• 제목/요약/키워드: Data representation

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High Representation based GAN defense for Adversarial Attack

  • Sutanto, Richard Evan;Lee, Suk Ho
    • International journal of advanced smart convergence
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    • 제8권1호
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    • pp.141-146
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    • 2019
  • These days, there are many applications using neural networks as parts of their system. On the other hand, adversarial examples have become an important issue concerining the security of neural networks. A classifier in neural networks can be fooled and make it miss-classified by adversarial examples. There are many research to encounter adversarial examples by using denoising methods. Some of them using GAN (Generative Adversarial Network) in order to remove adversarial noise from input images. By producing an image from generator network that is close enough to the original clean image, the adversarial examples effects can be reduced. However, there is a chance when adversarial noise can survive the approximation process because it is not like a normal noise. In this chance, we propose a research that utilizes high-level representation in the classifier by combining GAN network with a trained U-Net network. This approach focuses on minimizing the loss function on high representation terms, in order to minimize the difference between the high representation level of the clean data and the approximated output of the noisy data in the training dataset. Furthermore, the generated output is checked whether it shows minimum error compared to true label or not. U-Net network is trained with true label to make sure the generated output gives minimum error in the end. At last, the remaining adversarial noise that still exist after low-level approximation can be removed with the U-Net, because of the minimization on high representation terms.

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

  • 이승훈;한순흥
    • 한국CDE학회논문집
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    • 제18권3호
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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.

기하학적 모형을 위한 꼭지점 중심의 쿼드트리와 옥트리 (Vertex Quadtree and Octree for Geometric Modeling : Their Average Storage and Time Complexities)

  • 이현찬;이철동
    • ETRI Journal
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    • 제11권1호
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    • pp.109-122
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    • 1989
  • We developed new quadtree and octree representation schemes which reduce the storage requirements from exponential to polynomial. The new schemes not only lessen the large storage requirements of the existing quadtree and octree representation schemes but guarantee an exact representation of the original object. These are made possible by adopting a new set of termination conditions that ensure finiteness of the quadtree and octree during the decomposition. These new data structures are analyzed theoretically and tested empirically. For space complexity, we analyzed its best case, worst case, and average case. Given an $n_e$-gon, we show that the expected number of nodes in our quadtree isO($$$n_e^1.292$) For a polyhedron with $n_f$ faces, the expected number of nodes in the new octree is O($$$n_f^1.667$). For time complexity, we again analyzed the best, worst, and average cases for constructing such quadtree and octree and find the average to be the same as those of the space complexity. Finally, random $n_e$- gons are generated as test data. Regression equations are fitted and are shown to support the claims on the average case performance.

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Constrained Sparse Concept Coding algorithm with application to image representation

  • Shu, Zhenqiu;Zhao, Chunxia;Huang, Pu
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제8권9호
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    • pp.3211-3230
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    • 2014
  • Recently, sparse coding has achieved remarkable success in image representation tasks. In practice, the performance of clustering can be significantly improved if limited label information is incorporated into sparse coding. To this end, in this paper, a novel semi-supervised algorithm, called constrained sparse concept coding (CSCC), is proposed for image representation. CSCC considers limited label information into graph embedding as additional hard constraints, and hence obtains embedding results that are consistent with label information and manifold structure information of the original data. Therefore, CSCC can provide a sparse representation which explicitly utilizes the prior knowledge of the data to improve the discriminative power in clustering. Besides, a kernelized version of our proposed CSCC, namely kernel constrained sparse concept coding (KCSCC), is developed to deal with nonlinear data, which leads to more effective clustering performance. The experimental evaluations on the MNIST, PIE and Yale image sets show the effectiveness of our proposed algorithms.

An Efficient Type Codec for Point Data in Lightweight Applications Scene Representation (LASeR)

  • Joung, Ye-Sun;Cha, Ji-Hun;Cheong, Won-Sik;Lim, Young-Kwon;Kim, Kyu-Heon
    • ETRI Journal
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    • 제27권6호
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    • pp.818-821
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    • 2005
  • Recently, MPEG has opened activity to standardize scene representation for lightweight applications such as in mobile phones. The standard is named lightweight applications scene representation (LASeR) and can be applied to improve and make efficient rich media applications and services on mobile devices. In this standard, we proposed an efficient type codec for point data to maximize the bit efficiency of LASeR. In this paper, we describe the new method and the test results of the proposed scheme.

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IFC 3차원 건축모델표준과 ISO/STEP AP202도면표준의 2차원 형상정보 연계방안 (Harmonization of IFC 3D Building Model Standards and ISO/STEP AP202 Drawing Standards for 2D Shape Data Representation)

  • 원지선;임경일;김성식
    • 한국CDE학회논문집
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    • 제11권6호
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    • pp.429-439
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    • 2006
  • The purpose of this study is to support the integration from current 2D drawing-based design to future 3D model-based design. In this paper, an important theme is the combination between the STEP-based 2D drawing standards (i.e., AP202) and the IFC-based 3D building model standards. To achieve the purpose, two methodologies are proposed as follows: the development of IFC extension model for the 2D shape data representation by harmonizing ISO/STEP AP202; and the development of mapping solution between IFC 2D extension model and KOSDIC by constructing the exchange scenario for 2D shape data representation. It is expected that the proposed IFC2X2 2D extension model and mapping solution will offer the basis of development of the integrated standards model in AEC industry.

비다양체 형상 모델링을 위한 간결한 경계 표현 및 확장된 오일러 작업자 (Compact Boundary Representation and Generalized Eular Operators for Non-manifold Geometric Modeling)

  • 이상헌;이건우
    • 한국CDE학회논문집
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    • 제1권1호
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    • pp.1-19
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    • 1996
  • Non-manifold topological representations can provide a single unified representation for mixed dimensional models or cellular models and thus have a great potential to be applied in many application areas. Various boundary representations for non-manifold topology have been proposed in recent years. These representations are mainly interested in describing the sufficient adjacency relationships and too redundant as a result. A model stored in these representations occupies too much storage space and is hard to be manipulated. In this paper, we proposed a compact hierarchical non-manifold boundary representation that is extended from the half-edge data structure for solid models by introducing the partial topological entities to represent some non-manifold conditions around a vertex, edge or face. This representation allows to reduce the redundancy of the existing schemes while full topological adjacencies are still derived without the loss of efficiency. To verify the statement above, the storage size requirement of the representation is compared with other existing representations and present some main procedures for querying and traversing the representation. We have also implemented a set of the generalized Euler operators that satisfy the Euler-Poincare formula for non-manifold geometric models.

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한의학의 증상표현을 위한 방법론 (A Methodology for Representation of Clinical Data in Oriental Medicine)

  • 박경모;박종현
    • 동의생리병리학회지
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    • 제16권5호
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    • pp.845-850
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    • 2002
  • This paper suggest a methodology for representation of findings which can be called as signs and symptoms. A finding consists of unit signs and unit symptoms, and moreover findings which appear in one individual patient have so many different relationship each other. So, it is nat appropriate to list all of possible findings as medical standard or to fill findings as independent things in paper for medical record. We try to distinguish finding item from finding list, and suggest the methodology by which we can make finding list from finding items. That is, we suggest finding item[Concept], value types, relationship, logical operator, and syntax as a component of representation. And by using urinary symptom, we make the example for representation methodology. Finally, we mention the background knowledge, brief research process of related area.

U-TURN을 포함한 가로망 표현 및 최단경로의 구현 (Network Representation Schemes for U-TURN and Implementation in the Vine-Based Dijkstra Shortest Path Algorithm)

  • 최기주
    • 대한교통학회지
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    • 제13권3호
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    • pp.35-52
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    • 1995
  • This paper reviews both network representation schemes of transportation network and algorithms for findings the shortest path between two points in the network. Two types of network representation schmes for considering U-Turn have been proposed along with some modifications of the vine-based Dijkstra shoretest path algorithm. The traditional Sioux-Fall network has been chosen and modified with the introduction of left-turn prohibitions and U-Turns for the purpose of evaluating the peroformance of two modified algorithms and network representation schemes(NA1 an d NA2 ). This type of modification in both network representation scheme (including network data) and algorithms is not only supposed to be needed for route guidance but supposed to contribute to finding more realistic path and estimating more accurate traffic voulume thorughout the entire network.

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임의 형상의 복합재 모델링을 위한 CSG 기반 표현 (CSG-based Representation for Free-form Heterogeneous Object Modeling)

  • 신기훈;이진구
    • 한국CDE학회논문집
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    • 제11권4호
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    • pp.235-245
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    • 2006
  • This paper proposes a CSG-based representation scheme for heterogeneous objects including multi-material objects and Functionally Graded Materials (FGMs). In particular, this scheme focuses on the construction of complicated heterogeneous objects guaranteeing desired material continuities at all the interfaces. In order to create various types of heterogeneous primitives, we first describe methods for specifying material composition functions such as geometry-independent, geometry-dependent functions. Constructive Material Composition (CMC) and corresponding heterogeneous Boolean Operators (e.g. material union, difference, intersection. and partition) are then proposed to illustrate how material continuities are dealt with. Finally, we describe the model hierarchy and data structure for computer representation. Even though the proposed scheme alone is sufficient for modeling all sorts of heterogeneous objects, the proposed scheme adopts a hybrid representation between CSG and decomposition. That is because hybrid representation can avoid the unnecessary growth of binary trees.