• Phonetics and Speech Sciences
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• v.15 no.3
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• pp.45-52
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• 2023

Previous studies have established a role for cognitive differences in explaining variability in speech processing across individuals. In the case of perceptual cue weighting in the context of a sound change, studies have produced conflicting results regarding the relationship between executive function and the use of redundant cues. The current study aimed to explore this relationship in acoustic cue weighting during speech production. Forty-one Korean-speaking children read a list of stop-initial words and completed two tests that assess executive function, i.e., Dimensional Change Card Sorting (DCCS) and digit n-back. Voice onset time (VOT) and fundamental frequency (F0) were measured in each word, and analyses were carried out to determine the extent to which children's executive function predicted their use of both informative and less informative cues to the three pairs comprising the Korean three-way stop laryngeal contrast. No evidence was found for a relationship between cognitive ability and acoustic cue weighting in production, which is at odds with previous, albeit conflicting, results for speech perception. While this result may be due to the lack of task demands in the production task used here, it nevertheless expands the empirical ground upon which future work in this area may proceed.

• Journal of the Korean Statistical Society
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• v.2 no.1
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• pp.3-7
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• 1973

Zellner, Kmenta, Dreze (1966) and later Hedges (1969) showed that consistent estimates of the parameters of Cobb-Douglas or CES production functions can be obtained by the single equation estimation methods if the models incorporate the assumption that firms maximize the mathematical expectation of profits. This note demonstrates that the results of the above-cited works can be extended to a class of VES production function models.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.19 no.4
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• pp.447-457
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• 2021

Graphite Isotope Ratio Method (GIRM) can be used to estimate plutonium production in a graphite-moderated reactor. This study presents verification results for the GIRM combined with a 3-D polynomial regression function to estimate cumulative plutonium production in a graphite-moderated reactor. Using the 3-D Monte-Carlo method, verification was done by comparing the cumulative plutonium production with the GIRM. The GIRM can estimate plutonium production for specific sampling points using a function that is based on an isotope ratio of impurity elements. In this study, the ¹⁰B/¹¹B isotope ratio was chosen and calculated for sampling points. Then, 3-D polynomial regression was used to derive a function that represents a whole core cumulative plutonium production map. To verify the accuracy of the GIRM with polynomial regression, the reference value of plutonium production was calculated using a Monte-Carlo code, MCS, up to 4250 days of depletion. Moreover, the amount of plutonium produced in certain axial layers and fuel pins at 1250, 2250, and 3250 days of depletion was obtained and used for additional verification. As a result, the difference in the total cumulative plutonium production based on the MCS and GIRM results was found below 3.1% with regard to the root mean square (RMS) error.

• The Journal of Fisheries Business Administration
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• v.25 no.2
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• pp.47-58
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• 1994

This paper tries to estimate cost and profit functions under Cobb - Douglas production technology in the coastal fishing, using duality theory of production technology and cost function. Therefore this paper estimates in advance the production functions with two input variables, the number of working persons per tonage(WEMP) and the number of fishing equipment per tonage(WEQU). Then this paper estimates profit function and implicit cost function using the estimated coefficients from production functions. The results of this study show that the annual average profit pertonage of long bag set fishing and trap fishing amount to 4.1 million won and 3.9 million won respectively.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.42 no.4
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• pp.145-152
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• 2019

All machines deteriorate in performance over time. The phenomenon that causes such performance degradation is called deterioration. Due to the deterioration, the process mean of the machine shifts, process variance increases due to the expansion of separate interval, and the failure rate of the machine increases. The maintenance model is a matter of determining the timing of preventive maintenance that minimizes the total cost per wear between the relation to the increasing production cost and the decreasing maintenance cost. The essential requirement of this model is that the preventive maintenance cost is less than the failure maintenance cost. In the process mean shift model, determining the resetting timing due to increasing production costs is the same as the maintenance model. In determining the timing of machine adjustments, there are two differences between the models. First, the process mean shift model excludes failure from the model. This model is limited to the period during the operation of the machine. Second, in the maintenance model, the production cost is set as a general function of the operating time. But in the process mean shift model, the production cost is set as a probability functions associated with the product. In the production system, the maintenance cost of the equipment and the production cost due to the non-confirming items and the quality loss cost are always occurring simultaneously. So it is reasonable that the failure and process mean shift should be dealt with at the same time in determining the maintenance time. This study proposes a model that integrates both of them. In order to reflect the actual production system more accurately, this integrated model includes the items of process variance function and the loss function according to wear level.

• Journal of Preventive Medicine and Public Health
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• v.24 no.3 s.35
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• pp.400-413
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• 1991

The purpose of this paper is to identify factors affecting the optimum mix of required inputs and other relevant factors which account for the variation in physician's productivity in general hospitals, and to find out their implications for the efficient health planning and management. An extended version of Cobb-Douglas production function and cross sectional data of one day patient census from all general hospitals in Korea in 1988 were used in the analysis. Main results of the analysis and their implications could be summarized as follows : (1) The production function for physician's inpatient service shows the evidence of economies of scale, but the production function for physician's outpatient and adjusted-patient service, which combines both out- and in-patient service, shows that of dis-economies of scale. (2) The physician's role for production for all service is smaller than auxiliary personnel's, which imply that more intensive utilization of nurses, nursing aides and other auxiliary personnel is desirable for improving general hospital productivity (3) In case of physician's inpatient and adjusted-patient service, nurses' role is greater than nursing aides'. Therefore, more extensive utilization of nurses is recommended for the efficient operation of general hospitals. (4) The factor of hospital beds plays the leading role among required inputs in the production for physician's in- and adjusted-patient service. (5) The physician's productivity of general hospitals in rural area is lower than that in urban area. And the productivity of teaching hospitals is lower than that of the other hospitals. Further analysis was made in physician production function based upon the size of hospitals, namely those hospitals below 250 beds and those above. Explained variances by the factor of hospital beds was significantly increased in the case of those hospitals above 250. A more detailed and thorough investigation is needed for verifying factors influencing physician's productivity in general hospitals in Korea.

• Proceedings of the KOSOMBE Conference
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• v.1993 no.11
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• pp.171-174
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• 1993

We propose the vocal tract area function as the feature vector of speech recognition. Vocal tract area function is directly related to speech production. The vocal tract area function is not only showing mechanism of speech production but also can be used as an effective feature vector in speech, recognition in this study.

• The Journal of Fisheries Business Administration
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• v.23 no.2
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• pp.91-99
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• 1992

It has been one of the critical issues that the researchers properly evaluate the fishing rights foregone by the coastal development activities like wetland reclamation. Particularly, estimating the productivity of concerned fishing rights is known to play a significant role in their monetary compensation. As a result, this paper attempts to develop a statistical model characterized by Cobb-Douglas production function in conjunction with the fisheries' productivity estimation. The primary hypotheses involving their statistical production function are as below : 1. The quantity of fisheries production is hypothesized to be expressed as a function of capital (K) and labor(L) put into fishing activities. 2. The estimated parameters of K and L are hypothesized to satisfy the conventional condition of production function as a form of Cobb-Douglas. These statistical tests reveal that the shellfish farming productivity heavily depends on the acre of mariculture while the input of labor force also considerably affects its productivity. In case of the fixed net fishing productivity, both the factors of capital and labor similarly affect the marginal change in its productivity. En addition, the productivity of shellfish (arming turns out to follow the increasing returns to scale, whereas that of fixed net fishing comes up with the decreasing returns to scale.

• The Journal of Fisheries Business Administration
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• v.26 no.1
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• pp.9-27
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• 1995

From now on, the direction of fishery products circulation measure should be improved the system to give just the right of free choice of sale route like retail, direct sale, direct dealings and direct shipping only for fishermen to produce them diversifing the function and the role of current fish market in the production to prepare the fishery internationalization, to improve the competitiveness of coastal and off-shore fishery. Practically wholesale market in land and fish market in the production have the different function and role, the organization of wholesale market in land can't substitute the essential function and role which fish market in the production should perform. So far, fisheries cooperatives as a managing subject of fish market in the production have depended on the consignment sales and purchases of fishery products but, from now on, it should be explore the widespread supply way of fishery products by producing value - added fishery products that should bring higher demand from the consumers, producer - consumer direct marketing system through not only consignment sales but also direct sales that common processing and manufacturing system of fishery products under the management of FC has been established. The direction of the idealest structural improvement of fishery production circulation organization is to establish the the position of the fishery retail price leader based on the standard of market in the fisheries production due to existing characteristics of fisheries, accordingly, to harmony the market organization of direct transportation, direct sales and direct dealings form by producer and group of producers with market organization in the fisheries production, and to make the condition to do the appropriate distributive function.

• Information Systems Review
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• v.2 no.1
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• pp.151-160
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• 2000