• Proceedings of the Korean Operations and Management Science Society Conference
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• 1999.04a
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• pp.262-263
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• 1999

• Industrial Engineering and Management Systems
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• v.6 no.2
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• pp.125-135
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• 2007

An automated guided vehicle (AGV) system is a group of collaborating unmanned vehicles which is commonly used for transporting materials within manufacturing, warehousing, or distribution systems. The performance of an AGV system depends on the dispatching rules used to assign vehicles to pickup requests, the vehicle routing protocols, and the home location of idle vehicles, which are called dwell points. In manufacturing and distribution environments which emphasize just-in-time principles, performance measures for material handling are based on response times for pickup requests and equipment utilization. In an AGV system, the response time for a pickup request is the time that it takes for the vehicle to travel from its dwell point to the pickup station. In this article, an exact dynamic programming algorithm for selecting dwell points in a tandem-loop multiple-vehicle AGV system is presented. The objective of the model is to minimize the maximum response time for all pickup requests in a given shift. The recursive algorithm considers time restrictions on the availability of vehicles during the shift.

• Proceedings of the Korean Information Science Society Conference
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• 2005.07b
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• pp.391-393
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• 2005

DMS(Data Management Server)시스템은 DVM(Digital Variable Multi Air conditioning system) 관리, 제어, 모니터링을 수행하는 시스템으로 OSGi Service Platform을 미들웨어로 채택하고 있다. 본 논문에서는 OSGi Alliance에서 제공하는 Test Harness와 Test Suite을 기반으로 본 연구진이 개발한 OSGi Automated Test Toolkit인 MIRACLE을 이용한 DMS시스템 테스트 사례 연구에 관해 기술한다. 본 논문을 통해, MIRACLE을 이용한 임베디드 시스템에서의 OSGi Service Platform의 테스트 자동화에 대해 기여 할 수 있도록 한다.

• Journal of Communications and Networks
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• v.12 no.4
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• pp.382-394
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• 2010

Cross-domain event information sharing is a topic of great interest in the area of event based network management. In this work we use data sets which represent actual attacks in the operational Internet. We analyze the data sets to understand the dynamics of the attacks and then go onto show the effectiveness of sharing incident related information to contain these attacks. We describe universal data acquisition system for event based management (UniDAS), a novel system for secure and automated cross-domain event information sharing. The system uses a generic, structured data format based on a standardized incident object description and exchange format (IODEF). IODEF is an XML-based extensible data format for security incident information exchange. We propose a simple and effective security model for IODEF and apply it to the secure and automated generic event information sharing system UniDAS. We present the system we have developed and evaluate its effectiveness.

• Proceedings of the Safety Management and Science Conference
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• 2004.11a
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• pp.171-182
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• 2004

Korea Railroad Research Institute(KRRI) has developed the rubber-tired AGT system from 1999 to 2004. The rubber-tired AGT vehicle is now on test for its performance and function in the Gyeong-San test line. Tn this paper, we provide the reliability management plan to assure required the RAMS(reliability, availability, maintainability & safety) of the AGT vehicle system.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.364-367
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• 2008

Earthwork is very equipment-intensive task and researches related to automated excavation have been conducted. There is an issue to secure the safety for an automated excavating system. Therefore, this paper focuses on how to improve safety for semi- or fully-automated backhoe excavation. The primary objective of this research is to develop object detection algorithm for automated safety system in excavation work. In order to satisfy the research objective, a diverse sensing technologies are investigated and analysed in terms of functions, durability, and reliability and verified its performance by several tests. The authors developed the objects detecting algorithm for user interface program using laser sensor. The results of this study would be the basis for developing the automated object detection system.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.242-249
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• 2009

High-rise construction sites, especially those situated in spatially constrained urban areas, have difficulties in timely delivery of materials. Modern techniques such as Just-in-time delivery, and use of information technology such as Project Management Information System (PMIS), are targeted to improve the efficiency of the logistics. Such IT-driven management techniques can be further benefited from state-of-the-art devices such as Radio Frequency Identification (RFID) tags and Ubiquitous Sensor Networks (USN), which has resulted in notable achievements in automated logistics management at the construction sites. Based on those achievements, this research develops USN hardware toolkits for construction lifts, which aims to be automated the vertical material delivery by sensing the material information and routing it automatically to the right place. The gathered information from the sensors can also be used for monitoring the overall status. The developed system will be tested in the actual high-rise construction sites to assess the system's feasibility. The proposed system is being implemented using Zigbee communication modules and RFID sensor networks which will communicate with the intelligent palette system (previously developed by the authors). To support the system, a lift-mountable intelligent toolkit is under development. Its feasibility test will be conducted by applying the implemented system to a test bed and then analyzing efficiency of the system and the toolkit. The collected test data will be provided as a basis of autonomous vertical transport equipment development. From this research, efficient management of the material lift is expected with increased accuracy, as well as better management of overall construction schedule benefited from the system. Further research will be expected to develop a smart construction lift, which will eliminate the need for human supervision, thus enabling a real 'autonomous' operation of the system.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.1324-1327
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• 2009

Social infrastructure is the basis of public welfare and should be recognized and managed as important assets. Bridge is one of the most important infrastructures to be managed systematically because the impact of the failure is critical. It is essential to monitor the performance of bridges in order to manage them as an asset. But current analytical methods such as predictive modeling and structural analysis are very complicated and difficult to use in practice. To apply these methods, structural and material condition data collection should be performed in each element of bridge. But it is difficult to collect these detailed data in large numbers and various kinds of bridges. Therefore, it is necessary to collect data of major measurement items and predict the life of bridges roughly with advanced information technologies. When certain measurement items reach predefined limits in the monitoring bridges, precise performance measurement will be done by detailed site measurement. This paper describes the selection of major measurement items that can represent the tendency of bridge life and introduces automated bridge data collection test-bed using wireless sensor network technology. The following will be major parts of this paper: 1) Examining the features of conventional bridge management system and data collection method 2) Mileage concept as a bridge life indicator and measuring method of the indicator 3) Test-bed of automated and real-time based bridge life indicator monitoring system using wireless sensor network

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 1998.10a
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• pp.137-141
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• 1998

Todays the efficient management of container has not been realized in container terminal, because of the excessive quantity of container transported and manual system. For the efficient and automated management of container in terminal, the automated container identifier recognition system in terminal is a significant problem. However, the identifier recognition rate is decreased owing to the difficulty of image preprocessing caused the refraction of container surface, the change of weather and the damaged identifier characters. Therefore, this paper proposes more accurate system for container identifier recognition as suggestion of Line-Scan Proper Region Detect for stronger preprocessing against external noisy element and Moment Back-Propagation Neural Network to recognize identifier.

• Journal of Korean Port Research
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• v.12 no.2
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• pp.225-232
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• 1998

Todays, the efficient management of container has not been realized in container terminal, because of the excessive quantity of container transported and manual system. For the efficient and automated management of container in terminal, the automated container identifier recognition system in terminal is a significant problem. However, the identifier recognition rate is decreased owing to the difficulty of image preprocessing caused the refraction of container surface, the change of weather and the damaged identifier characters. Therefore, this paper proposes more accurate system for container identifier recognition as suggestion of LSPRD(Line-Scan Proper Region Detection) for stronger preprocessing against external noisy element and MBP(Momentum Back-Propagation) neural network to recognize the identifier.