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This paper presents the concept and theoretical specification of a multi-agent based model for spatio-temporal simulation of a coupled human–landscape system. The model falls into the class of all agents, where the human population and the landscape environment are all self-organized interactive agents. The model framework is represented by four components: (i) a system of human population defining specific behavioural patterns of farm households in land-use decision-making according to typological livelihood groups, (ii) a system of landscape environment characterising individual land patches with multiple attributes, representing the dynamics of crop and forest yields as well as land-use/cover transitions in response to household behaviour and natural constraints, (iii) a set of policy factors that are important for land-use choices, and (iv) a decision-making procedure integrating household, environmental and policy information into land-use decisions of household agents. In the model, the bounded-rational approach, based on utility maximisation using spatial multi-nominal logistic functions, is nested with heuristic rule-based techniques to represent decision-making mechanisms of households regarding land use. Empirical verifications of the model's components and the application of the model to a watershed in Vietnam for integrated assessments of policy impacts on landscape and community dynamics are subjects of a companion paper.

An IP mobility support protocol that enables personal and terminal mobility for IP-based applications is put forward. This protocol does not require new network entities or support from network service providers. It comprises an innovative IP-to-IP address mapping module at the network layer and an user agent to interact with a directory service server and correspondent nodes. It does not require a permanent IP address and a home server. It does not use tunnelling on mobile nodes nor alter route path of IP packets. In this paper, we describe our implementation and present our experimental results. Experiments show that this protocol works for UDP and TCP connections without affecting the throughput of the mobile node on a wireless LAN. Related works are also discussed and quantitatively compared. As an example, this protocol provides seamless execution for applications like VoIP and video conferencing on mobile nodes that roam across wireless networks.

High-field superconducting solenoids have proven themselves to be of great value to scientific research in a number of fields, including chemistry, physics and biology. Present-day magnets take advantage of the high-field properties of Nb3Sn, but the high-field limits of this conductor are nearly reached and so a new conductor and magnet technology is necessary for superconducting magnets beyond 25 T. Twenty years after the initial discovery of superconductivity at high temperatures in complex oxides, a number of high temperature superconductor (HTS) based conductors are available in sufficient lengths to develop high-field superconducting magnets. In this paper, present day HTS conductor and magnet technologies are discussed. HTS conductors have demonstrated the ability to carry very large critical current densities at magnetic fields of 45 T, and two insert coil demonstrations have surpassed the 25 T barrier. There are, however, many challenges to the implementation of HTS conductors in high-field magnets, including coil manufacturing, electromechanical behavior and quench protection. These issues are discussed and a view to the future is provided.