• Title/Summary/Keyword: transmission power

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The Strategies of Logistics Management for SMEs through CALS/EC (중소기업 물류경영 정보화를 위한 CALS/EC 전략)

  • Kim, Chang-Gyun
    • International Commerce and Information Review
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    • v.1 no.1
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    • pp.179-201
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    • 1999
  • CALS/EC is about doing business electronically. It is based on the electronic processing and transmission of data, including text, sound and video. It encompasses many diverse activities including electronic trading of goods and services, online delivery of digital content, electronic fund transfers, electronic share trading, electronic bills of lading, commercial auctions, collaborative design and engineering, online sourcing, public procuremet, direct consumer marketing, and after-sales service. It involves both products(e.g. consumer goods, specialised medical equipment) and services(e.g. information services, financial and legal services); traditional activities(e.g. healthcare, education) and new activities (e.g. virtual malls). CALS/EC will be emerging to replace and substitute the role of the conventional market. By changing and eliminating some processes of the transactions, the electronic market and the electronic commerce will redistribute the power and hence the benefits of the market activities. Traditional way of doing business may enter into the new electronic market because the role and function of trust and established reputation will be reinforced in the electronic market. The CALS/EC through the Internet has been in the spotlight in the shopping behavior of the consumers. Accordingly Corporates are trying to adapt themselves to those rapidly changing environments being affected by the Internet. Among others, particularly to be noted is the CALS/EC between corporations and consumers whose potential growth can be considered very substantial. This report, focusing on the introduction of CALS/EC for the logistics of SMEs, will allow us to prepare more efficiently for the coming 21st Century. It is obvious that CALS/EC is fast becoming the useful way of exchanging not only information but products in business between firm-to-firm and firm-to-customer.

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A Study On The Design of Patient Monitoring System Using RFID/WSN Based on Complex Event Processing (복합 이벤트 처리기반 RFID/WSN을 이용한 환자모니터링 시스템 설계에 관한 연구)

  • Park, Yong-Min;Oh, Young-Hwan
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.46 no.10
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    • pp.1-7
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    • 2009
  • Nowadays there are many studies and there's huge development about RFID and WSN which have great developmental potential to many kinds of applications. In particular, the healthcare field is expected to could be securing international competitive power in u-Healthcare and combined medical treatment industry and service. More and more real time application apply RFID and WSN technology to identify, data collect and locate objects. Wide deployment of RFID and WSN will generate an unprecedented volume of primitive data in a short time. Duplication and redundancy of primitive data will affect real time performance of application. Thus, emerging applications must filter primitive data and correlate them for complex pattern detection and transform them to events that provide meaningful, actionable information to end application. In this paper, we design a complex event processing system. This system will process RFID and WSN primitive data and event and perform data transformation. Integrate RFID and WSN system had applied each now in medical treatment through this study and efficient data transmission and management forecast that is possible.

A Study on Electrooptic $Ti:LiNbO_3$ Mach-Zehnder integrated-optic interferometers for Electric-Field Measurement (전계측정용 전기광학 $Ti:LiNbO_3$ Mach-Zehnder 집적광학 간섭기에 관한 연구)

  • Jung, Hong-Sik
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.48 no.12
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    • pp.15-22
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    • 2011
  • Integrated-optic symmetric/asymmetric Mach-Zehnder interferometers at $1.3{\mu}m$ wavelength were studied as sensing part for electric-field measurement system. The devices were simulated based on the BPM software and fabricated utilizing Ti-diffused $LiNbO_3$ channel optical waveguides and lumped-type electrodes. A half-wave voltage of $V_{\pi}$=6.6V and modulation depth of 100% and 75% for a symmetric structure were measured for 200Hz and 1kHz electrical signal bandwidth, respectively. By the way, almost half-maximum power transmission was observed for asymmetric interferometers with ${\pi}$/2 intrinsic phase difference. Expected experimental measurements were observed for 1kHz electrical signal bandwidth.

Implementation of Multi-layer PCB Design Simulator for Controlled Impedance (제어된 임피던스용 다층 PCB 설계 시뮬레이터 구현)

  • Yoon, Dal-Hwan;Cho, Myun-Gyun;Lin, Chi-Ho
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.48 no.12
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    • pp.73-81
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    • 2011
  • As high speed digital systems continue to use components with faster edge rate and clock speeds, transmission of the digital information, it can bring about many troubles. The increasing requirement for controlled impedance PCBs becomes both a critical success factor and a design challenge to implement a system. Especially, the noise sources in high frequency digital systems include the noise in power supply, ground and packaging, and they destroy the fidelity of signals. Therefore PCB design with impendence matching is needed to improve fidelity of signal in H/W. In this paper, we have developed an impedance control and analysis tool for multi-layer PCB design, and simulates the tracks controlled impedance with the test coupon. So, it can save the design time and support the economical PCB design.

Kinetic Study of the Visible Light-Induced Sonophotocatalytic Degradation of MB Solution in the Presence of Fe/TiO2-MWCNT Catalyst

  • Zhang, Kan;Oh, Won-Chun
    • Bulletin of the Korean Chemical Society
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    • v.31 no.6
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    • pp.1589-1595
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    • 2010
  • In order to effective degradation of organic dye both under visible light or ultrasonic irradiation, the MWCNTs (multiwalled carbon nanotube) deposited with Fe and $TiO_2$ were prepared by a modified sol-gel method. The Fe/$TiO_2$-MWCNT catalyst was characterized by surface area of BET, scanning electron microscope (SEM), Transmission Electron Microscope (TEM), X-ray diffraction (XRD), and energy dispersive X-ray (EDX) and ultraviolet-visible (UV-vis) spectroscopy. The low intensity visible light and low power ultrasound was as an irradiation source and the methylene blue (MB) was choose as the model organic dye. Then degradation experiments were carried out in present of undoped $TiO_2$, Fe/$TiO_2$ and Fe/$TiO_2$-MWCNT catalysts. Through the degradation of MB solution, the results showed the feasible and potential use of Fe/$TiO_2$-MWCNT catalyst under visible light and ultrasonic irradiation due to the enhanced formation of reactive radicals as well as the possible visible light and the increase of ultrasound-induced active surface area of the catalyst. After addition of $H_2O_2$, the MB degradation rates have been accelerated, especially with Fe/$TiO_2$-MWCNT catalyst, in case of that the photo-Fenton reaction occurred. The sonophotocatalysis was always faster than the respective individual processes due to the more formation of reactive radicals as well as the increase of the active surface area of Fe/$TiO_2$-MWCNT catalyst.

A Study on Error Compensation for Quadrature Modulator in Frequency Direct Conversion Method (주파수 직접변환방식의 직교변조부 에러보정에 관한 연구)

  • 백주기;이일규;방성일;진년강
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.9 no.4
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    • pp.542-551
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    • 1998
  • In this study, a method of error compensation for channel gain imbalance, phase imbalance and local oscillator leakage in the modulator of frequency direct conversion is suggested. The compensation of channel imbalance can be carried out by using the received power after transmitting test signal. By applying this method, the phase imbalance conversion with frequency can be easily compensated since this method is rarely affected by the transmission channel. It is confirmed that the algorithm proposed in this study(iteration coefficient=11) converges faster than conventional algorithm(iteration coefficient=43). From the numerical results, the DC-offset, channel gain, phase imbalance compensation coefficient and iteration number converges into($f_1$=0.0199999, $f_2$=-0.050001, $C_{22}$=0.9133, $C_{12}$=-0.0524, N=13) when the local oscillator leakage is not considered. However, it converges into($f_1$=-0.02, $f_2$=-2.2476, $C_{22}$=0.9133, $C_{12}$=-0.0524, N=16) when the local oscillator leakage is considered.

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Design of the Beam Tilted Series-fed Microstrip Array Antenna (빔경사 직렬 급전형 마이크로스트립 배열 안테나 설계)

  • 이진선;정민길;김진생;이정남;강치운;이우수;이문수
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.8 no.1
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    • pp.35-41
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    • 1997
  • A series-fed microstrip array antenna of beamwidth $10^{\circ}$, squint angle $80^{\circ}$ and SLL -15 dB below is designed. Series-fed arrays are formed by interconnecting all the elements by high-impedance transmission lines and feeding the power at the first element and it is a traveling-wave antenna which is terminated with a matched load. Radiation patterns and impedance matching of the antenna are analyzed by Ensemble 4.0, which is a popular software package for designing printed antennas and arrays. The squint angle of beam can be controlled by the spacing between the elements. The major advantages of series-fed array antennas are that feed arangement is compact and the losses associated with the feeding network are less than those of a corporate feed type. The antennas are fabricated on the RT/Duroid Laminates of 62 mil thickness. The experimental results are very close to the specifications to be designed.

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Comparison Analysis of Time and Frequency Resource of Candidate Waveforms for 5G Mobile Communications (5세대 이동통신을 위한 후보 변조기술들의 시간과 주파수 자원 비교 분석)

  • An, Changyoung;Ryu, Heung-Gyoon
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.27 no.11
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    • pp.987-995
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    • 2016
  • One of evaluation indicators of candidate waveforms for 5G mobile communication is spectral efficiency improvement by OOB(Out of Band) power reduction technique. In this paper, time-frequency resource allocation characteristic of UFMC(Universal Filtered Multi-Carrier), FBMC(Filter Bank Multi-Carrier), and W-OFDM(Weighted Orthogonal Frequency Division Multiplexing) system is evaluated and analyzed. As simulation results, spectral efficiency characteristic of these systems have been improved according to time resource allocation. In this paper, we can confirm that each system has similar time-frequency efficiency characteristic when the number of transmission bit is same and four symbols are transmitted with the linear system condition. Also, we can conclude that FBMC system has the lowest time-frequency resource efficiency under the nonlinear condition.

A Study on Thermal Analytical Model for a Dry Dual Clutch (건식 듀얼 클러치의 열해석 모델에 대한 연구)

  • Liu, Hao;Lee, J.C.;Noh, Y.J.;Cho, J.H.;Lee, H.R.;Koh, J.E.;Kang, J.W.
    • Journal of Drive and Control
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    • v.12 no.1
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    • pp.1-8
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    • 2015
  • The stability of friction characteristics and thermal management for a dry type dual clutch transmission (DCT) are inferior to those of a wet clutch. Too high temperature resulting from frequent engagement of DCT speeds up degradation or serious wear of the pressure plate or burning of the clutch disk lining. Even though it is significantly important to estimate the temperature of a dry double clutch (DDC) in real-time, few meaningful study of the thermal model of DDC has been known yet. This study presented a thermal analytical model of lumped parameters for a DDC by analyzing its each component firstly. Then a series of experimental test was carried out on the test bench with a patented temperature telemetry system to validate the proposed thermal model. The thermal model, whose optimal parameter values were found by optimization algorithm, was also simulated on the experimental test conditions. The simulation results of DDC temperature show consistency with the experiment, which validates the proposed thermal model of DDC.

Fabrication and Characteristic of C-doped Base AlGaAs/GaAs HBT using Carbontetrachloride $CCI_4$ ($CCI_4$ 를 사용하여 베이스를 탄소도핑한 AlGaAs/GaAs HBT의 제작 및 특성)

  • 손정환;김동욱;홍성철;권영세
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.30A no.12
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    • pp.51-59
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    • 1993
  • A 4${\times}10^{19}cm^{3}$ carbon-doped base AlGaAs/GaAs HBY was grown using carbontetracholoride(CCl$_4$) by atmospheric pressure MOCVD. Abruptness of emitter-base junction was characterized by SIMS(secondary ion mass spectorscopy) and the doping concentration of base layer was confirmed by DXRD(double crystal X-ray diffractometry). Mesa-type HBTs were fabricated using wet etching and lift-off technique. The base sheet resistance of R$_{sheet}$=550${\Omega}$/square was measured using TLM(transmission line model) method. The fabricated transistor achieved a collector-base junction breakdown voltage of BV$_{CBO}$=25V and a critical collector current density of J$_{O}$=40kA/cm$^2$ at V$_{CE}$=2V. The 50$\times$100$\mu$$^2$ emitter transistor showed a common emitter DC current gain of h$_{FE}$=30 at a collector current density of JS1CT=5kA/cm$^2$ and a base current ideality factor of ηS1EBT=1.4. The high frequency characterization of 5$\times$50$\mu$m$^2$ emitter transistor was carried out by on-wafer S-parameter measurement at 0.1~18.1GHz. Current gain cutoff frequency of f$_{T}$=27GHz and maximum oscillation frequency of f$_{max}$=16GHz were obtained from the measured Sparameter and device parameters of small-signal lumped-element equivalent network were extracted using Libra software. The fabricated HBT was proved to be useful to high speed and power spplications.

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