CUFID-query: accurate network querying through random walk based network flow estimation.

Science.gov (United States)

Jeong, Hyundoo; Qian, Xiaoning; Yoon, Byung-Jun

2017-12-28

Functional modules in biological networks consist of numerous biomolecules and their complicated interactions. Recent studies have shown that biomolecules in a functional module tend to have similar interaction patterns and that such modules are often conserved across biological networks of different species. As a result, such conserved functional modules can be identified through comparative analysis of biological networks. In this work, we propose a novel network querying algorithm based on the CUFID (Comparative network analysis Using the steady-state network Flow to IDentify orthologous proteins) framework combined with an efficient seed-and-extension approach. The proposed algorithm, CUFID-query, can accurately detect conserved functional modules as small subnetworks in the target network that are expected to perform similar functions to the given query functional module. The CUFID framework was recently developed for probabilistic pairwise global comparison of biological networks, and it has been applied to pairwise global network alignment, where the framework was shown to yield accurate network alignment results. In the proposed CUFID-query algorithm, we adopt the CUFID framework and extend it for local network alignment, specifically to solve network querying problems. First, in the seed selection phase, the proposed method utilizes the CUFID framework to compare the query and the target networks and to predict the probabilistic node-to-node correspondence between the networks. Next, the algorithm selects and greedily extends the seed in the target network by iteratively adding nodes that have frequent interactions with other nodes in the seed network, in a way that the conductance of the extended network is maximally reduced. Finally, CUFID-query removes irrelevant nodes from the querying results based on the personalized PageRank vector for the induced network that includes the fully extended network and its neighboring nodes. Through extensive

Performance of Point and Range Queries for In-memory Databases using Radix Trees on GPUs

Energy Technology Data Exchange (ETDEWEB)

Alam, Maksudul [ORNL; Yoginath, Srikanth B [ORNL; Perumalla, Kalyan S [ORNL

2016-01-01

In in-memory database systems augmented by hardware accelerators, accelerating the index searching operations can greatly increase the runtime performance of database queries. Recently, adaptive radix trees (ART) have been shown to provide very fast index search implementation on the CPU. Here, we focus on an accelerator-based implementation of ART. We present a detailed performance study of our GPU-based adaptive radix tree (GRT) implementation over a variety of key distributions, synthetic benchmarks, and actual keys from music and book data sets. The performance is also compared with other index-searching schemes on the GPU. GRT on modern GPUs achieves some of the highest rates of index searches reported in the literature. For point queries, a throughput of up to 106 million and 130 million lookups per second is achieved for sparse and dense keys, respectively. For range queries, GRT yields 600 million and 1000 million lookups per second for sparse and dense keys, respectively, on a large dataset of 64 million 32-bit keys.

Tune and Orbit feedbacks performance: a user perspective

CERN Document Server

Ponce, L

2012-01-01

The presentation will present the performance and issues of tune and orbit feedbacks seen from the user (operation) perspective. Some statistics on the beam dumps causes will be presented to emphasize the two main limitations of the system : the issue on the tune measurement and the triggering of the QPS system of RQTs circuits. The possible improvements for 2012 will then be discussed together with the foreseen software changes for the orbit reference management.

KoralQuery -- A General Corpus Query Protocol

DEFF Research Database (Denmark)

Bingel, Joachim; Diewald, Nils

2015-01-01

. In this paper, we present KoralQuery, a JSON-LD based general corpus query protocol, aiming to be independent of particular QLs, tasks and corpus formats. In addition to describing the system of types and operations that KoralQuery is built on, we exemplify the representation of corpus queries in the serialized...

How Good Are Query Optimizers, Really?

NARCIS (Netherlands)

Leis, Viktor; Gubichev, Andrey; Mirchev, Atanas; Boncz, Peter; Kemper, Alfons; Neumann, Thomas

2016-01-01

Finding a good join order is crucial for query performance. In this paper, we introduce the Join Order Benchmark (JOB) and experimentally revisit the main components in the classic query optimizer architecture using a complex, real-world data set and realistic multi-join queries. We investigate the

SeqWare Query Engine: storing and searching sequence data in the cloud

Directory of Open Access Journals (Sweden)

Merriman Barry

2010-12-01

Full Text Available Abstract Background Since the introduction of next-generation DNA sequencers the rapid increase in sequencer throughput, and associated drop in costs, has resulted in more than a dozen human genomes being resequenced over the last few years. These efforts are merely a prelude for a future in which genome resequencing will be commonplace for both biomedical research and clinical applications. The dramatic increase in sequencer output strains all facets of computational infrastructure, especially databases and query interfaces. The advent of cloud computing, and a variety of powerful tools designed to process petascale datasets, provide a compelling solution to these ever increasing demands. Results In this work, we present the SeqWare Query Engine which has been created using modern cloud computing technologies and designed to support databasing information from thousands of genomes. Our backend implementation was built using the highly scalable, NoSQL HBase database from the Hadoop project. We also created a web-based frontend that provides both a programmatic and interactive query interface and integrates with widely used genome browsers and tools. Using the query engine, users can load and query variants (SNVs, indels, translocations, etc with a rich level of annotations including coverage and functional consequences. As a proof of concept we loaded several whole genome datasets including the U87MG cell line. We also used a glioblastoma multiforme tumor/normal pair to both profile performance and provide an example of using the Hadoop MapReduce framework within the query engine. This software is open source and freely available from the SeqWare project (http://seqware.sourceforge.net. Conclusions The SeqWare Query Engine provided an easy way to make the U87MG genome accessible to programmers and non-programmers alike. This enabled a faster and more open exploration of results, quicker tuning of parameters for heuristic variant calling filters

SeqWare Query Engine: storing and searching sequence data in the cloud

Science.gov (United States)

2010-01-01

Background Since the introduction of next-generation DNA sequencers the rapid increase in sequencer throughput, and associated drop in costs, has resulted in more than a dozen human genomes being resequenced over the last few years. These efforts are merely a prelude for a future in which genome resequencing will be commonplace for both biomedical research and clinical applications. The dramatic increase in sequencer output strains all facets of computational infrastructure, especially databases and query interfaces. The advent of cloud computing, and a variety of powerful tools designed to process petascale datasets, provide a compelling solution to these ever increasing demands. Results In this work, we present the SeqWare Query Engine which has been created using modern cloud computing technologies and designed to support databasing information from thousands of genomes. Our backend implementation was built using the highly scalable, NoSQL HBase database from the Hadoop project. We also created a web-based frontend that provides both a programmatic and interactive query interface and integrates with widely used genome browsers and tools. Using the query engine, users can load and query variants (SNVs, indels, translocations, etc) with a rich level of annotations including coverage and functional consequences. As a proof of concept we loaded several whole genome datasets including the U87MG cell line. We also used a glioblastoma multiforme tumor/normal pair to both profile performance and provide an example of using the Hadoop MapReduce framework within the query engine. This software is open source and freely available from the SeqWare project (http://seqware.sourceforge.net). Conclusions The SeqWare Query Engine provided an easy way to make the U87MG genome accessible to programmers and non-programmers alike. This enabled a faster and more open exploration of results, quicker tuning of parameters for heuristic variant calling filters, and a common data

SeqWare Query Engine: storing and searching sequence data in the cloud.

Science.gov (United States)

O'Connor, Brian D; Merriman, Barry; Nelson, Stanley F

2010-12-21

Since the introduction of next-generation DNA sequencers the rapid increase in sequencer throughput, and associated drop in costs, has resulted in more than a dozen human genomes being resequenced over the last few years. These efforts are merely a prelude for a future in which genome resequencing will be commonplace for both biomedical research and clinical applications. The dramatic increase in sequencer output strains all facets of computational infrastructure, especially databases and query interfaces. The advent of cloud computing, and a variety of powerful tools designed to process petascale datasets, provide a compelling solution to these ever increasing demands. In this work, we present the SeqWare Query Engine which has been created using modern cloud computing technologies and designed to support databasing information from thousands of genomes. Our backend implementation was built using the highly scalable, NoSQL HBase database from the Hadoop project. We also created a web-based frontend that provides both a programmatic and interactive query interface and integrates with widely used genome browsers and tools. Using the query engine, users can load and query variants (SNVs, indels, translocations, etc) with a rich level of annotations including coverage and functional consequences. As a proof of concept we loaded several whole genome datasets including the U87MG cell line. We also used a glioblastoma multiforme tumor/normal pair to both profile performance and provide an example of using the Hadoop MapReduce framework within the query engine. This software is open source and freely available from the SeqWare project (http://seqware.sourceforge.net). The SeqWare Query Engine provided an easy way to make the U87MG genome accessible to programmers and non-programmers alike. This enabled a faster and more open exploration of results, quicker tuning of parameters for heuristic variant calling filters, and a common data interface to simplify development of

A natural language interface plug-in for cooperative query answering in biological databases.

Science.gov (United States)

Jamil, Hasan M

2012-06-11

One of the many unique features of biological databases is that the mere existence of a ground data item is not always a precondition for a query response. It may be argued that from a biologist's standpoint, queries are not always best posed using a structured language. By this we mean that approximate and flexible responses to natural language like queries are well suited for this domain. This is partly due to biologists' tendency to seek simpler interfaces and partly due to the fact that questions in biology involve high level concepts that are open to interpretations computed using sophisticated tools. In such highly interpretive environments, rigidly structured databases do not always perform well. In this paper, our goal is to propose a semantic correspondence plug-in to aid natural language query processing over arbitrary biological database schema with an aim to providing cooperative responses to queries tailored to users' interpretations. Natural language interfaces for databases are generally effective when they are tuned to the underlying database schema and its semantics. Therefore, changes in database schema become impossible to support, or a substantial reorganization cost must be absorbed to reflect any change. We leverage developments in natural language parsing, rule languages and ontologies, and data integration technologies to assemble a prototype query processor that is able to transform a natural language query into a semantically equivalent structured query over the database. We allow knowledge rules and their frequent modifications as part of the underlying database schema. The approach we adopt in our plug-in overcomes some of the serious limitations of many contemporary natural language interfaces, including support for schema modifications and independence from underlying database schema. The plug-in introduced in this paper is generic and facilitates connecting user selected natural language interfaces to arbitrary databases using a

SPARK: Adapting Keyword Query to Semantic Search

Science.gov (United States)

Zhou, Qi; Wang, Chong; Xiong, Miao; Wang, Haofen; Yu, Yong

Semantic search promises to provide more accurate result than present-day keyword search. However, progress with semantic search has been delayed due to the complexity of its query languages. In this paper, we explore a novel approach of adapting keywords to querying the semantic web: the approach automatically translates keyword queries into formal logic queries so that end users can use familiar keywords to perform semantic search. A prototype system named 'SPARK' has been implemented in light of this approach. Given a keyword query, SPARK outputs a ranked list of SPARQL queries as the translation result. The translation in SPARK consists of three major steps: term mapping, query graph construction and query ranking. Specifically, a probabilistic query ranking model is proposed to select the most likely SPARQL query. In the experiment, SPARK achieved an encouraging translation result.

SPARQL Query Re-writing Using Partonomy Based Transformation Rules

Science.gov (United States)

Jain, Prateek; Yeh, Peter Z.; Verma, Kunal; Henson, Cory A.; Sheth, Amit P.

Often the information present in a spatial knowledge base is represented at a different level of granularity and abstraction than the query constraints. For querying ontology's containing spatial information, the precise relationships between spatial entities has to be specified in the basic graph pattern of SPARQL query which can result in long and complex queries. We present a novel approach to help users intuitively write SPARQL queries to query spatial data, rather than relying on knowledge of the ontology structure. Our framework re-writes queries, using transformation rules to exploit part-whole relations between geographical entities to address the mismatches between query constraints and knowledge base. Our experiments were performed on completely third party datasets and queries. Evaluations were performed on Geonames dataset using questions from National Geographic Bee serialized into SPARQL and British Administrative Geography Ontology using questions from a popular trivia website. These experiments demonstrate high precision in retrieval of results and ease in writing queries.

Adding Query Privacy to Robust DHTs

DEFF Research Database (Denmark)

Backes, Michael; Goldberg, Ian; Kate, Aniket

2011-01-01

intermediate peers that (help to) route the queries towards their destinations. In this paper, we satisfy this requirement by presenting an approach for providing privacy for the keys in DHT queries. We use the concept of oblivious transfer (OT) in communication over DHTs to preserve query privacy without...... of obtaining query privacy over robust DHTs. Finally, we compare the performance of our privacy-preserving protocols with their more privacy-invasive counterparts. We observe that there is no increase in the message complexity and only a small overhead in the computational complexity....

[Laser Tuning Performance Testing and Optimization in TDLAS Oxygen Measuring Systems].

Science.gov (United States)

He, Jun-feng; Hu, Jun; Kan, Rui-feng; Xu, Zhen-yu; Wang, Tao

2015-03-01

TDLAS (tunable diode laser absorption spectroscopy) technology, with its unmatched advantages such as high selectivity molecular spectra, fast response, high sensitivity, non-contact measuring, become the preferred scheme for combustion process diagnosis, and can be effectively used for oxygen measuring. DFB (distributed feedback) laser diode with its small size, low power consumption, long service life, narrow linewidth, tunable wavelength has become the main choice of the TDLAS system. Performance of laser tuning characteristics is a key factor restricting TDLAS's measuring performance. According to TDLAS oxygen measuring system's working requirements, a simple experimental method was used to test and analyze tuning characteristics such as wavelength current, power current and wavelength temperature of a 764 nm DFB laser diode in the system. Nonlinear distortion of tuning curves was obvious, which affects oxygen measuring accuracy. The laser spectra's characteristics such as narrow linewidth, high side mode suppression ratio and wide wavelength tuning range are obvious, while its wavelength-current tuning curve with a tuning rate of about 0.023 nm x mA(-1) is not strictly linear. The higher the temperature the greater the threshold current, the PI curve is not strictly linear either. Temperature tuning curve is of good linearity, temperature-wave-length tuning rate keeps constant of about 0.056 nm/DEG C. Temperature tuning nonlinearity can be improved by high temperature control accuracy, and current power nonlinearity can be improved by setting the reference light path. In order to solve the wavelength current tuning nonlinear problems, the method of DA controlling injection current was considered to compensate for non-linear wavelength current tuning according to DFB laser diode tuning mechanism and polynomial fitting of test results. In view of different type of lasers, this method needs only one polynomial fitting process before the system's initial work. The

Secure Skyline Queries on Cloud Platform.

Science.gov (United States)

Liu, Jinfei; Yang, Juncheng; Xiong, Li; Pei, Jian

2017-04-01

Outsourcing data and computation to cloud server provides a cost-effective way to support large scale data storage and query processing. However, due to security and privacy concerns, sensitive data (e.g., medical records) need to be protected from the cloud server and other unauthorized users. One approach is to outsource encrypted data to the cloud server and have the cloud server perform query processing on the encrypted data only. It remains a challenging task to support various queries over encrypted data in a secure and efficient way such that the cloud server does not gain any knowledge about the data, query, and query result. In this paper, we study the problem of secure skyline queries over encrypted data. The skyline query is particularly important for multi-criteria decision making but also presents significant challenges due to its complex computations. We propose a fully secure skyline query protocol on data encrypted using semantically-secure encryption. As a key subroutine, we present a new secure dominance protocol, which can be also used as a building block for other queries. Finally, we provide both serial and parallelized implementations and empirically study the protocols in terms of efficiency and scalability under different parameter settings, verifying the feasibility of our proposed solutions.

Adding query privacy to robust DHTs

DEFF Research Database (Denmark)

Backes, Michael; Goldberg, Ian; Kate, Aniket

2012-01-01

intermediate peers that (help to) route the queries towards their destinations. In this paper, we satisfy this requirement by presenting an approach for providing privacy for the keys in DHT queries. We use the concept of oblivious transfer (OT) in communication over DHTs to preserve query privacy without...... privacy over robust DHTs. Finally, we compare the performance of our privacy-preserving protocols with their more privacy-invasive counterparts. We observe that there is no increase in the message complexity...

Pareto-depth for multiple-query image retrieval.

Science.gov (United States)

Hsiao, Ko-Jen; Calder, Jeff; Hero, Alfred O

2015-02-01

Most content-based image retrieval systems consider either one single query, or multiple queries that include the same object or represent the same semantic information. In this paper, we consider the content-based image retrieval problem for multiple query images corresponding to different image semantics. We propose a novel multiple-query information retrieval algorithm that combines the Pareto front method with efficient manifold ranking. We show that our proposed algorithm outperforms state of the art multiple-query retrieval algorithms on real-world image databases. We attribute this performance improvement to concavity properties of the Pareto fronts, and prove a theoretical result that characterizes the asymptotic concavity of the fronts.

Performance Tuning of x86 OpenMP Codes with MAQAO

Science.gov (United States)

Barthou, Denis; Charif Rubial, Andres; Jalby, William; Koliai, Souad; Valensi, Cédric

Failing to find the best optimization sequence for a given application code can lead to compiler generated codes with poor performances or inappropriate code. It is necessary to analyze performances from the assembly generated code to improve over the compilation process. This paper presents a tool for the performance analysis of multithreaded codes (OpenMP programs support at the moment). MAQAO relies on static performance evaluation to identify compiler optimizations and assess performance of loops. It exploits static binary rewriting for reading and instrumenting object files or executables. Static binary instrumentation allows the insertion of probes at instruction level. Memory accesses can be captured to help tune the code, but such traces require to be compressed. MAQAO can analyze the results and provide hints for tuning the code. We show on some examples how this can help users improve their OpenMP applications.

Evaluating XML-Extended OLAP Queries Based on a Physical Algebra

DEFF Research Database (Denmark)

Yin, Xuepeng; Pedersen, Torben Bach

2004-01-01

is desirable. In this paper, we extend previous work on the logical federation of OLAP and XML data sources by presenting a simplified query semantics,a physical query algebra and a robust OLAP-XML query engine.Performance experiments with a prototypical implementation suggest that the performance for OLAP...

RCQ-GA: RDF Chain Query Optimization Using Genetic Algorithms

Science.gov (United States)

Hogenboom, Alexander; Milea, Viorel; Frasincar, Flavius; Kaymak, Uzay

The application of Semantic Web technologies in an Electronic Commerce environment implies a need for good support tools. Fast query engines are needed for efficient querying of large amounts of data, usually represented using RDF. We focus on optimizing a special class of SPARQL queries, the so-called RDF chain queries. For this purpose, we devise a genetic algorithm called RCQ-GA that determines the order in which joins need to be performed for an efficient evaluation of RDF chain queries. The approach is benchmarked against a two-phase optimization algorithm, previously proposed in literature. The more complex a query is, the more RCQ-GA outperforms the benchmark in solution quality, execution time needed, and consistency of solution quality. When the algorithms are constrained by a time limit, the overall performance of RCQ-GA compared to the benchmark further improves.

Evaluating SPARQL queries on massive RDF datasets

KAUST Repository

Al-Harbi, Razen

2015-08-01

Distributed RDF systems partition data across multiple computer nodes. Partitioning is typically based on heuristics that minimize inter-node communication and it is performed in an initial, data pre-processing phase. Therefore, the resulting partitions are static and do not adapt to changes in the query workload; as a result, existing systems are unable to consistently avoid communication for queries that are not favored by the initial data partitioning. Furthermore, for very large RDF knowledge bases, the partitioning phase becomes prohibitively expensive, leading to high startup costs. In this paper, we propose AdHash, a distributed RDF system which addresses the shortcomings of previous work. First, AdHash initially applies lightweight hash partitioning, which drastically minimizes the startup cost, while favoring the parallel processing of join patterns on subjects, without any data communication. Using a locality-aware planner, queries that cannot be processed in parallel are evaluated with minimal communication. Second, AdHash monitors the data access patterns and adapts dynamically to the query load by incrementally redistributing and replicating frequently accessed data. As a result, the communication cost for future queries is drastically reduced or even eliminated. Our experiments with synthetic and real data verify that AdHash (i) starts faster than all existing systems, (ii) processes thousands of queries before other systems become online, and (iii) gracefully adapts to the query load, being able to evaluate queries on billion-scale RDF data in sub-seconds. In this demonstration, audience can use a graphical interface of AdHash to verify its performance superiority compared to state-of-the-art distributed RDF systems.

CAPES: Unsupervised Storage Performance Tuning Using Neural Network-Based Deep Reinforcement Learning

CERN Multimedia

CERN. Geneva

2017-01-01

Parameter tuning is an important task of storage performance optimization. Current practice usually involves numerous tweak-benchmark cycles that are slow and costly. To address this issue, we developed CAPES, a model-less deep reinforcement learning-based unsupervised parameter tuning system driven by a deep neural network (DNN). It is designed to nd the optimal values of tunable parameters in computer systems, from a simple client-server system to a large data center, where human tuning can be costly and often cannot achieve optimal performance. CAPES takes periodic measurements of a target computer system’s state, and trains a DNN which uses Q-learning to suggest changes to the system’s current parameter values. CAPES is minimally intrusive, and can be deployed into a production system to collect training data and suggest tuning actions during the system’s daily operation. Evaluation of a prototype on a Lustre system demonstrates an increase in I/O throughput up to 45% at saturation point. About the...

GeoSpark SQL: An Effective Framework Enabling Spatial Queries on Spark

Directory of Open Access Journals (Sweden)

Zhou Huang

2017-09-01

Full Text Available In the era of big data, Internet-based geospatial information services such as various LBS apps are deployed everywhere, followed by an increasing number of queries against the massive spatial data. As a result, the traditional relational spatial database (e.g., PostgreSQL with PostGIS and Oracle Spatial cannot adapt well to the needs of large-scale spatial query processing. Spark is an emerging outstanding distributed computing framework in the Hadoop ecosystem. This paper aims to address the increasingly large-scale spatial query-processing requirement in the era of big data, and proposes an effective framework GeoSpark SQL, which enables spatial queries on Spark. On the one hand, GeoSpark SQL provides a convenient SQL interface; on the other hand, GeoSpark SQL achieves both efficient storage management and high-performance parallel computing through integrating Hive and Spark. In this study, the following key issues are discussed and addressed: (1 storage management methods under the GeoSpark SQL framework, (2 the spatial operator implementation approach in the Spark environment, and (3 spatial query optimization methods under Spark. Experimental evaluation is also performed and the results show that GeoSpark SQL is able to achieve real-time query processing. It should be noted that Spark is not a panacea. It is observed that the traditional spatial database PostGIS/PostgreSQL performs better than GeoSpark SQL in some query scenarios, especially for the spatial queries with high selectivity, such as the point query and the window query. In general, GeoSpark SQL performs better when dealing with compute-intensive spatial queries such as the kNN query and the spatial join query.

Truth Space Method for Caching Database Queries

Directory of Open Access Journals (Sweden)

S. V. Mosin

2015-01-01

Full Text Available We propose a new method of client-side data caching for relational databases with a central server and distant clients. Data are loaded into the client cache based on queries executed on the server. Every query has the corresponding DB table – the result of the query execution. These queries have a special form called "universal relational query" based on three fundamental Relational Algebra operations: selection, projection and natural join. We have to mention that such a form is the closest one to the natural language and the majority of database search queries can be expressed in this way. Besides, this form allows us to analyze query correctness by checking lossless join property. A subsequent query may be executed in a client’s local cache if we can determine that the query result is entirely contained in the cache. For this we compare truth spaces of the logical restrictions in a new user’s query and the results of the queries execution in the cache. Such a comparison can be performed analytically , without need in additional Database queries. This method may be used to define lacking data in the cache and execute the query on the server only for these data. To do this the analytical approach is also used, what distinguishes our paper from the existing technologies. We propose four theorems for testing the required conditions. The first and the third theorems conditions allow us to define the existence of required data in cache. The second and the fourth theorems state conditions to execute queries with cache only. The problem of cache data actualizations is not discussed in this paper. However, it can be solved by cataloging queries on the server and their serving by triggers in background mode. The article is published in the author’s wording.

Query Expansion: Is It Necessary In Textual Case-Based Reasoning ...

African Journals Online (AJOL)

Query expansion (QE) is the process of transforming a seed query to improve retrieval performance in information retrieval operations. It is often intended to overcome a vocabulary mismatch between the query and the document collection. Query expansion is known to improve retrieval effectiveness of some information ...

A Performance Tuning Methodology with Compiler Support

Directory of Open Access Journals (Sweden)

Oscar Hernandez

2008-01-01

Full Text Available We have developed an environment, based upon robust, existing, open source software, for tuning applications written using MPI, OpenMP or both. The goal of this effort, which integrates the OpenUH compiler and several popular performance tools, is to increase user productivity by providing an automated, scalable performance measurement and optimization system. In this paper we describe our environment, show how these complementary tools can work together, and illustrate the synergies possible by exploiting their individual strengths and combined interactions. We also present a methodology for performance tuning that is enabled by this environment. One of the benefits of using compiler technology in this context is that it can direct the performance measurements to capture events at different levels of granularity and help assess their importance, which we have shown to significantly reduce the measurement overheads. The compiler can also help when attempting to understand the performance results: it can supply information on how a code was translated and whether optimizations were applied. Our methodology combines two performance views of the application to find bottlenecks. The first is a high level view that focuses on OpenMP/MPI performance problems such as synchronization cost and load imbalances; the second is a low level view that focuses on hardware counter analysis with derived metrics that assess the efficiency of the code. Our experiments have shown that our approach can significantly reduce overheads for both profiling and tracing to acceptable levels and limit the number of times the application needs to be run with selected hardware counters. In this paper, we demonstrate the workings of this methodology by illustrating its use with selected NAS Parallel Benchmarks and a cloud resolving code.

Spatial Keyword Query Processing

DEFF Research Database (Denmark)

Chen, Lisi; Jensen, Christian S.; Wu, Dingming

2013-01-01

Geo-textual indices play an important role in spatial keyword query- ing. The existing geo-textual indices have not been compared sys- tematically under the same experimental framework. This makes it difficult to determine which indexing technique best supports specific functionality. We provide...... an all-around survey of 12 state- of-the-art geo-textual indices. We propose a benchmark that en- ables the comparison of the spatial keyword query performance. We also report on the findings obtained when applying the bench- mark to the indices, thus uncovering new insights that may guide index...

Location-Dependent Query Processing Under Soft Real-Time Constraints

Directory of Open Access Journals (Sweden)

Zoubir Mammeri

2009-01-01

Full Text Available In recent years, mobile devices and applications achieved an increasing development. In database field, this development required methods to consider new query types like location-dependent queries (i.e. the query results depend on the query issuer location. Although several researches addressed problems related to location-dependent query processing, a few works considered timing requirements that may be associated with queries (i.e., the query results must be delivered to mobile clients on time. The main objective of this paper is to propose a solution for location-dependent query processing under soft real-time constraints. Hence, we propose methods to take into account client location-dependency and to maximize the percentage of queries respecting their deadlines. We validate our proposal by implementing a prototype based on Oracle DBMS. Performance evaluation results show that the proposed solution optimizes the percentage of queries meeting their deadlines and the communication cost.

Evaluating XML-Extended OLAP Queries Based on a Physical Algebra

DEFF Research Database (Denmark)

Yin, Xuepeng; Pedersen, Torben Bach

2006-01-01

. In this paper, we extend previous work on the logical federation of OLAP and XML data sources by presenting a simplified query semantics, a physical query algebra and a robust OLAP-XML query engine as well as the query evaluation techniques. Performance experiments with a prototypical implementation suggest...

PERI auto-tuning

Energy Technology Data Exchange (ETDEWEB)

Bailey, D H; Williams, S [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Chame, J; Chen, C; Hall, M [USC/ISI, Marina del Rey, CA 90292 (United States); Dongarra, J; Moore, S; Seymour, K; You, H [University of Tennessee, Knoxville, TN 37996 (United States); Hollingsworth, J K; Tiwari, A [University of Maryland, College Park, MD 20742 (United States); Hovland, P; Shin, J [Argonne National Laboratory, Argonne, IL 60439 (United States)], E-mail: mhall@isi.edu

2008-07-15

The enormous and growing complexity of today's high-end systems has increased the already significant challenges of obtaining high performance on equally complex scientific applications. Application scientists are faced with a daunting challenge in tuning their codes to exploit performance-enhancing architectural features. The Performance Engineering Research Institute (PERI) is working toward the goal of automating portions of the performance tuning process. This paper describes PERI's overall strategy for auto-tuning tools and recent progress in both building auto-tuning tools and demonstrating their success on kernels, some taken from large-scale applications.

A structural query system for Han characters

DEFF Research Database (Denmark)

Skala, Matthew

2016-01-01

The IDSgrep structural query system for Han character dictionaries is presented. This dictionary search system represents the spatial structure of Han characters using Extended Ideographic Description Sequences (EIDSes), a data model and syntax based on the Unicode IDS concept. It includes a query...... language for EIDS databases, with a freely available implementation and format translation from popular third-party IDS and XML character databases. The system is designed to suit the needs of font developers and foreign language learners. The search algorithm includes a bit vector index inspired by Bloom...... filters to support faster query operations. Experimental results are presented, evaluating the effect of the indexing on query performance....

Approximate dictionary queries

DEFF Research Database (Denmark)

Brodal, Gerth Stølting; Gasieniec, Leszek

1996-01-01

Given a set of n binary strings of length m each. We consider the problem of answering d-queries. Given a binary query string of length m, a d-query is to report if there exists a string in the set within Hamming distance d of . We present a data structure of size O(nm) supporting 1-queries in ti...

A Revisit of Query Expansion with Different Semantic Levels

DEFF Research Database (Denmark)

Zhang, Ce; Cui, Bin; Cong, Gao

2009-01-01

Query expansion has received extensive attention in information retrieval community. Although semantic based query expansion appears to be promising in improving retrieval performance, previous research has shown that it cannot consistently improve retrieval performance. It is a tricky problem to...

A Query Cache Tool for Optimizing Repeatable and Parallel OLAP Queries

Science.gov (United States)

Santos, Ricardo Jorge; Bernardino, Jorge

On-line analytical processing against data warehouse databases is a common form of getting decision making information for almost every business field. Decision support information oftenly concerns periodic values based on regular attributes, such as sales amounts, percentages, most transactioned items, etc. This means that many similar OLAP instructions are periodically repeated, and simultaneously, between the several decision makers. Our Query Cache Tool takes advantage of previously executed queries, storing their results and the current state of the data which was accessed. Future queries only need to execute against the new data, inserted since the queries were last executed, and join these results with the previous ones. This makes query execution much faster, because we only need to process the most recent data. Our tool also minimizes the execution time and resource consumption for similar queries simultaneously executed by different users, putting the most recent ones on hold until the first finish and returns the results for all of them. The stored query results are held until they are considered outdated, then automatically erased. We present an experimental evaluation of our tool using a data warehouse based on a real-world business dataset and use a set of typical decision support queries to discuss the results, showing a very high gain in query execution time.

Integrating user profile in medical CBIR systems to answer perceptual similarity queries

Science.gov (United States)

Bugatti, Pedro H.; Kaster, Daniel S.; Ponciano-Silva, Marcelo; Traina, Agma J. M.; Traina, Caetano, Jr.

2011-03-01

Techniques for Content-Based Image Retrieval (CBIR) have been intensively explored due to the increase in the amount of captured images and the need of fast retrieval of them. The medical field is a specific example that generates a large flow of information, especially digital images employed for diagnosing. One issue that still remains unsolved deals with how to reach the perceptual similarity. That is, to achieve an effective retrieval, one must characterize and quantify the perceptual similarity regarding the specialist in the field. Therefore, the present paper was conceived to fill in this gap creating a consistent support to perform similarity queries over medical images, maintaining the semantics of a given query desired by the user. CBIR systems relying in relevance feedback techniques usually request the users to label relevant images. In this paper, we present a simple but highly effective strategy to survey user profiles, taking advantage of such labeling to implicitly gather the user perceptual similarity. The user profiles maintain the settings desired for each user, allowing tuning the similarity assessment, which encompasses dynamically changing the distance function employed through an interactive process. Experiments using computed tomography lung images show that the proposed approach is effective in capturing the users' perception.

Query responses

Directory of Open Access Journals (Sweden)

Paweł Łupkowski

2017-05-01

Full Text Available In this article we consider the phenomenon of answering a query with a query. Although such answers are common, no large scale, corpus-based characterization exists, with the exception of clarification requests. After briefly reviewing different theoretical approaches on this subject, we present a corpus study of query responses in the British National Corpus and develop a taxonomy for query responses. We point at a variety of response categories that have not been formalized in previous dialogue work, particularly those relevant to adversarial interaction. We show that different response categories have significantly different rates of subsequent answer provision. We provide a formal analysis of the response categories in the framework of KoS.

Recommending Multidimensional Queries

Science.gov (United States)

Giacometti, Arnaud; Marcel, Patrick; Negre, Elsa

Interactive analysis of datacube, in which a user navigates a cube by launching a sequence of queries is often tedious since the user may have no idea of what the forthcoming query should be in his current analysis. To better support this process we propose in this paper to apply a Collaborative Work approach that leverages former explorations of the cube to recommend OLAP queries. The system that we have developed adapts Approximate String Matching, a technique popular in Information Retrieval, to match the current analysis with the former explorations and help suggesting a query to the user. Our approach has been implemented with the open source Mondrian OLAP server to recommend MDX queries and we have carried out some preliminary experiments that show its efficiency for generating effective query recommendations.

Representation and alignment of sung queries for music information retrieval

Science.gov (United States)

Adams, Norman H.; Wakefield, Gregory H.

2005-09-01

The pursuit of robust and rapid query-by-humming systems, which search melodic databases using sung queries, is a common theme in music information retrieval. The retrieval aspect of this database problem has received considerable attention, whereas the front-end processing of sung queries and the data structure to represent melodies has been based on musical intuition and historical momentum. The present work explores three time series representations for sung queries: a sequence of notes, a ``smooth'' pitch contour, and a sequence of pitch histograms. The performance of the three representations is compared using a collection of naturally sung queries. It is found that the most robust performance is achieved by the representation with highest dimension, the smooth pitch contour, but that this representation presents a formidable computational burden. For all three representations, it is necessary to align the query and target in order to achieve robust performance. The computational cost of the alignment is quadratic, hence it is necessary to keep the dimension small for rapid retrieval. Accordingly, iterative deepening is employed to achieve both robust performance and rapid retrieval. Finally, the conventional iterative framework is expanded to adapt the alignment constraints based on previous iterations, further expediting retrieval without degrading performance.

The role of economics in the QUERI program: QUERI Series.

Science.gov (United States)

Smith, Mark W; Barnett, Paul G

2008-04-22

The United States (U.S.) Department of Veterans Affairs (VA) Quality Enhancement Research Initiative (QUERI) has implemented economic analyses in single-site and multi-site clinical trials. To date, no one has reviewed whether the QUERI Centers are taking an optimal approach to doing so. Consistent with the continuous learning culture of the QUERI Program, this paper provides such a reflection. We present a case study of QUERI as an example of how economic considerations can and should be integrated into implementation research within both single and multi-site studies. We review theoretical and applied cost research in implementation studies outside and within VA. We also present a critique of the use of economic research within the QUERI program. Economic evaluation is a key element of implementation research. QUERI has contributed many developments in the field of implementation but has only recently begun multi-site implementation trials across multiple regions within the national VA healthcare system. These trials are unusual in their emphasis on developing detailed costs of implementation, as well as in the use of business case analyses (budget impact analyses). Economics appears to play an important role in QUERI implementation studies, only after implementation has reached the stage of multi-site trials. Economic analysis could better inform the choice of which clinical best practices to implement and the choice of implementation interventions to employ. QUERI economics also would benefit from research on costing methods and development of widely accepted international standards for implementation economics.

Tuning HDF5 subfiling performance on parallel file systems

Energy Technology Data Exchange (ETDEWEB)

Byna, Suren [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Chaarawi, Mohamad [Intel Corp. (United States); Koziol, Quincey [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mainzer, John [The HDF Group (United States); Willmore, Frank [The HDF Group (United States)

2017-05-12

Subfiling is a technique used on parallel file systems to reduce locking and contention issues when multiple compute nodes interact with the same storage target node. Subfiling provides a compromise between the single shared file approach that instigates the lock contention problems on parallel file systems and having one file per process, which results in generating a massive and unmanageable number of files. In this paper, we evaluate and tune the performance of recently implemented subfiling feature in HDF5. In specific, we explain the implementation strategy of subfiling feature in HDF5, provide examples of using the feature, and evaluate and tune parallel I/O performance of this feature with parallel file systems of the Cray XC40 system at NERSC (Cori) that include a burst buffer storage and a Lustre disk-based storage. We also evaluate I/O performance on the Cray XC30 system, Edison, at NERSC. Our results show performance benefits of 1.2X to 6X performance advantage with subfiling compared to writing a single shared HDF5 file. We present our exploration of configurations, such as the number of subfiles and the number of Lustre storage targets to storing files, as optimization parameters to obtain superior I/O performance. Based on this exploration, we discuss recommendations for achieving good I/O performance as well as limitations with using the subfiling feature.

SM4MQ: A Semantic Model for Multidimensional Queries

DEFF Research Database (Denmark)

Varga, Jovan; Dobrokhotova, Ekaterina; Romero, Oscar

2017-01-01

metadata artifacts (e.g., queries) to assist users with the analysis. However, modeling and sharing of most of these artifacts are typically overlooked. Thus, in this paper we focus on the query metadata artifact in the Exploratory OLAP context and propose an RDF-based vocabulary for its representation......, sharing, and reuse on the SW. As OLAP is based on the underlying multidimensional (MD) data model we denote such queries as MD queries and define SM4MQ: A Semantic Model for Multidimensional Queries. Furthermore, we propose a method to automate the exploitation of queries by means of SPARQL. We apply...... the method to a use case of transforming queries from SM4MQ to a vector representation. For the use case, we developed the prototype and performed an evaluation that shows how our approach can significantly ease and support user assistance such as query recommendation....

Evaluating SPARQL queries on massive RDF datasets

KAUST Repository

Al-Harbi, Razen; Abdelaziz, Ibrahim; Kalnis, Panos; Mamoulis, Nikos

2015-01-01

In this paper, we propose AdHash, a distributed RDF system which addresses the shortcomings of previous work. First, AdHash initially applies lightweight hash partitioning, which drastically minimizes the startup cost, while favoring the parallel processing of join patterns on subjects, without any data communication. Using a locality-aware planner, queries that cannot be processed in parallel are evaluated with minimal communication. Second, AdHash monitors the data access patterns and adapts dynamically to the query load by incrementally redistributing and replicating frequently accessed data. As a result, the communication cost for future queries is drastically reduced or even eliminated. Our experiments with synthetic and real data verify that AdHash (i) starts faster than all existing systems, (ii) processes thousands of queries before other systems become online, and (iii) gracefully adapts to the query load, being able to evaluate queries on billion-scale RDF data in sub-seconds. In this demonstration, audience can use a graphical interface of AdHash to verify its performance superiority compared to state-of-the-art distributed RDF systems.

CrossQuery: a web tool for easy associative querying of transcriptome data.

Directory of Open Access Journals (Sweden)

Toni U Wagner

Full Text Available Enormous amounts of data are being generated by modern methods such as transcriptome or exome sequencing and microarray profiling. Primary analyses such as quality control, normalization, statistics and mapping are highly complex and need to be performed by specialists. Thereafter, results are handed back to biomedical researchers, who are then confronted with complicated data lists. For rather simple tasks like data filtering, sorting and cross-association there is a need for new tools which can be used by non-specialists. Here, we describe CrossQuery, a web tool that enables straight forward, simple syntax queries to be executed on transcriptome sequencing and microarray datasets. We provide deep-sequencing data sets of stem cell lines derived from the model fish Medaka and microarray data of human endothelial cells. In the example datasets provided, mRNA expression levels, gene, transcript and sample identification numbers, GO-terms and gene descriptions can be freely correlated, filtered and sorted. Queries can be saved for later reuse and results can be exported to standard formats that allow copy-and-paste to all widespread data visualization tools such as Microsoft Excel. CrossQuery enables researchers to quickly and freely work with transcriptome and microarray data sets requiring only minimal computer skills. Furthermore, CrossQuery allows growing association of multiple datasets as long as at least one common point of correlated information, such as transcript identification numbers or GO-terms, is shared between samples. For advanced users, the object-oriented plug-in and event-driven code design of both server-side and client-side scripts allow easy addition of new features, data sources and data types.

CrossQuery: a web tool for easy associative querying of transcriptome data.

Science.gov (United States)

Wagner, Toni U; Fischer, Andreas; Thoma, Eva C; Schartl, Manfred

2011-01-01

Enormous amounts of data are being generated by modern methods such as transcriptome or exome sequencing and microarray profiling. Primary analyses such as quality control, normalization, statistics and mapping are highly complex and need to be performed by specialists. Thereafter, results are handed back to biomedical researchers, who are then confronted with complicated data lists. For rather simple tasks like data filtering, sorting and cross-association there is a need for new tools which can be used by non-specialists. Here, we describe CrossQuery, a web tool that enables straight forward, simple syntax queries to be executed on transcriptome sequencing and microarray datasets. We provide deep-sequencing data sets of stem cell lines derived from the model fish Medaka and microarray data of human endothelial cells. In the example datasets provided, mRNA expression levels, gene, transcript and sample identification numbers, GO-terms and gene descriptions can be freely correlated, filtered and sorted. Queries can be saved for later reuse and results can be exported to standard formats that allow copy-and-paste to all widespread data visualization tools such as Microsoft Excel. CrossQuery enables researchers to quickly and freely work with transcriptome and microarray data sets requiring only minimal computer skills. Furthermore, CrossQuery allows growing association of multiple datasets as long as at least one common point of correlated information, such as transcript identification numbers or GO-terms, is shared between samples. For advanced users, the object-oriented plug-in and event-driven code design of both server-side and client-side scripts allow easy addition of new features, data sources and data types.

The role of economics in the QUERI program: QUERI Series

Directory of Open Access Journals (Sweden)

Smith Mark W

2008-04-01

Full Text Available Abstract Background The United States (U.S. Department of Veterans Affairs (VA Quality Enhancement Research Initiative (QUERI has implemented economic analyses in single-site and multi-site clinical trials. To date, no one has reviewed whether the QUERI Centers are taking an optimal approach to doing so. Consistent with the continuous learning culture of the QUERI Program, this paper provides such a reflection. Methods We present a case study of QUERI as an example of how economic considerations can and should be integrated into implementation research within both single and multi-site studies. We review theoretical and applied cost research in implementation studies outside and within VA. We also present a critique of the use of economic research within the QUERI program. Results Economic evaluation is a key element of implementation research. QUERI has contributed many developments in the field of implementation but has only recently begun multi-site implementation trials across multiple regions within the national VA healthcare system. These trials are unusual in their emphasis on developing detailed costs of implementation, as well as in the use of business case analyses (budget impact analyses. Conclusion Economics appears to play an important role in QUERI implementation studies, only after implementation has reached the stage of multi-site trials. Economic analysis could better inform the choice of which clinical best practices to implement and the choice of implementation interventions to employ. QUERI economics also would benefit from research on costing methods and development of widely accepted international standards for implementation economics.

Memory aware query scheduling in a database cluster

NARCIS (Netherlands)

F. Waas; M.L. Kersten (Martin)

2000-01-01

textabstractQuery throughput is one of the primary optimization goals in interactive web-based information systems in order to achieve the performance necessary to serve large user communities. Queries in this application domain differ significantly from those in traditional database applications:

In-context query reformulation for failing SPARQL queries

Science.gov (United States)

Viswanathan, Amar; Michaelis, James R.; Cassidy, Taylor; de Mel, Geeth; Hendler, James

2017-05-01

Knowledge bases for decision support systems are growing increasingly complex, through continued advances in data ingest and management approaches. However, humans do not possess the cognitive capabilities to retain a bird's-eyeview of such knowledge bases, and may end up issuing unsatisfiable queries to such systems. This work focuses on the implementation of a query reformulation approach for graph-based knowledge bases, specifically designed to support the Resource Description Framework (RDF). The reformulation approach presented is instance-and schema-aware. Thus, in contrast to relaxation techniques found in the state-of-the-art, the presented approach produces in-context query reformulation.

Google BigQuery analytics

CERN Document Server

Tigani, Jordan

2014-01-01

How to effectively use BigQuery, avoid common mistakes, and execute sophisticated queries against large datasets Google BigQuery Analytics is the perfect guide for business and data analysts who want the latest tips on running complex queries and writing code to communicate with the BigQuery API. The book uses real-world examples to demonstrate current best practices and techniques, and also explains and demonstrates streaming ingestion, transformation via Hadoop in Google Compute engine, AppEngine datastore integration, and using GViz with Tableau to generate charts of query results. In addit

Path-based Queries on Trajectory Data

DEFF Research Database (Denmark)

Krogh, Benjamin Bjerre; Pelekis, Nikos; Theodoridis, Yannis

2014-01-01

In traffic research, management, and planning a number of path-based analyses are heavily used, e.g., for computing turn-times, evaluating green waves, or studying traffic flow. These analyses require retrieving the trajectories that follow the full path being analyzed. Existing path queries cannot...... sufficiently support such path-based analyses because they retrieve all trajectories that touch any edge in the path. In this paper, we define and formalize the strict path query. This is a novel query type tailored to support path-based analysis, where trajectories must follow all edges in the path...... a specific path by only retrieving data from the first and last edge in the path. To correctly answer strict path queries existing network-constrained trajectory indexes must retrieve data from all edges in the path. An extensive performance study of NETTRA using a very large real-world trajectory data set...

Query optimization over crowdsourced data

KAUST Repository

Park, Hyunjung

2013-08-26

Deco is a comprehensive system for answering declarative queries posed over stored relational data together with data obtained on-demand from the crowd. In this paper we describe Deco\\'s cost-based query optimizer, building on Deco\\'s data model, query language, and query execution engine presented earlier. Deco\\'s objective in query optimization is to find the best query plan to answer a query, in terms of estimated monetary cost. Deco\\'s query semantics and plan execution strategies require several fundamental changes to traditional query optimization. Novel techniques incorporated into Deco\\'s query optimizer include a cost model distinguishing between "free" existing data versus paid new data, a cardinality estimation algorithm coping with changes to the database state during query execution, and a plan enumeration algorithm maximizing reuse of common subplans in a setting that makes reuse challenging. We experimentally evaluate Deco\\'s query optimizer, focusing on the accuracy of cost estimation and the efficiency of plan enumeration.

Performance evaluation of unified medical language system®'s synonyms expansion to query PubMed

Directory of Open Access Journals (Sweden)

Griffon Nicolas

2012-02-01

Full Text Available Abstract Background PubMed is the main access to medical literature on the Internet. In order to enhance the performance of its information retrieval tools, primarily non-indexed citations, the authors propose a method: expanding users' queries using Unified Medical Language System' (UMLS synonyms i.e. all the terms gathered under one unique Concept Unique Identifier. Methods This method was evaluated using queries constructed to emphasize the differences between this new method and the current PubMed automatic term mapping. Four experts assessed citation relevance. Results Using UMLS, we were able to retrieve new citations in 45.5% of queries, which implies a small increase in recall. The new strategy led to a heterogeneous 23.7% mean increase in non-indexed citation retrieved. Of these, 82% have been published less than 4 months earlier. The overall mean precision was 48.4% but differed according to the evaluators, ranging from 36.7% to 88.1% (Inter rater agreement was poor: kappa = 0.34. Conclusions This study highlights the need for specific search tools for each type of user and use-cases. The proposed strategy may be useful to retrieve recent scientific advancement.

Enabling Incremental Query Re-Optimization.

Science.gov (United States)

Liu, Mengmeng; Ives, Zachary G; Loo, Boon Thau

2016-01-01

As declarative query processing techniques expand to the Web, data streams, network routers, and cloud platforms, there is an increasing need to re-plan execution in the presence of unanticipated performance changes. New runtime information may affect which query plan we prefer to run. Adaptive techniques require innovation both in terms of the algorithms used to estimate costs , and in terms of the search algorithm that finds the best plan. We investigate how to build a cost-based optimizer that recomputes the optimal plan incrementally given new cost information, much as a stream engine constantly updates its outputs given new data. Our implementation especially shows benefits for stream processing workloads. It lays the foundations upon which a variety of novel adaptive optimization algorithms can be built. We start by leveraging the recently proposed approach of formulating query plan enumeration as a set of recursive datalog queries ; we develop a variety of novel optimization approaches to ensure effective pruning in both static and incremental cases. We further show that the lessons learned in the declarative implementation can be equally applied to more traditional optimizer implementations.

Practical tuning for Oracle

International Nuclear Information System (INIS)

Kwon, Sun Yong

2005-02-01

This book deals with tuning for oracle application, which consists of twenty two chapters. These are the contents of this book : what is tuning?, procedure of tuning, collection of performance data using stats pack, collection of performance data in real time, disk IO dispersion, architecture on Index, partition and IOT, optimization of cluster Factor, optimizer, analysis on plan of operation, selection of Index, tuning of Index, parallel processing architecture, DML, analytic function join method, join type, analysis of application, Lock architecture, SGA architecture and wait event and segment tuning.

A Streams-Based Framework for Defining Location-Based Queries

DEFF Research Database (Denmark)

Jensen, Christian Søndergaard; Xuegang, Huang

2007-01-01

n infrastructure is emerging that supports the delivery of on-line, location-enabled services to mobile users. Such services involve novel database queries, and the database research community is quite active in proposing techniques for the efficient processing of such queries. In parallel to this......, the management of data streams has become an active area of research. While most research in mobile services concerns performance issues, this paper aims to establish a formal framework for defining the semantics of queries encountered in mobile services, most notably the so-called continuous queries...... that are particularly relevant in this context. Rather than inventing an entirely new framework, the paper proposes a framework that builds on concepts from data streams and temporal databases. Definitions of example queries demonstrates how the framework enables clear formulation of query semantics and the comparison...

Collective spatial keyword querying

DEFF Research Database (Denmark)

Cao, Xin; Cong, Gao; Jensen, Christian S.

2011-01-01

With the proliferation of geo-positioning and geo-tagging, spatial web objects that possess both a geographical location and a textual description are gaining in prevalence, and spatial keyword queries that exploit both location and textual description are gaining in prominence. However, the quer......With the proliferation of geo-positioning and geo-tagging, spatial web objects that possess both a geographical location and a textual description are gaining in prevalence, and spatial keyword queries that exploit both location and textual description are gaining in prominence. However......, the queries studied so far generally focus on finding individual objects that each satisfy a query rather than finding groups of objects where the objects in a group collectively satisfy a query. We define the problem of retrieving a group of spatial web objects such that the group's keywords cover the query......'s keywords and such that objects are nearest to the query location and have the lowest inter-object distances. Specifically, we study two variants of this problem, both of which are NP-complete. We devise exact solutions as well as approximate solutions with provable approximation bounds to the problems. We...

Querying Workflow Logs

Directory of Open Access Journals (Sweden)

Yan Tang

2018-01-01

Full Text Available A business process or workflow is an assembly of tasks that accomplishes a business goal. Business process management is the study of the design, configuration/implementation, enactment and monitoring, analysis, and re-design of workflows. The traditional methodology for the re-design and improvement of workflows relies on the well-known sequence of extract, transform, and load (ETL, data/process warehousing, and online analytical processing (OLAP tools. In this paper, we study the ad hoc queryiny of process enactments for (data-centric business processes, bypassing the traditional methodology for more flexibility in querying. We develop an algebraic query language based on “incident patterns” with four operators inspired from Business Process Model and Notation (BPMN representation, allowing the user to formulate ad hoc queries directly over workflow logs. A formal semantics of this query language, a preliminary query evaluation algorithm, and a group of elementary properties of the operators are provided.

In-route skyline querying for location-based services

DEFF Research Database (Denmark)

Xuegang, Huang; Jensen, Kristian S.

2005-01-01

With the emergence of an infrastructure for location-aware mobile services, the processing of advanced, location-based queries that are expected to underlie such services is gaining in relevance, While much work has assumed that users move in Euclidean space, this paper assumes that movement...... their efficient computation. The queries take into account several spatial preferences. and they intuitively return a set of most interesting results for each result returned by the corresponding non-skyline queries. The paper also covers a performance study of the proposed techniques based on real point...

A framework for query optimization to support data mining

NARCIS (Netherlands)

S.R. Choenni (Sunil); A.P.J.M. Siebes (Arno)

1996-01-01

textabstractIn order to extract knowledge from databases, data mining algorithms heavily query the databases. Inefficient processing of these queries will inevitably have its impact on the performance of these algorithms, making them less valuable. In this paper, we describe an optimization

jQuery Pocket Reference

CERN Document Server

Flanagan, David

2010-01-01

"As someone who uses jQuery on a regular basis, it was surprising to discover how much of the library I'm not using. This book is indispensable for anyone who is serious about using jQuery for non-trivial applications."-- Raffaele Cecco, longtime developer of video games, including Cybernoid, Exolon, and Stormlord jQuery is the "write less, do more" JavaScript library. Its powerful features and ease of use have made it the most popular client-side JavaScript framework for the Web. This book is jQuery's trusty companion: the definitive "read less, learn more" guide to the library. jQuery P

jQuery UI cookbook

CERN Document Server

Boduch, Adam

2013-01-01

Filled with a practical collection of recipes, jQuery UI Cookbook is full of clear, step-by-step instructions that will help you harness the powerful UI framework in jQuery. Depending on your needs, you can dip in and out of the Cookbook and its recipes, or follow the book from start to finish.If you are a jQuery UI developer looking to improve your existing applications, extract ideas for your new application, or to better understand the overall widget architecture, then jQuery UI Cookbook is a must-have for you. The reader should at least have a rudimentary understanding of what jQuery UI is

A distributed query execution engine of big attributed graphs.

Science.gov (United States)

Batarfi, Omar; Elshawi, Radwa; Fayoumi, Ayman; Barnawi, Ahmed; Sakr, Sherif

2016-01-01

A graph is a popular data model that has become pervasively used for modeling structural relationships between objects. In practice, in many real-world graphs, the graph vertices and edges need to be associated with descriptive attributes. Such type of graphs are referred to as attributed graphs. G-SPARQL has been proposed as an expressive language, with a centralized execution engine, for querying attributed graphs. G-SPARQL supports various types of graph querying operations including reachability, pattern matching and shortest path where any G-SPARQL query may include value-based predicates on the descriptive information (attributes) of the graph edges/vertices in addition to the structural predicates. In general, a main limitation of centralized systems is that their vertical scalability is always restricted by the physical limits of computer systems. This article describes the design, implementation in addition to the performance evaluation of DG-SPARQL, a distributed, hybrid and adaptive parallel execution engine of G-SPARQL queries. In this engine, the topology of the graph is distributed over the main memory of the underlying nodes while the graph data are maintained in a relational store which is replicated on the disk of each of the underlying nodes. DG-SPARQL evaluates parts of the query plan via SQL queries which are pushed to the underlying relational stores while other parts of the query plan, as necessary, are evaluated via indexless memory-based graph traversal algorithms. Our experimental evaluation shows the efficiency and the scalability of DG-SPARQL on querying massive attributed graph datasets in addition to its ability to outperform the performance of Apache Giraph, a popular distributed graph processing system, by orders of magnitudes.

Research in Mobile Database Query Optimization and Processing

Directory of Open Access Journals (Sweden)

Agustinus Borgy Waluyo

2005-01-01

Full Text Available The emergence of mobile computing provides the ability to access information at any time and place. However, as mobile computing environments have inherent factors like power, storage, asymmetric communication cost, and bandwidth limitations, efficient query processing and minimum query response time are definitely of great interest. This survey groups a variety of query optimization and processing mechanisms in mobile databases into two main categories, namely: (i query processing strategy, and (ii caching management strategy. Query processing includes both pull and push operations (broadcast mechanisms. We further classify push operation into on-demand broadcast and periodic broadcast. Push operation (on-demand broadcast relates to designing techniques that enable the server to accommodate multiple requests so that the request can be processed efficiently. Push operation (periodic broadcast corresponds to data dissemination strategies. In this scheme, several techniques to improve the query performance by broadcasting data to a population of mobile users are described. A caching management strategy defines a number of methods for maintaining cached data items in clients' local storage. This strategy considers critical caching issues such as caching granularity, caching coherence strategy and caching replacement policy. Finally, this survey concludes with several open issues relating to mobile query optimization and processing strategy.

SkyQuery - A Prototype Distributed Query and Cross-Matching Web Service for the Virtual Observatory

Science.gov (United States)

Thakar, A. R.; Budavari, T.; Malik, T.; Szalay, A. S.; Fekete, G.; Nieto-Santisteban, M.; Haridas, V.; Gray, J.

2002-12-01

We have developed a prototype distributed query and cross-matching service for the VO community, called SkyQuery, which is implemented with hierarchichal Web Services. SkyQuery enables astronomers to run combined queries on existing distributed heterogeneous astronomy archives. SkyQuery provides a simple, user-friendly interface to run distributed queries over the federation of registered astronomical archives in the VO. The SkyQuery client connects to the portal Web Service, which farms the query out to the individual archives, which are also Web Services called SkyNodes. The cross-matching algorithm is run recursively on each SkyNode. Each archive is a relational DBMS with a HTM index for fast spatial lookups. The results of the distributed query are returned as an XML DataSet that is automatically rendered by the client. SkyQuery also returns the image cutout corresponding to the query result. SkyQuery finds not only matches between the various catalogs, but also dropouts - objects that exist in some of the catalogs but not in others. This is often as important as finding matches. We demonstrate the utility of SkyQuery with a brown-dwarf search between SDSS and 2MASS, and a search for radio-quiet quasars in SDSS, 2MASS and FIRST. The importance of a service like SkyQuery for the worldwide astronomical community cannot be overstated: data on the same objects in various archives is mapped in different wavelength ranges and looks very different due to different errors, instrument sensitivities and other peculiarities of each archive. Our cross-matching algorithm preforms a fuzzy spatial join across multiple catalogs. This type of cross-matching is currently often done by eye, one object at a time. A static cross-identification table for a set of archives would become obsolete by the time it was built - the exponential growth of astronomical data means that a dynamic cross-identification mechanism like SkyQuery is the only viable option. SkyQuery was funded by a

High-volume image quality assessment systems: tuning performance with an interactive data visualization tool

Science.gov (United States)

Bresnahan, Patricia A.; Pukinskis, Madeleine; Wiggins, Michael

1999-03-01

Image quality assessment systems differ greatly with respect to the number and types of mags they need to evaluate, and their overall architectures. Managers of these systems, however, all need to be able to tune and evaluate system performance, requirements often overlooked or under-designed during project planning. Performance tuning tools allow users to define acceptable quality standards for image features and attributes by adjusting parameter settings. Performance analysis tools allow users to evaluate and/or predict how well a system performs in a given parameter state. While image assessment algorithms are becoming quite sophisticated, duplicating or surpassing the human decision making process in their speed and reliability, they often require a greater investment in 'training' or fine tuning of parameters in order to achieve optimum performance. This process may involve the analysis of hundreds or thousands of images, generating a large database of files and statistics that can be difficult to sort through and interpret. Compounding the difficulty is the fact that personnel charged with tuning and maintaining the production system may not have the statistical or analytical background required for the task. Meanwhile, hardware innovations have greatly increased the volume of images that can be handled in a given time frame, magnifying the consequences of running a production site with an inadequately tuned system. In this paper, some general requirements for a performance evaluation and tuning data visualization system are discussed. A custom engineered solution to the tuning and evaluation problem is then presented, developed within the context of a high volume image quality assessment, data entry, OCR, and image archival system. A key factor influencing the design of the system was the context-dependent definition of image quality, as perceived by a human interpreter. This led to the development of a five-level, hierarchical approach to image quality

The Effect of NUMA Tunings on CPU Performance

Science.gov (United States)

Hollowell, Christopher; Caramarcu, Costin; Strecker-Kellogg, William; Wong, Antonio; Zaytsev, Alexandr

2015-12-01

Non-Uniform Memory Access (NUMA) is a memory architecture for symmetric multiprocessing (SMP) systems where each processor is directly connected to separate memory. Indirect access to other CPU's (remote) RAM is still possible, but such requests are slower as they must also pass through that memory's controlling CPU. In concert with a NUMA-aware operating system, the NUMA hardware architecture can help eliminate the memory performance reductions generally seen in SMP systems when multiple processors simultaneously attempt to access memory. The x86 CPU architecture has supported NUMA for a number of years. Modern operating systems such as Linux support NUMA-aware scheduling, where the OS attempts to schedule a process to the CPU directly attached to the majority of its RAM. In Linux, it is possible to further manually tune the NUMA subsystem using the numactl utility. With the release of Red Hat Enterprise Linux (RHEL) 6.3, the numad daemon became available in this distribution. This daemon monitors a system's NUMA topology and utilization, and automatically makes adjustments to optimize locality. As the number of cores in x86 servers continues to grow, efficient NUMA mappings of processes to CPUs/memory will become increasingly important. This paper gives a brief overview of NUMA, and discusses the effects of manual tunings and numad on the performance of the HEPSPEC06 benchmark, and ATLAS software.

Towards A Streams-Based Framework for Defining Location-Based Queries

DEFF Research Database (Denmark)

Huang, Xuegang; Jensen, Christian S.

2004-01-01

An infrastructure is emerging that supports the delivery of on-line, location-enabled services to mobile users. Such services involve novel database queries, and the database research community is quite active in proposing techniques for the effi- cient processing of such queries. In parallel...... to this, the management of data streams has become an active area of research. While most research in mobile services concerns performance issues, this paper aims to establish a formal framework for defining the semantics of queries encountered in mobile services, most notably the so-called continuous...... queries that are particularly relevant in this context. Rather than inventing an entirely new framework, the paper proposes a framework that builds on concepts from data streams and temporal databases. Definitions of example queries demonstrates how the framework enables clear formulation of query...

Learning semantic query suggestions

NARCIS (Netherlands)

Meij, E.; Bron, M.; Hollink, L.; Huurnink, B.; de Rijke, M.

2009-01-01

An important application of semantic web technology is recognizing human-defined concepts in text. Query transformation is a strategy often used in search engines to derive queries that are able to return more useful search results than the original query and most popular search engines provide

Indexing for summary queries

DEFF Research Database (Denmark)

Yi, Ke; Wang, Lu; Wei, Zhewei

2014-01-01

), of a particular attribute of these records. Aggregation queries are especially useful in business intelligence and data analysis applications where users are interested not in the actual records, but some statistics of them. They can also be executed much more efficiently than reporting queries, by embedding...... returned by reporting queries. In this article, we design indexing techniques that allow for extracting a statistical summary of all the records in the query. The summaries we support include frequent items, quantiles, and various sketches, all of which are of central importance in massive data analysis....... Our indexes require linear space and extract a summary with the optimal or near-optimal query cost. We illustrate the efficiency and usefulness of our designs through extensive experiments and a system demonstration....

Dataflow Query Execution in a Parallel Main-Memory Environment

NARCIS (Netherlands)

Wilschut, A.N.; Apers, Peter M.G.

1991-01-01

The performance and characteristics of the execution of various join-trees on a parallel DBMS are studied. The results are a step in the direction of the design of a query optimization strategy that is fit for parallel execution of complex queries. Among others, synchronization issues are identified

The CMS DBS query language

International Nuclear Information System (INIS)

Kuznetsov, Valentin; Riley, Daniel; Afaq, Anzar; Sekhri, Vijay; Guo Yuyi; Lueking, Lee

2010-01-01

The CMS experiment has implemented a flexible and powerful system enabling users to find data within the CMS physics data catalog. The Dataset Bookkeeping Service (DBS) comprises a database and the services used to store and access metadata related to CMS physics data. To this, we have added a generalized query system in addition to the existing web and programmatic interfaces to the DBS. This query system is based on a query language that hides the complexity of the underlying database structure by discovering the join conditions between database tables. This provides a way of querying the system that is simple and straightforward for CMS data managers and physicists to use without requiring knowledge of the database tables or keys. The DBS Query Language uses the ANTLR tool to build the input query parser and tokenizer, followed by a query builder that uses a graph representation of the DBS schema to construct the SQL query sent to underlying database. We will describe the design of the query system, provide details of the language components and overview of how this component fits into the overall data discovery system architecture.

Performance issues, downtime recovery and tuning in the Next Linear Collider (NLC)

International Nuclear Information System (INIS)

Zimmermann, F.; Adolphsen, C.; Assmann, R.

1997-05-01

The Next Linear Collider (NLC) consists of several large subsystems, each of which must be operational and tuned in order to deliver luminosity. Considering specific examples, we study how the different subsystems respond to various perturbations such as ground motion, temperature changes, drifts of beam-position monitors etc., and we estimate the overall time requirements for tuning and downtime recovery of each subsystem. The succession of subsystem failures and recoveries as well as other performance degradations can be modeled as a Markov process, where each subsystem is characterized, e.g., by its failure rate and recovery time. Such a model allows the prediction of the overall NLC availability. Our mathematical description of a linear collider is benchmarked against the known performance of the Stanford Linear Collider (SLC)

Mastering jQuery mobile

CERN Document Server

Lambert, Chip

2015-01-01

You've started down the path of jQuery Mobile, now begin mastering some of jQuery Mobile's higher level topics. Go beyond jQuery Mobile's documentation and master one of the hottest mobile technologies out there. Previous JavaScript and PHP experience can help you get the most out of this book.

Dataflow Query Execution in a Parallel, Main-memory Environment

NARCIS (Netherlands)

Wilschut, A.N.; Apers, Peter M.G.

In this paper, the performance and characteristics of the execution of various join-trees on a parallel DBMS are studied. The results of this study are a step into the direction of the design of a query optimization strategy that is fit for parallel execution of complex queries. Among others,

User perspectives on query difficulty

DEFF Research Database (Denmark)

Lioma, Christina; Larsen, Birger; Schütze, Hinrich

2011-01-01

be difficult for the system to address? (2) Are users aware of specific features in their query (e.g., domain-specificity, vagueness) that may render their query difficult for an IR system to address? A study of 420 queries from a Web search engine query log that are pre-categorised as easy, medium, hard...

CSRQ: Communication-Efficient Secure Range Queries in Two-Tiered Sensor Networks

Directory of Open Access Journals (Sweden)

Hua Dai

2016-02-01

Full Text Available In recent years, we have seen many applications of secure query in two-tiered wireless sensor networks. Storage nodes are responsible for storing data from nearby sensor nodes and answering queries from Sink. It is critical to protect data security from a compromised storage node. In this paper, the Communication-efficient Secure Range Query (CSRQ—a privacy and integrity preserving range query protocol—is proposed to prevent attackers from gaining information of both data collected by sensor nodes and queries issued by Sink. To preserve privacy and integrity, in addition to employing the encoding mechanisms, a novel data structure called encrypted constraint chain is proposed, which embeds the information of integrity verification. Sink can use this encrypted constraint chain to verify the query result. The performance evaluation shows that CSRQ has lower communication cost than the current range query protocols.

Memory-Aware Query Routing in Interactive Web-based Information Systems

NARCIS (Netherlands)

F. Waas; M.L. Kersten (Martin)

2001-01-01

textabstractQuery throughput is one of the primary optimization goals in interactive web-based information systems in order to achieve the performance necessary to serve large user communities. Queries in this application domain differ significantly from those in traditional database applications:

The Effect of NUMA Tunings on CPU Performance

International Nuclear Information System (INIS)

Hollowell, Christopher; Caramarcu, Costin; Strecker-Kellogg, William; Wong, Antonio; Zaytsev, Alexandr

2015-01-01

Non-Uniform Memory Access (NUMA) is a memory architecture for symmetric multiprocessing (SMP) systems where each processor is directly connected to separate memory. Indirect access to other CPU's (remote) RAM is still possible, but such requests are slower as they must also pass through that memory's controlling CPU. In concert with a NUMA-aware operating system, the NUMA hardware architecture can help eliminate the memory performance reductions generally seen in SMP systems when multiple processors simultaneously attempt to access memory.The x86 CPU architecture has supported NUMA for a number of years. Modern operating systems such as Linux support NUMA-aware scheduling, where the OS attempts to schedule a process to the CPU directly attached to the majority of its RAM. In Linux, it is possible to further manually tune the NUMA subsystem using the numactl utility. With the release of Red Hat Enterprise Linux (RHEL) 6.3, the numad daemon became available in this distribution. This daemon monitors a system's NUMA topology and utilization, and automatically makes adjustments to optimize locality.As the number of cores in x86 servers continues to grow, efficient NUMA mappings of processes to CPUs/memory will become increasingly important. This paper gives a brief overview of NUMA, and discusses the effects of manual tunings and numad on the performance of the HEPSPEC06 benchmark, and ATLAS software. (paper)

Mastering jQuery

CERN Document Server

Libby, Alex

2015-01-01

If you are a developer who is already familiar with using jQuery and wants to push your skill set further, then this book is for you. The book assumes an intermediate knowledge level of jQuery, JavaScript, HTML5, and CSS.

Performance tuning for CUDA-accelerated neighborhood denoising filters

Energy Technology Data Exchange (ETDEWEB)

Zheng, Ziyi; Mueller, Klaus [Stony Brook Univ., NY (United States). Center for Visual Computing, Computer Science; Xu, Wei

2011-07-01

Neighborhood denoising filters are powerful techniques in image processing and can effectively enhance the image quality in CT reconstructions. In this study, by taking the bilateral filter and the non-local mean filter as two examples, we discuss their implementations and perform fine-tuning on the targeted GPU architecture. Experimental results show that the straightforward GPU-based neighborhood filters can be further accelerated by pre-fetching. The optimized GPU-accelerated denoising filters are ready for plug-in into reconstruction framework to enable fast denoising without compromising image quality. (orig.)

Smart Query Answering for Marine Sensor Data

Directory of Open Access Journals (Sweden)

Paulo de Souza

2011-03-01

Full Text Available We review existing query answering systems for sensor data. We then propose an extended query answering approach termed smart query, specifically for marine sensor data. The smart query answering system integrates pattern queries and continuous queries. The proposed smart query system considers both streaming data and historical data from marine sensor networks. The smart query also uses query relaxation technique and semantics from domain knowledge as a recommender system. The proposed smart query benefits in building data and information systems for marine sensor networks.

Smart query answering for marine sensor data.

Science.gov (United States)

Shahriar, Md Sumon; de Souza, Paulo; Timms, Greg

2011-01-01

We review existing query answering systems for sensor data. We then propose an extended query answering approach termed smart query, specifically for marine sensor data. The smart query answering system integrates pattern queries and continuous queries. The proposed smart query system considers both streaming data and historical data from marine sensor networks. The smart query also uses query relaxation technique and semantics from domain knowledge as a recommender system. The proposed smart query benefits in building data and information systems for marine sensor networks.

Advances in nowcasting influenza-like illness rates using search query logs

Science.gov (United States)

Lampos, Vasileios; Miller, Andrew C.; Crossan, Steve; Stefansen, Christian

2015-08-01

User-generated content can assist epidemiological surveillance in the early detection and prevalence estimation of infectious diseases, such as influenza. Google Flu Trends embodies the first public platform for transforming search queries to indications about the current state of flu in various places all over the world. However, the original model significantly mispredicted influenza-like illness rates in the US during the 2012-13 flu season. In this work, we build on the previous modeling attempt, proposing substantial improvements. Firstly, we investigate the performance of a widely used linear regularized regression solver, known as the Elastic Net. Then, we expand on this model by incorporating the queries selected by the Elastic Net into a nonlinear regression framework, based on a composite Gaussian Process. Finally, we augment the query-only predictions with an autoregressive model, injecting prior knowledge about the disease. We assess predictive performance using five consecutive flu seasons spanning from 2008 to 2013 and qualitatively explain certain shortcomings of the previous approach. Our results indicate that a nonlinear query modeling approach delivers the lowest cumulative nowcasting error, and also suggest that query information significantly improves autoregressive inferences, obtaining state-of-the-art performance.

Querying UML models using OCL and Prolog: A performance study

NARCIS (Netherlands)

Chimiak-Opoka, J.; Felderer, M.; Lenz, C.; Lange, C.F.J.

2008-01-01

The size of unified modeling language (UML) models used in practice is very large and ranges up to hundreds and thousands of classes. Querying of these models is used to support their quality assessment by information filtering and aggregating. For both, human cognition and automated analysis, there

Comparing IndexedHBase and Riak for Serving Truthy: Performance of Data Loading and Query Evaluation

Science.gov (United States)

2013-08-01

evaluation We choose one popular meme “#euro2012” within the loaded dataset, as along with a time window whose length varies from 3 hours to 16...IndexedHBase. The “ meme -post-count” query falls into this category. On IndexedHBase, query evaluation can be done by simply going through the rows in meme ...index tables for each meme in the query and counting the number of qualified tweet IDs. In the case of Riak this is accomplished by issuing an HTTP

Query construction, entropy, and generalization in neural-network models

Science.gov (United States)

Sollich, Peter

1994-05-01

We study query construction algorithms, which aim at improving the generalization ability of systems that learn from examples by choosing optimal, nonredundant training sets. We set up a general probabilistic framework for deriving such algorithms from the requirement of optimizing a suitable objective function; specifically, we consider the objective functions entropy (or information gain) and generalization error. For two learning scenarios, the high-low game and the linear perceptron, we evaluate the generalization performance obtained by applying the corresponding query construction algorithms and compare it to training on random examples. We find qualitative differences between the two scenarios due to the different structure of the underlying rules (nonlinear and ``noninvertible'' versus linear); in particular, for the linear perceptron, random examples lead to the same generalization ability as a sequence of queries in the limit of an infinite number of examples. We also investigate learning algorithms which are ill matched to the learning environment and find that, in this case, minimum entropy queries can in fact yield a lower generalization ability than random examples. Finally, we study the efficiency of single queries and its dependence on the learning history, i.e., on whether the previous training examples were generated randomly or by querying, and the difference between globally and locally optimal query construction.

jQuery For Dummies

CERN Document Server

Beighley, Lynn

2010-01-01

Learn how jQuery can make your Web page or blog stand out from the crowd!. jQuery is free, open source software that allows you to extend and customize Joomla!, Drupal, AJAX, and WordPress via plug-ins. Assuming no previous programming experience, Lynn Beighley takes you through the basics of jQuery from the very start. You'll discover how the jQuery library separates itself from other JavaScript libraries through its ease of use, compactness, and friendliness if you're a beginner programmer. Written in the easy-to-understand style of the For Dummies brand, this book demonstrates how you can a

Web development with jQuery

CERN Document Server

York, Richard

2015-01-01

Newly revised and updated resource on jQuery's many features and advantages Web Development with jQuery offers a major update to the popular Beginning JavaScript and CSS Development with jQuery from 2009. More than half of the content is new or updated, and reflects recent innovations with regard to mobile applications, jQuery mobile, and the spectrum of associated plugins. Readers can expect thorough revisions with expanded coverage of events, CSS, AJAX, animation, and drag and drop. New chapters bring developers up to date on popular features like jQuery UI, navigation, tables, interacti

Optimizing Temporal Queries

DEFF Research Database (Denmark)

Toman, David; Bowman, Ivan Thomas

2003-01-01

Recent research in the area of temporal databases has proposed a number of query languages that vary in their expressive power and the semantics they provide to users. These query languages represent a spectrum of solutions to the tension between clean semantics and efficient evaluation. Often, t...

Mathematical Formula Search using Natural Language Queries

Directory of Open Access Journals (Sweden)

YANG, S.

2014-11-01

Full Text Available This paper presents how to search mathematical formulae written in MathML when given plain words as a query. Since the proposed method allows natural language queries like the traditional Information Retrieval for the mathematical formula search, users do not need to enter any complicated math symbols and to use any formula input tool. For this, formula data is converted into plain texts, and features are extracted from the converted texts. In our experiments, we achieve an outstanding performance, a MRR of 0.659. In addition, we introduce how to utilize formula classification for formula search. By using class information, we finally achieve an improved performance, a MRR of 0.690.

Querying Sentiment Development over Time

DEFF Research Database (Denmark)

Andreasen, Troels; Christiansen, Henning; Have, Christian Theil

2013-01-01

A new language is introduced for describing hypotheses about fluctuations of measurable properties in streams of timestamped data, and as prime example, we consider trends of emotions in the constantly flowing stream of Twitter messages. The language, called EmoEpisodes, has a precise semantics...... that measures how well a hypothesis characterizes a given time interval; the semantics is parameterized so it can be adjusted to different views of the data. EmoEpisodes is extended to a query language with variables standing for unknown topics and emotions, and the query-answering mechanism will return...... instantiations for topics and emotions as well as time intervals that provide the largest deflections in this measurement. Experiments are performed on a selection of Twitter data to demonstrates the usefulness of the approach....

jQuery Mobile

CERN Document Server

Reid, Jon

2011-01-01

Native apps have distinct advantages, but the future belongs to mobile web apps that function on a broad range of smartphones and tablets. Get started with jQuery Mobile, the touch-optimized framework for creating apps that look and behave consistently across many devices. This concise book provides HTML5, CSS3, and JavaScript code examples, screen shots, and step-by-step guidance to help you build a complete working app with jQuery Mobile. If you're already familiar with the jQuery JavaScript library, you can use your existing skills to build cross-platform mobile web apps right now. This b

Re-tuning tuned mass dampers using ambient vibration measurements

International Nuclear Information System (INIS)

Hazra, B; Sadhu, A; Narasimhan, S; Lourenco, R

2010-01-01

Deterioration, accidental changes in the operating conditions, or incorrect estimates of the structure modal properties lead to de-tuning in tuned mass dampers (TMDs). To restore optimal performance, it is necessary to estimate the modal properties of the system, and re-tune the TMD to its optimal state. The presence of closely spaced modes and a relatively large amount of damping in the dominant modes renders the process of identification difficult. Furthermore, the process of estimating the modal properties of the bare structure using ambient vibration measurements of the structure with the TMD is challenging. In order to overcome these challenges, a novel identification and re-tuning algorithm is proposed. The process of identification consists of empirical mode decomposition to separate the closely spaced modes, followed by the blind identification of the remaining modes. Algorithms for estimating the fundamental frequency and the mode shape of the primary structure necessary for re-tuning the TMD are proposed. Experimental results from the application of the proposed algorithms to identify and re-tune a laboratory structure TMD system are presented

Secure Nearest Neighbor Query on Crowd-Sensing Data

Directory of Open Access Journals (Sweden)

Ke Cheng

2016-09-01

Full Text Available Nearest neighbor queries are fundamental in location-based services, and secure nearest neighbor queries mainly focus on how to securely and quickly retrieve the nearest neighbor in the outsourced cloud server. However, the previous big data system structure has changed because of the crowd-sensing data. On the one hand, sensing data terminals as the data owner are numerous and mistrustful, while, on the other hand, in most cases, the terminals find it difficult to finish many safety operation due to computation and storage capability constraints. In light of they Multi Owners and Multi Users (MOMU situation in the crowd-sensing data cloud environment, this paper presents a secure nearest neighbor query scheme based on the proxy server architecture, which is constructed by protocols of secure two-party computation and secure Voronoi diagram algorithm. It not only preserves the data confidentiality and query privacy but also effectively resists the collusion between the cloud server and the data owners or users. Finally, extensive theoretical and experimental evaluations are presented to show that our proposed scheme achieves a superior balance between the security and query performance compared to other schemes.

Macromolecular query language (MMQL): prototype data model and implementation.

Science.gov (United States)

Shindyalov, I N; Chang, W; Pu, C; Bourne, P E

1994-11-01

Macromolecular query language (MMQL) is an extensible interpretive language in which to pose questions concerning the experimental or derived features of the 3-D structure of biological macromolecules. MMQL portends to be intuitive with a simple syntax, so that from a user's perspective complex queries are easily written. A number of basic queries and a more complex query--determination of structures containing a five-strand Greek key motif--are presented to illustrate the strengths and weaknesses of the language. The predominant features of MMQL are a filter and pattern grammar which are combined to express a wide range of interesting biological queries. Filters permit the selection of object attributes, for example, compound name and resolution, whereas the patterns currently implemented query primary sequence, close contacts, hydrogen bonding, secondary structure, conformation and amino acid properties (volume, polarity, isoelectric point, hydrophobicity and different forms of exposure). MMQL queries are processed by MMQLlib; a C++ class library, to which new query methods and pattern types are easily added. The prototype implementation described uses PDBlib, another C(++)-based class library from representing the features of biological macromolecules at the level of detail parsable from a PDB file. Since PDBlib can represent data stored in relational and object-oriented databases, as well as PDB files, once these data are loaded they too can be queried by MMQL. Performance metrics are given for queries of PDB files for which all derived data are calculated at run time and compared to a preliminary version of OOPDB, a prototype object-oriented database with a schema based on a persistent version of PDBlib which offers more efficient data access and the potential to maintain derived information. MMQLlib, PDBlib and associated software are available via anonymous ftp from cuhhca.hhmi.columbia.edu.

Inductive queries for a drug designing robot scientist

OpenAIRE

King, Ross D.; Schierz, Amanda; Clare, Amanda; Rowland, Jem; Sparkes, Andrew; Nijssen, Siegfried; Ramon, Jan

2010-01-01

It is increasingly clear that machine learning algorithms need to be integrated in an iterative scientific discovery loop, in which data is queried repeatedly by means of inductive queries and where the computer provides guidance to the experiments that are being performed. In this chapter, we summarise several key challenges in achieving this integration of machine learning and data mining algorithms in methods for the discovery of Quantitative Structure Activity Relationships (QSARs). We in...

An empirical study on SAJQ (Sorting Algorithm for Join Queries

Directory of Open Access Journals (Sweden)

Hassan I. Mathkour

2010-06-01

Full Text Available Most queries that applied on database management systems (DBMS depend heavily on the performance of the used sorting algorithm. In addition to have an efficient sorting algorithm, as a primary feature, stability of such algorithms is a major feature that is needed in performing DBMS queries. In this paper, we study a new Sorting Algorithm for Join Queries (SAJQ that has both advantages of being efficient and stable. The proposed algorithm takes the advantage of using the m-way-merge algorithm in enhancing its time complexity. SAJQ performs the sorting operation in a time complexity of O(nlogm, where n is the length of the input array and m is number of sub-arrays used in sorting. An unsorted input array of length n is arranged into m sorted sub-arrays. The m-way-merge algorithm merges the sorted m sub-arrays into the final output sorted array. The proposed algorithm keeps the stability of the keys intact. An analytical proof has been conducted to prove that, in the worst case, the proposed algorithm has a complexity of O(nlogm. Also, a set of experiments has been performed to investigate the performance of the proposed algorithm. The experimental results have shown that the proposed algorithm outperforms other Stable–Sorting algorithms that are designed for join-based queries.

Towards Hybrid Online On-Demand Querying of Realtime Data with Stateful Complex Event Processing

Energy Technology Data Exchange (ETDEWEB)

Zhou, Qunzhi; Simmhan, Yogesh; Prasanna, Viktor K.

2013-10-09

Emerging Big Data applications in areas like e-commerce and energy industry require both online and on-demand queries to be performed over vast and fast data arriving as streams. These present novel challenges to Big Data management systems. Complex Event Processing (CEP) is recognized as a high performance online query scheme which in particular deals with the velocity aspect of the 3-V’s of Big Data. However, traditional CEP systems do not consider data variety and lack the capability to embed ad hoc queries over the volume of data streams. In this paper, we propose H2O, a stateful complex event processing framework, to support hybrid online and on-demand queries over realtime data. We propose a semantically enriched event and query model to address data variety. A formal query algebra is developed to precisely capture the stateful and containment semantics of online and on-demand queries. We describe techniques to achieve the interactive query processing over realtime data featured by efficient online querying, dynamic stream data persistence and on-demand access. The system architecture is presented and the current implementation status reported.

A Strategy for Automatic Performance Tuning of Stencil Computations on GPUs

Directory of Open Access Journals (Sweden)

Joseph D. Garvey

2018-01-01

Full Text Available We propose and evaluate a novel strategy for tuning the performance of a class of stencil computations on Graphics Processing Units. The strategy uses a machine learning model to predict the optimal way to load data from memory followed by a heuristic that divides other optimizations into groups and exhaustively explores one group at a time. We use a set of 104 synthetic OpenCL stencil benchmarks that are representative of many real stencil computations. We first demonstrate the need for auto-tuning by showing that the optimization space is sufficiently complex that simple approaches to determining a high-performing configuration fail. We then demonstrate the effectiveness of our approach on NVIDIA and AMD GPUs. Relative to a random sampling of the space, we find configurations that are 12%/32% faster on the NVIDIA/AMD platform in 71% and 4% less time, respectively. Relative to an expert search, we achieve 5% and 9% better performance on the two platforms in 89% and 76% less time. We also evaluate our strategy for different stencil computational intensities, varying array sizes and shapes, and in combination with expert search.

Incremental Query Rewriting with Resolution

Science.gov (United States)

Riazanov, Alexandre; Aragão, Marcelo A. T.

We address the problem of semantic querying of relational databases (RDB) modulo knowledge bases using very expressive knowledge representation formalisms, such as full first-order logic or its various fragments. We propose to use a resolution-based first-order logic (FOL) reasoner for computing schematic answers to deductive queries, with the subsequent translation of these schematic answers to SQL queries which are evaluated using a conventional relational DBMS. We call our method incremental query rewriting, because an original semantic query is rewritten into a (potentially infinite) series of SQL queries. In this chapter, we outline the main idea of our technique - using abstractions of databases and constrained clauses for deriving schematic answers, and provide completeness and soundness proofs to justify the applicability of this technique to the case of resolution for FOL without equality. The proposed method can be directly used with regular RDBs, including legacy databases. Moreover, we propose it as a potential basis for an efficient Web-scale semantic search technology.

Range-clustering queries

NARCIS (Netherlands)

Abrahamsen, M.; de Berg, M.T.; Buchin, K.A.; Mehr, M.; Mehrabi, A.D.

2017-01-01

In a geometric k -clustering problem the goal is to partition a set of points in R d into k subsets such that a certain cost function of the clustering is minimized. We present data structures for orthogonal range-clustering queries on a point set S : given a query box Q and an integer k>2 , compute

Driving the Power of AIX Performance Tuning on IBM Power

CERN Document Server

Milberg, Ken

2009-01-01

A concise reference for IT professionals, this book goes beyond the rules and contains the best practices and strategies for solid tuning methodology. Tips based on years of experience from an AIX tuning master show specific steps for monitoring and tuning CPU, virtual memory, disk I/O, and network components. Also offering techniques for tuning Oracle and Linux structures that run on an IBM power system-as well as for the new AIX 6.1-this manual discusses what tools are available, how to best use them to collect historical data, and when to analyze trends and results. The only comprehensive,

Matching health information seekers' queries to medical terms.

Science.gov (United States)

Soualmia, Lina F; Prieur-Gaston, Elise; Moalla, Zied; Lecroq, Thierry; Darmoni, Stéfan J

2012-01-01

The Internet is a major source of health information but most seekers are not familiar with medical vocabularies. Hence, their searches fail due to bad query formulation. Several methods have been proposed to improve information retrieval: query expansion, syntactic and semantic techniques or knowledge-based methods. However, it would be useful to clean those queries which are misspelled. In this paper, we propose a simple yet efficient method in order to correct misspellings of queries submitted by health information seekers to a medical online search tool. In addition to query normalizations and exact phonetic term matching, we tested two approximate string comparators: the similarity score function of Stoilos and the normalized Levenshtein edit distance. We propose here to combine them to increase the number of matched medical terms in French. We first took a sample of query logs to determine the thresholds and processing times. In the second run, at a greater scale we tested different combinations of query normalizations before or after misspelling correction with the retained thresholds in the first run. According to the total number of suggestions (around 163, the number of the first sample of queries), at a threshold comparator score of 0.3, the normalized Levenshtein edit distance gave the highest F-Measure (88.15%) and at a threshold comparator score of 0.7, the Stoilos function gave the highest F-Measure (84.31%). By combining Levenshtein and Stoilos, the highest F-Measure (80.28%) is obtained with 0.2 and 0.7 thresholds respectively. However, queries are composed by several terms that may be combination of medical terms. The process of query normalization and segmentation is thus required. The highest F-Measure (64.18%) is obtained when this process is realized before spelling-correction. Despite the widely known high performance of the normalized edit distance of Levenshtein, we show in this paper that its combination with the Stoilos algorithm improved

Simultaneous gains tuning in boiler/turbine PID-based controller clusters using iterative feedback tuning methodology.

Science.gov (United States)

Zhang, Shu; Taft, Cyrus W; Bentsman, Joseph; Hussey, Aaron; Petrus, Bryan

2012-09-01

Tuning a complex multi-loop PID based control system requires considerable experience. In today's power industry the number of available qualified tuners is dwindling and there is a great need for better tuning tools to maintain and improve the performance of complex multivariable processes. Multi-loop PID tuning is the procedure for the online tuning of a cluster of PID controllers operating in a closed loop with a multivariable process. This paper presents the first application of the simultaneous tuning technique to the multi-input-multi-output (MIMO) PID based nonlinear controller in the power plant control context, with the closed-loop system consisting of a MIMO nonlinear boiler/turbine model and a nonlinear cluster of six PID-type controllers. Although simplified, the dynamics and cross-coupling of the process and the PID cluster are similar to those used in a real power plant. The particular technique selected, iterative feedback tuning (IFT), utilizes the linearized version of the PID cluster for signal conditioning, but the data collection and tuning is carried out on the full nonlinear closed-loop system. Based on the figure of merit for the control system performance, the IFT is shown to deliver performance favorably comparable to that attained through the empirical tuning carried out by an experienced control engineer. Copyright © 2012 ISA. Published by Elsevier Ltd. All rights reserved.

Flattening Queries over Nested Data Types

NARCIS (Netherlands)

van Ruth, J.

2006-01-01

The theory developed in this thesis provides a method to improve the efficiency of querying nested data. The roots of this research lie in the tension between data model expressiveness and performance. Obviously, more expressive data models are more convenient for application programmers. For many

Lost in translation? A multilingual Query Builder improves the quality of PubMed queries: a randomised controlled trial.

Science.gov (United States)

Schuers, Matthieu; Joulakian, Mher; Kerdelhué, Gaetan; Segas, Léa; Grosjean, Julien; Darmoni, Stéfan J; Griffon, Nicolas

2017-07-03

MEDLINE is the most widely used medical bibliographic database in the world. Most of its citations are in English and this can be an obstacle for some researchers to access the information the database contains. We created a multilingual query builder to facilitate access to the PubMed subset using a language other than English. The aim of our study was to assess the impact of this multilingual query builder on the quality of PubMed queries for non-native English speaking physicians and medical researchers. A randomised controlled study was conducted among French speaking general practice residents. We designed a multi-lingual query builder to facilitate information retrieval, based on available MeSH translations and providing users with both an interface and a controlled vocabulary in their own language. Participating residents were randomly allocated either the French or the English version of the query builder. They were asked to translate 12 short medical questions into MeSH queries. The main outcome was the quality of the query. Two librarians blind to the arm independently evaluated each query, using a modified published classification that differentiated eight types of errors. Twenty residents used the French version of the query builder and 22 used the English version. 492 queries were analysed. There were significantly more perfect queries in the French group vs. the English group (respectively 37.9% vs. 17.9%; p PubMed queries in particular for researchers whose first language is not English.

Linking the STCN and Performing Big Data Queries in the Humanities

NARCIS (Netherlands)

Beek, Wouter; Hoekstra, Rinke; Maas, Fernie; Meroño-Peñuela, Albert; Leemans, Inger

2014-01-01

The Short Title Catalogue, Netherlands (STCN) is a retrospective bibliography containing descriptions of over 200.000 Dutch publications from the period 1540-1800. The STCN is compiled by the National Library of the Netherlands. In order to facilitate more complex querying capabilities than is

DSM vs. NSM: CPU Performance Tradeoffs in Block-Oriented Query Processing

NARCIS (Netherlands)

M. Zukowski (Marcin); N.J. Nes (Niels); P.A. Boncz (Peter)

2008-01-01

textabstractComparisons between the merits of row-wise storage (NSM) and columnar storage (DSM) are typically made with respect to the persistent storage layer of database systems. In this paper, however, we focus on the CPU efficiency tradeoffs of tuple representations inside the query

Explicit MPC design and performance-based tuning of an Adaptive Cruise Control Stop-&-Go

NARCIS (Netherlands)

Naus, G.J.L.; Ploeg, J.; Molengraft, M.J.G. van de; Steinbuch, M.

2008-01-01

This paper presents the synthesis, the implementation and the performance-based tuning of an Adaptive Cruise Control (ACC) Stop-&-Go (S&G) design. A Model Predictive Control (MPC) framework is adopted to design the controller. Performance of the controller is evaluated, distinguishing between

Active Learning by Querying Informative and Representative Examples.

Science.gov (United States)

Huang, Sheng-Jun; Jin, Rong; Zhou, Zhi-Hua

2014-10-01

Active learning reduces the labeling cost by iteratively selecting the most valuable data to query their labels. It has attracted a lot of interests given the abundance of unlabeled data and the high cost of labeling. Most active learning approaches select either informative or representative unlabeled instances to query their labels, which could significantly limit their performance. Although several active learning algorithms were proposed to combine the two query selection criteria, they are usually ad hoc in finding unlabeled instances that are both informative and representative. We address this limitation by developing a principled approach, termed QUIRE, based on the min-max view of active learning. The proposed approach provides a systematic way for measuring and combining the informativeness and representativeness of an unlabeled instance. Further, by incorporating the correlation among labels, we extend the QUIRE approach to multi-label learning by actively querying instance-label pairs. Extensive experimental results show that the proposed QUIRE approach outperforms several state-of-the-art active learning approaches in both single-label and multi-label learning.

Performance Analysis of Two Big Data Technologies on a Cloud Distributed Architecture. Results for Non-Aggregate Queries on Medium-Sized Data

Directory of Open Access Journals (Sweden)

Fotache Marin

2016-12-01

Full Text Available Big Data systems manage and process huge volumes of data constantly generated by various technologies in a myriad of formats. Big Data advocates (and preachers have claimed that, relative to classical, relational/SQL Data Base Management Systems, Big Data technologies such as NoSQL, Hadoop and in-memory data stores perform better. This paper compares data processing performance of two systems belonging to SQL (PostgreSQL/Postgres XL and Big Data (Hadoop/Hive camps on a distributed five-node cluster deployed in cloud. Unlike benchmarks in use (YCSB, TPC, a series of R modules were devised for generating random non-aggregate queries on different subschema (with increasing data size of TPC-H database. Overall performance of the two systems was compared. Subsequently a number of models were developed for relating performance on the system and also on various query parameters such as the number of attributes in SELECT and WHERE clause, number of joins, number of processing rows etc.

Multi-Dimensional Path Queries

DEFF Research Database (Denmark)

Bækgaard, Lars

1998-01-01

to create nested path structures. We present an SQL-like query language that is based on path expressions and we show how to use it to express multi-dimensional path queries that are suited for advanced data analysis in decision support environments like data warehousing environments......We present the path-relationship model that supports multi-dimensional data modeling and querying. A path-relationship database is composed of sets of paths and sets of relationships. A path is a sequence of related elements (atoms, paths, and sets of paths). A relationship is a binary path...

Learning via Query Synthesis

KAUST Repository

Alabdulmohsin, Ibrahim

2017-01-01

Active learning is a subfield of machine learning that has been successfully used in many applications. One of the main branches of active learning is query synthe- sis, where the learning agent constructs artificial queries from scratch in order

An Adaptive Genetic Algorithm with Dynamic Population Size for Optimizing Join Queries

OpenAIRE

Vellev, Stoyan

2008-01-01

The problem of finding the optimal join ordering executing a query to a relational database management system is a combinatorial optimization problem, which makes deterministic exhaustive solution search unacceptable for queries with a great number of joined relations. In this work an adaptive genetic algorithm with dynamic population size is proposed for optimizing large join queries. The performance of the algorithm is compared with that of several classical non-determinis...

Optimizing Temporal Queries: Efficient Handling of Duplicates

DEFF Research Database (Denmark)

Toman, David; Bowman, Ivan Thomas

2001-01-01

, these query languages are implemented by translating temporal queries into standard relational queries. However, the compiled queries are often quite cumbersome and expensive to execute even using state-of-the- art relational products. This paper presents an optimization technique that produces more efficient...... translated SQL queries by taking into account the properties of the encoding used for temporal attributes. For concreteness, this translation technique is presented in the context of SQL/TP; however, these techniques are also applicable to other temporal query languages....

Accelerating SPARQL Queries and Analytics on RDF Data

KAUST Repository

Al-Harbi, Razen

2016-11-09

The complexity of SPARQL queries and RDF applications poses great challenges on distributed RDF management systems. SPARQL workloads are dynamic and con- sist of queries with variable complexities. Hence, systems that use static partitioning su↵er from communication overhead for workloads that generate excessive communi- cation. Concurrently, RDF applications are becoming more sophisticated, mandating analytical operations that extend beyond SPARQL queries. Being primarily designed and optimized to execute SPARQL queries, which lack procedural capabilities, exist- ing systems are not suitable for rich RDF analytics. This dissertation tackles the problem of accelerating SPARQL queries and RDF analytics on distributed shared-nothing RDF systems. First, a distributed RDF en- gine, coined AdPart, is introduced. AdPart uses lightweight hash partitioning for sharding triples using their subject values; rendering its startup overhead very low. The locality-aware query optimizer of AdPart takes full advantage of the partition- ing to (i) support the fully parallel processing of join patterns on subjects and (ii) minimize data communication for general queries by applying hash distribution of intermediate results instead of broadcasting, wherever possible. By exploiting hash- based locality, AdPart achieves better or comparable performance to systems that employ sophisticated partitioning schemes. To cope with workloads dynamism, AdPart is extended to dynamically adapt to workload changes. AdPart monitors the data access patterns and dynamically redis- tributes and replicates the instances of the most frequent patterns among workers.Consequently, the communication cost for future queries is drastically reduced or even eliminated. Experiments with synthetic and real data verify that AdPart starts faster than all existing systems and gracefully adapts to the query load. Finally, to support and accelerate rich RDF analytical tasks, a vertex-centric RDF analytics framework is

Searching for rare diseases in PubMed: a blind comparison of Orphanet expert query and query based on terminological knowledge.

Science.gov (United States)

Griffon, N; Schuers, M; Dhombres, F; Merabti, T; Kerdelhué, G; Rollin, L; Darmoni, S J

2016-08-02

Despite international initiatives like Orphanet, it remains difficult to find up-to-date information about rare diseases. The aim of this study is to propose an exhaustive set of queries for PubMed based on terminological knowledge and to evaluate it versus the queries based on expertise provided by the most frequently used resource in Europe: Orphanet. Four rare disease terminologies (MeSH, OMIM, HPO and HRDO) were manually mapped to each other permitting the automatic creation of expended terminological queries for rare diseases. For 30 rare diseases, 30 citations retrieved by Orphanet expert query and/or query based on terminological knowledge were assessed for relevance by two independent reviewers unaware of the query's origin. An adjudication procedure was used to resolve any discrepancy. Precision, relative recall and F-measure were all computed. For each Orphanet rare disease (n = 8982), there was a corresponding terminological query, in contrast with only 2284 queries provided by Orphanet. Only 553 citations were evaluated due to queries with 0 or only a few hits. There were no significant differences between the Orpha query and terminological query in terms of precision, respectively 0.61 vs 0.52 (p = 0.13). Nevertheless, terminological queries retrieved more citations more often than Orpha queries (0.57 vs. 0.33; p = 0.01). Interestingly, Orpha queries seemed to retrieve older citations than terminological queries (p < 0.0001). The terminological queries proposed in this study are now currently available for all rare diseases. They may be a useful tool for both precision or recall oriented literature search.

Pro PHP and jQuery

CERN Document Server

Lengstorf, Jason

2010-01-01

This book is for intermediate programmers interested in building AJAX web applications using jQuery and PHP. Along with teaching some advanced PHP techniques, it will teach you how to take your dynamic applications to the next level by adding a JavaScript layer with jQuery. * Learn to utilize built-in PHP functions to build calendar tools.* Learn how jQuery can be used for AJAX, animation, client-side validation, and more.What you'll learn* Use PHP to build a calendar application that allows users to post, view, edit, and delete events.* Use jQuery to allow the calendar app to be viewed and ed

Query recommendation for children

NARCIS (Netherlands)

Duarte Torres, Sergio; Hiemstra, Djoerd; Weber, Ingmar; Serdyukov, Pavel

2012-01-01

One of the biggest problems that children experience while searching the web occurs during the query formulation process. Children have been found to struggle formulating queries based on keywords given their limited vocabulary and their difficulty to choose the right keywords. In this work we

DISPAQ: Distributed Profitable-Area Query from Big Taxi Trip Data.

Science.gov (United States)

Putri, Fadhilah Kurnia; Song, Giltae; Kwon, Joonho; Rao, Praveen

2017-09-25

One of the crucial problems for taxi drivers is to efficiently locate passengers in order to increase profits. The rapid advancement and ubiquitous penetration of Internet of Things (IoT) technology into transportation industries enables us to provide taxi drivers with locations that have more potential passengers (more profitable areas) by analyzing and querying taxi trip data. In this paper, we propose a query processing system, called Distributed Profitable-Area Query ( DISPAQ ) which efficiently identifies profitable areas by exploiting the Apache Software Foundation's Spark framework and a MongoDB database. DISPAQ first maintains a profitable-area query index (PQ-index) by extracting area summaries and route summaries from raw taxi trip data. It then identifies candidate profitable areas by searching the PQ-index during query processing. Then, it exploits a Z-Skyline algorithm, which is an extension of skyline processing with a Z-order space filling curve, to quickly refine the candidate profitable areas. To improve the performance of distributed query processing, we also propose local Z-Skyline optimization, which reduces the number of dominant tests by distributing killer profitable areas to each cluster node. Through extensive evaluation with real datasets, we demonstrate that our DISPAQ system provides a scalable and efficient solution for processing profitable-area queries from huge amounts of big taxi trip data.

Facilitating Cohort Discovery by Enhancing Ontology Exploration, Query Management and Query Sharing for Large Clinical Data Repositories

Science.gov (United States)

Tao, Shiqiang; Cui, Licong; Wu, Xi; Zhang, Guo-Qiang

2017-01-01

To help researchers better access clinical data, we developed a prototype query engine called DataSphere for exploring large-scale integrated clinical data repositories. DataSphere expedites data importing using a NoSQL data management system and dynamically renders its user interface for concept-based querying tasks. DataSphere provides an interactive query-building interface together with query translation and optimization strategies, which enable users to build and execute queries effectively and efficiently. We successfully loaded a dataset of one million patients for University of Kentucky (UK) Healthcare into DataSphere with more than 300 million clinical data records. We evaluated DataSphere by comparing it with an instance of i2b2 deployed at UK Healthcare, demonstrating that DataSphere provides enhanced user experience for both query building and execution. PMID:29854239

Facilitating Cohort Discovery by Enhancing Ontology Exploration, Query Management and Query Sharing for Large Clinical Data Repositories.

Science.gov (United States)

Tao, Shiqiang; Cui, Licong; Wu, Xi; Zhang, Guo-Qiang

2017-01-01

To help researchers better access clinical data, we developed a prototype query engine called DataSphere for exploring large-scale integrated clinical data repositories. DataSphere expedites data importing using a NoSQL data management system and dynamically renders its user interface for concept-based querying tasks. DataSphere provides an interactive query-building interface together with query translation and optimization strategies, which enable users to build and execute queries effectively and efficiently. We successfully loaded a dataset of one million patients for University of Kentucky (UK) Healthcare into DataSphere with more than 300 million clinical data records. We evaluated DataSphere by comparing it with an instance of i2b2 deployed at UK Healthcare, demonstrating that DataSphere provides enhanced user experience for both query building and execution.

Towards Verbalizing SPARQL Queries in Arabic

Directory of Open Access Journals (Sweden)

I. Al Agha

2016-04-01

Full Text Available With the wide spread of Open Linked Data and Semantic Web technologies, a larger amount of data has been published on the Web in the RDF and OWL formats. This data can be queried using SPARQL, the Semantic Web Query Language. SPARQL cannot be understood by ordinary users and is not directly accessible to humans, and thus they will not be able to check whether the retrieved answers truly correspond to the intended information need. Driven by this challenge, natural language generation from SPARQL data has recently attracted a considerable attention. However, most existing solutions to verbalize SPARQL in natural language focused on English and Latin-based languages. Little effort has been made on the Arabic language which has different characteristics and morphology. This work aims to particularly help Arab users to perceive SPARQL queries on the Semantic Web by translating SPARQL to Arabic. It proposes an approach that gets a SPARQL query as an input and generates a query expressed in Arabic as an output. The translation process combines both morpho-syntactic analysis and language dependencies to generate a legible and understandable Arabic query. The approach was preliminary assessed with a sample query set, and results indicated that 75% of the queries were correctly translated into Arabic.

A Framework for WWW Query Processing

Science.gov (United States)

Wu, Binghui Helen; Wharton, Stephen (Technical Monitor)

2000-01-01

Query processing is the most common operation in a DBMS. Sophisticated query processing has been mainly targeted at a single enterprise environment providing centralized control over data and metadata. Submitting queries by anonymous users on the web is different in such a way that load balancing or DBMS' accessing control becomes the key issue. This paper provides a solution by introducing a framework for WWW query processing. The success of this framework lies in the utilization of query optimization techniques and the ontological approach. This methodology has proved to be cost effective at the NASA Goddard Space Flight Center Distributed Active Archive Center (GDAAC).

Learning via Query Synthesis

KAUST Repository

Alabdulmohsin, Ibrahim Mansour

2017-05-07

Active learning is a subfield of machine learning that has been successfully used in many applications. One of the main branches of active learning is query synthe- sis, where the learning agent constructs artificial queries from scratch in order to reveal sensitive information about the underlying decision boundary. It has found applications in areas, such as adversarial reverse engineering, automated science, and computational chemistry. Nevertheless, the existing literature on membership query synthesis has, generally, focused on finite concept classes or toy problems, with a limited extension to real-world applications. In this thesis, I develop two spectral algorithms for learning halfspaces via query synthesis. The first algorithm is a maximum-determinant convex optimization method while the second algorithm is a Markovian method that relies on Khachiyan’s classical update formulas for solving linear programs. The general theme of these methods is to construct an ellipsoidal approximation of the version space and to synthesize queries, afterward, via spectral decomposition. Moreover, I also describe how these algorithms can be extended to other settings as well, such as pool-based active learning. Having demonstrated that halfspaces can be learned quite efficiently via query synthesis, the second part of this thesis proposes strategies for mitigating the risk of reverse engineering in adversarial environments. One approach that can be used to render query synthesis algorithms ineffective is to implement a randomized response. In this thesis, I propose a semidefinite program (SDP) for learning a distribution of classifiers, subject to the constraint that any individual classifier picked at random from this distributions provides reliable predictions with a high probability. This algorithm is, then, justified both theoretically and empirically. A second approach is to use a non-parametric classification method, such as similarity-based classification. In this

Object-Oriented Query Language For Events Detection From Images Sequences

Science.gov (United States)

Ganea, Ion Eugen

2015-09-01

In this paper is presented a method to represent the events extracted from images sequences and the query language used for events detection. Using an object oriented model the spatial and temporal relationships between salient objects and also between events are stored and queried. This works aims to unify the storing and querying phases for video events processing. The object oriented language syntax used for events processing allow the instantiation of the indexes classes in order to improve the accuracy of the query results. The experiments were performed on images sequences provided from sport domain and it shows the reliability and the robustness of the proposed language. To extend the language will be added a specific syntax for constructing the templates for abnormal events and for detection of the incidents as the final goal of the research.

jQuery Tools UI Library

CERN Document Server

Libby, Alex

2012-01-01

A practical tutorial with powerful yet simple projects that are quick to implement. This book is aimed at developers who have prior jQuery knowledge, but may not have any prior experience with jQuery Tools. It is possible that they may have started with the basics of jQuery Tools, but want to learn more about how it can be used, as well as get ideas for future projects.

Joint Top-K Spatial Keyword Query Processing

DEFF Research Database (Denmark)

Wu, Dingming; Yiu, Man Lung; Cong, Gao

2012-01-01

Web users and content are increasingly being geopositioned, and increased focus is being given to serving local content in response to web queries. This development calls for spatial keyword queries that take into account both the locations and textual descriptions of content. We study the effici......Web users and content are increasingly being geopositioned, and increased focus is being given to serving local content in response to web queries. This development calls for spatial keyword queries that take into account both the locations and textual descriptions of content. We study...... the efficient, joint processing of multiple top-k spatial keyword queries. Such joint processing is attractive during high query loads and also occurs when multiple queries are used to obfuscate a user's true query. We propose a novel algorithm and index structure for the joint processing of top-k spatial...... keyword queries. Empirical studies show that the proposed solution is efficient on real data sets. We also offer analytical studies on synthetic data sets to demonstrate the efficiency of the proposed solution. Index Terms IEEE Terms Electronic mail , Google , Indexes , Joints , Mobile communication...

Fast Inbound Top-K Query for Random Walk with Restart.

Science.gov (United States)

Zhang, Chao; Jiang, Shan; Chen, Yucheng; Sun, Yidan; Han, Jiawei

2015-09-01

Random walk with restart (RWR) is widely recognized as one of the most important node proximity measures for graphs, as it captures the holistic graph structure and is robust to noise in the graph. In this paper, we study a novel query based on the RWR measure, called the inbound top-k (Ink) query. Given a query node q and a number k , the Ink query aims at retrieving k nodes in the graph that have the largest weighted RWR scores to q . Ink queries can be highly useful for various applications such as traffic scheduling, disease treatment, and targeted advertising. Nevertheless, none of the existing RWR computation techniques can accurately and efficiently process the Ink query in large graphs. We propose two algorithms, namely Squeeze and Ripple, both of which can accurately answer the Ink query in a fast and incremental manner. To identify the top- k nodes, Squeeze iteratively performs matrix-vector multiplication and estimates the lower and upper bounds for all the nodes in the graph. Ripple employs a more aggressive strategy by only estimating the RWR scores for the nodes falling in the vicinity of q , the nodes outside the vicinity do not need to be evaluated because their RWR scores are propagated from the boundary of the vicinity and thus upper bounded. Ripple incrementally expands the vicinity until the top- k result set can be obtained. Our extensive experiments on real-life graph data sets show that Ink queries can retrieve interesting results, and the proposed algorithms are orders of magnitude faster than state-of-the-art method.

Improving biomedical information retrieval by linear combinations of different query expansion techniques.

Science.gov (United States)

Abdulla, Ahmed AbdoAziz Ahmed; Lin, Hongfei; Xu, Bo; Banbhrani, Santosh Kumar

2016-07-25

Biomedical literature retrieval is becoming increasingly complex, and there is a fundamental need for advanced information retrieval systems. Information Retrieval (IR) programs scour unstructured materials such as text documents in large reserves of data that are usually stored on computers. IR is related to the representation, storage, and organization of information items, as well as to access. In IR one of the main problems is to determine which documents are relevant and which are not to the user's needs. Under the current regime, users cannot precisely construct queries in an accurate way to retrieve particular pieces of data from large reserves of data. Basic information retrieval systems are producing low-quality search results. In our proposed system for this paper we present a new technique to refine Information Retrieval searches to better represent the user's information need in order to enhance the performance of information retrieval by using different query expansion techniques and apply a linear combinations between them, where the combinations was linearly between two expansion results at one time. Query expansions expand the search query, for example, by finding synonyms and reweighting original terms. They provide significantly more focused, particularized search results than do basic search queries. The retrieval performance is measured by some variants of MAP (Mean Average Precision) and according to our experimental results, the combination of best results of query expansion is enhanced the retrieved documents and outperforms our baseline by 21.06 %, even it outperforms a previous study by 7.12 %. We propose several query expansion techniques and their combinations (linearly) to make user queries more cognizable to search engines and to produce higher-quality search results.

The Ontology Lookup Service: more data and better tools for controlled vocabulary queries.

Science.gov (United States)

Côté, Richard G; Jones, Philip; Martens, Lennart; Apweiler, Rolf; Hermjakob, Henning

2008-07-01

The Ontology Lookup Service (OLS) (http://www.ebi.ac.uk/ols) provides interactive and programmatic interfaces to query, browse and navigate an ever increasing number of biomedical ontologies and controlled vocabularies. The volume of data available for querying has more than quadrupled since it went into production and OLS functionality has been integrated into several high-usage databases and data entry tools. Improvements have been made to both OLS query interfaces, based on user feedback and requirements, to improve usability and service interoperability and provide novel ways to perform queries.

Research Issues in Mobile Querying

DEFF Research Database (Denmark)

Breunig, M.; Jensen, Christian Søndergaard; Klein, M.

2004-01-01

This document reports on key aspects of the discussions conducted within the working group. In particular, the document aims to offer a structured and somewhat digested summary of the group's discussions. The document first offers concepts that enable characterization of "mobile queries" as well...... as the types of systems that enable such queries. It explores the notion of context in mobile queries. The document ends with a few observations, mainly regarding challenges....

On tractable query evaluation for SPARQL

OpenAIRE

Mengel, Stefan; Skritek, Sebastian

2017-01-01

Despite much work within the last decade on foundational properties of SPARQL - the standard query language for RDF data - rather little is known about the exact limits of tractability for this language. In particular, this is the case for SPARQL queries that contain the OPTIONAL-operator, even though it is one of the most intensively studied features of SPARQL. The aim of our work is to provide a more thorough picture of tractable classes of SPARQL queries. In general, SPARQL query evaluatio...

Man vs. Machine: Differences in SPARQL Queries

NARCIS (Netherlands)

Rietveld, L.; Hoekstra, R.

2014-01-01

Server-side SPARQL query logs have been a topic of study for some time now. The USEWOD collection of query logs is currently the primary source of information for researchers. A recurring problem is that these logs leave application queries and queries created by humans indistinguishable. In this

Improving accuracy for identifying related PubMed queries by an integrated approach.

Science.gov (United States)

Lu, Zhiyong; Wilbur, W John

2009-10-01

PubMed is the most widely used tool for searching biomedical literature online. As with many other online search tools, a user often types a series of multiple related queries before retrieving satisfactory results to fulfill a single information need. Meanwhile, it is also a common phenomenon to see a user type queries on unrelated topics in a single session. In order to study PubMed users' search strategies, it is necessary to be able to automatically separate unrelated queries and group together related queries. Here, we report a novel approach combining both lexical and contextual analyses for segmenting PubMed query sessions and identifying related queries and compare its performance with the previous approach based solely on concept mapping. We experimented with our integrated approach on sample data consisting of 1539 pairs of consecutive user queries in 351 user sessions. The prediction results of 1396 pairs agreed with the gold-standard annotations, achieving an overall accuracy of 90.7%. This demonstrates that our approach is significantly better than the previously published method. By applying this approach to a one day query log of PubMed, we found that a significant proportion of information needs involved more than one PubMed query, and that most of the consecutive queries for the same information need are lexically related. Finally, the proposed PubMed distance is shown to be an accurate and meaningful measure for determining the contextual similarity between biological terms. The integrated approach can play a critical role in handling real-world PubMed query log data as is demonstrated in our experiments.

Querying XML Data with SPARQL

Science.gov (United States)

Bikakis, Nikos; Gioldasis, Nektarios; Tsinaraki, Chrisa; Christodoulakis, Stavros

SPARQL is today the standard access language for Semantic Web data. In the recent years XML databases have also acquired industrial importance due to the widespread applicability of XML in the Web. In this paper we present a framework that bridges the heterogeneity gap and creates an interoperable environment where SPARQL queries are used to access XML databases. Our approach assumes that fairly generic mappings between ontology constructs and XML Schema constructs have been automatically derived or manually specified. The mappings are used to automatically translate SPARQL queries to semantically equivalent XQuery queries which are used to access the XML databases. We present the algorithms and the implementation of SPARQL2XQuery framework, which is used for answering SPARQL queries over XML databases.

Superfund Query

Data.gov (United States)

U.S. Environmental Protection Agency — The Superfund Query allows users to retrieve data from the Comprehensive Environmental Response, Compensation, and Liability Information System (CERCLIS) database.

Using Query Languages and Mobile Code to Reduce Service Invocation Costs

National Research Council Canada - National Science Library

Szymanski, R; Palmer, N; Chase, T

2006-01-01

.... As a concrete example, this paper describes work being performed by CERDEC C2D (Communications Electronics Research, Development, and Engineering Center - Command and Control Directorate) at Fort Monmouth, NJ to expose a military mission plan as a web service through the use of simple SQL-like (Structured Query Language) statements optimized for mission data query.

Optimizing queries in distributed systems

Directory of Open Access Journals (Sweden)

Ion LUNGU

2006-01-01

Full Text Available This research presents the main elements of query optimizations in distributed systems. First, data architecture according with system level architecture in a distributed environment is presented. Then the architecture of a distributed database management system (DDBMS is described on conceptual level followed by the presentation of the distributed query execution steps on these information systems. The research ends with presentation of some aspects of distributed database query optimization and strategies used for that.

Advanced Query Formulation in Deductive Databases.

Science.gov (United States)

Niemi, Timo; Jarvelin, Kalervo

1992-01-01

Discusses deductive databases and database management systems (DBMS) and introduces a framework for advanced query formulation for end users. Recursive processing is described, a sample extensional database is presented, query types are explained, and criteria for advanced query formulation from the end user's viewpoint are examined. (31…

Dynamic Planar Range Maxima Queries

DEFF Research Database (Denmark)

Brodal, Gerth Stølting; Tsakalidis, Konstantinos

2011-01-01

We consider the dynamic two-dimensional maxima query problem. Let P be a set of n points in the plane. A point is maximal if it is not dominated by any other point in P. We describe two data structures that support the reporting of the t maximal points that dominate a given query point, and allow...... for insertions and deletions of points in P. In the pointer machine model we present a linear space data structure with O(logn + t) worst case query time and O(logn) worst case update time. This is the first dynamic data structure for the planar maxima dominance query problem that achieves these bounds...... are integers in the range U = {0, …,2 w  − 1 }. We present a linear space data structure that supports 3-sided range maxima queries in O(logn/loglogn+t) worst case time and updates in O(logn/loglogn) worst case time. These are the first sublogarithmic worst case bounds for all operations in the RAM model....

Predicting Drug Recalls From Internet Search Engine Queries.

Science.gov (United States)

Yom-Tov, Elad

2017-01-01

Batches of pharmaceuticals are sometimes recalled from the market when a safety issue or a defect is detected in specific production runs of a drug. Such problems are usually detected when patients or healthcare providers report abnormalities to medical authorities. Here, we test the hypothesis that defective production lots can be detected earlier by monitoring queries to Internet search engines. We extracted queries from the USA to the Bing search engine, which mentioned one of the 5195 pharmaceutical drugs during 2015 and all recall notifications issued by the Food and Drug Administration (FDA) during that year. By using attributes that quantify the change in query volume at the state level, we attempted to predict if a recall of a specific drug will be ordered by FDA in a time horizon ranging from 1 to 40 days in future. Our results show that future drug recalls can indeed be identified with an AUC of 0.791 and a lift at 5% of approximately 6 when predicting a recall occurring one day ahead. This performance degrades as prediction is made for longer periods ahead. The most indicative attributes for prediction are sudden spikes in query volume about a specific medicine in each state. Recalls of prescription drugs and those estimated to be of medium-risk are more likely to be identified using search query data. These findings suggest that aggregated Internet search engine data can be used to facilitate in early warning of faulty batches of medicines.

Evaluation of Content-Matched Range Monitoring Queries over Moving Objects in Mobile Computing Environments.

Science.gov (United States)

Jung, HaRim; Song, MoonBae; Youn, Hee Yong; Kim, Ung Mo

2015-09-18

A content-matched (CM) rangemonitoring query overmoving objects continually retrieves the moving objects (i) whose non-spatial attribute values are matched to given non-spatial query values; and (ii) that are currently located within a given spatial query range. In this paper, we propose a new query indexing structure, called the group-aware query region tree (GQR-tree) for efficient evaluation of CMrange monitoring queries. The primary role of the GQR-tree is to help the server leverage the computational capabilities of moving objects in order to improve the system performance in terms of the wireless communication cost and server workload. Through a series of comprehensive simulations, we verify the superiority of the GQR-tree method over the existing methods.

Evaluation of Content-Matched Range Monitoring Queries over Moving Objects in Mobile Computing Environments

Directory of Open Access Journals (Sweden)

HaRim Jung

2015-09-01

Full Text Available A content-matched (CM rangemonitoring query overmoving objects continually retrieves the moving objects (i whose non-spatial attribute values are matched to given non-spatial query values; and (ii that are currently located within a given spatial query range. In this paper, we propose a new query indexing structure, called the group-aware query region tree (GQR-tree for efficient evaluation of CMrange monitoring queries. The primary role of the GQR-tree is to help the server leverage the computational capabilities of moving objects in order to improve the system performance in terms of the wireless communication cost and server workload. Through a series of comprehensive simulations, we verify the superiority of the GQR-tree method over the existing methods.

A P2P Query Algorithm for Opportunistic Networks Utilizing betweenness Centrality Forwarding

Directory of Open Access Journals (Sweden)

Jianwei Niu

2013-01-01

Full Text Available With the proliferation of high-end mobile devices that feature wireless interfaces, many promising applications are enabled in opportunistic networks. In contrary to traditional networks, opportunistic networks utilize the mobility of nodes to relay messages in a store-carry-forward paradigm. Thus, the relay process in opportunistic networks faces several practical challenges in terms of delay and delivery rate. In this paper, we propose a novel P2P Query algorithm, namely Betweenness Centrality Forwarding (PQBCF, for opportunistic networking. PQBCF adopts a forwarding metric called Betweenness Centrality (BC, which is borrowed from social network, to quantify the active degree of nodes in the networks. In PQBCF, nodes with a higher BC are preferable to serve as relays, leading to higher query success rate and lower query delay. A comparison with the state-of-the-art algorithms reveals that PQBCF can provide better performance on both the query success Ratio and query delay, and approaches the performance of Epidemic Routing (ER with much less resource consumption.

Nearest Neighbor Queries in Road Networks

DEFF Research Database (Denmark)

Jensen, Christian Søndergaard; Kolar, Jan; Pedersen, Torben Bach

2003-01-01

in road networks. Such queries may be of use in many services. Specifically, we present an easily implementable data model that serves well as a foundation for such queries. We also present the design of a prototype system that implements the queries based on the data model. The algorithm used...

Fingerprinting Keywords in Search Queries over Tor

Directory of Open Access Journals (Sweden)

Oh Se Eun

2017-10-01

Full Text Available Search engine queries contain a great deal of private and potentially compromising information about users. One technique to prevent search engines from identifying the source of a query, and Internet service providers (ISPs from identifying the contents of queries is to query the search engine over an anonymous network such as Tor.

Adaptive Self-Tuning Networks

Science.gov (United States)

Knox, H. A.; Draelos, T.; Young, C. J.; Lawry, B.; Chael, E. P.; Faust, A.; Peterson, M. G.

2015-12-01

The quality of automatic detections from seismic sensor networks depends on a large number of data processing parameters that interact in complex ways. The largely manual process of identifying effective parameters is painstaking and does not guarantee that the resulting controls are the optimal configuration settings. Yet, achieving superior automatic detection of seismic events is closely related to these parameters. We present an automated sensor tuning (AST) system that learns near-optimal parameter settings for each event type using neuro-dynamic programming (reinforcement learning) trained with historic data. AST learns to test the raw signal against all event-settings and automatically self-tunes to an emerging event in real-time. The overall goal is to reduce the number of missed legitimate event detections and the number of false event detections. Reducing false alarms early in the seismic pipeline processing will have a significant impact on this goal. Applicable both for existing sensor performance boosting and new sensor deployment, this system provides an important new method to automatically tune complex remote sensing systems. Systems tuned in this way will achieve better performance than is currently possible by manual tuning, and with much less time and effort devoted to the tuning process. With ground truth on detections in seismic waveforms from a network of stations, we show that AST increases the probability of detection while decreasing false alarms.

QUERY SUPPORT FOR GMZ

Directory of Open Access Journals (Sweden)

A. Khandelwal

2017-07-01

Full Text Available Generic text-based compression models are simple and fast but there are two issues that needs to be addressed. They cannot leverage the structure that exists in data to achieve better compression and there is an unnecessary decompression step before the user can actually use the data. To address these issues, we came up with GMZ, a lossless compression model aimed at achieving high compression ratios. The decision to design GMZ (Khandelwal and Rajan, 2017 exclusively for GML's Simple Features Profile (SFP seems fair because of the high use of SFP in WFS and that it facilitates high optimisation of the compression model. This is an extension of our work on GMZ. In a typical server-client model such as Web Feature Service, the server is the primary creator and provider of GML, and therefore, requires compression and query capabilities. On the other hand, the client is the primary consumer of GML, and therefore, requires decompression and visualisation capabilities. In the first part of our work, we demonstrated compression using a python script that can be plugged in a server architecture, and decompression and visualisation in a web browser using a Firefox addon. The focus of this work is to develop the already existing tools to provide query capability to server. Our model provides the ability to decompress individual features in isolation, which is an essential requirement for realising query in compressed state. We con - struct an R-Tree index for spatial data and a custom index for non-spatial data and store these in a separate index file to prevent alter - ing the compression model. This facilitates independent use of compressed GMZ file where index can be constructed when required. The focus of this work is the bounding-box or range query commonly used in webGIS with provision for other spatial and non-spatial queries. The decrement in compression ratios due to the new index file is in the range of 1–3 percent which is trivial considering

Ranking Queries on Uncertain Data

CERN Document Server

Hua, Ming

2011-01-01

Uncertain data is inherent in many important applications, such as environmental surveillance, market analysis, and quantitative economics research. Due to the importance of those applications and rapidly increasing amounts of uncertain data collected and accumulated, analyzing large collections of uncertain data has become an important task. Ranking queries (also known as top-k queries) are often natural and useful in analyzing uncertain data. Ranking Queries on Uncertain Data discusses the motivations/applications, challenging problems, the fundamental principles, and the evaluation algorith

Recommendation Sets and Choice Queries

DEFF Research Database (Denmark)

Viappiani, Paolo Renato; Boutilier, Craig

2011-01-01

Utility elicitation is an important component of many applications, such as decision support systems and recommender systems. Such systems query users about their preferences and offer recommendations based on the system's belief about the user's utility function. We analyze the connection between...... the problem of generating optimal recommendation sets and the problem of generating optimal choice queries, considering both Bayesian and regret-based elicitation. Our results show that, somewhat surprisingly, under very general circumstances, the optimal recommendation set coincides with the optimal query....

Predecessor queries in dynamic integer sets

DEFF Research Database (Denmark)

Brodal, Gerth Stølting

1997-01-01

We consider the problem of maintaining a set of n integers in the range 0.2w–1 under the operations of insertion, deletion, predecessor queries, minimum queries and maximum queries on a unit cost RAM with word size w bits. Let f (n) be an arbitrary nondecreasing smooth function satisfying n...

New Path Based Index Structure for Processing CAS Queries over XML Database

Directory of Open Access Journals (Sweden)

Krishna Asawa

2017-01-01

Full Text Available Querying nested data has become one of the most challenging issues for retrieving desired information from the Web. Today diverse applications generate a tremendous amount of data in different formats. These data and information exchanged on the Web are commonly expressed as nested representation such as XML, JSON, etc. Unlike the traditional database system, they don't have a rigid schema. In general, the nested data is managed by storing data and its structures separately which significantly reduces the performance of data retrieving. Ensuring efficiency of processing queries which locates the exact positions of the elements has become a big challenging issue. There are different indexing structures which have been proposed in the literature to improve the performance of the query processing on the nested structure. Most of the past researches on nested structure concentrate on the structure alone. This paper proposes new index structure which combines siblings of the terminal nodes as one path which efficiently processes twig queries with less number of lookups and joins. The proposed approach is compared with some of the existing approaches. The results also show that they are processed with better performance compared to the existing ones.

Flexible Query Answering Systems 2006

DEFF Research Database (Denmark)

-computer interaction. The overall theme of the FQAS conferences is innovative query systems aimed at providing easy, flexible, and intuitive access to information. Such systems are intended to facilitate retrieval from information repositories such as databases, libraries, and the World-Wide Web. These repositories......This volume constitutes the proceedings of the Seventh International Conference on Flexible Query Answering Systems, FQAS 2006, held in Milan, Italy, on June 7--10, 2006. FQAS is the premier conference for researchers and practitioners concerned with the vital task of providing easy, flexible...... are typically equipped with standard query systems which are often inadequate, and the focus of FQAS is the development of query systems that are more expressive, informative, cooperative, and productive. These proceedings contain contributions from invited speakers and 53 original papers out of about 100...

Spatio-temporal databases complex motion pattern queries

CERN Document Server

Vieira, Marcos R

2013-01-01

This brief presents several new query processing techniques, called complex motion pattern queries, specifically designed for very large spatio-temporal databases of moving objects. The brief begins with the definition of flexible pattern queries, which are powerful because of the integration of variables and motion patterns. This is followed by a summary of the expressive power of patterns and flexibility of pattern queries. The brief then present the Spatio-Temporal Pattern System (STPS) and density-based pattern queries. STPS databases contain millions of records with information about mobi

Tag cloud generation for results of multiple keywords queries

DEFF Research Database (Denmark)

Leginus, Martin; Dolog, Peter; Lage, Ricardo Gomes

2013-01-01

In this paper we study tag cloud generation for retrieved results of multiple keyword queries. It is motivated by many real world scenarios such as personalization tasks, surveillance systems and information retrieval tasks defined with multiple keywords. We adjust the state-of-the-art tag cloud...... generation techniques for multiple keywords query results. Consequently, we conduct the extensive evaluation on top of three distinct collaborative tagging systems. The graph-based methods perform significantly better for the Movielens and Bibsonomy datasets. Tag cloud generation based on maximal coverage...

Design and analysis of stochastic DSS query optimizers in a distributed database system

Directory of Open Access Journals (Sweden)

Manik Sharma

2016-07-01

Full Text Available Query optimization is a stimulating task of any database system. A number of heuristics have been applied in recent times, which proposed new algorithms for substantially improving the performance of a query. The hunt for a better solution still continues. The imperishable developments in the field of Decision Support System (DSS databases are presenting data at an exceptional rate. The massive volume of DSS data is consequential only when it is able to access and analyze by distinctive researchers. Here, an innovative stochastic framework of DSS query optimizer is proposed to further optimize the design of existing query optimization genetic approaches. The results of Entropy Based Restricted Stochastic Query Optimizer (ERSQO are compared with the results of Exhaustive Enumeration Query Optimizer (EAQO, Simple Genetic Query Optimizer (SGQO, Novel Genetic Query Optimizer (NGQO and Restricted Stochastic Query Optimizer (RSQO. In terms of Total Costs, EAQO outperforms SGQO, NGQO, RSQO and ERSQO. However, stochastic approaches dominate in terms of runtime. The Total Costs produced by ERSQO is better than SGQO, NGQO and RGQO by 12%, 8% and 5% respectively. Moreover, the effect of replicating data on the Total Costs of DSS query is also examined. In addition, the statistical analysis revealed a 2-tailed significant correlation between the number of join operations and the Total Costs of distributed DSS query. Finally, in regard to the consistency of stochastic query optimizers, the results of SGQO, NGQO, RSQO and ERSQO are 96.2%, 97.2%, 97.45 and 97.8% consistent respectively.

DISPAQ: Distributed Profitable-Area Query from Big Taxi Trip Data †

Science.gov (United States)

Putri, Fadhilah Kurnia; Song, Giltae; Rao, Praveen

2017-01-01

One of the crucial problems for taxi drivers is to efficiently locate passengers in order to increase profits. The rapid advancement and ubiquitous penetration of Internet of Things (IoT) technology into transportation industries enables us to provide taxi drivers with locations that have more potential passengers (more profitable areas) by analyzing and querying taxi trip data. In this paper, we propose a query processing system, called Distributed Profitable-Area Query (DISPAQ) which efficiently identifies profitable areas by exploiting the Apache Software Foundation’s Spark framework and a MongoDB database. DISPAQ first maintains a profitable-area query index (PQ-index) by extracting area summaries and route summaries from raw taxi trip data. It then identifies candidate profitable areas by searching the PQ-index during query processing. Then, it exploits a Z-Skyline algorithm, which is an extension of skyline processing with a Z-order space filling curve, to quickly refine the candidate profitable areas. To improve the performance of distributed query processing, we also propose local Z-Skyline optimization, which reduces the number of dominant tests by distributing killer profitable areas to each cluster node. Through extensive evaluation with real datasets, we demonstrate that our DISPAQ system provides a scalable and efficient solution for processing profitable-area queries from huge amounts of big taxi trip data. PMID:28946679

Multi-Dimensional Top-k Dominating Queries

DEFF Research Database (Denmark)

Yiu, Man Lung; Mamoulis, Nikos

2009-01-01

The top-k dominating query returns k data objects which dominate the highest number of objects in a dataset. This query is an important tool for decision support since it provides data analysts an intuitive way for finding significant objects. In addition, it combines the advantages of top......-k and skyline queries without sharing their disadvantages: (i) the output size can be controlled, (ii) no ranking functions need to be specified by users, and (iii) the result is independent of the scales at different dimensions. Despite their importance, top-k dominating queries have not received adequate...

Query optimization over crowdsourced data

KAUST Repository

Park, Hyunjung; Widom, Jennifer

2013-01-01

Deco is a comprehensive system for answering declarative queries posed over stored relational data together with data obtained on-demand from the crowd. In this paper we describe Deco's cost-based query optimizer, building on Deco's data model

Query Optimizations over Decentralized RDF Graphs

KAUST Repository

Abdelaziz, Ibrahim

2017-05-18

Applications in life sciences, decentralized social networks, Internet of Things, and statistical linked dataspaces integrate data from multiple decentralized RDF graphs via SPARQL queries. Several approaches have been proposed to optimize query processing over a small number of heterogeneous data sources by utilizing schema information. In the case of schema similarity and interlinks among sources, these approaches cause unnecessary data retrieval and communication, leading to poor scalability and response time. This paper addresses these limitations and presents Lusail, a system for scalable and efficient SPARQL query processing over decentralized graphs. Lusail achieves scalability and low query response time through various optimizations at compile and run times. At compile time, we use a novel locality-aware query decomposition technique that maximizes the number of query triple patterns sent together to a source based on the actual location of the instances satisfying these triple patterns. At run time, we use selectivity-awareness and parallel query execution to reduce network latency and to increase parallelism by delaying the execution of subqueries expected to return large results. We evaluate Lusail using real and synthetic benchmarks, with data sizes up to billions of triples on an in-house cluster and a public cloud. We show that Lusail outperforms state-of-the-art systems by orders of magnitude in terms of scalability and response time.

jQuery UI 1.10 the user interface library for jQuery

CERN Document Server

Libby, Alex

2013-01-01

This book consists of an easy-to-follow, example-based approach that leads you step-by-step through the implementation and customization of each library component.This book is for frontend designers and developers who need to learn how to use jQuery UI quickly. To get the most out of this book, you should have a good working knowledge of HTML, CSS, and JavaScript, and should ideally be comfortable using jQuery.

Optimal Planar Orthogonal Skyline Counting Queries

DEFF Research Database (Denmark)

Brodal, Gerth Stølting; Larsen, Kasper Green

2014-01-01

counting queries, i.e. given a query rectangle R to report the size of the skyline of P\\cap R. We present a data structure for storing n points with integer coordinates having query time O(lg n/lglg n) and space usage O(n). The model of computation is a unit cost RAM with logarithmic word size. We prove...

Accelerating SPARQL queries by exploiting hash-based locality and adaptive partitioning

KAUST Repository

Al-Harbi, Razen

2016-02-08

State-of-the-art distributed RDF systems partition data across multiple computer nodes (workers). Some systems perform cheap hash partitioning, which may result in expensive query evaluation. Others try to minimize inter-node communication, which requires an expensive data preprocessing phase, leading to a high startup cost. Apriori knowledge of the query workload has also been used to create partitions, which, however, are static and do not adapt to workload changes. In this paper, we propose AdPart, a distributed RDF system, which addresses the shortcomings of previous work. First, AdPart applies lightweight partitioning on the initial data, which distributes triples by hashing on their subjects; this renders its startup overhead low. At the same time, the locality-aware query optimizer of AdPart takes full advantage of the partitioning to (1) support the fully parallel processing of join patterns on subjects and (2) minimize data communication for general queries by applying hash distribution of intermediate results instead of broadcasting, wherever possible. Second, AdPart monitors the data access patterns and dynamically redistributes and replicates the instances of the most frequent ones among workers. As a result, the communication cost for future queries is drastically reduced or even eliminated. To control replication, AdPart implements an eviction policy for the redistributed patterns. Our experiments with synthetic and real data verify that AdPart: (1) starts faster than all existing systems; (2) processes thousands of queries before other systems become online; and (3) gracefully adapts to the query load, being able to evaluate queries on billion-scale RDF data in subseconds.

PAQ: Persistent Adaptive Query Middleware for Dynamic Environments

Science.gov (United States)

Rajamani, Vasanth; Julien, Christine; Payton, Jamie; Roman, Gruia-Catalin

Pervasive computing applications often entail continuous monitoring tasks, issuing persistent queries that return continuously updated views of the operational environment. We present PAQ, a middleware that supports applications' needs by approximating a persistent query as a sequence of one-time queries. PAQ introduces an integration strategy abstraction that allows composition of one-time query responses into streams representing sophisticated spatio-temporal phenomena of interest. A distinguishing feature of our middleware is the realization that the suitability of a persistent query's result is a function of the application's tolerance for accuracy weighed against the associated overhead costs. In PAQ, programmers can specify an inquiry strategy that dictates how information is gathered. Since network dynamics impact the suitability of a particular inquiry strategy, PAQ associates an introspection strategy with a persistent query, that evaluates the quality of the query's results. The result of introspection can trigger application-defined adaptation strategies that alter the nature of the query. PAQ's simple API makes developing adaptive querying systems easily realizable. We present the key abstractions, describe their implementations, and demonstrate the middleware's usefulness through application examples and evaluation.

Correlation between National Influenza Surveillance Data and Search Queries from Mobile Devices and Desktops in South Korea.

Science.gov (United States)

Shin, Soo-Yong; Kim, Taerim; Seo, Dong-Woo; Sohn, Chang Hwan; Kim, Sung-Hoon; Ryoo, Seung Mok; Lee, Yoon-Seon; Lee, Jae Ho; Kim, Won Young; Lim, Kyoung Soo

2016-01-01

Digital surveillance using internet search queries can improve both the sensitivity and timeliness of the detection of a health event, such as an influenza outbreak. While it has recently been estimated that the mobile search volume surpasses the desktop search volume and mobile search patterns differ from desktop search patterns, the previous digital surveillance systems did not distinguish mobile and desktop search queries. The purpose of this study was to compare the performance of mobile and desktop search queries in terms of digital influenza surveillance. The study period was from September 6, 2010 through August 30, 2014, which consisted of four epidemiological years. Influenza-like illness (ILI) and virologic surveillance data from the Korea Centers for Disease Control and Prevention were used. A total of 210 combined queries from our previous survey work were used for this study. Mobile and desktop weekly search data were extracted from Naver, which is the largest search engine in Korea. Spearman's correlation analysis was used to examine the correlation of the mobile and desktop data with ILI and virologic data in Korea. We also performed lag correlation analysis. We observed that the influenza surveillance performance of mobile search queries matched or exceeded that of desktop search queries over time. The mean correlation coefficients of mobile search queries and the number of queries with an r-value of ≥ 0.7 equaled or became greater than those of desktop searches over the four epidemiological years. A lag correlation analysis of up to two weeks showed similar trends. Our study shows that mobile search queries for influenza surveillance have equaled or even become greater than desktop search queries over time. In the future development of influenza surveillance using search queries, the recognition of changing trend of mobile search data could be necessary.

Comparative Study of the Tuning Performances of the Nominal and Long L* CLIC Final Focus System at √s = 380 GeV

CERN Document Server

Plassard, F; Marin, E; Tomás, R

2017-01-01

Mitigation of static imperfections for emittance preservation is one of the most important and challenging tasks faced by the Compact Linear Collider (CLIC) beam delivery system. A simulation campaign has been performed to recover the nominal luminosity by means of different alignment procedures. The state of the art of the tuning studies is drawn up. Comparative studies of the tuning performances and a tuning-based final focus system design optimization for two L options are presented. The effectiveness of the tuning techniques applied to these different lattices will be decisive for the final layout of the CLIC final focus system at √s = 380 GeV.

EquiX-A Search and Query Language for XML.

Science.gov (United States)

Cohen, Sara; Kanza, Yaron; Kogan, Yakov; Sagiv, Yehoshua; Nutt, Werner; Serebrenik, Alexander

2002-01-01

Describes EquiX, a search language for XML that combines querying with searching to query the data and the meta-data content of Web pages. Topics include search engines; a data model for XML documents; search query syntax; search query semantics; an algorithm for evaluating a query on a document; and indexing EquiX queries. (LRW)

QUERY RESPONSE TIME COMPARISON NOSQLDB MONGODB WITH SQLDB ORACLE

Directory of Open Access Journals (Sweden)

Humasak T. A. Simanjuntak

2015-01-01

Full Text Available Penyimpanan data saat ini terdapat dua jenis yakni relational database dan non-relational database. Kedua jenis DBMS (Database Managemnet System tersebut berbeda dalam berbagai aspek seperti per-formansi eksekusi query, scalability, reliability maupun struktur penyimpanan data. Kajian ini memiliki tujuan untuk mengetahui perbandingan performansi DBMS antara Oracle sebagai jenis relational data-base dan MongoDB sebagai jenis non-relational database dalam mengolah data terstruktur. Eksperimen dilakukan untuk mengetahui perbandingan performansi kedua DBMS tersebut untuk operasi insert, select, update dan delete dengan menggunakan query sederhana maupun kompleks pada database Northwind. Untuk mencapai tujuan eksperimen, 18 query yang terdiri dari 2 insert query, 10 select query, 2 update query dan 2 delete query dieksekusi. Query dieksekusi melalui sebuah aplikasi .Net yang dibangun sebagai perantara antara user dengan basis data. Eksperimen dilakukan pada tabel dengan atau tanpa relasi pada Oracle dan embedded atau bukan embedded dokumen pada MongoDB. Response time untuk setiap eksekusi query dibandingkan dengan menggunakan metode statistik. Eksperimen menunjukkan response time query untuk proses select, insert, dan update pada MongoDB lebih cepatdaripada Oracle. MongoDB lebih cepat 64.8 % untuk select query;MongoDB lebihcepat 72.8 % untuk insert query dan MongoDB lebih cepat 33.9 % untuk update query. Pada delete query, Oracle lebih cepat 96.8 % daripada MongoDB untuk table yang berelasi, tetapi MongoDB lebih cepat 83.8 % daripada Oracle untuk table yang tidak memiliki relasi.Untuk query kompleks dengan Map Reduce pada MongoDB lebih lambat 97.6% daripada kompleks query dengan aggregate function pada Oracle.

Learning jQuery

CERN Document Server

Chaffer, Jonathan

2013-01-01

Step through each of the core concepts of the jQuery library, building an overall picture of its capabilities. Once you have thoroughly covered the basics, the book returns to each concept to cover more advanced examples and techniques.This book is for web designers who want to create interactive elements for their designs, and for developers who want to create the best user interface for their web applications. Basic JavaScript programming and knowledge of HTML and CSS is required. No knowledge of jQuery is assumed, nor is experience with any other JavaScript libraries.

Knowledge Query Language (KQL)

Science.gov (United States)

2016-02-12

described as a sparse, distributed multidimensional sorted map. Unlike a relational database , BigTable has no multicolumn primary keys or constraints. The...in query languages such as SQL. Figure 3. Address expression-based querying. Each circled step in Figure 3 is described below. Datastore/ Database ...implementation we describe in later sections stores the instance of registry ontology in JSON files. 7 Throughout the rest of this report, we use the

Graphical modeling and query language for hospitals.

Science.gov (United States)

Barzdins, Janis; Barzdins, Juris; Rencis, Edgars; Sostaks, Agris

2013-01-01

So far there has been little evidence that implementation of the health information technologies (HIT) is leading to health care cost savings. One of the reasons for this lack of impact by the HIT likely lies in the complexity of the business process ownership in the hospitals. The goal of our research is to develop a business model-based method for hospital use which would allow doctors to retrieve directly the ad-hoc information from various hospital databases. We have developed a special domain-specific process modelling language called the MedMod. Formally, we define the MedMod language as a profile on UML Class diagrams, but we also demonstrate it on examples, where we explain the semantics of all its elements informally. Moreover, we have developed the Process Query Language (PQL) that is based on MedMod process definition language. The purpose of PQL is to allow a doctor querying (filtering) runtime data of hospital's processes described using MedMod. The MedMod language tries to overcome deficiencies in existing process modeling languages, allowing to specify the loosely-defined sequence of the steps to be performed in the clinical process. The main advantages of PQL are in two main areas - usability and efficiency. They are: 1) the view on data through "glasses" of familiar process, 2) the simple and easy-to-perceive means of setting filtering conditions require no more expertise than using spreadsheet applications, 3) the dynamic response to each step in construction of the complete query that shortens the learning curve greatly and reduces the error rate, and 4) the selected means of filtering and data retrieving allows to execute queries in O(n) time regarding the size of the dataset. We are about to continue developing this project with three further steps. First, we are planning to develop user-friendly graphical editors for the MedMod process modeling and query languages. The second step is to do evaluation of usability the proposed language and tool

Enhancing Recall in Semantic Querying

DEFF Research Database (Denmark)

Rouces, Jacobo

2013-01-01

lexically and structurally different, which we will introduce in the next section. As RDF graphs from different sources are expected to be linked, the modeling heterogeneities will make the federated graph become sparser and inconsistent. This is detrimental to the recall of SPARQL queries, as the query...

Improve performance of scanning probe microscopy by balancing tuning fork prongs

International Nuclear Information System (INIS)

Ng, Boon Ping; Zhang Ying; Wei Kok, Shaw; Chai Soh, Yeng

2009-01-01

This paper presents an approach for improving the Q-factor of tuning fork probe used in scanning probe microscopes. The improvement is achieved by balancing the fork prongs with extra mass attachment. An analytical model is proposed to characterize the Q-factor of a tuning fork probe with respect to the attachment of extra mass on the tuning fork prongs, and based on the model, the Q-factors of the unbalanced and balanced tuning fork probes are derived and compared. Experimental results showed that the model fits well the experimental data and the approach can improve the Q-factor by more than a factor of three. The effectiveness of the approach is further demonstrated by applying the balanced probe on an atomic force microscope to obtain improved topographic images.

Widespread auditory deficits in tune deafness.

Science.gov (United States)

Jones, Jennifer L; Zalewski, Christopher; Brewer, Carmen; Lucker, Jay; Drayna, Dennis

2009-02-01

The goal of this study was to investigate auditory function in individuals with deficits in musical pitch perception. We hypothesized that such individuals have deficits in nonspeech areas of auditory processing. We screened 865 randomly selected individuals to identify those who scored poorly on the Distorted Tunes test (DTT), a measure of musical pitch recognition ability. Those who scored poorly were given a comprehensive audiologic examination, and those with hearing loss or other confounding audiologic factors were excluded from further testing. Thirty-five individuals with tune deafness constituted the experimental group. Thirty-four individuals with normal hearing and normal DTT scores, matched for age, gender, handedness, and education, and without overt or reported psychiatric disorders made up the normal control group. Individual and group performance for pure-tone frequency discrimination at 1000 Hz was determined by measuring the difference limen for frequency (DLF). Auditory processing abilities were assessed using tests of pitch pattern recognition, duration pattern recognition, and auditory gap detection. In addition, we evaluated both attention and short- and long-term memory as variables that might influence performance on our experimental measures. Differences between groups were evaluated statistically using Wilcoxon nonparametric tests and t-tests as appropriate. The DLF at 1000 Hz in the group with tune deafness was significantly larger than that of the normal control group. However, approximately one-third of participants with tune deafness had DLFs within the range of performance observed in the control group. Many individuals with tune deafness also displayed a high degree of variability in their intertrial frequency discrimination performance that could not be explained by deficits in memory or attention. Pitch and duration pattern discrimination and auditory gap-detection ability were significantly poorer in the group with tune deafness

SCRY: Enabling quantitative reasoning in SPARQL queries

NARCIS (Netherlands)

Meroño-Peñuela, A.; Stringer, Bas; Loizou, Antonis; Abeln, Sanne; Heringa, Jaap

2015-01-01

The inability to include quantitative reasoning in SPARQL queries slows down the application of Semantic Web technology in the life sciences. SCRY, our SPARQL compatible service layer, improves this by executing services at query time and making their outputs query-accessible, generating RDF data on

Answering SPARQL queries modulo RDF Schema with paths

OpenAIRE

Alkhateeb, Faisal; Euzenat, Jérôme

2013-01-01

alkhateeb2013a; SPARQL is the standard query language for RDF graphs. In its strict instantiation, it only offers querying according to the RDF semantics and would thus ignore the semantics of data expressed with respect to (RDF) schemas or (OWL) ontologies. Several extensions to SPARQL have been proposed to query RDF data modulo RDFS, i.e., interpreting the query with RDFS semantics and/or considering external ontologies. We introduce a general framework which allows for expressing query ans...

Automatic Query Generation and Query Relevance Measurement for Unsupervised Language Model Adaptation of Speech Recognition

Directory of Open Access Journals (Sweden)

Suzuki Motoyuki

2009-01-01

Full Text Available Abstract We are developing a method of Web-based unsupervised language model adaptation for recognition of spoken documents. The proposed method chooses keywords from the preliminary recognition result and retrieves Web documents using the chosen keywords. A problem is that the selected keywords tend to contain misrecognized words. The proposed method introduces two new ideas for avoiding the effects of keywords derived from misrecognized words. The first idea is to compose multiple queries from selected keyword candidates so that the misrecognized words and correct words do not fall into one query. The second idea is that the number of Web documents downloaded for each query is determined according to the "query relevance." Combining these two ideas, we can alleviate bad effect of misrecognized keywords by decreasing the number of downloaded Web documents from queries that contain misrecognized keywords. Finally, we examine a method of determining the number of iterative adaptations based on the recognition likelihood. Experiments have shown that the proposed stopping criterion can determine almost the optimum number of iterations. In the final experiment, the word accuracy without adaptation (55.29% was improved to 60.38%, which was 1.13 point better than the result of the conventional unsupervised adaptation method (59.25%.

Automatic Query Generation and Query Relevance Measurement for Unsupervised Language Model Adaptation of Speech Recognition

Directory of Open Access Journals (Sweden)

Akinori Ito

2009-01-01

Full Text Available We are developing a method of Web-based unsupervised language model adaptation for recognition of spoken documents. The proposed method chooses keywords from the preliminary recognition result and retrieves Web documents using the chosen keywords. A problem is that the selected keywords tend to contain misrecognized words. The proposed method introduces two new ideas for avoiding the effects of keywords derived from misrecognized words. The first idea is to compose multiple queries from selected keyword candidates so that the misrecognized words and correct words do not fall into one query. The second idea is that the number of Web documents downloaded for each query is determined according to the “query relevance.” Combining these two ideas, we can alleviate bad effect of misrecognized keywords by decreasing the number of downloaded Web documents from queries that contain misrecognized keywords. Finally, we examine a method of determining the number of iterative adaptations based on the recognition likelihood. Experiments have shown that the proposed stopping criterion can determine almost the optimum number of iterations. In the final experiment, the word accuracy without adaptation (55.29% was improved to 60.38%, which was 1.13 point better than the result of the conventional unsupervised adaptation method (59.25%.

Oracle SQL Tuning pocket Reference

CERN Document Server

Gurry, Mark

2002-01-01

One of the most important challenges faced by Oracle database administrators and Oracle developers is the need to tune SQL statements so that they execute efficiently. Poorly tuned SQL statements are one of the leading causes of substandard database performance and poor response time. SQL statements that perform poorly result in frustration for users, and can even prevent a company from serving its customers in a timely manner

Implementation of Quantum Private Queries Using Nuclear Magnetic Resonance

International Nuclear Information System (INIS)

Wang Chuan; Hao Liang; Zhao Lian-Jie

2011-01-01

We present a modified protocol for the realization of a quantum private query process on a classical database. Using one-qubit query and CNOT operation, the query process can be realized in a two-mode database. In the query process, the data privacy is preserved as the sender would not reveal any information about the database besides her query information, and the database provider cannot retain any information about the query. We implement the quantum private query protocol in a nuclear magnetic resonance system. The density matrix of the memory registers are constructed. (general)

Performance costs when emotion tunes inappropriate cognitive abilities: implications for mental resources and behavior.

Science.gov (United States)

Storbeck, Justin

2012-08-01

Emotion tunes cognition, such that approach-motivated positive states promote verbal cognition, whereas withdrawal-motivated negative states promote spatial cognition (Gray, 2001). The current research examined whether self-control resources become depleted and influence subsequent behavior when emotion tunes an inappropriate cognitive tendency. In 2 experiments, either an approach-motivated positive state or a withdrawal-motivated negative state was induced, and then participants completed a verbal or a spatial working memory task creating conditions of emotion-cognition alignment (e.g., approach/verbal) or misalignment (e.g., approach/spatial). A control condition was also included. To examine behavioral costs due to depleted self-control resources, participants completed either a Stroop task (Stroop, 1935; Experiment 1) or a Black/White implicit association test (IAT; Greenwald, McGhee, & Schwartz, 1998; Experiment 2). Participants in the misalignment conditions performed worse on the Stroop task, and they were worse at controlling their implicit attitude biases on the IAT. Thus, when emotion tunes inappropriate cognitive tendencies for one's current environment, self-control resources become depleted, impairing behavioral control. (PsycINFO Database Record (c) 2012 APA, all rights reserved).

Mobile Information Access with Spoken Query Answering

DEFF Research Database (Denmark)

Brøndsted, Tom; Larsen, Henrik Legind; Larsen, Lars Bo

2006-01-01

window focused over the part which most likely contains an answer to the query. The two systems are integrated into a full spoken query answering system. The prototype can answer queries and questions within the chosen football (soccer) test domain, but the system has the flexibility for being ported...

Effective Filtering of Query Results on Updated User Behavioral Profiles in Web Mining

Directory of Open Access Journals (Sweden)

S. Sadesh

2015-01-01

Full Text Available Web with tremendous volume of information retrieves result for user related queries. With the rapid growth of web page recommendation, results retrieved based on data mining techniques did not offer higher performance filtering rate because relationships between user profile and queries were not analyzed in an extensive manner. At the same time, existing user profile based prediction in web data mining is not exhaustive in producing personalized result rate. To improve the query result rate on dynamics of user behavior over time, Hamilton Filtered Regime Switching User Query Probability (HFRS-UQP framework is proposed. HFRS-UQP framework is split into two processes, where filtering and switching are carried out. The data mining based filtering in our research work uses the Hamilton Filtering framework to filter user result based on personalized information on automatic updated profiles through search engine. Maximized result is fetched, that is, filtered out with respect to user behavior profiles. The switching performs accurate filtering updated profiles using regime switching. The updating in profile change (i.e., switches regime in HFRS-UQP framework identifies the second- and higher-order association of query result on the updated profiles. Experiment is conducted on factors such as personalized information search retrieval rate, filtering efficiency, and precision ratio.

Responsive web design with jQuery

CERN Document Server

Carlos, Gilberto

2013-01-01

Responsive Web Design with jQuery follows a standard tutorial-based approach, covering various aspects of responsive web design by building a comprehensive website.""Responsive Web Design with jQuery"" is aimed at web designers who are interested in building device-agnostic websites. You should have a grasp of standard HTML, CSS, and JavaScript development, and have a familiarity with graphic design. Some exposure to jQuery and HTML5 will be beneficial but isn't essential.

SPARQL Assist language-neutral query composer

Science.gov (United States)

2012-01-01

Background SPARQL query composition is difficult for the lay-person, and even the experienced bioinformatician in cases where the data model is unfamiliar. Moreover, established best-practices and internationalization concerns dictate that the identifiers for ontological terms should be opaque rather than human-readable, which further complicates the task of synthesizing queries manually. Results We present SPARQL Assist: a Web application that addresses these issues by providing context-sensitive type-ahead completion during SPARQL query construction. Ontological terms are suggested using their multi-lingual labels and descriptions, leveraging existing support for internationalization and language-neutrality. Moreover, the system utilizes the semantics embedded in ontologies, and within the query itself, to help prioritize the most likely suggestions. Conclusions To ensure success, the Semantic Web must be easily available to all users, regardless of locale, training, or preferred language. By enhancing support for internationalization, and moreover by simplifying the manual construction of SPARQL queries through the use of controlled-natural-language interfaces, we believe we have made some early steps towards simplifying access to Semantic Web resources. PMID:22373327

SPARQL assist language-neutral query composer.

Science.gov (United States)

McCarthy, Luke; Vandervalk, Ben; Wilkinson, Mark

2012-01-25

SPARQL query composition is difficult for the lay-person, and even the experienced bioinformatician in cases where the data model is unfamiliar. Moreover, established best-practices and internationalization concerns dictate that the identifiers for ontological terms should be opaque rather than human-readable, which further complicates the task of synthesizing queries manually. We present SPARQL Assist: a Web application that addresses these issues by providing context-sensitive type-ahead completion during SPARQL query construction. Ontological terms are suggested using their multi-lingual labels and descriptions, leveraging existing support for internationalization and language-neutrality. Moreover, the system utilizes the semantics embedded in ontologies, and within the query itself, to help prioritize the most likely suggestions. To ensure success, the Semantic Web must be easily available to all users, regardless of locale, training, or preferred language. By enhancing support for internationalization, and moreover by simplifying the manual construction of SPARQL queries through the use of controlled-natural-language interfaces, we believe we have made some early steps towards simplifying access to Semantic Web resources.

Query Optimizations over Decentralized RDF Graphs

KAUST Repository

Abdelaziz, Ibrahim; Mansour, Essam; Ouzzani, Mourad; Aboulnaga, Ashraf; Kalnis, Panos

2017-01-01

Applications in life sciences, decentralized social networks, Internet of Things, and statistical linked dataspaces integrate data from multiple decentralized RDF graphs via SPARQL queries. Several approaches have been proposed to optimize query

Oracle SQL tuning with Oracle SQLTXPLAIN

CERN Document Server

Charalambides, Stelios

2013-01-01

Oracle SQL Tuning with SQLTXPLAIN is a practical guide to SQL tuning the way Oracle's own experts do it, using a freely downloadable tool called SQLTXPLAIN. Using this simple tool you'll learn how to tune even the most complex SQL, and you'll learn to do it quickly, without the huge learning curve usually associated with tuning as a whole.  Firmly based in real world problems, this book helps you reclaim system resources and avoid the most common bottleneck in overall performance, badly tuned SQL.  You'll learn how the optimizer works, how to take advantage of its latest features, and when it'

Design and evaluation of a NoSQL database for storing and querying RDF data

Directory of Open Access Journals (Sweden)

Kanda Runapongsa Saikaew

2014-12-01

Full Text Available Currently the amount of web data has increased excessively. Its metadata is widely used in order to fully exploit web information resources. This causes the need for Semantic Web technology to quickly analyze such big data. Resource Description Framework (RDF is a standard for describing web resources. In this paper, we propose a method to exploit a NoSQL database, specifically MongoDB, to store and query RDF data. We choose MongoDB to represent a NoSQL database because it is one of the most popular high-performance NoSQL databases. We evaluate the proposed design and implementation by using the Berlin SPARQL Benchmark, which is one of the most widely accepted benchmarks for comparing the performance of RDF storage systems. We compare three database systems, which are Apache Jena TDB (native RDF store, MySQL (relational database, and our proposed system with MongoDB (NoSQL database. Based on the experimental results analysis, our proposed system outperforms other database systems for most queries when the data set size is small. However, for a larger data set, MongoDB performs well for queries with simple operators while MySQL offers an efficient solution for complex queries. The result of this work can provide some guideline for choosing an appropriate RDF database system and applying a NoSQL database in storing and querying RDF data.

PERANGKAT BANTU UNTUK OPTIMASI QUERY PADA ORACLE DENGAN RESTRUKTURISASI SQL

Directory of Open Access Journals (Sweden)

Darlis Heru Murti

2006-07-01

Full Text Available Query merupakan bagian dari bahasa pemrograman SQL (Structured Query Language yang berfungsi untuk mengambil data (read dalam DBMS (Database Management System, termasuk Oracle [3]. Pada Oracle, ada tiga tahap proses yang dilakukan dalam pengeksekusian query, yaitu Parsing, Execute dan Fetch. Sebelum proses execute dijalankan, Oracle terlebih dahulu membuat execution plan yang akan menjadi skenario dalam proses excute.Dalam proses pengeksekusian query, terdapat faktor-faktor yang mempengaruhi kinerja query, di antaranya access path (cara pengambilan data dari sebuah tabel dan operasi join (cara menggabungkan data dari dua tabel. Untuk mendapatkan query dengan kinerja optimal, maka diperlukan pertimbangan-pertimbangan dalam menyikapi faktor-faktor tersebut.  Optimasi query merupakan suatu cara untuk mendapatkan query dengan kinerja seoptimal mungkin, terutama dilihat dari sudut pandang waktu. Ada banyak metode untuk mengoptimasi query, tapi pada Penelitian ini, penulis membuat sebuah aplikasi untuk mengoptimasi query dengan metode restrukturisasi SQL statement. Pada metode ini, objek yang dianalisa adalah struktur klausa yang membangun sebuah query. Aplikasi ini memiliki satu input dan lima jenis output. Input dari aplikasi ini adalah sebuah query sedangkan kelima jenis output aplikasi ini adalah berupa query hasil optimasi, saran perbaikan, saran pembuatan indeks baru, execution plan dan data statistik. Cara kerja aplikasi ini dibagi menjadi empat tahap yaitu mengurai query menjadi sub query, mengurai query per-klausa, menentukan access path dan operasi join dan restrukturisasi query.Dari serangkaian ujicoba yang dilakukan penulis, aplikasi telah dapat berjalan sesuai dengan tujuan pembuatan Penelitian ini, yaitu mendapatkan query dengan kinerja optimal.Kata Kunci : Query, SQL, DBMS, Oracle, Parsing, Execute, Fetch, Execution Plan, Access Path, Operasi Join, Restrukturisasi SQL statement.

NetMatchStar: an enhanced Cytoscape network querying app [version 1; referees: 2 approved

Directory of Open Access Journals (Sweden)

Fabio Rinnone

2015-08-01

Full Text Available We present NetMatchStar, a Cytoscape app to find all the occurrences of a query graph in a network and check for its significance as a motif with respect to seven different random models. The query can be uploaded or built from scratch using Cytoscape facilities. The app significantly enhances the previous NetMatch in style, performance and functionality. Notably NetMatchStar allows queries with wildcards.

Performance of the AC perpendicular biased ferrite tuned cavity for the TRIUMF KAON factory booster synchrotron

International Nuclear Information System (INIS)

Poirier, R.L.; Enchevich, I.B.; Mitra, A.K.; Fong, K.; Blaker, G.C.; Fang, S.

1992-11-01

The rf cavity for the Booster Synchrotron requires a frequency swing from 46 Mhz to 61 Mhz at a repetition rate of 50 Hz and a maximum accelerating voltage of 62.5 kV. These requirements were achieved on the prototype ferrite tuned cavity[1] for a short period of time and without any fast rf feedback or cavity tuning loops. Initially fast rf feedback and cavity tuning loops were closed at fixed frequencies (ferrite tuner dc biased ) to measure some of the response characteristics of the amplifier-cavity chain. Then a major effort was put into measuring the bandwidth response of the tuner in order to design the rf control loops for ac bias operation at 50 Hz. The performance of these control loops and results from long term running of the rf system are reported. (author) 3 refs., 5 figs

Code query by example

Science.gov (United States)

Vaucouleur, Sebastien

2011-02-01

We introduce code query by example for customisation of evolvable software products in general and of enterprise resource planning systems (ERPs) in particular. The concept is based on an initial empirical study on practices around ERP systems. We motivate our design choices based on those empirical results, and we show how the proposed solution helps with respect to the infamous upgrade problem: the conflict between the need for customisation and the need for upgrade of ERP systems. We further show how code query by example can be used as a form of lightweight static analysis, to detect automatically potential defects in large software products. Code query by example as a form of lightweight static analysis is particularly interesting in the context of ERP systems: it is often the case that programmers working in this field are not computer science specialists but more of domain experts. Hence, they require a simple language to express custom rules.

Fine tuning of work practices of common radiological investigations performed using computed radiography system

International Nuclear Information System (INIS)

Livingstone, Roshan S.; Timothy Peace, B.S.; Sunny, S.; Victor Raj, D.

2007-01-01

Introduction: The advent of the computed radiography (CR) has brought about remarkable changes in the field of diagnostic radiology. A relatively large cross-section of the human population is exposed to ionizing radiation on account of common radiological investigations. This study is intended to audit radiation doses imparted to patients during common radiological investigations involving the use of CR systems. Method: The entrance surface doses (ESD) were measured using thermoluminescent dosimeters (TLD) for various radiological investigations performed using the computed radiography (CR) systems. Optimization of radiographic techniques and radiation doses was done by fine tuning the work practices. Results and conclusion: Reduction of radiation doses as high as 47% was achieved during certain investigations with the use of optimized exposure factors and fine-tuned work practices

Efficient Approximate OLAP Querying Over Time Series

DEFF Research Database (Denmark)

Perera, Kasun Baruhupolage Don Kasun Sanjeewa; Hahmann, Martin; Lehner, Wolfgang

2016-01-01

The ongoing trend for data gathering not only produces larger volumes of data, but also increases the variety of recorded data types. Out of these, especially time series, e.g. various sensor readings, have attracted attention in the domains of business intelligence and decision making. As OLAP...... queries play a major role in these domains, it is desirable to also execute them on time series data. While this is not a problem on the conceptual level, it can become a bottleneck with regards to query run-time. In general, processing OLAP queries gets more computationally intensive as the volume...... of data grows. This is a particular problem when querying time series data, which generally contains multiple measures recorded at fine time granularities. Usually, this issue is addressed either by scaling up hardware or by employing workload based query optimization techniques. However, these solutions...

Flexible Query Answering Systems

DEFF Research Database (Denmark)

This book constitutes the refereed proceedings of the 10th International Conference on Flexible Query Answering Systems, FQAS 2013, held in Granada, Spain, in September 2013. The 59 full papers included in this volume were carefully reviewed and selected from numerous submissions. The papers...... are organized in a general session train and a parallel special session track. The general session train covers the following topics: querying-answering systems; semantic technology; patterns and classification; personalization and recommender systems; searching and ranking; and Web and human...

Algebraic Optimization of Recursive Database Queries

DEFF Research Database (Denmark)

Hansen, Michael Reichhardt

1988-01-01

Queries are expressed by relational algebra expressions including a fixpoint operation. A condition is presented under which a natural join commutes with a fixpoint operation. This condition is a simple check of attribute sets of sub-expressions of the query. The work may be considered a generali......Queries are expressed by relational algebra expressions including a fixpoint operation. A condition is presented under which a natural join commutes with a fixpoint operation. This condition is a simple check of attribute sets of sub-expressions of the query. The work may be considered...... a generalization of Aho and Ullman, (1979). The result is interpreted in function free logic database terms as a transformation of the recursively defined predicate involving: (a) elimination of an argument, and (b) propagation of selections (instantiations) to the extensionally defined predicates. A collection...

The effect of query complexity on Web searching results

Directory of Open Access Journals (Sweden)

B.J. Jansen

2000-01-01

Full Text Available This paper presents findings from a study of the effects of query structure on retrieval by Web search services. Fifteen queries were selected from the transaction log of a major Web search service in simple query form with no advanced operators (e.g., Boolean operators, phrase operators, etc. and submitted to 5 major search engines - Alta Vista, Excite, FAST Search, Infoseek, and Northern Light. The results from these queries became the baseline data. The original 15 queries were then modified using the various search operators supported by each of the 5 search engines for a total of 210 queries. Each of these 210 queries was also submitted to the applicable search service. The results obtained were then compared to the baseline results. A total of 2,768 search results were returned by the set of all queries. In general, increasing the complexity of the queries had little effect on the results with a greater than 70% overlap in results, on average. Implications for the design of Web search services and directions for future research are discussed.

Application of genetic algorithms to tuning fuzzy control systems

Science.gov (United States)

Espy, Todd; Vombrack, Endre; Aldridge, Jack

1993-01-01

Real number genetic algorithms (GA) were applied for tuning fuzzy membership functions of three controller applications. The first application is our 'Fuzzy Pong' demonstration, a controller that controls a very responsive system. The performance of the automatically tuned membership functions exceeded that of manually tuned membership functions both when the algorithm started with randomly generated functions and with the best manually-tuned functions. The second GA tunes input membership functions to achieve a specified control surface. The third application is a practical one, a motor controller for a printed circuit manufacturing system. The GA alters the positions and overlaps of the membership functions to accomplish the tuning. The applications, the real number GA approach, the fitness function and population parameters, and the performance improvements achieved are discussed. Directions for further research in tuning input and output membership functions and in tuning fuzzy rules are described.

GeoVanet: A Routing Protocol for Query Processing in Vehicular Networks

Directory of Open Access Journals (Sweden)

Thierry Delot

2011-01-01

Full Text Available In a vehicular ad hoc network (VANET, cars can exchange information by using short-range wireless communications. Along with the opportunities offered by vehicular networks, a number of challenges also arise. In particular, most works so far have focused on a push model, where potentially useful data are pushed towards vehicles. The use of pull models, that would allow users to send queries to a set of cars in order to find the desired information, has not been studied in depth. The main challenge for pull models is the difficulty to route the different results towards the query originator in a highly dynamic network where the nodes move very quickly. To solve this issue, we propose GeoVanet, an anonymous and non-intrusive geographic routing protocol which ensures that the sender of a query can get a consistent answer. Our goal is to ensure that the user will be able to retrieve the query results within a bounded time. To prove the effectiveness of GeoVanet, an extensive experimental evaluation has been performed, that proves the interest of the proposal for both rural and urban areas. It shows that up to 80% of the available query results are delivered to the user.

Mining the SDSS SkyServer SQL queries log

Science.gov (United States)

Hirota, Vitor M.; Santos, Rafael; Raddick, Jordan; Thakar, Ani

2016-05-01

SkyServer, the Internet portal for the Sloan Digital Sky Survey (SDSS) astronomic catalog, provides a set of tools that allows data access for astronomers and scientific education. One of SkyServer data access interfaces allows users to enter ad-hoc SQL statements to query the catalog. SkyServer also presents some template queries that can be used as basis for more complex queries. This interface has logged over 330 million queries submitted since 2001. It is expected that analysis of this data can be used to investigate usage patterns, identify potential new classes of queries, find similar queries, etc. and to shed some light on how users interact with the Sloan Digital Sky Survey data and how scientists have adopted the new paradigm of e-Science, which could in turn lead to enhancements on the user interfaces and experience in general. In this paper we review some approaches to SQL query mining, apply the traditional techniques used in the literature and present lessons learned, namely, that the general text mining approach for feature extraction and clustering does not seem to be adequate for this type of data, and, most importantly, we find that this type of analysis can result in very different queries being clustered together.

Fragger: a protein fragment picker for structural queries.

Science.gov (United States)

Berenger, Francois; Simoncini, David; Voet, Arnout; Shrestha, Rojan; Zhang, Kam Y J

2017-01-01

Protein modeling and design activities often require querying the Protein Data Bank (PDB) with a structural fragment, possibly containing gaps. For some applications, it is preferable to work on a specific subset of the PDB or with unpublished structures. These requirements, along with specific user needs, motivated the creation of a new software to manage and query 3D protein fragments. Fragger is a protein fragment picker that allows protein fragment databases to be created and queried. All fragment lengths are supported and any set of PDB files can be used to create a database. Fragger can efficiently search a fragment database with a query fragment and a distance threshold. Matching fragments are ranked by distance to the query. The query fragment can have structural gaps and the allowed amino acid sequences matching a query can be constrained via a regular expression of one-letter amino acid codes. Fragger also incorporates a tool to compute the backbone RMSD of one versus many fragments in high throughput. Fragger should be useful for protein design, loop grafting and related structural bioinformatics tasks.

GMB: An Efficient Query Processor for Biological Data

Directory of Open Access Journals (Sweden)

Taha Kamal

2011-06-01

Full Text Available Bioinformatics applications manage complex biological data stored into distributed and often heterogeneous databases and require large computing power. These databases are too big and complicated to be rapidly queried every time a user submits a query, due to the overhead involved in decomposing the queries, sending the decomposed queries to remote databases, and composing the results. There is also considerable communication costs involved. This study addresses the mentioned problems in Grid-based environment for bioinformatics. We propose a Grid middleware called GMB that alleviates these problems by caching the results of Frequently Used Queries (FUQ. Queries are classified based on their types and frequencies. FUQ are answered from the middleware, which improves their response time. GMB acts as a gateway to TeraGrid Grid: it resides between users’ applications and TeraGrid Grid. We evaluate GMB experimentally.

The Data Cyclotron query processing scheme

NARCIS (Netherlands)

Goncalves, R.; Kersten, M.

2011-01-01

A grand challenge of distributed query processing is to devise a self-organizing architecture which exploits all hardware resources optimally to manage the database hot set, minimize query response time, and maximize throughput without single point global coordination. The Data Cyclotron

Approximate furthest neighbor with application to annulus query

DEFF Research Database (Denmark)

Pagh, Rasmus; Silvestri, Francesco; Sivertsen, Johan von Tangen

2016-01-01

-dimensional Euclidean space. The method builds on the technique of Indyk (SODA 2003), storing random projections to provide sublinear query time for AFN. However, we introduce a different query algorithm, improving on Indyk׳s approximation factor and reducing the running time by a logarithmic factor. We also present......, the query-dependent approach is used for deriving a data structure for the approximate annulus query problem, which is defined as follows: given an input set S and two parameters r>0 and w≥1, construct a data structure that returns for each query point q a point p∈S such that the distance between p and q...

BioFed: federated query processing over life sciences linked open data.

Science.gov (United States)

Hasnain, Ali; Mehmood, Qaiser; Sana E Zainab, Syeda; Saleem, Muhammad; Warren, Claude; Zehra, Durre; Decker, Stefan; Rebholz-Schuhmann, Dietrich

2017-03-15

endpoint's availability based on the EndpointData graph. Our evaluation of BioFed against FedX is based on 20 heterogeneous federated SPARQL queries and shows competitive execution performance in comparison to FedX, which can be attributed to the provision of provenance information for the source selection. Developing and testing federated query engines for life sciences data is still a challenging task. According to our findings, it is advantageous to optimise the source selection. The cataloguing of SPARQL endpoints, including type and property indexing, leads to efficient querying of data resources over the Web of Data. This could even be further improved through the use of ontologies, e.g., for abstract normalisation of query terms.

Manchester visual query language

Science.gov (United States)

Oakley, John P.; Davis, Darryl N.; Shann, Richard T.

1993-04-01

We report a database language for visual retrieval which allows queries on image feature information which has been computed and stored along with images. The language is novel in that it provides facilities for dealing with feature data which has actually been obtained from image analysis. Each line in the Manchester Visual Query Language (MVQL) takes a set of objects as input and produces another, usually smaller, set as output. The MVQL constructs are mainly based on proven operators from the field of digital image analysis. An example is the Hough-group operator which takes as input a specification for the objects to be grouped, a specification for the relevant Hough space, and a definition of the voting rule. The output is a ranked list of high scoring bins. The query could be directed towards one particular image or an entire image database, in the latter case the bins in the output list would in general be associated with different images. We have implemented MVQL in two layers. The command interpreter is a Lisp program which maps each MVQL line to a sequence of commands which are used to control a specialized database engine. The latter is a hybrid graph/relational system which provides low-level support for inheritance and schema evolution. In the paper we outline the language and provide examples of useful queries. We also describe our solution to the engineering problems associated with the implementation of MVQL.

RDF-GL: A SPARQL-Based Graphical Query Language for RDF

Science.gov (United States)

Hogenboom, Frederik; Milea, Viorel; Frasincar, Flavius; Kaymak, Uzay

This chapter presents RDF-GL, a graphical query language (GQL) for RDF. The GQL is based on the textual query language SPARQL and mainly focuses on SPARQL SELECT queries. The advantage of a GQL over textual query languages is that complexity is hidden through the use of graphical symbols. RDF-GL is supported by a Java-based editor, SPARQLinG, which is presented as well. The editor does not only allow for RDF-GL query creation, but also converts RDF-GL queries to SPARQL queries and is able to subsequently execute these. Experiments show that using the GQL in combination with the editor makes RDF querying more accessible for end users.

The Data Cyclotron query processing scheme.

NARCIS (Netherlands)

R.A. Goncalves (Romulo); M.L. Kersten (Martin)

2011-01-01

htmlabstractA grand challenge of distributed query processing is to devise a self-organizing architecture which exploits all hardware resources optimally to manage the database hot set, minimize query response time, and maximize throughput without single point global coordination. The Data Cyclotron

A Multi-Query Optimizer for Monet

NARCIS (Netherlands)

S. Manegold (Stefan); A.J. Pellenkoft (Jan); M.L. Kersten (Martin)

2000-01-01

textabstractDatabase systems allow for concurrent use of several applications (and query interfaces). Each application generates an ``optimal'' plan---a sequence of low-level database operators---for accessing the database. The queries posed by users through the same application can be optimized

A multi-query optimizer for Monet

NARCIS (Netherlands)

S. Manegold (Stefan); A.J. Pellenkoft (Jan); M.L. Kersten (Martin)

2000-01-01

textabstractDatabase systems allow for concurrent use of several applications (and query interfaces). Each application generates an ``optimal'' plan---a sequence of low-level database operators---for accessing the database. The queries posed by users through the same application can be optimized

Result Diversification Based on Query-Specific Cluster Ranking

NARCIS (Netherlands)

J. He (Jiyin); E. Meij; M. de Rijke (Maarten)

2011-01-01

htmlabstractResult diversification is a retrieval strategy for dealing with ambiguous or multi-faceted queries by providing documents that cover as many facets of the query as possible. We propose a result diversification framework based on query-specific clustering and cluster ranking,

Visual Querying in Chemical Databases using SMARTS Patterns

OpenAIRE

Šípek, Vojtěch

2014-01-01

The purpose of this thesis is to create framework for visual querying in chemical databases which will be implemented as a web application. By using graphical editor, which is a part of client side, the user creates queries which are translated into chemical query language SMARTS. This query is parsed on the application server which is connected to the chemical database. This framework also contains tooling for creating the database and index structure above it. 1

FTree query construction for virtual screening: a statistical analysis.

Science.gov (United States)

Gerlach, Christof; Broughton, Howard; Zaliani, Andrea

2008-02-01

FTrees (FT) is a known chemoinformatic tool able to condense molecular descriptions into a graph object and to search for actives in large databases using graph similarity. The query graph is classically derived from a known active molecule, or a set of actives, for which a similar compound has to be found. Recently, FT similarity has been extended to fragment space, widening its capabilities. If a user were able to build a knowledge-based FT query from information other than a known active structure, the similarity search could be combined with other, normally separate, fields like de-novo design or pharmacophore searches. With this aim in mind, we performed a comprehensive analysis of several databases in terms of FT description and provide a basic statistical analysis of the FT spaces so far at hand. Vendors' catalogue collections and MDDR as a source of potential or known "actives", respectively, have been used. With the results reported herein, a set of ranges, mean values and standard deviations for several query parameters are presented in order to set a reference guide for the users. Applications on how to use this information in FT query building are also provided, using a newly built 3D-pharmacophore from 57 5HT-1F agonists and a published one which was used for virtual screening for tRNA-guanine transglycosylase (TGT) inhibitors.

Result diversification based on query-specific cluster ranking

NARCIS (Netherlands)

He, J.; Meij, E.; de Rijke, M.

2011-01-01

Result diversification is a retrieval strategy for dealing with ambiguous or multi-faceted queries by providing documents that cover as many facets of the query as possible. We propose a result diversification framework based on query-specific clustering and cluster ranking, in which diversification

MOCQL: A Declarative Language for Ad-Hoc Model Querying

DEFF Research Database (Denmark)

Störrle, Harald

2013-01-01

Language (MOCQL), an experimental declarative textual language to express queries (and constraints) on models. We introduce MOCQL by examples and its grammar, evaluate its usability by means of controlled experiments, and find that modelers perform better and experience less cognitive load when working...

An Efficient Algorithm for Maximizing Range Sum Queries in a Road Network

Directory of Open Access Journals (Sweden)

Tien-Khoi Phan

2014-01-01

Full Text Available Given a set of positive-weighted points and a query rectangle r (specified by a client of given extents, the goal of a maximizing range sum (MaxRS query is to find the optimal location of r such that the total weights of all the points covered by r are maximized. All existing methods for processing MaxRS queries assume the Euclidean distance metric. In many location-based applications, however, the motion of a client may be constrained by an underlying (spatial road network; that is, the client cannot move freely in space. This paper addresses the problem of processing MaxRS queries in a road network. We propose the external-memory algorithm that is suited for a large road network database. In addition, in contrast to the existing methods, which retrieve only one optimal location, our proposed algorithm retrieves all the possible optimal locations. Through simulations, we evaluate the performance of the proposed algorithm.

Optimizing Cost of Continuous Overlapping Queries over Data Streams by Filter Adaption

KAUST Repository

Xie, Qing

2016-01-12

The problem we aim to address is the optimization of cost management for executing multiple continuous queries on data streams, where each query is defined by several filters, each of which monitors certain status of the data stream. Specially the filter can be shared by different queries and expensive to evaluate. The conventional objective for such a problem is to minimize the overall execution cost to solve all queries, by planning the order of filter evaluation in shared strategy. However, in streaming scenario, the characteristics of data items may change in process, which can bring some uncertainty to the outcome of individual filter evaluation, and affect the plan of query execution as well as the overall execution cost. In our work, considering the influence of the uncertain variation of data characteristics, we propose a framework to deal with the dynamic adjustment of filter ordering for query execution on data stream, and focus on the issues of cost management. By incrementally monitoring and analyzing the results of filter evaluation, our proposed approach can be effectively adaptive to the varied stream behavior and adjust the optimal ordering of filter evaluation, so as to optimize the execution cost. In order to achieve satisfactory performance and efficiency, we also discuss the trade-off between the adaptivity of our framework and the overhead incurred by filter adaption. The experimental results on synthetic and two real data sets (traffic and multimedia) show that our framework can effectively reduce and balance the overall query execution cost and keep high adaptivity in streaming scenario.

Cumulative query method for influenza surveillance using search engine data.

Science.gov (United States)

Seo, Dong-Woo; Jo, Min-Woo; Sohn, Chang Hwan; Shin, Soo-Yong; Lee, JaeHo; Yu, Maengsoo; Kim, Won Young; Lim, Kyoung Soo; Lee, Sang-Il

2014-12-16

Internet search queries have become an important data source in syndromic surveillance system. However, there is currently no syndromic surveillance system using Internet search query data in South Korea. The objective of this study was to examine correlations between our cumulative query method and national influenza surveillance data. Our study was based on the local search engine, Daum (approximately 25% market share), and influenza-like illness (ILI) data from the Korea Centers for Disease Control and Prevention. A quota sampling survey was conducted with 200 participants to obtain popular queries. We divided the study period into two sets: Set 1 (the 2009/10 epidemiological year for development set 1 and 2010/11 for validation set 1) and Set 2 (2010/11 for development Set 2 and 2011/12 for validation Set 2). Pearson's correlation coefficients were calculated between the Daum data and the ILI data for the development set. We selected the combined queries for which the correlation coefficients were .7 or higher and listed them in descending order. Then, we created a cumulative query method n representing the number of cumulative combined queries in descending order of the correlation coefficient. In validation set 1, 13 cumulative query methods were applied, and 8 had higher correlation coefficients (min=.916, max=.943) than that of the highest single combined query. Further, 11 of 13 cumulative query methods had an r value of ≥.7, but 4 of 13 combined queries had an r value of ≥.7. In validation set 2, 8 of 15 cumulative query methods showed higher correlation coefficients (min=.975, max=.987) than that of the highest single combined query. All 15 cumulative query methods had an r value of ≥.7, but 6 of 15 combined queries had an r value of ≥.7. Cumulative query method showed relatively higher correlation with national influenza surveillance data than combined queries in the development and validation set.

Query Health: standards-based, cross-platform population health surveillance.

Science.gov (United States)

Klann, Jeffrey G; Buck, Michael D; Brown, Jeffrey; Hadley, Marc; Elmore, Richard; Weber, Griffin M; Murphy, Shawn N

2014-01-01

Understanding population-level health trends is essential to effectively monitor and improve public health. The Office of the National Coordinator for Health Information Technology (ONC) Query Health initiative is a collaboration to develop a national architecture for distributed, population-level health queries across diverse clinical systems with disparate data models. Here we review Query Health activities, including a standards-based methodology, an open-source reference implementation, and three pilot projects. Query Health defined a standards-based approach for distributed population health queries, using an ontology based on the Quality Data Model and Consolidated Clinical Document Architecture, Health Quality Measures Format (HQMF) as the query language, the Query Envelope as the secure transport layer, and the Quality Reporting Document Architecture as the result language. We implemented this approach using Informatics for Integrating Biology and the Bedside (i2b2) and hQuery for data analytics and PopMedNet for access control, secure query distribution, and response. We deployed the reference implementation at three pilot sites: two public health departments (New York City and Massachusetts) and one pilot designed to support Food and Drug Administration post-market safety surveillance activities. The pilots were successful, although improved cross-platform data normalization is needed. This initiative resulted in a standards-based methodology for population health queries, a reference implementation, and revision of the HQMF standard. It also informed future directions regarding interoperability and data access for ONC's Data Access Framework initiative. Query Health was a test of the learning health system that supplied a functional methodology and reference implementation for distributed population health queries that has been validated at three sites. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under

Estimating Influenza Outbreaks Using Both Search Engine Query Data and Social Media Data in South Korea.

Science.gov (United States)

Woo, Hyekyung; Cho, Youngtae; Shim, Eunyoung; Lee, Jong-Koo; Lee, Chang-Gun; Kim, Seong Hwan

2016-07-04

As suggested as early as in 2006, logs of queries submitted to search engines seeking information could be a source for detection of emerging influenza epidemics if changes in the volume of search queries are monitored (infodemiology). However, selecting queries that are most likely to be associated with influenza epidemics is a particular challenge when it comes to generating better predictions. In this study, we describe a methodological extension for detecting influenza outbreaks using search query data; we provide a new approach for query selection through the exploration of contextual information gleaned from social media data. Additionally, we evaluate whether it is possible to use these queries for monitoring and predicting influenza epidemics in South Korea. Our study was based on freely available weekly influenza incidence data and query data originating from the search engine on the Korean website Daum between April 3, 2011 and April 5, 2014. To select queries related to influenza epidemics, several approaches were applied: (1) exploring influenza-related words in social media data, (2) identifying the chief concerns related to influenza, and (3) using Web query recommendations. Optimal feature selection by least absolute shrinkage and selection operator (Lasso) and support vector machine for regression (SVR) were used to construct a model predicting influenza epidemics. In total, 146 queries related to influenza were generated through our initial query selection approach. A considerable proportion of optimal features for final models were derived from queries with reference to the social media data. The SVR model performed well: the prediction values were highly correlated with the recent observed influenza-like illness (r=.956; Psearch queries to enhance influenza surveillance in South Korea. In addition, an approach for query selection using social media data seems ideal for supporting influenza surveillance based on search query data.

Managing and Querying Image Annotation and Markup in XML.

Science.gov (United States)

Wang, Fusheng; Pan, Tony; Sharma, Ashish; Saltz, Joel

2010-01-01

Proprietary approaches for representing annotations and image markup are serious barriers for researchers to share image data and knowledge. The Annotation and Image Markup (AIM) project is developing a standard based information model for image annotation and markup in health care and clinical trial environments. The complex hierarchical structures of AIM data model pose new challenges for managing such data in terms of performance and support of complex queries. In this paper, we present our work on managing AIM data through a native XML approach, and supporting complex image and annotation queries through native extension of XQuery language. Through integration with xService, AIM databases can now be conveniently shared through caGrid.

Managing and Querying Image Annotation and Markup in XML

Science.gov (United States)

Wang, Fusheng; Pan, Tony; Sharma, Ashish; Saltz, Joel

2010-01-01

Proprietary approaches for representing annotations and image markup are serious barriers for researchers to share image data and knowledge. The Annotation and Image Markup (AIM) project is developing a standard based information model for image annotation and markup in health care and clinical trial environments. The complex hierarchical structures of AIM data model pose new challenges for managing such data in terms of performance and support of complex queries. In this paper, we present our work on managing AIM data through a native XML approach, and supporting complex image and annotation queries through native extension of XQuery language. Through integration with xService, AIM databases can now be conveniently shared through caGrid. PMID:21218167

A general approach to query flattening

NARCIS (Netherlands)

van Ruth, J.

The translation of queries from complex data models to simpler data models is a recurring theme in the construction of efficient data management systems. In this paper we propose a general framework to guide the translation from data models with nested types to a flat relational model (query

Exploiting External Collections for Query Expansion

NARCIS (Netherlands)

Weerkamp, W.; Balog, K.; de Rijke, M.

2012-01-01

A persisting challenge in the field of information retrieval is the vocabulary mismatch between a user’s information need and the relevant documents. One way of addressing this issue is to apply query modeling: to add terms to the original query and reweigh the terms. In social media, where

Control of Fermilab Booster tunes

International Nuclear Information System (INIS)

Johnson, R.P; Meisner, K.; Sandberg, B.

1977-01-01

Control of the radial and vertical tunes of the booster is implemented using ramped correction quadrupoles. Minor modifications to the power supply cards for the 48 (previously) dc correction quadrupoles allow ''the tunes'' to be continuously programmed or held constant throughout the 33 ms acceleration cycle. This capability is in addition to the usual use of these quadrupoles to be independently varied to correct for harmonic distortions in the lattice. An automatic computer program measures and displays the tunes vs. time in the cycle to monitor performance and to allow the ramps to be adjusted by the machine operator

Sonata: Query-Driven Network Telemetry

KAUST Repository

Gupta, Arpit; Harrison, Rob; Pawar, Ankita; Birkner, Rü diger; Canini, Marco; Feamster, Nick; Rexford, Jennifer; Willinger, Walter

2017-01-01

Operating networks depends on collecting and analyzing measurement data. Current technologies do not make it easy to do so, typically because they separate data collection (e.g., packet capture or flow monitoring) from analysis, producing either too much data to answer a general question or too little data to answer a detailed question. In this paper, we present Sonata, a network telemetry system that uses a uniform query interface to drive the joint collection and analysis of network traffic. Sonata takes the advantage of two emerging technologies---streaming analytics platforms and programmable network devices---to facilitate joint collection and analysis. Sonata allows operators to more directly express network traffic analysis tasks in terms of a high-level language. The underlying runtime partitions each query into a portion that runs on the switch and another that runs on the streaming analytics platform iteratively refines the query to efficiently capture only the traffic that pertains to the operator's query, and exploits sketches to reduce state in switches in exchange for more approximate results. Through an evaluation of a prototype implementation, we demonstrate that Sonata can support a wide range of network telemetry tasks with less state in the network, and lower data rates to streaming analytics systems, than current approaches can achieve.

Sonata: Query-Driven Network Telemetry

KAUST Repository

Gupta, Arpit

2017-05-02

Operating networks depends on collecting and analyzing measurement data. Current technologies do not make it easy to do so, typically because they separate data collection (e.g., packet capture or flow monitoring) from analysis, producing either too much data to answer a general question or too little data to answer a detailed question. In this paper, we present Sonata, a network telemetry system that uses a uniform query interface to drive the joint collection and analysis of network traffic. Sonata takes the advantage of two emerging technologies---streaming analytics platforms and programmable network devices---to facilitate joint collection and analysis. Sonata allows operators to more directly express network traffic analysis tasks in terms of a high-level language. The underlying runtime partitions each query into a portion that runs on the switch and another that runs on the streaming analytics platform iteratively refines the query to efficiently capture only the traffic that pertains to the operator\\'s query, and exploits sketches to reduce state in switches in exchange for more approximate results. Through an evaluation of a prototype implementation, we demonstrate that Sonata can support a wide range of network telemetry tasks with less state in the network, and lower data rates to streaming analytics systems, than current approaches can achieve.

A web-based data-querying tool based on ontology-driven methodology and flowchart-based model.

Science.gov (United States)

Ping, Xiao-Ou; Chung, Yufang; Tseng, Yi-Ju; Liang, Ja-Der; Yang, Pei-Ming; Huang, Guan-Tarn; Lai, Feipei

2013-10-08

Because of the increased adoption rate of electronic medical record (EMR) systems, more health care records have been increasingly accumulating in clinical data repositories. Therefore, querying the data stored in these repositories is crucial for retrieving the knowledge from such large volumes of clinical data. The aim of this study is to develop a Web-based approach for enriching the capabilities of the data-querying system along the three following considerations: (1) the interface design used for query formulation, (2) the representation of query results, and (3) the models used for formulating query criteria. The Guideline Interchange Format version 3.5 (GLIF3.5), an ontology-driven clinical guideline representation language, was used for formulating the query tasks based on the GLIF3.5 flowchart in the Protégé environment. The flowchart-based data-querying model (FBDQM) query execution engine was developed and implemented for executing queries and presenting the results through a visual and graphical interface. To examine a broad variety of patient data, the clinical data generator was implemented to automatically generate the clinical data in the repository, and the generated data, thereby, were employed to evaluate the system. The accuracy and time performance of the system for three medical query tasks relevant to liver cancer were evaluated based on the clinical data generator in the experiments with varying numbers of patients. In this study, a prototype system was developed to test the feasibility of applying a methodology for building a query execution engine using FBDQMs by formulating query tasks using the existing GLIF. The FBDQM-based query execution engine was used to successfully retrieve the clinical data based on the query tasks formatted using the GLIF3.5 in the experiments with varying numbers of patients. The accuracy of the three queries (ie, "degree of liver damage," "degree of liver damage when applying a mutually exclusive setting

Automatic tuning of free electron lasers

Energy Technology Data Exchange (ETDEWEB)

Agapov, Ilya; Zagorodnov, Igor [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Geloni, Gianluca [European XFEL, Schenefeld (Germany); Tomin, Sergey [European XFEL, Schenefeld (Germany); NRC Kurchatov Institute, Moscow (Russian Federation)

2017-04-07

Existing FEL facilities often suffer from stability issues: so electron orbit, transverse electron optics, electron bunch compression and other parameters have to be readjusted often to account for drifts in performance of various components. The tuning procedures typically employed in operation are often manual and lengthy. We have been developing a combination of model-free and model-based automatic tuning methods to meet the needs of present and upcoming XFEL facilities. Our approach has been implemented at FLASH to achieve automatic SASE tuning using empirical control of orbit, electron optics and bunch compression. In this paper we describe our approach to empirical tuning, the software which implements it, and the results of using it at FLASH.We also discuss the potential of using machine learning and model-based techniques in tuning methods.

Automatic tuning of free electron lasers

International Nuclear Information System (INIS)

Agapov, Ilya; Zagorodnov, Igor; Geloni, Gianluca; Tomin, Sergey

2017-01-01

Existing FEL facilities often suffer from stability issues: so electron orbit, transverse electron optics, electron bunch compression and other parameters have to be readjusted often to account for drifts in performance of various components. The tuning procedures typically employed in operation are often manual and lengthy. We have been developing a combination of model-free and model-based automatic tuning methods to meet the needs of present and upcoming XFEL facilities. Our approach has been implemented at FLASH to achieve automatic SASE tuning using empirical control of orbit, electron optics and bunch compression. In this paper we describe our approach to empirical tuning, the software which implements it, and the results of using it at FLASH.We also discuss the potential of using machine learning and model-based techniques in tuning methods.

DBPQL: A view-oriented query language for the Intel Data Base Processor

Science.gov (United States)

Fishwick, P. A.

1983-01-01

An interactive query language (BDPQL) for the Intel Data Base Processor (DBP) is defined. DBPQL includes a parser generator package which permits the analyst to easily create and manipulate the query statement syntax and semantics. The prototype language, DBPQL, includes trace and performance commands to aid the analyst when implementing new commands and analyzing the execution characteristics of the DBP. The DBPQL grammar file and associated key procedures are included as an appendix to this report.

Applying GA for Optimizing the User Query in Image and Video Retrieval

OpenAIRE

Ehsan Lotfi

2014-01-01

In an information retrieval system, the query can be made by user sketch. The new method presented here, optimizes the user sketch and applies the optimized query to retrieval the information. This optimization may be used in Content-Based Image Retrieval (CBIR) and Content-Based Video Retrieval (CBVR) which is based on trajectory extraction. To optimize the retrieval process, one stage of retrieval is performed by the user sketch. The retrieval criterion is based on the proposed distance met...

jQuery Mobile Up and Running

CERN Document Server

Firtman, Maximiliano

2012-01-01

Would you like to build one mobile web application that works on iPad and Kindle Fire as well as iPhone and Android smartphones? This introductory guide to jQuery Mobile shows you how. Through a series of hands-on exercises, you'll learn the best ways to use this framework's many interface components to build customizable, multiplatform apps. You don't need any programming skills or previous experience with jQuery to get started. By the time you finish this book, you'll know how to create responsive, Ajax-based interfaces that work on a variety of smartphones and tablets, using jQuery Mobile

jQuery for designers beginner's guide

CERN Document Server

MacLees, Natalie

2014-01-01

A step-by-step guide that spices up your web pages and designs them in the way you want using the most widely used JavaScript library, jQuery. The beginner-friendly and easy-to-understand approach of the book will help get to grips with jQuery in no time. If you know the fundamentals of HTML and CSS, and want to extend your knowledge by learning to use JavaScript, then this is just the book for you. jQuery makes JavaScript straightforward and approachable - you'll be surprised at how easy it can be to add animations and special effects to your beautifully designed pages.

Querying Business Process Models with VMQL

DEFF Research Database (Denmark)

Störrle, Harald; Acretoaie, Vlad

2013-01-01

The Visual Model Query Language (VMQL) has been invented with the objectives (1) to make it easier for modelers to query models effectively, and (2) to be universally applicable to all modeling languages. In previous work, we have applied VMQL to UML, and validated the first of these two claims. ...

Does query expansion limit our learning? A comparison of social-based expansion to content-based expansion for medical queries on the internet.

Science.gov (United States)

Pentoney, Christopher; Harwell, Jeff; Leroy, Gondy

2014-01-01

Searching for medical information online is a common activity. While it has been shown that forming good queries is difficult, Google's query suggestion tool, a type of query expansion, aims to facilitate query formation. However, it is unknown how this expansion, which is based on what others searched for, affects the information gathering of the online community. To measure the impact of social-based query expansion, this study compared it with content-based expansion, i.e., what is really in the text. We used 138,906 medical queries from the AOL User Session Collection and expanded them using Google's Autocomplete method (social-based) and the content of the Google Web Corpus (content-based). We evaluated the specificity and ambiguity of the expansion terms for trigram queries. We also looked at the impact on the actual results using domain diversity and expansion edit distance. Results showed that the social-based method provided more precise expansion terms as well as terms that were less ambiguous. Expanded queries do not differ significantly in diversity when expanded using the social-based method (6.72 different domains returned in the first ten results, on average) vs. content-based method (6.73 different domains, on average).

Query by example video based on fuzzy c-means initialized by fixed clustering center

Science.gov (United States)

Hou, Sujuan; Zhou, Shangbo; Siddique, Muhammad Abubakar

2012-04-01

Currently, the high complexity of video contents has posed the following major challenges for fast retrieval: (1) efficient similarity measurements, and (2) efficient indexing on the compact representations. A video-retrieval strategy based on fuzzy c-means (FCM) is presented for querying by example. Initially, the query video is segmented and represented by a set of shots, each shot can be represented by a key frame, and then we used video processing techniques to find visual cues to represent the key frame. Next, because the FCM algorithm is sensitive to the initializations, here we initialized the cluster center by the shots of query video so that users could achieve appropriate convergence. After an FCM cluster was initialized by the query video, each shot of query video was considered a benchmark point in the aforesaid cluster, and each shot in the database possessed a class label. The similarity between the shots in the database with the same class label and benchmark point can be transformed into the distance between them. Finally, the similarity between the query video and the video in database was transformed into the number of similar shots. Our experimental results demonstrated the performance of this proposed approach.

Reformulating XQuery queries using GLAV mapping and complex unification

Directory of Open Access Journals (Sweden)

Saber Benharzallah

2016-01-01

Full Text Available This paper describes an algorithm for reformulation of XQuery queries. The mediation is based on an essential component called mediator. Its main role is to reformulate a user query, written in terms of global schema, into queries written in terms of source schemas. Our algorithm is based on the principle of logical equivalence, simple and complex unification, to obtain a better reformulation. It takes XQuery query, global schema (written in XMLSchema, and mappings GLAV as input parameters and provides resultant query written in terms of source schemas. The results of implementation show the proper functioning of the algorithm.

Query transformations and their role in Web searching by the members of the general public

Directory of Open Access Journals (Sweden)

Martin Whittle

2006-01-01

Full Text Available Introduction. This paper reports preliminary research in a primarily experimental study of how the general public search for information on the Web. The focus is on the query transformation patterns that characterise searching. Method. In this work, we have used transaction logs from the Excite search engine to develop methods for analysing query transformations that should aid the analysis of our ongoing experimental work. Our methods involve the use of similarity techniques to link queries with the most similar previous query in a train. The resulting query transformations are represented as a list of codes representing a whole search. Analysis. It is shown how query transformation sequences can be represented as graphical networks and some basic statistical results are shown. A correlation analysis is performed to examine the co-occurrence of Boolean and quotation mark changes with the syntactic changes. Results. A frequency analysis of the occurrence of query transformation codes is presented. The connectivity of graphs obtained from the query transformation is investigated and found to follow an exponential scaling law. The correlation analysis reveals a number of patterns that provide some interesting insights into Web searching by the general public. Conclusion. We have developed analytical methods based on query similarity that can be applied to our current experimental work with volunteer subjects. The results of these will form part of a database with the aim of developing an improved understanding of how the public search the Web.

Towards Optimal Multi-Dimensional Query Processing with BitmapIndices

Energy Technology Data Exchange (ETDEWEB)

Rotem, Doron; Stockinger, Kurt; Wu, Kesheng

2005-09-30

Bitmap indices have been widely used in scientific applications and commercial systems for processing complex, multi-dimensional queries where traditional tree-based indices would not work efficiently. This paper studies strategies for minimizing the access costs for processing multi-dimensional queries using bitmap indices with binning. Innovative features of our algorithm include (a) optimally placing the bin boundaries and (b) dynamically reordering the evaluation of the query terms. In addition, we derive several analytical results concerning optimal bin allocation for a probabilistic query model. Our experimental evaluation with real life data shows an average I/O cost improvement of at least a factor of 10 for multi-dimensional queries on datasets from two different applications. Our experiments also indicate that the speedup increases with the number of query dimensions.

AQBE — QBE Style Queries for Archetyped Data

Science.gov (United States)

Sachdeva, Shelly; Yaginuma, Daigo; Chu, Wanming; Bhalla, Subhash

Large-scale adoption of electronic healthcare applications requires semantic interoperability. The new proposals propose an advanced (multi-level) DBMS architecture for repository services for health records of patients. These also require query interfaces at multiple levels and at the level of semi-skilled users. In this regard, a high-level user interface for querying the new form of standardized Electronic Health Records system has been examined in this study. It proposes a step-by-step graphical query interface to allow semi-skilled users to write queries. Its aim is to decrease user effort and communication ambiguities, and increase user friendliness.

Group-by Skyline Query Processing in Relational Engines

DEFF Research Database (Denmark)

Yiu, Man Lung; Luk, Ming-Hay; Lo, Eric

2009-01-01

the missing cost model for the BBS algorithm. Experimental results show that our techniques are able to devise the best query plans for a variety of group-by skyline queries. Our focus is on algorithms that can be directly implemented in today's commercial database systems without the addition of new access......The skyline operator was first proposed in 2001 for retrieving interesting tuples from a dataset. Since then, 100+ skyline-related papers have been published; however, we discovered that one of the most intuitive and practical type of skyline queries, namely, group-by skyline queries remains...

An Efficient Data Fingerprint Query Algorithm Based on Two-Leveled Bloom Filter

OpenAIRE

Bin Zhou; Rongbo Zhu; Ying Zhang; Linhui Cheng

2013-01-01

The function of the comparing fingerprints algorithm was to judge whether a new partitioned data chunk was in a storage system a decade ago.  At present, in the most de-duplication backup system the fingerprints of the big data chunks are huge and cannot be stored in the memory completely. The performance of the system is unavoidably retarded by data chunks accessing the storage system at the querying stage. Accordingly, a new query mechanism namely Two-stage Bloom Filter (TBF) mechanism...

Head First jQuery

CERN Document Server

Benedetti, Ryan

2011-01-01

Want to add more interactivity and polish to your websites? Discover how jQuery can help you build complex scripting functionality in just a few lines of code. With Head First jQuery, you'll quickly get up to speed on this amazing JavaScript library by learning how to navigate HTML documents while handling events, effects, callbacks, and animations. By the time you've completed the book, you'll be incorporating Ajax apps, working seamlessly with HTML and CSS, and handling data with PHP, MySQL and JSON. If you want to learn-and understand-how to create interactive web pages, unobtrusive scrip

Comparison of the Efficiency of Tuned Mass and Tuned Liquid Dampers at High-Rise Structures under Near and Far Fault Earthquakes

Directory of Open Access Journals (Sweden)

Hamed Rahman Shokrgozar

2017-02-01

Full Text Available Tuned mass and tuned liquid dampers are most common passive control systems that used for decrease of seismic responses of buildings. In this study, the performance of high-rise buildings with TM and TL dampers are evaluated under seven near-fault and seven far-fault earthquakes. For this purpose, a twenty-four stories steel moment frame building has been considered and the time history dynamic analyses are performed for both of controlled and uncontrolled states. Moreover, this building has been also modelled with five various mass, stiffness and damping ratios.The results have been shown that decreasing the structural responses at tall buildings against near-fault earthquakes are more than far-fault earthquakes due to the effect of higher modes. Furthermore, the tuned mass damper has better performance at decreasing of the responses in comparison of tuned liquid dampers.

Historic Learning Approach for Auto-tuning OpenACC Accelerated Scientific Applications

KAUST Repository

Siddiqui, Shahzeb

2015-04-17

The performance optimization of scientific applications usually requires an in-depth knowledge of the hardware and software. A performance tuning mechanism is suggested to automatically tune OpenACC parameters to adapt to the execution environment on a given system. A historic learning based methodology is suggested to prune the parameter search space for a more efficient auto-tuning process. This approach is applied to tune the OpenACC gang and vector clauses for a better mapping of the compute kernels onto the underlying architecture. Our experiments show a significant performance improvement against the default compiler parameters and drastic reduction in tuning time compared to a brute force search-based approach.

ALGORITMA RC4 DALAM PROTEKSI TRANSMISI DAN HASIL QUERY UNTUK ORDBMS POSTGRESQL

Directory of Open Access Journals (Sweden)

Yuri Ariyanto

2009-01-01

Full Text Available In this research will be worked through about how cryptography RC4's algorithm implementation in protection to query result and of query, security by encryption and descryption up to both is in network. Implementation of this research which is build software in client that function access databases that is placed by the side of server. Software that building to have facility for encryption and descryption query result and of query that is sent from client goes to server and. transmission query result and of query can secure its security. Well guaranted transmission security him of query result and of query can be told to succeed if success software can encryption query result and of query which transmission so that in the event of scanning to both, scanning will not understand data content. Conclusion of this research that is woke up software succeed encryption query and result of query which transmission between application of client and of server databases. Abstract in Bahasa Indonesia: Pada penelitian ini dibahas mengenai bagaimana mengimplementasikan algoritma kriptografi RC4 dalam proteksi terhadap query dan hasil query, pengamanan dilakukan dengan cara melakukan enkripsi dan dekripsi selama keduanya berada di dalam jaringan. Pengimplementasian dari penelitian ini yaitu membangun sebuah software yang akan diletakkan di sisi client yang berfungsi mengakses database yang diletakkan di sisi server. Software yang dibangun memiliki fasilitas untuk mengenkripsi dan mendektipsi query dan hasil query yang dikirimkan dari client ke server dan juga sebaliknya. Dengan demikian tramsmisi query dan hasil query dapat terjamin keamanannya.Terjaminnya keamanan transmisi query dan hasil query dapat dikatakan berhasil jika software berhasil mengenkripsi query dan hasil query yang ditransmisikan sehingga apabila terjadi penyadapan terhadap keduanya, penyadap tidak akan mengerti isi data tersebut. Kesimpulan dari penelitian ini yaitu software yang dibangun

Relative aggregation operator in database fuzzy querying

Directory of Open Access Journals (Sweden)

Luminita DUMITRIU

2005-12-01

Full Text Available Fuzzy selection criteria querying relational databases include vague terms; they usually refer linguistic values form the attribute linguistic domains, defined as fuzzy sets. Generally, when a vague query is processed, the definitions of vague terms must already exist in a knowledge base. But there are also cases when vague terms must be dynamically defined, when a particular operation is used to aggregate simple criteria in a complex selection. The paper presents a new aggregation operator and the corresponding algorithm to evaluate the fuzzy query.

Query-Time Optimization Techniques for Structured Queries in Information Retrieval

Science.gov (United States)

Cartright, Marc-Allen

2013-01-01

The use of information retrieval (IR) systems is evolving towards larger, more complicated queries. Both the IR industrial and research communities have generated significant evidence indicating that in order to continue improving retrieval effectiveness, increases in retrieval model complexity may be unavoidable. From an operational perspective,…

Improving Web Search for Difficult Queries

Science.gov (United States)

Wang, Xuanhui

2009-01-01

Search engines have now become essential tools in all aspects of our life. Although a variety of information needs can be served very successfully, there are still a lot of queries that search engines can not answer very effectively and these queries always make users feel frustrated. Since it is quite often that users encounter such "difficult…

Processing SPARQL queries with regular expressions in RDF databases

Science.gov (United States)

2011-01-01

Background As the Resource Description Framework (RDF) data model is widely used for modeling and sharing a lot of online bioinformatics resources such as Uniprot (dev.isb-sib.ch/projects/uniprot-rdf) or Bio2RDF (bio2rdf.org), SPARQL - a W3C recommendation query for RDF databases - has become an important query language for querying the bioinformatics knowledge bases. Moreover, due to the diversity of users’ requests for extracting information from the RDF data as well as the lack of users’ knowledge about the exact value of each fact in the RDF databases, it is desirable to use the SPARQL query with regular expression patterns for querying the RDF data. To the best of our knowledge, there is currently no work that efficiently supports regular expression processing in SPARQL over RDF databases. Most of the existing techniques for processing regular expressions are designed for querying a text corpus, or only for supporting the matching over the paths in an RDF graph. Results In this paper, we propose a novel framework for supporting regular expression processing in SPARQL query. Our contributions can be summarized as follows. 1) We propose an efficient framework for processing SPARQL queries with regular expression patterns in RDF databases. 2) We propose a cost model in order to adapt the proposed framework in the existing query optimizers. 3) We build a prototype for the proposed framework in C++ and conduct extensive experiments demonstrating the efficiency and effectiveness of our technique. Conclusions Experiments with a full-blown RDF engine show that our framework outperforms the existing ones by up to two orders of magnitude in processing SPARQL queries with regular expression patterns. PMID:21489225

Processing SPARQL queries with regular expressions in RDF databases.

Science.gov (United States)

Lee, Jinsoo; Pham, Minh-Duc; Lee, Jihwan; Han, Wook-Shin; Cho, Hune; Yu, Hwanjo; Lee, Jeong-Hoon

2011-03-29

As the Resource Description Framework (RDF) data model is widely used for modeling and sharing a lot of online bioinformatics resources such as Uniprot (dev.isb-sib.ch/projects/uniprot-rdf) or Bio2RDF (bio2rdf.org), SPARQL - a W3C recommendation query for RDF databases - has become an important query language for querying the bioinformatics knowledge bases. Moreover, due to the diversity of users' requests for extracting information from the RDF data as well as the lack of users' knowledge about the exact value of each fact in the RDF databases, it is desirable to use the SPARQL query with regular expression patterns for querying the RDF data. To the best of our knowledge, there is currently no work that efficiently supports regular expression processing in SPARQL over RDF databases. Most of the existing techniques for processing regular expressions are designed for querying a text corpus, or only for supporting the matching over the paths in an RDF graph. In this paper, we propose a novel framework for supporting regular expression processing in SPARQL query. Our contributions can be summarized as follows. 1) We propose an efficient framework for processing SPARQL queries with regular expression patterns in RDF databases. 2) We propose a cost model in order to adapt the proposed framework in the existing query optimizers. 3) We build a prototype for the proposed framework in C++ and conduct extensive experiments demonstrating the efficiency and effectiveness of our technique. Experiments with a full-blown RDF engine show that our framework outperforms the existing ones by up to two orders of magnitude in processing SPARQL queries with regular expression patterns.

Efficient Thermal Tuning Employing Metallic Microheater With Slow Light Effect

DEFF Research Database (Denmark)

Yan, Siqi; Chen, Hao; Gao, Shengqian

2018-01-01

Thermal tuning acts as one of the most fundamental roles in integrated silicon photonics since it can provide flexibility and reconfigurability. Low tuning power and fast tuning speed are long-term pursuing goals in terms of the performance of the thermal tuning. Here we propose and experimentall...

Determinacy in Static Analysis of jQuery

DEFF Research Database (Denmark)

Andreasen, Esben; Møller, Anders

2014-01-01

Static analysis for JavaScript can potentially help programmers find errors early during development. Although much progress has been made on analysis techniques, a major obstacle is the prevalence of libraries, in particular jQuery, which apply programming patterns that have detrimental conseque......Static analysis for JavaScript can potentially help programmers find errors early during development. Although much progress has been made on analysis techniques, a major obstacle is the prevalence of libraries, in particular jQuery, which apply programming patterns that have detrimental...... present a static dataflow analysis for JavaScript that infers and exploits determinacy information on-the-fly, to enable analysis of some of the most complex parts of jQuery. The techniques are implemented in the TAJS analysis tool and evaluated on a collection of small programs that use jQuery. Our...

Practical quantum private query with better performance in resisting joint-measurement attack

Science.gov (United States)

Wei, Chun-Yan; Wang, Tian-Yin; Gao, Fei

2016-04-01

As a kind of practical protocol, quantum-key-distribution (QKD)-based quantum private queries (QPQs) have drawn lots of attention. However, joint-measurement (JM) attack poses a noticeable threat to the database security in such protocols. That is, by JM attack a malicious user can illegally elicit many more items from the database than the average amount an honest one can obtain. Taking Jacobi et al.'s protocol as an example, by JM attack a malicious user can obtain as many as 500 bits, instead of the expected 2.44 bits, from a 104-bit database in one query. It is a noticeable security flaw in theory, and would also arise in application with the development of quantum memories. To solve this problem, we propose a QPQ protocol based on a two-way QKD scheme, which behaves much better in resisting JM attack. Concretely, the user Alice cannot get more database items by conducting JM attack on the qubits because she has to send them back to Bob (the database holder) before knowing which of them should be jointly measured. Furthermore, JM attack by both Alice and Bob would be detected with certain probability, which is quite different from previous protocols. Moreover, our protocol retains the good characters of QKD-based QPQs, e.g., it is loss tolerant and robust against quantum memory attack.

Overtaking CPU DBMSes with a GPU in whole-query analytic processing with parallelism-friendly execution plan optimization

NARCIS (Netherlands)

A. Agbaria (Adnan); D. Minor (David); N. Peterfreund (Natan); E. Rozenberg (Eyal); O. Rosenberg (Ofer); Huawei Research

2016-01-01

textabstractExisting work on accelerating analytic DB query processing with (discrete) GPUs fails to fully realize their potential for speedup through parallelism: Published results do not achieve significant speedup over more performant CPU-only DBMSes when processing complete queries. This

Experimental quantum private queries with linear optics

International Nuclear Information System (INIS)

De Martini, Francesco; Giovannetti, Vittorio; Lloyd, Seth; Maccone, Lorenzo; Nagali, Eleonora; Sansoni, Linda; Sciarrino, Fabio

2009-01-01

The quantum private query is a quantum cryptographic protocol to recover information from a database, preserving both user and data privacy: the user can test whether someone has retained information on which query was asked and the database provider can test the amount of information released. Here we discuss a variant of the quantum private query algorithm that admits a simple linear optical implementation: it employs the photon's momentum (or time slot) as address qubits and its polarization as bus qubit. A proof-of-principle experimental realization is implemented.

Achieve Location Privacy-Preserving Range Query in Vehicular Sensing.

Science.gov (United States)

Kong, Qinglei; Lu, Rongxing; Ma, Maode; Bao, Haiyong

2017-08-08

Modern vehicles are equipped with a plethora of on-board sensors and large on-board storage, which enables them to gather and store various local-relevant data. However, the wide application of vehicular sensing has its own challenges, among which location-privacy preservation and data query accuracy are two critical problems. In this paper, we propose a novel range query scheme, which helps the data requester to accurately retrieve the sensed data from the distributive on-board storage in vehicular ad hoc networks (VANETs) with location privacy preservation. The proposed scheme exploits structured scalars to denote the locations of data requesters and vehicles, and achieves the privacy-preserving location matching with the homomorphic Paillier cryptosystem technique. Detailed security analysis shows that the proposed range query scheme can successfully preserve the location privacy of the involved data requesters and vehicles, and protect the confidentiality of the sensed data. In addition, performance evaluations are conducted to show the efficiency of the proposed scheme, in terms of computation delay and communication overhead. Specifically, the computation delay and communication overhead are not dependent on the length of the scalar, and they are only proportional to the number of vehicles.

Investigation of multiple visualisation techniques and dynamic queries in conjunction with direct sonification to support the browsing of audio resources

OpenAIRE

Brazil, Eoin

2003-01-01

non-peer-reviewed In this thesis, a prototype system for the browsing of audio resources was developed and an initial evaluation of this system was performed. The main contributions of this thesis are dynamic queries and multiple visualisation techniques in conjunction with direct sonification. Dynamic queries are queries that provide immediate feedback while maintaining consistency between the queries themselves and the graphical/auditory display. The multiple visualisation techniques are...

Parallelizing Federated SPARQL Queries in Presence of Replicated Data

DEFF Research Database (Denmark)

Minier, Thomas; Montoya, Gabriela; Skaf-Molli, Hala

2017-01-01

Federated query engines have been enhanced to exploit new data localities created by replicated data, e.g., Fedra. However, existing replication aware federated query engines mainly focus on pruning sources during the source selection and query decomposition in order to reduce intermediate result...

Modeling Large Time Series for Efficient Approximate Query Processing

DEFF Research Database (Denmark)

Perera, Kasun S; Hahmann, Martin; Lehner, Wolfgang

2015-01-01

query statistics derived from experiments and when running the system. Our approach can also reduce communication load by exchanging models instead of data. To allow seamless integration of model-based querying into traditional data warehouses, we introduce a SQL compatible query terminology. Our...

Approximating terminological queries

NARCIS (Netherlands)

Stuckenschmidt, Heiner; Van Harmelen, Frank

2002-01-01

Current proposals for languages to encode terminological knowledge in intelligent systems support logical reasoning for answering user queries about objects and classes. An application of these languages on the World Wide Web, however, is hampered by the limitations of logical reasoning in terms

A study of medical and health queries to web search engines.

Science.gov (United States)

Spink, Amanda; Yang, Yin; Jansen, Jim; Nykanen, Pirrko; Lorence, Daniel P; Ozmutlu, Seda; Ozmutlu, H Cenk

2004-03-01

This paper reports findings from an analysis of medical or health queries to different web search engines. We report results: (i). comparing samples of 10000 web queries taken randomly from 1.2 million query logs from the AlltheWeb.com and Excite.com commercial web search engines in 2001 for medical or health queries, (ii). comparing the 2001 findings from Excite and AlltheWeb.com users with results from a previous analysis of medical and health related queries from the Excite Web search engine for 1997 and 1999, and (iii). medical or health advice-seeking queries beginning with the word 'should'. Findings suggest: (i). a small percentage of web queries are medical or health related, (ii). the top five categories of medical or health queries were: general health, weight issues, reproductive health and puberty, pregnancy/obstetrics, and human relationships, and (iii). over time, the medical and health queries may have declined as a proportion of all web queries, as the use of specialized medical/health websites and e-commerce-related queries has increased. Findings provide insights into medical and health-related web querying and suggests some implications for the use of the general web search engines when seeking medical/health information.

Processing SPARQL queries with regular expressions in RDF databases

Directory of Open Access Journals (Sweden)

Cho Hune

2011-03-01

Full Text Available Abstract Background As the Resource Description Framework (RDF data model is widely used for modeling and sharing a lot of online bioinformatics resources such as Uniprot (dev.isb-sib.ch/projects/uniprot-rdf or Bio2RDF (bio2rdf.org, SPARQL - a W3C recommendation query for RDF databases - has become an important query language for querying the bioinformatics knowledge bases. Moreover, due to the diversity of users’ requests for extracting information from the RDF data as well as the lack of users’ knowledge about the exact value of each fact in the RDF databases, it is desirable to use the SPARQL query with regular expression patterns for querying the RDF data. To the best of our knowledge, there is currently no work that efficiently supports regular expression processing in SPARQL over RDF databases. Most of the existing techniques for processing regular expressions are designed for querying a text corpus, or only for supporting the matching over the paths in an RDF graph. Results In this paper, we propose a novel framework for supporting regular expression processing in SPARQL query. Our contributions can be summarized as follows. 1 We propose an efficient framework for processing SPARQL queries with regular expression patterns in RDF databases. 2 We propose a cost model in order to adapt the proposed framework in the existing query optimizers. 3 We build a prototype for the proposed framework in C++ and conduct extensive experiments demonstrating the efficiency and effectiveness of our technique. Conclusions Experiments with a full-blown RDF engine show that our framework outperforms the existing ones by up to two orders of magnitude in processing SPARQL queries with regular expression patterns.

A Query Evaluation Approach using Opinions of Turkish Financial Market Professionals

Directory of Open Access Journals (Sweden)

Bora Uğurlu

2015-08-01

Full Text Available People who do not have expertise in the financial area may not see the relationship between the numerical and linguistic data. In our study, a knowledge discovery approach using Turkish natural language processing is recommended in order to respond to meaningful queries and classify them with high accuracy. Query corpus consists of randomly selected unique keywords. Quantitative evaluation is done in order to measure the classification performance. Experimental results indicate that our proposed approach is sufficiently consistent with and able to make categorical classifications correctly. The approach highlights the relationship between numerical and linguistic data obtained from Turkish financial market.

RDF-GL : a SPARQL-based graphical query language for RDF

NARCIS (Netherlands)

Hogenboom, F.P.; Milea, D.V.; Frasincar, F.; Kaymak, U.; Chbeir, R.; Badr, Y.; Abraham, A.; Hassanien, A.-E.

2010-01-01

This chapter presents RDF-GL, a graphical query language (GQL) for RDF. The GQL is based on the textual query language SPARQL and mainly focuses on SPARQL SELECT queries. The advantage of a GQL over textual query languages is that complexity is hidden through the use of graphical symbols. RDF-GL is

Accelerating SPARQL queries by exploiting hash-based locality and adaptive partitioning

KAUST Repository

Al-Harbi, Razen; Abdelaziz, Ibrahim; Kalnis, Panos; Mamoulis, Nikos; Ebrahim, Yasser; Sahli, Majed

2016-01-01

State-of-the-art distributed RDF systems partition data across multiple computer nodes (workers). Some systems perform cheap hash partitioning, which may result in expensive query evaluation. Others try to minimize inter-node communication, which

Executing SPARQL Queries over the Web of Linked Data

Science.gov (United States)

Hartig, Olaf; Bizer, Christian; Freytag, Johann-Christoph

The Web of Linked Data forms a single, globally distributed dataspace. Due to the openness of this dataspace, it is not possible to know in advance all data sources that might be relevant for query answering. This openness poses a new challenge that is not addressed by traditional research on federated query processing. In this paper we present an approach to execute SPARQL queries over the Web of Linked Data. The main idea of our approach is to discover data that might be relevant for answering a query during the query execution itself. This discovery is driven by following RDF links between data sources based on URIs in the query and in partial results. The URIs are resolved over the HTTP protocol into RDF data which is continuously added to the queried dataset. This paper describes concepts and algorithms to implement our approach using an iterator-based pipeline. We introduce a formalization of the pipelining approach and show that classical iterators may cause blocking due to the latency of HTTP requests. To avoid blocking, we propose an extension of the iterator paradigm. The evaluation of our approach shows its strengths as well as the still existing challenges.

A Fuzzy Query Mechanism for Human Resource Websites

Science.gov (United States)

Lai, Lien-Fu; Wu, Chao-Chin; Huang, Liang-Tsung; Kuo, Jung-Chih

Users' preferences often contain imprecision and uncertainty that are difficult for traditional human resource websites to deal with. In this paper, we apply the fuzzy logic theory to develop a fuzzy query mechanism for human resource websites. First, a storing mechanism is proposed to store fuzzy data into conventional database management systems without modifying DBMS models. Second, a fuzzy query language is proposed for users to make fuzzy queries on fuzzy databases. User's fuzzy requirement can be expressed by a fuzzy query which consists of a set of fuzzy conditions. Third, each fuzzy condition associates with a fuzzy importance to differentiate between fuzzy conditions according to their degrees of importance. Fourth, the fuzzy weighted average is utilized to aggregate all fuzzy conditions based on their degrees of importance and degrees of matching. Through the mutual compensation of all fuzzy conditions, the ordering of query results can be obtained according to user's preference.

Evaluating Trajectory Queries over Imprecise Location Data

DEFF Research Database (Denmark)

Xie, Scott, Xike; Cheng, Reynold; Yiu, Man Lung

2012-01-01

Trajectory queries, which retrieve nearby objects for every point of a given route, can be used to identify alerts of potential threats along a vessel route, or monitor the adjacent rescuers to a travel path. However, the locations of these objects (e.g., threats, succours) may not be precisely...... obtained due to hardware limitations of measuring devices, as well as the constantly-changing nature of the external environment. Ignoring data uncertainty can render low query quality, and cause undesirable consequences such as missing alerts of threats and poor response time in rescue operations. Also......, the query is quite time-consuming, since all the points on the trajectory are considered. In this paper, we study how to efficiently evaluate trajectory queries over imprecise location data, by proposing a new concept called the u-bisector. In general, the u-bisector is an extension of bisector to handle...

Semantic querying of data guided by Formal Concept Analysis

OpenAIRE

Codocedo , Victor; Lykourentzou , Ioanna; Napoli , Amedeo

2012-01-01

International audience; In this paper we present a novel approach to handle querying over a concept lattice of documents and annotations. We focus on the problem of "non-matching documents", which are those that, despite being semantically relevant to the user query, do not contain the query's elements and hence cannot be retrieved by typical string matching approaches. In order to find these documents, we modify the initial user query using the concept lattice as a guide. We achieve this by ...

Unemployment Insurance Query (UIQ)

Data.gov (United States)

Social Security Administration — The Unemployment Insurance Query (UIQ) provides State Unemployment Insurance agencies real-time online access to SSA data. This includes SSN verification and Title...

Improving Convergence of Iterative Feedback Tuning using Optimal External Perturbations

DEFF Research Database (Denmark)

Huusom, Jakob Kjøbsted; Hjalmarsson, Håkon; Poulsen, Niels Kjølstad

2008-01-01

Iterative feedback tuning constitutes an attractive control loop tuning method for processes in the absence of sufficient process insight. It is a purely data driven approach to optimization of the loop performance. The standard formulation ensures an unbiased estimate of the loop performance cost...... function gradient, which is used in a search algorithm. A slow rate of convergence of the tuning method is often experienced when tuning for disturbance rejection. This is due to a poor signal to noise ratio in the process data. A method is proposed for increasing the information content in data...

Evaluation of Controller Tuning Methods Applied to Distillation Column Control

DEFF Research Database (Denmark)

Nielsen, Kim; W. Andersen, Henrik; Kümmel, Professor Mogens

A frequency domain approach is used to compare the nominal performance and robustness of dual composition distillation column control tuned according to Ziegler-Nichols (ZN) and Biggest Log Modulus Tuning (BLT) for three binary distillation columns, WOBE, LUVI and TOFA. The scope of this is to ex......A frequency domain approach is used to compare the nominal performance and robustness of dual composition distillation column control tuned according to Ziegler-Nichols (ZN) and Biggest Log Modulus Tuning (BLT) for three binary distillation columns, WOBE, LUVI and TOFA. The scope...

A Relational Algebra Query Language for Programming Relational Databases

Science.gov (United States)

McMaster, Kirby; Sambasivam, Samuel; Anderson, Nicole

2011-01-01

In this paper, we describe a Relational Algebra Query Language (RAQL) and Relational Algebra Query (RAQ) software product we have developed that allows database instructors to teach relational algebra through programming. Instead of defining query operations using mathematical notation (the approach commonly taken in database textbooks), students…

Efficient Partitioning of Large Databases without Query Statistics

Directory of Open Access Journals (Sweden)

Shahidul Islam KHAN

2016-11-01

Full Text Available An efficient way of improving the performance of a database management system is distributed processing. Distribution of data involves fragmentation or partitioning, replication, and allocation process. Previous research works provided partitioning based on empirical data about the type and frequency of the queries. These solutions are not suitable at the initial stage of a distributed database as query statistics are not available then. In this paper, I have presented a fragmentation technique, Matrix based Fragmentation (MMF, which can be applied at the initial stage as well as at later stages of distributed databases. Instead of using empirical data, I have developed a matrix, Modified Create, Read, Update and Delete (MCRUD, to partition a large database properly. Allocation of fragments is done simultaneously in my proposed technique. So using MMF, no additional complexity is added for allocating the fragments to the sites of a distributed database as fragmentation is synchronized with allocation. The performance of a DDBMS can be improved significantly by avoiding frequent remote access and high data transfer among the sites. Results show that proposed technique can solve the initial partitioning problem of large distributed databases.

An Efficient and Privacy-Preserving Multiuser Cloud-Based LBS Query Scheme

Directory of Open Access Journals (Sweden)

Lu Ou

2018-01-01

Full Text Available Location-based services (LBSs are increasingly popular in today’s society. People reveal their location information to LBS providers to obtain personalized services such as map directions, restaurant recommendations, and taxi reservations. Usually, LBS providers offer user privacy protection statement to assure users that their private location information would not be given away. However, many LBSs run on third-party cloud infrastructures. It is challenging to guarantee user location privacy against curious cloud operators while still permitting users to query their own location information data. In this paper, we propose an efficient privacy-preserving cloud-based LBS query scheme for the multiuser setting. We encrypt LBS data and LBS queries with a hybrid encryption mechanism, which can efficiently implement privacy-preserving search over encrypted LBS data and is very suitable for the multiuser setting with secure and effective user enrollment and user revocation. This paper contains security analysis and performance experiments to demonstrate the privacy-preserving properties and efficiency of our proposed scheme.

Instant MDX queries for SQL Server 2012

CERN Document Server

Emond, Nicholas

2013-01-01

Get to grips with a new technology, understand what it is and what it can do for you, and then get to work with the most important features and tasks. This short, focused guide is a great way to get stated with writing MDX queries. New developers can use this book as a reference for how to use functions and the syntax of a query as well as how to use Calculated Members and Named Sets.This book is great for new developers who want to learn the MDX query language from scratch and install SQL Server 2012 with Analysis Services

Keyword Query Expansion Paradigm Based on Recommendation and Interpretation in Relational Databases

Directory of Open Access Journals (Sweden)

Yingqi Wang

2017-01-01

Full Text Available Due to the ambiguity and impreciseness of keyword query in relational databases, the research on keyword query expansion has attracted wide attention. Existing query expansion methods expose users’ query intention to a certain extent, but most of them cannot balance the precision and recall. To address this problem, a novel two-step query expansion approach is proposed based on query recommendation and query interpretation. First, a probabilistic recommendation algorithm is put forward by constructing a term similarity matrix and Viterbi model. Second, by using the translation algorithm of triples and construction algorithm of query subgraphs, query keywords are translated to query subgraphs with structural and semantic information. Finally, experimental results on a real-world dataset demonstrate the effectiveness and rationality of the proposed method.

Enabling Semantic Queries Against the Spatial Database

Directory of Open Access Journals (Sweden)

PENG, X.

2012-02-01

Full Text Available The spatial database based upon the object-relational database management system (ORDBMS has the merits of a clear data model, good operability and high query efficiency. That is why it has been widely used in spatial data organization and management. However, it cannot express the semantic relationships among geospatial objects, making the query results difficult to meet the user's requirement well. Therefore, this paper represents an attempt to combine the Semantic Web technology with the spatial database so as to make up for the traditional database's disadvantages. In this way, on the one hand, users can take advantages of ORDBMS to store and manage spatial data; on the other hand, if the spatial database is released in the form of Semantic Web, the users could describe a query more concisely with the cognitive pattern which is similar to that of daily life. As a consequence, this methodology enables the benefits of both Semantic Web and the object-relational database (ORDB available. The paper discusses systematically the semantic enriched spatial database's architecture, key technologies and implementation. Subsequently, we demonstrate the function of spatial semantic queries via a practical prototype system. The query results indicate that the method used in this study is feasible.

Extracting Rankings for Spatial Keyword Queries from GPS Data

DEFF Research Database (Denmark)

Keles, Ilkcan; Jensen, Christian Søndergaard; Saltenis, Simonas

2018-01-01

Studies suggest that many search engine queries have local intent. We consider the evaluation of ranking functions important for such queries. The key challenge is to be able to determine the “best” ranking for a query, as this enables evaluation of the results of ranking functions. We propose...

An Object-Oriented Approach of Keyword Querying over Fuzzy XML

Directory of Open Access Journals (Sweden)

Ting Li

2016-09-01

Full Text Available As the fuzzy data management has become one of the main research topics and directions, the question of how to obtain the useful information by means of keyword query from fuzzy XML documents is becoming a subject of an increasing needed investigation. Considering the keyword query methods on crisp XML documents, smallest lowest common ancestor (SLCA semantics is one of the most widely accepted semantics. When users propose the keyword query on fuzzy XML documents with the SLCA semantics, the query results are always incomplate, with low precision, and with no possibilities values returned. Most of keyword query semantics on XML documents only consider query results matching all keywords, yet users may also be interested in the query results matching partial keywords. To overcome these limitations, in this paper, we investigate how to obtain more comprehensive and meaningful results of keyword querying on fuzzy XML documents. We propose a semantics of object-oriented keyword querying on fuzzy XML documents. First, we introduce the concept of "object tree", analyze different types of matching result object trees and find the "minimum result object trees" which contain all keywords and "result object trees" which contain partial keywords. Then an object-oriented keyword query algorithm ROstack is proposed to obtain the root nodes of these matching result object trees, together with their possibilities. At last, experiments are conducted to verify the effectiveness and efficiency of our proposed algorithm.

Processing of extreme moving-object update and query workloads in main memory

DEFF Research Database (Denmark)

Sidlauskas, Darius; Saltenis, Simonas; Jensen, Christian S.

2014-01-01

traditional transaction processing in the context of our target domain and propose new semantics that enable a high degree of parallelism and ensure up-to-date query results. We define the new semantics for range and k-nearest neighbor queries. Then, we present a main-memory indexing technique called parallel...... grid that implements the proposed semantics as well as two other variants supporting different semantics. This enables us to quantify the effects that different degrees of consistency have on performance. We also present an alternative time-partitioning approach. Empirical studies with the above...

Age-related differences in the accuracy of web query-based predictions of influenza-like illness.

Directory of Open Access Journals (Sweden)

Alexander Domnich

Full Text Available Web queries are now widely used for modeling, nowcasting and forecasting influenza-like illness (ILI. However, given that ILI attack rates vary significantly across ages, in terms of both magnitude and timing, little is known about whether the association between ILI morbidity and ILI-related queries is comparable across different age-groups. The present study aimed to investigate features of the association between ILI morbidity and ILI-related query volume from the perspective of age.Since Google Flu Trends is unavailable in Italy, Google Trends was used to identify entry terms that correlated highly with official ILI surveillance data. All-age and age-class-specific modeling was performed by means of linear models with generalized least-square estimation. Hold-out validation was used to quantify prediction accuracy. For purposes of comparison, predictions generated by exponential smoothing were computed.Five search terms showed high correlation coefficients of > .6. In comparison with exponential smoothing, the all-age query-based model correctly predicted the peak time and yielded a higher correlation coefficient with observed ILI morbidity (.978 vs. .929. However, query-based prediction of ILI morbidity was associated with a greater error. Age-class-specific query-based models varied significantly in terms of prediction accuracy. In the 0-4 and 25-44-year age-groups, these did well and outperformed exponential smoothing predictions; in the 15-24 and ≥ 65-year age-classes, however, the query-based models were inaccurate and highly overestimated peak height. In all but one age-class, peak timing predicted by the query-based models coincided with observed timing.The accuracy of web query-based models in predicting ILI morbidity rates could differ among ages. Greater age-specific detail may be useful in flu query-based studies in order to account for age-specific features of the epidemiology of ILI.

Genetic algorithms for RDF chain query optimization

NARCIS (Netherlands)

Hogenboom, A.C.; Milea, D.V.; Frasincar, F.; Kaymak, U.; Calders, T.; Tuyls, K.; Pechenizkiy, M.

2009-01-01

The application of Semantic Web technologies in an Electronic Commerce environment implies a need for good support tools. Fast query engines are required for efficient real-time querying of large amounts of data, usually represented using RDF. We focus on optimizing a special class of SPARQL

Accurate guitar tuning by cochlear implant musicians.

Directory of Open Access Journals (Sweden)

Thomas Lu

Full Text Available Modern cochlear implant (CI users understand speech but find difficulty in music appreciation due to poor pitch perception. Still, some deaf musicians continue to perform with their CI. Here we show unexpected results that CI musicians can reliably tune a guitar by CI alone and, under controlled conditions, match simultaneously presented tones to <0.5 Hz. One subject had normal contralateral hearing and produced more accurate tuning with CI than his normal ear. To understand these counterintuitive findings, we presented tones sequentially and found that tuning error was larger at ∼ 30 Hz for both subjects. A third subject, a non-musician CI user with normal contralateral hearing, showed similar trends in performance between CI and normal hearing ears but with less precision. This difference, along with electric analysis, showed that accurate tuning was achieved by listening to beats rather than discriminating pitch, effectively turning a spectral task into a temporal discrimination task.

Case-based Reasoning for Automotive Engine Performance Tune-up

International Nuclear Information System (INIS)

Vong, C. M.; Huang, H.; Wong, P. K.

2010-01-01

The automotive engine performance tune-up is greatly affected by the calibration of its electronic control unit (ECU). The ECU calibration is traditionally done by trial-and-error method. This traditional method consumes a large amount of time and money because of a large number of dynamometer tests. To resolve this problem, case based reasoning (CBR) is employed, so that an existing and effective ECU setup can be adapted to fit another similar class of engines. The adaptation procedure is done through a more sophisticated step called case-based adaptation (CBA)[1, 2]. CBA is an effective knowledge management tool, which can interactively learn the expert adaptation knowledge. The paper briefly reviews the methodologies of CBR and CBA. Then the application to ECU calibration is described via a case study. With CBR and CBA, the efficiency of calibrating an ECU can be enhanced. A prototype system has also been developed to verify the usefulness of CBR in ECU calibration.

Error Checking for Chinese Query by Mining Web Log

Directory of Open Access Journals (Sweden)

Jianyong Duan

2015-01-01

Full Text Available For the search engine, error-input query is a common phenomenon. This paper uses web log as the training set for the query error checking. Through the n-gram language model that is trained by web log, the queries are analyzed and checked. Some features including query words and their number are introduced into the model. At the same time data smoothing algorithm is used to solve data sparseness problem. It will improve the overall accuracy of the n-gram model. The experimental results show that it is effective.

Application of Clustering Algorithm CLOPE to the Query Grouping Problem in the Field of Materialized View Maintenance

Directory of Open Access Journals (Sweden)

Kateryna Novokhatska

2016-03-01

Full Text Available In recent years, materialized views (MVs are widely used to enhance the database performance by storing pre-calculated results of resource-intensive queries in the physical memory. In order to identify which queries may be potentially materialized, database transaction log for a long period of time should be analyzed. The goal of analysis is to distinguish resource-intensive and frequently used queries collected from database log, and optimize these queries by implementation of MVs. In order to achieve greater efficiency of MVs, they were used not only for the optimization of single queries, but also for entire groups of queries that are similar in syntax and execution results. Thus, the problem stated in this article is the development of approach that will allow forming groups of queries with similar syntax around the most resource-intensive queries in order to identify the list of potential candidates for materialization. For solving this problem, we have applied the algorithm of categorical data clustering to the query grouping problem on the step of database log analysis and searching candidates for materialization. In the current work CLOPE algorithm was modified to cover the introduced problem. Statistical and timing indicators were taken into account in order to form the clusters around the most resource intensive queries. Application of modified algorithm CLOPE allowed to decrease calculable complexity of clustering and to enhance the quality of formed groups.

Efficient evaluation of shortest travel-time path queries through spatial mashups

KAUST Repository

Zhang, Detian

2017-01-07

In the real world, the route/path with the shortest travel time in a road network is more meaningful than that with the shortest network distance for location-based services (LBS). However, not every LBS provider has adequate resources to compute/estimate travel time for routes by themselves. A cost-effective way for LBS providers to estimate travel time for routes is to issue external route requests to Web mapping services (e.g., Google Maps, Bing Maps, and MapQuest Maps). Due to the high cost of processing such external route requests and the usage limits of Web mapping services, we take the advantage of direction sharing, parallel requesting and waypoints supported by Web mapping services to reduce the number of external route requests and the query response time for shortest travel-time route queries in this paper. We first give the definition of sharing ability to reflect the possibility of sharing the direction information of a route with others, and find out the queries that their query routes are independent with each other for parallel processing. Then, we model the problem of selecting the optimal waypoints for an external route request as finding the longest simple path in a weighted complete digraph. As it is a MAX SNP-hard problem, we propose a greedy algorithm with performance guarantee to find the best set of waypoints in an external route request. We evaluate the performance of our approach using a real Web mapping service, a real road network, real and synthetic data sets. Experimental results show the efficiency, scalability, and applicability of our approach.

Efficient evaluation of shortest travel-time path queries through spatial mashups

KAUST Repository

Zhang, Detian; Chow, Chi-Yin; Liu, An; Zhang, Xiangliang; Ding, Qingzhu; Li, Qing

2017-01-01

In the real world, the route/path with the shortest travel time in a road network is more meaningful than that with the shortest network distance for location-based services (LBS). However, not every LBS provider has adequate resources to compute/estimate travel time for routes by themselves. A cost-effective way for LBS providers to estimate travel time for routes is to issue external route requests to Web mapping services (e.g., Google Maps, Bing Maps, and MapQuest Maps). Due to the high cost of processing such external route requests and the usage limits of Web mapping services, we take the advantage of direction sharing, parallel requesting and waypoints supported by Web mapping services to reduce the number of external route requests and the query response time for shortest travel-time route queries in this paper. We first give the definition of sharing ability to reflect the possibility of sharing the direction information of a route with others, and find out the queries that their query routes are independent with each other for parallel processing. Then, we model the problem of selecting the optimal waypoints for an external route request as finding the longest simple path in a weighted complete digraph. As it is a MAX SNP-hard problem, we propose a greedy algorithm with performance guarantee to find the best set of waypoints in an external route request. We evaluate the performance of our approach using a real Web mapping service, a real road network, real and synthetic data sets. Experimental results show the efficiency, scalability, and applicability of our approach.

A semantic perspective on query log analysis

NARCIS (Netherlands)

Hofmann, K.; de Rijke, M.; Huurnink, B.; Meij, E.

2009-01-01

We present our views on the CLEF log file analysis task. We argue for a task definition that focuses on the semantic enrichment of query logs. In addition, we discuss how additional information about the context in which queries are being made could further our understanding of users’ information

Optimizing RDF Data Cubes for Efficient Processing of Analytical Queries

DEFF Research Database (Denmark)

Jakobsen, Kim Ahlstrøm; Andersen, Alex B.; Hose, Katja

2015-01-01

data warehouses and data cubes. Today, external data sources are essential for analytics and, as the Semantic Web gains popularity, more and more external sources are available in native RDF. With the recent SPARQL 1.1 standard, performing analytical queries over RDF data sources has finally become...

Query optimization for graph analytics on linked data using SPARQL

Energy Technology Data Exchange (ETDEWEB)

Hong, Seokyong [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Lee, Sangkeun [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Lim, Seung -Hwan [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Sukumar, Sreenivas R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Vatsavai, Ranga Raju [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2015-07-01

Triplestores that support query languages such as SPARQL are emerging as the preferred and scalable solution to represent data and meta-data as massive heterogeneous graphs using Semantic Web standards. With increasing adoption, the desire to conduct graph-theoretic mining and exploratory analysis has also increased. Addressing that desire, this paper presents a solution that is the marriage of Graph Theory and the Semantic Web. We present software that can analyze Linked Data using graph operations such as counting triangles, finding eccentricity, testing connectedness, and computing PageRank directly on triple stores via the SPARQL interface. We describe the process of optimizing performance of the SPARQL-based implementation of such popular graph algorithms by reducing the space-overhead, simplifying iterative complexity and removing redundant computations by understanding query plans. Our optimized approach shows significant performance gains on triplestores hosted on stand-alone workstations as well as hardware-optimized scalable supercomputers such as the Cray XMT.

Adaptive and Optimized RDF Query Interface for Distributed WFS Data

Directory of Open Access Journals (Sweden)

Tian Zhao

2017-04-01

Full Text Available Web Feature Service (WFS is a protocol for accessing geospatial data stores such as databases and Shapefiles over the Web. However, WFS does not provide direct access to data distributed in multiple servers. In addition, WFS features extracted from their original sources are not convenient for user access due to the lack of connection to high-level concepts. Users are facing the choices of either querying each WFS server first and then integrating the results, or converting the data from all WFS servers to a more expressive format such as RDF (Resource Description Framework and then querying the integrated data. The first choice requires additional programming while the second choice is not practical for large or frequently updated datasets. The new contribution of this paper is that we propose a novel adaptive and optimized RDF query interface to overcome the aforementioned limitation. Specifically, in this paper, we propose a novel algorithm to query and synthesize distributed WFS data through an RDF query interface, where users can specify data requests to multiple WFS servers using a single RDF query. Users can also define a simple configuration to associate WFS feature types, attributes, and values with RDF classes, properties, and values so that user queries can be written using a more uniform and informative vocabulary. The algorithm translates each RDF query written in SPARQL-like syntax to multiple WFS GetFeature requests, and then converts and integrates the multiple WFS results to get the answers to the original query. The generated GetFeature requests are sent asynchronously and simultaneously to WFS servers to take advantage of the server parallelism. The results of each GetFeature request are cached to improve query response time for subsequent queries that involve one or more of the cached requests. A JavaScript-based prototype is implemented and experimental results show that the query response time can be greatly reduced through

Federated query processing for the semantic web

CERN Document Server

Buil-Aranda, C

2014-01-01

During the last years, the amount of RDF data has increased exponentially over the Web, exposed via SPARQL endpoints. These SPARQL endpoints allow users to direct SPARQL queries to the RDF data. Federated SPARQL query processing allows to query several of these RDF databases as if they were a single one, integrating the results from all of them. This is a key concept in the Web of Data and it is also a hot topic in the community. Besides of that, the W3C SPARQL-WG has standardized it in the new Recommendation SPARQL 1.1.This book provides a formalisation of the W3C proposed recommendation. Thi

SM4MQ: A Semantic Model for Multidimensional Queries

DEFF Research Database (Denmark)

Varga, Jovan; Dobrokhotova, Ekaterina; Romero, Oscar

2017-01-01

On-Line Analytical Processing (OLAP) is a data analysis approach to support decision-making. On top of that, Exploratory OLAP is a novel initiative for the convergence of OLAP and the Semantic Web (SW) that enables the use of OLAP techniques on SW data. Moreover, OLAP approaches exploit different......, sharing, and reuse on the SW. As OLAP is based on the underlying multidimensional (MD) data model we denote such queries as MD queries and define SM4MQ: A Semantic Model for Multidimensional Queries. Furthermore, we propose a method to automate the exploitation of queries by means of SPARQL. We apply...

Accelerating SPARQL Queries and Analytics on RDF Data

KAUST Repository

Al-Harbi, Razen

2016-01-01

The complexity of SPARQL queries and RDF applications poses great challenges on distributed RDF management systems. SPARQL workloads are dynamic and con- sist of queries with variable complexities. Hence, systems that use static partitioning su

Query Language for Location-Based Services: A Model Checking Approach

Science.gov (United States)

Hoareau, Christian; Satoh, Ichiro

We present a model checking approach to the rationale, implementation, and applications of a query language for location-based services. Such query mechanisms are necessary so that users, objects, and/or services can effectively benefit from the location-awareness of their surrounding environment. The underlying data model is founded on a symbolic model of space organized in a tree structure. Once extended to a semantic model for modal logic, we regard location query processing as a model checking problem, and thus define location queries as hybrid logicbased formulas. Our approach is unique to existing research because it explores the connection between location models and query processing in ubiquitous computing systems, relies on a sound theoretical basis, and provides modal logic-based query mechanisms for expressive searches over a decentralized data structure. A prototype implementation is also presented and will be discussed.

Energy-aware SQL query acceleration through FPGA-based dynamic partial reconfiguration

NARCIS (Netherlands)

Becher, Andreas; Bauer, Florian; Ziener, Daniel; Teich, Jürgen

2014-01-01

In this paper, we propose an approach for energy-aware FPGA-based query acceleration for databases on embedded devices. After the analysis of an incoming query, a query-specific hardware accelerator is generated on-the-fly and loaded on the FPGA for subsequent query execution using partial dynamic

How Do Children Reformulate Their Search Queries?

Science.gov (United States)

Rutter, Sophie; Ford, Nigel; Clough, Paul

2015-01-01

Introduction: This paper investigates techniques used by children in year 4 (age eight to nine) of a UK primary school to reformulate their queries, and how they use information retrieval systems to support query reformulation. Method: An in-depth study analysing the interactions of twelve children carrying out search tasks in a primary school…

Selective enhancement of orientation tuning before saccades.

Science.gov (United States)

Ohl, Sven; Kuper, Clara; Rolfs, Martin

2017-11-01

Saccadic eye movements cause a rapid sweep of the visual image across the retina and bring the saccade's target into high-acuity foveal vision. Even before saccade onset, visual processing is selectively prioritized at the saccade target. To determine how this presaccadic attention shift exerts its influence on visual selection, we compare the dynamics of perceptual tuning curves before movement onset at the saccade target and in the opposite hemifield. Participants monitored a 30-Hz sequence of randomly oriented gratings for a target orientation. Combining a reverse correlation technique previously used to study orientation tuning in neurons and general additive mixed modeling, we found that perceptual reports were tuned to the target orientation. The gain of orientation tuning increased markedly within the last 100 ms before saccade onset. In addition, we observed finer orientation tuning right before saccade onset. This increase in gain and tuning occurred at the saccade target location and was not observed at the incongruent location in the opposite hemifield. The present findings suggest, therefore, that presaccadic attention exerts its influence on vision in a spatially and feature-selective manner, enhancing performance and sharpening feature tuning at the future gaze location before the eyes start moving.

ConnectomeExplorer: Query-guided visual analysis of large volumetric neuroscience data

KAUST Repository

Beyer, Johanna

2013-12-01

This paper presents ConnectomeExplorer, an application for the interactive exploration and query-guided visual analysis of large volumetric electron microscopy (EM) data sets in connectomics research. Our system incorporates a knowledge-based query algebra that supports the interactive specification of dynamically evaluated queries, which enable neuroscientists to pose and answer domain-specific questions in an intuitive manner. Queries are built step by step in a visual query builder, building more complex queries from combinations of simpler queries. Our application is based on a scalable volume visualization framework that scales to multiple volumes of several teravoxels each, enabling the concurrent visualization and querying of the original EM volume, additional segmentation volumes, neuronal connectivity, and additional meta data comprising a variety of neuronal data attributes. We evaluate our application on a data set of roughly one terabyte of EM data and 750 GB of segmentation data, containing over 4,000 segmented structures and 1,000 synapses. We demonstrate typical use-case scenarios of our collaborators in neuroscience, where our system has enabled them to answer specific scientific questions using interactive querying and analysis on the full-size data for the first time. © 1995-2012 IEEE.

Performance analysis of different tuning rules for an isothermal CSTR using integrated EPC and SPC

Science.gov (United States)

Roslan, A. H.; Karim, S. F. Abd; Hamzah, N.

2018-03-01

This paper demonstrates the integration of Engineering Process Control (EPC) and Statistical Process Control (SPC) for the control of product concentration of an isothermal CSTR. The objectives of this study are to evaluate the performance of Ziegler-Nichols (Z-N), Direct Synthesis, (DS) and Internal Model Control (IMC) tuning methods and determine the most effective method for this process. The simulation model was obtained from past literature and re-constructed using SIMULINK MATLAB to evaluate the process response. Additionally, the process stability, capability and normality were analyzed using Process Capability Sixpack reports in Minitab. Based on the results, DS displays the best response for having the smallest rise time, settling time, overshoot, undershoot, Integral Time Absolute Error (ITAE) and Integral Square Error (ISE). Also, based on statistical analysis, DS yields as the best tuning method as it exhibits the highest process stability and capability.

Tuning Catalytic Performance through a Single or Sequential Post-Synthesis Reaction(s) in a Gas Phase

Energy Technology Data Exchange (ETDEWEB)

Shan, Junjun [Department; Department; Zhang, Shiran [Department; Department; Choksi, Tej [Department; Nguyen, Luan [Department; Department; Bonifacio, Cecile S. [Department; Li, Yuanyuan [Department; Zhu, Wei [Department; Department; College; Tang, Yu [Department; Department; Zhang, Yawen [College; Yang, Judith C. [Department; Greeley, Jeffrey [Department; Frenkel, Anatoly I. [Department; Tao, Franklin [Department; Department

2016-12-05

Catalytic performance of a bimetallic catalyst is determined by geometric structure and electronic state of the surface or even the near-surface region of the catalyst. Here we report that single and sequential postsynthesis reactions of an as-synthesized bimetallic nanoparticle catalyst in one or more gas phases can tailor surface chemistry and structure of the catalyst in a gas phase, by which catalytic performance of this bimetallic catalyst can be tuned. Pt–Cu regular nanocube (Pt–Cu RNC) and concave nanocube (Pt–Cu CNC) are chosen as models of bimetallic catalysts. Surface chemistry and catalyst structure under different reaction conditions and during catalysis were explored in gas phase of one or two reactants with ambient-pressure X-ray photoelectron spectroscopy (AP-XPS) and extended X-ray absorption fine structure (EXAFS) spectroscopy. The newly formed surface structures of Pt–Cu RNC and Pt–Cu CNC catalysts strongly depend on the reactive gas(es) used in the postsynthesis reaction(s). A reaction of Pt–Cu RNC-as synthesized with H2 at 200 °C generates a near-surface alloy consisting of a Pt skin layer, a Cu-rich subsurface, and a Pt-rich deep layer. This near-surface alloy of Pt–Cu RNC-as synthesized-H2 exhibits a much higher catalytic activity in CO oxidation in terms of a low activation barrier of 39 ± 4 kJ/mol in contrast to 128 ± 7 kJ/mol of Pt–Cu RNC-as synthesized. Here the significant decrease of activation barrier demonstrates a method to tune catalytic performances of as-synthesized bimetallic catalysts. A further reaction of Pt–Cu RNC-as synthesized-H2 with CO forms a Pt–Cu alloy surface, which exhibits quite different catalytic performance in CO oxidation. It suggests the capability of generating a different surface by using another gas. The capability of tuning surface chemistry and structure of bimetallic catalysts was also demonstrated in restructuring of Pt–Cu CNC-as synthesized.

Path Minima Queries in Dynamic Weighted Trees

DEFF Research Database (Denmark)

Davoodi, Pooya; Brodal, Gerth Stølting; Satti, Srinivasa Rao

2011-01-01

In the path minima problem on a tree, each edge is assigned a weight and a query asks for the edge with minimum weight on a path between two nodes. For the dynamic version of the problem, where the edge weights can be updated, we give data structures that achieve optimal query time\\todo{what about...

Optimizing queries in SQL Server 2008

Directory of Open Access Journals (Sweden)

Ion LUNGU

2010-05-01

Full Text Available Starting from the need to develop efficient IT systems, we intend to review theoptimization methods and tools that can be used by SQL Server database administratorsand developers of applications based on Microsoft technology, focusing on the latestversion of the proprietary DBMS, SQL Server 2008. We’ll reflect on the objectives tobe considered in improving the performance of SQL Server instances, we will tackle themostly used techniques for analyzing and optimizing queries and we will describe the“Optimize for ad hoc workloads”, “Plan Freezing” and “Optimize for unknown" newoptions, accompanied by relevant code examples.

jQuery 2.0 animation techniques beginner's guide

CERN Document Server

Culpepper, Adam

2013-01-01

This book is a guide to help you create attractive web page animations using jQuery. Written in a friendly and engaging approach this book is designed to be placed alongside your computer as a mentor.If you are a web designer or a frontend developer or if you want to learn how to animate the user interface of your web applications with jQuery, this book is for you. Experience with jQuery or Javascript would be helpful but solid knowledge base of HTML and CSS is assumed.

An Adaptive Directed Query Dissemination Scheme for Wireless Sensor Networks

NARCIS (Netherlands)

Chatterjea, Supriyo; De Luigi, Simone; Havinga, Paul J.M.; Sun, M.T.

This paper describes a directed query dissemination scheme, DirQ that routes queries to the appropriate source nodes based on both constant and dynamicvalued attributes such as sensor types and sensor values. Unlike certain other query dissemination schemes, location information is not essential for

Querying Natural Logic Knowledge Bases

DEFF Research Database (Denmark)

Andreasen, Troels; Bulskov, Henrik; Jensen, Per Anker

2017-01-01

This paper describes the principles of a system applying natural logic as a knowledge base language. Natural logics are regimented fragments of natural language employing high level inference rules. We advocate the use of natural logic for knowledge bases dealing with querying of classes...... in ontologies and class-relationships such as are common in life-science descriptions. The paper adopts a version of natural logic with recursive restrictive clauses such as relative clauses and adnominal prepositional phrases. It includes passive as well as active voice sentences. We outline a prototype...... for partial translation of natural language into natural logic, featuring further querying and conceptual path finding in natural logic knowledge bases....

Seasonal trends in tinnitus symptomatology: evidence from Internet search engine query data.

Science.gov (United States)

Plante, David T; Ingram, David G

2015-10-01

The primary aim of this study was to test the hypothesis that the symptom of tinnitus demonstrates a seasonal pattern with worsening in the winter relative to the summer using Internet search engine query data. Normalized search volume for the term 'tinnitus' from January 2004 through December 2013 was retrieved from Google Trends. Seasonal effects were evaluated using cosinor regression models. Primary countries of interest were the United States and Australia. Secondary exploratory analyses were also performed using data from Germany, the United Kingdom, Canada, Sweden, and Switzerland. Significant seasonal effects for 'tinnitus' search queries were found in the United States and Australia (p search volume in the winter relative to the summer. Our findings indicate that there are significant seasonal trends for Internet search queries for tinnitus, with a zenith in winter months. Further research is indicated to determine the biological mechanisms underlying these findings, as they may provide insights into the pathophysiology of this common and debilitating medical symptom.

A Design Algorithm using External Perturbation to Improve Iterative Feedback Tuning Convergence

DEFF Research Database (Denmark)

Huusom, Jakob Kjøbsted; Hjalmarsson, Håkan; Poulsen, Niels Kjølstad

2011-01-01

Iterative Feedback Tuning constitutes an attractive control loop tuning method for processes in the absence of process insight. It is a purely data driven approach for optimization of the loop performance. The standard formulation ensures an unbiased estimate of the loop performance cost function...... gradient, which is used in a search algorithm for minimizing the performance cost. A slow rate of convergence of the tuning method is often experienced when tuning for disturbance rejection. This is due to a poor signal to noise ratio in the process data. A method is proposed for increasing the data...

Templates and Queries in Contextual Hypermedia

DEFF Research Database (Denmark)

Anderson, Kenneth Mark; Hansen, Frank Allan; Bouvin, Niels Olof

2006-01-01

discuss a framework, HyConSC, that implements this model and describe how it can be used to build new contextual hypermedia systems. Our framework aids the developer in the iterative development of contextual queries (via a dynamic query browser) and offers support for con-text matching, a key feature...... of contextual hypermedia. We have tested the framework with data and sensors taken from the HyCon contextual hypermedia system and are now migrating HyCon to this new framework....

Online control loop tuning in Pickering Nuclear Generating Stations

International Nuclear Information System (INIS)

Yu, K.X.; Harrington, S.

2008-01-01

Most analog controllers in the Pickering B Nuclear Generating Stations adopted PID control scheme. In replacing the analog controllers with digital controllers, the PID control strategies, including the original tuning parameters were retained. The replacement strategy resulted in minimum effort on control loop tuning. In a few cases, however, it was found during commissioning that control loop tuning was required as a result of poor control loop performance, typically due to slow response and controlled process oscillation. Several factors are accounted for the necessities of control loop re-tuning. Our experience in commissioning the digital controllers showed that online control tuning posted some challenges in nuclear power plant. (author)

Spatial Keyword Querying

DEFF Research Database (Denmark)

Cao, Xin; Chen, Lisi; Cong, Gao

2012-01-01

The web is increasingly being used by mobile users. In addition, it is increasingly becoming possible to accurately geo-position mobile users and web content. This development gives prominence to spatial web data management. Specifically, a spatial keyword query takes a user location and user-sup...... different kinds of functionality as well as the ideas underlying their definition....

Parallel Index and Query for Large Scale Data Analysis

Energy Technology Data Exchange (ETDEWEB)

Chou, Jerry; Wu, Kesheng; Ruebel, Oliver; Howison, Mark; Qiang, Ji; Prabhat,; Austin, Brian; Bethel, E. Wes; Ryne, Rob D.; Shoshani, Arie

2011-07-18

Modern scientific datasets present numerous data management and analysis challenges. State-of-the-art index and query technologies are critical for facilitating interactive exploration of large datasets, but numerous challenges remain in terms of designing a system for process- ing general scientific datasets. The system needs to be able to run on distributed multi-core platforms, efficiently utilize underlying I/O infrastructure, and scale to massive datasets. We present FastQuery, a novel software framework that address these challenges. FastQuery utilizes a state-of-the-art index and query technology (FastBit) and is designed to process mas- sive datasets on modern supercomputing platforms. We apply FastQuery to processing of a massive 50TB dataset generated by a large scale accelerator modeling code. We demonstrate the scalability of the tool to 11,520 cores. Motivated by the scientific need to search for inter- esting particles in this dataset, we use our framework to reduce search time from hours to tens of seconds.

Querying archetype-based EHRs by search ontology-based XPath engineering.

Science.gov (United States)

Kropf, Stefan; Uciteli, Alexandr; Schierle, Katrin; Krücken, Peter; Denecke, Kerstin; Herre, Heinrich

2018-05-11

Legacy data and new structured data can be stored in a standardized format as XML-based EHRs on XML databases. Querying documents on these databases is crucial for answering research questions. Instead of using free text searches, that lead to false positive results, the precision can be increased by constraining the search to certain parts of documents. A search ontology-based specification of queries on XML documents defines search concepts and relates them to parts in the XML document structure. Such query specification method is practically introduced and evaluated by applying concrete research questions formulated in natural language on a data collection for information retrieval purposes. The search is performed by search ontology-based XPath engineering that reuses ontologies and XML-related W3C standards. The key result is that the specification of research questions can be supported by the usage of search ontology-based XPath engineering. A deeper recognition of entities and a semantic understanding of the content is necessary for a further improvement of precision and recall. Key limitation is that the application of the introduced process requires skills in ontology and software development. In future, the time consuming ontology development could be overcome by implementing a new clinical role: the clinical ontologist. The introduced Search Ontology XML extension connects Search Terms to certain parts in XML documents and enables an ontology-based definition of queries. Search ontology-based XPath engineering can support research question answering by the specification of complex XPath expressions without deep syntax knowledge about XPaths.

Conceptual querying through ontologies

DEFF Research Database (Denmark)

Andreasen, Troels; Bulskov, Henrik

2009-01-01

is motivated by an obvious need for users to survey huge volumes of objects in query answers. An ontology formalism and a special notion of-instantiated ontology" are introduced. The latter is a structure reflecting the content in the document collection in that; it is a restriction of a general world......We present here ail approach to conceptual querying where the aim is, given a collection of textual database objects or documents, to target an abstraction of the entire database content in terms of the concepts appearing in documents, rather than the documents in the collection. The approach...... knowledge ontology to the concepts instantiated in the collection. The notion of ontology-based similarity is briefly described, language constructs for direct navigation and retrieval of concepts in the ontology are discussed and approaches to conceptual summarization are presented....

Constraint-based query distribution framework for an integrated global schema

DEFF Research Database (Denmark)

Malik, Ahmad Kamran; Qadir, Muhammad Abdul; Iftikhar, Nadeem

2009-01-01

and replicated data sources. The provided system is all XML-based which poses query in XML form, transforms, and integrates local results in an XML document. Contributions include the use of constraints in our existing global schema which help in source selection and query optimization, and a global query...

Parasol: An Architecture for Cross-Cloud Federated Graph Querying

Energy Technology Data Exchange (ETDEWEB)

Lieberman, Michael; Choudhury, Sutanay; Hughes, Marisa; Patrone, Dennis; Hider, Sandy; Piatko, Christine; Chapman, Matthew; Marple, JP; Silberberg, David

2014-06-22

Large scale data fusion of multiple datasets can often provide in- sights that examining datasets individually cannot. However, when these datasets reside in different data centers and cannot be collocated due to technical, administrative, or policy barriers, a unique set of problems arise that hamper querying and data fusion. To ad- dress these problems, a system and architecture named Parasol is presented that enables federated queries over graph databases residing in multiple clouds. Parasol’s design is flexible and requires only minimal assumptions for participant clouds. Query optimization techniques are also described that are compatible with Parasol’s lightweight architecture. Experiments on a prototype implementation of Parasol indicate its suitability for cross-cloud federated graph queries.

Labeling RDF Graphs for Linear Time and Space Querying

Science.gov (United States)

Furche, Tim; Weinzierl, Antonius; Bry, François

Indices and data structures for web querying have mostly considered tree shaped data, reflecting the view of XML documents as tree-shaped. However, for RDF (and when querying ID/IDREF constraints in XML) data is indisputably graph-shaped. In this chapter, we first study existing indexing and labeling schemes for RDF and other graph datawith focus on support for efficient adjacency and reachability queries. For XML, labeling schemes are an important part of the widespread adoption of XML, in particular for mapping XML to existing (relational) database technology. However, the existing indexing and labeling schemes for RDF (and graph data in general) sacrifice one of the most attractive properties of XML labeling schemes, the constant time (and per-node space) test for adjacency (child) and reachability (descendant). In the second part, we introduce the first labeling scheme for RDF data that retains this property and thus achieves linear time and space processing of acyclic RDF queries on a significantly larger class of graphs than previous approaches (which are mostly limited to tree-shaped data). Finally, we show how this labeling scheme can be applied to (acyclic) SPARQL queries to obtain an evaluation algorithm with time and space complexity linear in the number of resources in the queried RDF graph.

Concept-based query language approach to enterprise information systems

Science.gov (United States)

Niemi, Timo; Junkkari, Marko; Järvelin, Kalervo

2014-01-01

In enterprise information systems (EISs) it is necessary to model, integrate and compute very diverse data. In advanced EISs the stored data often are based both on structured (e.g. relational) and semi-structured (e.g. XML) data models. In addition, the ad hoc information needs of end-users may require the manipulation of data-oriented (structural), behavioural and deductive aspects of data. Contemporary languages capable of treating this kind of diversity suit only persons with good programming skills. In this paper we present a concept-oriented query language approach to manipulate this diversity so that the programming skill requirements are considerably reduced. In our query language, the features which need technical knowledge are hidden in application-specific concepts and structures. Therefore, users need not be aware of the underlying technology. Application-specific concepts and structures are represented by the modelling primitives of the extended RDOOM (relational deductive object-oriented modelling) which contains primitives for all crucial real world relationships (is-a relationship, part-of relationship, association), XML documents and views. Our query language also supports intensional and extensional-intensional queries, in addition to conventional extensional queries. In its query formulation, the end-user combines available application-specific concepts and structures through shared variables.

New ATLAS event generator tunes to 2010 data

CERN Document Server

The ATLAS collaboration

2011-01-01

This note describes the Monte Carlo event generator tunings for the Pythia 6 and Herwig/Jimmy generators in the ATLAS MC11 simulation production. New tunes have been produced for these generators, making maximal use of available published data from ATLAS and from the Tevatron and LEP experiments. Particular emphasis has been placed on improvement of the description of e+ e− event shape and jet rate data, and on description of hadron collider event shape observables in Pythia, as well as the established procedure of tuning the multiple parton interactions of both models to describe underlying event and minimum bias data. The tuning of Pythia is provided at this time for the MRST LO∗∗ PDF, while the purely MPI tune of Herwig/Jimmy is performed for ten different PDFs.

Efficient Processing of Multiple DTW Queries in Time Series Databases

DEFF Research Database (Denmark)

Kremer, Hardy; Günnemann, Stephan; Ivanescu, Anca-Maria

2011-01-01

. In many of today’s applications, however, large numbers of queries arise at any given time. Existing DTW techniques do not process multiple DTW queries simultaneously, a serious limitation which slows down overall processing. In this paper, we propose an efficient processing approach for multiple DTW...... for multiple DTW queries....

Advanced SPARQL querying in small molecule databases.

Science.gov (United States)

Galgonek, Jakub; Hurt, Tomáš; Michlíková, Vendula; Onderka, Petr; Schwarz, Jan; Vondrášek, Jiří

2016-01-01

In recent years, the Resource Description Framework (RDF) and the SPARQL query language have become more widely used in the area of cheminformatics and bioinformatics databases. These technologies allow better interoperability of various data sources and powerful searching facilities. However, we identified several deficiencies that make usage of such RDF databases restrictive or challenging for common users. We extended a SPARQL engine to be able to use special procedures inside SPARQL queries. This allows the user to work with data that cannot be simply precomputed and thus cannot be directly stored in the database. We designed an algorithm that checks a query against data ontology to identify possible user errors. This greatly improves query debugging. We also introduced an approach to visualize retrieved data in a user-friendly way, based on templates describing visualizations of resource classes. To integrate all of our approaches, we developed a simple web application. Our system was implemented successfully, and we demonstrated its usability on the ChEBI database transformed into RDF form. To demonstrate procedure call functions, we employed compound similarity searching based on OrChem. The application is publicly available at https://bioinfo.uochb.cas.cz/projects/chemRDF.

Efficient Storage and Querying of Horizontal Tables Using a PIVOT Operation in Commercial Relational DBMSs

Science.gov (United States)

Shin, Sung-Hyun; Moon, Yang-Sae; Kim, Jinho; Kim, Sang-Wook

In recent years, a horizontal table with a large number of attributes is widely used in OLAP or e-business applications to analyze multidimensional data efficiently. For efficient storing and querying of horizontal tables, recent works have tried to transform a horizontal table to a traditional vertical table. Existing works, however, have the drawback of not considering an optimized PIVOT operation provided (or to be provided) in recent commercial RDBMSs. In this paper we propose a formal approach that exploits the optimized PIVOT operation of commercial RDBMSs for storing and querying of horizontal tables. To achieve this goal, we first provide an overall framework that stores and queries a horizontal table using an equivalent vertical table. Under the proposed framework, we then formally define 1) a method that stores a horizontal table in an equivalent vertical table and 2) a PIVOT operation that converts a stored vertical table to an equivalent horizontal view. Next, we propose a novel method that transforms a user-specified query on horizontal tables to an equivalent PIVOT-included query on vertical tables. In particular, by providing transformation rules for all five elementary operations in relational algebra as theorems, we prove our method is theoretically applicable to commercial RDBMSs. Experimental results show that, compared with the earlier work, our method reduces storage space significantly and also improves average performance by several orders of magnitude. These results indicate that our method provides an excellent framework to maximize performance in handling horizontal tables by exploiting the optimized PIVOT operation in commercial RDBMSs.

Algebra-Based Optimization of XML-Extended OLAP Queries

DEFF Research Database (Denmark)

Yin, Xuepeng; Pedersen, Torben Bach

In today’s OLAP systems, integrating fast changing data, e.g., stock quotes, physically into a cube is complex and time-consuming. The widespread use of XML makes it very possible that this data is available in XML format on the WWW; thus, making XML data logically federated with OLAP systems...... is desirable. This report presents a complete foundation for such OLAP-XML federations. This includes a prototypical query engine, a simplified query semantics based on previous work, and a complete physical algebra which enables precise modeling of the execution tasks of an OLAP-XML query. Effective algebra...

QueryArch3D: Querying and Visualising 3D Models of a Maya Archaeological Site in a Web-Based Interface

Directory of Open Access Journals (Sweden)

Giorgio Agugiaro

2011-12-01

Full Text Available Constant improvements in the field of surveying, computing and distribution of digital-content are reshaping the way Cultural Heritage can be digitised and virtually accessed, even remotely via web. A traditional 2D approach for data access, exploration, retrieval and exploration may generally suffice, however more complex analyses concerning spatial and temporal features require 3D tools, which, in some cases, have not yet been implemented or are not yet generally commercially available. Efficient organisation and integration strategies applicable to the wide array of heterogeneous data in the field of Cultural Heritage represent a hot research topic nowadays. This article presents a visualisation and query tool (QueryArch3D conceived to deal with multi-resolution 3D models. Geometric data are organised in successive levels of detail (LoD, provided with geometric and semantic hierarchies and enriched with attributes coming from external data sources. The visualisation and query front-end enables the 3D navigation of the models in a virtual environment, as well as the interaction with the objects by means of queries based on attributes or on geometries. The tool can be used as a standalone application, or served through the web. The characteristics of the research work, along with some implementation issues and the developed QueryArch3D tool will be discussed and presented.

The SQL++ Query Language: Configurable, Unifying and Semi-structured

OpenAIRE

Ong, Kian Win; Papakonstantinou, Yannis; Vernoux, Romain

2014-01-01

NoSQL databases support semi-structured data, typically modeled as JSON. They also provide limited (but expanding) query languages. Their idiomatic, non-SQL language constructs, the many variations, and the lack of formal semantics inhibit deep understanding of the query languages, and also impede progress towards clean, powerful, declarative query languages. This paper specifies the syntax and semantics of SQL++, which is applicable to both JSON native stores and SQL databases. The SQL++ sem...

Path Index Based Keywords to SPARQL Query Transformation for Semantic Data Federations

Directory of Open Access Journals (Sweden)

Thilini Cooray

2016-06-01

Full Text Available Semantic web is a highly emerging research domain. Enhancing the ability of keyword query processing on Semantic Web data provides a huge support for familiarizing the usefulness of Semantic Web to the general public. Most of the existing approaches focus on just user keyword matching to RDF graphs and output the connecting elements as results. Semantic Web consists of SPARQL query language which can process queries more accurately and efficiently than general keyword matching. There are only about a couple of approaches available for transforming keyword queries to SPARQL. They basically rely on real time graph traversals? for identifying subgraphs which can connect user keywords. Those approaches are either limited to query processing on a single data store or a set of interlinked data sets. They have not focused on query processing on a federation of independent data sets which belongs to the same domain. This research proposes a Path Index based approach eliminating real time graph traversal for transforming keyword queries to SPARQL. We have introduced an ontology alignment based approach for keyword query transforming on a federation of RDF data stored using multiple heterogeneous vocabularies. Evaluation shows that the proposed approach have the ability to generate SPARQL queries which can provide highly relevant results for user keyword queries. The Path Index based query transformation approach has also achieved high efficiency compared to the existing approach.

Lazy Toggle PRM: A single-query approach to motion planning

KAUST Repository

Denny, Jory

2013-05-01

Probabilistic RoadMaps (PRMs) are quite suc-cessful in solving complex and high-dimensional motion plan-ning problems. While particularly suited for multiple-query scenarios and expansive spaces, they lack efficiency in both solving single-query scenarios and mapping narrow spaces. Two PRM variants separately tackle these gaps. Lazy PRM reduces the computational cost of roadmap construction for single-query scenarios by delaying roadmap validation until query time. Toggle PRM is well suited for mapping narrow spaces by mapping both Cfree and Cobst, which gives certain theoretical benefits. However, fully validating the two resulting roadmaps can be costly. We present a strategy, Lazy Toggle PRM, for integrating these two approaches into a method which is both suited for narrow passages and efficient single-query calculations. This simultaneously addresses two challenges of PRMs. Like Lazy PRM, Lazy Toggle PRM delays validation of roadmaps until query time, but if no path is found, the algorithm augments the roadmap using the Toggle PRM methodology. We demonstrate the effectiveness of Lazy Toggle PRM in a wide range of scenarios, including those with narrow passages and high descriptive complexity (e.g., those described by many triangles), concluding that it is more effective than existing methods in solving difficult queries. © 2013 IEEE.

Broader visual orientation tuning in patients with schizophrenia

Directory of Open Access Journals (Sweden)

Ariel eRokem

2011-11-01

Full Text Available Reduced gamma-aminobutyric acid (GABA levels in cerebral cortex are thought to contribute to information processing deficits in patients with schizophrenia (SZ, and we have previously reported lower in vivo GABA levels in the visual cortex of patients with SZ. GABA-mediated inhibition plays a role in sharpening orientation tuning of visual cortical neurons. Therefore, we predicted that tuning for visual stimulus orientation would be wider in SZ. We measured orientation tuning with a psychophysical procedure in which subjects performed a target detection task of a low-contrast oriented grating, following adaptation to a high-contrast grating. Contrast detection thresholds were determined for a range of adapter-target orientation offsets. For both SZ and healthy controls, contrast thresholds decreased as orientation offset increased, suggesting that this tuning curve reflects the selectivity of visual cortical neurons for stimulus orientation. After accounting for generalized deficits in task performance in SZ, there was no difference between patients and controls for detection of target stimuli having either the same orientation as the adapter or orientations far from the adapter. However, patients’ thresholds were significantly higher for intermediate adapter-target offsets. In addition, the mean width parameter of a Gaussian fit to the psychophysical orientation tuning curves was significantly larger for the patient group. We also present preliminary data relating visual cortical GABA levels, as measured with magnetic resonance spectroscopy, and orientation tuning width. These results suggest that our finding of broader orientation tuning in SZ may be due to diminished visual cortical GABA levels.

Efficient external memory structures for range-aggregate queries

DEFF Research Database (Denmark)

Agarwal, P.K.; Yang, J.; Arge, L.

2013-01-01

We present external memory data structures for efficiently answering range-aggregate queries. The range-aggregate problem is defined as follows: Given a set of weighted points in Rd, compute the aggregate of the weights of the points that lie inside a d-dimensional orthogonal query rectangle. The...

Entropy Based Analysis of DNS Query Traffic in the Campus Network

Directory of Open Access Journals (Sweden)

Dennis Arturo Ludeña Romaña

2008-10-01

Full Text Available We carried out the entropy based study on the DNS query traffic from the campus network in a university through January 1st, 2006 to March 31st, 2007. The results are summarized, as follows: (1 The source IP addresses- and query keyword-based entropies change symmetrically in the DNS query traffic from the outside of the campus network when detecting the spam bot activity on the campus network. On the other hand (2, the source IP addresses- and query keywordbased entropies change similarly each other when detecting big DNS query traffic caused by prescanning or distributed denial of service (DDoS attack from the campus network. Therefore, we can detect the spam bot and/or DDoS attack bot by only watching DNS query access traffic.

Top-k aggregation queries in large-scale distributed systems

OpenAIRE

Michel, Sebastian

2007-01-01

Distributed top-k query processing has recently become an essential functionality in a large number of emerging application classes like Internet traffic monitoring and Peer-to-Peer Web search. This work addresses efficient algorithms for distributed top-k queries in wide-area networks where the index lists for the attribute values (or text terms) of a query are distributed across a number of data peers. More precisely, in this thesis, we make the following distributions: We present the fa...

Controllable Fabrication of Amorphous Co-Ni Pyrophosphates for Tuning Electrochemical Performance in Supercapacitors.

Science.gov (United States)

Chen, Chen; Zhang, Ning; He, Yulu; Liang, Bo; Ma, Renzhi; Liu, Xiaohe

2016-09-07

Incorporation of two transition metals offers an effective method to enhance the electrochemical performance in supercapacitors for transition metal compound based electrodes. However, such a configuration is seldom concerned in pyrophosphates. Here, amorphous phase Co-Ni pyrophosphates are fabricated as electrodes in supercapacitors. Through controllably adjusting the ratios of Co and Ni as well as the calcination temperature, the electrochemical performance can be tuned. An optimized amorphous Ni-Co pyrophosphate exhibits much higher specific capacitance than monometallic Ni and Co pyrophosphates and shows excellent cycling ability. When employing Ni-Co pyrophosphates as positive electrode and activated carbon as a negative electrode, the fabricated asymmetric supercapacitor cell exhibits favorable capacitance and cycling ability. This study provides facile methods to improve the transition metal pyrophosphate electrodes for efficient electrodes in electrochemical energy storage devices.

Efficient receiver tuning using differential evolution strategies

Science.gov (United States)

Wheeler, Caleb H.; Toland, Trevor G.

2016-08-01

Differential evolution (DE) is a powerful and computationally inexpensive optimization strategy that can be used to search an entire parameter space or to converge quickly on a solution. The Kilopixel Array Pathfinder Project (KAPPa) is a heterodyne receiver system delivering 5 GHz of instantaneous bandwidth in the tuning range of 645-695 GHz. The fully automated KAPPa receiver test system finds optimal receiver tuning using performance feedback and DE. We present an adaptation of DE for use in rapid receiver characterization. The KAPPa DE algorithm is written in Python 2.7 and is fully integrated with the KAPPa instrument control, data processing, and visualization code. KAPPa develops the technologies needed to realize heterodyne focal plane arrays containing 1000 pixels. Finding optimal receiver tuning by investigating large parameter spaces is one of many challenges facing the characterization phase of KAPPa. This is a difficult task via by-hand techniques. Characterizing or tuning in an automated fashion without need for human intervention is desirable for future large scale arrays. While many optimization strategies exist, DE is ideal for time and performance constraints because it can be set to converge to a solution rapidly with minimal computational overhead. We discuss how DE is utilized in the KAPPa system and discuss its performance and look toward the future of 1000 pixel array receivers and consider how the KAPPa DE system might be applied.

Query-by-example surgical activity detection.

Science.gov (United States)

Gao, Yixin; Vedula, S Swaroop; Lee, Gyusung I; Lee, Mija R; Khudanpur, Sanjeev; Hager, Gregory D

2016-06-01

Easy acquisition of surgical data opens many opportunities to automate skill evaluation and teaching. Current technology to search tool motion data for surgical activity segments of interest is limited by the need for manual pre-processing, which can be prohibitive at scale. We developed a content-based information retrieval method, query-by-example (QBE), to automatically detect activity segments within surgical data recordings of long duration that match a query. The example segment of interest (query) and the surgical data recording (target trial) are time series of kinematics. Our approach includes an unsupervised feature learning module using a stacked denoising autoencoder (SDAE), two scoring modules based on asymmetric subsequence dynamic time warping (AS-DTW) and template matching, respectively, and a detection module. A distance matrix of the query against the trial is computed using the SDAE features, followed by AS-DTW combined with template scoring, to generate a ranked list of candidate subsequences (substrings). To evaluate the quality of the ranked list against the ground-truth, thresholding conventional DTW distances and bipartite matching are applied. We computed the recall, precision, F1-score, and a Jaccard index-based score on three experimental setups. We evaluated our QBE method using a suture throw maneuver as the query, on two tool motion datasets (JIGSAWS and MISTIC-SL) captured in a training laboratory. We observed a recall of 93, 90 and 87 % and a precision of 93, 91, and 88 % with same surgeon same trial (SSST), same surgeon different trial (SSDT) and different surgeon (DS) experiment setups on JIGSAWS, and a recall of 87, 81 and 75 % and a precision of 72, 61, and 53 % with SSST, SSDT and DS experiment setups on MISTIC-SL, respectively. We developed a novel, content-based information retrieval method to automatically detect multiple instances of an activity within long surgical recordings. Our method demonstrated adequate recall

QCS: a system for querying, clustering and summarizing documents.

Energy Technology Data Exchange (ETDEWEB)

Dunlavy, Daniel M.; Schlesinger, Judith D. (Center for Computing Sciences, Bowie, MD); O' Leary, Dianne P. (University of Maryland, College Park, MD); Conroy, John M. (Center for Computing Sciences, Bowie, MD)

2006-10-01

Information retrieval systems consist of many complicated components. Research and development of such systems is often hampered by the difficulty in evaluating how each particular component would behave across multiple systems. We present a novel hybrid information retrieval system--the Query, Cluster, Summarize (QCS) system--which is portable, modular, and permits experimentation with different instantiations of each of the constituent text analysis components. Most importantly, the combination of the three types of components in the QCS design improves retrievals by providing users more focused information organized by topic. We demonstrate the improved performance by a series of experiments using standard test sets from the Document Understanding Conferences (DUC) along with the best known automatic metric for summarization system evaluation, ROUGE. Although the DUC data and evaluations were originally designed to test multidocument summarization, we developed a framework to extend it to the task of evaluation for each of the three components: query, clustering, and summarization. Under this framework, we then demonstrate that the QCS system (end-to-end) achieves performance as good as or better than the best summarization engines. Given a query, QCS retrieves relevant documents, separates the retrieved documents into topic clusters, and creates a single summary for each cluster. In the current implementation, Latent Semantic Indexing is used for retrieval, generalized spherical k-means is used for the document clustering, and a method coupling sentence 'trimming', and a hidden Markov model, followed by a pivoted QR decomposition, is used to create a single extract summary for each cluster. The user interface is designed to provide access to detailed information in a compact and useful format. Our system demonstrates the feasibility of assembling an effective IR system from existing software libraries, the usefulness of the modularity of the design

QCS : a system for querying, clustering, and summarizing documents.

Energy Technology Data Exchange (ETDEWEB)

Dunlavy, Daniel M.

2006-08-01

Information retrieval systems consist of many complicated components. Research and development of such systems is often hampered by the difficulty in evaluating how each particular component would behave across multiple systems. We present a novel hybrid information retrieval system--the Query, Cluster, Summarize (QCS) system--which is portable, modular, and permits experimentation with different instantiations of each of the constituent text analysis components. Most importantly, the combination of the three types of components in the QCS design improves retrievals by providing users more focused information organized by topic. We demonstrate the improved performance by a series of experiments using standard test sets from the Document Understanding Conferences (DUC) along with the best known automatic metric for summarization system evaluation, ROUGE. Although the DUC data and evaluations were originally designed to test multidocument summarization, we developed a framework to extend it to the task of evaluation for each of the three components: query, clustering, and summarization. Under this framework, we then demonstrate that the QCS system (end-to-end) achieves performance as good as or better than the best summarization engines. Given a query, QCS retrieves relevant documents, separates the retrieved documents into topic clusters, and creates a single summary for each cluster. In the current implementation, Latent Semantic Indexing is used for retrieval, generalized spherical k-means is used for the document clustering, and a method coupling sentence ''trimming'', and a hidden Markov model, followed by a pivoted QR decomposition, is used to create a single extract summary for each cluster. The user interface is designed to provide access to detailed information in a compact and useful format. Our system demonstrates the feasibility of assembling an effective IR system from existing software libraries, the usefulness of the modularity of

Performance Costs when Emotion Tunes Inappropriate Cognitive Abilities: Implications for Mental Resources and Behavior

Science.gov (United States)

Storbeck, Justin

2012-01-01

Emotion tunes cognition, such that approach-motivated positive states promote verbal cognition, whereas withdrawal-motivated negative states promote spatial cognition (Gray, 2001). The current research examined whether self-control resources become depleted and influence subsequent behavior when emotion tunes an inappropriate cognitive tendency.…

Ensemble learned vaccination uptake prediction using web search queries

DEFF Research Database (Denmark)

Hansen, Niels Dalum; Lioma, Christina; Mølbak, Kåre

2016-01-01

We present a method that uses ensemble learning to combine clinical and web-mined time-series data in order to predict future vaccination uptake. The clinical data is official vaccination registries, and the web data is query frequencies collected from Google Trends. Experiments with official...... vaccine records show that our method predicts vaccination uptake eff?ectively (4.7 Root Mean Squared Error). Whereas performance is best when combining clinical and web data, using solely web data yields comparative performance. To our knowledge, this is the ?first study to predict vaccination uptake...

Auto-tuning Non-blocking Collective Communication Operations

KAUST Repository

Barigou, Youcef; Venkatesan, Vishwanath; Gabriel, Edgar

2015-01-01

Collective operations are widely used in large scale scientific applications, and critical to the scalability of these applications for large process counts. It has also been demonstrated that collective operations have to be carefully tuned for a given platform and application scenario to maximize their performance. Non-blocking collective operations extend the concept of collective operations by offering the additional benefit of being able to overlap communication and computation. This paper presents the automatic run-time tuning of non-blocking collective communication operations, which allows the communication library to choose the best performing implementation for a non-blocking collective operation on a case by case basis. The paper demonstrates that libraries using a single algorithm or implementation for a non-blocking collective operation will inevitably lead to suboptimal performance in many scenarios, and thus validate the necessity for run-time tuning of these operations. The benefits of the approach are further demonstrated for an application kernel using a multi-dimensional Fast Fourier Transform. The results obtained for the application scenario indicate a performance improvement of up to 40% compared to the current state of the art.

Auto-tuning Non-blocking Collective Communication Operations

KAUST Repository

Barigou, Youcef

2015-05-01

Collective operations are widely used in large scale scientific applications, and critical to the scalability of these applications for large process counts. It has also been demonstrated that collective operations have to be carefully tuned for a given platform and application scenario to maximize their performance. Non-blocking collective operations extend the concept of collective operations by offering the additional benefit of being able to overlap communication and computation. This paper presents the automatic run-time tuning of non-blocking collective communication operations, which allows the communication library to choose the best performing implementation for a non-blocking collective operation on a case by case basis. The paper demonstrates that libraries using a single algorithm or implementation for a non-blocking collective operation will inevitably lead to suboptimal performance in many scenarios, and thus validate the necessity for run-time tuning of these operations. The benefits of the approach are further demonstrated for an application kernel using a multi-dimensional Fast Fourier Transform. The results obtained for the application scenario indicate a performance improvement of up to 40% compared to the current state of the art.

Tuning of the PI Controller Parameters of a PMSG Wind Turbine to Improve Control Performance under Various Wind Speeds

Directory of Open Access Journals (Sweden)

Yun-Su Kim

2015-02-01

Full Text Available This paper presents a method to seek the PI controller parameters of a PMSG wind turbine to improve control performance. Since operating conditions vary with the wind speed, therefore the PI controller parameters should be determined as a function of the wind speed. Small-signal modeling of a PMSG WT is implemented to analyze the stability under various operating conditions and with eigenvalues obtained from the small-signal model of the PMSG WT, which are coordinated by adjusting the PI controller parameters. The parameters to be tuned are chosen by investigating participation factors of state variables, which simplifies the problem by reducing the number of parameters to be tuned. The process of adjusting these PI controller parameters is carried out using particle swarm optimization (PSO. To characterize the improvements in the control method due to the PSO method of tuning the PI controller parameters, the PMSG WT is modeled using the MATLAB/SimPowerSystems libraries with the obtained PI controller parameters.

Geometric Representations of Condition Queries on Three-Dimensional Vector Fields

Science.gov (United States)

Henze, Chris

1999-01-01

Condition queries on distributed data ask where particular conditions are satisfied. It is possible to represent condition queries as geometric objects by plotting field data in various spaces derived from the data, and by selecting loci within these derived spaces which signify the desired conditions. Rather simple geometric partitions of derived spaces can represent complex condition queries because much complexity can be encapsulated in the derived space mapping itself A geometric view of condition queries provides a useful conceptual unification, allowing one to intuitively understand many existing vector field feature detection algorithms -- and to design new ones -- as variations on a common theme. A geometric representation of condition queries also provides a simple and coherent basis for computer implementation, reducing a wide variety of existing and potential vector field feature detection techniques to a few simple geometric operations.

Efficient processing of containment queries on nested sets

NARCIS (Netherlands)

Ibrahim, A.; Fletcher, G.H.L.

2013-01-01

We study the problem of computing containment queries on sets which can have both atomic and set-valued objects as elements, i.e., nested sets. Containment is a fundamental query pattern with many basic applications. Our study of nested set containment is motivated by the ubiquity of nested data in

Ontology Based Queries - Investigating a Natural Language Interface

NARCIS (Netherlands)

van der Sluis, Ielka; Hielkema, F.; Mellish, C.; Doherty, G.

2010-01-01

In this paper we look at what may be learned from a comparative study examining non-technical users with a background in social science browsing and querying metadata. Four query tasks were carried out with a natural language interface and with an interface that uses a web paradigm with hyperlinks.

Towards Automatic Improvement of Patient Queries in Health Retrieval Systems

Directory of Open Access Journals (Sweden)

Nesrine KSENTINI

2016-07-01

Full Text Available With the adoption of health information technology for clinical health, e-health is becoming usual practice today. Users of this technology find it difficult to seek information relevant to their needs due to the increasing amount of the clinical and medical data on the web, and the lack of knowledge of medical jargon. In this regards, a method is described to improve user's needs by automatically adding new related terms to their queries which appear in the same context of the original query in order to improve final search results. This method is based on the assessment of semantic relationships defined by a proposed statistical method between a set of terms or keywords. Experiments were performed on CLEF-eHealth-2015 database and the obtained results show the effectiveness of our proposed method.

Tune-Based Halo Diagnostics

International Nuclear Information System (INIS)

Cameron, Peter

2003-01-01

Tune-based halo diagnostics can be divided into two categories -- diagnostics for halo prevention, and diagnostics for halo measurement. Diagnostics for halo prevention are standard fare in accumulators, synchrotrons, and storage rings, and again can be divided into two categories -- diagnostics to measure the tune distribution (primarily to avoid resonances), and diagnostics to identify instabilities (which will not be discussed here). These diagnostic systems include kicked (coherent) tune measurement, phase-locked loop (PLL) tune measurement, Schottky tune measurement, beam transfer function (BTF) measurements, and measurement of transverse quadrupole mode envelope oscillations. We refer briefly to tune diagnostics used at RHIC and intended for the SNS, and then present experimental results. Tune-based diagnostics for halo measurement (as opposed to prevention) are considerably more difficult. We present one brief example of tune-based halo measurement

Discrete PID Tuning Using Artificial Intelligence Techniques

Directory of Open Access Journals (Sweden)

Petr DOLEŽEL

2009-06-01

Full Text Available PID controllers are widely used in industry these days due to their useful properties such as simple tuning or robustness. While they are applicable to many control problems, they can perform poorly in some applications. Highly nonlinear system control with constrained manipulated variable can be mentioned as an example. The point of the paper is to string together convenient qualities of conventional PID control and progressive techniques based on Artificial Intelligence. Proposed control method should deal with even highly nonlinear systems. To be more specific, there is described new method of discrete PID controller tuning in this paper. This method tunes discrete PID controller parameters online through the use of genetic algorithm and neural model of controlled system in order to control successfully even highly nonlinear systems. After method description and some discussion, there is performed control simulation and comparison to one chosen conventional control method.

Incentives for Delay-Constrained Data Query and Feedback in Mobile Opportunistic Crowdsensing

Directory of Open Access Journals (Sweden)

Yang Liu

2016-07-01

Full Text Available In this paper, we propose effective data collection schemes that stimulate cooperation between selfish users in mobile opportunistic crowdsensing. A query issuer generates a query and requests replies within a given delay budget. When a data provider receives the query for the first time from an intermediate user, the former replies to it and authorizes the latter as the owner of the reply. Different data providers can reply to the same query. When a user that owns a reply meets the query issuer that generates the query, it requests the query issuer to pay credits. The query issuer pays credits and provides feedback to the data provider, which gives the reply. When a user that carries a feedback meets the data provider, the data provider pays credits to the user in order to adjust its claimed expertise. Queries, replies and feedbacks can be traded between mobile users. We propose an effective mechanism to define rewards for queries, replies and feedbacks. We formulate the bargain process as a two-person cooperative game, whose solution is found by using the Nash theorem. To improve the credit circulation, we design an online auction process, in which the wealthy user can buy replies and feedbacks from the starving one using credits. We have carried out extensive simulations based on real-world traces to evaluate the proposed schemes.

Tuning of PID load frequency controller for power systems

International Nuclear Information System (INIS)

Tan Wen

2009-01-01

PID tuning of load frequency controllers for power systems is discussed in this paper. The tuning method is based on a two-degree-of-freedom internal model control (IMC) design method, and the performance of the resulting PID controller is related to two tuning parameters thus detuning is easy when necessary. Then an anti-GRC scheme is proposed to overcome the generation rate constraints. Finally, the method is extended to two-area cases.

Schedule Sales Query Raw Data

Data.gov (United States)

General Services Administration — Schedule Sales Query presents sales volume figures as reported to GSA by contractors. The reports are generated as quarterly reports for the current year and the...

Flexible Query Answering Systems

DEFF Research Database (Denmark)

This book constitutes the refereed proceedings of the 12th International Conference on Flexible Query Answering Systems, FQAS 2017, held in London, UK, in June 2017. The 21 full papers presented in this book together with 4 short papers were carefully reviewed and selected from 43 submissions...

Performance characterization of a pressure-tuned wide-angle Michelson interferometric spectral filter for high spectral resolution lidar

Science.gov (United States)

Seaman, Shane T.; Cook, Anthony L.; Scola, Salvatore J.; Hostetler, Chris A.; Miller, Ian; Welch, Wayne

2015-09-01

High Spectral Resolution Lidar (HSRL) is typically realized using an absorption filter to separate molecular returns from particulate returns. NASA Langley Research Center (LaRC) has designed and built a Pressure-Tuned Wide-Angle Michelson Interferometer (PTWAMI) as an alternate means to separate the two types of atmospheric returns. While absorption filters only work at certain wavelengths and suffer from low photon efficiency due to light absorption, an interferometric spectral filter can be designed for any wavelength and transmits nearly all incident photons. The interferometers developed at LaRC employ an air spacer in one arm, and a solid glass spacer in the other. Field widening is achieved by specific design and selection of the lengths and refractive indices of these two arms. The principal challenge in using such an interferometer as a spectral filter for HSRL aboard aircraft is that variations in glass temperature and air pressure cause changes in the interferometer's optical path difference. Therefore, a tuning mechanism is needed to actively accommodate for these changes. The pressure-tuning mechanism employed here relies on changing the pressure in an enclosed, air-filled arm of the interferometer to change the arm's optical path length. However, tuning using pressure will not adjust for tilt, mirror warpage, or thermally induced wavefront error, so the structural, thermal, and optical behavior of the device must be well understood and optimized in the design and manufacturing process. The PTWAMI has been characterized for particulate transmission ratio, wavefront error, and tilt, and shows acceptable performance for use in an HSRL instrument.

Using ontology databases for scalable query answering, inconsistency detection, and data integration

Science.gov (United States)

Dou, Dejing

2011-01-01

An ontology database is a basic relational database management system that models an ontology plus its instances. To reason over the transitive closure of instances in the subsumption hierarchy, for example, an ontology database can either unfold views at query time or propagate assertions using triggers at load time. In this paper, we use existing benchmarks to evaluate our method—using triggers—and we demonstrate that by forward computing inferences, we not only improve query time, but the improvement appears to cost only more space (not time). However, we go on to show that the true penalties were simply opaque to the benchmark, i.e., the benchmark inadequately captures load-time costs. We have applied our methods to two case studies in biomedicine, using ontologies and data from genetics and neuroscience to illustrate two important applications: first, ontology databases answer ontology-based queries effectively; second, using triggers, ontology databases detect instance-based inconsistencies—something not possible using views. Finally, we demonstrate how to extend our methods to perform data integration across multiple, distributed ontology databases. PMID:22163378

A Novel Query Method for Spatial Data in Mobile Cloud Computing Environment

Directory of Open Access Journals (Sweden)

Guangsheng Chen

2018-01-01

Full Text Available With the development of network communication, a 1000-fold increase in traffic demand from 4G to 5G, it is critical to provide efficient and fast spatial data access interface for applications in mobile environment. In view of the low I/O efficiency and high latency of existing methods, this paper presents a memory-based spatial data query method that uses the distributed memory file system Alluxio to store data and build a two-level index based on the Alluxio key-value structure; moreover, it aims to solve the problem of low efficiency of traditional method; according to the characteristics of Spark computing framework, a data input format for spatial data query is proposed, which can selectively read the file data and reduce the data I/O. The comparative experiments show that the memory-based file system Alluxio has better I/O performance than the disk file system; compared with the traditional distributed query method, the method we proposed reduces the retrieval time greatly.

Enhancing Photocatalytic Performance through Tuning the Interfacial Process between -Assembled and Pt-Loaded Microspheres

Directory of Open Access Journals (Sweden)

Jun Zhang

2012-01-01

Full Text Available This work reports on a simple two-step approach to rutile TiO2-assembled microspheres loaded by Pt with an aim to tune semiconductor-metal interfacial processes for enhancing the photocatalytic performance. Systematic sample characterizations and structural analysis indicate that Pt loading did not produce any significant influences on the lattice structure of TiO2-assembled microspheres. Instead, upon Pt loading, Schottky barrier was formed in the interfaces between microspheres and Pt nanoparticles, which inhabited efficiently the recombination of photo-generated electron-hole pairs essential for the photocatalytic activities. In addition, TiO2 microspheres also showed a capacity of electrons storage and releasing as represented by a high dielectric constant, which increased the utility rate of photogenerated electrons. All these structural advantages contribute to the excellent photocatalytic activity under ultraviolet light irradiation. The interfacial process between microspheres and Pt nanoparticles was further tuned through adjusting the loading Pt content of metal Pt. As a consequence, the best photocatalytic activity on TiO2 was obtained at 0.85 wt% Pt loading, above or below which photocatalytic activity was apparently decreased.

Multiple k Nearest Neighbor Query Processing in Spatial Network Databases

DEFF Research Database (Denmark)

Xuegang, Huang; Jensen, Christian Søndergaard; Saltenis, Simonas

2006-01-01

This paper concerns the efficient processing of multiple k nearest neighbor queries in a road-network setting. The assumed setting covers a range of scenarios such as the one where a large population of mobile service users that are constrained to a road network issue nearest-neighbor queries...... for points of interest that are accessible via the road network. Given multiple k nearest neighbor queries, the paper proposes progressive techniques that selectively cache query results in main memory and subsequently reuse these for query processing. The paper initially proposes techniques for the case...... where an upper bound on k is known a priori and then extends the techniques to the case where this is not so. Based on empirical studies with real-world data, the paper offers insight into the circumstances under which the different proposed techniques can be used with advantage for multiple k nearest...

Query Log Analysis of an Electronic Health Record Search Engine

Science.gov (United States)

Yang, Lei; Mei, Qiaozhu; Zheng, Kai; Hanauer, David A.

2011-01-01

We analyzed a longitudinal collection of query logs of a full-text search engine designed to facilitate information retrieval in electronic health records (EHR). The collection, 202,905 queries and 35,928 user sessions recorded over a course of 4 years, represents the information-seeking behavior of 533 medical professionals, including frontline practitioners, coding personnel, patient safety officers, and biomedical researchers for patient data stored in EHR systems. In this paper, we present descriptive statistics of the queries, a categorization of information needs manifested through the queries, as well as temporal patterns of the users’ information-seeking behavior. The results suggest that information needs in medical domain are substantially more sophisticated than those that general-purpose web search engines need to accommodate. Therefore, we envision there exists a significant challenge, along with significant opportunities, to provide intelligent query recommendations to facilitate information retrieval in EHR. PMID:22195150

Parallel main-memory indexing for moving-object query and update workloads

DEFF Research Database (Denmark)

Sidlauskas, Darius; Saltenis, Simonas; Jensen, Christian Søndergaard

2012-01-01

of supporting the location-related query and update workloads generated by very large populations of such moving objects. This paper presents a main-memory indexing technique that aims to support such workloads. The technique, called PGrid, uses a grid structure that is capable of exploiting the parallelism...... offered by modern processors. Unlike earlier proposals that maintain separate structures for updates and queries, PGrid allows both long-running queries and rapid updates to operate on a single data structure and thus offers up-to-date query results. Because PGrid does not rely on creating snapshots...... on the same current data-store state, PGrid outperforms snapshot-based techniques in terms of both query freshness and CPU cycle-wise efficiency....

VPipe: Virtual Pipelining for Scheduling of DAG Stream Query Plans

Science.gov (United States)

Wang, Song; Gupta, Chetan; Mehta, Abhay

There are data streams all around us that can be harnessed for tremendous business and personal advantage. For an enterprise-level stream processing system such as CHAOS [1] (Continuous, Heterogeneous Analytic Over Streams), handling of complex query plans with resource constraints is challenging. While several scheduling strategies exist for stream processing, efficient scheduling of complex DAG query plans is still largely unsolved. In this paper, we propose a novel execution scheme for scheduling complex directed acyclic graph (DAG) query plans with meta-data enriched stream tuples. Our solution, called Virtual Pipelined Chain (or VPipe Chain for short), effectively extends the "Chain" pipelining scheduling approach to complex DAG query plans.

A hierarchical recurrent encoder-decoder for generative context-aware query suggestion

DEFF Research Database (Denmark)

Sordoni, Alessandro; Bengio, Yoshua; Vahabi, Hossein

2015-01-01

Users may strive to formulate an adequate textual query for their information need. Search engines assist the users by presenting query suggestions. To preserve the original search intent, suggestions should be context-aware and account for the previous queries issued by the user. Achieving context...

Bat-Inspired Algorithm Based Query Expansion for Medical Web Information Retrieval.

Science.gov (United States)

Khennak, Ilyes; Drias, Habiba

2017-02-01

With the increasing amount of medical data available on the Web, looking for health information has become one of the most widely searched topics on the Internet. Patients and people of several backgrounds are now using Web search engines to acquire medical information, including information about a specific disease, medical treatment or professional advice. Nonetheless, due to a lack of medical knowledge, many laypeople have difficulties in forming appropriate queries to articulate their inquiries, which deem their search queries to be imprecise due the use of unclear keywords. The use of these ambiguous and vague queries to describe the patients' needs has resulted in a failure of Web search engines to retrieve accurate and relevant information. One of the most natural and promising method to overcome this drawback is Query Expansion. In this paper, an original approach based on Bat Algorithm is proposed to improve the retrieval effectiveness of query expansion in medical field. In contrast to the existing literature, the proposed approach uses Bat Algorithm to find the best expanded query among a set of expanded query candidates, while maintaining low computational complexity. Moreover, this new approach allows the determination of the length of the expanded query empirically. Numerical results on MEDLINE, the on-line medical information database, show that the proposed approach is more effective and efficient compared to the baseline.

A Caveat Note on Tuning in the Development of Coupled Climate Models

Science.gov (United States)

Dommenget, Dietmar; Rezny, Michael

2018-01-01

State-of-the-art coupled general circulation models (CGCMs) have substantial errors in their simulations of climate. In particular, these errors can lead to large uncertainties in the simulated climate response (both globally and regionally) to a doubling of CO2. Currently, tuning of the parameterization schemes in CGCMs is a significant part of the developed. It is not clear whether such tuning actually improves models. The tuning process is (in general) neither documented, nor reproducible. Alternative methods such as flux correcting are not used nor is it clear if such methods would perform better. In this study, ensembles of perturbed physics experiments are performed with the Globally Resolved Energy Balance (GREB) model to test the impact of tuning. The work illustrates that tuning has, in average, limited skill given the complexity of the system, the limited computing resources, and the limited observations to optimize parameters. While tuning may improve model performance (such as reproducing observed past climate), it will not get closer to the "true" physics nor will it significantly improve future climate change projections. Tuning will introduce artificial compensating error interactions between submodels that will hamper further model development. In turn, flux corrections do perform well in most, but not all aspects. A main advantage of flux correction is that it is much cheaper, simpler, more transparent, and it does not introduce artificial error interactions between submodels. These GREB model experiments should be considered as a pilot study to motivate further CGCM studies that address the issues of model tuning.

PERI - auto-tuning memory-intensive kernels for multicore

International Nuclear Information System (INIS)

Williams, S; Carter, J; Oliker, L; Shalf, J; Yelick, K; Bailey, D; Datta, K

2008-01-01

We present an auto-tuning approach to optimize application performance on emerging multicore architectures. The methodology extends the idea of search-based performance optimizations, popular in linear algebra and FFT libraries, to application-specific computational kernels. Our work applies this strategy to sparse matrix vector multiplication (SpMV), the explicit heat equation PDE on a regular grid (Stencil), and a lattice Boltzmann application (LBMHD). We explore one of the broadest sets of multicore architectures in the high-performance computing literature, including the Intel Xeon Clovertown, AMD Opteron Barcelona, Sun Victoria Falls, and the Sony-Toshiba-IBM (STI) Cell. Rather than hand-tuning each kernel for each system, we develop a code generator for each kernel that allows us identify a highly optimized version for each platform, while amortizing the human programming effort. Results show that our auto-tuned kernel applications often achieve a better than 4x improvement compared with the original code. Additionally, we analyze a Roofline performance model for each platform to reveal hardware bottlenecks and software challenges for future multicore systems and applications

SPARQLGraph: a web-based platform for graphically querying biological Semantic Web databases.

Science.gov (United States)

Schweiger, Dominik; Trajanoski, Zlatko; Pabinger, Stephan

2014-08-15

Semantic Web has established itself as a framework for using and sharing data across applications and database boundaries. Here, we present a web-based platform for querying biological Semantic Web databases in a graphical way. SPARQLGraph offers an intuitive drag & drop query builder, which converts the visual graph into a query and executes it on a public endpoint. The tool integrates several publicly available Semantic Web databases, including the databases of the just recently released EBI RDF platform. Furthermore, it provides several predefined template queries for answering biological questions. Users can easily create and save new query graphs, which can also be shared with other researchers. This new graphical way of creating queries for biological Semantic Web databases considerably facilitates usability as it removes the requirement of knowing specific query languages and database structures. The system is freely available at http://sparqlgraph.i-med.ac.at.

The Ontology Lookup Service, a lightweight cross-platform tool for controlled vocabulary queries

Directory of Open Access Journals (Sweden)

Apweiler Rolf

2006-02-01

Full Text Available Abstract Background With the vast amounts of biomedical data being generated by high-throughput analysis methods, controlled vocabularies and ontologies are becoming increasingly important to annotate units of information for ease of search and retrieval. Each scientific community tends to create its own locally available ontology. The interfaces to query these ontologies tend to vary from group to group. We saw the need for a centralized location to perform controlled vocabulary queries that would offer both a lightweight web-accessible user interface as well as a consistent, unified SOAP interface for automated queries. Results The Ontology Lookup Service (OLS was created to integrate publicly available biomedical ontologies into a single database. All modified ontologies are updated daily. A list of currently loaded ontologies is available online. The database can be queried to obtain information on a single term or to browse a complete ontology using AJAX. Auto-completion provides a user-friendly search mechanism. An AJAX-based ontology viewer is available to browse a complete ontology or subsets of it. A programmatic interface is available to query the webservice using SOAP. The service is described by a WSDL descriptor file available online. A sample Java client to connect to the webservice using SOAP is available for download from SourceForge. All OLS source code is publicly available under the open source Apache Licence. Conclusion The OLS provides a user-friendly single entry point for publicly available ontologies in the Open Biomedical Ontology (OBO format. It can be accessed interactively or programmatically at http://www.ebi.ac.uk/ontology-lookup/.

On (dynamic) range minimum queries in external memory

DEFF Research Database (Denmark)

Arge, L.; Fischer, Johannes; Sanders, Peter

2013-01-01

We study the one-dimensional range minimum query (RMQ) problem in the external memory model. We provide the first space-optimal solution to the batched static version of the problem. On an instance with N elements and Q queries, our solution takes Θ(sort(N + Q)) = Θ( N+QB log M /B N+QB ) I...

Menangkal Serangan SQL Injection Dengan Parameterized Query

Directory of Open Access Journals (Sweden)

Yulianingsih Yulianingsih

2016-06-01

Full Text Available Semakin meningkat pertumbuhan layanan informasi maka semakin tinggi pula tingkat kerentanan keamanan dari suatu sumber informasi. Melalui tulisan ini disajikan penelitian yang dilakukan secara eksperimen yang membahas tentang kejahatan penyerangan database secara SQL Injection. Penyerangan dilakukan melalui halaman autentikasi dikarenakan halaman ini merupakan pintu pertama akses yang seharusnya memiliki pertahanan yang cukup. Kemudian dilakukan eksperimen terhadap metode Parameterized Query untuk mendapatkan solusi terhadap permasalahan tersebut.   Kata kunci— Layanan Informasi, Serangan, eksperimen, SQL Injection, Parameterized Query.

ECG signal performance de-noising assessment based on threshold tuning of dual-tree wavelet transform.

Science.gov (United States)

El B'charri, Oussama; Latif, Rachid; Elmansouri, Khalifa; Abenaou, Abdenbi; Jenkal, Wissam

2017-02-07

Since the electrocardiogram (ECG) signal has a low frequency and a weak amplitude, it is sensitive to miscellaneous mixed noises, which may reduce the diagnostic accuracy and hinder the physician's correct decision on patients. The dual tree wavelet transform (DT-WT) is one of the most recent enhanced versions of discrete wavelet transform. However, threshold tuning on this method for noise removal from ECG signal has not been investigated yet. In this work, we shall provide a comprehensive study on the impact of the choice of threshold algorithm, threshold value, and the appropriate wavelet decomposition level to evaluate the ECG signal de-noising performance. A set of simulations is performed on both synthetic and real ECG signals to achieve the promised results. First, the synthetic ECG signal is used to observe the algorithm response. The evaluation results of synthetic ECG signal corrupted by various types of noise has showed that the modified unified threshold and wavelet hyperbolic threshold de-noising method is better in realistic and colored noises. The tuned threshold is then used on real ECG signals from the MIT-BIH database. The results has shown that the proposed method achieves higher performance than the ordinary dual tree wavelet transform into all kinds of noise removal from ECG signal. The simulation results indicate that the algorithm is robust for all kinds of noises with varying degrees of input noise, providing a high quality clean signal. Moreover, the algorithm is quite simple and can be used in real time ECG monitoring.

Node Query Preservation for Deterministic Linear Top-Down Tree Transducers

Directory of Open Access Journals (Sweden)

Kazuki Miyahara

2013-11-01

Full Text Available This paper discusses the decidability of node query preservation problems for XML document transformations. We assume a transformation given by a deterministic linear top-down data tree transducer (abbreviated as DLT^V and an n-ary query based on runs of a tree automaton. We say that a DLT^V Tr strongly preserves a query Q if there is a query Q' such that for every document t, the answer set of Q' for Tr(t is equal to the answer set of Q for t. Also we say that Tr weakly preserves Q if there is a query Q' such that for every t_d in the range of Tr, the answer set of Q' for t_d is equal to the union of the answer set of Q for t such that t_d = Tr(t. We show that the weak preservation problem is coNP-complete and the strong preservation problem is in 2-EXPTIME.

External Data Structures for Shortest Path Queries on Planar Digraphs

DEFF Research Database (Denmark)

Arge, Lars; Toma, Laura

2005-01-01

In this paper we present space-query trade-offs for external memory data structures that answer shortest path queries on planar directed graphs. For any S = Ω(N 1 + ε) and S = O(N2/B), our main result is a family of structures that use S space and answer queries in O(N2/ S B) I/Os, thus obtaining...... optimal space-query product O(N2/B). An S space structure can be constructed in O(√S · sort(N)) I/Os, where sort(N) is the number of I/Os needed to sort N elements, B is the disk block size, and N is the size of the graph....

Minimizing I/O Costs of Multi-Dimensional Queries with BitmapIndices

Energy Technology Data Exchange (ETDEWEB)

Rotem, Doron; Stockinger, Kurt; Wu, Kesheng

2006-03-30

Bitmap indices have been widely used in scientific applications and commercial systems for processing complex,multi-dimensional queries where traditional tree-based indices would not work efficiently. A common approach for reducing the size of a bitmap index for high cardinality attributes is to group ranges of values of an attribute into bins and then build a bitmap for each bin rather than a bitmap for each value of the attribute. Binning reduces storage costs,however, results of queries based on bins often require additional filtering for discarding it false positives, i.e., records in the result that do not satisfy the query constraints. This additional filtering,also known as ''candidate checking,'' requires access to the base data on disk and involves significant I/O costs. This paper studies strategies for minimizing the I/O costs for ''candidate checking'' for multi-dimensional queries. This is done by determining the number of bins allocated for each dimension and then placing bin boundaries in optimal locations. Our algorithms use knowledge of data distribution and query workload. We derive several analytical results concerning optimal bin allocation for a probabilistic query model. Our experimental evaluation with real life data shows an average I/O cost improvement of at least a factor of 10 for multi-dimensional queries on datasets from two different applications. Our experiments also indicate that the speedup increases with the number of query dimensions.

Video Stream Retrieval of Unseen Queries using Semantic Memory

NARCIS (Netherlands)

Cappallo, S.; Mensink, T.; Snoek, C.G.M.; Wilson, R.C.; Hancock, E.R.; Smith, W.A.P.

2016-01-01

Retrieval of live, user-broadcast video streams is an under-addressed and increasingly relevant challenge. The on-line nature of the problem requires temporal evaluation and the unforeseeable scope of potential queries motivates an approach which can accommodate arbitrary search queries. To account

Efficient and Flexible KNN Query Processing in Real-Life Road Networks

DEFF Research Database (Denmark)

Lu, Yang; Bui, Bin; Zhao, Jiakui

2008-01-01

are included into the RNG index, which enables the index to support both distance-based and time-based KNN queries and continuous KNN queries. Our work extends previous ones by taking into account more practical scenarios, such as complexities in real-life road networks and time-based KNN queries. Extensive......Along with the developments of mobile services, effectively modeling road networks and efficiently indexing and querying network constrained objects has become a challenging problem. In this paper, we first introduce a road network model which captures real-life road networks better than previous...

Searchable Data Vault: Encrypted Queries in Secure Distributed Cloud Storage

Directory of Open Access Journals (Sweden)

Geong Sen Poh

2017-05-01

Full Text Available Cloud storage services allow users to efficiently outsource their documents anytime and anywhere. Such convenience, however, leads to privacy concerns. While storage providers may not read users’ documents, attackers may possibly gain access by exploiting vulnerabilities in the storage system. Documents may also be leaked by curious administrators. A simple solution is for the user to encrypt all documents before submitting them. This method, however, makes it impossible to efficiently search for documents as they are all encrypted. To resolve this problem, we propose a multi-server searchable symmetric encryption (SSE scheme and construct a system called the searchable data vault (SDV. A unique feature of the scheme is that it allows an encrypted document to be divided into blocks and distributed to different storage servers so that no single storage provider has a complete document. By incorporating the scheme, the SDV protects the privacy of documents while allowing for efficient private queries. It utilizes a web interface and a controller that manages user credentials, query indexes and submission of encrypted documents to cloud storage services. It is also the first system that enables a user to simultaneously outsource and privately query documents from a few cloud storage services. Our preliminary performance evaluation shows that this feature introduces acceptable computation overheads when compared to submitting documents directly to a cloud storage service.

Two Dimensional Range Minimum Queries and Fibonacci Lattices

DEFF Research Database (Denmark)

Brodal, Gerth Stølting; Davoodi, Pooya; Lewenstein, Moshe

2012-01-01

technique—the discrepancy properties of Fibonacci lattices—we give an indexing data structure for 2D-RMQs that uses O(N/c) bits additional space with O(clogc(loglogc)2) query time, for any parameter c, 4 ≤ c ≤ N. Also, when the entries of the input matrix are from {0,1}, we show that the query time can...

Can Internet search queries help to predict stock market volatility?

OpenAIRE

Dimpfl, Thomas; Jank, Stephan

2011-01-01

This paper studies the dynamics of stock market volatility and retail investor attention measured by internet search queries. We find a strong co-movement of stock market indices’ realized volatility and the search queries for their names. Furthermore, Granger causality is bi-directional: high searches follow high volatility, and high volatility follows high searches. Using the latter feedback effect to predict volatility we find that search queries contain additional information about market...

Development and empirical user-centered evaluation of semantically-based query recommendation for an electronic health record search engine.

Science.gov (United States)

Hanauer, David A; Wu, Danny T Y; Yang, Lei; Mei, Qiaozhu; Murkowski-Steffy, Katherine B; Vydiswaran, V G Vinod; Zheng, Kai

2017-03-01

The utility of biomedical information retrieval environments can be severely limited when users lack expertise in constructing effective search queries. To address this issue, we developed a computer-based query recommendation algorithm that suggests semantically interchangeable terms based on an initial user-entered query. In this study, we assessed the value of this approach, which has broad applicability in biomedical information retrieval, by demonstrating its application as part of a search engine that facilitates retrieval of information from electronic health records (EHRs). The query recommendation algorithm utilizes MetaMap to identify medical concepts from search queries and indexed EHR documents. Synonym variants from UMLS are used to expand the concepts along with a synonym set curated from historical EHR search logs. The empirical study involved 33 clinicians and staff who evaluated the system through a set of simulated EHR search tasks. User acceptance was assessed using the widely used technology acceptance model. The search engine's performance was rated consistently higher with the query recommendation feature turned on vs. off. The relevance of computer-recommended search terms was also rated high, and in most cases the participants had not thought of these terms on their own. The questions on perceived usefulness and perceived ease of use received overwhelmingly positive responses. A vast majority of the participants wanted the query recommendation feature to be available to assist in their day-to-day EHR search tasks. Challenges persist for users to construct effective search queries when retrieving information from biomedical documents including those from EHRs. This study demonstrates that semantically-based query recommendation is a viable solution to addressing this challenge. Published by Elsevier Inc.

A precision study of the fine tuning in the DiracNMSSM

International Nuclear Information System (INIS)

Kaminska, Anna; Ross, Graham G.; Staub, Florian; Bonn Univ.

2014-01-01

Recently the DiracNMSSM has been proposed as a possible solution to reduce the fine tuning in supersymmetry. We determine the degree of fine tuning needed in the DiracNMSSM with and without non-universal gaugino masses and compare it with the fine tuning in the GNMSSM. To apply reasonable cuts on the allowed parameter regions we perform a precise calculation of the Higgs mass. In addition, we include the limits from direct SUSY searches and dark matter abundance. We find that both models are comparable in terms of fine tuning, with the minimal fine tuning in the GNMSSM slightly smaller.

On the Suitability of Skyline Queries for Data Exploration

DEFF Research Database (Denmark)

Chester, Sean; Mortensen, Michael Lind; Assent, Ira

2014-01-01

The skyline operator has been studied in database research for multi-criteria decision making. Until now the focus has been on the efficiency or accuracy of single queries. In practice, however, users are increasingly confronted with unknown data collections, where precise query formulation proves...

The value of Retrospective and Concurrent Think Aloud in formative usability testing of a physician data query tool.

Science.gov (United States)

Peute, Linda W P; de Keizer, Nicolette F; Jaspers, Monique W M

2015-06-01

To compare the performance of the Concurrent (CTA) and Retrospective (RTA) Think Aloud method and to assess their value in a formative usability evaluation of an Intensive Care Registry-physician data query tool designed to support ICU quality improvement processes. Sixteen representative intensive care physicians participated in the usability evaluation study. Subjects were allocated to either the CTA or RTA method by a matched randomized design. Each subject performed six usability-testing tasks of varying complexity in the query tool in a real-working context. Methods were compared with regard to number and type of problems detected. Verbal protocols of CTA and RTA were analyzed in depth to assess differences in verbal output. Standardized measures were applied to assess thoroughness in usability problem detection weighted per problem severity level and method overall effectiveness in detecting usability problems with regard to the time subjects spent per method. The usability evaluation of the data query tool revealed a total of 43 unique usability problems that the intensive care physicians encountered. CTA detected unique usability problems with regard to graphics/symbols, navigation issues, error messages, and the organization of information on the query tool's screens. RTA detected unique issues concerning system match with subjects' language and applied terminology. The in-depth verbal protocol analysis of CTA provided information on intensive care physicians' query design strategies. Overall, CTA performed significantly better than RTA in detecting usability problems. CTA usability problem detection effectiveness was 0.80 vs. 0.62 (pusability problems of a moderate (0.85 vs. 0.7) and severe nature (0.71 vs. 0.57). In this study, the CTA is more effective in usability-problem detection and provided clarification of intensive care physician query design strategies to inform redesign of the query tool. However, CTA does not outperform RTA. The RTA

Intelligent query processing for semantic mediation of information systems

Directory of Open Access Journals (Sweden)

Saber Benharzallah

2011-11-01

Full Text Available We propose an intelligent and an efficient query processing approach for semantic mediation of information systems. We propose also a generic multi agent architecture that supports our approach. Our approach focuses on the exploitation of intelligent agents for query reformulation and the use of a new technology for the semantic representation. The algorithm is self-adapted to the changes of the environment, offers a wide aptitude and solves the various data conflicts in a dynamic way; it also reformulates the query using the schema mediation method for the discovered systems and the context mediation for the other systems.

Relaxing rdf queries based on user and domain preferences

DEFF Research Database (Denmark)

Dolog, Peter; Stueckenschmidt, Heiner; Wache, Holger

2009-01-01

Research in cooperative query answering is triggered by the observation that users are often not able to correctly formulate queries to databases such that they return the intended result. Due to lacking knowledge about the contents and the structure of a database, users will often only be able t...... application in the context of e-learning systems....... knowledge and user preferences. We describe a framework for information access that combines query refinement and relaxation in order to provide robust, personalized access to heterogeneous resource description framework data as well as an implementation in terms of rewriting rules and explain its...

Performance Tuning of Fock Matrix and Two-Electron Integral Calculations for NWChem on Leading HPC Platforms

Energy Technology Data Exchange (ETDEWEB)

Shan, Hongzhan; Austin, Brian M.; De Jong, Wibe A.; Oliker, Leonid; Wright, Nicholas J.; Apra, Edoardo

2014-10-01

Attaining performance in the evaluation of two-electron repulsion integrals and constructing the Fock matrix is of considerable importance to the computational chemistry community. Due to its numerical complexity improving the performance behavior across a variety of leading supercomputing platforms is an increasing challenge due to the significant diversity in high-performance computing architectures. In this paper, we present our successful tuning methodology for these important numerical methods on the Cray XE6, the Cray XC30, the IBM BG/Q, as well as the Intel Xeon Phi. Our optimization schemes leverage key architectural features including vectorization and simultaneous multithreading, and results in speedups of up to 2.5x compared with the original implementation.

Blink and it's done: Interactive queries on very large data

OpenAIRE

Agarwal, Sameer; Iyer, Anand P.; Panda, Aurojit; Mozafari, Barzan; Stoica, Ion; Madden, Samuel R.

2012-01-01

In this demonstration, we present BlinkDB, a massively parallel, sampling-based approximate query processing framework for running interactive queries on large volumes of data. The key observation in BlinkDB is that one can make reasonable decisions in the absence of perfect answers. BlinkDB extends the Hive/HDFS stack and can handle the same set of SPJA (selection, projection, join and aggregate) queries as supported by these systems. BlinkDB provides real-time answers along with statistical...

Query-dependent banding (QDB for faster RNA similarity searches.

Directory of Open Access Journals (Sweden)

Eric P Nawrocki

2007-03-01

Full Text Available When searching sequence databases for RNAs, it is desirable to score both primary sequence and RNA secondary structure similarity. Covariance models (CMs are probabilistic models well-suited for RNA similarity search applications. However, the computational complexity of CM dynamic programming alignment algorithms has limited their practical application. Here we describe an acceleration method called query-dependent banding (QDB, which uses the probabilistic query CM to precalculate regions of the dynamic programming lattice that have negligible probability, independently of the target database. We have implemented QDB in the freely available Infernal software package. QDB reduces the average case time complexity of CM alignment from LN(2.4 to LN(1.3 for a query RNA of N residues and a target database of L residues, resulting in a 4-fold speedup for typical RNA queries. Combined with other improvements to Infernal, including informative mixture Dirichlet priors on model parameters, benchmarks also show increased sensitivity and specificity resulting from improved parameterization.

Robust Optimization of Database Queries

Indian Academy of Sciences (India)

JAYANT

2011-07-06

Jul 6, 2011 ... Based on first-order logic. ○ Edgar ... Cost-based Query Optimizer s choice of execution plan ... Determines the values of goods shipped between nations in a time period select ..... Born: 1881 Elected: 1934 Section: Medicine.

Fuzzy Querying: Issues and Perspectives..

Czech Academy of Sciences Publication Activity Database

Kacprzyk, J.; Pasi, G.; Vojtáš, Peter; Zadrozny, S.

2000-01-01

Roč. 36, č. 6 (2000), s. 605-616 ISSN 0023-5954 Institutional research plan: AV0Z1030915 Keywords : flexible querying * information retrieval * fuzzy databases Subject RIV: BA - General Mathematics http://dml.cz/handle/10338.dmlcz/135376

Using Bitmap Indexing Technology for Combined Numerical and TextQueries

Energy Technology Data Exchange (ETDEWEB)

Stockinger, Kurt; Cieslewicz, John; Wu, Kesheng; Rotem, Doron; Shoshani, Arie

2006-10-16

In this paper, we describe a strategy of using compressedbitmap indices to speed up queries on both numerical data and textdocuments. By using an efficient compression algorithm, these compressedbitmap indices are compact even for indices with millions of distinctterms. Moreover, bitmap indices can be used very efficiently to answerBoolean queries over text documents involving multiple query terms.Existing inverted indices for text searches are usually inefficient forcorpora with a very large number of terms as well as for queriesinvolving a large number of hits. We demonstrate that our compressedbitmap index technology overcomes both of those short-comings. In aperformance comparison against a commonly used database system, ourindices answer queries 30 times faster on average. To provide full SQLsupport, we integrated our indexing software, called FastBit, withMonetDB. The integrated system MonetDB/FastBit provides not onlyefficient searches on a single table as FastBit does, but also answersjoin queries efficiently. Furthermore, MonetDB/FastBit also provides avery efficient retrieval mechanism of result records.

Proportional–Integral–Derivative (PID Controller Tuning using Particle Swarm Optimization Algorithm

Directory of Open Access Journals (Sweden)

J. S. Bassi

2012-08-01

Full Text Available The proportional-integral-derivative (PID controllers are the most popular controllers used in industry because of their remarkable effectiveness, simplicity of implementation and broad applicability. However, manual tuning of these controllers is time consuming, tedious and generally lead to poor performance. This tuning which is application specific also deteriorates with time as a result of plant parameter changes. This paper presents an artificial intelligence (AI method of particle swarm optimization (PSO algorithm for tuning the optimal proportional-integral derivative (PID controller parameters for industrial processes. This approach has superior features, including easy implementation, stable convergence characteristic and good computational efficiency over the conventional methods. Ziegler- Nichols, tuning method was applied in the PID tuning and results were compared with the PSO-Based PID for optimum control. Simulation results are presented to show that the PSO-Based optimized PID controller is capable of providing an improved closed-loop performance over the Ziegler- Nichols tuned PID controller Parameters. Compared to the heuristic PID tuning method of Ziegler-Nichols, the proposed method was more efficient in improving the step response characteristics such as, reducing the steady-states error; rise time, settling time and maximum overshoot in speed control of DC motor.

Heavy vehicle pitch dynamics and suspension tuning

OpenAIRE

Cao, Dongpu; Rakheja, Subhash; Su, Chun-Yi

2008-01-01

The influence of suspension tuning of passenger cars on bounce and pitch ride performance has been explored in a number of studies, while only minimal efforts have been made for establishing similar rules for heavy vehicles. This study aims to explore pitch dynamics and suspension tunings of a two-axle heavy vehicle with unconnected suspension, which could also provide valuable information for heavy vehicles with coupled suspensions. Based on a generalised pitch-plane model of a two-axle heav...

PERI - Auto-tuning Memory Intensive Kernels for Multicore

Energy Technology Data Exchange (ETDEWEB)

Bailey, David H; Williams, Samuel; Datta, Kaushik; Carter, Jonathan; Oliker, Leonid; Shalf, John; Yelick, Katherine; Bailey, David H

2008-06-24

We present an auto-tuning approach to optimize application performance on emerging multicore architectures. The methodology extends the idea of search-based performance optimizations, popular in linear algebra and FFT libraries, to application-specific computational kernels. Our work applies this strategy to Sparse Matrix Vector Multiplication (SpMV), the explicit heat equation PDE on a regular grid (Stencil), and a lattice Boltzmann application (LBMHD). We explore one of the broadest sets of multicore architectures in the HPC literature, including the Intel Xeon Clovertown, AMD Opteron Barcelona, Sun Victoria Falls, and the Sony-Toshiba-IBM (STI) Cell. Rather than hand-tuning each kernel for each system, we develop a code generator for each kernel that allows us to identify a highly optimized version for each platform, while amortizing the human programming effort. Results show that our auto-tuned kernel applications often achieve a better than 4X improvement compared with the original code. Additionally, we analyze a Roofline performance model for each platform to reveal hardware bottlenecks and software challenges for future multicore systems and applications.

A new weighted fuzzy grammar on object oriented database queries

Directory of Open Access Journals (Sweden)

Ali Haroonabadi

2012-08-01

Full Text Available The fuzzy object oriented database model is often used to handle the existing imprecise and complicated objects for many real-world applications. The main focus of this paper is on fuzzy queries and tries to analyze a complicated and complex query to get more meaningful and closer responses. The method permits the user to provide the possibility of allocating the weight to various parts of the query, which makes it easier to follow better goals and return the target objects.

Software and DVFS Tuning for Performance and Energy-Efficiency on Intel KNL Processors

Directory of Open Access Journals (Sweden)

Enrico Calore

2018-06-01

Full Text Available Energy consumption of processors and memories is quickly becoming a limiting factor in the deployment of large computing systems. For this reason, it is important to understand the energy performance of these processors and to study strategies allowing their use in the most efficient way. In this work, we focus on the computing and energy performance of the Knights Landing Xeon Phi, the latest Intel many-core architecture processor for HPC applications. We consider the 64-core Xeon Phi 7230 and profile its performance and energy efficiency using both its on-chip MCDRAM and the off-chip DDR4 memory as the main storage for application data. As a benchmark application, we use a lattice Boltzmann code heavily optimized for this architecture and implemented using several different arrangements of the application data in memory (data-layouts, in short. We also assess the dependence of energy consumption on data-layouts, memory configurations (DDR4 or MCDRAM and the number of threads per core. We finally consider possible trade-offs between computing performance and energy efficiency, tuning the clock frequency of the processor using the Dynamic Voltage and Frequency Scaling (DVFS technique.

A few examples go a long way: Constructing query models from elaborate query formulations

NARCIS (Netherlands)

Balog, K.; Weerkamp, W.; de Rijke, M.; Myaeng, S.-H.; Oard, D.W.; Sebastiani, F.; Chua, T.-S.; Leong, M.-K.

2008-01-01

We address a specific enterprise document search scenario, where the information need is expressed in an elaborate manner. In our scenario, information needs are expressed using a short query (of a few keywords) together with examples of key reference pages. Given this setup, we investigate how the

An XML-Enabled Data Mining Query Language XML-DMQL

NARCIS (Netherlands)

Feng, L.; Dillon, T.

2005-01-01

Inspired by the good work of Han et al. (1996) and Elfeky et al. (2001) on the design of data mining query languages for relational and object-oriented databases, in this paper, we develop an expressive XML-enabled data mining query language by extension of XQuery. We first describe some

Study of Query Expansion Techniques and Their Application in the Biomedical Information Retrieval

Directory of Open Access Journals (Sweden)

A. R. Rivas

2014-01-01

retrieval systems. These techniques help to overcome vocabulary mismatch issues by expanding the original query with additional relevant terms and reweighting the terms in the expanded query. In this paper, different text preprocessing and query expansion approaches are combined to improve the documents initially retrieved by a query in a scientific documental database. A corpus belonging to MEDLINE, called Cystic Fibrosis, is used as a knowledge source. Experimental results show that the proposed combinations of techniques greatly enhance the efficiency obtained by traditional queries.

Implementing and evaluating a regional strategy to improve testing rates in VA patients at risk for HIV, utilizing the QUERI process as a guiding framework: QUERI Series.

Science.gov (United States)

Goetz, Matthew B; Bowman, Candice; Hoang, Tuyen; Anaya, Henry; Osborn, Teresa; Gifford, Allen L; Asch, Steven M

2008-03-19

We describe how we used the framework of the U.S. Department of Veterans Affairs (VA) Quality Enhancement Research Initiative (QUERI) to develop a program to improve rates of diagnostic testing for the Human Immunodeficiency Virus (HIV). This venture was prompted by the observation by the CDC that 25% of HIV-infected patients do not know their diagnosis - a point of substantial importance to the VA, which is the largest provider of HIV care in the United States. Following the QUERI steps (or process), we evaluated: 1) whether undiagnosed HIV infection is a high-risk, high-volume clinical issue within the VA, 2) whether there are evidence-based recommendations for HIV testing, 3) whether there are gaps in the performance of VA HIV testing, and 4) the barriers and facilitators to improving current practice in the VA.Based on our findings, we developed and initiated a QUERI step 4/phase 1 pilot project using the precepts of the Chronic Care Model. Our improvement strategy relies upon electronic clinical reminders to provide decision support; audit/feedback as a clinical information system, and appropriate changes in delivery system design. These activities are complemented by academic detailing and social marketing interventions to achieve provider activation. Our preliminary formative evaluation indicates the need to ensure leadership and team buy-in, address facility-specific barriers, refine the reminder, and address factors that contribute to inter-clinic variances in HIV testing rates. Preliminary unadjusted data from the first seven months of our program show 3-5 fold increases in the proportion of at-risk patients who are offered HIV testing at the VA sites (stations) where the pilot project has been undertaken; no change was seen at control stations. This project demonstrates the early success of the application of the QUERI process to the development of a program to improve HIV testing rates. Preliminary unadjusted results show that the coordinated use of

Performance and complexity of tunable sparse network coding with gradual growing tuning functions over wireless networks

OpenAIRE

Garrido Ortiz, Pablo; Sørensen, Chres W.; Lucani Roetter, Daniel Enrique; Agüero Calvo, Ramón

2016-01-01

Random Linear Network Coding (RLNC) has been shown to be a technique with several benefits, in particular when applied over wireless mesh networks, since it provides robustness against packet losses. On the other hand, Tunable Sparse Network Coding (TSNC) is a promising concept, which leverages a trade-off between computational complexity and goodput. An optimal density tuning function has not been found yet, due to the lack of a closed-form expression that links density, performance and comp...

PID motion control tuning rules in a damping injection framework

NARCIS (Netherlands)

Tadele, T.S.; de Vries, Theodorus J.A.; Stramigioli, Stefano

2013-01-01

This paper presents a general design approach for a performance based tuning of a damping injection framework impedance controller by using insights from PID motion control tuning rules. The damping injection framework impedance controller is suitable for human friendly robots as it enhances safety

References and arrow notation instead of join operation in query languages

Directory of Open Access Journals (Sweden)

Alexandr Savinov

2012-10-01

Full Text Available We study properties of the join operation in query languages and describe some of its major drawbacks. We provide strong arguments against using joins as a main construct for retrieving related data elements in general purpose query languages and argue for using references instead. Since conventional references are quite restrictive when applied to data modeling and query languages, we propose to use generalized references as they are defined in the concept-oriented model (COM. These references are used by two new operations, called projection and de-projection, which are denoted by right and left arrows and therefore this access method is referred to as arrow notation. We demonstrate advantages of the arrow notation in comparison to joins and argue that it makes queries simpler, more natural, easier to understand, and the whole query writing process more productive and less error-prone.

Self tuning fuzzy PID type load and frequency controller

International Nuclear Information System (INIS)

Yesil, E.; Guezelkaya, M.; Eksin, I.

2004-01-01

In this paper, a self tuning fuzzy PID type controller is proposed for solving the load frequency control (LFC) problem. The fuzzy PID type controller is constructed as a set of control rules, and the control signal is directly deduced from the knowledge base and the fuzzy inference. Moreover, there exists a self tuning mechanism that adjusts the input scaling factor corresponding to the derivative coefficient and the output scaling factor corresponding to the integral coefficient of the PID type fuzzy logic controller in an on-line manner. The self tuning mechanism depends on the peak observer idea, and this idea is modified and adapted to the LFC problem. A two area interconnected system is assumed for demonstrations. The proposed self tuning fuzzy PID type controller has been compared with the fuzzy PID type controller without a self tuning mechanism and the conventional integral controller through some performance indices

Special Issue on Automatic Application Tuning for HPC Architectures

Directory of Open Access Journals (Sweden)

Siegfried Benkner

2014-01-01

Full Text Available High Performance Computing architectures have become incredibly complex and exploiting their full potential is becoming more and more challenging. As a consequence, automatic performance tuning (autotuning of HPC applications is of growing interest and many research groups around the world are currently involved. Autotuning is still a rapidly evolving research field with many different approaches being taken. This special issue features selected papers presented at the Dagstuhl seminar on “Automatic Application Tuning for HPC Architectures” in October 2013, which brought together researchers from the areas of autotuning and performance analysis in order to exchange ideas and steer future collaborations.

Sharing-Aware Horizontal Partitioning for Exploiting Correlations during Query Processing

DEFF Research Database (Denmark)

Tzoumas, Kostas; Deshpande, Amol; Jensen, Christian Søndergaard

2010-01-01

Optimization of join queries based on average selectivities is suboptimal in highly correlated databases. In such databases, relations are naturally divided into partitions, each partition having substantially different statistical characteristics. It is very compelling to discover such data...... partitions during query optimization and create multiple plans for a given query, one plan being optimal for a particular combination of data partitions. This scenario calls for the sharing of state among plans, so that common intermediate results are not recomputed. We study this problem in a setting...

Processing Incomplete Query Specifications in a Context-Dependent Reasoning Framework

Directory of Open Access Journals (Sweden)

Neli P. Zlatareva

2013-04-01

Full Text Available Search is the most prominent web service, which is about to change dramatically with the transition to the Semantic Web. Semantic Web applications are expected to deal with complex conjunctive queries, and not always such queries can be completely and precisely defined. Current Semantic Web reasoners built upon Description Logics have limited processing power in such environments. We discuss some of their limitations, and show how an alternative logical framework utilizing context-dependent rules can be extended to handle incomplete or imprecise query specifications.

A Typed Text Retrieval Query Language for XML Documents.

Science.gov (United States)

Colazzo, Dario; Sartiani, Carlo; Albano, Antonio; Manghi, Paolo; Ghelli, Giorgio; Lini, Luca; Paoli, Michele

2002-01-01

Discussion of XML focuses on a description of Tequyla-TX, a typed text retrieval query language for XML documents that can search on both content and structures. Highlights include motivations; numerous examples; word-based and char-based searches; tag-dependent full-text searches; text normalization; query algebra; data models and term language;…

A Distributed Approach to Continuous Monitoring of Constrained k-Nearest Neighbor Queries in Road Networks

Directory of Open Access Journals (Sweden)

Hyung-Ju Cho

2012-01-01

Full Text Available Given two positive parameters k and r, a constrained k-nearest neighbor (CkNN query returns the k closest objects within a network distance r of the query location in road networks. In terms of the scalability of monitoring these CkNN queries, existing solutions based on central processing at a server suffer from a sudden and sharp rise in server load as well as messaging cost as the number of queries increases. In this paper, we propose a distributed and scalable scheme called DAEMON for the continuous monitoring of CkNN queries in road networks. Our query processing is distributed among clients (query objects and server. Specifically, the server evaluates CkNN queries issued at intersections of road segments, retrieves the objects on the road segments between neighboring intersections, and sends responses to the query objects. Finally, each client makes its own query result using this server response. As a result, our distributed scheme achieves close-to-optimal communication costs and scales well to large numbers of monitoring queries. Exhaustive experimental results demonstrate that our scheme substantially outperforms its competitor in terms of query processing time and messaging cost.

Query Processing and Interlinking of Fuzzy Object-Oriented Database

OpenAIRE

Shweta Dwivedi; Santosh Kumar

2017-01-01

Due to the many limitation and poor data handling in the existing relational database, the software professional and researchers moves towards the object-oriented database which has much better capability to handling the real and complex real world data i.e. clear and crisp data and also have the capability to perform some huge and complex queries in an effective manner. On the other hand, a new approach in database is introduced named as Fuzzy Object-Oriented Database (FOOD); it has all the ...

PSO algorithm enhanced with Lozi Chaotic Map - Tuning experiment

Energy Technology Data Exchange (ETDEWEB)

Pluhacek, Michal; Senkerik, Roman; Zelinka, Ivan [Tomas Bata University in Zlín, Faculty of Applied Informatics Department of Informatics and Artificial Intelligence nám. T.G. Masaryka 5555, 760 01 Zlín (Czech Republic)

2015-03-10

In this paper it is investigated the effect of tuning of control parameters of the Lozi Chaotic Map employed as a chaotic pseudo-random number generator for the particle swarm optimization algorithm. Three different benchmark functions are selected from the IEEE CEC 2013 competition benchmark set. The Lozi map is extensively tuned and the performance of PSO is evaluated.

PSO algorithm enhanced with Lozi Chaotic Map - Tuning experiment

International Nuclear Information System (INIS)

Pluhacek, Michal; Senkerik, Roman; Zelinka, Ivan

2015-01-01

In this paper it is investigated the effect of tuning of control parameters of the Lozi Chaotic Map employed as a chaotic pseudo-random number generator for the particle swarm optimization algorithm. Three different benchmark functions are selected from the IEEE CEC 2013 competition benchmark set. The Lozi map is extensively tuned and the performance of PSO is evaluated

Application of digital beam position processor Libera on tune measurement

International Nuclear Information System (INIS)

Zhang Chunhui; Sun Baogen; Cao Yong; Lu Ping; Li Jihao

2006-01-01

Digital signal processing (DSP) is widely used in the field of beam diagnostics. Especially, DSP achieves very good performance in beam position signal analysis and betatron tune measurement. In Hefei light source, when beam was excited by narrow-band Gaussian white nose, Libera, a digital beam position processor, was used to process the signals from beam position monitor (BPM), which contained betatron oscillation. Fast Fourier transform (FFT) was applied to finding out betatron resonance frequency, from which the decimal part of betatron oscillation tune was calculated. By this means, the measure of horizontal tune was 3.5352 and the measure of vertical tune is 2.6299. (authors)

Iterative Controller Tuning for Process with Fold Bifurcations

DEFF Research Database (Denmark)

Huusom, Jakob Kjøbsted; Poulsen, Niels Kjølstad; Jørgensen, Sten Bay

2007-01-01

Processes involving fold bifurcation are notoriously difficult to control in the vicinity of the fold where most often optimal productivity is achieved . In cases with limited process insight a model based control synthesis is not possible. This paper uses a data driven approach with an improved...... version of iterative feedback tuning to optimizing a closed loop performance criterion, as a systematic tool for tuning process with fold bifurcations....

Self-tuning Torque Control of Induction Motors for High Performance Applications

DEFF Research Database (Denmark)

Rasmussen, Henrik

-link voltage a non-linear model of the inverter giving the relation between turn-on times and voltages is developed. A dynamic model of the induction motor based on space phasors is described. The model in a reference frame fixed to the rotor magnetizing current is analyzed in detail and extended with a model......: · To analyze and develop strategies for torque control of induction motors well suited for automatic tuning. · To analyze and develop methods for automatic tuning of the applied controllers. · To develop robust methods for adaptive field oriented control. · To test the final concept on different motors...... for magnetic saturating. The parameters in this non-linear model of the motor and inverter are determined by impressing some special designed stator voltage signals and measuring the stator currents. A s something new in this context a robust current controller is determined by relay experiment before starting...

An Approach to Assist Designers With Their Queries and Designs

DEFF Research Database (Denmark)

Ahmed, Saeema

2006-01-01

Recent research investigating how engineers search for information has concluded that engineering designers acquire assistance when formulating queries. An approach to assist designers with their queries is presented. This approach forms part of a knowledge management system, where indexed...... documents are entered into the system (or are automatically indexed by tools within a system). The method builds up a network based upon indices assigned to documents. The network (or chunk) is presented back to the user once a search for knowledge has been completed. The network is build up as indexed...... documents are entered in to a knowledge-based system and is generated dynamically. The network can be used to assist a designer in searching for information; reformulating a query and; to prompt design tasks. This paper presents an approach to prompt designers with their design queries, along with some...

Indexing, Query Processing, and Clustering of Spatio-Temporal Text Objects

DEFF Research Database (Denmark)

Skovsgaard, Anders

With the increasing mobile use of the web from geo-positioned devices, the Internet is increasingly acquiring a spatial aspect, with still more types of content being geo-tagged. As a result of this development, a wide range of location-aware queries and applications have emerged. The large amounts...... of data available coupled with the increasing number of location-aware queries calls for efficient indexing and query processing techniques. This dissertation investigates how to manage geo-tagged text content to support these workloads in three specific areas: (i) grouping of spatio-textual objects, (ii......, the grouping of spatio-textual objects is done without considering query locations, and a clustering approach is proposed that takes into account both the spatial and textual attributes of the objects. The technique expands clusters based on a proposed quality function that enables clusters of arbitrary shape...

Advanced hybrid query tree algorithm based on slotted backoff mechanism in RFID

Directory of Open Access Journals (Sweden)

XIE Xiaohui

2013-12-01

Full Text Available The merits of performance quality for a RFID system are determined by the effectiveness of tag anti-collision algorithm.Many algorithms for RFID system of tag identification have been proposed,but they all have obvious weaknesses,such as slow speed of identification,unstable and so on.The existing algorithms can be divided into two groups,one is based on ALOHA and another is based on query tree.This article is based on the hybrid query tree algorithm,combined with a slotted backoff mechanism and a specific encoding (Manchester encoding.The number of value“1” in every three consecutive bits of tags is used to determine the tag response time slots,which will greatly reduce the time slot of the collision and improve the recognition efficiency.

Four queries concerning the metaphysics of early human embryogenesis.

Science.gov (United States)

Howsepian, A A

2008-04-01

In this essay, I attempt to provide answers to the following four queries concerning the metaphysics of early human embryogenesis. (1) Following its first cellular fission, is it coherent to claim that one and only one of two "blastomeric" twins of a human zygote is identical with that zygote? (2) Following the fusion of two human pre-embryos, is it coherent to claim that one and only one pre-fusion pre-embryo is identical with that postfusion pre-embryo? (3) Does a live human being come into existence only when its brain comes into existence? (4) At implantation, does a pre-embryo become a mere part of its mother? I argue that either if things have quidditative properties or if criterialism is false, then queries (1) and (2) can be answered in the affirmative; that in light of recent developments in theories of human death and in light of a more "functional" theory of brains, query (3) can be answered in the negative; and that plausible mereological principles require a negative answer to query (4).

QuerySpaces on Hadoop for the ATLAS EventIndex

CERN Document Server

Hrivnac, Julius; The ATLAS collaboration; Cranshaw, Jack; Favareto, Andrea; Prokoshin, Fedor; Glasman, Claudia; Toebbicke, Rainer

2015-01-01

A Hadoop-based implementation of the adaptive query engine serving as the back-end for the ATLAS EventIndex. The QuerySpaces implementation handles both original data and search results providing fast and efficient mechanisms for new user queries using already accumulated knowledge for optimization. Detailed descriptions and statistics about user requests are collected in HBase tables and HDFS files. Requests are associated to their results and a graph of relations between them is created to be used to find the most efficient way of providing answers to new requests The environment is completely transparent to users and is accessible over several command-line interfaces, a Web Service and a programming API.

Improving the Usability of OCL as an Ad-hoc Model Querying Language

DEFF Research Database (Denmark)

Störrle, Harald

2013-01-01

from our research and make it accessible to the OCL community, we propose the OCL Query API (OQAPI), a library of query-predicates to improve the user-friendliness of OCL for ad-hoc querying. The usability of OQAPI is studied using controlled experiments. We nd considerable evidence to support our...

Architecture of Automated Database Tuning Using SGA Parameters

Directory of Open Access Journals (Sweden)

Hitesh KUMAR SHARMA

2012-05-01

Full Text Available Business Data always growth from kilo byte, mega byte, giga byte, tera byte, peta byte, and so far. There is no way to avoid this increasing rate of data till business still running. Because of this issue, database tuning be critical part of a information system. Tuning a database in a cost-effective manner is a growing challenge. The total cost of ownership (TCO of information technology needs to be significantly reduced by minimizing people costs. In fact, mistakes in operations and administration of information systems are the single most reasons for system outage and unacceptable performance [3]. One way of addressing the challenge of total cost of ownership is by making information systems more self-managing. A particularly difficult piece of the ambitious vision of making database systems self-managing is the automation of database performance tuning. In this paper, we will explain the progress made thus far on this important problem. Specifically, we will propose the architecture and Algorithm for this problem.

Schedule Sales Query Report Generation System

Data.gov (United States)

General Services Administration — Schedule Sales Query presents sales volume figures as reported to GSA by contractors. The reports are generated as quarterly reports for the current year and the...

Query Classification and Study of University Students' Search Trends

Science.gov (United States)

Maabreh, Majdi A.; Al-Kabi, Mohammed N.; Alsmadi, Izzat M.

2012-01-01

Purpose: This study is an attempt to develop an automatic identification method for Arabic web queries and divide them into several query types using data mining. In addition, it seeks to evaluate the impact of the academic environment on using the internet. Design/methodology/approach: The web log files were collected from one of the higher…

ATLAS Monte Carlo tunes for MC09

CERN Document Server

The ATLAS collaboration

2010-01-01

This note describes the ATLAS tunes of underlying event and minimum bias description for the main Monte Carlo generators used in the MC09 production. For the main shower generators, pythia and herwig (with jimmy), the MRST LO* parton distribution functions (PDFs) were used for the first time in ATLAS. Special studies on the performance of these, conceptually new, PDFs for high pt physics processes at LHC energies are presented. In addition, a tune of jimmy for CTEQ6.6 is presented, for use with MC@NLO.

Linked data querying through FCA-based schema indexing

OpenAIRE

Brosius, Dominik; Staab, Steffen

2016-01-01

The effciency of SPARQL query evaluation against Linked Open Data may benefit from schema-based indexing. However, many data items come with incomplete schema information or lack schema descriptions entirely. In this position paper, we outline an approach to an indexing of linked data graphs based on schemata induced through Formal Concept Analysis. We show how to map queries onto RDF graphs based on such derived schema information. We sketch next steps for realizing and optimizing the sugges...

Towards Intelligible Query Processing in Relevance Feedback-Based Image Retrieval Systems

OpenAIRE

Mohammed, Belkhatir

2008-01-01

We have specified within the scope of this paper a framework combining semantics and relational (spatial) characterizations within a coupled architecture in order to address the semantic gap. This framework is instantiated by an operational model based on a sound logic-based formalism, allowing to define a representation for image documents and a matching function to compare index and query structures. We have specified a query framework coupling keyword-based querying with a relevance feedba...

A Modular Design for Geo-Distributed Querying : Work in Progress Report

OpenAIRE

Vasilas , Dimitrios; Shapiro , Marc; King , Bradley

2018-01-01

International audience; Most distributed storage systems provide limited abilities for querying data by attributes other than their primary keys. Supporting efficient search on secondary attributes is challenging as applications pose varying requirements to query processing systems, and no single system design can be suitable for all needs. In this paper, we show how to overcome these challenges in order to extend distributed data stores to support queries on secondary attributes. We propose ...

Automatically Preparing Safe SQL Queries

Science.gov (United States)

Bisht, Prithvi; Sistla, A. Prasad; Venkatakrishnan, V. N.

We present the first sound program source transformation approach for automatically transforming the code of a legacy web application to employ PREPARE statements in place of unsafe SQL queries. Our approach therefore opens the way for eradicating the SQL injection threat vector from legacy web applications.

Efficient Verifiable Range and Closest Point Queries in Zero-Knowledge

Directory of Open Access Journals (Sweden)

Ghosh Esha

2016-10-01

Full Text Available We present an efficient method for answering one-dimensional range and closest-point queries in a verifiable and privacy-preserving manner. We consider a model where a data owner outsources a dataset of key-value pairs to a server, who answers range and closest-point queries issued by a client and provides proofs of the answers. The client verifies the correctness of the answers while learning nothing about the dataset besides the answers to the current and previous queries. Our work yields for the first time a zero-knowledge privacy assurance to authenticated range and closest-point queries. Previous work leaked the size of the dataset and used an inefficient proof protocol. Our construction is based on hierarchical identity-based encryption. We prove its security and analyze its efficiency both theoretically and with experiments on synthetic and real data (Enron email and Boston taxi datasets.

Towards automatic parameter tuning of stream processing systems

KAUST Repository

Bilal, Muhammad

2017-09-27

Optimizing the performance of big-data streaming applications has become a daunting and time-consuming task: parameters may be tuned from a space of hundreds or even thousands of possible configurations. In this paper, we present a framework for automating parameter tuning for stream-processing systems. Our framework supports standard black-box optimization algorithms as well as a novel gray-box optimization algorithm. We demonstrate the multiple benefits of automated parameter tuning in optimizing three benchmark applications in Apache Storm. Our results show that a hill-climbing algorithm that uses a new heuristic sampling approach based on Latin Hypercube provides the best results. Our gray-box algorithm provides comparable results while being two to five times faster.

Advanced Query and Data Mining Capabilities for MaROS

Science.gov (United States)

Wang, Paul; Wallick, Michael N.; Allard, Daniel A.; Gladden, Roy E.; Hy, Franklin H.

2013-01-01

The Mars Relay Operational Service (MaROS) comprises a number of tools to coordinate, plan, and visualize various aspects of the Mars Relay network. These levels include a Web-based user interface, a back-end "ReSTlet" built in Java, and databases that store the data as it is received from the network. As part of MaROS, the innovators have developed and implemented a feature set that operates on several levels of the software architecture. This new feature is an advanced querying capability through either the Web-based user interface, or through a back-end REST interface to access all of the data gathered from the network. This software is not meant to replace the REST interface, but to augment and expand the range of available data. The current REST interface provides specific data that is used by the MaROS Web application to display and visualize the information; however, the returned information from the REST interface has typically been pre-processed to return only a subset of the entire information within the repository, particularly only the information that is of interest to the GUI (graphical user interface). The new, advanced query and data mining capabilities allow users to retrieve the raw data and/or to perform their own data processing. The query language used to access the repository is a restricted subset of the structured query language (SQL) that can be built safely from the Web user interface, or entered as freeform SQL by a user. The results are returned in a CSV (Comma Separated Values) format for easy exporting to third party tools and applications that can be used for data mining or user-defined visualization and interpretation. This is the first time that a service is capable of providing access to all cross-project relay data from a single Web resource. Because MaROS contains the data for a variety of missions from the Mars network, which span both NASA and ESA, the software also establishes an access control list (ACL) on each data record

Fragger: a protein fragment picker for structural queries [version 2; referees: 2 approved

Directory of Open Access Journals (Sweden)

Francois Berenger

2018-04-01

Full Text Available Protein modeling and design activities often require querying the Protein Data Bank (PDB with a structural fragment, possibly containing gaps. For some applications, it is preferable to work on a specific subset of the PDB or with unpublished structures. These requirements, along with specific user needs, motivated the creation of a new software to manage and query 3D protein fragments. Fragger is a protein fragment picker that allows protein fragment databases to be created and queried. All fragment lengths are supported and any set of PDB files can be used to create a database. Fragger can efficiently search a fragment database with a query fragment and a distance threshold. Matching fragments are ranked by distance to the query. The query fragment can have structural gaps and the allowed amino acid sequences matching a query can be constrained via a regular expression of one-letter amino acid codes. Fragger also incorporates a tool to compute the backbone RMSD of one versus many fragments in high throughput. Fragger should be useful for protein design, loop grafting and related structural bioinformatics tasks.

Evolutionary Multiobjective Query Workload Optimization of Cloud Data Warehouses

Science.gov (United States)

Dokeroglu, Tansel; Sert, Seyyit Alper; Cinar, Muhammet Serkan

2014-01-01

With the advent of Cloud databases, query optimizers need to find paretooptimal solutions in terms of response time and monetary cost. Our novel approach minimizes both objectives by deploying alternative virtual resources and query plans making use of the virtual resource elasticity of the Cloud. We propose an exact multiobjective branch-and-bound and a robust multiobjective genetic algorithm for the optimization of distributed data warehouse query workloads on the Cloud. In order to investigate the effectiveness of our approach, we incorporate the devised algorithms into a prototype system. Finally, through several experiments that we have conducted with different workloads and virtual resource configurations, we conclude remarkable findings of alternative deployments as well as the advantages and disadvantages of the multiobjective algorithms we propose. PMID:24892048

An Application of Multivariate Statistical Analysis for Query-Driven Visualization

Energy Technology Data Exchange (ETDEWEB)

Gosink, Luke J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Garth, Christoph [Univ. of California, Davis, CA (United States); Anderson, John C. [Univ. of California, Davis, CA (United States); Bethel, E. Wes [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Joy, Kenneth I. [Univ. of California, Davis, CA (United States)

2011-03-01

Driven by the ability to generate ever-larger, increasingly complex data, there is an urgent need in the scientific community for scalable analysis methods that can rapidly identify salient trends in scientific data. Query-Driven Visualization (QDV) strategies are among the small subset of techniques that can address both large and highly complex datasets. This paper extends the utility of QDV strategies with a statistics-based framework that integrates non-parametric distribution estimation techniques with a new segmentation strategy to visually identify statistically significant trends and features within the solution space of a query. In this framework, query distribution estimates help users to interactively explore their query's solution and visually identify the regions where the combined behavior of constrained variables is most important, statistically, to their inquiry. Our new segmentation strategy extends the distribution estimation analysis by visually conveying the individual importance of each variable to these regions of high statistical significance. We demonstrate the analysis benefits these two strategies provide and show how they may be used to facilitate the refinement of constraints over variables expressed in a user's query. We apply our method to datasets from two different scientific domains to demonstrate its broad applicability.

Performance evaluation of full-scale tuned liquid dampers (TLDs) for vibration control of large wind turbines using real-time hybrid testing

DEFF Research Database (Denmark)

Zhang, Zili; Staino, Andrea; Basu, Biswajit

2016-01-01

Highlights •Performance evaluation of full-scale tuned liquid dampers carried out for wind turbines. •Coupled blade-tower model considered in the numerical sub-structure. •Stochastic turbulence due to rotationally sampled spectra considered. •Effect of damping screens experimentally investigated...