@article {20449, title = {Quantum Capacitance-Limited MoS2 Biosensors Enable Remote Label-Free Enzyme Measurements}, journal = {Nanoscale}, year = {2019}, month = {Jan-01-2019}, issn = {2040-3364}, doi = {10.1039/C9NR03171E}, url = {http://pubs.rsc.org/en/Content/ArticleLanding/2019/NR/C9NR03171Ehttp://pubs.rsc.org/en/content/articlepdf/2019/NR/C9NR03171E}, author = {Le, Son T and Guros, Nicholas B and Bruce, Robert C and Cardone, Antonio and Amin, Niranjana D and Zhang, Siyuan and Klauda, Jeffery and Pant, Harish C and Richter, Curt A and Balijepalli, Arvind} } @article {20369, title = {Quantification of Vibrio parahaemolyticus, Vibrio vulnificus and Vibrio cholerae in French Mediterranean coastal lagoons}, journal = {Research in Microbiology}, volume = {164}, year = {2013}, month = {Jan-10-2013}, pages = {867 - 874}, abstract = {Vibrio parahaemolyticus, Vibrio vulnificus and Vibrio cholerae are human pathogens. Little is known about these Vibrio spp. in the coastal lagoons of France. The purpose of this study was to investigate their incidence in water, shellfish and sediment of three French Mediterranean coastal lagoons using the most probable number-polymerase chain reaction (MPN-PCR). In summer, the total number of V. parahaemolyticus in water, sediment, mussels and clams collected from the three lagoons varied from 1 to >1.1 {\texttimes} 103 MPN/l, 0.09 to 1.1 {\texttimes} 103 MPN/ml, 9 to 210 MPN/g and 1.5 to 2.1 MPN/g, respectively. In winter, all samples except mussels contained V. parahaemolyticus, but at very low concentrations. Pathogenic (tdh- or trh2-positive) V. parahaemolyticus were present in water, sediment and shellfish samples collected from these lagoons. The number of V. vulnificus in water, sediment and shellfish samples ranged from 1 to 1.1 {\texttimes} 103 MPN/l, 0.07 to 110 MPN/ml and 0.04 to 15 MPN/g, respectively, during summer. V. vulnificus was not detected during winter. V. cholerae was rarely detected in water and sediment during summer. In summary, results of this study highlight the finding that the three human pathogenic Vibrio spp. are present in the lagoons and constitute a potential public health hazard.}, issn = {09232508}, doi = {10.1016/j.resmic.2013.06.005}, url = {https://linkinghub.elsevier.com/retrieve/pii/S092325081300106X}, author = {Cantet, Franck and Hervio-Heath, Dominique and Caro, Audrey and Le Mennec, C{\'e}cile and Monteil, Caroline and Qu{\'e}m{\'e}r{\'e}, Catherine and Jolivet-Gougeon, Anne and Rita R Colwell and Monfort, Patrick} } @article {19668, title = {Quantitative measurement of allele-specific protein expression in a diploid yeast hybrid by LC-MS}, journal = {Molecular Systems Biology}, volume = {8}, year = {2012}, month = {2012/01/01/}, abstract = {Understanding the genetic basis of gene regulatory variation is a key goal of evolutionary and medical genetics. Regulatory variation can act in an allele-specific manner (cis-acting) or it can affect both alleles of a gene (trans-acting). Differential allele-specific expression (ASE), in which the expression of one allele differs from another in a diploid, implies the presence of cis-acting regulatory variation. While microarrays and high-throughput sequencing have enabled genome-wide measurements of transcriptional ASE, methods for measurement of protein ASE (pASE) have lagged far behind. We describe a flexible, accurate, and scalable strategy for measurement of pASE by liquid chromatography-coupled mass spectrometry (LC-MS). We apply this approach to a hybrid between the yeast species Saccharomyces cerevisiae and Saccharomyces bayanus. Our results provide the first analysis of the relative contribution of cis-acting and trans-acting regulatory differences to protein expression divergence between yeast species.Synopsis A novel strategy for the quantitative measurement of allele-specific protein expression is used to infer the contributions of cis- and trans-acting factors influencing the divergence of protein levels between yeast species. Rigorous experimental controls and analyses confirm the accuracy of the new strategy for the quantitative measurement of allele-specific protein expression by high-throughput mass spectrometry.Analysis of allele-specific protein expression in an interspecies yeast hybrid and protein expression differences between species reveals that both cis-effects and trans-effects contribute to protein expression divergence between two yeast species, Saccharomyces cerevisiae and Saccharomyces bayanus. }, keywords = {allele specific, divergence, mass spectrometry, protein expression, proteomics}, url = {http://msb.embopress.org/content/8/1/602}, author = {Zia Khan and Bloom, Joshua S. and Amini, Sasan and Singh, Mona and Perlman, David H. and Caudy, Amy A. and Kruglyak, Leonid} } @article {16030, title = {Querying event sequences by exact match or similarity search: Design and empirical evaluation}, journal = {Interacting with Computers}, volume = {24}, year = {2012}, month = {2012/03//}, pages = {55 - 68}, abstract = {Specifying event sequence queries is challenging even for skilled computer professionals familiar with SQL. Most graphical user interfaces for database search use an exact match approach, which is often effective, but near misses may also be of interest. We describe a new similarity search interface, in which users specify a query by simply placing events on a blank timeline and retrieve a similarity-ranked list of results. Behind this user interface is a new similarity measure for event sequences which the users can customize by four decision criteria, enabling them to adjust the impact of missing, extra, or swapped events or the impact of time shifts. We describe a use case with Electronic Health Records based on our ongoing collaboration with hospital physicians. A controlled experiment with 18 participants compared exact match and similarity search interfaces. We report on the advantages and disadvantages of each interface and suggest a hybrid interface combining the best of both.}, keywords = {Event sequence, Similan, similarity measure, Similarity Search, temporal categorical data, Temporal query interface}, isbn = {0953-5438}, doi = {10.1016/j.intcom.2012.01.003}, url = {http://www.sciencedirect.com/science/article/pii/S0953543812000124}, author = {Wongsuphasawat,Krist and Plaisant, Catherine and Taieb-Maimon,Meirav and Shneiderman, Ben} } @article {15108, title = {Quid Pro Quo-tocols: Strengthening Semi-Honest Protocols with Dual Execution}, journal = {IEEE Symposium on Security and Privacy}, year = {2012}, month = {2012///}, abstract = {Known protocols for secure two-party computa-tion that are designed to provide full security against malicious behavior are significantly less efficient than protocols intended only to thwart semi-honest adversaries. We present a concrete design and implementation of protocols achieving security guarantees that are much stronger than are possible with semi-honest protocols, at minimal extra cost. Specifically, we consider protocols in which a malicious adversary may learn a single (arbitrary) bit of additional information about the honest party{\textquoteright}s input. Correctness of the honest party{\textquoteright}s output is still guaranteed. Adapting prior work of Mohassel and Franklin, the basic idea in our protocols is to conduct two separate runs of a (specific) semi-honest, garbled-circuit protocol, with the parties swapping roles, followed by an inexpensive secure equality test. We provide a rigorous definition and prove that this protocol leaks no more than one additional bit against a malicious adversary. In addition, we propose some heuristic enhancements to reduce the overall information a cheating adversary learns. Our experiments show that protocols meeting this security level can be implemented at cost very close to that of protocols that only achieve semi-honest security. Our results indicate that this model enables the large-scale, practical applications possible within the semi-honest security model, while providing stronger security guarantees. }, author = {Huang,Y. and Katz, Jonathan and Evans,D.} } @article {16817, title = {Query Processing Using Distance Oracles for Spatial Networks}, journal = {Knowledge and Data Engineering, IEEE Transactions on}, volume = {22}, year = {2010}, month = {2010/08//}, pages = {1158 - 1175}, abstract = {The popularity of location-based services and the need to do real-time processing on them has led to an interest in performing queries on transportation networks, such as finding shortest paths and finding nearest neighbors. The challenge here is that the efficient execution of spatial operations usually involves the computation of distance along a spatial network instead of "as the crow flies, $\#$x0201D; which is not simple. Techniques are described that enable the determination of the network distance between any pair of points (i.e., vertices) with as little as O(n) space rather than having to store the n^2 distances between all pairs. This is done by being willing to expend a bit more time to achieve this goal such as O(log n) instead of O(1), as well as by accepting an error varepsilon in the accuracy of the distance that is provided. The strategy that is adopted reduces the space requirements and is based on the ability to identify groups of source and destination vertices for which the distance is approximately the same within some varepsilon. The reductions are achieved by introducing a construct termed a distance oracle that yields an estimate of the network distance (termed the varepsilon-approximate distance) between any two vertices in the spatial network. The distance oracle is obtained by showing how to adapt the well-separated pair technique from computational geometry to spatial networks. Initially, an varepsilon-approximate distance oracle of size O(nover varepsilon^2 ) is used that is capable of retrieving the approximate network distance in O(log n) time using a B-tree. The retrieval time can be theoretically reduced further to O(1) time by proposing another varepsilon-approximate distance oracle of size O(n log nover varepsilon^2 ) that uses a hash table. Experimental results indicate that the proposed technique is scalable and can be applied to sufficiently large road networks. For example, a 10-percent-approximate oracle (vareps- - ilon = 0.1) on a large network yielded an average error of 0.9 percent with 90 percent of the answers having an error of 2 percent or less and an average retrieval time of 68 mu rm seconds. The fact that the network distance can be approximated by one value is used to show how a number of spatial queries can be formulated using appropriate SQL constructs and a few built-in primitives. The result is that these operations can be executed on almost any modern database with no modifications, while taking advantage of the existing query optimizers and query processing strategies.}, isbn = {1041-4347}, doi = {10.1109/TKDE.2010.75}, author = {Sankaranarayanan,Jagan and Samet, Hanan} } @article {15792, title = {Quadratic fermionic interactions yield Hamiltonians with large ground-state energy gaps}, journal = {Physical Review APhys. Rev. A}, volume = {79}, year = {2009}, month = {2009/03/24/}, pages = {032331 - 032331}, abstract = {Polynomially large ground-state energy gaps are rare in many-body quantum systems, but useful in quantum information and an interesting feature of the one-dimensional quantum Ising model. We show analytically that the gap is generically polynomially large not just for the quantum Ising model, but for one-, two-, and three-dimensional interaction lattices and Hamiltonians with certain random interactions. We extend the analysis to Hamiltonian evolutions and we use the Jordan-Wigner transformation and a related transformation for spin-3/2 particles to show that our results can be restated using spin operators in a surprisingly simple manner. These results also yield a new perspective on the one-dimensional cluster state.}, doi = {10.1103/PhysRevA.79.032331}, url = {http://link.aps.org/doi/10.1103/PhysRevA.79.032331}, author = {O{\textquoteright}Hara,Michael J. and O{\textquoteright}Leary,Dianne P.} } @article {16061, title = {Querying timestamped event sequences by exact search or similarity-based search: design and empirical evaluation}, volume = {HCIL-2009-20}, year = {2009}, month = {2009///}, institution = {Human-Computer Interaction Lab, University of Maryland}, author = {Wongsuphasawat,K. and Plaisant, Catherine and Shneiderman, Ben} } @article {15790, title = {QCS: A system for querying, clustering and summarizing documents}, journal = {Information Processing \& Management}, volume = {43}, year = {2007}, month = {2007/11//}, pages = {1588 - 1605}, abstract = {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 integrated information retrieval system{\textemdash}the Query, Cluster, Summarize (QCS) system{\textemdash}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 methods 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) as measured by 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 {\textquotedblleft}trimming{\textquotedblright} 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, and the value of this particular combination of modules. }, keywords = {clustering, Information retrieval, latent semantic indexing, Sentence trimming, Summarization, TEXT PROCESSING}, isbn = {0306-4573}, doi = {10.1016/j.ipm.2007.01.003}, url = {http://www.sciencedirect.com/science/article/pii/S0306457307000246}, author = {Dunlavy,Daniel M. and O{\textquoteright}Leary,Dianne P. and Conroy,John M. and Schlesinger,Judith D.} } @article {18504, title = {Quantifying the effects of routing dynamics on end-to-end Internet path failures}, volume = {TR-05-CSE-03}, year = {2006}, month = {2006///}, institution = {University of Massachusetts}, author = {Wang,F. and Feamster, Nick and Gao,L.} } @article {15245, title = {Query planning in the presence of overlapping sources}, journal = {Advances in Database Technology-EDBT 2006}, year = {2006}, month = {2006///}, pages = {811 - 828}, abstract = {Navigational queries on Web-accessible life science sources pose unique query optimization challenges. The objects in these sources are interconnected to objects in other sources, forming a large and complex graph, and there is an overlap of objects in the sources. Answering a query requires the traversal of multiple alternate paths through these sources. Each path can be associated with the benefit or the cardinality of the target object set (TOS) of objects reached in the result. There is also an evaluation cost of reaching the TOS.We present dual problems in selecting the best set of paths. The first problem is to select a set of paths that satisfy a constraint on the evaluation cost while maximizing the benefit (number of distinct objects in the TOS). The dual problem is to select a set of paths that satisfies a threshold of the TOS benefit with minimal evaluation cost. The two problems can be mapped to the budgeted maximum coverage problem and the maximal set cover with a threshold. To solve these problems, we explore several solutions including greedy heuristics, a randomized search, and a traditional IP/LP formulation with bounds. We perform experiments on a real-world graph of life sciences objects from NCBI and report on the computational overhead of our solutions and their performance compared to the optimal solution. }, doi = {10.1007/11687238_48}, author = {Bleiholder,J. and Khuller, Samir and Naumann,F. and Raschid, Louiqa and Wu,Y.} } @article {16469, title = {Query planning in the presence of overlapping sources}, journal = {Advances in Database Technology-EDBT 2006}, year = {2006}, month = {2006///}, pages = {811 - 828}, author = {Bleiholder,J. and Khuller, Samir and Naumann,F. and Raschid, Louiqa and Wu,Y.} } @conference {16472, title = {Query Rewriting in the Semantic Web7}, booktitle = {Data Engineering Workshops, 22nd International Conference on}, year = {2006}, month = {2006///}, pages = {7 - 7}, publisher = {IEEE Computer Society}, organization = {IEEE Computer Society}, address = {Los Alamitos, CA, USA}, abstract = {The widespread explosion of Web accessible resources has lead to a new challenge of locating all relevant resources and identifying the best ones to answer a query. This challenge has to address the difficult task of ranking the resources based on user needs, as well as the more expensive computational task of determining all the solutions to answer a query. In this paper, we define a Top K problem for query rewriting on the Semantic Web. We first introduce a three level data model composed of the ontology level, the physical level of the physical resources, and the data level composed of the entries in the different resources. We present a query language for Top K navigational queries over ontology concepts. We then sketch the outline of an efficient search algorithm to compute an approximation of the Top K rewriting options to produce source paths among the physical resources. We briefly discuss the results of an experimental study}, isbn = {0-7695-2571-7}, doi = {http://doi.ieeecomputersociety.org/10.1109/ICDEW.2006.124}, author = {Vidal,Maria Esther and Raschid, Louiqa and Marquez,Natalia and Cardenas,Marelis and Yao Wu} } @conference {14407, title = {Query-time entity resolution}, booktitle = {International conference on knowledge discovery and data mining}, year = {2006}, month = {2006///}, pages = {529 - 534}, abstract = {The goal of entity resolution is to reconcile database references corresponding to the same real-world entities. Given the abundance of publicly available databases where entities are not resolved, we motivate the problem of quickly processing queries that require resolved entities from such {\textquoteright}unclean{\textquoteright} databases. We propose a two-stage collective resolution strategy for processing queries. We then show how it can be performed on-the-fly by adaptively extracting and resolving those database references that are the most helpful for resolving the query. We validate our approach on two large real-world publication databases where we show the usefulness of collective resolution and at the same time demonstrate the need for adaptive strategies for query processing. We then show how the same queries can be answered in real time using our adaptive approach while preserving the gains of collective resolution.}, author = {BHATTACHARVA,I. and Getoor, Lise and Licamele,L.} } @article {15791, title = {QR Factorizations Using a Restricted Set of Rotations}, journal = {Electronic Transactions on Numerical Analysis}, volume = {21}, year = {2005}, month = {2005///}, pages = {20 - 27}, url = {http://etna.mcs.kent.edu/vol.21.2005/pp20-27.dir/pp20-27.pdfhttp://etna.mcs.kent.edu/vol.21.2005/pp20-27.dir/pp20-27.pdf}, author = {O{\textquoteright}Leary, Dianne P. and Bullock,Stephen S.} } @conference {17890, title = {Query planning for the grid: adapting to dynamic resource availability}, booktitle = {Cluster Computing and the Grid, IEEE International Symposium on}, volume = {2}, year = {2005}, month = {2005///}, pages = {751 - 758}, publisher = {IEEE Computer Society}, organization = {IEEE Computer Society}, address = {Los Alamitos, CA, USA}, abstract = {The availability of massive datasets, comprising sensor measurements or the results of scientific simulations, has had a significant impact on the methodology of scientific reasoning. Scientists require storage, bandwidth and computational capacity to query and analyze these datasets, to understand physical phenomena or to test hypotheses. This paper addresses the challenge of identifying and selecting resources to develop an evaluation plan for large scale data analysis queries when data processing capabilities and datasets are dispersed across nodes in one or more computing and storage clusters. We show that generating an optimal plan is hard and we propose heuristic techniques to find a good choice of resources. We also consider heuristics to cope with dynamic resource availability; in this situation we have stale information about reusable cached results (datasets) and the load on various nodes.}, isbn = {0-7803-9074-1}, doi = {http://doi.ieeecomputersociety.org/10.1109/CCGRID.2005.1558638}, author = {Zhang,K. and Andrade,H. and Raschid, Louiqa and Sussman, Alan} } @conference {16774, title = {Querying structured data in an unstructured P2P system}, booktitle = {Proceedings of the 6th annual ACM international workshop on Web information and data management - WIDM {\textquoteright}04}, year = {2004}, month = {2004///}, pages = {64 - 64}, address = {Washington DC, USA}, doi = {10.1145/1031453.1031466}, url = {http://dl.acm.org/citation.cfm?id=1031466}, author = {Kantere,Verena and Tsoumakos,Dimitrios and Roussopoulos, Nick} } @conference {16493, title = {Querying Web-Accessible Life Science Sources: Which paths to choose?}, booktitle = {Proceedings of VLDB Workshop on Information Integration on the Web (IIWeb-2004)}, year = {2004}, month = {2004///}, pages = {83 - 83}, author = {Bleiholder,J. and Naumann,F. and Raschid, Louiqa and Vidal,M. E} } @article {17522, title = {Quantifying the causes of path inflation}, journal = {Topology}, volume = {100}, year = {2003}, month = {2003///}, pages = {2 - 1}, author = {Spring, Neil and Mahajan,R. and Anderson,T.} } @article {16486, title = {A query language to support scientific discovery}, journal = {Proc. 2nd IEEE International Computer Society}, year = {2003}, month = {2003///}, author = {Eckman,B. and Deutsch,K. and Janer,M. and Lacroix,Z. and Raschid, Louiqa} } @conference {15318, title = {Question answering from the web using knowledge annotation and knowledge mining techniques}, booktitle = {Proceedings of the twelfth international conference on Information and knowledge management}, series = {CIKM {\textquoteright}03}, year = {2003}, month = {2003///}, pages = {116 - 123}, publisher = {ACM}, organization = {ACM}, address = {New York, NY, USA}, abstract = {We present a strategy for answering fact-based natural language questions that is guided by a characterization of real-world user queries. Our approach, implemented in a system called Aranea, extracts answers from the Web using two different techniques: knowledge annotation and knowledge mining. Knowledge annotation is an approach to answering large classes of frequently occurring questions by utilizing semi\-structured and structured Web sources. Knowledge mining is a statistical approach that leverages massive amounts of Web data to overcome many natural language processing challenges. We have integrated these two different paradigms into a question answering system capable of providing users with concise answers that directly address their information needs.}, keywords = {data-redundancy, semistructured data}, isbn = {1-58113-723-0}, doi = {10.1145/956863.956886}, url = {http://doi.acm.org/10.1145/956863.956886}, author = {Jimmy Lin and Katz,Boris} } @article {15322, title = {Question answering techniques for the World Wide Web}, journal = {Tutorial presentation at The 11th Conference of the European Chapter of the Association of Computational Linguistics (EACL-2003)}, year = {2003}, month = {2003///}, abstract = {Question answering systems have become increasingly popular because they deliverusers short, succinct answers instead of overloading them with a large number of irrelevant documents. The vast amount of information readily available on the World Wide Web presents new opportunities and challenges for question answering. In order for question answering systems to benefit from this vast store of useful knowledge, they must cope with large volumes of useless data. Many characteristics of the World Wide Web distinguish Web-based question answering from question answering on closed corpora such as newspaper texts. The Web is vastly larger in size and boasts incredible {\textquotedblleft}data redundancy,{\textquotedblright} which renders it amenable to statistical techniques for answer extraction. A data-driven approach can yield high levels of performance and nicely complements traditional question answering techniques driven by information extraction. In addition to enormous amounts of unstructured text, the Web also contains pockets of structured and semistructured knowledge that can serve as a valuable resource for question answering. By organizing these resources and annotating them with natural language, we can successfully incorporate Web knowledge into question answering systems. This tutorial surveys recent Web-based question answering technology, focusing on two separate paradigms: knowledge mining using statistical tools and knowledge annotation using database concepts. Both approaches can employ a wide spectrum of techniques ranging in linguistic sophistication from simple {\textquotedblleft}bag-of-words{\textquotedblright} treatments to full syntactic parsing. }, author = {Jimmy Lin and Katz,B.} } @conference {18690, title = {Quantifying the cost of providing intrusion tolerance in group communication systems}, year = {2002}, month = {2002///}, pages = {229 - 238}, abstract = {Group communication systems that provide consistent group membership and reliable, ordered multicast properties in the presence of faults resulting from malicious intrusions have not been analyzed extensively to quantify the cost of tolerating these intrusions. This paper attempts to quantify this cost by presenting results from an experimental evaluation of three new intrusion-tolerant microprotocols that have been added to an existing crash-fault-tolerant group communication system. The results are analyzed to identify the parts that contribute the most overhead during provision of intrusion tolerance at the group communication system level.}, keywords = {consistent group membership, crash-fault-tolerant group communication system, cryptography, finite state machines, groupware, intrusion-tolerant microprotocols, malicious intrusions, multicast communication, reliable ordered multicast properties, security of data, Transport protocols}, doi = {10.1109/DSN.2002.1028904}, author = {Ramasamy,H. V. and Pandey,P. and Lyons,J. and Michel Cukier and Sanders,W. H.} } @conference {12761, title = {Quasi-invariants for human action representation and recognition}, booktitle = {Pattern Recognition, 2002. Proceedings. 16th International Conference on}, volume = {1}, year = {2002}, month = {2002///}, pages = {307 - 310 vol.1 - 307 - 310 vol.1}, abstract = {Although human action recognition has been the subject of much research in the past, the issue of viewpoint invariance has received scarce attention. In this paper, we present an approach to detect human action with a high tolerance to viewpoint change. Canonical body poses are modeled in a view invariant manner to enable detection from a general viewpoint. While there exist no invariants for 3D to 2D projection, there exists a wealth of techniques in 2D invariance that can be used to advantage in 3D to 2D projection. We employ 2D invariants to recognize canonical poses of the human body leading to an effective way to represent and recognize human action which we evaluate theoretically and experimentally on 2D projections of publicly available human motion capture data.}, keywords = {2D, action, analysis;, body, canonical, change, human, image, invariance;, MOTION, poses;, quasi-invariants;, recognition;, representation;, tolerance;, viewpoint}, doi = {10.1109/ICPR.2002.1044699}, author = {Parameswaran, V. and Chellapa, Rama} } @conference {12310, title = {Query routing in the TerraDir distributed directory}, booktitle = {Proceedings of the SPIE ITCOM}, volume = {4868}, year = {2002}, month = {2002///}, pages = {299 - 309}, abstract = {We present the design and evaluation of the query-routing protocol of the TerraDir distributed directory.TerraDir is a wide-area distributed directory designed for hierarchical namespaces, and provides a lookup service for mapping keys to objects. We introduce distributed lookup and caching algorithms that leverage the underlying data hierarchy. Our algorithms provide efficient lookups while avoiding the load imbalances often associated with hierarchical systems. The TerraDir load balancing scheme also incorporates a node replication algorithm that provides configurable failure resilience with provably low overheads. }, author = {Silaghi,B. and Bhattacharjee, Bobby and Keleher,P.} } @article {15607, title = {Quantile approximation for robust statistical estimation and k-enclosing problems}, journal = {International Journal of Computational Geometry and Applications}, volume = {10}, year = {2000}, month = {2000///}, pages = {593 - 608}, abstract = {Given a set P of n points in Rd, a fundamental problem in computational geometryis concerned with finding the smallest shape of some type that encloses all the points of P. Well-known instances of this problem include finding the smallest enclosing box, minimum volume ball, and minimum volume annulus. In this paper we consider the following variant: Given a set of n points in Rd, find the smallest shape in question that contains at least k points or a certain quantile of the data. This type of problem is known as a k-enclosing problem. We present a simple algorithmic framework for computing quantile approximations for the minimum strip, ellipsoid, and annulus containing a given quantile of the points. The algorithms run in O(n log n) time. }, author = {Mount, Dave and Netanyahu,N. S and Piatko,C. D and Silverman,R. and Wu,A. Y} } @article {17737, title = {The QLP Approximation to the Singular Value Decomposition}, journal = {SIAM Journal on Scientific Computing}, volume = {20}, year = {1999}, month = {1999///}, pages = {1336 - 1348}, abstract = {In this paper we introduce a new decomposition called the pivoted QLP decomposition. It is computed by applying pivoted orthogonal triangularization to the columns of the matrix X in question to get an upper triangular factor R and then applying the same procedure to the rows of R to get a lower triangular matrix L. The diagonal elements of R are called the R-values of X; those of L are called the L-values. Numerical examples show that the L-values track the singular values of X with considerable fidelity---far better than the R-values. At a gap in the L-values the decomposition provides orthonormal bases of analogues of row, column, and null spaces provided of X. The decomposition requires no more than twice the work required for a pivoted QR decomposition. The computation of R and L can be interleaved, so that the computation can be terminated at any suitable point, which makes the decomposition especially suitable for low-rank determination problems. The interleaved algorithm also suggests a new, efficient 2-norm estimator.}, keywords = {pivoted QR decomposition, QLP decomposition, rank determination, singular value decomposition}, doi = {10.1137/S1064827597319519}, url = {http://link.aip.org/link/?SCE/20/1336/1}, author = {Stewart, G.W.} } @conference {17871, title = {Querying Very Large Multi-dimensional Datasets in ADR}, booktitle = {In Proceedings of SC99: High Performance Networking and Computing}, year = {1999}, month = {1999///}, author = {Chialin,T. K and Kurc, T. and Chang,C. and Ferreira,R. and Sussman, Alan and Saltz, J.} } @article {17731, title = {QR Sometimes Beats Jacobi}, volume = {UMIACS-TR-95-32}, year = {1998}, month = {1998/10/15/}, institution = {Instititue for Advanced Computer Studies, Univ of Maryland, College Park}, abstract = {This note exhibits a symmetric matrix having a small eigenvalue that iscomputed accurately by the QR algorithm but not by Jacobi{\textquoteright}s method. (Also cross-referenced as UMIACS-TR-95-32) }, keywords = {Technical Report}, url = {http://drum.lib.umd.edu/handle/1903/709}, author = {Stewart, G.W.} } @article {16199, title = {Query previews for networked information systems: a case study with NASA environmental data}, journal = {SIGMOD Record}, volume = {26}, year = {1997}, month = {1997///}, pages = {75 - 81}, abstract = {Formulating queries on networked information systemsis laden with problems: data diversity, data complexity, network growth, varied user base, and slow network access. This paper proposes a new approach to a network query user interface which consists of two phases: query preview and query refinement. This new approach is based on dynamic queries and tight coupling, guiding users to rapidly and dynamically eliminate undesired items, reduce the data volume to a manageable size, and refine queries locally before submission over a network. A two-phase dynamic query system for NASA{\textquoteright}s Earth Observing Systems--Data Information Systems (EOSDIS) is presented. The prototype was well received by the team of scientists who evaluated the interface. }, author = {Doan,K. and Plaisant, Catherine and Shneiderman, Ben and Bruns,T.} } @conference {16196, title = {Query previews in networked information systems: the case of EOSDIS}, booktitle = {CHI {\textquoteright}97 extended abstracts on Human factors in computing systems: looking to the future}, series = {CHI EA {\textquoteright}97}, year = {1997}, month = {1997///}, pages = {202 - 203}, publisher = {ACM}, organization = {ACM}, address = {New York, NY, USA}, abstract = {Dynamic queries have been shown to be an effective technique to browse information, and to find patterns and exceptions. Dynamic queries involve the interactive control by a user of visual query parameters that generate rapid (100 ms update), animated, and visual displays of database search results. The data of early implementations was stored in local memory to guarantee optimal speed. Problems arise when the data is very large and distributed over a network. To overcome the problems of slow networks and data volume we propose a two-phase approach to query formulation using query previews and query refinements [1]. Preview mechanisms have been used in the past [2] and we believe that their use will be a major component of successful networked information systems interfaces (e.g. [3]).}, keywords = {direct manipulation, dynamic query, earth science, network information system, query preview, Visualization}, isbn = {0-89791-926-2}, doi = {10.1145/1120212.1120343}, url = {http://doi.acm.org/10.1145/1120212.1120343}, author = {Plaisant, Catherine and Bruns,Tom and Shneiderman, Ben and Doan,Khoa} } @conference {14249, title = {Qualitative depth and FOE information via smoothed flow}, booktitle = {Proceedings of the 20th workshop of the Austrian Association for Pattern Recognition (OAGM/AAPR) on Pattern recognition 1996}, year = {1996}, month = {1996///}, pages = {207 - 213}, publisher = {R. Oldenbourg Verlag GmbH}, organization = {R. Oldenbourg Verlag GmbH}, address = {Munich, Germany, Germany}, isbn = {3-486-23865-5}, url = {http://dl.acm.org/citation.cfm?id=258081.258100}, author = {Shulman,David and Ferm{\"u}ller, Cornelia} } @inbook {13627, title = {Quantitative Measurement of the Performance of Raster-to-vector Conversion Algorithms}, booktitle = {Graphics Recognition: Methods and ApplicationsGraphics Recognition: Methods and Applications}, year = {1996}, month = {1996///}, pages = {57 - 68}, publisher = {Springer}, organization = {Springer}, author = {Hori,O. and David Doermann} } @conference {16201, title = {Query previews in networked information systems}, booktitle = {Research and Technology Advances in Digital Libraries, 1996. ADL {\textquoteright}96., Proceedings of the Third Forum on}, year = {1996}, month = {1996/05//}, pages = {120 - 129}, abstract = {In a networked information system (such as the NASA Earth Observing System-Data Information System (EOS-DIS)), there are three major obstacles facing users in a querying process: network performance, data volume and data complexity. In order to overcome these obstacles, we propose a two phase approach to query formulation. The two phases are the Query Preview and the Query Refinement. In the Query Preview phase, users formulate an initial query by selecting rough attribute values. The estimated number of matching data sets is shown, graphically on preview bars which allows users to rapidly focus on a manageable number of relevant data sets. Query previews also prevent wasted steps by eliminating zero hit queries. When the estimated number of data sets is long enough, the initial query is submitted to the network which returns the metadata of the data sets for further refinement in the Query Refinement phase. The two phase approach to query formulation overcomes slow network performance, and reduces the data volume and data complexity, problems. This approach is especially appropriate for users who do not have extensive knowledge about the data and who prefer an exploratory method to discover data patterns and exceptions. Using this approach, we have developed dynamic query user interfaces to allow users to formulate their queries across a networked environment}, keywords = {attribute, complexity;data, data, Earth, environment;networked, EOS-DIS;NASA, formulation;querying, formulation;user, hit, information, interfaces;, interfaces;exploratory, method;matching, networks;information, Observing, patterns;data, performance;networked, Preview;Query, process;rough, queries;computer, query, refinement;data, retrieval;information, services;interactive, sets;network, System-Data, System;Query, systems;query, user, values;zero, volume;dynamic}, doi = {10.1109/ADL.1996.502522}, author = {Donn,K. and Plaisant, Catherine and Shneiderman, Ben} } @conference {17335, title = {Query previews in networked information systems}, booktitle = {Proceedings of the Third Forum on Research and Technology Advances in Digital Libraries, 1996. ADL {\textquoteright}96}, year = {1996}, month = {1996/05/13/15}, pages = {120 - 129}, publisher = {IEEE}, organization = {IEEE}, abstract = {In a networked information system (such as the NASA Earth Observing System-Data Information System (EOS-DIS)), there are three major obstacles facing users in a querying process: network performance, data volume and data complexity. In order to overcome these obstacles, we propose a two phase approach to query formulation. The two phases are the Query Preview and the Query Refinement. In the Query Preview phase, users formulate an initial query by selecting rough attribute values. The estimated number of matching data sets is shown, graphically on preview bars which allows users to rapidly focus on a manageable number of relevant data sets. Query previews also prevent wasted steps by eliminating zero hit queries. When the estimated number of data sets is long enough, the initial query is submitted to the network which returns the metadata of the data sets for further refinement in the Query Refinement phase. The two phase approach to query formulation overcomes slow network performance, and reduces the data volume and data complexity, problems. This approach is especially appropriate for users who do not have extensive knowledge about the data and who prefer an exploratory method to discover data patterns and exceptions. Using this approach, we have developed dynamic query user interfaces to allow users to formulate their queries across a networked environment}, keywords = {Computer networks, data complexity, data mining, data patterns, data volume, dynamic query user interfaces, Educational institutions, EOS-DIS, exploratory method, Information retrieval, Information services, Information systems, Intelligent networks, interactive systems, Laboratories, Manipulator dynamics, matching data sets, NASA Earth Observing System-Data Information System, Network performance, networked environment, networked information systems, query formulation, query preview, query refinement, querying process, rough attribute values, User interfaces, visual databases, zero hit queries}, isbn = {0-8186-7403-2}, doi = {10.1109/ADL.1996.502522}, author = {Donn,K. and Plaisant, Catherine and Shneiderman, Ben} } @article {14250, title = {Qualitative egomotion}, journal = {International Journal of Computer Vision}, volume = {15}, year = {1995}, month = {1995///}, pages = {7 - 29}, abstract = {Due to the aperture problem, the only motion measurement in images, whose computation does not require any assumptions about the scene in view, is normal flow{\textemdash}the projection of image motion on the gradient direction. In this paper we show how a monocular observer can estimate its 3D motion relative to the scene by using normal flow measurements in a global and qualitative way. The problem is addressed through a search technique. By checking constraints imposed by 3D motion parameters on the normal flow field, the possible space of solutions is gradually reduced. In the four modules that comprise the solution, constraints of increasing restriction are considered, culminating in testing every single normal flow value for its consistency with a set of motion parameters. The fact that motion is rigid defines geometric relations between certain values of the normal flow field. The selected values form patterns in the image plane that are dependent on only some of the motion parameters. These patterns, which are determined by the signs of the normal flow values, are searched for in order to find the axes of translation and rotation. The third rotational component is computed from normal flow vectors that are only due to rotational motion. Finally, by looking at the complete data set, all solutions that cannot give rise to the given normal flow field are discarded from the solution space.}, isbn = {0920-5691}, url = {http://dx.doi.org/10.1007/BF01450848}, author = {Ferm{\"u}ller, Cornelia and Aloimonos, J.} } @article {11972, title = {Qualitative vision}, journal = {International Journal of Computer Vision}, volume = {14}, year = {1995}, month = {1995///}, pages = {115 - 117}, author = {Aloimonos, J.} } @article {16207, title = {QUERY PREVIEWS IN NETWORKED INFORMATION SYSTEMS}, journal = {Institute for Systems Research Technical Reports}, year = {1995}, month = {1995/10//}, abstract = {In a networked information system, there are three major obstacles facing users in a querying process: network performance, data volume and data complexity. In order to overcome these obstacles, we propose a two-phase approach to dynamic query formulation by volume preview. The two phases are the Query Preview and Query Refinement. In the Query Preview phase, users formulate an initial query by selecting desired attribute values. The volume of matching data sets is shown graphically on preview bars which aid users to rapidly eliminate undesired data sets, and focus on a manageable number of relevant data sets. Query previews also prevent wasted steps by eliminating zero-hit queries. When the estimated number of data sets is low enough, the initial query is submitted to the network, which returns the metadata of the data sets for further refinement in the Query Refinement phase. The two-phase approach to query formulation overcomes slow network performance, and reduces the data volume and data complexity problems. This approach is especially appropriate for users who prefer the exploratory method to discover data patterns and exceptions during the query formulation process. Using this approach, we have developed dynamic query user interfaces to allow users to formulate their queries across a networked environment.}, author = {Doan,K. and Plaisant, Catherine and Shneiderman, Ben} } @article {13845, title = {Query transformation techniques for interoperable query processing in cooperative information systems}, journal = {Proceedings of the Second International Conference on Cooperative Information Systems (CoopIS94), May}, year = {1994}, month = {1994///}, pages = {17 - 20}, author = {Raschid, Louiqa and Chang,Y. and Dorr, Bonnie J} } @conference {15641, title = {Query-sensitive ray shooting}, booktitle = {Proceedings of the tenth annual symposium on Computational geometry}, series = {SCG {\textquoteright}94}, year = {1994}, month = {1994///}, pages = {359 - 368}, publisher = {ACM}, organization = {ACM}, address = {New York, NY, USA}, isbn = {0-89791-648-4}, doi = {10.1145/177424.178094}, url = {http://doi.acm.org/10.1145/177424.178094}, author = {Mitchell,Joseph S.B. and Mount, Dave and Suri,Subhash} } @article {17337, title = {QUEST{\textemdash}Query Environment for Science Teaching}, journal = {Digital Libraries{\textquoteright} 94}, year = {1994}, month = {1994///}, abstract = {QUery Environment for Science Teaching (QUEST) is a proposed digital library implementation consisting of a set of research projects dealing with data capture and organization, content analysis, information seeking and visual interfaces.The QUEST team includes a large number of renown technical collaborators and prominent source collaborators, as well as a significant number of contributors in the University of Maryland, the central, co-ordinating agency.A large collection of multidisciplinary materials in visual and textual formats, made accessible to us by our source collaborators, will be organized to allow integrated access by users from the science education community, that is elementary school through college level teachers. QUEST will be structured so as to provide seamless access to widespread resources on disparate subjects. We intend to provide first-rate subject analysis and representation in order to provide ready access. QUEST will be accessible nationally by means of Mosaic. We propose to provide highly sophisticated querying, browsing and information investigation facilities which will handle integrated textual and visual materials without difficulty. They will be augmented by online reference and referral services, immediately accessible by the user. QUEST will provide a comprehensive information resource for science education accessible through a dynamic, visual user interface. }, author = {Shneiderman, Ben and Rosenfeld, A. and Marchioni,G. and Holliday,W. and Ricart, G. and Faloutsos,ะก. and Dick,J.} } @article {13844, title = {Query mapping and transformation techniques for problem solving with multiple knowledge servers}, journal = {Proceedings of the Second International Conference on Information and Knowledge Management (CIKM-93)}, year = {1993}, month = {1993///}, abstract = {This paper describes a technique for infor-mation mediation when multiple heterogeneous knowl- edge and data servers are to be accessed during query processing. One problem is building an intelligent in- terface between each knowledge server (KS) and its processor (KP); and the second is to provide interoper- ability among multiple KP/KS so that a query may be answered using information from multiple sources. We present example scenarios which highlight these prob- lems and then outline query mapping and transforma- tion techniques that are applicable. The techniques for solving the interoperability problems involve rep- resentations in some canonical form. This includes a canonical representation (CR) corresponding to each KP/KS pair and a merged CR (MCR) to represent the mapping among the CRs. The MCR and CRs include relevant information obtained from a source query, and heterogeneous mapping (het-map) information, for all possible mappings among the multiple servers. The knowledge in the canonical form must be represented so that it can be easily accessed during query transfor- mation. We use an example of translating queries from an object schema to a relational schema to illustrate typical knowledge that must be represented in some canonical form. We use a high level logical language, F-logic, to represent the heterogeneous mapping (het- map) and query transformation information as a set of declarative rules, in the canonical form. }, author = {Raschid, Louiqa and Chang,Y. and Dorr, Bonnie J} }