• Journal of Navigation and Port Research
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• v.45 no.3
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• pp.130-137
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• 2021

The main purpose of this study is to provide an objective evaluation standard for the assessment of marine spatial characteristics via Ulsan floating offshore wind power project using HEA.. Various levels of damage occur in the waters (5,017.6) near the floating offshore wind power terminals in Ulsan, including commercial damage, ecological destruction and reduction in quality of life due to seascape damage. Alternative restoration projects for calculating the economic value of damage were selected including artificial reef projects and estimates based on HEA. For basic households with a 4.5% social discount rate and a 100% maturity index over four years, the damage was approximately 457 hundred million won. The HEA in this study resolves the possible irrationality in the evaluation of marine spatial characteristics, since the value is calculated based on objective and clear DATA. Therefore, the study results are intended to facilitate conflict resolution between stakeholders in the future during the implementation of the marine spatial plan.

• Clean Technology
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• v.27 no.3
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• pp.269-274
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• 2021

Bioenergy is generally considered to be one of the options for pursuing carbon neutrality. However, for a period of time, combustion of harvested plant biomass inevitably causes more carbon dioxide in the atmosphere than combustion of fossil fuels. This paper proposes a method that predicts and minimizes the total amount and payback period of this carbon debt. As a case study, a carbon cycle impact assessment was performed for immediate switching of the currently used fossil fuels to biomass. This work points out a fundamental vulnerability in the concept of carbon neutrality. As an action plan for the sustainability of bioenergy, formulas for afforestation proportional to the decrease in the forest area and surplus harvest proportional to the increase in the forest mass are proposed. The results of optimization indicate that the carbon debt payback period is about 70 years, and the carbon dioxide in the atmosphere increases by more than 50% at a maximum and 3% at a steady state. These are theoretically predicted best results, which are expected to be worse in reality. Therefore, biomass is not truly carbon neutral, and it is inappropriate as an energy source alternative to fossil fuels. The method proposed in this work is expected to be able to contribute to the approach to carbon neutrality by minimizing present and future carbon debt of the bioenergy that is already in use.

• Korean Journal of Environment and Ecology
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• v.35 no.2
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• pp.193-203
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• 2021

As endangered species are gradually increasing due to land development by humans, it is essential to secure sufficient protected areas (PAs) proactively. Therefore, this study checked priority conservation areas to select candidate PAs when considering the impact of land development. We determined the conservation priorities by analyzing four scenarios based on existing conservation areas and reflecting the development impact using MARXAN, the decision-making support software for the conservation plan. The development impact was derived using the developed area ratio, population density, road network system, and traffic volume. The conservation areas of endangered species were derived using the data of the appearance points of birds, mammals, and herptiles from the 3rd National Ecosystem Survey. These two factors were used as input data to map conservation priority areas with the machine learning-based optimization methodology. The result identified many non-PAs areas that were expected to play an important role conserving endangered species. When considering the land development impact, it was found that the areas with priority for conservation were fragmented. Even when both the development impact and existing PAs were considered, the priority was higher in areas from the current PAs because many road developments had already been completed around the current PAs. Therefore, it is necessary to consider areas other than the current PAs to protect endangered species and seek alternative measures to fragmented conservation priority areas.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.3
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• pp.36-43
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• 2021

Because bridges are major national infrastructure, regular safety inspections or diagnoses for bridges have been conducted in accordance with the "Special Act on the Safety and Maintenance of Facilities." Accordingly, the condition and safety assessments of the bridge are conducted to derive the condition and safety rating, respectively. A lower result is determined to be the safety grade of the bridge. In this study, the relationship between the condition rating and safety rating, which are the core of the bridge safety grade, was analyzed by the representative superstructure types of bridges, such as RC slab, PSCI girder, Steel box girder, Rhamen, and Preflex girder, to identify the correlation status and range between each rating. A reasonable improvement direction for establishing existing maintenance policies was suggested by proposing an alternative plan to change the proper implementation cycle of the inspection and diagnosis of bridge superstructure types. As a result of the research, it is necessary to adjust the inspection and diagnosis cycle according to the superstructure type and safety grade. In addition, maintenance policies need to be improved through detailed research on more diverse bridge types in the future.

• Korean Journal of Construction Engineering and Management
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• v.22 no.4
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• pp.3-10
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• 2021

According to the IPCC, humans are influencing the climate system. Such changes in the climate system can cause problems in the supply of food ingredients in the agricultural field by changing the existing growing environment. To solve this problem, vertical farms can be a good alternative for a stable supply of food ingredients. Although the vertical smart farm pays close attention to maintaining and managing the growing environment of crops, it is difficult to uniformly implement temperature, humidity, illumination, oxygen, and carbon dioxide concentrations in the building space. As a result of conducting computational fluid dynamics analysis to ensure air uniformity, a remarkable result is that it is advantageous to continuously spray suitable carbon dioxide CO2 concentrations for a long period of time for air uniformity in a vertical smart farm. Through this result, it is possible to efficiently plan a growing environment system optimized for a vertical smart farm. Based on this study, if efficient crops are produced by creating an optimized growing environment for vertical smart farms, it will be able to contribute to the development of the agricultural field.

• Journal of Korean Society of Disaster and Security
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• v.14 no.1
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• pp.61-72
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• 2021

There is an increasing need for water supply plan using sustainable groundwater to resolve water shortage problem caused by drought due to climate change and artificial aquifer recharge has recently emerged as an alternative. This study deals with recharge potential assessment for artificial recharge system and quantitative assessment for securing stable water and efficient agricultural water supply adapt to drought finding optimal operating condition by numerical modeling to reflect recharge scenarios considering climate condition, target water intake, injection rate, and injection duration. In order to assess recharge potential of injection well, numerical simulation was performed to predict groundwater level changes in injection and observation well respect to injection scenarios (Case 1~4) for a given total injection rate (10,000 m³). The results indicate that groundwater levels for each case are maintained for 25~42 days and optimal injection rate is 50 m³/day for Case 3 resulted in groundwater level rise less than 1 m below surface. The results also show that influential area of groundwater level rise due to injection was estimated at 113.5 m and groundwater storage and elapsed time were respectively increased by 6 times and 4 times after installation of low permeable barrier. The proposed assessment method can be contributed to sustainable agricultural water supply and stable water security for drought adaptation.

• The Journal of the Korea Contents Association
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• v.21 no.1
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• pp.511-519
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• 2021

This study examined the perception of life felt by low-income people in middle-aged and elderly people by enhancing the population structure of Korea, which is entering an aging society. For the analysis, the variables that need from the 2019 welfare panel data provided by the Ministry of Health and Welfare were selected. The final 1,684 samples were selected from the panel samples of 14,918 people, from the '60-70s' of 'low income class', by removing the unresponsive and insincere samples. In particular, this study defined as a dependent variable as a 'ladder of life' measured in panel data, and analyzed the personal characteristics and life satisfaction factors affecting 'ladder of life'. As a result of the analysis, most of the personal characteristics were found to be influential factors of the "ladder of life" when considering only personal characteristics as an influential factor for the dependent variable "ladder of life". Also, as a result of examining the interaction effect on the economic state variable, there was no significant interaction effect. This shows that the health condition is more important than the economic condition as the influential factor on the ladder of middle-aged elderly people. Therefore, the recognition of the elderly 'ladder of life' should improve the awareness of the elderly's life by various 'environmental factors', both internal and external, rather than the personal conditions and environment of the elderly. In other words, a plan to present a positive alternative to their perception of life will be needed.

• Food Science and Industry
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• v.55 no.2
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• pp.128-139
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• 2022

Although edible insects are attracting attention as future alternative food because of their nutritional, eco-friendly, and economic advantages and functionality, consumption is low, so measures to promote consumption are needed. The problems in edible insect consumption were identified as the aversion to the edible insects, lack of publicity for edible insects newly registered in the Food Code, and difficulties in continuously supplying high-quality edible insects and selling products. To solve these problems, it is necessary to establish effective public relations plans for new edible insects and develop processing methods for improving their taste and flavor, education content about edible insects, and products interesting to the target age. In addition, it is necessary to establish a one-stop cluster that can perform quality control of harmful substances and nutrients, purchase raw materials, sell products, educate, and publicize.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.4
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• pp.648-656
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• 2022

As environmental regulations such as the International Maritime Organization (IMO)'s strategy to reduce greenhouse gases(GHG) are strengthened, technology development such as eco-friendly ships and alternative fuels is expanding. As part of this, ship propulsion technology using energy reduction and wind propulsion technology is emerging, especially in shipping companies and shipbuilders. By securing wind propulsion technology and introducing empirical research into shipbuilding and shipping, a high value-added market using eco-friendly technology can be created. Moreover, by reducing the fuel consumption rate of operating ships, GHG can be reduced by 6-8%. Rotor Sail (RS) technology is to generate a hydrodynamic lift in the vertical direction of the cylinder when the circular cylinder rotates at a constant speed and passes through the fluid. This is called the Magnus effect, and this study attempted to propose a plan to increase propulsion efficiency through a numerical analysis study on turbulence flow characteristics around RS, a wind power assistance propulsion system installed on a ship. Therefore, C_L and C_D values according to SR and AR changes were derived as parameters that affect the aerodynamic force of the RS, and the flow characteristics around the rotor sail were compared according to EP application.

• The Journal of the Korea Contents Association
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• v.22 no.10
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• pp.445-459
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• 2022

This study presented a plan to improve the life satisfaction and leisure status of the elderly in the With COVID-19 era, and the life satisfaction of the elderly. For this purpose, we investigated life satisfaction and leisure life for 107 senior citizens at the Gyeonggi Senior Welfare Center, and the following results were obtained. First, it can be seen that overall life satisfaction was relatively lower after Corona than before. Second, in the correlation between leisure activity and life satisfaction, there was no significant correlation between the level of leisure activity and life satisfaction before Corona, and a significant positive correlation was found between the level of leisure activity and life satisfaction after Corona. seemed If alternative measures are proposed according to these results, first, it is necessary to seek ways to improve and manage the environment for the elderly in the with Corona era in the local community. In particular, in order to reduce the adaptation gap among the elderly due to the many changes in digital technology, institutions related to the elderly are providing education on how to use smartphones and kiosks, but it needs to be expanded as a community-wide measure. Second, a systematic system for health care for the elderly in the era of With Corona must be provided. Third, the old-age income security system and support are required so that the minimum living security is guaranteed for the elderly who are experiencing economic difficulties due to the corona virus. Fourth, it is necessary to revitalize programs related to talking to the elderly and counseling for the improvement of relationships and location satisfaction due to social distance and relationship atrophy due to Corona.