• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.57 no.11
• /
• pp.2001-2005
• /
• 2008

This paper presents a design of a simulation apparatus to evaluate an operational control algorithm for the PRT system. PRT systems require very short headways to increase the line capacity and a very reliable vehicle control algorithm for avoidance of the impact between vehicles. Therefore, it can be said that the development of an reliable operational control algorithm for the PRT systems is much more important than that of the hardware configurations. In this paper an apparatus is proposed which is composed of virtual vehicles, a central control system, a man-machine interface and monitoring device, making it possible for the designed operational control algorithm to be implemented and tested. For the test of the proposed apparatus a test operational control algorithm is designed and the experimental results show the effectiveness of the proposed simulation apparatus for test and evaluation of the PRT operational control algorithms.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.32 no.3
• /
• pp.127-134
• /
• 2009

RAM(Reliability, Availability, Maintainability) is important performance factor to keep combat readiness and optimize operational and maintenance cost of weapon systems. This paper discusses the method to establish RAM for combat readiness by using field failure data from similarity equipments. Operational availability is estimated from a binomial distribution function of user's operational conditions such as combat readiness preservation probability, operational rate, operational availability and total number of equipment. Reliability and maintainability is estimated from field failure data from similarity equipment to accomplish operational availability. The effectiveness of established RAM is verified through analysis of combat readiness preservation probability and mission reliability. A case study of weapon system illustrates the process of the proposed method.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2000.11a
• /
• pp.353-357
• /
• 2000

A dimensioning system in a manufacturing process is often complex, especially when a lot of operations are involved in the process. Determination of operational dimensions and tolerances becomes even more complicated if there exist inconsistencies between operational and design relationships among operational dimensions in machining. This chart furnishes a record of the relationships in an easy-to-grasp form, proves that sufficient stock for a cut is available even under adverse conditions, and also proves that separate operations, when taken together, will harmonize as desired. In this paper, various existing roles of the chart have been extended to an operational routing sheet by generating it automatically, providing machining conditions, and verifying operational tolerances.

• The Transactions of the Korean Institute of Electrical Engineers A
• /
• v.48 no.6
• /
• pp.753-759
• /
• 1999

BPF(block pulse function) has been used widely in the system analysis and controller design. The integral operational matrix of BPF converts the system represented in the form of the differential equation into the algebraic problem. Therefore, it is important to reduce the error caused by the integral operational matrix. In this paper, a new integral operational matrix is derived from the approximating function using Lagrange's interpolation formula. Comparing the proposed integral operational matrix with another, the result by proposed matrix is closer to the real value than that by the conventional matrix. The usefulness of th proposed method is also verified by numerical examples.

• Ocean and Polar Research
• /
• v.31 no.4
• /
• pp.361-368
• /
• 2009

An operational oceanographic system needs to be established for the preservation and management of marine environments and resources, and also to secure the safety and efficiency of marine operations in Korea. One of the major roles of operational oceanography is to deliver ocean science products which can meet the requirements of users such as marine industries, the general public, government agencies, and scientific research communities. Technical issues in relation to development of an effective operational oceanographic system in Korea are identified and discussed. Among others, cooperation among the agencies in ocean, meteorology, hydrology and environment, and also among those of neighboring countries is important for the development of an effective operational oceanographic system. The strategy for building a system that meets the demands of users, with consideration to potential problems, are explored.

• Nuclear Engineering and Technology
• /
• v.31 no.1
• /
• pp.49-57
• /
• 1999

It has been a critical issue to predict the safety critical software reliability in nuclear engineering area. For many years, many researches have focused on the quantification of software reliability and there have been many models developed to quantify software reliability. Most software reliability models estimate the reliability with the failure data collected during the test assuming that the test environments well represent the operation profile. User's interest is however on the operational reliability rather than on the test reliability. The experiences show that the operational reliability is higher than the test reliability. With the assumption that the difference in reliability results from the change of environment, from testing to operation, testing environment factors comprising the aging factor and the coverage factor are developed in this paper and used to predict the ultimate operational reliability with the failure data in testing phase. It is by incorporating test environments applied beyond the operational profile into testing environment factors. The application results show that the proposed method can estimate the operational reliability accurately.

• Journal of the Korea Safety Management & Science
• /
• v.9 no.6
• /
• pp.9-17
• /
• 2007

This article addresses the question of how the operational architecture for a railway safety information system should be developed. A successful railway safety information system can be developed by fully reflecting the business process and needs at the enterprise level. To date, there has been minimal research effort towards the development of the operational architecture for a railway safety information system. To this end, a variety of enterprise architectures have been studied so far. In this paper, as an important guideline, DoDAF (Architecture Framework) is selected to be used in developing a railway safety information system. In particular, we propose a method to implement the operational architecture based on DoDAF.

• Korean Management Science Review
• /
• v.21 no.2
• /
• pp.167-189
• /
• 2004

Cooperative and integrative partnerships between buyers and suppliers are very important for effective operations. Such partnerships should be based on various information technologies developed in recent years. Therefore, we investigated the relationship among IT performance, IT infrastructure and supply chain performance in buyer-supplier linkage using exploratory examination. This analysis is based on survey results of buyer-supplier practitioners in Korean electronics industry. Specifically, we used factor analysis, correlation analysis, and regression analysis. Major findings are as follows. First. buyers' IT performance contributed to enhance their operational & financial performance, and satisfaction. Second, buyers' IT infrastructure improved their financial performance and satisfaction but showed mixed effects on operational performance. Third, suppliers' operational performance enhanced buyers' operational & financial performance, and satisfaction. Fourth, suppliers' IT performance strengthened their operational & financial performance, and satisfaction. Fifth, suppliers' IT infrastructure showed positive relationships with operational performance and satisfaction.

• Korean Management Science Review
• /
• v.24 no.2
• /
• pp.81-93
• /
• 2007

Achieving a target operational availability is more economical and efficient than having many quantities of the weapon system, since the cost of weapon system becomes expensive. The intent of this study is twofold; first, we develop the simulation model to determine the optimal inventory level of the maintenance float while achieving a target operational availability of the Korean-made helicopter. The quantity decision model considers following factors such as a reliability. a turn around time(TAT). a protection level for inventory, and so on. Second, we analyze whether the existence of a lateral transshipment among bases and the reduction of TAT relate to an inventory level and the operational availability. The research result shows that both TAT and lateral transshipment have an effect on reducing the inventory level of the maintenance float and improving an operational availability.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.15 no.5
• /
• pp.651-659
• /
• 2012

Target operational availability setting is the first step to setting up a goal which a weapon system development project have to achieve and doing RAM analysis during whole life of a weapon system. It is important as a key factor to doing RAM analysis in the early phase of weapon system development. This paper present a methodology to set a target operational availability for, especially, a warship when it develop. This methodology uses Operational Mode Summary/Mission Profile(OMS/MP) of the developing warship and RAM analysis results of similar warships to calculate wartime and peacetime target operational availability. It will be used in early phase of not only warship development but also army or aircraft weapon systems when these develop.