• Title/Summary/Keyword: Primitive mapping

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Ship Outfitting Design Data Exchange between CAD Systems Using Different Primitive Set (서로 다른 프리미티브 집합을 사용하는 CAD 시스템 사이에 선박 의장 설계 데이터의 교환)

  • Lee, Seunghoon;Han, Soonhung
    • Korean Journal of Computational Design and Engineering
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    • v.18 no.3
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    • pp.234-242
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    • 2013
  • Different CAD systems are used in ship outfitting design on different usage and purpose. Therefore, data exchanges between CAD systems are required from different formats. For data exchange, boundary representation standard formats such as IGES and ISO 10303 (STEP) are widely used. However, they present only B-rep representation. Because of different CAD systems have their own geometry format, data exchanges with design intend are difficult. Especially, Tribon and PDMS use primitives for express their geometry in ship outfitting design. However, Tribon primitives are represented their parameter by values that are non-parametric. Therefore, data size of catalogue library is bigger than different CAD system using parametric primitive representation. And that system has difficulty on data reprocessing. To solve that problem, we discuss about shape DB which contains design parameters of primitive for exchange Tribon primitives. And geometry data exchange between Tribon and Shape Database that defines based on PDMS scheme are specified using primitive mapping that can represent design intend.

Semantic Mapping of Terms Based on Their Ontological Definitions and Similarities (온톨로지 기반의 용어 정의 비교 및 유사도를 고려한 의미 매핑)

  • Jung W.C.;Lee J.H.;Suh H.W.
    • Korean Journal of Computational Design and Engineering
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    • v.11 no.3
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    • pp.211-222
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    • 2006
  • In collaborative environment, it is necessary that the participants in collaboration should share the same understanding about the semantics of terms. For example, they should know that 'COMPONENT' and 'ITEM' are different word-expressions for the same meaning. In order to handle such problems in information sharing, an information system needs to automatically recognize that the terms have the same semantics. So we develop an algorithm mapping two terms based on their ontological definitions and their similarities. The proposed algorithm consists of four steps: the character matching, the inferencing, the definition comparing and the similarity checking. In the similarity checking step, we consider relation similarity and hierarchical similarity. The algorithm is very primitive, but it shows the possibility of semi-automatic mapping using ontology. In addition, we design a mapping procedure for a mapping system, called SOM (semantic ontology mapper).

Geometry-to-BIM Mapping Rule Definition for Building Plane BIM object (건축물 평면 형상에 대한 형상-to-BIM 맵핑 규칙 정의)

  • Kang, Tae-Wook
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.10
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    • pp.236-242
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    • 2019
  • Recently, scanning projects have been carried out in various construction and construction fields for maintenance purposes. The point cloud generated by the scan results is composed of a number of points representing the object to be scanned. The process of extracting the necessary information, including dimensions, from such scan data is called paradox. The reverse engineering process of modeling a point cloud as BIM involves considerable manual work. Owing to the time-consuming reverse engineering nature of the work, the costs increase exponentially when rework requests are made, such as design changes. Reverse engineering automation technology can help improve these problems. On the other hand, the reverse design product is variable depending on the use, and the kind and detail level of the product may be different. This paper proposes the G2BM (Geometry-to-BIM mapping) rule definition method that automatically maps a BIM object from a primitive geometry to a BIM object. G2BM proposes a process definition and a customization method for reverse engineering BIM objects that consider the use case variability.

Reconstruction of a 3D Model using the Midpoints of Line Segments in a Single Image (한 장의 영상으로부터 선분의 중점 정보를 이용한 3차원 모델의 재구성)

  • Park Young Sup;Ryoo Seung Taek;Cho Sung Dong;Yoon Kyung Hyun
    • Journal of KIISE:Computer Systems and Theory
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    • v.32 no.4
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    • pp.168-176
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    • 2005
  • We propose a method for 3-dimensionally reconstructing an object using a line that includes the midpoint information from a single image. A pre-defined polygon is used as the primitive and the recovery is processed from a single image. The 3D reconstruction is processed by mapping the correspondence point of the primitive model onto the photo. In the recent work, the reconstructions of camera parameters or error minimizing methods through iterations were used for model-based 3D reconstruction. However, we proposed a method for the 3D reconstruction of primitive that consists of the segments and the center points of the segments for the reconstruction process. This method enables the reconstruction of the primitive model to be processed using only the focal length of various camera parameters during the segment reconstruction process.

Algorithms for Multi-sensor and Multi-primitive Photogrammetric Triangulation

  • Shin, Sung-Woong;Habib, Ayman F.;Ghanma, Mwafag;Kim, Chang-Jae;Kim, Eui-Myoung
    • ETRI Journal
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    • v.29 no.4
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    • pp.411-420
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    • 2007
  • The steady evolution of mapping technology is leading to an increasing availability of multi-sensory geo-spatial datasets, such as data acquired by single-head frame cameras, multi-head frame cameras, line cameras, and light detection and ranging systems, at a reasonable cost. The complementary nature of the data collected by these systems makes their integration to obtain a complete description of the object space. However, such integration is only possible after accurate co-registration of the collected data to a common reference frame. The registration can be carried out reliably through a triangulation procedure which considers the characteristics of the involved data. This paper introduces algorithms for a multi-primitive and multi-sensory triangulation environment, which is geared towards taking advantage of the complementary characteristics of spatial data available from the above mentioned sensors. The triangulation procedure ensures the alignment of involved data to a common reference frame. The devised methodologies are tested and proven efficient through experiments using real multi-sensory data.

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Minimum Temperature Mapping in Complex Terrain Considering Cold Air Drainage (냉기침강효과를 고려한 복잡지형의 최저기온 분포 추정)

  • 정유란;서형호;황규홍;황범석;윤진일
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.4 no.3
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    • pp.133-140
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    • 2002
  • Site-specific minimum temperature forecasts are critical in a short-term decision making procedure for preventive measures as well as a long-term strategy such as site selection in fruits industry. Nocturnal cold air pools frequently termed in mountainous areas under anticyclonic systems are very dangerous to the flowering buds in spring over Korea, but the spatial resolution to detect them exceeds the current weather forecast scale. To supplement the insufficient spatial resolution of official forecasts, we developed a GIS - assisted frost risk assesment scheme for using in mountainous areas. Daily minimum temperature data were obtained from 6 sites located in a 2.1 by 2.1 km area with complex topography near the southern edge of Sobaek mountains during radiative cooling nights in spring 2001. A digital elevation model with a 10 m spatial resolution was prepared for the entire study area and the cold air inflow was simulated for each grid cell by counting the number of surrounding cells coming into the processing cell. Primitive temperature surfaces were prepared for the corresponding dates by interpolating the Korea Meteorological Administration's automated observational data with the lapse rate correction. The cell temperature values corresponding to the 6 observation sites were extracted from the primitive temperature surface, and subtracted from the observed values to obtain the estimation error. The errors were regressed to the flow accumulation at the corresponding cells, delineating a statistically significant relationship. When we applied this relationship to the primitive temperature surfaces of frost nights during April 2002, there was a good agreement with the observations, showing a feasibility of site-specific frost warning system development in mountainous areas.

Design of the Gateway Function for DNP3.0 and IEC61850 (DNP 3.0과 IEC 61850 게이트웨이 기능 설계)

  • Song, Byung-Kwen;Kim, Geon-Ung
    • Journal of IKEEE
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    • v.12 no.3
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    • pp.151-157
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    • 2008
  • The DNP3.0 and the IEC61850 are the most important standards in the SCADA systems for the power. Each standard has strength and weakness, so they will coexist for a while. This paper presents a design of the gateway function between DNP3.0 and IEC61850. Both standards use object-oriented modelling methods, so, they have some similarities. However, the DNP3.0 objects are described by object number and index, and the IEC61850 objects are described by name. So there should be mapping function between the object number and index of DNP3.0 objects and the object name of IEC61850 objects. We analyse the communication profiles of both standards, and shows the service-primitive mapping table and the procedure of the gateway function.

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An Application of Screw Motions for Mechanical Assemblies (기계부품들의 조립 및 해체과정 설계를 위한 스크류이론의 응용)

  • 김재정
    • Korean Journal of Computational Design and Engineering
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    • v.2 no.1
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    • pp.60-67
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    • 1997
  • CAD systems offer a variety of techniques for designing and rendering models of static 3D objects and even of mechanisms, but relatively few tools exist for interactively specifying arbitrary movements of rigid bodies through space. Such tools are essential, not only for artistic animation, but also, for planning and demonstrating assembly and disassembly procedure of manufactured products. A rigid body motion is a continuous mapping from the time domain to a set of positions. To relieve the designers from the burden of specifying this mapping in abstract mathematical terms, combinations of simple rigid motion primitives, such as linear translations or constant axis rotations, are often used. These simple motions are planar and thus ill-suited for approximating arbitrary motions in 3D-space. Instead, we propose the screw motion primitive, a special combination of linear translations and constant axis rotations, which has a simple geometric representation that can be automatically and unambiguously computed from the starting and ending positions of the moving body. Although, any two positions may be interpolated by an infinity of motions, we chose the screw motion for its relative generality and its computational advantages. The paper covers original algorithms for computing the screw motions from interpolated positions and envelopes of swept regions to predict collisions.

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Development of Algorithm for Prediction of Bead Height on GMA Welding (GMA 용접의 최적 비드 높이 예측 알고리즘 개발)

  • 김인수;박창언;김일수;손준식;안영호;김동규;오영생
    • Journal of Welding and Joining
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    • v.17 no.5
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    • pp.40-46
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    • 1999
  • The sensors employed in the robotic are welding system must detect the changes in weld characteristics and produce the output that is in some way related to the change being detected. Such adaptive systems, which synchronise the robot arm and eyes using a primitive brain will form the basis for the development of robotic GMA(Gas Metal Arc) welding which increasingly higher levels of artificial intelligence. The objective of this paper is to realize the mapping characteristics of bead height through learning. After learning, the neural estimation can estimate the bead height desired from the learning mapping characteristic. The design parameters of the neural network estimator(the number of hidden layers and the number of nodes in a layer) are chosen from an estimation error analysis. A series of bead of bead-on-plate GMA welding experiments was carried out in order to verify the performance of the neural network estimator. The experimental results show that the proposed neural network estimator can predict the bead height with reasonable accuracy and guarantee the uniform weld quality.

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Cost-Driven Optimization of Defect-Avoidant Logic Mapping Strategies for Nanowire Reconfigurable Crossbar Architecture (Nanowire Reconfigurable Crossbar 구조를 위한 결함 회피형 로직 재할당 방식의 분석과 총 비용에 따른 최적화 방안)

  • Lee, Jong-Seok;Choi, Min-Su
    • Journal of KIISE:Computer Systems and Theory
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    • v.37 no.5
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    • pp.257-271
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    • 2010
  • As the end of photolithographic integration era is approaching fast, numerous nanoscale devices and systems based on novel nanoscale materials and assembly techniques are recently emerging. Notably, various reconfigurable architectures with considerable promise have been proposed based on nanowire crossbar structure as the primitive building block. Unfortunately, high-density sys-tems consisting of nanometer-scale elements are likely to have numerous physical imperfections and variations. Therefore, defect-tolerance is considered as one of the most exigent challenges in nanowire crossbar systems. In this work, three different defect-avoidant logic mapping algorithms to circumvent defective crosspoints in nanowire reconfigurable crossbar systems are evaluated in terms of various performance metrics. Then, a novel method to find the most cost-effective repair solution is demonstrated by considering all major repair parameters and quantitatively estimating the performance and cost-effectiveness of each algorithm. Extensive parametric simulation results are reported to compare overall repair costs of the repair algorithms under consideration and to validate the cost-driven repair optimization technique.