• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.4
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• pp.449-459
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• 2015

A lot of people were trapped in elevators without power supply when BLACK-OUT situation occurred in 2011. The telephone network of control room connected to the elevators had problem operating poorly. In this paper we propose an ICT based elevator emergency call device prototype system and evaluate the performance of the system. The proposed system quickly responds in emergency situation to guarantee passenger safety. For the goal, firstly the system tries to connect to a control room. If it fails the system attempts to call numbers for emergency contact and a rescue team sequentially. The system is designed to quickly support emergency contact as well. Finally, the information of elevator failure is rapidly transferred to the failure process device by the proposed system.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.38 no.6
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• pp.37-47
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• 2001

Due to the friction characteristics of pump, cylinder packing and passenger car, in the elevator actuated with hydraulic inverter-fed systems, there exist dead zones, which cannot be controlled by a PID controller. To overcome the drawbacks, in this paper, we propose a new hybrid control scheme, which switches the modes between a sliding mode controller and a PID controller. The proposed hybrid control scheme achieves an improved control performance by using both controllers. We first propose a design method of sliding mode controller for a hydraulic elevator system controlled by inverters, then fellowed by a design method of a hybrid sliding mode control scheme is proposed. The effectiveness of the proposed control scheme are shown by simulation results, which the proposed hybrid control method yields better control performance then the PID controlled scheme, not only in the zero-crossing speed region but also in the overall control region including steady-state region.

• Journal of the Korea Computer Industry Society
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• v.2 no.8
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• pp.1133-1138
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• 2001

In this paper, we implemented that MMT(Multimedia Terminal) demonstrates spot news, weather forecast, sports news and cultural news employed CDMA mobile communication networks. The MMT displays mobile pictures/joint pictures/on screen ad and to make known Bus stop or Mobile stations. The MMT gives driver's and passenger's safety and valuable information for one's use GPS satellites. We verified to make real time mobile picture transfer use of CDMA2000 1×(IS-95C) network and development the scheduler control each module. This system tested on vehicle that train and bus. MMT was implemented high reliability and stability by the embedded system. The mobile terminal shows reliable data transfer rate about 74Kbps on IS-95C.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.1227-1232
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• 2008

High-speed train of push-pull type called as G7 train has been developed and chosen as the model of KTX-II which will be operated on Honam Line nexr year. However, the EMU-type high-speed train appeared to be the recent trend that foreign markets have shown. Also, in the near future, a great number of new train sets are needed to accommodate the increased passengers in our country. Thus, development of the high-speed EMU was decided, planned, and started. In the development, included were almost all fundamental key technologies such as noise and vibration reduction in a passenger cabin, running characteristics, aerodynamic analysis, crashworthiness evaluation, EMI/EMC analysis, design of the cooling system for the propulsion control system, enhanced performance of transformer and switching converters, synchronous traction motor with permanent magnets, new design of front nose and ergonomic interiors, application of advanced information technology(IT) and smart sensors and the cost reduction of construction of railway bridges, etc. Each key technologies are carried out as sub-project independently but under the supervision of a project. The project will develop the high advanced level of technologies and provide necessary know-why's and support the team in charge of the development of the high-speed EMU, Hyundai Rotem Co. Ltd. The high-speed EMU will be successfully developed with the support of the project.

• Journal of Korea Multimedia Society
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• v.23 no.2
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• pp.255-261
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• 2020

As the accidents of cargo and passenger carrying ships occur, the stress faced by the vessel users is increasing. The risk factors for accident deterioration in remote marine area are stronger than those in road accidents, and therefore the need for safety control is greatly emphasized. To overcome such issue, a lot of effort has been made in terms of conducting research and development of the passengers and freights location tracking system. However, the inner bulkhead structures are made of aluminum/steel which is a difficult material to transfer location information through. This study aims to measure the receiving rate of LoRaWAN signal inside the aluminum/steel bulkhead structures with variation in reception strength and distance. The test was taken place at platforms with 6T and 8T enclosures to reflect the same conditions found in fishery patrol boats. The receiving rate of through-the-wall communication at 10M distance turned out to be 86% in case of using two 6T enclosures, and 73% in case of using one 8T enclosure. The result showed that the receiving rate was more affected by the thickness rather than the number of enclosures.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.38 no.1
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• pp.1-13
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• 2001

Due to the friction characteristics of cylinders and the rail of a passenger car, in the elevator actuated with hydraulic systems, there exist dead zones, which can not be controlled by a PID controller. To overcome the drawbacks, in this paper, we first try a hybrid controller which switches between a fuzzy logic controller and a PID controller. However, because the hybrid control scheme uses only a single type controller, except the switched layer, the high control performance can not be achieved. To solve this problem, we propose a new type fuzzy hybrid control scheme, which outputs of the output mixer arc controlled by a fuzzy logic. The hydraulic elevator system controlled by inverters has more then one switched layers due to the highly nonlinear characteristics. The proposed fuzzy hybrid control scheme achieves improved control performances by using both controllers with weighted outputs depend on the system status, to achieve improved control performances. The effectiveness of the proposed control scheme arc shown by simulation results, which the proposed fuzzy hybrid control method yields good control performance not only in the zero crossing speed region but also in the overall control region including steady-state region.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.1
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• pp.1-8
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• 2018

While the number of passengers using urban railroads is increasing day by day, the number of complaints from passengers is also increasing. In order to resolve problems caused by poor communication between urban railroad officials and passengers in this paper. An IOS application using the Internet of Things (IoT) technology is proposed for providing safety and comfort temperature service(s) and for taking prompt action(s) of passengers complaints. In this proposal system, the temperature & humidity sensors were placed in a suitable location within the train. At the same time, transferring measurements to the remote server, allowing passengers to request their desired temperature through the IOS Application. Like this based on the collected data, I suggest a system that urban railroad officials can control temperature & humidity of the train. The proposed system was implemented by the Gwangju Metro Line 1 to validate its effectiveness.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.9
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• pp.18-23
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• 2017

The shipyard quay process struggles to control workers and maintain a secure working environment because of the presence of at least 1,000 people. Therefore, safety accidents such as an explosion or a fire are likely to occur. With the recent increase in safety accidents at shipyards, the requirements for safety and process monitoring have been strengthened. Major shipyards are conducting researchto monitor the process in real time and to detect the work environment for safety. In this paper, we propose a safe and accurate evacuation route based on the information of the dangerous area and the user's location based on a mobile application to reduce the casualty accidents in the presence of many personnel in a concentrated area. To do this, we analyze the trend of the fire escape system on the ground building, compare various algorithms for escape route calculation, select appropriate algorithms for this study, and perform programming. A basic experiment was conducted to confirm the results. The proposed method is expected to be used in large ship construction sites, passenger ships and large public facilities to reduce accidents in the case of a safety accident.

• Journal of Navigation and Port Research
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• v.30 no.1 s.107
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• pp.9-15
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• 2006

At the adjacent sea area of Busan Central Wharf, a variety of vessels, such as middle-large passenger ships, small hugh speed crafts, container ships, cargo ships and working boats as well as small miscellaneous vessels are freely sailing comparatively without special rules and marine traffic control. In this research, we analyzed traffic stream and navigational characteristics cf main traffic route based on statistics and distribution of tracks by ship's type and tonnage cf the passing vessels after conducting marine traffic survey twice using exclusive software. We examined the traffic safety of the passing vessels by classifying the sea area by each function based on the analysis about this traffic situation, and analyzing the effect by designating 'Inner passage'. We also studied the plan for the effective rearrangement cf Central Wharf considering basically the traffic safety of arrival and departure in a point of view of navigators.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2005.10a
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• pp.103-109
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• 2005

At the adjacent sea area of Busan Central Wharf, a variety of vessels, such as middle-large passenger ships, small fast sailing ships, container ships, cargo ships and working ships as well as small miscellaneous vessels are freely sailing comparatively without special steering and sailing Rules and marine traffic control because exclusive wharfs in accord with their purpose and use have been arranged in each wharf. In this research, we analyzed traffic stream and navigational characteristics of main traffic route based on statistics and distribution of tracks by ship's type and tonnage of the passing vessels after conducting marine traffic survey twice using exclusive software by targeting the sea area during the period of time. We examined the traffic safety of the passing vessels by classifying the sea area by each function based on the analysis about this traffic situation, and analyzing the effect by designating 'Buknea passage'. We also studied the plan for the effective rearrangement of Central Wharf considering basically the traffic safety oif arrival and departure in a point if view of navigators.