• Title/Summary/Keyword: communication mode

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Macroblock-based Adaptive Interpolation Filter Method for Improving Coding Efficiency in H.264/AVC (H.264/AVC에서 부호화 효율 개선을 위한 매크로 블록 기반 적응 보간 필터 방법)

  • Yoon, Kun-Su;Kim, Jae-Ho
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.44 no.5
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    • pp.73-83
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    • 2007
  • In this paper, we propose macroblock(MB)-based adaptive interpolation filter method for improving coding efficiency in H.264/AVC. In the proposed method, nine separable two-dimensional(2D) interpolation filters are applied for precisely compensating motions in various directions. The optimal cost function which considers the bit rate and distortion for coding the MB is defined. The filter is adaptively selected per MB for minimizing the defined cost function. In the experimental results, the proposed method shows more excellent in coding efficiency than the conventional methods for the various standard $QCIF(176{\times}144)/CIF(352{\times}288)$ video test sequences. It leads to about 6.25%(1 reference frame) and 3.46%(5 reference frames) bit rate reduction on average compared to the H.264/AVC.

Concerns of Home Economics Teachers on Ohio's Work and Family Life Curriculum (미국 오하이오주의 실천적 문제 중심 모형을 적용한“일과 가족생활 교육과정”에 대한 가정과 교사의 관심도)

  • 채정현
    • Journal of the Korean Home Economics Association
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    • v.34 no.4
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    • pp.327-343
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    • 1996
  • The objective of this study were 1) to determine the stages of concern of HE teachers about the practical problem-based curriculum approach, as illustrated by the Ohio's Work and Family Life Curriculum (W&FLC); 2) to determine the relationships between home economics (HE) teacher's stages of concern about W&FLC and personal and professional characteristics of HE teachers; and 3) to determine aspects of interest about the practical problem-based curriculum approach, such as the Ohio W&FLC. Respondents in this study were 225 HE teachers. The data were collected during the in-service teacher training sessions after presentation about W&FLC. Concerns Based Adoption Model (CBAM) was modified to provide a conceptual framework for this study. Frequencies, SD, mean, mode, range were used to determine the stages of concern of HE teachers. To determine the relationships between stages of concerns and personal and professional characteristics of HE teachers, coefficient of Chi-Square contingency tables was used. Content analysis was used to determine aspects of interest about the practical problem-bsed curriculum approach, such as W&FLC. The median of the stages of HE teachers' concerns about W&FLC was Stage 1, Information Stage. About 60% of HE teachers were interested in learning more details about W&FLC. Chi-square revealed no statistically significant relationships between stages of concerns about W&FLC and characteristics of HE teachers. Content analysis was used to determine aspects of interest about W&FLC of HE teachers. Nine categories were found: content, teaching strategies, implementation of the curriculum, philosophical framework, how to adopt W&FLC, resource materials, students' outcomes, in-service teacher training, and HE teacher organization. The majority of HE teachers were interested in relationships with family and others, resource management, family relationships, personal development, communication skill, family life, creating a self-identity, life planning, roles of family members, homemaking management, child care, and parenting.

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A Study of Mobile Phone Interface Module Development for DGPS (GDPS를 위한 휴대전화 Interface Module 개발에 관한 연구)

  • 김창수;윤희철;이태오;정성훈;임재홍
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2002.05a
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    • pp.197-200
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    • 2002
  • The current Inn technique is many problems that is permission of radio station using RF Wireless Modem, that is influence of geographic obstacle using radio wave, that is frequency interference, that is finiteness of frequency resources. In this paper, we are solved many elements, IM replaces RF Wireless Modem, we suggest transmission technique of correction message using mobile phone, we researched Interface Module development which is linkage of DGPS receiver and mobile phone. IM can transmit correction message passing RS-232 port and modem communication control. IM of base station is initialized RS-232 port and modem to move station for correction message transmission, IM waited response mode. IM of move station is initialized RS-232 port and modem, IM requests hand shaking to base station, completed connection establishment. Users are worked Differential surveying using receiving correction message between mobile phones.

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A Study on the Structure of Polarization Independent GaInAs/GaInAsP/InP Semiconductor Optical Amplifier (편광 비의존성 GaInAs/GaInAsP/InP 반도체 광 증폭기 구조에 관한 연구)

  • Park, Yoon-Ho;Kang, Byung-Kwon;Lee, Seok;Cho, Yong-Sang;Kim, Jeong-Ho;Hwang, Sang-Ku;Hong, Tchang-Hee
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.3 no.3
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    • pp.681-686
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    • 1999
  • In this study, the gain characteristics of the strained structures for SOA were calculated numerically and the optimized strained quantum well for the polarization-insensitive SOA was obtained. The structures used in this calculation were consisted of one, two, and three GaAs Delta layers respectively in the GaInAs(160 $\AA$) well. Moreover the third one was calculated by changing from one mono-layer to three mono-layers in the thichless of GaAs delta layers. This structure enhances the TM mode gain coefficient with good efficiency because the light-hole band is lifted up whereas the heavy-hole band is lowered down. Additionally, The structure of the 3 GaAs delta layers(1 mono layer thickness) shows 3dB gain bandwidth of 85nm in 1.55um wavelength system. This study is expected to be used in making a wide band and polarization-independent semiconductor optical amplifier practically.

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77 GHz Waveguide VCO for Anti-collision Radar Applications (차량 충돌 방지 레이더 시스템 응용을 위한 77 GHz 도파관 전압 조정 발진기)

  • Ryu, Keun-Kwan;Kim, Sung-Chan
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.7
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    • pp.1652-1656
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    • 2014
  • In this work, we demonstrated a 77 GHz waveguide VCO with transition from WR-12 to WR-10 for anti-collision radar applications. The fabricated waveguide VCO consists of a GaAs-based Gunn diode, a varactor diode, a waveguide transition, and two bias posts for operating as a LPF and a resonator. The cavity is designed for fundamental mode at 38.5 GHz and operated at second hormonic of 77 GHz. The waveguide transition has a 1.86 dB of insertion loss and -30.22 dB of S11 at the center frequency of 77 GHz. The fabricated VCO achieves an oscillation bandwidth of 870 MHz. Output power is from 12.0 to 13.75 dBm and phase noise is -100.78 dBc/Hz at 1 MHz offset frequency from the carrier.

Long haul transmission link using a optimized circulating loop for optical wavelength division multiplexing signals (최적화된 반복루프를 이용한 파장분할다중화 광신호 장거리 전송)

  • Choi, Bo-Hun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.7
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    • pp.1757-1763
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    • 2014
  • Optical wavelength division multiplexing signals of eight non-return-to-zero 10 Gb/s channels were transmitted on the long-haul link up to 720 km. The link span was composed of 80 km single mode fiber, dispersion compensation fiber for complete compensation, and EDFAs. A circulating loop method was applied to the link experiment and the loop was optimized for the transmission link. Wavelength-dependent gain variation of EDFA was compensated using EDFAs of opposite gain slopes without expensive gain flattening filters. Average OSNR was aggravated to 22 dB and the worst OSNR channel variation was 9.7 dB after the transmission. It was confirmed by analyzing optical spectra that this OSNR variation was mainly caused by the hole burning effect of EDFA.

Rotational Antenna based Clutter Imaging Algorithm in Helicopter Landing Mode (헬리콥터에 장착된 회전 안테나를 이용한 착륙지형의 이미지 생성 기법)

  • Bae, Chang-Sik;Jeon, Hyeon-Mu;Kim, Jae-Hak;Yang, Hoon-Gee
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.20 no.10
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    • pp.1860-1866
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    • 2016
  • Helicopter-related collision accidents with structures mostly occur at landing, especially in a limited visibility environment, which necessitates some secondary equipment like a radar that can generate stationary clutter image. In this paper, we propose an algorithm that makes an image of stationary ground clutter in two dimensional range and azimuth angle domain. We present a mathematical model for the received signals from each clutter patch in the iso range ring and analyze their clutter and Doppler characteristics, assuming that a helicopter-borne radar has a rotational antenna. We propose a filter structure, which suppresses side lobe signal components while extracting a main lobe signal component, and suggest a solution for a problem stemmed from the filtering process. Finally, by conducting a simulation we show the performance of the suggested imaging algorithm on a two dimensional virtual scenario of the topographic clutter.

Development of CODOG Propulsion System Simulator (CODOG 함정 추진체계 시뮬레이터 개발)

  • Jang, Jae-hee;Shin, Seung-woo;Kim, Min-gon;Oh, Jin-seok
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.21 no.9
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    • pp.1808-1817
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    • 2017
  • Duties required for naval ship such as anti-submarine, anti-ship, and supply, etc are diversified, so the ECS (Enfineering Control System) is required for executing the mission effectively. The ECS monitors and controls the propulsion system in order that naval ship can perform the mission. As the in-country development of ECS is progressed, a test system for ECS is needed, and a naval ship propulsion system simulator based on CODOG was developed on this study. The naval ship propulsion system simulator based on CODOG which is divided into gas turbine model, diesel engine model, reduction gear model and controllable pitch propeller model, simulates to feedback of control commands of ECS. As a result of the experiment, it is able to confirm speed, torque and power, etc. of the gas turbine, diesel engine and shaft according to ECS propulsion mode.

A Development of Multi-Emotional Signal Receiving Modules for Ubiquitous RCP Interaction (유비쿼터스 RCP 상호작용을 위한 다감각 착신기능모듈의 개발)

  • Jang Kyung-Jun;Jung Yong-Rae;Kim Dong-Wook;Kim Seung-Woo
    • Journal of Institute of Control, Robotics and Systems
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    • v.12 no.1
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    • pp.33-40
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    • 2006
  • We present a new technological concept named RCP (Robotic Cellular Phone), which combines RT and CP. That is an ubiquitous robot. RCP consists of 3 sub-modules, RCP Mobility, RCP interaction, and RCP Integration. RCP Interaction is the main focus of this paper. It is an interactive emotion system which provides CP with multi-emotional signal receiving functionalities. RCP Interaction is linked with communication functions of CP in order to interface between CP and user through a variety of emotional models. It is divided into a tactile, an olfactory and a visual mode. The tactile signal receiving module is designed by patterns and beat frequencies which are made by mechanical-vibration conversion of the musical melody, rhythm and harmony. The olfactory signal receiving module is designed by switching control of perfume-injection nozzles which are able to give the signal receiving to the CP-called user through a special kind of smell according to the CP-calling user. The visual signal receiving module is made by motion control of DC-motored wheel-based system which can inform the CP-called user of the signal receiving through a desired motion according to the CP-calling user. In this paper, a prototype system is developed far multi-emotional signal receiving modes of CP. We describe an overall structure of the system and provide experimental results of the functional modules.

Dynamic Bandwidth Allocation Scheme with Considering Downstream Traffic in EPON (EPON에서 하향 데이터 전송을 고려한 동적 대역폭 할당 방안)

  • Kim Eun-Chul;Lee Kang-Won;Choi Young-Soo;Cho You-Ze
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.42 no.12
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    • pp.37-44
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    • 2005
  • This paper proposes a hybrid scheme for dynamic bandwidth allocation(DBA) in Ethernet passive optical network(EPON), which combines advantages of adaptive cycle and constant cycle-based schemes. The proposed scheme is based on IPACT scheme, but it operates as adaptive cycle or constant cycle mode according to the queue status of optical line terminal(OLT) for downstream transmission. Simulation results showed that the proposed scheme could achieve a similar throughput in downstream transmission to a constant cycle-based DBA scheme, while producing a similar delay performance to the IPACT scheme in upstream transmission.