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Wireless sensor networks (WSN) are widely used in various situations. Energy saving is one of the most important issues because of the limited power. Communication is the mainly energy consuming part of sensor nodes. Reducing the size of transmitted data can conserve the energy of nodes. Spatial and temporal correlation is ubiquitous in wireless sensor networks. By exploiting spatial and temporal correlation, only a subset of data need to be transmitted and the rest of the data can be estimated. Data aware clustering is an effective way to exploit spatial correlation among sensor nodes. In our SC-EEDC framework, fuzzy ART artificial neural network is used to measure the shape similarity among data sequences and the magnitude similarity is estimated by a magnitude similarity model. And two corresponding estimation algorithm are proposed. We propose Weighting based K-means clustering algorithm (WK-means), which considers multiple clustering factors in addition to the data similarity. The K-means algorithm structure is introduced in clustering algorithm to search the more energy-saving clustering topology. Anchor node based data collection strategy is proposed to measure the spatial correlation in real time and suppress the transmission of spatial redundant data at source node. Sleeping scheduling is introduced to dynamically adjust the spatial sampling rate and the temporal redundancy is reduced using Length Encoding. The cluster maintenance scheme keeps the cluster structure’s efficiency over the network lifetime. Simulation results show that our SC-EEDC achieves significant data reduction without affecting the accuracy of collected data, reduces the energy consumption in each round of data collection and effectively prolongs the network lifetime.

An extended seal calculus language, ExtSealL, and its syntax is introduced in this paper. A frame structure is proposed for ExtSeal. A construction method for translating a seal definition into the frame definition is proposed and a transformation function is given based on the method. An operating semantics is developed basing on the frame structure, an example of a frame and its execution are given.

For MPLS VPN (Multi-Protocol Label Switching Virtual Private Network) not suitable for the complex business logic and application with high security requirements because of its lack of providing encryption and certification, a scheme of enhancing MPLS VPN QoS is proposed. It uses the method based on "Log-infinitely Divisible Cascades", realizes fine-grained security service strategy by integrating VPN and IPsec (IP security) and using cryptographies such as encrypted authentication, etc. Simulation results show that the proposed scheme increases the safety factor to clients and ensure the need for QoS of the application of high-end users.

As a distributed process calculus with localities and mobility of computational entities, Seal calculus is playing an important role in expressing key features such as security and mobility of Internet programming directly. However, little implementation technique proposed for the calculus, partly due to the complication of mobile computation, which fusions three important techniques: concurrency, distribution and mobility at the same time. The abstract machine PSN for a distributed implementation of the Seal calculus is presented. In PSN the logical structure of a seal system and its physical distribution are separated which induces a more simple and clear implementation. Moreover, an operational semantics description of the Seat calculus based on PSN is given.

The Seal calculus is a calculus of mobile computations designed for programming secure distributed applications over large scale open networks such as the Internet. This paper presents a distributed implementation for the Seal calculus based on an abstract machine SAM, a translation from Seal terms to SAM term, a proof of the correctness of such a translation, which asserts that a Seal term and its translation exhibit the same observance behavior, and a prototype Java implementation. The implementation helps to speed up the development of programming languages based on Seal and experimentation of Seal on concrete examples.