• Title/Summary/Keyword: Ultra-high

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A Study on the Etching Mechanism of $(Ba, Sr)TiO_3$ thin Film by High Density $BCl_3/Cl_2/Ar$ Plasma ($BCl_3/Cl_2/Ar$ 고밀도 플라즈마에 의한 $(Ba, Sr)TiO_3$ 박막의 식각 메커니즘 연구)

  • Kim, Seung-Bum;Kim, Chang-Il
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.37 no.11
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    • pp.18-24
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    • 2000
  • (Ba,Sr)$TiO_3$ thin films have attracted great interest as new dielectric materials of capacitors for ultra-large-scale integrated dynamic random access memories (ULSI-DRAMs) such as 1 Gbit or 4 Gbit. In this study, inductively coupled $BCl_3/Cl_2/Ar$ plasmas was used to etch (Ba,Sr)$TiO_3$ thin films. RF power/dc bias voltage=600 W/-250 V and chamber pressure was 10 mTorr. The $Cl_2/(Cl_2+Ar)$ was fixed at 0.2 the (Ba,Sr)$TiO_3$ thin films were etched adding $BCl_3$. The highest (Ba,Sr)$TiO_3$ etch rate is $480{\AA}/min$ at 10 % $BCl_3$ to $Cl_2/Ar$. The change of Cl, B radical density measured by optical emission spectroscopy(OES) as a function of $BCl_3$ percentage in $Cl_2/Ar$. The highest Cl radical density was shown at the addition of 10% $BCl_3$ to $Cl_2/Ar$. To study on the surface reaction of (Ba, Sr)$TiO_3$ thin films was investigated by XPS analysis. Ion bombardment etching is necessary to break Ba-O bond and to remove $BaCl_2$. There is a little chemical reaction between Sr and Cl, but Sr is removed by physical sputtering. There is a chemical reaction between Ti and Cl, and $TiCl_4$ is removed with ease. The cross-sectional of (Ba,Sr)$TiO_3$ thin film was investigated by scanning electron microscopy (SEM), the etch slope is about 65~70$^{\circ}$.

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On-Road Investigation of PM Emissions of a City-Buses Fuelled by Diesel, CNG, and LPG Using a Mobile Emission Laboratory (이동형 배출가스 측정시스템(MEL)을 이용하여 디젤, CNG, LPG 시내버스에서 배출되는 입자상 물질 평가)

  • Lee, Seok-Hwan;Kim, Hong-Suk;Park, Jun-Hyuk;Yoon, Jun-Kyu
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.35 no.4
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    • pp.409-416
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    • 2011
  • A mobile emission laboratory (MEL) was designed to measure the amount of traffic pollutants with high temporal and spatial resolution under real conditions. Equipment for gas-phase measurements of quantity of CO, NOx, $CO_2$, and THC and for the measurement of the number density and size distribution of fine and ultra-fine particles by a FMPS and a CPC were placed in a mini-van. The exhaust of different type of vehicles can be sampled by MEL. This paper describes the construction and technical details of the MEL and presents data from the experiment in which a car chases city buses fuelled by diesel, CNG, and LPG. The diameters of most particles in the exhaust of the diesel city bus were less than 300 nm and most of the particles had a diameter of 30-60 nm. However, most particles in the exhaust of the CNG and LPG city buses were nanoparticles (diameter: less than 50 nm).

Triathlon-Related Overuse Injury and Medical Issues (트라이애슬론의 과사용 부상과 의학적 위험요인에 대한 고찰)

  • Park, Chan-Ho;Kwak, Yi-Sub;Kim, Tae-Un
    • Journal of Life Science
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    • v.20 no.2
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    • pp.314-320
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    • 2010
  • As the nature of triathlons is competition in three successive sports, triathletes experience elevated levels of stress on the body that are absent in single-sport athletic events, and consequently there are more potential medical problems to prepare for. Triathletes can also experience problems such as hypothermia, heat illness, excessive exposure to ultraviolet radiation, musculoskeletal injuries and trauma, immunosuppression, and haemolysis. Depending on the potentiality of such above-listed problems occurring in any given race, race organizers will prepare preventative measures and treatments accordingly. Olympic distance is not the only triathlon racing distance. Sprints, which are normally around half the Olympic distance, are common distances, as well as Long (2 km swim, 80 km bike, 20 km run), Ironman (3.8 km swim, 180 km bike, 42 km run), and ultra-distance events varying in length. Races of longer duration normally result in a higher percentage of athletes experiencing the above-mentioned medical problems, as well as inducing additional health risks such as hyponatraemia. Minimizing the occurrences of serious health issues is possible through the following means: carefully preparing for the probable race-day weather conditions; proper management and organization of the race; preparing an extensive water-safety and ground-course safety plan; distributing necessary nutrition along the course; and stressing the importance for athletes to have proper knowledge concerning race nutrition, biomechanical technique, physical preparation, and utilization of safe equipment. While risks of competing in triathlon are many, the instances of such medical problems are not excessive, and the triathlon has a reputation of being a reasonably safe sport as long as athletes with high risk take added precautions.

Studies on the Keeping Quality of Ultra-High-Temperature Sterilized Milk (초고온멸균유(超高溫滅菌乳)의 보존성(保存性)에 관한 연구(硏究))

  • Kim, Jong-U
    • Korean Journal of Agricultural Science
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    • v.9 no.2
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    • pp.556-561
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    • 1982
  • These studies were carried out to investigate the freshness and bacterial counts of ultrahigh- temperature sterilized market milk which were treated and distributed in three districts; Cheonan, Pyungtak and Suwon in Korea, and to elucidate theirs keeping qualities when stored in refregerator and at room temperature. And the results were obtained were as follows; 1. The acidities in milk from three plants after stored at $5^{\circ}C$ were retained 0.16% up to 6 weeks and 0.18% up to 10 weeks. And negative reactions were appeared for alcohol and boiling tests also up to 10 weeks. 2. After milk were stored at $25^{\circ}C$, the acidities were 0.18% up to 9 weeks and also negative reaction were appeared for both alcohol and boiling tests up to 9 weeks. 3. When milk were stored at $5^{\circ}C$, no thermoduric and coliform bacteria were detected from all samples. And the total viable number of organisms and the number of psychrophilic bacteria were $<10/m{\ell}$ for 5, 6, 7 and 10 weeks respectively. 4. Also thermoduric and coliform bacteria were not detected after milk were stored at $25^{\circ}C$ for 10 weeks. And the total viable number of organisms and the number of psychrophilic bacteria were $<10/m{\ell}$ after from 2 weeks to 10 weeks.

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Targeting Analysis of Lumenal Proteins of Chloroplast of Wheat using Proteomic Techniques

  • Kamal, Abu Hena Mostafa;Kim, Da-Eun;Oh, Myoung-Won;Chung, Keun-Yook;Cho, Yong-Gu;Kim, Hong-Sig;Song, Beom-Heon;Lee, Chul-Won;Uozumi, Nobuyuki;Choi, Jong-Soon;Cho, Kun;Woo, Sun-Hee
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2010.05a
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    • pp.14-14
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    • 2010
  • Plastid proteomics are essential organelles present in virtually all cells in plants and green algae. Plastids are responsible for the synthesis and storage of key molecules required for the basic architecture and functions of plant cells. The proteome of plastid, and in particular of chloroplast, have received significant amounts of attention in recent years. Various fractionation and mass spectrometry (MS) techniques have been applied to catalogue the chloroplast proteome and its sub-organelles compartments. To better understanding the function of the lumenal sub-organelles within the thylakoid network, we have carried out a systematical analysis and identification of the lumenal proteins in the thylakoid of wheat by using Tricine-SDS-PAGE, and LTQ-ESI-FTICR mass spectrometry followed by SWISS-PROT database searching. We isolation and fractionation these membrane from fully developed wheat leaves using a combination of differential and gradient centrifugation couple to high speed ultra-centrifuge. After collecting all proteins to eliminate possible same proteins, we estimated that there are 407 different proteins including chloroplast, chloroplast stroma, lumenal, and thylakoid membrane proteins excluding 20 proteins, which were identified in nucleus, cytoplasm and mitochondria. A combination of these three programs (PSORT, TargetP, TMHMM, and TOPPRED) was found to provide a useful tool for evaluating chloroplast localization, transit peptide, transmembranes, and also could reveal possible alternative processing sites and dual targeting. Finally, we report also sub-cellular location specific protein interaction network using Cytoscape software, which provides further insight into the biochemical pathways of photosynthesis. The present work helps understanding photosynthesis process in wheat at the molecular level and provides a new overview of the biochemical machinery of the thylakoid in wheat.

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A Feasibility Study on Application of a Deep Convolutional Neural Network for Automatic Rock Type Classification (자동 암종 분류를 위한 딥러닝 영상처리 기법의 적용성 검토 연구)

  • Pham, Chuyen;Shin, Hyu-Soung
    • Tunnel and Underground Space
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    • v.30 no.5
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    • pp.462-472
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    • 2020
  • Rock classification is fundamental discipline of exploring geological and geotechnical features in a site, which, however, may not be easy works because of high diversity of rock shape and color according to its origin, geological history and so on. With the great success of convolutional neural networks (CNN) in many different image-based classification tasks, there has been increasing interest in taking advantage of CNN to classify geological material. In this study, a feasibility of the deep CNN is investigated for automatically and accurately identifying rock types, focusing on the condition of various shapes and colors even in the same rock type. It can be further developed to a mobile application for assisting geologist in classifying rocks in fieldwork. The structure of CNN model used in this study is based on a deep residual neural network (ResNet), which is an ultra-deep CNN using in object detection and classification. The proposed CNN was trained on 10 typical rock types with an overall accuracy of 84% on the test set. The result demonstrates that the proposed approach is not only able to classify rock type using images, but also represents an improvement as taking highly diverse rock image dataset as input.

BS/channeling studies on the heteroepitaxially grown $Y_2O_3$ films on Si substrates by UHV-ICB deposition (실리콘 기판 위에 UHV-ICB 증착법으로 적층 성장된 $Y_2O_3$박막의 BS/channeling 연구)

  • 김효배;조만호;황보상우;최성창;최원국;오정아;송종한;황정남
    • Journal of the Korean Vacuum Society
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    • v.6 no.3
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    • pp.235-241
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    • 1997
  • The crystallinity and the structure of heteroepitaxially grown $Y_2O_3$ films on the silicon substrates deposited by Ultra High Vacuum Ionized Cluster Beam(UHV-ICB) were investigated by Back-scattering Spectroscopy(BS)/channeling. The channeling minimum values, $X_{min}$, of the $Y_2O_3$ films deposited by other methods were 0.8~0.95 up to the present, which indicates amorphous or highly polycrystalline nature of the $Y_2O_3$ films. On the contrary, the channeling minimum value of heteroepitaxially grown $Y_2O_3$ films on Si(100) and Si(111) deposited by UHV-ICB are 0.28 and 0.25 respectively. These results point out fairly good crystalline quality. It is also observed that the top region of $Y_2O_3$ films have less crystalline defects than the bottom region regardless of the crystal direction of the Si substrates. The axis of $Y_2O_3$<111> epitaxially grown on Si(111) is tilt by $0.1^{\circ}$ with respect to Si<111>. That of $Y_2O_3$<110> on Si(100) is parallel to the Si<001>. The $Y_2O_3$ film on Si(100) grew with single domain structure and that on Si(111) grew with double domain structure. From the result of oxygen resonance BS/channeling, the oxygen atoms in heteroepitaxially grown $Y_2O_3$ film on Si(111) substrate have the crystallinity, but that on Si(100) shows almost channeling amorphous state.

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The Study on Weldability of Boron Steel and Hot-Stamped Steel by Using Laser Heat Source (I) - Laser Weldability of Al-Si Coated Boron Steel Used for Hot Stamping Process - (레이저 열원을 이용한 보론강 및 핫스탬핑강의 용접특성에 관한 연구 (I) - 핫스탬핑 공정에 사용되는 Al-Si 코팅된 보론강의 레이저 용접특성 -)

  • Kim, Jong Do;Choi, So Young;Lee, Su Jin;Suh, Jeong
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.38 no.12
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    • pp.1367-1372
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    • 2014
  • As the awareness of the environmental crisis has recently increased around the world, numerous studies in the transport industry have been conducted to solve this problem through lightweight car bodies. The hot-stamping process has been presented as solution to achieve a light weight. Hot-stamping is a method that is used to obtain ultra-high strength steel (1,500 MPa or greater) by simultaneously forming and cooling boron steel in a press die after heating it to a temperature of $900^{\circ}C$ or above. This study involved a, fundamental examination of laser parameters to investigate the laser weldability of boron steel. As a result, the following optimum parameters for the shielding gas were found: Q = 20 l/min, ${\alpha}=40^{\circ}$, d = 20mm, and l = 0 mm. The hardness of butt weldment increasesed sharply as a result of martensite formation at the fusion zone.

A study on the EMI in special power distribution zone on ship (선내 특별 전원 분배구역의 EMI에 관한 연구)

  • Park, Jong-Sung;Choi, Gi-Do;Kim, Jong-Woo;Cho, Hyung-Rae
    • Journal of Advanced Marine Engineering and Technology
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    • v.38 no.6
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    • pp.730-736
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    • 2014
  • Test standards for electrical and electronic equipment required for ship operations is applying the IEC-60533 standard. However, although a test procedure and a specified regulation are clearly defined in the deck and bridge zone and general power distribution zone, they are not regulated in the special power distribution zone with ship propulsion system. For these reasons, the costs for additional research and development have been invested. In this paper, we was measured power noise in a special power distribution zone in ship and we were compared and analyzed values measured. The actual experiments are performed on the ship of Korea Maritime and Ocean University. As a result, the acquired data on Hanbada shows that loop antenna with low frequency band(160kHz) and ultra log antenna with high frequency band(1.97GHz)occur about 6-8dB differences and about 8.7 difference respectively. Also, the acquired data on Hannara shows that each loop antenna of 1MHz, 11MHz, and 25MHz occurs about 7dB difference about 4-5dB differences respectively. so standard of Special distribution zone must be specified by comparative analysis of data obtained by the experiment more.

Highly Sensitive Detection of Pathogenic Bacteria Using PDMS Micro Chip Containing Glass Bead (유리비드를 포함한 PDMS 마이크로칩을 이용한 고감도 감염성 병원균 측정에 관한 연구)

  • Won, Ji-Yeong;Min, Jun-Hong
    • KSBB Journal
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    • v.24 no.5
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    • pp.432-438
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    • 2009
  • Here, we demonstrated simple nucleic acid, RNA, concentration method using polymer micro chip containing glass bead ($100\;{\mu}m$). Polymer micro chip was fabricated by PDMS ($1.5\;cm\;{\times}\;1.5\;cm$, $100\;{\mu}m$ in the height) including pillar structure ($160\;{\mu}m\;(I)\;{\times}\;80\;{\mu}m\;(w)\;{\times}\;100\;{\mu}m\;(h)$, gap size $50\;{\mu}m$) for blocking micro bead. RNA could be adsorbed on micro glass bead at low pH by hydrogen bonding whereas RNA was released at high pH by electrostatic force between silica surface and RNA. Amount of glass beads and flow rate were optimized in aspects of adsorption and desorption of RNA. Adsorption and desorption rate was measured with real time PCR. This concentrated RNA was applied to amplification micro chip in which NASBA (Nucleic Acid Sequence Based Amplification) was performed. As a result, E.coli O157 : H7 in the concentration of 10 c.f.u./10 mL was successfully detected by these serial processes (concentration and amplification) with polymer micro chips. It implies this simple concentration method using polymer micro chip can be directly applied to ultra sensitive method to measure viable bacteria and virus in clinical samples as well as environmental samples.