MOBILITY SUPPORT ARCHITECTURES FOR NEXT-GENERATION WIRELESS NETWORKS

With the convergence of the wireless networks and the Internet and the booming demand for multimedia applications, the next-generation (beyond the third generation, or B3G) wireless systems are expected to be all IP-based and provide real-time and non-real-time mobile services anywhere and anytime. Powerful and efficient mobility support is thus the key enabler to fulfil such an attractive vision by supporting various mobility scenarios. This thesis contributes to this interesting while challenging topic. After a literature review on mobility support architectures and protocols, the thesis starts presenting our contributions with a generic multi-layer mobility support framework, which provides a general approach to meet the challenges of handling comprehensive mobility issues. The cross-layer design methodology is introduced to coordinate the protocol layers for optimised system design. Particularly, a flexible and efficient cross-layer signalling scheme is proposed for interlayer interactions. The proposed generic framework is then narrowed down with several fundamental building blocks identified to be focused on as follows. As widely adopted, we assume that the IP-based access networks are organised into administrative domains, which are inter-connected through a global IP-based wired core network. For a mobile user who roams from one domain to another, macro (inter-domain) mobility management should be in place for global location tracking and effective handoff support for both real-time and non-real-lime applications. Mobile IP (MIP) and the Session Initiation Protocol (SIP) are being adopted as the two dominant standard-based macro-mobility architectures, each of which has mobility entities and messages in its own right. The work explores the joint optimisations and interactions of MIP and SIP when utilising the complementary power of both protocols. Two distinctive integrated MIP-SIP architectures are designed and evaluated, compared with their hybrid alternatives and other approaches. The overall analytical and simulation results shown significant performance improvements in terms of cost-efficiency, among other metrics. Subsequently, for the micro (intra-domain) mobility scenario where a mobile user moves across IP subnets within a domain, a micro mobility management architecture is needed to support fast handoffs and constrain signalling messaging loads incurred by intra-domain movements within the domain. The Hierarchical MIPv6 (HMIPv6) and the Fast Handovers for MIPv6 (FMIPv6) protocols are selected to fulfil the design requirements. The work proposes enhancements to these protocols and combines them in an optimised way. resulting in notably improved performances in contrast to a number of alternative approaches

Studies of oxide/ZnO near-interfacial defects by photoluminescence and deep level transient spectroscopy

The evolution of near-interfacial defects from Al2 O3 ZnO and MgOZnO upon thermal annealing has been studied by photoluminescence, deep level transient spectroscopy, and secondary ion mass spectroscopy. We find that all the results are strongly connected and that they point to the direction that Zn outdiffuses from ZnO to the oxide layer during annealing and creates deep level defects near the interfacial region. These defects reduce the band-edge emission and increase the deep level emission at 2.37 eV. Our study shows that the oxide/ZnO interface is relatively fragile and caution must be taken for making metal-oxide-ZnO based transistors and light emitting diodes. © 2008 American Institute of Physics.published_or_final_versio

Ethnic differences in susceptibilities to A(H1N1) flu: An epidemic parameter indicating a weak viral virulence

The current A(H1N1) flu has showed sub-population dependent susceptibility and fatality as early as April and May of 2009 in its first wave of spreading. After the pandemic outbreak spreads globally for more than seven months, the subpopulation dependence of this flu, including ethnicity, age and genderselectivity, has been recognized by several research groups. This paper attempts to discussed how to identify ethnic selectivity from the released data by WHO relevant to this ongoing flu, review some recently published papers describing the presence of ethnic differences in susceptibilities to the H1N1flu virus and further raised an argument that ethnic differences in  susceptibilities to a virus might be a piece of evidence reflecting a weak virulence of that specific virus

A Novel Framework for Backstepping-Based Control of Discrete-Time Strict-Feedback Nonlinear Systems with Multiplicative Noises

10.13039/501100001809-National Natural Science Foundation of China (Grant Number: 61773169, 61873058, 61873148, 61933007 and 61973129); 10.13039/501100003453-Natural Science Foundation of Guangdong Province (Grant Number: 2019B151502058); Fundamental Research for the Central Universities of China; 10.13039/501100000288-Royal Society; Alexander von Humboldt Foundation of Germany

Synchronization Control for a Class of Discrete-Time Dynamical Networks With Packet Dropouts: A Coding-Decoding-Based Approach

10.13039/501100000288-Royal Society; 10.13039/501100001809-National Natural Science Foundation of China; 10.13039/501100000923-Australian Research Council; Program for Capability Construction of Shanghai Provincial Universities; 10.13039/100005156-Alexander von Humboldt-Stiftung

Moving Horizon Estimation of Networked Nonlinear Systems with Random Access Protocol

10.13039/501100001809-National Natural Science Foundation of China (Grant Number: 61873148, 61703245, 61490701 and 61751307); 10.13039/501100010040-Taishan Scholar Project of Shandong Province of China; 10.13039/501100000923-Australian Research Council Discovery Project (Grant Number: DP160103567); 10.13039/100005156-Alexander von Humboldt Foundation of Germany; 10.13039/501100002858-China Post-Doctoral Science Foundation; Post-Doctoral Special Innovation Foundation of Shandong (Grant Number: 201701015); 10.13039/501100000288-Royal Society of the United Kingdom

Probability-Guaranteed Envelope-Constrained Filtering for Nonlinear Systems Subject to Measurement Outliers

10.13039/501100001809-National Natural Science Foundation of China (Grant Number: 61773209, 61873148, 61933007 and 61673141); Australian Research Council Discovery Project (Grant Number: DP160103567); 10.13039/501100004608-Natural Science Foundation of Jiangsu Province (Grant Number: BK20190021); 10.13039/501100010014-Six Talent Peaks Project in Jiangsu Province (Grant Number: XYDXX-033); Alexander von Humboldt Foundation of Germany

Local Stabilization for Multiple Input-Delay Systems subject to Saturating Actuators: The Continuous-time Case

National Natural Science Foundation of China under Grants 61773156, 61873148, and 61933007; Natural Science Foundation of Henan Province of China under Grant 202300410159; Program for Science and Technology Innovation Talents in the Universities of Henan Province of China under Grant 19HASTIT028; Royal Society of the U.K.; Alexander von Humboldt Foundation of Germany