• Title/Summary/Keyword: Local feature

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Real-time Traffic Sign Recognition using Rotation-invariant Fast Binary Patterns (회전에 강인한 고속 이진패턴을 이용한 실시간 교통 신호 표지판 인식)

  • Hwang, Min-Chul;Ko, Byoung Chul;Nam, Jae-Yeal
    • Journal of Broadcast Engineering
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    • v.21 no.4
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    • pp.562-568
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    • 2016
  • In this paper, we focus on recognition of speed-limit signs among a few types of traffic signs because speed-limit sign is closely related to safe driving of drivers. Although histogram of oriented gradient (HOG) and local binary patterns (LBP) are representative features for object recognition, these features have a weakness with respect to rotation, in that it does not consider the rotation of the target object when generating patterns. Therefore, this paper propose the fast rotation-invariant binary patterns (FRIBP) algorithm to generate a binary pattern that is robust against rotation. The proposed FRIBP algorithm deletes an unused layer of the histogram, and eliminates the shift and comparison operations in order to quickly extract the desired feature. The proposed FRIBP algorithm is successfully applied to German Traffic Sign Recognition Benchmark (GTSRB) datasets, and the results show that the recognition capabilities of the proposed method are similar to those of other methods. Moreover, its recognition speed is considerably enhanced than related works as approximately 0.47second for 12,630 test data.

An Analysis of the Wintertime Diurnal Wind Variation and Turbulent Characteristics over Yongpyong Alpine Slope (용평 알파인 경기장에서 겨울철 바람의 일변화 및 난류 특성분석)

  • Jeon, Hye-Rim;Kim, Byung-Gon;Eun, Seung-Hee;Lee, Young-Hee;Choi, Byoung-Cheol
    • Atmosphere
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    • v.26 no.3
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    • pp.401-412
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    • 2016
  • A 3D sonic anemometer has been installed at Yongpyong alpine slope since Oct. 23th 2014 to observe the slope winds and to analyze turbulent characteristics with the change in surface cover (grass and snow) and the synoptic wind strength. Eddy covariance method has been applied to calculate the turbulent quantity after coordinate transformation of a planar-fit rotation. We have carefully selected 3 good episodes in the winter season (23 October 2014 to 28 February 2015) for each category (9 days in total), such as grass and snow covers in case of weak synoptic wind condition, and grass cover of strong synoptic wind. The diurnal variations of the slope winds were well developed like the upslope wind in the daytime and downslope wind in the nighttime for both surface covers (grass and snow) in the weak synoptic forcing, when accordingly both heat and momentum fluxes significantly increased in the daytime and decreased in the nighttime. Meanwhile, diurnal variation of heat flux was not present on the snow cover probably in associated with significant fraction of sunlight reflection due to high albedo especially during the daytime in comparison to those on the grass cover. In the strong synoptic regime, the most dominant feature at Yongpyong, only the southeasterly downslope winds were steadily generated irrespective of day and night with significant increases in momentum flux and turbulent kinetic energy as well, which could suggest that local circulations are suppressed by the synoptic scale forcing. In spite of only one season analysis applied to the limited domain, this kind of an observation-based study will provide the basis for understanding of the local wind circulation in the complex mountain domain such as Gangwon in Korea.

A summertime near-ground velocity profile of the Bora wind

  • Lepri, Petra;Kozmar, Hrvoje;Vecenaj, Zeljko;Grisogono, Branko
    • Wind and Structures
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    • v.19 no.5
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    • pp.505-522
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    • 2014
  • While effects of the atmospheric boundary layer flow on engineering infrastructure are more or less known, some local transient winds create difficulties for structures, traffic and human activities. Hence, further research is required to fully elucidate flow characteristics of some of those very unique local winds. In this study, important characteristics of observed vertical velocity profiles along the main wind direction for the gusty Bora wind blowing along the eastern Adriatic coast are presented. Commonly used empirical power-law and the logarithmic-law profiles are compared against unique 3-level high-frequency Bora measurements. The experimental data agree well with the power-law and logarithmic-law approximations. An interesting feature observed is a decrease in the power-law exponent and aerodynamic surface roughness length, and an increase in friction velocity with increasing Bora wind velocity. This indicates an urban-like velocity profile for smaller wind velocities and rural-like velocity profile for larger wind velocities, which is due to a stronger increase in absolute velocity at each of the heights observed as compared to the respective velocity gradient (difference in average velocity among two different heights). The trends observed are similar during both the day and night. The thermal stratification is near neutral due to a strong mechanical mixing. The differences in aerodynamic surface roughness length are negligible for different time averaging periods when using the median. For the friction velocity, the arithmetic mean proved to be independent of the time record length, while for the power-law exponent both the arithmetic mean and the median are not influenced by the time averaging period. Another issue is a large difference in aerodynamic surface roughness length when calculating using the arithmetic mean and the median. This indicates that the more robust median is a more suitable parameter to determine the aerodynamic surface roughness length than the arithmetic mean value. Variations in velocity profiles at the same site during different wind periods are interesting because, in the engineering community, it has been commonly accepted that the aerodynamic characteristics at a particular site remain the same during various wind regimes.

A Study on the Vibration Analysis of a Deckhouse of Fishing Vessel (어선의 갑판실의 진동 해석법에 관한 연구)

  • 배동명
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.27 no.3
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    • pp.193-210
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    • 1991
  • For the deckhouse or superstructure, attention is directed to the reduction of vibration from a human susceptibility point of view. The two basic requirements for obtaining a low vibration level in the accommodation are to ensure that excitation forces from propeller and/or main engine are small and to avoid resonance excitation of the hull and superstructure. In recent years increased attention has been directed towards the problems of vibration and noise in deckhouse, which have caused major problems with regard to the environmental quality in the living quarters for crews. Accordingly, in this paper, the characteristic of the vibration of deckhouse of fishing boat, of which the length/height ratio is also relatively high, are studied systematically with regard to the shape and modelling of deckhouse based on finite element method of 1-dimensional, 2-dimensional and 3-dimensional model. This study is divided into 4-part. 1st part is the global deckhouse vibration, 2nd part is the local deckhouse vibration, 3rd part consists of the estimation for stiffness of foundational support and 4th part is the application to TUNA LONG LINER of 416 ton class. For the global vibration analysis, the severity of the vibration depends on the longitudinal shear and bending stiffness of the deckhouse, on the vertical deckhouse support(fore, aft and sides). However, even if the design is technically sound, vibration problems may arise due to vertical or longitudinal hull girder or afterbody resonances. Author applied the method of this study to the analysis of, deep-sea fishing vessel of G.T. 416 ton class with relatively low height and long deckhouse, and investigated the vibrational characteristic of the fishing vessel with earlier structural feature. According to this investigation, the vibration, response of above vessel was confirmed of which main hull and deckhouse behave as one body. It is at the bottom of vibrational trouble which a accommodation part of the fishing vessel is raised, that is the local vibration for side wall, fore-aft wall and deck plate of deckhouse rather than thief fect of fore-aft vibration of deckhouse for above fishing vessel. and the resonance of main hull, deckhouse and driving system such as the main engine, propeller in exciting source is mainly brought up as the trouble.

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Research on international examples on prevention of juvenile delinquency

  • Park, Jong-Ryeol;Noe, Sang-Ouk
    • Journal of the Korea Society of Computer and Information
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    • v.25 no.8
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    • pp.151-157
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    • 2020
  • The first thing we can consider to prevent juvenile delinquency is to punish those criminals. However, this is not always the proper solution. In consideration to the feature of juvenile period when they lack in proper judgment it is better to provide education than punishment so that they are not branded as criminals in our society. Also, by returning to the society, they can obtain social techniques and obtain the opportunity of making contribution to the society, which is also good for their career development. Combining international examples on juvenile delinquency prevention, there is a need to comprehensively evaluate level of probation and risk exposure of juvenile based on placement matrix of comprehensive strategy program in the US. Also, control solution by juvenile crime development phase should be made. In terms of control treatment based on crime phase, crime history should be considered when applying control. For the subject of preventing juvenile crime, it shouldn't be legal organizations like before but shall be home, school, local society, and legal organization together.

ECG signal compression based on B-spline approximation (B-spline 근사화 기반의 심전도 신호 압축)

  • Ryu, Chun-Ha;Kim, Tae-Hun;Lee, Byung-Gook;Choi, Byung-Jae;Park, Kil-Houm
    • Journal of the Korean Institute of Intelligent Systems
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    • v.21 no.5
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    • pp.653-659
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    • 2011
  • In general, electrocardiogram(ECG) signals are sampled with a frequency over 200Hz and stored for a long time. It is required to compress data efficiently for storing and transmitting them. In this paper, a method for compression of ECG data is proposed, using by Non Uniform B-spline approximation, which has been widely used to approximation theory of applied mathematics and geometric modeling. ECG signals are compressed and reconstructed using B-spline basis function which curve has local controllability and control a shape and curve in part. The proposed method selected additional knot with each step for minimizing reconstruction error and reduced time complexity. It is established that the proposed method using B-spline approximation has good compression ratio and reconstruct besides preserving all feature point of ECG signals, through the experimental results from MIT-BIH Arrhythmia database.

Image Feature based Inpainting Scheme for Restoration of Line Scratch of Old Film (오래된 영화의 line scratch 복원을 위한 영상특성추출기반의 인페인팅)

  • Ko, Ki-Hong;Kim, Seong-Whan
    • The KIPS Transactions:PartD
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    • v.15D no.4
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    • pp.581-588
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    • 2008
  • Old films or photographs usually have damages from physical or chemical effects, and the damage and digitalization make stain, scratch, scribbling, noise, and digital drop out in frames. Damages include global damage and local damage, and it is well known that local damage restoration is a main factor for improving image quality. Previous researches have focused on impairment localization (esp. for line scratch impairments) and restoration techniques for line scratch, dirt, blob, and intentional scratch. Inpainting is a key technique using partial derivatives to restore damages in images. It does not show good quality for the complex images because it is based on finite order for partial derivatives, and it takes much time complexity. In this paper, we present a modified inpainting scheme, where we use Sobel edge operator's and angle to compute isophotes, and compare our scheme with Bertalmio's scheme. We experiment our scheme with two old Korean films, and Simulation results show that our scheme requires smaller time complexity than Bertalmio's scheme with comparable reconstructed image quality.

Object Tracking Using Particle Filters in Moving Camera (움직임 카메라 환경에서 파티클 필터를 이용한 객체 추적)

  • Ko, Byoung-Chul;Nam, Jae-Yeal;Kwak, Joon-Young
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37 no.5A
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    • pp.375-387
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    • 2012
  • This paper proposes a new real-time object tracking algorithm using particle filters with color and texture features in moving CCD camera images. If the user selects an initial object, this region is declared as a target particle and an initial state is modeled. Then, N particles are generated based on random distribution and CS-LBP (Centre Symmetric Local Binary Patterns) for texture model and weighted color distribution is modeled from each particle. For observation likelihoods estimation, Bhattacharyya distance between particles and their feature models are calculated and this observation likelihoods are used for weights of individual particles. After weights estimation, a new particle which has the maximum weight is selected and new particles are re-sampled using the maximum particle. For performance comparison, we tested a few combinations of features and particle filters. The proposed algorithm showed best object tracking performance when we used color and texture model simultaneously for likelihood estimation.

A Study on the Structural Characteristics and Metal Ornament of Jeonju-Jang (전주장의 구조적 특징과 금구장식 연구)

  • Baik, Da hee;Lim, Seung Taek
    • Journal of the Korea Furniture Society
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    • v.28 no.3
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    • pp.207-223
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    • 2017
  • Jeonju-Jang is the wood furniture that was made in Chonbuk Jeonju province during the Joseon Dynasty, and was used by middle-upper social classes. It has value as a local cultural heritage because it has unique characteristics in terms of the shape of the furniture, the metal ornament and various functions are integrated in accordance with user's requirements. Therefore, the purpose of this study is to define the structural characteristics of the Jeonju-Jang through case studies of 16 existing artifacts in order to preserve and inherit the value as local cultural resources. The conclusion is as follows. First, Jeonju-Jang in the late period of Joseon Dynasty that is made up of one board to the bottom with the binding of the board. and the front wall, the Juibyuckkan and the Meoruemkan are omitted or made small, so the structure of the surface is simple. There are three or four drawers under the Cheon pan(top plate). There are drawers and shelf inside the hinged door. In the case of a two-layer type, there is a Gaegumeong type door which has half of one side hinged. Second, Jeonju-Jang of the Japanese Ruling Era had a Juibyuckkan by frame binding and an increase in the number of Meoruemkan. and it had independent legs. The Cheon-pan(top plate) was more left and right than both sides. Third, in the late Joseon Dynasty period as a feature of the metal ornaments, cast iron and yellow brass were used as materials. In the Japanese Ruling Era, nickel was mainly used. Various patterns were engraved and the number increased, and it became gorgeous surface as a whole.

Reconstruction of Post Burn Ala Defect Using Adiposocutaneous Graft (지방피부복합조직 이식을 이용한 화상 후 콧방울 결손의 재건)

  • Kwon, Min-Joo;Lee, Jong-Wook;Koh, Jang-Hyu;Seo, Dong-Kook;Choi, Jai-Ku;Jang, Young-Chul
    • Archives of Plastic Surgery
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    • v.38 no.4
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    • pp.451-457
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    • 2011
  • Purpose: As a central feature of the face, the nose has considerable significance in appearance and expression. Reconstruction of full thickness defects of the nasal ala has always been a challenge because of the 3-dimensional structure. For reconstruction of post burn defects of ala, skin graft, local or pedicled flap and composite graft are optionally available. We have reconstructed the ala defects using adiposocutaneous graft and observed the outcome. Methods: From March 2003 to December 2010, 19 cases in 11 patients with scar contracture and defect on ala portion were performed operation using adiposocutaneous graft. As a donor site, we used the inguinal crease and posterior auricular area and the donor site was primarily closed. We made incision through the superior rim of ala and released fully. A graft is applied to recipient site with larger size than recipient volume. Results: The mean age of the patient was 38.6 years (16~51), males are seven patients and females are four patients. The operation was performed bilaterally in 5 patients and unilaterally in 6 patients. Composite grafts were harvested from inguinal area in 13 cases and posterior auricular area in 6 cases. In one case, we did 4 times of operation to get enough volume. All the grafts were well taken. The mean size of the graft was 3.63 $cm^2$. Conclusion: For reconstruction of post burn defects of ala, it's not easy to use local flap or pedicled flap because of hardness and fibrosis of surrounding tissue. So, we choose adiposocutaneous graft for ala deformity reconstruction, got satisfactory outcome in color matching and texture.