• Journal of the Korea Safety Management & Science
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• v.10 no.2
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• pp.53-60
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• 2008

A test was conducted using two high density discharge lamps, the H2D and the structurally new H4D. They were tested for luminous illumination and luminous temperature in the day and night time. The test was conducted without crippling the performance of the H2D by adding a magnetic actuator, enabling it to move left to right, and up and down. By making these modifications we constructed a sample of the H4D. We compared the H2D and the H4D sample's luminous illumination and luminous temperature by using a photometer and a digital thermometer in the day and night time. We discovered that the H2D and H4D performed similarly from the data we gathered. Now we know the H4D has potential use and extensive research needs to be made to gather more detailed data.

• Journal of Institute of Control, Robotics and Systems
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• v.10 no.2
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• pp.153-163
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• 2004

The control objective in hard disk drives is to move head as fast as possible to target track and position the head over the center of target track in the presence of external disturbances. The external shock or disk clamping error in manufacturing process causes the disk center to deviate from the disk rotation center. The disk shift acts on the control system as disturbance and degrades severely the performance of disk drives. In this paper, we present a new controller that compensates for the periodic disturbances very fast. The disturbance compensator is arranged in parallel with the state feedback controller. To avoid the interference with the state feedback controller, the compensator creates compensation signal without the feedback of system output until steady state. The pulse type controller is included additionally for improving the transient performance due to initial state. Finally, in order to demonstrate the superior performance of the proposed compensator. we present some experimental results using a commercially available disk drive.

• The Journal of Korea Robotics Society
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• v.3 no.3
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• pp.203-211
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• 2008

This work proposes structure of spring backbone micro endoscope. For effective surgery in narrow and limited space, many manipulators are developing that different to existed structure. This device can move like elephant nose or snake unlike the existing robots. For this motion, a mechanism that uses spring backbone and wires has been developed. The new type endoscope that has Z axis motion for spring structure, therefore it has 3 degree of freedom, two rotations and one linear motion. And new kinematics for backbone structure is proposed using simple geographic analysis. The Jacobian and stiffness modeling are also derived. Exact actuator sizing is determined using stiffness model. Finally, the proposed kinematics are verified by simulation and experiments.

• Journal of Computing Science and Engineering
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• v.6 no.2
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• pp.168-177
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• 2012

The search for relevant and actionable information is a key to achieving clinical and research goals in biomedicine. Biomedical information exists in different forms: as text and illustrations in journal articles and other documents, in images stored in databases, and as patients' cases in electronic health records. This paper presents ways to move beyond conventional text-based searching of these resources, by combining text and visual features in search queries and document representation. A combination of techniques and tools from the fields of natural language processing, information retrieval, and content-based image retrieval allows the development of building blocks for advanced information services. Such services enable searching by textual as well as visual queries, and retrieving documents enriched by relevant images, charts, and other illustrations from the journal literature, patient records and image databases.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.1348-1356
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• 2011

The passenger side entrance door is very important system that make boarding and getting off the passengers. During the passenger door closing, there is some obstacles between door panels, passenger door can detect the obstacle and obstacle is remained between door panels, vehicle can no possible to move. But passenger door can not detect the obstacle if obstacle is too thin such as clothes and belts. So, anti-drag system is applied the to make detect these thin obstacle. Therefore, we survey the characteristic, function and its activation scenario of anti-drag system and present the passenger door system that latest applied anti-drag system that can be a help to make design.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.2830-2837
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• 2011

In this paper, a flexible track modeling of turnout was developed and dynamic characteristics of turnout rails were analyzed when a vehicle passed through the turnout. The flexible track modeling is effective to the stiffness and durability design of turnout, because it can capture the deformation and dynamic stress due to the collision of between wheels and rails when the vehicle move to the tongue rail. Also, a more accurate running safety can be obtained by considering the interaction between wheel and rail deformation. Solid finite elements were used for variable cross-sections of rails and the variation of rubber stiffness was modeled. The proposed flexible track modeling in this paper was verified to be valid by comparison with the experiment of the turnout system.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.3104-3110
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• 2011

This paper describes how to ensure safety of train by guaranteeing stable and continuous communication in RF-CBTC. CBTC System uses the wireless communication between onboard and wayside so that safety of wireless communication is the most important. Losing the position of train causes vital problem of train service. By losing the position of train, the other trains are blocked in the block and the train move by emergency mode so headway and safety cannot guaranteed. Therefore, safety is ensured by redundancy of wireless equipment. One of the ways to make redundancy is redundancy of equipment. However, the redundancy of equipment spends a lot of money to avoid interference in limited place like underground. Continuous communication is guaranteed by means of redundancy of wireless communication coverage to solve the problems even though one of the equipment is broken.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.1342-1347
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• 2011

Advantages of the deeply underground subway are underground space efficiency, high speed, decrease of noise and vibration. However, when fire occurs in the deeply underground subway station, large casualties are occurred like Daegu subway station fire due to the increase of evacuation distance. In this study, a numerical analysis was performed by using the fire and evacuation analysis program FDS+EVAC for smoke movement and evacuation in Beotigogae station among the deeply underground subway station. Heat release rate of carriage fire was set 10MW and the fire growth rate was ultrafast. As a result, the smoke move to the exit at 1085 second. The total evacuation time took 956 second.

• Journal of the Society of Naval Architects of Korea
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• v.49 no.4
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• pp.327-332
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• 2012

International Towing Tank Conference (ITTC) recommended verifying a ship's ability to move transversely at zero forward speed without altering heading by a crabbing test. In sea trial, all available propellers/rudders/thrusters should be used to find the maximum possible transverse speed. For estimating crabbing ability in the design stage, tests to estimate possible swaying force and yawing moment range using all available propellers/rudders/thrusters are conducted. By butterfly diagram, which compares possible swaying force and yawing moment range with external swaying force and yawing moment by wind, a ship's crabbing ability can be estimated. In this study, model tests of a cruise vessel equipped with bow thrusters and POD system were conducted to find out her crabbing ability in the design stage. To mimic quay condition, a model quay-wall was set in the towing tank.

• Proceedings of the Safety Management and Science Conference
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• 2010.11a
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• pp.81-91
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• 2010

Daily workers in construction sites rarely receive the benefit of systematic safety and health training as they are required to move from one construction site to another in response to the start, completion, and repetition of construction works. Also, small- to medium-sized construction sites often lack the capacity to train their workers. Therefore, as in the advanced countries, basic safety training system for construction workers should be conducted in the industrial-level, rather than in individual workplace-level, to make the training more effective. By doing so, only workers with the basic safety training will be able to engage in construction works. Consequently, accidents in the construction industry will decrease, as workers themselves who are at the forefront of the construction worksites are empowered to play the central role in accident prevention activities.