• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.361-363
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• 2011

This paper proposes a method for choosing the best transmission system expansion(TEP) plan considering an annual outage cost and a probabilistic transmission system reliability criterion ($_RLOLE_{TS}$). The objective method minimizes a total cost which are an investment budget for constructing new transmission lines and an annual outage cost, subject to the probabilistic transmission system reliability criterion, which consider the uncertainties of power system facilities. Test results on an existing 21-bus system are included in the paper. It demonstrated the suitability of the proposed method for solving the transmission system expansion planning problem subject to practical future uncertainties.

• Journal of Korean Institute of Industrial Engineers
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• v.17 no.1
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• pp.51-58
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• 1991

This paper presents a single-echelon, single item, stochastic lead time and static demand inventory model for situations in which, during the stockout period, a fraction ${\beta}$ of the demand is backordered and the remaining fraction $(1-{\beta})$ is lost. In this situations, an objective function representing the average annual cost of inventory system is obtained by defining a time-proportional backorder cost and a fixed penalty cost per unit lost. The optimal operating policy variables minimizing the average annual cost are calculated iteratively. At the extremet ${\beta}=1$, the model presented reduces to the usual backorder case. A numerical example is solved to illustrate the algorithm developed.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.1
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• pp.21-28
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• 2013

The paper proposes an optimal sizing method of a customer's battery energy storage system (BESS) which aims at managing the electricity demand of the customer to minimize electricity cost under the time of use(TOU) pricing. Peak load limit of the customer and charging and discharging schedules of the BESS are optimized on annual basis to minimize annual electricity cost, which consists of peak load related basic cost and actual usage cost. The optimal scheduling is used to assess the maximum cost savings for all sets of candidate capacities of BESS. An optimal size of BESS is determined from the cost saving curves via capacity of BESS. Case study uses real data from an apartment-type factory customer and shows how the proposed method can be employed to optimally design the size of BESS for customer demand management.

• The Journal of the Convergence on Culture Technology
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• v.5 no.4
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• pp.137-145
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• 2019

Among the participants of the 2012 Korea Medical Panel survey, 308 people who have used emergency, hospitalization and outpatient services for cancer have been selected. The average annual direct cost per cancer patient was analyzed by adding up the patient's medical expenses, industrial copayments, and non-salary costs. The average annual direct direct cost of cancer spent by cancer patients is about 129,093,792 per male, 158,100,612 won for men and 110,482,075 for women.For those with health insurance, the total direct cost per person from cancer was 183,095,125 won and the beneficiaries were 46,241,705 won. By household income, the average annual direct direct costs per person were 112,459,971 won per patient in the household income quartile, 137,910,890 won for patients in the second quartile, 149,556,570 won in the third quartile and 112,730,461 won, quartile 5, respectively.Was 142,926,331 won.

• The Journal of the Korea Contents Association
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• v.15 no.6
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• pp.43-53
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• 2015

This study analyzes economic feasibility of the LED lighting system compare to the halogen. To evaluate economic feasibility of the LED devices, we analyzed the size of theater, current value of the lighting devices in kinds, annual cost and annual cost according to the surface in case of designing stage lighting system with LED using WEELS 2011. Also, to compare energy consumption, we analyzed consumption and amount of electric energy by the surface and the amount of CO2 emission. Data showed that annual cost of the LED devices are highly inexpensive than halogen and now the value is of great. However initial cost of the equipment 200% higher than halogen. Though LED devices are expensive in startup setting, the value of utilization factor is large and depreciation years of LED(30years) are longer than halogen(2years). Therefore, annual cost of LED can make up the minus. Consider the tendency of reducing price of LED devices, we can assume that annual cost of the LED will be lower than halogen devices. Further, in 3years the expense of LED and halogen is reversed.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.6
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• pp.1046-1052
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• 2010

In residential house, photovoltaic (PV) system among various alternatives in renewable energy system is the most efficient and feasible solution for reducing energy consumption and electricity cost. However, relatively high initial cost make people reluctant to install PV system in their houses. Therefore, in the initial state for PV system installation in the house, it is very important to decide proper capacity of the PV system considering the expected energy usage and solar energy supplying condition with the house. This paper proposes a novel optimization model for deciding appropriate capacity of the PV system for residential house. The objective function of the model is to minimize the annual cost including electricity bill, operation and maintenance cost, and annual fixed cost calculated from the initial installation cost based on capital recovery factor (CRF). The model also shows the optimal inclining angle of PV panels of the system. In this paper, we estimate the PV output using PVWATTS (PV simulator of Office of Energy Efficiency and Renewable Energy) and find optimal solutions by Sequential Quadratic Programming (SQP) method using MATLAB software. The proposed approach is finally applied to a residential model house in Gangneung, Gangwon-Do and verified its feasibility for adopting to PV system design for residential houses.

• Proceedings of the KIEE Conference
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• 2006.11a
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• pp.275-278
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• 2006

This paper describes a probabilistic annual congestion cost assessment of a grid at a composite power system derived from a model. This probabilistic congestion cost assessment simulation model includes capacity limitation and uncertainties of the generators and transmission lines. In this paper, the proposed probabilistic congestion cost assessment model is focused on an annualized simulation methodology for solving long-term grid expansion planning issues. It emphasizes the questions of "how should the uncertainties of system elements (generators, lines and transformers, etc.) be considered for annual congestion cost assessment from the macro economic view point"? This simulation methodology comes essentially from a probabilistic production cost simulation model of composite power systems. This type of model comes from a nodal equivalent load duration curve based on a new effective load model at load points. The characteristics and effectiveness of this new simulation model are illustrated by several case studies of a test system.

• Korean Chemical Engineering Research
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• v.59 no.3
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• pp.467-479
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• 2021

Abstract: A kinetic model was developed for the dehydration of ethanol to ethylene based on two parallel reaction pathways. Kinetic parameters were estimated by fitting experimental data of powder catalysts in a lab-scale test, and the effectiveness factor was determined using data from pellet-type catalysts in bench-scale experiments. The developed model was used to design a multitubular fixed-bed reactor (MTR) and an adiabatic reactor (AR) at a 10 ton per day scale. The two different reactor types resulted in different process configurations: the MTR consumed the ethanol completely and did not produce the reaction intermediate, diethyl ether (DEE), resulting in simple separation trains at the expense of high equipment cost for the reactor, whereas the AR required azeotropic distillation and cryogenic distillation to recycle the unreacted ethanol and to separate the undesired DEE, respectively. Quantitative analysis based on the equipment and annual energy costs showed that, despite high equipment cost of the reactor, the MTR process had the advantages of high productivity and simple separation trains, whereas the use of additional separation trains in the AR process increased both the total equipment cost and the annual energy cost per unit production rate.

• Journal of Acupuncture Research
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• v.33 no.2
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• pp.61-76
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• 2016

Objectives : This study was designed to clarify population-social characteristics that influence the utilization patterns of hospitalized patients in a traditional korean hospital, thereby providing clinical data which would help further improvements of traditional korean medical service in particular the Acupuncture and Moxibustion. Methods : We investigated population-social characteristics and annual utilization patterns of all patients who were hospitalized for more than 24 hours in a Korean Medical Hospital from January 2005 to December 2014. The obtained data were recorded in the EMR chart and statistical analysis was performed using SPSS 21.0. Additionally, data from the patients admitted to the department of Acupuncture and Moxibustion were analyzed separately. Results : 1. All inpatients had a significant annual difference in age, gender, hospitalized department, and disease code annually but not in re-hospitalization number. Inpatients of the department of Acupuncture and Moxibustion also varied in their age, gender, and disease code annually, but not in re-hospitalization number. 2. Pearson correlation analysis on all inpatients showed that the mean days of hospital treatments had a negative correlation with all variables except medical care insurance. Total cost, cost per day per person and recuperation cost had a positive correlation with all variables except medical care insurance. There was no meaningful relationship between nonrecuperation cost and the variables. 3. Stepwise multiple regression analysis on all inpatients showed that the mean days of hospital treatments had a negative correlation with all variables except automobile insurance. The total hospitalization costs had a positive correlation with both general insurance and medical care insurance. Cost per day per person and recuperation cost had a positive correlation with the females. There was no meaningful relationship between non-recuperation cost and the variables. 4. Pearson correlation analysis on inpatients of the department of Acupuncture and Moxibustion inpatients showed that the mean days of hospital treatments had a positive correlation with all variables except general insurance and automobile insurance. Total cost and recuperation cost had a positive correlation with all variables except medical care insurance, and cost per day per person had a positive correlation with females and general insurance. There was no meaningful relationship between non-recuperation cost and the variables. 5. Stepwise multiple regression analysis on inpatients of the department of Acupuncture and Moxibustion inpatients, the mean days of hospital treatments, total cost, cost per day per person and recuperation cost had a positive correlation with general insurance. There was no meaningful relationship between non-recuperation cost and the variables. Conclusion : Population-social characteristics of inpatients annually varies, and the change influences the utilization pattern.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2007.12a
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• pp.241-242
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• 2007

This paper aims to determination of container ship's economical replacement policy by Fuzzy Annual Equivalent Cost Method Especially, though there was much vagueness to expense for calculation of container ship's economical life, this paper expressed such vague nature with a fuzzy number. And this paper developed the fuzzy expense model with a fuzzy number, and to analyze more practically than an expense model, was decided economical life-age with an application in a containership of various volumes.