• Title/Summary/Keyword: 동안정성

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In-situ Measurements of the Stress in $TiO_2$ Thin Films ($TiO_2$ 박막의 두께에 따른 실시간 스트레스 측정에 관한 연구)

  • 한성홍
    • Korean Journal of Optics and Photonics
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    • v.4 no.3
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    • pp.260-265
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    • 1993
  • An in-situ stress measurement interferometer is constructed and used to measure the intrinsic stress in Ti$O_2$ thin films during their growth by ion-assisted deposition. It is found that the stress increases with the momentum transferred by the ion beam to the growing film and is fairly well agreed with Windischmann's model. The variation of the stress with thickness is qualitatively explained in terms of the balance between the compressive stress produced by the ion beam and the surface diffusion determined by the surface temperature.

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Efficient data allocation scheme for dependent items over multiple wireless broadcast channels (다중 무선 방송채널에서의 상호관련 데이터들을 위한 효율적인 데이터할당 방법)

  • Park, Sung-wook;Jung, Sungwon
    • Proceedings of the Korea Information Processing Society Conference
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    • 2007.11a
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    • pp.219-222
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    • 2007
  • 무선방송환경은 모바일 클라이언트의 수에 상관없이 다수의 클라이언트에게 데이터를 보낼 수 있다는 특징으로 인하여 많은 관심을 받아왔다. 그러나 기존 대부분의 연구는 한 개의 독립적인 데이터를 최단시간에 획득하는 것을 목표로 하였고, 질의어와 같이 상호 관련된 여러 데이터를 동시에 획득해야 하는 경우에 대한 연구는 미비했다. 또한 그러한 논문들에서도 질의어 내의 데이터들이 다른 채널상의 동일시간에 나타나지 않도록 할당하는 문제에 대해서만 연구되어 왔고 각 데이터의 요청빈도에 따른 데이터의 접근확률은 반영되지 않았다. 우리는 본 논문에서 이러한 데이터들을 채널에 할당하는 문제뿐만 아니라 여러 질의어에 포함되어 상대적으로 요청빈도가 높은 데이터들을 한 방송 사이클 동안 다중 채널상에 여러 번 할당되게 하여 해당 질의어에 속한 데이터들을 모두 획득하는데 요구되는 평균응답시간을 줄이는 새로운 방법을 제안한다.

Evaluation on the Improved Individual Training Account System of Korea (개선된 내일배움카드제훈련에 대한 평가)

  • Yoo, Kil-Sang
    • The Journal of Korean Institute for Practical Engineering Education
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    • v.4 no.1
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    • pp.140-145
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    • 2012
  • Korean government improved the Individual Training Account (ITA) System in September 15, 2011. This paper evaluated the Improved Individual Training Account System of Korea based on the success conditions of contracting-out public services. The results showed that the improved ITA system of Korea was expected to solve some of the problems of former ITA system of Korea by stabilizing ITA training market, improving target of ITA and better matching between jobs and training courses, and activating trainees. Nevertheless the improved ITA system of Korea still has some problems to be solved. The relationship between job placement services and issue of ITA should be closer by improving tailored total one-stop services for job seekers. The government should develop infrastructure for evaluating, monitoring and supporting the ITA training to enhance the effectiveness and efficiency of the ITA training system.

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Long-term Streamflow Prediction Using ESP and RDAPS Model (ESP와 RDAPS 수치예보를 이용한 장기유량예측)

  • Lee, Sang-Jin;Jeong, Chang-Sam;Kim, Joo-Cheol;Hwang, Man-Ha
    • Journal of Korea Water Resources Association
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    • v.44 no.12
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    • pp.967-974
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    • 2011
  • Based on daily time series from RDAPS numerical weather forecast, Streamflow prediction was simulated and the result of ESP analysis was implemented considering quantitative mid- and long-term forecast to compare the results and review applicability. The result of ESP, ESP considering quantitative weather forecast, and flow forecast from RDAPS numerical weather forecast were compared and analyzed with average observed streamflow in Guem River Basin. Through this process, the improvement effect per method was estimated. The result of ESP considering weather information was satisfactory relatively based on long-term flow forecast simulation result. Discrepancy ratio analysis for estimating accuracy of probability forecast had similar result. It is expected to simulate more accurate flow forecast for RDAPS numerical weather forecast with improved daily scenario including time resolution, which is able to accumulate 3 hours rainfall or continuous simulation estimation.

Effect of pH, Chemical Composition and Additives on Stability of Soymilk Suspension (pH, 화학적 조성 및 첨가제가 두유(豆乳)의 현탁안정성에 미치는 영향)

  • Kim, Eun-Soo;Chung, Seong-Soo;Jo, Jae-Sun
    • Korean Journal of Food Science and Technology
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    • v.22 no.3
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    • pp.319-324
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    • 1990
  • The effects of pH, protein and fat content, addition of emulsifiers, stabilizer, sugar, salt and calcium salt on the stability of soymilk suspension were investigated by analyzing the cream separated and precipitates of soymilk which is prepared by various conditions. In the alkaline region of pH, soymilk showed a good stability of the suspension and particularly, above pH 10, precipitates were not formed. When 1.5% of palm oil with 0.4% of glycerine monostearate was added to soymilk in the hydrophile-lipophile balance (HLB) value of 4 to 7, resulted maximal emulsion stability occured below H LB 6. The stability was decreased with increasing the fat concentration and soy oil showed better emulsion stability than that of palm oil. Among the commercial stabilizers, 0.03% of carrageenan was most effective. The stability was not decreased by addition of sugar up to 3% while it was decreased by addition of sodium salt and calcium salt at low level.

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Effect of Processing Conditions Upon Heat Stability and Structure Formation in Fish Protein (생선단백질의 열안정성과 조직형성속도에 공정조건이 미치는 영향)

  • Park, Sung-Jin;Kim, Byung-Yong
    • Korean Journal of Food Science and Technology
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    • v.24 no.5
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    • pp.463-469
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    • 1992
  • Effect of thermal processing upon the structure formation of surimi was investigated by differential scanning calorimeter (DSC), rigidity changes during heating, and scanning electron microscopy (SEM). DSC studies showed the transition temperatures and heat capacity of the proteins during heating. Thermal transition peaks of the proteins were shifted to the lower temperatures or disappeared by the addition of salt and higher heating rate or setting treatment ($4^{\circ}C$ or $40^{\circ}C$). Whereas setting at $4^{\circ}C$ for 24hr produced elastic component and showed a permanent effect in rigidity development during heating, setting at $40^{\circ}C$ for 30 min produced a temporary effect. SEM studies in conjunction with rigidity scanning provided an insight into the structural features of the gel and helped clarify the setting and protein modification effects.

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Effects of Ultrasonic Cleaning and Chemical Pre-treatment on the Characteristics of Fast-stabilized Rayon Fabrics (빠르게 안정화된 레이온직물의 특성에 미치는 초음파세척 및 화학전처리 영향)

  • Cho, Chae Wook;Cho, Donghwan
    • Journal of Adhesion and Interface
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    • v.14 no.3
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    • pp.146-159
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    • 2013
  • In the present study, stabilized rayon fabrics were prepared from fast isothermal stabilization processes, which were carried out within four minutes at $350^{\circ}C$. The effects of ultrasonic cleaning and chemical pre-treatment on the chemical composition, physical characteristics, X-ray diffraction pattern, thermal stability and shape of the stabilized rayon fabrics were investigated extensively. In order to reduce the weight loss and thermal shrinkage of rayon fabrics occurring during the stabilization process, ultrasonic cleaning was first conducted and then chemical pre-treatments using $NH_4Cl$, $Na_3PO_4$, $H_3PO_4$, and $ZnCl_2$ were performed, respectively. The results indicated that both ultrasonic cleaning and chemical pre-treatment influenced the weight loss, thermal shrinkage, microstructure, carbon content, thermal stability and fabric shape of stabilized rayon fabrics. Also the results depended on the fast-stabilization time and the type of chemical pre-treatment agents used.

A Qualitative Study of the Properties of the Korean Railway during the Japan Colonial Period (일제강점기의 우리나라 철도성격규명에 관한 정성적 연구)

  • Lee, Yong-Sang;Chung, Byung-Hyun
    • Journal of the Korean Society for Railway
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    • v.15 no.3
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    • pp.306-314
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    • 2012
  • At first, the railway was built mainly for military purposes by Japan. After the annexation by Japan, the Korean railway became a means of colonization for Japan but the railway also promoted modernization. As a new transportation medium, it influenced economic, cultural and social development. Until now, research identifying the properties of the railway in the Japanese colonial period has been insufficient. In particular, microscopic study of the influence of the railway on social change has been insufficient. In this study we investigated the properties of Japanese colonial period railway. This paper will help further to clarify the properties of the railway in the Japanese colonial period.

Classification of hysteretic loop feature for runoff generation through a unsupervised machine learning algorithm (비지도 기계학습을 통한 유출 발생 내 이력 현상 구분)

  • Lee, Eunhyung;Jeon, Hangtak;Kim, Dahong;Friday, Bassey Bassey;Kim, Sanghyun
    • Proceedings of the Korea Water Resources Association Conference
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    • 2022.05a
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    • pp.360-360
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    • 2022
  • 토양수분과 유출 간 관계를 정량화하는 것은 수문 기작 및 유출 발생 과정의 이해를 위한 중요한 정보를 제공한다. 특히, 유출과정의 특성화는 수문 사상에 따른 불포화대 내 토양수 및 토사 손실 제어와 산사태 및 비점오염원 발생 예측을 위해 필수적이다. 유출과정과 관련된 비선형성과 복잡성을 확인하기 위해 토양수분과 유출 사이의 이력 거동이 조사되었다. 특히, 수문 과정 내 이력 현상 구체화를 위해 정성적인 시각적 분류 및 정량적 평가를 위한 이력 지수들이 개발되었다. 정성적인 시각적 분류는 시간에 따라 시계 및 반시계방향으로 다중 루프 형상을 나누는 방식으로 진행되었고, 정량적 평가의 경우 이력 고리(Hysteretic loop) 내 상승 고리(Rising limb)와 하강 고리(Falling limb)의 차이를 기준으로 한 지수로 이력 현상을 특성화하였다. 이전에 제안된 방법론들은 연구자의 판단이 들어가기 때문에 보편적이지 않고 이력 현상을 개발된 지수에 맞춤에 따라 자료 손실이 나타나는 한계가 존재한다. 자료의 손실 없이 불포화대 내 발생 가능한 대표 이력 현상을 자동으로 추출하기 위해 적합한 비지도 학습기반 기계학습 방법론의 제안이 필요하다. 우리 연구에서는 국내 산지 사면에서 강우 사상 동안 다중 깊이(10, 30, 60cm)로 56개의 토양수분 측정지점에서 확보된 토양수분 시계열 자료와 산지 사면 내 위어를 통해 확보된 유출 시계열 자료를 사용하였다. 먼저, 기존에 분류 방법을 기반으로 계절 및 공간특성에 따라 지배적으로 발생하는 토양수분-유출 간 이력 현상을 특성화하였다. 다음으로, 토양수분-유출 간 이력 패턴을 자료 손실 없이 형상화하여 자동으로 데이터베이스화하는 알고리즘을 개발하였다. 마지막으로, 비지도 학습방법을 이용하여 데이터베이스화된 실제 발현 이력 현상 내 확률분포를 최대한 가깝게 추정하는 은닉층을 반복적인 재구성 학습을 통해 구현함으로써 대표 이력 현상 패턴을 추출하였다.

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Identifying the Causal Relationships of Appearance Management through an Analysis of One's Own Clothing and Wearing Experiences over a 10-day Period (10일 동안 선택한 자신의 의복 및 착용 경험의 분석을 통한 외모관리에 대한 관련성 연구)

  • Moody, Wendy;Kinderman, Peter;Sinha, Pammi;You, Kyung-Sook
    • Journal of the Korean Society of Clothing and Textiles
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    • v.33 no.6
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    • pp.841-852
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    • 2009
  • The aim of the study was to quantify and explore the causal relationships of appearance management through an analysis of one's own clothing and wearing experience, namely clothing preference, personality factors, emotion and mood, newness, familiarity of one's own clothing, and social interaction. Explorative quantitative and qualitative research was carried out using a uniformly composed sample of 10 size 12 females. A personality questionnaire was completed a short while prior to the study. A 10 day ‘wearing diary’ was administered to record where and when outfits were worn. Two questionnaires were completed measure emotion and mood, prior to changing into clothing (a daily baseline), and when they were wearing or changed clothing (dynamic mood). Qualitative information was recorded and included their thoughts and feelings other than the questionnaires, along with photographs that were taken by participants. Preference, social and newness ratings for each outfit worn were recorded after the 10 day period. SPSS analysis identified relationships and linear regression analysis identified preference indicators. Thematic analysis identified 9 themes regarding the management of mood, personality and social factors when wearing one's own clothing. The results indicated strong relationships between emotion, mood, personality and preference and how much newness and different levels of social interaction influence these factors. Participants tended to match their mood and personality with their clothing choices but in some cases also compensated. This research recognises the value of consumer psychological processes involved in appearance management, and has implications for further research into product involvement, post-purchase behaviour and retail strategies for personal shoppers.