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Granulation is a process of size enlargement of primary particles which aims to improve their properties such as flowability and compressibility. For decades of development, the granulation has been widely used in many industries such as food and pharmaceutical. Melt granulation has received more attention from industries due to its unique advantages in recent years. In this research, the melt granulation experiments were performed on high shear mixer (HSM) and fluidized bed granulator (FBG) to produce granules and then processed into tablets. The experiments were carried out with different combinations of process and formulation variables, such as impeller speed, liquid to solid ratio in HSM; and air velocity and liquid to solid ratio in FBG. The product properties such as granule size, strength, dissolution, and tablet strength, hardness and dissolution were intensively studied, along with the granule and tablet surface studies with scanning electron microscope (SEM). It was found that the properties of HSM granules were mainly determined by the impeller speed, while the air velocity also plays an important role in affecting FBG granule properties. In terms of tablet properties such as strength, porosity and dissolution time, it was noticed that during tabletting, the compression force was the most dominant variable, as the effects of other variables could be minimized when the tablets were compressed with high compression force. After the experimental data was analysed, the data were used to build models to predict both granule (strength, dissolution and porosity) and tablet properties (strength, dissolution, hardness and porosity) of both equipment by design of experiment (DoE) and artificial neural networks (ANN). The input variables for modelling were corresponded to different product properties. Then the predicted values of both models were compared to the actual data, in order to find which model was more suitable to provide accurate predictions. The models will give an opportunity to predict product properties without doing a large number of experiments which saves time.

Concrete filled steel tubular (CFT) columns can employ the advantages of both materials: steel and concrete. Connection to such columns, however, is problematic. This is especially so if the required connection is both bolted and moment-resisting. To address this issue, a novel blind-bolted and moment-resisting connection to CFT column has been developed. This connection uses an innovative blind-bolt, introduced in previous research at the University of Nottingham and is termed the Extended Hollobolt (EHB). The EHB has been developed to provide sufficient tensile resistance and stiffness for the connection to develop resistance to moment. Previous research work has studied the performance of this connection under monotonic loading. The performance of such connection under cyclic loading, however, is not yet investigated. The work presented in this thesis addresses this gap in knowledge. This thesis reports on a series of full scale testing of joints consisting of beam endplates connected to CFT columns using this blind bolt. The test connections were constructed with relatively thick endplate so as to isolate the CFT column and the blind bolt as the relatively weak elements in the connection system. This study focuses on the behaviour of the connections with principal failure modes attributed by the blind bolt and the CFT column. The experiments were conducted to obtain insights into the hysteretic moment-rotation relationship, available ductility & energy dissipation capacity, observe typical failure modes, and develop relevant understandings of the Extended Hollobolt-endplate connection subjected to cyclic loading. The selected connection details were chosen to examine the influential parameters of the joint hysteretic moment-rotation behaviour. From the experimental results, two representative failure modes, bolt fracture and column face bending failure, were observed and categorized in relation to the connection configuration. The connection behaviour are described and compared with respect to the influences of bolt grade, cyclic loading procedure, tube wall thickness and concrete grade. Based on the experimental hysteretic moment-rotation relationships, an evaluation of the cyclic characteristics and an analysis' of the cumulative damage were carried out for the two representative connection categories. The joint hysteretic moment-rotation response was assessed in term of degradations of strength, stiffness, ductility, and energy dissipation. The use of damage levels and stages in the interpretation of damage evolutions for the connection behaviour is also described in this thesis. The findings of cumulative damage analysis suggest that the energy based cumulative damage index outweighs the other indices in characterizing the progressive damage process of the connections in this study. This is especially the case for those related to hysteresis loops at repeated cycles of each loading amplitude. Following the experimental study, 3D nonlinear finite element models of the connections were developed to analyse the mechanical response of the connection. The comparison of the numerical and experimental moment-rotation envelope curve is discussed with respect to related geometric and material parameters. The connection failure modes and displacement distributions were further examined as a supplement to the experimental findings that were necessarily limited by instrumentations. This work also presents mathematical models for the hysteretic moment-rotation relationships simulating the loading, unloading and reloading segments of the hysteresis loops. Characterizing parameters were introduced to, allow for the softening slope, linear segment slope, and degradations of strength and energy dissipation. This study concluded that the proposed finite element model simulates well the behaviour of the connection with good prediction of the moment-rotation envelope curves and of the failure mode. It is also concluded that the proposed mathematical models define well the non-linear loading and unloading paths with reasonable accuracy. It is finally claimed that the Extended-Hollobolt endplate connection provides a stable improvement in strength and stiffness under cyclic loading compared with other similar connections.

This thesis encompasses several critical components: a comprehensive introduction providing an overview of the research, the Course Algorithm developed under Nicholas's guidance, and the IO panel designed. Additionally, it includes the introduction and testing of various electronics, followed by an in-depth discussion of the motor control system optimization, demonstrating work on transmission system optimization. Building upon this optimization, the power system is also optimized to support the sailboat's operation. Moreover, a series of finished testing is included with the resultant analysis. By addressing these key areas, the thesis aims to provide an analysis of the research conducted, highlighting significant contributions to the sailboat's hardware application and component design.

This dissertation analyzes three aspects of the economics of water pollution and is organized in three essays. The first essay examines permit trading in water pollution where pollution is different in the persistence of environmental damage. The second essay examines the problem of reliably meeting a water quality standard under environmental uncertainty. The third essay considers the problem of reliably meeting a water quality standard under asymmetric information. The first essay analyzes how to properly design water pollution permit trading with pollutants which are non-uniformly mixed across space and have different persistence in environmental damages. The efficient solution to water pollution abatement involves integrating the difference in the environmental persistence caused by pollutants and setting trading ratios in permit trading accordingly. The second essay analyzes the problem of meeting a water quality standard with a certain degree of reliability given environmental stochasticity, where the distribution of environmental stochasticity is unknown. The essay develops the use of a reliability target that caps the probability of not attaining the target in any period at α, where 1− α is the level of reliability. A single-tailed version of Chebyshev’s inequality is used that measures the maximum probability of being in the right tail of the probability distribution. The essay also examines a margin of safety in Total Maximum Daily Loads (TMDL) and concludes that if a given level of reliability is desirable, the margin of safety should vary with the level of TMDL. The third essay considers the problem of reliably achieving a water quality standard where water pollution is generated by multiple sources and there is asymmetric information. Asymmetric information comes from privately observable actions like fertilizer application and private information on profits. This essay develops a Vickery-Clark-Groves (VCG) subsidy auction and incorporates a fine/reward scheme based on whether the water quality standard is met. This subsidy auction can achieve an efficient solution to the problem of achieving a reliability standard under asymmetric information.

Abstract: Delay Tolerant Mobile Networks (DTMNs) provide communication despite the occasional presence of disconnected subnetworks. They rely on finding a set of sequential opportunistic encounters between pairs of mobile nodes. In this context, understanding mobile node behaviour is essential to design effective and efficient network protocols. Previous studies aimed to predict future encounters where predictions depend on exploring the probability/age of encounters and integrated interactions in the mobile data. However, those previous solutions suffer from unstable predicted encounters with lack of routing information such as encounter times. As an alternative to prediction, we propose to exploit periodicity within mobile data to find stable (periodic) encounters for routing in DTMNs. In this thesis, we first present a generic methodology to model and find periodic encounter patterns by using the auto-persistence function and detection techniques derived from it. Secondly, we propose a novel graph model to capture periodic encounter patterns where routing problems can be modelled and solved as optimization problems. Lastly, to connect disconnected subnetworks that are strongly connected inside, e.g., by periodic encounters, in the networks we introduce stationary relay nodes whose deployment is modelled as various k-connectivity problems. Taking advantage of our studies, the experimental results demonstrate that in the environment of DTMNs with the presence of disconnected sub-networks, message delivery can benefit greatly from the underlying periodicity within mobile data. In addition, exploiting periodicity opens up new research frontiers in several aspects such as designing novel routing protocols, query dissemination and collection, and preserving privacy and security in environments with the presence of periodic behaviours.

Abstract: In this thesis, we propose a novel approach to detect malicious executables in the network layer using a combination of techniques from bioinformatics, data mining and information retrieval. This approach requires translating malicious code into genome-like representations. Based on their "genetic" formats, we can easily extract features by constructing families for known malicious code using data mining algorithms. These features then can be stored in a router or an another device in the network to measure the similarity between payloads and extracted features. Once the similarity is over a threshold, the security device can block the entire session and report an alert before the threat reaches the intended host(s). Further more, attacks can be identified based on their features and the families where these features come from. Ultimately, our experiments showed that 95% accuracy of detection is possible with an identification rate of 83%.

Integrating an intermittent aeration for the treatment of combined dilute and anaerobic digested swine wastewater in a field swine wastewater treatment system was investigated. Four operations models in term of ratio of aeration to no-aeration of 60:36, 5:1, 4:2 and 3:3 hour were evaluated. At the HRT of 3.2 days and ration of aeration to non-aeration of 3:3, the removal efficiency of BOD5, Total-N, TSS and Total-P of 98.0%, 92.4%, 95.6% and 59.4% could be achieved, respectively. The effluent quality of BOD5, NO3ˉ–N, NH4+–N and TSS concentrations were 35±12mg/l, 2.6±0.8 mg/l, 36±28 mg/l and 78±13 mg/l, respectively. The operational criteria were developed for integrating the intermittent aeration in the swine wastewater treatment system (including anaerobic reactors and sedimentation unit). Economical evaluation of the swine wastewater treatment system integrating the intermittent aeration unit was conducted. It was found that break even point was the operation of 166 pigs if the biogas and stabilized sludge were utilized. If the byproducts were not utilized, the cost of the treatment system are $12.30, $7.92, $7.21, $7.06 and $6.09 for the operation of 300, 1000, 2000, 3000 and 5000 pigs per year, respectively. Integrating the intermittent aeration unit in the swine waste treatment system provides the effective odor control, reduction of energy cost and treated wastewater reuse without creating the deterioration of environmental quality.