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Model based predictive control (MPC) is well established and has gained widespread acceptance in the industry and the academic community. The success of earlier industrial heuristic MPC algorithms motivated the research community to develop several algorithms with improved performance and enlarge the region of attraction. All proposed algorithms to some extent form a trade off between a region of attraction, performance and inexpensive optimisation. This thesis makes contributions in the area of MPC algorithm design and in particular examines to what extent different methods for parameterising the degrees of freedom within the input trajectories can improve aspects of the region of attraction, performance and inexpensive optimisation. Kautz functions are explored to parameterise the input sequences in optimal model predictive control (OMPC). It is shown that this modification gives mechanisms to achieve low computational burden with enlarged region of attraction and without too much detriment to performance. The proposed algorithm based on Kautz function parameterisation guarantees stability and recursive feasibility. It is further explored and a general class of function parameterisation is proposed using higher order orthonormal basis functions. A generalised function based MPC algorithm is formulated with guaranteed convergence and recursive feasibility. The efficacy of the proposed parameterisations within existing MPC algorithms are demonstrated by examples. The general class of function parameterisation is further explored by looking at systematic choices for a particular problem. Systematic mechanisms are discussed to choose the best tuned alternative parameterisation dynamics. The numerical examples demonstrate the efficacy of the systematic mechanisms. It is also shown that generalised function parameterisations are computationally efficient when used to achieve an approximately global region of attraction as compared with OMPC, there is a reduction in number of inequalities to represent the region of attraction, the number of multiparametric solutions (and therefore computational complexity and memory storage) and also the computational time using active set methods. Another avenue explored is the efficacy of generalised function parameterisation of the degree of freedom within a robust MPC algorithm. It extends the work of nominal case to the robust scenario and shows that similar benefits accrue. An algorithm is proposed for the robust MPC using the generalised function parameterisation that enables the use of robust control invariant set to enlarge the region of attraction. Finally, the parameterised solution extends to triple mode approaches to simplify the offline computations. In triple mode MPC algorithms, the first novelty is to propose explicit choices of middle mode using generalised function dynamics as a pragmatic choice without demanding offline computations. The second novel contribution is to parameterise the input sequences for both explicit and implicit choices of the middle mode within triple mode MPC algorithms. The improvements, with respect to existing algorithms, are demonstrated by examples.

Development of Wireless Sensor Nodes revolutionaries sensing and control application. The size of sensor node makes it ideal to be used in variety of applications, but this brings more challenges and problems especially as the capacity of onboard battery is limited. It is due to the very reason that initial research in the field of WSN especially on MAC targets mainly on the energy conservation and gives secondary importance towards other attributes of MAC protocols. These attributes includes latency, throughput, fairness and collision. This research keeping in view of current application requirements which demands QoS as well as energy conservation in static and mobile sensor networks proposes MAC protocols to meet these challenges. In this research to improve the efficiency of the collision resolution algorithms used in mainly contention based MAC protocols, an Improved Binary Exponential Backoff Algorithm is proposed. The main target of this protocol is to resolve the problem of access collision by employing interim backoff period. The protocol targets to improve upon the performance of conventional Binary Exponential Backoff Algorithm which suffers heavily from collision. The result shows significant reduction in collision which increases the efficiency of the network in terms of QoS and energy conservation. To eliminate the problem of collision which is one of the major sources of network performance degradation a novel Delay Controlled Collision Free contention based MAC is designed. The protocol uses novel delay allocation technique. DCCF also provides mechanism to achieve fairness among the nodes. Detailed analysis and comparative result shows substantial increase in throughput and decrease in latency as compared to Industrial standard of IEEE 802.15.4 CSMA/CA MAC. The research also proposed novel MAC protocols for mobile sensor networks. These protocols uses a methodology which is based upon signal strength of the beacon sent to the node from various neighbouring coordinators that enable the nodes to seamlessly enter from one cluster to another without any link loss and unnecessary delays in the shape of association. The proposed scheme is implemented over IEEE 802.15.4 enabling the standard to perform better with dynamic topology. Result shows that mobility adaptive 802.15.4 protocol shows improvement in QoS and conserve energy far better than the existing conventional CSMA/CA MAC standard. Also the algorithm is implemented over Delay Controlled Collision Free Mac protocol and a detail comparison is carried out with other mobility adaptive MAC protocols. The result shows significant decrease in latency as well as high gain in throughput and considerable reduction in energy as compared to the mobility adaptive MAC protocols. Finally in order to resolve fundamental problem of scalable network which suffers from bottleneck as more nodes in the last hop tries to send data towards the sink, a novel protocol is proposed which allows more than one node at a time to transmit the data towards the sink. The protocol named Simultaneous Multi node CSMA/CA enables the conventional industrial standard of IEEE 802.15.4 CSMA/CA protocol to allow more than one node to transmit the data towards the coordinator or sink node. The protocol out performs the existing standard and provides significant increase in QoS of the network.

Traditionally, scholars have held that in Plato's Phaedo, Forms are said to not be 'in' sensible particulars. The entities that are said to be in sensible particulars are immanent characters. Gail Fine tries to flip this narrative but does not succeed. Daniel T. Devereux attempts to show this by arguing that entities such as hotness in fire perish. I contend that Devereux's argument is not enough to establish that such entities are not Forms. They are not Forms because either they are said to withdraw, and withdrawal is a genuine, non-Cambridge change. Forms cannot undergo a non-Cambridge change, so these entities cannot be Forms. Or, they are said to perish, and perishing is a change that matters, since Forms are not made up of parts. Forms cannot undergo changes that matter, so these entities cannot be Forms.