• Journal of Power System Engineering
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• v.8 no.4
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• pp.17-23
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• 2004

A delivery ship is used to handle the cargo with the crane to/from the ships. The ship is inclined in the direction of a cargo which is hung on a crane. In this case, a arc shaped rail should be in the equilibrium state to get good anti rolling performance. In this study, a device and control algorithm are developed to take accurate and quick equilibrium of the rail. The device is composed of a hinged immovable support and two screw jacks. And the control algorithm demands two controllers. One controller is designed such that the screw jack 1 and 2 follow the position reference signal generated by a tilt sensor. The other controller of two degree of freedom is designed to remove the synchronous error occurred between jack 1 and jack 2. The simulation results show that the desirable control performance is achieved.

• Journal of Power System Engineering
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• v.11 no.1
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• pp.134-139
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• 2007

A delivery ship is used to handle the cargo with the crane to/from the ships. The ship is inclined in the direction of a cargo which is hung on a crane. In this case, a arc shaped rail should be in the equilibrium state to get good anti-rolling performance. In this study, a device and control algorithm are developed to take accurate and quick equilibrium of the rail. The device is composed of a hinged immovable support, screw jack and damper. And the control system is based on I-PD control law to consider of control input saturation and overshoot. The controller is composed of integral controller of feedforward path and proportional-derivative controller of feedback path. The parameters of controller is designed to follow the reference signal and to remove overshoot. The simulation results show that the desirable control performance is achieved.

• IEMEK Journal of Embedded Systems and Applications
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• v.5 no.1
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• pp.23-28
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• 2010

The automotive industry tries to provide infotainment systems to emerging automobiles. Since the infotainment systems require various peripheral devices and network connectivity, legacy operating systems such as Linux and Windows can be much preferred due to its plentiful device drivers and multimedia applications while the operating systems following OSEK standard are used for automotive electronic control units. Thus it is highly desired that the system software supporting infotainment applications can be portable over different legacy operating systems providing unified programming interfaces. The majority of legacy operating systems support POSIX interfaces for application development. MOST is an automotive network standard for infotainment systems. Network Service defines the protocol stacks for MOST control data, which is essential to implement infotainment applications over MOST. In this paper, we suggest a POSIX-based Network Service so that we can utilize legacy device drivers and applications for automotive infotainment systems. We measure the performance of the POSIX-based Network Service and show that its overhead is not significant.

• Journal of the Korea Society of Computer and Information
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• v.21 no.1
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• pp.79-84
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• 2016

In this paper, we propose reliable message transmission scheme based on CoAP, considering the constrained feature of IoT device, such as low power, the limited memory size and low computing capacity. Recently, the various kinds of application protocol has been studied to support IoT environments. In particular, CoAP protocol was developed as application protocol for IoT at the IETF core WG. However, because CoAP protocol is deigned to be used in constrained node, this protocol uses UDP at transport layer. Thus, data loss may occur frequently in network congestion environments. The proposed scheme, in this paper, is to overcome the problem of frequent data loss with low overhead. Also it includes the function which is to minimize the data loss in sleep mode of IoT device.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.878-884
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• 2006

Grounding fault and short of the DC power supply systems are detected and protected by high-speed circuit breaker, linked breaking device, ground relay and fault selective device, all of which are installed and operated in substaions. however, there have been many cases in which the protective devices did not detect grounding of of the over head catenary systems on concrete support for an extended period of time. Such cases often cause severe damages to the supports with high grounding resistances. If grounding accidents occur repetitively, the earth current and the rise of earth potential can damage not only passenger and staff but also electric facilities and equipment, necessitating high cost and endeavor to restore. The following study points out various problems that can be occurred occur as a result of high impedance grounding accident, and proposes a new system which can protect and intercept them.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.05a
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• pp.145-148
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• 2011

As a futuristic construction model, building information model(BIM) based project management system(PMIS) and mobile PMIS have been showing visible sign. However, researches on the 3D BIM based PMIS using mobile device are hard to find, result from limitation of mobile device application(slow speed at huge BIM file, display size, and etc.) and undefined standard of business processes. Therefore, this research aims at studying feasibility of mobile BIM PMIS based on cloud computing as a business model. In case of applying mobile BIM PMIS, 3D drawings and integrated building informations are possible on mobile devices in real time. it would support increasing the productivity of project participants as designer, engineer, supervisor, and etc. Globally, BIM based PMIS and Mobile BIM system, cloud computing based mobile BIM simulator are in the concept or experimental phase, therefore it is possible to secure global leading technology of IT and construction merger in the mobile BIM.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.6
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• pp.1496-1504
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• 2007

The purpose of this paper, as a part of healthcare research, is to design and development Patient-aware System that will support EMR(Electronic Medical Record) in hospital. A mobile device-based system that can use database of existing EMR, replace existing paper-type chart, and identify patient fast and correctly was developed. To identify patient, RFID(Radio Frequency Identification) was used, and through interworking RFID and the system, it is possible to identify patient automatically. The developed system was tested in the test bed, and the possibility of faster diagnosis and treatment than existing paper-type chart was tested.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2003.03a
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• pp.409-414
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• 2003

A multi-span bridge model that is fixed in longitudinal direction at a single pier can be very vulnerable to the earthquake ground motion in longitudinal direction. If the seismic load exceeds the capacity of the pier, it can be severely damaged. However, such incident can be prevented if piers of movable support share the seismic load as setting up seismic load transmitting device. This study is performed to investigate seismic performance of continuous bridge model with seismic load transmitting devices which is proposed newly. It is found that continuous bridge model system with device is more effective about displacement control and seismic performance.

• IEMEK Journal of Embedded Systems and Applications
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• v.6 no.6
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• pp.393-400
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• 2011

Recently, demands of information devices are increasing as we can find so many information devices around us such as smartphone, MID(Mobile Internet Device), Tablet. These characteristics of information devices services should support soft real-time based time guaranteed multimedia services and control internet appliances. In this situation, soft real-time supported system should be developed to consider as a total aspect of hardware, kernel, middleware, application. But this paper will describe soft real-time supporting and evaluation methods for information device as an aspect of only kernel.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2019.05a
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• pp.351-354
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• 2019

The mobiAutoBot is a conceptual model of robotic process automation software with cognitive automation that can support mobile devices. The mobiAutoBot consists of two parts: mobiAutoBot controller and mobiAutoBot runner. The mobiAutoBot controller directs the job to the mobile device and performs monitoring and interworking. The mobiAutoBot runner installed on the mobile device performs the command execution. With the mobiAutoBot, you can build cost-effective robotic process automation capabilities and use it in a variety of applications, including mobile devices.