• 제목/요약/키워드: Poor Solution

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稀薄溶液에서의 Polymer의 機械的 切斷 (제3보). 混合溶媒의 영향 (Mechanical Degradation of Polymers in Dilute Solution (III). The Influence of the Mixed Solvents)

  • 원영무
    • 대한화학회지
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    • 제17권3호
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    • pp.207-212
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    • 1973
  • 毛細灌法을 利用하여 여러가지 混合溶媒系(dioxane-n-butanol, dioxane-sec-butanol, dioxane-ethyleneglycol, dioxane-kerosene)중에서 polyvinylacetate의 희박용액을 機械的으로 切斷하여 그 결과로 얻어진 平均切斷速度定數(k) 및 極限重合度(g)를 moleculare dimension이 동일한 조건하에서 比較검토하였다. 그 결과 k보다는 g의 값이 사용하는 solvent의 종류에 따라 크게 영향을 받음을 알았으며 이에 關하여 考察하였다.

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SOLUTION CHARACTERISTICS AND MEMBRANE FORMATION OF PARTIALLY IMIDIZED POLY (AMIC ACID)

  • Lee, Hyuck-Jai;Won, Jong-Ok;Park, Hyun-Chae;Lee, Hoo-Sung;Kang, Yong-Soo
    • 한국막학회:학술대회논문집
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    • 한국막학회 1999년도 The 7th Summer Workshop of the Membrane Society of Korea
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    • pp.83-86
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    • 1999
  • The imidization effect of a poly (amic acid) dope solution on membrane formation has been investigated. Poly (amic acid) solution in S-methyl-2-pyrrolidione hs been thermally imidized at $120^{\circ}C$ with different curing time and its degree of imidization was determined by infrared spectroscopy. The solution properties have been studied as a function of concentration and curing time by dynamic light scattering. The quality of a solvent was changed from good to poor with increasing imidization of poly(amic acid).The reduced polymer-solvent interaction diminishes the membrane formation time. The morphology of a membrane was able to be controlled by the characteristics of dope solution.

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만성 농흉에 대한 Modified Eloesser's Operation 과 그 의의 (Modified Eloesser's Operation and Its Result In Chronic Empuema with Poor General Condition or Chachecic State)

  • 최종범
    • Journal of Chest Surgery
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    • 제12권2호
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    • pp.82-88
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    • 1979
  • During the past 3 years, 15 patients who could not be anesthetized generally because of poor general condition or cachecic state, of 111 patients with empyema, have been treated with modified Eloesser`s operation under the local anesthesia with 2% procaine. There were 13 males and 2 females ranging from 21 years to 61 years of age. The etiology was tuberculosis [6 cases], pyogenic pneumonia [5 cases], lung abscess [1 case], post-trauma [2 cases] and malignancy[1 case]. " The over-all mortality rate was 6.7%[1 case] and cause of its death was poor oral feeding because of post-traumatic psychosis. Modified Eloesser`s operation was performed after closed tube thoracostomy and irrigation with 1% zephanon solution for over 2 weeks. And then the other operation was not performed and all patients except 1 case appeared good progression (Complete healing; 4 cases, Progressive healing 10 cases, death: 1 case).

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장미꽃 추출물에 의한 견직물의 염색성 (Dyeing Properties of Rose Flower Extracts on Silk Fabrics)

  • 남성우
    • 한국염색가공학회지
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    • 제16권6호
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    • pp.10-15
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    • 2004
  • The colorants were extracted from the flower leaf of rose using a buffer solution. Dyeing properties and the fastness of silk fabrics dyed with rose flower extracts were investigated. K/S values of dyed fabrics were increased as the concentration of rose flower extracts was increased. Optimum dyeing temperature of rose flower extracts was $30^{\circ}C$. Fastness were generally good except light fastness which was extremely poor.

WAVELETS ON THE UNIT INTERVAL WITH BOUNDARY TREATMENT

  • Kim, Dai-Gyoung
    • 대한수학회논문집
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    • 제12권2호
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    • pp.427-456
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    • 1997
  • This paper concerns constructing wavelet bases on the unit interval, where a new boundary treatment is provided to overcome certain drawbacks of eariler constructions. Wavelet expansions on the unit interval usually suffer from artificial boundary effects and poor convergence at the boundaries. Many researchers have suggested a solution to the drawbacks. From a practical point of view, their solutions also have a common disadvantage. This paper provides a new solution using biorthogonality near the boundaries, that avoids the disadvantage while preserving their advantages.

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고 신뢰성 ATS 개발에 관한 연구 (Researches for the Development of High Reliable ATS)

  • 양오;김민호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 하계학술대회 논문집 D
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    • pp.2883-2885
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    • 2000
  • ATS(Automatic Transfer Switch), the secondary power supply system prepared for' temporary power fail on main in KEPCO in industrial field or running a important system. is developed. In this development, we prove that the proposed system is safe with results in a few environment testing focused on a solution against a poor environment by making virtual environment for a solution on problems of system reliability to switch more safely.

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공과대학생의 수학 기초능력에 대한 실태 조사 및 개선 방안에 관한 연구 (Study on Survey and Improvement Approaches on Basic Mathematics Ability of Engineering College Students)

  • 김종화;조성의
    • 디지털산업정보학회논문지
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    • 제9권4호
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    • pp.111-118
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    • 2013
  • Today, universities in Korea give a great effort to complement basic college scholastic ability of freshman. Maybe it could be unnecessary effort from university. However, we cannot just leave students who have poor academic performance about 10 to 30% in a university. Universities have to prepare to solve this problem. Thus government and universities investigate a lot of efforts but there is no guarantee. As a result, e-learning could be the best solution to complement poor academic performance of freshman and it also could be the best way to reduce financial burden of university. So, many universities introduce e-learning system and they also support professors to make e-learning content. We need to promote content usage and to improve overall operations. In this paper, we discuss poor academic performance problems under the current middle and high school education systems and review approaches to solve these problems. From this analysis, we propose the design of an effective e-learning system and a method of operation to complement students who achieve poor academic performance.

Copper Electroplating on Mg Alloy in Pyrophosphate Solution

  • Van Phuong, Nguyen;Moon, Sungmo
    • 한국표면공학회:학술대회논문집
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    • 한국표면공학회 2016년도 추계학술대회 논문집
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    • pp.124.1-124.1
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    • 2016
  • In this work, uniform thickness and good adhesion of electrodeposited copper layer were achieved on AZ91 Mg alloy in alkaline noncyanide copper solution containing pyrophosphate ion by employing appropriate zincate pretreatment. Without zincate pretreatment, the electrodeposited copper layer on AZ91 Mg alloy was porous and showed poor adhesion which was explained by small number of nucleation sites of copper due to rapid dissolution of the magnesium substrate in the pyrophosphate solution. The zincate pretreatment was found as one of the most important steps that can form a conducting layer to cover AZ91 surface which decreased the dissolution rate of AZ91 Mg alloy about 40 times in the copper pyrophosphate solution. Electrodeposited copper layer on AZ91 Mg alloy after an appropriate zincate pretreatment showed good adhesion and uniform thickness with bright surface appearance, independent of the deposition time but the surface roughness of the electrodeposited copper layer increased with increasing Cu deposition time.

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Compensation for Liquid Crystal

  • Jea-Claude, Lehureau;Laure, Lee Mane Si
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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    • pp.1104-1107
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    • 2003
  • Normally white TN-LCD is the preferred solution in active matrix display thanks to easy production, fast response and good white balance. However, it is has poor viewing angle properties and correction films are difficult to design. We present the mathematics of designing a compensating film and discuss various technological solutions for making

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범용 데이터 셋과 얼굴 데이터 셋에 대한 초해상도 융합 기법 (Super Resolution Fusion Scheme for General- and Face Dataset)

  • 문준원;김재석
    • 한국멀티미디어학회논문지
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    • 제22권11호
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    • pp.1242-1250
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    • 2019
  • Super resolution technique aims to convert a low-resolution image with coarse details to a corresponding high-resolution image with refined details. In the past decades, the performance is greatly improved due to progress of deep learning models. However, universal solution for various objects is a still challenging issue. We observe that learning super resolution with a general dataset has poor performance on faces. In this paper, we propose a super resolution fusion scheme that works well for both general- and face datasets to achieve more universal solution. In addition, object-specific feature extractor is employed for better reconstruction performance. In our experiments, we compare our fusion image and super-resolved images from one- of the state-of-the-art deep learning models trained with DIV2K and FFHQ datasets. Quantitative and qualitative evaluates show that our fusion scheme successfully works well for both datasets. We expect our fusion scheme to be effective on other objects with poor performance and this will lead to universal solutions.