• 제목/요약/키워드: frequent convergence

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LPG 탱크로리 폭발시 파편 형상에 따른 비산거리 산정에 관한 연구 (A Study on the decision of Scattering distance by Shape of Fragments in LPG Tank lorry Explosion)

  • 이영진;황용우;이익모;문진영
    • 한국방재안전학회논문집
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    • 제10권2호
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    • pp.29-34
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    • 2017
  • LPG는 사고발생시 사람이나 환경에 치명적인 피해를 가져올 수 있으므로 많은 주의가 필요한 물질이다. LPG는 고정시설 뿐 아니라 운송시설에서도 사고가 빈번하게 발생하며, 그 중 LPG 탱크로리의 사고가 가장 많다. LPG 탱크로리가 운송중 전도되었을 때 LP가스는 2상(two phase) 상태로 누출되어, 대부분 기체로 누출되고 일부분 액체로 누출된다. 이때 누출된 기체도 공기보다 무겁기 때문에 아래로 가라앉게 되고, 누출이 계속된다면 증기운을 형성하여 점화원에 의해 폭발할 수도 있다. 본 연구에서는 LPG 탱크로리의 증기운 폭발 사고 발생시 파편에 대한 영향거리를 분석하여 대피거리를 제시함을 목적으로 한다. 파편의 비산반경 산출 결과, 최대 561m 비산하였다. 따라서 LPG 탱크로리의 누출시 대피하여야 하는 거리는 561 m 이상으로 설정하는 것이 필요하다고 판단된다.

사물인터넷 환경을 위한 경량화 키 위탁 기법 (Lightweight Key Escrow Scheme for Internet of Battlefield Things Environment)

  • 뚜언;이민우;임재성
    • 한국정보통신학회논문지
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    • 제26권12호
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    • pp.1863-1871
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    • 2022
  • 4차 산업혁명 시대에는 보안 네트워킹 기술이 국방 무기 체계에서 필수적인 역할을 하고 있다. 정보보안을 위해 암호 기술을 사용한다. 암호 기술의 안전성은 케르크호프의 원칙(Kerchoff's principle)에서 강조하듯 암호 기술 알고리즘이 아닌 암호 기술의 안전한 키 관리에 기반한다. 그러나, 전장 환경에서 무기체계의 잦은 이동으로 인해 네트워크 구조가 변하며 전통적인 중앙 집중식 키 관리 방법을 사용하기가 어렵다. 또한 IoBT(Internet of Battlefield Things) 환경에서 사용되는 각 노드의 시스템 자원은 크기, 용량, 성능이 제한되므로 기존의 키 관리 알고리즘보다 계산량과 복잡도가 적은 경량화 키 관리 시스템이 필요하다. 본 논문은 IoBT 환경을 위한 경량화 방식의 새로운 키 위탁 방식을 제안한다. 제안된 기법의 안전성과 성능을 수치 분석과 시뮬레이션을 통해 검증하였다.

Efficient USN Routing Protocol using Sub-Clustering

  • Jeong, Su-Hyung;Yoo, Hae-Young
    • Journal of information and communication convergence engineering
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    • 제6권4호
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    • pp.466-469
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    • 2008
  • The existing routing protocols in USN environment, PEGASIS is more efficient than LEACH, which is a hierarchical routing protocol, for network configuration based on power consumption. Despite its merit that it can reduce energy consumption per node, however, the PEGASIS protocol also has a weakness that it is less responsive to frequent changes that occur in the configuration of sensor network due to BS nodes that keep changing, which is a typical characteristic of the sensor network. To address this problem, this paper proposes to select sub-cluster heads and have them serve as intermediate nodes. This paper presents and analyses that this method can resolve the aforementioned problem of the PEGASIS algorithm.

IoT Industry & Security Technology Trends

  • Park, Se-Hwan;Park, Jong-Kyu
    • International journal of advanced smart convergence
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    • 제5권3호
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    • pp.27-31
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    • 2016
  • High-tech industries in a state well enough to troubleshoot hacking information introduction a big barrier to delay the growth of the market related to IoT(Internet of Things) as is likely to be on the rise. This early on, security issues introduced in the solution, a comprehensive solution, including the institutional laws/precautions needed. Recent examples of frequent security threats while IoT is the biggest issue of introducing state-of-the-art industry information due to the vulnerable security hacking. This high-tech industries in order to bridge the information responsible for the target attribute, target range, and the protection of security and how to protect the subject, IoT environment (domestic industrial environment) considering the approach is needed. IoTs with health care and a wide variety of services, such as wearable devices emerge. This ensures that RFID/USN-based P2P/P2M/M2M connection is the implementation of the community. In this study, the issue on the high-tech industrial information and the vulnerable security issues of IoT are described.

The Design of an Efficient Proxy-Based Framework for Mobile Cloud Computing

  • Zhang, Zhijun;Lim, HyoTaek;Lee, Hoon Jae
    • Journal of information and communication convergence engineering
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    • 제13권1호
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    • pp.15-20
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    • 2015
  • The limited battery power in the mobile environment, lack of sufficient wireless bandwidth, limited resources of mobile terminals, and frequent breakdowns of the wireless network have become major hurdles in the development of mobile cloud computing (MCC). In order to solve the abovementioned problems, This paper propose a proxy-based MCC framework by adding a proxy server between mobile devices and cloud services to optimize the access to cloud services by mobile devices on the network transmission, application support, and service mode levels. Finally, we verify the effectiveness of the developed framework through an experimental analysis. This framework can ensure that mobile users have efficient access to cloud services.

Analysis of Success Factors for Mobile Commerce using Text Mining and PLS Regression

  • Kim, Yong-Hwan;Kim, Ja-Hee;Park, Ji hoon;Lee, Seung-Jun
    • 한국컴퓨터정보학회논문지
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    • 제21권11호
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    • pp.127-134
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    • 2016
  • In this paper, we propose factors that influence on the mobile commerce satisfaction conducted by data mining and a PLS regression analysis. We extracted the most frequent words from mobile application reviews in which there are a large number of user's requests. We employed the content analysis to condense the large number of texts. We took a survey with the categories by which data are condensed and specified as factors that influence on the mobile commerce satisfaction. To avoid multicollinearity, we employed a PLS regression analysis instead of using a multiple regression analysis. Discovered factors that are potential consequences of customer satisfaction from direct requests by customers, the result may be an appropriate indicator for the mobile commerce market to improve its services.

A Brief Overview of Wireless Power Transfer Techniques

  • Kshatri, Dinesh Baniya;Shrestha, Surendra;Shrestha, Bhanu
    • International journal of advanced smart convergence
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    • 제4권2호
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    • pp.1-5
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    • 2015
  • The necessity to distribute energy wirelessly has been spurred by the tremendous growth in the use of portable devices. Mobile devices have become ubiquitous and the circuits within them have been optimized to consume extremely low amounts of power. Such portable electronic sets are in constant use and the frequent need to recharge them; using conventional wired mechanisms have hindered the mobility of users. Wireless transmission of energy to power-up devices has been proposed since the days of Tesla and since then many theories and methods have been invented. This paper discusses some of those techniques briefly.

Accelerating RFID Tag Identification Processes with Frame Size Constraint Relaxation

  • Park, Young-Jae;Kim, Young-Beom
    • Journal of information and communication convergence engineering
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    • 제10권3호
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    • pp.242-247
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    • 2012
  • In the determination of suitable frame sizes associated with dynamic framed slotted Aloha used in radio frequency identification tag identification processes, the widely imposed constraint $L=2^Q$ often yields inappropriate values deviating far from the optimal values, while a straightforward use of the estimated optimal frame sizes causes frequent restarts of read procedures, both resulting in long identification delays. Taking a trade-off, in this paper, we propose a new method for determining effective frame sizes where the effective frame size changes in a multiple of a predetermined step size, namely ${\Delta}$. Through computer simulations, we show that the proposed scheme works fairly well in terms of identification delay.

A Clinical History Recording Management Scheme on the Multimedia Telemedicine

  • Kim Seok-Soo
    • Journal of information and communication convergence engineering
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    • 제2권3호
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    • pp.157-160
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    • 2004
  • The paper's suggestion is about hereditary facts between family members. Diagnosing patients from the point of patients temporary conditions, and so performing primitive examinations and treatments, can lead not only to frequent wrong diagnoses, and to huge medical expenses and times to the patients, but even to critical situation of patients or taking lives away. As a means to cut these cases down to a minimum, sharing medical treatment information between family members is suggested. This approach makes possible understanding physical constitution and environment between family members, and can result in bringing a faster treatment effect if some family member suffers from a similar disease. This approach, since a participation in a family membership effectuates all of family members, can minimize the membership fees, thus enabling inter-family health care on a home doctor basis.

Current issues on Requirement Traceability Mechanism for Software Organization of the 4th Industrial Revolution

  • Kim, Janghwan;Kim, R. Young Chul
    • International journal of advanced smart convergence
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    • 제9권4호
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    • pp.167-172
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    • 2020
  • In the 4th industrial revolution, there are many projects for diverse software applications of smart city environments. Most of the stakeholders focus on considering software quality for their developed software. Nobody doesn't guarantee requirement satisfaction after complete development. At this time, we can only work on user acceptance testing for requirement satisfaction on frequently changing requirements. Why keeps the requirement traceability? This traceability is to identify risks related to requirements, to assure correct software development based on customer requirements. To solve this, we are researching how to implement requirement traceability across each artifact's relationship to each activity of a whole development lifecycle.