• 제목/요약/키워드: Token

검색결과 602건 처리시간 0.026초

페리네트를 이용한 필드버스 시스템의 성능 해석 (Performance analysis of fieldbus systems using Petri net)

  • 박홍성;이재수;홍성수
    • 제어로봇시스템학회논문지
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    • 제2권3호
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    • pp.220-228
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    • 1996
  • This paper presents a extended stochastic Petri net (ESPN) model for CTN(Circulated Token with No duration) service in the data link layer of IEC/ISA fieldbus. It is assumed that a station on the fieldbus has a specified minimum token holding time, a finite capacity buffer, and one transmitter queue with the highest priority. The mean transmission (or service) time at a station and the mean token rotation time for the symmetric fieldbus system atr derived using the presented SPN model and the moment generating function. These performance measures are represented in terms of the minimum token holding time, the number of stations, the arrival rate of messages, and the mean length of messages. The presented performance measure are validated by computer simulations.

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토큰버스 프로토콜의 우선순위기능에서 대시시간의 분산 (Variance of waiting time in the priority scheme of token bus protocols)

  • Hong, Seung-Ho
    • 전자공학회논문지A
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    • 제32A권5호
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    • pp.42-53
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    • 1995
  • Token bus protocols have been sidely accepted for Medium Access Control (MAC) in real-time networks such as those used in factory automation, distributed process control, nuclear power plant, aircraft and spacecraft. Token bus protocols provide timer-controlled priority mechanism, which offers multiple level of privilege of medium access to different type of traffic. This paper presents and approximate analytical model for the evaluation of variance of waiting time in the time-controlled proiority scheme of token bus protocols. Token bus system is assumed to be operated with singe-service discipline which is the practical case of real-time networks such as those used in distributed process control and factory automations. The approximate analytical model is validated by comparison with the simulation resuls.

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H.264/AVC 동영상 압축 표준에서 Coeff_token 부호화를 위한 효율적임 메모리 구조 설계 (Design of Efficient Memory Architecture for Coeff_Token Encoding in H.264/AVC Video Coding Standard)

  • 문용호;박경춘;하석운
    • 대한임베디드공학회논문지
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    • 제5권2호
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    • pp.77-83
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    • 2010
  • In this paper, we propose an efficient memory architecture for coeff_token encoding in H.264/AVC standard. The VLCTs used to encode the coeff_token syntax element are implemented with the memory. In general, the size of memory must be reduced because it affects the cost and operation speed of the system. Based on the analysis for the codewords in VLCTs, new memory architecture is designed in this paper. The proposed memory architecture results in about 24% memory saving, compared to the conventional memory architecture.

Real Ethernet Protocol

  • Park, Hong-Seong;Jung, Myong-Soon;Kang, Weon-Joon
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.118-118
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    • 2000
  • This paper suggests the methodology to guarantee the rea1-time service over Ethernet and TCP/IP and to solve the problems such as re-transmission due to collision and platform-transparency and independence. This paper proposes a new mechanism called Real-time Ethernet protocol combined the centralized medium control mechanism with the token passing mechanism. The centralized medium control mechanism is used to get the token, the right to transmit the data, and the token passing mechanism is used to return the token to the token controller and to transmit data within the specified time interval. The proposed Real-Time Ethernet Protocol is based on Java and Java RMI(Remote Method Invocation). The presented protocol is believed to work enough in real-time applications considering latency occurred due to the Java RMI, which is less small than data transmission time.

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Applying Token Tagging to Augment Dataset for Automatic Program Repair

  • Hu, Huimin;Lee, Byungjeong
    • Journal of Information Processing Systems
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    • 제18권5호
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    • pp.628-636
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    • 2022
  • Automatic program repair (APR) techniques focus on automatically repairing bugs in programs and providing correct patches for developers, which have been investigated for decades. However, most studies have limitations in repairing complex bugs. To overcome these limitations, we developed an approach that augments datasets by utilizing token tagging and applying machine learning techniques for APR. First, to alleviate the data insufficiency problem, we augmented datasets by extracting all the methods (buggy and non-buggy methods) in the program source code and conducting token tagging on non-buggy methods. Second, we fed the preprocessed code into the model as an input for training. Finally, we evaluated the performance of the proposed approach by comparing it with the baselines. The results show that the proposed approach is efficient for augmenting datasets using token tagging and is promising for APR.

Token's function and role for securing ecosystem

  • Yoo, Soonduck
    • International Journal of Advanced Culture Technology
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    • 제8권1호
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    • pp.128-134
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    • 2020
  • The purpose of this study is to investigate the role and function of tokens to form a healthy blockchain-based ecosystem. Tokens must be constructed in a way that enhances their desired behavior to grow into a healthy token economy. The actions required of ecosystem participants in designing tokens should enable each individual to receive appropriate incentives (rewards) and encourage voluntary participation in taking this action. Also, all ecosystem participants must design to make the token ecosystem self-sustainable by generating profits. For example, in Bitcoin's proof-of-work method, mining is designed as a desirable behavior. Token-based services should be designed to induce multiple engagements, to design penalties for undesirable behavior, and to take into account evolutionary development potentials. Besides, the economic value of the entire token ecosystem will increase if the value that is designed and designed to take into account the revolutionary Innovation Possibility is greater than the reward amount paid to tokens. This study will contribute to presenting relevant service model by presenting how to design tokens and criteria when establishing blockchain-based service model. Future research is needed to discover new facts through a detailed comparative analysis between Tokennomics models.

토큰 코히런스 프로토콜을 위한 경서열 트렌지언트 요청 처리 방법 (New Transient Request with Loose Ordering for Token Coherence Protocol)

  • 박윤경;김대영
    • 대한전기학회논문지:시스템및제어부문D
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    • 제54권10호
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    • pp.615-619
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    • 2005
  • Token coherence protocol has many good reasons against snooping/directory-based protocol in terms of latency, bandwidth, and complexity. Token counting easily maintains correctness of the protocol without global ordering of request which is basis of other dominant cache coherence protocols. But this lack of global ordering causes starvation which is not happening in snooping/directory-based protocols. Token coherence protocol solves this problem by providing an emergency mechanism called persistent request. It enforces other processors in the competition (or accessing same shared memory block, to give up their tokens to feed a starving processor. However, as the number of processors grows in a system, the frequency of starvation occurrence increases. In other words, the situation where persistent request occurs becomes too frequent to be emergent. As the frequency of persistent requests increases, not only the cost of each persistent matters since it is based on broadcasting to all processors, but also the increased traffic of persistent requests will saturate the bandwidth of multiprocessor interconnection network. This paper proposes a new request mechanism that defines order of requests to reduce occurrence of persistent requests. This ordering mechanism has been designed to be decentralized since centralized mechanism in both snooping-based protocol and directory-based protocol is one of primary reasons why token coherence protocol has advantage in terms of latency and bandwidth against these two dominant Protocols.

Effects of base token for stimuli manipulation on the perception of Korean stops among native and non-native listeners

  • Oh, Eunjin
    • 말소리와 음성과학
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    • 제12권1호
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    • pp.43-50
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    • 2020
  • This study investigated whether listeners' perceptual patterns varied according to base token selected for stimuli manipulation. Voice onset time (VOT) and fundamental frequency (F0) values were orthogonally manipulated, each in seven steps, using naturally produced words that contained a lenis (/kan/) and an aspirated (/khan/) stop in Seoul Korean. Both native and non-native groups showed significantly higher numbers of aspirated responses for the stimuli constructed with /khan/, evidencing the use of minor cues left in the stimuli after manipulation. For the native group the use of the VOT and F0 cues in the stop categorization did not differ depending on whether the base token included the lenis or aspirated stop, indicating that the results of previous studies remain tenable that investigated the relative importance of the acoustic cues in the native listener perception of the Korean stop contrasts by using one base token for manipulating perceptual stimuli. For the non-native group, the use patterns of the F0 cue differed as a function of base token selected. Some findings indicated that listeners used alternative cues to identify the stop contrast when major cues sound ambiguous. The use of the manipulated VOT and F0 cues by the non-native group was not native-like, suggesting that non-native listeners may have perceived the minor cues as stable in the context of the manipulated cue combinations.

보안토큰의 취약성/보안요구사항 분석 및 CC v3.1 기반 보호프로파일 개발 (Vulnerability and Security Requirement Analysis on Security Token and Protection Profile Development based on Common Criteria Version 3.1)

  • 곽진;홍순원;이완석
    • 정보보호학회논문지
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    • 제18권2호
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    • pp.139-150
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    • 2008
  • 최근, 공공기관을 비롯한 금융기관 및 기업들은 안전한 시스템관리 및 사용자 신원확인을 위해 OTP, 스마트카드, USB 인증토큰 등의 보안토큰을 도입하고 있다. 그러나 최근 들어 이런 제품들에 대한 취약성이 소개되었다. 따라서 본 논문에서는 국내 외 보안토큰 표준화 및 개발 동향을 살펴보고, 보안토큰의 취약성, 공격방법 등의 분석을 통해 보안토큰이 일반적으로 갖춰야 할 보안기능과 보안 요구사항을 도출하고, 이를 바탕으로 CC v3.1 기반 보안토큰 보호프로파일을 개발한다.

무선 네트워크에서 비디오 스트리밍의 버퍼 오버플로우를 해결하기 위한 토큰버킷 기법 (The Token Bucket Scheme to solve Buffer Overflow of Video Streaming in Wireless Network)

  • 이현노;김동회
    • 디지털콘텐츠학회 논문지
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    • 제16권3호
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    • pp.365-371
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    • 2015
  • 무선 네트워크 환경에서 수신측의 재생 버퍼에 있는 비디오 스트리밍 패킷 정보량은 무선 네트워크 상태에 따라 가변될 수 있다. 이것의 영향으로 예상치 못한 지연과 지터가 발생하고 그에 따라 군집적인 비디오 트래픽이 생성이 될 수 있다. 수신측 재생 버퍼에 들어오는 버퍼 정보량이 특정 버퍼량보다 많아지면 버퍼 오버플로우(buffer overflow)문제가 발생한다. 목적지 수신 버퍼에서 비디오 스트리밍을 서비스 할 경우 이러한 오버플로우 문제는 비디오 스트리밍 서비스의 스킵(skip)현상 및 패킷 손실로 인한 영상의 손실을 일으켜 비디오 품질 저하 및 재생의 불연속성을 발생시킨다. 따라서 본 논문에서는 무선 네트워크 환경에서 비디오 스트리밍의 버퍼 오버플로우 문제를 해결하기 위하여 군집적인 트래픽을 대비하기 위한 토큰 버킷(Token Bucket)기법을 수신측 단말에 적용하고 그 효과를 분석하였다. NS-2(Network Simulation-2)와 JSVM(Joint Scalable Video Model)을 이용하는 모의실험 결과는 제안하는 방법이 오버플로우 발생 횟수, 패킷 손실 비율, PSNR(Peak Signal to Noise Ratio)측면에서 우수함을 확인할 수 있었다.