• 제목/요약/키워드: fast analysis

검색결과 4,190건 처리시간 0.058초

안전한 NEMO 기반 PMIPv6 네트워크를 위한 빠른 핸드오버를 지원하는 확장 인증기법 (Authentication eXtention Scheme of Fast Handover for Secure NEMO-based PMIPv6 Networks)

  • 임일균;정종필
    • 한국인터넷방송통신학회논문지
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    • 제13권5호
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    • pp.107-119
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    • 2013
  • 본 논문에서는 이동성을 지원하는 NEMO(NEwork MObility)와 네트워크 기반의 PMIPv6(Proxy Mobile IPv6)가 결합된 유 무선 통합 네트워크 환경에서 보안을 강화하고 암호계산과 인증지연 비용을 줄이는 가벼운 키 베이스의 $SK-L^2AS$(Symmetric Key-Based Light-Local Authentication Scheme)인증기법을 제안한다. 또한 PMIPv6에서 핸드오버 지연 단축을 위해 빠른 핸드오버 기법을 적용하였고, 지원되지 않는 전역 이동성을 지원하기 위해 X-FPMIPv6(eXtension of Fast Handover for PMIPv6)으로 확장 개선하였다. 더불어, 인증과 시그널링의 신호 부담을 줄이기 위해서 Piggybacks 방식을 적용하여 SK-L2AS과 X-FPMIPv6을 통합한 AX-FPMIPv6 (Authentication eXtension of Fast Handover for PMIPv6)을 제안한다. 본 논문에서 제안한 AX-FPMIPv6 기법은 성능분석 결과 인증과 핸드오버 지연에서 기존 기법에 비해 성능이 우수하다는 것을 보여준다.

Application of the SCIANTIX fission gas behaviour module to the integral pin performance in sodium fast reactor irradiation conditions

  • Magni, A.;Pizzocri, D.;Luzzi, L.;Lainet, M.;Michel, B.
    • Nuclear Engineering and Technology
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    • 제54권7호
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    • pp.2395-2407
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    • 2022
  • The sodium-cooled fast reactor is among the innovative nuclear technologies selected in the framework of the development of Generation IV concepts, allowing the irradiation of uranium-plutonium mixed oxide fuels (MOX). A fundamental step for the safety assessment of MOX-fuelled pins for fast reactor applications is the evaluation, by means of fuel performance codes, of the integral thermal-mechanical behaviour under irradiation, involving the fission gas behaviour and release in the fuel-cladding gap. This work is dedicated to the performance analysis of an inner-core fuel pin representative of the ASTRID sodium-cooled concept design, selected as case study for the benchmark between the GERMINAL and TRANSURANUS fuel performance codes. The focus is on fission gas-related mechanisms and integral outcomes as predicted by means of the SCIANTIX module (allowing the physics-based treatment of inert gas behaviour and release) coupled to both fuel performance codes. The benchmark activity involves the application of both GERMINAL and TRANSURANUS in their "pre-INSPYRE" versions, i.e., adopting the state-of-the-art recommended correlations available in the codes, compared with the "post-INSPYRE" code results, obtained by implementing novel models for MOX fuel properties and phenomena (SCIANTIX included) developed in the framework of the INSPYRE H2020 Project. The SCIANTIX modelling includes the consideration of burst releases of the fission gas stored at the grain boundaries occurring during power transients of shutdown and start-up, whose effect on a fast reactor fuel concept is analysed. A clear need to further extend and validate the SCIANTIX module for application to fast reactor MOX emerges from this work; nevertheless, the GERMINAL-TRANSURANUS benchmark on the ASTRID case study highlights the achieved code capabilities for fast reactor conditions and paves the way towards the proper application of fuel performance codes to safety evaluations on Generation IV reactor concepts.

미국 소비자의 건강관심도에 따른 패스트푸드 소비가치 차이에 관한 연구 (Consumption Values of Fast Food according to Health Consciousness in American Consumers)

  • 이기원;이영미
    • 대한지역사회영양학회지
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    • 제27권4호
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    • pp.309-320
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    • 2022
  • Objectives: This study aimed to analyze the consumption values of fast foods among American consumers and compare the consumption values according to the levels of health consciousness. Methods: An online survey using a self-administered questionnaire was conducted on 351 American consumers. Based on the median health consciousness score (3.83 out of 5 points), the subjects were classified into the low health-conscious group (Low group) and the high health-conscious group (High group). Factor analysis was used to extract factors for the five consumption values (functional, social, emotional, conditional, and epistemic values). The differences in the consumption values between the two groups were analyzed. Results: A total of 14 factors were extracted for the five consumption values and 9 factors among them (convenience, healthiness, and taste in functional values; health-conscious people, young, busy, obese people, low class, and budget restricted people in social values; guilt in emotional values; accidental situations in conditional values) showed significant differences between the two groups. The Low group had a higher perception of the factor of healthiness (P < 0.001) than the High group. The High group had a relatively higher perception of the factors of convenience (P < 0.001), taste (P < 0.001), and guilt (P < 0.001). In addition, the High group perceived the social values of fast foods more negatively. The High group consumed fast foods less frequently than the Low group and perceived their health status and healthiness of eating habits more positively. Conclusions: The results reveal that the health consciousness level significantly influences consumption value perceptions about fast foods in American consumers. Policymakers and marketers can develop effective strategies based on the results of this study.

SI 엔진의 시동 및 아이들 구간에서의 점화시기에 따른 싸이클별 연소현상에 관한 실험적 연구 (An Experimental Study of Cyclic Combustion Characteristics at Starting and Idling Phase on Spark Ignition Engine)

  • 최성원;최관희;명차리;박심수
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2007년도 춘계학술대회B
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    • pp.3317-3322
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    • 2007
  • THC(Total Hydrocarbon) emissions during cold start and warm-up phase constitute the majority of THC emissions during the FTP-75 mode. As the basic approach to improve the emission performance of Gasoline engine during transient phase, the effect of spark timing retard from MBT on THC emission characteristics is studied by engine test using a Fast response Flame Ionization Detector(FFID). A cyclic analysis of the combustion process shows that high THC emissions are produced first few cycles during the transient phase. This paper presents the results of engine performance and emission of Gasoline engine with various spark timing. consequently, This paper was focused on the combustion phenomena with various spark timing during transient phase which was analyzed by Fast response Flame Ionization Detector (FFID) equipment to measure the cyclic THC emission characteristics.

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패스트푸드 브랜드 개성에 따른 재포지셔닝 전략 (Repositioning Strategies Following Fast Food Brand Personality)

  • 김경희
    • 한국식생활문화학회지
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    • 제31권2호
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    • pp.121-130
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    • 2016
  • This study attempted to understand the fast food brand personality in the domestic dining market to present the repositioning strategies within the competitive market. Positive analysis results were as follows. First, the five brand individualities of 'familiarity', 'passion', 'professionalism', 'reliability', and 'refinement' were derived. Second, the deductions made on perceptions of the population using a Biplot based on the brand personality showed that there were significant differences among the brand personality images of the brands, which were the targets of comparison. Third, there were significant between-group differences in the comparisons of perception among the subgroups according to gender, brand reliability, and brand satisfaction. Fourth, there were significant between-group differences in the consumer fast food brand preferences and ideal point. Such studies can provide information useful for establishing marketing differentiating strategies by grasping the brand personality of competing brands in the market.

안정도 지수와 에너지 마진을 이용한 불안정 발전기의 clustering 법 (A Novel Method for Clustering Critical Generator by using Stability Indices and Energy Margin)

  • 장동환;정연재;전영환;남해곤
    • 대한전기학회논문지:전력기술부문A
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    • 제54권9호
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    • pp.441-448
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    • 2005
  • On-line dynamic security assessment is becoming more and more important for the stable operation of power systems as load level increases. The necessity is getting apparent under Electricity Market environments, as operation of power system is exposed to more various operating conditions. For on-line dynamic security assessment, fast transient stability analysis tool is required for contingency selection. The TEF(Transient Energy Function) method is a good candidate for this purpose. The clustering of critical generators is crucial for the precise and fast calculation of energy margin. In this paper, we propose a new method for fast decision of mode of instability by using stability indices. Case study shows very promising results.

MPEG-7 시각 기술자와 해마 신경망을 이용한 내용기반 검색 (Content-Based Retrieval using MPEG-7 Visual Descriptor and Hippocampal Neural Network)

  • 김영호;강대성
    • 제어로봇시스템학회논문지
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    • 제11권12호
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    • pp.1083-1087
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    • 2005
  • As development of digital technology, many kinds of multimedia data are used variously and requirements for effective use by user are increasing. In order to transfer information fast and precisely what user wants, effective retrieval method is required. As existing multimedia data are impossible to apply the MPEG-1, MPEG-2 and MPEG-4 technologies which are aimed at compression, store and transmission. So MPEG-7 is introduced as a new technology for effective management and retrieval of multimedia data. In this paper, we extract content-based features using color descriptor among the MPEG-7 standardization visual descriptor, and reduce feature data applying PCA(Principal Components Analysis) technique. We model the cerebral cortex and hippocampal neural network in engineering domain, and team content-based feature vectors fast and apply the hippocampal neural network algorithm to compose of optimized feature. And then we present fast and precise retrieval effect when indexing and retrieving.

Secure Pre-authentication Schemes for Fast Handoff in Proxy Mobile IPv6

  • Baek, Jaejong
    • Journal of information and communication convergence engineering
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    • 제14권2호
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    • pp.89-96
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    • 2016
  • In mobile communication, there are various types of handoff for the support of all forms of mobility. Proxy mobile IPv6 (PMIPv6) enables local network-based mobility management of a mobile node without any effect of mobility-related signaling. Recently, PMIPv6 has been considered for supporting mobility management in LTE/SAE-based mobile networks. To support seamless mobility in heterogeneous mobile networks, the overall cost of handoffs needs to be minimized and the procedure should be guaranteed to be secure. However, the reduction of the authentication cost has not been fully investigated to provide seamless connectivity when mobile users perform a handoff between the PMIPv6 domains. This paper proposes secure pre-authentication schemes, completing an authentication procedure before performing a handoff, for a fast handoff in PMIPv6. Analytic models have been used for measuring the authentication latency and for the overhead cost analysis. In addition to providing fast authentication, the proposed pre-authentication schemes can prevent threats such as replay attacks and key exposure.

안정도 지수와 에너지 마진을 이용한 불안정 발전기의 clustering 법 (A Novel Method of Clustering Critical Generator by using Stability Indices and Energy Function)

  • 장동환;정연재;전영환;남해곤
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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    • pp.136-139
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    • 2005
  • On-line dynamic security assessment is becoming more and more important for the stable operation of power systems as load level increases. The necessity is getting apparent under Electricity Market environments due to more various operating conditions. Fast transient stability analysis tool is required for contingency selection. The TEF(Transient Energy Function) method is a good candidate for this purpose. The clustering of critical generators is crucial for the precise and fast calculation of energy margin. In this paper, we propose a new method for fast decision of mode of instability by using stability indices. Case study shows very promising results.

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수해복구 현장 시공사례(영동선 분천${\~}$승부간 각금천 제1, 2교량) (A Case study on a flood disaster restoration work)

  • 신현곤;김지훈;배준현;이주혁
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2004년도 춘계학술대회 논문집
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    • pp.159-164
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    • 2004
  • Recently the unexpected damage is broken out by the unusal change of weather. Misfortune on top of misfortune the typhoon did great damage again before finishing the repair work. And then we should study about the repair work of fast and safety as well as the construction of safety. The paper suggests the case study of a fast disaster restoration work. To minimise the term of repair work which selects Fast Track Method. This work is processed as follows. Temporary resortation is progressed at the same time as the main resortation. And In this paper, technique to evaluate the capacity of bridge is tried to develop by means of FEM analysis.

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