• Title/Summary/Keyword: Kwak Jong-seok

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High Out-of-Plane Alignment of Liquid Crystalline Methacrylate Copolymer Bearing Photoreactive 4-Styrylpyridine Moiety

  • Kwak, Gi-Seop;Kong, Jong-Yun;Kim, Min-Woo;Hyun, Seok-Hee;Kim, Woo-Sik
    • Macromolecular Research
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    • v.17 no.4
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    • pp.271-275
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    • 2009
  • This paper describes the out-of-plane order of a liquid crystalline(LC) methacrylate copolymer(3) comprised of a methacrylate(1) with a 4-styrylpyridine moiety as the photo-cyclodimerizable group and a benzoate moiety as the mesogenic group in the side chain, and another methacrylate(2) with a 4-(4-methoxyphenyl)benzoate moiety as the mesogenic group. The composition of 1 and 2 units in 3 was estimated to have a molar ratio of 54.2:45.8 by $^{1}H$ NMR spectroscopy. The X-ray diffraction study revealed that the copolymer forms a partial bilayer smectic structure. The copolymer gave rise to a high out-of-plane order parameter of about 0.74 in a wide LC temperature range of $110{\sim}160^{\circ}C$ after linearly polarized, UV light irradiation and subsequent annealing. Moreover, the external reflection IR analysis indicated that excess UV-light irradiation makes the out-of-plane LC structure of the copolymer appear in a higher and wider temperature range.

A Study on the Remuneration Management System for Legal Deposit of Digital Products (디지털자료 납본 보상금관리시스템에 관한 연구)

  • Lee, Seok-Hyoung;Kim, Kwang-Young;You, Beom-Jong;Kwak, Seung-Jin
    • Journal of Korean Library and Information Science Society
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    • v.40 no.1
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    • pp.233-251
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    • 2009
  • The National Library of Korea recently proposed a draft of an Act on Legal Deposit and Use for the Online Digital Products and researches about deposit system and remuneration of the digital products are in progress. Based on the law of library and copyright, remuneration of deposit and use products is paid. A draft of a proposed law include information about the remuneration payment. For these reasons, the method for efficient remuneration management is required. In this paper, we propose effective remuneration management system which follows a draft of an Act on Legal Deposit and Use for the Online Digital Products.

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Analysis of Ash and Trace Metals in Korean Native Bee Honey

  • Kim, Seok-Chang;Lee, Jong-Tae;Park, Chae-Kyu;Shim, Sang-Kwon;Han, Sang-Bae;Kwak, Yi-Seong;Whang, Mi-Sun;Won, Jun-Yeon
    • Journal of Applied Biological Chemistry
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    • v.49 no.4
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    • pp.154-156
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    • 2006
  • Trace metals in honey have an influence on the taste of honey along with pollens. Western bee honeys, which are mostly collected from acacia, have less than 0.1% of ash. Savor of Korean native-bee honey is thought to be due to the difference of the contents of trace metals. Korean native-bee honeys collected from Jirisan District, which is the greatest producing area of native-bee honey in Korea, showed high contents of ash. Korean native-bee honeys from the districts other than Jirisan District also showed similar results($0.44{\sim}0.83%$ of ash) to those from Jirisan District. Potassium was found to be the principal factor of high content of ash with over 85% of trace metals in ash.

Performance of Space Time Block Coded-Spatial Multiplexing Systems in Limited Feedback Channel (제한된 귀환채널에서 시공간블록부호화를 적용한 다중화 시스템의 성능)

  • Hwang, Hyeon-Chyeol;Shin, Seung-Hoon;Lim, Jong-Kyoung;Kim, Seok-Ho;Kwak, Kyung-Sup
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.9A
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    • pp.772-780
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    • 2005
  • In this paper, an efficient pre-processing in space tine block coded-spatial multiplexing systems is presented. The pre-processing scheme is designed empirically with extending the diagonally weighted orthogonal space time-block coded diversity system to spatial multiplexing system. Simulation results show the proposed scheme outperforms both the precoder using the predefued codebooks and typical antenna selection scheme over moderate doppler frequency in limited feedback channel.

Report on the Cooperative Experimental Study Program

  • Kim, Hun-Chol;Yang, Seung-Il;Lee, Seung-Hee;Kim, Eun-Chan;Kang, Kuk-Jin;Lee, Young-Gill;Kim, Yoon-Ho;Lee, Kwi-Joo;Kwak, Young-Ki;Joa, Soon-Won;Kim, Hyo-Chul;Van, Suak-Ho;Kim, Wu-Joan;Song, Mu-Seok;Cho, Kyu-Jong;Hong, Sung-Wan;Sin, Yeong-Kiun
    • Bulletin of the Society of Naval Architects of Korea
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    • v.24 no.3
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    • pp.17-24
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    • 1987
  • The present paper describes the results of the cooperative experimental study organized by the Resistance Committee of the Korea Towing Tank Conference, which aims to improve model testing technique and accuracy and to self-evaluate their own capabilities. A Series 60, $C_b=0.60$ model was tested at the towing tanks of Korea Institute of Machinery & Metals, Hyundai Maritime Research Institute, Seoul National University, and Inha University. Results for total resistance, wave pattern analysis, wave pattern analysis, wave profile, trim & sinkage and wake measure ments are presented.

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Evaluation of the Vulnerability of Bridge Foundations to Scour (세굴로 인한 교량기초의 위험도 평가)

  • Kwak, Ki-Seok;Park, Jae-Hyun;Lee, Ju-Hyung;Chung, Moon-Kyung;Kim, Jong-Cheon
    • Proceedings of the Korean Geotechical Society Conference
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    • 2005.03a
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    • pp.713-718
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    • 2005
  • A methodology is developed to evaluate the vulnerability of bridge piers to scour and to help establish effective disaster measures, taking into account the locality and scour characteristics in Korea. Based on the bearing capacity of bridge foundation-ground integrating system changed by scour, this methodology is able to prioritize bridge foundations reflecting on the geotechnical factors as well as hydraulic ones. The bridge foundation vulnerability to scour is categorized into 7 groups considering the concise information of the bridge foundation-ground integrating system. A case study of implementing this method which includes the analysis of the scour depth and evaluation, and categorizing the scour vulnerability of bridge foundation is presented.

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Development of the Monitoring System for Ocean Fish Farm (해상 가두리 양식장 암모니아 모니터링 시스템 개발)

  • Oh, Jin-Seok;Jo, Kwan-Jun;Kwak, Jun-Ho;Jin, Sun-Ho;Lee, Jong-Ho
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2006.06a
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    • pp.273-274
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    • 2006
  • The sea is origin of all lift, and 90% of the all living organisms are in the sea. The biosynthesis is very different. Many organisms are kept on a lower or developed to another evolutionary level than on shore. Our society is increasing demand and need for marine food and this food has to product at onshore or offshore fish farming sites. Ocean fish farms have a special operation properties such as a good quality water, net cage, sheltered locations and feeding system. The farming site is controlled and monitored for fish welfare as ammonia($NH_3$), temperature, the speed of a running fluid. Specially, the fish farm is seriously influenced by ammonia. In this paper, $NH_3$ monitoring system for ocean fish farm is researched for the suitable fish farming sites, and test equipment is designed for achieving practical data. The equipment wit monitoring algorithm is expected to the useful system for ocean fish farm.

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Modeling of 3-stage Electromagnetic Induction Launcher

  • Kwak, Daehwan;Kim, Young Bae;Kim, Jong Soo;Cho, Chuhyun;Yang, Kyung-Seung;Kim, Seong-Ho;Lee, Byung-Ha;An, Sanghyuk;Lee, Young-Hyun;Yoon, Seok Han;Koo, In Su;Baik, Yong Gi;Jin, Yun Sik
    • Journal of Magnetics
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    • v.20 no.4
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    • pp.394-399
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    • 2015
  • Electromagnetic Induction Launchers (EIL) have been receiving great attention due to their advantages of non-contact between the coils and a projectile. This paper describes the modeling and design of 3-stage EIL to accelerate a copper projectile of 50 kg with 290 mm diameter. Our EIL consists of three independent driving coils and pulsed power modules to generate separate driving currents. To find efficient acceleration conditions, the appropriate shape of the driving coils and the position of the projectile have been calculated by using a finite element analysis (FEA) method. The results showed that the projectile can be accelerated more effectively as the gap between the coils is smaller; a final velocity of 45 m/s was obtained. The acceleration efficiency was estimated to be 23.4% when a total electrical energy of 216 kJ was discharged.

Glossodynia as an Unusual Manifestation of Vitamin B12 Deficiency -A case report- (혀통증으로 나타난 비타민 B12 결핍증 -증례보고-)

  • Lee, Jung Hun;Jeong, Il Man;Seo, Won Goo;Woo, Chul Ho;Bae, Jong Seok;Mun, Sung Ha;Kwak, In Suk;Kim, Kwang Min
    • The Korean Journal of Pain
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    • v.19 no.2
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    • pp.275-277
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    • 2006
  • A 58-year old male patient, with a history of gastrectomy, came to our department for recently aggravated glossodynia. A delicate physical examination revealed gait ataxia and a positive Rhomberg test. He was diagnosed as having vitamin B12 deficiency using a combination of the laboratory results, such as macrocytic anemia. It was thought that the tongue pain might have been a main clinical manifestation of vitamin B12 deficiency.

Economical assessment and selection of corrosion protections for marine steel piles (해상 강관말뚝 활용을 위한 방식기법 선정 및 경제성 검토)

  • Lee, Ju-Hyung;Lee, Jong-Ku;Park, Jae-Hyun;Kwak, Ki-Seok;Chung, Moon-Kyung
    • Proceedings of the Korean Geotechical Society Conference
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    • 2009.03a
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    • pp.551-560
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    • 2009
  • Introduced was a new anti-corrosive method with improved ease of construction, economy, and durability that could be applicable for steel-composite drilled shaft. The feasibility and economy of sea-water-resistant steel was evaluated under the assumption that it was to substitute carbon steel for steel casing of drilled shaft foundation as a load carrying structural member not just as a sacrifice casing, and that anti-corrosive protection measures as required by the domestic standards was applied. Sea-water-resistant steel was found to cost 30% to 55% more, depending on pile diameter and the type of applied anti-corrosive measures, than carbon steel for the service life time of 70 years: 50% to 90% more for 100 years of service life.

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