In one embodiment, a method is illustrated including receiving a search query, parsing the search query to identify first and second search terms, determining a relationship between the first and second search terms based on their respective domain assignments, conducting a search based on the respective domain assignments, and displaying a result of the search based on the respective domain assignments, and the relationship between the first and second search terms, as at least one rephrasing of the search query.

Mixed initiative semantic search

Efficient allocation of resources in multiple heterogeneous Wireless Sensor Networks

A database system supporting persistent queries, comprising a client software application, a persistent query service, and a plurality of network-attached data sources. On receiving a request to create a persistent query from the client software application, the persistent query service: creates a query virtual table; parses the persistent query; creates a plurality of intermediate virtual tables; establishes listeners for the query virtual table; creates a plurality of data source virtual tables; causes the plurality of data source virtual tables to retrieve initial data from data sources; and propagates data via intermediate virtual tables to the persistent query virtual table. On detection of a data change in a data source, the associated data source virtual table causes the data change to propagate via intermediate virtual tables to the persistent query virtual table, and the client software application executes client code of at least one listener.

High performance real-time relational database system and methods for using same

In this paper, an information grouping paradigm for QoI in sensor networks is introduced. First, a definition of QoI is presented by analyzing the ITU's definition of QoS. Then, the concept of operational context to facilitate the dynamic binding of sensor resources to applications is presented and the 5WH principle ({why, when, where, what, who, how{) for summarizing the information needs of an application and the capabilities of the sensing resources is introduced. Finally, a brief treatise on metrics composition for relevancy parameters is presented.

A Letter Soup for the Quality of Information in Sensor Networks.

While Wireless Sensor Networks (WSNs) have been traditionally tasked with single applications, in recent years we have witnessed the emergence of Shared Sensor Networks (SSNs) as integrated cyber-physical system infrastructures for a multitude of applications. Instead of assuming an application-specific network design, SSNs allow the underlying infrastructure to be shared among multiple applications that can potentially belong to different users. On one hand, a potential benefit of such a design approach is to increase the utilization of sensing and communication resources, whenever the underlying network infrastructure covers the same geographic area and the sensor nodes monitor the same physical variables of common interest for different applications. On the other hand, compared with the existing application-specific design, the SSNs approach poses several research challenges with regard to different aspects of WSNs. In this article, we present a systematic literature survey on SSNs. The main goal of the article is to provide the reader with the opportunity to understand what has been done and what remains as open issues in this field, as well as which are the pivotal factors of this evolutionary design and how this kind of design can be exploited by a wide range of WSN applications.

A Systematic Review of Shared Sensor Networks

Parallel logical replication involves multiple apply threads running on a destination database server applying, in parallel, changes made by source transactions, where the changes of a single source transaction may be applied in parallel by multiple apply threads. An apply transaction for a source transaction may be committed by an apply thread independently of the commitment of any other apply transaction of the source transaction, that is, without coordinating the committing of another apply transaction executed by another apply thread for the source transaction. A configuration language is used to configure parallel logical replication. The language facilitates the configuration of various aspects of parallel logical replication, including the number of apply threads, partitioning schemes for the apply threads for partitioning change records between the apply threads, and various other aspects of parallel logical replication.

Scalable coordination aware static partitioning for database replication

Techniques are provided for dependency-aware transaction batching for data replication. A plurality of change records corresponding to a plurality of transactions is read. Inter-transaction dependency data is generated, the inter-transaction dependency data including at least one inter-transaction dependency relationship between a plurality of pending transactions. Each inter-transaction dependency relationship indicates that a first transaction is dependent on a second transaction. A batch transaction is generated based on the inter-transaction dependency data. The batch transaction includes at least one pending transaction of the plurality of pending transactions. The batch transaction is assigned to an apply process of a plurality of apply processes configured to apply batch transactions in parallel.

Dependency-aware transaction batching for data replication

Most existing research in wireless sensor networks focuses on optimally running a single application on top of a tailor-made and deployed network. However, as sensors become an integral part of our environments, we posit that sensor networks will be increasingly viewed as platforms that will be used to run several user applications simultaneously. Concurrently executing applications requires the network's resources to be shared across applications so as to make the best long-term utilization of the constrained devices and communications network. This resource sharing entails tradeoffs in the fidelity offered to individual applications. Fidelity is an application-dependent concept that can denote a variety of operational measures including communication latency, data quality, and redundancy. In this paper, we present a principled way to define the fidelity associated with an application given a particular allocation of the available resources. Given a desired set of applications to deploy, we also explore the impact of sharing resources among the applications in terms of fidelity degradation to individual applications. To this end, we provide an algorithm that determines the optimal subset of applications to deploy given the available resources and the potential impact on fidelity and evaluate it.

/pdf/supporting-multi-fidelity-aware-concurrent-applications-in-3fgbe558xb.pdf

Supporting multi-fidelity-aware concurrent applications in dynamic sensor networks

Queries are convenient abstractions for the discovery of information and services, as they offer content-based information access. In distributed settings, query semantics are well-defined, for example, queries are often designed to satisfy ACID transactional properties. When query processing is introduced in a dynamic network setting, achieving transactional semantics becomes complex due to the open and unpredictable environment. In this article, we propose a query processing model for mobile ad hoc and sensor networks that is suitable for expressing a wide range of query semantics; the semantics differ in the degree of consistency with which query results reflect the state of the environment during query execution. We introduce several distinct notions of consistency and formally express them in our model. A practical and significant contribution of this article is a protocol for query processing that automatically assesses and adaptively provides an achievable degree of consistency given the operational environment throughout its execution. The protocol attaches an assessment of the achieved guarantee to returned query results, allowing precise reasoning about a query with a range of possible semantics. We evaluate the performance of this protocol and demonstrate the benefits accrued to applications through examples drawn from an industrial application.

Semantic self-assessment of query results in dynamic environments

This paper focuses on the information gathering support needs for enterprises that operate over wireless mobile ad hoc networks While queries are a convenient way to obtain information, the highly dynamic nature of such networks makes it difficult to ensure a precise match between the results returned by a query and the actual state of the enterprise However, decisions can be made based on the perceived quality of the information retrieved; specialized query support is needed to control and assess the accuracy of the query results In this paper, we introduce the notion of inquiry mode to allow the user to exercise control over the query processing policy so as to match the level of accuracy to the requirements of the task In addition, we describe the use of query introspection, a process for assessing the fitness of a particular inquiry mode Both concepts are formalized, illustrated, and evaluated

/pdf/inquiry-and-introspection-for-non-deterministic-queries-in-20p34atsrm.pdf

Vasanth Rajamani

Papers

Scalable coordination aware static partitioning for database replication

Dependency-aware transaction batching for data replication

Supporting multi-fidelity-aware concurrent applications in dynamic sensor networks

Semantic self-assessment of query results in dynamic environments

Inquiry and Introspection for Non-deterministic Queries in Mobile Networks