• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.06a
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• pp.301-305
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• 1998

The Power measurement that can measure a single quantity does not smooth to install a system, and are not convenient to use. These measuring values are vary difficult for mutual operation and analyzing, and that have too many problems to compile measured databases. If each single measured values are mutual assist, correction and reform, the system will be able to be improved by minimizing differences between measure quantities and as making many different measurement system (Voltage, Current, Power and Resistor) is installed in one system. This study is useful to develope the power measurement system that is easier to analyze and management by database all of the parameter values because the power measurement system is able to be interbased with PC as requirement of industralization and information age.

• Structural Engineering and Mechanics
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• v.66 no.3
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• pp.369-377
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• 2018

In this article, buckling and free vibration of functionally graded (FG) nanobeams resting on elastic foundation are investigated by developing various higher order beam theories which capture shear deformation influences through the thickness of the beam without the need for shear correction factors. The elastic foundation is modeled as linear Winkler springs as well as Pasternak shear layer. The material properties of FG nanobeam are supposed to change gradually along the thickness through the Mori-Tanaka model. The small scale effect is taken into consideration based on nonlocal elasticity theory of Eringen. From Hamilton's principle, the nonlocal governing equations of motion are derived and then solved applying analytical solution. To verify the validity of the developed theories, the results of the present work are compared with those available in literature. The effects of shear deformation, elastic foundation, gradient index, nonlocal parameter and slenderness ratio on the buckling and free vibration behavior of FG nanobeams are studied.

• Journal of the Optical Society of Korea
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• v.16 no.3
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• pp.221-227
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• 2012

We propose optical proximity corrections (OPCs) for digital micromirror device (DMD)-based maskless lithography. A pattern writing scheme is analyzed and a theoretical model for obtaining the dose distribution profile and resulting structure is derived. By using simulation based on this model we were able to reduce the edge placement error (EPE) between the design width and the critical dimension (CD) of a fabricated photoresist, which enables improvement of the CD. Moreover, by experiments carried out with the parameter derived from the writing scheme, we minimized the corner-rounding effect by controlling light transmission to the corners of a feature by modulating a DMD.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05c
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• pp.194-199
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• 2003

Depth error correction effect for maladjusted stereo cameras with calibrated pixel distance parameter is presented. The proposed neural network technique is the real time computation method based theory of inter-node diffusion for searching the safety distances from the sudden appearance-objects during the work driving. The main steps of the distance computation using the theory of stereo vision like the eyes of man is following steps. One is the processing for finding the corresponding points of stereo images and the other is the interpolation processing of full image data from nonlinear image data of objects. All of them request much memory space and time. Therefore the most reliable neural-network algorithm is derived for real-time matching of objects, which is composed of a dynamic programming algorithm based on sequence matching techniques.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.482-484
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• 2003

GLI on boarded ADEOS-II satellite allows us to observe vegetation status in the two different resolutions simultaneously, because of thirty 1km resolution channels and six 250m resolution channels. There are four GLI land higher level products from these channels ; those are PGCP (Precise Geometric Correction Parameter), L2A_LC (TOA reflectance), ACLC (atmospheric corrected reflectance), and VGI (NDVI and EVI). This paper shows ADEOS-II GLI land data processing, and some of the latest results.

• Steel and Composite Structures
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• v.48 no.6
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• pp.709-725
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• 2023

This paper uses a new type of deformation theory to establish the free vibration and static buckling equations of nanoplates resting on two-parameter elastic foundations, in which the flexoelectric effect is taken into account. The proposed approach used in this work is not only simpler than other higher-order shear deformation theories but also does not need any shear correction coefficients to describe exactly the mechanical responses of structures. The reliability of the theory is verified by comparing the numerical results of this work with those of analytical solutions. The results show that the flexoelectric effect significantly changes the natural frequency and the critical buckling load of the nanoplate compared with the case of neglecting this effect, especially when the plate thickness changes and with some different boundary conditions. These are new results that have not been mentioned in any publications but are meaningful in engineering practice.

• Steel and Composite Structures
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• v.47 no.3
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• pp.383-393
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• 2023

Conventional reinforced concrete design codes assume ideal strain evolution in semi-deep beams with externally bonded fiber-reinforced polymer (EB-FRP) web strips. However, there is a strain interaction between internal stirrups and web strips, leading to a notable difference between code-based and experimental shear strengths. Current study provides an experiment-verified detailed numerical framework to assess the potential strain interaction under quasi-static monotonic load. Based on the observations, steel stirrups are effective only for low EB-FRP amounts and the over-strengthening of semi-deep beams prevents the stirrups from yielding, reducing its shear strength contribution. A notable difference is detected between the code-based and the study-based EB-FRP strain values, which is a function of the normalized FRP stress parameter. Semi-analytical relations are proposed to estimate the effective strain and stress of the components considering the potential strain interaction. For the sake of simplification, a linearized correction factor is proposed for the EB-FRP web strip strain, assuming its restraining effect as constant for all steel stirrup amounts.

• Journal of the Semiconductor & Display Technology
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• v.23 no.2
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• pp.23-27
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• 2024

Underwater images are typically degraded due to color distortion, light absorption, scattering, and noise from artificial light sources. Restoration of these images is an essential task in many underwater applications. In this paper, we propose a two-phase deep learning-based method, Underwater Deep Curve Estimation (UWDCE), designed to effectively enhance the quality of underwater images. The first phase involves a white balancing and color correction technique to compensate for color imbalances. The second phase introduces a novel deep learning model, UWDCE, to learn the mapping between the color-corrected image and its best-fitting curve parameter maps. The model operates iteratively, applying light-enhancement curves to achieve better contrast and maintain pixel values within a normalized range. The results demonstrate the effectiveness of our method, producing higher-quality images compared to state-of-the-art methods.

• Proceedings of the KSRS Conference
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• v.2
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• pp.756-759
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• 2006

The ocean tide loading (OTL) is an important factor for the GPS positioning, especially in the height direction. The shorter of the distance to the ocean, the larger of the error by the OTL. The influence will be changed when we measure in different place and the order of magnitude is from few centimeters to ten centimeters. In this study, more than ten kinds of the OTL models were collected and applied on the GPS static relative positioning in Taiwan. The GPS observations including five stations were obtained from Nov. 9, 2004 to Feb. 23, 2005 and we used the Bernese GPS software to execute the data processing. In this period, the average amplitudes of the 3-D coordinates are as follows: N is 0.4 cm, E is 0.7 cm, h is 1.8 cm at Kinmen station; N is 0.7 cm, E is 1.3 cm, h is 2.3 cm at Lanyu station; N is 0.5 cm, E is 0.7 cm, h is 2.0 cm at Matsu station; N is 0.6 cm, E is 0.6 cm, h is 2.0 cm at Penghu station and N is 0.5 cm, E is 1.2 cm, h is 1.7 cm at Hsinchu station. Moreover, we will analyze the advantage and disadvantage of every kind of the OTL models in different environments to offer some information to the GPS users and enhance the precision of the GPS positioning.

• Journal of Advanced Navigation Technology
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• v.21 no.5
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• pp.479-484
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• 2017

A Neustrelitz TEC model (NTCM) developed by Deutsches Zentrum $f{\ddot{u}}r$ Luft- und Raumfahrt (DLR) provides a better accuracy than the global positioning system (GPS) Klobuchar model for predicting ionospheric delay. The NTCM model accuracy is comparable to Galileo NeQuick model, and it has less computation time. The NTCM model uses F10.7 values as a parameter of solar activity function, while a NTCM-Broadcast (NTCM-BC) uses TEC values from a Klobuchar model. For this reason, a NTCM-BC model can be used for real-time ionosphere correction. In this paper, vertical ionospheric delay and GPS positioning errors in Korea by using a NTCM-BC ionosphere model from 2009 to 2014 are analyzed and compared with those of a Klobuchar model. In the 6-year statistics, the vertical ionospheric delay is reduced by 17.7 %, and horizontal and vertical positioning accuracies by the NTCM-BC model are improved by 25.6 % and 6.7 %, respectively, over the Klobuchar model.