• Korean Chemical Engineering Research
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• v.62 no.1
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• pp.36-43
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• 2024

Fishing net waste (FNW) constitutes over half of all marine plastic waste and is a major contributor to the degradation of marine ecosystems. While current treatment options for FNW include incineration, landfilling, and mechanical recycling, these methods often result in low-value products and pollutant emissions. Importantly, FNWs, comprised of plastic polymers, can be converted into valuable resources like syngas and pyrolysis oil through pyrolysis. Thus, this study presents a process for generating high-purity hydrogen (H₂) by catalytically pyrolyzing FNW in a CO₂ environment. The proposed process comprises of three stages: First, the pretreated FNW undergoes Ni/SiO₂ catalytic pyrolysis under CO₂ conditions to produce syngas and pyrolysis oil. Second, the produced pyrolysis oil is incinerated and repurposed as an energy source for the pyrolysis reaction. Lastly, the syngas is transformed into high-purity H₂ via the Water-Gas-Shift (WGS) reaction and Pressure Swing Adsorption (PSA). This study compares the results of the proposed process with those of traditional pyrolysis conducted under N₂ conditions. Simulation results show that pyrolyzing 500 kg/h of FNW produced 2.933 kmol/h of high-purity H₂ under N₂ conditions and 3.605 kmol/h of high-purity H₂ under CO₂ conditions. Furthermore, pyrolysis under CO₂ conditions improved CO production, increasing H₂ output. Additionally, the CO₂ emissions were reduced by 89.8% compared to N₂ conditions due to the capture and utilization of CO₂ released during the process. Therefore, the proposed process under CO₂ conditions can efficiently recycle FNW and generate eco-friendly hydrogen product.

• Korean Journal of Environment and Ecology
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• v.30 no.6
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• pp.1047-1056
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• 2016

This study aims to provide managerial implications for provincial parks through an analysis on visitors' characteristics and motivational factors. The information was collected by surveying 290 visitors. The survey questionnaire consisted of questions regarding visitors' socioeconomic characteristics, characteristics of their travel behavior, visitors' motivation to visit the park, and the degree of satisfaction derived from visiting the park. Results show that most respondents appeared not to collect any information on the park prior to their visit. It was also seen that most visitors do not visit other tourist sites nearby, and are not aware of the Gochang UNESCO biosphere, which indicates that Gochang-gun, which is responsible for park management, needs to make more efforts to promote the park. A factor analysis on the visitors' motivation to visit the park extracted three factors to visit the Seonunsan Provincial Park: 'to hike,' 'to experience and observe nature,' i.e., nature learning field trip and camping, and 'to build and nurture bonding with family and friends.' To examine the effect of these various motivational factors had on the visitors' satisfaction level upon visiting the park, we conducted a multiple regression analysis with the three extracted factors to visit the park and the respondents' socioeconomic characteristics as independent variables, and the degree of recommendation of visiting the park as a dependent variable. The result shows found that, of the three travel factors, only the 'hiking' factor statistically significantly affected the degree of recommendation of visiting the park. This result suggests that the Seonunsan Provincial Park only satisfied hikers and failed to meet the demands for nature experience and observation. It is therefore suggested that the park managers develop new experience-based tourism programs, such as guided tours conducted by professional eco-interpreters.

• Analytical Science and Technology
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• v.31 no.4
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• pp.149-160
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• 2018

A large number of functional living products are being produced for eco-friendly or health-promoting purposes. In the manufacturing process, such products could be adulterated with raw materials with high radioactivity, such as monazite and tourmaline. Thus, it is essential to manage raw materials and products closely related to the public living. For proper management, an accurate radioactivity data of the processed products are needed. Therefore, it is essential to develop a rapid and validated analytical method. In this study, the concentration of the radioactive $^{238}U$ and $^{232}Th$ in building materials (e.g., tile, cement, paint, wall paper, and gypsum board) and living products (e.g., health products, textiles, and minerals) were determined and compared by ED-XRF and ICP-MS. By comparing the results of both methods, we confirmed the applicability of the rapid screening and precise analysis of ED-XRF and ICP-MS. In addition, $^{238}U$ and $^{232}Th$ levels were relatively lower in building materials than in living products. Particularly, $^{232}Th$ content in 6 of 47 living products exceeded (maximum $8.2Bq{\cdot}g^{-1}$) the standard limit of $^{232}Th$ content in raw material ($1.0Bq{\cdot}g^{-1}$).

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.1
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• pp.203-211
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• 2014

Tunnel reduces travel time as and it is essential facilities for the eco-friendly road construction. In recent years, It has been accelerating the tunnel construction to provide a higher level of traffic service but a driver driving in the narrow and dark tunnel takes characteristically psychological anxiety and the restriction of the sight. Moreover, A driver passing through more than 1,000m long tunnel, as to pass inside the monotonous form of the tunnel for a long time can cause drowsiness and increase the driver load. This driver load can degrade road-holding of the inside of the long tunnel highly and pose a high risk of accidents. Accordingly, In this study is to present the proper length of the Tunnel, considering the characteristics of traffic accident. For this, this study is that the long tunnel that affects traffic safety traffic safety variables are selected and classified. Traffic safety variables are classified in detail as a variable of the traffic accident and velocity one, the applicable variables the number of the traffic accident, the ratio of the traffic accident, driving velocity, the individual vehicle velocity etc. Traffic safety variables are categorized as more than a pole length of the tunnel in order to examine its impact on correlation analysis. The results indicate significant results in traffic accidents in accordance with traffic accidents, traffic safety, selects the variable was Variable depending on the length of the tunnel traffic safety point of significantly increasing the possibility of an accident can be seen as a high point. And the point of the Distribution of selected variables in order to create a traffic safety was a significant increase in traffic safety variables was set at critical intervals. Before reaching the critical point and the corresponding length of the long tunnel was set at the proper length. In this study, the optimum length of the proposed long tunnel through the long tunnel that occur in the future to contribute to reducing traffic accidents would be able to be determined.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.1
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• pp.18-24
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• 2018

The policy-making and technological development of eco-friendly automobiles designed to increase their supply is ongoing, but the internal combustion engine still accounts for about 95% of the automobiles in use. Also, in order to meet the stricter emission regulations of internal combustion engines based on fossil fuels, the proportion of after-treatments for vehicles and (ocean going) vessels is gradually increasing. Natural gas is a clean fuel that emits few air pollutants and has been used mainly as a fuel for city buses. In the long term, we intend to develop a new NGOC/LNT+NGCO/SCR combined system that simultaneously reduces the toxic gases, $CH_4$ and NOx, emitted from CNG buses. The objective of this study is to investigate the characteristics of $de-CH_4/NOx$ according to the ceramic and metal substrates of the SCR (Selective Catalytic Reduction) catalysts mounted downstream of the combined system. The V and Cu-SCR catalysts did not affect the $CH_4$ oxidation reaction, the two NGOC/SCR catalysts each coated with two layers began to oxidize $CH_4$ at $400^{\circ}C$, and the amount of $CH_4$ emitted was reduced to about 20% of its initial value at about $550^{\circ}C$. The two NGOC/SCR catalysts each coated with two layers showed a negative (-) NOx conversion rate above $350^{\circ}C$. The ceramic-based combined system reached LOT50 at $500^{\circ}C$, which was about 20% higher in terms of the $CH_4$ conversion rate than the metal-based combined system, showing that the combined system of NGOC/LNT+Cu-SCR is a suitable combination.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.4
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• pp.36-50
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• 2012

This study was carried out to find contradiction factors on laws for children's activity spaces and facilities and to suggest the rational options to control and manage those spaces and facilities by environmental and landscape planning methods. The results of this study are as follows: 1. The major laws related to the environmental safety for children's activity spaces are "Environmental Health Act (ERA)" for managing the environmental safety of children's activity spaces; "Safety Supervision Law of Children's Play Facilities(SSLCPF)" for the inspection and management for safety of children's play facilities; "Quality Management and Industrial Products Safety Management Law(QMIPSML)" for managing safety certification on children's play equipments. 2. The interior space such as "living room" by the Children's Welfare Law(CWL), "Children Park" by the Act on Urban Parks and Green Spaces(AUPGS), "classroom" on private educational institutes by the Act on Establishment and Operation Private Lesson and Training(AEOPLT) and "nursing room" of child care center smaller than $430m^2$ are needed to be managed as an activity space. 3. In order to reduce industrial burden in the production, establishment, construction, and operation and to minimize unwilling extra burden in the administration effort due to legally double regulate, it is necessary to mitigate the inspections on the equipment certificate from QMIPSML and overlapped or different factors and standards must be unified. With this study, the landscape domain could he enlarged from producing, import of play equipment and establishment, construction and operation of play facilities for a comprehensive range of activity spaces, and the landscape industry such as engineering industry, academic research, management, etc.

• Journal of Conservation Science
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• v.27 no.3
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• pp.333-344
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• 2011

Cleaning of foreign matter and corrosion products on surface among conservation treatment of iron artifacts is an important part for looking up a original form. The sand blaster is the most popular equipment when it removes the foreign matter and corrosion products on iron artifacts surface. Current foreign matter and corrosion products equipment, which mostly uses, is sand blaster. Glass dust which sprayed from sand blaster is harmful and causing environmental pollution. In order to solve these problems, we investigated the $CO_2$ snow cleaning that use a eco-friendly equipment to apply for cleaning foreign matter and corrosion products on surface of iron artifacts. It examined by using sand blaster and $CO_2$ snow cleaning to aged steel coupon and iron artifacts. In case of aged steel coupon, the result showed that the sand blaster and $CO_2$ snow cleaning methods were similar to the degrees of cleaning foreign matter and corrosion products, through surface roughness, color measurement and SEM. $CO_2$ snow cleaning applied to aged steel coupons weren't worn out the surface in comparison with sand blaster by SEM. When applied to the iron artifacts, power nozzle of the $CO_2$ snow cleaning was an excellent cleaning effect that surface wern't worn out in comparison with sand blaster. And, it showed that internal structure change of metal was no found before and after cleaning by X-ray radiography. Consequently, we confirmed that cleaning of the sand blaster and power nozzle of $CO_2$ snow cleaning were similar to the effect. But, it's very careful to use this method because of high outlet pressure of power nozzle for applying to the iron artifacts. As a result of experiments, it could be found that the cleaning methods should be selected depending on internal state of the artifacts.

• Korean Journal of Ecology and Environment
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• v.43 no.1
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• pp.44-54
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• 2010

In this study, a comprehensive exploration and evaluation of washland candidate locations by means of field monitoring as well as spatial analysis in six major river system (Han, Nakdong, Nam, Geum, Youngsan, and Seomjin Rivers). Washland(in other words, river detention basin) is an artificial wetland system which is connected to streams or rivers likely to riverine wetlands. Major purpose of washland creation is to control floodings, water supply and purification, providence of eco-cultural space to human and natural populations. Characteristics and functions of riverine wetlands can be expected as well, thus it is believed to be an efficient multi-purpose water body that is artificially created, in terms of hydrology and ecology. Geographical information and field monitoring results for the washland candidate locations were evaluated in 2009, with respect to optimal location exploration, ecosystem connectivity and educational-cultural circumstances. A total of $269\;km^2$ washland candidate locations were found from spatial analysis (main channel of Rivers South Han, 71.5; Nakdong 54.1; Nam, 2.3; Geum, 79.0; Youngsan 46.4; Seomjin 15.7), and they tended to be distributed in mid- to lower part of the rivers to which tributaries are confluent. Field monitoring at 106 sites revealed that some sites located in the Rivers Nam and Geum is appropriate for restoration or artificial creation as riverine wetlands. Several sites in the Nakdong and Seomjin Rivers were close to riverine wetlands (e.g., Upo), habitats of endangered species (e.g., otters), or adjacent to educational facility (e.g., museums) or cultural heritages (e.g., temples). Those sites can be utilized in hydrological, ecological, educational, and cultural ways when evidence of detailed hydrological evaluation is provided. In conclusion, determination of washland locations in the major river basins has to consider habitat expansion as well as hydrological function (i.e. flood control) basically, and further utility (e.g. educational function) will increase the values of washland establishment.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.4
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• pp.395-407
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• 2002

A 3D hydrodynamic-ecological coupled model was applied to estimate a food supply to oysters in Geoje-Hansan Bay where is one of the oyster culturing sites in Korea, In this study, the primary productivity (PP) was adopted as an index of food supply, and the spatial patterns of average chlorophyll a concentration during a culturing seasons from September to May of the following year were simulated by the model, The numerical result showed that PP was high in the inner part of the bay and the adjacent areas of Hwado island, but low in the outer. This result indicates that PP is essentially influenced by anthropogenic nutrient loadings in the system. The model was calibrated using the field data in May which is non culturing season of oysters and a simulated phytoplankton biomass agreed fairly well with the observed data ($R^{2}=0.70$, $RE=10.3\%$). The computed food supply varied from 0.19 to $1.27\;gC/m^{2}/day$ with a mean value of $0.62 gC/m^{2}/day$ from September to May. The highest value was showed in May ($1.27 gC/m^{2}/day$) and the lowest was in February ($0.19 gC/m^{2}/day$).

• Management & Information Systems Review
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• v.31 no.4
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• pp.559-592
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• 2012

In spite of the transitional changes in the shoe industry in Busan area, regular academic studies on the management plan to improve the practical competitiveness of footwear industry focused in the materials, bio-dynamics, components, and designs, etc. in the engineering viewpoint are very rare. Many reports of policies were published from late 190's to 2000's but they were limited to the identification of practical situations and the measures for strategic alternatives and were not developed to be the academic studies to improve the competitiveness in terms of management control. It is intended to seek for the measures to be reviewed as the alternatives to improve the self-competitiveness of footwear companies by approaching the problems limited to such specific area in the viewpoint of management control. The core of this study is to provide the alternative plans for expansion of the industrial foundation by seeking for the measures to improve competitiveness with application of knowledge management as an alternative for improvement of not transient but sustainable industrial competitiveness, in order to help the export of shoes from Busan area which has been rapidly increased since the Korea-USA FTA and Korea-EU FTA. In such viewpoint, in the study, a questionnaire survey was performed related with the issues of Busan's footwear industry and the plan to implement knowledge management was discussed for improvement of the competitiveness of footwear industry based on the result of such questionnaire survey. As most of studies and directions have been focused in functional shoes, designs, materials, and components, etc., which are related with the properties of human dynamics, as the alternatives for improvement of the footwear industry of Busan area and did not suggest the measures to make basic changes in the management of companies, the implementation of knowledge management was emphasized in order to seek for the direction of such plan. The purpose of this study is to suggest an alternative for construction of industrial eco-system for high added value by seeking for the probability of knowledge management for conversion of footwear industry into knowledge industry. In order to accomplish the effect of increased export as the result of FTA, current management method of footwear companies is limited and the effect of FTA should be maximized by improving the competitiveness with implementation of knowledge management methods. Settlement of such knowledge management will act as the momentum to improve the competitiveness of footwear companies and, in a long-term viewpoint, will be able to maximize the improvement of knowledge industry and creation of job opportunities.