• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2008.10a
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• pp.53-54
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• 2008

섬유 제조에서부터 제품의 소비에 걸친 각 공정에 이르기까지 환경 부하 절감 대책과 섬유 제조 기술에 따른 문제 해결을 위하여 환경 친화적 섬유인 대나무 섬유, 콩 섬유, 재생 섬유, 생분해 되는 섬유 등 다양한 환경 친화적 신소재에 대한 특성을 고찰하고자한다. 환경 친화적 신소재와 섬유 폐기 공정에서의 환경친화적 신소재인 생분해 플라스틱 및 생분해 섬유의 개념을 정의하였다. 환경친화 제품 개발이 여러 가지 면에서 생산자의 부담요인으로 작용할 수 도 있으나, 중장기적으로 볼 때 환경 개선에 기여할 뿐만 아니라 기술 확보 및 시장 개척에 용이할 것이며 소비자들은 환경적, 건강적 이유로 환경친화적 제품에 많은 관심을 가지고 있다. 따라서 제품의 제품개발자들은 공정단계에서 폐기단계에 이르기까지 비용을 감수하더라도 환경 친화적 제품개발에 노력해야 할 것이다.

• Electronics and Telecommunications Trends
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• v.16 no.4 s.70
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• pp.23-40
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• 2001

광 MEMS(Optical MEMS)는 미세 기계, 전자 및 광학기술이 조합하여 이루어지는 종합적인 기술분야로서 정보통신 핵심부품의 정밀화, 고성능화, 경량화 추세에 의해 그 중요성을 더해가고 있다. 본 논문은 정보통신 기술분야에 적용되고 있는 광 MEMS 기술에 대하여 살펴본 것으로, MEMS 시스템을 구성하고 있는 광학적 구성요소의 기술개발 현황, 신소재 및 새롭게 도출된 아이디어 등에 대하여 최신 연구동향을 중심으로 조사.분석하였다. 정보통신 기술의 발전에 따라 응용분야도 다양해지며 신소재의 출현에 따른 새로운 연구분야가 확대되는 등 광 MEMS 기술의 전반적인 기술추세에 대해 전망하였다.

• Journal of the Korean Society for Advanced Composite Structures
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• v.6 no.1
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• pp.38-44
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• 2015

In this paper, a finite element dynamic simulation study was performed to gain an insight about the blast wall test details for the offshore structures. The simulation was verified using qualitative and quantitative comparisons for different materials. Based on in-depth examination of blast simulation recordings, dynamic behaviors occurred in the blast wall against the explosion are determined. Subsequent simulation results present that the blast wall made of high energy absorbing high manganese steel performs much better in the shock absorption. In this paper, the existing finite element shock analysis using the LS-DYNA program is further extended to study the blast wave response of the corrugated blast wall made of the high manganese steel considering strain rate effects. The numerical results for various parameters are verified by comparing different material models with dynamic effects occurred in the blast wall from the explosive simulation.

• Journal of the Korean Society for Advanced Composite Structures
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• v.1 no.1
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• pp.34-45
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• 2010

This paper describes the design, manufacturing process, testing, application, and assessment of capacity-ratings of the first all advanced composites bridge on a public highway system. In order to verify the bridge design prior to the field application, a sub-scale bridge superstructure was built and tested in the laboratory. The field load test results were compared with those of the finite element analysis for the verification of validity. To investigate its in-service performance, field load testing and visual inspections were conducted under an actual service environment. The paper includes the presentation and discussion for advanced composites bridge capacity rating based on the stress modification coefficients obtained from the test results. The test result indicates that the advanced composites bridge has no structural problems and is structurally performing well in-service as expected. Since these composite materials are new to bridge applications, reliable data is not available for their in-service performance. The results may provide a baseline data for future field advanced composites bridge capacity rating assessments and also serve as part of a long-term performance of advanced composites bridge.

• Journal of the Korean Geosynthetics Society
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• v.8 no.1
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• pp.61-66
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• 2009

This paper presented that the causes on failure of reinforced slope are analyzed which based on the analyzed result. It had been applied that a method of lowering the groundwater using deepwell for sump. For the stability analysis on applied method, a series of numerical analysis were carried out. Therefore, it could be confirmed that slope stability was affected the dewatering ability of groundwater by the rainfall and this method which was confirmed very reasonable and suitable methods for slope stability, during heavy rainfall, in field.

• Journal of the Korean Geosynthetics Society
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• v.17 no.4
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• pp.239-249
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• 2018

Typically, soft clay improvement is carried out using installation of PVD and surcharge method. According to circumstances, installed PVD has left for a long time due to the change in construction schedule. Therefore, for simulation of this kind of condition, discharge capacity tests were carried out under a series of temperature condition (30, 35, $40^{\circ}C$). The results indicated that under water confinement, the discharge capacities significantly reduced with elapsed time. And, the empirical equation by Miura and Chai (2000) was used for estimating the long-term in-clay discharge capacity. Based on the test results, it is recommended that in term of long-term discharge capacity, Miura and Chai's equation and reliability evaluation using discharge capacity tests under a series of temperature condition may be used.

• Journal of the Korean Geosynthetics Society
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• v.16 no.4
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• pp.103-111
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• 2017

Saudi Arabia coastal area is highly valuable construction as a flat area covered by sabkha deposit. However, sabkha deposit has some geotechnical problems because of high groundwater level, high salt contents in groundwater, loose density, and possibility of collapsible settlement due to presence of crystals vulnerable to moisture, and ground improvement is needed to improve the bearing capacity. In this study, the characteristics of the sabkha soils in the coastal area of Saudi Arabia were analyzed and the applicability of dynamic compaction method was evaluated. Parametric study was conducted to analyze the behavior of sabkha deposit during dynamic compaction. The appropriateness of the proposed analytical solutions to estimate the depth of improvement was evaluated, and the troubles and notes in applying dynamic compaction in sabkha deposit were discussed.

• Journal of the Korean Geosynthetics Society
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• v.5 no.4
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• pp.1-10
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• 2006

In This paper, the settlements of soft ground and the undrained shear strength were compared for verify the improvement effect of PBD method, completed in the Busan New Port phase 1-1 site. Through the describing of design cases with the PBD method, the effects of the improvement method with CPT data were evaluated comparing with measured results. We expect that the output from this research is useful in future for design and analysis when similar soft grounds are planned to be used.

• Journal of the Korean institute of surface engineering
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• v.56 no.6
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• pp.437-442
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• 2023

This research aims to enhance the efficiency of Pt/C catalysts due to the limited availability and high cost of platinum in contemporary fuel cell catalysts. Nano-sized platinum particles were distributed onto a carbon-based support via the polyol process, utilizing the metal precursor H₂PtCl₆·6H₂O. Key parameters such as pH, temperature, and RPM were carefully regulated. The findings revealed variations in the particle size, distribution, and dispersion of nano-sized Pt particles, influenced by temperature and pH. Following sodium hydroxide treatment, heat treatment procedures were systematically executed at diverse temperatures, specifically 120, 140, and 160 ℃. Notably, the thermal treatment at 140 ℃ facilitated the production of Pt/C catalysts characterized by the smallest platinum particle size, measuring at 1.49 nm. Comparative evaluations between the commercially available Pt/C catalysts and those synthesized in this study were meticulously conducted through cyclic voltammetry, X-ray diffraction (XRD), and field-emission scanning electron microscopy-energy dispersive X-ray spectroscopy (FE-SEM EDS) methodologies. The catalyst synthesized at 160 ℃ demonstrated superior electrochemical performance; however, it is imperative to underscore the necessity for further optimization studies to refine its efficacy.

• Journal of the Korean Geosynthetics Society
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• v.7 no.2
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• pp.7-13
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• 2008

Geosynthetic damage has attracted a major attention since the introduction of geotextiles for civil construction applications. Geotextile is one of the most useful and effective polymer material in civil construction works and the main function of geotextile is separation, reinforcement, filtering and drainage. Recently, because of the shortage of natural rock, traditional forms of river and coastal structures have become very expensive to build and maintain. This study tries to suggest the method of estimating valid stitching rate and the methodology of sea dyke construction over soft soils for more reasonable application of geotextile mat by studying tensile strength, bursting strength, punching strength, tear strength that are considered when analyzing and designing geotextile mat of a field.