• Applied Chemistry for Engineering
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• v.31 no.2
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• pp.115-124
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• 2020

Sustainable plastics can be mainly categorized into (1) biodegradable plastics decomposed into water and carbon dioxide after use, and (2) biomass-derived plastics possessing the carbon neutrality by utilizing raw materials converted from atmospheric carbon dioxide to biomass. Recently, biomass-derived engineering plastics (EP) and natural nanofiber-reinforced nanocomposites are emerging as a new direction of the industry. In addition to the eco-friendliness of natural resources, these materials are competitive over petroleum-based plastics in the high value-added plastics market. Polyesters and polycarbonates synthesized from isosorbide and 2,5-furandicarboxylic acid, which are representative biomass-derived monomers, are at the forefront of industrialization due to their higher transparency, mechanical properties, thermal stability, and gas barrier properties. Moreover, isosorbide has potential to be applied to super EP material with continuous service temperature over 150 ℃. In situ polymerization utilizing surface hydrophilicity and multi-functionality of natural nanofibers such as nanocellulose and nanochitin achieves remarkable improvements of mechanical properties with the minimal dose of nanofillers. Biomass-derived tough-plastics covered in this review are expected to replace petroleum-based plastics by satisfying the carbon neutrality required by the environment, the high functionality by the consumer, and the accessibility by the industry.

• Journal of Bio-Environment Control
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• v.31 no.4
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• pp.423-431
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• 2022

Due to increase of interest in 'carbon neutrality', attempts at agricultural use of CO₂ are increasing. In this study, we used the dry-ice made by CO₂ as by-product in thermoelectric power plant on CO₂ fertilization for production of leafy vegetable in greenhouses. The dry-ice was supplied on three leafy vegetable farms (Allium tuberosum Rottl. ex Spreng, Aster scaber, and Oenanthe stolonifera DC.) located in Hadong, Gyeongsangnamdo. Two greenhouses were used in each leaf vegetable crops, one greenhouse used as the control (non-treatment), other greenhouse used as supplied CO₂. For CO₂ fertilization, a gas sublimated from dry ice was supplied to the greenhouse using a specially designed prototype supply machine. A. tuberosum greenhouse has no difference of CO₂ concentration between the control, and CO₂ fertilization and shown high CO₂ concentration both greenhouses. However, the CO₂ concentrations in A. scaber and O. stolonifera greenhouses were increased in CO₂ fertilization treatment. The growth of A. scaber and O. stolonifera were increased in CO₂ fertilization, and the yield also increased to 36% and 25% than the control, respectively. As a result of economic analysis, the A. scaber has increase of income rate, however A. tuberosum and O. stolonifera has decreased income rate. Thus, the use of the dry-ice made by CO₂ as by-product in thermoelectric power plant has possibility to increase productivity of the leafy vegetable in greenhouse and have agricultural use value.

• Journal of Science of Art and Design
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• v.1
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• pp.63-93
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• 1999

This treatise begins with finding a meaning of Paul Klee's . It is pretty simpleto choose the square of Klee. The most important formative language for twenty century is abstraction. The element of speaking for abstraction issquare. The artists are trying to contain the nature and universe in the square. The role of magic square consisting with small squares of Klee is crystallized. The other side, the test of this study is a method analysis. The method analysis is changing while concept and style have been changing according to a period. The existing method analysis is an iconology used many times in Art history. This treatise introduces France symbolists, Bernard Cocula and Claude Peyroutet's analysis of a meaning of image(Semantique do l'image) who were applied to Modern Art. based on Iconography. It also applies to analysis of artwork of Klee. Cocula's is developed from one phase to five phase step by step. The first phase deals with an appearance of artwork. Subsequently, the second phase is directly adjacent to personal feeling and impression. This is an adequate method for image study in the analysis of modern arts. This phase makes it a rule to enjoy talking with artworks above all. The third phase begins with this question 'What do you see? (que voyons-nous?).' The applies exhaustively and strictly to complicated image artworks which need an elaborate analysis. It is very hard but audiences must try to maintain neutrality in front of artwork because cord formation and interpretation should be formed objectively. The meaning analysis and interpretation of the forth phase begins with this question 'what is the image rouse'(qu'evoque cote image?).' This phase is the most important in a process of symbolic analysis. The audience investigates personal elements and common elements. The fifth is synthetic analysis and interpretation phase. The synthesis is last phase and it reaches a valuation and a conclusion. Namely, the synthesis phase makes up synthesis conclusion, summarizes image character, and completes value adjudication. Sometimes it completes no conclusions in a silence. This study found a new possible analysis example from Paul Klee's work. The study emphasizes square analysis and interpretation and uses . The analysis of artwork by Cocula's is an example of the most important work of Klee's three artworks. The first analysis of artwork is and the second one is . The third one is . In these analyses, Klee usedmagic square 'to make natural pictorial element and to explain organic living things.'

• Journal of Hospice and Palliative Care
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• v.20 no.2
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• pp.100-110
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• 2017

Purpose: We explored Koreans' perception of the meaning of death with dignity that Korean people. Methods: A phenomenological research methodology was applied. A total of 13 participants were sampled based on their age and gender. Participants were interviewed in depth from September 2015 through February 2016. Colaizzi's phenomenological analysis method was used for data analysis. To establish the validity of the study, we evaluated its realistic value, applicability, consistency and neutrality of the qualitative evaluation criteria of Lincoln and Guba. Results: Koreans' perception of death with dignity was structured as 19 themes, nine theme clusters and four categories. The four categories were "comfortable death", "good death", "resolving problems before death", and "death with good reputation". The theme clusters were "death without pain", "death submitting to one's fate", "death that is not ugly", "leaving good memories to others", "dying in a way we want", "death after proper settling of things", "dealing with chronic resentment before death", "death after living a good life", and "death with recognition". Conclusion: For Koreans, death with dignity meant not burdening others, settling things right and leaving good memories to their families and friends. Such perceptions can be applied to hospice care for terminally ill patients.

• Journal of IKEEE
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• v.25 no.2
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• pp.267-272
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• 2021

Recently, attention has been focused on renewable energy and carbon neutrality to resolve fossil energy depletion and environmental problems. In addition, high-rise urban buildings and an increase in building energy are rapidly increasing. There are many restrictions on installing solar power in urban areas. In addition, as buildings become taller, a lot of low-light environments in which shade is formed occur. Therefore, in this study, we intend to develop a power plant capable of generating electric power in an outdoor low-light environment and indoor lighting environment. The power plant in a low-light environment used a dye-sensitized solar cell. A unit cell and a 20cm×20cm module were manufactured, and the electrical characteristics of the power plant were measured using light sources of LED, halogen lamp, and 3-wavelength lamp. The photoelectric conversion efficiency of the unit cell was 17.2%, 1.28%, 19,2% for each LED, halogen lamp, and 3-wavelength lamp, and the photoelectric conversion efficiency of the 20cm×20cm module was 10.9%, 8.7%, and 11.8%, respectively. In addition, the maximum power value of the module was 13.1mW, 15.7 mW, and 14.2 mW for each light source, respectively, confirming the possibility of power generation in a low-light environment

• Journal of Korean Society of Disaster and Security
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• v.15 no.1
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• pp.47-56
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• 2022

Recently, water resources and energy policies such as integrated water management and carbon neutrality are changing rapidly. There is an opinion that the value of hydropower reservoirs related to these policies should be re-evaluated. In the past, they have contributed to flood control in addition to electricity generation, such as operating at a limited water level during the flood season, but loss of power generation is inevitable with this operation. Therefore, this study introduced the concept of resilience to the hydropower generation system to minimize the power loss. A framework for evaluating the power generation performance of them was presented by defining the maximization of electricity sales as performance. Based on the current procedure of multiple operation plan, a scenario was established and simulation was performed using HEC-5. As a result of applying to the framework, it was confirmed that the power generation performance according to each scenario was evaluated as an important factor. And it was confirmed that the performance of flood control and water use could also be evaluated.

• Clean Technology
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• v.28 no.2
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• pp.163-173
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• 2022

Research and development of biofuels as one of the means to mitigate global warming and to avoid fossil fuel depletion has occurred for more than 30 years. However, there has only been limited distribution of a few first- and second-generation biofuels, and widespread supply and consumption of biofuels is still far from a reality. Although a relatively recently studied third-generation biofuel derived from seaweed biomass has been shown to have many advantages, it is yet to be deployed in commercial-scale seaweed biorefineries. This review paper examines the advantages and disadvantages of seaweed biorefineries for the entire value chain covering from seaweed and its cultivation to biofuel production based on an extensive literature search and the author's experience of conducting feasibility studies pertaining to seaweed biorefineries for over 10 years. For this purpose, the literature survey will cover the current status of seaweed production and its research and development worldwide, conversion technologies for biofuel production from seaweed based on bench-scale experiments, and large-scale techno-economic feasibility studies for seaweed conversion to biofuels and bioenergy. In addition, the main problems expected with the commercialization of seaweed-based biofuels will be identified. Finally, the current status of seaweed biorefinery technology and the author's views on its promising future will be summarized.

• Korean Journal of Remote Sensing
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• v.39 no.6_3
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• pp.1721-1730
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• 2023

As awareness of the problem of global warming emerges around the world, the role of carbon sinks in settlement is increasingly emphasized to achieve carbon neutrality in urban areas. In order to manage carbon sinks in settlement, it is necessary to identify the current status of carbon sinks. Identifying the status of carbon sinks requires a lot of manpower and time and a corresponding budget. Therefore, in this study, a map predicting the location of trees was created using already established tree location information and Sentinel-2 satellite images targeting Seoul. To this end, after constructing a tree presence/absence dataset, structured data was generated using 16 types of vegetation indices information constructed from satellite images. After learning this by applying the Extreme Gradient Boosting (XGBoost) model, a tree prediction map was created. Afterward, the correlation between independent and dependent variables was investigated in model learning using the Shapely value of Shapley Additive exPlanations(SHAP). A comparative analysis was performed between maps produced for local parts of Seoul and sub-categorized land cover maps. In the case of the tree prediction model produced in this study, it was confirmed that even hard-to-detect street trees around the main street were predicted as trees.

• Journal of the Korean Institute of Landscape Architecture
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• v.52 no.3
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• pp.103-113
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• 2024

This study is based on the design project of 'Sun-Garden' within the Solaseado Solar Power Plant located in Solaseado, which is a New City being developed in Haenam, Jeollanam-do. The purpose of this study is to create an integrated and sustainable energyscape that harmonizes energy infrastructure with the natural environment, while supporting the city's carbon neutrality agenda. To achieve this, design principles were established by considering three key aspects. The first aspect is economic, which seeks to create multifunctional spaces that integrate nature and technology, pursuing long-term sustainability while generating additional economic value. The second aspect is natural, emphasizing the creation of planting environments that conserve and enhance ecosystems, introduce region-specific species, and maintain ecosystem services and sustainable resource use. The third aspect is landscape, offering sensory and educational experiences to visitors and functioning as a landmark that symbolizes the carbon-neutral garden city of Solaseado through the aesthetic harmony of nature and technology. Through the creation of the 'Sun-Garden,' the Solaseado Solar Power Plant exemplifies a sustainable energyscape development model that merges economic, environmental, and landscape aspects beyond the conventional energy production facility. This project is expected to provide guidelines and implications for future energy infrastructure design, contributing to global energy transition efforts.

• Resources Recycling
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• v.33 no.2
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• pp.62-72
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• 2024

Although the Paris Agreement in 2015 aimed to limit global temperature increases to below 2℃ and eventually to 1.5℃ to address the climate crisis, global temperature continues to rise. Developed countries have proposed a circular economy as a major strategy to tackle this issue. Detailed implementation methods include reusing, remanufacturing, recycling, and energy recovery. Remanufacturing has a greater potential to achieve high added value and carbon neutrality than other resource circulation methods. However, currently, no standardized method for quantitatively evaluating the greenhouse gas (GHG) reduction effects of remanufacturing exists. This study compares and analyzes recent research trends since 2020 on the calculation of GHG emission reduction effects from remanufacturing. It also examines international standards for environmental impact assessment, including GHGs and environmental performance labeling systems. This study derives the key factors for standardizing the calculation of the GHG emission reduction effects of remanufactured products.