• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.35 no.1
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• pp.1-10
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• 2022

Two-dimensional materials have shown a great promise for the next-generation electronic materials due to their unique optical, physical, and chemical properties that are distinct from their bulk counterparts. Their atomic-level thickness, the feature for flexible tenability, and exposed huge surface allow various approaches for high-performance nanoscale devices. Especially, this review highlights the recent progress on two-dimensional dielectric nanosheets, which are obtained by cheap and massproducible solution-based exfoliation process, accompanied by the preparation methods, various deposition methods, and the characteristics of devices using a dielectric nanosheet thin films. We also present a perspective on the advantages offered by this two-dimensional dielectric nanosheets for the upcoming future nanoelectonics.

• Journal of the Korea Convergence Society
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• v.4 no.4
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• pp.21-29
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• 2013

Two-dimensional QR Code has improved greatly the limits on the capacity, size, direction of the one-dimensional bar code. And it has the capacity of compressing and storing the massive amount of data and is widely used in many applications. Recently, the two-dimensional QR Code has been spread rapidly because of introducing the smart phones and increasing the amount of using them. However, there is little documentations about decoding the QR Code in which can store the large amount of information. In this paper, therefore, we present specific processing procedures and algorithms on decoding the two-dimensional QR Code and then make us understand their decoding process by explaining some examples.

• Journal of Electrical Engineering and Technology
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• v.11 no.6
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• pp.1684-1692
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• 2016

In order to adapt the fast dynamic performances of Buck DC/DC converter, and reduce the influence on converter performance owing to uncertain factors such as the disturbances of parameters and load, a control strategy based on two-dimensional hybrid cloud model is proposed. Firstly, two cloud models corresponding to the specific control inputs are determined by maximum determination approach, respectively, and then a control rule decided by the two cloud models is selected by a rule selector, finally, according to the reasoning structure of the rule, the control increment is calculated out by a two-dimensional hybrid cloud decision module. Both the simulation and experiment results show that the strategy can dramatically improve the dynamic performances of the converter, and enhance the adaptive ability to resist the random disturbances, and its control effect is superior to that of the current-mode control.

• Journal of architectural history
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• v.3 no.2 s.6
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• pp.125-141
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• 1994

Alois Riegl's aesthetic theory of visual perception provided one of important conceptual backgrounds for Vienna Art Nouveau architecture. Riegls theory of visual perception consists of geometric style and two-dimensional transformation. Riegl's theory of geometric style is based on the modern aesthetic theory of abstraction, which says that the artistic perfection can be obtained not from a direct imitation of natural objects, but from an abstract transformation of them. Riegl's theory of two-dimensional transformation, on the other hand, aims at obtaining artistic perfection by disintegrating volumetric conditions of natural things into planes and combining the planes thus obtained into another new world of art. These two theories of Alois Rigl's provided an important aesthetical background for the design strategy of 'abstract ornamentaion of two-dimension' in Vienna Art Nouveau architecture. This paper is to review the basic concept of Alois Rigl's theory of geometric style and two-dimensional transformation.

• Journal of Information Processing Systems
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• v.12 no.3
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• pp.381-391
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• 2016

The Joint Bayesian (JB) method has been used in most state-of-the-art methods for face verification. However, since the publication of the original JB method in 2012, no improved verification method has been proposed. A lot of studies on face verification have been focused on extracting good features to improve the performance in the challenging Labeled Faces in the Wild (LFW) database. In this paper, we propose an improved version of the JB method, called the two-dimensional Joint Bayesian (2D-JB) method. It is very simple but effective in both the training and test phases. We separated two symmetric terms from the three terms of the JB log likelihood ratio function. Using the two terms as a two-dimensional vector, we learned a decision line to classify same and not-same cases. Our experimental results show that the proposed 2D-JB method significantly outperforms the original JB method by more than 1% in the LFW database.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1755-1760
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• 2004

The holographic velocimetry system has a significant potential for the measurements of three dimensional velocities of particles. In this study, orthogonal two-side holography system was developed to obtain three dimensional velocities and sizes of spray droplets. To get high quality of reconstructed images, singe-exposure holography at two time moments and two orthogonal sides was adopted instead of multi-exposure, single-side holography. From three dimensional positions of droplets determined by reconstruction and image processing system, the three dimensional velocities and sizes of each droplet was extracted using the PTV algorithm. To determine the position of particles in the optical axis, a new focusing parameter was introduced based on the correlation between two droplet images at the same distance. The measured results by holography system were compared with those by the PDPA.

• Journal of the Ergonomics Society of Korea
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• v.8 no.2
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• pp.35-41
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• 1989

In this paper a new method is proposed to create 3-dimensional coordinate values from two 2- dimensional images (side and front image of objects) using image processing system and two video cameras. This method is task requiring measurements of camera lense distortion, calibrations and conversin 2-dimensional images into 3-dimensional images. This system provides 3-dimensional me- asurement error of +5mm for about 2m length objects.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.10
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• pp.1341-1347
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• 2002

In order to improve efficiency of a system with three-dimensional flow characteristics, this paper presents a new method that overcomes three-dimensional effects by using two-dimensional CFD and neural network. The method was applied to shape optimization of cut-off in a multi-blade fan/scroll system. As the entrance conditions of two-dimensional CFD, the experimental values at the positions out of the inactive zone were used. The distributions of velocity and pressure obtained by two-dimensional CFD were compared with those of three-dimensional CFD and experimental results. It was found that the distributions of velocity and pressure have qualitative similarity. The results of two-dimensional CFD were used for teaming as target values of neural network. The optimal angle and radius of cut-off were determined as 71$^{\circ}$and 0.092 times the outer diameter of impeller, respectively. It is quantified in the previous report that the optimal angle and radius of cut-off are approximately 72$^{\circ}$and 0.08 times the outer diameter of impeller, respectively.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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• pp.768-772
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• 2009

This paper proposes a method for measurement three-dimensional trajectories of bubbles generated around a swimmer's arms from stereo high-speed camera videos. This method is based on two techniques: two-dimensional trajectory estimation in single-camera images and trajectory pair matching in stereo-camera images. The two-dimensional trajectory is estimated by block matching using similarity of bubble shape and probability of bubble displacement. The trajectory matching is achieved by a consistensy test using epipolar constraint in multiple frames. The experimental results in two-dimensional trajectory estimation showed the estimation accuracy of 47% solely by the general optical flow estimation, whereas 71% taking the bubble displacement into consideration. This concludes bubble displacement is an efficient aspect in this estimation. In three-dimensional trajectory estimation, bubbles were visually captured moving along the flow generated by an arm; which means an efficient material for swimmers to swim faster.

• Journal of the Korean Geotechnical Society
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• v.36 no.7
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• pp.5-14
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• 2020

Kansai International Airport (KIX) was opened in September 1994. Although 26 years have passed since the completion of the first island, long-term settlement is still in progress. This settlement occurs in the Pleistocene layer. For it is not easy to determine the permeability of the Pleistocene sand layer because the thickness and the degree of fine content in the horizontal direction are constantly changing. In addition, it is also a difficult to predict the interactive behavior of the ground due to the construction of the second phase island adjacent to it. In order to solve this problem, a two-dimensional finite element analysis considering elasto-viscoplastic was performed to evaluate the long-term deformation, including the interactive behavior of the alternating Pleistocene foundation due to the construction of two adjacent reclaimed islands. In general, two-dimensional analysis can be used when a section can represent the entire sections. However, Kansai Airport is an artificial reclaimed island so two-dimensional analysis cannot solve the problem such as the stress deformation in the corners of the island. Additionally, the structure of the actual sub-ground through physical exploration is non-homogeneity and its thickness is also not constant. Therefore, there are limitations for the two-dimensional analysis to explain the phenomena. That is, three-dimensional analysis is strongly required. Due to these demands, the author extended the existing two-dimensional program capable of elasto-viscoplastic analysis to three-dimensional and completed the verification of the three-dimensional program developed through one-dimensional consolidation analysis. In order to demonstrate the validity of the developed 3D program that has been verified, an analysis is performed under the same analysis conditions as the existing research using a two-dimensional program. The effectiveness of the developed 3D numerical analysis program was demonstrated by comparing the analysis results with the 2D results and actual measurement data.