• Title/Summary/Keyword: Spatial Transformation

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Image Registration in Medical Applications

  • Hong, Helen
    • Journal of International Society for Simulation Surgery
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    • v.1 no.2
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    • pp.62-66
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    • 2014
  • Image registration is the process for finding the correct geometrical transformation that brings one image in precise spatial correspondence with another image. There are limitations on the visualization of simple overlay between two different modality images because two different modality images have different anatomical information, resolution, and viewpoint. In this paper, various image registration methods and their applications are introduced. With the recent advance of medical imaging device, image registration is used actively in diagnosis support, treatment planning, surgery guidance and monitoring the disease progression.

Comparative study on dynamic analyses of non-classically damped linear systems

  • Greco, Annalisa;Santini, Adolfo
    • Structural Engineering and Mechanics
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    • v.14 no.6
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    • pp.679-698
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    • 2002
  • In this paper some techniques for the dynamic analysis of non-classically damped linear systems are reviewed and compared. All these methods are based on a transformation of the governing equations using a basis of complex or real vectors. Complex and real vector bases are presented and compared. The complex vector basis is represented by the eigenvectors of the complex eigenproblem obtained considering the non-classical damping matrix of the system. The real vector basis is a set of Ritz vectors derived either as the undamped normal modes of vibration of the system, or by the load dependent vector algorithm (Lanczos vectors). In this latter case the vector basis includes the static correction concept. The rate of convergence of these bases, with reference to a parametric structural system subjected to a fixed spatial distribution of forces, is evaluated. To this aim two error norms are considered, the first based on the spatial distribution of the load and the second on the shear force at the base due to impulsive loading. It is shown that both error norms point out that the rate of convergence is strongly influenced by the spatial distribution of the applied forces.

A Study on the Interpretation of Modern Urban Structure and Urban Landscape of Iri(Iksan) in Connection with Railway (철도시설과 연계한 이리 도시구조와 도시경관의 근대성 해석)

  • Lee, Kyung-Chan
    • Journal of architectural history
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    • v.21 no.6
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    • pp.63-76
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    • 2012
  • Modern railway construction by Japanese had a great influence on the urbanization, transformation of urban structure and landscape during the Japanese imperialism and compressive increasing period in Iri(Iksan). This paper aims to find out the effect of railway on the modern urban structure and urban landscape in Iri(Iksan). Railways in Iri, Honam railway, Kunsan railway, Jeonla railway have been constructed progressively during 1911 and 1915 with Iri and old Iri(east-Iri) station. From the analysis of land registration maps and street plans, old photographies and historical records, some significant features underling railway construction can be followed in view of modern urbanization process in Iri. Firstly railways cut off the possibility of developing urban structure based on traditional spatial structure of Iksan. Secondly railways made dual spatial structure in Iri. Japanese and Korean life zone were divided into separate district around urbanization area and market place. Thirdly traditional space cognition system based on four cardinal directions were changed to front and rear space of railway station. Fourthly railways and stations caused neo-baroque spatial order and imperialistic urban landscape of Iri with axis, vista and gridiron plan. Fifthly break points and fringe belts garbling modern urbanization process are created. Sixthly modern cultural and consumptive urban spaces were taken their seats in relation with daily urban life.

Application of Video Photogrammetry for Generating and Updating Digital Maps (수치지도 생성 및 갱신을 위한 Video Photogrammetry 적용)

  • Yoo, Hwan-Hee;Sung, Jae-Ryeol
    • Journal of Korean Society for Geospatial Information Science
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    • v.6 no.2 s.12
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    • pp.11-20
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    • 1998
  • Although aerial photogrammetry has been used to generate or update digital maps. It is difficult to make the spatial and attribute data for all kinds of objects on the ground with only aerial photogrammetry. Therefore, we are getting informations of the object on the ground through an on-the-spot survey In order to improve accuracy and reliability of on-the-spot survey in this study, we obtained stereo images from high resolution digital camera (1152*864 pixels) and developed the video photogrammetry which was able to determine the three dimensional coordinates from stereo images by applying DLT(Direct Linear Transformation). Also, the developed video photogrammetry could generate and update the spatial and attribute data in digital maps by using a function that could connect three dimensional coordinates with the attribute data.

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Cattle Do Remember Locations of Preferred Food over Extended Periods

  • Ksiksi, T.;Laca, E.A.
    • Asian-Australasian Journal of Animal Sciences
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    • v.15 no.6
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    • pp.900-904
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    • 2002
  • The duration of spatial memory in cattle is potentially important for grazing management. The ability of livestock to remember the location of food patches may lead to uneven range use. In this experiment, how long cattle are able to remember food locations was determined. Six steers were used to conduct this study in a pasture with an 8 row by 8 column grid of 64 plastic containers 5 meters apart. Four randomly chosen containers were loaded with feed pellets. All steers were trained to find the loaded locations until a minimum of empty containers were visited. After this initial training, each steer was tested at 5, 10, 20 and 48 days post-training. Total number of visits (TV), number of containers visited (NC), the ratio of loaded containers (LC) to NC were recorded. Once the steers learned the locations of loaded containers NC did not increase with time since last training up to 48 days (p>0.05). Logarithmic transformation of NC (LNC) was 0.70 and 0.80 for the control and 48 day treatments, respectively. Steers were equally efficient in locating containers with feed. The steers also showed that their ability in locating food was much better than expected by chance (Z>1.62). Findings of the present study do not suggest using spatial memory decay as a tool to promote better grazing distribution. Because steers remembered food locations accurately for at least 48 days.

Capturing the Underlying Structure of a 'Segment-line' City: Its Configurational Evolution and Functional Implications

  • Ling, Michelle Xiaohong
    • International Journal of High-Rise Buildings
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    • v.6 no.2
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    • pp.139-147
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    • 2017
  • Analyzing morphological evolution over a long period of time is deemed an effective way to identify problems occurring in the process of urban development, in addition to achieving a fundamental understanding of socio-cultural changes and growth rooted from the context. As far as the urban morphology is concerned, Hong Kong is characterized by its unique high-density and compact layout patterns, which have aroused the interest of a number of authors in the urban design domain. Whilst an increasing number of redevelopment projects in Hong Kong were criticized for ignoring and destroying the old urban fabric, there is a need for research to investigate the origins and changes of various urban patterns and their implications for society. By employing the theories and techniques of space syntax, this paper accordingly provides a morphological analysis based on the Wanchai District - a 'Segment-line' city, which particularly epitomizes various urban grids of Hong Kong and may have different implications for functional aspects. By axial-mapping the urban layouts of five stages of growth since 1842 and subsequently investigating their spatial and functional transformation over the past 170 years, this paper identifies a series of spatial characteristics underlying different grid patterns, as well as achieves a precise understanding of their ever changing relationship. Based on these understandings, this paper intends to provide valuable reference and guidance for upcoming spatial development in Hong Kong and other regions.

Design of a foot shape extraction system for foot parameter measurement (발 고유 변인 측정을 위한 발 형상 추출 시스템 설계)

  • Yun, Jeongrok;Kim, Hoemin;Kim, Unyong;Chun, Sungkuk
    • Proceedings of the Korean Society of Computer Information Conference
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    • 2020.07a
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    • pp.421-422
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    • 2020
  • 발 고유 변인 측정 및 데이터의 수집은 소비자의 발 건강을 위한 신발 제작을 위하여 필요하다. 신발의 설계 지표 또한 개정의 필요성이 제시되고 있어 발 고유 변인 측정의 및 데이터 획득에 관한 연구의 필요성이 증대되고 있다. 본 논문에서는 발 형태의 데이터 값을 산출하여 사용자에게 적합한 맞춤형 인솔 및 신발을 제작하고, 신발의 설계 지표를 산출하기 위하여 발 고유 변인의 데이터 값을 자동으로 측정이 가능한 발 고유 변인 산출이 가능한 발 형상 추출 시스템에 대해 서술한다. 이를 위해 사용자의 발 고유 변인 측정을위한 스캐닝 스테이지를 설계 및 제작하고, 3대의 깊이 카메라를 설치하였다. 잡음 및 배경을 제거하기 위해 가우시안 배경 모델링으로 전경 영역을 분리하여 발 점군 데이터를 획득 한 후, Euclidean transformation을 통해 각 점군 데이터를 정합한다. 실험 결과에서는 획득된 발 형상 점군 데이터와 접지면 형상 및 발 변인 추출 결과를 보여준다.

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Geocoding of Low Altitude UAV Imagery using Affine Transformation Model (부등각사상변환을 이용한 저고도 UAV 영상의 지형보정)

  • Kim, Seong-Sam;Jung, Jae-Hoon;Kim, Eui-Myoung;Yoo, Hwan-Hee;Sohn, Hong-Gyoo
    • Journal of Korean Society for Geospatial Information Science
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    • v.16 no.4
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    • pp.79-87
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    • 2008
  • There has been a strong demand for low altitude UAV development in rapid mapping not only to acquire high resolution image with much more low cost and weather independent, compared to satellite surveying or traditional aerial surveying, but also to meet many needs of the aerial photogrammetry. Especially, efficient geocoding of UAV imagery is the key issue. Contrary to high UAV potential for civilian applications, the technology development in photogrammetry for example direct georeferencing is in the early stage and it requires further research and additional technical development. In this study, two approaches are supposed for automatic geocoding of UAV still images by simple affine transformation and block adjustment of affine transformation using minimal ground control points and also evaluated the applicability and quality of geometric model compared to geocoded images generated by commercial S/W.

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Deep Learning: High-quality Imaging through Multicore Fiber

  • Wu, Liqing;Zhao, Jun;Zhang, Minghai;Zhang, Yanzhu;Wang, Xiaoyan;Chen, Ziyang;Pu, Jixiong
    • Current Optics and Photonics
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    • v.4 no.4
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    • pp.286-292
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    • 2020
  • Imaging through multicore fiber (MCF) is of great significance in the biomedical domain. Although several techniques have been developed to image an object from a signal passing through MCF, these methods are strongly dependent on the surroundings, such as vibration and the temperature fluctuation of the fiber's environment. In this paper, we apply a new, strong technique called deep learning to reconstruct the phase image through a MCF in which each core is multimode. To evaluate the network, we employ the binary cross-entropy as the loss function of a convolutional neural network (CNN) with improved U-net structure. The high-quality reconstruction of input objects upon spatial light modulation (SLM) can be realized from the speckle patterns of intensity that contain the information about the objects. Moreover, we study the effect of MCF length on image recovery. It is shown that the shorter the fiber, the better the imaging quality. Based on our findings, MCF may have applications in fields such as endoscopic imaging and optical communication.

Research on Digital Twin Automation Techniques in the Construction Industry through 2D Design Drawing Data Extraction and 3D Spatial Data Construction (2D 설계도면 데이터 추출 및 3차원 공간 데이터 구축을 통한 건설산업 디지털 트윈 자동화 기법 연구)

  • Lee, Jongseo;Moon, Il-YOUNG
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2021.10a
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    • pp.609-612
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    • 2021
  • Government agencies and companies are establishing and promoting digital transformation strategies in various industrial fields, and are leading the era of the 4th industrial revolution through successful technological innovation. In this time of change, we can see many stories of global companies Nike and Starbucks as successful examples of digital transformation. These two companies are showing successful results through digital transformation. Domestic companies are also conducting digital innovation based on mobile, cloud, IoT, artificial intelligence, and AR/VR technologies, and are establishing RPA (Robotic Process Automation) processes for high efficiency and high productivity. In this paper, we introduce the 3D digital twin space construction automation process technique using data from the entire construction cycle of design, construction, and maintenance of the construction industry, and look into the digital transformation strategy of the construction industry in the future.

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