• Journal of Institute of Control, Robotics and Systems
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• v.15 no.6
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• pp.604-611
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• 2009

Modular snake-like robots are robust for failure and have flexible locomotion for environments, but are difficult to control. Various phase and evolutionary approaches for modular robots have been studied for many years, but there are few comparisons among these methods. In this paper, Phase, GAps, GA and GP approaches are implemented and compared for flat, stairs, and slope environments. In addition, simulations of the locomotion evolution for modular snake-like robot are executed in Webots environments.

• Proceedings of the IEEK Conference
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• 2001.09a
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• pp.891-894
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• 2001

본 논문에서는 NTGST (noise·tolerant generalized symmetry transform)와 snake를 이용하여 복잡배경으로부터 여러 물체의 윤곽선을 동시에 검출하는 방법을 제안하였다. 먼저 NTCST의 대칭도 맵(symmetry map)을 이용하여 복잡한 배경에 혼재하는 여러 물체들의 위치를 찾은 다음, 이들 각 물체에 snake의 초기 윤곽들을 자동 설정해 줌으로써 기존 snake 알고리즘의 초기 윤곽 설정의 어려움과 다중 물체 윤곽선 검출의 어려움을 동시에 해결하였다. 이때 NTGST의 대칭도 맵으로부터 설정된 snake의 초기 윤곽은 실제 물체의 윤곽선 가까이에 위치할 뿐만 아니라 물체의 형태를 잘 반영하므로 요철이 있는 물체의 윤곽선도 기존의 방법보다 적은 반복횟수로 정확하게 검출 할 수 있다. 다양한 합성 영상과 실영상에 적용한 결과 복잡배경으로부터도 다중 물체의 윤곽선을 효과적으로 추출함을 확인하였다.

• Journal of Korea Multimedia Society
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• v.3 no.5
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• pp.445-453
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• 2000

In this paper we propose the method which extracts lane using the grouped block snake algorithm. In the proposed algorithm, input image is divided into $8\times{8}$ blocks and then noise-included blocks are removed by a probability-based method. And also, we use hough transform to separate lane from the background image and suggest a grouped block snake method to detect road lane blocks. The proposed method reduces computational complexity and removes the noise in a more effective way compared to the pixel-based snake method.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.57.4-57
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• 2002

$\textbullet$ Image segmentation is an essential technique of image analysis. In spite of the traditional issues in contour initialization and boundary concavities, active contour models(snakes) are popular and known as successful methods for segmentation. $\textbullet$ We could find in experiment that snake using Gaussian External Force is fast in time but low in accuracy and snake using Gradient Vector Flow by Chenyang Xu and Jerry L. Prince is high in accuracy but slow in time. $\textbullet$ In this paper, we presented a new active contour model, GGF snake, for segmentation of endoscopic image. Proposed GGF snake made up for the defects of the traditional snakes in contour initialization and boundary...

• Proceedings of the KSR Conference
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• 2002.10a
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• pp.193-201
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• 2002

The development of railway vehicle and bogie involves the proper selection of design parameters not only to achieve high speed but also to reduce the vibration of the train. In this study an analytical model of a high speed freight car is developed to find the critical speed. The high speed freight car can generate the snake motion of the lateral and yawing motion of the car body, the bogie, and the wheelset. Numerical analysis for the nonlinear equation motions with 17 degrees of freedom showed the running stability and critical speed due to the snake motion. Also, the vibration modes of tile high speed freight car was calculated using ADAMS RAIL, which showed that the critical speed have the yawing modes of the car body and the bogie. Finally, this paper shows that the snake motion of the vehicle can be controlled with the modifications of the design parameters.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.12
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• pp.1678-1684
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• 2018

Dental caries is one of the most popular oral disease. The aim of automatic dental cavity detection system is helping dentist to make accurate diagnosis. It is very important to separate cavity from the teeth in the detection system. In this paper, We compared two active contour algorithms, Snake and DRLSE(Distance Regularized Level Set Evolution). To improve performance, image is selected ROI(region of interest), then applied bilateral filter, Canny edge. In order to evaluate the algorithms, we applied to 7 tooth phantoms from incisor to molar. Each teeth contains two cavities of different shape. As a result, Snake is faster than DRLSE, but Snake has limitation to compute topology of objects. DRLSE is slower but those of performance is better.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.307-308
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• 2012

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.10a
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• pp.917-918
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• 2012

• The KIPS Transactions:PartB
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• v.15B no.4
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• pp.269-274
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• 2008

In this paper, we propose a new stereo correspondence method for generating excellent external energy for snake-based object segmentation methods in stereo images. Our method first generates an edge-based disparity map by performing stereo correspondence between multi-level edge maps of the stereo image pair. Only edges of similar strength are considered for matching. To filter the disparity map for edges of the object of interest, the method estimates the object's disparity value by matching the pattern of edges of the region of interest in the left image against candidate patterns in the right image. The filtered edge map is then used to generate external energy for the snake. The proposed method has been tested on two snake models and results show a noticeable enhancement on performance of the snake when compared with other methods.

• Journal of The Korean Society of Clinical Toxicology
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• v.15 no.1
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• pp.1-10
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• 2017

Purpose: This study was conducted to identify predictors of serious poisoning in patients with snake bite based on initial findings. Methods: We conducted a retrospective study of patients with snake bite who were treated at the emergency department between January 2010 and December 2016. The patients were divided into two groups according to the severity of symptoms based on the traditional snakebite severity grading scale. The mild poisoning group (MP) was classified as those who had a grade I snakebite severity during the hospital stay, and the severe poisoning group (SP) was classified as patients who had grade I at the time of admission, but progressed to grade II-IV during hospitalization. Initial clinical manifestations and laboratory findings of the two groups were compared. Results: Bite to hospital time intervals of SP were longer than those of MP (p=0.034), and the local effect score (LES) was higher in SP (p<0.001). Laboratory analyses revealed that creatine phosphokinase (p=0.044), creatine phosphokinase MB isoenzyme (CK-MB, p=0.011) and serum amylase (p=0.008) were significantly higher in SP. LES, CK-MB and serum amylase were significant prognostic predictors as indicated by univariate logistic regression analysis. Multivariate analysis revealed the following two significant predictors: LES (odds ratio=3.983, p<0.001) and serum amylase (odds ratio=1.020, p=0.017). Conclusion: In managing cases of snake bites, clinical manifestations and laboratory findings must be carefully evaluated. LES and serum amylase are predictive factors for severe poisoning, which is especially important to rapid determination of the intensive care of the patient.