• Journal of information and communication convergence engineering
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• v.4 no.3
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• pp.118-122
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• 2006

In this paper, a sliding mode control method with uncertainty adaptation is proposed by introducing the virtual state. Because upper bound of the uncertainty is very difficult to know, we estimate this by using the simple adaptation law and design the sliding surface which has dynamic of nominal system. An optimal controller is used by nominal controller. And if initial values of the virtual state are chosen properly, the reaching phase is removed.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.332-332
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• 2000

In this paper, a novel sliding mode control with uncertainty adaptation is produced by introducing a virtual state. Because upper bounds of the uncertainty is difficult to know, we estimate these upper bound by using the simple adaptation law and design the novel sliding mode controller. The nominal controller is used the optimal controller to minimize cost function.

• Journal of information and communication convergence engineering
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• v.2 no.3
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• pp.198-201
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• 2004

In this paper, the discrete optimal control is made to have the robust property of Sliding mode controller. A augmented system with a virtual state is constructed for this objective and noble sliding surface is constructed based on this system. The sliding surface is the same as the optimal control trajectory in the original system. The states follow the optimal trajectory even if there exist uncertainties. The reaching phase problem of sliding mode control is disappear in this method.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.7
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• pp.1634-1640
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• 2010

In this paper, I studied the "Establishment of Fault Tolerant System" as well as the sensor and cylinder that are general components being used in automation equipments. I design a system that when the sensor breaks down on free flow conveyor, it will be converted to virtual sensor system mode by simulation, also I design IPC(Internal Pressure Cylinder), a basis of various applicable fault tolerant system by analyzing the changing of analog data according to the load of operation. With IPC and the increasing ability of developer, the Fault Tolerant System will be widely applied in the increasment of service time of cylinder, grease pouring time expection, fault recognition of cylinder and etc.

• Journal of Korean Society for Geospatial Information Science
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• v.12 no.1 s.28
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• pp.55-62
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• 2004

More recently, multiple reference based RTK GPS techniques(VRS ; Virtual Reference System) are becoming increasingly important for many precise GPS applications in many countries to overcome the constrained distance limitations of standard RTK systems. The precision of the position solutions of the rover receiver is closely connected with that of the corresponding virtual reference points(VRPs). The objective of this paper is to investigate the accuracy and performance of the VRPs on the test network have been made in post mode, and the overall analysis results were presented by comparing the solutions for the VRPs from the existing GPS reference station with the true values of the coordinates used to produce the observation data. The results show the reasonable accuracies of VRPs in the network area by using the VRS concept in post mode.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.22 no.51
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• pp.99-108
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• 1999

B-ISDN link dimensioning is often known as a difficult problem because of the characteristics of Asynchronous Transfer Mode(ATM) such as various Quality of Services of different service requirements, and the statistical multiplexing resulting from virtual path/virtual circuit connections. In this paper, we propose a nonlinear integer optimization model for dimensioning B-ISDN considering the statistical multiplexing effects of virtual path connections(VPCs) and the modularity of resources allocated to a transmission link. The algorithm based on the simultaneous linear approximation technique as well as some numerical results will be also presented.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.11a
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• pp.422-427
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• 2006

This paper presents force-feedback control performance of a haptic device in virtual environment of minimally invasive surgery(MIS). As a first step, based on an electrorheological(ER) fluid and spherical geometry, a new type of master device is developed and integrated with a virtual environment of MIS such as a surgical tool and human organ. The virtual object is then mathematically formulated by adopting the shape retaining chain linked(S-Chain) model. After evaluating reflection force, computational time, and compatibility with real time control, the virtual environment of MIS is formulated by interactivity with the ER haptic device in real space. Tracking control performances for virtual force trajectory are presented in time domain, and theirtrackingerrorsareevaluated.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.16 no.12 s.117
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• pp.1286-1293
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• 2006

This paper presents force-feedback control performance of a haptic device in virtual environment of minimally invasive surgery(MIS). As a first step, based on an electrorheological (ER) fluid and spherical geometry, a new type of master device is developed and integrated with a virtual environment of MIS such as a surgical tool and human organ. The virtual object is then mathematically formulated by adopting the shape retaining chain linked(S-chain) model. After evaluating reflection force, computational time, and compatibility with real time control, the virtual environment of MIS is formulated by interactivity with the ER haptic device in real space. Tracking control performances for virtual force trajectory are presented in time domain.

• Journal of Fashion Business
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• v.19 no.3
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• pp.130-143
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• 2015

By studying 3-D virtual human modeling, motion-capturing and clothing simulation for easier and safer work clothes development, this research aimed (1) to categorize heavy manufacturing work motions; (2) to generate a 3-D virtual male model and establish painting work motions within a 3-D virtual clothing simulation system through computerized body scanning and motion-capturing; and finally (3) to suggest simulated clothing images of painting work clothes developed based on virtual male avatar body measurements by implementing the work motions defined in the 3-D virtual clothing simulation system. For this, a male subject's body was 3-D scanned and also directly measured. The procedures to edit a 3-D virtual model required the total body shape to be 3-D scanned into a digital format, which was revised using 3-D Studio MAX and Maya rendering tools. In addition, heavy industry workers' work motions were observed and recorded by video camera at manufacturing sites and analyzed to categorize the painting work motions. This analysis resulted in 4 categories of motions: standing, bending, kneeling and walking. Besides, each work motion category was divided into more detailed motions according to sub-work posture factors: arm angle, arm direction, elbow bending angle, waist bending angle, waist bending direction and knee bending angle. Finally, the implementation of the painting work motions within the 3-D clothing simulation system presented the virtual painting work clothes images simulated in a dynamic mode.

• Proceedings of the KIEE Conference
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• 1998.07b
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• pp.744-746
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• 1998

In this paper, a new sliding mode observer is proposed by introducing a new sliding surface. The new sliding surface is defined based on the augmented error system with virtual error state. The new sliding mode observer have more degree of freedom than the existing VSS observer. It can have dynamics on the sliding surface.