• Proceedings of the Korean Society for Quality Management Conference
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• 2007.04a
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• pp.461-465
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• 2007

The BMAP/M/N/O queueing system operating in Markovian random environment is investigated. The stationary distribution of the system is calculated. Loss probability and other performance measures are calculated. Numerical experiments which show the necessity of taking into account the influence of random environment and correlation in input flow are presented.

• Journal of Korean Society for Quality Management
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• v.26 no.4
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• pp.65-78
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• 1998

Process capability indices, used to determine whether a production process is capable of producing items within a specified tolerance, have been widely used in process assessments. In this paper, we consider some process capability indices using loss function when process is contaminated normal. Also, we examine some small sample properties related to these estimaters by some simulations.

• Journal of the Korea Safety Management & Science
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• v.3 no.3
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• pp.221-230
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• 2001

The assembly tolerance design methods have applied linear or nonlinear programming methods and used simulation method and search algorithms to optimize the tolerance allocation of each part in an assembly. However, those methods are only considered to the relationship between tolerance and manufacturing cost, which do not consider a quality loss cost for each part tolerance. In this paper, the integrated simulation model used genetic algorithm and the Monte-Carlo simulation method was developed for the allocation of the optimal tolerance considering the manufacturing cost and quality loss cost.

• Journal of Korean Society for Quality Management
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• v.18 no.1
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• pp.77-83
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• 1990

A model for the economic design of an pn control charts with an assignale cause is presented and the loss-cost function for control schemes using these charts is derived. By minimizing this function with respect to the three control variables, namely, the sample size, the sampling interval and acceptance number, the economically optimal control plan can be optained. The article shows what influence increasing or decreasing condition, according to changeability of the size of these factors, of expected cost can have on the economy when an attribute control chart is used.

• Proceedings of the Korea Concrete Institute Conference
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• 1992.04a
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• pp.7-12
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• 1992

The aim of this study is to develop economical High-Strength and High-Quality Concrete, and to assure quality control of Concrete in the field. For this purpose, Five types of Mixing Methods are examined and the relationship between slump loss and slump recovery by transport is studied. As a result, workability and strength are dependent on the Mixing Method, although the Mixing proportions are same, Also, adding admixture in the field is proposed as an alternative to consider the relationship between slump loss and slump recovery.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.16 no.28
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• pp.173-180
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• 1993

This paper is to propose the procedure for improving the level of product specification in statistical process control using loss function. The procedure proposed in this paper is extended to the Taguchi's Quality engineering concept This procedure will be useful in establishing product specification. This paper is aimed to provide customer satisfaction for consumer and quality management for producer.

• Food Science and Preservation
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• v.5 no.2
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• pp.133-137
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• 1998

In order to establish effectiveness of CA storage and adequate CO2 concentration, it was investigated the quality chanties of Singer during CA storage for 150 days at different CO2 concentrations ranging from 3% to 12% and 3% fixed oxygen concentration. Weight loss tend to decrease with increase of CO2 concentrations. Sprouting ratio and the loss of gingerol was shown to be less as CO2 concentration increase but to be more than control stored at 12$^{\circ}C$, 95% RH within the concentration less than 6% CO2.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.23 no.54
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• pp.167-177
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• 2000

The problem of system reliability is very important issue in the nuclear power plant, because the failure of its system brings about extravagant economic loss, environment destruction, and quality loss. This paper therefore proposes a normalized scoring model by the qualitative factors order to evaluate the robust reliability of nuclear power plants under uncertainty. Especially, the qualitative factors including risk, functional, human error, and quality function factors for the robust justification has been also introduced. Finally, the analytical reliability and safety assessment model developed in this paper can be used in the real nuclear power plant.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.2
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• pp.181-187
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• 1984

Lysine is known as a limiting amino acid in rice. In addition, it is considered to be important in that it is easily non-activated by the browning reaction during processing or storage. The present study was designed to utilize a kinetic approach to analyse the effect of temperature and water activity on available lysine loss in rice. Simplified kinetic models were used to obtain the various kinetic parameters for available lysine loss in rice subjected to accelerated shelf-life tests (ASLT). These kinetic parameters were then used to predict protein quality loss under the non-steady state storage. The predicted losses were compared to the actual losses. As expected, available lysine loss was increased with increased temperature and water activity. The activation energies and $Q_{10}$ values for available lysine loss ranged from 4.03 to 5.10 Kcal/ mole and 1.22 to 1.27, respectively, The shelf-lives at $25^{\circ}C$, the time to reach 25% loss of the available lysine, which was derived from the accelerated shelf-life tests showed 67 to 107 days according to $a_w$'s. The amount of loss for the fluctuating condition was greater than that occurring at the mean temperature of $45^{\circ}C$. Actually, the differences in effective temperature for the fluctuating storage were between about 4 and $6^{\circ}C$. In predicting the extent of loss using constant state data, the predicted shelf-lives were 2 to 7 days shorter than the actual storage values.

• The Journal of the Acoustical Society of Korea
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• v.40 no.2
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• pp.176-182
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• 2021

This paper evaluates and compares the performance of the Deep Nerual Network (DNN)-based speech enhancement models according to various loss functions. We used a complex network that can consider the phase information of speech as a baseline model. As the loss function, we consider two types of basic loss functions; the Mean Squared Error (MSE) and the Scale-Invariant Source-to-Noise Ratio (SI-SNR), and two types of perceptual-based loss functions, including the Perceptual Metric for Speech Quality Evaluation (PMSQE) and the Log Mel Spectra (LMS). The performance comparison was performed through objective evaluation and listening tests with outputs obtained using various combinations of the loss functions. Test results show that when a perceptual-based loss function was combined with MSE or SI-SNR, the overall performance is improved, and the perceptual-based loss functions, even exhibiting lower objective scores showed better performance in the listening test.