• Title/Summary/Keyword: multi-connection

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Multi-level PWM Inverter for 3-Phase High Voltage Power On-Grid (3상 고압 전력연계를 위한 다중레벨 인버터)

  • Ahn, Hyun-Jin;Lee, Hwa-Chun;Song, Sung-Gun;Lee, Sang-Hun;Park, Sung-Jun;Kim, Kwang-Heon;Lim, Young-Cheol
    • Proceedings of the KIPE Conference
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    • 2008.06a
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    • pp.562-564
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    • 2008
  • This paper deals with the three phase high voltage power-grid connection topology using multi-level inverter. Due to the multi-level inverter, these are improved effect of fluctuating voltage, problem of EMC and switching loss using suitable switching patterns of device, above all thing, it is easy to realize the system because of using lower voltage rating switch. This topology can be applicable to power-grid connection of wind system, there is a good point about economical efficiency. The simulation results are presented to verify the validity of the proposed topology.

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Single and multi-material topology optimization of CFRP composites to retrofit beam-column connection

  • Dang, Hoang V.;Lee, Dongkyu;Lee, Kihak
    • Computers and Concrete
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    • v.19 no.4
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    • pp.405-411
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    • 2017
  • Carbon Fiber Reinforced Plastic (CFRP) has commonly been used to strengthen existing RC structures. Wrapping the whole component with CFRP is an effective method and simple to execute. Besides, specific configuration of CFRP sheets (L, X and T shape) has also been considered in some experiments to examine CFRP effects in advance. This study aimed to provide an optimal CFRP configuration to effectively retrofit the beam-column connection using continuous material topology optimization procedure. In addition, Moved and Regularized Heaviside Functions and penalization factors were also considered. Furthermore, a multi-material procedure was also used to compare with the results from the single material procedure.

Japanese-Korean Machine Translation System Using Connection Forms of Neighboring Words (인접 단어들의 접속정보를 이용한 일한 기계번역 시스템)

  • Kim, Jung-In
    • Journal of Korea Multimedia Society
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    • v.7 no.7
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    • pp.998-1008
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    • 2004
  • There are many syntactic similarities between Japanese and Korean languages. Using these similarities, we can make out the Japanese-Korean translation system without most of syntactic analysis and semantic analysis. To improve the translation rates greatly, we have been developing the Japanese-Korean translation system using these similarities from several years ago. However, the system remains some problems such as a translation of inflected words, processing of multi-translatable words and so on. In this paper, we suggest the new method of Japanese-Korean translation by using relations of two neighboring words. To solve the problems, we investigated the connection rules of auxiliary verbs priority. And we design the translation table which is consists of entry tables and connection forms tables. A case of only one translation word, we can translate a Korean to Japanese by direct matching method use of only entry table, otherwise we have to evaluate the connection value by connection forms tables and then we can select the best translation word.

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Determination of the optimum connection length between modules in the design of microwave multistage amplifiers using amplifier modules (증폭모듈을 이용한 마이크로파 다단증폭기 설계시 최적의 모듈간 연결길이 결정)

  • 임종식;강성춘
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.34D no.3
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    • pp.25-33
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    • 1997
  • In the design of microwave multi-stage amplifiers composed of N amplifier modules, the variation of performances of amplifier as various connection length between modules has been studied. In addition, the methods, equations and conditions for the maximum gain or the most flat gain are presented. The results of sensitivity analysis for the connection length showed that the small change in phase of input, output reflection coefficients(S$_{11}$, S$_{22}$) of module itself is the most important in determination of connection length for the most flat gain. Th egain flatness of 2-module amplifier of which connection length between modules had been determined by presented methods was the best one out of performances with various arbitrary connectio lengths.s.

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A Development of CCTV Control System Based on Wireless Sensor Network (무선 센서 네트워크 기반 CCTV 제어 시스템 연구)

  • Cho, Soo-Hyung;Kim, Dae-Hwan
    • 한국정보통신설비학회:학술대회논문집
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    • 2009.08a
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    • pp.219-220
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    • 2009
  • Many surveillance cameras used in security system are controlled with RS-485 communication protocol. In this situation, if RS-485 connection can be replaced with wireless connection using sensor network technology, an installation will become ease because of no wired connection and also a deployment of cameras will become free. This paper explains about the design of wireless sensor node and the necessary implementation for an operation, which can be replacing RS-485 connection for the development of CCTV control system based on wireless sensor network. The hardware platform of sensor node was designed based on MicaZ and the software was developed based on TinyOS. To control surveillance cameras deployed on wide area, the supporting of multi-hop also was implemented. With the result of experiment deploying on real environment, it was revealed that the controller could control cameras quickly with wireless.

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A Study on the ATM Connection Admission Control using heterogeneous traffics (이질적인 트래픽을 이용한 ATM 연결수락제어에 관한 연구)

  • 전원구;이명호
    • Journal of the Korea Society of Computer and Information
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    • v.6 no.3
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    • pp.72-77
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    • 2001
  • The method of connection admission control is presented by using the equations related with traffic classes for real-time connection admission control. without assuming the cell arrival processes in the multi-level structure of ATM traffic control. The equations related with traffic classes are obtained by 3 or 4 of first order inequalities from the admissible ranges of connection considering the expected total instantaneous demand to guarantee the required quality of services of each class.

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A Study on Caching Management Technique in Mobile Ad-hoc Network (Mobile Ad-hoc Network에서 캐싱 관리 기법에 관한 연구)

  • Yang, Hwan Seok;Yoo, Seung Jae
    • Convergence Security Journal
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    • v.12 no.4
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    • pp.91-96
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    • 2012
  • MANET is developed technique fairly among many field of wireless network. Nodes which consist of MANET transmit data using multi-hop wireless connection. Caching scheme is technique which can improve data access capacity and availability of nodes. Previous studies were achieved about dynamic routing protocol to improve multi-hop connection of moving nodes. But management and maintenance of effective cache information because of movement of nodes is not easy. In this study, we proposed cluster-based caching scheme to manage connection by decreasing overhead and moving of nodes as moving node discovers cache of wish information. And HLP was used to maintain effective cache table in each cluster head. Efficiency of proposed technique in this study was confirmed by experiment.

On the Control of Energy Flow between the Connection Parts of Syllables for the Korean Multi-Syllabic Speech Synthesis in the Time Domain Using Mono-syllables as a Synthesis Unit (단음절 합성단위음을 사용한 시간영역에서의 한국어 다음절어 규칙합성을 위한 음절간 접속구간에서의 에너지 흐름 제어에 관한 연구)

  • 강찬희;김윤석
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.24 no.9B
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    • pp.1767-1774
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    • 1999
  • This paper is to synthesize Korean multi-syllabic speeches in the time domain using mono-syllables as a synthesis unit. Specially it is to control the shape forms of speech energy flows between the connection parts of syllables in the case of concatenation mono-syllables. For this it is controlled with the prosody parameters1) extracted from speech waveforms in the time domains and presented the experimental results controlled the energy flows by using the induced concatenation rules from the korean syllable shapeforms in connetion parts of syllables. In the results of experiments, it is removed the incontinuities of energy follows in the connection parts produced by concatenating the mono-syllables in the time domain and also improved the qualities and naturalites of synthesized speeches.

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BST Thin Film Multi-Layer Capacitors

  • Choi, Woo Sung;Kang, Min-Gyu;Ju, Byeong-Kwon;Yoon, Seok-Jin;Kang, Chong-Yun
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.319-319
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    • 2013
  • Even though the fabrication methods of metal oxide based thin film capacitor have been well established such as RF sputtering, Sol-gel, metal organic chemical vapor deposition (MOCVD), ion beam assisted deposition (IBAD) and pulsed laser deposition (PLD), an applicable capacitor of printed circuit board (PCB) has not realized yet by these methods. Barium Strontium Titanate (BST) and other high-k ceramic oxides are important materials used in integrated passive devices, multi-chip modules (MCM), high-density interconnect, and chip-scale packaging. Thin film multi-layer technology is strongly demanded for having high capacitance (120 nF/$mm^2$). In this study, we suggest novel multi-layer thin film capacitor design and fabrication technology utilized by plasma assisted deposition and photolithography processes. Ba0.6Sr0.4TiO3 (BST) was used for the dielectric material since it has high dielectric constant and low dielectric loss. 5-layered BST and Pt thin films with multi-layer sandwich structures were formed on Pt/Ti/$SiO_2$/Si substrate by RF-magnetron sputtering and DC-sputtering. Pt electrodes and BST layers were patterned to reveal internal electrodes by photolithography. SiO2 passivation layer was deposited by plasma-enhanced chemical vapor deposition (PE-CVD). The passivation layer plays an important role to prevent short connection between the electrodes. It was patterned to create holes for the connection between internal electrodes and external electrodes by reactive-ion etching (RIE). External contact pads were formed by Pt electrodes. The microstructure and dielectric characteristics of the capacitors were investigated by scanning electron microscopy (SEM) and impedance analyzer, respectively. In conclusion, the 0402 sized thin film multi-layer capacitors have been demonstrated, which have capacitance of 10 nF. They are expected to be used for decoupling purpose and have been fabricated with high yield.

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Wireless Impedance-Based SUM for Bolted Connections via Multiple PZT-Interfaces

  • Nguyen, Khac-Duy;Kim, Jeong-Tae
    • Journal of the Korean Society for Nondestructive Testing
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    • v.31 no.3
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    • pp.246-259
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    • 2011
  • This study presents a structural health monitoring (SHM) method for bolted connections by using multi-channel wireless impedance sensor nodes and multiple PZT-interfaces. To achieve the objective, the following approaches are implemented. Firstly, a PZT-interface is designed to monitor bolt loosening in bolted connection based on variation of electro-mechanical(EM) impedance signatures. Secondly, a wireless impedance sensor node is designed for autonomous, cost-efficient and multi-channel monitoring. For the sensor platform, Imote2 is selected on the basis of its high operating speed, low power requirement and large storage memory. Finally, the performance of the wireless sensor node and the PZT-interfaces is experimentally evaluated for a bolt-connection model Damage monitoring method using root mean square deviation(RMSD) index of EM impedance signatures is utilized to estimate the strength of the bolted joint.