• Journal of Korean Society for Quality Management
• /
• v.33 no.1
• /
• pp.73-82
• /
• 2005

This article proposes a practical approach, which is based on the concept of the expected squared relative error, that can consider both the prediction quality and the practitioner's subjectivity in simultaneously optimizing multiple responses. Through a case study, multiresponse optimization using the expected squared relative error approach is illustrated, and the SAS program to implement the proposed method is provided.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.23 no.61
• /
• pp.89-98
• /
• 2000

For statistical process control, the process data are collected by the measurement system. But, the measurement system may have instrument error or/and operator error. In the measured values of products, the total observed variance consists of process variance and variance due to error of measurement system. In this paper, we design more practical T-s control chart considering estimated measurement error The effects of measurement error on the expected total cost and design parameters are investigated.

• Journal of Korean Institute of Industrial Engineers
• /
• v.15 no.2
• /
• pp.65-75
• /
• 1989

A general software reliability model is developed, which includes the Jelinski-Moranda model, the Goel-Okumoto model, the Shanthikumar model and the Ross model as special cases. In each of above models estimators of the software failure rate and the number of remaining errors are presented and compared in terms of the expected absolute error loss and the expected squared error loss by a Monte Carlo simulation.

• Journal of information and communication convergence engineering
• /
• v.9 no.2
• /
• pp.183-186
• /
• 2011

In this work, we consider imperfectness of feedback channels in the adaptive transmission scheme which was previously studied with an assumption of error-free feedback channels. New method of mapping the modulation index into the feedback channel symbols and quantifying feedback error over fading channels are proposed. The presented method and results are expected to offer valuable tools for the system designer to efficiently implement adaptive diversity schemes to compensate for the performance degradation due to feedback error.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.46 no.8
• /
• pp.43-49
• /
• 2009

This paper presents a routing mechanism to prolong the lifetime of error-prone wireless sensor networks. The proposed mechanism estimates the amount of energy consumption for communications and the expected residual energy in advance, which is based on the qualities of wireless links. Then, the proposed mechanism selects a path that is expected to have the most residual energy, and sends sensory data along the path. This mechanism reduces energy consumption caused by unnecessary retransmissions and distributes traffic evenly over the network owing to taking error rates into consideration, and extends energy depletion by selecting a path with the maximum of the minimal expected residual energy amounts. The experiment results show that the proposed mechanism prolongs network lifetime, compared to the existing methods.

• Journal of Institute of Control, Robotics and Systems
• /
• v.11 no.7
• /
• pp.644-650
• /
• 2005

The expected positioning accuracies of civil users utilizing modernized GPS and Galileo are derived using the error analysis in this paper. Since, in general, the performance of DLL, PLL and FLL is proportional to chip lengths and wavelengths, the positioning accuracies from various measurements of modernized GPS and Galileo are derived as function of chip length and wavelength. These results are compared with that from GPS Ll measurement. In absolute positioning, compared to GPS C/A code only case, more than 17 times performance improvement is expected when all civil code signals of modernized GPS and Galileo (L1, L2, L5, E1, E5A and E5B) are used. In relative positioning, compared to GPS L1 carrier phase only case, more than 2 times performance improvement is expected when all civil signals of modernized GPS and Calileo are used. Furthermore, the relationship between GDOP and RGDOP in single frequency case is expanded to general case where multiple frequencies and both code and carrier phase measurements are used.

• IE interfaces
• /
• v.7 no.1
• /
• pp.75-80
• /
• 1994

In a recent article, Leon et al. lucidly explained the ideas of the Taguchi two-stage procedure for parameter design optimization, and proposed alternative performance measures called PerMIA to the signal-to-noise ratios. On the other hand, Box proposed an empirical approach to the problem based upon monotone transformations of the performance characteristic(y). This paper develops procedures for parameter design optimization under the assumptions that the expected loss(not necessarily a mean squared error loss) is increasing with respect to the variance of the error in y, and that the mean of y satisfies certain conditions of adjustability. It turns out that the variance of the error in y can play the role of PerMIA, and it is further shown that the derived PerMIA can be adapted to the Box empirical procedure for the minimization of the expected loss in the original metric.

• Communications for Statistical Applications and Methods
• /
• v.17 no.5
• /
• pp.679-688
• /
• 2010

Lee (2010) developed a confidence interval for the difference of binomial proportions in two doubly sampled data subject to false-positive errors. The confidence interval seems to be adequate for a general double sampling model subject to false-positive misclassification. However, in many applications, the false-positive error rates could be the same. On this note, the construction of asymptotic confidence interval is considered when the false-positive error rates are common. The coverage behaviors of nine likelihood based confidence intervals are examined. It is shown that the confidence interval based Rao score with the expected information has good performance in terms of coverage probability and expected width.

• Journal of the Korean Society of Safety
• /
• v.32 no.4
• /
• pp.114-121
• /
• 2017

In order to overcome the limitations of the mobile speed system for 1 lane, this study is used a multi-laser beam to develop a mobile speed measuring system, using a multi-phase beam. By using multi-laser beam, least squares algorithms and speed error processing algorithms were developed to improve speed accordancy and speed error rates compared to conventional mobile speed meters using a single laser beam. A field test showed that 80.0 percent of 3 lane and 87.0 percent of 4 lane were appropriate for the mobile speed system. With the development of the mobile speed measuring system, it is expected to dramatically reduce the accidents caused by the speed of traffic. It is also expected to effectively operate equipment and manage the cost by improving manpower and providing improved enforcement accuracy, by contributing positively to public institution and public affairs.

• Journal of Korean Society for Quality Management
• /
• v.29 no.3
• /
• pp.66-78
• /
• 2001

This paper deals with problem of determining process target value under automated visual inspection(AVI) system. Three independent error sources - digitizing error, illumination error, and positional error - which have a close relationship with the performance of the AVI system, are considered. Assuming that digitizing error is uniformly or normally distributed and illumination and positional errors are normally distributed, respectively, the distribution function for the error of measured lengths is derived when the length of a product is measured by the AVI system. Then, Optimal target values under two error models of AVI system are obtained by minimizing the total expected cost function which consists of give away, rework and penalty cost. To validate two process setting models, AVI system for drinks filling process is made up and test results are discussed.