each evaluation factor such as the diameter, use, and management authority.

• KIPS Transactions on Software and Data Engineering
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• v.10 no.10
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• pp.391-398
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• 2021

Since the leased line is a structure that exclusively uses two connected areas for data transmission, a stable quality level and security are ensured, and despite the rapid increase in the number of switched lines, it is a line method that is continuously used a lot in companies. However, because the cost is relatively high, one of the important roles of the network operator in the enterprise is to maintain the optimal state by properly arranging and utilizing the resources of the network leased line. In other words, in order to properly support business service requirements, it is essential to properly manage bandwidth resources of leased lines from the viewpoint of data transmission, and properly predicting and managing leased line usage becomes a key factor. Therefore, in this study, various prediction models were applied and performance was evaluated based on the actual usage rate data of leased lines used in corporate networks. In general, the performance of each prediction was measured and compared by applying the smoothing model and ARIMA model, which are widely used as statistical methods, and the representative models of deep learning based on artificial neural networks, which are being studied a lot these days. In addition, based on the experimental results, we proposed the items to be considered in order for each model to achieve good performance for prediction from the viewpoint of effective operation of leased line resources.

• Journal of Aerospace System Engineering
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• v.15 no.5
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• pp.81-88
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• 2021

In general, a non-explosive nylon wire cutting-based holding and release mechanism has been used to store and deploy deployable solar panels of CubeSat. However, with this method, accessing the solar panel's access port for charging the cube satellite's battery and electrical inspection and testing of the PCB and payloads while the solar panel is in storage is difficult. Additionally, the mechanism must have a reliable release function in an in-orbit environment, and reusability for stow and deploy of the solar panel, which is a hassle for the operator and difficult to maintain a consistent nylon wire fastening process. In this study, we proposed a pin-puller-based solar panel holding and release mechanism that can easily deploy a solar panel without cutting nylon wires by separating constraining pins. The proposed mechanism's release function and performance were verified through a solar panel deployment test and a maximum separation load measurement test. Through this, we also verified the design feasibility and effectiveness of the pin-puller-based separation device.

• Korean Journal of Environment and Ecology
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• v.35 no.2
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• pp.204-219
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• 2021

This study was conducted to investigate and analyze the characteristics of the plant community structure of vegetation distributed on the western slope and ridge connecting Mt. Noja to Mt. Gara. This basic research was executed not only to restore and manage forest vegetation, but also to monitor the trend of change in the long term. As a result of classifying the communitise in 86 survey quadrats, the Pinus thunbergii-Platycarya strobilacea comm. and P. thunbergii-P. densiflora comm. were distributed around the lowlands. The Carpinus tschonoskii-Deciduous broad-leaved comm., Styrax japonicus-Deciduous broad-leaved comm., Acer pictum subsp. Mono-Deciduous broad-leaved comm., Deciduous broad-leaved comm., and Zelkova serrata comm. appeared in the valley and all stone areas. Quercus serrata comm., Q. serrata-S. japonicus comm., S. japonicus-Carpinus cordata comm., Euonymus oxyphyllus comm. were classified as being distributed on steep slopes with relatively high altitude. According to the succession trend of the forest, evergreen conifers will be transition to deciduous broad-leaved trees. However, deciduous broad-leaved arboreous forests, such as Carpinus tschonoskii, zelkova serrata, and Acer pictum subsp. Mono, were considered to maintain their current succession stage because not only the stratified structure was developed over about 50 years tree age, but also ecologically stabilized. As environmental factors, it was analyzed that altitude, pH, content of clay and silt, Mg⁺⁺, Ca⁺⁺, etc. directly or indirectly affect the distribution of plant communities.

• Journal of the Korean Institute of Gas
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• v.25 no.3
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• pp.39-45
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• 2021

Scrubbers that treat hazardous materials at workplaces have high treatment efficiency; however, the design is complex, and pumps need to be operated 24 hours a day, which can be costly. Therefore, to minimize the operating costs, small businesses do not install scrubbers, or operate them while circulation pumps are suspended. Hence, this study investigated the application of low-cost, high-performance scrubbers that can be used economically in small businesses. Low-cost, high-efficiency scrubbers are applied to bubble columns to utilize devices for hazardous chemical absorption treatment purposes, and for the development of these scrubbers, absorption performance was reviewed and the optimal application method was studied under certain conditions. The changes in the absorption performance of hazardous gas were studied in certain environments by varying the physical conditions, and the optimal application methods were analyzed. The results showed that, while it was possible to treat some of the gas flowing into the low cost, high performance scrubber, the treatment capacity was reduced. Performance degradation was prevented by supplying an absorption liquid, and a certain level of absorption was maintained depending on the amount of circulation. Based on this, three types of site application methods of low cost, high performance scrubbers were presented. In addition, the appropriate timing of circulation and anti freezing measures were also discussed.

• Korean Journal of Organic Agriculture
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• v.29 no.2
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• pp.209-221
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• 2021

The purpose of this study is to obtain basic data on housing facilities and management of broiler welfare certified farms in Korea. We investigated breeds, flock sizes, stocking density, perches, litter, plumage condition, and other diseases. In addition, we measured temperature, relative humidity, light intensity, ammonia, and carbon dioxide concentration in the barn. As result, criteria were met in all cases that we investigated. However, farmers commonly demanded relaxation of perch and litter. Perch usage of broiler was impractical due to low usage of it. Also, litter was increased, resulting in farmers' economic burden by the imbalance between supply and demand. This situation makes farmers reuse the litter. Unfortunately, there are no clear certification standards. During re-inspection, the animal welfare certification of farms was canceled due to the reuse of litter. It is difficult to modify the standard of perch due to the strong declarative meaning of animal welfare rather than the necessity of perch usage, however, the reuse of litter should be improved. It is important to think and solve any problems faced by all farms. Especially, animal welfare standards need to be improved in more clarity and rationality.

• International Area Studies Review
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• v.15 no.2
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• pp.403-425
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• 2011

Canada became the first OECD/DAC member state that legislated the ODA Accountability Act in 2008, which prescribe Canada ODA policies to meet the guidelines and norms of international human rights while other OECD/DAC member states was just emphasizing the importance of abiding by the international human rights norms. Paying attention to the Canadian case, this article critically examines under what structural environments and process this Act was passed. This article argues that the legislation of the ODA Accountability Act is closely related with Canada's international position as middle power and diplomatic strategies. Bring up the human security issues as a niche market, Canada demonstrates the characteristics of middle power state by emphasizing human rights agenda as new foreign policy strategies. Reflecting on the negative outcomes from neoliberal aid policy of structural adjustment and promoting the new aid norms in post cold war era would also help foster the enabling environment for the value-oriented aid policies and enactment of the Accountability Act. Civil society organizations were also playing catalyst role in constructing Canada's state identity of human rights defender.

• Cross-Cultural Studies
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• v.46
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• pp.1-20
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• 2017

This study tries to examine the emotion of the elite characters in Son Jangsoon's early novel, The Koreans. In this novel, most characters are found to have an envy feeling, except for two female characters, Heeyeon and Sue Han. Although the writer does not consciously explore the envy feeling here, she excellently represents the harmful effects of the envy feeling. In this novel, the envy feeling is related to the desire for success and its frustration. In 1960's, people had high expectation of improvement in their individual lives. The elite groups were more likely to have a successful life with good education. But in this novel, these elite people suffer from frustration of their desire and experience of the envy feeling. The impressive point in this novel is that not only females but also males are shown to have the envy feeling. Envious people have the tendency to compare themselves with people around them, to feel shame in an inferior position and to aspire for superiority. In these envious characters, the feeling of envy reveals their lack, their inferiority and it never provides them with the way to escape from their suffering situation. The writer suggests that the envy feeling can be overcome by pursuing other valuable things and focussing not on other people's desire but on their own desire.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.4
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• pp.121-128
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• 2019

The purpose of this study was to investigate the effects of exercise program intervention in Korea for the control of blood sugar levels in elderly women patients undergoing diabetes mellitus typeII and to investigate the effects of exercise program intervention. Research methods were searched through RISS, KISS, KoreaMed, and KMbase as domestic databases and limited to domestic papers published from 2010 to May 2017. Diabetes, female diabetes, and diabetes mellitus typeII were used as the search terms related to the patient group. Programs related to intervention, intervention, exercise, blood glucose, glucose insufficiency, glucose control, fasting glucose and HbA1c were used. A total of 12 papers were provided according to the intervention method. The mediation period was 12 weeks(50%), 3 times per week(58.3%), and 50 to 69 minutes(83.4%) was the most. The combined aerobic and anaerobic exercise was found to be an effective exercise method to control not only blood glucose level but also HbA1c. Individualized exercise program intervention should be provided considering the physical fitness level and health status of elderly patients undergoing diabetes mellitus typeII and should be encouraged to maintain effective blood glucose control through continuous exercise rather than one-off exercise.

• The Journal of the Petrological Society of Korea
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• v.27 no.4
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• pp.207-222
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• 2018

Celestial Chart Stones (original and reproduction) in the National Palace Museum are representative scientific cultural heritage of Korea. Material analysis and nondestructive deterioration assessment were conducted for long-term preservation of these stones. Material analysis revealed that the original was composed of slate and the reproduction was made of dolostone. The original consists of quartz, mica, dolomite minerals, while the reproduction was made up of dolomite, calcite and forsterite. Major deterioration factors of the original stone were cracks and breakouts. In case of the reproduction, scratches and artificial materials were mainly observed. The green and black surface contaminants present at the sides and back of the two celestial chart stones were interpreted as resin-based paint materials. The physical property evaluation using ultrasonic velocity showed a low velocity in the upper left side of the original, while the front right side of the reproduction showed a weak property. Meanwhile, the To-Tc method using ultrasonic velocity was applied to major cracks that impede stability of the original. As a result, it has been calculated that the beginning and the center of the crack are the deepest.