• Title/Summary/Keyword: invariant

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Cathepsin S as a Cancer Therapeutic Target (암 치료 표적으로써 cathepsin S)

  • Woo, Seon Min;Kwon, Taeg Kyu
    • Journal of Life Science
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    • v.28 no.6
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    • pp.753-763
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    • 2018
  • Cysteine cathepsins are lysosomal enzymes that belong to the papain family and can induce the degradation of damaged proteins through the endo-lysosomal pathway. It is highly upregulated in many cancers by regulating gene amplification and transcriptional, translational, and post-transcriptional modifications. Cathepsin S is part of the cysteine cathepsin family. Many studies have demonstrated that cathepsin S not only plays a specific role in MHC class II antigen presentation but also plays a crucial role in cancers. Cathepsin S is more stable at a neutral pH compared to other cysteine cathepsins, which supports the importance of cathepsin S in disease microenvironments. Therefore, the dysregulation of cathepsin S has participated in a variety of pathological processes, including cancer, arthritis, and cardiovascular disease. Furthermore, a decrease or depletion in the expression of cathepsin S has been implicated in the processes of tumor growth, invasion, metastasis, and angiogenesis. Taken together, cathepsin S has been suggested as an attractive therapeutic target for cancer therapy. In this review, the known involvement of cathepsin S in diseases, particularly with respect to recent work indicating its role in cancer therapy, is examined. An overview of current literature on the inhibitors of cathepsin S as a therapeutic target for cancer is also provided.

Integer ambiguity propagation method for a precise positioning using GNSS carrier phase measurements (GNSS 반송파 위상을 이용한 정밀 측위에서 미지정수 전파기법)

  • Han, Deok-Hee;Yun, Hee-Hak;Park, Chan-Sik
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.37 no.7
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    • pp.678-684
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    • 2009
  • Many researches on the GNSS integer ambiguity resolution methods for precise positioning and attitude determination applications have been done. However, by the time invariant property of the integer ambiguity, the reuse of integer ambiguity without performing time consuming integer search procedure is possible. In this paper, a new efficient integer ambiguity propagation method is proposed. The initial integer ambiguity can be determined using the famous LAMBDA method and it is propagated with the propagation method. The proposed method can reconfigure the integer ambiguity using the previous epoch's integer ambiguity and new carrier phase measurements under environmental variations such as geometry changes, signal blockage and reacquisition. Experiments with real measurements show the proposed method can determine an integer ambiguity effectively.

A Comparison of 3D Reconstruction through the Passive and Pseudo-Active Acquisition of Images (수동 및 반자동 영상획득을 통한 3차원 공간복원의 비교)

  • Jeona, MiJeong;Kim, DuBeom;Chai, YoungHo
    • Journal of Broadcast Engineering
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    • v.21 no.1
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    • pp.3-10
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    • 2016
  • In this paper, two reconstructed point cloud sets with the information of 3D features are analyzed. For a certain 3D reconstruction of the interior of a building, the first image set is taken from the sequential passive camera movement along the regular grid path and the second set is from the application of the laser scanning process. Matched key points over all images are obtained by the SIFT(Scale Invariant Feature Transformation) algorithm and are used for the registration of the point cloud data. The obtained results are point cloud number, average density of point cloud and the generating time for point cloud. Experimental results show the necessity of images from the additional sensors as well as the images from the camera for the more accurate 3D reconstruction of the interior of a building.

Mosaic image generation of AISA Eagle hyperspectral sensor using SIFT method (SIFT 기법을 이용한 AISA Eagle 초분광센서의 모자이크영상 생성)

  • Han, You Kyung;Kim, Yong Il;Han, Dong Yeob;Choi, Jae Wan
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.31 no.2
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    • pp.165-172
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    • 2013
  • In this paper, high-quality mosaic image is generated by high-resolution hyperspectral strip images using scale-invariant feature transform (SIFT) algorithm, which is one of the representative image matching methods. The experiments are applied to AISA Eagle images geo-referenced by using GPS/INS information acquired when it was taken on flight. The matching points between three strips of hyperspectral images are extracted using SIFT method, and the transformation models between images are constructed from the points. Mosaic image is, then, generated using the transformation models constructed from corresponding images. Optimal band appropriate for the matching point extraction is determined by selecting representative bands of hyperspectral data and analyzing the matched results based on each band. Mosaic image generated by proposed method is visually compared with the mosaic image generated from initial geo-referenced AISA hyperspectral images. From the comparison, we could estimate geometrical accuracy of generated mosaic image and analyze the efficiency of our methodology.

A Study on Feature Information Parsing of Video Image Using Improved Moment Invariant (향상된 불변모멘트를 이용한 동영상 이미지의 특징정보 분석에 관한 연구)

  • Lee, Chang-Soo;Jun, Moon-Seog
    • Journal of Korea Multimedia Society
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    • v.8 no.4
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    • pp.450-460
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    • 2005
  • Today, multimedia information is used on the internet and various social areas by rapid development of computer and communication technology. Therefor, the usage is growing dramatically. Multimedia information analysis system is basically based on text. So, there are many difficult problems like expressing ambiguity of multimedia information, excessive burden of works in appending notes and a lack of objectivity. In this study, we suggest a method which uses color and shape information of multimedia image partitions efficiently analyze a large amount of multimedia information. Partitions use field growth and union method. To extract color information, we use distinctive information which matches with a representative color from converting process from RGB(Red Green Blue) to HSI(Hue Saturation Intensity). Also, we use IMI(Improved Moment Invariants) which target to only outline pixels of an object and execute computing as shape information.

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Detection of Void Defects in Ball Grid Array X-ray Image Using a New Blob Filter (볼 그리드 배열 기판의 X-ray 영상에서의 새로운 덩어리 검출 필터를 이용한 기포 형태 결함 검출 방법)

  • Peng, Shao-Hu;Lee, Hye-Jung;Nam, Hyun-Do
    • Proceedings of the KIEE Conference
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    • 2011.07a
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    • pp.2005-2006
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    • 2011
  • Due to the advantages of small sizes, more I/O ports, etc., Ball Grid Array (BGA) has been used in the production of printed circuit board (PCB). However, BGA voids can degrade the performance of the board and cause failure. To automatically detect the voids in X-ray image, a novel blob filter that makes use of the local image gradient magnitude is proposed in this paper. The utilization of the local image gradient magnitude makes the proposed filter invariant to the image brightness, void shape, void position, and component interference. Furthermore, different sizes of box filters are employed to analyze the image in multi-scale, and as a result, the proposed blob filter is robust to void size. Experimental results show that the proposed method can obtain void detection accuracy up to 96.104% while keep low false ratio.

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Color Landmark Based Self-Localization for Indoor Mobile Robots (이동 로봇을 위한 컬러 표식 기반 자기 위치 추정 기법)

  • Yoon, Kuk-Jin;Jang, Gi-Jeong;Kim, Sung-Ho;Kweon, In-So
    • Journal of Institute of Control, Robotics and Systems
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    • v.7 no.9
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    • pp.749-757
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    • 2001
  • We present a simple artificial landmark model and robust landmark tracking algorithm for mobile robot localization. The landmark model, consisting of symmetric and repetitive color patches, produces color histograms that are invariant under the geometric and photometric distortions. A stochastic approach based on the CONDENSATION tracks the landmark model robustly even under the varying illumination conditions. After the landmark detection, relative position of the mobile robot to the landmark is calculated. Experimental results show that the proposed landmark model is effective and can be detected and tracked in a clustered scene robustly. With the tracked single landmark, we extract geometrical information than achieve accurate localization.

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Stability Condition for Discrete Interval System with Time-Varying Delay Time (시변 지연시간을 갖는 이산 구간 시스템의 안정조건)

  • Han, Hyung-seok
    • Journal of Advanced Navigation Technology
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    • v.19 no.6
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    • pp.574-580
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    • 2015
  • The stability condition of linear discrete interval systems with a time-varying delay time is considered. The considered system has interval system matrices for both non-delayed and delayed states with time-varying delay time within given interval values. The proposed condition is derived by using Lyapunov stability theory and expressed by very simple inequality. Compared to previous results, the stability issue on the interval systems is expanded to time-varying delay. Furthermore, the new condition can imply the existing results on the time-invariant case and show the relation between interval time-varying delay time and stability of the system. The proposed condition can be applied to find the stability bound of the discrete interval system. Some numerical examples are given to show the effectiveness of the new condition and comparisons with the previously reported results are also presented.

Region-based Shape Descriptor with Moving a Vision Center for Image Representation (영상표현을 위한 비전 중심점 이동에 따른 영역기반 형태 기술자)

  • Kim Seon-Jong;Kim Young-In
    • Journal of Intelligence and Information Systems
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    • v.12 no.1
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    • pp.95-105
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    • 2006
  • This paper proposes a novel approach to represent the image by using shape descriptor having an information of area. The proposed descriptor is a set of vectors, consists of radius, area and direction parameters in the concentrated center point. Due to the area parameter, we know our descriptor can obtain the information of area. Also, we give an extended shape descriptor to get more detailed representation. To do this, we move the center point of our vision to that point for region of interest. By doing so about all of region of interest, we can get our descriptor for detailed information of the image. From more detailed descriptor, it's natural that it's more efficient fur representation, retrievals and so on. We make it the normalized pattern and expand to improve its quality. The proposed method is invariant to scale, position and rotation. The results show that it can be used efficiently for image representation as we can see in retrievals of silhouette images.

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A UCP-based Model to Estimate the Software Development Cost (소프트웨어 개발 비용을 추정하기 위한 사용사례 점수 기반 모델)

  • Park, Ju-Seok;Chong, Ki-Won
    • The KIPS Transactions:PartD
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    • v.11D no.1
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    • pp.163-172
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    • 2004
  • In the software development project applying object-oriented development methodology, the research on the UCP(Use Case Point) as a method to estimate development effort is being carried on. The existing research proposes the linear model calculating the development effort that multiplies an invariant on AUCP(Adjusted Use Case Point) which applied technical and environmental factors. However, the statistical model that estimates the development effort using AUCP and UUCP(Unadjusted Use Case Point) is not being studied. The irrelevant relationship of the linear regression model, whose development period is increasing tremendously as the software size increases, is confirmed. Moreover, during the UCP calculating process, there can be errors in FP by applying the TCF(Technical Complexity Factor) and EF(Environmental Factor). This paper presents a non-linear regression model, that does not consider the TCF and EF, and that estimate the development effort from UUCP directly by utilizing the exponential function. An exponential function is selected among the linear, logarithm, polynomial, power, and exponential model via statistical evaluations of the models mentioned above.