• Title/Summary/Keyword: DPT

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Oxidation/Reduction Effect on Dielectric Properties of Sr1-xBaxNb2O6 (Sr1-xBaxNb2O6의 유전 특성에 대한 산화/환원 열처리의 영향)

  • Kang, Bong-Hoon;Paek, Young-Sop;Joo, Gi-Tae
    • Journal of the Korean Ceramic Society
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    • v.43 no.3 s.286
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    • pp.173-176
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    • 2006
  • ${Sr_{1-x}Ba_xNb_2O_6$(SBN) have been obtained in Pt crucible by melting and cooling in air atmosphere. Some SBNs being at the bottom of the crucible are black and transparent, and the other SBNs colorless. The black SBN became to be colorless by oxidation heat treatment $1,300^{\circ}C$ for 4 h, Curie temperature is changed by colorless change of black SBN. The reason seems to be $Nb^{5+}$ oxidation of some $Nb^{4+}$ ions in SBN or effect of unknown impurities. Diffused Phase Transition (DPT) was appeared during heating and cooling process. Various sintered SBN ceramics specimen showed relaxor characteristics.

A Study on the Synthesis of 1,3,5,7-Tetranitro-1,3,5,7-tetraazacyclooctane (1,3,5,7-Tetranitro-1,3,5,7-tetraazacyclooctane의 합성연구에 대한 고찰)

  • J. B. Kang;B. T. Koo;S. K. Lee;K. H. Lee;D. Y. Oh
    • Journal of the Korean Chemical Society
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    • v.24 no.4
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    • pp.322-328
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    • 1980
  • 1,3,5,7-Tetranitro-1,3,5,7-tetraazacyclooctane (homocyclonite) is prepared simultaneously with 1,3,5-trinitro-1,3,5-triazacyclohexane (cyclonite) by nitrolysis of hexamethylenetetramine. The purpose of our study was to detect the existence of intermediate, 1,5-endomethylene-3,7-dinitro-1,3,5,7-tetraazacyclooctane (DPT), by liquid chromatography based on the reaction mechanism, to derive the theoretical equation which is determinated by the ratio of total methylene group vs. amino N, for the proper quantity of paraformaldehyde added in the reaction and to obtain the optimum condition for maximum yield and purity by comparing the experimental results with the theoretical equation.

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Numerical Study on the Evaporation Flow Phenomena of Natural Refrigerant CO2 through Small Diameter Tubes (천연냉매인 이산화탄소의 세관 유동시 발생하는 증발 유동 현상에 대한 수치해석 연구)

  • Choi, In-Su;Park, Byung-Duck
    • Journal of the Korean Society of Industry Convergence
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    • v.10 no.2
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    • pp.89-96
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    • 2007
  • For the environment protection, carbon dioxide as a natural refrigerant has been studied to use in an automotive air conditioning system. Hence, a numerical model has been developed to describe the evaporation phenomena of carbon dioxide flowing through very small diameter tubes. The two dimensional low-Reynolds $k-{\varepsilon}$ model was used to predict the flow phenomena of carbon dioxide in the two phase during its evaporation. Furthermore, the results obtained from the model were compared with the experiments for the validation. The heat transfer coefficient is lower, as the tube inner diameter becomes smaller. However, the amount of heat absorbed by a unit mass of carbon dioxide is greater due to more surface area. Therefore, the small diameter tube has advantage in terms of compact design of evaporator. When the inlet condition of pressure and temperature is low, the heat transfer coefficient is slightly high at the same size of tube because of the thermal properties of carbon dioxide.

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A Study on Sizing System for Middle Aged Men (중년 남성의 치수 체계에 관한 연구)

  • Sung Ok-jin;Yang Chung-eun
    • Journal of the Korean Society of Clothing and Textiles
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    • v.29 no.6
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    • pp.764-771
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    • 2005
  • This study is to increase the efficiency for the suitability of clothing measurement and the production utility factors by setting up the measurement system with middle-aged men's physical characteristics. For this purpose this study measured the body sizes of middle-aged men and analyzed basic sizing items such as drop, height, and bust according to the ISO and KS systems and classified these sizes based on body shapes and heights. As a result, an internationally-compatible measuring system is presented in this study. The most common body shapes are portly (Drop 6) and regular (Drop 12) types and these two types form $74.7\%$. The height of 164cm$(31.2\%)$ and 170cm$(38.2\%)$ cover $69.4\%$; and the most general sizes of busts are 92, 96 and 100 and these sizes occupy $74.7\%$. In consideration of the ranges of height and bust, the general sizes (7 regular types and 9 portly types) are selected to present the standardized measurements; the mark for the top is height-bust-waist and the mark for the bottom is stature-waist-hip.

Ferroelectric Properties and DPT in the Perovskite PMT-PT System (Perovskite PMT-PT계의 강유전 특성 및 확산상전이)

  • Kim, Y.J.
    • Journal of the Korean Vacuum Society
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    • v.17 no.2
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    • pp.122-129
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    • 2008
  • Ferroelectric properties of the PMT-PT were also studied from the temperature dependence of hysteresis loops using a method slightly modified from Sawyer-Tower's. Dielectric, pyroelectric and piezoelectric properties of the ceramics in the system PMT-PT were investigated. The resulted densities of the PMT-PT ceramics system were greater than 97 % of the theoretical value. As observed SEM micrograph of the fracture surfaces of the PMT-PT ceramics system, the average grain sizes were increased about 3-5 ${\mu}m$ to 6-8 ${\mu}m$ with increasing sintering temperature. The specimens with PT<0.30 for PMT-PT solid solution system exhibited the dielectric and pyroelectric properties of a typical relaxor ferroelectrics. The composition with the maximum dielectric constant exhibits relatively superior pyroelectric and piezoelectric properties.

The Employment Status and Household Economic Life of the Elderly in Ulsan (울산 거주 노인의 취업유무와 가계경제생활)

  • Seo, Jung-Hee;Huh, Eun-Jeong
    • Korean Journal of Human Ecology
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    • v.17 no.5
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    • pp.939-950
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    • 2008
  • The purposes of this study are 1) to investigate the employment status of the elderly(i.e., whether the elderly is employed or not) in Ulsan, 2) to analyze the differences in household economic life between employed and unemployed old People, and 3) only for the employed old people, to compare the monthly earnings and job satisfaction by the work time of per day and by the regular employee or temporary employee. for this study, semi-structural questionnaires were distributed to 500 old people in Ulsan, in September, 2006. The results indicated that only 25% of the respondents were employed, and the employment status of the elderly was related to sex, age, education level, marital status, household composition, number of dwelling persons, and number of children. for household economic life, employed old people had higher household income and monthly allowances than unemployed old people, while they spent more on clothing, but less on food than unemployed old people. Regular old employees had higher monthly earnings and job satisfaction than temporary old employees. And the old employees working for more than 8 hours per day had higher monthly earnings than those working for less than 8 hours, but there was no significant difference in job satisfaction between the two groups.

Development of alcohol gas sensors measurable at room temperature (상온에서 측정 가능한 음주 측정용 알코올 가스 센서)

  • Jeon, Byung-Hyun;Lee, Ju-Hyuk;Kim, Seong-Jean;Lee, Cheol-Jin;Choi, Bok-Gil
    • Proceedings of the KIEE Conference
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    • 1999.07g
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    • pp.3265-3267
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    • 1999
  • Capacitance-type alcohol gas sensors using porous silicon (PS) layer as sensitive film were fabricated to measure low alcohol gas concentration. Though sensors using porous silicon layer have show high sensitivity by large internal surface area, there is still much room for improvement to measure low breath alcohol concentration especially at room temperature. In this work, to discuss the response properties against exposure to organic vapor for breath alcohol measurements on the basis of experimental results. we measured the variation of the capacitance for the range of 0 to 0.5% alcohol concentration, and observed the improvement of sensitivity by illumination of UV light. In addition, the effect of CO2 and N2 gases involved commonly in exhaling breath was estimated, and the same procedure against methanol vapor was executed to compare qualitatively with the capacitance characteristics by alcohol vapor.

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Performance Analysis of Anomaly Area Segmentation in Industrial Products Based on Self-Attention Deep Learning Model (Self-Attention 딥러닝 모델 기반 산업 제품의 이상 영역 분할 성능 분석)

  • Changjoon Park;Namjung Kim;Junhwi Park;Jaehyun Lee;Jeonghwan Gwak
    • Proceedings of the Korean Society of Computer Information Conference
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    • 2024.01a
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    • pp.45-46
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    • 2024
  • 본 논문에서는 Self-Attention 기반 딥러닝 기법인 Dense Prediction Transformer(DPT) 모델을 MVTec Anomaly Detection(MVTec AD) 데이터셋에 적용하여 실제 산업 제품 이미지 내 이상 부분을 분할하는 연구를 진행하였다. DPT 모델의 적용을 통해 기존 Convolutional Neural Network(CNN) 기반 이상 탐지기법의 한계점인 지역적 Feature 추출 및 고정된 수용영역으로 인한 문제를 개선하였으며, 실제 산업 제품 데이터에서의 이상 분할 시 기존 주력 기법인 U-Net의 구조를 적용한 최고 성능의 모델보다 1.14%만큼의 성능 향상을 보임에 따라 Self-Attention 기반 딥러닝 기법의 적용이 산업 제품 이상 분할에 효과적임을 입증하였다.

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A Comparative Study of Childhood Immunizational Level between Urban and Rural Areas (도시(都市)와 농촌지역(農村地域)의 영유아 예방접종률(豫防接種率) 비교조사(比較調査))

  • Park, Jung-Han;Kim, Jung-Nam;Woo, Kuck-Hyeun
    • Journal of Preventive Medicine and Public Health
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    • v.18 no.1
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    • pp.137-147
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    • 1985
  • To assess the childhood immunization level of urban and rural areas, 250 mothers of $6{\sim}23$ months old children residing in Namsan 1 Dong, Taegu, and 264 mothers of the same age children residing in five areas of Kyungsan Gun where community health practitioners are assigned were interviewed in March, 1984. Immunization rate for BCG was 98.0% in urban area and 95.8% in rural area. Among children who had BCG vaccination 91.4% of them were immunized within 1 month after birth in urban area and 88.1% in rural area. The percentage of children who received three doses of DPT vaccine was 83.2% in urban, and 87.5% in rural area ana that for the polio vaccine was 80.8% in urban and 87.9% in rural area. Only a few children have never been immunized with either BCG or DPT or polio vaccine. Overall immunization rate for measles was 64.4% in urban area while it was 55.3% in rural area and that for mumps and rubella was 50.4% in urban area as compared with 36.0% in rural area. However, among children of 15 months old and above the percentage of measles vaccination was 85.3% in urban area and 73.7% in rural area. Mumps and rubella vaccination rate was 77.6% in urban area and 62.4% in rural area. These differences in measles, mumps and rubella vaccination rates between urban and rural areas were statistically significant (p<0.05). Such findings as improved immunization level, no significant differences in BCG, DPT and polio vaccination rate between urban and rural areas, and fewer mothers in rural area have not vaccinated their children than mothers in urban area because of their ignorance may be attributed to the general improvement of living standard and implementation of the maternal and child health services of the government. Nevertheless many of the mothers in rural as well as urban area have not immunized their children on time and measles, mumps and rubella vaccination rates are substantially lower than other childhood immunizations. Future immunization activity should be geared to reinforcing these areas.

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EIC integrated DCS with single console

  • Kawahara, Hiroshi;Hwa, Hong-Tae
    • 제어로봇시스템학회:학술대회논문집
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    • 1988.10b
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    • pp.928-933
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    • 1988
  • Control technology has been making remarkable progress in electrical control (E), instrumentation & control (I) and computer control (C) field respectively. In order to rationalize system engineering and simplify system configuration and operation work, so called, EIC are now to be integrated into one system. FUJI has developed it's own E, I&C integrated system, to meet above mentioned market requirements of variety. This paper describes basic concept of FUJI's Integrated Man-Machine Interface, hereinafter called SINGLE CONSOLE, from some view points of E, I, C integration technology.

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