• Journal of Information Processing Systems
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• v.10 no.1
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• pp.36-54
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• 2014

Resource sharing is a major advantage of distributed computing. However, a distributed computing system may have some physical or virtual resource that may be accessible by a single process at a time. The mutual exclusion issue is to ensure that no more than one process at a time is allowed to access some shared resource. The article proposes a token-based mutual exclusion algorithm for the clustered mobile ad hoc networks (MANETs). The mechanism that is adapted to handle token passing at the inter-cluster level is different from that at the intra-cluster level. It makes our algorithm message efficient and thus suitable for MANETs. In the interest of efficiency, we implemented a centralized token passing scheme at the intra-cluster level. The centralized schemes are inherently failure prone. Thus, we have presented an intra-cluster token passing scheme that is able to tolerate a failure. In order to enhance reliability, we applied a distributed token circulation scheme at the inter-cluster level. More importantly, the message complexity of the proposed algorithm is independent of N, which is the total number of nodes in the system. Also, under a heavy load, it turns out to be inversely proportional to n, which is the (average) number of nodes per each cluster. We substantiated our claim with the correctness proof, complexity analysis, and simulation results. In the end, we present a simple approach to make our protocol fault tolerant.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.407-410
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• 1997

This paper analytically derives the variance of service time of a station in the symmetric IEEE 802.4 token bus network with single access class and finite buffer capacity. This performance measure is represented in terms of the total number of stations, the token hold time, the arrival rate of frames, the service rate, and other parameters. Using computer simulations, presented performance measure is validated.

• Proceedings of the KIEE Conference
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• 2006.10c
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• pp.111-113
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• 2006

FOUNDATION fieldbus provides scheduling and token-passing services for cyclic and sporadic data respectively. In this paper, we evaluate the delay performance of token-passing mechanism in FOUNDATION fieldbus network system using an experimental model. This paper introduces a method of developing an experimental model which consists of 10 nodes of FOUNDATION fieldbus communication device. Using the experimental model, we evaluate the delay performance of time-critical and time-available data with respect to change of TTRT parameter.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10a
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• pp.37-42
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• 1992

The main purpose of the paper is to derive asymptotic formulae for performance characteristics(throughput, delay) of large-scale token-passing network with buffered stations and to optimize the buffer capacity with respect to the probability of data generation. We consider two versions of token-passing network: uniform and nonuniform token-passing time interval. All results obtained are supported by simulations.

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.430-433
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• 1999

Woo[8]proposed dual-token based fault-tolerant scheduling algorithm in multiprocessor environment for resolving the problem of old systems that have a central dispatcher processor. However, this algorithm does not present token allocation algorithm in detail when central dispatcher processor has failed. In this paper, we propose a fault detection algorithm and processor selection algorithm for token allocation when central dispatcher processor has failed.

• Journal of the Korea Society for Simulation
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• v.2 no.1
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• pp.46-54
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• 1993

Analytic and simulation models for prioritized token ring are presented in this paper. Its protocol is based on prioritized token ring with reservation (R-PTR). Since the protocol of the R-PTR is simple and the performance of the R-PTR is not inferior to that of the IEEE-PTR under almost all traffic load environments, we use the R-PTR as our token ring model. By using the properties of Markovian process, the expressions for average throughput and average packet transmission delay are derived. The results obtained from the analytic model are compared with that of the discrete event simulation model.

• Child Health Nursing Research
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• v.6 no.1
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• pp.69-77
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• 2000

Oral medication is the most frequent treatment measure for follow up treatment, which is leading by childrens' parents for them. In medication for preoperational children, they tend to concentrate the result rather than the motivation or cause. So, they frequently refuse medication which has bitter taste. So this study was attempted to develop token economy program which promote children's medication and help their parents, and to evaluate its' effect to construct the experimental ground. This study was a quasi experimental study under the nonequivalent control group posttest only design. The subjects of this study were 36 children who were aged 3-6 years and admitted pediatric ward because of their respiratory disease. Token economy program was consisted of cartoon record paper with stickers which expresses the better medication is taken the more germs die, and gift was given for back up reinforcer. To evaluate this program, time for oral medication was measured to both experimental group and control group. To determine the effect of the program, the data were analyzed by the SAS 6.12 program with t-test. The results of this study were as follows: 1. Between experimental group and control group, there was no significant difference (t=-1.2411, P=0.2374). Therefore, the hypothesis of this study was rejected. In conclusion, the token economy program for follow up care didn't change the children's behavior of oral medication. But it was found that the cartoon on recording paper gave a pleasure to participated children. Parents who were in experimental group expressed their appreciation for token economy program. So it can be said that the token economy program for follow up care was effective in inducing the children's pleasure and parents' satisfaction even though it wasn't successful in experiment. If the measuring tools for token economy program was made with well planned design and high reliability, it can be improved the effectiveness of that To develope the theoretical bases of nursing care, the well planned programs and measuring tools for them should be developed.

• Journal of Platform Technology
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• v.11 no.5
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• pp.37-48
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• 2023

Since the announcement of the Financial Services Commission's 'Token Securities Issuance and Distribution System Improvement Plan' in February 2023, financial institutions, securities firms, and blockchain companies have been actively considering implementing IT platforms, but they are facing difficulties in selecting IT platforms for token securities because related legal regulations have not yet been clearly established. As a result, the need for rational and systematic criteria for the selection of blockchain-based token securities IT platforms has emerged, and this study explores and evaluates the key factors of token securities IT platform selection. Four factors were identified as the top-level factors, including 'maturity of the platform', 'operation and management of the platform', 'cost of introducing and maintaining the platform', and 'regulatory compliance for token securities', and 17 factors were identified as sub-level factors, including 'diversity', 'user authentication management', 'Adoption Costs', and 'financial regulations'. Among the 17 sub-factors, 'government financial regulation' and 'personal information protection' are selected as important factors, and the results of this study can help related organizations and financial companies make strategic decisions by providing systematic decision-making criteria for selecting token securities IT platforms.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.54.3-54
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• 2002

$\textbullet$ Introduction $\textbullet$ Token Passing Protocol : Profibus-FMS $\textbullet$ Performance Model of Profibus Token Passing Protocol $\textbullet$ Calculation of Communication Delay in Performance Model $\textbullet$ Summaries and Conclusions

• Proceedings of the Korean Information Science Society Conference
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• 2008.06b
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• pp.464-468
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• 2008

본 논문은, H,264/AVC 비디오 코덱의 저전력용 CAVLC 디코더를 위한 coeff_token 회로의 면적을 최적화 한 설계를 제시한다. CAVLC 디코더의 전력 소비를 줄이기 위해서 coeff_token 회로에서의 메모리 참조 빈도수를 줄이는 여러 가지 방법이 제안되어 왔다. 본 논문에서는 기존의 저전력용으로 개발된 coeff_token 회로 중 가장 전력 소비가 낮은 방식의 메모리 구조와 수식 계산 회로를 변형시켜서 전력 소비를 같은 수준으로 유지하면서도 면적을 더욱 줄이는 방법을 제안한다. 본 연구결과를 삼성 0.18 um 공정을 대상으로 합성한 결과 기존 방식에 비해서 1.1% 면적이 줄어드는 성과를 거두었다.