Browsing by Author "LIN, JC"

Now showing 1 - 16 of 16

A GENERALIZED OPTIMAL PATH-SELECTION MODEL FOR STRUCTURAL PROGRAM TESTING
(1989-07-01)
WANG, HS
;
HSU, SR
;
LIN, JC
;
資訊工程學系
;
Department of Computer Science
COLOR IMAGE COMPRESSION BY MOMENT-PRESERVING AND BLOCK TRUNCATION CODING TECHNIQUES
(1994)
YANG, CK
;
LIN, JC
;
TSAI, WH
;
資訊工程學系
;
Department of Computer Science
COLOR IMAGE SHARPENING BY MOMENT-PRESERVING TECHNIQUE
(1995-09-01)
YANG, CK
;
WU, TC
;
LIN, JC
;
TSAI, WH
;
資訊工程學系
A new approach to sharpening color images using the moment-preserving technique is proposed, An input image is processed pixel by pixel. By preserving some color moments of the n x n neighborhood of each pixel, analytic formulas are derived to compute two sets of (R, G, B) tristimulus values, and one of them is assigned to the pixel as the sharpening result. Cases with one or more uniform color components in the neighborhood are also treated. The proposed method preserves spatial details, and requires little memory and small computational load, The proposed sharpening operation can also be applied iteratively to the input image to get better sharpening effect. Experimental results show that the proposed approach is effective for color image sharpening.
DETECTING NUMBER OF FOLDS BY A SIMPLE MATHEMATICAL PROPERTY
(1994-11-01)
LIN, JC
;
TSAI, WH
;
CHEN, JA
;
交大名義發表
;
資訊工程學系
Based on a simple mathematical property, a simple method is proposed for detecting the number of folds n contained in a given rotationally symmetric shape. Skills to overcome the difficulty caused by sampling and rounding errors are also discussed. Experimental results are included to show the feasibility of this new method. As for shape orientation, it is just a by-product of the proposed method because no extra computation load is needed to get the orientation.
DETECTION OF ROTATIONALLY SYMMETRICAL SHAPE ORIENTATIONS BY FOLD-INVARIANT SHAPE-SPECIFIC POINTS
(1992-05-01)
LIN, JC
;
CHOU, SL
;
TSAI, WH
;
資訊工程學系
;
Department of Computer Science
Two new types of shape-specific points, called fold-invariant centroid (FIC) and fold-invariant radius weighted mean (FIRWM), are introduced for detecting the orientations of rotationally symmetric shapes. A given rotationally symmetric shape is first transformed into a new fold-invariant shape. The centroid and the radius weighted mean of the new shape are then transformed back to obtain the proposed FIC and FIRWM, respectively. FIC and FIRWM points are proved to be invariant to translation, rotation and scaling, and so can be used for matching rotationally symmetric shapes. Using the proposed fold-invariant shape-specific points to detect the orientations of rotationally symmetric shapes is easier to implement than that of using the fold principal axes. Some illustrative examples and a method to avoid the case where the proposed fold-invariant shape-specific points are too close to the centroid are also given.
DOWNLINK POWER-CONTROL ALGORITHMS FOR CELLULAR RADIO SYSTEMS
(1995-02-01)
LEE, TH
;
LIN, JC
;
SU, YT
;
電控工程研究所
;
電信工程研究所
Power control is an effective technique to reduce cochannel interference and increase capacity for cellular radio systems, Optimum centralized power control can minimize the outage probability, but requires the information of all link gains in real time, which is very difficult to successfully implement for a large system; besides, the computational complexity of an optimum power control algorithm makes it impractical for real implementations. In this paper, we propose some centralized power control algorithms with reasonable computational complexity, One of the algorithms, called the SMIRA algorithm, has an outage probability that is very close to the minimum, We also study a class of distributed power control algorithms that can achieve a balanced carrier-to-interference ratio with probability one, Among the class of algorithms, we found that the one proposed in [6] gives the minimum outage probability.
FAST LEG CODEBOOK GENERATOR FOR ETC IMAGE COMPRESSION
(1995-08-17)
WU, KS
;
LIN, JC
;
交大名義發表
;
資訊工程學系
;
National Chiao Tung University
When the high-mean and low-mean generated by the BTC image compression technique are to be quantised using VQ, the computation time required to search for the nearest centroid can be reduced significantly using the proposed method. Experiments comparing the full-search and EHPM algorithms demonstrate this.
FEATURE-PRESERVING CLUSTERING OF 2-D DATA FOR 2-CLASS PROBLEMS USING ANALYTICAL FORMULAS - AN AUTOMATIC AND FAST APPROACH
(1994-05-01)
LIN, JC
;
TSAI, WH
;
交大名義發表
;
資訊工程學系
;
National Chiao Tung University
We propose in this correspondence a new method to perform two-class clustering of 2-D data in a quick and, automatic way by preserving certain features of the input data. The method is analytical, deterministic, unsupervised, automatic, and noniterative. The computation time is of order n if the data size is n, and hence much faster than any other method which requires the computation of an n-by-n dissimilarity matrix. Furthermore, the proposed method does not have the trouble of guessing initial values. This new approach is thus more suitable for fast automatic hierarchical clustering or any other fields requiring fast automatic two-class clustering of 2-D data. The method can be extended to cluster data in higher dimensional space. A 3-D example is included.
FOLD PRINCIPAL AXIS - A NEW TOOL FOR DEFINING THE ORIENTATIONS OF ROTATIONALLY SYMMETRICAL SHAPES
(1991-02-01)
CHOU, SL
;
LIN, JC
;
TSAI, WH
;
資訊工程學系
;
Department of Computer Science
A new type of principal axis, namely, fold principal axis, is introduced in this paper, which can be used to define the orientations of rotationally symmetric shapes. A given shape is first transformed into a new shape on which the well-defined traditional principal axis is detected. The traditional principal axis is then transformed back to obtain the proposed fold principal axes of the given shape. The properties of such axes, including the uniqueness, existence, and invariance under rotation, translation, and scaling, are investigated. Some illustrative examples are also given.
FORCED VIBRATION OF FLEXIBLE BODY SYSTEMS - A DYNAMIC STIFFNESS METHOD
(1993-10-01)
LIU, TS
;
LIN, JC
;
交大名義發表
;
機械工程學系
;
National Chiao Tung University
Due to the development of high speed machinery, robots, and aerospace structures, the research of flexible body systems undergoing both gross motion and elastic deformation has seen increasing importance. The finite element method and modal analysis are often used in formulating equations of motion for dynamic analysis of the systems which entail time domain, forced vibration analysis. This study develops a new method based on dynamic stiffness to investigate forced vibration of flexible body systems. In contrast to the conventional finite element method, shape functions and stiffness matrices used in this study are derived from equations of motion for continuum beams. Hence, the resulting shape functions are named as dynamic shape functions. By applying the dynamic shape functions, the mass and stiffness matrices of a beam element are derived. The virtual work principle is employed to formulate equations of motion. Not only the coupling of gross motion and elastic deformation, but also the stiffening effect of axial forces is taken into account. Simulation results of a cantilever beam, a rotating beam, and a slider crank mechanism are compared with the literature to verify the proposed method.
MICROSTRUCTURE AND PROPERTIES OF NI-ZN FERRITES SINTERED FROM SLIP CAST COLLOIDALLY PRECIPITATED PARTICLES
(1989-11-01)
TSENG, TY
;
LIN, JC
;
交大名義發表
;
工學院
;
National Chiao Tung University
POWER-CONTROL ALGORITHM FOR CELLULAR RADIO SYSTEMS
(1994-02-03)
LIN, JC
;
LEE, TH
;
SU, YT
;
電控工程研究所
;
電信工程研究所
In a recent paper, Zander presented an optimum transmitter power control scheme to minimise the outage probability for cellular systems and proposed the stepwise removal algorithm (SRA) for use in practical implementations. In the Letter, the authors present a new power control algorithm which considers the transmitter power together with fink gams. The algorithm provides better outage probability with only a negligible increase in computational complexity.
PREPARATION OF FINE-GRAINED NI-ZN FERRITES
(1989-03-01)
TSENG, TY
;
LIN, JC
;
交大名義發表
;
National Chiao Tung University
The effect of imperfect power control on outage probability in a cellular mobile system
(1995)
LIN, JC
;
LIN, YC
;
LEE, TH
;
SU, YT
;
電控工程研究所
UNIVERSAL PRINCIPAL AXES - AN EASY-TO-CONSTRUCT TOOL USEFUL IN DEFINING SHAPE ORIENTATIONS FOR ALMOST EVERY KIND OF SHAPE
(1993-04-01)
LIN, JC
;
交大名義發表
;
資訊工程學系
;
National Chiao Tung University
;
Department of Computer Science
A convenient tool for defining shape orientations called universal principal axes is introduced. These axes are formed of half lines starting from the shape centroid, with their directional angles expressed as functions of the polar angle of the first non-zero complex number encountered in the sequence integral integral(x + iy)l dA with l = 2, 3, 4,..., provided that the integration domain is taken to be the given two-dimensional (2D) shape and the origin is assumed to be the shape centroid. Universal principal axes are shown to be independent of the translation, scaling, and rotation of the coordinate system used, and they are therefore qualified in defining shape orientations. A major benefit of using the proposed universal principal axes is that they exist for almost every kind of shape. Another benefit is that there is no need to judge in advance whether a given shape is mirror-symmetric, rotationally symmetric, irregular, etc. Moreover, in the case of rotationally symmetric shapes, the universal principal axes make the preprocessing procedure for detecting the number of folds contained in the given shape unnecessary although such procedure is essential for many existing tools designed to define orientations of rotationally symmetric shapes. Defining shape orientations by universal principal axes is therefore quite convenient. An algorithm describing the construction of universal principal axes and several examples showing the detected universal principal axes for some shapes of distinct types are given. The relationship between universal and conventional principal axes is also discussed.
USE OF RADIUS WEIGHTED MEAN TO CLUSTER 2-CLASS DATA
(1994-05-12)
YANG, CY
;
LIN, JC
;
交大名義發表
;
資訊工程學系
;
National Chiao Tung University
A new method using the radius weighted mean to cluster two-class data is proposed. Experiments show that the clustering results are good, the computation is fast, and the method is easy to implement. The method can be applied to block truncation coding, codebook generation, and decision tree construction.