• 제목/요약/키워드: snake

검색결과 432건 처리시간 0.03초

변이공간에서 스네이크 알고리즘을 이용한 객체분할에 관한 연구 (A Study on Object Segmentation Using Snake Algorithm in Disparity Space)

  • 유명준;김신형;장종환
    • 정보처리학회논문지B
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    • 제11B권7호
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    • pp.769-778
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    • 2004
  • 본 논문에서는 2차원 영상의 객체분할 방법으로 잘 알려져 있는 Snake 알고리즘을 스테레오 영상(Stereo Image)에 적용할 수 있는 새로운 알고리즘을 제안한다. 기존의 2차원 단일영상에 적용한 Snake 알고리즘은 만족한 결과를 얻기 위해선 분할하려는 객체의 주변 배경이 단순하고, 다른 객체들과 중첩되어 있지 않으며, 초기 Snake 포인트를 객체의 윤곽(Boundary) 가까이에 사용자가 설정해야 하는 문제점이 있다. 본 논문에서는 이러한 문제점을 해결하기 위해 스테레오 영상에서 얻을 수 있는 변이정보(Disparity Iformation)를 이용하여 변이공간(Disparity Space)에서 새로운 Snake 에너지 함수를 정의하였으며, 정의한 에너지 함수를 사용하여 스테레오 영상에 적용할 수 있는 새로운 객체 분할 알고리즘을 제안하였다. 제안한 알고리즘은 복잡도가 다양한 실험영상에 적용하여 성능을 분석하였다.

Adaptive Color Snake Model for Real-Time Object Tracking

  • Seo, Kap-Ho;Jang, Byung-Gi;Lee, Ju-Jang
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2003년도 ICCAS
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    • pp.740-745
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    • 2003
  • Motion tracking and object segmentation are the most fundamental and critical problems in vision tasks suck as motion analysis. An active contour model, snake, was developed as a useful segmenting and tracking tool for rigid or non-rigid objects. Snake is designed no the basis of snake energies. Segmenting and tracking can be executed successfully by energy minimization. In this research, two new paradigms for segmentation and tracking are suggested. First, because the conventional method uses only intensity information, it is difficult to separate an object from its complex background. Therefore, a new energy and design schemes should be proposed for the better segmentation of objects. Second, conventional snake can be applied in situations where the change between images is small. If a fast moving object exists in successive images, conventional snake will not operate well because the moving object may have large differences in its position or shape, between successive images. Snakes's nodes may also fall into the local minima in their motion to the new positions of the target object in the succeeding image. For robust tracking, the condensation algorithm was adopted to control the parameters of the proposed snake model called "adaptive color snake model(SCSM)". The effectiveness of the ACSM is verified by appropriate simulations and experiments.

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개선된 스네이크를 이용한 얼굴 특징요소의 윤곽 추출 (Contour Extraction of Facial Features Based on the Enhanced Snake)

  • 이성수;장종환
    • 정보처리학회논문지:소프트웨어 및 데이터공학
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    • 제4권8호
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    • pp.309-314
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    • 2015
  • 얼굴 요소의 윤곽을 추출하는 대표적인 방법 중의 하나는 스네이크다. 스네이크는 간단하고 빠르지만 초기 윤곽 및 개체 형태에 따라 성능이 결정된다. 본 논문에서는 이러한 문제를 해결하기 위해 스네이크 세그먼트의 중간 위치에 스네이크 포인트를 추가하는 방법으로 윤곽을 더 정확하게 추출할 수 있는 개선된 스네이크를 제안한다. 제안한 방법은 6개의 입과 눈 실험 영상에 적용하여 Greedy 스네이크보다 RSD가 2.8%에서 5.8% 정도 감소하였다. 특히 RSD 감소는 대부분 심한 굴곡이 갖는 윤곽 영역에서 얻음으로써 더 정확한 윤곽 추출을 실험을 통해 확인하였다.

지능형 뱀 로봇에 관한 연구 (Research about Intelligent Snake Robot)

  • 김성주;김종수;전홍태
    • 한국지능시스템학회논문지
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    • 제13권1호
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    • pp.70-75
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    • 2003
  • 기존 이동로봇의 활발한 연구와 더불어 다양한 형태의 이동로봇이 등장하였다. 이에 본 논문에서는 8축으로 구성된, 총 16 Degree Of Freedom을 가지는 다 관절 뱀 로봇을 제작하였다. 뱀 로봇은 지면과의 진행 마찰력을 고려하여 무동력 바퀴를 사용하였다. 또한 PC Cam과 초음파 센서를 사용하여 각 관절이 움직일 수 있는 Joint Angle을 나타내기 위하여 Target의 색상과 거리를 입력으로 하였다. 뱀 로봇은 머리부분, 몸통 그리고 꼬리부분으로 나뉘어 진행하는 방식을 가지며 PC Cam 을 통해 화면에 보여지는 움직이는 특정 목표물에 대하여 진행을 하며, 진행 중 움직이거나 고정되어있는 Obstacle이 포착될 경우 충돌회피를 통하여 Target을 추종하는 방식을 실험적으로 보이고자 한다.

RBF 신경망과 강인 항을 적용한 I-PID 기반 2 자유도 뱀 로봇 머리 제어에 관한 연구 (A Study on I-PID-Based 2-DOF Snake Robot Head Control Scheme Using RBF Neural Network and Robust Term)

  • 김성재;서진호
    • 로봇학회논문지
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    • 제19권2호
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    • pp.139-148
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    • 2024
  • In this paper, we propose a two-degree-of-freedom snake robot head system and an I-PID (Intelligent Proportional-Integral-Derivative)-based controller utilizing RBF (Radial Basis Function) neural network and adaptive robust terms as a control strategy to reduce rotation occurring in the snake robot head. This study proposes a two-degree-of-freedom snake robot head system to avoid complex snake robot dynamics. This system has a control system independent of the snake robot. Subsequently, it utilizes an I-PID controller to implement a control system that can effectively manage rotation at the snake robot head, the robot's nonlinearity, and disturbances. To compensate for the time delay estimation errors occurring in the I-PID control system, an RBF neural network is integrated. Additionally, an adaptive robust term is designed and integrated into the control system to enhance robustness and generate control inputs responsive to signal changes. The proposed controller satisfies stability according to Lyapunov's theory. The proposed control strategy was tested using a 9-degreeof-freedom snake robot. It demonstrates the capability to reduce rotation in Lateral undulation, Rectilinear, and Sidewinding locomotion.

Snake Venom synergized Cytotoxic Effect of Natural Killer Cells on NCI H358 Human Lung Cancer Cell Growth through Induction of Apoptosis

  • Oh, Jae Woo;Song, Ho Sueb
    • Journal of Acupuncture Research
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    • 제33권2호
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    • pp.1-9
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    • 2016
  • Objectives : I investigated whether snake venom can synergistically strengthen the cytotoxic effects of NK-92 cells, and enhance the inhibition of the growth of lung cancer cells including NCI-H358 through the induction of death receptor dependent extrinsic apoptosis. Methods : Snake venom toxin inhibited cell growth of NCI-H358 Cells and exerted non influence on NK-92 cell viability. Moreover, when they were co-cultured with NK cells and concomitantly treated with $4{\mu}g/m{\ell}$ of snake venom toxin, more influence was exerted on the inhibition of growth of NCI-H358 cells than BV or NK cell co-culture alone. Results : The expression of Fas, TNFR2 and DR3 and in NCI-H358 lung cancer cells was significantly increased by co-culture of NK-92 cells and treatment of $4{\mu}g/m{\ell}$ of snake venom toxin, compared to co-culture of NK-92 cells alone. Coincidentally, Bax, caspase-3 and caspase-8 - expressions of pro-apoptotic proteins in the extrinsic apoptosis pathway, demonstrated significant increase. However, in anti-apoptotic NF-${\kappa}B$ activities, activity of the signal molecule was significantly decreased by co-culture of NK-92 cells and treatment of $4{\mu}g/m{\ell}$ of snake venom toxin, compared to co-culture of NK-92 cells or snake venom toxin treated by NCIH358 alone. Meanwhile, in terms of NO generation, there is a significant increase, in co-culture of NK-92 cells with NCI-H358 cells as well as the co-culture of NK-92 cells and concomitant treatment of $4{\mu}g/m{\ell}$ of snake venom toxin. However, no synergistic increase of NO generation was shown in co-culture of NK-92 cells and treatment of $4{\mu}g/m{\ell}$ of snake venom toxin, compared to co-culture of NK-92 cells with NCI-H358 cells. Conclusion : Consequently, this data provides that snake venom toxin could be useful candidate compounds to suppress lung cancer growth along with the cytotoxic effect of NK-92 cells through extrinsic apoptosis.

사독(蛇毒)에 대한 문헌적(文獻的) 고찰(考察) (The Study on The Snake Venom)

  • 이진선;권기록
    • 대한약침학회지
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    • 제2권1호
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    • pp.73-91
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    • 1999
  • This study was carried out to invastigate the researches of Snake Venom and snakes which used in treatment 1. The fist literature that used the snake for treatment is Shin Nong Ben Cao Jing 2. Composition of Snake Venom is consist of Enzymatic proteins ; Phospholipase A(A1-2), Protease, L-amino acid oxidase etc, and Non-enzymatic proteins ; Crotamine(Cytolysin), Proteolytic factor(Hematoxin), Crotoxin(Neurotoxin) etc. 3. Main toxins in Snake Venom are Hematoxin, Cytolysin, Neurotoxin and Cardiotoxin. Lethal dose 50 value of Agkistrodon brevicaudus is $45.87{\mu}g$/18g, Agkistrodon saxatilis is $10.28{\mu}g$/18g, Agkistrodon ussuriensis is $8.68{\mu}g$/18g, therefore Agkistrodon ussuriensis has strongist Snake Venom of all in Korea. 4. Pharmacological actions of Snake Venom are anticoagulation, thrombolytic function, hypotensor etc. 5. Systemic syndromes and signs after snakebite are Dizziness(25.7%), Vomitting(23.1%), Fever(22%), Visual disturbance(18%), Headache(17.7%) and Dyspnea(17.6%), etc. 6. Local syndrome and sign after snakebite is Discoloration(54.2%), Bleeding(20.2%), Bullae(10.7%), Skinulcer(10.8%), etc. 7. Pathological syndromes after snakebite are WBC increase, Urine protein, Urine sugar, Haematuria and elevation of S-GDT, S-GPT etc. These syndromes are leaded by Hematoxin and Cytolysin. 8. Complication signs after snakebite are Cellulitis, Gastritis, Lympoma, Abscess etc. 9. Common function of Viperidae(Agkistrodon acutus or Zaocys dhumnades etc) is expelling the wind(祛風), removing obstruction in the channels(通絡), antipastic function(止痙). And it is used in order to cure hemiparesis, hemiplegia, facial palsy and CVA disease, etc. 10. Using way of snake for medical treatment is various like Herbal alchol therapy, pill, powder and injection etc. The Study on the Snake Venom should be carried out continuously for using of medical treatment.

2 자유도 작동기 모듈로 구성된 뱀 로봇 개발 (Development of a Snake Robot with 2-DOF Actuator Modules)

  • 신호철;정경민;권정주
    • 제어로봇시스템학회논문지
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    • 제17권7호
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    • pp.697-703
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    • 2011
  • This article describes a snake robot with 2-DOF actuator modules. The 2-DOF actuator modules make the snake robot move in the 3D space so that the snake robot can cross obstacles and rough terrain. Each 2-DOF actuator module is designed to have high torque output and an embedded controller. A cross bracket connecting the modules is designed be able to support the weight of two actuator modules. The developed snake robot shows 3-D motions such as side winding, standing/monitoring, and can climb in a narrow pipe with high torque modules. The snake robot moves fast with passive wheels in a plane while crossing obstacles.

Visual Tracking Using Snake Algorithm Based on Optical Flow Information

  • Kim, Won;Lee, Ju-Jang
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1999년도 제14차 학술회의논문집
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    • pp.13-16
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    • 1999
  • An active contour model, Snake, was developed as a useful segmenting and tracking tool lot rigid or non-rigid (i.e. deformable) objects by Kass in 1987 In this research, Snake is newly designed to cover this large moving case. Image flow energy is proposed to give Snake the motion information of the target object. By this image flow energy Snake's nodes can move uniformly along the direction of the target motion in spite of the existences of local minima. Furthermore, when the motion is too large to apply image flow energy to tracking, a jump mode is proposed for solving the problem. The vector used to make Snake's nodes jump to the new location can be obtained by processing the image flow. The effectiveness of the proposed Snake is confirmed by some simulations.

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LM 가이드 상에서 건마찰 접촉을 하면서 운동하는 Cross Head의 사행동에 관한 연구 (A Study on the Snake Motion of a Machine Tool Cross-Head Moving with Dry Friction on LM Guides)

  • 최영휴
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2000년도 춘계학술대회논문집 - 한국공작기계학회
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    • pp.708-713
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    • 2000
  • This paper reviews the concepts of the snake motion which can be often observed on the bodies moving along guide rails. A simple modelling is proposed in order to analyze the snake motion of the cross head assembly and force and moment equilibrium equations are established. It is determined the critical conditions at which snake motion just brings about. Some possible methods to reduce or prevent snake motion are discussed in detail.

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