• Title, Summary, Keyword: SEM

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Skin Improvement Effect of Mask Pack with Snail Fermented Extract (달팽이 발효 추출물을 이용한 마스크 팩의 피부개선효과)

  • Zhoh, Choon-Koo;Lee, Min-Hee;Kim, In-Young;Shin, Ji-Young
    • Journal of the Korean Applied Science and Technology
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    • v.33 no.1
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    • pp.30-40
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    • 2016
  • This study related to get skin improvement effect of sheet mask pack using 5% of $2^{nd}$ fermented snail extract. To the scientific study of the skin, it was used for this sheet mask of 100% cotton as cutting face shape. We reported the results of measurement of skin improvement effect with the placebo and Gene-SEM (general snail extract mask). First; moisturizing effect of 2F-SEM ($2^{nd}$ fermented snail extract mask) has been increased about 11% than the PM and Gene-SEM was improved about 4.7% more than the PM (placebo mask). Second; elasticity of the mask pack containing $2^{nd}$ fermented snail extract was 13.8% better than PM and Gene-SEM was improved about 6.7 % more than PM. Third; Skin roughness of 2F-SEM has improved 6.80% than PM and Gene-SEM was improved about 2.3% more than PM. Fourth; melanin reductive effect of 2F-SEM was improved about15.0% more than PM and Gene-SEM was improved about 8.7% more than PM. Fifth; fine wrinkle decline effect of 2F-SEM was about 8.0% better than PM and Gene-SEM was improved with 5.1% more than PM. Sixth; sensorial evaluation of 2F-SEM using $2^{nd}$ fermented snail extract was significantly showed difference merits regarding softness, moisture, fine-wrinkle improvement.

하이브리드 SEM 시스템

  • Kim, Yong-Ju
    • Proceedings of the Korean Vacuum Society Conference
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    • pp.109-110
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    • 2014
  • 주사전자현미경(Scanning Electron Microscopy: SEM)은 고체상태에서 미세조직과 형상을 관찰하는 데에 가장 다양하게 쓰이는 분석기기로서 최근에 판매되고 있는 고분해능 SEM은 수 나노미터의 분해능을 가지고 있다. 그리고 SEM의 초점심도가 크기 때문에 3차원적인 영상의 관찰이 용이해서 곡면 혹은 울퉁불퉁한 표면의 영상을 육안으로 관찰하는 것처럼 보여준다. 활용도도 매우 다양해서 금속파면, 광물과 화석, 반도체 소자와 회로망의 품질검사, 고분자 및 유기물, 생체시료 nnnnnnnnn와 유가공 제품 등 모든 산업영역에 걸쳐 있다(Fig. 1). 입사된 전자빔이 시료의 원자와 탄성, 비탄성 충돌을 할 때 2차 전자(secondary electron)외에 후방산란전자(back scattered electron), X선, 음극형광 등이 발생하게 되는 이것을 통하여 topography (시료의 표면 형상), morphology(시료의 구성입자의 형상), composition(시료의 구성원소), crystallography (시료의 원자배열상태)등의 정보를 얻을 수 있다. SEM은 2차 전자를 이용하여 시료의 표면형상을 측정하고 그 외에는 SEM을 플랫폼으로 하여 EDS (Energy Dispersive X-ray Spectroscopy), WDS (Wave Dispersive X-ray Spectroscope), EPMA (Electron Probe X-ray Micro Analyzer), FIB (Focus Ion Beam), EBIC (Electron Beam Induced Current), EBSD (Electron Backscatter Diffraction), PBMS (Particle Beam Mass Spectrometer) 등의 많은 분석장치들이 SEM에 부가적으로 장착되어 다양한 시료의 측정이 이루어진다. 이 중 결정구조, 조성분석을 쉽고 효과적으로 할 수 있게 하는 X선 분석장치인 EDS를 SEM에 일체화시킨 장비와 EDS 및 PBMS를 SEM에 장착하여 반도체 공정 중 발생하는 나노입자의 형상, 성분, 크기분포를 측정하는 PCDS(Particle Characteristic Diagnosis System)에 대해 소개하고자 한다. - EDS와 통합된 SEM 시스템 기본적으로 SEM과 EDS는 상호보완적인 기능을 통하여 매우 밀접하게 사용되고 있으나 제조사와 기술적 근간의 차이로 인해 전혀 다른 방식으로 운영되고 있다. 일반적으로 SEM과 EDS는 별개의 시스템으로 스캔회로와 이미지 프로세싱 회로가 개별적으로 구현되어 있지만 로렌츠힘에 의해 발생하는 전자빔의 왜곡을 보정을 위해 EDS 시스템은 SEM 시스템과 연동되어 운영될 수 밖에 없다. 따라서, 각각의 시스템에서는 필요하지만 전체 시스템에서 보면 중복된 기능을 가지는 전자회로들이 존재하게 되고 이로 인해 SEM과 EDS에서 보는 시료의 이미지의 차이로 인한 측정오차가 발생한다(Fig. 2). EDS와 통합된 SEM 시스템은 중복된 기능인 스캔을 담당하는 scanning generation circuit과 이미지 프로세싱을 담당하는 FPGA circuit 및 응용프로그램을 SEM의 회로와 프로그램을 사용하게 함으로 SEM과 EDS가 보는 시료의 이미지가 정확히 일치함으로 이미지 캘리브레이션이 필요없고 측정오차가 제거된 EDS 측정이 가능하다. - PCDS 공정 중 발생하는 입자는 반도체 생산 수율에 가장 큰 영향을 끼치는 원인으로 파악되고 있으며, 생산수율을 저하시키는 원인 중 70% 가량이 이와 관련된 것으로 알려져 있다. 현재 반도체 공정 중이나 반도체 공정 장비에서 발생하는 입자는 제어가 되고 있지 않은 실정이며 대부분의 반도체 공정은 저압환경에서 이루어지기에 이 때 발생하는 입자를 제어하기 위해서는 저압환경에서 측정할 수 있는 측정시스템이 필요하다. 최근 국내에서는 CVD (Chemical Vapor Deposition) 시스템 내 파이프내벽에서의 오염입자 침착은 심각한 문제점으로 인식되고 있다(Fig. 3). PCDS (Particle Characteristic Diagnosis System)는 오염입자의 형상을 측정할 수 있는 SEM, 오염입자의 성분을 측정할 수 있는 EDS, 저압환경에서 기체에 포함된 입자를 빔 형태로 집속, 가속, 포화상태에 이르게 대전시켜 오염입자의 크기분포를 측정할 수 있는 PBMS가 일체화 되어 반도체 공정 중 발생하는 나노입자 대해 실시간으로 대처와 조치가 가능하게 한다.

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Optimum Design Section of Non-open Cut Underpass Construction Method, Super Equilibrium Method(SEM) by Numerical Analysis (수치해석에 의한 비개착 공법(SEM)의 최적 설계단면 결정)

  • Kim, Hyun Ki;Choi, Chan Yong;Kim, IL Byung
    • Journal of The Korean Society For Urban Railway
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    • v.6 no.3
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    • pp.139-149
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    • 2018
  • Due to the improvement of the performance of the traffic facilities and the construction of the new facilities, traffic facilities in the ground and underground are frequently accompanied and crossed. In particular, horizontal drilling works will be carried out for the construction of roads, subways, railways, etc. in the urban areas. Such excavation works will cause settlement and deformation in the upper ground or facilities and it is necessary to minimize the damage. In this study, we developed a super equilibrium method (SEM) that can effectively suppress the settlement and the initial settlement of the excavation upper ground during low - to - highway excavation. This method uses small diameter steel tubes or steel plates. The performance of each component required by this method was studied through numerical analysis. For this purpose, the characteristics of the SEM method in the untreated state were evaluated and the change of the pure ground stress was confirmed. And we defined requirements for each component(SEM file, SEM plate). The performance of the SEM method was evaluated by changing the material, stiffness, length, and installation angle. Finally, optimal design section for SEM method could be suggested.

A Development of SEM Applied Microjoining System (SEM을 이용한 미세 접합 시스템 개발)

  • 황일한;나석주
    • Journal of Welding and Joining
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    • v.21 no.4
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    • pp.63-68
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    • 2003
  • Scanning electron microscopy (SEM) has been used as a surface measurement instrument and a tool for lithography in semiconductor process due to its high density localized beam. For those purposes, however, the maximum current of SEM Is less than 100pA, which is not enough fo material processing. In this paper SEM was modified to increase the amount of current reaching a specimen from gun part where current is generated, the possibility of applying SEM to material processing, especially microjoining, was investigated. The maximum current of SEM after modifications was measured up to 10$\mu$A, which is about 10$^{5}$ times greater than before modifications. Through experiments such as eutectic solder wetting on thin 304 stainless steel foil and microjoining of 10$\mu$m thick 304 stainless steel, the intensity of electron beam of SEM proved to be great enough fur material processing as heat source. And a tight jig system was found necessary to hold materials close enough fur successful microloining.

SEM-CT: Comparison of Problem Solving Processes in Science(S), Engineering(E), Mathematic(M), and Computational Thinking(CT) (SEM-CT: 과학(S), 공학(E), 수학(M)적 문제해결과정과 컴퓨팅 사고(CT))

  • Nam, Younkyeong;Yoon, JinA;Han, KeumJoo;Jeong, JuHun
    • The Journal of Korean Association of Computer Education
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    • v.22 no.3
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    • pp.37-54
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    • 2019
  • The main purpose of STEM education is to understand methods of inquiry in each discipline to develop convergent problem solving skills. To do this, we must first understand the problem-solving process that is regarded as an essential component of each discipline. The purposes of this study is to understand the relationship between the problem solving in science (S), engineering (E), mathematics (M), and computational thinking (CT) based on the comparative analysis of problem solving processes in each SEM discipline. To do so, first, the problem solving process of each SEM and CT discipline is compared and analyzed, and their commonalities and differences are described. Next, we divided the CT into the instrumental and thinking skill aspects and describe how CT's problem solving process differs from SEM's. Finally we suggest a model to explain the relationship between SEM and CT problem solving process. This study shows how SEM and CT can be converged as a problem solving process.

Determination of Semicarbazide in PVC Gaskets of Food Bottle Cap and Foods (식품병마개 PVC gasket과 식품에 함유된 semicarbazide의 분석)

  • Park, Sang-Wook;Lee, Kwang-Ho;Kwak, In-Shin;Jeon, Dae-Hoon;Lee, Si-Kyung
    • Korean Journal of Food Science and Technology
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    • v.37 no.3
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    • pp.334-338
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    • 2005
  • Method was developed to efficiently analyze semicarbazide (SEM) in foods. Although SEM is produced by thermal decomposition of blowing agent azodicarbonamide, it is too small to be activated by ultraviolet light or fluorescence. When 2-nitrobenzaldehyde semicarbazone, derivatization of SEM, was analyzed by HPLC with triple column system, coefficient correlation over 0.9997 and detection limit of 0.48 ng/g were observed. SEM level in commercial bottle cap gasket was 812.20-5771.30ng/g. Recoveries for SEM in food and PVC gasket were 83.45-97.33% and 92.12-98.71%, respectively. SEM level in plastic seals of press twist-off metal lids was ND-5771.330ng/g.

Observations of the Cyanobacteria Synechocystis sp. PCC 6803 using Cryo-Methods and Cryo-SEM (Cryo-Methods와 Cryo-SEM을 이용한 Cyanobacteria, Synechocystis sp. PCC 6803 미세구조 관찰)

  • Lee, Eun-Ju;Moon, Yoon-Jung;Oh, Hyun-Woo;Kim, Su-Jin;Chung, Young-Ho;Kweon, Hee-Seok;Kim, Youn-Joong
    • Applied Microscopy
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    • v.39 no.1
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    • pp.65-72
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    • 2009
  • Cryo-SEM which enables specimens to be observed in frozen form has been used to study liquid specimens in their native states. Cryo-methods, sample preparation for cryo-SEM, are quite complex and involve several discrete but vitally interconnected steps which are rapid cooling, fracturing, sectioning, etching and coating. It is important to select practical techniques and to optimize conditions of each steps considering analytic purpose and specimen characters, viz., sample dimension, water contents. In this study, etching methods and sample preparation before freezing had been studied for observation of cyanobacteria, Synechocystis sp. PCC 6803 using cryo-SEM and their cryo-SEM images were compared to Conventional SEM (CSEM) images treated by chemical fixation. We could observe the improved morphological images of the pili of the surface and membranes of Synechocystis sp. PCC 6803 and the three-dimensional architectures of their biofilm, which were difficult to observe using chemical fixation and CSEM. These results suggest that cryo-methods/cryo-SEM are useful techniques for morphological study of biological specimen.

Observation of Dynamic Domain Patterns using Lorentz SEM (로렌츠 SEM을 이용한 동적자구 모양의 관찰)

  • ;K. I. Arai
    • Journal of the Korean Magnetics Society
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    • v.5 no.5
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    • pp.885-891
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    • 1995
  • This paper discussed on the observation of dynamic domain patterns using Lorentz SEM in the frequency region of 50 Hz-10 kHz. The observed dynamic domain patterns were compared with the simulated ones. The observation rrethod is characterized by using the slight difference between the exciting frequency and the multiples of the scannning frequency of SEM.

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Thermoelectric Properties of Fe-doped $CoSb_3$ Prepared by Encapsulated Induction Melting and Hot Pressing

  • Park, Kwan-Ho;Kim, Mi-Jung;Jung, Jae-Yong;You, Sin-Wook;Lee, Jung-Il;Ur, Soon-Chul;Kim, Il-Ho
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • pp.686-687
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    • 2006
  • The encapsulated induction melting and hot pressing were employed to prepare Fe-doped $CoSb_3$ skutterudites and their thermoelectric properties were investigated. Single phase $\delta-CoSb_3$ was successfully obtained by the subsequent heat treatment at 773K for 24 hours. Iron atoms acted as electron acceptors by substituting cobalt atoms. Thermoelectric properties were remarkably improved by the appropriate doping. $Co_{0.7}Fe_{0.3}Sb_3$ was found as an optimum composition for best thermoelectric properties in this work.

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Thermoelectric Properties of Ni-doped $CoSb_3$ Prepared by Encapsulated Induction Melting and Hot Pressing

  • Kim, Mi-Jung;Park, Kwan-Ho;Jung, Jae-Yong;You, Sin-Wook;Lee, Jung-Il;Ur, Soon-Chul;Kim, Il-Ho
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • pp.688-689
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    • 2006
  • Ni-doped $CoSb_3$ was prepared by the encapsulated induction melting and hot pressing, and its doping effects on the thermoelectric properties were investigated. Single phase $\delta-CoSb_3$ was successfully obtained by the subsequent heat treatment at 773K for 24 hours. Nickel atoms acted as electron donors by substituting cobalt atoms. Thermoelectric properties were remarkably improved by the appropriate doping.

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