• Title/Summary/Keyword: complex segment

Search Result 174, Processing Time 0.024 seconds

Development of Exit Burr Identification Algorithm on Multiple Feature Workpiece and Multiple Tool Path (복합형상 및 다중경로에 대한 Exit Burr 판별 알고리듬의 개발- 스플라인을 포함한 Exit Burr의 해석 -)

  • Kim, Ji-Hwan;Lee, Jang-Beom;Kim, Young-Jin
    • IE interfaces
    • /
    • v.18 no.3
    • /
    • pp.247-252
    • /
    • 2005
  • In the automated production environment in the present days, the minimization of manual operation becomes a very important factor in increasing the efficiency of the production system. The exit burr produced through the milling operation on the edge of workpiece usually requires manual deburring process to enhance the level of precision of the resulting product. So far, researchers have developed various methods to understand the formation of exit burr in cutting process. One method to analytically identify the formation of exit burr was to use the geometrical information of CAD and CAM data used in automated machining. This method, in turn, generated the information resulting from the analysis such as burr type, cutting region, and exit angle. Up to now, the geometrical data were restricted to the single feature and single path. In this paper, a method to deal with the complicated geometric features such as line segment, arc, hole, and spline will be presented and validated using the field data. This method also deals with the complex workpiece shape which is a combination of multiple features. As for the cutting path, multiple tool path is analyzed in order to simulate the real cutting process. All this analysis is combined into a Windows based software and real data are used to validate the program in the conclusion.

Implementation of FlexRay Network System using Node-based Scheduling Method (노드 기반 스케줄링 방법을 이용한 FlexRay 네트워크 시스템의 구현)

  • Kim, Man-Ho;Ha, Kyoung-Nam;Lee, Suk;Lee, Kyung-Chang
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.18 no.2
    • /
    • pp.39-47
    • /
    • 2010
  • As vehicles become intelligent for convenience and safety of drivers, in-vehicle networking (IVN) systems are essential components of intelligent vehicles. Recently, the chassis networking system which require increased network capacity and real-time capability is being developed to expand the application area of IVN systems. Also, FlexRay has been developed for the chassis networking system. However, FlexRay needs a complex scheduling method of static segment, which is a barrier for implementing the chassis networking system. Especially, if we want to migrate from CAN network to FlexRay network using CAN message database that was well constructed for the chassis networking system by automotive vendors, a novel scheduling method is necessary to be able to reduce design complexity. This paper presents a node-based scheduling method for FlexRay network system. And, in order to demonstrate the method's feasibility, its performance is evaluated through an experimental testbed.

Contents and Channel Operations for Over-the-Air Digital Broadcasting (지상파 디지털방송의 콘텐츠와 채널운영)

  • Ha, Ju-Yong;Ryu, Seung-Kwan
    • The Journal of the Korea Contents Association
    • /
    • v.8 no.5
    • /
    • pp.176-183
    • /
    • 2008
  • The transition to digital television is a massive and complex undertaking, affecting virtually every segment of the television industry and all viewers who watch television. In this respect, consequences of digital conversion of broadcasting and its related industries are so tremendous that countermeasure establishment for activation of digital broadcasting and programming industry is required. This paper explores the current situation of digital broadcasting in terms of the channel operation and contents focusing on the cases of the U.S. and U.K. In doing so, this paper presents reasonable directions and policy suggestions that should be resolved to advance Korean digital broadcasting.

Segmentation of Computed Tomography using The Geometric Active Contour Model (기하학적 동적 외곽선 모델을 이용한 X-ray 단층촬영영상의 영상추출)

  • Jang, D.P.;Kim, S.I.
    • Proceedings of the KOSOMBE Conference
    • /
    • v.1997 no.11
    • /
    • pp.541-545
    • /
    • 1997
  • This paper presents a modified geometric active contour model or edge detection and segmentation of computed tomography(CT) scan images. The method is based on the level setup approach developed by Osher and Sethian and the modeling of propagation fronts with curvature dependent speeds by Malladi. Based on above algorithms, the geometric active contour is obtained through a particular level set of hypersurface lowing along its gradient force and curvature force. This technique retains the attractive feature which is topological and geometric flexibility of the contour in recovering objects with complex shapes and unknown topologies. But there are limitations in this algorithm which are being not able to separate the object with weak difference from neighbor object. So we use speed limitation filter to overcome those problems. We apply a 2D model to various synthetic cases and the three cases of real CT scan images in order to segment objects with complicated shapes and topologies. From the results, the presented model confirms that it attracts very naturally and efficiently to the desired feature of CT scan images.

  • PDF

Molecular Characterization of a Novel Putative Partitivirus Infecting Cytospora sacchari, a Plant Pathogenic Fungus

  • Peyambari, Mahtab;Habibi, Mina Koohi;Fotouhifar, Khalil-Berdi;Dizadji, Akbar;Roossinck, Marilyn J.
    • The Plant Pathology Journal
    • /
    • v.30 no.2
    • /
    • pp.151-158
    • /
    • 2014
  • Three double-stranded RNAs (dsRNAs), approximately 1.85, 1.65 and 1.27 kb in size, were detected in an isolate of Cytospora sacchari from Iran. Partial nucleotide sequence revealed a 1,284 bp segment containing one ORF that potentially encodes a 405 aa protein. This protein contains conserved motifs related to RNA dependent RNA polymerases (RdRp) that showed similarity to RdRps of partitiviruses. The results indicate that these dsRNAs represent a novel Partitivirus that we tentatively designate Cytospora sacchari partitivirus (CsPV). Treatment of the fungal strain by cyclohexamide and also hyphal tip culture had no effect on removing the putative virus. Phylogenetic analysis of putative RdRp of CsPV and other partitiviruses places CsPV as a member of the genus Partitivirus in the family Partitiviridae, and clustering with Aspergillus ochraceous virus 1.

An Effective Orientation-based Method and Parameter Space Discretization for Defined Object Segmentation

  • Nguyen, Huy Hoang;Lee, GueeSang;Kim, SooHyung;Yang, HyungJeong
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.7 no.12
    • /
    • pp.3180-3199
    • /
    • 2013
  • While non-predefined object segmentation (NDOS) distinguishes an arbitrary self-assumed object from its background, predefined object segmentation (DOS) pre-specifies the target object. In this paper, a new and novel method to segment predefined objects is presented, by globally optimizing an orientation-based objective function that measures the fitness of the object boundary, in a discretized parameter space. A specific object is explicitly described by normalized discrete sets of boundary points and corresponding normal vectors with respect to its plane shape. The orientation factor provides robust distinctness for target objects. By considering the order of transformation elements, and their dependency on the derived over-segmentation outcome, the domain of translations and scales is efficiently discretized. A branch and bound algorithm is used to determine the transformation parameters of a shape model corresponding to a target object in an image. The results tested on the PASCAL dataset show a considerable achievement in solving complex backgrounds and unclear boundary images.

LiDAR Image Segmentation using Convolutional Neural Network Model with Refinement Modules (정제 모듈을 포함한 컨볼루셔널 뉴럴 네트워크 모델을 이용한 라이다 영상의 분할)

  • Park, Byungjae;Seo, Beom-Su;Lee, Sejin
    • The Journal of Korea Robotics Society
    • /
    • v.13 no.1
    • /
    • pp.8-15
    • /
    • 2018
  • This paper proposes a convolutional neural network model for distinguishing areas occupied by obstacles from a LiDAR image converted from a 3D point cloud. The channels of a LiDAR image used as input consist of the distances to 3D points, the reflectivities of 3D points, and the heights of 3D points from the ground. The proposed model uses a LiDAR image as an input and outputs a result of a segmented LiDAR image. The proposed model adopts refinement modules with skip connections to segment a LiDAR image. The refinement modules with skip connections in the proposed model make it possible to construct a complex structure with a small number of parameters than a convolutional neural network model with a linear structure. Using the proposed model, it is possible to distinguish areas in a LiDAR image occupied by obstacles such as vehicles, pedestrians, and bicyclists. The proposed model can be applied to recognize surrounding obstacles and to search for safe paths.

Robust Segmentation for Low Quality Cell Images from Blood and Bone Marrow

  • Pan Chen;Fang Yi;Yan Xiang-Guo;Zheng Chong-Xun
    • International Journal of Control, Automation, and Systems
    • /
    • v.4 no.5
    • /
    • pp.637-644
    • /
    • 2006
  • Biomedical image is often complex. An applied image analysis system should deal with the images which are of quite low quality and are challenging to segment. This paper presents a framework for color cell image segmentation by learning and classification online. It is a robust two-stage scheme using kernel method and watershed transform. In first stage, a two-class SVM is employed to discriminate the pixels of object from background; where the SVM is trained on the data which has been analyzed using the mean shift procedure. A real-time training strategy is also developed for SVM. In second stage, as the post-processing, local watershed transform is used to separate clustering cells. Comparison with the SSF (Scale space filter) and classical watershed-based algorithm (those are often employed for cell image segmentation) is given. Experimental results demonstrate that the new method is more accurate and robust than compared methods.

Line Segment Detection Algorithm Using Improved PPHT (개선된 PPHT를 이용한 선분 인식 알고리즘)

  • Lee, Chanho;Moon, Ji-hyun;Nguyen, Duy Phuong
    • Journal of IKEEE
    • /
    • v.20 no.1
    • /
    • pp.82-88
    • /
    • 2016
  • The detection rate of Progressive Probability Hough Transform(PPHT) is decreased when a lot of noise components exist due to an unclear or complex original image although it is quite a good algorithm that detects line segments accurately. In order to solve the problem, we propose an improved line detecting algorithm which is robust to noise components and recovers slightly damaged edges. The proposed algorithm is based on PPHT and traces a line segments by pixel and checks of it is straight. It increases the detection rate by reducing the effect of noise components and by recovering edge patterns within a limited pixel size. The proposed algorithm is applied to a lane detection method and the false positive detection rate is decreased by 30% and the line detection rate is increased by 15%.

Bilateral cleft lip (양측성 구순열)

  • Kim, Jong-Ryoul
    • Korean Journal of Cleft Lip And Palate
    • /
    • v.10 no.1
    • /
    • pp.39-56
    • /
    • 2007
  • The bilateral cleft lip, a more severe form of clefting than unilateral cleft lip, involves separation of the lip along philtral lines, isolating the central segment (prolabium). Bilateral cleft lip may be either symmetrical or asymmetrical, in which case the cleft lip is split more on one side than on the other. The cleft affects the obvious facial form as an anatomic deformity and has functional consequences, affecting the child's ability to eat, speak, hear, and breathe. Although there would seem to be quite a variance in reported figures, ratios of cleft lip with or without cleft palate have gone as high as 1:500 and as low as 1:1000. It is known that less than 10% of cleft lips are bilateral. Although bilateral cleft lip is less common than unilateral cleft lip, the deformity is more severe, and the reconstructive technique is more complex. Surgery is the only treatment necessary for patients with bilateral cleft lip. Accompanying the evolution of surgical repair is the increasingly important role of orthodontic support with early presurgical alveolar and nasal molding. Repositioning the maxillary and alveolar segments into a more anatomic position allows the surgeon to repair the lip and associated nasal deformity under more optimal conditions. The purpose of this article is to review the related anatomy, presurgical management, and surgical management of bilateral cleft lip.

  • PDF