Physical Sciences and Mathematics Commons^™

Partially Materialized Digest Scheme: An Efficient Verification Method For Outsourced Databases, Kyriakos Mouratidis, Dimitris Sacharidis, Hwee Hwa Pang

Kyriakos MOURATIDIS

In the outsourced database model, a data owner publishes her database through a third-party server; i.e., the server hosts the data and answers user queries on behalf of the owner. Since the server may not be trusted, or may be compromised, users need a means to verify that answers received are both authentic and complete, i.e., that the returned data have not been tampered with, and that no qualifying results have been omitted. We propose a result verification approach for one-dimensional queries, called Partially Materialized Digest scheme (PMD), that applies to both static and dynamic databases. PMD uses separate indexes …

Associative Search Network: A Reinforcement Learning Associative Memory, Andrew Barto, Richard Sutton, Peter Brouwer

Andrew G. Barto

An associative memory system is presented which does not require a "teacher" to provide the desired associations. For each input key it conducts a search for the output pattern which optimizes an external payoff or reinforcement signal. The associative search network (ASN) combines pattern recognition and function optimization capabilities in a simple and effective way. We define the associative search problem, discuss conditions under which the associative search network is capable of solving it, and present results from computer simulations. The synthesis of sensory-motor control surfaces is discussed as an example of the associative search problem.

Identifying Useful Subgoals In Reinforcement Learning By Local Graph Partitioning, Özgür Şimşek, Alicia Wolfe, Andrew Barto

Andrew G. Barto

We present a new subgoal-based method for automatically creating useful skills in reinforcement learning. Our method identifies subgoals by partitioning local state transition graphs—those that are constructed using only the most recent experiences of the agent. The local scope of our subgoal discovery method allows it to successfully identify the type of subgoals we seek—states that lie between two densely-connected regions of the state space—while producing an algorithm with low computational cost.

Linear Least-Squares Algorithms For Temporal Difference Learning, Steven Bradtke, Andrew Barto

Andrew G. Barto

We introduce two new temporal difference (TD) algorithms based on the theory of linear leastsquares function approximation. We define an algorithm we call Least-Squares TD (LS TD) for which we prove probability-one convergence when it is used with a function approximator linear in the adjustable parameters. We then define a recursive version of this algorithm, Recursive Least-Squares TD (RLS TD). Although these new TD algorithms require more computation per time-step than do Sutton's TD(A) algorithms, they are more efficient in a statistical sense because they extract more information from training experiences. We describe a simulation experiment showing the substantial improvement …

Lego Rover Control, Gang-Ryung Uh

Gang-Ryung Uh

Is Necessity The Mother Of Innovation? The Adoption And Use Of Web Technologies Among Congressional Offices, Kevin Esterling, David Lazer, Michael Neblo

David Lazer

From first paragraph: Communication between legislator and constituents is fundamental to effective democratic representation, and devising the institutional means for citizen/legislator communication stands as one of the core and persistent problems in the practice of democracy. A legislator needs information about the preferences, ideals, norms, and beliefs of her constituents in order to do her job well. Similarly, citizens need information about the actions and decisions of their representative in order to maintain appropriate accountability. But as national problems become more complex, and as the political process grows more and more dominated by experts and organized groups, it is becoming …

The Protection Of Rights Management Information: Modernization Or Cup Half Full?, Mark Perry

Mark Perry

Many papers in this collection discuss the history and development of Bill C-32, An Act to Amend the Copyright Act, introduced into the Canadian Parliament on 2 June 2010, so that analysis will not be duplicated here. Among the failures of copyright reform has been the lack of addressing the required “balancing” of proprietary rights on the one hand, with user rights and the public domain on the other. Rights Management Information (RMI) can aid in this balancing. The RMI of a work is simply data that provide iden- tification of rights related to that work, either directly or indirectly. …

A Web 2.0/Web3d Hybrid Platform For Engaging Students In E-Learning Environments, Penny De Byl, Janet Taylor

Penny de Byl

This paper explores the Web 2.0 ethos with respect to the application of pedagogy within 3D online virtual environments. 3D worlds can create a synthetic experience capturing the essence of being in a particular world or context. The AliveX3D platform adopts the Web 2.0 ethos and applies it to online 3D virtual environment forming a Web 2.0/Web3D hybrid that has wider usability than previous alternatives. This combined with the AliveX3D Scene Editor allows learning experiences, which are controlled by the learner, appear authentic and facilitate collaboration conversations to be developed simultaneously. This immersion enables learners to negotiate meaning based on …

Use A Mobile Phone To Control Zigbee Enabled Harex Dynamic Natural Light Leds, Gang-Ryung Uh

Gang-Ryung Uh

Performance Analysis Of Real-Time Component Architectures: An Enhanced Model Interchange Approach, Gabriel Moreno, Connie Smith

Gabriel A. Moreno

Model interchange approaches support the analysis of software architecture and design by enabling a variety of tools to exchange performance models using a common schema. This paper builds on the Software Performance Model Interchange Format (S-PMIF), extending it to support the analysis of real-time systems and adapting it to be suitable for implementation with modeling frameworks such as MOF or EMF. This enhances the model interchange process by making it possible to define model-to-model transformations from design models into software performance models. The paper addresses real-time system designs expressed in CCL and their transformation into the S-PMIF for additional performance …

Guest Editorial: Special Issue On Software, Maintenance And Evolution, Panos Linos

Panos K. Linos

Software maintenance and evolution continues to play a vital role in the development of software systems. It is widely acknowledged that the majority of development effort, and thereby expenditure, is allocated to postinitial release activity. This activity, which takes place after the software has seen its first release, is known as software maintenance (or software evolution).

Dynamic Pickup And Delivery Problems, Gerardo Berbeglia

Gerardo Berbeglia

No abstract provided.

Association-Based Image Retrieval, Arun D. Kulkarni

Arun Kulkarni

No abstract provided.

From Artifacts To Aggregations: Modeling Scientific Life Cycles On The Semantic Web, Alberto Pepe, Matthew Mayernik, Christine Borgman, Herbert Van De Sompel

Alberto Pepe

In the process of scientific research, many information objects are generated, all of which may remain valuable indefinitely. However, artifacts such as instrument data and associated calibration information may have little value in isolation; their meaning is derived from their relationships to each other. Individual artifacts are best represented as components of a life cycle that is specific to a scientific research domain or project. Current cataloging practices do not describe objects at a sufficient level of granularity nor do they offer the globally persistent identifiers necessary to discover and manage scholarly products with World Wide Web standards. The Open …