16,917 research outputs found

    Multi-Objective Trust-Region Filter Method for Nonlinear Constraints using Inexact Gradients

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    In this article, we build on previous work to present an optimization algorithm for nonlinearly constrained multi-objective optimization problems. The algorithm combines a surrogate-assisted derivative-free trust-region approach with the filter method known from single-objective optimization. Instead of the true objective and constraint functions, so-called fully linear models are employed, and we show how to deal with the gradient inexactness in the composite step setting, adapted from single-objective optimization as well. Under standard assumptions, we prove convergence of a subset of iterates to a quasi-stationary point and if constraint qualifications hold, then the limit point is also a KKT-point of the multi-objective problem

    Barren plateaus in quantum tensor network optimization

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    We analyze the barren plateau phenomenon in the variational optimization of quantum circuits inspired by matrix product states (qMPS), tree tensor networks (qTTN), and the multiscale entanglement renormalization ansatz (qMERA). We consider as the cost function the expectation value of a Hamiltonian that is a sum of local terms. For randomly chosen variational parameters we show that the variance of the cost function gradient decreases exponentially with the distance of a Hamiltonian term from the canonical centre in the quantum tensor network. Therefore, as a function of qubit count, for qMPS most gradient variances decrease exponentially and for qTTN as well as qMERA they decrease polynomially. We also show that the calculation of these gradients is exponentially more efficient on a classical computer than on a quantum computer

    Radical Left Parties and the Role of Euroscepticism

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    Globalization has shifted the political competition landscape in Western Europe. Extensive research has studied the impact of this on the radical right, yet little attention has been paid to the radical left. This dissertation, comprised of three papers, analyses the impact of the increased European integration emphasis on the radical left. My first paper analyses whether there is a beneficial policy position for the radical left on European integration. The chapter finds that there is an electoral benefit to a Eurosceptic position for radical left parties but also shows that this benefit is constrained when a Eurosceptic competitor, i.e. radical right party, enters the party system. My second paper follows from this and examines an alternative approach for the radical left on European integration. While the benefit of a Eurosceptic position can be constrained, blurring the position on European integration can help avoid losing pro-EU voters. The chapter finds that position blurring on EU integration is beneficial when there is electorate polarization but harmful when the electorate is in consensus on EU integration. When there is consensus, radical left parties benefit from a clear position on EU integration. My third paper is co-authored with Royce Carroll and zooms into the findings of the first two chapters by examining the demand side of Euroscepticism. The paper finds that European integration is an important issue for vote choice of the electorate. The results of the chapter show that the more Eurosceptic voters are, the higher their propensity to vote for a radical left party becomes. These three papers demonstrate how the issue of European integration is in the centre of radical left strategy from a supply and demand side perspective. This thesis contributes to the literature by providing a detailed understanding of the success of small parties beyond their issue ownership

    Does the Interaction between ICT Diffusion and Economic Growth Reduce CO2 Emissions? An ARDL Approach

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    In recent years, information and communication technology (ICT) and its impact on economic growth and CO2 emission has become a hot topic of debate; however, little research has been conducted regarding the impact of the interaction between ICT and economic growth on CO2 emission. The study tries to evaluate empirically the impact of ICT and economic growth on CO2 emissions of Tunisia and Morocco for the period 1980–2018, based on the Auto-Regressive Distributive Lag (ARDL) analysis. Findings demonstrate that ICT and economic growth affect positively and significantly the CO2 emissions in the short and long term in both Tunisia and Morocco; however, the direct and positive effect of economic growth on CO2 emissions can be ameliorated by introducing the interaction between ICT and economic growth. The Toda-Yamamoto Granger causality test reveals that bi-directional causality is running between economic growth and CO2 emissions in both countries. On the other hand, our obtained results express that there is a unidirectional causality running from ICT to CO2 emissions in both countries. So, the promotion of ICT can be considered one of the important strategies introduced to mitigate CO2 emissions. Then, introducing green ICT projects in various sectors of an economy is a better choice for policy makers to decrease the CO2 emissions

    Building body identities - exploring the world of female bodybuilders

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    This thesis explores how female bodybuilders seek to develop and maintain a viable sense of self despite being stigmatized by the gendered foundations of what Erving Goffman (1983) refers to as the 'interaction order'; the unavoidable presentational context in which identities are forged during the course of social life. Placed in the context of an overview of the historical treatment of women's bodies, and a concern with the development of bodybuilding as a specific form of body modification, the research draws upon a unique two year ethnographic study based in the South of England, complemented by interviews with twenty-six female bodybuilders, all of whom live in the U.K. By mapping these extraordinary women's lives, the research illuminates the pivotal spaces and essential lived experiences that make up the female bodybuilder. Whilst the women appear to be embarking on an 'empowering' radical body project for themselves, the consequences of their activity remains culturally ambivalent. This research exposes the 'Janus-faced' nature of female bodybuilding, exploring the ways in which the women negotiate, accommodate and resist pressures to engage in more orthodox and feminine activities and appearances

    Towards a more just refuge regime: quotas, markets and a fair share

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    The international refugee regime is beset by two problems: Responsibility for refuge falls disproportionately on a few states and many owed refuge do not get it. In this work, I explore remedies to these problems. One is a quota distribution wherein states are distributed responsibilities via allotment. Another is a marketized quota system wherein states are free to buy and sell their allotments with others. I explore these in three parts. In Part 1, I develop the prime principles upon which a just regime is built and with which alternatives can be adjudicated. The first and most important principle – ‘Justice for Refugees’ – stipulates that a just regime provides refuge for all who have a basic interest in it. The second principle – ‘Justice for States’ – stipulates that a just distribution of refuge responsibilities among states is one that is capacity considerate. In Part 2, I take up several vexing questions regarding the distribution of refuge responsibilities among states in a collective effort. First, what is a state’s ‘fair share’? The answer requires the determination of some logic – some metric – with which a distribution is determined. I argue that one popular method in the political theory literature – a GDP-based distribution – is normatively unsatisfactory. In its place, I posit several alternative metrics that are more attuned with the principles of justice but absent in the political theory literature: GDP adjusted for Purchasing Power Parity and the Human Development Index. I offer an exploration of both these. Second, are states required to ‘take up the slack’ left by defaulting peers? Here, I argue that duties of help remain intact in cases of partial compliance among states in the refuge regime, but that political concerns may require that such duties be applied with caution. I submit that a market instrument offers one practical solution to this problem, as well as other advantages. In Part 3, I take aim at marketization and grapple with its many pitfalls: That marketization is commodifying, that it is corrupting, and that it offers little advantage in providing quality protection for refugees. In addition to these, I apply a framework of moral markets developed by Debra Satz. I argue that a refuge market may satisfy Justice Among States, but that it is violative of the refugees’ welfare interest in remaining free of degrading and discriminatory treatment

    Embodying entrepreneurship: everyday practices, processes and routines in a technology incubator

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    The growing interest in the processes and practices of entrepreneurship has been dominated by a consideration of temporality. Through a thirty-six-month ethnography of a technology incubator, this thesis contributes to extant understanding by exploring the effect of space. The first paper explores how class structures from the surrounding city have appropriated entrepreneurship within the incubator. The second paper adopts a more explicitly spatial analysis to reveal how the use of space influences a common understanding of entrepreneurship. The final paper looks more closely at the entrepreneurs within the incubator and how they use visual symbols to develop their identity. Taken together, the three papers reject the notion of entrepreneurship as a primarily economic endeavour as articulated through commonly understood language and propose entrepreneuring as an enigmatic attractor that is accessed through the ambiguity of the non-verbal to develop the ‘new’. The thesis therefore contributes to the understanding of entrepreneurship and proposes a distinct role for the non-verbal in that understanding

    Post-Millennial Queer Sensibility: Collaborative Authorship as Disidentification in Queer Intertextual Commodities

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    This dissertation is examining LGBTQ+ audiences and creatives collaborating in the creation of new media texts like web shows, podcasts, and video games. The study focuses on three main objects or media texts: Carmilla (web series), Welcome to Night Vale (podcast), and Undertale (video game). These texts are transmedia objects or intertextual commodities. I argue that by using queer gestures of collaborative authorship that reaches out to the audience for canonical contribution create an emerging queer production culture that disidentifies with capitalism even as it negotiates capitalistic structures. The post-millennial queer sensibility is a constellation of aesthetics, self-representation, alternative financing, and interactivity that prioritizes community, trust, and authenticity using new technologies for co-creation. Within my study, there are four key tactics or queer gestures being explored: remediation, radical ambiguity and multi-forms as queer aesthetics, audience self-representation, alternative financing like micropatronage & licensed fan-made merchandise, and interactivity as performance. The goal of this project is to better understand the changing conceptions of authorship/ownership, canon/fanon (official text/fan created extensions), and community/capitalism in queer subcultures as an indicator of the potential change in more mainstream cultural attitudes. The project takes into consideration a variety of intersecting identities including gender, race, class, and of course sexual orientation in its analysis. By examining the legal discourse around collaborative authorship, the real-life production practices, and audience-creator interactions and attitudes, this study provides insight into how media creatives work with audiences to co-create self-representative media, the motivations, and rewards for creative, audiences, and owners. This study aims to contribute towards a fuller understanding of queer production cultures and audience reception of these media texts, of which there is relatively little academic information. Specifically, the study mines for insights into the changing attitudes towards authorship, ownership, and collaboration within queer indie media projects, especially as these objects are relying on the self-representation of both audiences and creatives in the formation of the text

    The Reputations of Sir Francis Burdett

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    Political Islam and grassroots activism in Turkey : a study of the pro-Islamist Virtue Party's grassroots activists and their affects on the electoral outcomes

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    This thesis presents an analysis of the spectacular rise of political Islam in Turkey. It has two aims: first to understand the underlying causes of the rise of the Welfare Party which -later became the Virtue Party- throughout the 1990s, and second to analyse how grassroots activism influenced this process. The thesis reviews the previous literature on the Islamic fundamentalist movements, political parties, political party systems and concentrates on the local party organisations and their effects on the party's electoral performance. It questions the categorisation of Islamic fundamentalism as an appropriate label for this movement. An exploration of such movements is particularly important in light of the event of 11`x' September. After exploring existing theoretical and case studies into political Islam and party activism, I present my qualitative case study. I have used ethnographic methodology and done participatory observations among grassroots activists in Ankara's two sub-districts covering 105 neighbourhoods. I examined the Turkish party system and the reasons for its collapse. It was observed that as a result of party fragmentation, electoral volatility and organisational decline and decline in the party identification among the citizens the Turkish party system has declined. However, the WP/VP profited from this trend enormously and emerged as the main beneficiary of this process. Empirical data is analysed in four chapters, dealing with the different aspects of the Virtue Party's local organisations and grassroots activists. They deal with change and continuity in the party, the patterns of participation, the routes and motives for becoming a party activist, the profile of party activists and the local party organisations. I explore what they do and how they do it. The analysis reveals that the categorisation of Islamic fundamentalism is misplaced and the rise of political Islam in Turkey cannot be explained as religious revivalism or the rise of Islamic fundamentalism. It is a political force that drives its strength from the urban poor which has been harshly affected by the IMF directed neoliberal economy policies. In conclusion, it is shown that the WP/VP's electoral chances were significantly improved by its very efficient and effective party organisations and highly committed grassroots activists
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