• Title/Summary/Keyword: boundaries

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Semi Automatic Building Segmentation using Balloons from 1m Resolution Aerial Images

  • Yoon, Tae-Hun;Kim, Tae-Jung;Lee, Heung-Kyu
    • Proceedings of the KSRS Conference
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    • 1998.09a
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    • pp.246-251
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    • 1998
  • This paper proposes a new building segmentation method from 1m resolution imagery using an Active Contour Model, known as "Balloons". The original balloons, which was designed by Cohen(Cohen, 1991) to extract features from medical images, are modified for building segmentation. The proposed method consists of two phases. Firstly, building boundaries are extracted by balloons with a given position on buildings from an operator. Since balloons actively adjust their shapes according to the boundaries, there is no more shape limitations on detecting buildings. Secondly, buildings are segmented by connecting the corners detected from the building boundaries, because most buildings, which are man-made objects, are effectively described by polygons. The test results show that most buildings are segmented efficiently and easily. The proposed method is new and timely as 1m resolution spaceborne imagery will be available in the very near future. The proposed method can be used fur operational building segmentation from such imagery.

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A Study of the use of allophonic cues in the perception of English word boundaries by Korean learners of English (한국인 영어 학습자의 영어 단어 경계 인지 시 변이음 단서 사용 연구)

  • Chang, Soo-Young;Park, Han-Sang
    • Phonetics and Speech Sciences
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    • v.3 no.3
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    • pp.63-68
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    • 2011
  • This study investigates how Korean students employ acoustic-phonetic cues in perceiving word boundaries of near-homophonous English phrases. For this study, 60 Korean college students participated in the experiment of discriminating word boundaries for 42 pairs of stimuli comprising the allophonic cues of aspiration and glottal stop. Results were analysed in terms of the correctness of responses and the correlation between correctness and confidence. Results showed that stimuli pairs of the glottal stop cue give a higher correctness but those of aspiration a relatively lower correctness. Comparison of the results of this study with those of the previous studies of English and Japanese speakers showed that Korean and Japanese speakers of English give a substantially lower correctness than native speakers of English, while Korean learners of English as a foreign language provide a lower correctness than Japanese speakers of English as a second language.

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Normal Meshes for Multiresolution Analysis on Irregular Meshes with a Boundary (다중해상도해석을 위한 Boundary를 가지는 비정규 메쉬의 Normal 메쉬화 방법)

  • 강성찬;이규열;김태완
    • Korean Journal of Computational Design and Engineering
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    • v.6 no.3
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    • pp.184-192
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    • 2001
  • In this paper we present a remeshing algorithm for irregular meshes with boundaries. The irregular meshes are approximated by regular meshes where the topological regularity is essential for the multiresolutional analysis of the given meshes. Normal meshes are utilized to reduce the necessary data size at each resolution level of the regularized meshes. The normal mesh uses one scalar value, i.e., normal offset value which is based on the regular rule of a uniform subdivision, while other remeshing schemes use one 3D vector at each vertex. Since the normal offset cannot be properly used for the boundaries of meshes, we use a combined subdivision scheme which resolves a problem of the proposed normal offset method at the boundaries. Finally, we show an example to see the effectiveness of the proposed scheme to reduce the data size of a mesh model.

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Generation of 2-D Parametric Surfaces with Highly Irregular Boundaries

  • Sarkar, Subhajit;Dey, Partha Pratim
    • International Journal of CAD/CAM
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    • v.8 no.1
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    • pp.11-20
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    • 2009
  • The conventional methods of boundary-conformed 2D surfaces generation usually yield some problems. This paper deals with two boundary-conformed 2D surface generation methods, one conventional approach, the linear Coons method, and a new method, boundary-conformed interpolation. In this new method, unidirectional 2D surface has been generated using some of the geometric properties of the given boundary curves. A method of simultaneous displacement of the interpolated curves from the opposite boundaries has been adopted. The geometric properties considered for displacements include weighted combination of angle bisector and linear displacement vectors at all the data-points of the two opposite generating curves. The algorithm has one adjustable parameter that controls the characteristics of transformation of one set of curves from its parents. This unidirectional process has been extended to bi-directional parameterization by superimposing two sets of unidirectional curves generated from both boundary pairs. Case studies show that this algorithm gives reasonably smooth transformation of the boundaries. This algorithm is more robust than the linear Coons method and capable of resolving the 2D boundary-conformed parameterization problems.

Extraction and Regularization of Various Building Boundaries with Complex Shapes Utilizing Distribution Characteristics of Airborne LIDAR Points

  • Lee, Jeong-Ho;Han, Soo-Hee;Byun, Young-Gi;Kim, Yong-Il
    • ETRI Journal
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    • v.33 no.4
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    • pp.547-557
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    • 2011
  • This study presents an approach for extracting boundaries of various buildings, which have concave boundaries, inner yards, non-right-angled corners, and nonlinear edges. The approach comprises four steps: building point segmentation, boundary tracing, boundary grouping, and regularization. In the second and third steps, conventional algorithms are improved for more accurate boundary extraction, and in the final step, a new algorithm is presented to extract nonlinear edges. The unique characteristics of airborne light detection and ranging (LIDAR) data are considered in some steps. The performance and practicality of the presented algorithm were evaluated for buildings of various shapes, and the average omission and commission error of building polygon areas were 0.038 and 0.033, respectively.

Micro-electrochemical Characteristics of Sensitized 304 Stainless steel Using Micro-droplet cell Techniques (마이크로 드로플릿 셀 기법을 이용한 예민화 된 304 스테인리스강의 미세전기화학 특성)

  • Kim, Kyu-Seop;Lee, Jae-Bong
    • Corrosion Science and Technology
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    • v.9 no.6
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    • pp.300-309
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    • 2010
  • The influences of sensitization on localized corrosion resistance of 304 stainless steel, were investigated, using micro-dropletcell techniques. Micro-droplet cell allows one to align the micro-electrode to the desired spot of the working electrode and measure directly local current with the potentiodynamic polarization, linear polarization and a.c. impedance. Micro-electrochemical tests were carried out inside of the grain and on grain boundaries separately. It was found that sensitization decreased the pitting potential, increasing corrosion current density around grain boundaries. Galvanic current density was also measured between grain and grain boundaries.

A Modified Viterbi Algorithm for Word Boundary Detection Error Compensation (단어 경계 검출 오류 보정을 위한 수정된 비터비 알고리즘)

  • Chung, Hoon;Chung, Ik-Joo
    • The Journal of the Acoustical Society of Korea
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    • v.26 no.1E
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    • pp.21-26
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    • 2007
  • In this paper, we propose a modified Viterbi algorithm to compensate for endpoint detection error during the decoding phase of an isolated word recognition task. Since the conventional Viterbi algorithm explores only the search space whose boundaries are fixed to the endpoints of the segmented utterance by the endpoint detector, the recognition performance is highly dependent on the accuracy level of endpoint detection. Inaccurately segmented word boundaries lead directly to recognition error. In order to relax the degradation of recognition accuracy due to endpoint detection error, we describe an unconstrained search of word boundaries and present an algorithm to explore the search space with efficiency. The proposed algorithm was evaluated by performing a variety of simulated endpoint detection error cases on an isolated word recognition task. The proposed algorithm reduced the Word Error Rate (WER) considerably, from 84.4% to 10.6%, while consuming only a little more computation power.

The Types and Management of Differentiating Consumption depends on the social class of Korean consumers

  • LEE, Jaemin
    • Journal of Wellbeing Management and Applied Psychology
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    • v.2 no.1
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    • pp.35-39
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    • 2019
  • This paper presents two social and academic studies on the boundary between cultural production and consumption. The first line of the study on cultural omnivore analyzes the choice of heterogeneous audiences in the face of various cultural offerings. The second line is a study of market categories, which analyzes the responses of peer audiences to objects with different levels of category code compliance. As such, this paper developed a heterogeneous audience model to evaluate objects of different types. This allows us to consider two dimensions of cultural preference: diversity and orientation of selection. To this end, this paper proposes a new analytical frame work to map consumption behavior on these two dimensions. The results suggest that one type of target that values diversity and transformation is particularly resistant to those that span boundaries. We test this argument in the analysis of two large data sets on film and restaurant reviews. Overall, our findings can extend beyond cultural consumption. Outline variability of contextual individuals or individuals in the same situation can cross cultural boundaries even if they are not intentionally pursuing such hybridism.

An Adaptive Post-processing Method for Improving Quality of Highly Compressed Video (고압축 비디오의 화질향상을 위한 적응적 후처리 기법)

  • 김종호;정제창
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.53 no.8
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    • pp.611-614
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    • 2004
  • In this paper, we propose an adaptive blocking artifact reduction algorithm using characteristics of the block boundaries. Blocking artifacts contain the high frequency components near the block boundaries, so the lowpass filtering can remove them. But a simple lowpass filtering results into blurring by remove important features such as edges. To overcome this problem, we determine the modes depending on the characteristics around boundaries then proper filter is applied to each area. Simulation results show that the proposed method improves deblocking performance compared to that of MPEG-4.

Electrical and Chemical Characteristics of the Grain Boundaries of Semiconducting $BaTiO_3$ Ceramics Prepared with Surface-Coated Powders (표면 코팅된 분말을 이용하여 제조된 반도성 $BaTiO_3$ 소결체의 입계 화학 및 전기적 특성)

  • 박명범;김정돈;조남희
    • Journal of the Korean Ceramic Society
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    • v.37 no.4
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    • pp.338-344
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    • 2000
  • Grain boundary chemistry and electrical characteristics of polycrystalline BaTiO3 ceramics, which were prepared with sol-gel surface-coated semiconducting powders, were investigated. Mn ions were coated on the powder surface by sol-gel coating-techniques. The additives coated on the surface of the powders were observed to be present near the grain boundaries of the ceramics. The ceramics exhibit the PTCR characteristics with a resistivity jump ratio(Pmax/Pmin) of about 2$\times$103. With raising the temperature from room temprature to 20$0^{\circ}C$, the oxidation state of the Mn ions varied from Mn3+ to Mn2+ in the coating layers. Near the grain boundaries an excessive negative charge layer of about 20nm was formed.

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