• Journal of the Korean Recycled Construction Resources Institute
• /
• v.6 no.4
• /
• pp.324-330
• /
• 2018

In accordance with the amendment of the Industrial Safety and Health Act of 2007, Korea completely prohibited the import, distribution and manufacture of asbestos like Europe and Japan. Accordingly, the current problem of asbestos is the safe maintenance and disposal of asbestos construction material, the disposal of asbestos, and the final disposal of asbestos building materials. In the past, Korea used 100,000 tons of asbestos every year, and the building materials using it exceeded 1 million tons per year. These asbestos building materials continued to be used until 2006, and the Ministry predicted that these materials would continue to be maintained until 2044. When the permeable hardening agent is applied to the asbestos building material installed in the pre-pretreatment step for the harmless treatment of the asbestos waste and the dismantling is carried out, the scattering of the asbestos is suppressed in the disassembling step, detoxification treatment conditions can be improved. Therefore, permeable hardeners should be stably penetrated into asbestos building materials. In this study, it is suggested that pre - pretreatment methods for the harmlessization of waste asbestos building materials with medium density level can be presented. In order to efficiently perform pre - treatment for chemical harmlessness in the future, the mixing ratio of permeable hardener and middle water Optimization is the most important factor.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.20 no.2
• /
• pp.622-631
• /
• 2019

The purpose of this study is to establish and apply a public transport valuation system to form required policy for institutionalization. Over the past six years, Jeju has seen a steady increase in the number of cars owned by its population. Also, as the number of tourists has changed from group to individual tourists, the rate of rental car use has increased rapidly. As a result, road congestion in Jeju city is becoming as crowded as Seoul., Jeju Island is said to have created a foundation for faster, more convenient, and cheaper use of transportation through the reorganization of the public transportation system in August 2017. This is also reflected in the Public Transportation Value Assessment. Jeju residents were in favor of strengthening public transportation priority policy. In addition, public transport valuations are highly valued in the order of public transportation fares, public transportation stability, public transportation policies for the common people, public transportation policies for the vulnerable, public transportation policies for residents, environmentally-friendly policies, and public transportation to help ease traffic congestion. This is because public transportation has a wide range of values and should refine the factors that local governments use to evaluate policy. These methods need to be institutionalized and actively utilized through the establishment of a value assessment system for public transport.

• Membrane Journal
• /
• v.30 no.6
• /
• pp.395-408
• /
• 2020

Polymer electrolyte membrane fuel cells (PEMFCs) have gained much attention as eco-friendly energy conversion devices without emission of environmental pollutant. Polymer electrolyte membrane (PEM) that can transfer proton from anode to cathode and also prevent fuel cross-over has been regarded as a key component of PEMFCs. Although perfluorinated polymer membranes such as Nafion® were already commercialized in PEMFCs, their high cost and toxic byproduct generated by degradation have still limited the wide spread of PEMFCs. To overcome these issues, development of hydrocarbon based PEMs have been studied. Incorporation of cross-linked structure into the hydrocarbon based PEM system has been reported to fabricate the PEMs showing both high proton conductivity and outstanding physicochemical stability. This study focused on the various cross-linking strategies to the preparation of cross-linked PEMs based on hydrocarbon polymers with ion conducting groups for application in PEMFCs.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.12
• /
• pp.731-741
• /
• 2020

University campus plans include urban and spatial values and identities that they emphasize. The purpose of this study is to analyze sustainable campus policy, space, and the application to architectural planning, which UBC in Canada pursues independently from a Green Campus Certificate System. Sustainable directions and architectural components are deduced. The results are as follows: 1) the correspondence between the campus plan's goal and architectural implementation is the most important. Thus, the university must build a system for the plan's goal and a strategy to make a sustainable campus. 2) A guideline and system are requested to make many experts in various fields and stakeholders participate in the initial stage through "Design Charrette." 3) A system of virtuous circulation must be built so that feedback can be applied through the real-time comparison and verification of building energy consumption. Another goal of this study is emphasizing the necessity of campus policy and plans based on the "Living Laboratory" concept to make a sustainable city. This study could be meaningful because it supports a basis for triggering the establishment of goals for a sustainable plan and implementation in Korean universities.

• Clean Technology
• /
• v.27 no.1
• /
• pp.85-92
• /
• 2021

A solar water battery is a system that generates power using solar energy. It is a combination of photoelectrochemical cells and an energy storage system. It can simultaneously convert and store solar energy without additional external voltage. Solar water batteries consist of photoelectrodes, storage electrodes and counter electrodes, and their properties and combination are important for the performance and the efficiency of the system. In this study, we tried to find the effect that changing the components of solar water batteries has on its system. The effects of the counter electrode during discharge, the kinds of photoelectrode and storage electrode materials, and electrolytes on the solar energy conversion and storage capacitance were studied. The optimized composition (TiO2 : NaFe-PB : Pt foil) exhibited 72.393 mAh g-1 of discharge capacity after 15 h of photocharging. It indicates that the efficiency of solar energy conversion and storage is largely affected by the configuration of the system. Also, the addition of organic pollutants to the chamber of the photoelectrode improved the battery's photo-current and discharge capacity by efficient photoelectron-hole pair separation with simultaneous degradation of organic pollutants. Solar water batteries are a new eco-friendly solar energy conversion and storage system that does not require additional external voltages. It is also expected to be used for water treatment that utilizes solar energy.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.28 no.1
• /
• pp.141-152
• /
• 2022

As interest increases related to the development of eco-friendly energy, the offshore wind turbine market is growing at an increasing rate every year. In line with this, the demand for an installation vessel with large scaled capacity is also increasing rapidly. The wind turbine installation vessel (WTIV) is a fixed penetration of the spudcan in the sea-bed to install the wind turbine. At this time, a review of the spudcan is an important issue regarding structural safety in the entire structure system. In the study, we analyzed the current procedure suggested by classification of societies and new procedures reflect the new loading scenarios based on reasonable operating conditions; which is also verified through FE-analysis. The current procedure shows that the maximum stress is less than the allowable criteria because it does not consider the effect of the sea-bed slope, the leg bending moment, and the spudcan shape. However, results of some load conditions as defined by the new procedure confirm that it is necessary to reinforce the structure to required levels under actual pre-load conditions. Therefore, the new procedure considers additional actual operating conditions and the possible problems were verified through detailed FE-analysis.

• Journal of Cadastre & Land InformatiX
• /
• v.51 no.2
• /
• pp.83-106
• /
• 2021

Interests in clean fuels have been soaring because of environmental problems such as air pollution and global warming. Unlike fossil fuels, hydrogen obtains public attention as a eco-friendly energy source because it releases only water when burned. Various policy efforts have been made to establish a hydrogen based transportation network. The station that supplies hydrogen to hydrogen-powered trucks is essential for building the hydrogen based logistics system. Thus, determining the optimal location of refueling stations is an important topic in the network. Although previous studies have mostly applied optimization based methodologies, this paper adopts machine learning to review spatial attributes of candidate locations in selecting the optimal position of the refueling stations. Machine learning shows outstanding performance in various fields. However, it has not yet applied to an optimal location selection problem of hydrogen refueling stations. Therefore, several machine learning models are applied and compared in performance by setting variables relevant to the location of highway rest areas and random points on a highway. The results show that Random Forest model is superior in terms of F1-score. We believe that this work can be a starting point to utilize machine learning based methods as the preliminary review for the optimal sites of the stations before the optimization applies.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.27 no.7
• /
• pp.1098-1105
• /
• 2021

The International Maritime Organization has steadily strengthened environmental regulations on nitrogen oxides and carbon dioxide emitted from marine vessels. Consequently, the demand for electric propulsion vessels based on eco-friendly elements has increased. To this end, research and development has been steadily conducted for various vessels. In electric propulsion systems, a redundancy configuration is typically adopted to increase reliability and facilitate the onboard arrangement. Furthermore, studies have been actively conducted to ensure the safety of electric propulsion systems through the combination with digital twin technology. A digital twin can be used to predict outcomes in advance by implementing real-world equipment or space in a virtual world like twins, integrating real-world information and data with the virtual world, and performing computer simulations of situations that can occur in a real environment. In this study, we perform failure modes and effects analysis (FMEA) to validate the electric power management system (PMS) redundancy scheme for the digital twin technology development of electric propulsion vessels. Then, we propose the role and algorithm of PMS as a compensation function for preventing primary and secondary damages caused by a single equipment failure of the PMS and preventing additional damages by analyzing the impact on the entire system under real vessel operating conditions based on the redundancy FMEA suggested for the ship classification and certification. We verified the improvement in propulsion conservation through tests.

• Korean Chemical Engineering Research
• /
• v.61 no.3
• /
• pp.456-462
• /
• 2023

An electrically conductive and transparent electrode was created by applying a dispersion of pristine single-walled carbon nanotubes (SWCNTs) and silver nanowires to a polyethylene terephthalate (PET) film using a bar coating method. The SWCNTs were added to increase the electrical conductivity and transmittance of the silver nanowires while also preventing the haze from increasing due to the stacking of multiple layers containing SWCNTs and silver nanowires on the PET substrate. The silver nanowires in the electrode were also found to be stable against oxidation. The transparent electrode displayed excellent electrical and optical properties, with a sheet resistance of 47 Ω/□, transmittance of 96.72%, and haze of 1.93%. Additionally, the sheet resistance of the electrode remained stable over time, with a change of only 6.4% after a constant temperature and humidity test, making it suitable for long-term use. A hybrid transparent electrode that is economically feasible and environmentally sustainable has been developed through the utilization of pristine SWCNT and silver nanowire.

• The Journal of the Convergence on Culture Technology
• /
• v.10 no.1
• /
• pp.379-386
• /
• 2024

The purpose of this study was to pay attention to the increase in the frequency of expression of butterflies and insects, whose decrease in the number of individuals is symbolized as a measure of environmental pollution, among the various motifs of nature as we go through the COVID-19, when we realized the importance of nature. The scope of this study was limited to fashion collection fashion show photos and interview articles of online for fashion collections from 2019 to 2023. As a result of the study, 185 butterfly motivation fashion design appeared, and digital printing techniques were the most used as a type of plane expression method. Along with this, techniques such as quilting, embroidery, and beading have appeared a lot as techniques to express the planar motif of butterflies. As for the three-dimensional expression types, 3D printing, laser cutting, corsage techniques, and draping techniques showed similar proportion. It can be seen that the expressed butterfly motif had more realistic description the shape of the butterfly as it was than abstract expressions. In conclusion, it can be seen that the butterfly motif fashion design over the past five years contains a stronger message about the environment than the butterfly motif fashion in the past. It was confirmed that it is a motif with a great symbolic meaning that can convey an eco-friendly message beyond just the morphological beauty and colorful design elements of the butterfly.