• Journal of Institute of Control, Robotics and Systems
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• v.11 no.8
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• pp.678-687
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• 2005

This paper describes a relative localization algorithm using odometry data and consecutive local maps. The purpose of this paper is the odometry error correction using the area matching of two consecutive local maps. The local map is built up using a sensor module with dual laser beams and USB camera. The range data form the sensor module is measured using the structured lighting technique (active stereo method). The advantage in using the sensor module is to be able to get a local map at once within the camera view angle. With this advantage, we propose the AVS (Aligned View Sector) matching algorithm for. correction of the pose error (translational and rotational error). In order to evaluate the proposed algorithm, experiments are performed in real environment.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1994.04a
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• pp.42-48
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• 1994

This paper presents the navigation method for a mobile robot which uses a single camera and fluorescent lamp as a guide mark, projected on a convex mirror. The current position and heading direction of the mobile robot are obtained from the image of the guide mark. While the mobile robot travels to a goal position, the current position and heading direction of the mobile robot are updated continuously and the desired path and actual moving path are displayed on the monitor screen in real time. This proposed method eliminates the need to rotate the camera to track the guide mark, since a panoramic view of the surrounding area is available from the convex mirror, and natural guide marks such as usual florescent lamp on the ceiling or door frame can be used for navigation.

• Journal of IKEEE
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• v.4 no.2 s.7
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• pp.281-287
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• 2000

A mobile ad-hoc network is composed of only mobile nodes, which are distributed dynamically, without any wired backbone or centralized entities. Since the existing works on ad-hoc routing protocol are mostly biased toward a military application, we need a new routing scheme for a support of multimedia services in mobile ad-hoc networks. Therefore, we propose a novel scheme that can support a variety of traffic attributes and can be applicable to high-speed and multimedia data services in mobile ad-hoc networks by using adaptive transmission power level. As a result of simulation, the proposed scheme has better performance than conventional method, which is performed with uniform transmission power level, in view of route query delay time.

• ETRI Journal
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• v.19 no.3
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• pp.98-115
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• 1997

The architecture of the CDMA mobile system (CMS) is developed based on three function groups - service resource, service control, and service management groups. In this paper, the CMS architecture is discussed from the point of view of implementing these functions. The variable length packets are used for transmission. The synchronization clock signals are derived form the GPS receiver. The open loop and closed loop techniques are used for the power control. The internationally accepted signaling and network protocols are employed. The call control for the primary services in designed to provide efficient mobile telecommunication services. The softer handoff is implemented in one card. The mobile assisted handoff and the network assisted handoff are employed in the soft and hard handoffs. The authentication is based on the secret data which includes random numbers. The management functions, which include the location management, resource management, cell boundary management and OAM management, are implemented to warrant the system efficiency, maximum capacity and high reliability. The architecture ensures that the CMS is flexible and expandable to provide subscribers with economic and efficient system configuration. The dynamic power control, adaptive channel allocation. and dynamic cell boundary management are recommended for future work.

• Journal of the Korean Society of Industry Convergence
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• v.24 no.3
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• pp.301-306
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• 2021

In this paper, we propose a modified back-stepping control method in view of the dynamic model of mobile manipulator has the nonholonomic constraints, these constraints should be considered to design a tracking controller for the mobile manipulator. The conventional back-stepping controller includes the dynamics and kinematics of the mobile robot systems. and the modified adaptive back0stepping method is applied to constructing the controller. The proposed controller can realize the tracking trajectory of the reference path. The efficiency and robustness of this control method is demonstrated by the simulation.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.173-176
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• 2013

This paper's questions, and an automatic scoring system written in HTML, and XML-based system that is at issue, the issue questions in a convenient offline automatically how to register, Easy to manage questions of issues, questions and problems of merging the PC and the mobile device in a place that can be obtained without taking the test system study. Server systems, and real-time registration questions merging problem, such as difficulty adjusting to the test required to build the system. Clients communicate with the server using the mobile device and the PC is required to take the exam in the View application, and responses are sent for treatment research.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2014.10a
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• pp.370-372
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• 2014

This study questions, and an automatic scoring system written in HTML, and XML-based system that is at issue, the issue questions in a convenient offline automatically how to register, Easy to manage questions of issues, questions and problems of merging the PC and the mobile device in a place that can be obtained without taking the test system study. Server systems, and real-time registration questions merging problem, such as difficulty adjusting to the test required to build the system. Clients communicate with the server using the mobile device and the PC is required to take the exam in the View application, and responses are sent for treatment research.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.13
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• pp.69-81
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• 2000

Under the co-sponsorship of UNIDROIT and I.C.A.O., a preliminary draft Convention on International Interests in Mobile Equipment and a preliminary draft Protocol on Matters Specific to Aircraft Equipment has been prepared. The purpose of the Convention is to provide for the creation and effect of a new international interest in mobile equipment. The Convention's approach is quite novel in that it purports to create an international interest based upon the convention itself. The Convention is intended to be supplemented by Protocols, each of is intended to provide equipment-specific rules necessary to adapt the rules of the Convention to fit the special pattern of financing for different categories of equipment. To date, two sessions of governmental experts were held in Rome and Montreal. Korean delegations attended the two sessions. One of the members of the Korean delegation published a report on the first session. He expressed his objection to the so called self-help remedy contemplated by the current preliminary draft of the Convention which enables the holder of a security interest to repossess and dispose of the subject of the security interest by private sale rather than public auction on the occurrence of an event of default of the debtor. His view is based upon his understanding that under Korean law, the only remedy available to the holder of a security interest in mobile equipment, such as an airplane, is to apply to the competent court for a public auction. In my view, his understanding is not quite correct and is inconsistent with the current practice in Korea. Under Korean law, the parties' agreement for private sale is in principle valid unless there is an interested party who has acquired a security interest after the creation of the prior security interest or a creditor who has caused the subject of the security interest to be attached by a competent court. In this article, I discuss the current Korean law and practice relating to the enforcement of security interests by private sale in more detail.

• 제어로봇시스템학회:학술대회논문집
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• 1988.10b
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• pp.810-815
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• 1988

This paper presents a mobile robot that travels employing visual information. The mobile robot is equipped solely with a TV camera as a sensor, and views from the TV camera are transferred to a separately installed micro computer through an image acquisition device. An acquired image of a view is processed there and the information necessary for travel is yielded. Instructions based on the information are then sent from the micro computer to the mobile robot, which causes the mobile robot next action. Among several application programs that have already been developed for the mobile robot other than the entire control program, this paper focuses its attention on the travelling control of the mobile robot in a model environment with obstructions as well as an overview of the whole system. The behaviour the present mobile robot takes when it travels among obstructions was investigated by an experiment, and satisfactory results were obtained.

• 한국정보통신설비학회:학술대회논문집
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• 2008.08a
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• pp.97-101
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• 2008

Voice over IP is a telephone service which sends and receives the voices through the Internet. Because the infrastructure of wireless and mobile communication networks such as 3G, Wi-Fi and WiMAX has expanded, the study about Mobile VoIP, which provides the voice service from wireless network, has been actively in progress. Since Rei 6 HSPA in 3GPP and Rev A lxEVDO in 3GPP2, VoIP through the data channel is more efficient than circuit switch. It is predicted that VoIP over 4G will be more effective and 4G mobile VoIP business will be vitalized in the future. In addition, there are businesses which offer VoWLAN by using software such as Skype and Fring. They provide services which cheapen the price of international calls and long distance calls. This paper will present the Korean and other countries' mobile VoIP trends, its classification along the network connection, the study on techniques, and conditions of mobile VoIP. It also will be described a view of terminal convergence and service convergence.