• Title/Summary/Keyword: mAs

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Hydrothermal Synthesis of PZT Powders. (수열법에 의한 PZT분말 합성 연구)

  • 최승도;박병규
    • Korean Journal of Crystallography
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    • v.8 no.2
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    • pp.97-104
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    • 1997
  • Hydrothermal synthesis of PbZ1-xTixO3 has been investigated. Syntheses were performed using lead acetate triphdrate as Pb source, Ti/Zr gel by hydrolizing Ti-isopropoxide as Tiand Zr source and Zr-propoxide and KOH (0.5m, 1m, 2m) as mineralizer. The hydrothermal synthesis has been examined at 140℃, 150℃ and 160℃. Synthesized PZT powders showed a rectangular shape and were agglomerate. At 1m and 2m KOH concentrations PZT powders were synthesized the respective time of 8 hrs and 1hr but at 0.5m KOH concentration phase pure PZT powders were not synthesized for 5days reaction. At the conditions of low temperature and low KOH concentration unreacted Ti/Zr gel remained although synthesized powders were almost PZT. The size of PZT powders increased with KOH concentrations. PbO solid solutions were formed as intermediate phases and these were classified to PbO-10%TiO2 solid solution and PbO-3% TiO-3% TiO2 solid solution.

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A Study on Group Key Generation and Exchange using Hash Collision in M2M Communication Environment (M2M 통신 환경에서 해시 충돌을 이용한 그룹키 생성 및 교환 기법 연구)

  • Song, Jun-Ho;Kim, Sung-Soo;Jun, Moon-Seog
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.19 no.5
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    • pp.9-17
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    • 2019
  • As the IoT environment becomes more popular, the safety of the M2M environment, which establishes the communication environment between objects and objects without human intervention, becomes important. Due to the nature of the wireless communication environment, there is a possibility of exposure to security threats in various aspects such as data exposure, falsification, tampering, deletion and privacy, and secure communication security technology is considered as an important requirement. In this paper, we propose a new method for group key generation and exchange using trap hash collision hash in existing 'M2M communication environment' using hash collision, And a mechanism for confirming the authentication of the device and the gateway after the group key is generated. The proposed method has attack resistance such as spoofing attack, meson attack, and retransmission attack in the group communication section by using the specificity of the collision message and collision hash, and is a technique for proving safety against vulnerability of hash collision.

A Study of M2M Platform Technologies based on REST (REST 기반 M2M 플랫폼 기술 연구)

  • Lee, Chang-Yeol
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.9
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    • pp.4153-4159
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    • 2011
  • M2M can provide the bi-directional services between applications and objects which have the attached telecommunication module. It consists of the objects, platform, and (web based) applications. M2M can realize In-Transit Visibility and Asset Visibility combined with GIS. Although many applications of M2M, such as metering, monitoring, controlling, tracking et al., are being serviced, the interoperability among the M2Ms is not considered. In this paper, we described the interoperability. Specially, ROA, which is the state of art technology in mash-up, more than SOA, and URN, which is based on Open API in RESTful service, more than URL are studied. As the message protocol between platform and applications, MPM was defined.

Fabrication of dual wavelength photodetector using quantum well intermixing (다중양자우물의 상호 섞임 현상을 이용한 다중 파장 검출기의 제작)

  • 여덕호;윤경훈;김항로;김성준
    • Proceedings of the Optical Society of Korea Conference
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    • 2000.02a
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    • pp.10-11
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    • 2000
  • 광통신을 이용한 근거리 전송과 장거리 전송에서 1.3 및 1.55 $mu extrm{m}$ 파장 영역의 빛이 사용되고 있다. 향후, 각 가정마다 광선로를 연결하는 Fiber-to-the-home (FTTH)의 개념과 광CATV가 발전함에 따라 1.3 및 1.55 $\mu\textrm{m}$ 빛을 검출하는 소자와 송신하는 소자가 필요하게 된다. 본 논문에서는 이러한 다중파장을 검출할 수 있는 집적소자를 제작 및 측정하였다. 본 논문에서 사용된 epitaxial layer의 구조는 N-InP 기판 위에 1 $\mu\textrm{m}$의 n-InP buffer층, 5층의InGaAs/InGaAsP 다중양자우물과 0.2 $\mu\textrm{m}$ InGaAsP separate confinement heterostructure (SCH) 층, 0.5$\mu\textrm{m}$ InP clad층과 0.1 $\mu\textrm{m}$ InGaAs cap 층으로 구성되어있다. 모든 epi 층은 InP 기판에 격자 정합이 되어있다. 다중양자우물구조는 84 $\AA$의 InGaAs 우물층과 100 $\AA$의 InGaAsP 장벽층으로 구성되며, 상온에서 0.787 eV (1.575 $\mu\textrm{m}$)의 bandgap energy를 갖도록 설계하였다. (중략)

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Effect of L-Ascorbic Acid on Collagen Synthesis in 3T6 Fibroblasts and Primary Cultured Cells of Chondrocytes (3T6 세포주 및 연골 초대배양세포의 Collagen 합성에 미치는 비타민 C의 영향)

  • Kim, Mi-Hyang
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.1
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    • pp.42-47
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    • 2006
  • L-Ascorbic acid (AsA) is an essential nutrient for prevention of scurvy in humans, primates and guinea pigs that lack $L-gulono-\gamma-lactone$ oxidase which is required for the final step of AsA biosynthesis. AsA participates in various hydroxylation reactions involved in the biosynthesis of collagen. The purpose of this study is to clarify the role of AsA on collagen synthesis in 3T6 fibroblasts and primary cultured cells of chondrocytes. Cells were cultured in medium supplemented with catalase and AsA at various concentration. Supplement of AsA induced collagen synthesis in 3T6 fibroblasts and primary cultured cells of chondrocytes. The most remarkable induction of collagen synthesis by AsA was found in primary cultured chondrocytes. The content of collagen representing the amounts of extracellular matrix significantly increased in the cells of which growth was stimulated by AsA, while it decreased with increasing passage numbers of subculture in cells. It showed that the content of collagen decreased in the medium which contained AsA at the concentration higher than 5.0 mM. However, the contents of collagen to DNA were not different among various AsA concentrations. Supplementing with AsA resulted in enhancement of collagen formation and extracellular matrix. Therefore, there might be a Positive correlation between the activity of catalase and the AsA concentration. Moreover, it can be assumed that AsA stimulates the collagen synthesis by optimizing the cell-culture environment.

Holographic Data Grating Formation of AsGeSeS Single layer, Ag/AsGeSeS double layer And AsGeSeS/Ag/AsGeSeS Muti-layer Thin Films with the DPSS Laser (DPSS Laser에 의한 AsGeSeS,Ag/AsGeSeS 와 AsGeSeS/Ag/AsGeSeS 박막의 홀로그래픽 데이터 격자형성)

  • Koo, Yong-Woon;Koo, Sang-Mo;Cho, Won-Ju;Chung, Hong-Bay
    • Proceedings of the KIEE Conference
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    • 2006.10a
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    • pp.55-56
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    • 2006
  • We investigated the diffraction grating efficiency by the DPSS laser beam wavelength to improve the diffraction efficiency on AsGeSeS & Ag/ AsGeSeS thin film. Diffraction efficiency was obtained from DPSS(532nm)(P:P)polarized laser beam on AsGeSeS, Ag/ AsGeSeS and AsGeSeS/Ag/AsGeSeS thin films. As a result, for the laser beam intensity, 0.24 mW, single AsGeSeS thin film shows the highest value of 0.161% diffraction efficiency at 300 s and for 2.4 mW, it was recorded with the fastest speed of 50 s, which the diffraction grating forming speed is faster than that of 0.24 mW beam. Ag/ AsGeSeS and AsGeSeS/ Ag/ AsGeSeS multi-layered thin film also show the faster grating forming speed at 2.4 mW and higher value of diffraction efficiency at 0.24 mW.

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The Evaluation of Reconstruction Method Using Attenuation Correction Position Shifting in 3D PET/CT (PET/CT 3D 영상에서 감쇠보정 위치 변화 방법을 이용한 영상 재구성법의 평가)

  • Hong, Gun-Chul;Park, Sun-Myung;Jung, Eun-Kyung;Choi, Choon-Ki;Seok, Jae-Dong
    • The Korean Journal of Nuclear Medicine Technology
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    • v.14 no.2
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    • pp.172-176
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    • 2010
  • Purpose: The patients' moves occurred at PET/CT scan will cause the decline of correctness in results by resulting in inconsistency of Attenuation Correction (AC) and effecting on quantitative evaluation. This study has evaluated the utility of reconstruction method using AC position changing method when having inconsistency of AC depending on the position change of emission scan after transmission scan in obtaining PET/CT 3D image. Materials and Methods: We created 1 mL syringe injection space up to ${\pm}2$, 6, 10 cm toward x and y axis based on central point of polystyrene ($20{\times}20110$ cm) into GE Discovery STE16 equipment. After projection of syringe with $^{18}F$-FDG 5 kBq/mL, made an emission by changing the position and obtained the image by using AC depending on the position change. Reconstruction method is an iteration reconstruction method and is applied two times of iteration and 20 of subset, and for every emission data, decay correction depending on time pass is applied. Also, after setting ROI to the position of syringe, compared %Difference (%D) at each position to radioactivity concentrations (kBq/mL) and central point. Results: Radioactivity concentrations of central point of emission scan is 2.30 kBq/mL and is indicated as 1.95, 1.82 and 1.75 kBq/mL, relatively for +x axis, as 2.07, 1.75 and 1.65 kBq/mL for -x axis, as 2.07, 1.87 and 1.90 kBq/mL for +y axis and as 2.17, 1.85 and 1.67 kBq/mL for -y axis. Also, %D is yield as 15, 20, 23% for +x axis, as 9, 23, 28% for -x axis, as 12, 21, 20% for +y axis and as 8, 22, 29% for -y axis. When using AC position changing method, it is indicated as 2.00, 1.95 and 1.80 kBq/mL, relatively for +x axis, as 2.25, 2.15 and 1.90 kBq/mL for -x axis, as 2.07, 1.90 and 1.90 kBq/mL for +y axis, and as 2.10, 2.02, and 1.72 kBq/mL for -y axis. Also, %D is yield as 13, 15, 21% for +x axis, as 2, 6, 17% for -x axis, as 9, 17, 17% for +y axis, and as 8, 12, 25% for -y axis. Conclusion: When in inconsistency of AC, radioactivity concentrations for using AC position changing method increased average of 0.14, 0.03 kBq/mL at x, y axis and %D was improved 6.1, 4.2%. Also, it is indicated that the more far from the central point and the further position from the central point under the features that spatial resolution is lowered, the higher in lowering of radioactivity concentrations. However, since in actual clinic, attenuation degree increases more, it is considered that when in inconsistency, such tolerance will be increased. Therefore, at the lesion of the part where AC is not inconsistent, the tolerance of radioactivity concentrations will be reduced by applying AC position changing method.

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Agent "M" -The Apparatus of "Hate" and Human or Non-Human Beings as Living Dead (Agent "M" -'혐오'의 장치와 리빙 데드의 (비)인간)

  • Kwon, Doo-Hyun
    • Journal of Popular Narrative
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    • v.27 no.1
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    • pp.133-185
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    • 2021
  • This study is an attempt to connect television drama M, which deals with abortion issues, with theoretical focus such as materiality, relativity, and agency, to understand diffractively as an cartography of agential reality. According to Karen Barard's Agential Realism, Television drama M is a sociocultural phenomenon produced by the agential intra-actions of material-discursive apparatuses such as medical technology, ghost stories and legends, and male-affect. The 1990s repeatedly revealed "hate" through apparatuses such as technology, discourse, and affect, which are directed at women's gendered bodies. The material -discursive practice of plastic surgery and abortion proves that the agential reality surrounding the body is closely intertwined with medical technology, as well as with the genderized hate. Another related material-discursive phenomenon is rediscovery of the legend and fad of the ghost story, which is also produced from the hate of the denaturalized body, which is once again expanded and reproduced. Appearing in this environment of affect, M enacts diffraction, which is based on backlash, lacking posthuman implications for the materialization of the techno-body. M puts humanistic assumptions about "Man" as a universal definition, historically framed and defined in context. But it is not universal and it is gendered. The current time when the political turmoil surrounding medical technology, discourse, and bodily matters is violently intra-acted is the time to carefully account and respond to the alternative definitions of human beings that M has rejected.

Bioanalytical method validation for determination of arsenic speciation in dog plasma using HPLC-ICP/MS (Dog 혈장 중 HPLC-ICP/MS를 이용한 비소 화학종 분석법 검증)

  • Kim, Jong-Hwan;Kwon, Young Sang;Shin, Min-Chul;Kim, Su Jong;Seo, Jong-Su
    • Analytical Science and Technology
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    • v.29 no.5
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    • pp.234-241
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    • 2016
  • The approach presented in this article refers to the bioanalytical method validation for the detection and quantitative determination of arsenic species including arsenite (As(III)), arsenate (As(V)), dimethylarsinic acid (DMA) and monomethylarsonic acid (MMA) in dog plasma by high-performance liquid chromatography inductively coupled plasma mass spectrometry (HPLC-ICP/MS). The arsenic species were separated using an agilent As speciation column by a mobile phase of 2 mM sodium phosphate monobasic, 0.2 mM ethylenediaminetetraacetic acid disodium salt dehydrate, 10 mM sodium acetate, 3 mM sodium nitrate and 1 % ethyl alcohol at pH 11 (adjusted with 1M NaOH). The method validation experiment was obtained selectivity, linearity, accuracy, precision, matrix effect, recovery, system suitability, dilution integrity and various stabilities. All calibration curves showed good linearity (R2>0.999) within test ranges. The lower limit of quantitation (LLOQ) was 5 ng/mL for As(III), As(V) and DMA, and 20 ng/mL for MMA. The system suitability and dilution values were within 6.5 % and 7.7 %. Subsequently, the developed and validated HPLC-ICP/MS method was also successfully applied to determine the arsenic speciation in dog plasma samples, and the recoveries for the spiked samples were in the range of 91.5–102.2 %. Therefore, this method could be applied to the evaluation of arsenic exposure, health effect assessment and other bio-monitoring studies in biological samples.

A Study on Availability of AtoM for Recording Korean Wave Culture Contents : A Case of K-Food Contents (한류문화콘텐츠의 기록화를 위한 AtoM 활용 방안에 관한 연구 K-Food 콘텐츠를 중심으로)

  • Shim, Gab-yong;Yoo, Hyeon-Gyeong;Moon, Sang-Hoon;Lee, Youn-Yong;Lee, Jeong-Hyeon;Kim, Yong
    • The Korean Journal of Archival Studies
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    • no.43
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    • pp.5-42
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    • 2015
  • Korean wave 3.0 is focused on 'K-Culture' which includes traditional culture, cultural art as well as existing culture contents as a keyword. It considers everything about Korean culture as materials of Korean wave culture contents. Since Korean wave culture contents reflect contemporary social aspect, it needs to preserve those contents as archives and records which have the important value of evidence. With this social environment, this study aims to implement RMS based on AtoM that manages various kinds of Korean wave culture contents through analysis of management situation of those materials. Recently, it is in progress individually to manage them through organizations dealing with korean cultures such as K-Pop, K-Food, K-Movie. However, it has problems in accumulating information and reproducing high quality contents because of lack of coordination among organizations. To solve the problems, this study proposed RMS based on open source software Access to Memory(AtoM) for managing and recording Korean wave culture contents. AtoM provides various functions for managing records and archives such as accumulation, classification, description and browsing. Furthermore AtoM is for free as open source software and easy to implement and use. Thus, this study implemented RMS based on AtoM to methodically manage korean wave culture contents by functional requirements of RMS. Also, this study considered contents relating K-Food as an object to collect, classify, and describe. To describe it, this study selected ISAD(G) standard.