• Journal of KIISE:Computer Systems and Theory
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• v.32 no.1
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• pp.1-8
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• 2005

Image morphing to generate 2D transitions between images may be difficult even to express simple 3D transformations. In addition, previous view morphing method requires control points for postwarping, and is much affected by self- occlusion. This paper presents a new morphing algorithm that can generate automatically in-between scenes from un-calibrated images. Our algorithm rectifies input images based on the fundamental matrix, which is followed by linear interpolation with bilinear disparity map. In final, we generate in-between views by inverse mapping of homography between the rectified images. The proposed method nay be applied to photographs and drawings, because neither knowledge of 3D shape nor camera calibration, which is complex process generally, is required. The generated in-between views can be used in various application areas such as simulation system of virtual environment and image communication.

• Journal of the Korean Institute of Intelligent Systems
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• v.18 no.1
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• pp.122-126
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• 2008

Integrating a 3D solid modeler with a general purpose FEM code, an automatic stress intensity factor analysis system of the 3D crack problems has been developed. A geometry model, i.e. a solid containing one or several 3D cracks is defined. Several distributions of local node density are chosen, and then automatically superposed on one another over the geometry model by using the fuzzy knowledge processing. Nodes are generated and quadratic tetrahedral solid elements are generated by the Delaunay triangulation techniques. Finally, the complete finite element(FE) model generated, and a stress analysis is performed. This paper describes the methodologies to realize such functions, and demonstrates the validity of the present system.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.33 no.6
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• pp.21-30
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• 2005

The aerodynamic analysis of helicopter rotor airfoils was performed to generate the basic data for selection and distribution of airfoils at the helicopter rotor blade preliminary design phase.10 airfoils were chosen among the existing rotor airfoils, and the tabulated aerodynamic coefficients which are proper for the aerodynamic analysis using blade element theory were generated. Considering analysis cost, the simple mathematical models were chosen before the wind tunnel test to generate the aerodynamic characteristic curves($C_{l},C_{m},C_{d}$) in full AoA range($-180^{o}\sim180^{o}$) including the reverse flow region. The essential data necessary to the generation of the complete curves were obtained by using the IBLM(Interactive Boundary Layer Method). The generated aerodynamic characteristic curves agree with experimental results qualitatively. Finally, the aerodynamic characteristics of all 10 airfoils were compared and classified according to their own lift or moment characteristics.

• Journal of KIISE:Computer Systems and Theory
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• v.35 no.4
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• pp.172-177
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• 2008

In this paper, we design an authentication protocol based on Fuzzy Signature Vault Scheme using a light signature feature extraction method for user convenience and efficiency of electronic commerce. The signature is used broadly in electronic commerce because it is one of the simple and low-cost biometric items. However, signature has a problem that there are few low-cost and safe protocols. To solve this problem, we design a feature extraction method which is adequate for characters of signature and Fuzzy Vault Scheme. In addition, we design and analyze an efficient authentication protocol with some parameters used in this procedure. The followings are advantages when this protocol is applied to authentication procedure; 1) using convenient and low-cost signatures, 2) being possible to verify users with spending only about second for signature processing and authentication, 3) one time on transmission for sign-in and verification and 4) getting user authentication with secret value at the same time.

• Journal of KIISE:Computer Systems and Theory
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• v.35 no.8
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• pp.407-415
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• 2008

This paper presents novel segmentation and transition techniques for dancing motion synthesis. The segmentation method for dancing motions is based on Laban Movement Analysis (LMA). We assume a dance sequence as a set of small dancing motions. To segment a dancing motion is a subjective, psychological, and complex problem, so we extract the shape factor of LMA from a dance motion and observe shape's changes to find the boundaries of dance segments. We also introduce a transition method that meets constraints on the feet. This method that is based on a linear interpolation modifies the intermediate posture motion after analyzing footprint positions. The posture could be a key-frame between source motion and target motion on the transition. With the proposed techniques, it would be easy for multimedia applications to generate plausible dance motions.

• The Journal of the Korea Contents Association
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• v.10 no.2
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• pp.89-98
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• 2010

The enterprise system is becoming more complex and larger. With the changes of the times, the system is developing to object-oriented programming method(OOP). However, the same code inserts to the core class repetitiously in the OOP, that causes a decrease in productivity and a trouble of application of another requirement. To solve this weak point, we propose a weaving mechanism what applies to metadata and crosscutting concern. For a class optimization and an integration between different languages, we take the following way. This paper uses three ways, those are, metadata generation using reflection, transformation to Abstract Syntax Tree, and mapping through crosscutting information specified XML. Through the proposed theory, class optimization can be accomplished by solving a functional decentralization and a confusion of codes.

• Journal of KIISE:Computer Systems and Theory
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• v.35 no.12
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• pp.560-567
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• 2008

In this paper, we discuss a simple and straightforward binarization procedure which can generate black/white comics from the video frame image. Generally, the region of human's skin is colored white or light gray, while the dark region is filled with the irregular but regular patterns like hatching in most of the black/white comics. Note that it is not enough for simple threshold method to perform this work. Our procedure is decoupled into four processes. First, we use bilateral filter to suppress noise color variation and reserve boundaries. Then, we perform mean-shift segmentation for each similar colored pixels to be clustered. Third, the clustered regions are merged and extended by our region extension algorithm considering each color of their regions. Finally, we decide which pixels are on or off using by our dynamic binarization method based on the HSV color model. Our novel black/white cartooning procedure was so successful to render comic cuts from a well-known cinema in a resonable time and manual intervention.

• Journal of Korea Multimedia Society
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• v.13 no.5
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• pp.802-816
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• 2010

To create gesture from a new text input is an important problem in computer games and virtual reality. Recently, there is increasing interest in gesture stylization to imitate the gestures of celebrities, such as announcer. However, no attempt has been made so far to stylize a gestures using emotion such as happiness and sadness. Previous researches have not focused on real-time algorithm. In this paper, we present a system to automatically make gesture animation from SMS text and stylize the gesture from emotion. A key feature of this system is a real-time algorithm to combine gestures with emotion. Because the system's platform is a mobile phone, we distribute much works on the server and client. Therefore, the system guarantees real-time performance of 15 or more frames per second. At first, we extract words to express feelings and its corresponding gesture from Disney video and model the gesture statistically. And then, we introduce the theory of Laban Movement Analysis to combine gesture and emotion. In order to evaluate our system, we analyze user survey responses.

• Journal of KIISE:Software and Applications
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• v.28 no.11
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• pp.842-854
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• 2001

Today\`s first generation shopping agent is limited to comparing merchant offerings usually on price instead of their full range of attributes. Even in the full range comparison, there is not a good model which considers the overall features in the negotiation process. Therefore, the negotiation model needs to be extended to include negotiations over the more attributes. In this paper, we propose a negotiation model in the agent-mediated electronic commerce to negotiate over prices, product features, warranties and service policies based on utility theory and simple heuristics. We will describe a prototype agent-mediated electronic commerce framework called Pmart. This framework provides the software reuse and the extensibility based on the object-oriented technology. It is implemented on Windows-based platforms using Java and CORBA for the network transparency and platform independence.

• Journal of Korean Society of Transportation
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• v.25 no.2 s.95
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• pp.133-143
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• 2007

Previous studies on the transit assignment hardly show its achievement in research but have many limitations not only in theory but also in practice. This paper presents an integrated transit assignment model taking into account cost functions of multiple modes, such as auto, bus and subway, which represent an integrated network. An integrated transit network including cost functions and in-vehicle congestion needs to be developed. In addition, a link fare calculation model needs to be developed and applied to the model to calculate path travel costs. Based on these sub-models, a path-based traffic assignment model, which considers in-vehicle congestion and an integrated distance-based fare system in the integrated traffic network, is developed.