• Journal of Electrical Engineering and Technology
• /
• 제2권2호
• /
• pp.201-207
• /
• 2007

As the power industry moves towards open competition, there has been a need for methodology to evaluate distribution power system reliability by using customer interruption costs, particularly in power supply zones under the competitive electricity market. This paper presents an algorithm to evaluate system average interruption duration index, expected energy not supplied, and system outage cost taking into consideration failure rate of the distribution facility and industrial customer interruption cost. Also, to apply this algorithm to evaluate system outage cost presented in this paper, the distribution arrangement of a dual supply system consisting of mostly high voltage customers in an industrial complex in Korea is used as a sample case study. Finally, evaluation results of system interruption cost, system average interruption duration index, and expected energy not supplied in the sample industrial complex area are shown in detail.

• 한국임상약학회지
• /
• 제20권3호
• /
• pp.278-287
• /
• 2010

The main objective of this study is to evaluate the cost-effectiveness of tafluprost compared with latanoprost in primry open Angle Glaucoma (POAG) or ocular hypertension OH patients in Korea. A decision analytic model was developed from a societal perspective to estimate clinical outcome, drug cost and glaucoma related cost. The model assumes branch like following: successful treatment, switching to other drug, adding other drug, laser or surgery. Treatment success rate is defined as the percentage of patients with elevated IOP achieving <20% reduction, and discontinuation rate is the percentage of patients who were withdrawn due to severe adverse events. A model that is comprised of 1 month cycle length has 1 year. Treatment success rate and discontinuation rate were obtained from published literatures searched in database. Resource utilizations and costs were calculated with national health insurance data and clinical expert opinions. Sensitivity analyses were performed on crucial parameters. Tafluprost is less costly than latanoprost, $609.0 vs $651.2 expected cost. Thus tafluprost was shown to be dominant compared with latanoprost. The results of sensitivity analysis revealed stable across most of the included parameters. According to this study, tafluprost shows more clinical outcome for 1 year than latanoprost. In addition, first-line treatment of tafluprost is a more cost-minimizing strategy associated with POAG or OH compared with latanoprost.

• 한국전문물리치료학회지
• /
• 제9권1호
• /
• pp.43-51
• /
• 2002

Physiological Cost Index (PCI) of walking has been widely used to predict oxygen consumption in healthy subjects or patients. The purpose of this study was to evaluate the predictability of physiological cost index of walking for the amount of exercise and cardiac function. Walking exercise was conducted in 67 healthy children (age 4-12) with a self-selected comfortable walking speed on the level surface. Walking speed was calculated, and heart rate was measured before and immediately after the walking. PCI was calculated for statistical analysis. The results were as follows; 1) The walking speed tends to increase and PCI of walking tends to decrease with age. There was significant difference in walking speed and PCI of walking among three age groups (p<.05). The change of walking heart rate tends to decrease with age, however, there was no significant difference among three age groups. 2) Linear regression equation between walking speed and age was 'Y (walking speed) = 2.124X (age) + 48.286' ($R^2$=.337), (p=.00). 3) The walking heart rate tends to decrease with age. Linear regression equation between walking heart rate and age was 'Y (walking heart rate) = 143.346 - 2.63X (age)' ($R^2$=.3425), (p=.00). 4) The walking heart rate decreased as body surface area (BSA) increased. Linear regression equation between walking heart rate and BSA was 'Y (walking heart rate) = 149.830 - 27.115X (BSA)' ($R^2$=.3066), (p=.00). In conclusion, these equations and PCI could be useful to quantify the variation of energy expenditure of children with pathological gait when compared with age-matched healthy children.

• Journal of applied mathematics & informatics
• /
• 제12권1_2호
• /
• pp.251-260
• /
• 2003

Generally, in deriving the solution of economic production quantity (EPQ) inventory model, we consider the demand rate and deterioration rate as constant quantity. But in case of real life problems, the demand rate and deterioration rate are not actually constant but slightly disturbed from their original crisp value. The motivation of this paper is to consider a more realistic EPQ inventory model with finite production rate, fuzzy demand rate and fuzzy deterioration rate. The effect of the loss in production quantity due to faulty/old machine have also been taken into consideration. The methodology to obtain the optimum value of the fuzzy total cost is derived and a numerical example is used to illustrate the computation procedure. A sensitivity analysis is also carried out to get the sensitiveness of the tolarance of different input parameters.

• 보건행정학회지
• /
• 제17권1호
• /
• pp.1-27
• /
• 2007

This study is designed to estimate an appropriate level of patient's cost-sharing for oriental medical services in the Korean National Health Insurance. The findings of this study can be summarized as follows: 1) The current co-payment system for oriental medical services does not reflect its cost structure in clinical practice due to inconsistency of cost-sharing plan in the NHI. 2) Both oriental medical institutions and their patients, as a result, are at a relative disadvantage in financial burden, compared with other services. 3) The substantial proportion of patients' cost-sharing depends on the amount of co-payment and the range of medical cost that a flat rate is applied to. 4) The extension of the range doesn't make any substantial decrease in patient's cost-sharing. 5) The fixed amount of co-payment is more sensitive than a range to total variations of patient's cost-sharing. Based on the above, the budget impacts of a new co-payment system were estimated for each co-insurance rate, according to given scenarios. The results range from -59 billion Won (-8.5%) to 16 billion Won(2.3%).

• 대한산업공학회지
• /
• 제33권1호
• /
• pp.70-75
• /
• 2007

This paper discusses condition based preventive replacement for deteriorating systems. The system continuouslydeteriorates in time and fails at any deterioration level which is always monitored, It is replaced at failure or atsome deteriorated level preventively before failure. The deterioration process is represented by a Weibulldistribution with a time-linear scale parameter. The cost rate function is formed considering replacement costand opportunity loss cost and deterioration dependent failure distribution, If the system has an increasingdeterioration dependent failure rate, the optimal deterioration level for preventive replacement can be determinedfrom minimizing the cost rate. An illustrative example is given for a Weibull deterioration dependent failuredistribution.

• 수산해양교육연구
• /
• 제27권4호
• /
• pp.1092-1098
• /
• 2015

Fishing population has been increasing with national income improvement and the five-day workweek in Korea. Recently commercial fishing facilities like pay fishing pond are emerging as demand of saltwater fishing increases, unlike the past when inland fishing was prominent. In order to do businesses, economic analysis should be done in advance. This study aimed to make an Economic analysis of Uljin pay-fishing place by estimating the cost and benefit, and calculating the rate of economic return. The results show the Uljin pay-fishing place's net present value of 3.5 billion won, internal rate of return of 14%, and benefit cost ratio of 1.16 at 5.5% social discount rate.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2017년도 추계 학술논문 발표대회
• /
• pp.205-206
• /
• 2017

The purpose of this paper is to examine a reasonable share of cost in the apartment remodeling projects. Therefore, the case model of remodeling apartment was made up and then the rate of return by method of floor area change rate, method of proportion, method of investment earnings rate and method of proportion reflected business contribution were estimated. Consequently, the model by the method of proportion reflected business contribution presented 20.6% of rate in all apartment units.

• Smart Structures and Systems
• /
• 제22권2호
• /
• pp.151-159
• /
• 2018

Maintenance activities are regarded as a key part of the repairable deteriorating system because they maintain the equipment in good condition. In practice, many maintenance policies are used in engineering fields to reduce unexpected failures and slow down the deterioration of the system. However, in traditional maintenance policies, maintenance activities have often been assumed to be performed at the same time interval, which may result in higher operational costs and more system failures. Thus, this study presents two non-periodic preventive maintenance (PM) policies for repairable deteriorating systems, employing the failure rate of the system as a conditional variable. In the proposed PM models, the failure rate of the system was restored via the failure rate reduction factors after imperfect PM activities. Operational costs were also considered, which increased along with the operating time of the system and the frequency of PM activities to reflect the deterioration process of the system. A numerical example was provided to illustrate the proposed PM policy. The results showed that PM activities performed at a low failure rate threshold slowed down the degradation of the system and thus extended the system lifetime. Moreover, when the operational cost was considered in the proposed maintenance scheme, the system replacement was more cost-effective than frequent PM activities in the severely degraded system.

• 한국안전학회지
• /
• 제33권5호
• /
• pp.84-91
• /
• 2018

Despite the government 's efforts to reduce constructional disasters, it has been pointed out that the safety management cost of the Construction Technology Promotion Act does not reflect the actual site. Therefore, it is necessary to study the proper guideline of the safety management cost which can be used as the most fundamental measure to prevent construction accidents. Moreover for the securement of the reasonable safety management costs, it is important to calculate its appropriate rate. Thus, in this study, the appropriate rate of safety management cost was proposed by the construction cost & type based on the 111 execution plans of safety management cost, and the rate is analyzed to be 1/10 of the occupational safety and health management cost. The results of this study will be a guideline in improvement to the proper schedule rating system improvement and in implement of pilot projects.