• Communications for Statistical Applications and Methods
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• v.14 no.1
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• pp.71-80
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• 2007

The present paper investigates estimation of a scale parameter of a gamma distribution using a loss function that reflects both goodness of fit and precision of estimation. The Bayes and empirical Bayes estimators rotative to balanced loss functions (BLFs) are derived and optimality of some estimators are studied.

• Communications for Statistical Applications and Methods
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• v.14 no.2
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• pp.345-353
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• 2007

A Bayesian estimation of the Nakagami-m fading parameter is developed. Bayesian estimation is performed by Gibbs sampling, including adaptive rejection sampling. A Monte Carlo study shows that the Bayesian estimators proposed outperform any other estimators reported elsewhere in the sense of bias, variance, and root mean squared error.

• Communications for Statistical Applications and Methods
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• v.11 no.2
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• pp.419-433
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• 2004

We suggest the modified computing algorithm for raking ratio estimation under the assumption that the population total is partially known, and the sample total is completely known about survey variable in contingency table. We show that the proposed estimation procedure is useful to estimate the population cell count in this situation through an empirical study.

• International Journal of Internet, Broadcasting and Communication
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• v.6 no.2
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• pp.10-12
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• 2014

This work is based on the motion estimation to handle the ill-posed nature. The algorithm used in this study that performs the motion estimation for overlapped block is used to calculate with using pixel of neighborhood block with higher correlation and present block by considering the correlation level of neighborhood block. The proposed method shows in a significant improvement in the quality of the mothion field when comparing the conventional methods.

• Communications for Statistical Applications and Methods
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• v.7 no.3
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• pp.699-709
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• 2000

The constrained maximum likelihood estimation of the number of trials in several binomial populations under order restriction, such as simple order, is discussed. The estimation procedure is based on, so called, pool adjacent violators algorithm. Three handy estimators are given and their performances are compared using an artificial example.

• Fire Science and Engineering
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• v.10 no.2
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• pp.13-19
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• 1996

An estimation methodology, based on statistics and numerical method, has been developed for estimating the upper explosive limits(UEL) of paraffinic and olefinic hydrocarbon compounds. With proposed method, the UEL has been calculated for 24 paraffinic and 10 olefinic hydrocarbon compounds. The estimated the UEL agree with the experimental values within a few percent. A comparisond with four other methods avaiable in the literature are also presented. It is hoped eventually that this method will permit estimation of the UEL with improved accuracy and broader application for other compounds.

• International Journal of Highway Engineering
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• v.16 no.3
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• pp.119-129
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• 2014

PURPOSES : This investigational survey is to observe a proper spatial aggregation method for path travel time estimation using the hi-pass DSRC system. METHODS : The links which connect the nodes of section detectors location are used for path travel time estimation traditionally. It makes some problem such as increasing accumulation errors and processing times. In this background, the new links composition methods for spatial aggregation are considered by using some types of nodes as IC, JC, RSE combination. Path travel times estimated by new aggregation methods are compared with PBM travel times by MAE, MAPE and statistical hypothesis tests. RESULTS : The results of minimum sample size and missing rate for 5 minutes aggregation interval are satisfied except for JC link path travel time in Seoul TG~Kuemho JC. Thus, it was additionally observed for minimum sample size satisfaction. In 15, 30 minutes and 1 hour aggregation intervals, all conditions are satisfied by the minimum sample size criteria. For accuracy test and statistical hypothesis test, it has been proved that RSE, Conzone, IC, JC links have equivalent errors and statistical characteristics. CONCLUSIONS : There are some errors between the PBM and the LBM methods that come from dropping vehicles by rest areas. Consequently, this survey result means each of links compositions are available for the estimation of path travel time when PBM vehicles are missed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.6C
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• pp.530-538
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• 2010

In this paper, estimation methods of cell searching and DoA (Direction of Arrival) for mobile relay stations with a uniform linear array are proposed. The proposed methods can improve the performance of cell searching and DoA estimation by removing the effect of STOs when there exist symbol timing offsets (STOs) between the signals received from adjacent base stations,. Also, the proposed methods can improve the performance of DoA estimation significantly when there exists Doppler frequency shift caused by movement of the mobile relay station. The performances and computational complexities of the proposed cell searching and DoA methods are evaluated by computer simulation under Mobile WiMAX environments.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.10
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• pp.1155-1162
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• 2004

This paper is the forth paper of several companion papers which compare the method of Air-Fuel ratio determination. In the previous work, various AFR calculations were performed for various fuels and the results were compared with each other. The comparison, however, were limited to numerical value and estimation of each equation or method was insufficient. In this paper, the overall estimation of the methods was attempted. Also, the method of trouble shooting of instrumentation was presented. Through the estimation of methods, it is concluded that the Eltinge method contains inherently the most perfect thermal dissociation model as far as the exhaust composition is concerned; therefore, this might be regarded as the most general equation of AFR determination among the existing ones. The others might be considered as approximate form. In addition, the mal-distribution factor in Eltinge method is qualitatively equivalent to thermal dissociation chemical equilibrium constant K. Lastly, it is illustrated that all instrumentation error, including the sampling line leakage, can be easily detected through the analyzing the exhaust component on the Eltinge chart.

• Journal of Environmental Science International
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• v.13 no.7
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• pp.703-710
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• 2004

Petroleum refineries have been considered as an important emission source for atmospheric volatile hazardous air pollutants(HAPs). The emission source includes petroleum refinery processes and process equipment. The control strategy for volatile HAPs requires emission estimations of these pollutants. However, systematic methods of volatile HAPs emission from petroleum refineries have not yet been established. Accordingly, present study surveyed the estimation method of volatile HAPs emitted from the petroleum refinery processes and process equipment. The emission estimation methods for the petroleum refinery processes are applied for 11 petroleum refining facilities: fluidized catalytic cracking, thermal cracking, moving bed catalytic cracking, compressed engine, blowdown system, vacuum distilled column condensator, natural gas or distilled boiler, natural gas or distilled heater, oil boiler, oil heater and flare. Four emission estimation methods applied for the petroleum refinery process equipment are as follows: average emission factor approach, screening ranges approach, EPA correlation approach and unit-specific correlation approach. The process equipment for which emission factors are available are valves, pump seals, connectors, flanges and open-ended lines.