• Title/Summary/Keyword: SML

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Optical and Electrical Properties of InAs Sub-Monolayer Quantum Dot Solar Cell

  • Han, Im-Sik;Park, Dong-U;No, Sam-Gyu;Kim, Jong-Su;Kim, Jin-Su;Kim, Jun-O
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.08a
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    • pp.196.2-196.2
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    • 2013
  • 본 연구에서는 분자선 에피택시 (MBE)법으로 성장된 InAs submonolayer quantum dot (SML-QD)을 태양전지에 응용하여 광학 및 전기적 특성을 평가하였다. 본 연구에서 사용된 양자점 태양전지(quantum dot solar cell, QDSC)의 구조는 n+-GaAs 기판 위에 n+-GaAs buffer와 n-GaAs base layer를 차례로 성장 한 후, 활성영역에 InAs/InGaAs SML-QD와 n-GaAs spacer layer를 8주기 형성하였다. 그 위에 p+-GaAs emitter, p+-AlGaAs window layer를 성장하고 ohmic contact을 위하여 p+-GaAs 를 성장하였다. SML-QD 구조의 두께는 0.3 ML 이며, 이때 SML-QD의 적층수를 4 stacks 으로 고정하였다. SML-QD 와의 비교를 위하여 2.0 ML크기의 InAs자발 형성 양자점 태양전지(SK-QDSC)과 GaAs 단일 접합 태양전지 (reference-SC)를 동일한 성장조건에서 제작하였다. PL 측정 결과, 300 K에서 SML-QD의 발광 피크는 SK-QD 보다 고에너지에서 나타나는데(1.349 eV), 이것은 SML-QD가 SK-QD보다 작은 크기를 가지기 때문으로 사료된다. SML-QD는 single peak를 보이는 반면, SK-QD는 dual peaks (1.112 / 1.056 eV)을 확인하였다. SML-QD의 반치폭(full width at half maximum, FWHM)이 SK-QD에 비하여 작은 것으로 보아 SML-QD가 SK-QD보다 양자점 크기 분포의 균일도가 높은 것으로 해석된다. Illumination I-V 측정 결과, SML-QDSC의 개방 전압(VOC) 과 단락전류밀도(JSC)는 SK-QDSC의 값과 비교해 보면, 각각 47 mV와 0.88 mA/cm2만큼 증가하였다. 이는 SK-QD보다 상대적으로 작은 크기를 가진 SML-QD로 인해 VOC가 증가되었으며, SML-QD가 SK-QD 보다 태양광을 흡수할 수 있는 영역이 비교적 적지만, QD내에 존재하는 energy level에서 탈출 할 수 있는 확률이 더 높음으로써 JSC가 증가한 것으로 분석 된다.

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Renovation plans of operation field of Seoul Metro Line 9 (서울 도시철도 9호선의 운영분야 혁신방안)

  • Han, Woo-Jin;Park, Jeong-Soo
    • Proceedings of the KSR Conference
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    • 2008.06a
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    • pp.1441-1446
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    • 2008
  • Seoul Metro Line 9 (SML9) is the first subway line that private capital invests in Korea. SML9 will cross Seoul, linking the Gimpo Airport to the Gangnam district (25.5km) opening in the first half of 2009. SML9 has a new model in Korea constructed by metropolitan government and private company and operated by specialized public transportation service provider. SML9 is confronted with tough environment of stagnated public transportation and strong competitor, Olympic city expressway. And SML9 is under pressure for showing high efficiency as non-governmental organization from both customers and government. Consequently SML9 must lead the maximum efficiency by using its material and human resource. It is necessary that SML9 raise a competitive power and display its ability in active collaboration with relative organization and company. Hereupon, I propose renovation plans from viewpoint of operation field of SML9, (1) efficient train scheduling regime focusing on the combination of express and local train (2) close connection of other mean of transportation and (3) effective connection convention with Airport Railroad (AREX) as the line connected directly.

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A Study on Improvement of Seoul Metro Line 9 Focusing on Marketing and Operating (영업 및 운전 중심의 서울 지하철 9호선 개선 방안 연구)

  • Park, Jeong-Soo;Han, Woo-Jin
    • Journal of the Korean Society for Railway
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    • v.11 no.5
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    • pp.482-488
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    • 2008
  • Seoul Metro Line 9 (SML9) will link Gimpo Airport to the Gangnam district opening in May 2009. SML9 has a new model in Korea constructed by metropolitan government and private company and operated by specialized public transportation service provider. SML9 is confronted with tough environment of stagnated public transportation and strong competitor, Olympic city expressway. Consequently SML9 must lead the maximum efficiency by using its material and human resource. Hereupon, I propose renovation plans from 3 viewpoints of operation field of SML9: Rapid-Local combination, close connection with other transportation and direct connecting service into Incheon Air-port Railroad(AREX).

Developing the forest classification technique in Namjeju area using high resolution satellite images and SML (Spatial Modeling Language) (고해상도 위성영상과 SML을 이용한 남제주 지역의 임상분류 기법 개발)

  • Jo Myung-Hee;Jo Yun-Won;Kim Sung-Jae;Song Wan-Young;Chung Young-Kyo
    • Proceedings of the KSRS Conference
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    • 2006.03a
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    • pp.359-364
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    • 2006
  • 최근 GIS를 비롯한 공간정보기술의 눈부신 발전으로 국토전반에 대한 정보화와 과학적인 관리기법이 확산되고 있다. 이에 효율적인 산림관리를 위하여 위성영상과 지리정보시스템을 이용한 산림정보가 구축되고 있으나, 산림지역이라는 지리특성상 현장 출입이 제한적이고 위험하여 정보수집에 어려움이 있다. 본 연구에서는 효율적인 산림정보구축을 위하여 남제주군을 대상으로 고해상도 위성영상과 공간정보추출언어인 SML(Spatial Modeler Language)을 이용하여 다양한 모델별 산림지역의 임상정보를 추출, 임상분류를 위한 모델링 기법을 개발하였다. 또한 l/5,000도엽을 기준으로 표본점을 배치하고 임상, 하층식생, 입지 및 토양에 대한 현지조사를 수행하였으며, 추출자료와의 상관성 분석 및 검증을 통하여 공간정보 기술을 이용한 산림정보 구축의 기반을 마련하고자 하였다.

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An Application Implementation for the SECS Protocol Communication between Equipments and a Host in a Semiconductor Process (반도체 제조 공정에서 장비와 호스트간 SECS 프로토콜 통신을 위한 응용 프로그램 구현)

  • 김대원;전정만;이병훈;김홍석;이호길
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.293-293
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    • 2000
  • The SECS(SEMI Equipment Communications Standard) is a standard protocol for communication between equipments and a host in semiconductor processes. This paper proposes the implementation of the HSMS(High-speed SECS Message Services) as an interface for transmission of the SECS messages and SECS-II containing message contents defined as an SEMI standard. The HSMS driver is implemented as a type of the daemon program and several DLL files. The SECS-II composes of the SML(SECS Message Language) file defining the SECS messages, the SML translator being able to interpret and transform the SML, and the data index table being able to refer to SECS messages. We also define the shared parameter to exchange the HSMS header and SECS message between the HSMS and the SECS-II. Eventually, to show the effectiveness of the proposed drivers, we test the SECS communications between equipments and a host using the implemented communication programs.

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ATC: An Image-based Atmospheric Correction Software in MATLAB and SML

  • Choi, Jae-Won;Won, Joong-Sun;Lee, Sa-Ro
    • Korean Journal of Remote Sensing
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    • v.24 no.5
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    • pp.417-425
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    • 2008
  • An image-based atmospheric correction software ATC is implemented using MATLAB and SML (Spatial Modeler Language in ERDAS IMAGINE), and it was tested using Landsat TM/ETM+ data. This ATC has two main functional modules, which are composed of a semiautomatic type and an automatic type. The semi-automatic functional module includes the Julian day (JD), Earth-Sun distance (ESD), solar zenith angle (SZA) and path radiance (PR), which are programmed as individual small functions. For the automatic functional module, these parameters are computed by using the header file of Landsat TM/ETM+. Three atmospheric correction algorithms are included: The apparent reflectance model (AR), one-percent dark object subtraction technique (DOS), and cosine approximation model (COST). The ACT is efficient as well as easy to use in a system with MATLAB and SML.

Inhibitory Effect of Scolopendra Morsitans L. Ether Extract on Lipopolysaccharide-Induced Inflammatory Response in RAW 264.7 Cells (오공(蜈蚣) 에테르 추출물의 RAW 264.7 cell에서 LPS로 유도된 염증반응 억제 효과)

  • Jung, Ho Kyung;Cho, Hyun Woo;Jung, Won Seok;Choi, In Young;Cho, Jung Hee;Jung, Su Young
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.27 no.1
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    • pp.78-82
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    • 2013
  • It has been reported that Scolopendra morsitans L.(SML) has beneficial effects on human health and diverse diseases. The purpose of this study was to investigate the anti-inflammatory effects of ether extract from Scolopendra morsitans L. on lipopolysaccharide(LPS)-induced inflammatory response. Thus, we examined the inhibitory effect of SML ether fraction on LPS-induced increase of inflammatory mediators(NO, iNOS, COX-2, and $I{\kappa}B{\alpha}$) and pro-inflammatory cytokines(TNF-${\alpha}$) in RAW 264.7 cells. In the present study, SML ether extract itself decreased cell viability in a dose dependent manner(> 100 ${\mu}g/ml$). In addition, LPS increased NO production, iNOS expression and phosphorylation of $I{\kappa}-B{\alpha}$, which were blocked by the treatment of SML ether fraction in a dose dependent manner. Furthermore, the treatment of LPS increased TNF-${\alpha}$ production. However, the pretreatment of SML ether fraction prevented the LPS-induced TNF-${\alpha}$ production in dose dependant manner. Taken together, our results suggest that SML may be a beneficial drug against inflammatory diseases such as sepsis.

Surface Composition and Molecular Diffusion on the Stability of Foams Formed from Protein/Surfactant Mixtures (단백질/계면활성제 혼합계에서 기포안정성에 대한 계면조성과 분자확산)

  • Park, Sun-Yeong;Kim, Myung-Soo;Jeong, Noh-Hee;Nam, Ki-Dae
    • Journal of the Korean Applied Science and Technology
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    • v.17 no.3
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    • pp.158-166
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    • 2000
  • A conductimetric study of foam formed from mixture of the protein, ${\beta}-lactoglobulin$, and the nonioinc surfactant, SML, revealed that their stability was reduced at concentrations of SML in the range $3{\sim}10mM$. The interaction of SML with ${\beta}-lactoglobulin$ was investigated by fluorimetry and a dissociation constant of $0.2{\mu}M$ was calculated for the complex. Surface tension studies confirmed the presence of interaction between the two components and provided evidence for the progressive displacement of ${\beta}-lactogloblin$ from the air/water interface with increasing SML concentration. Experiments using air-suspended microscopic thin liquid films revealed transitions in the chainage characteristics and thickness of the film at SML concentrations below that which resulted in destabilization of the foam. However, measurements of surface mobility of fluorescent-labeled ${\beta}-lactoglobulin$ by a photobleaching method identified that a transition to a mobile system occurred at a SML concentration which correlated with the onset of instability in the disperse phase. The results would indicate that maintenance of the viscoelastic properties of the surface is paramount importance in determining the stability of interfaces comprising mixtures of protein and surfactant.

Development of Analytical Method for Microplastics in Seawater (해수에 잔류하는 미세플라스틱의 정성정량 분석법 확립)

  • Chae, Doo-Hyun;Kim, In-Sung;Song, Young Kyoung;Kim, Sungwoo;Kim, Seung-Kyu
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.19 no.1
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    • pp.88-98
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    • 2014
  • Despite of emerging and increasing concerns to microplastics, no standard methodology has not been proposed for determination of microplastics. This study aims to develop the analysis method for microplastics in seawater by overviewing methodologies proposed by previous studies and by assessing some processes in those methodologies which possibly cause uncertainties in microplastic determination. Furthermore, we present preliminary results of distribution characteristics of microplastics in seawater of Incheon/Kyeonggi coastal region which is based on our new methodology. Microplastics in surface microlayer (SML) and subsurface water (SSW) were collected using mesh screen and planktonic nets (trawl net with $330{\mu}m$ mesh size and hand net with $20{\mu}m$ mesh size), respectively. Microplastics with < $300{\mu}m$ was predominant, indicating hand net as the better collection tool for SSW. As for SML, FT-IR based microplastic concentration was well matched with naked-eye based concentration which has been used in most of previous studies. However, a poor relationship was observed for SSW, indicating that concentration data of previous SSW studies should be corrected. Incheon/Kyeonggi bay seawater contained the similar concentration range with those in coastal region of the Nakdong River. Our methodology can be used as a basic tool for further microplatic studies.

Radicular Pain due to Subsidence of the Nitinol Shape Memory Loop for Stabilization after Lumbar Decompressive Laminectomy

  • Son, Byung-Chul;Kim, Deog-Ryeong
    • Journal of Korean Neurosurgical Society
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    • v.57 no.1
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    • pp.61-64
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    • 2015
  • A number of dynamic stabilization systems have been used to overcome the problems associated with spinal fusion with rigid fixation recently and the demand for an ideal dynamic stabilization system is greater for younger patients with multisegment disc degeneration. Nitinol, a shape memory alloy of nickel and titanium, is flexible at low temperatures and regains its original shape when heated, and the Nitinol shape memory loop (SML) implant has been used as a posterior tension band mostly in decompressive laminectomy cases because the Nitinol implant has various characteristics such as high elasticity and a tensile force, flexibility, and biological compatibility. The reported short-term outcomes of the application of SMLs as posterior column supporters in cervical and lumbar decompressive laminectomies seem to be positive, and complications are minimal except for the rare occurrence of pullout and fracture of the SML. However, there was no report of neurological complications related to neural compression in spite of the use of the loop of SML in the epidural space. The authors report a case of delayed development of radiating pain caused by subsidence of the SML resulting epidural compression.