17,270 research outputs found
Multi-tenant Pub/Sub processing for real-time data streams
Devices and sensors generate streams of data across a diversity of locations and protocols. That data usually reaches a central platform that is used to store and process the streams. Processing can be done in real time, with transformations and enrichment happening on-the-fly, but it can also happen after data is stored and organized in repositories. In the former case, stream processing technologies are required to operate on the data; in the latter batch analytics and queries are of common use.
This paper introduces a runtime to dynamically construct data stream processing topologies based on user-supplied code. These dynamic topologies are built on-the-fly using a data subscription model defined by the applications that consume data. Each user-defined processing unit is called a Service Object. Every Service Object consumes input data streams and may produce output streams that others can consume. The subscription-based programing model enables multiple users to deploy their own data-processing services. The runtime does the dynamic forwarding of data and execution of Service Objects from different users. Data streams can originate in real-world devices or they can be the outputs of Service Objects.
The runtime leverages Apache STORM for parallel data processing, that combined with dynamic user-code injection provides multi-tenant stream processing topologies. In this work we describe the runtime, its features and implementation details, as well as we include a performance evaluation of some of its core components.This work is partially supported by the European Research Council (ERC) un-
der the EU Horizon 2020 programme (GA 639595), the Spanish Ministry of
Economy, Industry and Competitivity (TIN2015-65316-P) and the Generalitat
de Catalunya (2014-SGR-1051).Peer ReviewedPostprint (author's final draft
Employment Retention and Advancement Project: Results from the Post-Assistance Self-Sufficiency (PASS) Program in Riverside, California
A random assignment evaluation of a voluntary postemployment program for workers who recently left welfare shows participants had increased employment and earnings during the first two years of follow-up
Automatic Dataset Labelling and Feature Selection for Intrusion Detection Systems
The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Correctly labelled datasets are commonly required. Three particular scenarios are highlighted, which showcase this need. When using supervised Intrusion Detection Systems (IDSs), these systems need labelled datasets to be trained. Also, the real nature of the analysed datasets must be known when evaluating the efficiency of the IDSs when detecting intrusions. Another scenario is the use of feature selection that works only if the processed datasets are labelled. In normal conditions, collecting labelled datasets from real networks is impossible. Currently, datasets are mainly labelled by implementing off-line forensic analysis, which is impractical because it does not allow real-time implementation. We have developed a novel approach to automatically generate labelled network traffic datasets using an unsupervised anomaly based IDS. The resulting labelled datasets are subsets of the original unlabelled datasets. The labelled dataset is then processed using a Genetic Algorithm (GA) based approach, which performs the task of feature selection. The GA has been implemented to automatically provide the set of metrics that generate the most appropriate intrusion detection results
Juan Manuel (1282-1348) e as profissões ‘judeus’ no El Conde Lucanor: um modelo medieval ibérico de relação de grupo
This article aims to analyze the personal relationship between Christian writer Juan Manuel (1282-1348) and the Jewish community in his collection of didactic exempla, El Conde Lucanor [Count Lucanor]. Through the theory of out-group interaction, and the mechanisms of re-fencing and extended contact hypothesis, I will examine the relationship of trust and respect reflected between the author and the Jews through the portrayal of some professions attributed to that community by popular folklore, such as money lenders, physicians, alchemists, nigromancers and sorcerers, as shown in the introduction and four exempla of the book. I will analyze several literary techniques employed by the author in regards to these ‘Jewish occupations’ as a resource to minimize the social rejection towards the Jew, and an example of a complex convivencia [cohabitation] that shaped XIV-century Castilian Christian-Jewish relations.El objetivo de este trabajo analiza la relación personal del escritor castellano Juan Manuel (1282-1348) y la comunidad judía dentro de la colección de exempla de El Conde Lucanor. Tomando como base la teoría de interacción de grupos y los mecanismos de re-fencing y extended contact hypothesis, examinaré la estrecha relación de respeto que el autor proyecta sobre el judío en la introducción y cuatro exempla de la obra tomando como referencia varias profesiones que el folklore atribuyó a este grupo religioso: prestamistas, físicos, alquimistas, nigromantes y hechiceros. Analizaré las técnicas literarias empleadas en los estereotipos asignados hacia estas ocupaciones ‘judías’, como un recurso de autor para minimizar el rechazo social que sufría esta comunidad, así como un ejemplo de una compleja convivencia que marcó las relaciones cristiano-judías de la Castilla del siglo XIV
Visualization of Internet Web pages based on authority and word frequency
The growth, accessibility, and integration of the World Wide Web with contemporary information utilization provides a rich domain in which to explore information retrieval systems. One approach in the evolution of retrieval systems couples successful and long-standing techniques of information retrieval with new techniques, such as visualization. The system developed and reported in this thesis takes this approach. It builds upon well-known techniques of information retrieval including stemming, keyword matching, and cosine similarity. It also incorporates the new and relatively successful hubs and authority approach, which describes Web documents by their reference by other documents. Finally, it develops a new and unique approach to document visualization that encodes these metrics in a single visual representation. This new, easily scannable representation, allows the user to interact with search results as the scope of search is expanded dynamically across the Web
The Consistency dimension and distribution-dependent learning from queries
We prove a new combinatorial characterization of polynomial
learnability from equivalence queries, and state some of its
consequences relating the learnability of a class with the
learnability via equivalence and membership queries of its
subclasses obtained by restricting the instance space.
Then we propose and study two models of query learning in which there
is a probability distribution on the instance space, both as an
application of the tools developed from the combinatorial
characterization and as models of independent interest.Postprint (published version
- …