• Title/Summary/Keyword: Multi-functionality

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The Study of Auxiliary Power Unit for locomotive (철도차량용 보조전원장치에 관한 연구)

  • Jeong, Han-Dong;Lee, Won-Cheol;Lee, Sang-Seok;Kim, Tae-Hwan;Won, Chung-Yuen
    • Proceedings of the KSR Conference
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    • 2009.05b
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    • pp.615-619
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    • 2009
  • There are many increasing demands for efficient high power density of auxiliary power unit(APU) for high speed traction application. Many techniques have been proposed to measure the voltage flicker on the traditional pulse width modulation(PWM) inverter. This paper proposes a novel functionality of the static inverter on the APU to mitigate the voltage flicker and regulate the output voltage. A new control algorithm for the inverter based on the Hilbert transform(HT) is presented. The HT is employed as an effective technique for tracking the voltage flicker levels in APU systems. Simulation results are provided to verify the tracking capabilities of the HT and to evaluate the performance of the proposed DG interface for multi-function operation.

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3-D Hetero-Integration Technologies for Multifunctional Convergence Systems

  • Lee, Kang-Wook
    • Journal of the Microelectronics and Packaging Society
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    • v.22 no.2
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    • pp.11-19
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    • 2015
  • Since CMOS device scaling has stalled, three-dimensional (3-D) integration allows extending Moore's law to ever high density, higher functionality, higher performance, and more diversed materials and devices to be integrated with lower cost. 3-D integration has many benefits such as increased multi-functionality, increased performance, increased data bandwidth, reduced power, small form factor, reduced packaging volume, because it vertically stacks multiple materials, technologies, and functional components such as processor, memory, sensors, logic, analog, and power ICs into one stacked chip. Anticipated applications start with memory, handheld devices, and high-performance computers and especially extend to multifunctional convengence systems such as cloud networking for internet of things, exascale computing for big data server, electrical vehicle system for future automotive, radioactivity safety system, energy harvesting system and, wireless implantable medical system by flexible heterogeneous integrations involving CMOS, MEMS, sensors and photonic circuits. However, heterogeneous integration of different functional devices has many technical challenges owing to various types of size, thickness, and substrate of different functional devices, because they were fabricated by different technologies. This paper describes new 3-D heterogeneous integration technologies of chip self-assembling stacking and 3-D heterogeneous opto-electronics integration, backside TSV fabrication developed by Tohoku University for multifunctional convergence systems. The paper introduce a high speed sensing, highly parallel processing image sensor system comprising a 3-D stacked image sensor with extremely fast signal sensing and processing speed and a 3-D stacked microprocessor with a self-test and self-repair function for autonomous driving assist fabricated by 3-D heterogeneous integration technologies.

Perceived challenges in fashion shopping online: Scale development and validation (온라인 패션 쇼핑 시 도전감의 척도 개발 및 타당성 연구)

  • Shim, Soo In
    • The Research Journal of the Costume Culture
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    • v.24 no.6
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    • pp.709-724
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    • 2016
  • The purpose of this study is to develop a multi-dimensional scale measuring consumers' perceived challenge in shopping fashion products online, and to verify its validity and reliability. Relevant literature is first reviewed to identify possible dimensions of perceived challenge. Next, Study 1 is conducted in order to explore the dimensions empirically and to see whether the dimensions that emerged were consistent with prior findings. A total of 190 responses to an open-ended question was qualitatively analyzed by using content analysis. The findings of Study 1 generate 26 items reflecting four dimensions (i.e., product knowledge, previous experience, website functionality, and product availability), which correspond to the dimensions suggested in literature review. Study 2 is subsequently conducted to refine the items so that the perceived challenge scale establishes cross-validation, convergent validity, discriminant validity, reliability, and predictive validity. A total of 238 responses is quantitatively analyzed by using exploratory factor analysis, confirmatory factor analysis, and structural equation modeling. In the results of Study 2, the perceived challenge scale is found to consist of a total of 16 items reflecting three dimensions: E-commerce Challenge (corresponding to Previous Experience reported in Study 1), Retailer Challenge (corresponding to Website Functionality), and Product Challenge (corresponding to Product Knowledge); all Product Availability items have been eliminated through the item refinement process. Specifically, E-commerce Challenge and Retailer Challenge are found to predict flow, supporting flow theory, while Product Challenge fails to lead to flow significantly. Implications, limitations, and suggestions for future studies are also discussed.

A Creative Solution of Distributed Modular Systems for Building Ubiquitous Heterogeneous Robotic Applications

  • Ngo Trung Dung;Lund Henrik Hautop
    • Proceedings of the IEEK Conference
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    • summer
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    • pp.410-415
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    • 2004
  • Employing knowledge of adaptive possibilities of agents in multi-agents system, we have explored new aspects of distributed modular systems for building ubiquitous heterogeneous robotic systems using intelligent building blocks (I-BLOCKS) [1] as reconfigurable modules. This paper describes early technological approaches related to technical design, experimental developments and evaluation of adaptive processing and information interaction among I-BLOCKS allowing users to easily develop modular robotic systems. The processing technology presented in this paper is embedded inside each $DUPLO^1$ brick by microprocessor as well as selected sensors and actuators in addition. Behaviors of an I-BLOCKS modular structure are defined by the internal processing functionality of each I-Block in such structure and communication capacities between I-BLOCKS. Users of the I-BLOCKS system can easily do 'programming by building' and thereby create specific functionalities of a modular robotic structure of intelligent artefacts without the need to learn and use traditional programming language. From investigating different effects of modern artificial intelligence, I-BLOCKS we have developed might possibly contain potential possibilities for developing modular robotic system with different types of morphology, functionality and behavior. To assess these potential I-BLOCKS possibilities, the paper presents a limited range of different experimental scenarios in which I-BLOCKS have been used to set-up reconfigurable modular robots. The paper also reports briefly about earlier experiments of I-BLOCKS created on users' natural inspiration by a just defined concept of modular artefacts.

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Multi-channel QoS scheduling algorithm in IEEE 802.15.4e (IEEE 802.15.4e 멀티 채널 QoS 스케줄링 알고리즘)

  • Wu, Hyuk;Kim, Hak-Kyu;Lee, Dong-Jun;Kang, Ho-Yong
    • Journal of Advanced Navigation Technology
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    • v.15 no.5
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    • pp.764-773
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    • 2011
  • IEEE 802.15.4 is a standard for LWPAN based on TDMA. IEEE 802.15.4 has not been used widely because of restrictions on the QoS, scalability, and reliability. IEEE 802.15.4 utilizes GTS for one-hop QoS transmission. However GTS is not an effective method to satisfy QoS in multi-hop environments. Currently IEEE 802.15.4e, an extended version of IEEE 802.15.4 MAC sub-layer, is being developed to satisfy more diverse performance requirements than IEEE 802.15.4. IEEE 802.15.4e provides muti-hop QoS transmission functionality and uses multiple frequency channels. In this paper, a multi-channel TDMA scheduling scheme is proposed to satisfy end-to-end transmission delay in IEEE 802.15.4e. The performance of the proposed scheme is evaluated using simulation.

Design of Intra Prediction Circuit for HEVC and H.264 Multi-decoder Supporting UHD Images (UHD 영상을 지원하는 HEVC 및 H.264 멀티 디코더 용 인트라 예측 회로 설계)

  • Yu, Sanghyun;Cho, Kyeongsoon
    • Journal of the Institute of Electronics and Information Engineers
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    • v.53 no.12
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    • pp.50-56
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    • 2016
  • This paper proposes the architecture and design of intra prediction circuit for a multi-decoder supporting UHD images. The proposed circuit supports not only the latest video compression standard HEVC but also H.264. In addition to the basic function of performing intra prediction, this circuit has the capability of performing the reference sample filter operation defined in the H.264 standard, and the smoothing and strong sample filter operations defined in the HEVC standard. We reduced the circuit size by sharing the circuit blocks for common operations and internal storage, and improved the circuit performance by parallel processing. The proposed circuit was described at RTL using Verilog HDL and its functionality was verified by using NC-Verilog of Cadence. The RTL circuit was synthesized by using Design Compiler of Synopsys and 130nm standard cell library. The synthesized gate-level circuit consists of 69,694 gates and processes 100 ~ 280 frames per second for 4K-UHD HEVC images at the maximum operation frequency of 157MHz.

Basic Renewal Directions of Boundary Barriers in Rural Villages by Multi-attribute Decision Making (다요소의사결정법에 의한 농촌마을담장정비의 기본방향)

  • Lim, Jong-Hyeon;Choi, Soo-Myung;Yang, So-Yeol;Cho, Eun-Jung
    • Journal of Korean Society of Rural Planning
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    • v.19 no.4
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    • pp.307-317
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    • 2013
  • The value and functionality of boundary barriers in rural villages have been neglected in the aspects as the buffer zone(boundary barrier) that links between the inside space(housing site) and the outside space(road). On this understanding, this study evaluated conservation value, economical efficiency and durability by the types and materials of the boundary barriers in rural village through Multi-attribute Decision Making. By applying to the current situations of boundary barriers on total 21 case study villages, each factor value was measured. And using Matrix Analysis Technique, the boundary barriers are classified into 4 types and the improvement ways for each type were proposed. As a result, the durability of boundary barriers in rural villages showed similarity value(more than 0.85 out of 1). But economical efficiency of those was low(less than 0.5 out of 1) and those functionalities were very lacking(about 0.3 out of 1). In the conclusion, the maintenance of boundary barriers in rural villages requires the policy that is able to complement conservation value and economical efficiency and is proper to the characteristic of each village. These renewable policies would contribute to the increase of the value of rural amenity as well as creation of economical and social value.

Development of the Frequency Synthesizer for Multi-function Radar (다기능 레이더용 주파수합성기 개발)

  • Yi, Hui-min;Choi, Jae-hung;Han, Il-tak
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.22 no.8
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    • pp.1099-1106
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    • 2018
  • In this paper, we developed and then analyzed the specifications of the frequency synthesizer which was applied to long range MFR (Multi-function Radar). These specifications were able to guarantee the functions and performance of MFR. MFR was the radar system that used phase array for electronically scanning. This frequency synthesizer made various frequency signals including to STALO (Stable Local Oscillator) for MFR. By analyzing the MFR requirements, we choose the optimal frequency synthesis method and then we got the best performance and functionality including to physical size for this system. We designed and fabricated DDS (Direct Digital Synthesizer)-driven Offset-PLL (Phase Locked Loop) synthesizer to meet the requirements which were low phase noise, fast switching time and low spurious. This synthesizer had less than -131dBc/Hz@100kHz phase noise and less than $4.1{\mu}s$ switching time, respectively.

Hybrid polymer-quantum dot based single active layer structured multi-functional device (Organic Bistable Device, LED and Photovoltaic Cell)

  • Son, Dong-Ick;Kwon, Byoung-Wook;Park, Dong-Hee;Kim, Tae-Whan;Choi, Won-Kook
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.02a
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    • pp.97-97
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    • 2010
  • We demonstrate the hybrid polymer-quantum dot based multi-functional device (Organic bistable devices, Light-emitting diode, and Photovoltaic cell) with a single active-layer structure consisting of CdSe/ZnS semiconductor quantum-dots (QDs) dispersed in a poly N-vinylcarbazole (PVK) and 1,3,5-tirs- (N-phenylbenzimidazol-2-yl) benzene (TPBi) fabricated on indium-tin-oxide (ITO)/glass substrate by using a simple spin coating technique. The multi-functionality of the device as Organic bistable device (OBD), Light Emitting Diode (LED), and Photovoltaic cell can be successfully achieved by adding an electron transport layer (ETL) TPBi to OBD for attaining the functions of LED and Photovoltaic cell in which the lowest unoccupied molecular orbital (LUMO) level of TPBi is positioned at the energy level between the conduction band of CdSe/ZnS and LiF/Al electrode (band-gap engineering). Through transmission electron microscopy (TEM) study, the active layer of the device has a p-i-n structure of a consolidated core-shell structure in which semiconductor QDs are uniformly and isotropically adsorbed on the surface of a p-type polymer core and the n-type small molecular organic materials surround the semiconductor QDs.

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Influence of Alkylation on Interface and Thermal Conductivity of Multi-walled Carbon Nanotubes-reinforced Epoxy Resin (알킬화가 다중벽탄소나노튜브로 강인화된 에폭시수지의 계면 및 열전도도에 미치는 영향)

  • Heo, Gun-Young;Rhee, Kyong-Yop;Park, Soo-Jin
    • Polymer(Korea)
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    • v.35 no.6
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    • pp.548-552
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    • 2011
  • Two functionalization methods, i.e., acid treatment and chemical amidation were performed to prepare the functionalized multi-walled carbon nanotubes (MWCNT), and the properties of epoxy/functionalized MWCNT composites were investigated and compared. Fourier transform infrared spectroscopy (FTIR) was used to confirm the surface functionality of the MWCNT obtained by the functionalization methods. The effects of the MWCNT functionalization on the interface and thermal conductivity were studied by zeta potential analyzer, scanning electron microscope and thermal conductivity analyzer. From these results, it was confirmed that the thermal conductivity of the epoxy/MWCNT composites could be increased by grafting with dodecylamine. This could be interpreted by relatively strong dispersion forces of the grafting MWCNT with dodecylamine in DGEBF epoxy resin. These results were in good agreement with the results that the zeta potential value of the grafting MWCNT with dodecylamine has a higher negative value than that of MWCNT with acid treatment.