• Title/Summary/Keyword: Coordinate system

Search Result 2,222, Processing Time 0.044 seconds

A Study on Stroke Extraction for Handwritten Korean Character Recognition (필기체 한글 문자 인식을 위한 획 추출에 관한 연구)

  • Choi, Young-Kyoo;Rhee, Sang-Burm
    • The KIPS Transactions:PartB
    • /
    • v.9B no.3
    • /
    • pp.375-382
    • /
    • 2002
  • Handwritten character recognition is classified into on-line handwritten character recognition and off-line handwritten character recognition. On-line handwritten character recognition has made a remarkable outcome compared to off-line hacdwritten character recognition. This method can acquire the dynamic written information such as the writing order and the position of a stroke by means of pen-based electronic input device such as a tablet board. On the contrary, Any dynamic information can not be acquired in off-line handwritten character recognition since there are extreme overlapping between consonants and vowels, and heavily noisy images between strokes, which change the recognition performance with the result of the preprocessing. This paper proposes a method that effectively extracts the stroke including dynamic information of characters for off-line Korean handwritten character recognition. First of all, this method makes improvement and binarization of input handwritten character image as preprocessing procedure using watershed algorithm. The next procedure is extraction of skeleton by using the transformed Lu and Wang's thinning: algorithm, and segment pixel array is extracted by abstracting the feature point of the characters. Then, the vectorization is executed with a maximum permission error method. In the case that a few strokes are bound in a segment, a segment pixel array is divided with two or more segment vectors. In order to reconstruct the extracted segment vector with a complete stroke, the directional component of the vector is mortified by using right-hand writing coordinate system. With combination of segment vectors which are adjacent and can be combined, the reconstruction of complete stroke is made out which is suitable for character recognition. As experimentation, it is verified that the proposed method is suitable for handwritten Korean character recognition.

Position Based Triangulation for High Performance Particle Based Fluid Simulation (위치 기반 삼각화를 이용한 입자 기반 유체 시뮬레이션 가속화 기법)

  • Hong, Manki;Im, Jaeho;Kim, Chang-Hun;Byun, Hae Won
    • Journal of the Korea Computer Graphics Society
    • /
    • v.23 no.1
    • /
    • pp.25-32
    • /
    • 2017
  • This paper proposes a novel acceleration method for particle based large scale fluid simulation. Traditional particle-based fluid simulation has been implemented by interacting with physical quantities of neighbor particles through the Smoothed Particle Hydrodynamics(SPH) technique[1]. SPH method has the characteristic that there is no visible change compared to the computation amount in a part where the particle movement is small, such as a calm surface or inter-fluid. This becomes more prominent as the number of particles increases. Previous work has attempted to reduce the amount of spare computation by adaptively dividing each part of the fluid. In this paper, we propose a technique to calculate the motion of the entire particles by using the physical quantities of the near sampled particles by sampling the particles inside the fluid at regular intervals and using them as reference points of the fluid motion. We propose a technique to adaptively generate a triangle map based on the position of the sampled particles in order to efficiently search for nearby particles, and we have been able to interpolate the physical quantities of particles using the barycentric coordinate system. The proposed acceleration technique does not perform any additional correction for two classes of fluid particles. Our technique shows a large improvement in speed as the number of particles increases. The proposed technique also does not interfere with the fine movement of the fluid surface particles.

Analyses on the Impact of Plastic Deformation on Change of the Road Surface Condition (소성변형 정도를 고려한 시간전개에 따른 노면상태 변화 분석)

  • SON, Young Tae;PARK, Sang-Hyun
    • Journal of Korean Society of Transportation
    • /
    • v.36 no.3
    • /
    • pp.216-228
    • /
    • 2018
  • In this study analyzed the ponding changing of plastic deformation section follwed time development to apply weather, geometry and traffic data in additon to time development to improve road management service and safety of roads during or after rain. After We selected an 8.3km section of old national highway the Seongnam-Janghowon section and created a three-demensional surface of terrain through the numerical transformantion of design drawing data, with reflection the linear data of the same coordinate system in order to describe more realistic roads, we design additional structures with shading above roads. The altitude and azimuth of the sun were calculated and set based on the longitude and latitude data of the survey line for the analysis of the sun rate, and the daylight impact zone was visualized by setting the shaded time to an interval of 1 hour and the shade rate of the corresponding section. In addition, the evaporation volume calculated from weather data such as temperature, humidity, radiant energy, and road temperature analyzes together, it will use the way of a safer and more efficient road management as grasping the ponding changing more efficent in time development.

Static and Dynamic Analysis of Reinforced Concrete Axisymmetric Shell on the Elastic Foundation -Effect of Steel on the Dynamic Response- (탄성지반상에 놓인 철근 콘크리트 축대칭 쉘의 정적 및 동적 해석(IV) -축대칭 쉘의 동적 응답에 대한 철근의 영향을 중심으로-)

  • 조진구
    • Magazine of the Korean Society of Agricultural Engineers
    • /
    • v.39 no.4
    • /
    • pp.106-113
    • /
    • 1997
  • Dynamic loading of structures often causes excursions of stresses well into the inelastic range, and the influence of the geometric changes on the dynamic response is also significant in many cases. Therefore, both material and geometric nonlinearity effects should be considered in case that a dynamic load acts on the structure. A structure in a nuclear power plant is a structure of importance which puts emphasis on safety. A nuclear container is a pressure vessel subject to internal pressure and this structure is constructed by a reinforced concrete or a pre-stressed concrete. In this study, the material nonlinearity effect on the dynamic response is formulated by the elasto-viscoplastic model highly corresponding to the real behavior of the material. Also, the geometrically nonlinear behavior is taken into account using a total Lagrangian coordinate system, and the equilibrium equation of motion is numerically solved by a central difference scheme. The constitutive relation of concrete is modeled according to a Drucker-Prager yield criterion in compression. The reinforcing bars are modeled by a smeared layer at the location of reinforcements, and the steel layer model under Von Mises yield criteria is adopted to represent an elastic-plastic behavior. To investigate the dynamic response of a nuclear reinforced concrete containment structure, the steel-ratios of 0, 3, 5 and 10 percent, are considered. The results obtained from the analysis of an example were summarized as follows 1. As the steel-ratio increases, the amplitude and the period of the vertical displacements in apex of dome decreased. The Dynamic Magnification Factor(DMF) was some larger than that of the structure without steel. However, the regular trend was not found in the values of DMF. 2. The dynamic response of the vertical displacement and the radial displacement in the dome-wall junction were shown that the period of displacement in initial step decreased with the steel-ratio increases. Especially, the effect of the steel on the dynamic response of radial displacement disapeared almost. The values of DMF were 1.94, 2.5, 2.62 and 2.66, and the values increased with the steel-ratio. 3. The characteristics of the dynamic response of radial displacement in the mid-wall were similar to that of dome-wall junction. The values of DMF were 1.91, 2.11, 2.13 and 2.18, and the values increased with the steel-ratio. 4. The amplitude and the period of the hoop-stresses in the dome, the dome-wall junction, and the mid-wall were shown the decreased trend with the steel-ratio. The values of DMF were some larger than those of the structure without steel. However, the regular trend was not found in the values of DMF.

  • PDF

Comparison of analysis methods of estimating behavior of soil mass above rigid culvert (암거 상부지반의 거동 평가를 위한 해석법 비교)

  • Lee, Seung-Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.19 no.8
    • /
    • pp.71-77
    • /
    • 2018
  • In order to estimate behavior of soil mass which is located straight up of reinforced concrete culvert, Ritz method and FEM were applied and arching effects between the soil mass and adjacent soil were considered for the analyses. Analysis results obtained from the Ritz method and finite element method were compared with analytical solution. In the case of estimating nodal forces considered in FEM, caution is needed that shear stress depending on depth from ground surface should be reflected regardless of local coordinate system. Comparing the displacements computed from Ritz method with those of the analytic solution, it is seen that as the power of assumed displacement function increases, differences between the computed displacements and those of analytic solution decreases. It seems that displacements of FEM becomes closer to those of analytical solution as the number of elements are increased. It is seen that stresses computed from the Ritz method don't get closer to those of the analytic solution as the power of assumed displacement function. Stresses from FEM become closer to those of analytic solution as the number of elements are increased. Comparing the analysis results from the Ritz method and FEM with those of analytic solution, it can be seen that FEM is more reliable than Ritz method.

Indicators and Planning Features of Ecologically Based Urban Regeneration -Cases from Hamburg, Germany and Copenhagen, Denmark (생태기반형 도시재생의 계획지표 및 특성에 관한 연구 -독일 함부르크와 덴마크 코펜하겐 사례를 중심으로)

  • Rhee, Bum-Hun;Chang, Dong-Min
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.19 no.10
    • /
    • pp.158-166
    • /
    • 2018
  • Contrary to urban development, urban regeneration is a process of land development through conservation, restoration, and management. In particular, ecologically based urban regeneration is an attempt to improve the quality of life in an area, establish a stable settlement space, and revitalize the local economy by considering the ecological environment. In this regard, the objectives of this study were to establish theoretical concepts and analyze the successful foreign cases of ecologically based urban regeneration, and propose a direction of socio-economic regeneration along with the physical-environmental regeneration of urban areas in Korea. The study results suggest the following. First, strategies must be developed to coordinate public transportation, such as buses and subways, by considering the importance of bicycle riders, along with the sustainable-commuting system. Second, both the importance of planning parks and trails around water systems in various scales while maintaining the existing natural environment as well as using natural elements, such as electric vehicles and wind-power generation systems, were emphasized. Third, urban regeneration for increased energy efficiency requires specific architectural planning and facilities. Fourth, education and research for easy access by the public, as well as public-private partnership, will be needed in the regeneration process.

Ocean Circulation Model ing of East Sea for Aquatic Dispersion of Liquid Radioactive Effluents from Nuclear Power Plants (원전 액체 방사성 유출물 해양확산 평가를 위한 동해 해수순환 모델링)

  • Chung Yang-Geun;Lee Gab-Bock;Bang Sun-Young;Lee Ung-Gwon;Lee Yong-Sun
    • Proceedings of the Korean Radioactive Waste Society Conference
    • /
    • 2005.11a
    • /
    • pp.321-331
    • /
    • 2005
  • Recently. three-dimensional models have been used for aquatic dispersion of radioactive effluents in relation to nuclear power plant siting based on the Notice No. 2003-12 'Guideline for investigating and assessing hydrological and aquatic characteristics of nuclear facility site' of the Ministry of Science and Technology (MOST) in Korea. Several nuclear power plants have been under construction or planed. which are Shin-Korl Unit 1 and 2, Shin-Wolsong Unit 1 and 2, and Shln-Ulchin Unit 1 and 2. For assessing the aquatic dispersion of radionuclides released from the above nuclear power plants, it is necessary to know the coastal currents around sites which are affected by circulation of East Sea. In this study, a three dimensional hydrodynamic model for the circulation of the East Sea of Korea has been developed as the first Phase, which Is based on the RIAMOM. The model uses the primitive equation with hydrostatic approximation, and uses Arakawa-B grid system horizontally and Z-coordinate vertically. Model domain is $126.5^{\circ}E\;to\;142.5^{\circ}E$ of east longitude and $33^{\circ}N\;and\;52^{\circ}N$ of the north latitude. The space of the horizontal grid was $1/12^{\circ}$ to longitude and latitude direction and vortical level was divided to 20. This model uses Generalized Arakawa Scheme. Slant Advection, and Mode-Splitting Method. The input data were from JODC, KNFRDI, and ECMWF. The model ing results are in fairly good agreement with schematic patterns of the surface circulation in the East Sea The local current model and aquatic dispersion model of the coastal region will be developed as the second phase. The oceanic dispersion experiments will be also tarried out by using ARGO Drifter around a nuclear pelter plant site.

  • PDF

Identifying the Usefulness of Weblog Genre Analysis in Organizational knowledge Creation: A Social Construction of Technology Perspective (조직내 지식창출을 위한 웹블로그 장르분석의 유용성 발굴: 기술의 사회구성론적 관점)

  • Park, Ji-Hong
    • Journal of the Korean Society for information Management
    • /
    • v.25 no.1
    • /
    • pp.5-17
    • /
    • 2008
  • The purpose of this paper is to identify the usefulness of Weblog genre analysis in knowledge creation within an organization where communications are occurred frequently among the employees with information and communication technologies (ICTs). Knowledge creation is essential to achieve competitive advantage in today's knowledge-oriented working environments. There has been huge investment on knowledge management systems to achieve such advantages. It is, however, widely recognized that distributed knowledge management systems often fail due to the different social contexts across the sub-organizations where the local information systems are deployed. It is important to coordinate such social gaps across the sub-organizations to achieve better advantages. Given that Weblogs users often feel a shared social norm. Weblogs playa positive role of narrowing the social gaps. This paper argues that the genre analysis of Web logs could provide important clues to narrow the social gaps existed across the sub-organizations within an organization. Hence, such taxonomical practice may be a solution for the high rate of failure in knowledge management system implementations in an organization. This paper uses the theory of organizational knowledge creation (Nonaka & Takeuchi. 1995) and social construction of technology (SCOT) approach (Bijker, 1995) to compare the socialized with the non-socialized integration of distributed information systems. The findings of this research provide a useful framework for better implementing knowledge management practices especially in distributed working environments.

Log-Polar Image Watermarking based on Invariant Centroid as Template (불변의 무게중심을 템플릿으로 이용한 대수-극 좌표계 영상 워터마킹 기법)

  • 김범수;유광훈;김우섭;곽동민;송영철;최재각;박길흠
    • Journal of KIISE:Computing Practices and Letters
    • /
    • v.9 no.3
    • /
    • pp.341-351
    • /
    • 2003
  • Digital image watermarking is the method that can protect the copyright of the image by embedding copyright information, which is called watermark. Watermarking must have robustness to intentional or unintentional data changing, called attack. The conventional watermarking schemes are robust to waveform attacks such as image compression, filtering etc. However, they are vulnerable to geometrical attacks such as rotation, scaling, translation, and cropping. Accordingly, this paper proposes new watermarking scheme that is robust to geometrical attacks by using invariant centroid. Invariant centroid is the gravity center of a central area in a gray scale image that remains unchanged even when the image is attacked by RST including cropping and proposed scheme uses invariant centroids of original and inverted image as the template. To make geometrically invariant domain, template and angle compensated Log -Polar Map(LPM) is used. Then Discrete Cosine Transform(DCT) is performed and the watermark is embedded into the DCT coefficients. Futhermore, to prevent a watermarked image from degrading due to interpolation during coordinate system conversion, only the image of the watermark signal is extracted and added to the original image. Experimental results show that the proposed scheme is especially robust to RST attacks including cropping.

Analysis and Evaluation of Integration Policy of Local Government in 2010~2014 : Focused on Multi-Dimensional Model (2010~2014년 시·군·구 통합정책의 분석과 평가: 다차원분석모형을 중심으로)

  • Kim, Cheol Hoi;Jin, Jae-Wan
    • The Journal of the Korea Contents Association
    • /
    • v.15 no.1
    • /
    • pp.123-131
    • /
    • 2015
  • The purpose of this study was to find out the reason why the integration policy of local government in 2010~2014 has failed in the light of multi-dimensional model including normative, structural, constituentive, and technical dimension. Central government pushed integration policy of local government focused on increasing economic efficiency based on the theory of economy of scale on 16 regions and 36 local governments. Only one region(Cheong-Ju and Cheong-Won), however, completed integration procedure in 2014. Although most regions don't have common value on integration, and cultural, political ties in normative and structural dimension, central government pushed the integration policy. Futhermore central government failed to coordinate various interests of the participants and design incentive system including demands of local residents in constituentive and technical dimension. Based on this study central government should consider these policy implications when it propel the integration policy of local government in the future.