• Title/Summary/Keyword: Focusing effect

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Climate Change and the Thermohaline Circulation of the Oceans (기후 변환와 해양 열염분 순환)

  • Park, Young-Gyu
    • Atmosphere
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    • v.15 no.1
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    • pp.69-74
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    • 2005
  • In this short article, oceanic processes that could have strong effect on the climate have been explained while focusing on the oceanic thermohaline circulation (THC). First, the structure of THC is explained using a simple scaling law. Then, the thermohaline catastrophe, which is believed to be a cause of a rapid climate changes observed in paleoclimate records, and interdecadal variations in THC are explained. The interactions between the oceans and $CO_2$ are also mentioned briefly.

Actively Addressable Carbon NanoTube Emitters for Field Emission Display

  • Song, Yoon-Ho;Hwang, Chi-Sun;Kim, Kwang-Bok
    • 한국정보디스플레이학회:학술대회논문집
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    • 2003.07a
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    • pp.194-197
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    • 2003
  • The actively addressable carbon nanotube (CNT) emitters have been studied for stable and low-voltage driving field emission display (FED). The a-Si TFT and screen-printed CNT emitters were successfully integrated to fabricate the diode type active-matrix cathode and FED panel. Also, we propose a new FED architecture based on the actively controlled triode CNT emitters showing the properties of ideal triode type cathode with electron beam focusing effect.

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Study on Education of Power Electronics Engineering in Undergraduate Course focusing Experiments and simulation (실험실습을 강화한 학부과정에서의 전력전자공학 교육에 관한 연구)

  • Ji Jun-Keun
    • Proceedings of the KIPE Conference
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    • 2002.07a
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    • pp.639-642
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    • 2002
  • In this paper the method which can intensify effect of education and experiment in the subject of power electronics Is Introduced. Besides theoretical lectures by textbook during 3 hours a week, students can out the simulation and experiment using PSIM, special simulation program for power electronics, and 'Power Electronics Training System', experimental equipments of Lab-Volt Ltd. for power electronics, and 'Data Acquisition & Management System' Thus students can have profound understandings and experiences about various practical situations.

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Effect of Annealing Conditions on Microstructures and Mechanical Properties of a 5083 Al Alloy deformed at Cryogenic Temperature (어닐링 조건이 극저온 압연 5083 Al Alloy의 미세조직 및 기계적성질에 미치는 영향)

  • 이영범;남원종
    • Transactions of Materials Processing
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    • v.13 no.5
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    • pp.449-454
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    • 2004
  • The annealing behavior of a 5083 Al alloy deformed at cryogenic temperature was investigated, focusing on the evolution of microstructures and mechanical properties. Especially, the effects of annealing temperature, $150~300^{\circ}C$, and time, 3∼60min., on microstructures and mechanical properties of the sheets received 85% reduction at cryogenic temperature were investigated. The optimization of the annealing conditions resulted in a mixture of equiaxed grains and elongated subgrains, exhibiting a good combination of uniform elongation and high strength.

Investigation of self-focusing effect using near field scanning optical microscope (근접장 주사광학현미경을 이용한 자체집광현상에 관한 연구)

  • 유장훈;임상엽;양재석;이현호;주홍렬;박승한;이범구
    • Proceedings of the Optical Society of Korea Conference
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    • 2003.07a
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    • pp.190-191
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    • 2003
  • 물질에 큰 전기장을 가하였을 때 그 물질의 전기 감수율이 선형이 아닌 비선형관계를 갖게 되는데, 이로 인하여 선형계에서는 볼 수 없는 여러 가지 특이한 현상들이 관측된다. 이러한 비선형적인 현상 중에서 자체집광현상은 Guassian세기 분포를 가지는 빛을 매질에 통과시켰을 때 시료가 얇은 렌즈처럼 작용하는 것으로 설명할 수 있다. 비선형 효과에 의하여 레이저빔이 본래의 특성과 달라질 수 있고 빔의 심각한 변형을 일어난다. (중략)

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A Study on Army SNS Crisis Communication Strategy of 5G Age - Focusing on the effect of message form on the perception of soldiers - (5G 시대 군(軍) SNS 위기커뮤니케이션 전략에 관한 연구 - 메시지 형태가 장병 인식에 미치는 영향을 중심으로 -)

  • Kim, Tae-woong;Lee, Dong-hee;Lee, Sang-eun
    • Proceedings of the Korea Contents Association Conference
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    • 2019.05a
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    • pp.41-42
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    • 2019
  • 본 논문은 5G시대와 전 장병이 일과 후 병영에서 스마트폰을 사용하게 됨에 따라, SNS를 활용한 효과적인 군 위기관리 커뮤니케이션 전략을 제시하기 위해 SNS 메시지의 형태가 장병들의 위기에 대한 인식과 메시지의 수용도, 군에 대한 태도에 어떠한 영향을 주는지 실험연구를 통해 실증적으로 분석 연구하였으며 실무적 함의를 제시했다.

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Effect of Intersection Angle of the Flow-focusing Type Droplet Generation Device Channel on Droplet Diameter by using Numerical Simulation Modeling (수치해석 모델링을 이용한 교차 흐름 미세유체 액적 생성 디바이스 채널 교차각이 액적 직경에 미치는 영향)

  • Kim, Shang-Jin;Kang, Hyung-Sub;Yang, Yeong-Seok;Kim, Gi-Beum
    • Journal of Biomedical Engineering Research
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    • v.36 no.3
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    • pp.61-68
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    • 2015
  • In this paper, we studied the effects of intersection angles of the flow-foucusing type droplet generation device inlet channel on droplet diameter using numerical simulation modeling. We modeled different intersection angles with a fixed continuous channel width, dispersed channels width, orifices width, and expansion channels width. Numerical simulations were performed using COMSOL Multiphysics$^{(R)}$ to solve the incompressible Navier-Stokes equations for a two-phase flow in various flow-focusing geometries. Modeling results showed that an increase of the intersection angle causes an increase in the modification of the dispersed flow rate ($v^{\prime}{_d}$), and the increase of the modification of the continuous flow rate ($v^{\prime}{_c}$) obstructs the dispersed phase fluid flow, thereby reducing the droplet diameter. However, the droplet diameter did not decrease, even when the intersection angle increased. The droplet diameter decreased when the intersection angle was less than $90^{\circ}$, increased at an intersection angle of $90^{\circ}$, and decreased when the intersection angle was more than $90^{\circ}$. Furthermore, when the intermediate energy deceased, there was a decrease in the droplet diameter when the intersection angle increased. Therefore, variations in the droplet diameter can be used to change the intersection angle and fluid flow rate.

Characteristics of IEF Patterns and SDS-PAGE Results of Korean EPO Biosimilars

  • Kang, Min-Jung;Shin, Sang-Mi;Yoo, Hey-Hyun;Kwon, Oh-Seung;Jin, Chang-Bae
    • Bulletin of the Korean Chemical Society
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    • v.31 no.9
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    • pp.2493-2496
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    • 2010
  • Erythropoietin (EPO) is mainly produced in kidney and stimulates erythropoiesis. The use of recombinant EPOs for doping is prohibited because of its performance enhancing effect. This study investigated whether biosimilar EPOs could be differentiated from endogenous one by iso-electro-focusing plus double blotting and SDS-PAGE for antidoping analysis. The established method was validated with positive control urine. The band patterns were reproducible and meet the criteria, which was made by world anti doping agency (WADA). Isoelectric focusing was conducted in pH range 2 to 6. Recormon (La Roche), Aropotin (Kunwha), Epokine (CJ Pharm Co.), Eporon (Dong-A), Espogen (LG Life Sciences), and Dynepo (Shire Pharmaceuticals) were detected in basic region. All biosimilars showed discriminative isoelectric profiles from endogenous EPO profiles, but they showed different band patterns with the reference one except Epokine (CJ Pharm Co.). Next, SDS-PAGE of biosimilar EPOs resulted in different molecular weight patterns which were distributed higher than endogenous EPO. Commercial immune assay kit as an immune affinity purification tool and immobilized antibody coated magnetic bead were tested for the purification and concentration of EPO from urinary matrix. The antibody-coated magnetic bead gave better purification yield. The IEF plus double blotting and SDS-PAGE with immunoaffinity purification method established can be used to discriminate biosimilar EPOs from endogenous EPO.

A New Smart Antenna Algorithm for Improving the Performance of CDMA Reverse Link (CDMA 역방향 링크의 성능 개선을 위한 스마트 안테나 수신기 알고리즘)

  • 안재민;안치준;임민중
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.40 no.4
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    • pp.45-53
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    • 2003
  • A new smart antenna receiver which incorporates the spatial fourier Transform and the maximal ratio combining(MRC) is proposed. By adapting the spatial fourier transform, the proposed method could separate the received signal into several spatial frequency components which correspond to the arrival angles of signal components, which means the beam focusing. By using the MRC, the proposed method could achieve the maximum signal to noise ratio for the signal of interest. The proposed algorithm is integrated to the CDMA reverse link receiver and simulations are performed to confirm the performance. As a result, the beam focusing effect is confirmed and the performance gain with the proposed algorithm is comparable to ordinary smart antenna receivers. The simulations are performed over the additive white gaussian noise (AWGN) environments and the results are obtained for the beam focusing capability according to the angle of arrival of a signal and the bit error performance improvement according to the number of combining branches in the MRC.

The Impact on the Cultural Contents Market of the Legal Issue in Korea - Focusing 'Open Market' & 'Shut-down' in Game Industry (문화콘텐츠시장에 미치는 제도화의 영향에 대한 고찰 -게임산업의 오픈마켓과 셧다운제를 중심으로)

  • Kim, Min-Kyu
    • Journal of Korea Game Society
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    • v.12 no.2
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    • pp.63-74
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    • 2012
  • Two legal issues of the game industry in Korea are intersted in theses days. Open market & Shut-down. This article is studying for the impacts and the meaning of the game market that the institutionalization of two legal issue produce a powerful effect on. Social environment & recognition bring up the subject. This article is focusing at social environment & recognition and the forecasting game market. With the coming of smart-phone, the mobile contents market is changed. The open market for game is the issue for this changing market and assists the activation of the mobile-market with rational and futuristic perspectives. Shut-down(prohibition of the access of the young people in midnight) is the issue for game addiction and aggravates the game market and the perception on game with the focusing of the happening. This article points out the importance of institutionalization in consequence of the opposite direction of the market effects.