• 대한산업공학회지
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• 제31권1호
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• pp.87-98
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• 2005

This research investigates economic-statistical characteristics of variable sampling size and interval (VSSI)$\bar{X}$charts under two assignable causes. A Markov chain approach is employed in order to calculate average run length (ARL) and average time to signal (ATS). Six transient states are derived by carefully defining the state. A steady state cost rate function is constructed based on Lorenzen and Vance(1986) model. The cost rate function is optimized with respect to six design parameters for designing the VSSI $\bar{X}$ charts. Computational experiments show that the VSSI $\bar{X}$ chart is superior to the Shewhart $\bar{X}$ chart in the economic-statistical sense, even under two assignable causes. A comparative study shows that the cost rate may increase up to almost 30% by overlooking the second cause. Critical input parameters are also derived from a sensitivity study and a few guideline graphs are provided for determining the design parameters.

• 한국HCI학회논문지
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• 제11권1호
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• pp.11-19
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• 2016

본 연구는 사용자 경험(UX)에 대한 경제적 가치 평가 모델을 탐색하고 적용하는 것을 목적으로 수행되었다. 스마트폰 잠금해제 UX를 대상으로 터치형, 지문인식, 홍채인식에 대해 조건부 가치측정법(contingent valuation method, CVM)을 적용하였다. 경제적 가치를 산출하기 위한 가치추정법 중에서 조건부 가치측정법을 선택한 이유는 잠금해제와 같은 인터페이스 요소들은 스마트폰을 이용할 때 중요한 사용자 경험적 가치이지만 시장에서 별개로 거래되지 않는 비 시장 재화이기 때문이다. 스마트폰 잠금해제를 조건부 가치측정법 중 이중 양분선택형 방식(double-bounded dichotomous choice)으로 설문조사하여 로짓 모형으로 분석한 결과 터치형 잠금해제 인터페이스는 529원, 지문인식 잠금해제는 4,214원, 홍채인식 잠금해제는 1,376원으로 경제적 가치가 나타났다. 즉, 지문인식 잠금해제가 가장 높은 경제적 가치를 나타냈으며, 그 다음으로 홍채인식, 터치형 순이었다. 이 연구의 주요 기여점은 UX 디자인에 대해 경제적 가치를 평가하는 방법론적 시도를 수행하였고, 체계적이고 신뢰도 있는 결과를 산출하였다는 점이다.

• 디자인학연구
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• 제19권1호
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• pp.27-38
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• 2006

현재 일본의 각 자치체에서는 지역주민에게 만족도를 최대화하기 위한 방안으로 유니버설디자인 정책의 도입이 활발히 전개되고 있다. 본 연구는 자치단체가 유니버설디자인을 정책에 도입하게 된 배경과 각 자치체에서 추진되고 있는 시책들을 조사하고 그 추진요건 등에 대해 제시한 것이다. 자치체에서 UD 추진의 필요성을 종합하면 지방시대의 정착과 그 내실화를 추진해가는 과정에 있어서 다양한 문제를 안고 있으나, 사회 및 경제적 배경으로는 저출산화 현상과 고령사회의 진행, 사회 경제의 성숙화에 의한 가치관의 다양화 등을 꼽을 수 있다. 사람들의 가치관은 경제지상주의에서 탈피하여 물질적인 만족만이 아닌 문화, 환경, 예술 등이 경제 이상의 선상에서 존중하고 생활의 질적 향상이 중요시되고 있다. 그러한 가운데 보다 많은 사용자에게 사용이 편리한 디자인이라는 개념으로 대두된 유니버설디자인은 21세기 디자인의 기본 컨셉으로 주목받게 이르렀다. 오늘날 일본의 각 자치체에서는 홈페이지, UD 지침과 연구보고서, 각종 워크숍 등의 방법을 통해 지역 커뮤니티에 UD의 자연스러운 도입과 적용을 위해 다양한 노력을 경주하고 있다. 특히 공통적 시책 내용으로는 공공 공간 및 설비의 유니버설디자인 정책 및 기타제품 제조에 있어서의 유니버설디자인 정책, 정보에 있어서의 유니버설디자인 정책 등이 있다. 유니버설디자인 정책의 시행은 1) 사업의 기획 조정 정책입안 결정의 과정 2) 시책의 실시 과정 3) 모든 과정과 결과의 검증 과정이라는 프로세스를 중요시하며, 각 요소에는 행정과 지역주민 시민단체, 기업 등 3자의 고른 역할참여가 불가결함을 알 수 있다.

• 산업공학
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• 제23권4호
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• pp.319-326
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• 2010

The SMB supercomputing service provides a supercomputing infrastructure for Small and Medium-sized Business (SMB) to enhance the efficiency of product development activity. In this study, the economic value of SMB supercomputing service is presented. The economic value of service is comprised of a direct and an indirect economic value. A direct economic value was estimated based on the result of user survey on service effectiveness. The input-output analysis method was adopted to estimate an indirect economic value induced from a direct economic value. The future economic value based on the result of user demand survey is also presented. As a result, the annual and future economic value of service were estimated about 55,215 million won and 323,928 million won, respectively.

• 상하수도학회지
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• 제26권2호
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• pp.191-199
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• 2012

Rainwater harvesting systems (RWHS), one of measures for on site rainwater management, have been promoted by laws, regulations and guidelines and have been increased. However, more evaluation of economic feasibility on RWHS is still needed due to seasonal imbalance of rainfall and little experiences and analysis on design and operation of RWHS. In this study, we investigated tank capacity of RWHS to secure economic validity considering catchment area and water demand, which is affected by building scale. Moreover, sensitivity analysis was performed to examine the effect of design factors, cost items and increase rate of water service charge on economic feasibility. The BCR (benefit cost ratio) is proportional to the increase in tank capacity. It is increased steeply in small tank capacity due to the effect of cost and, since then, gently in middle and large tank capacity. In case of 0.05 in the rate of tank volume to catchment area and 0.005 in water demand to catchment area, BCR was over one from the tank capacity of 160 $m^{3}$ taking into account of private benefits and from the tank capacity of 100 $m^{3}$ taking into account of private and public benefits. Sensitivity analysis shows that increase of water demand can improve BCR values with little cost so that it is needed to extend application of rainwater use and select a proper range of design factor. Decrease of construction and maintenance cost reduced the tank volume to secure economic validity. Finally, increase rate of water service charge had considerable impact on economic feasibility.

• 품질경영학회지
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• 제43권4호
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• pp.471-488
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• 2015

Purpose: Double sampling $T^2$ chart is a useful tool for detecting a relatively small shift in process mean when the process is controlled by multiple variables. This paper finds the optimal design of the double sampling $T^2$ chart in both economical and statistical sense under Weibull failure model. Methods: The expected cost function is mathematically derived using recursive equation approach. The optimal designs are found using a genetic algorithm for numerical examples and compared to those of single sampling $T^2$ chart. Sensitivity analysis is performed to see the parameter effects. Results: The proposed design outperforms the optimal design of the single sampling $T^2$ chart in terms of the expected cost per unit time and Type-I error rate for all the numerical examples considered. Conclusion: Double sampling $T^2$ chart can be designed to satisfy both economic and statistical requirements under Weibull failure model and the resulting design is better than the single sampling counterpart.

• 유통과학연구
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• 제13권4호
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• pp.29-33
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• 2015

Purpose - This paper aims to explain the interactive relationship between small and medium-sized enterprises' clusters and regional economic growth, with Jiangsu Province as an illustrative example. It focuses on studying the promotional effects, if any, of small and medium-sized enterprises' cluster-development on regional economic growth, and vice-versa. Research design, data, and methodology - Data were collected from the Jiangsu Statistical Yearbook and the China Industrial Economic Statistical Yearbook, by selecting 26 industries as the research subjects. The sample interval selection is 1981-2012. The data were analyzed with the dynamic panel system using stata 12.0. Results - 1) The small and medium-sized enterprises' cluster degree and Jiangsu's economic growth have a long-term stable equilibrium relationship. 2) In the short term, they have a dynamic adjustment 3) The enterprises' cluster degree leads to regional economic growth in Jiangsu, but not vice-versa. Conclusions - Small and medium-sized enterprises' clusters have an important promotional effect on Jiangsu's economic growth, especially industries with high degree of agglomeration. Therefore, the formation of these clusters can significantly improve economic growth.

• 국제학술발표논문집
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• The 5th International Conference on Construction Engineering and Project Management
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• pp.28-35
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• 2013

The construction industry has introduced the Leadership in Energy and Environmental Design (LEED) rating system to promote objective evaluations of the sustainability of buildings. Three important values to consider when implementing sustainability are the associated environmental, social, and economic impacts. Recently, researchers have begun to investigate the real estate value of LEED certified buildings in terms of the rental cost, occupancy rate, cost per unit area, and resale value in order to better understand the economic benefits of the LEED rating system. However, the economic benefits also encompass economic effects such as the impact of LEED certified buildings on neighborhood real estate values surrounding the certified buildings. This research examines whether the enhanced real estate value of LEED certified buildings in New York City extends to surrounding commercial buildings, utilizing spatial analysis via a Geographic Information System (GIS) and the hedonic pricing method to derive meaningful economic relationships. The results provide practical insights into the economic effect of LEED certified buildings that will be of interest to city officials and planners, as well as the owners, developers, investors and other stakeholders of surrounding buildings.

• 한국CDE학회논문집
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• 제17권2호
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• pp.71-78
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• 2012

Recently, the ratio of fuel cost to the operational cost of a ship is increasing according to the increase of the international oil price. Thus, many studies are being made to reduce the cost; for example, a method for acquiring the sea state information, a method for estimating fuel consumption, a method for determining the ship's optimal route, and so on. However, these studies were not incorporated together and being independently made in different fields. In this study, by improving and incorporating such studies, a method for determining a ship economic route based on the acquisition of the sea state and estimation of fuel consumption was proposed. To evaluate the applicability of the proposed method, it was applied to an optimal routing problem of the ocean area including many islands. The result shows that the proposed method can yield the economic route minimizing fuel consumption.

• 품질경영학회지
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• 제31권2호
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• pp.117-130
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• 2003

This paper investigates the economic design of synthetic control charts. The synthetic control chart has been proven to be statistically superior to the $\bar{X}$-control chart, but its economic characteristics have not been known. We develop an economic model of the synthetic control chart, based on Duncan's model. The synthetic chart has one more decision variable, the lower control limit for the conforming run length. In addition to this, the significance level and the power of the synthetic chart are more complicated than those of the $\bar{X}$-chart. These features make the optimization problem more difficult. We propose an optimization algorithm by adapting the congruent gradient algorithm. We compare the optimal cost of the synthetic chart with that of (equation omitted)-control chart, under the same input parameter set of Duncan’s. For all cases investigated, the synthetic chart shows superior to the $\bar{X}$-chart. The synthetic control chart is easy to implement, and it has better characteristics than the $\bar{X}$-chart in economical sense as well as in statistical sense, so it will be a good alternative to the traditional control charts.