• Journal of the military operations research society of Korea
• /
• v.6 no.1
• /
• pp.79-92
• /
• 1980

In cost-only incentive contract the emphasis is the attainment of efficient and effective cost control. In contrast multiple incentives contract correlates contractor's profit motives with the generalized government objective function, the decision variables of which are performance or quality (technical progress), time or schedule (timely development and delivery) and the cost (efficient and effective cost control) Under multiple incentive structure, it is essential to formulate the trade-off curves between cost and performance, which are called iso-fee curves. Trade-off curves depict the combination of cost and performance achievement for which the contractor will be rewarded with the same fee. The basic function of trade-off curves is to show he the contractor will be motivated by incentive arragement to trade off or sacrifice the achievement in one incentive element for the acnievment in another.

• Smart Structures and Systems
• /
• v.16 no.3
• /
• pp.435-457
• /
• 2015

The most widely known form of multifunctional aircraft structure is smart structures for structural health monitoring (SHM). The aim is to provide automated systems whose purposes are to identify and to characterize possible damage within structures by using a network of actuators and sensors. Unfortunately, environmental and operational variability render many of the proposed damage detection methods difficult to successfully be applied. In this paper, an original robust damage detection approach using output-only vibration data is proposed. It is based on independent component analysis and matrix perturbation analysis, where an analytical threshold is proposed to get rid of statistical assumptions usually performed in damage detection approach. The effectiveness of the proposed SHM method is demonstrated numerically using finite element simulations and experimentally through a conformal load-bearing antenna structure and composite plates instrumented with piezoelectric ceramic materials.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2003.05a
• /
• pp.514-519
• /
• 2003

The aircraft engine is usually supported by rolling element bearings and has a small damping rate, which is vol y sensitive to external force. The high-performance requirement of the rotors leads to complex assembly designs and are more flexible. Squeeze film dampers (SFDs) are introduced to provide damping while crossing the critical speeds and stability to the rotor s :stem. Hence, the focus of the present investigation is on the decision of an optimal size of the flexible rotor system supported by the squeeze film dampers to minimize the maximum transmitted load and unbalance response over a range operating speeds. The enhanced genetic algorithm (EGA), which was developed by authors, is used in the optimization process. This algorithm is based on the synthesis of a modified genetic algorithm and simplex method. The results show significant benefits in using EGA when compared with nonlinear programming (NLP).

• Proceedings of the KIEE Conference
• /
• 1995.07b
• /
• pp.637-639
• /
• 1995

Since power systems tend to be more large and complex, expert system substituted for the decision-making achieved by the power system operation expert is required. So far, expert system has been used for fault diagonosis and voltage-reactive power control and so on. In the expert system developed using 'C' language, the faulted element is estimated using the AND operation of lists which are acquired from the information on operated relays. It is also considered to identify the misoperation of protective devices using CF(Certainty Factor), and operation failure of those using the data base of parameter group list. The developed expert system is applied to a 6-bus sample system and through the case studies. It is shown that the expert system is very useful.

• KIEAE Journal
• /
• v.12 no.6
• /
• pp.11-22
• /
• 2012

The paper aims to establish planning elements of planned-ecovillages, and analyze the cognizance of residents as well as experts' evaluation so as to examine the awareness of actual residents. The planned-ecovillage allows residents to participate in the organization of the ecovillage to the construction stage. Unlike general ecovillages, planned-ecovillages have a difference as they introduce planning elements by autonomous decision-making through discussions and meetings among residents. The present age is at its turning point. While a fatal impact to human life, including energy shortage and environmental pollution are expected, we may be able to suggest an alternative solution and triggered the initiation, such as a future-oriented ecovillage that enables environmentally-friendly and sustainable living, namely planned-ecovillages.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.34 no.4
• /
• pp.162-168
• /
• 2011

The most generalized form of the triadic operating policy for a controllable M/G/I queueing model is analyzed to obtain fundamental relations among the other forms of operating policies based on its corresponding expected busy period. Since it consists of three decision variables N, T and D, it could be possible to decompose into the simple, the dyadic and other forms of the triadic operating policies. The procedures to decompose the most generalized triadic policy into other forms of operating policies could provide a general methodology to identify each element associated with it.

• Journal of Construction Engineering and Project Management
• /
• v.4 no.4
• /
• pp.17-32
• /
• 2014

In a competitive business environment, like construction, achieving customer satisfaction has been identified as an important element for measuring project's success and sustaining competitive advantage. Traditionally, customers were expelled from the product development process. Little effort was done, in the past to identify the factors that lead to customer satisfaction and hence, use them for product improvement. Organizations that adopted that approach, encountered the risk of losing their customers. In construction, end-users of governmental housing projects were excluded from the design decision making process and accordingly, their requirements were not reflected in design. Although a number national customer satisfaction indices and barometers have been developed worldwide, they have their own limitations and shortcomings. This paper aims to develop an international index for customer satisfaction in the construction Industry. For the first time in construction literature, this research identified, validated and classified 45 drivers for achieving customer satisfaction in the construction industry.

• Journal of Electrical Engineering and Technology
• /
• v.7 no.2
• /
• pp.200-206
• /
• 2012

In order to develop a deep-underground great train express (GTX) in South Korea, the specifications decision and development of a traction control system (including an inverter and a traction motor), which considers a variety of route conditions, must be advanced. In this study, we examined the running resistance properties of a high-speed traction system based on a variety of tunnel types and vehicle organization methods. Then, we studied the power requirements necessary for the traction motor to maintain balanced speed in the high-speed traction system. From this, we determined the design criteria for the development of a high-speed traction system for use in the deep-underground GTX. Finally, we designed a linear induction motor (LIM) for a propulsion system, and we used the finite element method (FEM) to analyze its performance as it travelled through deep-underground tunnels.

• Journal of Information Technology Services
• /
• v.7 no.1
• /
• pp.89-101
• /
• 2008

Recently, mobile banking service comes into the spotlight in the mobile environment. Considering design theory, this empirical study focuses on understanding the characteristics of mobile banking and measuring the priority of IT composition elements organizing the mobile banking service. That is, by empirically analyzing affecting factors of mobile service acceptance as an aspect of customer, this study would like to understand important factors of mobile banking use. The result of study will be used to strategic decision making for the company providing mobile banking service and great help to reinvigorate mobile banking service.

• Interaction and multiscale mechanics
• /
• v.4 no.1
• /
• pp.49-64
• /
• 2011

A methodology for jointed rock mass characterization starts with a research based on geological data and tests in order to define the geotechnical models used to support the decision about location, orientation and shape of cavities. Afterwards a more detailed characterization of the rock mass is performed allowing the update of the geomechanical parameters defined in the previous stage. The observed results can be also used to re-evaluate the geotechnical model using inverse methodologies. Cases of large underground structures modeling are presented. The first case concerns the modeling of cavities in volcanic formations. Then, an application to a large station from the Metro do Porto project developed in heterogeneous granite formations is also presented. Finally, the last case concerns the modeling of large cavities for a hydroelectric powerhouse complex. The finite element method and finite difference method software used is acquired from Rocscience and ITASCA, respectively.