1,969 research outputs found
Scalable Audience Reach Estimation in Real-time Online Advertising
Online advertising has been introduced as one of the most efficient methods
of advertising throughout the recent years. Yet, advertisers are concerned
about the efficiency of their online advertising campaigns and consequently,
would like to restrict their ad impressions to certain websites and/or certain
groups of audience. These restrictions, known as targeting criteria, limit the
reachability for better performance. This trade-off between reachability and
performance illustrates a need for a forecasting system that can quickly
predict/estimate (with good accuracy) this trade-off. Designing such a system
is challenging due to (a) the huge amount of data to process, and, (b) the need
for fast and accurate estimates. In this paper, we propose a distributed fault
tolerant system that can generate such estimates fast with good accuracy. The
main idea is to keep a small representative sample in memory across multiple
machines and formulate the forecasting problem as queries against the sample.
The key challenge is to find the best strata across the past data, perform
multivariate stratified sampling while ensuring fuzzy fall-back to cover the
small minorities. Our results show a significant improvement over the uniform
and simple stratified sampling strategies which are currently widely used in
the industry
Blazes: Coordination Analysis for Distributed Programs
Distributed consistency is perhaps the most discussed topic in distributed
systems today. Coordination protocols can ensure consistency, but in practice
they cause undesirable performance unless used judiciously. Scalable
distributed architectures avoid coordination whenever possible, but
under-coordinated systems can exhibit behavioral anomalies under fault, which
are often extremely difficult to debug. This raises significant challenges for
distributed system architects and developers. In this paper we present Blazes,
a cross-platform program analysis framework that (a) identifies program
locations that require coordination to ensure consistent executions, and (b)
automatically synthesizes application-specific coordination code that can
significantly outperform general-purpose techniques. We present two case
studies, one using annotated programs in the Twitter Storm system, and another
using the Bloom declarative language.Comment: Updated to include additional materials from the original technical
report: derivation rules, output stream label
BaseFs - Basically Acailable, Soft State, Eventually Consistent Filesystem for Cluster Management
A peer-to-peer distributed filesystem for community cloud management. https://github.com/glic3rinu/basef
David Mitchell's Ghostwritten and 'The Novel of Globalization': biopower and the Secret History of the Novel
David Mitchell's debut novel Ghostwritten (1999) not only depicts a globalized world; its peculiar formal organization also embodies the mode of relatedness that characterizes globalization. This article shows that the invisible, decentralized power that defines globalization can be understood as what Michel Foucault called biopower. As a novel of globalization, Mitchell's novel lays bare the hidden historical and theoretical affinities between the novel genre on the one hand and biopower on the other
Real-time predictive maintenance for wind turbines using Big Data frameworks
This work presents the evolution of a solution for predictive maintenance to
a Big Data environment. The proposed adaptation aims for predicting failures on
wind turbines using a data-driven solution deployed in the cloud and which is
composed by three main modules. (i) A predictive model generator which
generates predictive models for each monitored wind turbine by means of Random
Forest algorithm. (ii) A monitoring agent that makes predictions every 10
minutes about failures in wind turbines during the next hour. Finally, (iii) a
dashboard where given predictions can be visualized. To implement the solution
Apache Spark, Apache Kafka, Apache Mesos and HDFS have been used. Therefore, we
have improved the previous work in terms of data process speed, scalability and
automation. In addition, we have provided fault-tolerant functionality with a
centralized access point from where the status of all the wind turbines of a
company localized all over the world can be monitored, reducing O&M costs
The Struggle Itself Toward the Heights Is Enough to Fill a Man\u27s Heart: Calling, Moral Duty, Meaningfulness and Existential Self of Zookeepers
Applying Existential Sociology (Douglas & Johnson 1977, Manning 1973, Lyman and Scott 1989, Kotarba and Fontana 1984) as a theoretical foundation, this thesis endeavors to formulate first-order experiential understanding of zookeepers. Utilized is a mixed method approach comprising the survey and interview methods to explore zookeeper sense of calling as a moral duty, meaningfulness of work, and the possible connections formed with animals under their care (Bunderson & Thompson 2009, Spreitzer 1995, Wrzesnesweki et al 1997, and Pratt and Ashforth 2003, Hosey & Melfi 2010). Thirty zookeepers completed questionnaires containing measures of sense of calling, moral duty, work meaningfulness and human-animal bonds. Fifteen zookeepers submitted to semi-structured interviews. Results revealed high sense of calling and moral duty among zookeepers. Quantitative analysis of the study variables revealed a moderate positive association between zookeeper sense of calling and sense of perceived moral duty. Sense of calling for the occupation of zookeeper and work meaningfulness were not statistically related (rs (28) = .541, p\u3c .122). Human-animal bond (Hosey and Melfi 2010) was found among zookeepers. Zookeeper connections made with animals under their care were profound and meaningful. This study helps unravel the complexities of sensing a calling to an occupation and the interrelationship between occupationally-based sense of moral duty and perceived work meaningfulness
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