• Title/Summary/Keyword: 3DEC

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A Study on Indoor Radon Concentrations in Seoul( I ) (서울 일부지역(一部地域)의 실내(室內) Radon 오염도(汚染度) 조사(調査) 연구(硏究)( I ))

  • Kim, Chang-Kyun
    • Journal of radiological science and technology
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    • v.19 no.1
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    • pp.51-54
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    • 1996
  • This study was conducted to find out the indoor radon concentrations from Jan. 1, to Dec. 31, 1995 in Seoul, and the following results were achieved; 1. The average concentration of indoor radon ranged from $0.51pCi/\ell$ to $0.78pCi/\ell$. 2. The correlation coefficients(r) of radon concentration and indoor meteorological conditions were as follows; 1) temperature : r=0.11 2) atmospheric pressure : r= -0.01 3) humidity : r=0.227.

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ZnO Thin Film Transistor Prepared from ALD with an Organic Gate Dielectric

  • Choi, Woon-Seop
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.543-545
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    • 2009
  • With injection-type source delivery system of atomic layer deposition (ALD), bottom-contact and bottom-gate thin-film transistors (TFTs) were fabricated with a poly-4-vinyphenol polymeric dielectric for the first time. The properties of the ZnO TFT were greatly influenced by the device structure and the process conditions. The zinc oxide TFTs exhibited a channel mobility of 0.43 $cm^2$/Vs, a threshold voltage of 0.85 V, a subthreshold slope of 3.30 V/dec, and an on-to-off current ratio of above $10^6$ with solid saturation.

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CAD 프레임워크 개념 및 기술동향

  • Lee, Mi-Seon;Son, Jin-U
    • Electronics and Telecommunications Trends
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    • v.6 no.3
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    • pp.187-202
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    • 1991
  • CAD 프레임워크는 다양한 CAD 툴들의 이용법을 사용자 관점에서 통합하여 사용의 편이성과 설계 작업의 생산성을 높이고 CAD 시스팀 관리의 효율성을 높이고자 창안된 개념이다. 본 고에서는 CAD 프레임워크의 개념과 기능, 구성과 DEC 의 Power Frame을 예로 한 프레임워크의 형태와 발전 현황, 그리고 표준화 동향과 제 4세대 프레임워크를 중심으로 한 앞으로의 전망에 대해 살펴본다.

Factors related to Health Promoting Behavior in Late School-age Children (학령기 후기 아동의 건강증진행위 관련요인)

  • Kim, Hyeon-Seop;Kim, Young-Im
    • Journal of the Korean Society of School Health
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    • v.23 no.1
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    • pp.1-10
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    • 2010
  • Purpose: The purpose of this study was to investigate factors influencing health promoting behavior of the late school age children and to analyze the difference of health promoting behavior according to personal factors of children. Methods: The subjects consisted of 169 school-aged children in the 6th grade in Gyeonggi-do. Data were collected from Dec. 1 to Dec. 10, 2008. The data were analyzed by using frequency, percentage, mean, standard deviation, t-test, ANOVA, Pearson's correlation coefficients and Stepwise multiple regression with the SPSS/WIN 12.0 program. Results: 1) Health promoting behavior was proved to be relatively high. The average item score for the health promoting behavior was $3.85{\pm}.41$. The highest degree of health promoting behavior was stress management (4.13). whereas the one with the lowest degree was exercise (3.40). 2) In the relationship between personal factors and health promoting behavior, there were statistically significant differences in gender, perceived health status, family mood, father's drinking habits, school performance, school satisfaction. 3) Health promoting behavior was showed significant positive correlations with perceived self-efficacy (r=.55), social support (r=.65), prior related behaviors (r=.44), perceived benefits of action (r=.42), and significant negative correlations with perceived barriers of action (r=-.37). 4) Stepwise multiple regression analysis was revealed that the most powerful predictor of health promoting behavior was social support ($\beta$=0.36) Conclusion: The combination of social support, perceived self-efficacy, perceived benefits of action, gender, and family mood accounted for 57.8% of the variance in the health promoting behavior of the late school age children.

Extensometers results correction in concrete dams: A case study in RCC Zhaveh Dam

  • Ziaei, Ahad;Ahangari, Kaveh;Moarefvand, Parviz;Mirzabozorg, Hasan
    • Structural Monitoring and Maintenance
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    • v.4 no.1
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    • pp.17-31
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    • 2017
  • Since extensometers are used to determine the absolute deformation of foundation and abutments and all results are obtained in reference to the base rod, the accuracy of these results has been constantly a subject of debate. In this regard, locating and installing extensometers outside the range of effect zone is also another challenge. The main purpose of this paper is to investigate and modify extensometers results based on the mentioned issues. For this aim, the concrete RCC Zhaveh dam in Iran was selected as the case study. To study the results of extensometers installed in this dam, first, the 3DEC_DP 5.00 software was applied for numerical modeling. Parameters such as discontinuities, dead load and piezometric pressure in the interface of concrete and rock were considered. Next, using the results obtained from 6 extensometers in foundation and abutments and 4 clinometers in dam body, the numerical model was calibrated through back analysis method. The results indicate that the base rod is moved and is not recommended being used as the base point. In other words, because installation of base anchor outside the range of effect zone is not possible due to the operational and economic considerations, the obtained results are not accurate enough. The results indicate a considerable 2-3 mm displacement of the base rod (location of the base anchor) in reference to the real zero point location, which must be added to the base rod results.

Comparative Analysis in Perception on Men's Fashion Using Big Data : Focused on Influence of COVID-19 (빅 데이터를 활용한 코로나19 이전과 이후의 남성 패션에 대한 인식 비교)

  • Kim, Do-Hyeon;Kim, Jeong-Mee
    • Journal of the Korea Fashion and Costume Design Association
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    • v.24 no.3
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    • pp.1-15
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    • 2022
  • The purpose of this study is to compare and analyze the perception of men's fashion before and after the COVID-19 pandemic. TEXTOM allowed the collection of Big Data based on the term 'men's fashion'. As for the data collection periods, Jan. 1, 2018 to Dec. 31, 2019 was set as the pre-COVID-19 era, while Jan. 1, 2020 to Dec. 31, 2021 was set as the post-COVID-19 era. The top 50 words in terms of appearance frequency were extracted from the data. The extracted words were processed using network centrality analysis and CONCOR analysis using Ucinet 6. Research findings were as follows. 1) In the pre-COVID-19 era, the appearance frequency of 'men' was the highest, followed by 'fashion', 'men's fashion', 'brand', 'daily look', 'suit', and 'department store'. These words came up with a high TF-IDF values. Network centrality analysis discovered that 'men', 'fashion', 'men's fashion', 'brand', and 'suit' had a high level of connectivity with other words. CONCOR analysis showed four significant groups: 'fashion item and styles', 'fashion show', 'purchase', and 'collection'. 2) In the post-COVID-19 era, the appearance frequency of 'men' was the highest, followed by 'fashion', 'brand', 'men's fashion', 'discount', 'women', and 'luxury'. These words also displayed high TF-IDF values. Network centrality analysis found that 'fashion', 'men', 'brand', 'men's fashion', and 'discount' had a high level of connectivity with other words. CONCOR analysis showed four significant groups: 'fashion item and style', 'fashion show', 'purchase', and 'situation'. 3) Before the outbreak of the pandemic, men were interested in suits to wear to the office, daily look, and fashion shows in Milan and Paris. They often purchased menswear in multi-brand and open stores. However, they were more interested in sneakers, casual styles, and online fashion shows as social distancing and working from home became common. Most purchased menswear through online platforms.

Electrochemical Characteristics of EDLC with various Organic Electrolytes (유기전해질에 따른 EDLC의 전기화학적 특성)

  • Yang Chun-Mo;Lee J.K.;Cho W.I.;Cho B.W.;Rim Byung-O
    • Journal of the Korean Electrochemical Society
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    • v.4 no.3
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    • pp.113-117
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    • 2001
  • Specific capacitance and charge-discharge rate of EDLC using activated carbon electrode were affected by the compositions of electrolytes, the conditions of charge-discharge and physical properties of activated carbon materials. The activated carbon electrode was prepared by dip coating method. Charge-discharge test and electrochemical experiments were carried out for various kinds of organic electrolytes. Effects of charge and discharge current density on the specific capacitance were studied. Characteristics of leakage current, self-discharge and time-voltage curves in optimum conditions of organic electrolytes were compared with conventional $1M-Et_4NBF_4/PC$ electrolyte. The EDLC using MSP-20(specific surface area: $2000m^2/g$) electrode and $1M-LiPF_6/PC-DEC(1:1)$ was exhibited th highest specific capacitance of 130F/g and low polarization resistances. The EDLC using MSP-20 electrode at $1M-LiPF_6/PC-DEC(1:1)$ was small leak current of 0.0004A for 15min, long voltage retention of 0.8V after 100h and linear time-voltage curves with small IR-drop.

Biodegradation Mechanism of Shogaol by Aspergillus niger (Aspergillus niger에 의한 Shogaol의 생분해 메카니즘)

  • 고인경;이상섭
    • YAKHAK HOEJI
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    • v.27 no.1
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    • pp.29-36
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    • 1983
  • Shogaol, one of the main pungent principles of the rhizome of Zingiber officinale, Roscoe, was biodegraded by Aspergillus niger to produce two main metabolites. The crystalline metabolite obtained after silicic acid column chromatography was proved to be 1-(4-hydroxy-3- methoxyphenyl)decan-10-ol-3-one. The oily metabolite obtained after prolonged fermentation was 1-(4-hydroxy-3-methoxyphenyl)-decan-3, 10-diol. The results suggest that shogaol should be biodegraded to 1-(4-hydroxy-3-methoxyphenyl)-dec-4-en-10-ol-3-one or to 1-(4-hydroxy-3-methoxyphenyl)-decan-3-one, and to 1-(4-hydroxy-3-methoxyphenyl)-decan-10-ol-3-one then to 1-(4-hydroxy-3-methoxyphenyl)-decan-3, 10-diol and finally to carbon dioxide and water.

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Numerical investigation of the impact of geological discontinuities on the propagation of ground vibrations

  • Haghnejad, Ali;Ahangari, Kaveh;Moarefvand, Parviz;Goshtasbi, Kamran
    • Geomechanics and Engineering
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    • v.14 no.6
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    • pp.545-552
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    • 2018
  • Blast-induced ground vibrations by a significant amount of explosives may cause many problems for mining slope stability. Geological discontinuities have a significant influence on the transmission of dynamic pressure of detonation and according to their position relative to the slope face may have damaging or useful impacts on the slope stability. In this study, the effect of geological discontinuities was investigated by modelling a slope with geological discontinuities through applying the dynamic pressure in three-dimensional discrete element code (3DEC). The geological discontinuities in four states that generally apperceived in mine slopes are considered. Given the advantages of the pressure decay function defined by some researcher, this type of function was used to develop the pressure-time profile. The peak particle velocities (PPV) values were monitored along an axis by utilization of Fish programming language and the results were used as an indicator to measure the effects. As shown in the discontinuity-free model, PPV empirical models are reliable in rocks lacking discontinuities or tightly jointed rock masses. According to the other results, the empirical models cannot be used for the case where the rock mass contains discontinuities with any direction or dip. With regard to PPVs, when the direction of discontinuities is opposite to that of the slope face, the dynamic pressure of detonation is significantly damped toward the slope direction at the surface of discontinuities. On the other hand, when the discontinuities are horizontal, the dynamic pressure of detonation affects the rock mass to a large distance.

Nutrition Survey of Children in A Kindergarten of a Private Elementary School in Pusan 1. A Study on Nutrient intake and Nutritional Status (부산시내 일부 사립국민학교 부속 유치원 어린이의 영양 실태에 관한 연구 1. 영양 섭취실태 및 건강실태 조사)

  • Kim, Kap-Soon;Lee, Sung-Ho;Chae, Ki-Su;Lim, Hyo-Jin
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.23 no.4
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    • pp.587-593
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    • 1994
  • A nutrition survey of 152 children , in the kindergarten attached to a proivate elimentary school of Pusan, was undertaken between Dec. 1 and Dec.14, 1993, to investigate dietary intake and nutrition status. The results are summarized as follows. 1) Compared with the Korean child development standard, their development conditions showed 113.1% , 102.2% , 103.3%, 101.75 in weight, height, head and chest, respectively. 2) By the standard of WLI(Weight Length Index) , proper to the children between age 4 and 6 , there proved to be 25% overweight and 4% obesity, 25% overweight and 19% obesity , 28 overweight and 26% obesity in 4-year-old, 5 year-old, and 6 -year-old children, respectively. 3) The children between age 4 and 6 averaged 37.6% in hematocrit and 12.4-12.8 5 in hemoglobin. these values were higher than those of the Korea child development standard. but the numbers of erythocyte, leucocyte and platelets were normal . Only a single child was considered suffering from aenmia . The 8% of them were over 200mg/이 in cholesterol, dangerously approaching the atherosclerosis. The 31% averaged 120mg/이 in triglyceride . And the 6% proved 100mg/이 in blood glucose when hung교. So it came out that not a few children had some factors dangers to diabetes, atherosclerosis and heart diseases : complications arising from obesity. 4) The intake of nutrients , except the 4-year-old children , ranged 108.4% to 2665 from the recommended value. The rates of carbohydrate, fat and protein to be much correlation among total intake of nutrients, development , results of blood test and WLI. The degree of obesity was proportionate to the intake of nutrients.

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