Distribution by Scientific Domains
Distribution within Information Science and Computing

Kinds of Queries

  • user query

  • Terms modified by Queries

  • query expansion
  • query language
  • query sequence
  • query term

  • Selected Abstracts

    Using semantic links to support top- K join queries in peer-to-peer networks

    Jie Liu
    Abstract An important issue raised in peer-to-peer (P2P) applications is how to accurately and efficiently retrieve a set of K best matching data objects from different sources while minimizing the number of objects that have to be accessed. The proposed solution is to organize peers by a semantic link network representing the semantic relationships between peers' data schemas. Queries are only routed to semantically relevant peers. A pruning-based local top- K ranking approach is proposed to reduce the transmitted data by pruning tuples that cannot produce the desired join results with a rank value at least equal to the lowest rank value generated. Experiments evaluate its performance in terms of the number of transmitted tuples and the miss rate. Comparison with the traditional threshold algorithm for centralized systems and other top- K ranking algorithms for P2P networks shows the features of the proposed approach. Copyright © 2006 John Wiley & Sons, Ltd. [source]

    Anaphylactic Reactions on the Beach: A Cause for Concern?

    Alexander D. Karatzanis MD
    Background The commonest causes of anaphylaxis include hymenoptera bites, high-risk food, exercise, and jellyfish bites and may often be encountered on the beach. Therefore, millions of visitors at popular touristic locations are exposed to increased risk of anaphylactic reactions every year. At least 35 cases of acute allergic reactions requiring medical attention took place on the beaches of Crete, Greece during the previous summer. Objective To evaluate the level of training of lifeguards working on the beaches of the island of Crete, Greece, with regard to emergency management of anaphylaxis as well as to assess the sufficiency of medical equipment that lifeguards possess to treat an anaphylactic reaction. Methods A questionnaire was prepared by the authors and administered to 50 lifeguards working on various beaches of Crete. Queries included the definition of anaphylaxis, proper medical treatment, and the existence or not and composition of an emergency kit with regard to the management of acute allergic reactions. Results Our series consisted of 50 lifeguards, 39 (78%) male and 11 female (22%). Although 41 (80%) lifeguards were aware of an acceptable definition of anaphylaxis, no one knew that epinephrine is the first-choice treatment, and 32 (60%) lifeguards replied that steroids should be used for emergency treatment. Additionally, no one possessed an emergency kit that would qualify for management of acute allergic reactions. Conclusions The beach should be considered as a high-risk place for the appearance of anaphylactic reactions. Lifeguards who would be the first trained personnel to encounter this condition should be sufficiently trained and equipped for emergency treatment. Our department is currently introducing a training program to local authorities for the proper training and equipping of lifeguards in the island of Crete. [source]

    An Analysis of ASX Price Queries

    Alastair Marsden
    This study examines ,no news' responses to stock price queries issued by the Australian Stock Exchange (ASX). We find strong evidence that the pre-query changes in price are driven by informed traders rather than by speculators. First, there is only a partial reversion in prices following a ,no news' response by a company in receipt of a price query. Second, the adverse selection component of market spreads rise during the immediate pre-query period and then decline following the company response. Last, the mean level of institutional shareholder ownership increases in the period immediately prior to an ASX query of a price increase. [source]


    Manabu Tauchi
    When one tries to use the Web as a dictionary or encyclopedia, entering some single term into a search engine, the highly ranked pages in the result can include irrelevant or useless sites. The problem is that single-term queries, if taken literally, underspecify the type of page the user wants. For such problems automatic query expansion, also known as pseudo-feedback, is often effective. In this method the top n documents returned by an initial retrieval are used to provide terms for a second retrieval. This paper contributes, first, new normalization techniques for query expansion, and second, a new way of computing the similarity between an expanded query and a document, the "local relevance density" metric, which complements the standard vector product metric. Both of these techniques are shown to be useful for single-term queries, in Japanese, in experiments done over the World Wide Web in early 2001. [source]

    Real-time navigating crowds: scalable simulation and rendering

    Julien Pettré
    Abstract This paper introduces a framework for real-time simulation and rendering of crowds navigating in a virtual environment. The solution first consists in a specific environment preprocessing technique giving rise to navigation graphs, which are then used by the navigation and simulation tasks. Second, navigation planning interactively provides various solutions to the user queries, allowing to spread a crowd by individualizing trajectories. A scalable simulation model enables the management of large crowds, while saving computation time for rendering tasks. Pedestrian graphical models are divided into three rendering fidelities ranging from billboards to dynamic meshes, allowing close-up views of detailed digital actors with a large variety of locomotion animations. Examples illustrate our method in several environments with crowds of up to 35,000 pedestrians with real-time performance. Copyright © 2006 John Wiley & Sons, Ltd. [source]

    CHC++: Coherent Hierarchical Culling Revisited

    Oliver Mattausch
    Abstract We present a new algorithm for efficient occlusion culling using hardware occlusion queries. The algorithm significantly improves on previous techniques by making better use of temporal and spatial coherence of visibility. This is achieved by using adaptive visibility prediction and query batching. As a result of the new optimizations the number of issued occlusion queries and the number of rendering state changes are significantly reduced. We also propose a simple method for determining tighter bounding volumes for occlusion queries and a method which further reduces the pipeline stalls. The proposed method provides up to an order of magnitude speedup over the previous state of the art. The new technique is simple to implement, does not rely on hardware calibration and integrates well with modern game engines. [source]

    Freeform Shape Representations for Efficient Geometry Processing

    Leif Kobbelt
    The most important concepts for the handling and storage of freeform shapes in geometry processing applications are parametric representations and volumetric representations. Both have their specific advantages and drawbacks. While the algebraic complexity of volumetric representations is independent from the shape complexity, the domain of a parametric representation usually has to have the same structure as the surface itself (which sometimes makes it necessary to update the domain when the surface is modified). On the other hand, the topology of a parametrically defined surface can be controlled explicitly while in a volumetric representation, the surface topology can change accidentally during deformation. A volumetric representation reduces distance queries or inside/outside tests to mere function evaluations but the geodesic neighborhood relation between surface points is difficult to resolve. As a consequence, it seems promising to combine parametric and volumetric representations to effectively exploit both advantages. In this talk, a number of projects are presented and discussed in which such a combination leads to efficient and numerically stable algorithms for the solution of various geometry processing tasks. Applications include global error control for mesh decimation and smoothing, topology control for level-set surfaces, and shape modeling with unstructured point clouds. [source]

    Progressive Hulls for Intersection Applications

    Nikos Platis
    Abstract Progressive meshes are an established tool for triangle mesh simplification. By suitably adapting the simplification process, progressive hulls can be generated which enclose the original mesh in gradually simpler, nested meshes. We couple progressive hulls with a selective refinement framework and use them in applications involving intersection queries on the mesh. We demonstrate that selectively refinable progressive hulls considerably speed up intersection queries by efficiently locating intersection points on the mesh. Concerning the progressive hull construction, we propose a new formula for assigning edge collapse priorities that significantly accelerates the simplification process, and enhance the existing algorithm with several conditions aimed at producing higher quality hulls. Using progressive hulls has the added advantage that they can be used instead of the enclosed object when a lower resolution of display can be tolerated, thus speeding up the rendering process. ACM CSS: I.3.3 Computer Graphics,Picture/Image Generation, I.3.5 Computer Graphics,Computational Geometry and Object Modeling, I.3.7 Computer Graphics,Three-Dimensional Graphics and Realism [source]

    Deferred, Self-Organizing BSP Trees

    Sigal Ar
    Abstract bsptrees and KD trees are fundamental data structures for collision detection in walkthrough environments. A basic issue in the construction of these hierarchical data structures is the choice of cutting planes. Rather than base these choices solely on the properties of the scene, we propose using information about how the tree is used in order to determine its structure. We demonstrate how this leads to the creation ofbsptrees that are small, do not require much preprocessing time, and respond very efficiently to sequences of collision queries. Categories and Subject Descriptors (according to ACM CCS): I.3.5 [Computer Graphics]: Computational Geometry and Object Modeling I.3.6 [Computer Graphics]: Graphics data structures and data types, Interaction techniques I.3.7 [Computer Graphics]: Virtual reality [source]

    Sortal Structures: Supporting Representational Flexibility for Building Domain Processes

    Rudi Stouffs
    The approach is constructive, based on a part relation on elements within a sort, which enables the recognition of emergent information. The use of data functions as a sort provides for the embedding of data queries within a representational structure. We discuss the application of sorts to supporting alternative data views, illustrating this through a case study in building construction. [source]

    Multiversion concurrency control for the generalized search tree

    Walter Binder
    Abstract Many read-intensive systems where fast access to data is more important than the rate at which data can change make use of multidimensional index structures, like the generalized search tree (GiST). Although in these systems the indexed data are rarely updated and read access is highly concurrent, the existing concurrency control mechanisms for multidimensional index structures are based on locking techniques, which cause significant overhead. In this article we present the multiversion-GiST (MVGiST), an in-memory mechanism that extends the GiST with multiversion concurrency control. The MVGiST enables lock-free read access and ensures a consistent view of the index structure throughout a reader's series of queries, by creating lightweight, read-only versions of the GiST that share unchanging nodes among themselves. An example of a system with high read to write ratio, where providing wait-free queries is of utmost importance, is a large-scale directory that indexes web services according to their input and output parameters. A performance evaluation shows that for low update rates, the MVGiST significantly improves scalability w.r.t. the number of concurrent read accesses when compared with a traditional, locking-based concurrency control mechanism. We propose a technique to control memory consumption and confirm through our evaluation that the MVGiST efficiently manages memory. Copyright © 2009 John Wiley & Sons, Ltd. [source]

    Special Issue: The First Provenance Challenge

    Luc Moreau
    The first Provenance Challenge was set up in order to provide a forum for the community to understand the capabilities of different provenance systems and the expressiveness of their provenance representations. To this end, a functional magnetic resonance imaging workflow was defined, which participants had to either simulate or run in order to produce some provenance representation, from which a set of identified queries had to be implemented and executed. Sixteen teams responded to the challenge, and submitted their inputs. In this paper, we present the challenge workflow and queries, and summarize the participants' contributions. Copyright © 2007 John Wiley & Sons, Ltd. [source]

    Automatic capture and efficient storage of e-Science experiment provenance

    Roger S. Barga
    Abstract For the first provenance challenge, we introduce a layered model to represent workflow provenance that allows navigation from an abstract model of the experiment to instance data collected during a specific experiment run. We outline modest extensions to a commercial workflow engine so it will automatically capture provenance at workflow runtime. We also present an approach to store this provenance data in a relational database. Finally, we demonstrate how core provenance queries in the challenge can be expressed in SQL and discuss the merits of our layered representation. Copyright © 2007 John Wiley & Sons, Ltd. [source]

    Distributed end-host multicast algorithms for the Knowledge Grid

    Wanqing Tu
    Abstract The Knowledge Grid built on top of the peer-to-peer (P2P) network has been studied to implement scalable, available and sematic-based querying. In order to improve the efficiency and scalability of querying, this paper studies the problem of multicasting queries in the Knowledge Grid. An m -dimensional irregular mesh is a popular overlay topology of P2P networks. We present a set of novel distributed algorithms on top of an m -dimensional irregular mesh overlay for the short delay and low network resource consumption end-host multicast services. Our end-host multicast fully utilizes the advantages of an m -dimensional mesh to construct a two-layer architecture. Compared to previous approaches, the novelty and contribution here are: (1) cluster formation that partitions the group members into clusters in the lower layer where cluster consists of a small number of members; (2) cluster core selection that searches a core with the minimum sum of overlay hops to all other cluster members for each cluster; (3) weighted shortest path tree construction that guarantees the minimum number of shortest paths to be occupied by the multicast traffic; (4) distributed multicast routing that directs the multicast messages to be efficiently distributed along the two-layer multicast architecture in parallel, without a global control; the routing scheme enables the packets to be transmitted to the remote end hosts within short delays through some common shortest paths; and (5) multicast path maintenance that restores the normal communication once the membership alteration appears. Simulation results show that our end-host multicast can distributively achieve a shorter delay and lower network resource consumption multicast services as compared with some well-known end-host multicast systems. Copyright © 2006 John Wiley & Sons, Ltd. [source]

    Using semantic links to support top- K join queries in peer-to-peer networks

    Jie Liu
    Abstract An important issue raised in peer-to-peer (P2P) applications is how to accurately and efficiently retrieve a set of K best matching data objects from different sources while minimizing the number of objects that have to be accessed. The proposed solution is to organize peers by a semantic link network representing the semantic relationships between peers' data schemas. Queries are only routed to semantically relevant peers. A pruning-based local top- K ranking approach is proposed to reduce the transmitted data by pruning tuples that cannot produce the desired join results with a rank value at least equal to the lowest rank value generated. Experiments evaluate its performance in terms of the number of transmitted tuples and the miss rate. Comparison with the traditional threshold algorithm for centralized systems and other top- K ranking algorithms for P2P networks shows the features of the proposed approach. Copyright © 2006 John Wiley & Sons, Ltd. [source]

    Effect of redundancy on the mean time to failure of wireless sensor networks

    Anh Phan Speer
    Abstract In data-driven wireless sensor networks (WSNs), the system must perform data sensing and retrieval and possibly aggregate data as a response at runtime. As a WSN is often deployed unattended in areas where replacements of failed sensors are difficult, energy conservation is of primary concern. While the use of redundancy is desirable in terms of satisfying user queries to cope with sensor and transmission faults, it may adversely shorten the lifetime of the WSN, as more sensor nodes will have to be used to answer queries, causing the energy of the system to drain quickly. In this paper, we analyze the effect of redundancy on the mean time to failure (MTTF) of a WSN in terms of the number of queries the system is able to answer correctly before it fails due to either sensor/transmission faults or energy depletion. In particular, we analyze the effect of redundancy on the MTTF of cluster-structured WSNs for energy conservations. We show that a tradeoff exists between redundancy and MTTF. Furthermore, an optimal redundancy level exists such that the MTTF of the system is maximized. Copyright © 2007 John Wiley & Sons, Ltd. [source]

    Measuring and modelling the performance of a parallel ODMG compliant object database server

    Sandra de F. Mendes Sampaio
    Abstract Object database management systems (ODBMSs) are now established as the database management technology of choice for a range of challenging data intensive applications. Furthermore, the applications associated with object databases typically have stringent performance requirements, and some are associated with very large data sets. An important feature for the performance of object databases is the speed at which relationships can be explored. In queries, this depends on the effectiveness of different join algorithms into which queries that follow relationships can be compiled. This paper presents a performance evaluation of the Polar parallel object database system, focusing in particular on the performance of parallel join algorithms. Polar is a parallel, shared-nothing implementation of the Object Database Management Group (ODMG) standard for object databases. The paper presents an empirical evaluation of queries expressed in the ODMG Query Language (OQL), as well as a cost model for the parallel algebra that is used to evaluate OQL queries. The cost model is validated against the empirical results for a collection of queries using four different join algorithms, one that is value based and three that are pointer based. Copyright © 2005 John Wiley & Sons, Ltd. [source]

    Centennial odysseys: longest way round

    CRITICAL QUARTERLY, Issue 1-2 2005
    Michael Wood
    This essay explores the questions about the writing of fiction and the use of metaphor posed by J. M. Coetzee's 2003 work Elizabeth Costello, and finds an answer to these eloquent and disturbing queries in Mr Bloom's reflections on the beach and in the cemetery, instances of Joyce's acceptance of the radical presence of the figurative at the heart of the real. [source]

    Pulse pressure and mortality in hypertensive type 2 diabetic patients.

    A cohort study
    Abstract Hypothesis Hypertension is a well-known cardiovascular risk factor in type 2 diabetic patients. It has been suggested that pulse pressure (PP) could be an independent cardiovascular risk factor in the general population, particularly in the elderly. An association between office PP and cardiovascular mortality has been previously reported in diabetic patients, while the relationship between ambulatory measurements of PP and all-cause mortality has not been assessed so far. Aim To assess the relationship between ambulatory PP and all-cause mortality in diabetic patients with hypertension. Methods A cohort study was performed on a consecutive series of 435 diabetic outpatients. All patients underwent office blood pressure measurement (OBP) and 24-h ambulatory blood pressure monitoring (ABPM). Mortality was assessed through queries at the Registry Offices of the city of residence for each patient. Mean follow-up was 3.8 ± 1.2 years. Results Fifty-eight patients (13.3%) died during the follow-up. Mortality was significantly (p < 0.05) higher in patients in the highest quartile and lower in patients in the lowest quartile, when compared to the intermediate quartiles, both for office and ABPM-PP. In a multivariate analysis, after adjustment for numerous variables (including current hypoglycaemic, antihypertensive statin and aspirin treatment), mortality was increased by 3.1 and 5.3% for each incremental mmHg of office PP (p < 0.05) and ABPM-PP (p < 0.001) respectively. Conclusions High PP, assessed through office measurement or ABPM, was associated with increased mortality in hypertensive type 2 diabetic patients. In our sample, PP assessed with ABPM is a better predictor of mortality than office PP. Copyright © 2005 John Wiley & Sons, Ltd. [source]

    Craving: what can be done to bring the insights of neuroscience, behavioral science and clinical science into synchrony

    ADDICTION, Issue 8s2 2000
    Roger E. Meyer
    Alcohol self-administration behavior is the common thread that is necessary to bring the insights of neuroscience, behavioral science and clinical science into synchrony around the concept of craving. Animal models should address the molecular and cellular changes that take place in behaviorally relevant brain regions of rats consequent to chronic self-administration of ethanol. Animal models can focus on the biology of the anticipatory state in alcohol preferring/consuming rats, as well as studies of the effects of possible medications on this state in the animal model, on actual alcohol consuming behavior, and on the residual effects of chronic alcohol on the non-human mammalian brain. In human studies of craving, cue-reactivity in the absence of the opportunity to drink alcohol does not have the same salience as cue-reactivity in which drinking is possible. Moreover, actual drinking behavior serves to validate self-reports of craving. Studies of limited alcohol self-administration in the laboratory are an essential element in screening new medications for the treatment of alcoholism. Studies to date suggest no adverse reaction to the participation of alcoholic subjects in limited alcohol self-administration studies, but the research community should continue to monitor carefully the outcomes of alcohol-dependent subjects who participate in this type of research, and efforts should always be made to encourage these subjects to enter active treatment. In outpatient clinical trials of new treatments for alcoholism, the assessment of craving should include queries regarding symptoms and signs of protracted abstinence such as sleep disturbances, as well as questions regarding situational craving. Field observations of alcoholics in their favorite drinking environments would contribute greatly to our understanding of the real-world phenomenology of craving. [source]

    Variation in Institutional Review Board Responses to a Standard Protocol for a Multicenter Clinical Trial

    Thomas O. Stair MD
    Abstract. Multicenter clinical trials require approval by multiple local institutional review boards (IRBs). The Multicenter Airway Research Collaboration mailed a clinical trial protocol to its U.S. investigators and 44 IRBs ultimately reviewed it. Objective: To describe IRB responses to one standard protocol and thereby gain insight into the advantages and disadvantages of local IRB review. Methods: Two surveys were mailed to participants, with telephone follow-up of nonrespondents. Survey 1 was mailed to 82 investigators across North America. Survey 2 was mailed to investigators from 44 medical centers in 17 U.S. states. Survey 1 asked about each investigator's local IRB (e.g., frequency of meetings, membership), whereas survey 2 asked about IRB queries and concerns related to the submitted clinical trial. Results: Both surveys had 100% response rate. Investigators submitted applications a median of 58 days (interquartile range [IQR], 40-83) after receipt of the protocol, and IRB approval took an additional 38 days (IQR, 26-62). Although eight applications were approved with little or no changes, IRBs requested an average of 3.5 changes per site. Changes involved study logistics and supervision for 45%, the research process for 43%, and the consent form for 91%. Despite these numerous requests, all eventually approved the basic protocol, including inclusion criteria, intervention, and data collection. Conclusions: The IRBs showed extreme variability in their initial responses to a standard protocol, but ultimately all gave approval. Almost all IRBs changed the consent form. A national, multicenter IRB process might streamline ethical review and warrants further consideration. [source]

    A model of an information retrieval system with unbalanced fuzzy linguistic information

    Enrique Herrera-Viedma
    Most information retrieval systems based on linguistic approaches use symmetrically and uniformly distributed linguistic term sets to express the weights of queries and the relevance degrees of documents. However, to improve the system,user interaction, it seems more adequate to express these linguistic weights and degrees by means of unbalanced linguistic scales, that is, linguistic term sets with different discrimination levels on both sides of the middle linguistic term. In this contribution we present an information retrieval system that accepts weighted queries whose weights are expressed using unbalanced linguistic term sets. Then, the system provides the retrieved documents classified in linguistic relevance classes assessed on unbalanced linguistic term sets. To do so, we propose a methodology to manage unbalanced linguistic information and we use the linguistic 2-tuple model as the representation base of the unbalanced linguistic information. Additionally, the linguistic 2-tuple model allows us to increase the number of relevance classes in the output and also to improve the performance of the information retrieval system. © 2007 Wiley Periodicals, Inc. Int J Int Syst 22: 1197,1214, 2007. [source]

    About yes/no queries against possibilistic databases

    Patrick Bosc
    This article is concerned with the handling of imprecise information in databases. The need for dealing with imprecise data is more and more acknowledged in order to cope with real data, even if commercial systems are most of the time unable to manage them. Here, the possibilistic setting is taken into consideration because it is less demanding than the probabilistic one. Then, any imprecise piece of information is modeled as a possibility distribution intended for constraining the more or less acceptable values. Such a possibilistic database has a natural interpretation in terms of a set of regular databases, which provides the basic gateway to interpret queries. However, if this approach is sound, it is not realistic, and it is necessary to consider restricted queries for which a calculus grounded on the possibilistic database, that is, where the operators work directly on possibilistic relations, is feasible. Extended yes/no queries are dealt with here, where their general form is: "to what extent is it possible and certain that tuple t (given) belongs to the answer to Q," where Q is an algebraic relational query. A strategy for processing such queries efficiently is proposed under some assumptions as to the operators appearing in Q. © 2007 Wiley Periodicals, Inc. Int J Int Syst 22: 691,721, 2007. [source]

    Flexible querying of semistructured data: A fuzzy-set-based approach

    Martine De Calmčs
    This article provides a general discussion about how flexible querying can be applied to semistructured data (SSD). We adapt flexible querying ideas, already used for classically structured databases, to XQuery-like querying of SSD for managing users' priority and preferences, but also for tackling with the variability of SSD underlying structures. Indeed flexible querying seems to be still more useful for SSD than for classical databases, because of the potential structural heterogeneity of the former. Fuzzy sets are useful for expressing flexible requirements on attribute values and for estimating the degree of similarity of tags, or attribute labels, with elements present in the request. Priorities are introduced in the request for specifying the relative importance of elementary requirements in terms of their semantic contents, but also preferences about the location of information in the structure. The evaluation of the queries uses a qualitative scale with a finite number of levels, and retrieved pieces of SSD are rank-ordered using a lexicographic vector procedure. Illustrative examples are provided. © 2007 Wiley Periodicals, Inc. Int J Int Syst 22: 723,737, 2007. [source]

    Using clustering methods to improve ontology-based query term disambiguation

    Ernesto William De Luca
    In this article we describe results of our research on the disambiguation of user queries using ontologies for categorization. We present an approach to cluster search results by using classes or "Sense Folders" (prototype categories) derived from the concepts of an assigned ontology, in our case WordNet. Using the semantic relations provided from such a resource, we can assign categories to prior, not annotated documents. The disambiguation of query terms in documents with respect to a user-specific ontology is an important issue in order to improve the retrieval performance for the user. Furthermore, we show that a clustering process can enhance the semantic classification of documents, and we discuss how this clustering process can be further enhanced using only the most descriptive classes of the ontology. © 2006 Wiley Periodicals, Inc. Int J Int Syst 21: 693,709, 2006. [source]

    Tuning the matching function for a threshold weighting semantics in a linguistic information retrieval system

    E. Herrera-Viedma
    Information retrieval is an activity that attempts to produce documents that better fulfill user information needs. To achieve this activity an information retrieval system uses matching functions that specify the degree of relevance of a document with respect to a user query. Assuming linguistic-weighted queries we present a new linguistic matching function for a threshold weighting semantics that is defined using a 2-tuple fuzzy linguistic approach (Herrera F, Martínez L. IEEE Trans Fuzzy Syst 2000;8:746,752). This new 2-tuple linguistic matching function can be interpreted as a tuning of that defined in "Modelling the Retrieval Process for an Information Retrieval System Using an Ordinal Fuzzy Linguistic Approach" (Herrera-Viedma E. J Am Soc Inform Sci Technol 2001;52:460,475). We show that it simplifies the processes of computing in the retrieval activity, avoids the loss of precision in final results, and, consequently, can help to improve the users' satisfaction. © 2005 Wiley Periodicals, Inc. Int J Int Syst 20: 921,937, 2005. [source]

    Answers to queries concerning uncertain and imprecise information in fuzzy relational databases

    Nan-Chen Hsieh
    A model of an extended fuzzy relational database was proposed to accommodate uncertain and imprecise information. We use two supplementary measurements, satisfactory degree and extra degree, for determining the quality of answers to Select-Project-Join (SPJ) queries. The method of measurement determines how much satisfactory information is provided and how much truth information is required for a query. The answers to the query thus contain sure answers and maybe answers. The core of this study is the detailed discussion on the quality of answers in an extended fuzzy relation to query processing. © 2005 Wiley Periodicals, Inc. Int J Int Syst 20: 647,668, 2005. [source]

    Databases for interval probabilities

    Wenzhong Zhao
    We present a database framework for the efficient storage and manipulation of interval probability distributions and their associated information. Although work on interval probabilities and on probabilistic databases has appeared before, ours is the first to combine these into a coherent and mathematically sound framework including both standard relational queries and queries based on probability theory. In particular, our query algebra allows users not only to query existing interval probability distributions, but also to construct new ones by means of conditionalization and marginalization, as well as other more common database operations. © 2004 Wiley Periodicals, Inc. Int J Int Syst 19: 789,815, 2004. [source]

    Reducing admission times in the endoscopy unit

    Deborah Dobree-Carey RGN
    Pre-procedural admission of outpatients to a day-case endoscopy facility is time-consuming. Collecting and recording routine but necessary information distracts nurses from spending time that could be used to counsel patients. This study assessed whether patients can record some pre-procedural details and whether such self-recording quickens nurse admission times. A new admission document was devised and posted to patients. Patients completed personal/administrative details and information about drugs and allergies and brought the document with them when attending for outpatient endoscopy. Endoscopy nurses anonymously timed 100 admissions, 50 using the new admission form and 50 using the old admission form. Overall, the median (range) time to admit using the old form was 6 (3,15.5) min. Using the new form, the median time to admit was lower at 4 (0.5,10) min. No patient completing the new form reported any particular difficulties. An admission document that patients partially complete at home leads to a faster pre-procedural admission in the endoscopy unit. This allows more nursing time to discuss patients' anxieties and answer patient queries, helps to prevent delays and facilitates increased capacity in the endoscopy unit. [source]

    Money with a Mean Streak?

    Foreign Economic Penetration, Government Respect for Human Rights in Developing Countries
    This study examines the relationship between foreign economic capital and the level of government respect for two types of human rights in developing countries. Two opposing schools of thought offer explanations as to what this relationship might be like. According to the liberal neoclassical school, the acceptance of liberal economic doctrine will provide positive political benefits to developing countries. The "dependency" school, on the other hand, argues that because ties between core and periphery elites give governments in developing nations an incentive to repress, human rights conditions will worsen as foreign economic penetration increases. The results of previous empirical queries into this matter have been mixed. In contrast to most studies, we focus on a broader measure of foreign economic capital, including foreign direct investment, portfolio investment, debt, and official development assistance. Using ordered logit analysis on a cross-national sample of forty-three developing countries from 1981 to 1995, we discover systematic evidence of an association between foreign economic penetration and government respect for two types of human rights, physical integrity rights and political rights and civil liberties. Of particular interest is the finding that both foreign direct investment and portfolio investment are reliably associated with increased government respect for human rights. [source]