• Proceedings of the Korean Operations and Management Science Society Conference
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• 2001.10a
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• pp.209-212
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• 2001

To have competitive advantage over competing telecommunications services, it is crucial to provide higher value with lower cost. In this study, CUP (Cost-Utility-Preference) chart is developed to analyze the market competition dynamically. It considers both the competition and customers' preference of each service to explain the change of the competitive landscape over time. Conjoint analysis is used for detailed analysis. Using the chart, we can analyze the currently competing services, predict the future scenarios of the competition, develop new services, and understand the causes of successes or failures of telecommunications services.

• Management Science and Financial Engineering
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• v.7 no.2
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• pp.13-30
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• 2001

This paper discusses a paradox in an Indefinite Quadratic transportation Problem. Here, the objective function is the product of two linear functions. A paradox arises when the transportation problem admits of a total cost which is lower than the optimum cost, by transporting larger quantities of goods over the same route. A sufficient condition for the existence of a paradox is established. Paradoxical Range of flow is obtained for any given flow in which the corresponding objective function value is less than the optimum value of the given transportation problem. It is illustrated with the help of a numerical example.

• Korean Management Science Review
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• v.21 no.3
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• pp.1-12
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• 2004

The paper demonstrates that versioning of digital products occurs more frequently than that of physical products because of low marginal cost. The versioning occurs no matter what a customer knows his/her reservation price. Low-quality version will not be produced when the difference between reservation prices is very large. The paper also shows that a firm tries to lower the quality of low-quality product to prevent customers with high reservation prices from purchasing low-quality product.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1366-1369
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• 2003

Today, the industries use polymer material for many purpose. Specially, it is important in automobile industry because tile costs of polymer hold high proportion of the overall cost. If we reduce the weight of automobile, fuel efficiency of car is raised and cost of bumper is lower. Therefore there are many efforts to reduce of car currently. The purpose of this paper is to reduce polymer used in car bumper.

• Journal of the Korean Institute of Telematics and Electronics
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• v.9 no.3
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• pp.17-21
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• 1972

There are two kinds of tile dial Keyserider which is used in recently, one is a electromechanical relay type, the other is a mechanical type. It is, however, that above types are very high cost to manufacture. therefore it is desinged a new type by using the transistor switching circuit so that it is small size and can be manufactured lower cost than other types.

• Journal of Wetlands Research
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• v.19 no.2
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• pp.211-215
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• 2017

The market of the municipal wasetewater treatment plant (MWTP) operation is expanding across the world including Korea. The contracting-out system was introduced for the effective operation of MWTPs. However, an improvement of the contracting-out system of MWTP has been continuously required. This research investigated current operational status of MWTPs in Korea, to suggest the improvement of the cost effective MWTP operation to promote the contracting-out system of MWTP operation. Results showed that lower operational costs of MWTP were lower in larger MWTPs than in smaller MWTPs. Overall, MWTPs operated by a public enterprise showed lower operational costs than those operated by government agencies and private enterprises. Among the MWTPs similar in their treatment capacity, treatment process and operation period, MWTPs operated by private enterprises showed the lowest operational cost. According to the survey, managers and operators of MWTPs emphasized the importance of improvement on the methods of selecting operating agencies and estimating operationing costs. The results of this study should be useful as important supporting data to promote the contracting-out system for the MWTP operation.

• Journal of Korean Academy of Nursing Administration
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• v.4 no.2
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• pp.351-361
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• 1998

The purpose of this study was to explore whether there is a point within the range of physical impairment after which the cost of home care exceeds the cost of nursing home care among the elderly who require long-term care. The provision of long-term care for the elderly is a major health policy issue, in part due to the aging of the American population and dramatic increase in health care costs. The framework for this study was guided by Pollak's(1973)model of costs of alternative care settings for the elderly. This study used a retrospective, descriptive correlational design. Physical impairment was measured by the modified Index of Activities of Daily Living(Katz et al. 1963). Cost of care was measured by the average cost per patient per day. The sample for this study included 67 patients receiving long-term care at home from the Long-term Home Health Care Programs (LTHHCPs) and 67 patients receiving long-term care in nursing homes. Data were collected on patient characteristics. including activities of daily living and cognitive impairment. and on the number of physician visits. emergency room visits. and hospitalization from the patient records. For each patient. Medicaid cost data for home care services/or nursing home services were collected from the financial department of each home care agency or nursing home. The living costs and informal care costs were estimated for home care patients. The results indicated that the home care sample and the nursing home sample were similar in terms of gender. ethnic background. and marital status. The elderly patients in the home care sample were: however. younger and less physically impaired than those in the nursing home sample. The hypotheses of this study were supported: For elderly persons with physical impairment scores below 12(possible range of 0 to 14), cost of care was lower in home care than in the nursing home care setting. However, for elderly persons with physical impairment scores above 12. the cost of care was higher in home care than in the nursing home care setting. Thus. in this sample for elderly patients with extreme physical impairment, the cost of home care exceeded the cost of nursing home care.

• Journal of Biosystems Engineering
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• v.7 no.1
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• pp.42-52
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• 1982

This study was intended to develop a cost function for the natural air in-bin drying: system which could lead to an optimization of the drying system cost. Based on the cost function developed, a series of simulated drying tests were conducted with 10-year weather data (1970~1979) for 7 different regions by applying an appropriate levels of system factors. System performance factors treated in this study were initial moisture content, airflow rate, bin diameter and grain depth. An optimization procedure to find the least cost system was developed as follows: First, the worst year of the past decade was determined in consideration of the dryiang time and maximum dry matter loss. Second, the minimum airflow rate for a fixed bin diameter and grain depth was determined. Third, the optimum grain depth was found for the minimum airflow rate with different initial moisture contents and bin diameters. The results obtained in this study are summarized as follows: 1. The optimization procedure developed in this study was able to reduce the time and efforts significantly. 2. Optimum values of drying parameters including airflow rate, grain depth, and fan size were determined for different initial moisture contents and bin diameters in each region. The results are shown in Tables 3 to 9. 3. Optimum grain depths decreased as the initial moisture content and airflow rate increased. 4. Drying time for the least cost system should be reduced with higher initial moisture content and lower drying potential to prevent grain spoilage. 5. The fixed cost was 65 to 75 percent of the total system cost and the variable cost was 25 to 35 percent. To reduce the fixed cost it is desirable to use a drying bin 2 or 3 times a year.

• The Journal of the Korea Contents Association
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• v.18 no.9
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• pp.209-216
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• 2018

This study examines the impact of corporate social responsibility activities (CSR) on cost stickiness. The asymmetrical cost behavior in which the cost reduction rate of a company is lower than the cost increase rate of an increase in sales is called cost stickiness. In this study, we separated the companies with CSR and those without CSR, and then compared their cost behaviors. This study reports that the cost stickiness of the companies performing the CSR is stronger than the companies that did not. This means that the company needs ongoing investments to create value through the CSR, so it is difficult to reduce committed resources involved immediately when sales declines. We expect that the result of this study provides meaningful insight to participants in the capital market by presenting empirical evidence that the firms' CSR can affect the managers' costs decisions.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.43 no.3
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• pp.95-100
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• 2020

Machines and facilities are physically or chemically degenerated by continuous usage. One of the results of this degeneration is the process mean shift. The representative type of the degeneration is wear of tool or machine. According to the increasing wear level, non-conforming products cost and quality loss cost are increasing simultaneously. Therefore a periodic preventive resetting the process is necessary. The total cost consists of three items: adjustment cost (or replacement cost), non-conforming cost due to product out of upper or lower limit specification, and quality loss cost due to difference from the process target value and the product characteristic value among the conforming products. In this case, the problem of determining the adjustment period or wear limit that minimizes the total cost is called the 'process mean shift' problem. It is assumed that both specifications are set and the wear level can be observed directly. In this study, we propose a new model integrating the quality loss cost, process variance, and production volume, which has been conducted in different fields in previous studies. In particular, for the change in production volume according to the increasing in wear level, we propose a generalized production quantity function g(w). This function can be applied to most processes and we fitted the g(w) to the model. The objective equation of this model is the total cost per unit wear, and the determining variables are the wear limit and initial process setting position that minimize the objective equation.