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Prior work of network coding is mainly focusing on multicast traffic. In this thesis, we propose a new network coding based communication algorithm called Network Coded Flooding (NCF) which is related to network wide broadcast. This designed algorithm is an integration of network coding and one of the commonly used broadcasting techniques in wireless networks. In this thesis, we choose Probabilistic Flooding Algorithm (PFA) to integrate with network coding since it is a simple and robust flooding algorithm; it can be used in random wireless networks; it can work without any network topology information. As with PFA, NCF has a parameter of rebroadcast probability that controls packets’ rebroadcasts when receiving innovative packets. During the process of designing NCF, we also consider the issues how efficient network coding can achieve...
Our society depends more strongly than ever on large networks such as transportation networks, the Internet and power grids. Engineers are confronted with fundamental questions such as “how to evaluate the robustness of networks for a given service?”, “how to design a robust network?”, because networks always affect the functioning of a service. Robustness is an important issue for many complex networks, on which various dynamic processes or services take place. In this work, we define robustness as follows: a network is more robust if the service on the network performs better, where performance of the service is assessed when the network is either (a) in a conventional state or (b) under perturbations, e.g. failures, virus spreadings etc. In this thesis, we survey a particular line of network robustness research within our general fr...
Oil resources are unevenly distributed on the earth and most oil needs to be transported by sea. Therefore, ocean transport of oil is largely a one-way trade from the principal supply areas to the oil consuming states. The main routes of crude oil shipping are from the Middle East and Southeast Asia to the United States, Western Europe, Japan and China. It is often on these busy routes that the oil pollution incidents occur. Since the Second World War, oil has become the main source of energy in the world. Oil movements by sea increased since then, more and larger tankers were built to satisfy the increasing need for oil consumption. Hence, the problem of marine oil pollution increased with the growth of carriage of oil by sea.
Resource conservation, Anadromous species, Fishery management, Life history, Population dynamics, Rare species, China, People's Rep., Tenualosa reevesii
Nonlinear compensation of a second and third order system with dry friction
Array architectures based on the VLSI technology allow the processing speed to increase by several orders of magnitude. While VLSI holds the promise of high parallelism by offering almost unlimited hardware at very low cost, there are several inherent constraints with respect to communication, design complexity, testability, etc. In this paper, we are concerned with design and testing of such an architecture. An array- processor chip consisting of 8x8 processing elements (PEs) each with 512 bits of memory was fully designed and fabricated using 2m CMOS technology. One of the novel features of this design is the capability to load data fast into all the PEs simultaneously. Extensive simulations were carried out on this design. This general purpose parallel processor chip was tested using the test workstation IMS-VS2000. An application b...
G protein coupled receptor kinases (GRKs) regulate the termination of G protein-coupled receptor (GPCR) activation by phosphorylating agonist-occupied GPCRs. Apart from terminating GPCR activation, more evidence emerges in recent years demonstrating that GRKs also interact with multiple intracellular signaling molecules, suggesting novel regulatory roles of GRKs. GRK2 has first been identified as a β-adrenergic receptor kinase (βARK). As the most studied member of GRK family, GRK2 is particularly highly expressed in immune and nervous system and is involved in many disease processes. Our previous work indicated that a reduced intracellular GRK2 protein level is related to prolonged inflammatory pain. In this thesis, we further investigated how GRK2 regulates the duration and severity of inflammatory pain. We focussed on: 1. the role o...
This dissertation addresses issues in the control of nonlinear instabilities in high performance engineering systems. Specifically, we consider nonlinear control systems near the limits of their operating envelope. These are highly nonlinear situations occurring in the high-performance operation of a wide variety of systems. Such systems tend to exhibit nonlinear stabilities in terms of a jump to a new low-performance operating point, oscillatory behavior, chaotic behavior or system collapse in the absence of appropriate control action. Such situations necessitate the study of controlling nonlinear phenomena such as bifurcations and chaos.

A new approach to the control of chaotic dynamical systems is introduced, namely control of routes to chaos. The theme is to design feedback control laws which ensure a sufficient degree of stabili...

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