• Title, Summary, Keyword: 대칭성

Search Result 1,145, Processing Time 0.054 seconds

A Modified Bresenham's Line Drawing Algorithm Using Symmetrical Property of Line Segment (직선 선분의 대칭성을 이용한 수정 브레제남 직선 그리기 알고리즘)

  • Lee, Sang-Rak;Hong, Yun-Sik
    • The Transactions of the Korea Information Processing Society
    • /
    • v.6 no.8
    • /
    • pp.2213-2221
    • /
    • 1999
  • A line segment has a symmetrical property about its midpoint. With this symmetrical property for a line segment we have proposed a variant of Bresenham's line drawing algorithm that selects two pixels at the same time. It implies that bi-directional line drawing toward the midpoint of line segment from each-end be possible. Besiders, it can select two pixels using only one decision parameter, instead of two different parameters for each pixel. We also present a theoretical proof for the correctness of such a selection. Thus, we can reduce the time of generating line segment by approximately less than 5% compared to the Bresenham's method. Also, our experimental results show that the shape of line segment generated by the proposed approach is the exactly same as that of Bresenham's method.

  • PDF

On the Weight and Nonlinearity of Quadratic Rotation Symmetric Boolean Functions (회전대칭 이차 불함수의 해밍무게 및 비선형성)

  • Kim, Hyeon-Jin;Jung, Chang-Ho;Park, Il-Hwan
    • Journal of the Korea Institute of Information Security & Cryptology
    • /
    • v.19 no.2
    • /
    • pp.23-30
    • /
    • 2009
  • Recently, rotation symmetric Boolean functions have attracted attention since they are suitable for fast evaluation and show good cryptographic properties. For example, important problems in coding theory were settled by searching the desired functions in the rotation symmetric function space. Moreover, they are applied to designing fast hashing algorithms. On the other hand, for some homogeneous rotation symmetric quadratic functions of simple structure, the exact formulas for their Hamming weights and nonlinearity were found[2,8]. Very recently, more formulations were carried out for much broader class of the functions[6]. In this paper, we make a further improvement by deriving the formula for the Hamming weight of quadratic rotation symmetric functions containing linear terms.

Benign Symmetrical Lipomatosis (Madelung's Disease) -A case report- (양성 대칭성 지방종증 -1예 보고-)

  • Han Jong-Hee;Kang Min-Woong;Yu Jae-Hyeon;Lim Seung-Pyung;Lee Young;Na Myung-Hoon
    • Journal of Chest Surgery
    • /
    • v.39 no.5
    • /
    • pp.419-422
    • /
    • 2006
  • Benign symmetric lipomatosis (BSL), also called Madelung's disease, is a rare disease in middle-aged chronic alcohol user. The cause of BSL is unknown. A 63 year-old man with rapid growing lesions in both shoulders for 2 months visited our hospital. Except for cosmetic problem, no abnormal finding was found in blood cell analysis and chemistry; however, excessive fat deposition was found on radiographic findings. Lipoma was revealed in pathologic examination and BSL was diagnosed clinically. Patient is being followed up without any specific problem.

An Efficient Computation Method of Zernike Moments Using Symmetric Properties of the Basis Function (기저 함수의 대칭성을 이용한 저니키 모멘트의 효율적인 계산 방법)

  • 황선규;김회율
    • Journal of KIISE:Software and Applications
    • /
    • v.31 no.5
    • /
    • pp.563-569
    • /
    • 2004
  • A set of Zernike moments has been successfully used for object recognition or content-based image retrieval systems. Real time applications using Zernike moments, however, have been limited due to its complicated definition. Conventional methods to compute Zernike moments fast have focused mainly on the radial components of the moments. In this paper, utilizing symmetric/anti-symmetric properties of Zernike basis functions, we propose a fast and efficient method for Zernike moments. By reducing the number of operations to one quarter of the conventional methods in the proposed method, the computation time to generate Zernike basis functions was reduced to about 20% compared with conventional methods. In addition, the amount of memory required for efficient computation of the moments is also reduced to a quarter. We also showed that the algorithm can be extended to compute the similar classes of rotational moments, such as pseudo-Zernike moments, and ART descriptors in same manner.

An Efficient Medical Image Compression Considering Brain CT Images with Bilateral Symmetry (뇌 CT 영상의 대칭성을 고려한 관심영역 중심의 효율적인 의료영상 압축)

  • Jung, Jae-Sung;Lee, Chang-Hun
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.12 no.5
    • /
    • pp.39-54
    • /
    • 2012
  • Picture Archiving and Communication System (PACS) has been planted as one of the key infrastructures with an overall improvement in standards of medical informationization and the stream of digital hospitalization in recent days. The kind and data of digital medical imagery are also increasing rapidly in volume. This trend emphasizes the medical image compression for storing large-scale medical image data. Digital Imaging and Communications in Medicine (DICOM), de facto standard in digital medical imagery, specifies Run Length Encode (RLE), which is the typical lossless data compressing technique, for the medical image compression. However, the RLE is not appropriate approach for medical image data with bilateral symmetry of the human organism. we suggest two preprocessing algorithms that detect interested area, the minimum bounding rectangle, in a medical image to enhance data compression efficiency and that re-code image pixel values to reduce data size according to the symmetry characteristics in the interested area, and also presents an improved image compression technique for brain CT imagery with high bilateral symmetry. As the result of experiment, the suggested approach shows higher data compression ratio than the RLE compression in the DICOM standard without detecting interested area in images.

The Strategy and Techniques of Welfare Discourse of the Conservative Newspapers (한국 보수언론의 복지담론 전략과 기술 -대칭, 재맥락화, 주체 형성의 담론 기술(technique)-)

  • Joo, Eunsun
    • Korean Journal of Social Welfare
    • /
    • v.65 no.2
    • /
    • pp.357-384
    • /
    • 2013
  • In this study I've analyzed the strategy and techniques of the welfare discourses of korean conservative newspapers based on the discourse theory. Emphasizing the political and social characteristics of the discourse, It is investigated the way that the conservative newspapers criticize against assertions for welfare increase and universal welfare and the way that produce social meaning on welfare. The study is focused on the discourse techniques like symmetrical contrasts, making new contexts, and formation of identity. The critical welfare discourses are structured according to symmetrical contrasts of welfare to the rationality, the morality, and the prospects for future. The elements of the discourses are reinforced by one another and were recontextualized to the new stories on welfare. The conservative newspapers had emphasized secession welfare from the politics, solving the problem of inefficiency of welfare administration. Regarding the technique of identification, the newspapers had treated people as owners and victims of welfare on the role of financing welfare expenditure. It is noteworthy the newspapers have began to call people separately according to generations and income class using finance.

  • PDF

The Effect of Symmetrical and Asymmetric Bilateral Training for Chronic Stroke Patients in Upper Extremity Recovery (만성 뇌졸중 환자의 대칭적, 비대칭적 양측성 상지훈련의 상지기능회복 효과)

  • Kim, Sun Ho;Han, Dae Sung
    • Therapeutic Science for Rehabilitation
    • /
    • v.6 no.1
    • /
    • pp.35-43
    • /
    • 2017
  • Objective : To identify the effect of symmetrical and asymmetric bilateral training For stroke patients in upper extremity recovery. Methods : 15 patients with stroke, randomized to an in- phase group(n =7) and anti-phase group(n =8). Each groups received symmetrical and asymmetric bilateral training, 30-min sessions per a day for 5 weeks, total 20 session.Accelerometer was used to evaluate the amount used for both groups. Y-BAT was used to evaluate performance status and satisfaction, ARAT was used to evaluate hand function. Results : the amount used of symmetrical movement training showed significant changes in affected and unaffected side. asymmetric bilateral training. there is a significant difference in affected side before and after receiving asymmetric bilateral training. Also, There was a significant difference between the groups on the affected side. Both training, there was no significant difference in performance, satisfaction, and upper limb function between group but, there was significant differences within-groups, Conclusions : Symmetric training showed higher motor performance than asymmetric training, but, To obtain a clearer difference, it would be necessary to use a neuromuscular assessment tool such as fMRI. Also, need a clearer training protocol and the need for follow-up studies on more stroke patients is suggested.