• Title/Summary/Keyword: 공통현상

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Synthesis and Properties of Liquid Crystal Compounds and Epoxy Resin Based Side Chain Liquid Crystal Polymers I. Low Molecular Weight Liquid Crystal Compounds (방향족 액정동족체 및 Epoxy형 측쇄 액정고분자의 합성 및 성질 I. 저분자 액정 동족체)

  • Park, Se Kwang;Ahn, Wonsool;Keum, Chang Dae;Park, Lee Soon
    • Applied Chemistry for Engineering
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    • v.9 no.1
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    • pp.66-70
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    • 1998
  • Several liquid crystalline monomers were synthesized and characterized to utilize as new matrix materials of liquid crystal/polymer composite films for display application. Liquid crystalline compounds which have azo group as center link, cyano group at one of the terminal position in common and bromoalkyl(azo(n)), azidoalkyl(AZI(n)), aminoalkyl(ALC(n)) as the terminal group were synthesized and identified respectively by FT-lR, $^1H-NMR$ spectrometer and elemental analysis. All these compounds exhibited nematic liquid crystalline region in the certain temperature range as determined by DSC and polarized optical microscope. These liquid crystalline compounds also showed a typical even-odd effect in both $T_{KN}$ and $T_{NI}$ due to conformational change as the length of terminal alkyl chain, $-(CH_2)n-$. was varied.

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Pathology and Classification of Focal Segmental Glomerulosclerosis (초점성 분절성 사구체 경화증의 병리와 분류)

  • Kim, Yong-Jin
    • Childhood Kidney Diseases
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    • v.16 no.1
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    • pp.21-31
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    • 2012
  • Focal segmental glomerulosclerosis (FSGS) is the name of the primary glomerular disease as well as the terminology to describe the secondary phenomena of any other glomerular diseases. It is characterized by sclerosis, hyalinosis, foam cell infiltration, vacuolar change of podocytes, and halo formation in the glomerulus. Throughout the interstitium, lymphocytes infiltration, tubular atrophy and vascular changes are accompanied. Occasionally, IgM and/or C3 depositions are noted in the sclerotic areas. Electron microscopically, diffuse effacement of foot processes are seen in non-sclerotic area like minimal change disease. Podocyte injury patterns including vacuolar changes are frequently examined. Recently, Columbia group has suggested morphologic classification of FSGS and they demonstrated very good prognosis of tip lesion and poor prognosis of both collapsing and cellular types. However, the pathogenetic classification has been suggested by others; hyperfilteration, podocyte injury, genetic lesions etc. Further studies are necessary to understand and treat this disease.

Congestion Control with Multiple Time Scale under Self-Similar Traffic (자기유사성 트래픽 조건에서 다중 시간 간격을 이용한 혼잡제어)

  • Park, Dong-Suk;Ra, Sang-Dong
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.9 no.1
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    • pp.65-75
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    • 2005
  • Measurement of network traffic have shown that the self-similarity is a ubiquitous phenomenon spanning across diverse network environments. In previous work, we have explored the feasibility of exploiting the long-range correlation structure in a self-similar traffic for the congestion control. We have advanced the framework of the multiple time scale congestion control and showed its effectiveness at enhancing performance for the rate-based feedback control. Our contribution is threefold. First, we define a modular extension of the TCP-a function called with a simple interface-that applies to various flavours of the TCP-e.g., Tahoe, Reno, Vegas and show that it significantly improves performance. Second, we show that a multiple time scale TCP endows the underlying feedback control with proactivity by bridging the uncertainty gap associated with reactive controls which is exacerbated by the high delay-bandwidth product in broadband wide area networks. Third, we investigate the influence of the three traffic control dimensions-tracking ability, connection duration, and fairness-on performance.

A BPN model for Web-based Business Process Reengineering and Specification (웹 기반 비즈니스 프로세스의 리엔지니어링과 명세를 위한 BPN 모형)

  • Jang, Soo-Jin;Choi, Sang-Soo;Lee, Gang-Soo
    • The KIPS Transactions:PartD
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    • v.10D no.3
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    • pp.471-488
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    • 2003
  • A web-based information system, that is a dominant type of information systems, suffers from the “web crisis” in development and maintenance of the system. To cope with the problem, a technology of reengineering to web-based business process, which is one of web engineering, is strongly needed. In this paper, we propose a BPN(Business Process Net) model and reengineering guides along with an application example, which are used for modeling web-based business processes and migrating to web-based information system. BPN model is a type of not only a Beta-distributed stochastics Petri net, but also an executable Activity diagram. BPN is modeled by using the Use Case analysis method and the Beta-distribution. The later is used for the purpose of modeling the uncertainty of execution time and cost of a business process. BPN model and reengineering heuristics might be used as a formal common model for business process specification languages, and analysis and design method for Web-based Information system, respectively.

A study on monitoring the subsidence of the gas utilities using GPS techniques (GPS를 이용한 가스설비 침하 감시 기술 연구)

  • Cho S.H.;Jeon K.S.;Park P.H.;Park J.U.;Joh J.H.
    • Journal of the Korean Institute of Gas
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    • v.3 no.2 s.7
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    • pp.53-61
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    • 1999
  • The safety of gas utilities is intimidated by many causes. Among them, subsidence is a dominant cause to decrease the safety of gas utilities. So it is very important to monitor the displacement of subsidence. The purpose of this study is to on-line monitor the subsidence of gas utilities using Static GPS(Global Positioning System)technique. Static GPS technique, which is one of various GPS techniques and originally applied to monitor the crustal activity, was applied for two gas station in Korea Gas Corporation. Prior to applying this technique to the field, i.e, gas station, a preliminary test was peformed to confirm the accuracy of this technique. As a result, it was proved that this technique can measure the displacement of gas utilities three dimensionally by sub-millimeter. After getting confirmation of GPS technique, we applied this technique for two gas stations and monitored the amount of subsidence during 5 months. As a result of field test, we can conclude that the gas stations was subsiding several millimeters in a year.

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The Semiotics Approach Method for Developing the Global Product Design (글로벌 제품디자인 개발을 위한 기호론적 접근방법)

  • 신홍재;함재룡
    • Archives of design research
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    • v.20
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    • pp.173-182
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    • 1997
  • In this era of global market without national boundaries, the prominent enterprises in Korea which recognized that our parted away from has confornted with endless competition have parted away from the domestic market and have aimed for internalization by declaring "Global management" and trying superior product-design development. This phenomenon is a reflection of the recognition by enterprises of the importance in global product design to increase market share. Accordingly, the purpose of this research is to present a method with respect to the design by revaluation and to approach the product design development by analogizing and accommodation the common preferences of humankind(the "preference theory")In relation to the constieuent elements such as design and communication, the approach of global product-design is to systemize the unfolding process for the concepts and ideas as expressed under the preference theory. In order to achieve this, a design approach based on the documentary research of the preference theory was applied step by step to the design methods. Further, the approach in relation to user and design, the ideology of enterprises and communication as expressed under the preference theory were presented Lastly, in the course of our approach in extraction the transformative ideas of our traditional culture, design for containers of cosmetics were used as an example.re used as an example.

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Minimum Weight Design of Built-up T Based on HCSR (HCSR 기반 T형 조립부재의 최소중량설계)

  • Shin, Sang-Hoon;Ko, Dae-Eun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.6
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    • pp.389-394
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    • 2017
  • In a conventional ship structure, stiffeners with an asymmetric section, such as inverted angles, are used widely despite the disadvantage of strength compared to the stiffeners with a symmetric section, such as a built-up T. On the other hand, T-type built-up members are attracting more attention than L-type inverted angles due to the increased size of ships. The purpose of this study was to develop an optimal design program for a built-up T, and apply an evolution strategy as an optimization technique. In the optimization process, the gross thickness concept was adopted for the design variables and objective function, and the constraints are set up based on HCSR (Harmonized Common Structural Rules). Using the developed program in this study, the optimal stiffener design was carried out for 300K VLCC and 158K COT of which the orders were obtained lately. The optimal results revealed the weight reduction effect of 144 tons and 60 tons, respectively.

Japanese and Chinese Journalists' Views on Anti-Korean Wave (일본과 중국 언론인들의 반한류 인식)

  • Kim, Eunjune;Kim, Sujeong
    • The Journal of the Korea Contents Association
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    • v.16 no.6
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    • pp.802-813
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    • 2016
  • This study examined the Japanese and Chinese journalist's views on anti-Korean wave, who are the public and authoritative discourse producers in Japan and China, respectively. In so doing, the study aims to understand the ways in which the phenomena of anti-Korean wave take place and are diffused. According to the findings, anti-Korean wave in north-east Asia is affected by anti-Korea sentiments that have been induced from historical and political relations as well as cultural conflicts. In specific, the anti-Korea sentiments found in both Japan and China are geopolitical particularity and historical relations function to frame their cultural receptions of Korean pop culture. In other words, the phenomena of anti-Korean wave in both countries do not stem directly from local audiences' either discontents or apathy on Korean pop contents. However, while Japanese anti-Korean wave seems to be mere expressions of anti-Korea sentiments, Chinese sentiments of anti-Korean wave are triggered and transferred by, or articulated with their anti-Korea sentiments.

A Comparative Analysis of Foreign Higher Education Recognition Systems in Australia and New Zealand (호주와 뉴질랜드의 해외학위인정제도 비교분석)

  • Chae, Jae-Eun
    • The Journal of the Korea Contents Association
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    • v.20 no.5
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    • pp.318-326
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    • 2020
  • The number of foreign qualification holders has been on the rise due to the globalization and the development of transportation. As in other developed nations, Korea faces the growing demand for foreign higher education recognition (FHER) since the number of foreign students and migrant workers has reached about one million recently. Unfortunately, there has been no FHER system in Korea so far. In this context, this study has compared the cases of Australia and New Zealand. The results reveal that these two countries are similar in that both of them have developed their own FHER system in order to attract highly qualified foreign workers and students. However, they are different in terms of the implementation of the FHER system and the development of the FHER database. Besides, the cases of both countries shed light on the key issues related to the FHER. Taken together, they provide significant implications for the Korean government which has to develop its own FHER system in the near future.

A Comparative Study on the Characteristics of Scholarly Communication in Subject Fields through the Web and Scientific Journals (웹과 학술지를 통한 학술커뮤니케이션의 특성연구)

  • Min, Ki-Eun;Chung, Young-Mee
    • Journal of the Korean Society for information Management
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    • v.24 no.4
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    • pp.73-96
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    • 2007
  • In this study, the characteristics of scholarly communication through the Web and scientific journals are explored, and scholarly communication patterns in two scientific disciplines are compared to reveal the difference. Economics and Computer Science-Information Systems are selected as two disciplines to be analyzed. In the data collection process, 10 keywords are extracted from a database for each subject field, and scholarly Web pages and journal articles related to these keywords are collected and analyzed. Our investigation includes the characteristics of scholarly Web pages, Multi-Dimensional Scaling (MDS) analysis of co-linked Web pages as well as co-cited journal articles, and changes in the scholarly communication activities occurring on the Web and in scientific journals respectively over time. We found certain differences as well as common features in scholarly communication patterns between the Web and scientific journals for both fields of Economics and Computer Science. We also found that scholarly communication occurring on the Web displays unique features for each subtopic within the same field of study.