6155777
Claws contained in all n-tournaments
Abstract We prove that any claw of order n with degree d≤ 3 8 n is n-unavoidable, which means that any tournament of order n contains it as a subdigraph. A simple corollary is that any tournament has a directed Hamiltonian path.
28342911
A matching game
Abstract We consider the following 2-person game playing on K n,n . Two players, maker and breaker, alternately take a previously untaken edge from K n,n , the complete bipartite graph of order 2 n . The game continues until all the edges of K n,n have been taken. Then the edges taken by maker induce a subgraph of K n,n , which is denoted by G ( M ). At the end of the game, we calculate the number of edge-disjoint perfect matchings of G ( M ), and denote this number by m ( M ). The maker's aim is to make this number big and the breaker's is to force it small. We will prove the following result: For any given η >0, there exists N ( η ), such that if n ⩾ N ( η ), then maker has a strategy to guarantee m(M)⩾( 1 2 −η)n .
176930
Face detection and synthesis using Markov random field models
Markov random fields (MRFs) are proposed as viable stochastic models for the spatial distribution of gray levels for images of human faces. These models are trained using data bases of face and non-face images. The trained MRF models are then used for detecting human faces in test images. We investigate the performance of the face detection algorithm for two classes of MRFs given by the first- and second-order neighborhood systems. From the cross validation results and from actual detection in real images, it is shown that the second-order model makes fewer false detections. We also investigate the possibility of increasing our training data base of faces by simulating face-like images from the trained MRFs. The performance of the re-trained MRFs based on added face-like images is compared to the original training data base.
17264261
Matching 2.5D face scans to 3D models
The performance of face recognition systems that use two-dimensional images depends on factors such as lighting and subject's pose. We are developing a face recognition system that utilizes three-dimensional shape information to make the system more robust to arbitrary pose and lighting. For each subject, a 3D face model is constructed by integrating several 2.5D face scans which are captured from different views. 2.5D is a simplified 3D (x,y,z) surface representation that contains at most one depth value (z direction) for every point in the (x, y) plane. Two different modalities provided by the facial scan, namely, shape and texture, are utilized and integrated for face matching. The recognition engine consists of two components, surface matching and appearance-based matching. The surface matching component is based on a modified iterative closest point (ICP) algorithm. The candidate list from the gallery used for appearance matching is dynamically generated based on the output of the surface matching component, which reduces the complexity of the appearance-based matching stage. Three-dimensional models in the gallery are used to synthesize new appearance samples with pose and illumination variations and the synthesized face images are used in discriminant subspace analysis. The weighted sum rule is applied to combine the scores given by the two matching components. Experimental results are given for matching a database of 200 3D face models with 598 2.5D independent test scans acquired under different pose and some lighting and expression changes. These results show the feasibility of the proposed matching scheme.
23366254
Autonomous Information Services Integration for High-Assurance in Demand-Oriented Information Systems
With interdependent requests of multi-service increasing, the need for adaptability, timeliness and reliability to information service systems has become more and more important. In this paper, the relationship between the timeliness and the reliability of correlated services allocation and access is clarified. Based on these factors, the autonomous network-based information services integration technology to provide one-stop service for users’ multi-service requests is proposed. We proved the effectiveness of the proposed technology through the simulation and the results show that the integrated service can reduce the total users access time compared with the conventional systems.
12662382
Autonomous rating oriented agent allocation to achieve high response in demand-oriented information service system
The efficient and reliable information service provision and utilization is an important infrastructure in the high-assurance information service system. In this paper, we introduce a rating oriented distributed information system sustained by push/pull mobile agents to cope with providers' and users' heterogeneous requirements. Based on this environment, autonomous information provision technology is proposed. However, when users' demand changes, congestion might arise in the system. In order to achieve load balancing for users' timeliness access and guarantee that users can always get the information from a certain pathway, autonomous information reallocation technology is proposed.
59108819
Agent-Based Rating Oriented Information Provision and Reallocation for High-Assurance in Open and Dynamic Environments
In order to meet the heterogeneous requirementsfrom service providers and users simultaneously, thereis an urgent need for a new information service system.After studying the characteristics of the users' accessing,that popularity of information utilization generallyexists in information system is focused. Thispaper introduces a rating oriented distributed informationsystem sustained by push/pull mobile agents for informationservice provision and utilization. Based onthis environment, autonomous information allocationtechnology is proposed. However, when users' demandchanges, congestion might arise in the system. In orderto achieve load balance for users' timeliness accessand guarantee that users can always get the informationfrom a certain pathway, autonomous informationreallocation technology is proposed. Through the comparisonsimulation to the conventional system, the effectivenessof proposed system is proved.