• Title/Summary/Keyword: Radio frequency

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Analysis for the Consumers' Cognition and Opinion about Corporate Social Responsibility(CSR) (기업의 사회공헌 활동에 대한 소비자 인식 분석)

  • Ahn, Joo-Ah;Hwang, Kyong-Ah;Yoon, Shuk-Nyun
    • Korean journal of communication and information
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    • v.56
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    • pp.237-256
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    • 2011
  • The goal of this study is to examine consumers' cognition for the corporate social responsibility(CSR) and opinion to practical use of CSR on advertising (ex. corporate PR) in situation that CSR is treated with long-term and continuous activity in strategic marketing. The results of survey in this study are, first, the best effective method of CSR to introduce is TV or radio program placed first, internet came second, and followed by advertising. But the cognition process of CSR is internet palaced first in frequency. Thus it is very important to use of new media as a internet with regard to CSR. Second, respondents have thought positively about CSR and to practical use of CSR on advertising. But respondents answered that CSR is not enough though it's importance. Therefore marketers of companies is needed to transfer direction of CSR accord with consumers' liking and taste. Third, consumers have recognized that CSR in connection with characteristics core business of the companies. It is, image of company is not detached with CSR, more effective that CSR reflected characteristics of the company. Fourth, consumers have thought to active for CSR that the companies they like. Finally, these results are showed that is important brand management and corporate image management in strategic and macroscopic level include CSR.

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The Study on The Ventilated Flow in The Railway Tunnel Mock-Up for Tunnel Fire-Driven Flow Experiment (철도터널 화재유동 실험을 위한 모형 터널에서의 환기 유동 형태에 관한 연구)

  • Jang, Yong-Jun;Kim, Seung-Tae;Kim, Dong-Hyeon;Park, Won-Hee
    • Proceedings of the KSR Conference
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    • 2008.06a
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    • pp.1781-1788
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    • 2008
  • This report is the result of a basic experiment done on a mock-up tunnel, of what happens to the ventilated flow and fire driven flow inside a railway tunnel as the current inside the tunnel changes when an anti-smoke or a radio frequency invert control is installed. The duct used in this experiment is 10m in length, 0.5m in height and 0.25m in width and made of acrylic. An anti-smoke system with a motor that can produce current of 10m/sec maximum in order to create ventilated flow, has been installed. A honeycomb has been installed at the entrance of the duct to create a current flow that exists in tunnels. In order to create a ventilated flow, a current of 4m/s, 6m/s and 8m/s were generated using the anti-smoke system, as the study of current developed. A Hot-wire(TSI) and Pressure sensor(ENDEVCO) was installed in the duct, 1m apart, as the measurement of current and pressure went on. The current and pressure were automatically measured through the Lap View program and PC; the current flow in the mock-up tunnel generated by the honeycomb has been analyzed the pressure distribution and pressure drop has been analyzed.

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The Optimization of RF Atmospheric Pressure Plasma Treatment Process for Improving the Surface Free Energy of Polymethylmethacrylate (PMMA) (Polymethylmethacrylate (PMMA) 표면개질을 위한 RF 대기압 플라즈마 처리공정의 최적화)

  • Nam, Ki-Chun;Myung, Sung-Woon;Choi, Ho-Suk
    • Journal of Adhesion and Interface
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    • v.6 no.3
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    • pp.1-9
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    • 2005
  • This study investigated the influence of atmospheric plasma factors such as RF power, treatment time, the gap distance between discharge and sample, and the gas flow rate of Ar on the surface property by using the design of experiment (DOE) method. The plasma treatment time (s), plasma power (W), gap distance (mm) between discharge and sample, and flow rate of Ar gas were in order of important factors for changing the surface free energy of PMMA plates. As a result, the most effective factor for improving the surface free energy of PMMA plates is the distance (mm) from discharge glow to sample plate. Because of the interaction between plasma power (W) and treatment time (s), the power dose (J) factor which multiply plasma power (W) by treatment time (s) should be significantly considered. The optimum condition for maximizing the surface free energy of PMMA plate was found at 1500J of power dose. Through XPS and AFM analysis, we also observed the change of chemical composition, surface morphology and roughness before and after plasma treatment. It is considered that the change of surface free energy of PMMA plate with plasma treatment is influenced by the introduction of polar functional group as well as the increase of surface roughness.

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Time-encoded Near-infrared (NIR) Spectroscopic Comparison of Absorbance Measurement Using an Acousto-optic NIR Swept Laser Source (음향광학 파장선택 필터 기반 파장훑음 레이저를 이용한 시간-인코딩 된 근적외선 흡광도 측정 비교 연구)

  • Jang, Hansol;Kim, Gyeong Hun;Han, Ga-Hee;Cho, Jaedu;Kim, Chang-Seok
    • Korean Journal of Optics and Photonics
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    • v.28 no.1
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    • pp.22-27
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    • 2017
  • Time-encoded near-infrared spectroscopy (NIRS) system is proposed, based on a near-infrared (NIR) swept laser source, for comparison to the conventional NIRS method using a detector-type spectrometer. The cavity of the NIR swept laser source consists of a semiconductor optical amplifier (SOA) with a gain region around 800 nm, and several fiber-optic components. To change the output wavelength in time using an applied electric radio-frequency signal, an acousto-optic tunable filter (AOTF) is introduced in the fiber ring cavity configuration. To demonstrate the feasibility of an NIR swept laser source for NIRS imaging, the spectroscopic comparison of two kinds of absorbance-measuring systems a detector-type spectrometer using a white light source, and a source-type spectrometer using an NIR swept laser is successfully performed with an NIR-absorbing dye.

Properties of TiN films prepared by using the DC sputtering and HIPIMS. (DC 스퍼터링과 HIPIMS로 제조한 TiN 박막의 특성 비교)

  • Byeon, In-Seop;Yang, Ji-Hun;Jeong, Jae-Hun;Kim, Seong-Hwan;Jeong, Jae-In
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2016.11a
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    • pp.102-102
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    • 2016
  • 본 연구에서는 직류 전원(direct current; DC)을 이용한 스퍼터링과 고전력펄스 마그네트론 스퍼터링(high-power impulse magentron sputtering; HIPIMS)의 두 가지 방법과 빗각 증착을 적용하여 제조한 티타늄 질화물(TiN) 박막의 미세구조 변화가 물성에 미치는 영향을 확인하였다. TiN 박막은 99.5%의 Ti 타겟을 사용하고, Ar가스와 $N_2$ 분위기에서 스테인리스(SUS304)와 초경(cdmented carbide; WC-10wt.%Co) 기판위에 코팅하였다. 기판은 알코올과 아세톤으로 초음파 세척을 실시한 후 진공용기에 장착하고 기본 진공도인 ${\sim}2.0{\times}10^{-5}Torr$ 까지 진공배기를 실시하였다. 기판과 타겟 간의 거리는 DC 스퍼터링은 10 cm, HIPIMS 스퍼터링은 8.5 cm 이었다. 진공용기의 압력이 기본 진공도까지 배기되면 Ar 가스를 ${\sim}10^{-2}Torr$로 주입한 후 기판에 라디오 주파수(radio frequency; RF) 전원으로 약 -800 V의 전압을 인가하여 글로우 방전을 발생시키고 약 30 분간 청정을 실시하였다. 기판의 청정이 끝난 후 기본 진공도까지 배기한 후 Ar와 $N_2$ 가스를 ${\sim}10^{-3}Torr$로 주입하여 TiN 코팅을 실시하였다. 빗각의 크기는 $45^{\circ}$$-45^{\circ}$이며, TiN 박막의 총 두께는 약 $2.5{\sim}4.0{\mu}m$ 로 유지하였다. 공정조건에 따라 TiN 박막의 주상정은 형태와 기울어진 각도가 다른 것을 확인하였다. DC 스퍼터링으로 제조된 TiN 박막은 기판홀더에 약 -100 V 의 bias 전압을 인가하면 인가하지 않은 박막에 비해 치밀한 박막의 성장과 경도 값도 증가하는 사실을 확인하였다. 또한 빗각을 적용하고 bias 전압을 인가하지 않은 시편에서 박리현상이 일어났다. HIPIMS로 제조한 TiN 박막은 bias 전압을 인가한 박막과 인가하지 않은 박막의 주상정 형상과 경도 값에 큰 차이가 없었으며, 박막의 박리현상은 모든 시편에서 일어나지 않았다. DC 스퍼터링으로 제조한 TiN 박막은 bias 전압을 인가하지 않으면 색상이 노란색이 아닌 갈색으로 나타났으며, HIPIMS으로 제조한 박막은 bias 전압 인가 유무에 상관없이 노란색 색상을 나타냈다. 앞서 설명한 DC 스퍼터링과 HIPIMS의 공정조건에 따라 나타난 박막의 경도, 색상, 물성변화 차이는 DC 스퍼터링보다 높은 HIPIMS의 이온화율에서 기인한 것으로 생각된다. 본 연구결과를 이용하면 다양한 형태의 박막 구조 제어가 가능하고 이러한 미세구조 제어를 통해서 박막의 물성도 제어가 가능할 것으로 판단된다.

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Applications of Regularized Dequantizers for Compressed Images (압축된 영상에서 정규화 된 역양자화기의 응용)

  • Lee, Gun-Ho;Sung, Ju-Seung;Song, Moon-Ho
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.39 no.5
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    • pp.11-20
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    • 2002
  • Based on regularization principles, we propose a new dequantization scheme on DCT-based transform coding for reducing of blocking artifacts and minimizing the quantization error. The conventional image dequantization is simply to multiply the received quantized DCT coefficients by the quantization matrix. Therefore, for each DCT coefficients, we premise that the quantization noise is as large as half quantizer step size (in DCT domain). Our approach is based on basic constraint that quantization error is bounded to ${\pm}$(quantizer spacing/2) and at least there are not high frequency components corresponding to discontinuities across block boundaries of the images. Through regularization, our proposed dequantization scheme, sharply reduces blocking artifacts in decoded images. Our proposed algorithm guarantees that the dequantization process will map the quantized DCT coefficients will be evaluated against the standard JPEG, MPEG-1 and H.263 (with Annex J deblocking filter) decoding process. The experimental results will show visual improvements as well as numerical improvements in terms of the peak-signal-to-noise ratio (PSNR) and the blockiness measure (BM) to be defined.

Enhanced Energy Harvester Based on Vibration Analysis of Bicycle Riding (자전거 주행의 진동 분석에 기반한 에너지 수확 증진 기술 개발)

  • Yeo, Jung-Jin;Ryu, Mun-Ho;Kim, Jung-Ja;Yang, Yoon-Seok
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.49 no.1
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    • pp.47-56
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    • 2012
  • Bicycle has a large amount of kinetic energy available for energy harvesting technology in its speedy and balanced riding movement. Systematic and realistic analysis of its dynamic property is essential to improve the efficiency of energy harvester. However, there has not been enough researches about precise measurement or analysis of bicycle dynamics on real roads. This study aims to investigate the characteristics of vibrational movement of bicycle using MEMS-based accelerometer and to develop a prototype of electromagnetic energy harvester with nonlinear behavior which is proper to the random vibrations accompanied in bicycle riding. The vibrational components have average magnitude of 1 g and turn out to be independent of riding speed. The developed prototype of energy harvester was installed on a front port of a bicycle to use this ambient vibration and generated an average electrical power of 1.5 mW which is enough to support power for most of portable sensors and short range radio-frequency communication. Further study about isolation of vibration from a rider and conversion efficiency is ongoing. The developed energy harvester is expected to be a platform technology for sustainable portable power supply for various smart IT devices and applications.

Effects of Working Pressure on Structural and Optical Properties of HfO2 Thin Films (공정 압력이 HfO2 박막의 구조적 및 광학적 특성에 미치는 영향)

  • Joung, Yang-Hee;Kang, Seong-Jun
    • The Journal of the Korea institute of electronic communication sciences
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    • v.12 no.6
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    • pp.1019-1026
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    • 2017
  • The structural properties of $HfO_2$ films could be improved by calibrating the working pressure owing to the enhanced quality of a thin film. We deposited $HfO_2$ films on glass substrates by radio frequency (RF) magnetron sputtering under a base vacuum pressure lower than $4.5{\times}10^{-6}Pa$, RF power of 100 W, substrate temperature of $300^{\circ}C$. The working pressures were varied from 1 mTorr to 15 mTorr. Subsequently, their structural and optical properties were investigated. In particular, the $HfO_2$ film deposited at 1 mTorr had superior properties than the others, with a crystallite size of 10.27 nm, surface roughness of 1.173 nm, refractive index of 2.0937 at 550 nm, and 84.85 % transmittance at 550 nm. These results indicate that the $HfO_2$ film deposited at 1 mTorr is suitable for application in transparent electric devices.

The characteristics of bismuth magnesium niobate multi layers deposited by sputtering at room temperature for appling to embedded capacitor (임베디드 커패시터로의 응용을 위해 상온에서 RF 스퍼터링법에 의한 증착된 bismuth magnesium niobate 다층 박막의 특성평가)

  • Ahn, Jun-Ku;Cho, Hyun-Jin;Ryu, Taek-Hee;Park, Kyung-Woo;Cuong, Nguyen Duy;Hur, Sung-Gi;Seong, Nak-Jin;Yoon, Soon-Gil
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.06a
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    • pp.62-62
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    • 2008
  • As micro-system move toward higher speed and miniaturization, requirements for embedding the passive components into printed circuit boards (PCBs) grow consistently. They should be fabricated in smaller size with maintaining and even improving the overall performance. Miniaturization potential steps from the replacement of surface-mount components and the subsequent reduction of the required wiring-board real estate. Among the embedded passive components, capacitors are most widely studied because they are the major components in terms of size and number. Embedding of passive components such as capacitors into polymer-based PCB is becoming an important strategy for electronics miniaturization, device reliability, and manufacturing cost reduction Now days, the dielectric films deposited directly on the polymer substrate are also studied widely. The processing temperature below $200^{\circ}C$ is required for polymer substrates. For a low temperature deposition, bismuth-based pyrochlore materials are known as promising candidate for capacitor $B_2Mg_{2/3}Nb_{4/3}O_7$ ($B_2MN$) multi layers were deposited on Pt/$TiO_2/SiO_2$/Si substrates by radio frequency magnetron sputtering system at room temperature. The physical and structural properties of them are investigated by SEM, AFM, TEM, XPS. The dielectric properties of MIM structured capacitors were evaluated by impedance analyzer (Agilent HP4194A). The leakage current characteristics of MIM structured capacitor were measured by semiconductor parameter analysis (Agilent HP4145B). 200 nm-thick $B_2MN$ muti layer were deposited at room temperature had capacitance density about $1{\mu}F/cm^2$ at 100kHz, dissipation factor of < 1% and dielectric constant of > 100 at 100kHz.

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The Clinical Review of Superior Vena Cava Syndrome (상대정맥 증후군의 임상적 고찰)

  • Kang, Joung-Sun;Lee, Sam-Beom;Lee, Choong-Ki;Chung, Jin-Hong;Lee, Hyoung-Woo;Lee, Kwan-Ho;Hyun, Myung-Soo;Lee, Hyun-Woo;Shin, Sei-One;Kim, Myung-Se
    • Journal of Yeungnam Medical Science
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    • v.7 no.2
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    • pp.151-158
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    • 1990
  • We reviewed 30 cases of superior vena cava syndrome in adult patients who were seen at the Yeungnam University Hospital from January 1985 to June 1990. The results were as follows : 1. The male-to-female ratio was 6.5:1, and the most patients were in the age group between the sixth and seventh decades. 2. The most common symptoms were dyspnea (87%) and followed by cough (63%), facial swelling (63%) and chest pain (44%) and the physical signs were dilated neck vein (97%), facial edema (93%) and facial flushing (45%) in order of frequency. 3. The simple chest x-ray findings were superior mediastinal widening (90%), right hilar mass (77%) and pleural effusion (31%). 4. Diagnosis was made by history and physical examination (100%), chest C-T scan (100%), simple chest x-ray (97%), bronchoscopy with biopsy (40%) and so on. 5. 21 cases of patients were confirmed by histology : 14 cases (46%) of bronchogenic ca. 4 cases (14%) of lymphoma, 3 cases (10%) of metastic lung ca. Of bronchogenic ca. small cell ca was 7 cases (23%), squamous cell ca, 5 cases (17%), and unclassified ca was 2 cases (6%). 6. In response of treatment, the clinical improvement was achieved in 18 cases with radiotherapy alone. 1 case with chemotherapy only, and 6 cases with radio-chemotherapy.

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