23002052
Transition matrices in the measurement and control of synchronous sequential machines
Abstract This paper develops a matrix approach to the solution of the measurement and control problems in synchronous sequential machines. The control problem in sequential machines is concerned with finding input sequences that take a given machine from a known initial state to a predesignated terminal state. There may be many different measurement problems of interest in sequential machines. One important measurement problem is the identification of the unknown initial state of the machine, called the initial-state identification problem or diagnosing problem; another important measurement problem is the identification of the terminal state of the machine, known as the terminal-state identification problem or homing problem, of which a special case is the synchronizing problem. These measurement problems may be solved by applying predetermined input sequences to the machine and noting the resulting output sequences. The conventional approach to the solution of these measurement and control problems is to make use of the information contained in the transition table of the machine in conjunction with its response tree, which is basically an exhaustive tree search process. In the present paper, instead of using the transition table and the corresponding response tree, we use only the transition matrix representation of the machine and its higher order forms to solve the aforementioned problems. The suggested approach is very systematic and completely algorithmic, and thus lends itself to easy computer implementation.
17657159
A Chinese-character thinning algorithm based on global features and contour information
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.
42618487
Handwritten Chinese Character Recognition Using Stroke Structural Sequence Code
45057829
Preclassification of handwritten Chinese characters based on basic stroke substructures
A method for preclassification of handwritten Chinese characters is presented. A set of basic stroke substructures is defined using the consistent stroke connection relations. A knowledge guided recognition process is employed to identify the types of the extracted basic stroke substructures found in a handwritten character. Then a 1-D character coding scheme is given to represent the character and the code can be also used for character preclassification.
1822288
Incremental model building of polyhedral objects using structured light
Abstract A vision method using active sensing to construct the complete geometric model of a polyhedral object is presented. The model is constructed incrementally from multiple views. Each view produces a partial object model. Three different methods are described for integrating all the partial models into a final complete model. Theorems regarding the sufficient number of views required and how these views can be set up during the reconstruction process are also given. From theoretical analysis and experimental results, our method is shown to produce an accurate object geometric model, not just an approximate model. Furthermore, it does not rely on a precise object-to-image space transformation. Moreover, the method is fast and robust, since the basic geometric entity it derives is a face instead of a point.
2042582
Pose determination of a cylinder using reprojection transformation
Extracting useful and robust feature points from a cylinder image for 3D pose determination is a relatively difficult task, since there are no feature points or lines on the cylinder. In this study, a key vector from a cylinder image is found to yield a transformation. The cylinder is then ''reprojected'' from the original image to obtain a new image using the transformation. The new image reveals some important features capable of determining the 3D cylinder position robustly. The proposed method can yield an exact and analytical solution without the requirement of using any special marks, extra equipment or assumptions. Additionally, a problem in which both circles on the cylinder are not completely visible due to the viewing angle can be resolved by this method. Finally, experimental results are provided to verify the theory and show the robustness of our method.
701
Common-Face Embeddings of Planar Graphs
Given a planar graph $\Ggg$ and a sequence ${\CC}_1,\ldots,{\CC}_q$, where each ${\CC}_i$ is a family of vertex subsets of $\Ggg$, we wish to find a plane embedding of $\Ggg$, if any exists, such that, for each $i\in\{1,\ldots,q\}$, there is a face Fi in the embedding whose boundary contains at least one vertex from each set in CCi. This problem has applications in the recovery of topological information from geographical data and the design of constrained layouts in VLSI. Let $\inputsize$ be the input size, i.e., the total number of vertices and edges in $\Ggg$ and the families CCi, counting multiplicity. We show that this problem is NP-complete in general. We also show that it is solvable in $O(\inputsize\log \inputsize)$ time for the special case in which, for each input family CCi, each set in CCi induces a connected subgraph of the input graph $\Ggg$. Note that the classical problem of simply finding a planar embedding is a further special case of this case with q=0. Therefore, the processing of the additional constraints CC1, . . .,CCq incurs only a logarithmic factor of overhead.
1877127
Fault tolerant high performance computing by a coding approach
As the number of processors in today's high performance computers continues to grow, the mean-time-to-failure of these computers are becoming significantly shorter than the execution time of many current high performance computing applications. Although today's architectures are usually robust enough to survive node failures without suffering complete system failure, most today's high performance computing applications can not survive node failures and, therefore, whenever a node fails, have to abort themselves and restart from the beginning or a stable-storage-based checkpoint.This paper explores the use of the floating-point arithmetic coding approach to build fault survivable high performance computing applications so that they can adapt to node failures without aborting themselves. Despite the use of erasure codes over Galois field has been theoretically attempted before in diskless checkpointing, few actual implementations exist. This probably derives from concerns related to both the efficiency and the complexity of implementing such codes in high performance computing applications. In this paper, we introduce the simple but efficient floating-point arithmetic coding approach into diskless checkpointing and address the associated round-off error issue. We also implement a floating-point arithmetic version of the Reed-Solomon coding scheme into a conjugate gradient equation solver and evaluate both the performance and the numerical impact of this scheme. Experimental results demonstrate that the proposed floating-point arithmetic coding approach is able to survive a small number of simultaneous node failures with low performance overhead and little numerical impact.
30786237
Spanning closed trails in graphs
Abstract Let G be a 2-edge-connected simple graph on n >;95 vertices. Let l be the number of vertices of degree 2 in G . We prove that if l n ⧸5−19 and if, for every edge uvϵE ( G ), d ( v )+ d ( v )⩾2 n ⧸5−2, then exactly one of the following holds: (a) G has a spanning closed trail; (b) G can be contracted to K 2, c −2 , where c ⩽ max {5, 3+ l } is an odd number. An example shows that if a graph satisfies the conditions above except that it has too many vertices of degree 2, then the conclusion fails. This result is related to a conjecture of Benhocine et al. (1986), recently proved by Veldman. We obtain some other related results.
52859343
Towards rate-distortion tradeoff in real-time color video coding
In this paper, we address to the key problem in real-time video coding, the rate-distortion tradeoff. We found that the distribution of the integer transform coefficients in H.264 color video coding can be approximated by Laplacian distribution but the rate-distortion characteristics should be modelled for the luminance and chrominance components separately. So we propose separable rate-distortion models for color video coding. The feedback from the encoder buffer is analyzed by a control-theoretic adaptation approach. To achieve smooth video quality and satisfy the delay constraints in real-time applications, a novel rate distortion tradeoff controller is employed. Simulations results demonstrate that the proposed approach can achieve smooth video quality without sacrificing overall quality while efficiently utilize the bandwidth without buffer overflow or underflow.
27655532
On the Planar Two-Watchtower Problem
In this paper we study the following planar two-watchtower problem: given a terrain (X-monotone chain) T with n vertices, locate two vertical segments (watchtowers) uv and u′v′ which have to be erected on T such that every point on T is visible to the top of either watchtowers (u or u′) and the maximum height of uv, u′v′ is minimized. We present an O(n4) time algorithm to solve the discrete version of this problem when v, v′ must be on some vertices of T. Under a mild condition on solving a special cubic equation with three bounded variables in O(f3) time we can also generalize the algorithm to solve the general problem in O(n4 +n3f3) time. Using parametric search, the discrete problem can be solvedin O(n3 log2 n) time and the general problem can be solvedin O(n4 log2 n) time.