Mobile businessprocess modelingusinghigh level Petri nets

This paper aims at providing an effective modeling methods for more and more mobile business applications. First a high level Petri nets method-Xml nets is introduced, which combines the advantage of Petri nets and XML. Petri nets have strict mathematics and intuitionistic diagram ex- pression way, rich system describing means and system behavior analytical technology, and the re- lated powerful supporting tools. XML, as an extensible markup language, is already a information description de facto standard. XML nets could be utilized to model both the controlling flow and the data flow of mobile business process effectively, which consequently enables the analysis and optimi- zation of the mobile business processes and could be utilized to simulate the execution of the mobile business process with the Petri nets tools to improve the system execution efficiency. In this paper, to demonstrate the modeling of the controlling flow and data flow of mobile business process, an in- strument repair business case is modeled with XML nets.

Barbed congruence of the asymmetric chi calculus

The ehi calculus is a model of mobile processes. It has evolved from the pi-calculus with motivations from simplification aml communication-as-cut-eliminatinn. This paper studies the ehi calculus in the framework incorporating asymmetric communication. The major feature of the calculus is the identification of two actions： x/x and τ. The investigalion on the barbed bisimilarity shows how the property affects the observational theory. Based on the definition of the barbed bisimilarity, the simulation properties of the barbed bisimilarity are studied. It shows that the algebraic properties of the barbed bisimiilarity have changed greatly compared with the chi calculus.Although the definition of the barbed bisimilarity is very simple, the properly of closeness under contexts makes it difficuh to understand the barbed bisimilarity directly. Therefore an open style definition of the barbed bisimilarity is given, which is a context free description of barbed bisimilarity. Its definition is complex, but it is a well-behaved relation for it coincides with the barbed bisimilarity. It also helps to build an axiomatization system for the bathed congruence. Besides the axioms for the strong barbed bisimilarity, the paper proposes a new tau law and four new update laws for the barbed congruence. Both the operational and algebraic properties of the enriched calculus improve the understanding of the bisimulation behaviors of the model.

A predicate spatial logic for mobile processes

A modal logic for describing temporal as well as spatial properties of mobileprocesses, expressed in the asynchronous π-calculus, is presented. The logic has recur-sive constructs built upon predicate-variables. The semantics of the logic is establishedand shown to be monotonic, thus guarantees the existence of fixpoints. An algorithm isdeveloped to automatically check if a mobile process has properties described as formulasin the logic. The correctness of the algorithm is proved.

Computing Bisimulations for Finite-Controlπ-Calculus

Symbolic bisimulation avoids the infinite branching problem causedby instantiating input names with all names in the standard definition of bisimulation in л-calculus. However, it does not automatically lead to an efficient algorithm,because symbolic bisimulation is indexed by conditions on names,and directly manipulating such conditions can be computationally costly. In this paper a new notionof bisimulation is introduced, in which the manipulation of maximally consistent conditions is replaced with a systematic employment of schematic names. It is shownthat the new notion captures symbolic bisimulation in a precise sense. Based on thenew definition an efficient algorithm, which instantiates input names 'on-the-fly', ispresented to check bisimulations for finite-control л-calculus.

Visual Person Identification Using a Distance-dependent Appearance Model for a Person Following Robot

This paper describes a person identifcation method for a mobile robot which performs specifc person following under dynamic complicated environments like a school canteen where many persons exist.We propose a distance-dependent appearance model which is based on scale-invariant feature transform（SIFT） feature.SIFT is a powerful image feature that is invariant to scale and rotation in the image plane and also robust to changes of lighting condition.However,the feature is weak against afne transformations and the identifcation power will thus be degraded when the pose of a person changes largely.We therefore use a set of images taken from various directions to cope with pose changes.Moreover,the number of SIFT feature matches between the model and an input image will decrease as the person becomes farther away from the camera.Therefore,we also use a distance-dependent threshold.The person following experiment was conducted using an actual mobile robot,and the quality assessment of person identifcation was performed.

CELP-Based Implementation of the GSM Half-Rate Speech Codes

This paper presents the real-time implementation of 6.75kb/s speech codec for the GSM half-rate digital cellular system based on CELP[1]. Logarithmic Area Ratio (LAN).[2] quanrizarion for short term Parameters and eeeicient adaptive codebook search are used. An overlapping center-clipping codebook and the fonnufor for fast searching are proposed. The MOS of the synthesized speech is over 3.5.