• Communications for Statistical Applications and Methods
• /
• 제16권4호
• /
• pp.557-572
• /
• 2009

공무원연금제도가 도입된 지 40여 년이 지난 현재, 기대여명의 증가로 인해 수급자가 크게 늘어나 부양률이 상승하면서 공무원연금 재정이 문제가 되고 있다. 본 논문에서는 현재 공무원연금제도와 노령화 수준을 반영한 확률모형을 설정하여 개인가입자의 혜택수준을 검토하며, 연금재정의 안정성을 모의실험 하였다. 연구방법으로는 개인가입자별 총기여금과 총수령금의 기대값을 비교하는 방법과 몬테카를로 모의시행을 통해 기금의 파산확률 및 준비금, 국가보전금을 구해보는 방법을 이용하였다.

• Earthquakes and Structures
• /
• 제21권5호
• /
• pp.505-514
• /
• 2021

A formulation based on structural reliability and cost effectiveness is proposed to provide recommendations to select the best retrofit strategy for schools with reinforced concrete frames and masonry walls, among three proposed alternatives. The cost calculation includes the retrofit cost and the expected costs of failure consequences. Also, the uncertainty of the seismic hazard is considered for each school site. The formulation identifies the potential failure modes, among shear and bending forces for beams, and flexure-compression forces for columns, for each school, and the seismic damages suffered by the schools after the earthquake of September 17, 2017 are taken into account to calibrate the damaged conditions per school. The school safety level is measured through its global failure probability, instead of only the local failure probability. The proposed retrofit alternatives are appraised in terms of the cost/benefit balance under future earthquakes, for the respective site seismic hazard, as opposed to the current practice of just restoring the structure original resistance. The best retrofit is the one that corresponds to the minimum value of the expected life cycle cost. The study, with further developments, may be used to develop general recommendations to retrofit schools located at seismic zones.

• 한국수자원학회논문집
• /
• 제55권6호
• /
• pp.405-419
• /
• 2022

홍수피해를 최소화하기 위한 수공구조물의 적정 규모 결정을 위해 사용되는 홍수빈도분석에는 통계적 분석절차에 따른 불확실성이 포함된다. 따라서 불확실성이 포함된 범주 내에서 가장 적절한 설계홍수량(design flood)을 결정하는 과정은 수공구조물의 최종단계에서 중요하게 다루어져야 하는 부분이나 이를 제시한 연구는 많지 않다. 비용-편익 분석기법을 홍수빈도분석 절차에 도입하여 구성되는 총 기대비용함수(total expected cost function)는 설계홍수량 중 최적설계홍수량(optimal design flood)을 결정하기 위한 새로운 접근방식이다. 이 절차는 UNCODE (UNcertainty COmpliant DEsign)로 명명되어 사용된 바 있으나, 국내에서는 아직 적용 결과가 소개되지 않고 있다. 따라서 본 연구에서는 UNCODE의 수학적 구성 절차를 소개함과 함께 북한강수계에 위치한 수력발전댐(화천댐, 춘천댐, 의암댐, 청평댐)의 연최대유입량을 사용하여 최적설계홍수량을 산정하고 이 결과를 기존 홍수빈도분석 결과와 비교하였다. 불확실성이 고려된 총 기대비용함수로부터 확률분포함수들(Gumbel 및 GEV)의 모수를 추출하는 과정에서 Metropolis-Hastings 알고리즘을 사용하여 불확실성의 범위를 추정하였으며, 비용-편익 분석기법에 사용되는 비용 및 피해함수는 수학적 구성의 편의성을 위하여 1차 선형함수로 가정되었다. 4개의 발전용댐, 2개의 확률분포 및 2개의 재현기간에 대하여 최적설계홍수량의 중앙값이 기존 홍수빈도분석 절차에 의해 산정된 설계홍수량보다 일정 정도 큰 값으로 산정됨을 알 수 있었다. 향후에는 본 연구에서 적용된 절차를 간단한 수식형태로 함수화하여 발전용댐 운영의 실무업무나 하천기본계획의 수립 등에 있어 비용-편익분석 기법의 적용성을 높이기 위한 연구가 필요할 것으로 판단된다.

• 한국CDE학회논문집
• /
• 제16권1호
• /
• pp.61-72
• /
• 2011

As the customer's needs for diverse colors, the process of bus painting shop is becoming more and more complex. In particular, frequent changes of paint colors in each spray process require the cleaning of the painting nozzles and setting them up for the new paints, which results in increased time and cost and reduced production. This also increases environmental influences. This paper proposes, as a solution to this issue, the use of color selection field (CSF). CSF is physically a system of conveyors that are used to rearrange objects in a flow line. CSF is proposed, in this paper, to be introduced right before the spray process so that buses are better grouped according to their desired colors. Various parameters of the CSF, such as the number of conveyors and algorithms to determine the rearranged sequence of buses, have been determined by running simulations using the digital manufacturing technology, and investigating the simulation results. As an outcome of the proposed solution, the CSF system is expected to reduce approximately 30% of the nozzle cleaning cost for a Korean motor company case, which will not only benefit the company economically, but will also benefit the environment.

• 복식문화연구
• /
• 제24권2호
• /
• pp.218-232
• /
• 2016

The purpose of this study was to investigate the differences in various fashion lifestyle segments' perceived benefits and design preferences for outdoor clothing to improve the development of outdoor clothing. Data were collected by questionnaire from 600 subjects aged 30 years and over with experience purchasing outdoor clothing in the past year. Frequency analysis, factor analysis, cluster analysis, reliability analysis, ANOVA, and chi-square analysis were used for the data analysis. The results of this study were as follows. Four segments were identified based on fashion lifestyle: manifoldly conscious, sensation conscious, practicality conscious, and brand conscious. Perceived outdoor clothing benefits generated three dimensions, including premium brand, practicality, and functionality, and preferred image produced two factors, tasteful/refined and comfortable/casual. Significant differences were found in the purpose of purchasing outdoor clothing, perceived benefit, and image and t-shirt pattern design preference among the segments. The manifoldly conscious group had a higher tendency to pursue various benefits and images of outdoor clothing and to prefer t-shirt textile designs with foulards and stripes. The sensation conscious group considered fashion and individuality in daily life but not in outdoor clothing. The practicality conscious group showed a preference for simple and casual styles with functionality and foulard patterns for t-shirts. The brand conscious group tended to prefer a striking design to functionality. This study is expected to be used as preliminary data for merchandising planning of outdoor clothing.

• 설비공학논문집
• /
• 제22권4호
• /
• pp.181-188
• /
• 2010

The objectives of this study are to analyze the possibility of the landfill gas recycling for the middle and small scale landfills where the recycling facilities are not installed in Korea. It was found that the power generation plants by landfill gas were installed in domestic 15 landfills and the gas engine generation was adopted in 14 places. As the result of economic analysis, the landfill gas recycling is found to be available in 12 places and CERs of 153,693 $tCO_{2e}$ can be secured per year. Through the reduction of the air pollutants and VOCs, the social benefits of 730 million won accrue per year. Also, the power production of 18.8 GWh will substitute the crude oil imports of 4,048 TOE and the revenue of 2.49 billion won is expected to power trading. It is also found that the power generation plants by landfill gas will give the social benefits such as the reduction of the environmental problems and the substitution effect of crude oil imports.

• 한국조경학회지
• /
• 제32권3호
• /
• pp.114-125
• /
• 2004

On the assumption that marketing is a useful technique to activate park use, this study aims to find what benefits people pursue and how much they attain them through a park visit. To achieve this, the survey of a Benefits-Sought for a park was conducted at four major parks in the city of Taejon and an Importance-Performance Analysis(IPA) was conducted. Additionally, a Present Condition survey was performed with the park managers. As a result, first, it was found that major benefits are a comfortable rest, an escape from bustling city life, to see natural scenery and to promote physical health, and so forth. Second, performance was relatively lower than importance in the case of recreation and leisure activities, which means that facilities should be improved and programs for park use should be developed. Third, at GaYang park, importance and performance are good in balance. DongChunDang park and Seattle park have 5 items and 7 items for which immediate improvements are required. Saemmeury park generally shows good proportions and it can be much activated by improving the learning and experiencing activities. The results objectively show conditions of neighborhood parks in the city of Taejon from a view of park users. Therefore, it is expected that the results would be useful in determining priorities when improving park facilities or their programs.

• 정보학연구
• /
• 제9권3호
• /
• pp.15-25
• /
• 2006

Currently there is fast flow of America and South Korea FTA negotiation being issued. Aim of FTA, by having free trade between two countries to gain their economical benefit. Few benefits can be expected by Korea joining FTA with America It will increase export as well as increase in overseas investment and this will lead to booming of services industry. After America and Korea FTA Discussion being announced around the world, Australia and EU also has interest of doing FTA with South Korea, which mean that America and Korea FTA has effect of bring in the overseas interest of FTA to South Korea. Expectation of American can be, create the market in South Korea to gain benefit as well as able to check out the economical issue of north east Asia country such as China and Japan. Since American side has high agreement with the make FTA with South Korea, South Korea now has to make own decision about this matter. Since Korean economy highly influence by world trade, to survive from market competition with China and Japan, Korea must involve in Free trade with world.

• 한국시스템다이내믹스연구
• /
• 제14권3호
• /
• pp.105-134
• /
• 2013

Electrical construction business has public and professional characters. It may require appropriate interventions of the government because these business activities stand for not only profit-seeking competition, but also supplies of one of the key functions in our society. In other words, public benefit and private benefit are still in existence. The government therefore considers such an aspect of public importance of the business sector and needs to plan to adjust technical and engineering manpower of this market. This study focuses on the imbalance for labor supply and demand of technical engineer in electrical construction business. A system dynamics analysis is applied to understand and simulate the imbalance as a soft approach. It has the merit of causal loop diagram to alleviate the limitation of data lack problem. We find that excess demand is expected from 2010 to 2011, and excess supply is predicted from 2012 to 2021 about the manpower of technical engineer. It shows considerable disagreement between the supply and demand of human resource. So we suggest that it is strong necessity to construct statistics infrastructure for a manpower supply and demand plan.

• 에너지공학
• /
• 제10권3호
• /
• pp.177-182
• /
• 2001

본 연구는 경유승용차(HSDI 경유엔진) 도입에 대해 소비자 측면, 사회적 측면의 경제적 효과를 분석하고자 하였다. 먼저, 생애비용을 고려한 소비자 경제성분석 결과 승용차 수명 10년, 연간 평균 주행거리를 20.000km로 가정할 때 승용차 1대당 연료비 절감액은 13,836천원으로 추정된다. 사회적 편익은 평균 주행거리 20,000km 기준 경유승용차 관매 10% 증가 전제시 휘발유 승용차 대비 2002년부터 이익이 실현되기 시작하여 2010년에 1,541억원의 편익이 발생하는 것으로 추산된다. 사회적 누적편익은 판매량 10% 증가 가정시 20,000km 주행시 2010년까지 6,368억원의 편익이 발생할 것으로 보인다.