• East Asian mathematical journal
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• 제24권2호
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• pp.177-186
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• 2008

In this paper, we introduce and study a new class of system of parametric general quasivariational-like inequalities. Using $\eta$-subdifferential and $\eta$-proximal mappings of proper functionals in Hilbert spaces, we prove the equivalence between the system of parametric general quasivariational-like inequalities and a xed point problem and construct two iterative algorithms. A few existence and uniqueness results as well as the sensitivity analysis of solutions are also established for the system of parametric general quasivariational-like inequalities, and some convergence results of iterative sequence generated by the algorithms are proved. Our results extend a few known results in the literature.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.1012-1016
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• 1991

An effective visual servo control system for robotic manipulators based on neural networks is proposed. For this control system, firstly, one neural network is used to learn the mapping relationship between the robot's joint space and the video image space. However, in the proposed control scheme, this network is not used in itself, but its first and second derivatives are used to generate servo commands for the robot. Secondly, an adaptive Adaline network is used to identify the dynamics of the robot and also to generate the proper torque commands. Computer simulation has been performed indicating its superior performance. As far as the authors know, this is the first time attempt of the use of neural networks for a visual servo control of robots that compensates for their changing dynamics.

• 디지털산업정보학회논문지
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• 제12권1호
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• pp.27-33
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• 2016

In this study we propose a method for 3D landform reconstruction and object modeling method by generating contour lines on the map using a depth sensor which abstracts characteristics of geological layers from the depth map. Unlike the common visual camera, the depth-sensor is not affected by the intensity of illumination, and therefore a more robust contour and object can be extracted. The algorithm suggested in this paper first abstracts the characteristics of each geological layer from the depth map image and rearranges it into the proper order, then creates contour lines using the Bezier curve. Using the created contour lines, 3D images are reconstructed through rendering by mapping RGB images of the visual camera. Experimental results show that the proposed method using depth sensor can reconstruct contour map and 3D modeling in real-time. The generation of the contours with depth data is more efficient and economical in terms of the quality and accuracy.

• Journal of Welding and Joining
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• 제33권1호
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• pp.30-34
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• 2015

Residual stresses are inherently introduced into the engineering components during manufacturing including rolling, forging, bending and welding processes. Excessive residual stresses are known to be detrimental to the proper integrity and performance of components. Neutron diffraction has become a well-established technique for the determination of residual stresses in welds. The deep penetration capability of neutrons into most metallic materials makes neutron diffraction a powerful tool for the residual stress measurements through the thickness of the weld specimen. Furthermore, the unique volume-averaged bulk characteristic of the scattering beam and mapping capability in three dimensions is suitable for the engineering purpose. In this presentation, the neutron diffraction measurements of the residual stresses will be introduced and measurement results will highlighted in thick weld plates.

• Journal of Ship and Ocean Technology
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• 제5권3호
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• pp.27-35
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• 2001

In this research, hybrid method with case-based reasoning and rule-based reasoning is applied. Using case-based reasoning, design experts'experience and know-how are effectively represented in order to obtain a proper configuration of midship section in the initial ship design stage. Since there is not sufficient domain knowledge available to us, traditional case-adaptation algorithms cannot be applied to our problem, i.e., creating the configuration of midship section. Thus, new case-adaptation algorithms not requiring any domain knowledge are developed antral applied to our problem. Using the knowledge representation of DnV rules, rule-based reasoning can perform deductive inference in order to obtain the scantling of midship section efficiently. The results from the case-based reasoning and the rule-based reasoning are examined by comparing the results with various conventional methods. And the reasonability of our results is verified by comparing the results wish actual values from parent ship.

• 전자공학회논문지B
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• 제29B권10호
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• pp.37-45
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• 1992

For a precise manipulator control in the presence of environmental uncertainties, it has long been recognized that the robot should be controlled in a task-referenced space. In this respect, an effective visual servo control system for robot manipulators based on neural networks is proposed. In the proposed control system, a Backpropagation neural network is used first to learn the mapping relationship between the robot's joint space and the video image space. However, in the real control loop, this network is not used in itself, but its first and second derivatives are used to generate servo commands for the robot. Second, and Adaline neural network is used to identify the approximately linear dynamics of the robot and also to generate the proper joint torque commands. Computer simulation has been performed demonstrating the proposed method's superior performance. Futrhermore, the proposed scheme can be effectively utilized in a robot skill acquisition system where the robot can be taught by watching a human behavioral task.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2003년도 암반역학위원회 학술세미나 논문집
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• pp.165-193
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• 2003

The Han River tunnel connecting Yoido and Mapo was constructed as a part of the Seoul subway line No.5, which is 52 km long, to improve the traffic conditions of Seoul. It is constructed 15.6∼30m below the river floor. It Is the first under-river tunnel in Korea with the length of 1,288m. Geological conditions of the ground under the Han River were more complex and irregular than expected at the design stage, because there were several faults, fracture zones and slickensided joints coated with graphite. It was thus indispensable to estimate the ground condition of the tunnel face to apply proper excavation and reinforcement methods. Advance borings and face mappings were performed before excavation to improve constructional efficiency and excavation stability.

• 한국인쇄학회지
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• 제18권2호
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• pp.69-82
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• 2000

Recently, as the prepress mainstream is changed to the digital workflow, various digital proofing systems such as high price dye sublimation printers and low price ink jet printers are widely used in printing industry. CRT monitors are also often used as a soft proofing device. However, it is very difficult to match the color image displayed on CRT monitors to the actual images printed on papers, because the color space of CRT monitors is RGB color system, and it is different with the CMY color system of the printing devices. Therefore, proper color compensations are needed to match the colors between hard-copy proofs on the printing device and soft copy proofs on CRT monitors. This paper shows the LUT and gamut mapping method considering the printing characteristics of output device is useful for the compensation.

• 한국자동차공학회논문집
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• 제2권6호
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• pp.57-65
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• 1994

A collision-free path planning algorithm between an articulated robot and polyhedral obstacles using configuration space is presented. In configuration space, a robot is treated as a point and obstacles are treated as grown forbidden regions. Hence path planning problem is transformed into moving a point from start position to goal position without entering forbidden regions. For mapping to 3D joint space, slice projection method is used for first revolute joint and inverse kinematics is used for second and third revolute joint considering kinematic characteristics of industrial robot. Also, three projected 2D joint spaces are used in search of collision-free path. A proper example is provided to illustrate the proposed algorithm.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2004년도 Korea-Russia Joint Conference on Geometics
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• pp.73-81
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• 2004

National Geographic Information Institute (NGII) in Korea, through National Geographic Information System (NGIS) Program, has prepared to generate and disseminate digital elevation data for Korea. This is a pilot research to propose a policy for generation, maintenance, and supply of Korea Digital Elevation Data (KDED). Customer demands for accuracy and resolution of DEM was surveyed through questionnaire. In order to investigate the quality, the technical efficiency and the production cost, a tentative DEM in a small test site was generated based on digital topographic maps (original paper map scale 1 :5,000), analytical plotter, and LIDAR. Accuracy standard for KDED was derived based on source data and generation methods. As results of this research, we recommend uniformly spaced grid model for KDED. Its preferable grid space is 5m in urban and its vicinity; and 10m in field and mountainous area. LIDAR has been valuated as a proper KDED generation method fulfilling customers demand for the accuracy.