• Title/Summary/Keyword: Technical Issue

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Vibration Analysis of Rotary Compressor based on Vibration Intensity (진동인텐시티를 이용한 로타리압축기 진동 해석)

  • 이장우;김영종;안병하
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2003.05a
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    • pp.973-978
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    • 2003
  • Vibration and Noise of air conditioner are entirely determined by compressor vibration. Compressor vibration transmitted to the enclosure of air conditioner or Pipes connected compressor with heat exchanger. Enclosure generated noise and vibration. Therefore, the analysis of compressor vibration analysis is considered significant technical issue. For the reduction of vibration of compressor, it is necessary to grasp correctly vibration transmission paths and excitation sources in the compressor shell. Because, shell (Surface of compressor) shows whole vibration characteristic of compressor mechanism. In this paper, vibration intensity was applied to measure vibration energy flow on the shell. From this technique, it is possible to catch the path of vibration propagation along the one cycle and the location of vibration energy sources may change with time on the shell.

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Activation Strategies of Non-government Certification Using SWOT/AHP Analysis (SWOT/AHP 분석을 이용한 민간인증제도 활성화 전략)

  • Goh, Hyun-Woo
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.32 no.2
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    • pp.104-111
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    • 2009
  • Recently, it is becoming the big issue internationally where the safety problem of the industrial product including the foodstuffs. The way is able to construct the trust of the consumer that the external specialized agency independently operating confirms what production process of the product keep a standard or a technical regulation. This is conformity assessment. In the many countries, agencies entrusted government authority do conformity assessment. Specially, 'certification' in one form of conformity assessment process is operating a certification system at the government and the non-government body in Korea. Also non-government certification is fixed by trusted system from consumer. He has to prepare a competitive power in liberalization time, so need the countermeasure urgently. This study purpose that develops strategy so as to activating of non-government certification system in gist of the origination called 'self-control.' I present activation strategies using SWOT/AHP analysis.

Investigation of CDMA Air Interface and Protocols

  • Kim, Sun-Young;Song, Pyeong-Jung;Kim, Jin-Up;Lee, Hyuck-Jae
    • ETRI Journal
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    • v.19 no.3
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    • pp.303-315
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    • 1997
  • This appendix deals with the Korean air interface standard, TTA-62, for CDMA Mobile Systems, (CMS) [1]-[2]. The standard has been set up by Telecommunications Technology Association (TTA) which is a standardization organization in Korea [3]. This standard is an important specification that should be determined prior to the development of a digital cellular system. The CMS has been developed on the basis of this standard and the papers published in this special issue are the results of the CMS development. This appendix also describes the technical commonality of these papers. It covers the outline of the air interface and protocol specifications. The outline includes its major characteristics, radio protocol architecture, functionalties, and call processing. A comparison is also given between TTA-62 and IS-95[4], a North American digital cellular standard.

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Trends in Betavoltaic Battery Technology (베타전지 기술동향 분석)

  • Kang, T.W.;Choi, B.G.;Park, S.M.;Park, K.H.;Lee, J.J.;Kang, S.W.
    • Electronics and Telecommunications Trends
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    • v.32 no.6
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    • pp.40-47
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    • 2017
  • One of the main technical constraints of a conventional battery is the limited lifetime of electric energy supplied. With self-power generation using an internal radioisotope as an emitter of beta particles, and a PN-junction semiconductor as an absorber of the beta particles, a betavoltaic battery can provide electric energy to electric devices in a semi-permanent manner. Hence, a betavoltaic battery can be adopted as the solution to the power source issue of IoT devices placed in locations that people cannot easily access, such as in the deep sea, a desert, and space, and requiring a long operation time without an electrical charging. This paper covers the current trends in betavoltaic batteries including issues regarding their technology, application, and patents.

Advanced Manufacturing Technologies on the World Wide Web: Methodologies and Application Techniques (World Wide Web 상의 첨단 생산 기술: 방법론과 응용기술)

  • Kim, Seong-Jip;Kim, Nak-Hyun;Yang, Tae-Kon
    • IE interfaces
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    • v.9 no.3
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    • pp.306-316
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    • 1996
  • The easily use of WWW and Web browser of INTERNET makes the world our stage. But when we search for the information and resource that we want, the information supplied by search engine (e.g., Yahoo, Lycos, WebCrawler, Alta Vista) is inadequate to acquire the necessary and related information of research issues. This paper surveys AMT(Advanced Manufacturing Technology) which is the research topics recently on the WWW(WorLd Wide Web) and provides searching methods and information for academic research, technical report, proceedings, software, etc. It also briefly surveys WWW-VL(Virtual Library) and reviews the major three technology, CALS (Commerce At Light Speed), AMS(Agile Manufacturing System), CE(Concurrent Engineering), that is recently the focus of the research issue of Industrial Engineer.

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A Cultural Dimensions Model based on Smart Phone Applications

  • Oh, Jung-Min;Moon, Nam-Mee
    • Journal of Information Processing Systems
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    • v.7 no.1
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    • pp.209-220
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    • 2011
  • One of the major factors influencing the phenomenal growth of the smart phone market is the active development applications based on open environments. Despite difficulties in finding and downloading applications due to the small screens and inconvenient interfaces of smart phones, users download applications nearly every day. Such user behavior patterns indicate the significance of smart phone applications. So far, studies on applications have focused mainly on technical approaches, including recommendation systems. Meanwhile, the issue of culture, as an aspect of user characteristics regarding smart phone use, remains largely unexamined throughout the world. Hence, the present study attempts to analyze the highest ranked smart phone applications downloaded and paid for that are ranked the highest in 10 countries (Korea, Japan, China, India, the UK, USA, Indonesia, Canada, France, and Mexico) and we then derive the CDSC (Cultural Dimensions Score of Content) for these applications. The results derived are, then, mapped to the cultural dimensions model to determine the CISC (Cultural Index Score for Country). Further, culturally significant differences in smart phone environments are identified using MDS analysis.

A Comparative Study on Policies Related To Trust Services in e-Business (전자상거래 신뢰서비스를 활성화시키기 위한 선진국들의 정책에 관한 비교 연구)

  • Lee, Jung-Woo;Lee, Jong-Sung
    • Journal of Digital Convergence
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    • v.1 no.1
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    • pp.213-234
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    • 2003
  • "Trust" becomes a focal issue in e-business. Unlike traditional business environment, virtual situation requires new trust-ensuring mechanism other than face-to-face meetings and other related means of confirmation. Many countries are trying to foster trust services industry in order to increase e-business transactions and activities. This paper compares and contrasts these countries' policies on trust services. Conclusions of this comparative research includes: (1) trust services industry will be tightly integrated horizontally and increase their scope vertically towards trust in business sense over and beyond the mere technical level trust, (2) necessity of reciprocal trust authentication exchange is calling for an international standard in a near future, and (3) two different types of policies are under development: government-led and industry-led. Advantages and disadvantages of different approaches are presented with details of legal implications and structures of operations.

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Impact Assessment of Plug-in Hybrid Electric Vehicles on Electric Utilities (플러그인 하이브리드 자동차의 시장 형성 시의 전력망에의 영향 분석)

  • Roh, Chul-Woo;Kim, Min-Soo
    • Proceedings of the KSME Conference
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    • 2008.11b
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    • pp.2001-2006
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    • 2008
  • The most concerning issue of these days is the energy crisis by increasing threat of dependency on foreign oil and its volatility itself. In the situations, the PHEV is drawing attention for the next generation's car which could give a chance to decrease the dependency on foreign oil. As well as, the Korean electric power infrastructure is a strategic national asset that is under utilized most of the time. With the proper changes in the operational paradigm, it could generate and deliver necessary energy to charge the PHEVs which could penetrate the market within few years. In doing so, it would reduce greenhouse gas emissions, improve the economics of the electricity industry, and reduce the energy dependency. This paper investigate the technical potential and impacts of using the existing idle capacity of the electric infrastructure in conjunction with the emerging PHEVs technology to meet the majority of daily energy needs of the Korean LDV fleet.

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Design of Pitot-Tube Configuration Using CFD Analysis and Optimization Techniques (CFD 해석 및 최적화 기법을 이용한 피토관 형상설계)

  • Kim, Do-Jun;Cheon, Young-Seong;Myong, Rho-Shin;Park, Chan-Woo;Cho, Tae-Hwan;Park, Young-Min;Choi, In-Ho
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.32 no.5
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    • pp.392-399
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    • 2008
  • Accurate measurement of speed and altitude of flying vehicles in air data system remains a critical technical issue. A highly reliable Pitot-static probe is required to obtain air data such as total pressure and static pressure. In this study, an analysis of the characteristics of flowfield around the Pitot-static probe was performed by using a Navier-Stokes CFD code. In addition, for the purpose of finding an optimal configuration, a technique based on the response surface method is applied to the problem with design parameters including shape of the nose section and cone angle. It is shown that the optimal configuration fulfills the MIL specification in wider range of high angles of attack.

An Efficient Repository Model for Online Software Education

  • Lee, Won Joo;Baek, Yuncheol;Yang, Byung Seok
    • Journal of the Korea Society of Computer and Information
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    • v.21 no.12
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    • pp.219-226
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    • 2016
  • In this paper, we propose an efficient repository model for online software education. The software education of app development consists of 7 stages: coding & debugging, submit, collaboration, review, validate, deployment, certification. Proposed repository model supports all 7 stages efficiently. In the coding & debugging stage, the students repeat coding and debugging of source. In the submit stage, the output of previous process such as source codes, project, and videos, are uploaded to repository server. In the collaboration stage, other students or experts can optimize or upgrade version of source code, project, and videos stored in the repository. In the review stage, mentors can review and send feedbacks to students. In the validate stage, the specialists validate the source code, project, and the videos. In the deployment stage, the verified source code, project, and videos are deployed. In the certification stage, the source code, project, and the videos are evaluated to issue the certificate.