• 한국전자파학회논문지
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• 제15권2호
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• pp.217-222
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• 2004

본 논문에서는 AM 대역 디지틸 라디오 방송의 표준안인 DRM 시스템에 효율적인 채널 추정 방식에 대해 비교, 분석하였다. 채널의 다중경로 페이딩을 보상하기 위해 주파수 영역에서 선형 보간법, 이차 보간법, cubic-spline 보간법, time-domain 보간법을 통하여 채널을 추정하였다. 그리고 잡음에 의한 왜곡을 제거하기 위해 채널의 주파수 응답을 시간축으로 평균을 취하였다. 각 보간 방식의 성능 분석을 위해 시뮬레이션을 수행하여 MSE, BER의 성능과 연산의 복잡도를 비교, 분석하였다.

• IEIE Transactions on Smart Processing and Computing
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• 제3권3호
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• pp.128-134
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• 2014

A real-time, continuous-scale image interpolation method is proposed based on a bilinear interpolation with directionally adaptive low-pass filtering. The proposed algorithm was optimized for hardware implementation. The ordinary bi-linear interpolation method has blocking artifacts. The proposed algorithm solves this problem using directionally adaptive low-pass filtering. The algorithm can also solve the severe blurring problem by selectively choosing low-pass filter coefficients. Therefore, the proposed interpolation algorithm can realize a high-quality image scaler for a range of imaging systems, such as digital cameras, CCTV and digital flat panel displays.

• Structural Engineering and Mechanics
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• 제17권1호
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• pp.87-97
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• 2004

In gradient-dependent plasticity theory, the yield strength depends on the Laplacian of an equivalent plastic strain measure (hardening parameter), and the consistency condition results in a differential equation with respect to the plastic multiplier. The plastic multiplier is then discretized in addition to the usual discretization of the displacements, and the consistency condition is solved simultaneously with the equilibrium equations. The disadvantage is that the plastic multiplier requires a Hermitian interpolation that has four degrees of freedom at each node. Instead of using a Hermitian interpolation, in this article, a 3-node incompatible (trigonometric) interpolation is proposed for the plastic multiplier. This incompatible interpolation uses only the function values of each node, but it is continuous across element boundaries and its second-order derivatives exist within the elements. It greatly reduces the degrees of freedom for a problem, and is shown through a numerical example on localization to yield good results.

• 한국해양공학회지
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• 제8권2호
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• pp.64-79
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• 1994

In this study, terrain classification, which was done by using the quantitative classification parameters and suitable interpolation method was applied to improve the accuracy of digital elevation models, and to increase its practical use of aerial photogrammetry. A terrain area was classified into three groups using the quantitative classification parameters to the ratio of horizontal, inclined area, magnitude of harmonic vectors, deviation of vector, the number of breakline and proposed the suitable interpolation. Also, the accuracy of digital elevation models was improved in case of large grid intervals by applying combined interpolation suitable for each terrain group. As a result of this study, I have an algorithm to perform the classification of the topography in the area of interest objectively and decided optimal data interpolation scheme for given topography.

• 전기학회논문지
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• 제63권5호
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• pp.690-695
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• 2014

This paper presents a modified CCI image interpolation method based on the even-odd decomposition (EOD). The CCI method is a well-known technique to interpolate images. Although the method provides better image quality than the linear interpolation, its complexity still is a problem. To remedy the problem, this paper introduces analysis on the EOD decomposition of CCI and then proposes a reduced CCI interpolation in terms of complexity, providing better image quality in terms of PSNR. To evaluate the proposed method, we conduct experiments and complexity comparison. The results indicate that our method do not only outperforms the existing methods by up to 43% in terms of MSE but also requires low-complexity with 37% less computing time than the CCI method.

• Journal of information and communication convergence engineering
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• 제11권2호
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• pp.118-123
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• 2013

This paper proposes an efficient hardware architecture for high efficiency video coding (HEVC), which is the next generation video compression standard. It adopts several new coding techniques to reduce the bit rate by about 50% compared with the previous one. Unlike the previous H.264/AVC 6-tap interpolation filter, in HEVC, a one-dimensional seven-tap and eight-tap filter is adopted for luma interpolation, but it also increases the complexity and gate area in hardware implementation. In this paper, we propose a parallel architecture to boost the interpolation performance, achieving a luma $4{\times}4$ block interpolation in 2-4 cycles. The proposed architecture contains shared operations reducing the gate count increased due to the parallel architecture. This makes the area efficiency better than the previous design, in the best case, with the performance improved by about 75.15%. It is synthesized with the MagnaChip $0.18{\mu}m$ library and can reach the maximum frequency of 200 MHz.

• 한국정밀공학회지
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• 제17권1호
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• pp.192-197
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• 2000

In CNC machining, a free curve is cut into small linear segments using the linear interpolation(G01) method. Therefore, the interpolation error along the curve is not constant due to the changing curvature. This paper presents a NURBS (Non-Uniform Rational B-Spline) interpolation algorithm for machining free curves with high precision and high speed. The proposed NURBS interpolation defines the tool path with NURBS parameters and limits the interpolation error to any desired level by adjusting the feed rate considering the curvature of the shape and sampling time. Both linear and NURBS interpolations are compared to show the validity of the proposed algorithm.

• Journal of information and communication convergence engineering
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• 제21권1호
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• pp.17-23
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• 2023

Recently, several high-performance instance segmentation models have used the Mask R-CNN model as a baseline, which reached a historical peak in instance segmentation in 2017. There are numerous derived models using the Mask R-CNN model, and if the performance of Mask R-CNN is improved, the performance of the derived models is also anticipated to improve. The Mask R-CNN uses interpolation to adjust the image size, and the input differs depending on the interpolation method. Therefore, in this study, the performance change of Mask R-CNN was compared when various interpolation methods were applied to the transform layer to improve the performance of Mask R-CNN. To train and evaluate the models, this study utilized the PennFudan and Balloon datasets and the AP metric was used to evaluate model performance. As a result of the experiment, the derived Mask R-CNN model showed the best performance when bicubic interpolation was used in the transform layer.

• Journal of applied mathematics & informatics
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• 제7권1호
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• pp.257-267
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• 2000

In this article, we investigate positive interpolation problems in tridiagonal algebra which was introduded by F. Gilfeather and D. Larson.

• 한국멀티미디어학회논문지
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• 제15권2호
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• pp.179-194
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• 2012

디지털 합성 이미지는 이미지가 담고 있는 진정성을 왜곡하기 때문에 사회적인 문제가 되고 있다. 이러한 디지털 합성 이미지들은 인터넷, 잡지 또는 정치적 광고를 위한 이미지들에서 흔히 볼 수 있다. 이러한 왜곡된 매체들은 이미지가 담고 있는 정보에 대한 신뢰도를 떨어트릴 수 있다. 본 논문에서는 이와 같이 대중에게 전달되는 정보의 혼란을 예방하기 위한 연구로써 디지털 합성 이미지를 판독하는데 목적이 있다. 대부분의 합성 이미지들은 이미지 크기 조절 및 회전을 이용하는 방법을 사용하기 때문에 합성 영역에 보간 (Interpolation)이 적용되게 된다. 본 논문은 보간의 흔적을 검출하는 연구로써 이미 보간이 적용된 영역과 그렇지 않은 영역에 재보간을 적용하여 두 영영간의 주파수 패턴을 검출하는 실험을 하였다. 이를 통해 합성에 사용된 보간 흔적을 검출하였으며 이미지 리터칭에 사용된 필터링 영역도 검출할 수 있었다.