• Title/Summary/Keyword: 리드

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A Study on Librarians' Perception about the Changing Role of University Libraries (대학도서관의 역할변화에 관한 사서의 인식조사 연구)

  • Noh, Younghee
    • Journal of the Korean Society for information Management
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    • v.33 no.2
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    • pp.227-256
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    • 2016
  • This study was carried out for the university library to find out a strategy to stand tall as an institution to lead the university, by reflecting the university environment having with drastic environmental changes and reflecting the evolution of information technology. As a result, first, university librarians responded that big issues related to the university library is the University Library Promotion Act, University Library evaluation and assessment indicators, the value of university libraries at the university, and changing spatial composition and functions of the university library. Second, university librarians responded that changes of the university environment, government policy on universities, various national projects, and various university reform policy significantly affect to the university library. Third, about what you think would be helpful to the crisis in their universities as changing role of the library, they responded that they can contribute in terms of improving students' information and technology literacy, improving students' reading skills, improving research capacity, and improve students' learning ability. Fourth, they responded that services that users demand the highest in the university library will be expansion of e-books and information resource.

An Improved High-Performance Protocol for Security Vulnerability of GSM based on SIM Card (SIM 카드 기반 보안 취약성을 개선한 고성능 GSM 보안 프로토콜)

  • Kim, Hee-Jung;Jeon, Ha-Yong;Lee, Ju-Hwa;Jung, Min-Soo
    • Journal of Korea Multimedia Society
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    • v.10 no.7
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    • pp.902-911
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    • 2007
  • GSM platform is a hugely successful wireless technology and an unprecedented story of global achievement. In less than ten years since the first GSM network was commercially launched, it became the world's leading and fastest growing mobile standard, using over 1 billion GSM subscribers across more than 200 countries of the world. GSM platform evolved into 3th generation mobile communication which includes not only voice call services but also the international roaming and various kinds of the multimedia services. GSM is an essential element techniques a safe data transmission and a personal private protection while support services. However, a crypto algorithm and a secure protocol for a safe data communication using GSM are indicating various kinds of problems. In this paper, we propose a more safer and more efficient authentication protocol in 3th generation network through analysis of GSM security mechanism of 2th/2.5th generation. This security protocol offers enforced security efficiency by using user verification between SIM/ME and reduction of authentication and key agreement step between SIM/ME/AuC.

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Telemetry System Encryption Technique using ARIA Encryption Algorithm (ARIA 암호 알고리즘을 이용한 원격측정 시스템 암호화 기법)

  • Choi, Seok-Hun;Lee, Nam-Sik;Kim, Bok-Ki
    • Journal of Advanced Navigation Technology
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    • v.24 no.2
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    • pp.134-141
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    • 2020
  • Telemetry system is a communication system that measures and transmits various signals in the aircraft to the ground for collecting and monitoring flight data during the development of unmanned air vehicle and satellite launch vehicles. With the recent development of wireless communication technology, it is becoming important to apply encryption of telemetry system to prepare with security threats that may occur during flight data transmission. In this paper, we suggested and implemented the application method of ARIA-256, Korean standard encryption algorithm, to apply encryption to telemetry system. In consideration of the block error propagation and the telemetry frame characteristics, frame is encrypted using the CTR mode and can apply the Reed-solomon codes recommended by CCSDS. ARIA algorithm and cipher frame are implemented in FPGA, and simulation and hardware verification system confirmed continuous frames encryption.

Characteristics of Nifedipine Loaded PLGA Wafer (니페디핀을 함유한 생분해성 PLGA 웨이퍼의 제조와 특성분석)

  • 서선아;최학수;이동헌;강길선;이해방
    • Polymer(Korea)
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    • v.25 no.6
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    • pp.884-892
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    • 2001
  • Biodegradable wafers were prepared with poly (L-lactide-co-glycolide) (50 : 50 mole ratio of lactide to glycolide, molecular weight:5000 g/mole) by direct compression method for the sustained release of nifedipine to investigate the possibility of the treatment of hypertension. PLGA wafers were prepared by altering initial drug/polymer loading ratio, wafer thickness, and hydroxypropyl methylcellulose (HPMC) content. These wafers showed new zero-order release patterns for 11 days, and various biphasic release patterns could be obtained by altering the composition of wafers such as addition of matrix binder as HPMC to the PLGA wafer to reduce release rate of initial phase. The onset of polymer mass loss only occured after 4 days and about 40% of mass loss was observed after 11 days nifedipine release. This system had advantages in terms of simplicity in design and obviousness of drug release rate and may be useful as an implantable dosage form.

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Characteristics of fiber-optic current sensors using perpendicular coil formers (수직원형틀을 이용한 광섬유전류센서의 동작특성)

  • 이명래;이용희;김만식
    • Korean Journal of Optics and Photonics
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    • v.7 no.4
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    • pp.419-427
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    • 1996
  • Thermally-stabilized fiber-optic current sensors are proposed and demonstrated. The sensor head is made of two coil formers combined perpendicularly. In this sensor head, bending-induced birefringences can be reduced to the level much smaller than those of the single former type because the eigen-axes of the two perpendicular coil formers are made orthogonal to each other. Moreover, thermal variation of the birefringence is also expected to be minimized by the orthogonality of the two polarization eigen-axes. We changed the temperature slowly in the range of 20~45$^{\circ}C$ during 100 minutes. The overall linearity of the sensor is better than 1.2% in the range of 0~1000A. The long-term fluctuation of the sensor is less than 1% when measured for 3 hours at 500A and room temperature. Two orthogonally-polarized laser diodes are combined together to make the incident beam unpolarized. In the signal processing, the signals are separated by two parts and normalized respectively, which minimize the efects of optical fluctuations coming from sources, connectors, etc.

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A Case Study on Pillow Talk(1959) and Down with Love(2003): Split Screen in Romantic Comedy Films (<필로우 톡>(1959)과 <다운 위드 러브>(2003): 로맨틱 코미디 영화의 화면 분할)

  • Chang, Woo-Jin
    • The Journal of the Korea Contents Association
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    • v.14 no.3
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    • pp.80-93
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    • 2014
  • This paper examines how split-screen technique works to meet the goals and strategies of the narrative in the romantic comedy films which deal with love and sex. The plot of romantic comedy films aims to the union and marriage of the couple, but is structured to delay the union as much as possible through comical situations and episodes. Usually split-screen scenes are placed before plot point 2 and serve to make a laugh and humor. Besides, it helps focusing on two main characters. Comedy related to love and sex comes from information gap between two main characters which can cause a tension, double meaning of spoken words and combination of split-screen images. Michael Gordon's Pillow Talk(1959) and Peyton Reed's Down with Love(2003) are reviewed in this study.

Non-explosive separation device using screw jack mechanism (나사잭 메커니즘을 이용한 비폭발식 분리장치)

  • Park, Hyun-Jun;Lee, Min-Su;Jo, Jae-Wook;Kim, Byung-Kyu
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.38 no.4
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    • pp.321-326
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    • 2010
  • The non-explosive release device using jack mechanism is designed and fabricated for the small satellite. As a triggering actuator for the release device, a piezo rotory motor with torque of more than $1.7kgf{\cdot}cm$ is employed to guarantee stable activation. For performance tests of separation device, we conducted release time test, preload test and shock test. The device was operated within 1.172sec and activated stably under load of 45kgf. Maximum shock was measured as 18G that is much less than the pyro-separation device produces. We confirmed the possibility as a satellite separation device through above presented tests.

Analytics Study on safety and stability of 50m class Portable Prestressing Bed (50m급 이동식 긴장대의 안전성 및 안정성에 관한 해석적 연구)

  • Kim, Jong Suk;Yoon, Ki Yong;Kim, Yong Hyeog
    • 한국방재학회:학술대회논문집
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    • 2011.02a
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    • pp.182-182
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    • 2011
  • 현재 국내에서 PSC 거더의 제작은 주로 포스트텐션방식을 사용하고 있다. 포스트텐션방식은 콘크리트 양생 후 긴장력을 도입하여 제작회전율이 높은 특성을 가지나 쉬스, 그라우팅, 정착장치 등이 요구되어 조립과정이 복잡하고 제작단가가 높다. 교량에 적용되는 PSC 거더를 포스트텐션방식 대신에 프리텐션방식으로 제작한다면 제작단가를 대폭 감소시킬 수 있을 것이나, 교량용 PSC 거더의 길이가 일반적으로 30~50m이므로 공장에서 제작하여 현장으로 운반하는 것은 운반비용의 상승 및 운반 가능한 크기의 제한을 받게 된다. 운반의 문제를 해결하기 위해서는 현장에서 PSC 거더를 제작하여야 하는데 현장에 긴장대를 고정식으로 설치하는 것은 제작단가의 상승으로 이어져 경제성을 잃게 된다. 따라서 현장에서 사용할 수 있도록 이동식 긴장대를 제작한다면 경제성을 갖춘 프리텐션방식의 PSC 거더 생산이 가능할 것이다. 50m급 이동식 긴장대에는 약 10MN에 이르는 매우 큰 긴장력이 가해져 이동식 긴장대가 콘크리트 양생전까지 이 긴장력을 저항하여야 한다. 본 논문에서는 유한요소 해석프로그램인 ABAQUS를 사용하여 50m급 PSC 거더를 생산할 수 있는 이동식 긴장대를 모델링하여 약 10MN에 이르는 긴장력이 가해질 때에 이동식 긴장대의 각 구성요소의 거동특성 및 하중에 대한 안전성 및 좌굴에 대한 안정성 확보 여부를 해석적으로 파악하고자 한다. 이동식 긴장대는 구성요소인 정착블럭(긴장BOX)과 중간연결블럭으로 나누어 모델링하였다. 정착블럭(긴장BOX)은 다수의 강판을 4절점 쉘요소(S4R)를 사용하여 직육면체의 BOX 형상에 내부를 보강한 단면으로 구성하였고, 중간연결블럭은 H형강 2개를 일체화한 긴장대 거더와 콘크리트 바닥판 블록이 볼트로 합성된 구조이며, H형강은 4절점 쉘요소(S4R), 바닥판블럭은 8절점솔리드요소(C3D8R)를 사용하였다. 긴장대거더와 바닥판블럭은 합성거동을 하도록 weld option을 사용하여 부분적으로 결합하였다. 정적해석결과 이동식 긴장대에 발생하는 응력은 도로교 설계기준에 SS400 강재의 허용응력 140MPa 보다 작으며 선형탄성좌굴 해석결과 가력하중의 2.22배 약 21MN의 하중이 가력되어야 전체좌굴이 발생하게 될 것으로 추정된다. 해석결과를 보아 50m급 PSC 거더를 생산할 수 있는 이동식 긴장대는 하중에 대한 안전성 및 좌굴에 대한 안정성을 확보하고 있는 것으로 판단된다.

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Development of Case-based Service Improvement Methodology By Utilizing TRIZ Concept (TRIZ를 활용한 사례 기반 서비스 개선 방법론 개발)

  • Hong, Jung-Wan;Choi, Jae Ho;Chun, Young Ho
    • The Journal of Society for e-Business Studies
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    • v.18 no.4
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    • pp.107-127
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    • 2013
  • In the 21st century, The service industry is becoming a new core business. In the modern industrial society, it escapes from supporting the manufacturing industry and finally leads to the growth of the manufacturing industry. Although many companies have met a variety of customer requirements through the existing service process, an organization or service developer has been failed because they had depended on intuitive judgment. Therefore, in this paper, we suggests CSIM(Case-based Service Improvement Methodology) to support improvement direction. This methodology is based on 120 cases and developed by utilizing the TRIZ concepts. As a result, CSIM will be a creative tool to support a developer to solve the problems.

Synthesis and Antimicrobial Activity of Phenazine Derivatives (Ⅱ) (페나진 유도체의 합성과 항균성에 관한 연구 (제 2 보))

  • Gang, Il Yeong;Kim, Sang Yeol;Kim, Ho Sik;Kim, Jong Dae;Heo, Geun
    • Journal of the Korean Chemical Society
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    • v.34 no.2
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    • pp.189-196
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    • 1990
  • 8-Acyl-2-hydroxyphenazine-5,10-dioxides and 8-acyl-2-aminophenazine-5,10-dioxides were synthesized by the reaction of hydroquinone and 4-aminophenol with 6-acylbenzofuroxans which had been obtained from acetanilide and n-acyl chlorides bearing butanoyl, hexanoyl and octanoyl groups. The antimicrobial activities of these phenazine dioxide derivatives were investigated in terms of minimum inhibitory concentration by the common twofold dilution technique. It was observed that the antimicrobial activity of the phenazine dioxide derivatives bearing octanoyl group was stronger than that of those bearing butanoyl and hexanoyl groups in gram positive microorgamisms, but it was observed that the antimicrobial activity and the number of the carbon atom of acyl groups did not have any relation in gram negative microorganisms. When the activity of xanthine oxidase which is the key enzyme in the generation of superoxide anion radical ($O_2^-$), was measured in the presence of phenazine dioxide derivatives, the inhibitory action of the enzyme activity of 8-acyl-2-hydroxyphenazine-5,10-dioxides was increased in accordance with the number of the carbon atom of acyl groups.

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