• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.3
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• pp.475-481
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• 2009

The frequency and probability of deadlock are influential factors in the design of algorithms for deadlock. However, little work has been done in this area because it's not easy to analyze how factors such as the characteristics of process or resource, resource request and release patterns, or the number of process affect the occurrence of deadlock. This study was designed to reduce remarkably the number of state by adapting the model 'state (a,b)t' to represent the resource allocation state, as well as to include the effect of resource error rate and recovery rate in the system analysis. Various formulas about deadlock occurrence were resulted in this study such as the average time interval of deadlock, the probability that a process requesting a resource waits or deadlocks, and the probability that a request deadlocks in a cycle of length 2.

• Journal of information and communication convergence engineering
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• v.4 no.4
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• pp.131-135
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• 2006

In this paper, we discusses that the theoretical analysis is made for the performance of FS MC-CDMA by the aid of the Nakagami fading channels and the block error probabilities of the FS MC-CDMA in Nakagami fading channel are presented. The channel fading speed, slow or fast, is considered in evaluating block error probabilities. The effectiveness of diversity combining in improving block error performance is examined.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.30B no.9
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• pp.54-63
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• 1993

Quantization error, generated by the quantization process of an image, is inherent in computer vision. Because, especially in stereo vision, the quantization error in a 2-D image results in position errors in the reconstructed 3-D scene, it is necessary to analyze it mathematically. In this paper, the analysis of the probability density function (pdf) of quantization error for a line-based stereo matching scheme is presented. We show that the theoretical pdf of quantization error in the reconstructed 3-D position information has more general form than the conventional analysis for pixel-based stereo matching schemes. Computer simulation is observed to surpport the theoretical distribution.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.4B
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• pp.308-315
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• 2002

This paper proposes new probability models for wideband code division multiple access (W-CDMA) signals. The performance of a W-CDMA system is evaluated by calculating the average bit error rate(BER) which is derived from the probability distribution of the W-CDMA receiver output. If a probability model of the receiver output is available, the performance evaluation becomes much simpler and it enables diverse analyses of the system for channel coding and other purposes. In this paper, probability distributions of W-CDMA signals, more specifically those of the receiver output, are represented as Rayleigh and noncentral chi distribution, considering various bandwidths and channel environments. The adequacy of a probability model is verified by chi-square test of 1% significance level. The BER of the system obtained from the simulation results is compared to that obtained from the probability model to demonstrate the usefulness of the proposed models.

• Journal of Navigation and Port Research
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• v.43 no.1
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• pp.1-8
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• 2019

Identifying behavioral errors of seafarers that have led to marine accidents is a basis for research into prevention or mitigation of marine accidents. The purpose of this study is to estimate the optimal probability distribution function needed to model behavioral errors of crew members into three behaviors (i.e., Skill-, Rule-, Knowledge-based). Through use of behavioral data obtained from previous accidents, we estimated the optimal probability distribution function for the three behavioral errors and verified the significance between the probability values derived from the probability distribution function. Maximum Likelihood Estimation (MLE) was applied to the probability distribution function estimation and variance analysis (ANOVA) used for the significance test. The obtained experimental results show that the probability distribution function with the smallest error can be estimated for each of the three behavioral errors for eight types of marine accidents. The statistical significance of the three behavioral errors for eight types of marine accidents calculated using the probability distribution function was observed. In addition, behavioral errors were also found to significantly affect marine accidents. The results of this study can be applied to predicting marine accidents caused by behavioral errors.

• ETRI Journal
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• v.32 no.6
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• pp.965-968
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• 2010

In this letter, we derive the distribution functions of five ratios involving two correlated Gaussian random variables by using the rotation of Cartesian coordinates. The results can be used in evaluating the various probability performances of wireless communications systems.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.9
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• pp.4109-4115
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• 2014

Background: Accurate assessment of disease progression requires proper understanding of natural disease process which is often hidden and unobservable. For this purpose, disease status should be clearly detected. But in most diseases it is not possible to detect such status. This study, therefore, aims to present a model which both investigates the unobservable disease process and considers the error probability in diagnosis of disease states. Materials and Methods: Data from 330 patients with gastric cancer undergoing surgery at the Iran Cancer Institute from 1995 to 1999 were analyzed. Moreover, to estimate and assess the effect of demographic, diagnostic and clinical factors as well as medical and post-surgical variables on transition rates and the probability of misdiagnosis of relapse, a hidden Markov multi-state model was employed. Results: Classification errors of patients in alive state without a relapse ($e_{21}$) and with a relapse ($e_{12}$) were 0.22 (95% CI: 0.04-0.63) and 0.02 (95% CI: 0.00-0.09), respectively. Only variables of age and number of renewed treatments affected misdiagnosis of relapse. In addition, patient age and distant metastasis were among factors affecting the occurrence of relapse (state1${\rightarrow}$state2) while the number of renewed treatments and the type and extent of surgery had a significant effect on death hazard without relapse (state2${\rightarrow}$state3)and death hazard with relapse (state2${\rightarrow}$state3). Conclusions: A hidden Markov multi-state model provides the possibility of estimating classification error between different states of disease. Moreover, based on this model, factors affecting the probability of this error can be identified and researchers can be helped with understanding the mechanisms of classification error.

• Nuclear Engineering and Technology
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• v.26 no.1
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• pp.9-18
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• 1994

The engineered safeguards of Wolsung nuclear power plant unit 1 contain redundant systems of 2-out-of-3 logic which are not operating under normal conditions but are called upon to act when emergency conditions develop. To ensure their operability, the systems are periodically tested. In this work, we develop the unavailability formulae for 2-out-of-3 logic configurations which take into account the failure probability of the channels tested due to human error in the simultaneous testing scheme. We also develop the model for the probability that the reactor is tripped during the surveillance test due to either system failure or human error. We determined the optimal inspection periods of safety systems, taking into account both the unavailability of the safety system and the probability that the reactor is tripped during the surveillance test. We compared the results with the inspection periods currently used at Wolsung NPP Unit 1. As a result, the inspection periods obtained using a minimum human error (8.24 $\times$ 1$^{-6}$ ) are shorter than those currently used in Wolsung NPP unit 1 whereas the inspection periods obtained using a maximum human error are (4.44 $\times$ 10$^{-4}$ ) longer than those used in Wolsung NPP unit 1.

• Journal of the Korean Institute of Gas
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• v.4 no.2 s.10
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• pp.52-57
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• 2000

This paper suggests the evaluation sheet to ensure the objective and detailed information based on a classification table of PIF (Performance Influencing Factor). And this paper shows the results of HEP(Human Error Probability), using a quantitative method with the evaluated data as a result of estimating the likelihood of . human errors in the gas industry facility together with the evaluation sheet. Finally, these results are programmed to be operated in personal computer so that field workers an apply it in easy and convenient manner. The results of this study offer two key benefits; sharing reliable information on human errors with the Data Base and establishing a strategy to reduce human errors as well as to improve working proficiency.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.19 no.7
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• pp.1224-1233
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• 1994

The error performance of BPSK and QPSK signals in mobile satellite channel is investigated considering nonlinearity of TWTA (Traveling Wave Tube Amplifier) in the presence of AWGN(Additive White Gaussian Noise) on the uplink and downlink paths. It is assumed that the fading on the downlink path forms a Rician distribution. The Rician distribution is approximated by discrete probability values. The values are firstly found by Classical Moment Technique. Finally, the error probability is evaluated using approximate discrete values of Rician distribution and the Gaussian Quadrature Formula.