• Title/Summary/Keyword: Distributor

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PFC and Zero Torque Control of SRM for EV Battery Charging (EV용 충전 인덕터용 PFC 및 제로 토크제어)

  • Rashidi, A.;Namazi, M.M.;Saghaian-nezhad, S.M.;Lee, D.H.;Ahn, J.W
    • Proceedings of the KIEE Conference
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    • 2015.07a
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    • pp.652-654
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    • 2015
  • Integrated switched reluctance motor drive as an electric vehicle battery charger is presented in this paper. The SRM, which is used as the traction power in the driving mode, is used in the charge circuit to improve the power factor of charging system. The charging circuit can share the power switches of the asymmetric converter and phase windings of SRM to charge the battery, and can reduce the size and cost of the system in the plug-in system. To keep the rotor at standstill, zero torque control method is proposed. Since the inductances of the SRM windings are not same at any stop position, the charger controller controls the reference current to satisfy the total charging current with PFC and zero torque condition. A novel cubic equation method is proposed as a current reference distributor of the charging controller. Simulations are performed by MATLAB software and results satisfy the Effectiveness of proposed battery charging system.

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Role of network geometry on fluid displacement in microfluidic color-changing windows

  • Ucar, Ahmet Burak;Velev, Orlin D.;Koo, Hyung-Jun
    • Smart Structures and Systems
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    • v.18 no.5
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    • pp.865-884
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    • 2016
  • We have previously demonstrated a microfluidic elastomer, which changes apparent color and could have potential applications in smart windows. The practical use of such functional microfluidic systems requires rapid and uniform fluid displacement throughout the channel network with minimal amount of liquid supply. The goal of this simulation study is to design various microfluidic networks for similar applications including, but not limited to, the color-switching windows and compare the liquid displacement speed and efficiency of the designs. We numerically simulate and analyze the liquid displacement in the microfluidic networks with serpentine, parallel and lattice channel configurations, as well as their modified versions with wide or tapered distributor and collector channels. The data are analyzed on the basis of numerical criteria defined to evaluate the performance of the corresponding functional systems. We found that the lattice channel network geometry with the tapered distributors and collectors provides most rapid and uniform fluid displacement with minimum liquid waste. The simulation results could give an important guideline for efficient liquid supply/displacement in emerging functional systems with embedded microfluidic networks.

Design of Subject-based Community Model by Linkage Heterogeneous Content: Focused on Field of Biological Science

  • Ahn, Bu-Young;Kim, Ji-Young;Oh, Chung-Shick;Lee, Myung-Sun
    • International Journal of Contents
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    • v.6 no.3
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    • pp.10-14
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    • 2010
  • Researchers in Korea and elsewhere have carried out a wide variety of important research activities in their respective fields, producing valuable research results. For such diverse research results to be shared and exchanged among researchers working in the same discipline and research subject there needs to be a community environment based on free utilization of information. Against this backdrop, this study seeks to classify and reprocess the reference/factual content owned by the KISTI (Korea Institute of Science and Technology Information), a state-run distributor of information on science and technology, by the different research subjects. It also seeks to develop and provide a community model based on the concepts of open archiving and open access for the researchers specialized in the related fields of research. This community model is developed focusing on the research results from the field of bioscience, where the most extensive studies are currently being conducted. To develop the community model, this study: (a) surveys the current status of the content owned by KISTI; (b) analyzes the patterns and characteristics of biological scientific content among the KISTI-owned content; and (c) designs a web platform where researchers can freely upload/download research results.

A Study on Factors Affecting Turnover Intention of Jewelry Distribution Distributor

  • Lee, Sangki;Lee, Donghae
    • Journal of Distribution Science
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    • v.15 no.9
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    • pp.17-26
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    • 2017
  • Purpose - This study aims to present ways to secure capable employees by examining key factors of internal marketing applicable to the jewelry distribution business and analyzing the relations among organizational commitment, job satisfaction, and turnover intentions among employees who play important roles in jewelry distributors. Research Design, data, and methodology - To examine these research models, samples were collected from 210 individuals working in jewelry distribution companies. The analysis was conducted by the use of a questionnaire method among employees in jewelry distribution companies. SPSS 18.0 were utilized for data analysis. Results - Among internal marketing components of jewelry distribution companies, the two factors - management support and reward system - have positive (+) effect on organizational commitment and while internal communication and education/training have negative (-) effect on employees' turnover intention. Jewelry distribution company employees' job satisfaction and organizational commitment have negative (-) effect on their turnover intention. Conclusions - This is an exploratory study that aims to find out ways to prevent employee turnover in the perspective of jewelry distribution companies' organizational measure - internal marketing. The future study needs to present more sophisticated strategies of internal marketing based on in-depth analysis of specific causes that make employees at jewelry distribution companies leave the occupations.

Satellite Image Watermarking Perspective Distance Decision using Information Tagging of GPS (GPS 정보태깅을 이용한 원근거리 판별 기반의 위성영상 워터마킹)

  • Ahn, Young-Ho;Kim, Jun-Hee;Lee, Suk-Hwan;Moon, Kwang-Seok;Kwon, Ki-Ryong
    • Journal of Korea Multimedia Society
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    • v.15 no.7
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    • pp.837-846
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    • 2012
  • This paper presents a watermarking scheme based on the perspective distance for the secure mash-up service. The proposed scheme embeds the watermark of the location information of satellite image and the user information using edge color histogram, which is dissimilar to general digital image. Therefore, this scheme can trace the illegal distributor and can protect private information of user through the watermarking scheme that is adaptive to satellite image. Experimental results verified that our scheme has the invisibility and also the robustness against geometric attacks of rotation and translation.

Design & Implementation of License-based Digital Rights Management System (라이센스 기반 디지털 저작권 보호 시스템 설계 및 구현)

  • Jeong, Yeon-Jeong;Yoon, Ki-Song;Ryu, Jae-Cheol
    • The KIPS Transactions:PartC
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    • v.11C no.1
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    • pp.55-62
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    • 2004
  • The web-based technology allows anybody who has access to the Internet to get all kinds of information from the World Wide Web. It brings about issues regarding intellectual property and copyright threats. After content is downloaded, no further protection is provided on the content that has been accessed. DRM (Digital Right Management) technologies came out to ensure the protection of copyrighted content and information. In this paper, we propose architecture of license-based digital rights management system for protection of contents and principles' rights such as contents creators, providers, distributors, and uses in contents distribution value-chain over Internet. This system makes on-line processing of all value-chain from creator to purchaser possible, compared with existing DRM products only supporting only limited distribution between distributor and purchaser.

A Design for a Hyperledger Fabric Blockchain-Based Patch-Management System

  • Song, Kyoung-Tack;Kim, Shee-Ihn;Kim, Seung-Hee
    • Journal of Information Processing Systems
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    • v.16 no.2
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    • pp.301-317
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    • 2020
  • An enterprise patch-management system (PMS) typically supplies a single point of failure (SPOF) of centralization structure. However, a Blockchain system offers features of decentralization, transaction integrity, user certification, and a smart chaincode. This study proposes a Hyperledger Fabric Blockchain-based distributed patch-management system and verifies its technological feasibility through prototyping, so that all participating users can be protected from various threats. In particular, by adopting a private chain for patch file set management, it is designed as a Blockchain system that can enhance security, log management, latest status supervision and monitoring functions. In addition, it uses a Hyperledger Fabric that owns a practical Byzantine fault tolerant consensus algorithm, and implements the functions of upload patch file set, download patch file set, and audit patch file history, which are major features of PMS, as a smart contract (chaincode), and verified this operation. The distributed ledger structure of Blockchain-based PMS can be a solution for distributor and client authentication and forgery problems, SPOF problem, and distribution record reliability problem. It not only presents an alternative to dealing with central management server loads and failures, but it also provides a higher level of security and availability.

The Effects of Selective Attributes for PB Food of Convenience Store on Purchase and Mouth-to-mouth Intention

  • Kim, Ki-Pyeong
    • The Korean Journal of Food & Health Convergence
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    • v.3 no.1
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    • pp.1-7
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    • 2017
  • The study has made theoretical system by thesis journals at home and abroad, material of the Association of Convenience Store Industry of Korea, materials of Statistics Korea and reference books. First, the study examined convenience store's brand image, cognized value, quality level, reliability upon brand, structural relation of purchasing intention, and designed models and theses. Second, the first questionnaire consisted of test items of precedent study, and inspected in advance to inspect reliability and appropriateness, and made correction and supplemented problems. Third, SPSS and AMOS statistics were used to conduct empirical analysis and to find out conclusion and implications. In this study, the subject was consumers who visited local convenience stores such as GS25, Seven Eleven and CU last 3 months to buy PB food. Consumers' consumption pattern and culture made change to be reasonable and practical owing to aging society, nuclear family, women's entering into the society, one person household consumer, and convenient and prompt buying to make different consumption pattern and to make change of commodity distribution pattern. Convenience store took action against change of the trend to expand business area by new distribution channels to get another growth source. Private brand (PB) food that was distributor's brand was expanded. The PB product has been competitiveness of food service industry.

Characteristics of Foam Generation in Freshwater and Seawater (담수와 해수에서의 포말 생성 특성)

  • SHIN Jeong-Sik;KIM Byong-Jin;SUH Kuen-Hack
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.37 no.3
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    • pp.179-185
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    • 2004
  • The characteristics of foam generation were assessed for freshwater and seawater using a foam generator. Both in freshwater and seawater, the height of the foam layer increased with initial protein concentrations. The height of the foam layer also increased with pore size of the air distributor. The optimum superficial air velocities (SAV) in freshwater and seawater were 0.84 cm/sec and 0.6 cm/sec, respectively. The height of the foam layer was the highest in pH 3 in freshwater and in the region of pH 5-7 in seawater. The height of the foam layer increased with $NaHCO_3$ concentration in freshwater, and $NaHCO_3$ concentration had little effect in seawater. Removal efficiencies of total suspended solid (TSS) and turbidity decreased with an increase of initial protein concentrations in a batch foam separator both in freshwater and seawater.

A new approach on Chaotic Encryption Process in a MPEG (MPEG 카오스 암호화 과정의 새로운 접근방법)

  • Lee, Dong-Hun;Yun, Byung-Choon;Kim, Deok-Hwan
    • Proceedings of the Korean Information Science Society Conference
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    • 2011.06d
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    • pp.86-89
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    • 2011
  • 현재 인터넷이 생활의 일부로 자리함으로써 인터넷을 통해 수많은 멀티미디어의 교환이 발생하며, 많은 멀티미디어 서비스가 이루어지고 있다. 멀티미디어 서비스를 제공함에 있어 최근 저작권 관리 및 보호의 필요성이 대두되고 있다. 이에 따라 멀티미디어 데이터에 대한 암호기술 개발에 많은 연구가 진행되고 있으며 카오스 사상에 기반 한 암호화 연구가 최근 연구 추세이다. 본 논문은 MPEG(Moving Picture Experts Group) 인코딩 과정에서 1차원 카오스 사상(Map)을 이용하여 인트라 블록을 암호화하는 새로운 방법을 제안하고자 한다. 본 제안 시스템은 MPEG 구조 기반으로 CKD(Chaotic Key Distributor)를 이용하여 확장된 키 값으로 인트라 블록의 0이 아닌 DCT(Discrete Cosine Transform) 계수를 암호화 하는 방법이다. MPEG 인코딩 과정중 DCT 계수는 양자화를 통해 손실이 발생하더라도 비교적 많은 0값을 생성한다. 이는 RLE(Run Length Encoding) 과정에서 압축 효과를 높일 수 있다. 제안하는 방법은 영상 손실을 감수하고 수행한 양자화 과정의 효과를 유지하기 위하여 0이 아닌 DCT 계수만을 암호화 한다. 실험 결과 원본과 암호화된 MPEG의 크기의 변화는 매우 적으며, 인코딩 시간 또한 큰 차이를 보이지 않았다.