• 제목/요약/키워드: Line-based

검색결과 10,017건 처리시간 0.037초

유한요소 역해석을 이용한 복잡한 자동차 판넬의 트리밍 라인 설계 (Trimming Line Design of Auto-body Panel with Complex Shape Using Finite Element Inverse Method)

  • 송윤준;한영호;박춘달;정완진
    • 소성∙가공
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    • 제15권6호
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    • pp.459-466
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    • 2006
  • Trimming line design plays an important role in obtaining accurate edge profile after flanging. Compared to the traditional section-based method, simulation-based method can produce more accurate trimming line by considering deformation mechanics. Recently, the use of a finite element inverse method is proposed to obtain optimal trimming line. By analyzing flanging inversely from the final mesh after flanging, trimming line can be obtained from initial mesh on the drawing die surface. Initial guess generation fer finite element inverse method is obtained by developing the final mesh onto drawing tool mesh. Incremental development method is adopted to handle irregular mesh with various size and undercut. In this study, improved incremental development algorithm to handle complex shape is suggested. When developing the final mesh layer by layer, the algorithm which can define the development sequence and the position of developing nodes is thoroughly described. Flanging of front fender is analyzed to demonstrate the effectiveness of the present method. By using section-based trimming line and simulation-based trimming line, incremental finite element simulations are carried out. In comparison with experiment, it is clearly shown that the present method yields more accurate edge profile than section-based method.

공통 아키텍처 기반 제품계열 아키텍처 설계 (Design of Product-Line Architecture based-on Common Architecture)

  • 오영배;신성욱;김영갑;백두권
    • 한국IT서비스학회지
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    • 제5권2호
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    • pp.155-168
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    • 2006
  • Software product line is a software product or a set of software system, which has common functions. We can develop a specific software product, which satisfies requirements of a particular market segment and a mission in a specific domain by reusing the core asset such as the developed software architecture through the software product line. Software development methodology based on the software product line can develop a software more easily and fast by reusing the developed software core asset. Developed countries of software technology select software product line as a core field of software production technology, and support technology development. In case of USA, CMU/SEI(Carnegie Mellon University/Software Engineering Institute) developed product-line framework 4.0 together with the industry and the Department of Defense. Europe is supporting the development of product line technology through ITEA(IT for European Advancement) program. However, industries in our country understand the necessity of software production technology based on product line concept for the purpose of increasing productivity, it is not sufficient to invest for this technology development. In this paper, we aim to construct the common architecture of software product line for production of the software product line.

Line feature extraction in a noisy image

  • Lee, Joon-Woong;Oh, Hak-Seo;Kweon, In-So
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1996년도 Proceedings of the Korea Automatic Control Conference, 11th (KACC); Pohang, Korea; 24-26 Oct. 1996
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    • pp.137-140
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    • 1996
  • Finding line segments in an intensity image has been one of the most fundamental issues in computer vision. In complex scenes, it is hard to detect the locations of point features. Line features are more robust in providing greater positional accuracy. In this paper we present a robust "line features extraction" algorithm which extracts line feature in a single pass without using any assumptions and constraints. Our algorithm consists of five steps: (1) edge scanning, (2) edge normalization, (3) line-blob extraction, (4) line-feature computation, and (5) line linking. By using edge scanning, the computational complexity due to too many edge pixels is drastically reduced. Edge normalization improves the local quantization error induced from the gradient space partitioning and minimizes perturbations on edge orientation. We also analyze the effects of edge processing, and the least squares-based method and the principal axis-based method on the computation of line orientation. We show its efficiency with some real images.al images.

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Electromagnetic Environment of Transmission Line Based on Full Parameter Online Estimation

  • Sun, Zidan;Zhou, Xiaofeng;Liang, Likai;Mo, Yang
    • Journal of Information Processing Systems
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    • 제16권2호
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    • pp.394-405
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    • 2020
  • The parameters of transmission lines have an influence on the electromagnetic environment surrounding the line. This paper proposes a method based on phasor measurement unit (PMU) and supervisory control and data acquisition (SCADA) to achieve online estimation of transmission line full parameters, such as resistance, reactance and susceptance. The proposed full parameter estimation method is compared with the traditional method of estimating resistance independently based on SCADA system. Then, the electromagnetic environment is analyzed based on the different parameter estimation methods. The example results illustrate that online estimation of transmission line full parameters is more accurate in the analysis of electromagnetic environment, which further confirms its necessity and significance in engineering application.

A Consistent Quality Bit Rate Control for the Line-Based Compression

  • Ham, Jung-Sik;Kim, Ho-Young;Lee, Seong-Won
    • IEIE Transactions on Smart Processing and Computing
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    • 제5권5호
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    • pp.310-318
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    • 2016
  • Emerging technologies such as the Internet of Things (IoT) and the Advanced Driver Assistant System (ADAS) often have image transmission functions with tough constraints, like low power and/or low delay, which require that they adopt line-based, low memory compression methods instead of existing frame-based image compression standards. Bit rate control in the conventional frame-based compression systems requires a lot of hardware resources when the scope of handled data falls at the frame level. On the other hand, attempts to reduce the heavy hardware resource requirement by focusing on line-level processing yield uneven image quality through the frame. In this paper, we propose a bit rate control that maintains consistency in image quality through the frame and improves the legibility of text regions. To find the line characteristics, the proposed bit rate control tests each line for ease of compression and the existence of text. Experiments on the proposed bit rate control show peak signal-to-noise ratios (PSNRs) similar to those of conventional bit rate controls, but with the use of significantly fewer hardware resources.

Analysis of slope stability based on evaluation of force balance

  • Razdolsky, A.G.;Yankelevsky, D.Z.;Karinski, Y.S.
    • Structural Engineering and Mechanics
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    • 제20권3호
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    • pp.313-334
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    • 2005
  • The paper presents a new approach for the analysis of slope stability that is based on the numerical solution of a differential equation, which describes the thrust force distribution within the potential sliding mass. It is based on the evaluation of the thrust force value at the endpoint of the slip line. A coupled approximation of the slip and thrust lines is applied. The model is based on subdivision of the sliding mass into slices that are normal to the slip line and the equilibrium differential equation is obtained as the slice width approaches zero. Opposed to common iterative limit equilibrium procedures the present method is straightforward and gives an estimate of slope stability at the value of the safety factor prescribed in advance by standard requirements. Considering the location of the thrust line within the soil mass above the trial slip line eliminates the possible development of a tensile thrust force in the stable and critical states of the slope. The location of the upper boundary point of the thrust line is determined by the equilibrium of the upper triangular slice. The method can be applied to any smooth shape of a slip line, i.e., to a slip line without break points. An approximation of the slip and thrust lines by quadratic parabolas is used in the numerical examples for a series of slopes.

시각을 이용한 이동 로봇의 강건한 경로선 추종 주행 (Vision-Based Mobile Robot Navigation by Robust Path Line Tracking)

  • 손민혁;도용태
    • 센서학회지
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    • 제20권3호
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    • pp.178-186
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    • 2011
  • Line tracking is a well defined method of mobile robot navigation. It is simple in concept, technically easy to implement, and already employed in many industrial sites. Among several different line tracking methods, magnetic sensing is widely used in practice. In comparison, vision-based tracking is less popular due mainly to its sensitivity to surrounding conditions such as brightness and floor characteristics although vision is the most powerful robotic sensing capability. In this paper, a vision-based robust path line detection technique is proposed for the navigation of a mobile robot assuming uncontrollable surrounding conditions. The technique proposed has four processing steps; color space transformation, pixel-level line sensing, block-level line sensing, and robot navigation control. This technique effectively uses hue and saturation color values in the line sensing so to be insensitive to the brightness variation. Line finding in block-level makes not only the technique immune from the error of line pixel detection but also the robot control easy. The proposed technique was tested with a real mobile robot and proved its effectiveness.

소실점 정보의 Loss 함수를 이용한 특징선 기반 SLAM (Line-Based SLAM Using Vanishing Point Measurements Loss Function)

  • 임현준;명현
    • 로봇학회논문지
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    • 제18권3호
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    • pp.330-336
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    • 2023
  • In this paper, a novel line-based simultaneous localization and mapping (SLAM) using a loss function of vanishing point measurements is proposed. In general, the Huber norm is used as a loss function for point and line features in feature-based SLAM. The proposed loss function of vanishing point measurements is based on the unit sphere model. Because the point and line feature measurements define the reprojection error in the image plane as a residual, linear loss functions such as the Huber norm is used. However, the typical loss functions are not suitable for vanishing point measurements with unbounded problems. To tackle this problem, we propose a loss function for vanishing point measurements. The proposed loss function is based on unit sphere model. Finally, we prove the validity of the loss function for vanishing point through experiments on a public dataset.

A Boundary Protection for Power Distribution Line Based on Equivalent Boundary Effect

  • Zhang, Xin;Mu, Long-Hua
    • Journal of Electrical Engineering and Technology
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    • 제8권2호
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    • pp.262-270
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    • 2013
  • A boundary protection method for power distribution line based on equivalent boundary effect is presented in this paper. In the proposed scheme, the equivalent resonance component with a certain central frequency is sleeve-mounted at the beginning of protected zone. The 'Line Boundary' is built by using boundary effect, which is created by introducing impedance in the primary-side of line. The 'Line Boundary' is significantly different from line wave impedance. Therefore, the boundary protection principle can be applied to power distribution line without line traps. To analyze the frequency characteristic corresponding to traveling-waves of introducing impedance in the primary-side of line, distributed parameters model of equivalent resonance component is established. The results of PSCAD/EMTDC simulation prove the obvious difference of voltage high frequency component between internal faults and external faults due to equivalent resonance component, and validate the scheme.

Irinotecan as a Second-line Chemotherapy for Small Cell Lung Cancer: a Systemic Analysis

  • Zhang, Ming-Qian;Lin, Xin;Li, Yan;Lu, Shuang
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권5호
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    • pp.1993-1995
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    • 2015
  • Purpose: This analysis was conducted to evaluate the efficacy and safety of irinotecan based regimens as second-line chemotherapy in treating patients with small cell lung cancer. Methods: Clinical studies evaluating the efficacy and safety of irinotecan based regimens as second-line chemotherapy for patients with small cell lung cancer were identified using a predefined search strategy. Pooled response rates (RRs) of treatment were calculated. Results: In irinotecan based regimens as second-line chemotherapy, 4 clinical studies which including 155 patients with small cell lung cancer were considered eligible for inclusion. In all chemotherapy consisted of irinotecan with or without nedaplatin. Pooled analysis suggested that, in all patients, the pooled RR was 27.1% (42/155) in irinotecan based regimens. Nausea, vomiting, diarrhea and myelosuppression were the main side effects. No grade III or IV renal or liver toxicity was observed. No treatment related death occurred with the irinotecan based treatments. Conclusion: This systemic analysis suggests that irinotecan based regimens as second-line chemotherapy are associated with mild response rate and acceptable toxicity for patients with small cell lung cancer.