• 전자공학회논문지C
• /
• 제34C권4호
• /
• pp.36-44
• /
• 1997

An efficient context-free multiple-object segmentation using attention operator based on modified generalized symmetry transform is proposed and implemented by modifying a radial basis function network. By using the difference of intensity gradient, instead of te intensity gradient itself, in generalized symmetry tranform so as to make the attention operator to preserve the edges of the objects shape, an efficient context-free multiple-object segementation is proposed in which no a priori shape informtion on the objects is requried. The attention operator is implemented by using a modified radial basis function network which can reflect symmetry, and by using te edge pyramid of the input image, both of the local and the global symmetry of the objects are reflected simultaneously to make the multiple-object with different sizes be segmented with a singel fixed-size $n\timesm$ can be done with O(n) complexity. The simulaton results show that the proposed algorithm can efficiently be used in context-free multiple-object segmentation even for the low contrast IR images as well as for the images from the camera.

• Applied Science and Convergence Technology
• /
• 제27권5호
• /
• pp.86-89
• /
• 2018

Observations of neutrino oscillations are very strong evidence for the existence of neutrino masses and mixing. From recent experimental results on neutrino oscillation, we find that neutrino mixing angles are quite consistent with the so-called tri-bi-maximal mixing pattern, but the deviation from observational results is non-negligible. However, the tri-bi-maximal mixing pattern is still useful as a leading order approximation and provides a good guideline to search for the flavor symmetry in the neutrino sector. We introduce the $S_4$ permutation symmetry as a flavor symmetry to the standard model of particle physics with additional particle contents of heavy right-handed neutrinos and scalar fields. Finally, we obtain the tri-bi-maximal mixing pattern as a mixing matrix in the lepton sector within the suggested model. To derive the required unitary mixing matrix for the neutrino sector, the double seesaw mechanism is utilized.

• BMB Reports
• /
• 제29권1호
• /
• pp.92-97
• /
• 1996

The age-46.5 gene of Escherichia coli is induced by nitrate ion and regulated by Fnr, NarL, and NarP during anaerobic growth. aeg-46.5::lacZ fusion gene shows its maximum expression in narL host after two hours of aerobic to anaerobic switch in M9-Glc-nitrate medium. Fnr and NarP act as positive regulators, and NarL acts as a negative regulator. The control region of the aeg-46.5 was identified and the binding sites of regulator proteins have been predicted (Reznikoff and Choe (1993)). It has two symmetry regions. One is located at -52~-37 bp from the anaerobic mRNA 5'-end, which is the binding site of NarL and NarP. The other is located at +37~+56 bp from the 5'-end of mRNA. In this study, the downstream symmetry region from the mRNA 5'-end was investigated by site-directed mutagenesis. The destruction of the symmetry region increases the expression level of aeg-46.5. We propose that the symmetry region interferes with the expression of aeg-46.5 possibly by forming a stem-and-loop structure.

• The Journal of Korean Physical Therapy
• /
• 제25권6호
• /
• pp.399-404
• /
• 2013

Purpose: To investigate the effects of initiation side on gait symmetry in the chronic stroke patients. Methods: Twenty one patients with independent gait after stroke were divided into the paretic-leg gait initiation group (PLI) and the nonparetic-leg gait initiation group (NPLI). The symmetry ratio (SR) was calculated from of the spatiotemoral and kinematic parameter which measured by 3D motion analysis. Results: In the spatiotemporal variables, SR-step length and SR-velocity was significantly different between groups (p<0.05). In the kinematic variables, SR-TOAA and SR-SwPAA of the hip joint was significantly different between groups (p<0.05). Conclusion: We suggest that the initiating leg may influence on the gait symmetry of stroke patient These results will be a helpful reference in hemiplegic gait training or intervention.

• Journal of applied mathematics & informatics
• /
• 제27권3_4호
• /
• pp.915-931
• /
• 2009

The non-rigid molecule group theory in which the dynamical symmetry operations are defined as physical operations is applied to deduce the character table of the full non-rigid molecule group (f-NRG) of 2,3,5,6-Tetramethylpyrazine The f-NRG of this molecule is seen to be isomorphic to the group $\mathbb{Z}_3{\wr}(\mathbb{Z}_2{\times}\mathbb{Z}_2)$, where $\mathbb{Z}_n$ is the cyclic group of order n, of order 324 which has 45 conjugacy classes. We determine the some properties and relations between characters of the group. Also, we examine the symmetry group of this molecule and show that its symmetry group is $\mathbb{Z}_2{\times}\mathbb{Z}_2$.

• 인터넷정보학회논문지
• /
• 제5권1호
• /
• pp.59-66
• /
• 2004

대칭 영역 탐색은 대칭 정보를 이용하여 사전 정보 없이 얼굴영역을 추출 할 수 있다. 그러나 눈, 코, 입 등과 같은 얼굴의 특징 부위보다 탐색할 마스크의 크기가 커져야 함으로 이 방법은 계산 시간이 많이 걸린다. 본 논문에서는 얼굴 영상에 대하여 사전 정보 없이, 적은 계산량으로 얼굴 영역 추출이 가능하도록 대칭 영역 탐색 및 웨이블릿 변환을 이용하여 얼굴 영역의 추출과 그 특징에서의 대칭간에 따른 영상을 이용하여 원영상에서는 영역 분할을 통한 얼굴 영역 추출 방법을 제안하고 실험을 통하여 이를 확인하였다.

• 대한수학회논문집
• /
• 제10권1호
• /
• pp.133-135
• /
• 1995

In this note, we will investigate the radial symmetry of some kind of solutions of nonlinear ellipitic equations $$ \Delta U = f(U) $$ $$ (1.1) U = 0 in B $$ $$ U \in C^2 (\bar{B}) on \partial B$$ Here f is $C^1$ and B denotes a n-dimensional unit ball in $R^n$.

• 한국멀티미디어학회논문지
• /
• 제17권2호
• /
• pp.208-217
• /
• 2014

본 논문은 효과적인 물체 검출이 가능하도록 명도값의 변화방향에 따라 수렴하는 경우와 발산하는 경우의 대칭기여도를 적응적으로 제어할 수 있도록 가우시안 함수형태의 위상가중함수를 이용한 적응적 대칭기여도 제어 기반 일반화 대칭변환을 제안하였다. 제안한 방법에서는 먼저 수렴영역과 발산 영역을 정의한 후 정의된 수렴/발산 영역에서 대칭극점과 거리 함수로 표현된 대칭정도에 따라 대칭기여도의 반영 비율을 달리 할 수 있도록 가우시안함수 형태의 위상가중 함수를 사용하였으며, 가우시안함수 형태의 위상 가중함수에서 차단주파수 조절을 통한 대칭기여도의 적응적인 제어를 통해 효과적인 물체 검출이 가능하도록 하였다. 제안한 방안의 성능을 평가하기 위해 IR영상을 포함한 다양한 영상에서 대해 차단주파수 조절을 통한 대칭기여도의 적응적 제어가 물체검출에 미치는 영향을 기존의 GST와 비교, 분석하여 제안한 방법의 우수한 성능을 증명하였다.

• 대한전자공학회논문지SP
• /
• 제38권4호
• /
• pp.411-421
• /
• 2001

일반화 대칭 변환 (generalized symmetry transform, GST)은 주어진 영상에서 사전 분할이 없이 국부성과 반사 대칭성을 결합하여 대칭을 측정하고 관심 영역을 추출한다. GST의 거리 가중치 함수에서 국부적인 대칭성이 반영되며 이 함수의 표준 편차 u에 의해 GST의 수행 범위가 조절된다. 넓은 관심영역을 추출하기 위해 반지름 r이 큰 검색영역 내에서의 대칭성이 추출될 필요가 있다. 이에 따라서 GST의 수행시간은 r에 따라 2차적으로 증가하게 된 본 논문에서는 이를 개선하기 위해 선택적 방향 주의를 가지는 수정된 스캔라인 GST를 제안한다. 제안된 GST는 기존의 GST와 유사한 대칭 특성을 추출하지만 선택적 방향의 기울기만을 고려한 스캔라인 위의 에지 화소쌍에서 GST를 수행함으로써 r에 따라서 이의 수행시간이 선형적으로 증가된다 특히 r이 큰 경우에 선택적 방향에 대해서만 적용하면 기존의 GST의 계산량이 비대해지는 단점을 보완해 줄 수 있다. 제안된 GST가 기존의 GST보다 시간적으로 효과적이며 유용하다는 것이 여러 종류의 영상에 대한 실험으로 확인되었다.

• 한국컴퓨터정보학회논문지
• /
• 제20권9호
• /
• pp.31-37
• /
• 2015

Symmetry is easily found in animals and plants as well as in artificial structures. It is useful not only for human cognitive process but also for image understanding by computer. Application areas include face detection and recognition, indexing of image database, image segmentation and detection, and analysis of medical images. The method used in this paper extracts edges, and the perpendicular bisector of any pair of selected edge points is considered to be a candidate axis of symmetry. The coefficients of the perpendicular bisectors are accumulated in the coefficient space. Axis of symmetry is determined to be the line for which the histogram has maximum value. This method shows good results, but the usefulness of the method is restricted because the amount of computation increases proportional to the square of the number of edges. In this paper, an acceleration method is proposed which performs $2^{2n}$ times faster than the original one. Experiment on 20 test images shows that the proposed method using level-3 image segmentation performs 63.9 times faster than the original method.