• Title/Summary/Keyword: '소수'

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Changes of Functional Properties of Acylated Fish Protein (Acyl화에 의한 어류 단백질의 이화학적 성질의 변화)

  • Bang, Chan-Sik;Kim, Ze-Uook
    • Applied Biological Chemistry
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    • v.33 no.1
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    • pp.52-61
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    • 1990
  • Fish protein was acylated with acetic anhydride(AA), succinic anhydride(SA) and maleic anhydride(MA) in order to improve the functional properties of the protein. The surface hydrophobicity and functional properties of protein were measured to study the relationship between them. It was found that the extented acylation of nucleophilic groups such as amino and sulfhydryl groups of the amino acid residues of fish protein was higher than other groups when acylated with AA, and the degree of acylation was 89.5 % for amino groups and 72.2 % for sulfhydryl groups. The surface hydrophobicity of fish protein was decreased by succinylation and maleylation, whereas acetylation caused tittle change. The acylated fish protein concentrate(FPC) showed higher surface hydrophobicity than the acylated fish myofibrilla protein(FMP). Acylation with AA, SA and MA of fish protein resulted in a significant increase in protein solubility, emulsifier properties, foaming properties, water adsorption capacity and oil adsorption capacity. These properties of acylated FMP were more improved than those of acylated FPC. Decrease in protein hydrophobicity was highly correlated with increase in protein solubility, and emulsifier properties and foaming properties were largely dependent on the solubility as well as surface hydrophobicity. The water adsorption capacity of the protein was significantly affected by solubility. Surface hydrophobicity had greater influence on oil adsorption capacity, whereas it had tittle effect on water adsorption capacity.

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The Financial Development of Korean Americans: A Comparison of Korean and Chinese American Banks in California (미국에서의 한인 금융: 캘리포니아에서 한국계와 중국계 은행의 비교)

  • Ahn, Hyeon-Hyo;Chung, Yun-Sun
    • Journal of the Korean association of regional geographers
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    • v.12 no.1
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    • pp.154-171
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    • 2006
  • By comparing to Chinese American banks, this research shows the uniqueness of Korean American banks. This article argues that instead of the cultural attributes and/or informal financial institutions, formal financial institutions, such as the ethnic banks studied here, are responsible for the business success of Asians abroad. However, ethnic banks have different development trajectories depending on their respective ethnic communities. Korean American banks are notably different from Chinese American banks in terms of growth, profitability, and banking strategies. Although both ethnic banks exercise relationship banking strategies in their loan portfolios, their deposit compositions are very different and cause significant differences in financial performance. The focus on business loans and high rates of non-interest deposits allow for higher growth rates in Korean American banks. Therefore, relationship banking does not adequately explain the differences of ethnic banks. This research attempts to understand the underlying factors in choosing banking strategies by mainly focusing on the unique examples found in Korean and Chinese immigrant societies. For Chinese Americans, the heterogeneity of their population composition and foreign influence dominate their bank structures. On the other hand, Korean American homogeneity and business orientation are distinctly different. The influence of Korean capital is not significant when compared to overseas Chinese capital.

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Effect of Alkyl Substituents, Surfactants, and Temperature on the Solubilization of 4-alkylaniline Derivatives by Cationic Surfactants (양이온계면활성제에 의한 4-알킬아닐린 유도체의 가용화에서 알킬치환기, 계면활성제 및 온도의 효과)

  • Lee, Dong-Cheol;Lee, Byung-Hwan
    • Journal of the Korean Applied Science and Technology
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    • v.37 no.2
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    • pp.250-259
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    • 2020
  • The solubilization constant (Ks) was determined by the UV-Vis method to investigate the interaction between organic matter (solubilized substance) and surfactant in solubilization. Solubilization constants and thermodynamic functions, according to the hydrophobic interaction between organic mater (4-alkylanilines with different alkyl substituent length) and cationic surfactants (DTAB, TTAB, and CTAB, having different hydrophobic lengths), were measured and calculated at various temperatures and compared with each other. As a result, the hydrophobic interactions between organic matters and cationic micelles increased with increasing the chain length of solute's substituent as well as surfactant's hydrophobe. However, the hydrophobic effect by the alkyl substituent of organic matter was greater than the hydrophobic effect by the surfactant. In addition, the results of the calculated thermodynamic functions showed that 4-alkylaniline was solubilized at the deep place in the micelle and its solubilization was greatly dependent on both the hydrophobic effects of organic matter and surfactant. At the calculated iso-structural temperature, the difference between the maximum and minimum values was less than 1K within the experimental conditions.

MCC 입자의 표면화학적 특성에 따른 부유부상 효과

  • 이학래;이진희;허용성;한신호;조중연
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • 2000.11a
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    • pp.41-41
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    • 2000
  • 부유부상 공정은 현재 신문고지와 사무용 고지의 탈묵을 통한 신문용지 및 화장지 제조 에 널리 사용되고 있는 고지재활용을 위한 핵심공정이다. 하지만 이들 공정은 갈수록 열악 해지는 국내 고지원료의 품질변화에 따라서 잉크 및 토너의 분리효율이 저하되고 있어 생산 되는 탈묵 펄프의 품질저하, 리젝트 발생량의 증대, 폐수 처리공정의 부하 증가 등 다양한 문제점을 발생시키고 있어 이에 대한 대책의 수립이 시급히 요청되고 있다. 현재와 같이 다양한 형태의 잉크 및 인쇄방식으로 인쇄된 많은 종류의 재활용지가 원료 로 투입되고 있는 경우 탈묵공정의 효율 향상을 위해서는 부유부상 공정에 대한 좀 더 체계 적이고 논리적인 접근이 필요하다. 이러한 문제점을 극복하기 위해 먼저 고지 재활용 공정 의 핵심 단위공정인 부유부상 공정에 관련된 복잡한 문제점을 단순화하여 고상 및 액상의 표면화학적 특성을 평가하고, 이에 따른 부유부상 공정의 효율을 분석하였다. 본 연구에서는 부유부상 공정을 기초과학적 측면에서 구명하기 위해 마이크로 크리스탈린 셀룰로오스(Microcrystalline cellulose: MCC)를 모델 물질로 사용하였고, 친수성 의 표면 특 성을 나타내는 MCC의 표면 특성을 바꾸기 위하여 AKD(alkyl ketene dimer)로 처리비율을 달리하여 사이징 처리하였다. 부유부상 실험에 사용된 MCC는 친수성을 띠는 것과 소수성 을 부여한 것을 구별하고 그 비율을 백색도를 통해 측정하기 위하여 자체적으로 친수성을 가지는 MCC는 세척 견뢰도가 높은 검은색 염료로 염색하였다. 준비된 친수성과 소수성 M MCC의 혼합비율 별로 패드를 작성하여 백색도를 측정함으로써 검량선을 작성하였다. 또한 부유부상 시간에 따른 제거효율을 알아보기 위하여 부유부상 시간별로 각각의 리젝트율과 수율올 측정하고, 리젝트 시료로부터 패드를 제조하여 백색도를 측정하였다. 실험 결과 소수성 MCC의 소수화 정도에 따라서 리젝트율이 증가하였으며, 이를 통해 표 면에 소수성을 띠는 입자는 소수성이 강할수록 부유부상공정에서 제거율이 증가한다는 것을 확인하였다. 부유부상 처리한 MCC로 패드를 제조한 뒤 백색도를 비교한 결과에서도 이를 확인하였다. 한편 리젝트로 함께 제거된 MCC 내에 존재하는 친수성 MCC의 양은 극히 미 세하였다. 또한 부유부상를 실시하는 초기에 상당량의 리젝트가 발생함을 확인하였는데, 이 는 전체 부유부상을 통해 제거되는 양의 45-68%였다. 한편 부유부상이 진행됨에 따라서 리젝트 양의 증가폭이 둔화되는 경향을 나타내었다. 이러한 경향은 MCC의 소수성이 강할 수록 더욱 뚜렷하게 나타났다. 이를 통해 계 내로부터 소수성인 물질이 급속하게 제거됨을 알 수 있었으며 필요 이상의 부유부상 처리는 잉크제거 효율을 높일 수는 있으나 소모되는 시간에 비하여 비효과적임을 알 수 있었다.

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A Study on the Learning-Teaching Plan about a Essential Concept of Decimal Fraction Based on Decimal Positional Notation (위치적 십진기수법을 본질로 하여 조직한 소수 개념 지도 방안 연구)

  • Kang, Heung-Kyu
    • Journal of Elementary Mathematics Education in Korea
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    • v.15 no.1
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    • pp.199-219
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    • 2011
  • In this thesis, we designed a experimental learning-teaching plan of 'decimal fraction concept' at the 4-th grade level. We rest our plan on two basic premises. One is the fact that a essential concept of decimal fraction is 'polynomial of which indeterminate is 10', and another is the fact that the origin of decimal fraction is successive measurement activities which improving accuracy through decimal partition of measuring unit. The main features of our experimental learning-teaching plan is as follows. Firstly, students can experience a operation which generate decimal unit system through decimal partitioning of measuring unit. Secondly, the decimal fraction expansion will be initially introduced and the complete representation of decimal fraction according to positional notation will follow. Thirdly, such various interpretations of decimal fraction as 3.751m, 3m+7dm+5cm+1mm, $(3+\frac{7}{10}+\frac{5}{100}+\frac{1}{1000})m$ and $\frac{3751}{1000}m$ will be handled. Fourthly, decimal fraction will not be introduced with 'unit decimal fraction' such as 0.1, 0.01, 0.001, ${\cdots}$ but with 'natural number+decimal fraction' such as 2.345. Fifthly, we arranged a numeration activity ruled by random unit system previous to formal representation ruled by decimal positional notation. A experimental learning-teaching plan which presented in this thesis must be examined through teaching experiment. It is necessary to successive research for this task.

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Social Capital and Overseas Chinese Economy: A Comparison of Korean and Chinese ethnobanks in California (사회자본과 화교경제: 캘리포니아주 한인 및 중국계은행의 비교를 중심으로)

  • Ahn, Hyeon-Hyo
    • Journal of the Economic Geographical Society of Korea
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    • v.13 no.4
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    • pp.641-662
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    • 2010
  • Through the comparative studies on Korean and Chinese ethnobanks in the U.S., this research finds the difference in the social capital between Korean and Chinese American economy and reinterprets the social capital in overseas Chinese. In many ethnic studies, the ethnobanks in the U.S. are thought as the main drive of the economic prosperity in the ethnic communities. For the success of these ethnobanks, the relationship banking of these ethnobanks are contrasted with the arms-length banking of the mainstream U.S. banks. However there are the differences both in performance and business strategies even among different ethnobanks. Contrary to the Korean ethnic banks having much portion of business loans, Chinese ethnic banks have stressed real-estate loans in their loan portfolio. This research regards the differences of business strategies and performance of these ethnobanks as the result of the different social, cultural contexts in each ethnic community. From these finings, we can improve the understanding of the concept of social capital in overseas Chinese economy.

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Real-Time Implementation of MPEG-1 Layer III Audio Decoder Using TMS320C6201 (TMS320C6201을 이용한 MPEG-1 Layer III 오디오 디코더의 실시간 구현)

  • 권홍석;김시호;배건성
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.25 no.8B
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    • pp.1460-1468
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    • 2000
  • The goal of this research is the real-time implementation of MPEG-1 Layer III audio decoder using the fixed-point digital signal processor of TMS320C6201 The main job for this work is twofold: one is to convert floating-point operation in the decoder into fixed-point operation while maintaining the high resolution, and the other is to optimize the program to make it run in real-time with memory size as small as possible. We, especially, devote much time to the descaling module in the decoder for conversion of floating-point operation into fixed-point operation with high accuracy. The inverse modified cosine transform(IMDCT) and synthesis polyphase filter bank modules are optimized in order to reduce the amount of computation and memory size. After the optimization process, in this paper, the implemented decoder uses about 26% of maximum computation capacity of TMS320C6201. The program memory, data ROM, data RAM used in the decoder are about 6.77kwords, 3.13 kwords and 9.94 kwords, respectively. Comparing the PCM output of fixed-point computation with that of floating-point computation, we achieve the signal-to-noise ratio of more than 60 dB. A real-time operation is demonstrated on the PC using the sound I/O and host communication functions in the EVM board.

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Sterilization effect of electrolyzed water and chlorine dioxide on Rubus coreanus Miquel (전기분해수와 이산화염소수 처리 복분자(Rubus coreanus Miquel)의 살균효과)

  • Teng, Hui;Kim, You Ho;Lee, Won Young
    • Food Science and Preservation
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    • v.20 no.4
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    • pp.459-466
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    • 2013
  • This study was carried out in order to investigate sterilization effect and to extend storage periods of the Rubus coreanus by treating with tap water (TW), electrolyzed water (EW) and aqueous chlorine dioxide ($ClO_2$). After each treatment plot was soaked with 10, 50, 100, 200 ppm in each sterilizing solution within 30 sec, each treatment was compared during the storage time at room temperature and refrigerator temperature. As results of total plate count according to temperatures and periods, the microbial sterilizing power of each treatment plot was bigger at EW and $ClO_2$ treatment plots than the TW treatment plot; however, it sharply increased on the high concentration $ClO_2$ treatment plot. Futhermore, the cold storage treatment plot had more outstanding microbial sterilizing power than the room temperature treatment plot. As a result of observing the surface of the Rubus coreanus using scanning electron microscope (SEM), no microbe was seen in EW and $ClO_2$ treatment plot. The results of measuring enzyme activity showed a more significant decrease in EW and $ClO_2$ solutions treatment plot than TW treatment plot but gradually increased with time. The contents of total polyphenol revealed similar values on each treatment. The EW and $ClO_2$ treatment of the Rubus coreanus could be considered as good methods for inhibiting microbial growth in fresh vegetables and fruit, thereby contributing to quality maintenance.

Cultural Diversity and Repression in Communities: A Study on China and Latin America (공동체에서의 문화 다양성과 억압 -중국과 라틴아메리카를 중심으로-)

  • Kim Dug-sam
    • Journal of the Daesoon Academy of Sciences
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    • v.44
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    • pp.177-212
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    • 2023
  • In this study, discussions of the suppression of cultural diversity in communities was conducted. First, based on the studies conducted so far and recent changes, the oppression that exists between the Chinese government and ethnic minorities was considered. The visible suppression mentioned was the expansion of Han Chinese Mandarin language education, sanctions on minority languages, and the expansion of higher education at the exclusion of minority identities. In terms of 'invisible' oppression, urbanization, urban development with modernization at the forefront, and the use of officials from minority ethnic groups educated by the central government were items that were discussed. Next, the case of Latin America was examined. In particular, attention was paid to the theory of resistance against Europeans and European culture. Based off of the worries and experiences of Latin American intellectuals who have underwent oppression as individuals from culturally diverse backgrounds, a mature theory was formulated that could be used to defend Chinese minorities in the future. There is a specificity to the problem of Chinese minority communities. However, from a large perspective, experience and self-critical exploration in Latin America serve as an opportunity to expand the specificity of Chinese minority communities. Their situation resembles previous situations in Latin America when native cultures were being culturally eroded by Europe. Thus, as Latin American scholars argue, a shift in perception is necessary. In addition to this, in the text, it is likewise necessary to reflect on diversity, freedom, and mutualistic respect. There are proposals advocating for the realization of Heyibutong (和而不同 harmony but not through sameness) based on the situation in China. In the process of this consideration, much thought was given about what the observed communities are like and what a hypothetically desirable community would be like. This extends not only to Chinese minority communities and native residents of Latin America, but also to Asians in the United States and foreigners in Korea. Through this, it is hoped that desirable communities characterized by cultural diversity can be skillfully pursued.

고분자 담체에 대한 혐기성 미생물의 초기부착에 관한 연구

  • 박성열;박영식;이승란;이창한;이송우;송승구
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • 2000.05a
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    • pp.206-207
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    • 2000
  • 고분자 담체의 경우 표면의 화학적 성질인 소수성과 물리적 성질인 표면거칠기는 미생물 부착과 관련이 있지만 두 요소 중, 표면거칠기의 영향이 더 크다고 볼 수 있으며 담체 표면의 소수성이 작고 표면거칠기가 클수록 혐기성 미생물이 잘 부착되었다.

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