5921528
PRISMATICA: toward ambient intelligence in public transport environments
On-line surveillance to improve safety and security is a major requirement for the management of public transport networks and other public places. The surveillance task is a complex one involving people, management procedures, and technology. This work describes an architecture that takes into account the distributed nature of the detection processes and the need to allow for different types of devices and actuators. This was part of a major European initiative on intelligent transport systems. Because of the dominant nature of closed circuit television in surveillance, This work describes in detail a computer-vision module used in the system and its particular ability to detect situations of interest in busy conditions. The system components have been implemented, integrated, and tested in real metropolitan railway environments and are considered to be the first step toward providing ambient intelligence in such complex scenarios. Results are presented that not only deal with detection performance, but also on the perception of people who used the system on its effectiveness and potential impact.
1433509
A Distributed Surveillance System to Improve Personal Security in Public Transport
This paper presents a distributed surveillance system to improve safety andsecurity in public transport environments such as metropolitan railways,airports etc. The system is constructed by a set of modules that provideadditional intelligence to detect potentially dangerous situations and providemore timely prevention and management of events. These modules includeCCTV video processing, audio detection, mobile smart cards, a range of otherpossible sensors and a supervisory front-end. The system design uses ideasfrom control engineering and distributed network communication resulting in aCORBA based architecture and XML messaging. The system components havebeen implemented and integrated in two major successful trials in metropolitanrailway stations (London and Paris) and at Newcastle International Airport, aspart of a major EU-funded project PRISMATICA (?PRo-active Integratedsystems for Security Management by Technological, Institutional andCommunication Assistance?).
21826244
Fault-tolerant grid architecture and practice
Grid computing emerges as effective technologies to couple geographically distributed resources and solve large-scale computational problems in wide area networks. The fault tolerance is a significant and complex issue in grid computing systems. Various techniques have been investigated to detect and correct faults in distributed computing systems. Unreliable fault detection is one of the most effective techniques. Globus as a grid middleware manages resources in a wide area network. The Globus fault detection service uses the well-known techniques based on unreliable fault detectors to detect and report component failures. However, more powerful techniques are required to detect and correct both system-level and application-level faults in a grid system, and a convenient toolkit is also needed to maintain the consistency in the grid. A fault-tolerant grid platform (FTGP) based on an unreliable fault detector and the Globus fault detection service is presented in this paper. The platform offers effective strategies in such three aspects as grid key components, user tasks, and high-level applications.
36798999
Stereo Matching Using Belief Propagation
In this paper, we formulate the stereo matching problem as a Markov network and solve it using Bayesian belief propagation. The stereo Markov network consists of three coupled Markov random fields that model the following: a smooth field for depth/disparity, a line process for depth discontinuity, and a binary process for occlusion. After eliminating the line process and the binary process by introducing two robust functions, we apply the belief propagation algorithm to obtain the maximum a posteriori (MAP) estimation in the Markov network. Other low-level visual cues (e.g., image segmentation) can also be easily incorporated in our stereo model to obtain better stereo results. Experiments demonstrate that our methods are comparable to the state-of-the-art stereo algorithms for many test cases.
62600747
Automatic cascade training with perturbation bias
Face detection methods based on cascade architecture have demonstrated fast and robust performance. Cascade learning is aided by the modularity of the architecture in which nodes are chained together to form a cascade. In this paper we present two new cascade learning results which address the decoupled nature of the cascade learning task. First, we introduce a cascade indifference curve framework, which connects the learning objectives for a node to the overall cascade performance. We derive a new cost function for node learning, which yields fully-automatic stopping conditions and improved detection performance. Second, we introduce the concept of perturbation bias, which leverages the statistical differences between target and non-target classes in a detection problem to obtain improved performance and robustness. We derive necessary and sufficient conditions for the success of the method and present experimental results.
2683442
Extracting FSMs from Object-Z specifications with history invariants
Object-Z with history invariants can present precise and abstract models for complex systems. The system behavior patterns are often implicitly embedded within various state/operational constraints and history invariants. Without explicit system behavior representations, it is difficult to implement those abstract models. In this paper, we present a sound and systematic approach to automatically extract explicit system behaviors (as FSMs) from the abstract Object-Z specifications. Safety and liveness and additional crucial requirements for open systems are ensured.
14529794
Research into Verifying Semistructured Data
Semistructured data is now widely used in both web applications and database systems. Much of the research into this area defines algorithms that transform the data and schema, such as data integration, change management, view definition, and data normalization. While some researchers have defined a formalism for the work they have undertaken, there is no widely accepted formalism that can be used for the comparison of algorithms within these areas. The requirements of a formalism that would be helpful in these situations are that it must capture all the necessary semantics required to model the algorithms, it should not be too complex and it should be easy to use. This paper describes a first step in defining such a formalism. We have modelled the semantics expressed in the ORA-SS (Object Relationship Attribute data model for SemiStructured data) data modelling notation in two formal languages that have automatic verification tools. We compare the two models and present the findings.