• 제목/요약/키워드: Visual sequence

검색결과 257건 처리시간 0.025초

Studies of Opsin Genes in a Smelt Fish, Ayu (Plecoglossus altivelis)

  • Minamoto, Toshifumi;Shimizu, Isamu
    • Journal of Photoscience
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    • 제9권2호
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    • pp.269-271
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    • 2002
  • To investigate the visual and extra-ocular photoreception, we cloned the opsin genes in ayu (Plecoglossus allivelis). Amplified fragments encoding exon-4 (-5) of opsin cDNAs were cloned from the retina and brains of ayu, and sequenced. One clone was identified as rod (AYU-Rh), two as green cone (AYU-GI, -G2), one as red cone (A YU-R), two as ultraviolet cone (AYU-UVl, UV2), one as VA (AYU-VA), and one as extra-ocular rod (AYU-ExoRh) opsins. 335 amino acids sequence deduced from the full-length cDNA of AYU-Rh showed high identity with that of other fish. Southern blotting analysis indicated that ayu possess two 'rhodopsin' genes, one is visual rhodopsin and the other is non-visual extra-ocular rhodopsin. In situ hybridization showed that the mRNA of AYU-Rh was localized only in rod cells in the retina. On the other hands, AYU-ExoRh was expressed only in the pineal. We cloned two isoforms (AYU-VAM and -VAL) of VA opsin from ayu. The deduced amino acid sequences of these variants were identical to each other within the first 342 residues, but they showed divergence in the C-terminal sequence. AYU- VAL corresponded to the long isoform found in other fish, and AYU-VAM was identified as a new type of VA opsin variant. Pal-VAM is a new probably functional non-visual photoreceptive molecule in fish.

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복강경 수술용 도구의 실시간 영상 추적 및 복강경 조종기의 지능형 제어 방법 (Real-time Visual Tracking System and Control Method for Laparoscope Manipulator)

  • 김민석;허진석;이정주
    • 한국정밀공학회지
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    • 제21권11호
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    • pp.83-90
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    • 2004
  • In this paper we present a new real-time visual servoing unit for laparoscopic surgery This unit can automatically control laparoscope manipulator through visual tracking of laparoscopic surgical tool. For the tracking, we present two-stage adaptive CONDENSATION(conditional density propagation) algorithm to extract the accurate position of the surgical tool tip from a surgical image sequence in real-time. This algorithm can be adaptable to abrupt change of laparoscope illumination. For the control, we present virtual damper system to control a laparoscope manipulator safely and stably. This system causes the laparoscope to move under constraint of the virtual dampers which are linked to the four sides of image. The visual servoing unit operates the manipulator in real-time with locating the surgical tool in the center of image. The experimental results show that the proposed visual tracking algorithm is highly robust and the controlled manipulator can present stable view with safe.

공간 차원에 관한 시각적 패턴 연구 - 황금비, 피보나치 수열, 프랙털 이론을 중심으로 - (Study on Visual Patterns about Spatial Dimensions - Centered on the Golden Ratio, Fibonacci Sequence, and Fractal Theory -)

  • 김민석;김개천
    • 한국실내디자인학회논문집
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    • 제23권1호
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    • pp.88-95
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    • 2014
  • This study intended arousal of other viewpoints that deal with and understand spaces and shapes, by describing the concept of 'dimensions' into visual patterns. Above all, the core concept of spatial dimensions was defined as 'expandability'. Then, first, the 'golden ratio', 'Fibonacci sequence', and 'fractal theory' were defined as elements of each dimension by stage. Second, a 'unit cell' of one dimension as 'minimum unit particles' was set. Next, Fibonacci sequence was set as an extended concept into two dimensions. Expansion into three dimensions was applied to the concept of 'self-similarity repetition' of 'Fractal'. In 'fractal dimension', the concept of 'regularity of irregularity' was set as a core attribute. Plus, Platonic solids were applied as a background concept of the setting of the 'unit cell' from the viewpoint of 'minimum unit particles'. Third, while 'characteristic patterns' which are shown in the courses of 'expansion' of each dimension were embodied for the visual expression forms of dimensions, expansion forms of dimensions are based on the premise of volume, directional nature, and concept of axes. Expressed shapes of each dimension are shown into visually diverse patterns and unexpected formative aspects, along with the expression of relative blank spaces originated from dualism. On the basis of these results, the 'unit cell' that is set as a concept of theoretical factor can be defined as a minimum factor of a basic algorism caused by other purpose. In here, by applying diverse pattern types, the fact that meaning spaces, shapes, and dimensions can be extracted was suggested.

카오스 시퀀스를 이용한 견고한 디지털 워터마킹 (Robust Digital Watermarking Using Chaotic Sequence)

  • 김현환;정기룡
    • 한국정보통신학회논문지
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    • 제7권4호
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    • pp.630-637
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    • 2003
  • 본 논문에서는 디지털 데이터의 저작권 보호와 무단 복제 방지를 위해 기존의 M-sequence 대신 카오스 시퀀스를 이용한 새로운 워터마킹 방법에 대하여 제안한다. 강인성과 보안성은 워터마킹 처리에 있어 중요한 요소이다. 디지털 영상을 웨이브렛 변환한 후 각 부대역의 계수값들을 인간의 시각 체계를 고려한 다중 임계값으로 분류하고 카오스 시퀀스와 삽입할 워터마크 영상 그리고 랜덤 발생기로 생성된 다중 워터마크 가중치를 이용하여 워터마크 영상을 삽입하였다. 워터마크 검출은 웨이브렛 변환된 각 부대역간의 차신호를 이용하여 검출하였으며 여러가지 가능한 공격에 대해 성능 실험을 하였다. 카오스 시퀀스는 생성하기가 매우 쉬우며, 초기 값에 따라 전혀 다른 시퀀스를 생성하므로 M-sequence에 비해 보안성(security)면에서 더욱 안전하다는 장점을 갖고 있다.

일시적인 시각차단이 만성 뇌졸중 환자의 지면 족저압 분포와 족부면적에 미치는 영향 (The Effects of Temporary Visual Block on the Foot Pressure and Foot Area of Chronic Stroke Patients)

  • 정성화;구현모
    • PNF and Movement
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    • 제17권1호
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    • pp.103-109
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    • 2019
  • Purpose: The purpose of this study was to investigate the effect of temporary visual block existence and nonexistence on the change in foot pressure and foot area in stroke patients. Methods: Sixty-one chronic stroke patients volunteered to participate in the study. Foot pressure and foot area were measured using the Biorescue system. The subject maintain a comfortable standing position on the pressure-measuring plate one meter away from the computer. The sequence of the visual variation data while standing on the measuring plate was collected randomly. The data were collected with three repetitions and used the five-second measuring values except the first second and the last second according to each visual condition. All data were analyzed using SPSS version 21.0. The significance level for the statistical inspection was set as 0.05. Results: The comparison between the visual existence and nonexistence status showed statistically significant effects on foot pressure and foot area. The visual nonexistence status showed more improvement in foot pressure symmetry and area than visual existence status. Conclusion: This study shows that the foot pressure and foot area for the chronic stroke patients changed according to the visual states. It is predicted that these data will be used in rehabilitation training programs and to present temporary changes in visual status for stroke patients.

주의·집중훈련 프로그램의 두 가지 과제수행에 따른 뇌파 변화 (Changes in EEG According to Attention and Concentration Training Programs with Performed Difference Tasks)

  • 채정병
    • PNF and Movement
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    • 제12권2호
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    • pp.97-106
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    • 2014
  • Purpose: The purpose of this study was to investigate changes in EEG through attention. Concentration training and performing tasks are important factors in the improvement of motor learning ability. Methods: In the experiment, 22 healthy people were divided into two groups: the trail making test (TMT) group and the computerized neurocognitive function test (CNT) group. A one-way Neuro Harmony M test to see whether there was a significant difference among the groups. Results: The TMT group showed a significant increase in ${\alpha}$ wave, ${\alpha}$ wave sequence, and ${\beta}$ wave sequence; however, there were no significant differences in SMR wave, SMR wave sequence, and ${\beta}$ wave. The CNT group showed increases in ${\alpha}$ wave, ${\alpha}$ wave sequence, SMR wave, SMR wave sequence, and ${\beta}$ wave sequence; however, there was no significant difference in ${\beta}$ wave. In EEGs before and after two performance tasks were changed, there were significant differences in ${\beta}$ wave, SMR wave, SMR wave sequence; however, there were no significant differences in ${\alpha}$ wave sequence, ${\beta}$ wave, and ${\beta}$ wave sequence. Conclusion: Attention training and concentration training offer feedback and repetition for constant stimulus and response. Moreover, attention training and concentration training can contribute to new studies and motivation by developing fast sensory and motor skills through acceptable visual and auditory stimulation.

절적(截積) 해법의 시각화 (A Visualization of the Solution of Truncated Series)

  • 이경언
    • 한국수학사학회지
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    • 제28권4호
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    • pp.167-179
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    • 2015
  • We study the solution of truncated series of Lee Sang-hyeog with the aspect of visualization. Lee Sang-hyeog solved a problem of truncated series by 4 ways: Shen Kuo' series method, splitting method, difference sequence method, and Ban Chu Cha method. As the structure and solution of truncated series in tertiary number is already clarified with algebraic symbols in some previous research, we express and explain it by visual representation. The explanation and proof of algebraic symbols about truncated series is clear in mathematical aspects; however, it has a lot of difficulties in the aspects of understanding. In other words, it is more effective in the educational situations to provide algebraic symbols after the intuitive understanding of structure and solution of truncated series with visual representation.

시공단계에 따른 철근콘크리트 고층건물의 해석시스템 개발 (Analytical System Development for Reinforced Tall Buildings with Construction Sequence)

  • 이태규
    • 한국콘텐츠학회논문지
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    • 제13권9호
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    • pp.410-417
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    • 2013
  • 시공단계에 따른 철근콘크리트 구조물의 장기변형 해석은 설계 및 시공에 있어서 매우 중요한 요소이다. 하지만 기존의 많은 해석적 연구들은 그 적용기법의 단순화로 인하여 실제 구조설계 및 시공에 대부분 반영되지 못하고 있다. 동바리와 기둥에서는 축력 재분배가 시간에 따라 계속적으로 변화되기 때문에 콘크리트 타설, 거푸집 제거, 동바리 재설치, 동바리 제거 및 이에 따른 추가하중의 작용과 같은 전반적인 시공단계를 그대로 적용하여 해석하는 것은 매우 중요한 요소이다. 따라서 본 논문에서는 이와 같은 시간에 따른 시공단계별 해석을 객체지향 알고리즘으로 개발하였다. 본 시스템에서는 입력모듈, DB 모듈, DB저장 모듈, 해석모듈 및 결과분석모듈로 구분하였으며, 각 모듈간의 연계는 visual c# 루틴으로 처리하였다. 또한 그래픽 인터페이스와 DB 테이블은 사용자 편의성을 고려하여 개발하였다.

b0 Dependent Neuronal Activation in the Diffusion-Based Functional MRI

  • Kim, Hyug-Gi;Jahng, Geon-Ho
    • 한국의학물리학회지:의학물리
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    • 제30권1호
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    • pp.22-31
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    • 2019
  • Purpose: To develop a new diffusion-based functional MRI (fMRI) sequence to generate apparent diffusion coefficient (ADC) maps in single excitation and evaluate the contribution of b0 signal on neuronal changes. Materials and Methods: A diffusion-based fMRI sequence was designed with single measurement that can acquire images of three directions at a time, obtaining $b=0s/mm^2$ during the first baseline condition (b0_b), followed by 107 diffusion-weighted imaging (DWI) with $b=600s/mm^2$ during the baseline and visual stimulation conditions, and another $b=0s/mm^2$ during the last activation condition (b0_a). ADC was mapped in three different ways: 1) using b0_b (ADC_b) for all time points, 2) using b0_a (ADC_a) for all time points, and 3) using b0_b and b0_a (ADC_ba) for baseline and stimulation scans, respectively. The fMRI studies were conducted on the brains of 16 young healthy volunteers using visual stimulations in a 3T MRI system. In addition, the blood oxygen level dependent (BOLD) fMRI was also acquired to compare it with diffusion-based fMRI. A sample t-test was used to investigate the voxel-wise average between the subjects. Results: The BOLD data consisted of only activated voxels. However, ADC_ba data was observed in both deactivated and activated voxels. There were no statistically significant activated or deactivated voxels for DWI, ADC_b, and ADC_a. Conclusions: With the new sequence, neuronal activations can be mapped with visual stimulation as compared to the baseline condition in several areas in the brain. We showed that ADC should be mapped using both DWI and b0 images acquired with the same conditions.

토너 출력문자와 필기구류 기재문자 간 광학적 변화와 선후관계에 관한 연구 (A Study on Optical Changes and Sequence Discrimination of Toner-printed Text and Writing Text)

  • 이가영;윤도영;이중
    • Korean Chemical Engineering Research
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    • 제55권1호
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    • pp.135-140
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    • 2017
  • 본 논문은 법과학 문서분야에서 가장 활발하게 논의되고 있는 주제 중 하나인 상대적 작성시기 판단에 관한 연구이다. 최근 문서 제작에 가장 많이 이용되는 토너 타입의 출력문자와 필기구류 기재문자의 교차 지점을 분광비교분석기 및 무한초점현미경을 이용하여 관찰하였다. 그 결과, 필기구류 종류에 따라 교차지점 형태를 분류할 수 있었고, 문자간 상대적 작성시기 판단에 관한 결과를 도출하였다.