• International Journal of Highway Engineering
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• v.19 no.6
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• pp.57-66
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• 2017

PURPOSES : This study develops eco-friendly asphalt reinforcement materials applicable to bridge deck pavement. The main purpose is to ensure highly reliable quality applicable to structures and the possibility of practical application. The main target of the study is to develop materials that are environmentally friendly and capable of improving performance. METHODS : The application of double-reinforcement fiber improves the performance of the road pavement. 1. We use recycled film for application of sheet-typed reinforcement. 2. We use preprocessing fibers to reinforce the properties of composite pavement materials. RESULTS : The developed products may produce materials that fit the purpose of achieving stability and environmental friendliness. Sheet-typed reinforcements use more than 50% recycled resin. The most important type of damage to the asphalt layer is deflection (plastic deformation). These products have a very high deflection resistance of not less than 6,000 cycles/mm. In addition, all performance is excellent. Thus, it will be easier to access the field in the future. CONCLUSIONS : Fiber-reinforced asphalt pavement showed excellent performance. Sheet-typed reinforcements containing 50% recycling resin produced good performance in terms of functionality as well as environmental friendliness. Thus, enhancing the field applicability will enhance the usability of the reinforcements.

• Journal of Environmental Impact Assessment
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• v.32 no.2
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• pp.146-156
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• 2023

Since the tourism complex development projects is promoted for areas with good natural environment and excellent landscapes, it has s significant environmental impact on the surrounding area. Therefore, this study investigated the current status and various environmental influences of tourist complex based on environmental impact assessment reports from 2012 to 2021. Based on the results of the current status analysis of the development projects, EA-INDEX for the tourism complex development projects was developed and applied to comprehensively and quantitatively analyze various environmental impacts. Through this, we investigated eco-friendliness of the development projects by year in the natural environment conservation sector, resource conservation sector, and living environment protection sector. As a result we found that the tourism complex development projects were carried out in a way that increases eco-friendliness over the past ten years, especially in in the natural environment conservation sector. On the other hand, in the case of resource conservation, it has been confirmed that eco-friendliness is decreasing, so it is necessary to make efforts to improve it when establishing new development plans in the future. It is expected that the result of this study will be useful for identifying the development trend and environmental impact of development projects. If an analysis is made that synthesizes information such as policy events and social issues related to development projects in the future, it is also expected that a broader explanation will be possible to identify trends in development projects using EA-INDEX.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.42 no.2
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• pp.86-93
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• 2019

The population of domestic companion animals is estimated to be about 10 million now. In recent years, the domestic pet market has been launching a wide range of products and services for high quality, smart and well-being. As a result, the market size will increase from 900 billion won in 2012 to 2.3 trillion won in 2016, which has more than doubled in five years. The industry expects to reach 6 trillion won by 2020, expecting 3 trillion won this year. In particular, domestic dogs and cats market is estimated at 275.5 billion won, accounting for 19% of the domestic animal market and 1.425 billion won for the world market. However, despite the growing market for companion animals products, unfortunately the import dependence on related industrial goods is still high and the quality of service is very low. Unlike Europe and the United States, 90% of companion animals are housed in apartments, often causing problems in the health and safety of companions and companions. The purpose of this study is to develop a smart house for companion animals with environmental friendliness and AI function that can be won in competition with products of developed countries. The results of this study are expected to contribute to the creation of a new value - added base for the related industries through the strengthening of the competitiveness of the related SMEs and further the effect of employment increase and import substitution.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2000.11a
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• pp.162-167
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• 2000

Synthetic water-based metal-cutting fluids are increasingly popular in the metal-working industry because of its environmental friendliness. However, the fluids have the problem to be decomposed by microbes with use. Thus, it is very important to evaluate the stabilities of the fluids against microbes for the excellent fluids. The purpose of this study is to investigate the biodegradability of several lubricating agents used to improve anti-wear property of the fluids. From the study, it was found that there existed some difference on the biodegradability against microbes such as Escherichia coli and Klepsiella pneumoniae depended on the structure of the lubricating agents and pH of the fluids.

• Current Optics and Photonics
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• v.1 no.6
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• pp.613-617
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• 2017

Due to optimal advances such as chromatic performance, durability, low power consumption, high efficiency, long-lifetime, and excellent environmental friendliness, white LEDs (WLEDs) are widely used in vehicle front lighting, backlighting, decorative lighting, street lighting, and even general lighting. In this paper, the remote packaging WLEDs (RP-WLEDs) with bi-layer red-emitting $Sr_2Si_5N_8:Eu^{2+}$ and yellow-emitting YAG:Ce phosphor was proposed and investigated. The simulation results based on the MATLAB software and the commercial software Light Tools indicated that the color rendering index (CRI) of bi-layer phosphor RP-WLEDs had a significant increase. The CRI had a considerable increase from 72 to 94. In conclusion, the results showed that bi-layer red-emitting $Sr_2Si_5N_8:Eu^{2+}$ and yellow-emitting YAG:Ce phosphor could be a prospective approach for manufacturing RP-WLEDs with enhanced optical properties.

• Korean Journal of Materials Research
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• v.22 no.6
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• pp.309-315
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• 2012

Metal foam has many excellent properties, such as light weight, incombustibility, good thermal insulation, sound absorption, energy absorption, and environmental friendliness. It has two types of macrostructure, a closed-cell foam with sealed pores and an open-cell foam with open pores. The open-cell foam has a complex macrostructure consisting of an interconnected network. It can be exploited as a degradable biomaterial and a heat exchanger material. In this paper, open cell Mg alloy foams have been produced by infiltrating molten Mg alloy into porous pre-forms, where granules facilitate porous material. The granules have suitable strength and excellent thermal stability. They are also inexpensive and easily move out from open-cell foamed Mg-Al alloy materials. When the melt casting process used an inert gas, the molten magnesium igniting is resolved easily. The effects of the preheating temperature of the filler particle mould, negative pressure, and granule size on the fluidity of the open cell Mg alloy foam were investigated. With the increased infiltration pressure, preheat temperature and granule sizes during casting process, the molten AZ31 alloy was high fluidity. The optimum casting temperature, preheating temperature of the filler particle mould, and negative pressure were $750^{\circ}C$, $400-500^{\circ}C$, and 5000-6000 Pa, respectively, At these conditions the AZ31 alloy had good fluidity and castability with the longest infiltration length, fewer defects, and a uniform pore structure.

• Journal of Electrochemical Science and Technology
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• v.11 no.4
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• pp.384-391
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• 2020

Due to its characteristics of light weight, high energy density, good safety, long service life, no memory effect, and environmental friendliness, lithium-ion batteries (LIBs) are widely used in various portable electronic products. The capacity and performance of LIBs largely depend on the performance of electrode materials. Therefore, the development of better positive and negative materials is the focus of current research. The application of metal organic framework materials (MOFs) derivatives in energy storage has attracted much attention and research. Using MOFs as precursors, porous metal oxides and porous carbon materials with controllable structure can be obtained. In this paper, rod-shaped Co-MOF-74 was grown on Ni Foam (NF) by hydrothermal method, and then Co-MOF-74/NF precursor was heat-treated to obtain rodshaped Co₃O₄/NF. Ni Foam was skeleton structured, which effectively relieved. The change of internal stress changes and destroys the structural volume of the electrode material and reduces the capacity attenuation. Co₃O₄/NF composite material has a specific discharge capacity of up to 1858 mA h/g for the first time, and a reversible capacity of up to 902.4 mA h/g at a current density of 200 mA/g, and has excellent rate and impedance performance. The synthesis strategy reported in this article opens the way to design high-performance electrodes for energy storage and electrochemical catalysis.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.5
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• pp.298-302
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• 2016

In this work, $LiMn_2O_4$ and $LiNi_{1/3}Mn_{1/3}Co_{1/3}O_2$ cathode materials are mixed by some specific ratios to enhance the practical capacity, energy density and cycle performance of battery. At present, the most used cathode material in lithium ion batteries for EVs is spinel structure-type $LiMn_2O_4$. $LiMn_2O_4$ has advantages of high average voltage, excellent safety, environmental friendliness, and low cost. However, due to the low rechargeable capacity (120 mAh/g), it can not meet the requirement of high energy density for the EVs, resulting in limiting its development. The battery of $LiMn_2O_4-LiNi_{1/3}Mn_{1/3}Co_{1/3}O_2$ (50:50 wt%) mixed cathode delivers a energy density of 483.5 mWh/g at a current rate of 1.0 C. The accumulated capacity from $1^{st}$ to 150th cycles was 18.1 Ah/g when the battery is cycled at a current rate of 1.0 C in voltage range of 3.2~4.3 V.

• Design & Manufacturing
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• v.15 no.1
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• pp.57-65
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• 2021

Pump cap is a product that is widely used due to its ease of use and simple operation. These pump caps are applied to heterogeneous functional cosmetics and are being developed as dual pump caps. However, the conventional dual pump cap has a problem in that it is inconvenient to use and leakage occurs. In addition, it is formed of a plurality of materials, and there is a problem that is difficult to recycle. Lately, since the problem of environmental pollution is getting serious, the dual pump cap, which is difficult to recycle, cannot be used. Currently, eco-friendliness has been considered in Korea, and there are no dual pump cap containers with excellent sealing performance. Therefore, in this study, a dual pump cap container made of eco-friendly material was designed. In addition, finite element analysis was performed to verify the design feasibility of the product.

• Journal of Korean Tunnelling and Underground Space Association
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• v.22 no.5
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• pp.485-500
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• 2020

Due to various advantages such as small facilities, ease of construction and so on, the grouting technology which is widely used in construction field has developed remarkably compared with the past. However, the efforts to improve the homogeneity of quality, long-term durability and environmental problems have been continued. In recent years, new grouting method has been developed in order to solve problems such as low strength, durability and leaching phenomenon of liquid glass (sodium silicate) grouting material in Korea. A newly developed method integrates the injection material with the ground by the self-healing material of crystallization growth type. For this reason, it is known that improvement of the durability and water quality of the ground, prevention of leaching, and environment friendliness can be expected. The present study applied a newly developed method to test sites and verified its effect such as injection range, improvement effect, waterproofing performance and so on. Standard penetration test, field permeability test, borehole shear test, pressuremeter test and pH test were conducted, and the results were compared between before and after developed method application. As results of tests, the field applicability and improvement effect of developed method were proved to be excellent.