Abstract
In the last few years, information outsourcing has been a current activity on large companies. Information as become a regular trading commodity. It is a well known fact that direct mailing companies acquire databases, or other kind of information sources, from other companies with names and addresses of potential clients. Also, enterprise managers are frequently concerned with the current status and welfare of their clients and suppliers. Commonly, they use to appeal to specialized external information providers which may, under certain conditions, provide them specific profiles about such potential commercial partners. On companies with effective means of information processing, it is very probable that such needs of information may be directly satisfied with data stored and managed in the companies' data warehouses. In this paper we propose a protocol based on economic principles that enables the automatic negotiation of information transference between data warehouse systems of different companies. The protocol was designed to be used by a community of intelligent agents responsible to ensure and support all the operational tasks related to information outsourcing among companies.

Abstract

Abstract
In this work we investigate how different machine settings for a hardware Distributed Shared Memory (DSM) architecture affect the performance of parallel logic programming (PLP) systems. We use execution-driven simulation of a DASH-like multiprocessor to study the impact of the cache block size, the cache size, the network bandwidth, the write buffer size, and the coherence protocol on the performance of Andorra-I, a PLP system capable of exploiting implicit parallelism in Prolog programs. Among several other observations, we find that PLP systems favour small cache blocks regardless of the coherence protocol, while they favour large cache sizes only in the case of invalidate-based coherence. We conclude that the cache block size, the cache size, the network bandwidth, and the coherence protocol have a significant impact on the performance, while the size of the write buffer is somewhat irrelevant.

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Abstract
We consider the performance of a hybrid radio-over-fiber distribution system with a remote phase-locked loop (PLL) providing the local oscillator for upconversion to millimeter (mm)-wave frequencies. The reference signal for the PLL is transmitted together with digitally modulated subcarriers over a fiber link, allowing centralization of radio processing. Through analysis and simulation, we identify the relationship between the phase noise requirement for the PLL and the data capacity of the fiber link. For a practical link, we provide an upper limit on system capacity for transmission of 16 quadrature amplitude modulation (QAM) subcarriers.

Abstract
In this paper, we analyze the ability of the P-NET fieldbus network to cope with the timing requirements of a Distributed Computer Control System (DCCS), where messages associated to discrete events should be made available to a distributed application within a maximum bound time. The major contribution of this paper is the integration of a pre-run-time schedulability analysis of the P-NET protocol with the typical Distributed Computer Controlled System requirements. A case study of a petrochemical DCCS application and its message communication support is presented, stressing some of the timing requirements that must be satisfied by the message exchanges. An implementation supported by a P-NET fieldbus network is then analyzed and some conclusions are drawn about this example.