• 대한전기학회논문지
• /
• 제43권2호
• /
• pp.197-205
• /
• 1994

Security of a power system refers to its robustness relative to a set of imminent disturbances (contingencies) during operation. The socially optimal solution for the actuall level of generation/consumption has been well-known spot pricing at shot-run marginal cost. The main disadvantage of this approach arises because serious contingencies occur quite infrequently. Thus by establishing contractual obligations for contingency offering before an actual operation time through decision feedback we can obtain socially optimal level of system security. Under probabilistic precontract pricing the operating point is established at equal incremental cost of the expected short-run and collapse cost of each participant. Rates for power generation/consumption and for an offer to use during a contingency, as well as information on the probability distribution of contingency need for each participant, are derived so that individual optimization will lead to the socially optimal solution in which system security is optimized and the aggregate benefit is maxmized.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2008년도 제39회 하계학술대회
• /
• pp.424-425
• /
• 2008

This paper presents application of RCM(Reliability Centered Maintenance) in waterworks system. The reliability-based probability model for predicting the failure probability is established and FTA(Fault Tree Analysis) is proposed to considering RCM. To calculate failure probability, Weibull distribution is usually used due to age related reliability. FTA is an engineering analysis which is using logic symbols. The real historical data of CMMS(Computerized Maintenance Management System) make full use of case study for waterworks system. Consequently, the RCM would be likely to permit utilities to reduce overall costs in maintenance and improve the total benefit.

• 무역상무연구
• /
• 제20권
• /
• pp.181-212
• /
• 2003

Many seafood processing and export companies are scattered in Pusan area. Most of them has experienced hardships, because of physical distribution and sanitary costs, rent costs and Non-tariff barriers. GamCheon One-Stop Seafood Export Complex (GOSEC) is considered as the project which is necessary to establish GamCheon port as the seafood trade hub of Northeast Asia. GOSEC is to build the processing and export complex for seafood export. It applies to small and medium seafood export company. This paper aims to examine the economic benefit which could be derived from the construction of GOSEC. It reviews the quantifiable benefits of companies which wants to move into GOSEC. It also shows the results of questionnaire carried out to find the characteristics of potential GOSEC tenants.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2003년도 통신소사이어티 추계학술대회논문집
• /
• pp.3-6
• /
• 2003

Crosstalk among telephone lines in the same bundles is a major impairment in current VDSL systems. In this paper, we analysis the crosstalk effect of DSL using different frequency band upon ANSI standard VDSL systems. Simulation results show that data rate of ANSI VDSL decrease by crosstalk from another VDSL using different frequency. This study has the potential implication and benefit for ANSI standard DMT VDSL energy distribution in subchannel

• 한국조경학회지
• /
• 제23권3호
• /
• pp.94-105
• /
• 1995

Purposes of this study were to apply and examine that the importance-performance analysis(IPA) could be a useful park management tool. The IPA is an easily-applied technique developed in marketing field to measure attribute importance and performance. It displays them simultaneously on a 4-quardrant action grid; therefore, park managers can upgrade current services and address marketing strategies for various user segments. The children's grand park was selected as a study are. Two different types of questionaires were utilized for data analyses. They were collected from one respondent by on-site distribution or by mail survey, because attribute importance and performance should be rated before and after visiting a park, respectively. Then, total data was segmented systematically by 2 variables-age and benefit sought. Action grids from order to meet the needs of each segment. Several comments on both data collection methods and segment variables selection were described to improve the IPA in recreation settings for future researches.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2003년도 추계학술대회 논문집 전력기술부문
• /
• pp.151-153
• /
• 2003

This paper proposes determining a optimal number, size and allocation of DGs(Distributed Generations) needed to minimize operation cost of distribution system, obtains economic benefit in operation planning of DG and improves system reliability. System reliability is assessed whether DG install and reliability cost consider. DG optimal allocations are determined to minimize total cost with power buying cost, operation cost of DG, loss cost and outage cost using GA(Genetic Algorithm). And it was determined installed load-point and order.

• 기술사
• /
• 제41권2호
• /
• pp.45-50
• /
• 2008

At this point, the Pan-Korea Grand Waterway (PKGW) has negative views and various complicated problems, but the government chose PKGW as important project for having a benefit in physical distribution, tourism, aggregate sale and new employment as well as in view of disaster prevention, flood control, irrigation. The government makes special laws for PKGW in evaluating environment effect and the safety of existing facilities and considers countermeasures for the rehabilitation, movement and redevelopment of facilities by related company and specialist. From analyzing and investigating the collective results in detail and in stages, the PKGW is the best choice by which korea engineers can hand over pleasant and beautiful korea to next generation in world.

• Nuclear Engineering and Technology
• /
• 제54권6호
• /
• pp.2321-2328
• /
• 2022

The passive safety system is adopted in an AP1000 nuclear power unit to improve the operation safety of the whole unit. However, due to boron diffusion and periodic sampling, boron dilution occurs in the core makeup tank. The boron replenishment process in the core makeup tank is essential and becomes particularly important. Based on the validated models, this article numerically investigates the influence of the replenishment flow rate and the position on the boron distribution in the core makeup tank. The thermal fatigue phenomenon of the "T" connection caused by replenishment is analyzed. Finally, the replenishment strategy is proposed to benefit both boron mixing in the core makeup tank and eliminating the thermal fatigue of the "T" connection.

• 보건행정학회지
• /
• 제19권2호
• /
• pp.36-50
• /
• 2009

Korean Government had performed three pilot programs to introduce the long term care insurance system. Persons aged 65 or older who are dependent on others for daily living could use long term care services in the pilot program. The long-term care insurance covered nursing home services, home care services and cash benefits. The cash benefits are included that for elderly at home and for patients in geriatric hospital. This study investigated whether there had been any change in the medical care utilization according to cash benefits for geriatric hospitalization. This study used National Health Insurance claims and Long term Care Insurance claims 2003 through 2006. Data were composed of subjects who undertook both insurance coverage. The subjects was divided into two groups. Case group included participants with the cash benefits of geriatric hospitalization. Control group included persons without the cash benefits selected by random sampling according to the distribution of case group. This study showed that the amount of medical care utilization of the case group is more significantly increased than the control group after adjusted their health condition and functional condition. This result will be helpful for making decisions on whether the cash benefit of geriatric hospitalization can be introduced into long term care insurance system.

• 한국지리정보학회지
• /
• 제11권1호
• /
• pp.138-154
• /
• 2008

1996년부터 3단계 국가GIS 5개년 계획이 시행되고 있는 현재까지 지리정보기술은 다양한 분야에 활용되고 있으나, 그 기술의 근간이 되는 지리공간자료의 최신성과 정확성을 확보할 수 있는 체계를 갖추지 못하고 있다. 지리공간자료(수치지형도, 수치주제도)와 관련된 업무는 지형지물의 변화 발생에서 부터 자료수집, DB 구축, 유통, 공유 등 모두가 개별적으로 이루어지고 있다. 이와 같은 개별구조를 하나의 흐름으로 연계하여 효율적이고 체계적인 업무처리가 이루어질 수 있도록 일관성 있는 모형개발이 요구되고 있다. 본 연구에서는 대구광역시를 사례로 지리공간자료의 경제적 갱신과 교환 방안을 제시하고, 기존의 업무수행 절차와 비교하여 비용편익분석을 실시하였으며, 그 결과를 이용하여 모형을 개발하였다.