• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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• pp.265-266
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• 2006

It was well known that thermopile was quiet a competent sensor using to probe the temperature of "hot point" where the temperature can be off the temperature-limitation for normal operation of the main electrical power equipment. In the present work, we aimed for developing new Ge-thermopile materials which can be using a non-contact temperature sensors at various hot-point of the power equipment and evaluation of its output property. As a results of the present works, a new thermopile which were composed Ga-poded p-type and Sb-doped n-type in Ge-semiconductor were designed and manufactured by MBE(Molecular Beam Epitaxy) process and showed superior sensitivity at room temperature.

• 대한기계학회논문집A
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• 제39권9호
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• pp.871-877
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• 2015

다양한 기계부품과 센서류가 포함된 수중로봇, 무인 잠수정 등과 같은 심해장비 시스템은 수심에 따른 높은 수압과 온도, 조류 등 심해의 복합적인 극한 환경조건의 영향을 받기 때문에 실제 현장에서 사용되기 전에 제품의 신뢰성을 검증하는 것이 매우 중요하다. 이러한 복합적인 해양환경을 재현하여 제품에 대한 실증적인 시험을 할 수 있는 시험장비의 구축이 요구되는 실정이다. 본 연구를 통하여 최대수압 2.0MPa, 수온 $5{\sim}60^{\circ}C$, 최대유속 2 m/s의 복합 환경조건의 구현이 가능한 워크인 타입의 수중복합 환경시험장비를 구성하는 주요 구성품의 개발 요구사양 및 설계방안을 제시하고 이를 통해 심해장비 시스템 및 모듈 부품에 대한 제품 신뢰도를 검증할 수 있는 시험장비의 개발 내용을 제시하고자 한다.

• Advances in nano research
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• 제14권3호
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• pp.235-246
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• 2023

Nanotechnology, like any other revolutionary innovation in materials science, has significantly influenced the level of competition in sports. Nanotechnology provides various benefits and enormous potential to enhance athletic equipment, making players safer, more comfortable, and more agile. Various sporting equipment is being infused with nanomaterials, including carbon nanotubes (CNTs), silica nanoparticles (SNPs), nanoclays fullerenes, etc., to enhance athlete and equipment performance. Each of these nanomaterials gives athletic equipment an extra benefit like high strength and stiffness, longevity, decreased weight, abrasion resistance, etc. This paper mechanically analysis the structural strength of tennis equipment to avoid injury. As a result, the bending forces are applied to the reinforced structures to investigate their durability.

• Advances in environmental research
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• 제6권1호
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• pp.15-23
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• 2017

Powdered marble wastes (PMW) generated by Utique marble cutting industries (North of Tunisia) with abundant amounts were used in this study as low-cost materials to investigate the stabilization of heavy metals (Pb, Zn, Fe) in sludge generated from a local Zn-Electroplating factory. Powdered marble wastes were evaluated by means of chemical fractions of heavy metals in sludge and concentrations of heavy metals in leachate from columns to determine their ability to stabilize heavy metals in contaminated sludge. Results indicated that chemical fractions of heavy metals in sludge were affected by application of the PMW mineral materials and pH, however, the effects varied with heavy metals. Application of the powdered marble wastes mineral materials reduced exchangeable metals in the sequence of Pb (60.5%)>Fe (40.5%)>Zn (30.1%). X-ray diffraction and hydro-geochemical transport code PHREEQC analysis were successfully carried out to get a better understanding of the mechanisms of reactive mineral phases involved in reduced exchangeable heavy metals in sludge after PMW material amendments. Therefore, metal immobilization using powdered marble wastes materials is an effective stabilization technique for industrial metallic hydroxide sludge.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 E
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• pp.1663-1665
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• 1998

The power distribution system is 22.9 kV-y neutral point multi-ground one in our country. So, if conducting materials contacted, to the power line electrical equipment faults or stoppage of electrical power supply happened in the line. contacts are caused by magpie or its nest materials, especially, electrical power incidents by magpie from February to May, season layed egg, is high as 30% as. It is important to electrical power supplier to protect electrical power equipment caused by magpie. From now, KEPCO have tried to protect electrical power equipment faults caused by magpie using several methods, but have not acquired good results and continued to withdraw the nest. Recently, nature environment protection expand to around country and KEPCO also changed the nest withdrawal method to new pre-protection method coexisted with magpie, "Environmental Affinitive Pre-protection Counterplan". Therefore, we planned environmental affinitive pre-protection equipment, set test line. Also, after analyzed its effects during 1 year, we satisfied with results, and then expanded to other test lines and regions.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2007년도 춘계학술대회 논문집
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• pp.397-400
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• 2007

Recently, rheology forming technology has been interested in industrial and academic for light weight materials and to solve environmental issues. In this study, the rheology material production equipments were used to be made spiral shape by special design. And the experiment variables established stirring time 0 $\sim$ 1200 sec, stirring velocity 0 $\sim$ 100 rpm and several material temperature of semi - solid states. The rheology materials were made for established experiment conditions then measured mechanical properties. Sequence-production equipments were appended to fabrication system of rheology material for make rheology materials continually. Therefore, the development of sequence-production equipments were demanded for fine grains and for uniform globule shape rheology materials by a specially designed spiral stirrer machine.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2008년도 추계학술발표대회 및 제15회 신소재 심포지엄
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• pp.4.1-4.1
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• 2008

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2004년도 제5회 정기학술발표대회 논문집
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• pp.539-542
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• 2004

최근 건축물의 대형화, 고층화 경향에 따라, 현장에서 취급되는 자재의 종류는 갈수록 다양해지며, 자재의 양도 방대해 지고 있다. 세분화된 공정으로 인해 서로 다른 공정이 동시 다발적으로 진행되기 때문에 현장에서 작업동선 및 물류의 이동이 매우 복잡해진다. 이에 따라, 효율적인 자재 반입 및 양중이 필요하다. 특히 마감 공사 시에 마감자재와 설비자재와의 반입 충돌과 공정상의 불일치로 인해 건물에 양중 문제가 발생하고 있다. 본 논문은 이를 분석하고 문제점에 영향을 미치는 요소들을 파악하여 효과적인 자재 양중방향을 제시한다.

• Journal of Radiation Protection and Research
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• 제48권4호
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• pp.167-174
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• 2023

Background: A nondestructive test is commonly used to inspect the surface defects and internal structure of an object without any physical damage. X-rays generated from an electron accelerator or a tube are one of the methods used for nondestructive testing. The high penetration of X-rays through materials with low atomic numbers makes it difficult to discriminate between these materials using X-ray imaging. The interaction characteristics of neutrons with materials can supplement the limitations of X-ray imaging in material discrimination. Materials and Methods: The radiation image acquisition process for air-cargo security inspection equipment using X-rays and neutrons was simulated using a GEometry ANd Tracking (Geant4) simulation toolkit. Radiation images of phantoms composed of 13 materials were obtained, and the R-value, representing the attenuation ratio of neutrons and gamma rays in a material, was calculated from these images. Results and Discussion: The R-values were calculated from the simulated X-ray and neutron images for each phantom and compared with those obtained in the experiments. The R-values obtained from the experiments were higher than those obtained from the simulations. The difference can be due to the following two causes. The first reason is that there are various facilities or equipment in the experimental environment that scatter neutrons, unlike the simulation. The other is the difference in the neutron signal processing. In the simulation, the neutron signal is the sum of the number of neutrons entering the detector. However, in the experiment, the neutron signal was obtained by superimposing the intensities of the neutron signals. Neutron detectors also detect gamma rays, and the neutron signal cannot be clearly distinguished in the process of separating the two types of radiation. Despite these differences, the two results showed similar trends and the viability of using simulation-based radiation images, particularly in the field of security screening. With further research, the simulation-based radiation images can replace ones from experiments and be used in the related fields. Conclusion: The Korea Atomic Energy Research Institute has developed air-cargo security inspection equipment using neutrons and X-rays. Using this equipment, radiation images and R-values for various materials were obtained. The equipment was reconstructed, and the R-values were obtained for 13 materials using the Geant4 simulation toolkit. The R-values calculated by experiment and simulation show similar trends. Therefore, we confirmed the feasibility of using the simulation-based radiation image.

• 한국주거학회논문집
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• 제14권4호
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• pp.11-19
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• 2003

This study intends to predict prospective defects and establish the plan of Preventive Maintenance through research and analysis of defect occurrences and their repair costs in the public equipment of ‘H’ apartment house from 1998 to 2001. According to results of the analysis, more than 90% of defects and their repair costs for 4 years of the building have occurred in heating, hot water and water supply equipments. In case of specific classification in each equipment, more than 60% of defects were found at hot water pipes and heating pipes, and their repair costs covered more than 60% of the total defect costs. After two repairs by ‘Preventive Maintenance’ had been performed in the year 1998, total defects and defects of each equipment each yew have increased in number from 1999 to 2001. But total repair costs and repair costs of each equipment have not increased as time has gone by, because repair costs have relationship with the price of materials and labor, the part of defect and the scale of repair.