• Nuclear Engineering and Technology
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• v.54 no.6
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• pp.2311-2320
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• 2022

The main outcomes of the experiments H2P6 performed in the thermal-hydraulics large-scale PANDA facility at PSI in the frame of the OECD/NEA HYMERES-2 project are presented in this article. The experiments of the H2P6 series consists of two PANDA tests characterized by the activation of three (H2P6_1) or one (H2P6_2) cooler(s) in an initially stratified and pressurized containment atmosphere. The initial stratification is defined by a helium-rich region located in the upper part of the vessel and a steam/air atmosphere in the lower part. The activation of the cooler(s) results i) in the condensation of the steam in the vicinity of the cooler(s), ii) the corresponding activation of large scale natural circulation currents in the vessel atmosphere, with the result of iii) the re-distribution and mixing of the Helium stratification initially located in the upper half of the vessel and iv) the continuous pressure decay. The initial helium layer represents hydrogen generated in a postulated severe accident. The main question to be answered by the experiments is whether or not the interaction of the different, localized cooler units would be important for the application of numerical methods. The paper describes the initial and boundary conditions and the experimental results of the H2P6 series with the suggestion of simple scaling laws for both experiments in terms of i) the temperature difference(s) across the cooler(s), ii) the transient steam and helium content and iii) the pressure decay in the vessel. The outcomes of this scaling indicate that the interaction between separate, closely localized units does not play a prominent role for the present experiments. It is therefore reasonable to model several units as one large component with equivalent heat transfer area and total water flow rate.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.46 no.4
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• pp.37-44
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• 2009

A novel phase-locked loop(PLL) architecture with resistance and capacitance scaling scheme has been proposed. The proposed PLL has three charge pumps. The effective capacitance and resistance of the loop filter can be scaled up/down according to the locking status by controlling the direction and magnitude of each charge pump current. This architecture makes it possible to have a narrow bandwidth and low resistance in the loop filter, which improves phase noise and reference spur characteristics. It has been fabricated with a 3.3V $0.35{\mu}m$ CMOS process. The measured locking time is $25{\mu}s$ with the measured phase noise of -105.37 dBc/Hz @1MHz and the reference spur of -50dBc at 851.2MHz output frequency

• Korean Journal of Cognitive Science
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• v.10 no.3
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• pp.17-28
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• 1999

Systematic distortions in perceived 3-D shape were obtained for elliptical and parabolic stereoscopic surfaces viewed at different distances under full and reduced cue conditions. In both conditions of Experiments 1 and 3, elliptical hemi-cylinders a appeared near veridical at the 45 cm viewing distances and flattened up to 74% of veridical at 135 cm. In Experiment 2, under full cue conditions, parabolic hemi-cylinders a appeared stretched to 118% of veridical at 45 cm, near veridical at 90 cm, and flattened to 85% of veridical at 135 cm. Under reduced cue conditions parabolas appeared flatter overall: veridical curvature was obtained at 45 cm viewing distance with flatness increasing to 68% of veridical at 135 cm. Results support a scaling explanation of perceived 3-D shape from disparity and rule out the alternative hypothesis that disparity curvature, an optical invariant, provides information for the direct perception of 3-D s shape.

• Journal of the Korean Mathematical Society
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• v.55 no.2
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• pp.373-390
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• 2018

In this paper we study the small-data scattering of the d dimensional fractional $Schr{\ddot{o}}dinger$ equations with d = 2, 3, $L{\acute{e}}vy$ index 1 < ${\alpha}$ < 2 and Hartree type nonlinearity $F(u)={\mu}({\mid}x{\mid}^{-{\gamma}}{\ast}{\mid}u{\mid}^2)u$ with max(${\alpha}$, ${\frac{2d}{2d-1}}$) < ${\gamma}{\leq}2$, ${\gamma}$ < d. This equation is scaling-critical in ${\dot{H}}^{s_c}$, $s_c={\frac{{\gamma}-{\alpha}}{2}}$. We show that the solution scatters in $H^{s,1}$ for any s > $s_c$, where $H^{s,1}$ is a space of Sobolev type taking in angular regularity with norm defined by ${\parallel}{\varphi}{\parallel}_{H^{s,1}}={\parallel}{\varphi}{\parallel}_{H^s}+{\parallel}{\nabla}_{{\mathbb{S}}{\varphi}}{\parallel}_{H^s}$. For this purpose we use the recently developed Strichartz estimate which is $L^2$-averaged on the unit sphere ${\mathbb{S}}^{d-1}$ and utilize $U^p-V^p$ space argument.

• Journal of Broadcast Engineering
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• v.9 no.1
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• pp.64-73
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• 2004

A robust watermarking algorithm is proposed for 3D mesh models. Watermark is inserted into the 2D image which is extracted from the target 3D model. Each Pixel value of the extracted 2D image represents a distance from the predefined reference points to the face of the given 3D model. This extracted image is defined as “range image” in this paper. Watermark is embedded into the range image. Then, watermarked 3D mesh is obtained by modifying vertices using the watermarked range Image. In extraction procedure, the original model is needed. After registration between the original and the watermarked models, two range images are extracted from each 3D model. From these images. embedded watermark is extracted. Experimental results show that the proposed algorithm is robust against the attacks such as rotation, translation, uniform scaling, mesh simplification, AWGN and quantization of vertex coordinates.

• Journal of the Korea Computer Graphics Society
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• v.17 no.1
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• pp.1-7
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• 2011

We present a new technique for constructing a sweep surface using two-parameter motion. Firstly, a new rational B-spline motion with two parameters is introduced, which is obtained by extending its orientation curve and scaling curve to surface counterparts. A sweep surface is then defined by a single vertex v under the two-parameter motion and allows to represent different u-directional iso-curves depending on parameter ${\upsilon}$. Efficient techniques for modeling and editing the surface are achieved by intuitively controlling the two-parameter motion. We demonstrate the effectiveness of our technique with experimental results on modeling and editing a 3D propeller model.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.2
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• pp.169-174
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• 2014

As a versatile processing method for nanoscale memory integration, laser-induced epitaxial growth is proposed for the fabrication of vertical Si channel (VSC) transistor. The fabricated VSC transistor with 80 nm gate length and 130 nm pillar diameter exhibited field effect mobility of $300cm^2/Vs$, which guarantees "device quality". In addition, we have shown that this VSC transistor provides memory operations with a memory window of 700 mV, and moreover, the memory window further increases by employing charge trap dielectrics in our VSC transistor. Our proposed processing method and device structure would provide a promising route for the further scaling of state-of-the-art memory technology.

• Korean Journal of Soil Science and Fertilizer
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• v.28 no.3
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• pp.227-232
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• 1995

The model equations including scaling factors to estimate the soil water characteristics curve(SWCC) without direct measurement of soil water tension were developed. Scaling were applied to a data set of soil water content, soil water tension, particle size distribution, and OM contents of the 134 soil samples with the 10 soil textural classes. The capability of the model equations was tested on another 205 soil samples. The parameter, ${\theta}^*$, of soil water contents was used by scale transformation as follows : ${\theta}^*=[{\theta}i-{\theta}(1.5MPa)]$/$[{\theta}(10KPa)-{\theta}(1.5MPa)]$ Using ${\theta}^*$ a model equation to estimate SWCC, which was applicable to all textural classes, was developed as follows: $H(0.1MPa)=0.13{\cdot}({\theta}^*)^{-2.04}$. Other model equations to estimate the water content at the soil water tension of 10KPa [${\theta}(10KPa)$] and 1.5MPa [${\theta}(1.5MPa)$], which are required to ${\theta}^*$ were developed by using scale factors of sand(S) and silt(Si) content and organic matter content(OM) as foilows : ${\theta}(10KPa)=26.80-3.99ln[S]+2.36{\sqrt{[Si]}}+2.88[OM]$ ($R=0.81^{**}$) ${\theta}(1.5KPa)=15.75-2.86ln[S]+0.55{\sqrt{[Si]}}+0.70[OM]$ ($R=0.76^{**}$) The measured and estimated values of ${\theta}(1/30MPa)$ on the 205 soil samples were highly correlated on 1 : 1 corresponding line with $R=0.85^{**}$.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.40-43
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• 1997

This paper presents a 3D object recognition method for generation of 3D environmental map or obstacle recognition of mobile robots. An active light source projects a stripe pattern of light onto the object surface, while the camera observes the projected pattern from its offset point. The system consists of a laser unit and a camera on a pan/tilt device. The line segment in 2D camera image implies an object surface plane. The scaling, filtering, edge extraction, object extraction and line thinning are used for the enhancement of the light stripe image. We can get faithful depth informations of the object surface from the line segment interpretation. The performance of the proposed method has demonstrated in detail through the experiments for varies type objects. Experimental results show that the method has a good position accuracy, effectively eliminates optical noises in the image, greatly reduces memory requirement, and also greatly cut down the image processing time for the 3D object recognition compared to the conventional object recognition.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.43.2-43.2
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• 2015

The massive limit of black holes (BHs) is observed as present day ten billion solar masses. We search for observational signatures of BHs that become extremely massive (EMBHs, 1-10 billion solar masses). I will report on the evolution of active galactic nuclei (AGNs) through the growth of BH mass and their dust emission strength. First, we measured 26 EMBH masses of quasars at 1