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Subsynchronous resonance (SSR) is one of the major obstacles for the wide spread of high degrees (60% and higher) of series capacitor compensation. Recently, a new obstacle, namely Subsynchronous Interaction (SSI) has been added to the list after the Zorillo Gulf wind farm incident in Texas in October 2009. SSI is due to the interaction between large Doubly Fed Induction Generator (DFIG)-based wind farms and series capacitor compensated transmission systems. In integrated power systems incorporating series capacitor compensated transmission lines and high penetration of wind energy conversion systems, especially DFIG-based wind farms, SSR and SSI could occur concurrently as a result of some system contingences. Therefore, mitigating SSR and SSI is an important area of research and development targeting at developing practical and effective countermeasures. This thesis reports the results of digital time-domain simulation studies that are carried out to investigate the potential use of offshore and DFIG-based wind farms for simultaneous mitigation of SSR and SSI. This is achieved through introducing supplemental control signals in the reactive power control loops of the grid side converters of the DFIG wind turbines or the HVDC onshore Modular Multilevel Converter (MMC) connecting the offshore wind farm to the grid. In this context, two supplemental controls designated as Supplemental Controls I and II are examined. Supplemental Control I introduces a signal in the HVDC onshore converter to damp both SSR and SSI oscillations. On the other hand, Supplemental Control II introduces a signal in the HVDC onshore converter for damping SSR oscillations and another signal in the grid side converters of the DFIG wind turbines for damping SSI oscillations. Time-domain simulations are conducted on a benchmark model using the ElectroMagnetic Transients program (EMTP-RV). The results of the investigations have demonstrated that the presented two supplemental controls are very effective in mitigating the SSR and SSI phenomena at different system contingencies and operating conditions.

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The intensity of negotiations, including war and Peace Talks, are driven by the threat of identity disintegration. Sri Lanka negotiates to preserve territorial integrity. Tamils argue for secession to preserve their identity. How is each to adapt their identity so that they can peacefully co-exist within the island? The current peace process began in 2002. The principles of Organizational Cybernetics show distinction is warranted between External Self-Determination (secession) and Internal Self-Determination (a single sovereignty recognised by the international community) as the negotiating systems occupy different recursive positions relative to each other. In each context, the systems gravitate differently towards cohesion and autonomy. Equally vital is to distinguish between systems, their embedments and their representatives. Diagnosis of the peace process seeking an internal self-determination solution does not display these distinctions. At the 2002 Peace Talks the only system permitted to negotiate with Sri Lanka (the encompassing system) was confined to one of the embedded systems (the Tamils as represented by the LTTE). Structurally this risked the encompassing system collapsing to represent its missing embedded systems. To rectify this Team Syntegrity is proposed, whose sequence of design in its multiple cascades enables representation issues to be resolved without it being confined to political parties. Content solutions are matters for Sri Lankans to design. However, they are considered in order to design and propose a ‘process’ solution. The journey this thesis takes is to arrive at designing the ‘how’ of negotiations so that it can accommodate the myriad of ‘what’ needs to be negotiated. A meta-level logic is required to resolve the undecidable proposition of preserving territorial integrity or secession. Working with the levels of recursion - the UN, the State and its embedded systems, this thesis proposes a way to absorb residual variety to gain agreement to negotiate internal self-determination based on interlocking negotiations involving those seeking cohesion and those seeking autonomy. This process also opens the way to address the solution design of the other interacting crises afflicting Sri Lanka. The uniqueness and contribution of this research is that it is the first time Organizational Cybernetics has been conceptually applied to diagnose and design a peace process involving a sovereign State.

Culture shapes most human behaviour, including interaction with computers. In much Human-Computer Interaction (HCI) research, culture is assumed to impact design preferences. However, many cultural variables identified in the general literature have no clear link to design preferences. In this thesis, we develop a new model, the Diamond Model, to structure a wide range of cultural variables. This is used to organise a literature review of cultural variables and their impact in HCI, as well as to identify instances of Jordanian cultural variables, which is the focus of field studies in this thesis. The balance and range of cultural variables in the Diamond Model suggests that culture should have impact beyond design preferences, and should also influence how users react to, explain and evaluate difficulties when using computers. To investigate whether this was the case, a series of field studies was carried out to explore the balance between the impact of culture on design preferences and on reactions to usage difficulties. Each field study found Jordanian instances for cultural variables in the Diamond Model, but also added further cultural variables that had not been identified in either the general or the HCI literature. In the process, we identified more cultural variables that influenced reactions to usage difficulties in Jordan than influenced design preferences. This thesis presents the Diamond Model, applies it to existing literature on culture and HCI, and uses it to structure analysis of results from three field studies. The result is an extended Diamond Model with specific Jordanian instances of cultural variables. However, this alone may not help software developers to understand how culture impacts HCI in Jordan. To complement the Diamond Model, we developed a novel approach called “Dramatic Sketches” to communicate impact of cultural variables on HCI. We present example Dramatic sketches and conclude with guidance on developing software for Jordanian contexts.

The continuous growth of the gaming industry develops a highly competitive environment, which provides an incubator of innovation. These conditions lead to the emergence of new business models. Free to play as one of those newly and still developing models is currently trending among the game developing and publishing companies. Delivering skyrocketing profits, the full potential of the model is yet to be revealed. At first sight, the model has a simplistic structure on the business side, however, on the user side it is unclear what motivates players to become customers through the purchase of digital items in the games. This research uses an exploratory and qualitative approach to collect data and identify purchasing behaviour stimuli. It also proposes an option of connecting personality theories as a possible explanation to the purchasing behaviour of players. As a focus for this study, the currently most successful free to play game, League of Legends, was selected and twelve interviews with League of Legends players were conducted. The interviews consisted of two parts, one semi-structured and the other one structured. The semi-structured interview aimed at identifying purchasing behaviour and finding reasons for the purchase of digital items in League of Legends. The second was a personality assessment test, Keirsey Temperament Sorter2. A conventional content analysis of the interviews identified the theme “personal satisfaction” as the main motivation for purchasing digital items. The investigation regarding the proposed connection to personality theory, the research’s results fail to show any connection. However, answering research question number one unveils the importance of the personality factor remains valid and a subject of future research. The research discusses possibilities and direction for future research in the face of testing other than the applied Keirsey personality theory.