• Biotechnology and Bioprocess Engineering:BBE
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• 제6권6호
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• pp.395-401
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• 2001

Crystallins are a family of water-soluble proteins that constitute up to 90% of the wa-ter-soluble proteins in mammalian eye lenses, We present in this paper an alternative purification method for these proteins using polyethylene glycol/dextran aqueous two-phase extraction. Un-der the appropriate conditions, we were able to recover the γ-crystallin fraction essentially free of the remaining proteins. High concentrations of salt at a neutral pH maximize the recovery of γ-crystallins in the top phase and minimize the contamination by the other proteins present in the lenses. The proposed protocol decreases the separation time by about 50%. The complex partition behavior observed for these proteins reflects a delicate balance between protein/phase-forming species(various polymers and salts) and protein interactions. This is evidenced, in part, by the role played by the largest proteins in this group as a "pseudo"phase-forming species.

• Journal of Information Processing Systems
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• 제16권6호
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• pp.1293-1308
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• 2020

In fine-tuning-based transfer learning, the size of the dataset may affect learning accuracy. When a dataset scale is small, fine-tuning-based transfer-learning methods use high computing costs, similar to a large-scale dataset. We propose a mid-level feature extractor that retrains only the mid-level convolutional layers, resulting in increased efficiency and reduced computing costs. This mid-level feature extractor is likely to provide an effective alternative in training a small-scale medical image dataset. The performance of the mid-level feature extractor is compared with the performance of low- and high-level feature extractors, as well as the fine-tuning method. First, the mid-level feature extractor takes a shorter time to converge than other methods do. Second, it shows good accuracy in validation loss evaluation. Third, it obtains an area under the ROC curve (AUC) of 0.87 in an untrained test dataset that is very different from the training dataset. Fourth, it extracts more clear feature maps about shape and part of the chest in the X-ray than fine-tuning method.

• 대한기계학회논문집A
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• 제26권10호
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• pp.2034-2043
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• 2002

The process design to produce a near net shape home-appliance compressor component using semi-solid die casting process is performed. In order to obtain a good component without defects such as liquid segregation and porosity, the relationship between pressure and time, and plunger tip displacement and injection velocity are proposed with repeated trial and error. The effect of the velocity variation in the process parameters on liquid segregation and extraction is investigated to produce the aluminum frame part(a kind of compressor part) with good mechanical properties. The mechanical characteristic of semi-solid die casting formed parts for AlSi7Mg0.65r(A357) and AlSi17Cu4Mg(A390) are investigated with a view to minimizing the occurrence of defects. To investigate of application possibility at industry field, A380 aluminum alloy with 8∼9% silicon contents used for the squeeze casting process. The obtained mechanical properties is compared with semi-solid die casting.

• 분석과학
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• 제8권4호
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• pp.855-858
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• 1995

Vegetables contain more or less calcium. By the traditional method the total calcium in the vegetable was analyzed. A part or calcium in the vegetable is fixed as calcium oxalate and the calcium does not utilize for nutrition. In this investigation the free calcium was determined by extraction in boiling water, the combined calcium with oxalic acid was determined by extraction in 0.1 M hydrochloric aci and the other calcium combined with protein, amino acid etc. was estimated. The amount of calcium obtained from the difference between the total calcium and calcium exmtaining in calcium oxalate was estimated to be nutritious.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 D
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• pp.2515-2517
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• 2002

The process of character recognition goes through 5 steps; image acquisition, character region extraction, preprocessing, character region segmentation, character recognition. Therefore the final recognition rate of character recognition is directly affected by the performance of each step. This paper is a leading research for object recognition using image processing algorithm which is one of the field of study in computer vision. And this paper will suggest an algorithm to extract the portion of number chain, which is part of the research embodying a system to perceive the data of manufacture and the name of the producer on the wrapping of groceries. In addition, this can extract the number chain comparatively accurate without using many complex algorithm by diving and extracting the moving number region at the same time.

• 전력전자학회논문지
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• 제17권1호
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• pp.8-13
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• 2012

DSTATCOM is active filter that reduces nonlinear and unbalanced currents. Researches about DSTATCOM are mainly divided two parts, one is the reference value calculation of compensation current depending on the calculation of the load-side average active power and dc-link capacitor average voltage, the other part is actual current control depending on the reference value of compensation current. This paper proposes a calculation of dc-link capacitor average voltage ripple voltage extraction instead of conventional method using LPF. The utility of the proposed algorithm is verified through the theoretical analysis and the experiment under unbalance loads and non-linear load.

• East Asian mathematical journal
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• 제38권5호
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• pp.603-610
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• 2022

In [6, 7] they introduced a new finite element method for accurate numerical solutions of Poisson equations with corner singularities. They consider the Poisson equations with homogeneous boundary conditions, compute the finite element solutions using standard FEM and use the extraction formula to compute the stress intensity factor(s), then they posed new PDE with a regular solution by imposing the nonhomogeneous boundary condition using the computed stress intensity factor(s), which converges with optimal speed. From the solution they could get an accurate solution just by adding the singular part. They considered a partial differential equation with the input function f ∈ L²(Ω). In this paper we consider a PDE with the input function f ∈ H¹(Ω) and find the corresponding singular and dual singular functions. We also induce the corresponding extraction formula which are the basic element for the approach.

• 한국철도학회논문집
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• 제2권2호
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• pp.21-30
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• 1999

This study proposes the analysis and evaluation method of time series ultrasonic signal using the phase space-frequency domain. Features extracted from time series signal analyze quantitatively characteristics of weld defects. For this purpose, analysis objectives in this study are features of time domain and frequency domain. Trajectory changes in the attractor indicated a substantial difference in fractal characteristics resulting from distance shifts such as parts of head and flange even though the types of defects are identified. These differences in characteristics of weld defects enables the evaluation of unique characteristics of defects in the weld zone. In quantitative fractal feature extraction, feature values of 3.848 in the case of part of head(crack) and 4.102 in the case of part of web(side hole) and 3.711 in the case of part of flange(crack) were proposed on the basis of fractal dimension. Proposed phase space-frequency domain method in this study can integrity evaluation for defect signals of rail weld zone such as side hole and crack.

• 한국정보과학회논문지:소프트웨어및응용
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• 제37권12호
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• pp.946-950
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• 2010

기계 학습 기반의 많은 감정 분류 시스템들은 문장으로부터 언어적 자질을 추출하기 위하여 형태소 분석기를 사용한다. 그러나 온라인 상품평에는 많은 띄어쓰기 오류 및 철자 오류가 포함되어 있어서 일반적으로 형태소 분석기가 좋은 성능을 내기 어려우며, 기반 시스템의 낮은 성능은 감정 분류 시스템의 성능하락을 초래한다. 이러한 문제를 해결하기 위하여 본 논문에서는 어절 패턴과 음운 패턴의 최장 일치 매칭(matching)에 기반한 자질 추출 방법을 제안한다. 두 종류의 패턴은 대용량의 품사 부착 말뭉치로부터 자동으로 구축된다. 어절 패턴은 영사, 동사와 같은 내용어를 포함하는 어절들로 구성되며, 음운 패턴은 동사나 형용사와 같은 용언의 초성과 중성의 쌍으로 구성된다. 음운 패턴에 초성과 중성만을 사용한 이유는 철자 오류에 영향을 덜 받기 때문이다. 제안 방법을 평가하기 위하여 SVM(Support Vector Machine)을 기계 학습기로 사용하는 감정 분류 시스템을 구현하였다. 한국어 상품평에 대한 실험에서 제안 방법을 자질 추출 모듈로 사용하는 감정 분류 시스템이 형태소 분석기를 사용하는 것보다 우수한 성능을 보였다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권6호
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• pp.3188-3207
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• 2017

In this paper, we propose an image enhancement algorithm to improve license plate extraction rate in various environments (Day Street, Night Street, Underground parking lot, etc.). The proposed algorithm is composed of image enhancement algorithm and license plate extraction algorithm. The image enhancement method can improve an image quality of the degraded image, which utilizes a histogram information and overall gray level distribution of an image. The proposed algorithm employs an interpolated probability distribution value (PDV) in order to control a sudden change in image brightness. Probability distribution value can be calculated using cumulative distribution function (CDF) and probability density function (PDF) of the captured image, whose values are achieved by brightness distribution of the captured image. Also, by adjusting the image enhancement factor of each part region based on image pixel information, it provides a function that can adjust the gradation of the image in more details. This processed gray image is converted into a binary image, which fuses narrow breaks and long thin gulfs, eliminates small holes, and fills gaps in the contour by using morphology operations. Then license plate region is detected based on aspect ratio and license plate size of the bound box drawn on connected license plate areas. The images have been captured by using a video camera or a personal image recorder installed in front of the cars. The captured images have included several license plates on multilane roads. Simulation has been executed using OpenCV and MATLAB. The results show that the extraction success rate is more improved than the conventional algorithms.