• Journal of the Korea Society for Simulation
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• v.24 no.3
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• pp.17-26
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• 2015

A cluster tool used in many kinds of semiconductor processes for improving the performance and the quality of wafers has a simple configuration, but its schedule is not easy because of its parallel processing module, a lack of intermediate buffers, and time constraints. While there have been many studies on its schedule, most of them have focused on full cycles in which identical work cycles are repeated under constant task times. In this research, we suggest strategies of start-up transient scheduling which satisfies time constraints and converges into a desirable steady schedule for full work cycle. The proposed schedules are expected robust under the stationary stochastic task times. Finally, we show that the strategies make schedules enters the desirable steady schedule and robust using the simulation.

• Transportation Technology and Policy
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• v.11 no.2
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• pp.10-21
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• 2014

• 한국ITS학회:학술대회논문집
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• 2004.11a
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• pp.58-63
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• 2004

• Korean Journal of Construction Engineering and Management
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• v.8 no.4
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• pp.194-202
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• 2007

The earth work has been improved with the utilization of capital intensive equipments. However, work performance is not satisfactory yet due to its experience-oriented characteristics in selecting the combination of earth work equipments. Therefore, it is required to study on appropriate and systematic methods in selecting a set of equipments for earth work in order to optimize the cost and time as well as to improve the productivity. The objectives of this paper are as followed : (1) developing an optimum combination model of earth work equipments by using a system dynamics technique. (2) testing and evaluating the model by the sample application to a case study. The research is limited to the work of excavating, loading and hauling. The suggested model is proved in practice, so it will assist engineers to make the proper decision for equipment planning of earth work.

• Journal of KIISE:Computing Practices and Letters
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• v.13 no.4
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• pp.193-204
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• 2007

As the scale of broadcasting systems gets bigger and the functionality of broadcasting devices becomes diverse, networking facilities are being incorporated within recent broadcasting devices. Although networked devices can perform many of the additional functionalities, an effective management becomes a difficult issue. Therefore, it is essential to provide an automated management system for monitoring and controlling distributed broadcasting devices across a network. SNMP (Simple Network Management System) is one of the enabling technologies that we could adopt when we build such a system. However, SNMP-based solution has its limitations. In this paper. we propose the TMS800 system, which is a metadata-based device management system on top of SNMP framework. The system is specifically designed for the management of distributed broadcasting devices. It makes it possible to monitor not only the status of devices, but also the videos in the form of still images. Remote control and real-time notification facilities are also provided.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.153-162
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• 2017

Weapon systems have been developed with high technology electronic equipment due to technology growth. In addition, the capital, operational and maintenance costs of weapon systems have all increased. However, cost of operation and maintenance for weapon systems has been decreased relatively compared to the increased capital cost of weapon systems. Therefore, the defense industry needs to research the life cycle cost of weapon systems that have high operational and maintenance costs. This paper focuses on maintenance equipment for the operation and maintenance of weapon systems. Recently, it seems that the weapon systems that have periodic calibration with maintenance equipment are valid. The equipment requires periodic calibration by the manufacturer to check its own validation. Basically, customers demand high reliability devices from foreign companies that have qualified in the global market. Therefore, the tools need to be calibrated overseas. In other words, weapon systems are not available when the equipment has to be calibrated overseas because the systems require validation with valid maintenance equipment. A purpose of this paper is to compare the loss costs that arise from the calibration of the equipment overseas and the purchasing cost of the tools. Finally, the research shows the number of equipment that customers need to minimize the cost. This research will help to improve the efficiency of operation of weapon systems and solve the problems associated with the need for maintenance overseas.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.22 no.2
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• pp.93-104
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• 2023

Currently, the permanent road traffic volume surveys under Road Act are conducted using a intrusive Automatic Vehicle Classification (AVC) equipments to classify 12 categories of vehicles. However, intrusive AVC equipment inevitably have friction with vehicles, and physical damage to sensors due to cracks in roads, plastic deformation, and road construction decreases the operation rate. As a result, accuracy and reliability in actual operation are deteriorated, and maintenance costs are also increasing. With the recent development of ITS technology, research to replace the intrusive AVC equipment is being conducted. However multiple equipments or self-built DB operations were required to classify 12 categories of vehicles. Therefore, this study attempted to prepare a method for classifying 12 categories of vehicles using vehicle specification information of the Vehicle Management Information System(VMIS), which is collected and managed in accordance with Motor Vehicle Management Act. In the future, it is expected to be used to upgrade and diversify road traffic statistics using vehicle specifications such as the introduction of a road traffic survey system using Automatic Number Plate Recognition(ANPR) and classification of eco-friendly vehicles.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.12 no.3
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• pp.11-18
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• 2013

Since 1996, Korean National Police Agency has been promoting a project for installation of Automated Speed Enforcement (ASE) system aiming at reduction of accidents. The number has increased to 5,348 stations throughout country as of December 2012. Recently, the Section Speed Enforcement Systems have been installed at many sites to produce a general effect well beyond the localised effect at overt fixed camera sites. In this study aims, we have analyzed the effects of the Section Speed Enforcement System at the Misiryeong tunnel section. We have found that there were a statistically significant 21.4%~31.% reduction of the average speed and 45.9% reduction in a number of traffic accidents per month. Accordingly, the study indicates that the Section Speed Enforcement Systems at Misiryeong tunnel section has effective to produce road safety.

• Journal of Korea Society of Industrial Information Systems
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• v.25 no.4
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• pp.17-27
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• 2020

In this paper, we proposed verification methods to prove the effectiveness of automatic test equipment (ATE) for weapon systems. Since the test results from the unproven ATE is not reliable and its use is limited as objective data, it is essential to verify the test equipment in order to guarantee the quality level of the unit under test (UUT). Through the suggested methods, it is applied to the ATE of the tactical information communications network (TICN) system to confirm the verification results and to describe the validation results.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2006.06b
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• pp.363-366
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• 2006

In the port, Yard Crane is very important. If container crane or transfer crane broke down, it costs much money for delaying of work during the period of repair or reorder. But, we can not have enough spare parts for its high cost. It is necessary for having the reliability of crane through the effective preventive maintenance and failure analysis. In this paper, we analysed the system's function and failure mechanism of transfer crane which is main equipment in the yard. Also, we standardized the failure and maintenance work using the historical data of failure and maintenance. This study which is the basic work for IT of equipment operation and maintenance is going to be new attempt for optimal design of next generation equipment and operation policy of equipment.