• Title/Summary/Keyword: size and scale

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TFT-LCD Defect Detection Using Mean Difference Between Local Regions Based on Multi-scale Image Reconstruction (로컬 영역 간 평균 화소값 차를 이용한 멀티스케일 기반의 TFT-LCD 결함 검출)

  • Jung, Chang-Do;Lee, Seung-Min;Yun, Byoung-Ju;Lee, Joon-Jae;Choi, Il;Park, Kil-Houm
    • Journal of Korea Multimedia Society
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    • v.15 no.4
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    • pp.439-448
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    • 2012
  • TFT-LCD panel images have non-uniform brightness, noise signal and defect signal. It is hard to divide defect signal because of non-uniform brightness and noise signal, so various divide methods have being developed. In this paper, we suggest method to divide defective regions on TFT-LCD panel image by estimating a menas of two different size of windows, which is suggested by Eikvil et al., and using difference of them. But in this method, the size of detectable defects is restricted by the size of window, hence it has inefficient problem that the size of window have to increase to divide a large defect region. To solve this problem we suggest an algorithm which can divide various size of defects, by using Multi-scale and restrict a detectable size of defects in each scale. To prove an efficiency of suggested algorithm, we show that resulting images of real TFT-LCD panel images and an artificial image with various defects.

Strength Analysis of Particle-Reinforced Composites with Length-Scale Effect based on Geometrically Necessary Dislocations (기하적 필수 전위에 의한 길이효과를 고려한 입자 강화 복합재의 강도해석)

  • Suh, Y.S.;Joshi, Shailendra P.;Ramesh, K.T.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2009.05a
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    • pp.322-325
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    • 2009
  • An enhanced continuum model for the size dependent strengthening of particle reinforced composites is presented. The model accounts explicitly for the enhanced strength in a discretely defined "punched zone" around the particle in a metal matrix composite as a result of geometrically necessary dislocations developed through a CTE mismatch. The size of the punched zone presents an intrinsic length scale, and this results in the size dependence of the overall behavior of the composite. Results show that predicted 0.2% offset yield stresses are increasing with smaller inclusions and larger volume fractions and this length-scale effect on the enhanced strength can be observed by explicitly including GND region around the particle.

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Two scale modeling of behaviors of granular structure: size effects and displacement fluctuations of discrete particle assembly

  • Chu, Xihua;Yu, Cun;Xiu, Chenxi;Xu, Yuanjie
    • Structural Engineering and Mechanics
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    • v.55 no.2
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    • pp.315-334
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    • 2015
  • This study's primary aim is to check the existence of a representative volume element for granular materials and determine the link between the properties (responses) of macro structures and the size of the discrete particle assembly used to represent a constitutive relation in a two-scale model. In our two-scale method the boundary value problem on the macro level was solved using finite element method, based on the Cosserat continuum; the macro stresses and modulus were obtained using a solution of discrete particle assemblies at certain element integration points. Meanwhile, discrete particle assemblies were solved using discrete element method under boundary conditions provided by the macro deformation. Our investigations focused largely on the size effects of the discrete particle assembly and the radius of the particle on macro properties, such as deformation stiffness, bearing capacity and the residual strength of the granular structure. According to the numerical results, we suggest fitting formulas linking the values of different macro properties (responses) and size of discrete particle assemblies. In addition, this study also concerns the configuration and displacement fluctuation of discrete particle assemblies on the micro level, accompanied with the evolution of bearing capacity and deformation on the macro level.

Efficiency and Returns to Scale in the Bangladesh Banking Sector: Empirical Evidence from the Slack-Based DEA Method

  • Sufian, Fadzlan;Kamarudin, Fakarudin
    • Asia-Pacific Journal of Business
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    • v.5 no.1
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    • pp.1-11
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    • 2014
  • The study provides new empirical evidence on the level of profit efficiency and returns to scale of the Bangladesh banking sector. We employ the Slack-Based Data Envelopment Analysis (SBM-DEA) method to assess the level of profit efficiency of individual banks over the years 2004 to 2011. The empirical findings indicate that the Bangladesh banking sector has exhibited the highest and lowest level of profit efficiency during years 2004 and 2011 respectively. We find that only eight banks have been profit efficient throughout the period under study. The empirical findings seem to suggest that most of the Bangladesh banks have been experiencing economies of scale due to being at less than the optimum size, or diseconomies of scale due to being at more than the optimum size. Thus, decreasing or increasing the scale of production could result in cost savings or efficiencies.

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Investigation of the effects of particle size and model scale on the UCS and shear strength of concrete using PFC2D

  • Haeri, Hadi;Sarfarazi, Vahab;Zhu, Zheming;Lazemi, Hossein Ali
    • Structural Engineering and Mechanics
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    • v.67 no.5
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    • pp.505-516
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    • 2018
  • In this paper, the effects of particle size and model scale of concrete has been investigated on the failure mechanism of PFC2D numerical models under uniaxial compressive test. For this purpose, rectangular models with same particle sizes and different model dimensions, i.e., $3mm{\times}6mm$, $6mm{\times}12mm$, $12mm{\times}24mm$, $25mm{\times}50mm$ and $54mm{\times}108mm$, were prepared. Also rectangular models with dimension of $54mm{\times}108mm$ and different particle sizes, i.e., 0.27 mm, 0.47 mm, 0.67 mm, 0.87 mm, 1.07 mm, 1.87 mm and 2.27 mm were simulated using PFC2D and tested under uniaxial compressive test. Concurrent with uniaxial test, direct shear test was performed on the numerical models. Dimension of the models were $75{\times}100mm$. Two narrow bands of particles with dimension of $37.5mm{\times}20mm$ were removed from upper and lower of the model to supply the shear test condition. The particle sizes in the models were 0.47 mm, 0.57 mm, 0.67 mm and 0.77 mm. The result shows that failure pattern was affected by model scale and particle size. The uniaxial compressive strength and shear strength were increased by increasing the model scale and particle size.

Wind tunnel tests on flow fields of full-scale railway wind barriers

  • Su, Yang;Xiang, Huoyue;Fang, Chen;Wang, Lei;Li, Yongle
    • Wind and Structures
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    • v.24 no.2
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    • pp.171-184
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    • 2017
  • The present study provides a deeper understanding of the flow fields of a full-scale railway wind barriers by means of a wind tunnel test. First, the drag forces of the three wind barriers were measured using a force sensor, and the drag force coefficients were compared with a similar scale model. On this basis, the mean wind velocity and turbulence upwind and downwind of the wind barriers were measured. The effects of pore size and opening forms of the wind barrier were discussed. The results show that the test of the scaled wind barrier model may be unsafe, and it is suitable to adopt the full-scale wind barrier model. The pore size and the opening forms of wind barriers have a slight influence on the flow fields upwind of the wind barrier but have some influences on the flow fields and power spectra downwind of the wind barrier. The smaller pore size generates a lower turbulence density and value of the power spectrum near the wind barrier, and the porous wind barriers clearly provide better shelter than the bar-type wind barriers.

A Study on the size of the school rationalization orientation considering the local characteristics (지역특성을 고려한 학교규모 적정화 방향 설정에 관한 연구)

  • Lee, Sang-Min;Cho, Chang-Hee
    • The Journal of Sustainable Design and Educational Environment Research
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    • v.15 no.1
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    • pp.40-48
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    • 2016
  • School appropriate scale refers to the size of the school to minimize students' educational deficits and ensure an appropriate level of students, the number of classes, class size, etc., and maximize educational effects. Difficult set of absolute standards appropriate scale school, contemporary social situations and educational effects, and seek a comprehensive and reasonable direction, considering this is required. School appropriate scale it is preferable to consider the effect of conditions in areas such as education, curriculum, but it is common to set the range in terms of school operational effectiveness, and efficiency of education funding, school environment. So the concept of the appropriate scale including the school's status changes associated with school size, is seeking a new direction is needed so that the school environment, etc. are considered.

A Study on the Size of 2D Iris Codes for Personal Identification (신분인식을 위한 2D 홍채코드 크기에 관한 연구)

  • Joo, Sang-Hyun;Yang, Woo-Suk
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.11 no.2
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    • pp.113-118
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    • 2011
  • This paper has analyzed recognizing performance depending on the size of iris codes extracting by iris recognition algorithm using scale-space filtering. The iris images were created through pre-processing, the features were extracted by scale-space filtering, and the codes of 16 sizes were generated. The generated code's performance was compared for each code to calculate FAR and FRR by matching method utilizing Hamming distance. Every code had little overlapping portion between same person and other persons group so that the proposed algorithm's superiority was proved, and the performance of iris codes was analyzed for each size focused on convenience to use when implementing in realization. In addition, the iris codes suitable to iris recognition system that is high-reliable and is able to reduce user's inconvenience due to mis-rejection has been presented considering for commercialization.

A Study on the Effects of Regional Context on Entrepreneurial Orientation (지역적 맥락이 기업가 지향성에 미치는 영향)

  • Kim, Sunwoo;Kim, Moon Sun
    • Journal of Korean Society for Quality Management
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    • v.47 no.4
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    • pp.847-859
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    • 2019
  • Purpose: The companies must be located in the area, scale up, create jobs, and return to the local economy. This paper attempted to analyze empirically the relationship between regional context and entrepreneurial orientation(EO) in the region of Korea. Methods: This paper analyzed survey data and regional statistics. We measured EO by region and then examined which regional context affect EO. Regional contexts were measured by population, economic size, budget size, firm size, innovation capacity, and education level. EO was measured by innovativeness, risk taking, proactiveness, autonomy, competitive aggressiveness, and need for achievement. Results: EO was high in the region where the budget size per thousand population, the number of manufacturers per thousand population, the number of new corporations per thousand population, the number of R&D personnel per thousand population, and the number of students of higher education institutions per thousand population were high. Conclusion: The implications of this paper are that regional context affect EO, and there are differences in budget scale, firm size, innovation capacity, and education level. In regions with many investment resources for innovation and startups and manufacturers, the number of R&D personnel and students of higher education institutions (future R&D personnel), in particular, determines EO.

Size Aware Correlation Filter Tracking with Adaptive Aspect Ratio Estimation

  • Zhu, Xiaozhou;Song, Xin;Chen, Xiaoqian;Bai, Yuzhu;Lu, Huimin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.2
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    • pp.805-825
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    • 2017
  • Correlation Filter-based Trackers (CFTs) gained popularity recently for their effectiveness and efficiency. To deal with the size changes of the target which may degenerate the tracking performance, scale estimation has been introduced in existing CFTs. However, the variations of the aspect ratio were usually neglected, which also influence the size of the target. In this paper, Size Aware Correlation Filter Trackers (SACFTs) are proposed to deal with this problem. The SACFTs not only determine the translation and scale variations, but also take the aspect ratio changes into consideration, thus a better estimation of the size of the target can be realized, which improves the overall tracking performance. And competing results can be achieved compared with state-of-the-art methods according to the experiments conducted on two large scale datasets.