• Korean Journal of Agricultural Science
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• v.41 no.4
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• pp.361-367
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• 2014

Host plants of the Henosepilachna vigintioctomaculata are known as Solanaceae plants such as potato, tomato, eggplant and Lycium chinense. Henosepilachna vigintioctomaculata (Motschulsky) cause continuous damage from early June to mid-August in leaves of L. chinense under environmental-friendly management in Cheongyang, Chungnam. The developmental period of egg and larva of H. vigintioctomaculata were investigated. H. vigintioctomaculata were reared on L. chinense at several temperatures, for example, 15, 20, 25 and $30^{\circ}C$ in the laboratory. In addition, the control effect of 5 eco-friendly agricultural materials were examined. As results, hatching rate is the highest to 91% at $25^{\circ}C$. Egg periods were 10.8, 7.7, 5.1 and 3.7 days at each tested temperature, respectively. And the total developmental periods from egg to adult were 42.7, 26.3, 18.4 and 19.4 days at each tested temperature, respectively. Otherwise, their eclosion rates from pupa to adult were showed 58%, 77%, 85%, 65% at each tested temperature, respectively. As a result of the control effect, both adults and larvae of H. vigintioctomaculata were shown a high mortality to mixture with extract of Sophora flavescens, Chenopodium ambrosioides and Melia azedarach. Additional, larvae is shown high mortality to extract of Azadirachta indica and Cymbopogon nardus. Thus H. vigintioctomaculata might be controled by using plant extract of eco-friendly agricultural materials in due season.

• Journal of Adhesion and Interface
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• v.9 no.3
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• pp.34-42
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• 2008

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.18 no.3
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• pp.300-306
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• 2009

Welding technology is applicable in many kinds of fields, with the help of its advantages such as easy operational procedure and structural simplification. However, in the process of welding, hazardous materials and fumes cause huge fire broke-outs, explosions, and health-conscious problems. Also, as heavy metals in fumes have a harmful effect on the environment, recently, this has emerged as a urgent social issue. This study has been aimed at the recommendation of the most environment-friendly, among materials currently used in plumbing welding, and it has been done at the result of the analysis of amount, ingredient, and size in collected fumes created in the experiment of welding five rods to galvanized steel pipes and steel pipe ones. At the test result, due to the effect of Zn-coating, galvanized steel pipes, when welded to rods, created more fumes than steel pipe ones. In the mean time, when it comes to welding rods, among five, WR-03 produced fumes the least. Therefore, a combination of the test results clearly indicates that the case of welding WR-03 to cast-iron pipes turned out to be the most environment-friendly.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.48 no.3
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• pp.66-72
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• 2016

The applicability of rice husk fiber as a raw material for eco-friendly pulp mold was evaluated in this study. The higher demand of environmental friendly packaging material resulted in the more interest for the natural fiber based pulp mold. The rice husk which is an abundant agricultural byproduct in Asia could be defiberized by an alkaline digestion process. The changes in the pulp mold making process and the properties of pulp mold by the addition of the rice husk were investigated. The addition of rice husk fiber to the pulp mold made with OCC or UBKP resulted in the increase in drainage at the pulp mold forming process. In case of UBKP pulp mold, the addition of rice husk fiber increased the drying efficiency after pulp mold forming since the structure of pulp mold became more bulkier by the addition of the rice husk fiber. Those results showed the rice husk fiber could be applied to the pulp mold manufacturing as one of the eco-friendly natural fiber resources.

• International Journal of Highway Engineering
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• v.14 no.4
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• pp.37-49
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• 2012

PURPOSES : This study is to investigate the fundamental properties of limestone added cement concrete for application of pavement. METHODS : As the production of Portland cement causes environmental problems, engineers have sought more environment-friendly concrete construction materials. Limestone powder can be used for concrete as a partial replacement of Portland cement. One of the great applications of limestone powder added cement concrete might be a cement concrete pavement since the concrete pavement consumes massive quantity of Portland cement. Experimental variables were different replacement level of limestone powder by 0% to 25% with 5% increment. Before hardening of fresh concrete, setting time and plastic shrinkage characteristics were investigated in addition to other basic properties. Properties of hardened concrete included compressive, tensile and flexural strength as well as drying shrinkage. RESULTS : The addition of limestone powder did not significantly affect the properties of fresh concrete. Strength deceased as the replacement ratio increased and when the replacement ratio was greater than 10% decrease rate increased. CONCLUSIONS : It was found that the partial replacement of the limestone powder to cement in pavement materials can be positively considered as its mechanical properties show comparable performance to those normal concrete.

• Journal of the Korea Furniture Society
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• v.20 no.3
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• pp.205-212
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• 2009

Through this study, I explored a creation of the postmodern furniture aesthetics through the transformation by student's interpretation in experiencing the art/craft/handmade/studio furniture aesthetics in postmodernism theoretically for 'wood culture experience class' or 'wood love experience class' by the Korea Forest Service because the class tends to focus on making simple wood works involved just in the practical part. Qualitative conceptual analysis as the principal methodology was used to achieve the theoretical context in the experience programs. Following the lesson one on defining the postmodern aesthetics in New Design furniture as metaphor and the lesson two on interpreting an aesthetics of art and everyday life with the wood furniture which expresses the metaphorical and symbolical aesthetics appeared as New Design furniture in postmodernism in the previous papers, I developed lesson three on creating an object using eco-friendly materials like wood in transforming an aesthetics of postmodern furniture as the final stage of the study. Therefore, the students will be able to create a piece of eco-friendly wood furniture for our environment as metaphor transformed by his/her perspective regarding a piece of selected New Design furniture.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.424-433
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• 2006

This paper studies the field applicability of the Special Chemical grouting Method(SCM) in reinforcing and reducing permeability of the back of an existing continuous wall. SCM uses double rod which imposes intermediate pressure$(981\sim9,810kPa)$ to disturb, cut, discharge, and mix the ground. It is observed that a bulb is formed by using cement paste and environmentally friendly injection materials with minimal alkali leaching. Uniaxial compression tests, test for chemical properties and fish poison test are performed. Test results indicate that the method results in higher durability, less leaching through use of the environmentally friendly injection material, and faster mobilization of the strength. In addition, field tests confirm the formation of the bulb and the seepage cutoff wall.

• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.2
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• pp.264-270
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• 2011

This paper focuses on possibility to design and fabrication new combination of bullet core to substitute current toxic material of heavy metal such as lead by environment-friendly ones. The core is designed as dual structure to manipulate the core center of gravity easily by combining materials, which of basis is tungsten of low cost and easily acquired. Those combinations are W-M series such as W-Cu, W-Sn, W-Cu-Sn, and W-Cu-Ni to target the density of lead, $11.34g/cm^3$ through powder-metallurgy. Out of four, combination of W-Cu-Ni shows the highest compression density of 96% and is confirmed as the most suitable substitution for lead due to the excellent property of matter and sintering. All combination samples is simulated on the PRODAS software for designing and structure analysis by adjusting the center of gravity of dual core samples forward and backward. The simulations confirm the similarity of current bullet core with respect to properties of mass, aero dynamics, and flying stability.

• Journal of the Korean Geotechnical Society
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• v.22 no.12
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• pp.25-31
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• 2006

This paper studies the field applicability of the Special Chemical grouting Method (SCM) in reinforcing and reducing permeability of the back of an existing continuous wall. SCM uses double rod which imposes intermediate pressure ($981{\sim}9,810kPa$) to disturb, cut, discharge, and mix the ground. It is observed that a bulb is formed by using cement paste and environmentally friendly injection materials with minimal alkali leaching. Uniaxial compression tests, test for chemical properties and fish poison test are performed. Test results indicate that the method results in higher durability, less leaching through the use of the environmentally friendly injection material and faster mobilization of the strength. In addition, field tests confirm the formation of the bulb and the seepage cutoff wall.

• Composites Research
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• v.36 no.6
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• pp.448-453
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• 2023

This paper explores developing sustainable 3D printing filaments using organic soybean hulls mixed with polylactic acid (PLA). The study experiments with various particle sizes and mixing ratios, examining the physical and mechanical properties of the resulting filaments. Results show that smaller soybean hull particles and specific mixing ratios enhance the filament's quality while maintaining PLA's characteristics. This research signifies a step towards environmentally friendly 3D printing materials, offering a viable alternative to conventional filaments and addressing ecological concerns in the industry.