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Durablity Test and Field Application of Marine Concrete (항만콘크리트의 내구실험과 현장적용)

  • 강희철;정원기;이규정;박우선
    • Proceedings of the Korea Concrete Institute Conference
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    • 2000.04a
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    • pp.676-681
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    • 2000
  • This paper covers durability and field application of marine concrete which have been enhanced the resistance against deterioration in seawater. Fly ash concrete is applied to make the concrete with good durability. It is well known fly ash in concrete has a good performance preventing fro a sulphate attack and a steel corrosion. Several durability tests were performed to find characteristics of marine concrete which is proposed in this paper comparing with normal concrete. Field application was executed to compare results with laboratory test and to give a reliability to engineers. The project was supported by Ministry of Marine Affairs and Fisheries for two years.

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Graphene growth from polymers

  • Seo, Hong-Kyu;Lee, Tae-Woo
    • Carbon letters
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    • v.14 no.3
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    • pp.145-151
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    • 2013
  • Graphene is a fascinating material with excellent electrical, optical, mechanical, and chemical properties. Remarkable progress has been made in the development of methods for synthesizing large-area, high-quality graphene. Recently, the chemical vapor deposition method has opened up the possibility of using graphene for electronic devices and other applications. This review covers simple and inexpensive methods to grow graphene using polymers as solid carbon sources; which do not require an additional process to transfer graphene from the growth substrate to the receiver substrate.

SOME REMARKS ON COTORSION ENVELOPES OF MODULES

  • Kim, Hae-Sik;Song, Yeong-Moo
    • Bulletin of the Korean Mathematical Society
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    • v.44 no.4
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    • pp.589-596
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    • 2007
  • In this paper we prove that the extension of pure injective module is pure injective if and only if the cotorsion envelope and the pure injective envelope of any R-module M are isomorphic over M. And we prove that if the product of pure injective envelopes of flat modules is a pure injective envelope and the product of flat covers is a flat cover, then the product of cotorsion envelopes is a cotorsion envelope.

TOPOLOGICAL COMPLEXITY OF SEMIGROUP ACTIONS

  • Yan, Xinhua;He, Lianfa
    • Journal of the Korean Mathematical Society
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    • v.45 no.1
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    • pp.221-228
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    • 2008
  • In this paper, we study the complexity of semigroup actions using complexity functions of open covers. The main results are as follows: (1) A dynamical system is equicontinuous if and only if any open cover has bounded complexity; (2) Weak-mixing implies scattering; (3) We get a criterion for the scattering property.

ASYMPTOTIC RUIN PROBABILITIES IN A GENERALIZED JUMP-DIFFUSION RISK MODEL WITH CONSTANT FORCE OF INTEREST

  • Gao, Qingwu;Bao, Di
    • Journal of the Korean Mathematical Society
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    • v.51 no.4
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    • pp.735-749
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    • 2014
  • This paper studies the asymptotic behavior of the finite-time ruin probability in a jump-diffusion risk model with constant force of interest, upper tail asymptotically independent claims and a general counting arrival process. Particularly, if the claim inter-arrival times follow a certain dependence structure, the obtained result also covers the case of the infinite-time ruin probability.

Transparent Conductor-embedding Si for High-performing Hetrojunction Photoelectric Devices

  • Kim, Joondong
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.444.2-444.2
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    • 2014
  • Transparent conductors (TCs) are typically applied as an ohmic contact layer for photoelectric devices. Recent researches have illuminated a unique rectifying-junction design between a transparent conductor and a semiconductor layer. This approach may lead a significant reduction of device-fabrication steps and cost. A high-performing heterojunction device is presented, which provided significant photoelectric responses. This covers the fabrication processes, rectifying-junction formations and device analyses.

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Performance Simulation of Part Load Operation for 2MWe Circulating Fluidized Bed Boiler (2MWe 순환유동상 보일러의 부분 부하 운전 성능 모사)

  • Kim, Taehyun;Choi, Sangmin;Hyun, Ju-soo
    • 한국연소학회:학술대회논문집
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    • 2012.04a
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    • pp.35-36
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    • 2012
  • Part load operation usually covers large periods of the total operation time on the economic ground and electricity demand in small-scale boilers. Performance analysis of part load behavior is very important for the purpose of boiler operation optimization. A simple thermal calculation approach is applied to predict performance of a pilot-scale circulating fluidized bed (CFB) boiler at part load operation. Verification has been carried out by comparing between calculation results an operation data of the boiler.

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Product stewardship - Progress or Promises

  • Scott, David
    • Proceedings of the Korea Society of Environmental Toocicology Conference
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    • 2003.10a
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    • pp.131-142
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    • 2003
  • It's about three in the morning in a little farming village near the thriving metropolis of Sao Paulo in Brazil. Miguel, a 14-year-old schoolboy is fast asleep. Miguel was worried when he climbed into bed and drew the covers up. He was concerned about his homework - not that he had not done it. But rather what he had discovered while doing it. His homework was to interview his father, a tomato farmer, about how he uses pesticides and what precautions he takes to use them safely.

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Development of Monitoring Robot with Quadruped Link Mechanism (4족 링크 구조의 감시용 로봇 시스템 개발)

  • 정기범;박병훈;전병준;김동환
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.46-46
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    • 2000
  • A quadruped monitoring robot is introduced. The robot has several features that poses arbitrary position thanks to a 4-wheel hive mechanism, transmits an image and command data via RF wireless communication, and moreover, the imaged date are transferred through a network communication. The robot plays a role in monitoring what is happening around the robot and covers wide range due to a moving camera operated by the 4-wheel mechanism. The robot system can be applied k versatile models based the distinguished techniques introduced in this paper

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Constraints and Type Hierarchies for Korean Serial Verb Constructions - An Analytic Study within the HPSG Framework -

  • Song, Sang-Houn
    • Proceedings of the Korean Society for Language and Information Conference
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    • 2007.11a
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    • pp.440-449
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    • 2007
  • This paper provides a fine-grained analysis of Korean serial verb constructions within the HPSG framework, and covers major descriptive characteristics of the phenomena. This paper discusses constraints on serial verb constructions in terms of four aspects; transitivity, argument structure, semantic properties, and complementizers. As a result, 17 constraints have been built, which support the type hierarchies for Korean serial verb constructions. This paper also presents a sample derivation on the basis of on the constraints and the type hierarchies.

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