• Journal of Institute of Control, Robotics and Systems
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• v.15 no.3
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• pp.315-322
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• 2009

This paper explains a control and navigation algorithm of a 6-DOF gait rehabilitation robot, which can allow a patient to navigate in virtual reality (VR) by upper and lower limbs interactions. In gait rehabilitation robots, one of the important concerns is not only to follow the robot motions passively, but also to allow the patient to walk by his/her intention. Thus, this robot allows automatic walking velocity update by estimating interaction torques between the human and the upper limb device, and synchronizing the upper limb device to the lower limb device. In addition, the upper limb device acts as a user-friendly input device for navigating in virtual reality. By pushing the switches located at the right and left handles of the upper limb device, a patient is able to do turning motions during navigation in virtual reality. Through experimental results of a healthy subject, we showed that rehabilitation training can be more effectively combined to virtual environments with upper and lower limb connections. The suggested navigation scheme for gait rehabilitation robot will allow various and effective rehabilitation training modes.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.05a
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• pp.327-330
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• 2012

In the rapid growth of cities, road has heavy traffic and many buildings are under constructions. These kinds of environments make more difficulty for a person who is visually handicapped to walk comfortable. To alleviate the problem, we introduce Android based Portable Navigation System to help walking for Visually Impaired Person. It follows, service center give instant real time monitoring to visually impaired person for their convenient by this system. Android based Portable Navigation System has GPS, Camera, Audio and WI-FI(wireless fidelity) available. It means that GPS location and Camera image information can be sent to service center by WI-FI network. To be specific, transmitted GPS location information enables service center to figure out the visually impaired person's whereabouts and mark the location on the map. By delivered Camera image information, service center monitors the visually impaired person's view. Also, they can offer live guidance to visually impaired person by equipped Audio with live talking. To sum up, Android based Portable Navigation System is a specialized navigation system that gives practical effect to realize more comfortable walking for visually impaired person.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.12
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• pp.2702-2707
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• 2012

In the rapid growth of cities, road has heavy traffic and many buildings are under constructions. These kinds of environments make more difficulty for a person who is visually handicapped to walk comfortable. To alleviate the problem, we introduce Navigation System to help walking for Visually Impaired Person. It follows, service center give instant real time monitoring to visually impaired person for their convenient by this system. This Navigation System has GPS, Camera, Audio and Wi-Fi(wireless fidelity) available. It means that GPS location and Camera image information can be sent to service center by Wi-Fi network. To be specific, transmitted GPS location information enables service center to figure out the visually impaired person's whereabouts and mark the location on the map. By delivered Camera image information, service center monitors the visually impaired person's view. Also, they can offer live guidance to visually impaired person by equipped Audio with live talking. To sum up, Android based Portable Navigation System is a specialized navigation system that gives practical effect to realize more comfortable walking for visually impaired person.

• Korean Journal of Computational Design and Engineering
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• v.12 no.1
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• pp.15-26
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• 2007

We have developed a method that enables a user to better understand and enjoy the contents of 3D digital archives, thereby enhancing the user's experience. The system's interactive interface, built using virtual reality technology, enables the user to "walk through" the archives, comparing two or the same content at different points in time. For example, a user can compare the proposed design for a building with the actual building and can compare the states of restoration of a cultural heritage site over time. This ability to perform multilateral comparisons enables the user to clarify the relationship between contents, the influence of one content on another, and the causal relationship between contents. Testing of a prototype system for a 3D digital archive of cultural heritage sites showed that it worked smoothly and that the users could easily operate the navigation system.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.4 s.97
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• pp.138-147
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• 1999

For autonomous navigation, a legged robot should be able to walk over irregular terrain and adapt itself to variation of supporting surface. Walking through slope is one of the typical tasks for such case. Robot needs not only to change foot trajectory but also to adjust its configuration to the slope angle for maintaining stability against gravity. This paper suggests such adaptation algorithm for stable walking which uses feedback of reaction forces at feet. Adjusting algorithm of foot trajectory was studied with the estimated angel of slope without visual feedback. A concept of virtual slope angle was introduced to adjust body configuration against slope change of the supporting terrain. Regeneration of foot trajectory also used this concept for maintaining its stable walking against unexpected landing point.

• Journal of Advanced Navigation Technology
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• v.15 no.4
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• pp.632-639
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• 2011

Searching distributed resource efficiently is very important in distributed computing, cloud computing environment. Distributed resource searching may have system overheads and take much time in proportion to the searching number, because distributed resource searching has to circuit many peers for searching information. The open-source community project JXTA defines an open set of standard protocols for ad hoc, pervasive, peer-to-peer computing as a common platform for developing a wide variety of decentralized network applications. In this paper, we proposed peer search algorithm based on JXTA-Sim. original JXTA peer searching algorithm selected a loosely-consistent DHT. Our Lookup algorithm decreases message number of WALK_LOOKUP and reduce the network system overload, and we make a result of same performance both original algorithm and our proposed algorithm.

• Journal of the Korean Institute of Intelligent Systems
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• v.21 no.6
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• pp.692-697
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• 2011

There are many researches to develop robots that improve its mobility to adapt in various uneven environments. In the paper, a hybrid mobile robot that can dock with the other robot and transforms between wheeled robot and legged robot is proposed. The hybrid mobile robot platform has docking device with a peg and a cup module. In addition, the robot is possible to walk and drive according to condition of the road. A navigation algorithm of the hybrid mobile robot is proposed to improve the mobility of robots using docking algorithm based on image processing on the broken road and uneven terrain. The proposed method recognizes road condition through PSD sensor attached in front and bottom of the robot and selects an appropriate navigation method according to terrain surface. The proposed docking and navigation methods are verified through experiments using hybrid mobile robots.

• Journal of Navigation and Port Research
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• v.28 no.5
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• pp.455-462
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• 2004

Recently, according to the increase of personal income and enough time to spare. people demand the expansion of waterfront space in the city and the development of waterfront's possibility. In this study, which takes a place of the Jeol-young seaside park in young-do investigated for the user's pattern of seaside park located in coastal area And analyzed into user's attributes and a feeling of satisfaction The results of this study were as follows ： 1) The Jeol-young seaside park is facilitated for taking a walk. It also tends to be preferred for the ocean view, jogging, relaxation, and so on 2) The Jeol-young seaside park has to be ensured with its safety and convenience of esplanade. In order to provide the user's high satisfaction, more facilities of expansion and parking area are demanded to be developed.

• Journal of Navigation and Port Research
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• v.26 no.5
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• pp.563-569
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• 2002

To overcome the weaknesses of conventional finite difference model in pollutant dispersion modelling, the particle tracking method is used. In this study, a three dimensional particle tracking model which can be used in Princeton Ocean Model was developed and verified through the various numerical tests. Usability of the model was also confirmed through the ocean outfall modelling in Tampa Bay, Florida. As it is expected, random walk model showed the less dispersion in a range compared to the conventional finite difference model and its reason is estimated due to an error from numerical diffusion which the conventional model holds. This newly developed model is expected to be used in various ocean dispersion modelling.

• Journal of the Korean Institute of Navigation
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• v.16 no.1
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• pp.94-97
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• 1992

In this paper, the individual number of the future has depended not only upon the present individual number but upon the present individual age, considering the stochastic process model of individual number when the life span of each individual number and the individual age as a set, this becomes a Markovian. Therefore, in this paper the individual is treated as invariable, without depending upon the whole record of each individual since its birth. As a result, suppose {N(t), t>0} be a counting process and also suppose $Z_n$ denote the life span between the (n-1)st and the nth event of this process, (n{$geq}1$) : that is, when the first individual is established at n=1(time, 0), the Z$Z_n$ at time nth individual breaks, down. Random walk $Z_n$ is $Z_n=X_1+X_2+{\cdots}{\cdots}+X_A, Z_0=0$ So, fixed time t, the stochastic model is made up as follows ; A) Recurrence (Regeneration)number between(0.t) $N_t=max{n ; Z_n{\leq}t}$ B) Forwardrecurrence time(Excess life) $T^-I_t=Z_{Nt+1}-t$ C) Backward recurrence time(Current life) $T^-_t=t-Z_{Nt}$