32 research outputs found
Resource Allocation for Multiple Concurrent In-Network Stream-Processing Applications
This paper investigates the operator mapping problem for in-network stream-processing applications. In-network stream-processing amounts to applying one or more trees of operators in steady-state, to multiple data objects that are continuously updated at different locations in the network. The goal is to compute some final data at some desired rate. Different operator trees may share common subtrees. Therefore, it may be possible to reuse some intermediate results in different application trees. The first contribution of this work is to provide complexity results for different instances of the basic problem, as well as integer linear program formulations of various problem instances. The second second contribution is the design of several polynomial-time heuristics. One of the primary objectives of these heuristics is to reuse intermediate results shared by multiple applications. Our quantitative comparisons of these heuristics in simulation demonstrates the importance of choosing appropriate processors for operator mapping. It also allow us to identify a heuristic that achieves good results in practice
iSchool Health and Medical Research Initiatives and Opportunities
The Annual iConference offers an important opportunity for information sharing among member iSchools. Proposed for iConference 09 is a Roundtable Discussion that provides a forum for information sharing about existing and planned iSchool initiatives, and discussion of opportunities related to Health and Medical Research. Because of the transdisciplinary scope of research problems and practical demands in relation to Health and Medical Research, initiatives in these areas offer significant opportunities for cross-disciplinary research collaboration and interdisciplinary partnership with other units in the development of professional training programs
The Open Provenance Model: Core Specification (v1.1)
The Open Provenance Model is a model of provenance that is designed to meet the following requirements: (1) To allow provenance information to be exchanged between systems, by means of a compatibility layer based on a shared provenance model. (2) To allow developers to build and share tools that operate on such a provenance model. (3) To define provenance in a precise, technology-agnostic manner. (4) To support a digital representation of provenance for any "thing", whether produced by computer systems or not. (5) To allow multiple levels of description to coexist. (6) To define a core set of rules that identify the valid inferences that can be made on provenance representation. This document contains the specification of the Open Provenance Model (v1.1) resulting from a community-effort to achieve inter-operability in the Third Provenance Challenge
Towards Low Overhead Provenance Tracking in Near Real-Time Stream Filtering
Abstract. Data streams flowing from the physical environment are as unpredictable as the environment itself. Radars go down, long haul networks drop packets, and readings are corrupted on the wire. Yet the data driven scientific models and data mining algorithms do not necessarily account for the inaccuracies when assimilating the data. Low overhead provenance collection partially solves this problem. We propose a data model and collection model for near real time provenance collection. We define a system architecture for stream provenance tracking and motivate with a real-world application in meteorology forecasting.