22 research outputs found

    An erasure-resilient and compute-efficient coding scheme for storage applications

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    Driven by rapid technological advancements, the amount of data that is created, captured, communicated, and stored worldwide has grown exponentially over the past decades. Along with this development it has become critical for many disciplines of science and business to being able to gather and analyze large amounts of data. The sheer volume of the data often exceeds the capabilities of classical storage systems, with the result that current large-scale storage systems are highly distributed and are comprised of a high number of individual storage components. As with any other electronic device, the reliability of storage hardware is governed by certain probability distributions, which in turn are influenced by the physical processes utilized to store the information. The traditional way to deal with the inherent unreliability of combined storage systems is to replicate the data several times. Another popular approach to achieve failure tolerance is to calculate the block-wise parity in one or more dimensions. With better understanding of the different failure modes of storage components, it has become evident that sophisticated high-level error detection and correction techniques are indispensable for the ever-growing distributed systems. The utilization of powerful cyclic error-correcting codes, however, comes with a high computational penalty, since the required operations over finite fields do not map very well onto current commodity processors. This thesis introduces a versatile coding scheme with fully adjustable fault-tolerance that is tailored specifically to modern processor architectures. To reduce stress on the memory subsystem the conventional table-based algorithm for multiplication over finite fields has been replaced with a polynomial version. This arithmetically intense algorithm is better suited to the wide SIMD units of the currently available general purpose processors, but also displays significant benefits when used with modern many-core accelerator devices (for instance the popular general purpose graphics processing units). A CPU implementation using SSE and a GPU version using CUDA are presented. The performance of the multiplication depends on the distribution of the polynomial coefficients in the finite field elements. This property has been used to create suitable matrices that generate a linear systematic erasure-correcting code which shows a significantly increased multiplication performance for the relevant matrix elements. Several approaches to obtain the optimized generator matrices are elaborated and their implications are discussed. A Monte-Carlo-based construction method allows it to influence the specific shape of the generator matrices and thus to adapt them to special storage and archiving workloads. Extensive benchmarks on CPU and GPU demonstrate the superior performance and the future application scenarios of this novel erasure-resilient coding scheme

    Rebuilding the Iron Cage: Post-Failure Organizing in Newspapers and Investment Banks

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    Organizational failure is an incomplete process because routines and norms persist through employee careers. Qualitative interviews with former employees from four newspapers and two investment banks, all of which are bankrupt or disbanded, demonstrate ongoing utilization of routines and ongoing compliance to norms despite severed connections to the failed firm. Routines are most likely to persist when they relate to low-volatility processes that do not require maintenance to ensure ongoing accessibility. Characteristics that make norms transferable are also identified. Adherence to aesthetic and pragmatic norms depends on how well they fit into new occupational contexts: uptake varies in proportion to the similarity between the failed firm and the new occupational setting of a failure survivor. Justice-oriented norms are not context-dependent; they persist regardless of post-failure employment outcomes. In fact, justice-oriented norms are found to drive the selection of new occupations as journalists seek normative consistency in their careers and some investment bankers change careers to reclaim a sense of purpose lost in banking. These observations hold whether survivors find employment in incumbent firms, entrepreneurial projects, or as freelancers. As survivors adapt work practices, their efforts constitute a form of inter-organizational innovation that generates organizational heterogeneity within unstable industries. Post-failure continuity provides an important and largely undocumented mechanism for the preservation of organizational attributes and the diversification of organizational form amidst crisis, an adaptive process that reconsiders the normative environment of a business and selectively discards assumptions about how firms ought to be. Survivors of failure often face a dilemma in deciding whether to attempt to re-create an occupational setting similar to the firm that failed or to go a different direction. This work takes up this dilemma, asking what insight business ethics research can provide for those who might wonder about the purpose of their firms. A theory of property is used to articulate a normative argument: firms should fail when they are unable to cover their debts and externalities, and firms should survive when they generate surplus value. The dissertation contributes to organizational theories of evolution, to the study of career trajectories, and to a life-cycle approach to business ethics

    Making the Frontier: Contested Development on the Coast of Patagonia

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    This project uses critical development theory to examine relationships between rural residents pursuing multiple livelihoods in remote spaces, globalized industries that dominate these sparsely-populated edges of the global economy, and state agents tasked with serving both groups in Chile’s Aysén Region. Since the 1980s, southern Chile has emerged as an aquaculture frontier. But state officials, aquaculture operators, and rural residents enact the frontier differently based on their distinct social projects. Following Chile’s return to democracy in 1990, state officials introduced new social programs and conservation initiatives. They provided services, subsidies, and public employment which rural residents incorporated into their longstanding pursuit of multiple livelihoods. This allowed for the maintenance of a delicate status quo. Residents benefitted from these programs while continuing semi-subsistence activities and aquaculture grew exponentially, diversifying Chile’s export sector and fueling the national economy without employing rural residents. A series of harmful algal blooms (HABs), however, have upset this status quo. These dynamic phenomena exhibit a toxic vitality and the distributed causality behind them makes them difficult to predict even as they grow more severe. Evidence suggests that HABs, which were once unheard of in southern Chile, have worsened due to aquaculture operations and rising temperatures in the southern Pacific. Whatever their causes, they have destabilized the region: residents of Aysén now regularly protest state inaction in the face of threats to their livelihoods and the degradation of their once pristine coastline. Whereas before both state officials and rural residents saw the sustained occupation and development of the coast as their primary goal, it has become clear that the development favored by state officials—one that privileges multinational corporations over rural workers and growth over sustainability—is incompatible with the goals of residents. Thus, HABs are more than symptoms of global climate change and coastal contamination; they inspire the contestation, negotiation, and reorganization of Chile’s development project. Through strikes, blockades, and ship seizures, rural residents pressure state officials to distribute public funds as compensation for their lost livelihoods and the contamination of their landscape, effectively linking the moral and political economies in defense of their communities.Doctor of Philosoph

    Railway Master Mechanic (v.39)

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    To The Angel of Schooling, Write: Redeeming the Telos of Schooling as a Liturgical Institution, And the Role of the School Administrator as Peace-Weaver, Through the Lens of Prophetic Imagination

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    The purpose of this dissertation is to critique the institution of mass schooling by holding up the failure of both its liturgy and its pedagogies as part of the larger failure inherent in the overarching telos of the marketplace. The problem addressed here is that schooling operates as a religious institution through its proffering a sacred cosmology around what I will conceptualize as “The Religion of the Marketplace” that shapes students in the imago dei of the Homo Economicus whose hearts are shaped to worship the god, Mammon, by the disordered love of avarice to find peace, contentment, and happiness through the theology of consumption. This dissertation examines the schoolhouse as a liturgical institution, arguing not that schools should be religious, but rather that they are “re-ligious” (Baker and Letendre, 2005; Meyer, 2009) in that they bind us to what Charles Taylor (2004) describes as social imaginaries (ways of seeing and being in the world) that then become “religious” (held as sacred) for a given culture when they are legitimated, replicated and perpetuated through their specific pedagogies and practices. Using exegesis of biblical texts and a historical exploration of the vice of avarice, I will argue that the cultivation of Mammon undermines both moral and political health because it erodes empathy and keeps one’s focus on the disordered love (Augustine, 1958) of one’s own self-gratification and –glorification. This work seeks to address the moral, philosophical, political, and theological problems that are deeper than the issues addressed by the current public discourse on school reform. By theorizing the concepts of “Mammon” and “Liturgical Institutions” (Smith, 2009), this inquiry explores the ways in which the Religion of the Marketplace shapes a theology of consumption that drives schooling, and the monstrous consequences of its so doing. This conceptualization opens the way to speak about the need for the school administrator to act as prophetic peace-weaver, the one tasked within the organization of a given school to usher in new modes of discourse and praxis in order to see not school reform, but school redemption occur
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