Systematic delay-driven power optimisation and power-driven delay optimisation of combinational circuits

With the proliferation of mobile wireless communication and embedded systems, the energy efficiency becomes a major design constraint. The dissipated energy is often referred as the product of power dissipation and the input-output delay. Most of electronic design automation techniques focus on optimising only one of these parameters either power or delay. Industry standard design flows integrate systematic methods of optimising either area or timing while for power consumption optimisation one often employs heuristics which are characteristic to a specific design. In this work we answer three questions in our quest to provide a systematic approach to joint power and delay Optimisation. The first question of our research is: How to build a design flow which incorporates academic and industry standard design flows for power optimisation? To address this question, we use a reference design flow provided by Synopsys and integrate in this flow academic tools and methodologies. The proposed design flow is used as a platform for analysing some novel algorithms and methodologies for optimisation in the context of digital circuits. The second question we answer is: Is possible to apply a systematic approach for power optimisation in the context of combinational digital circuits? The starting point is a selection of a suitable data structure which can easily incorporate information about delay, power, area and which then allows optimisation algorithms to be applied. In particular we address the implications of a systematic power optimisation methodologies and the potential degradation of other (often conflicting) parameters such as area or the delay of implementation. Finally, the third question which this thesis attempts to answer is: Is there a systematic approach for multi-objective optimisation of delay and power? A delay-driven power and power-driven delay optimisation is proposed in order to have balanced delay and power values. This implies that each power optimisation step is not only constrained by the decrease in power but also the increase in delay. Similarly, each delay optimisation step is not only governed with the decrease in delay but also the increase in power. The goal is to obtain multi-objective optimisation of digital circuits where the two conflicting objectives are power and delay. The logic synthesis and optimisation methodology is based on AND-Inverter Graphs (AIGs) which represent the functionality of the circuit. The switching activities and arrival times of circuit nodes are annotated onto an AND-Inverter Graph under the zero and a non-zero-delay model. We introduce then several reordering rules which are applied on the AIG nodes to minimise switching power or longest path delay of the circuit at the pre-technology mapping level. The academic Electronic Design Automation (EDA) tool ABC is used for the manipulation of AND-Inverter Graphs. We have implemented various combinatorial optimisation algorithms often used in Electronic Design Automation such as Simulated Annealing and Uniform Cost Search Algorithm. Simulated Annealing (SMA) is a probabilistic meta heuristic for the global optimization problem of locating a good approximation to the global optimum of a given function in a large search space. We used SMA to probabilistically decide between moving from one optimised solution to another such that the dynamic power is optimised under given delay constraints and the delay is optimised under given power constraints. A good approximation to the global optimum solution of energy constraint is obtained. Uniform Cost Search (UCS) is a tree search algorithm used for traversing or searching a weighted tree, tree structure, or graph. We have used Uniform Cost Search Algorithm to search within the AIG network, a specific AIG node order for the reordering rules application. After the reordering rules application, the AIG network is mapped to an AIG netlist using specific library cells. Our approach combines network re-structuring, AIG nodes reordering, dynamic power and longest path delay estimation and optimisation and finally technology mapping to an AIG netlist. A set of MCNC Benchmark circuits and large combinational circuits up to 100,000 gates have been used to validate our methodology. Comparisons for power and delay optimisation are made with the best synthesis scripts used in ABC. Reduction of 23% in power and 15% in delay with minimal overhead is achieved, compared to the best known ABC results. Also, our approach is also implemented on a number of processors with combinational and sequential components and significant savings are achieved.

The intra-Traveller debate on ‘Traveller ethnicity’ in the Republic of Ireland. A critical discourse analysis

This dissertation assesses from an under-explored angle the enduring contention over Travellers’ ethnic recognition in the Republic of Ireland, particularly over the last decade. The novelty of this study concerns not only its specific focus on and engagement with the debate on ‘Traveller ethnicity’ among Traveller activists. It also pertains to the examination of Travellers’ arguments for and against ethnicity in light of critical theorisations as well as insights from identity politics. Furthermore, the adoption of a Critical Discourse Analytical framework offers new perspectives to this controversy and its potential implications. Finally, this thesis’ relevance extends beyond the contention on ‘Traveller ethnicity’ in itself. It also draws attention to the complex dynamics of colonisation and appropriation between the global and the local. Particularly, it points to the interplay between international human rights discourses and the local ones, formulated by NGOs struggling for equality. In this way it sheds light on more general issues such as the dialectical potential of human rights discourses: the benefits and pitfalls of framing recognition claims in the legalistic terms of human rights. In this study it is argued that the contention on ‘Traveller ethnicity’ defies a simplistic polarisation between Irish Travellers and the Irish State since it has been simultaneously played out within the Travelling community. Specifically, this study explores how ‘Traveller ethnicity’ has been introduced, embraced, promoted and contested within Traveller politics to the point of becoming a hotly debated and divisive issue among Traveller activists and at the heart of the community itself. Putting Traveller activists centre-stage, their discourses for and against ‘Traveller ethnicity’ are examined and assessed against one another and their potential implications for Traveller politics, policies and identities are pointed out. Contending discourses are historically contextualised as the product of specific structural, material and discursive configurations of power and socio-economic relations within Irish society. Discourses for and against ‘Traveller ethnicity’ are assessed as being significant beyond the representational level. They are regarded as contributing to dialectically constitute Travellers’ ways of being, representing and acting. Furthermore these discourses are considered as sites and means of power struggles, whose stakes are not only words, but relate to issues of power and leadership within the Travelling community; adjudications over material resources; the adoption of certain policy approaches over others; and, finally, the consolidation of certain subject positions over others for Travellers to draw upon and relate to mainstream society. This study highlights an ongoing ideological struggle for the naturalisation of ‘Traveller ethnicity’ as a self-evident ‘fact’, which involves no active choice by Travellers themselves. Overall, ‘Traveller ethnicity’ appears to constitute an enduring source of dilemmas for the Travelling community. These revolve around the contradictory potential of ethnicity claims-making —both its perils and advantages— and its status as a potent political strategic resource that can both challenge and reinforce existing power relations, policies and identities.

Globalization and basketball in China: governance, market and culture

Chinese sports are developing under very complex and unique political, economic, and cultural circumstances in the global age. This study aims to investigate the process of globalization in basketball through an examination of its multidimensional manifestations. The study aligns itself with Ritzer’s (2003, 2007b) conceptualization of dichotomizing the process of globalization into grobalization and glocalization. On that basis, the trajectory of basketball globalization in China is identified as the result of a contextual and competing interplay between the penetration of the NBA and the consequent engagement of Chinese basketball. A qualitative methodological approach was conducted to achieve the research aim. Data were collected from a number of sources, including official documents and semi-structured interviews with relevant basketball participants. The study reveals that globalization and basketball in China, in the political and institutional dimension, is a conflicting process. The universalization of the NBA’s governance model could not be fully assimilated due to the centralization of power in the Chinese government, which is hindering the further professionalization and marketization of basketball. In the economic dimension, the globalization process is seen to interplay with the local basketball market, which is growing thanks to the adaption of the NBA’s marketing strategies. In the cultural dimension, the study demonstrates that the NBA has to some extent cosmopolitanized and consumerized Chinese basketball culture, while resistance from both the state and the Chinese people has risen, creolizing the globalization of basketball culture in China.

Current methods and advances in forecasting of wind power generation

Wind power generation differs from conventional thermal generation due to the stochastic nature of wind. Thus wind power forecasting plays a key role in dealing with the challenges of balancing supply and demand in any electricity system, given the uncertainty associated with the wind farm power output. Accurate wind power forecasting reduces the need for additional balancing energy and reserve power to integrate wind power. Wind power forecasting tools enable better dispatch, scheduling and unit commitment of thermal generators, hydro plant and energy storage plant and more competitive market trading as wind power ramps up and down on the grid. This paper presents an in-depth review of the current methods and advances in wind power forecasting and prediction. Firstly, numerical wind prediction methods from global to local scales, ensemble forecasting, upscaling and downscaling processes are discussed. Next the statistical and machine learning approach methods are detailed. Then the techniques used for benchmarking and uncertainty analysis of forecasts are overviewed, and the performance of various approaches over different forecast time horizons is examined. Finally, current research activities, challenges and potential future developments are appraised.

Politics, Power, PISA: a genealogy of mathematics education policy at second level in Ireland at the beginning of the 21st century

This thesis traces a genealogy of the discourse of mathematics education reform in Ireland at the beginning of the twenty first century at a time when the hegemonic political discourse is that of neoliberalism. It draws on the work of Michel Foucault to identify the network of power relations involved in the development of a single case of curriculum reform – in this case Project Maths. It identifies the construction of an apparatus within the fields of politics, economics and education, the elements of which include institutions like the OECD and the Government, the bureaucracy, expert groups and special interest groups, the media, the school, the State, state assessment and international assessment. Five major themes in educational reform emerge from the analysis: the arrival of neoliberal governance in Ireland; the triumph of human capital theory as the hegemonic educational philosophy here; the dominant role of OECD/PISA and its values in the mathematics education discourse in Ireland; the fetishisation of western scientific knowledge and knowledge as commodity; and the formation of a new kind of subjectivity, namely the subjectivity of the young person as a form of human-capital-to-be. In particular, it provides a critical analysis of the influence of OECD/PISA on the development of mathematics education policy here – especially on Project Maths curriculum, assessment and pedagogy. It unpacks the arguments in favour of curriculum change and lays bare their ideological foundations. This discourse contextualises educational change as occurring within a rapidly changing economic environment where the concept of the State’s economic aspirations and developments in science, technology and communications are reshaping both the focus of business and the demands being put on education. Within this discourse, education is to be repurposed and its consequences measured against the paradigm of the Knowledge Economy – usually characterised as the inevitable or necessary future of a carefully defined present.