Learn More
It is an important problem for pervasive computing to coordinate and compose large numbers of devices and services to achieve users' various task goals. The pervasive computing environment is transparent for users. In order to simplify the interaction between users and the environment, this paper presents a goal-driven approach of service composition. We(More)
Clustering learners into groups according to the customized features in e-learning environment is an important step to build a personalization learning system. Though clustering e-learners is important for better cooperation between teachers and students in e-learning, it is a challenge job to group learners flexibly and exactly. Since there are already(More)
The use of genetic algorithm (GA) to simplify the structures of artificial neural network-based modulation format identification is proposed in next-generation dynamic and heterogeneous fiber-optic networks. Simulation results show that with 80 asynchronous amplitude histogram bins, by virtue of GA, the identification error rate decreases from 4.24 to 1.04(More)
Optical performance monitoring is an important function for high capacity optical transmission system. In this paper, we summarize some of the recent work we have carried out in this area. In particular, PMD independent OSNR monitoring, OSNR monitoring using half symbol delay for SNR monitoring of RZ-DQPSK signal and signed residue dispersion monitoring of(More)
We study long-haul Quasi-Single-mode (QSM) systems in which signals are transmitted in the fundamental modes of a few-mode fiber (FMF) while keeping other system components such as amplifiers and receivers are kept single-moded. The large-effective-area nature of the FMF fundamental modes improves system nonlinear tolerance in the expense of mode coupling(More)
In pervasive computing, the service adaptation means that users can persistently and continuously access services through any mobile device, in any time and in any location. This paper proposes an application layer adaptive framework for services operation of pervasive computing. In this framework, proxy technology and context technology are utilized to(More)
A new scheme of reaction-jet/aerodynamic multi-control missile using pose controlled pulse-engine is present. In this scheme, aerodynamic is used as feedback control, and reaction-jet is feed-forward control. In the first part, the model of the multi-control system is given; then, the aerodynamic controller is designed by using pole assignment, and the(More)