Browsing by Author "CHEN, Z"

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A CHINESE-CHARACTER THINNING ALGORITHM-BASED ON GLOBAL FEATURES AND CONTOUR INFORMATION
(1995-04-01)
LIN, JY
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CHEN, Z
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資訊科學與工程研究所
;
Institute of Computer Science and Engineering
This paper proposes a method of using run-length coding to perform thinning. First, we construct graphs from characters. The attributes (vertical lines, horizontal lines or points) of each node in the graph are determined according to the node's relationship to the nodes above and below it (we will refer to these relationships as global features) and the black runs within the node. Intersections between two adjacent segments are determined on the basis of the graph constructed and contour information. The thinning algorithm thus employs global features and contour information to produce a more accurate skeleton.
A DGR METHOD FOR EXTRACTING THE TOPOLOGY OF AN UPPER-HALF PROFILE OF A TURNED PART FROM CAD DATA
(1991-01-01)
CHEN, SL
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CHEN, Z
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LI, RK
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資訊工程學系
;
Department of Computer Science
For a symmetrical turned part, a 2D upper-half profile is usually the input for planning functions such as turning feature extraction, process planning, and NC code generation. Current approaches to extract the topology of an upper-half profile from 2D CAD engineering drawings are heuristic and have limitations. In this paper, the drawing view cluster method and Drawing Graph Representation (DGR) method are proposed. The former has been developed to cluster front view entities into groups if the input to the activity is more than one view. Using the DGR, rules are developed to identify internal entities, external entities, types of internal profile and possible redundant entities. An example is evaluated to demonstrate the methods.
A FLEXIBLE PARALLEL ARCHITECTURE FOR RELAXATION LABELING ALGORITHMS
(1992-05-01)
LIN, SY
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CHEN, Z
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交大名義發表
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資訊工程學系
;
National Chiao Tung University
The design of a flexible parallel architecture for both the discrete relaxation labeling (DRL) algorithm and the probabilistic relaxation labeling (PRL) algorithm is addressed. Through the analysis of parallelism in the computational models of both algorithms, the parallel execution of the algorithms on a flexible parallel architecture is presented. Three basic types of parallel operations are performed in the architecture: simultaneous, pipeline, and systolic. An illustrative example is used to show how the DRL algorithm can be executed on the parallel architecture. In doing so the processing element (PE) organization and the combiner organization of the architecture are described. The same architecture with programmable functional units is shown to be able to execute the PRL algorithm, too. The performance comparisons between the proposed architecture and some other existing ones are also given.
A NEW ALGORITHM AND ITS VLSI ARCHITECTURE DESIGN FOR CONNECTED COMPONENT LABELING
(1994)
JEAN, SD
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LIU, CM
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CHANG, CC
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CHEN, Z
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資訊工程學系
A PARALLEL ARCHITECTURE FOR PROBABILISTIC RELAXATION OPERATIONS ON IMAGES
(1990)
CHEN, Z
;
LIN, SY
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CHEN, YY
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交大名義發表
;
資訊工程學系
A SIMPLE VISION ALGORITHM FOR 3-D POSITION DETERMINATION USING A SINGLE CALIBRATION OBJECT
(1989)
CHEN, Z
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TSENG, DC
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LIN, JY
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交大名義發表
;
資訊工程學系
ALGORITHM FOR FINDING ALL MAXIMAL COMPLETE SUBGRAPHS AND AN ESTIMATE OF THE ORDER OF COMPUTATIONAL COMPLEXITY
(1978)
DAS, SR
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SHENG, CL
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CHEN, Z
;
交大名義發表
;
資訊工程學系
AN EFFECTIVE SEARCH APPROACH TO CAMERA PARAMETER-ESTIMATION USING AN ARBITRARY PLANAR CALIBRATION OBJECT
(1993-05-01)
CHEN, Z
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WANG, CM
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HO, SY
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交大名義發表
;
資訊科學與工程研究所
In this paper we shall present a new method for camera parameter estimation using an arbitrary planar calibration object. We begin with an approximate model for the perspective view and give a parameter-free normalized-line-segment-ratio relationship between the corresponding reference and sensed views. This representation makes parameter decoupling possible and reduces the library dimension from six to one. Then the estimation problem can be viewed as a library search problem. Various mechanisms are provided to reduce the library search time, including (a) library partition by clustering, (b) sensed cluster identification by binary search, and (c) sequential testing for view matching using sorted features. In addition, feature perturbation is also considered to achieve better robustness against feature noise. Both computer-generated and real data are included in experiments, illustrating how our method works.
APPROACH TO MICROPROGRAM OPTIMIZATION THROUGH BIT DIMENSION REDUCTION IN A GIVEN CONTROL STORE SPECIFICATION
(1979)
DAS, SR
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CHEN, Z
;
SHENG, CL
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資訊工程學系
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Department of Computer Science
AUTOMATIC 3D MACHINING FEATURE-EXTRACTION FROM 3D CSG SOLID INPUT
(1990-06-01)
PERNG, DB
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CHEN, Z
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LI, RK
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交大名義發表
;
資訊科學與工程研究所
AUTOMATIC CONSISTENCY VERIFICATION OF MECHANICAL CAD FILES
(1993-07-01)
PERNG, DB
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CHEN, Z
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WU, JS
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資訊科學與工程研究所
;
工業工程與管理學系
A system for automatic verification of the exactness of the CAD files of a mechanical part with planar and cylindrical faces through 3D part reconstruction is described. A set of consistency checking rules are specified to facilitate the part reconstruction. The system not only reconstructs the 3D geometry from a correct drawing file, but also produces adequate error messages to aid the designer to make corrections. We shall present our method with illustrations. Experimental results indicate that the set of checking rules is very useful and the system is very effective.
AUTOMATIC RECONSTRUCTION OF 3D SOLID OBJECTS FROM 2D ORTHOGRAPHIC VIEWS
(1988)
CHEN, Z
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PERNG, DB
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交大名義發表
;
資訊工程學系
;
National Chiao Tung University
CAD-BASED AUTOMATED MACHINABLE FEATURE-EXTRACTION
(1993)
LIU, CH
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CHEN, Z
;
資訊科學與工程研究所
;
Institute of Computer Science and Engineering
CAMERA PARAMETER DETERMINATION FROM A SINGLE VIEW OF A GENERAL PLANAR CALIBRATION OBJECT
(1994)
WANG, CM
;
CHEN, Z
;
資訊科學與工程研究所
;
Institute of Computer Science and Engineering
COMPLEXITY AND PERFORMANCE OF A GRAPH-THEORY ALGORITHM FOR CLUSTER-ANALYSIS
(1983)
DAS, SR
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CHEN, Z
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LEE, SY
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LIN, T
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SHENG, CL
COMPUTER VISION FOR ROBUST 3D AIRCRAFT RECOGNITION WITH FAST LIBRARY SEARCH
(1991)
CHEN, Z
;
HO, SY
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交大名義發表
;
資訊科學與工程研究所
;
National Chiao Tung University
A fast but accurate classification method is presented which takes the fundamental problems of aircraft recognition in 3D space into consideration. Elliptic Fourier descriptors are used for aircraft classification and pose determination from a two-dimensional image recorded at an arbitrary viewing angle. The computation model of the nearest neighbor classification rule (or, simply, NNR) is analysed to come up with proper necessary conditions used by our method for reducing the set of near neighbors of a test projection for a fast partial library search. On the other hand, our method is robust to noise by incorporating a perturbation analysis of feature variation into the classifier design. Both graphics-generated data and real data of five aircraft have been used to demonstrate the applicability of the new method. The results indicate that the method is almost as accurate as the NNR method, but is much faster. The method is also shown to outperform other existing classification methods including the decision-tree classification method.
COMPUTING LOCATION AND ORIENTATION OF POLYHEDRAL SURFACES USING A LASER-BASED VISION SYSTEM
(1991-12-01)
TSENG, DC
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CHEN, Z
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資訊工程學系
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Department of Computer Science
A laser-based vision system for computing the location and orientation of 3-D polyhedral surfaces is proposed. In this system, an expanded laser beam Passes through a code plate marked with equally spaced vertical and horizontal lines and impinges on a polyhedral object to create a spatial-encoded image for analysis. Then, based on the vanishing points or the directly available line directions of the perceived grid lines on the polyhedral surface, the polyhedral surface orientation can be inferred. In the meantime, the given dimensions of the grid pattern on the Plate are used to estimate the depth information of the polyhedral surfaces. More importantly, we shall solve the noise problem that occurs in the real image by a least squares estimation method and an iterative refinement method based on a geometric constraint criterion. Experiments are conducted to provide practical insight into the method. The experimental results indicate that the method is remarkably accurate and stable.
DESIGN OF IMPROVED FAILURE DETECTION EXPERIMENTS IN SYNCHRONOUS SEQUENTIAL-MACHINES BASED ON TERMINAL MEASUREMENTS
(1979)
DAS, SR
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CHEN, Z
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WU, SM
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LEE, SY
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BHATTACHARYYA, A
EASILY TESTABLE SEQUENTIAL-MACHINES WITH EXTRA INPUTS AND EXTRA OUTPUTS
(1980)
DAS, SR
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CHEN, Z
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DAI, YL
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交大名義發表
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資訊工程學系
FAST RECONSTRUCTION OF 3D-MECHANICAL PARTS FROM 2D-ORTHOGRAPHIC VIEWS WITH RULES
(1992-01-01)
CHEN, Z
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PERNG, DB
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CHEN, CJ
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WU, CS
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資訊科學與工程研究所
A fast algorithm for 3D part reconstruction from a 3-view drawing is presented. A set of rules are specified to facilitate the part reconstruction. The main idea is to use the rules to determine the truth or falsity of 3D faces and the coexistence or non-coexistence relationships between 3D faces. In a graph search formulation of the reconstruction problem, these rules can reduce remarkably (a) the graph search space, (b) the occurrence of backtracking in the search and (c) the branching factor of the tree expansion. We shall present our method with illustrations. Currently we limit the type of part to be plane-faced for presentation simplicity, although we are extending our method to cover the cylindrical parts, too. Experimental results indicate the set of rules is useful and our reconstruction method is very effective.