• Proceedings of the KIEE Conference
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• 2008.10b
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• pp.262-263
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• 2008

LCD 디바이스는 그 동작원리와 전기-광학적 특성에 의해 CRT와는 다른 감마곡선 특성을 갖고 있다. 대부분의 LCD디스플레이 디바이스들의 감마곡선은 CRT와는 달리 일관성을 갖지 않을 뿐 더러 흑백계조입력을 기준으로 하는 감마보정을 위해 RED, GREEN, BLUE 입력값을 세부적으로 조정할 때 각 계조입력에 대한 상관색온도가 일정한 값을 갖지 않아 LCD의 특성에 대한 모델링과 보정에 어려움이 있다. 또한, 애플사의 맥머신 그리고 실리콘 그래픽스사의 시스템과 같이 소정의 감마값을 전제로 해당 시스템의 내부참조테이블(internal look-up table)이 설계되어 각기 다른 시스템감마를 가지는 장치들에 의해 인코딩되어진 영상출력신호의 경우, 동일한 시스템을 갖추거나 시스템감마에 대한 역감마특성을 가진 디스플레이장치가 아닌 환경에서는 원본영상에 대한 왜곡은 더욱 커질 수 있다. 특히, 낮은 흑백계조입력에서의 색온도의 경우, 파장에 따라 서로 다른 감쇄성능을 가진 일반적인 컬러필터의 특성에 의한 누설광(light leakage)에 의해 결정되며, 이로 인해 색온도가 특정한 객을 띄는 현상이 발생한다. 본 논문에서는 LCD디스플레이의 감마곡선을 여러 가지 시스템감마에 대응할 수 있는 감마곡선예 일치시키고, 계조선형성을 동시에 개선하기 위하여 입력 디지털값과 삼자극치간 관계를 나타내는 여러 가지 컬러모델링 방법 중에서 PLCC(Piecewise Linear Interpolation assuming Constant Chromaticity coordinates)모델을 적용하고, 목표로 하는 감마곡선과 색온도를 만족하기 위한 새로운 입력값을 구한 후 이를 컬러참조테이블(color look-up table)예 적용하는 방법과 저계조에서의 색온도를 목표색온도에 근접시키는 방법을 제안한다.

• Journal of Digital Contents Society
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• v.18 no.7
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• pp.1419-1425
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• 2017

The ultimate goal of legal knowledge search is to obtain optimal legal information based on laws and precedent. Text mining research is actively being undertaken to meet the needs of efficient retrieval from large scale data. A typical method is to use a word embedding algorithm based on Neural Net. This paper demonstrates how to search relevant information, applying Korean law information to word embedding. First, we extracts reference laws from precedents in order and takes reference laws as input of Law2Vec. The model learns a law by predicting its surrounding context law. The algorithm then moves over each law in the corpus and repeats the training step. After the training finished, we could infer the relationship between the laws via the embedding method. The search performance was evaluated based on precision and the recall rate which are computed from how closely the results are associated to the search terms. The test result proved that what this paper proposes is much more useful compared to existing systems utilizing only keyword search when it comes to extracting related laws.

• Korean Journal of Construction Engineering and Management
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• v.7 no.2 s.30
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• pp.138-147
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• 2006

The objective of this research is to explore a more precise forecasting method by applying Case-based Reasoning (CBR). The newly suggested method in this study enables project managers to forecast monthly expenditures with less time and effort by retrieving and referring only projects of a similar nature, while filtering out irrelevant cases included in database. For the purpose of accurate forecasting, 1) the choice of the numbers of referring projects and 2) the better selection among three levels ? which include a 20-work package level, a 7-major work package level, and a total sum level analysis, were investigated in detail. It is concluded that selecting similar projects at $12{\sim}19%$ out of the whole database will produce a more precise forecasting. The new forecasting model, which suggests the predicted values based on previous projects, is more than just a forecasting methodology; it provides a bridge that enables current data collection techniques to be used within the context of the accumulated information. This will eventually help all the participants in the construction industry to build up the knowledge derived from invaluable experience.

• The Journal of Korean Association of Computer Education
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• v.18 no.4
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• pp.55-62
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• 2015

Recommender systems through collaborative filtering has been utilized successfully in various areas by providing with convenience in searching information. Measuring similarity is critical in determining performance of these systems, because it is the criteria for the range of recommenders. This study analyzes distributions of similarity from traditional measures and investigates relations between similarities and the number of co-rated items. With this, this study suggests a method for selecting reliable recommenders by restricting similarities, which compensates for the drawbacks of previous measures. Experimental results showed that restricting similarities of neighbors by upper and lower thresholds yield superior performance than previous methods, especially when consulting fewer nearest neighbors. Maximum improvement of 0.047 for cosine similarity and that of 0.03 for Pearson was achieved. This result tells that a collaborative filtering system using Pearson or cosine similarities should not consult neighbors with very high or low similarities.

• The KIPS Transactions:PartB
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• v.13B no.5 s.108
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• pp.499-506
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• 2006

This Paper describes a fast and stable camera pose estimation method for real-time augmented reality systems. From the feature tracking results of a marker on a single frame, we estimate the camera rotation matrix and the translation vector. For the camera pose estimation, we use the shape factorization method based on the scaled orthographic Projection model. In the scaled orthographic factorization method, all feature points of an object are assumed roughly at the same distance from the camera, which means the selected reference point and the object shape affect the accuracy of the estimation. This paper proposes a flexible and stable selection method for the reference point. Based on the proposed method, we implemented a video augmentation system that inserts virtual 3D objects into the input video frames. Experimental results showed that the proposed camera pose estimation method is fast and robust relative to the previous methods and it is applicable to various augmented reality applications.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.49 no.4
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• pp.23-31
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• 2012

This paper proposes a motion estimation-based super resolution algorithm to restore input low-resolution images of large movement into a super-resolution image. It is difficult to find the sub-pixel motion estimation in images of large movement compared to typical experimental images. Also, it has disadvantage which have high computational complexity to find reference images and candidate images using general motion estimation method. In order to solve these problems for the traditional two-dimensional motion estimation using the proposed registration threshold that satisfy the conditions based on the reference image is determined. Candidate image with minimum weight among the best candidates for super resolution images, the restoration process to proceed with to find a new image registration algorithm is proposed. According to experimental results, the average PSNR of the proposed algorithm is 31.89dB and this is better than PSNR of traditional super-resolution algorithm and it also shows improvement of computational complexity.

• Spatial Information Research
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• v.14 no.3 s.38
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• pp.271-284
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• 2006

This study suggests the adjustment method of cadastral non-coincidence using spatial data referenced digital cadastral map and a present state. In designing the methodology, we should introduce the semi-automatic method for guaranteeing the stability and the accuracy at the arrangement of cadastral non-coincidence based on some cadastral specialist. This study could mainly show you rotation type, bias type, and rotation/bias type among cadastral non-coincidence types. We selected the matching reference point through the prototype system which automatically arranges in the study area. And then, we analysis the optimum rotation ratio(-0.4%). Finally, this paper show you calibrating cadastral non-coincidence using the rotation ratio. The methodology of this study has a limitation for arranging in case of cadastral non-coincidence by the area variation and some irregular types with unknown reason. Therefore, this case should be surveyed in direct method.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.4
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• pp.634-640
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• 2018

In this paper, we propose an automatic extraction algorithm of region of interest(ROI) based on medical x-ray images. The proposed algorithm uses segmentation, feature extraction, and reference image matching to detect lesion sites in the input image. The extracted region is searched for matching lesion images in the reference DB, and the matched results are automatically extracted using the Kalman filter based fitness feedback. The proposed algorithm is extracts the contour of the left hand image for extract growth plate based on the left x-ray input image. It creates a candidate region using multi scale Hessian-matrix based sessionization. As a result, the proposed algorithm was able to split rapidly in 0.02 seconds during the ROI segmentation phase, also when extracting ROI based on segmented image 0.53, the reinforcement phase was able to perform very accurate image segmentation in 0.49 seconds.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.113-116
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• 2008

According to a domestic provision, test levels of the barrier are divided into seven categories(SB1 to SB7) and the corresponding crash conditions are specified. Meanwhile, standard types of concrete barriers with different dimensions have been constructed nation wide. Some studies aimed at finding a proper test level of each type of the concrete barrier have been carried out, but the reliable and consistent results have not been fully established yet. The purpose of this study is to find out the test level corresponding to the concrete barrier of type-2 through static test. AASHTO LRFD was referred to for the loading pattern and a magnitude of the load that simulate a vehicle crash assumed. The test results show that the ultimate strength of the type-2 satisfies the load level required for SB5. However, it seems that the type-2 does not comply with SB6, showing some differences in results from previous analytical studies. In order to take advantage of the static test in establishing the test level of the domestic barrier, more detailed provisions should be specified.

• Journal of Digital Convergence
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• v.15 no.2
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• pp.199-206
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• 2017

Embedded control system is widely spreaded and used in various fields including military defence, aviation, medical, etc. due to extended use of smart phones, connected car, IoT. Increasing examples are introduced where embedded control system that perform their unique role such as smart phone and network system organically configure to create new system. According to this trend, organic interface and reliability of each embedded control system are becoming important evaluation factors. The purpose of this paper is to develop quality evaluation criteria method for automobile embedded system, among the fields that use embedded control systems. In order to satisfy high quality level requirements of automobile embedded control system, we surveyed latest trend of automobile embedded control system, analyzed structure and application technology of embedded control system, to establish quality evaluation criteria and method for automobile embedded control system by referring international standard for software (ISO/IEC 9126), and international standard for electric & electronic products (ISO 26262).