WorldWideScience

Sample records for anonymized ons queries

  1. Comments on ``Anonymous Reviews'' An Editor's View of Anonymous Reviews

    Science.gov (United States)

    Goff, John A.

    I have read with great interest the recent Forum commentaries in Eos by Myrl Beck, Charles Robinove, Robert Criss, and Anne Hofmeister regarding anonymous reviews. I heartily support their position that anonymous reviews should be avoided. I have not written an anonymous review in ages (and regret the few that I did), and have always appreciated and respected greatly anyone who signs a critical review of one of my own papers. However, I would like to add some perspective from the editorial standpoint. I have served as JGR associate editor for 3 years (never anonymously!), and as Eos editor for seismology and tectonophysics for 4. Over the years, I have rejected a fair number of papers, most of those based on anonymous reviews (fortunately, none of the above commentators was one of them). The vast majority of anonymous reviews I received were well considered. While I would wish that all reviews were signed, I don't think we can summarily dismiss the fear that many would have of enmity and reprisal over a critical review. Some of these fears are likely justified. On more than one occasion, have I witnessed overly aggressive responses on the part of authors to anonymous reviews that I considered to be entirely fair and constructive in their criticisms. I do think we need to do all we can to discourage anonymous reviews, but it will be difficult to completely remove that choice from the process.

  2. On Backward-Style Anonymity Verification

    Science.gov (United States)

    Kawabe, Yoshinobu; Mano, Ken; Sakurada, Hideki; Tsukada, Yasuyuki

    Many Internet services and protocols should guarantee anonymity; for example, an electronic voting system should guarantee to prevent the disclosure of who voted for which candidate. To prove trace anonymity, which is an extension of the formulation of anonymity by Schneider and Sidiropoulos, this paper presents an inductive method based on backward anonymous simulations. We show that the existence of an image-finite backward anonymous simulation implies trace anonymity. We also demonstrate the anonymity verification of an e-voting protocol (the FOO protocol) with our backward anonymous simulation technique. When proving the trace anonymity, this paper employs a computer-assisted verification tool based on a theorem prover.

  3. Querying on Federated Sensor Networks

    Directory of Open Access Journals (Sweden)

    Zuhal Can

    2016-09-01

    Full Text Available A Federated Sensor Network (FSN is a network of geographically distributed Wireless Sensor Networks (WSNs called islands. For querying on an FSN, we introduce the Layered Federated Sensor Network (L-FSN Protocol. For layered management, L-FSN provides communication among islands by its inter-island querying protocol by which a query packet routing path is determined according to some path selection policies. L-FSN allows autonomous management of each island by island-specific intra-island querying protocols that can be selected according to island properties. We evaluate the applicability of L-FSN and compare the L-FSN protocol with various querying protocols running on the flat federation model. Flat federation is a method to federate islands by running a single querying protocol on an entire FSN without distinguishing communication among and within islands. For flat federation, we select a querying protocol from geometrical, hierarchical cluster-based, hash-based, and tree-based WSN querying protocol categories. We found that a layered federation of islands by L-FSN increases the querying performance with respect to energy-efficiency, query resolving distance, and query resolving latency. Moreover, L-FSN’s flexibility of choosing intra-island querying protocols regarding the island size brings advantages on energy-efficiency and query resolving latency.

  4. 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

  5. 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...

  6. 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...

  7. Anonymous communication networks protecting privacy on the web

    CERN Document Server

    Peng, Kun

    2014-01-01

    In today's interactive network environment, where various types of organizations are eager to monitor and track Internet use, anonymity is one of the most powerful resources available to counterbalance the threat of unknown spectators and to ensure Internet privacy.Addressing the demand for authoritative information on anonymous Internet usage, Anonymous Communication Networks: Protecting Privacy on the Web examines anonymous communication networks as a solution to Internet privacy concerns. It explains how anonymous communication networks make it possible for participants to communicate with

  8. An Extensive Study on Data Anonymization Algorithms Based on K-Anonymity

    Science.gov (United States)

    Simi, Ms. M. S.; Sankara Nayaki, Mrs. K.; Sudheep Elayidom, M., Dr.

    2017-08-01

    For business and research oriented works engaging Data Analysis and Cloud services needing qualitative data, many organizations release huge microdata. It excludes an individual’s explicit identity marks like name, address and comprises of specific information like DOB, Pin-code, sex, marital status, which can be combined with other public data to recognize a person. This implication attack can be manipulated to acquire any sensitive information from social network platform, thereby putting the privacy of a person in grave danger. To prevent such attacks by modifying microdata, K-anonymization is used. With potentially increasing data, the effective method to anonymize it stands challenging. After series of trails and systematic comparison, in this paper, we propose three best algorithms along with its efficiency and effectiveness. Studies help researchers to identify the relationship between the values of k, degree of anonymization, choosing a quasi-identifier and focus on execution time.

  9. 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.

  10. Assessing Anonymous Communication on the Internet: Policy Deliberations.

    Science.gov (United States)

    Kling, Rob; Lee, Yaching; Frankel, Mark S.; Teich, Al

    1999-01-01

    Examines the social character of anonymous online communication and the ways that anonymous communication has played important roles for professionals such as journalists and the police. Explains some of the new technological supports for anonymous communication on the Internet. Discusses some of the nuances behind the controversies and policy…

  11. 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

  12. 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.

  13. 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.

  14. Digital anonymity on the internet : new rules for anonymous electronic transactions? an exploration of the private law implications of digital anonymity

    NARCIS (Netherlands)

    Grijpink, J.H.A.M.; Prins, C.

    2001-01-01

    This article sets out the most important conclusions of the first stage of a study into the dimensions of digital anonymity. It is intended to set out the problem, make people aware of the intricacies of the problem and thus stimulate the debate on useful legal structures for anonymity. The

  15. What Does Anonymization Mean? DataSHIELD and the Need for Consensus on Anonymization Terminology.

    Science.gov (United States)

    Wallace, Susan E

    2016-06-01

    Anonymization is a recognized process by which identifiers can be removed from identifiable data to protect an individual's confidentiality and is used as a standard practice when sharing data in biomedical research. However, a plethora of terms, such as coding, pseudonymization, unlinked, and deidentified, have been and continue to be used, leading to confusion and uncertainty. This article shows that this is a historic problem and argues that such continuing uncertainty regarding the levels of protection given to data risks damaging initiatives designed to assist researchers conducting cross-national studies and sharing data internationally. DataSHIELD and the creation of a legal template are used as examples of initiatives that rely on anonymization, but where the inconsistency in terminology could hinder progress. More broadly, this article argues that there is a real possibility that there could be possible damage to the public's trust in research and the institutions that carry it out by relying on vague notions of the anonymization process. Research participants whose lack of clear understanding of the research process is compensated for by trusting those carrying out the research may have that trust damaged if the level of protection given to their data does not match their expectations. One step toward ensuring understanding between parties would be consistent use of clearly defined terminology used internationally, so that all those involved are clear on the level of identifiability of any particular set of data and, therefore, how that data can be accessed and shared.

  16. System for Anonymous Data Collection Based on Group Signature Scheme

    Directory of Open Access Journals (Sweden)

    David Troják

    2016-01-01

    Full Text Available This paper deals with an anonymous data collection in the Internet of Things (IoT. the privacy and anonymity of the data source is important for many IoT applications, such as in agriculture, health, and automotive. the proposed data‑collection system provides anonymity for the data sources by applying a cooperation group scheme. the group scheme also provides a low power consumption. the system is built upon the Tor (The Onion Router anonymous network, which is a part of the Internet darknet. the proposed system was designed for the Android devices on the client side and for Java environment on the server side. We evaluated the anonymous data collection in a real‑use scenario that covers selected data acquisition (e.g. signal strength from smartphones triggered by their geographical location change. the results show that the proposed system provides the sufficient data source anonymity, an effective revocation, a low computational cost and a low overhead.

  17. Heuristic query optimization for query multiple table and multiple clausa on mobile finance application

    Science.gov (United States)

    Indrayana, I. N. E.; P, N. M. Wirasyanti D.; Sudiartha, I. KG

    2018-01-01

    Mobile application allow many users to access data from the application without being limited to space, space and time. Over time the data population of this application will increase. Data access time will cause problems if the data record has reached tens of thousands to millions of records.The objective of this research is to maintain the performance of data execution for large data records. One effort to maintain data access time performance is to apply query optimization method. The optimization used in this research is query heuristic optimization method. The built application is a mobile-based financial application using MySQL database with stored procedure therein. This application is used by more than one business entity in one database, thus enabling rapid data growth. In this stored procedure there is an optimized query using heuristic method. Query optimization is performed on a “Select” query that involves more than one table with multiple clausa. Evaluation is done by calculating the average access time using optimized and unoptimized queries. Access time calculation is also performed on the increase of population data in the database. The evaluation results shown the time of data execution with query heuristic optimization relatively faster than data execution time without using query optimization.

  18. On the formulation of performant sparql queries

    NARCIS (Netherlands)

    Loizou, A.; Angles, R.; Groth, P.T.

    2014-01-01

    Abstract The combination of the flexibility of RDF and the expressiveness of SPARQL provides a powerful mechanism to model, integrate and query data. However, these properties also mean that it is nontrivial to write performant SPARQL queries. Indeed, it is quite easy to create queries that tax even

  19. Location Prediction Based on Transition Probability Matrices Constructing from Sequential Rules for Spatial-Temporal K-Anonymity Dataset

    Science.gov (United States)

    Liu, Zhao; Zhu, Yunhong; Wu, Chenxue

    2016-01-01

    Spatial-temporal k-anonymity has become a mainstream approach among techniques for protection of users’ privacy in location-based services (LBS) applications, and has been applied to several variants such as LBS snapshot queries and continuous queries. Analyzing large-scale spatial-temporal anonymity sets may benefit several LBS applications. In this paper, we propose two location prediction methods based on transition probability matrices constructing from sequential rules for spatial-temporal k-anonymity dataset. First, we define single-step sequential rules mined from sequential spatial-temporal k-anonymity datasets generated from continuous LBS queries for multiple users. We then construct transition probability matrices from mined single-step sequential rules, and normalize the transition probabilities in the transition matrices. Next, we regard a mobility model for an LBS requester as a stationary stochastic process and compute the n-step transition probability matrices by raising the normalized transition probability matrices to the power n. Furthermore, we propose two location prediction methods: rough prediction and accurate prediction. The former achieves the probabilities of arriving at target locations along simple paths those include only current locations, target locations and transition steps. By iteratively combining the probabilities for simple paths with n steps and the probabilities for detailed paths with n-1 steps, the latter method calculates transition probabilities for detailed paths with n steps from current locations to target locations. Finally, we conduct extensive experiments, and correctness and flexibility of our proposed algorithm have been verified. PMID:27508502

  20. Research on Anonymization and De-anonymization in the Bitcoin System

    OpenAIRE

    ShenTu, QingChun; Yu, JianPing

    2015-01-01

    The Bitcoin system is an anonymous, decentralized crypto-currency. There are some deanonymizating techniques to cluster Bitcoin addresses and to map them to users' identifications in the two research directions of Analysis of Transaction Chain (ATC) and Analysis of Bitcoin Protocol and Network (ABPN). Nowadays, there are also some anonymization methods such as coin-mixing and transaction remote release (TRR) to cover the relationship between Bitcoin address and the user. This paper studies an...

  1. 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

  2. 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

  3. 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,

  4. Secure count query on encrypted genomic data.

    Science.gov (United States)

    Hasan, Mohammad Zahidul; Mahdi, Md Safiur Rahman; Sadat, Md Nazmus; Mohammed, Noman

    2018-05-01

    Human genomic information can yield more effective healthcare by guiding medical decisions. Therefore, genomics research is gaining popularity as it can identify potential correlations between a disease and a certain gene, which improves the safety and efficacy of drug treatment and can also develop more effective prevention strategies [1]. To reduce the sampling error and to increase the statistical accuracy of this type of research projects, data from different sources need to be brought together since a single organization does not necessarily possess required amount of data. In this case, data sharing among multiple organizations must satisfy strict policies (for instance, HIPAA and PIPEDA) that have been enforced to regulate privacy-sensitive data sharing. Storage and computation on the shared data can be outsourced to a third party cloud service provider, equipped with enormous storage and computation resources. However, outsourcing data to a third party is associated with a potential risk of privacy violation of the participants, whose genomic sequence or clinical profile is used in these studies. In this article, we propose a method for secure sharing and computation on genomic data in a semi-honest cloud server. In particular, there are two main contributions. Firstly, the proposed method can handle biomedical data containing both genotype and phenotype. Secondly, our proposed index tree scheme reduces the computational overhead significantly for executing secure count query operation. In our proposed method, the confidentiality of shared data is ensured through encryption, while making the entire computation process efficient and scalable for cutting-edge biomedical applications. We evaluated our proposed method in terms of efficiency on a database of Single-Nucleotide Polymorphism (SNP) sequences, and experimental results demonstrate that the execution time for a query of 50 SNPs in a database of 50,000 records is approximately 5 s, where each record

  5. 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...

  6. Can anonymous posters on medical forums be reidentified?

    Science.gov (United States)

    Bobicev, Victoria; Sokolova, Marina; El Emam, Khaled; Jafer, Yasser; Dewar, Brian; Jonker, Elizabeth; Matwin, Stan

    2013-10-03

    Participants in medical forums often reveal personal health information about themselves in their online postings. To feel comfortable revealing sensitive personal health information, some participants may hide their identity by posting anonymously. They can do this by using fake identities, nicknames, or pseudonyms that cannot readily be traced back to them. However, individual writing styles have unique features and it may be possible to determine the true identity of an anonymous user through author attribution analysis. Although there has been previous work on the authorship attribution problem, there has been a dearth of research on automated authorship attribution on medical forums. The focus of the paper is to demonstrate that character-based author attribution works better than word-based methods in medical forums. The goal was to build a system that accurately attributes authorship of messages posted on medical forums. The Authorship Attributor system uses text analysis techniques to crawl medical forums and automatically correlate messages written by the same authors. Authorship Attributor processes unstructured texts regardless of the document type, context, and content. The messages were labeled by nicknames of the forum participants. We evaluated the system's performance through its accuracy on 6000 messages gathered from 2 medical forums on an in vitro fertilization (IVF) support website. Given 2 lists of candidate authors (30 and 50 candidates, respectively), we obtained an F score accuracy in detecting authors of 75% to 80% on messages containing 100 to 150 words on average, and 97.9% on longer messages containing at least 300 words. Authorship can be successfully detected in short free-form messages posted on medical forums. This raises a concern about the meaningfulness of anonymous posting on such medical forums. Authorship attribution tools can be used to warn consumers wishing to post anonymously about the likelihood of their identity being

  7. The influence of anonymous peers on prosocial behavior.

    Directory of Open Access Journals (Sweden)

    Soowon Park

    Full Text Available Peer influence on students' maladaptive behaviors has been well documented; however, the influence on positive development is less acknowledged.The purpose of this study was to examine anonymous peer influence on college students' prosocial behavior, specifically behavior for the improvement of society (i.e., donating money or participating in social campaigns via an experimental approach. The effects of indirect peer influence (IP and direct peer influence (DP on college students' prosocial behavior were examined.A total of 125 college students participated in an online survey and laboratory experiment. Self-reported helping behavior, social concern goals, and empathy were measured by the online survey. In the laboratory experiments, reading of a prosocial paragraph (IP and confederates' prosocial behavior (DP were manipulated. Participation in a signature campaign and money donation for illness were observed. Furthermore, 19 participants among those who donated were asked about their reasons for participating in such prosocial behavior.Prosocial behavior of anonymous peers (confederates exerts a profound influence on college students' participation in a signature campaign and money donation, whereas the reading of a prosocial paragraph has no effect. Furthermore, no participants reported peer influence as a reason for engaging in prosocial behavior.This finding supports and extends recent research examining the positive impacts of anonymous peers on prosocial behavior. Prosocial behavior is not only a foundational and consistent aspect of personality, as previous studies report, but is also highly malleable and unstable in response to immediate situations.

  8. The influence of anonymous peers on prosocial behavior

    Science.gov (United States)

    Shin, Jongho

    2017-01-01

    Background Peer influence on students’ maladaptive behaviors has been well documented; however, the influence on positive development is less acknowledged. Purpose The purpose of this study was to examine anonymous peer influence on college students’ prosocial behavior, specifically behavior for the improvement of society (i.e., donating money or participating in social campaigns) via an experimental approach. The effects of indirect peer influence (IP) and direct peer influence (DP) on college students’ prosocial behavior were examined. Methods A total of 125 college students participated in an online survey and laboratory experiment. Self-reported helping behavior, social concern goals, and empathy were measured by the online survey. In the laboratory experiments, reading of a prosocial paragraph (IP) and confederates’ prosocial behavior (DP) were manipulated. Participation in a signature campaign and money donation for illness were observed. Furthermore, 19 participants among those who donated were asked about their reasons for participating in such prosocial behavior. Results Prosocial behavior of anonymous peers (confederates) exerts a profound influence on college students’ participation in a signature campaign and money donation, whereas the reading of a prosocial paragraph has no effect. Furthermore, no participants reported peer influence as a reason for engaging in prosocial behavior. Conclusion This finding supports and extends recent research examining the positive impacts of anonymous peers on prosocial behavior. Prosocial behavior is not only a foundational and consistent aspect of personality, as previous studies report, but is also highly malleable and unstable in response to immediate situations. PMID:29016612

  9. 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.

  10. 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).

  11. 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...

  12. 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...

  13. 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

  14. Quantum election scheme based on anonymous quantum key distribution

    International Nuclear Information System (INIS)

    Zhou Rui-Rui; Yang Li

    2012-01-01

    An unconditionally secure authority-certified anonymous quantum key distribution scheme using conjugate coding is presented, based on which we construct a quantum election scheme without the help of an entanglement state. We show that this election scheme ensures the completeness, soundness, privacy, eligibility, unreusability, fairness, and verifiability of a large-scale election in which the administrator and counter are semi-honest. This election scheme can work even if there exist loss and errors in quantum channels. In addition, any irregularity in this scheme is sensible. (general)

  15. 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.

  16. 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...

  17. 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....

  18. Query deforestation

    OpenAIRE

    Grust, Torsten; Scholl, Marc H.

    1998-01-01

    The construction of a declarative query engine for a DBMS includes the challenge of compiling algebraic queries into efficient execution plans that can be run on top of the persistent storage. This work pursues the goal of employing foldr-build deforestation for the derivation of efficient streaming programs - programs that do not allocate intermediate data structures to perform their task - from algebraic (combinator) query plans. The query engine is based on the insertion representation of ...

  19. The Effects of Perceived Anonymity on Altruistic Punishment

    Directory of Open Access Journals (Sweden)

    Jared Piazza

    2008-07-01

    Full Text Available Previous studies investigating altruistic punishment have confounded the effects of two independent variables: information transmission (or breach of privacy and personal identification (or breach of anonymity. Here we report findings from a brief study in which participants were asked to respond to a social norm violation (i.e., an anonymous actor had behaved selfishly in an economic game by deciding whether to sacrifice their own endowment to punish this person. A third of the participants were told that their economic decisions would be made known to another player but could not be identified (privacy breach condition, whereas another third were informed that their decision as well as their names would be made known (anonymity breach condition. (The decisions of control participants were completely anonymous and private. Participants also justified their economic decisions and reported their emotional experiences. The results were participants punished most in the privacy and anonymity breach conditions and least in the control condition. These findings have implications for existing evolutionary accounts of altruistic punishment.

  20. 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.

  1. On the Anonymity Risk of Time-Varying User Profiles

    Directory of Open Access Journals (Sweden)

    Silvia Puglisi

    2017-04-01

    Full Text Available Websites and applications use personalisation services to profile their users, collect their patterns and activities and eventually use this data to provide tailored suggestions. User preferences and social interactions are therefore aggregated and analysed. Every time a user publishes a new post or creates a link with another entity, either another user, or some online resource, new information is added to the user profile. Exposing private data does not only reveal information about single users’ preferences, increasing their privacy risk, but can expose more about their network that single actors intended. This mechanism is self-evident in social networks where users receive suggestions based on their friends’ activities. We propose an information-theoretic approach to measure the differential update of the anonymity risk of time-varying user profiles. This expresses how privacy is affected when new content is posted and how much third-party services get to know about the users when a new activity is shared. We use actual Facebook data to show how our model can be applied to a real-world scenario.

  2. 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

  3. Who Goes There? Staying Anonymous on the Internet

    Science.gov (United States)

    Descy, Don E.

    2009-01-01

    Privacy is a thing of the past. Monitoring is everywhere. If one is looking at this online, the author is sure that lots of information has been stored and linked to anyone about that action. Nevertheless, at least people can try to play with "their" minds and surf the web anonymously. In this article, the author discusses ways to try to hide…

  4. Visibility and anonymity effects on attraction and group cohesiveness

    NARCIS (Netherlands)

    Lea, Martin; Spears, Russell; Watt, Susan E.

    2007-01-01

    This study investigated attraction and group cohesiveness under different visibility and anonymity conditions for social categories that differed in their capacity to be visually cued. Using computer-mediated communication in 36 mixed gender (visually cued category) and nationality (non-visually

  5. Web page sorting algorithm based on query keyword distance relation

    Science.gov (United States)

    Yang, Han; Cui, Hong Gang; Tang, Hao

    2017-08-01

    In order to optimize the problem of page sorting, according to the search keywords in the web page in the relationship between the characteristics of the proposed query keywords clustering ideas. And it is converted into the degree of aggregation of the search keywords in the web page. Based on the PageRank algorithm, the clustering degree factor of the query keyword is added to make it possible to participate in the quantitative calculation. This paper proposes an improved algorithm for PageRank based on the distance relation between search keywords. The experimental results show the feasibility and effectiveness of the method.

  6. On a Fuzzy Algebra for Querying Graph Databases

    OpenAIRE

    Pivert , Olivier; Thion , Virginie; Jaudoin , Hélène; Smits , Grégory

    2014-01-01

    International audience; This paper proposes a notion of fuzzy graph database and describes a fuzzy query algebra that makes it possible to handle such database, which may be fuzzy or not, in a flexible way. The algebra, based on fuzzy set theory and the concept of a fuzzy graph, is composed of a set of operators that can be used to express preference queries on fuzzy graph databases. The preferences concern i) the content of the vertices of the graph and ii) the structure of the graph. In a s...

  7. 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.

  8. 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...

  9. On performing semantic queries in small devices

    Science.gov (United States)

    Costea, C.; Petrovan, A.; Neamţ, L.; Chiver, O.

    2016-08-01

    The sensors have a well-defined role in control or monitoring industrial processes; the data given by them can generate valuable information of the trend of the systems to which they belong, but to store a large volume of data and then analysis offline is not always practical. One solution is on-line analysis, preferably as close to the place where data have been generated (edge computing). An increasing amount of data generated by a growing number of devices connected to the Internet resulted in processing data sensors to the edge of the network, in a middle layer where smart entities should interoperate. Diversity of communication technologies outlined the idea of using intermediate devices such as gateways in sensor networks and for this reason the paper examines the functionality of a SPARQL endpoint in the Raspberry Pi device.

  10. 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.

  11. 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.

  12. A New Heuristic Anonymization Technique for Privacy Preserved Datasets Publication on Cloud Computing

    Science.gov (United States)

    Aldeen Yousra, S.; Mazleena, Salleh

    2018-05-01

    Recent advancement in Information and Communication Technologies (ICT) demanded much of cloud services to sharing users’ private data. Data from various organizations are the vital information source for analysis and research. Generally, this sensitive or private data information involves medical, census, voter registration, social network, and customer services. Primary concern of cloud service providers in data publishing is to hide the sensitive information of individuals. One of the cloud services that fulfill the confidentiality concerns is Privacy Preserving Data Mining (PPDM). The PPDM service in Cloud Computing (CC) enables data publishing with minimized distortion and absolute privacy. In this method, datasets are anonymized via generalization to accomplish the privacy requirements. However, the well-known privacy preserving data mining technique called K-anonymity suffers from several limitations. To surmount those shortcomings, I propose a new heuristic anonymization framework for preserving the privacy of sensitive datasets when publishing on cloud. The advantages of K-anonymity, L-diversity and (α, k)-anonymity methods for efficient information utilization and privacy protection are emphasized. Experimental results revealed the superiority and outperformance of the developed technique than K-anonymity, L-diversity, and (α, k)-anonymity measure.

  13. Protecting whistle-blowers: Anonymity on the internet

    International Nuclear Information System (INIS)

    Guinnessy, P.

    1997-01-01

    Even though strict legislation exists in many countries, it appears that the next few years should be a golden opportunity for groups to successfully monitor and publish the activity of the nuclear states, and human right violations through use of the Internet. The reasons for this are: 1. The Internet is becoming widespread even in repressive regimes; 2. Software is available to either hide messages from others or hide the mailers account; 3. Information from sites in other countries can be easily obtained to be read inside repressive regimes from the Internet. In this regard It is suggested the Pugwash or a similar organization should set up either an anonymous account to receive information or maybe use a more heavily protected cyperpunk remailer. Such an ability would hopefully prompt more people to notify treaty violations

  14. On the query reformulation technique for effective MEDLINE document retrieval.

    Science.gov (United States)

    Yoo, Sooyoung; Choi, Jinwook

    2010-10-01

    Improving the retrieval accuracy of MEDLINE documents is still a challenging issue due to low retrieval precision. Focusing on a query expansion technique based on pseudo-relevance feedback (PRF), this paper addresses the problem by systematically examining the effects of expansion term selection and adjustment of the term weights of the expanded query using a set of MEDLINE test documents called OHSUMED. Implementing a baseline information retrieval system based on the Okapi BM25 retrieval model, we compared six well-known term ranking algorithms for useful expansion term selection and then compared traditional term reweighting algorithms with our new variant of the standard Rocchio's feedback formula, which adopts a group-based weighting scheme. Our experimental results on the OHSUMED test collection showed a maximum improvement of 20.2% and 20.4% for mean average precision and recall measures over unexpanded queries when terms were expanded using a co-occurrence analysis-based term ranking algorithm in conjunction with our term reweighting algorithm (p-valueretrieval.

  15. Impact of Anonymity and Identity Deception on Social Media eWOM

    OpenAIRE

    Kapoor , Payal ,; Gunta , Srinivas

    2016-01-01

    Part 4: Information Sharing on Social Media; International audience; Brand-related consumer to consumer communication, eWOM, is taking place in many forms across the social media space. Rules that governed credibility assessment of brand-related communication, WOM, in the Face to Face context may vary on social media, specifically because of anonymity that is afforded on different social media sites. The current study looks closely on the impact of anonymity in typical eWOM behaviour context ...

  16. 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.

  17. To Speak or Not to Speak: Developing Legal Standards for Anonymous Speech on the Internet

    Directory of Open Access Journals (Sweden)

    Tomas A. Lipinski

    2002-01-01

    Full Text Available This paper explores recent developments in the regulation of Internet speech, in specific, injurious or defamatory speech and the impact such speech has on the rights of anonymous speakers to remain anonymous as opposed to having their identity revealed to plaintiffs or other third parties. The paper proceeds in four sections.  First, a brief history of the legal attempts to regulate defamatory Internet speech in the United States is presented. As discussed below this regulation has altered the traditional legal paradigm of responsibility and as a result creates potential problems for the future of anonymous speech on the Internet.  As a result plaintiffs are no longer pursuing litigation against service providers but taking their dispute directly to the anonymous speaker. Second, several cases have arisen in the United States where plaintiffs have requested that the identity of an anonymous Internet speaker be revealed.  These cases are surveyed.  Third, the cases are analyzed in order to determine the factors that courts require to be present before the identity of an anonymous speaker will be revealed.  The release is typically accomplished by the enforcement of a discovery subpoena instigated by the party seeking the identity of the anonymous speaker. The factors courts have used are as follows: jurisdiction, good faith (both internal and external, necessity (basic and sometimes absolute, and at times proprietary interest. Finally, these factors are applied in three scenarios--e-commerce, education, and employment--to guide institutions when adopting policies that regulate when the identity of an anonymous speaker--a customer, a student or an employee--would be released as part of an internal initiative, but would nonetheless be consistent with developing legal standards.

  18. Verbal Venting in the Social Web: Effects of Anonymity and Group Norms on Aggressive Language Use in Online Comments

    Directory of Open Access Journals (Sweden)

    Leonie Rösner

    2016-08-01

    Full Text Available Scholars often blame the occurrence of aggressive behavior in online discussions on the anonymity of the Internet; however, even on today’s less anonymous platforms, such as social networking sites, users write plenty of aggressive comments, which can elicit a whole wave of negative remarks. Drawing on the social identity and deindividuation effects (SIDE model, this research conducts a laboratory experiment with a 2 (anonymity vs. no anonymity × 2 (aggressive norm vs. non-aggressive norm between-subjects design in order to disentangle the effects of anonymity, social group norms, and their interactions on aggressive language use in online comments. Results reveal that participants used more aggressive expressions in their comments when peer comments on a blog included aggressive wording (i.e., the social group norm was aggressive. Anonymity had no direct effect; however, we found a tendency that users’ conformity to an aggressive social norm of commenting is stronger in an anonymous environment.

  19. 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.

  20. 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...

  1. Research on presentation and query service of geo-spatial data based on ontology

    Science.gov (United States)

    Li, Hong-wei; Li, Qin-chao; Cai, Chang

    2008-10-01

    The paper analyzed the deficiency on presentation and query of geo-spatial data existed in current GIS, discussed the advantages that ontology possessed in formalization of geo-spatial data and the presentation of semantic granularity, taken land-use classification system as an example to construct domain ontology, and described it by OWL; realized the grade level and category presentation of land-use data benefited from the thoughts of vertical and horizontal navigation; and then discussed query mode of geo-spatial data based on ontology, including data query based on types and grade levels, instances and spatial relation, and synthetic query based on types and instances; these methods enriched query mode of current GIS, and is a useful attempt; point out that the key point of the presentation and query of spatial data based on ontology is to construct domain ontology that can correctly reflect geo-concept and its spatial relation and realize its fine formalization description.

  2. 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.

  3. How to Bootstrap Anonymous Communication

    DEFF Research Database (Denmark)

    Jakobsen, Sune K.; Orlandi, Claudio

    2015-01-01

    formal study in this direction. To solve this problem, we introduce the concept of anonymous steganography: think of a leaker Lea who wants to leak a large document to Joe the journalist. Using anonymous steganography Lea can embed this document in innocent looking communication on some popular website...... anonymous steganography, { A construction showing that anonymous steganography is possible (which uses recent results in circuits obfuscation), { A lower bound on the number of bits which are needed to bootstrap anonymous communication....

  4. How to Bootstrap Anonymous Communication

    DEFF Research Database (Denmark)

    Jakobsen, Sune K.; Orlandi, Claudio

    2015-01-01

    formal study in this direction. To solve this problem, we introduce the concept of anonymous steganography: think of a leaker Lea who wants to leak a large document to Joe the journalist. Using anonymous steganography Lea can embed this document in innocent looking communication on some popular website...... defining anonymous steganography, - A construction showing that anonymous steganography is possible (which uses recent results in circuits obfuscation), - A lower bound on the number of bits which are needed to bootstrap anonymous communication....

  5. Anonymous steps: gender and Gamblers Anonymous

    OpenAIRE

    Rogers, Jim

    2015-01-01

    The biggest source of help for problem gamblers remains gamblers anonymous (GA) in terms of accessibility and availability. GA has traditionally been very much a male preserve. This paper reports on a literature review of Gamblers Anonymous together with data from observations of a contemporary open GA meeting over a one year period. Whilst some studies from North America suggest a changing culture and gender balance within GA programmes observations from the North of England, supported b...

  6. An Anonymous Access Authentication Scheme Based on Proxy Ring Signature for CPS-WMNs

    Directory of Open Access Journals (Sweden)

    Tianhan Gao

    2017-01-01

    Full Text Available Access security and privacy have become a bottleneck for the popularization of future Cyber-Physical System (CPS networks. Furthermore, users’ need for privacy-preserved access during movement procedure is more urgent. To address the anonymous access authentication issue for CPS Wireless Mesh Network (CPS-WMN, a novel anonymous access authentication scheme based on proxy ring signature is proposed. A hierarchical authentication architecture is presented first. The scheme is then achieved from the aspect of intergroup and intragroup anonymous mutual authentication through proxy ring signature mechanism and certificateless signature mechanism, respectively. We present a formal security proof of the proposed protocol with SVO logic. The simulation and performance analysis demonstrate that the proposed scheme owns higher efficiency and adaptability than the typical one.

  7. Web-based topology queries on a BIM model

    DEFF Research Database (Denmark)

    Rasmussen, Mads Holten; Hviid, Christian Anker; Karlshøj, Jan

    Building Information Modeling (BIM) is in the industry often confused with 3D-modeling regardless that the potential of modeling information goes way beyond performing clash detections on geometrical objects occupying the same physical space. Lately, several research projects have tried to change...... that by extending BIM with information using linked data technologies. However, when showing information alone the strong communication benefits of 3D are neglected, and a practical way of connecting the two worlds is currently missing. In this paper, we present a prototype of a visual query interface running...... is to establish a baseline for discussion of the general design choices that have been considered, and the developed application further serves as a proof of concept for combining BIM model data with a knowledge graph and potentially other sources of Linked Open Data, in a simple web interface....

  8. 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...

  9. Interim policy on establishment and operation of internet open, anonymous information servers and services

    OpenAIRE

    Acting Dean of Computer and Information Services

    1995-01-01

    Purpose. To establish interim NPS general policy regarding establishment and operation of Open, Anonymous Information Servers and Services, such as World Wide Web (http), Gopher, Anonymous FTP, etc...

  10. Anonymous Authentication Systems Based on Private Information Retrieval

    OpenAIRE

    Nakamura, Toru; Inenaga, Shunsuke; Ikeda, Daisuke; Baba, Kensuke; Yasuura, Hiroto

    2009-01-01

    This paper focuses on authentication with three types of entities: a user who sends an authentication request, an authentication-server who receives and verifies the request, and a database who supplies the authentication-server with information for verifying the request. This paper presents novel authentication protocols that satisfy the following important properties: (1) secure against replay attacks, (2) the database(s) cannot identify which user is authenticating and (3) the authenticati...

  11. 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.

  12. 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).

  13. 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.

  14. Trust in Anonymity Networks

    Science.gov (United States)

    Sassone, Vladimiro; Hamadou, Sardaouna; Yang, Mu

    Anonymity is a security property of paramount importance, as we move steadily towards a wired, online community. Its import touches upon subjects as different as eGovernance, eBusiness and eLeisure, as well as personal freedom of speech in authoritarian societies. Trust metrics are used in anonymity networks to support and enhance reliability in the absence of verifiable identities, and a variety of security attacks currently focus on degrading a user's trustworthiness in the eyes of the other users. In this paper, we analyse the privacy guarantees of the Crowds anonymity protocol, with and without onion forwarding, for standard and adaptive attacks against the trust level of honest users.

  15. Most Recent Match Queries in On-Line Suffix Trees

    DEFF Research Database (Denmark)

    Larsson, N. Jesper

    2014-01-01

    A suffix tree is able to efficiently locate a pattern in an indexed string, but not in general the most recent copy of the pattern in an online stream, which is desirable in some applications. We study the most general version of the problem of locating a most recent match: supporting queries...

  16. NoDB: efficient query execution on raw data files

    NARCIS (Netherlands)

    I. Alagiannis; R Borovica; M. Branco; S. Idreos (Stratos); A. Ailamaki

    2012-01-01

    htmlabstractAs data collections become larger and larger, data loading evolves to a major bottleneck. Many applications already avoid using database systems, e.g., scientific data analysis and social networks, due to the complexity and the increased data-to-query time. For such applications data

  17. THE WIKILEAKS´S CASE AND ANONYMITY: EFFECTS ON THE INFORMATION FREEDOM

    Directory of Open Access Journals (Sweden)

    Marlus Heriberto Arns de Oliveira

    2015-10-01

    Full Text Available The Constitution of the Federative Republic of Brazil, enacted in 1988 during the democratization process of the country after the end of an authoritarian regime preceded by several others that show a non-democratic tradition in the Brazilian Republic, remained still remnants an authoritarian Patronizing and Paternalist state, the example of the final part of the Article 5, item IV, which claims to be the free expression of thought, but forbids anonymity, prohibition which deserves to be rethought, especially on the internet, where the navigation data of people deserve protection, as well as their rights to remain anonymous, a fact which entails the need for reflection on the scope and how best to interpret the constitutional provision cited, a debate that, in the proposed article will deal think the ideas of paternalism, authoritarianism and freedom, whose focus will be about within the Internet, social networks and the Knowledge Society.

  18. Robust Runtime Optimization and Skew-Resistant Execution of Analytical SPARQL Queries on Pig

    NARCIS (Netherlands)

    S Kotoulas; J. Urbani; P.A. Boncz (Peter); P. Mika

    2012-01-01

    textabstractWe describe a system that incrementally translates SPARQL queries to Pig Latin and executes them on a Hadoop cluster. This system is designed to work eciently on complex queries with many self-joins over huge datasets, avoiding job failures even in the case of joins with unexpected

  19. Moves on the Street: Classifying Crime Hotspots Using Aggregated Anonymized Data on People Dynamics.

    Science.gov (United States)

    Bogomolov, Andrey; Lepri, Bruno; Staiano, Jacopo; Letouzé, Emmanuel; Oliver, Nuria; Pianesi, Fabio; Pentland, Alex

    2015-09-01

    The wealth of information provided by real-time streams of data has paved the way for life-changing technological advancements, improving the quality of life of people in many ways, from facilitating knowledge exchange to self-understanding and self-monitoring. Moreover, the analysis of anonymized and aggregated large-scale human behavioral data offers new possibilities to understand global patterns of human behavior and helps decision makers tackle problems of societal importance. In this article, we highlight the potential societal benefits derived from big data applications with a focus on citizen safety and crime prevention. First, we introduce the emergent new research area of big data for social good. Next, we detail a case study tackling the problem of crime hotspot classification, that is, the classification of which areas in a city are more likely to witness crimes based on past data. In the proposed approach we use demographic information along with human mobility characteristics as derived from anonymized and aggregated mobile network data. The hypothesis that aggregated human behavioral data captured from the mobile network infrastructure, in combination with basic demographic information, can be used to predict crime is supported by our findings. Our models, built on and evaluated against real crime data from London, obtain accuracy of almost 70% when classifying whether a specific area in the city will be a crime hotspot or not in the following month.

  20. An Efficient Big Data Anonymization Algorithm Based on Chaos and Perturbation Techniques

    Directory of Open Access Journals (Sweden)

    Can Eyupoglu

    2018-05-01

    Full Text Available The topic of big data has attracted increasing interest in recent years. The emergence of big data leads to new difficulties in terms of protection models used for data privacy, which is of necessity for sharing and processing data. Protecting individuals’ sensitive information while maintaining the usability of the data set published is the most important challenge in privacy preserving. In this regard, data anonymization methods are utilized in order to protect data against identity disclosure and linking attacks. In this study, a novel data anonymization algorithm based on chaos and perturbation has been proposed for privacy and utility preserving in big data. The performance of the proposed algorithm is evaluated in terms of Kullback–Leibler divergence, probabilistic anonymity, classification accuracy, F-measure and execution time. The experimental results have shown that the proposed algorithm is efficient and performs better in terms of Kullback–Leibler divergence, classification accuracy and F-measure compared to most of the existing algorithms using the same data set. Resulting from applying chaos to perturb data, such successful algorithm is promising to be used in privacy preserving data mining and data publishing.

  1. Private and Efficient Query Processing on Outsourced Genomic Databases.

    Science.gov (United States)

    Ghasemi, Reza; Al Aziz, Md Momin; Mohammed, Noman; Dehkordi, Massoud Hadian; Jiang, Xiaoqian

    2017-09-01

    Applications of genomic studies are spreading rapidly in many domains of science and technology such as healthcare, biomedical research, direct-to-consumer services, and legal and forensic. However, there are a number of obstacles that make it hard to access and process a big genomic database for these applications. First, sequencing genomic sequence is a time consuming and expensive process. Second, it requires large-scale computation and storage systems to process genomic sequences. Third, genomic databases are often owned by different organizations, and thus, not available for public usage. Cloud computing paradigm can be leveraged to facilitate the creation and sharing of big genomic databases for these applications. Genomic data owners can outsource their databases in a centralized cloud server to ease the access of their databases. However, data owners are reluctant to adopt this model, as it requires outsourcing the data to an untrusted cloud service provider that may cause data breaches. In this paper, we propose a privacy-preserving model for outsourcing genomic data to a cloud. The proposed model enables query processing while providing privacy protection of genomic databases. Privacy of the individuals is guaranteed by permuting and adding fake genomic records in the database. These techniques allow cloud to evaluate count and top-k queries securely and efficiently. Experimental results demonstrate that a count and a top-k query over 40 Single Nucleotide Polymorphisms (SNPs) in a database of 20 000 records takes around 100 and 150 s, respectively.

  2. 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.

  3. A study on PubMed search tag usage pattern: association rule mining of a full-day PubMed query log.

    Science.gov (United States)

    Mosa, Abu Saleh Mohammad; Yoo, Illhoi

    2013-01-09

    The practice of evidence-based medicine requires efficient biomedical literature search such as PubMed/MEDLINE. Retrieval performance relies highly on the efficient use of search field tags. The purpose of this study was to analyze PubMed log data in order to understand the usage pattern of search tags by the end user in PubMed/MEDLINE search. A PubMed query log file was obtained from the National Library of Medicine containing anonymous user identification, timestamp, and query text. Inconsistent records were removed from the dataset and the search tags were extracted from the query texts. A total of 2,917,159 queries were selected for this study issued by a total of 613,061 users. The analysis of frequent co-occurrences and usage patterns of the search tags was conducted using an association mining algorithm. The percentage of search tag usage was low (11.38% of the total queries) and only 2.95% of queries contained two or more tags. Three out of four users used no search tag and about two-third of them issued less than four queries. Among the queries containing at least one tagged search term, the average number of search tags was almost half of the number of total search terms. Navigational search tags are more frequently used than informational search tags. While no strong association was observed between informational and navigational tags, six (out of 19) informational tags and six (out of 29) navigational tags showed strong associations in PubMed searches. The low percentage of search tag usage implies that PubMed/MEDLINE users do not utilize the features of PubMed/MEDLINE widely or they are not aware of such features or solely depend on the high recall focused query translation by the PubMed's Automatic Term Mapping. The users need further education and interactive search application for effective use of the search tags in order to fulfill their biomedical information needs from PubMed/MEDLINE.

  4. Big Data Analytics with Datalog Queries on Spark.

    Science.gov (United States)

    Shkapsky, Alexander; Yang, Mohan; Interlandi, Matteo; Chiu, Hsuan; Condie, Tyson; Zaniolo, Carlo

    2016-01-01

    There is great interest in exploiting the opportunity provided by cloud computing platforms for large-scale analytics. Among these platforms, Apache Spark is growing in popularity for machine learning and graph analytics. Developing efficient complex analytics in Spark requires deep understanding of both the algorithm at hand and the Spark API or subsystem APIs (e.g., Spark SQL, GraphX). Our BigDatalog system addresses the problem by providing concise declarative specification of complex queries amenable to efficient evaluation. Towards this goal, we propose compilation and optimization techniques that tackle the important problem of efficiently supporting recursion in Spark. We perform an experimental comparison with other state-of-the-art large-scale Datalog systems and verify the efficacy of our techniques and effectiveness of Spark in supporting Datalog-based analytics.

  5. A reciprocal framework for spatial K-anonymity

    KAUST Repository

    Ghinita, Gabriel; Zhao, Keliang; Papadias, Dimitris; Kalnis, Panos

    2010-01-01

    Spatial K-anonymity (SKA) exploits the concept of K-anonymity in order to protect the identity of users from location-based attacks. The main idea of SKA is to replace the exact location of a user U with an anonymizing spatial region (ASR) that contains at least K-1 other users, so that an attacker can pinpoint U with probability at most 1/K. Simply generating an ASR that includes K users does not guarantee SKA. Previous work defined the reciprocity property as a sufficient condition for SKA. However, the only existing reciprocal method, Hilbert Cloak, relies on a specialized data structure. In contrast, we propose a general framework for implementing reciprocal algorithms using any existing spatial index on the user locations. We discuss ASR construction methods with different tradeoffs on effectiveness (i.e., ASR size) and efficiency (i.e., construction cost). Then, we present case studies of applying our framework on top of two popular spatial indices (namely, R*-trees and Quad-trees). Finally, we consider the case where the attacker knows the query patterns of each user. The experimental results verify that our methods outperform Hilbert Cloak. Moreover, since we employ general-purpose spatial indices, the proposed system is not limited to anonymization, but supports conventional spatial queries as well. © 2009 Elsevier B.V. All rights reserved.

  6. A reciprocal framework for spatial K-anonymity

    KAUST Repository

    Ghinita, Gabriel

    2010-05-01

    Spatial K-anonymity (SKA) exploits the concept of K-anonymity in order to protect the identity of users from location-based attacks. The main idea of SKA is to replace the exact location of a user U with an anonymizing spatial region (ASR) that contains at least K-1 other users, so that an attacker can pinpoint U with probability at most 1/K. Simply generating an ASR that includes K users does not guarantee SKA. Previous work defined the reciprocity property as a sufficient condition for SKA. However, the only existing reciprocal method, Hilbert Cloak, relies on a specialized data structure. In contrast, we propose a general framework for implementing reciprocal algorithms using any existing spatial index on the user locations. We discuss ASR construction methods with different tradeoffs on effectiveness (i.e., ASR size) and efficiency (i.e., construction cost). Then, we present case studies of applying our framework on top of two popular spatial indices (namely, R*-trees and Quad-trees). Finally, we consider the case where the attacker knows the query patterns of each user. The experimental results verify that our methods outperform Hilbert Cloak. Moreover, since we employ general-purpose spatial indices, the proposed system is not limited to anonymization, but supports conventional spatial queries as well. © 2009 Elsevier B.V. All rights reserved.

  7. On Describing Human White Matter Anatomy: The White Matter Query Language

    OpenAIRE

    Wassermann, Demian; Makris, Nikos; Rathi, Yogesh; Shenton, Martha; Kikinis, Ron; Kubicki, Marek; Westin, Carl-Fredrik

    2013-01-01

    The main contribution of this work is the careful syntactical definition of major white matter tracts in the human brain based on a neuroanatomist’s expert knowledge. We present a technique to formally describe white matter tracts and to automatically extract them from diffusion MRI data. The framework is based on a novel query language with a near-to-English textual syntax. This query language allows us to construct a dictionary of anatomical definitions describing white matter tracts. The d...

  8. Practical private database queries based on a quantum-key-distribution protocol

    International Nuclear Information System (INIS)

    Jakobi, Markus; Simon, Christoph; Gisin, Nicolas; Bancal, Jean-Daniel; Branciard, Cyril; Walenta, Nino; Zbinden, Hugo

    2011-01-01

    Private queries allow a user, Alice, to learn an element of a database held by a provider, Bob, without revealing which element she is interested in, while limiting her information about the other elements. We propose to implement private queries based on a quantum-key-distribution protocol, with changes only in the classical postprocessing of the key. This approach makes our scheme both easy to implement and loss tolerant. While unconditionally secure private queries are known to be impossible, we argue that an interesting degree of security can be achieved by relying on fundamental physical principles instead of unverifiable security assumptions in order to protect both the user and the database. We think that the scope exists for such practical private queries to become another remarkable application of quantum information in the footsteps of quantum key distribution.

  9. 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.

  10. 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.

  11. A hidden service model based on HS-HS anonymous network

    Science.gov (United States)

    Meng, Yitong; Zhao, Xing; Fei, Jinlong; Zhu, Yuefei

    2017-10-01

    The Hidden Service provided by Tor anonymous network can effectively protect the anonymity and security of the Hidden server, this article through the analysis of the data packet structure of Tor, three jump transmission mechanism and link establishment protocol and Hidden Service communication process, in view of the Hidden node number too much, link building Service for too long and too redundant link problem. An improved hidden service model HS-HS is proposed that incorporating multiple transmission link and reuse, and at the same time will be important transit point for reuse protection link anonymity, through the ExperimenTor simulation environment test, verify the improved model of HS-HS can be more effective in guarantee anonymity and security, improve the overall efficiency of data transmission, to meet the needs of today's anonymous service.

  12. 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...

  13. Effects of Cultural Orientation on Attitude Toward Anonymity in E-Collaboration

    Science.gov (United States)

    Zhong, Yingqin; Liu, Na; Lim, John

    The important role of attitude in the acceptance and diffusion of technology has been widely acknowledged. Greater research efforts have been called for examining the relationships between cultural variables and attitude toward technology. In this regard, this study investigates the impact of cultural orientation (focusing on an individual's degree of collectivism) on attitude toward e-collaboration technology. A theoretical model is proposed and subsequently tested using a questionnaire survey involving 236 data points. Self-reliance, competitive success, and group work orientation are found as significant indicators reflecting an individual's degree of collectivism, which in turn influences willingness to participate, evaluation of collaborative effort, and preference for anonymity feature. Subsequently, the three variables are found to affect perceptions about decision quality, enjoyment, uncertainty, and pressure in e-collaboration.

  14. Complex analyses on clinical information systems using restricted natural language querying to resolve time-event dependencies.

    Science.gov (United States)

    Safari, Leila; Patrick, Jon D

    2018-06-01

    This paper reports on a generic framework to provide clinicians with the ability to conduct complex analyses on elaborate research topics using cascaded queries to resolve internal time-event dependencies in the research questions, as an extension to the proposed Clinical Data Analytics Language (CliniDAL). A cascaded query model is proposed to resolve internal time-event dependencies in the queries which can have up to five levels of criteria starting with a query to define subjects to be admitted into a study, followed by a query to define the time span of the experiment. Three more cascaded queries can be required to define control groups, control variables and output variables which all together simulate a real scientific experiment. According to the complexity of the research questions, the cascaded query model has the flexibility of merging some lower level queries for simple research questions or adding a nested query to each level to compose more complex queries. Three different scenarios (one of them contains two studies) are described and used for evaluation of the proposed solution. CliniDAL's complex analyses solution enables answering complex queries with time-event dependencies at most in a few hours which manually would take many days. An evaluation of results of the research studies based on the comparison between CliniDAL and SQL solutions reveals high usability and efficiency of CliniDAL's solution. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. 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.

  16. 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

  17. Alcoholics Anonymous

    Science.gov (United States)

    ... Arab Emirates United Kingdom United States Uruguay Venezuela Virgin Islands Zimbabwe INFORMATION ABOUT A.A. What Is ... Young People's Animation Video On the Beach A Group of People Just Like Me Full-Length Videos ...

  18. PiCO QL: A software library for runtime interactive queries on program data

    Science.gov (United States)

    Fragkoulis, Marios; Spinellis, Diomidis; Louridas, Panos

    PiCO QL is an open source C/C++ software whose scientific scope is real-time interactive analysis of in-memory data through SQL queries. It exposes a relational view of a system's or application's data structures, which is queryable through SQL. While the application or system is executing, users can input queries through a web-based interface or issue web service requests. Queries execute on the live data structures through the respective relational views. PiCO QL makes a good candidate for ad-hoc data analysis in applications and for diagnostics in systems settings. Applications of PiCO QL include the Linux kernel, the Valgrind instrumentation framework, a GIS application, a virtual real-time observatory of stellar objects, and a source code analyser.

  19. PiCO QL: A software library for runtime interactive queries on program data

    Directory of Open Access Journals (Sweden)

    Marios Fragkoulis

    2016-01-01

    Full Text Available Pico ql is an open source c/c++ software whose scientific scope is real-time interactive analysis of in-memory data through sql queries. It exposes a relational view of a system’s or application’s data structures, which is queryable through sql. While the application or system is executing, users can input queries through a web-based interface or issue web service requests. Queries execute on the live data structures through the respective relational views. pico ql makes a good candidate for ad-hoc data analysis in applications and for diagnostics in systems settings. Applications of pico ql include the Linux kernel, the Valgrind instrumentation framework, a gis application, a virtual real-time observatory of stellar objects, and a source code analyser.

  20. An overview of anonymity and anonymous communication

    NARCIS (Netherlands)

    Koot, M.

    2008-01-01

    Privacy is becoming an increasingly important aspect in distributed systems. In anonymous communication, privacy is provided to communicating parties by hiding their identities from each other and/or from others. This paper discusses the problem of anonymous communication and clarifies the notion of

  1. BIX Certificates: Cryptographic Tokens for Anonymous Transactions Based on Certificates Public Ledger

    Directory of Open Access Journals (Sweden)

    Sead Muftic

    2016-12-01

    Full Text Available With the widespread use of Internet, Web, and mobile technologies, a new category of applications and transactions that requires anonymity is gaining increased interest and importance. Examples of such new applications are innovative payment systems, digital notaries, electronic voting, documents sharing, electronic auctions, medical applications, and many others. In addition to anonymity, these applications and transactions also require standard security services: identification, authentication, and authorization of users and protection of their transactions. Providing those services in combination with anonymity is an especially challenging issue, because all security services require explicit user identification and authentication. To solve this issue and enable applications with security and also anonymity we introduce a new type of cryptographically encapsulated objects called BIX certificates. “BIX” is an abbreviation for “Blockchain Information Exchange.” Their purpose is equivalent to X.509 certificates: to support security services for users and transactions, but also enhanced with anonymity. This paper describes the structure and attributes of BIX certificate objects and all related protocols for their creation, distribution, and use. The BIX Certification Infrastructure (BCI as a distributed public ledger is also briefly described.

  2. Alcoholics Anonymous and twelve-step recovery: a model based on social and cognitive neuroscience.

    Science.gov (United States)

    Galanter, Marc

    2014-01-01

    In the course of achieving abstinence from alcohol, longstanding members of Alcoholics Anonymous (AA) typically experience a change in their addiction-related attitudes and behaviors. These changes are reflective of physiologically grounded mechanisms which can be investigated within the disciplines of social and cognitive neuroscience. This article is designed to examine recent findings associated with these disciplines that may shed light on the mechanisms underlying this change. Literature review and hypothesis development. Pertinent aspects of the neural impact of drugs of abuse are summarized. After this, research regarding specific brain sites, elucidated primarily by imaging techniques, is reviewed relative to the following: Mirroring and mentalizing are described in relation to experimentally modeled studies on empathy and mutuality, which may parallel the experiences of social interaction and influence on AA members. Integration and retrieval of memories acquired in a setting like AA are described, and are related to studies on storytelling, models of self-schema development, and value formation. A model for ascription to a Higher Power is presented. The phenomena associated with AA reflect greater complexity than the empirical studies on which this article is based, and certainly require further elucidation. Despite this substantial limitation in currently available findings, there is heuristic value in considering the relationship between the brain-based and clinical phenomena described here. There are opportunities for the study of neuroscientific correlates of Twelve-Step-based recovery, and these can potentially enhance our understanding of related clinical phenomena. © American Academy of Addiction Psychiatry.

  3. Long-Term Influence of Duration and Frequency of Participation in Alcoholics Anonymous on Individuals With Alcohol Use Disorders.

    Science.gov (United States)

    Moos, Rudolf H.; Moos, Bernice S.

    2004-01-01

    This study examined the influence of the duration and frequency of a baseline episode of participation in Alcoholics Anonymous (AA) among 473 individuals with alcohol use disorders on 1-year and 8-year outcomes and the effect of additional participation and delayed participation on outcomes. Compared with individuals who did not participate,…

  4. Anonymous Authentication for Smartcards

    Directory of Open Access Journals (Sweden)

    J. Hajny

    2010-06-01

    Full Text Available The paper presents an innovative solution in the field of RFID (Radio-Frequency IDentification smartcard authentication. Currently the smartcards are used for many purposes - e.g. employee identification, library cards, student cards or even identity credentials. Personal identity is revealed to untrustworthy entities every time we use these cards. Such information could later be used without our knowledge and for harmful reasons like shopping pattern scanning or even movement tracking. We present a communication scheme for keeping one’s identity private in this paper. Although our system provides anonymity, it does not allow users to abuse this feature. The system is based on strong cryptographic primitives that provide features never available before. Besides theoretical design of the anonymous authentication scheme and its analysis we also provide implementation results.

  5. 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

  6. 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

  7. Error Analysis of Ia Supernova and Query on Cosmic Dark Energy

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... Error Analysis of Ia Supernova and Query on Cosmic Dark Energy. Qiuhe Peng Yiming Hu Kun ... https://www.ias.ac.in/article/fulltext/joaa/035/03/0253-0256 ... Articles are also visible in Web of Science immediately. All these ...

  8. Manually Classifying User Search Queries on an Academic Library Web Site

    Science.gov (United States)

    Chapman, Suzanne; Desai, Shevon; Hagedorn, Kat; Varnum, Ken; Mishra, Sonali; Piacentine, Julie

    2013-01-01

    The University of Michigan Library wanted to learn more about the kinds of searches its users were conducting through the "one search" search box on the Library Web site. Library staff conducted two investigations. A preliminary investigation in 2011 involved the manual review of the 100 most frequently occurring queries conducted…

  9. Modeling and query the uncertainty of network constrained moving objects based on RFID data

    Science.gov (United States)

    Han, Liang; Xie, Kunqing; Ma, Xiujun; Song, Guojie

    2007-06-01

    The management of network constrained moving objects is more and more practical, especially in intelligent transportation system. In the past, the location information of moving objects on network is collected by GPS, which cost high and has the problem of frequent update and privacy. The RFID (Radio Frequency IDentification) devices are used more and more widely to collect the location information. They are cheaper and have less update. And they interfere in the privacy less. They detect the id of the object and the time when moving object passed by the node of the network. They don't detect the objects' exact movement in side the edge, which lead to a problem of uncertainty. How to modeling and query the uncertainty of the network constrained moving objects based on RFID data becomes a research issue. In this paper, a model is proposed to describe the uncertainty of network constrained moving objects. A two level index is presented to provide efficient access to the network and the data of movement. The processing of imprecise time-slice query and spatio-temporal range query are studied in this paper. The processing includes four steps: spatial filter, spatial refinement, temporal filter and probability calculation. Finally, some experiments are done based on the simulated data. In the experiments the performance of the index is studied. The precision and recall of the result set are defined. And how the query arguments affect the precision and recall of the result set is also discussed.

  10. 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.

  11. 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.

  12. Fast, Just-in-Time Queries on Heterogeneous Raw Data

    CERN Multimedia

    CERN. Geneva

    2017-01-01

    Today’s scientific and business processes heavily depend on fast and accurate data analysis. Data scientists are routinely overwhelmed by the effort needed to manage the volumes of data produced. As general-purpose data management software is often inefficient, hard to manage, or too generic to serve today's applications, businesses increasingly turn to specialised data management software, which can only handle one data format, and then resort to data integration solutions. With the exponential growth of dataset size and complexity, however, data format-specific solutions no longer scale for efficient analysis, thereby slowing down the cycle of analysing and understanding the data, and making decisions. I will illustrate the different nature of problems we face when managing heterogeneous datasets, and how these translate to fundamental challenges for the data management community. Then I will introduce new technologies inspired by these challenges, which overturn long-stangding assumptions, enable meaning...

  13. Improving Estimation Accuracy of Aggregate Queries on Data Cubes

    Energy Technology Data Exchange (ETDEWEB)

    Pourabbas, Elaheh; Shoshani, Arie

    2008-08-15

    In this paper, we investigate the problem of estimation of a target database from summary databases derived from a base data cube. We show that such estimates can be derived by choosing a primary database which uses a proxy database to estimate the results. This technique is common in statistics, but an important issue we are addressing is the accuracy of these estimates. Specifically, given multiple primary and multiple proxy databases, that share the same summary measure, the problem is how to select the primary and proxy databases that will generate the most accurate target database estimation possible. We propose an algorithmic approach for determining the steps to select or compute the source databases from multiple summary databases, which makes use of the principles of information entropy. We show that the source databases with the largest number of cells in common provide the more accurate estimates. We prove that this is consistent with maximizing the entropy. We provide some experimental results on the accuracy of the target database estimation in order to verify our results.

  14. 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...

  15. Social influence in computer-mediated communication : The effects of anonymity on group behavior

    NARCIS (Netherlands)

    Postmes, T; Spears, R; Sakhel, K; de Groot, D

    2001-01-01

    Two studies examined hypotheses derived from a Social Identity model of Deindividuation Effects (SIDE) as applied to social influence in computer-mediated communication (CMC) in groups. This model predicts that anonymity can increase social influence if a common group identity is salient. In a first

  16. 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

  17. 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

  18. Anonymous Credential Schemes with Encrypted Attributes

    NARCIS (Netherlands)

    Guajardo Merchan, J.; Mennink, B.; Schoenmakers, B.

    2011-01-01

    In anonymous credential schemes, users obtain credentials on certain attributes from an issuer, and later show these credentials to a relying party anonymously and without fully disclosing the attributes. In this paper, we introduce the notion of (anonymous) credential schemes with encrypted

  19. Anonymous Boh avatud kunsti maastikul / Raivo Kelomees

    Index Scriptorium Estoniae

    Kelomees, Raivo, 1960-

    2010-01-01

    Anonymous Bohi näitus Tartu Kunstimajas, avatud 30. juulini 2010. Anonymous Boh on koos Non Grataga läbi viinud performance´id Euroopas, Ameerikas ja Aasias. Anonymous Bohi vastused oma näituse ja loominguga seotud küsimustele

  20. 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.

  1. Facebook’s Ugly Sisters: Anonymity and Abuse on Formspring and Ask.fm

    OpenAIRE

    Binns, Amy

    2013-01-01

    New question and answer websites Ask.fm and Formspring have brought highly specific and personal abuse to a new level amongst young people by providing easy anonymity to users within a circle of offline friendship groups culled from Facebook. Relatively unknown due to their unattractiveness to adults, these sites are growing rapidly and have already been associated with at least eight suicides amongst teenagers. \\ud \\ud Media educators at school level encouraging self-awareness of social medi...

  2. A Comparison of the Effects of K-Anonymity on Machine Learning Algorithms

    OpenAIRE

    Hayden Wimmer; Loreen Powell

    2014-01-01

    While research has been conducted in machine learning algorithms and in privacy preserving in data mining (PPDM), a gap in the literature exists which combines the aforementioned areas to determine how PPDM affects common machine learning algorithms. The aim of this research is to narrow this literature gap by investigating how a common PPDM algorithm, K-Anonymity, affects common machine learning and data mining algorithms, namely neural networks, logistic regression, decision trees, and Baye...

  3. 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.

  4. 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.

  5. Quantum anonymous voting with anonymity check

    International Nuclear Information System (INIS)

    Horoshko, Dmitri; Kilin, Sergei

    2011-01-01

    We propose a new protocol for quantum anonymous voting having serious advantages over the existing protocols: it protects both the voters from a curious tallyman and all the participants from a dishonest voter in unconditional way. The central idea of the protocol is that the ballots are given back to the voters after the voting process, which gives a possibility for two voters to check the anonymity of the vote counting process by preparing a special entangled state of two ballots. Any attempt of cheating from the side of the tallyman results in destroying the entanglement, which can be detected by the voters.

  6. INTEGRATIVE METHOD OF TEACHING INFORMATION MODELING IN PRACTICAL HEALTH SERVICE BASED ON MICROSOFT ACCESS QUERIES

    Directory of Open Access Journals (Sweden)

    Svetlana A. Firsova

    2016-06-01

    Full Text Available Introduction: this article explores the pedagogical technology employed to teach medical students foundations of work with MICROSOFT ACCESS databases. The above technology is based on integrative approach to the information modeling in public health practice, drawing upon basic didactic concepts that pertain to objects and tools databases created in MICROSOFT ACCESS. The article examines successive steps in teaching the topic “Queries in MICROSOFT ACCESS” – from simple queries to complex ones. The main attention is paid to such components of methodological system, as the principles and teaching methods classified according to the degree of learners’ active cognitive activity. The most interesting is the diagram of the relationship of learning principles, teaching methods and specific types of requests. Materials and Methods: the authors used comparative analysis of literature, syllabi, curricula in medical informatics taught at leading medical universities in Russia. Results: the original technique of training in putting queries with databases of MICROSOFT ACCESS is presented for analysis of information models in practical health care. Discussion and Conclusions: it is argued that the proposed pedagogical technology will significantly improve the effectiveness of teaching the course “Medical Informatics”, that includes development and application of models to simulate the operation of certain facilities and services of the health system which, in turn, increases the level of information culture of practitioners.

  7. Data anonymization patent landscape

    Directory of Open Access Journals (Sweden)

    Mirjana Pejić Bach

    2017-01-01

    Full Text Available The omnipresent, unstoppable increase in digital data has led to a greater understanding of the importance of data privacy. Different approaches are used to implement data privacy. The goal of this paper is to develop a data anonymization patent landscape, by determining the following: (i the trend in data anonymization patenting, (ii the type of technical content protected in data anonymization, (iii the organizations and countries most active in patenting data anonymization know-how; and (iv the topics emerging most often in patent titles. Patents from the PatSeer database relating to data anonymization from 2001 to 2015 were analyzed. We used the longitudinal approach in combination with text mining techniques to develop a data anonymization patent landscape. The results indicated the following. The number of single patent families is growing with a high increase after 2010, thus indicating a positive trend in the area of patenting data anonymization solutions. The majority of patenting activities relate to the G Physics section. Organizations from the USA and Japan assigned the majority of patents related to data anonymization. The results of text mining indicate that the most often used word in titles of data anonymization patents are “anonym*, “method”, “data” and “system”. Several additional words that indicated the most frequent topics related to data anonymization were: “equipment”, “software”, “protection”, “identification”, or “encryption”, and specific topics such as “community”, “medical”, or “service”.

  8. Pattern-Guided k-Anonymity

    Directory of Open Access Journals (Sweden)

    Rolf Niedermeier

    2013-10-01

    Full Text Available We suggest a user-oriented approach to combinatorial data anonymization. A data matrix is called k-anonymous if every row appears at least k times—the goal of the NP-hard k-ANONYMITY problem then is to make a given matrix k-anonymous by suppressing (blanking out as few entries as possible. Building on previous work and coping with corresponding deficiencies, we describe an enhanced k-anonymization problem called PATTERN-GUIDED k-ANONYMITY, where the users specify in which combinations suppressions may occur. In this way, the user of the anonymized data can express the differing importance of various data features. We show that PATTERN-GUIDED k-ANONYMITY is NP-hard. We complement this by a fixed-parameter tractability result based on a “data-driven parameterization” and, based on this, develop an exact integer linear program (ILP-based solution method, as well as a simple, but very effective, greedy heuristic. Experiments on several real-world datasets show that our heuristic easily matches up to the established “Mondrian” algorithm for k-ANONYMITY in terms of the quality of the anonymization and outperforms it in terms of running time.

  9. Implementation of the common phrase index method on the phrase query for information retrieval

    Science.gov (United States)

    Fatmawati, Triyah; Zaman, Badrus; Werdiningsih, Indah

    2017-08-01

    As the development of technology, the process of finding information on the news text is easy, because the text of the news is not only distributed in print media, such as newspapers, but also in electronic media that can be accessed using the search engine. In the process of finding relevant documents on the search engine, a phrase often used as a query. The number of words that make up the phrase query and their position obviously affect the relevance of the document produced. As a result, the accuracy of the information obtained will be affected. Based on the outlined problem, the purpose of this research was to analyze the implementation of the common phrase index method on information retrieval. This research will be conducted in English news text and implemented on a prototype to determine the relevance level of the documents produced. The system is built with the stages of pre-processing, indexing, term weighting calculation, and cosine similarity calculation. Then the system will display the document search results in a sequence, based on the cosine similarity. Furthermore, system testing will be conducted using 100 documents and 20 queries. That result is then used for the evaluation stage. First, determine the relevant documents using kappa statistic calculation. Second, determine the system success rate using precision, recall, and F-measure calculation. In this research, the result of kappa statistic calculation was 0.71, so that the relevant documents are eligible for the system evaluation. Then the calculation of precision, recall, and F-measure produces precision of 0.37, recall of 0.50, and F-measure of 0.43. From this result can be said that the success rate of the system to produce relevant documents is low.

  10. PRIVACYGRID: Supporting Anonymous Location Queries in Mobile Environments

    Science.gov (United States)

    2007-01-01

    cid. 10: cidh ←− Horizontal neighbor cell of cid. 11: MNv = cid.MN + cidv.MN ; MNh = cid.MN + cidh.MN ; 12: SNv = cid.SN +cidv.SN ;SNh = cid.SN +cidh.SN...13: if (((MNv ≥ k) && (SNv ≥ l)) ‖ (( MNh ≥ k) && (SNh ≥ l))) then 14: if ((MNv ≥ k && MNh ≥ k && MNh > MNv) ‖ MNv < k) then 15: CheckCloakingBoxV...alidity(x, y, dx, dy) 16: return cid, cidh; 17: else 18: if ( MNh == MNv) then 19: if (SNh ≥ SNv) then 20: CheckCloakingBoxV alidity(x, y, dx, dy) 21

  11. Hardware Acceleration of SQL-Queries Processing in MDM-Systems Based on MISDSolution

    Directory of Open Access Journals (Sweden)

    V. E. Podol'skii

    2015-01-01

    Full Text Available In this article we examine the possibility of hardware support for functions of mobile device management platform (MDM-platform using a Multiple Instructions and Single Data stream computer system, developed within the framework of the project in Bauman Moscow State Technical University. At the universities the MDM-platform is used to provide various mobile services for the faculty, students and administration to facilitate the learning process: a mobile schedule, document sharing, text messages, and other interactive activities. Most of these services are provided by the extensive use of data stored in MDM-platform databases. When accessing the databases SQL- queries are commonly used. These queries comprise operators of SQL-language that are based on mathematical sets theory. Hardware support for operations on sets is implemented in Multiple Instructions and Single Data stream computer system (MISD System. This allows performance improvement of algorithms and operations on sets. Thus, the hardware support for the processing of SQL-queries in MISD system allows us to benefit from the implementation of SQL-queries in the MISD paradigm.The scientific novelty of the work lies in the fact that it is the first time a set of algorithms for basic SQL statements has been presented in a format supported by MISD system. In addition, for the first time operators INNER JOIN, LEFT JOIN and LEFT OUTER JOIN have been implemented for MISD system and tested for it (testing was done for FPGA Xilinx Virtex-II Pro XC2VP30 implementation of MISD system. The practical significance of the work lies in the fact that the results of the study will be used in the project "Development of the Russian analogue of the system software for centralized management of personal devices and platforms in enterprise networks" of the St. Petersburg Polytechnic University (with the financial support of the state represented by the Ministry of Education and Science of the Russian

  12. Data Retention and Anonymity Services

    Science.gov (United States)

    Berthold, Stefan; Böhme, Rainer; Köpsell, Stefan

    The recently introduced legislation on data retention to aid prosecuting cyber-related crime in Europe also affects the achievable security of systems for anonymous communication on the Internet. We argue that data retention requires a review of existing security evaluations against a new class of realistic adversary models. In particular, we present theoretical results and first empirical evidence for intersection attacks by law enforcement authorities. The reference architecture for our study is the anonymity service AN.ON, from which we also collect empirical data. Our adversary model reflects an interpretation of the current implementation of the EC Directive on Data Retention in Germany.

  13. Proxies for Anonymous Routing

    National Research Council Canada - National Science Library

    Reed, Michael G; Syverson, Paul F; Goldschlag, David M

    1996-01-01

    ...), and file transfers (FTP) have been implemented. Onion routing provides application independent, real-time, and bi-directional anonymous connections that are resistant to both eavesdropping and traffic analysis...

  14. An initial fMRI study on neural correlates of prayer in members of Alcoholics Anonymous.

    Science.gov (United States)

    Galanter, Marc; Josipovic, Zoran; Dermatis, Helen; Weber, Jochen; Millard, Mary Alice

    2017-01-01

    Many individuals with alcohol-use disorders who had experienced alcohol craving before joining Alcoholics Anonymous (AA) report little or no craving after becoming long-term members. Their use of AA prayers may contribute to this. Neural mechanisms underlying this process have not been delineated. To define experiential and neural correlates of diminished alcohol craving following AA prayers among members with long-term abstinence. Twenty AA members with long-term abstinence participated. Self-report measures and functional magnetic resonance imaging of differential neural response to alcohol-craving-inducing images were obtained in three conditions: after reading of AA prayers, after reading irrelevant news, and with passive viewing. Random-effects robust regressions were computed for the main effect (prayer > passive + news) and for estimating the correlations between the main effect and the self-report measures. Compared to the other two conditions, the prayer condition was characterized by: less self-reported craving; increased activation in left-anterior middle frontal gyrus, left superior parietal lobule, bilateral precuneus, and bilateral posterior middle temporal gyrus. Craving following prayer was inversely correlated with activation in brain areas associated with self-referential processing and the default mode network, and with characteristics reflecting AA program involvement. AA members' prayer was associated with a relative reduction in self-reported craving and with concomitant engagement of neural mechanisms that reflect control of attention and emotion. These findings suggest neural processes underlying the apparent effectiveness of AA prayer.

  15. [Comment onAnonymous reviews: Self-serving, counterproductive, and unacceptable”] from R.E. Criss and A.M. Hofmeister

    Science.gov (United States)

    Criss, Robert E.; Hofmeister, Anne M.

    We share many of the experiences and most of the sentiments relayed by Myrl Beck in his 1 July contribution to the Eos Forum, as well as those of a similar nature expressed by Alexander McBirney in his March 2003 commentary in GSA Today. We are in fact delighted that senior scientists are speaking up about the unsatisfactory nature of anonymous reviews. However, we believe they understate the problems, partly because the situation is worsening with time. Moreover, the brunt of such problems is disproportionately felt not by emeritus professors but by young scientists, women, and minorities, and this is the crux of the issue.This year, we have, like Beck, received rejections based on comments by two anonymous reviewers and an anonymous associate editor. We have also received rejections from anonymous associate editors based on a single constructive review requesting minor revision, along with an anonymous hostile “review” that could have been written about any manuscript on any topic by any author. More common than these are rejections from identified associate editors based on one or two anonymous reviews, which more often than not err on most of the points made, and in two cases dispute work that resulted in Nobel Prizes. We have examples this year of each type where the senior authors are recent Ph.D.s, whose vulnerabilities underscore the reprehensible nature of this “process.”

  16. Complex dynamics of our economic life on different scales: insights from search engine query data.

    Science.gov (United States)

    Preis, Tobias; Reith, Daniel; Stanley, H Eugene

    2010-12-28

    Search engine query data deliver insight into the behaviour of individuals who are the smallest possible scale of our economic life. Individuals are submitting several hundred million search engine queries around the world each day. We study weekly search volume data for various search terms from 2004 to 2010 that are offered by the search engine Google for scientific use, providing information about our economic life on an aggregated collective level. We ask the question whether there is a link between search volume data and financial market fluctuations on a weekly time scale. Both collective 'swarm intelligence' of Internet users and the group of financial market participants can be regarded as a complex system of many interacting subunits that react quickly to external changes. We find clear evidence that weekly transaction volumes of S&P 500 companies are correlated with weekly search volume of corresponding company names. Furthermore, we apply a recently introduced method for quantifying complex correlations in time series with which we find a clear tendency that search volume time series and transaction volume time series show recurring patterns.

  17. The selective adaptation of the alcoholics anonymous program by Gamblers Anonymous.

    Science.gov (United States)

    Browne, B R

    1991-09-01

    This paper is largely based on a year long observation study of Gamblers Anonymous and Alcoholics Anonymous meetings in northern California. The paper argues, contrary to popular assumption, that Gamblers Anonymous is significantly different from Alcoholics Anonymous. Differences, in members' consciousness for example, are discussed. The paper contends that although there is some12 step consciousness in G.A., the dominant consciousness ispage 17 consciousness. The significant differences are attributed to the selective adaptation of the Alcoholics Anonymous program. Several consequences of these differences, such as the central role of a language of the self in A.A. and not in G.A., are highlighted.

  18. Purpose-restricted Anonymous Mobile Communications Using Anonymous Signatures in Online Credential Systems

    DEFF Research Database (Denmark)

    Fathi, Hanane; Shin, SeongHan; Kobara, Kazukuni

    2010-01-01

    To avoid the risk of long-term storage of secrets on a portable device, an online credential system supports the roaming user in retrieving securely at various locations his private key and other material to generate anonymous signatures. The protocol proposed here allows a roaming mobile user...... to access anonymously services such as whistle blowing and net-counselling. Our approach: (1) allows a mobile user, remembering a short password, to anonymously and securely retrieve the credentials necessary for his anonymous communication without assuming a pre-established anonymous channel...

  19. 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.

  20. Anonymous women? Gamblers Anonymous and gender

    OpenAIRE

    Rogers, Jim

    2016-01-01

    One of the rapidly changing elements in gambling environments is the increasing participation of women in many forms of gambling, and the growing proportions of problem gamblers who are female. It is known that women who develop gambling problems differ from men in a range of ways:for example they are more likely to have co-morbidities such as anxiety and depression, and to gamble as an 'escape' from such co-occuring problems. Gamblers Anonymous (GA) has a number of meetings across New Zeala...

  1. 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)

  2. 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.

  3. Anonymous Connections and Onion Routing

    National Research Council Canada - National Science Library

    Syverson, Paul F; Goldschlag, David M; Reed, Michael G

    1997-01-01

    .... Unmodified Internet applications can use these anonymous connections by means of proxies. The proxies may also make communication anonymous by removing identifying information from the data stream...

  4. Anonymization of Court Decisions: Are Restrictions on the Right to Information in “Accordance with the Law”?

    Directory of Open Access Journals (Sweden)

    Gruodytė Edita

    2016-12-01

    Full Text Available In Lithuania rules for the anonymization of court decisions were introduced in 2005. These rules require automatic anonymization of all court decisions, which in the opinion of the authors violates the public interest to know and freedom of expression is unjustifiably restricted on behalf of the right to privacy. This issue covers two diametrically opposed human rights: the right to privacy and the right to information. The first question is how the balance between two equivalent rights could be reached. The second question is whether this regulation is in accordance with the law as it is established in the national Constitution and revealed by the Constitutional Court of the Republic of Lithuania and developed by the jurisprudence of the European Court of Human Rights. The authors conclude that the legislator is not empowered to delegate to the Judicial Council issues which are a matter of legal regulation and suggest possible solutions evaluating practice of the Court of Justice of the European Union, the European Court of Human Rights, and selected EU countries.

  5. An Anonymous User Authentication and Key Agreement Scheme Based on a Symmetric Cryptosystem in Wireless Sensor Networks.

    Science.gov (United States)

    Jung, Jaewook; Kim, Jiye; Choi, Younsung; Won, Dongho

    2016-08-16

    In wireless sensor networks (WSNs), a registered user can login to the network and use a user authentication protocol to access data collected from the sensor nodes. Since WSNs are typically deployed in unattended environments and sensor nodes have limited resources, many researchers have made considerable efforts to design a secure and efficient user authentication process. Recently, Chen et al. proposed a secure user authentication scheme using symmetric key techniques for WSNs. They claim that their scheme assures high efficiency and security against different types of attacks. After careful analysis, however, we find that Chen et al.'s scheme is still vulnerable to smart card loss attack and is susceptible to denial of service attack, since it is invalid for verification to simply compare an entered ID and a stored ID in smart card. In addition, we also observe that their scheme cannot preserve user anonymity. Furthermore, their scheme cannot quickly detect an incorrect password during login phase, and this flaw wastes both communication and computational overheads. In this paper, we describe how these attacks work, and propose an enhanced anonymous user authentication and key agreement scheme based on a symmetric cryptosystem in WSNs to address all of the aforementioned vulnerabilities in Chen et al.'s scheme. Our analysis shows that the proposed scheme improves the level of security, and is also more efficient relative to other related schemes.

  6. An Anonymous User Authentication and Key Agreement Scheme Based on a Symmetric Cryptosystem in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Jaewook Jung

    2016-08-01

    Full Text Available In wireless sensor networks (WSNs, a registered user can login to the network and use a user authentication protocol to access data collected from the sensor nodes. Since WSNs are typically deployed in unattended environments and sensor nodes have limited resources, many researchers have made considerable efforts to design a secure and efficient user authentication process. Recently, Chen et al. proposed a secure user authentication scheme using symmetric key techniques for WSNs. They claim that their scheme assures high efficiency and security against different types of attacks. After careful analysis, however, we find that Chen et al.’s scheme is still vulnerable to smart card loss attack and is susceptible to denial of service attack, since it is invalid for verification to simply compare an entered ID and a stored ID in smart card. In addition, we also observe that their scheme cannot preserve user anonymity. Furthermore, their scheme cannot quickly detect an incorrect password during login phase, and this flaw wastes both communication and computational overheads. In this paper, we describe how these attacks work, and propose an enhanced anonymous user authentication and key agreement scheme based on a symmetric cryptosystem in WSNs to address all of the aforementioned vulnerabilities in Chen et al.’s scheme. Our analysis shows that the proposed scheme improves the level of security, and is also more efficient relative to other related schemes.

  7. 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

  8. Consciousness as a process of queries and answers in architectures based on in situ representations

    NARCIS (Netherlands)

    van der Velde, F.; van der Velde, Frank

    2013-01-01

    Functional or access consciousness can be described as an ongoing dynamic process of queries and answers. Whenever we have an awareness of an object or its surroundings, it consists of the dynamic process that answers (implicit) queries like "What is the color or shape of the object?" or "What

  9. 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....

  10. 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...

  11. 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...

  12. Scoping review on search queries and social media for disease surveillance: a chronology of innovation.

    Science.gov (United States)

    Bernardo, Theresa Marie; Rajic, Andrijana; Young, Ian; Robiadek, Katie; Pham, Mai T; Funk, Julie A

    2013-07-18

    The threat of a global pandemic posed by outbreaks of influenza H5N1 (1997) and Severe Acute Respiratory Syndrome (SARS, 2002), both diseases of zoonotic origin, provoked interest in improving early warning systems and reinforced the need for combining data from different sources. It led to the use of search query data from search engines such as Google and Yahoo! as an indicator of when and where influenza was occurring. This methodology has subsequently been extended to other diseases and has led to experimentation with new types of social media for disease surveillance. The objective of this scoping review was to formally assess the current state of knowledge regarding the use of search queries and social media for disease surveillance in order to inform future work on early detection and more effective mitigation of the effects of foodborne illness. Structured scoping review methods were used to identify, characterize, and evaluate all published primary research, expert review, and commentary articles regarding the use of social media in surveillance of infectious diseases from 2002-2011. Thirty-two primary research articles and 19 reviews and case studies were identified as relevant. Most relevant citations were peer-reviewed journal articles (29/32, 91%) published in 2010-11 (28/32, 88%) and reported use of a Google program for surveillance of influenza. Only four primary research articles investigated social media in the context of foodborne disease or gastroenteritis. Most authors (21/32 articles, 66%) reported that social media-based surveillance had comparable performance when compared to an existing surveillance program. The most commonly reported strengths of social media surveillance programs included their effectiveness (21/32, 66%) and rapid detection of disease (21/32, 66%). The most commonly reported weaknesses were the potential for false positive (16/32, 50%) and false negative (11/32, 34%) results. Most authors (24/32, 75%) recommended that

  13. 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.

  14. 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

  15. 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...

  16. Anonymization of Court Orders

    DEFF Research Database (Denmark)

    Povlsen, Claus; Jongejan, Bart; Hansen, Dorte Haltrup

    We describe an anonymization tool that was commissioned by and specified together with Schultz, a publishing company specialized in Danish law related publications. Unavailability of training data and the need to guarantee compliance with pre-existing anonymization guidelines forced us to implement...... a tool using manually crafted rules. We used Bracmat, a programming language that is specialized in transforming tree data structures, to meet the requirement to pass the XML structure of the input document unscathed through the whole workflow. The tool attains a reassuringly good recall, makes almost...

  17. 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.

  18. Domainwise Web Page Optimization Based On Clustered Query Sessions Using Hybrid Of Trust And ACO For Effective Information Retrieval

    Directory of Open Access Journals (Sweden)

    Dr. Suruchi Chawla

    2015-08-01

    Full Text Available Abstract In this paper hybrid of Ant Colony OptimizationACO and trust has been used for domainwise web page optimization in clustered query sessions for effective Information retrieval. The trust of the web page identifies its degree of relevance in satisfying specific information need of the user. The trusted web pages when optimized using pheromone updates in ACO will identify the trusted colonies of web pages which will be relevant to users information need in a given domain. Hence in this paper the hybrid of Trust and ACO has been used on clustered query sessions for identifying more and more relevant number of documents in a given domain in order to better satisfy the information need of the user. Experiment was conducted on the data set of web query sessions to test the effectiveness of the proposed approach in selected three domains Academics Entertainment and Sports and the results confirm the improvement in the precision of search results.

  19. 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

  20. 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.

  1. Self-tallying quantum anonymous voting

    Science.gov (United States)

    Wang, Qingle; Yu, Chaohua; Gao, Fei; Qi, Haoyu; Wen, Qiaoyan

    2016-08-01

    Anonymous voting is a voting method of hiding the link between a vote and a voter, the context of which ranges from governmental elections to decision making in small groups like councils and companies. In this paper, we propose a quantum anonymous voting protocol assisted by two kinds of entangled quantum states. Particularly, we provide a mechanism of opening and permuting the ordered votes of all the voters in an anonymous manner; any party who is interested in the voting results can acquire a permutation copy and then obtains the voting result through a simple calculation. Unlike all previous quantum works on anonymous voting, our quantum anonymous protocol possesses the properties of privacy, self-tallying, nonreusability, verifiability, and fairness at the same time. In addition, we demonstrate that the entanglement of the quantum states used in our protocol makes an attack from an outside eavesdropper and inside dishonest voters impossible. We also generalize our protocol to execute the task of anonymous multiparty computation, such as anonymous broadcast and anonymous ranking.

  2. 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

  3. 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...

  4. A Web 2.0 Application for Executing Queries and Services on Climatic Data

    Science.gov (United States)

    Abad-Mota, S.; Ruckhaus, E.; Garboza, A.; Tepedino, G.

    2007-12-01

    aggregation, hourly, daily, monthly, so that they can be provided to the user at the desired level. This means that additional caution has to be exercised in query answering, in order to distinguish between primary and derived data. On the other hand, a Web 2.0 application is being designed to provide a front-end to the repository. This design focuses on two important aspects: the use of metadata structures, and the definition of collaborative Web 2.0 features that can be integrated to a project of this nature. Metadata descriptors include for a set of measurements, its quality, granularity and other dimension information. With these descriptors it is possible to establish relationships between different sets of measurements and provide scientists with efficient searching mechanisms that determine the related sets of measurements that contribute to a query answer. Unlike traditional applications for climatic data, our approach not only satisfies requirements of researchers specialized in this domain, but also those of anyone interested in this area; one of the objectives is to build an informal knowledge base that can be improved and consolidated with the usage of the system.

  5. 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

  6. 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

  7. 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.

  8. 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...

  9. 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.

  10. A Mechanism for Anonymous Credit Card Systems

    Science.gov (United States)

    Tamura, Shinsuke; Yanase, Tatsuro

    This paper proposes a mechanism for anonymous credit card systems, in which each credit card holder can conceal individual transactions from the credit card company, while enabling the credit card company to calculate the total expenditures of transactions of individual card holders during specified periods, and to identify card holders who executed dishonest transactions. Based on three existing mechanisms, i.e. anonymous authentication, blind signature and secure statistical data gathering, together with implicit transaction links proposed here, the proposed mechanism enables development of anonymous credit card systems without assuming any absolutely trustworthy entity like tamper resistant devices or organizations faithful both to the credit card company and card holders.

  11. A generative blog post retrieval model that uses query expansion based on external collections

    NARCIS (Netherlands)

    Weerkamp, W.; Balog, K.; de Rijke, M.; Su, K.-Y.; Su, J.; Wiebe, J.; Li, H.

    2009-01-01

    User generated content is characterized by short, noisy documents, with many spelling errors and unexpected language usage. To bridge the vocabulary gap between the user's information need and documents in a specific user generated content environment, the blogosphere, we apply a form of query

  12. Design of an On-Line Query Language for Full Text Patent Search.

    Science.gov (United States)

    Glantz, Richard S.

    The design of an English-like query language and an interactive computer environment for searching the full text of the U.S. patent collection are discussed. Special attention is paid to achieving a transparent user interface, to providing extremely broad search capabilities (including nested substitution classes, Kleene star events, and domain…

  13. Robust Query Processing for Personalized Information Access on the Semantic Web

    DEFF Research Database (Denmark)

    Dolog, Peter; Stuckenschmidt, Heiner; Wache, Holger

    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 RDF data as well as an implementation in terms of rewriting rules and explain its application in the context of e-learning...

  14. [Anonymous birth and neonaticide in Tyrol].

    Science.gov (United States)

    Danner, C; Pacher, M; Ambach, E; Brezinka, C

    2005-10-01

    In 2001 the Austrian government provided the legal means that formally enabled "anonymous birth": a woman can now give birth in any hospital in Austria without giving her name or insurance number, the baby is taken into care by social services and placed with adoptive parents. The cost of the hospital stay is covered from public funds. These measures were put into effect after some highly publicized cases of infant abandonment and neonaticide in Austria. In the mostly rural and small-town province of Tyrol province in western Austria (687,000 inhabitants, 7000 births per year) four cases of neonaticide were discovered in the years from 1996 to 2004. One child was abandoned inside a hospital. Since 2001 two women have made use of the "anonymous birth" option. Neither had had any pregnancy controls, both showed up at or near term with contractions. They delivered healthy infants that were then taken into care by local adoption services. Both women were extensively counselled by psychologists, social workers, medical and midwifery staff and both insisted on their original decision to remain anonymous. A few weeks later one of the women found herself at the centre of a criminal investigation for infanticide after anonymous letters were sent to family members insinuating she had done away with the child. Police stopped that investigation when hospital staff confirmed that the woman had had an "anonymous" delivery. Despite the option of legal "anonymous" birth free of charge in modern hospitals there are still cases of infant abandonment and neonaticide in Austria. It is proposed that the women who opt for anonymous birth may not be the women who would otherwise kill their babies. Instead, it appears that the women opted for anonymity to escape the probably well-intentioned but overbearing attention of their families and of social services. It is doubtful that the option of anonymous birth will lead to a complete disappearance of infanticide and infant abandonment in

  15. Anonymous quantum communications using the quantum one-time pad

    International Nuclear Information System (INIS)

    Wang, Qing-Le; Gao, Fei-; Liu, Bin; Song, Ting-Ting; Wen, Qiao-Yan

    2015-01-01

    We present the first quantum secure communication protocol for an anonymous receiver without the assistance of anonymous entanglement. In previous works, if a public sender wants to send quantum messages to a chosen receiver while protecting the identity of the receiver from others, all participants should cooperate first to construct the entanglement between the sender and the anonymous receiver. This is the most important process in anonymous quantum communications. With anonymous entanglement, the sender can communicate quantum messages to the anonymous receiver by applying teleportation protocols. In contrast, our protocol is novel and achieves communication of quantum messages directly from the public sender to the anonymous receiver based on the quantum one-time pad and current achievements. Notably, the anonymity of the receiver, as well as the privacy of the quantum messages, is perfectly protected with the exception of an exponentially small probability in our protocol. (paper)

  16. Security Analysis of Accountable Anonymous Group Communication in Dissent

    Science.gov (United States)

    2013-01-31

    instance, group discussion forums or instant messaging. Misbehaving users may abuse this anonymity to disrupt communication, however, and existing...Abstract Users often wish to communicate anonymously on the Internet using, for instance, group discussion forums or instant messaging. Misbehaving users may...personal reprisal (Stein 2003). Yet anonymity makes it difficult to trace or exclude misbehaving participants (Davenport 2002). Online proto- cols

  17. 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

  18. 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...

  19. 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....

  20. 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...

  1. 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

  2. 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...

  3. 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

  4. Alcoholics anonymous, other 12-step movements and psychotherapy in the US population, 1990.

    Science.gov (United States)

    Room, R; Greenfield, T

    1993-04-01

    Based on the 1990 US National Alcohol Survey, this note provides the first available comprehensive findings on self-reported utilization of a variety of sources of personal support and counselling for alcohol and other problems. Respondents were queried about lifetime attendance and number of times they went to identified sources of help in the prior year. Twelve-step groups included Alcoholics Anonymous, Al-Anon, Adult Children of Alcoholics, and other non-alcohol-oriented groups like Gamblers Anonymous, Narcotics Anonymous, and Overeaters Anonymous; additional questions inquired about support or therapy groups and individual counselling for non-alcohol problems. Of the US adult population, 9% have been to an AA meeting at some time, 3.6% in the prior year, only about one-third of these for problems of their own. About half these percentages, mostly women, have attended Al-Anon. Of the same population, 13.3% indicate ever attending a 12-step meeting (including non-alcohol-oriented groups), 5.3% in the last year. During the prior year a further 2.1% used other support/therapy groups and 5.5% sought individual counselling/therapy for personal problems other than alcohol. In contrast to this high reported utilization, only 4.9% (ever) and 2.3% (12-months) reported going to anyone including AA for a problem (of their own) related to drinking.

  5. 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.

  6. Application and advantages of the connector "and possibly" in bipolar queries on Gefred model

    Directory of Open Access Journals (Sweden)

    Fabián Castiblanco R.

    2016-06-01

    Full Text Available Fuzzy databases have been implemented in corporate and organizational level as an efficient and effective tool to carry out searches with values that can be vague, unknown, incomplete or null. In the same way, developments about bipolarity have allowed user to raise more flexible queries in terms of their proximity to natural language. The aim of this paper is to implement the fuzzy operator “and possibly” proposed by the theory of bipolar queries, in the Generalized Model of Fuzzy Relational Databases (Gefred. With this aim in mind, in the first part it is addressed the theoretical aspects about bipolarity and the Gefred model that allow to think about an integration between both theories. Then, through an application, it is proposed the needed procedures and the emerging advantages of use of fuzzy operator.

  7. 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.

  8. Shark: SQL and Analytics with Cost-Based Query Optimization on Coarse-Grained Distributed Memory

    Science.gov (United States)

    2014-01-13

    RDBMS and contains a database (often MySQL or Derby) with a namespace for tables, table metadata and partition information. Table data is stored in an...serialization/deserialization) Java interface implementations with corresponding object inspectors. The Hive driver controls the processing of queries, coordinat...native API, RDD operations are invoked through a functional interface similar to DryadLINQ [32] in Scala, Java or Python. For example, the Scala code for

  9. Relative expressive power of navigational querying on graphs using transitive closure

    OpenAIRE

    Surinx, Dimitri; Fletcher, George H. L.; Gyssens, Marc; Leinders, Dirk; Van den Bussche, Jan; Van Gucht, Dirk; Vansummeren, Stijn; Wu, Yuqing

    2015-01-01

    Motivated by both established and new applications, we study navigational query languages for graphs (binary relations). The simplest language has only the two operators union and composition, together with the identity relation. We make more powerful languages by adding any of the following operators: intersection; set difference; projection; coprojection; converse; transitive closure; and the diversity relation. All these operators map binary relations to binary relations. We compare the ex...

  10. 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...

  11. Querying phenotype-genotype relationships on patient datasets using semantic web technology: the example of Cerebrotendinous xanthomatosis.

    Science.gov (United States)

    Taboada, María; Martínez, Diego; Pilo, Belén; Jiménez-Escrig, Adriano; Robinson, Peter N; Sobrido, María J

    2012-07-31

    Semantic Web technology can considerably catalyze translational genetics and genomics research in medicine, where the interchange of information between basic research and clinical levels becomes crucial. This exchange involves mapping abstract phenotype descriptions from research resources, such as knowledge databases and catalogs, to unstructured datasets produced through experimental methods and clinical practice. This is especially true for the construction of mutation databases. This paper presents a way of harmonizing abstract phenotype descriptions with patient data from clinical practice, and querying this dataset about relationships between phenotypes and genetic variants, at different levels of abstraction. Due to the current availability of ontological and terminological resources that have already reached some consensus in biomedicine, a reuse-based ontology engineering approach was followed. The proposed approach uses the Ontology Web Language (OWL) to represent the phenotype ontology and the patient model, the Semantic Web Rule Language (SWRL) to bridge the gap between phenotype descriptions and clinical data, and the Semantic Query Web Rule Language (SQWRL) to query relevant phenotype-genotype bidirectional relationships. The work tests the use of semantic web technology in the biomedical research domain named cerebrotendinous xanthomatosis (CTX), using a real dataset and ontologies. A framework to query relevant phenotype-genotype bidirectional relationships is provided. Phenotype descriptions and patient data were harmonized by defining 28 Horn-like rules in terms of the OWL concepts. In total, 24 patterns of SWQRL queries were designed following the initial list of competency questions. As the approach is based on OWL, the semantic of the framework adapts the standard logical model of an open world assumption. This work demonstrates how semantic web technologies can be used to support flexible representation and computational inference mechanisms

  12. 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.

  13. An Anonymous Credit Card System

    Science.gov (United States)

    Androulaki, Elli; Bellovin, Steven

    Credit cards have many important benefits; however, these same benefits often carry with them many privacy concerns. In particular, the need for users to be able to monitor their own transactions, as well as bank’s need to justify its payment requests from cardholders, entitle the latter to maintain a detailed log of all transactions its credit card customers were involved in. A bank can thus build a profile of each cardholder even without the latter’s consent. In this paper, we present a practical and accountable anonymous credit system based on ecash, with a privacy preserving mechanism for error correction and expense-reporting.

  14. 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

  15. Anon-Pass: Practical Anonymous Subscriptions.

    Science.gov (United States)

    Lee, Michael Z; Dunn, Alan M; Katz, Jonathan; Waters, Brent; Witchel, Emmett

    2013-12-31

    We present the design, security proof, and implementation of an anonymous subscription service. Users register for the service by providing some form of identity, which might or might not be linked to a real-world identity such as a credit card, a web login, or a public key. A user logs on to the system by presenting a credential derived from information received at registration. Each credential allows only a single login in any authentication window, or epoch . Logins are anonymous in the sense that the service cannot distinguish which user is logging in any better than random guessing. This implies unlinkability of a user across different logins. We find that a central tension in an anonymous subscription service is the service provider's desire for a long epoch (to reduce server-side computation) versus users' desire for a short epoch (so they can repeatedly "re-anonymize" their sessions). We balance this tension by having short epochs, but adding an efficient operation for clients who do not need unlinkability to cheaply re-authenticate themselves for the next time period. We measure performance of a research prototype of our protocol that allows an independent service to offer anonymous access to existing services. We implement a music service, an Android-based subway-pass application, and a web proxy, and show that adding anonymity adds minimal client latency and only requires 33 KB of server memory per active user.

  16. The Anonymization Protection Algorithm Based on Fuzzy Clustering for the Ego of Data in the Internet of Things

    Directory of Open Access Journals (Sweden)

    Mingshan Xie

    2017-01-01

    Full Text Available In order to enhance the enthusiasm of the data provider in the process of data interaction and improve the adequacy of data interaction, we put forward the concept of the ego of data and then analyzed the characteristics of the ego of data in the Internet of Things (IOT in this paper. We implement two steps of data clustering for the Internet of things; the first step is the spatial location of adjacent fuzzy clustering, and the second step is the sampling time fuzzy clustering. Equivalent classes can be obtained through the two steps. In this way we can make the data with layout characteristics to be classified into different equivalent classes, so that the specific location information of the data can be obscured, the layout characteristics of tags are eliminated, and ultimately anonymization protection would be achieved. The experimental results show that the proposed algorithm can greatly improve the efficiency of protection of the data in the interaction with others in the incompletely open manner, without reducing the quality of anonymization and enhancing the information loss. The anonymization data set generated by this method has better data availability, and this algorithm can effectively improve the security of data exchange.

  17. 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.

  18. 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...

  19. 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.

  20. 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...

  1. 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.

  2. 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....

  3. Anonymity as an Instructional Scaffold in Peer Assessment: Its Effects on Peer Feedback Quality and Evolution in Students' Perceptions about Peer Assessment Skills

    Science.gov (United States)

    Rotsaert, Tijs; Panadero, Ernesto; Schellens, Tammy

    2018-01-01

    Although previous research has indicated that providing anonymity is an effective way to create a safe peer assessment setting, continuously ensuring anonymity prevents students from experiencing genuine two-way interactive feedback dialogues. The present study investigated how installing a transitional approach from an anonymous to a…

  4. Scalable and Anonymous Group Communication with MTor

    Directory of Open Access Journals (Sweden)

    Lin Dong

    2016-04-01

    Full Text Available This paper presents MTor, a low-latency anonymous group communication system. We construct MTor as an extension to Tor, allowing the construction of multi-source multicast trees on top of the existing Tor infrastructure. MTor does not depend on an external service to broker the group communication, and avoids central points of failure and trust. MTor’s substantial bandwidth savings and graceful scalability enable new classes of anonymous applications that are currently too bandwidth-intensive to be viable through traditional unicast Tor communication-e.g., group file transfer, collaborative editing, streaming video, and real-time audio conferencing.

  5. 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.

  6. Adverse Reactions Associated With Cannabis Consumption as Evident From Search Engine Queries.

    Science.gov (United States)

    Yom-Tov, Elad; Lev-Ran, Shaul

    2017-10-26

    Cannabis is one of the most widely used psychoactive substances worldwide, but adverse drug reactions (ADRs) associated with its use are difficult to study because of its prohibited status in many countries. Internet search engine queries have been used to investigate ADRs in pharmaceutical drugs. In this proof-of-concept study, we tested whether these queries can be used to detect the adverse reactions of cannabis use. We analyzed anonymized queries from US-based users of Bing, a widely used search engine, made over a period of 6 months and compared the results with the prevalence of cannabis use as reported in the US National Survey on Drug Use in the Household (NSDUH) and with ADRs reported in the Food and Drug Administration's Adverse Drug Reporting System. Predicted prevalence of cannabis use was estimated from the fraction of people making queries about cannabis, marijuana, and 121 additional synonyms. Predicted ADRs were estimated from queries containing layperson descriptions to 195 ICD-10 symptoms list. Our results indicated that the predicted prevalence of cannabis use at the US census regional level reaches an R 2 of .71 NSDUH data. Queries for ADRs made by people who also searched for cannabis reveal many of the known adverse effects of cannabis (eg, cough and psychotic symptoms), as well as plausible unknown reactions (eg, pyrexia). These results indicate that search engine queries can serve as an important tool for the study of adverse reactions of illicit drugs, which are difficult to study in other settings. ©Elad Yom-Tov, Shaul Lev-Ran. Originally published in JMIR Public Health and Surveillance (http://publichealth.jmir.org), 26.10.2017.

  7. Moving Spatial Keyword Queries

    DEFF Research Database (Denmark)

    Wu, Dingming; Yiu, Man Lung; Jensen, Christian S.

    2013-01-01

    propose two algorithms for computing safe zones that guarantee correct results at any time and that aim to optimize the server-side computation as well as the communication between the server and the client. We exploit tight and conservative approximations of safe zones and aggressive computational space...... text data. State-of-the-art solutions for moving queries employ safe zones that guarantee the validity of reported results as long as the user remains within the safe zone associated with a result. However, existing safe-zone methods focus solely on spatial locations and ignore text relevancy. We...... pruning. We present techniques that aim to compute the next safe zone efficiently, and we present two types of conservative safe zones that aim to reduce the communication cost. Empirical studies with real data suggest that the proposals are efficient. To understand the effectiveness of the proposed safe...

  8. [On the seasonality of dermatoses: a retrospective analysis of search engine query data depending on the season].

    Science.gov (United States)

    Köhler, M J; Springer, S; Kaatz, M

    2014-09-01

    The volume of search engine queries about disease-relevant items reflects public interest and correlates with disease prevalence as proven by the example of flu (influenza). Other influences include media attention or holidays. The present work investigates if the seasonality of prevalence or symptom severity of dermatoses correlates with search engine query data. The relative weekly volume of dermatological relevant search terms was assessed by the online tool Google Trends for the years 2009-2013. For each item, the degree of seasonality was calculated via frequency analysis and a geometric approach. Many dermatoses show a marked seasonality, reflected by search engine query volumes. Unexpected seasonal variations of these queries suggest a previously unknown variability of the respective disease prevalence. Furthermore, using the example of allergic rhinitis, a close correlation of search engine query data with actual pollen count can be demonstrated. In many cases, search engine query data are appropriate to estimate seasonal variability in prevalence of common dermatoses. This finding may be useful for real-time analysis and formation of hypotheses concerning pathogenetic or symptom aggravating mechanisms and may thus contribute to improvement of diagnostics and prevention of skin diseases.

  9. A Topological Framework for Interactive Queries on 3D Models in the Web

    Directory of Open Access Journals (Sweden)

    Mauro Figueiredo

    2014-01-01

    Full Text Available Several technologies exist to create 3D content for the web. With X3D, WebGL, and X3DOM, it is possible to visualize and interact with 3D models in a web browser. Frequently, three-dimensional objects are stored using the X3D file format for the web. However, there is no explicit topological information, which makes it difficult to design fast algorithms for applications that require adjacency and incidence data. This paper presents a new open source toolkit TopTri (Topological model for Triangle meshes for Web3D servers that builds the topological model for triangular meshes of manifold or nonmanifold models. Web3D client applications using this toolkit make queries to the web server to get adjacent and incidence information of vertices, edges, and faces. This paper shows the application of the topological information to get minimal local points and iso-lines in a 3D mesh in a web browser. As an application, we present also the interactive identification of stalactites in a cave chamber in a 3D web browser. Several tests show that even for large triangular meshes with millions of triangles, the adjacency and incidence information is returned in real time making the presented toolkit appropriate for interactive Web3D applications.

  10. A Topological Framework for Interactive Queries on 3D Models in the Web

    Science.gov (United States)

    Figueiredo, Mauro; Rodrigues, José I.; Silvestre, Ivo; Veiga-Pires, Cristina

    2014-01-01

    Several technologies exist to create 3D content for the web. With X3D, WebGL, and X3DOM, it is possible to visualize and interact with 3D models in a web browser. Frequently, three-dimensional objects are stored using the X3D file format for the web. However, there is no explicit topological information, which makes it difficult to design fast algorithms for applications that require adjacency and incidence data. This paper presents a new open source toolkit TopTri (Topological model for Triangle meshes) for Web3D servers that builds the topological model for triangular meshes of manifold or nonmanifold models. Web3D client applications using this toolkit make queries to the web server to get adjacent and incidence information of vertices, edges, and faces. This paper shows the application of the topological information to get minimal local points and iso-lines in a 3D mesh in a web browser. As an application, we present also the interactive identification of stalactites in a cave chamber in a 3D web browser. Several tests show that even for large triangular meshes with millions of triangles, the adjacency and incidence information is returned in real time making the presented toolkit appropriate for interactive Web3D applications. PMID:24977236

  11. 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)

  12. jQuery cookbook

    CERN Document Server

    2010-01-01

    jQuery simplifies building rich, interactive web frontends. Getting started with this JavaScript library is easy, but it can take years to fully realize its breadth and depth; this cookbook shortens the learning curve considerably. With these recipes, you'll learn patterns and practices from 19 leading developers who use jQuery for everything from integrating simple components into websites and applications to developing complex, high-performance user interfaces. Ideal for newcomers and JavaScript veterans alike, jQuery Cookbook starts with the basics and then moves to practical use cases w

  13. 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...

  14. 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

  15. Anonymous Transactions in Computer Networks

    Science.gov (United States)

    Dolev, Shlomi; Kopeetsky, Marina

    We present schemes for providing anonymous transactions while privacy and anonymity are preserved, providing user anonymous authentication in distributed networks such as the Internet. We first present a practical scheme for anonymous transactions while the transaction resolution is assisted by a Trusted Authority. This practical scheme is extended to a theoretical scheme where a Trusted Authority is not involved in the transaction resolution. Given an authority that generates for each player hard to produce evidence EVID (e. g., problem instance with or without a solution) to each player, the identity of a user U is defined by the ability to prove possession of said evidence. We use Zero-Knowledge proof techniques to repeatedly identify U by providing a proof that U has evidence EVID, without revealing EVID, therefore avoiding identity theft.

  16. 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....

  17. Really not god: Secularization and pragmatism in Gamblers Anonymous.

    Science.gov (United States)

    Browne, B R

    1994-09-01

    The paper argues that despite maintaining the image of a twelve-step organization, the central theme of the history of Gamblers Anonymous (GA) in the United States is the increasing secularization of the program of the recovery. The paper documents the increasing secularization and pragmatism of Gamblers Anonymous, as reflected in key documents, despite the spiritual vision of its founding member. The author speculates on why Gamblers Anonymous took a secularized development path. Further research is called for.

  18. Anonymity and Openness in Donor Conception: the New Danish Model

    DEFF Research Database (Denmark)

    Herrmann, Janne Rothmar

    2013-01-01

    model in donor conception which offers women/couples a choice of anonymity or openness in donation.This paper is based on my talk on June 20, 2013 at London School of Economics at the conference “New Families and Genetic Identities: Developments in law, policy and research” organised by the Morgan...... bank is based in Denmark and consequently anonymous sperm is also exported abroad, even into jurisdictions where anonymity is banned illegal. This commentary traces the raison d’être of anonymity in Danish law, accounts for the legal framework for the internet sale of sperm and examines the new Danish...

  19. Utility-preserving anonymization for health data publishing.

    Science.gov (United States)

    Lee, Hyukki; Kim, Soohyung; Kim, Jong Wook; Chung, Yon Dohn

    2017-07-11

    Publishing raw electronic health records (EHRs) may be considered as a breach of the privacy of individuals because they usually contain sensitive information. A common practice for the privacy-preserving data publishing is to anonymize the data before publishing, and thus satisfy privacy models such as k-anonymity. Among various anonymization techniques, generalization is the most commonly used in medical/health data processing. Generalization inevitably causes information loss, and thus, various methods have been proposed to reduce information loss. However, existing generalization-based data anonymization methods cannot avoid excessive information loss and preserve data utility. We propose a utility-preserving anonymization for privacy preserving data publishing (PPDP). To preserve data utility, the proposed method comprises three parts: (1) utility-preserving model, (2) counterfeit record insertion, (3) catalog of the counterfeit records. We also propose an anonymization algorithm using the proposed method. Our anonymization algorithm applies full-domain generalization algorithm. We evaluate our method in comparison with existence method on two aspects, information loss measured through various quality metrics and error rate of analysis result. With all different types of quality metrics, our proposed method show the lower information loss than the existing method. In the real-world EHRs analysis, analysis results show small portion of error between the anonymized data through the proposed method and original data. We propose a new utility-preserving anonymization method and an anonymization algorithm using the proposed method. Through experiments on various datasets, we show that the utility of EHRs anonymized by the proposed method is significantly better than those anonymized by previous approaches.

  20. 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

  1. Anonymous publication of sensitive transactional data

    KAUST Repository

    Ghinita, Gabriel; Kalnis, Panos; Tao, Yufei

    2011-01-01

    Existing research on privacy-preserving data publishing focuses on relational data: in this context, the objective is to enforce privacy-preserving paradigms, such as k-anonymity and ℓ-diversity, while minimizing the information loss incurred in the anonymizing process (i.e., maximize data utility). Existing techniques work well for fixed-schema data, with low dimensionality. Nevertheless, certain applications require privacy-preserving publishing of transactional data (or basket data), which involve hundreds or even thousands of dimensions, rendering existing methods unusable. We propose two categories of novel anonymization methods for sparse high-dimensional data. The first category is based on approximate nearest-neighbor (NN) search in high-dimensional spaces, which is efficiently performed through locality-sensitive hashing (LSH). In the second category, we propose two data transformations that capture the correlation in the underlying data: 1) reduction to a band matrix and 2) Gray encoding-based sorting. These representations facilitate the formation of anonymized groups with low information loss, through an efficient linear-time heuristic. We show experimentally, using real-life data sets, that all our methods clearly outperform existing state of the art. Among the proposed techniques, NN-search yields superior data utility compared to the band matrix transformation, but incurs higher computational overhead. The data transformation based on Gray code sorting performs best in terms of both data utility and execution time. © 2006 IEEE.

  2. Botnet detection and prevention in anonymous networks

    NARCIS (Netherlands)

    Kuhnert, Katharina; Steinberger, Jessica; Baier, Harald

    Botnets are a major threat to the Internet landscape and have been responsible for large scale distributed attacks on online services. To make take down measures more difficult, Botnet operators started to incorporate anonymous networks into their software to protect their users and their Botnets.

  3. Anonymous publication of sensitive transactional data

    KAUST Repository

    Ghinita, Gabriel

    2011-02-01

    Existing research on privacy-preserving data publishing focuses on relational data: in this context, the objective is to enforce privacy-preserving paradigms, such as k-anonymity and ℓ-diversity, while minimizing the information loss incurred in the anonymizing process (i.e., maximize data utility). Existing techniques work well for fixed-schema data, with low dimensionality. Nevertheless, certain applications require privacy-preserving publishing of transactional data (or basket data), which involve hundreds or even thousands of dimensions, rendering existing methods unusable. We propose two categories of novel anonymization methods for sparse high-dimensional data. The first category is based on approximate nearest-neighbor (NN) search in high-dimensional spaces, which is efficiently performed through locality-sensitive hashing (LSH). In the second category, we propose two data transformations that capture the correlation in the underlying data: 1) reduction to a band matrix and 2) Gray encoding-based sorting. These representations facilitate the formation of anonymized groups with low information loss, through an efficient linear-time heuristic. We show experimentally, using real-life data sets, that all our methods clearly outperform existing state of the art. Among the proposed techniques, NN-search yields superior data utility compared to the band matrix transformation, but incurs higher computational overhead. The data transformation based on Gray code sorting performs best in terms of both data utility and execution time. © 2006 IEEE.

  4. Changing spousal roles and their effect on recovery in gamblers anonymous: GamAnon, social support, wives and husbands.

    Science.gov (United States)

    Ferentzy, Peter; Skinner, Wayne; Antze, Paul

    2010-09-01

    This paper examines changing spousal roles and their effects upon recovery in Gamblers Anonymous (GA). It is based upon a qualitative study designed to gage uniformity as well as variations in approaches to recovery in GA. Interviews were conducted with 39 GA members (26 men, 13 women; mean age 56.5 years). Though the study was based in the Toronto area, only 13 interviews involved participants from that region. Phone interviews were conducted with GA members from various regions of both Canada and the US. GamAnon, GA's sister fellowship, has been designed for anyone affected seriously by someone's gambling problem. In practice, GamAnon comprises mostly women--spouses of male GA members--who traditionally have taken a keen interest in the ways in which their husbands achieve and maintain abstinence from gambling. Changing spousal roles have led to fewer women joining GamAnon, as many opt instead to part with troubled spouses. As well, more women are attending GA than in the past, typically with husbands who are disinclined to join GamAnon. All of this has drastically altered how GA members pursue recovery. These changes and their implications are discussed.

  5. 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...

  6. An Applet-based Anonymous Distributed Computing System.

    Science.gov (United States)

    Finkel, David; Wills, Craig E.; Ciaraldi, Michael J.; Amorin, Kevin; Covati, Adam; Lee, Michael

    2001-01-01

    Defines anonymous distributed computing systems and focuses on the specifics of a Java, applet-based approach for large-scale, anonymous, distributed computing on the Internet. Explains the possibility of a large number of computers participating in a single computation and describes a test of the functionality of the system. (Author/LRW)

  7. 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

  8. 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.

  9. Querying and Mining Strings Made Easy

    KAUST Repository

    Sahli, Majed

    2017-10-13

    With the advent of large string datasets in several scientific and business applications, there is a growing need to perform ad-hoc analysis on strings. Currently, strings are stored, managed, and queried using procedural codes. This limits users to certain operations supported by existing procedural applications and requires manual query planning with limited tuning opportunities. This paper presents StarQL, a generic and declarative query language for strings. StarQL is based on a native string data model that allows StarQL to support a large variety of string operations and provide semantic-based query optimization. String analytic queries are too intricate to be solved on one machine. Therefore, we propose a scalable and efficient data structure that allows StarQL implementations to handle large sets of strings and utilize large computing infrastructures. Our evaluation shows that StarQL is able to express workloads of application-specific tools, such as BLAST and KAT in bioinformatics, and to mine Wikipedia text for interesting patterns using declarative queries. Furthermore, the StarQL query optimizer shows an order of magnitude reduction in query execution time.

  10. Patient Perspectives on Sharing Anonymized Personal Health Data Using a Digital System for Dynamic Consent and Research Feedback: A Qualitative Study

    Science.gov (United States)

    Whitley, Edgar A; Lund, David; Kaye, Jane

    2016-01-01

    Background Electronic health records are widely acknowledged to provide an important opportunity to anonymize patient-level health care data and collate across populations to support research. Nonetheless, in the wake of public and policy concerns about security and inappropriate use of data, conventional approaches toward data governance may no longer be sufficient to respect and protect individual privacy. One proposed solution to improve transparency and public trust is known as Dynamic Consent, which uses information technology to facilitate a more explicit and accessible opportunity to opt out. In this case, patients can tailor preferences about whom they share their data with and can change their preferences reliably at any time. Furthermore, electronic systems provide opportunities for informing patients about data recipients and the results of research to which their data have contributed. Objective To explore patient perspectives on the use of anonymized health care data for research purposes. To evaluate patient perceptions of a Dynamic Consent model and electronic system to enable and implement ongoing communication and collaboration between patients and researchers. Methods A total of 26 qualitative interviews and three focus groups were conducted that included a video presentation explaining the reuse of anonymized electronic patient records for research. Slides and tablet devices were used to introduce the Dynamic Consent system for discussion. A total of 35 patients with chronic rheumatic disease with varying levels of illness and social deprivation were recruited from a rheumatology outpatient clinic; 5 participants were recruited from a patient and public involvement health research network. Results Patients were supportive of sharing their anonymized electronic patient record for research, but noted a lack of transparency and awareness around the use of data, making it difficult to secure public trust. While there were general concerns about

  11. Patient Perspectives on Sharing Anonymized Personal Health Data Using a Digital System for Dynamic Consent and Research Feedback: A Qualitative Study.

    Science.gov (United States)

    Spencer, Karen; Sanders, Caroline; Whitley, Edgar A; Lund, David; Kaye, Jane; Dixon, William Gregory

    2016-04-15

    Electronic health records are widely acknowledged to provide an important opportunity to anonymize patient-level health care data and collate across populations to support research. Nonetheless, in the wake of public and policy concerns about security and inappropriate use of data, conventional approaches toward data governance may no longer be sufficient to respect and protect individual privacy. One proposed solution to improve transparency and public trust is known as Dynamic Consent, which uses information technology to facilitate a more explicit and accessible opportunity to opt out. In this case, patients can tailor preferences about whom they share their data with and can change their preferences reliably at any time. Furthermore, electronic systems provide opportunities for informing patients about data recipients and the results of research to which their data have contributed. To explore patient perspectives on the use of anonymized health care data for research purposes. To evaluate patient perceptions of a Dynamic Consent model and electronic system to enable and implement ongoing communication and collaboration between patients and researchers. A total of 26 qualitative interviews and three focus groups were conducted that included a video presentation explaining the reuse of anonymized electronic patient records for research. Slides and tablet devices were used to introduce the Dynamic Consent system for discussion. A total of 35 patients with chronic rheumatic disease with varying levels of illness and social deprivation were recruited from a rheumatology outpatient clinic; 5 participants were recruited from a patient and public involvement health research network. Patients were supportive of sharing their anonymized electronic patient record for research, but noted a lack of transparency and awareness around the use of data, making it difficult to secure public trust. While there were general concerns about detrimental consequences of data falling

  12. 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...

  13. 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.

  14. “We are Anonymous.” Anonymity in the Public Sphere – Challenges of Free and Open Communication

    Directory of Open Access Journals (Sweden)

    Saskia Sell

    2013-05-01

    Full Text Available Anonymity, the stealth mode of public communication, challenges different actors who deal with freedom of communication issues in their day to day life – be it professional journalists, information and communication scientists, technicians or political activists. This article aims to deliver theoretical background on the concept of anonymity on the macro-level, as well as to shed light on how different communicators deal with anonymity on the micro-level. Based on the example of the Anonymous movement, communicative actions are put in relation to media technological artifacts and their surrounding media environment with a focus on journalistic practice and public response to the phenomenon. The analysis concludes with the need for a preservation of options for anonymous public communication as a dimension of freedom of communication after carefully considering both the advantages and the potential risks connected to that mode of private-public communication.

  15. Examination of anonymous canine faecal samples provides data on endoparasite prevalence rates in dogs for comparative studies.

    Science.gov (United States)

    Hinney, Barbara; Gottwald, Michaela; Moser, Jasmine; Reicher, Bianca; Schäfer, Bhavapriya Jasmin; Schaper, Roland; Joachim, Anja; Künzel, Frank

    2017-10-15

    Several endoparasites of dogs cannot only be detrimental to their primary host but might also represent a threat to human health because of their zoonotic potential. Due to their high dog population densities, metropolitan areas can be highly endemic for such parasites. We aimed to estimate the prevalence of endoparasites in dogs in the Austrian capital of Vienna by examining a representative number of canine faecal samples and to compare the prevalences with two neighbouring peri-urban and rural regions. In addition we analysed whether the density of dog populations and cleanliness of dog zones correlated with parasite occurrence. We collected 1001 anonymous faecal samples from 55 dog zones from all 23 districts of the federal state of Vienna, as well as 480 faecal samples from the Mödling district and Wolkersdorf with a peri-urban and rural character, respectively. Faeces were examined by flotation and by Baermann technique. Additionally we evaluated 292 Viennese, 102 peri-urban and 50 rural samples for Giardia and Cryptosporidium by GiardiaFASTest ® and CryptoFASTest ® . Samples from "clean" dog zones were compared to samples from "dirty" zones. The infection rate of Toxocara was surprisingly low, ranging from 0.6% to 1.9%. Trichuris was the most frequent helminth (1.8-7.5%) and Giardia the most frequent protozoan (4.0-10.8%). Ancylostomatidae, Crenosoma, Capillaria, Taeniidae, Cystoisospora and Sarcocystis were found in 1.8-2.2%, 0-0.9%, 0-0.9%, 0-0.6%, 0.3-3.1% and 0-0.6% of the samples, respectively. Samples from "dirty" dog zones in Vienna showed a significantly higher rate of parasites overall (p=0.003) and of Trichuris (p=0.048) compared to samples from "clean" dog zones. There were no statistically significant differences in densely vs. less densely populated areas of Vienna. Samples from the rural region of Wolkersdorf had significantly higher overall parasite, Trichuris and Cystoisospora prevalences than the peri-urban Mödling district and Vienna (p

  16. Are anonymous evaluations a better assessment of faculty teaching performance? A comparative analysis of open and anonymous evaluation processes.

    Science.gov (United States)

    Afonso, Nelia M; Cardozo, Lavoisier J; Mascarenhas, Oswald A J; Aranha, Anil N F; Shah, Chirag

    2005-01-01

    We compared teaching performance of medical school faculty using anonymous evaluations and open evaluations (in which the evaluator was not anonymous) and examined barriers to open evaluation. Residents and medical students evaluated faculty using an open evaluation instrument in which their identity was indicated in the evaluation. Following this, they completed anonymous evaluation on the same faculty members. Aggregate outcomes using the two evaluation systems were compared. Outcomes by group of evaluators (residents and students) were analyzed. Trainees were also asked to rate the barriers to the open evaluation process. A statistically significant difference between the open and anonymous evaluations was noted across all items, with faculty receiving lower scores on the anonymous evaluations. The mean score for all the items on the open evaluations was 4.45 +/- 0.65, compared to mean score of 4.07 +/- 0.80 on the anonymous evaluations. There was also a statistically significant difference between open and anonymous evaluations in five clinical teaching domains that were evaluated individually. Residents perceived that the three most common barriers to optimal evaluation were an apprehension of possible encounters with the same attending physician in the future, destruction of working relationships with the attending, and a feeling of frustration with the evaluation system. The evaluation of faculty teaching performance is complex. Most academic medical centers use the open evaluation format. This study supports the case for the use of the anonymous evaluation method as a more accurate reflection of teaching performance.

  17. 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....

  18. Anonymity, ethics and credibility in the blogosphere and on Twitter: gastronomic criticism in “Alhos, passas & maçãs” and in @carapuceiro

    Directory of Open Access Journals (Sweden)

    Renata Maria do Amaral

    2012-07-01

    Full Text Available This article intends to understand the anonymous restaurant critic currently made on the Internet, based on the cases of the Alhos, passas & maçãs blog and the @carapuceiro Twitter. Before considered as personal diaries or means of communication among friends, today blogs and social networks have no limits – and, when used to criticize restaurants negatively, its impact reaches unpremeditated boundaries, including reactions of chefs and journalists themselves. At the same time that these tools extend the possibilities of subjective comments written by ordinary people, without a degree in journalism, the press loses credibility by choosing to criticize in a courteous way, submitting itself to the invitations sent by press offices and to the “cordial journalism”.

  19. 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.

  20. Atheists, agnostics and Alcoholics Anonymous.

    Science.gov (United States)

    Tonigan, J Scott; Miller, W R; Schermer, Carol

    2002-09-01

    In spite of the strong emphasis in AA on spiritual beliefs and practices, findings are mixed about the importance of such beliefs in predicting AA affiliation. This study of the Project MATCH outpatient (N = 952) and aftercare (N = 774) samples tested three hypotheses about the role of client God belief and subsequent AA attendance and benefit, taking into account that some individuals may, in fact, deny the existence of a God. Longitudinal analyses were conducted (N = 1,526) investigating client God beliefs, AA attendance, patterns of AA attendance and alcohol use. Assessments were conducted at intake and in 3-month intervals using the Form 90, Religious Behaviors and Background, and the Alcoholics Anonymous Inventory. 12-Step treatment was significantly more likely to promote pre-post shifts in client God beliefs, and atheist and agnostic clients attended AA significantly less often throughout follow-up relative to clients self-labeled as spiritual and religious. AA attendance, however, was significantly associated with increased abstinence and reductions in drinking intensity regardless of God belief. Finally, no differences in percent days abstinence and drinking intensity were found between atheist and agnostic versus spiritual and religious clients, but clients unsure about their God belief reported significantly higher drinking frequency relative to the other groups. God belief appears to be relatively unimportant in deriving AA-related benefit, but atheist and agnostic clients are less likely to initiate and sustain AA attendance relative to spiritual and religious clients. This apparent reticence to affiliate with AA ought to be clinically recognized when encouraging AA participation.

  1. 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....

  2. 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....

  3. 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.

  4. Anonymous electronic trading versus floor trading

    OpenAIRE

    Franke, Günter; Hess, Dieter

    1995-01-01

    This paper compares the attractiveness of floor trading and anonymous electronic trading systems. It is argued that in times of low information intensity the insight into the order book of the electronic trading system provides more valuable information than floor trading, but in times of high information intensity the reverse is true. Thus, the electronic system's market share in trading activity should decline in times of high information intensity. This hypothesis is tested by data on BUND...

  5. 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.

  6. k-Times Anonymous Authentication

    Science.gov (United States)

    Teranishi, Isamu; Furukawa, Jun; Sako, Kazue

    We propose an authentication scheme in which users can be authenticated anonymously so long as times that they are authenticated is within an allowable number. The proposed scheme has two features: 1) no one, not even an authority, can identify users who have been authenticated within the allowable number, 2) anyone can trace, without help from the authority, dishonest users who have been authenticated beyond the allowable number by using the records of these authentications. Our scheme can be applied to e-voting, e-cash, electronic coupons, and trial browsing of content. In these applications, our scheme, unlike the previous one, conceals users' participation from protocols and guarantees that they will remain anonymous to everyone.

  7. 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....

  8. Anonymous Web Browsing and Hosting

    OpenAIRE

    MANOJ KUMAR; ANUJ RANI

    2013-01-01

    In today’s high tech environment every organization, individual computer users use internet for accessing web data. To maintain high confidentiality and security of the data secure web solutions are required. In this paper we described dedicated anonymous web browsing solutions which makes our browsing faster and secure. Web application which play important role for transferring our secret information including like email need more and more security concerns. This paper also describes that ho...

  9. Error Analysis of Ia Supernova and Query on Cosmic Dark Energy ...

    Indian Academy of Sciences (India)

    2007), we find that. 3.796% of the data is an outline of 2.6σ based on the average total observational error of the distance modulus of SNIa, 0.31 m . Obviously, the distance modulus error deviates Gaussian distribution seriously, and it is not suitable to calculate the system- atic error σsys of SNIa by the χ2 check test method.

  10. Comparative Analysis of Opioid Queries on Erowid.org: An Opportunity to Advance Harm Reduction.

    Science.gov (United States)

    Wightman, Rachel S; Perrone, Jeanmarie; Erowid, Fire; Erowid, Earth; Meisel, Zachary F; Nelson, Lewis S

    2017-08-24

    Many individuals who use opioids turn to online resources to gather information on effects, availability, and safety. Describe opioid index page views on Erowid.org to assess trends in public interest in particular opioids. Retrospective analysis of Erowid.org site traffic was performed to identify unique average daily visits to opioid pages. All data was normalized to that of visits to the heroin index page. Average daily visits to the index pages of each of 6 commonly abused opioids were assessed during the period of 2009 to 2015. Similarly, visits to 15 distinct opioid index pages at 5 time points (July, October 2014 and Jan, April, and July 2015) were described. From 2009 to 2015 a decrease in the number of page visits versus heroin (1.00) occurred for hydrocodone (0.87 to 0.59, -32%), oxycodone (1.38 to 0.99, -28%), and morphine (0.26 to 0.25, -6%). Increases in page visits compared to heroin occurred for fentanyl (0.18 to 0.47, +157%), tramadol (0.43 to 0.88, +106%), hydromorphone (0.19 to 0.24, +29%), and oxymorphone (0.11 to 0.13, +18%). Indexed to heroin (1.00) average opioid page visit frequencies from July 2014 to July 2015 were highest for oxycodone (1.02) and tramadol (0.81). Conclusion/Importance: Oxycodone and tramadol represent the greatest number of Erowid.org opioid page visits compared to heroin. The largest increase in visits over the study periods was for fentanyl and tramadol. The relationship of page visits on Erowid.org creates a unique opportunity for real-time evaluation of emerging drug trends and epidemiological study.

  11. Research on Web Search Behavior: How Online Query Data Inform Social Psychology.

    Science.gov (United States)

    Lai, Kaisheng; Lee, Yan Xin; Chen, Hao; Yu, Rongjun

    2017-10-01

    The widespread use of web searches in daily life has allowed researchers to study people's online social and psychological behavior. Using web search data has advantages in terms of data objectivity, ecological validity, temporal resolution, and unique application value. This review integrates existing studies on web search data that have explored topics including sexual behavior, suicidal behavior, mental health, social prejudice, social inequality, public responses to policies, and other psychosocial issues. These studies are categorized as descriptive, correlational, inferential, predictive, and policy evaluation research. The integration of theory-based hypothesis testing in future web search research will result in even stronger contributions to social psychology.

  12. High-precision positioning system of four-quadrant detector based on the database query

    Science.gov (United States)

    Zhang, Xin; Deng, Xiao-guo; Su, Xiu-qin; Zheng, Xiao-qiang

    2015-02-01

    The fine pointing mechanism of the Acquisition, Pointing and Tracking (APT) system in free space laser communication usually use four-quadrant detector (QD) to point and track the laser beam accurately. The positioning precision of QD is one of the key factors of the pointing accuracy to APT system. A positioning system is designed based on FPGA and DSP in this paper, which can realize the sampling of AD, the positioning algorithm and the control of the fast swing mirror. We analyze the positioning error of facular center calculated by universal algorithm when the facular energy obeys Gauss distribution from the working principle of QD. A database is built by calculation and simulation with MatLab software, in which the facular center calculated by universal algorithm is corresponded with the facular center of Gaussian beam, and the database is stored in two pieces of E2PROM as the external memory of DSP. The facular center of Gaussian beam is inquiry in the database on the basis of the facular center calculated by universal algorithm in DSP. The experiment results show that the positioning accuracy of the high-precision positioning system is much better than the positioning accuracy calculated by universal algorithm.

  13. In-Network Processing of an Iceberg Join Query in Wireless Sensor Networks Based on 2-Way Fragment Semijoins

    Science.gov (United States)

    Kang, Hyunchul

    2015-01-01

    We investigate the in-network processing of an iceberg join query in wireless sensor networks (WSNs). An iceberg join is a special type of join where only those joined tuples whose cardinality exceeds a certain threshold (called iceberg threshold) are qualified for the result. Processing such a join involves the value matching for the join predicate as well as the checking of the cardinality constraint for the iceberg threshold. In the previous scheme, the value matching is carried out as the main task for filtering non-joinable tuples while the iceberg threshold is treated as an additional constraint. We take an alternative approach, meeting the cardinality constraint first and matching values next. In this approach, with a logical fragmentation of the join operand relations on the aggregate counts of the joining attribute values, the optimal sequence of 2-way fragment semijoins is generated, where each fragment semijoin employs a Bloom filter as a synopsis of the joining attribute values. This sequence filters non-joinable tuples in an energy-efficient way in WSNs. Through implementation and a set of detailed experiments, we show that our alternative approach considerably outperforms the previous one. PMID:25774710

  14. In-Network Processing of an Iceberg Join Query in Wireless Sensor Networks Based on 2-Way Fragment Semijoins

    Directory of Open Access Journals (Sweden)

    Hyunchul Kang

    2015-03-01

    Full Text Available We investigate the in-network processing of an iceberg join query in wireless sensor networks (WSNs. An iceberg join is a special type of join where only those joined tuples whose cardinality exceeds a certain threshold (called iceberg threshold are qualified for the result. Processing such a join involves the value matching for the join predicate as well as the checking of the cardinality constraint for the iceberg threshold. In the previous scheme, the value matching is carried out as the main task for filtering non-joinable tuples while the iceberg threshold is treated as an additional constraint. We take an alternative approach, meeting the cardinality constraint first and matching values next. In this approach, with a logical fragmentation of the join operand relations on the aggregate counts of the joining attribute values, the optimal sequence of 2-way fragment semijoins is generated, where each fragment semijoin employs a Bloom filter as a synopsis of the joining attribute values. This sequence filters non-joinable tuples in an energy-efficient way in WSNs. Through implementation and a set of detailed experiments, we show that our alternative approach considerably outperforms the previous one.

  15. 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.

  16. 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 ...

  17. 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

  18. Our Anonymous Online Research Participants Are Not Always Anonymous: Is This a Problem?

    Science.gov (United States)

    Dawson, Phillip

    2014-01-01

    When educational research is conducted online, we sometimes promise our participants that they will be anonymous--but do we deliver on this promise? We have been warned since 1996 to be careful when using direct quotes in Internet research, as full-text web search engines make it easy to find chunks of text online. This paper details an empirical…

  19. 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...

  20. 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

  1. 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.

  2. Property-Based Anonymous Attestation in Trusted Cloud Computing

    Directory of Open Access Journals (Sweden)

    Zhen-Hu Ning

    2014-01-01

    Full Text Available In the remote attestation on Trusted Computer (TC computing mode TCCP, the trusted computer TC has an excessive burden, and anonymity and platform configuration information security of computing nodes cannot be guaranteed. To overcome these defects, based on the research on and analysis of current schemes, we propose an anonymous proof protocol based on property certificate. The platform configuration information is converted by the matrix algorithm into the property certificate, and the remote attestation is implemented by trusted ring signature scheme based on Strong RSA Assumption. By the trusted ring signature scheme based on property certificate, we achieve the anonymity of computing nodes and prevent the leakage of platform configuration information. By simulation, we obtain the computational efficiency of the scheme. We also expand the protocol and obtain the anonymous attestation based on ECC. By scenario comparison, we obtain the trusted ring signature scheme based on RSA, which has advantages with the growth of the ring numbers.

  3. A review on design of experiments and surrogate models in aircraft real-time and many-query aerodynamic analyses

    Science.gov (United States)

    Yondo, Raul; Andrés, Esther; Valero, Eusebio

    2018-01-01

    Full scale aerodynamic wind tunnel testing, numerical simulation of high dimensional (full-order) aerodynamic models or flight testing are some of the fundamental but complex steps in the various design phases of recent civil transport aircrafts. Current aircraft aerodynamic designs have increase in complexity (multidisciplinary, multi-objective or multi-fidelity) and need to address the challenges posed by the nonlinearity of the objective functions and constraints, uncertainty quantification in aerodynamic problems or the restrained computational budgets. With the aim to reduce the computational burden and generate low-cost but accurate models that mimic those full order models at different values of the design variables, Recent progresses have witnessed the introduction, in real-time and many-query analyses, of surrogate-based approaches as rapid and cheaper to simulate models. In this paper, a comprehensive and state-of-the art survey on common surrogate modeling techniques and surrogate-based optimization methods is given, with an emphasis on models selection and validation, dimensionality reduction, sensitivity analyses, constraints handling or infill and stopping criteria. Benefits, drawbacks and comparative discussions in applying those methods are described. Furthermore, the paper familiarizes the readers with surrogate models that have been successfully applied to the general field of fluid dynamics, but not yet in the aerospace industry. Additionally, the review revisits the most popular sampling strategies used in conducting physical and simulation-based experiments in aircraft aerodynamic design. Attractive or smart designs infrequently used in the field and discussions on advanced sampling methodologies are presented, to give a glance on the various efficient possibilities to a priori sample the parameter space. Closing remarks foster on future perspectives, challenges and shortcomings associated with the use of surrogate models by aircraft industrial

  4. Revocable Anonymous Access to the Internet?

    Science.gov (United States)

    Claessens, Joris; Diaz, Claudia; Goemans, Caroline; Preneel, Bart; Vandewalle, Joos; Dumortier, Jos

    2003-01-01

    Users of telecommunications networks are concerned about privacy, and desire anonymous access, while some organizations are concerned about how this anonymous access might be abused. Proposes a solution for revocable anonymous access to the Internet. Presents some legal background and motivation for such a solution. Indicates some difficulties and…

  5. College Students' Experiences with Anonymous Social Media: Implications for Campus Racial Climate

    Science.gov (United States)

    Armstrong, Amanda; Thomas, Jaymi; Smith, Madeline

    2017-01-01

    The purpose of this exploratory case study was to gather undergraduate students' perceptions of anonymous racist messages found on Yik Yak and to better understand the implications of anonymous platforms on campus racial climate. Given the limited research surrounding students' use of anonymous social media platforms, as well as the predominant…

  6. Traveling the Silk Road: A Measurement of a Large Anonymous Online Marketplace

    Science.gov (United States)

    2012-11-28

    Silk Road, an anonymous, international online marketplace that operates as a Tor hidden service and uses Bitcoin as its exchange currency. We gather...analysis of Silk Road, an anonymous, international on- line marketplace that operates as a Tor hidden service and uses Bitcoin as its exchange currency. We...anonymity, Silk Road needs to also preserve payment anonymity. To that effect, Silk Road only supports Bitcoin (BTC, [30]) as a trading currency

  7. Instant Cassandra query language

    CERN Document Server

    Singh, Amresh

    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. It's an Instant Starter guide.Instant Cassandra Query Language is great for those who are working with Cassandra databases and who want to either learn CQL to check data from the console or build serious applications using CQL. If you're looking for something that helps you get started with CQL in record time and you hate the idea of learning a new language syntax, then this book is for you.

  8. 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.

  9. Utility-preserving transaction data anonymization with low information loss.

    Science.gov (United States)

    Loukides, Grigorios; Gkoulalas-Divanis, Aris

    2012-08-01

    Transaction data record various information about individuals, including their purchases and diagnoses, and are increasingly published to support large-scale and low-cost studies in domains such as marketing and medicine. However, the dissemination of transaction data may lead to privacy breaches, as it allows an attacker to link an individual's record to their identity. Approaches that anonymize data by eliminating certain values in an individual's record or by replacing them with more general values have been proposed recently, but they often produce data of limited usefulness. This is because these approaches adopt value transformation strategies that do not guarantee data utility in intended applications and objective measures that may lead to excessive data distortion. In this paper, we propose a novel approach for anonymizing data in a way that satisfies data publishers' utility requirements and incurs low information loss. To achieve this, we introduce an accurate information loss measure and an effective anonymization algorithm that explores a large part of the problem space. An extensive experimental study, using click-stream and medical data, demonstrates that our approach permits many times more accurate query answering than the state-of-the-art methods, while it is comparable to them in terms of efficiency.

  10. 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...

  11. 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.

  12. 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...

  13. Montreal Accord on Patient-Reported Outcomes (PROs) use series - Paper 9: anonymization and ethics considerations for capturing and sharing patient reported outcomes.

    Science.gov (United States)

    Arbuckle, Luk; Moher, Ester; Bartlett, Susan J; Ahmed, Sara; El Emam, Khaled

    2017-09-01

    Patient-reported outcomes (PROs) are collected with consent for care; however, using the data for any other purpose requires consent for that additional purpose, or the anonymization of the data. Collecting explicit consent to use this data for secondary purposes, before the patient completes a PRO, can also bias the responses. We consider the ethical and security issues related to the collection of data at the point of care or in the population and the aggregation and integration of PRO data with administrative databases to facilitate decision making and comparative effectiveness research. In this article, we describe risk-based anonymization, taking the context of the data release into account, so that we may consider the degree by which the release is considered anonymized. We also consider the ethical use of anonymized data, the anonymization of free-form text, and the secure linking data sets without sharing any personal information. Many good standards and best practices exist for the sharing of health data and could be used as a baseline in the development of a national PRO initiative. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. LPPS: A Distributed Cache Pushing Based K-Anonymity Location Privacy Preserving Scheme

    Directory of Open Access Journals (Sweden)

    Ming Chen

    2016-01-01

    Full Text Available Recent years have witnessed the rapid growth of location-based services (LBSs for mobile social network applications. To enable location-based services, mobile users are required to report their location information to the LBS servers and receive answers of location-based queries. Location privacy leak happens when such servers are compromised, which has been a primary concern for information security. To address this issue, we propose the Location Privacy Preservation Scheme (LPPS based on distributed cache pushing. Unlike existing solutions, LPPS deploys distributed cache proxies to cover users mostly visited locations and proactively push cache content to mobile users, which can reduce the risk of leaking users’ location information. The proposed LPPS includes three major process. First, we propose an algorithm to find the optimal deployment of proxies to cover popular locations. Second, we present cache strategies for location-based queries based on the Markov chain model and propose update and replacement strategies for cache content maintenance. Third, we introduce a privacy protection scheme which is proved to achieve k-anonymity guarantee for location-based services. Extensive experiments illustrate that the proposed LPPS achieves decent service coverage ratio and cache hit ratio with lower communication overhead compared to existing solutions.

  15. Electronic voting systems for defending free will and resisting bribery and coercion based on ring anonymous signcryption scheme

    Directory of Open Access Journals (Sweden)

    Tsung-Chih Hsiao

    2017-01-01

    Full Text Available Vote by ballot is the feature in a democratic society and the process of decision-making, tending to achieve the philosophy of democratic politics by having the public who are eligible to vote for competent candidates or leaders. With the rapid development of technologies and network applications, electronization has been actively promoted globally during the social transformation period that the concept of electronic voting is further derived. The major advantages of electronic voting, comparing with traditional voting, lie in the mobility strength of electronic voting, reducing a large amount of election costs and enhancing the convenience for the public. Electronic voting allows voters completing voting on the Internet that not only are climate and location restrictions overcome, but the voter turnout is also increased and the voting time is reduced for the public. With the development in the past three decades, electronic voting presents outstanding performance theoretically and practically. Nevertheless, it is regrettable that electronic voting schemes still cannot be completely open because of lures by money and threats. People to lure by money and threats would confirm the voters following their instructions through various methods that more factors would appear on election results, affecting the quality and fairness of the election. In this study, this project aims to design an electronic voting scheme which could actually defend voters’ free will so that lure of money and threats would fail. Furthermore, an electronic voting system based on Elliptic Curve Cryptography is proposed to ensure the efficiency and security, and Ring Signature and Signcryption are applied to reducing the computing costs. Moreover, this project also focuses on applying voting system to mobile devices. As the system efficiency and security are emphasized, voters do not need to participate in the election, but simply complete voting with smart phones, i

  16. Authentic Attributes with Fine-Grained Anonymity Protection

    Science.gov (United States)

    2000-01-01

    registrations and ecommerce trans- Preprint - 2 Stuart G. Stubblebine, and Paul F. Syverson. Authentic Attributes with Fine-Grained Anonymity Protection...driver’s license and birth certi cate. When the registration process is complete, certi cates could be on a smart card that the customer is carrying. The...proof. At least initially, it might not be electronic, e.g., possession of a passport, of a driver’s license and birth certi cate, etc. Anonymous

  17. Alcoholics Anonymous and nursing. Lessons in holism and spiritual care.

    Science.gov (United States)

    McGee, E M

    2000-03-01

    Alcoholic Anonymous (AA) is a worldwide, million-member organization that has assisted countless alcoholics to achieve sobriety through a spiritual program of recovery from alcoholism. Based on spiritual principles known as the "Twelve Steps" and "Twelve Traditions," AA has provided a model for other recovery programs such as Narcotics Anonymous (NA), Gamblers Anonymous (GA), and Sex and Love Addicts Anonymous (SLAA). Recovery in AA appears to involve a process of self-transcendence. In recent years, nursing scholars have increasingly explored the concepts of self-transcendence and spirituality as they apply to nursing theory and practice. This article explores the roots and spiritual dimensions of 12-step recovery programs. It further explores the ways in which theoretical and clinical knowledge about the delivery of spiritual care interventions may be gained from an understanding of AA's spiritual approach to recovery.

  18. 基于HTML5+jQuery Mobile的移动Web应用开发研究%Study of mobile web application development based on HTML5 and jQuery Mobile

    Institute of Scientific and Technical Information of China (English)

    覃凤萍

    2015-01-01

    With the rapidly growing popularity of smart devices such as iphone and Android,mobile web technology has gradually become a new hot spot of concern,traditional site will be transferred to the mobile terminal due to market demand . Using jQuery Mobile and HTML5 to do mobile web application development, with the development of simple, short release cycle, cross-platform, cross-platform advantages . In this paper, jQuery Mobile and HTML5 mobile web application development made a presentation and analysis.%随着iphone、Android等智能设备的迅速普及,移动Web技术逐渐成为关注的新热点,传统信息类和电子商务网站因市场需求向移动终端转移。使用jQuery Mobile和HTML5做移动Web应用开发,具有开发简单,发布周期短、跨平台跨设备的优点。文章对jQuery Mobile和HTML5的移动Web应用开发做了介绍和分析。

  19. Static dictionaries on AC0 RAMs: query time (√log n/log log n) is necessary and sufficient

    DEFF Research Database (Denmark)

    Andersson, Arne; Miltersen, Peter Bro; Riis, Søren

    1996-01-01

    ) on the time for answering membership queries in a set of size n when reasonable space is used for the data structure storing the set; the upper bound can be obtained using O(n) space, and the lower bound holds even if we allow space 2polylog n. Several variations of this result are also obtained. Among others......, we show a tradeoff between time and circuit depth under the unit-cost assumption: any RAM instruction set which permits a linear space, constant query time solution to the static dictionary problem must have an instruction of depth Ω(log w/log log to), where w is the word size of the machine (and log...

  20. From Questions to Queries

    Directory of Open Access Journals (Sweden)

    M. Drlík

    2007-12-01

    Full Text Available The extension of (Internet databases forceseveryone to become more familiar with techniques of datastorage and retrieval because users’ success often dependson their ability to pose right questions and to be able tointerpret their answers. University programs pay moreattention to developing database programming skills than todata exploitation skills. To educate our students to become“database users”, the authors intensively exploit supportivetools simplifying the production of database elements astables, queries, forms, reports, web pages, and macros.Videosequences demonstrating “standard operations” forcompleting them have been prepared to enhance out-ofclassroomlearning. The use of SQL and other professionaltools is reduced to the cases when the wizards are unable togenerate the intended construct.

  1. Suicidal behavior among members of Gamblers Anonymous.

    Science.gov (United States)

    Frank, M L; Lester, D; Wexler, A

    1991-09-01

    A national sample of 500 members of Gamblers Anonymous was surveyed by mail in order to gather information on suicidal history. One hundred sixty two usable surveys were returned representing 32.4% of the original sample. Compulsive gamblers who had a history of suicidal preoccupation began gambling at an earlier age than nonsuicidal gamblers and were more likely to have stolen to support their gambling. They also tended to have addicted relatives and children more than nonsuicidal gamblers did. The data suggest that those gamblers who had been suicidal tend to be more serious gamblers than nonsuicidal respondents.

  2. Towards Predicting Efficient and Anonymous Tor Circuits

    OpenAIRE

    Barton, Armon; Imani, Mohsen; Ming, Jiang; Wright, Matthew

    2018-01-01

    The Tor anonymity system provides online privacy for millions of users, but it is slower than typical web browsing. To improve Tor performance, we propose PredicTor, a path selection technique that uses a Random Forest classifier trained on recent measurements of Tor to predict the performance of a proposed path. If the path is predicted to be fast, then the client builds a circuit using those relays. We implemented PredicTor in the Tor source code and show through live Tor experiments and Sh...

  3. Perspectives on the Massachusetts Community Health Information Profile (MassCHIP): developing an online data query system to target a variety of user needs and capabilities.

    Science.gov (United States)

    Cohen, Bruce B; Franklin, Saul; West, James K

    2006-01-01

    The Massachusetts Community Health Information Profile (MassCHIP) has many distinctive features. These features evolved to maximize the usefulness of this query system for a broad group of users with varied needs, differing levels of knowledge about public health, and diverse experience using public health data. Three major features of MassCHIP help target our large user population. These features are as follows: (1) multiple avenues of entry to initiate queries ranging from an alphabetical list of simple topics to detailed International Classification of Disease codes; (2) the inclusion of data sets from other state agencies in addition to those of the Massachusetts Department of Public Health to reflect a broad view of public health; and (3) the capacity to retrieve data for multiple levels of geography, from the neighborhood through the state, including planning districts and hospitals. In this article, we discuss the history and design of MassCHIP, and focus on the features of MassCHIP that target a great variety of user needs and capabilities, and which are distinctive among Web-based data query systems.

  4. 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.

  5. 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

  6. For the Lulz: Anonymous, Aesthetics and Affect

    Directory of Open Access Journals (Sweden)

    Rodrigo Ferrada Stoehrel

    2014-03-01

    Full Text Available The focus of this paper is on different but connected areas of power – relating to things such as economic globalisation, surveillance, censorship/freedom, ‘terrorism’ and/or specific military activity – visually represented through online media, and intentionally produced to inform a wide spectrum of individuals and interest groups about global and local social injustices. Or, more importantly, produced and distributed with the purpose of providing users with possibilities to engage, bodily and emotionally, in diverse ways: may it be through physical antiwar/anti-wall street protests or hacktivist tactics (e.g. DDoS attacks. We examine a sample of videos, photographs and propaganda posters produced, and digitally distributed (2008-2013, by the fragmented body of activists united globally under the generic name of Anonymous. Analytically, we will draw upon Mouffe’s thoughts on ‘antagonism’ and ‘passion,’ Foucault’s ideas on international citizenship and the (ethical ‘right to intervene’ (beyond governmentality, together with Sontag’s notion of institutional political inertia and the Deleuzian/Spinozian perspective on affect as a capacity for action. The goal is to analyse the ways in which Anonymous systematically inspire (not only the radical and social imaginary but also other direct forms of action that have potential societal effects.

  7. Factors associated with shooting accuracy and wounding rate of four managed wild deer species in the UK, based on anonymous field records from deer stalkers.

    Directory of Open Access Journals (Sweden)

    Nicholas J Aebischer

    Full Text Available The amount of wounding during routine culling is an important factor in the welfare of wild deer. Little information exists on factors determining shooting accuracy and wounding rates under field conditions in the UK. In this study, 102 anonymous stalkers collected data on the outcomes and circumstances of 2281 shots. Using hot-deck imputation and generalised linear mixed modelling, we related the probability that a shot hit its target, and the probability that the shot killed the deer if it was hit, to 28 variables describing the circumstances of the shot. Overall, 96% of deer were hit, of which 93% were killed outright. A reduced probability of hitting the target was associated with an uncomfortable firing position, too little time available, shooting off elbows or freehand, taking the head or upper neck as point of aim, a heavily obscured target, a distant target, shooting at females, lack of shooting practice and a basic (or no stalker qualification. An increase in the likelihood of wounding was associated with an uncomfortable firing position, shooting with insufficient time, a distant target (only when time was not sufficient, a bullet weight below 75 grains, a target concealed in thicket or on the move and an area rarely stalked. To maximise stalking success and deer welfare, we recommend that stalkers ensure a comfortable firing position, use a gun rest, aim at the chest, use bullets heavier than 75 grains, avoid taking a rushed shot, shoot a distant animal only if there is plenty of time, fire only when the target is stationary, avoid shooting at an obscured animal, take care when the ground is unfamiliar, and do shooting practice at least once a month. The high miss rate of basic-level stalkers suggests that training should include additional firing practice under realistic shooting conditions.

  8. 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.

  9. 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.

  10. Browsing the Internet: good-bye anonymity!

    CERN Multimedia

    Computer Security Team

    2012-01-01

    Do you consider browsing the Internet to be your private business? When visiting random web-sites, how far do you assume you are anonymous? Would it matter to you that Google or Facebook can profile your browsing behaviour in order to better target you with advertisements? Did you notice that you already get targeted ads when you are logged on to Google or Facebook even if you are visiting completely different websites? If matters to you, note that browsing anonymously on the Internet is far from easy.   When you are connected to the Internet, you give away a variety of information: your PC’s IP address, some browser settings like language or screen size, and, probably, your login information. So how private is private? You might argue that your current IP address has been picked from a pool of addresses and therefore regularly changes, so it does not necessarily always pinpoint you. On the other hand, with the dawn of IPv6 there is no need any more for shared IP addresses as the...

  11. 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

  12. Practical anonymity hiding in plain sight online

    CERN Document Server

    Loshin, Peter

    2013-01-01

    For those with legitimate reason to use the Internet anonymously--diplomats, military and other government agencies, journalists, political activists, IT professionals, law enforcement personnel, political refugees and others--anonymous networking provides an invaluable tool, and many good reasons that anonymity can serve a very important purpose. Anonymous use of the Internet is made difficult by the many websites that know everything about us, by the cookies and ad networks, IP-logging ISPs, even nosy officials may get involved. It is no longer possible to turn off browser cookies to be l

  13. Comparison of the Personality Profiles of Inmate Anonymous and Non-Anonymous Male Addicts

    Directory of Open Access Journals (Sweden)

    Nasrolah Erfani

    2013-05-01

    Full Text Available Aim: This study compared the personality profiles of inmate anonymous and non-anonymous male addicts. Method: The participants of study were anonymous and non-anonymous male addicts of the prisons of the Hamadan province in 1391. The population was 3130 addicts, including 627 anonymous and 2503 non-anonymous addicts. The 310 addicts were selected by stratified random sampling the sample size was determined by Cochran formula.The short-form NEO Five Factor personality questionnaire administered among selected sample. Data analyzed by descriptive statistic as frequency and percentage, also, inferential statistic as multivariate analysis of variance was run. Results: The results showed that personality profiles of anonymous and non-anonymous addicts were significantly different. That is, mean score of neuroticism in anonymous addicts was less than non anonymous. Also, mean score of extraversion was higher in anonymous addicts. Conclusion: It can be concluded that the anonymous male addicts are differ with non-anonymous male addicts in personality traits.

  14. 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...

  15. 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

  16. 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.

  17. Instant jQuery selectors

    CERN Document Server

    De Rosa, Aurelio

    2013-01-01

    Filled with practical, step-by-step instructions and clear explanations for the most important and useful tasks. Instant jQuery Selectors follows a simple how-to format with recipes aimed at making you well versed with the wide range of selectors that jQuery has to offer through a myriad of examples.Instant jQuery Selectors is for web developers who want to delve into jQuery from its very starting point: selectors. Even if you're already familiar with the framework and its selectors, you could find several tips and tricks that you aren't aware of, especially about performance and how jQuery ac

  18. 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

  19. 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...

  20. Evaluation of Sub Query Performance in SQL Server

    Science.gov (United States)

    Oktavia, Tanty; Sujarwo, Surya

    2014-03-01

    The paper explores several sub query methods used in a query and their impact on the query performance. The study uses experimental approach to evaluate the performance of each sub query methods combined with indexing strategy. The sub query methods consist of in, exists, relational operator and relational operator combined with top operator. The experimental shows that using relational operator combined with indexing strategy in sub query has greater performance compared with using same method without indexing strategy and also other methods. In summary, for application that emphasized on the performance of retrieving data from database, it better to use relational operator combined with indexing strategy. This study is done on Microsoft SQL Server 2012.

  1. Is it OK to be an Anonymous?

    NARCIS (Netherlands)

    Serracino Inglott, P.

    2013-01-01

    Do the deviant acts carried out by the collective known as Anonymous qualify as vigilante activity, and if so, can they be justified? Addressing this question helps expose the difficulties of morally evaluating technologically enabled deviance. Anonymous is a complex, fluid actor but not as

  2. 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.

  3. 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.

  4. 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.

  5. Criminal offenses in gamblers anonymous and hospital treated pathological gamblers.

    Science.gov (United States)

    Blaszczynski, A P; McConaghy, N

    1994-06-01

    The purpose of this study was to compare the nature and prevalence of gambling and non-gambling related offenses in samples of pathological gamblers seeking behavioural treatment from a hospital-based program and those attending Gamblers Anonymous. A semi-structured interview schedule obtaining demographic data and details of the nature, frequency, and consequent legal action of criminal offenses committed was administered to 152 consecutive hospital treated pathological gamblers, and 154 Gamblers Anonymous attendees who volunteered to participate in the study. Of the total sample, 59% admitted a gambling-related offense, and 23% to a conviction. There was no difference in the proportion of hospital treated and Gamblers Anonymous subjects who offended. The most common gambling-related offenses were larceny, embezzlement and misappropriation. Gamblers committed a median of ten offenses over an average ten year period of pathological gambling with a median value of $ A 300(1) per offense. The median value for each non-gambling-related offense was $ A 130. Except for the significantly older mean age of Gamblers Anonymous subjects, hospital treated gamblers did not differ from Gamblers Anonymous attenders on relevant demographic features or parameters of gambling behaviour. Findings were interpreted to suggest a possible causal link between pathological gambling and the commission of non-violent property offenses.

  6. Anonymity in Peer-assisted CDNs: Inference Attacks and Mitigation

    Directory of Open Access Journals (Sweden)

    Jia Yaoqi

    2016-10-01

    Full Text Available The peer-assisted CDN is a new content distribution paradigm supported by CDNs (e.g., Akamai, which enables clients to cache and distribute web content on behalf of a website. Peer-assisted CDNs bring significant bandwidth savings to website operators and reduce network latency for users. In this work, we show that the current designs of peer-assisted CDNs expose clients to privacy-invasive attacks, enabling one client to infer the set of browsed resources of another client. To alleviate this, we propose an anonymous peer-assisted CDN (APAC, which employs content delivery while providing initiator anonymity (i.e., hiding who sends the resource request and responder anonymity (i.e., hiding who responds to the request for peers. APAC can be a web service, compatible with current browsers and requiring no client-side changes. Our anonymity analysis shows that our APAC design can preserve a higher level of anonymity than state-of-the-art peer-assisted CDNs. In addition, our evaluation demonstrates that APAC can achieve desired performance gains.

  7. 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...

  8. 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.

  9. 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...

  10. 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

  11. 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...

  12. Anonymous Authorship Control for User-Generated Content

    Directory of Open Access Journals (Sweden)

    Suk-Bong LEE

    2007-12-01

    Full Text Available User-Generated Content (UGC is opening up new large market in content services, and more and more people are visiting web sites to share and enjoy UGCs. These trends make many authors to move into online. Authors want to conserve their authorship and expect to publish their UGC anonymously in cases. To meet the requirements, we propose a new authorship control model based on watermarking and metadata. Authors can embed their authorship into their UGC with identities or with anonym. Even though an author publishes his UGC anonymously, he can prove his authorship without unveiling his identity via 5 methods utilizing the proposed authorship model. The proposed model and methods need no TTP and are robust even based on fragile underlying watermarking scheme.

  13. Structure and Anonymity of the Bitcoin Transaction Graph

    Directory of Open Access Journals (Sweden)

    Kay Hamacher

    2013-05-01

    Full Text Available The Bitcoin network of decentralized payment transactions has attracted a lot of attention from both Internet users and researchers in recent years. Bitcoin utilizes a peer-to-peer network to issue anonymous payment transactions between different users. In the currently used Bitcoin clients, the full transaction history is available at each node of the network to prevent double spending without the need for a central authority, forming a valuable source for empirical research on network structure, network dynamics, and the implied anonymity challenges, as well as guidance on the future evolution of complex payment systems. We found dynamical effects of which some increase anonymity while others decrease it. Most importantly, several parameters of the Bitcoin transaction graph seem to have become stationary over the last 12–18 months. We discuss the implications.

  14. 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.

  15. Achieving sink node anonymity in tactical wireless sensor networks using a reactive routing protocol

    Science.gov (United States)

    2017-06-01

    node anonymity, base station anonymity, Wireless Sensor Networks (WSN), Mobile Ad hoc Network (MANET), Lightweight Ad hoc On-Demand – Next Generation ... Generation (LOADng) reactive-routing protocol to achieve anonymity. This modified protocol prevents an attacker from identifying the sink node without...within the constraints of WSN communication protocols, specifically IEEE 802.15.4. We use and modify the Lightweight Ad hoc On-Demand – Next Generation

  16. XAL: An algebra for XML query optimization

    NARCIS (Netherlands)

    Frasincar, F.; Houben, G.J.P.M.; Pau, C.D.; Zhou, Xiaofang

    2002-01-01

    This paper proposes XAL, an XML ALgebra. Its novelty is based on the simplicity of its data model and its well-defined logical operators, which makes it suitable for composability, optimizability, and semantics definition of a query language for XML data. At the heart of the algebra resides the

  17. Web-Based Distributed XML Query Processing

    NARCIS (Netherlands)

    Smiljanic, M.; Feng, L.; Jonker, Willem; Blanken, Henk; Grabs, T.; Schek, H-J.; Schenkel, R.; Weikum, G.

    2003-01-01

    Web-based distributed XML query processing has gained in importance in recent years due to the widespread popularity of XML on the Web. Unlike centralized and tightly coupled distributed systems, Web-based distributed database systems are highly unpredictable and uncontrollable, with a rather

  18. 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

  19. 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.

  20. 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.

  1. 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.

  2. Authority and Hierarchy within Anonymous Internet Relay Chat Networks

    Directory of Open Access Journals (Sweden)

    Stewart Kenton Bertram

    2015-09-01

    Full Text Available 'The protest group Anonymous has emerged as one of the most significant social movements of recent years, announcing their arrival as a globally recognized brand with regular disruptive cyber attacks and the leak of large volumes of sensitive data. Despite the obvious significance of Anonymous, to date, little academic research has been focused on what role hierarchy and internal authority play (if any within the group. Bespoke software was used to structure over 5000 examples of IRC log files, so that a base line descriptive statistical picture could be drawn, as well as a more granular enumeration of the privileges associated with individual users.'

  3. Anonymity in P2P Systems

    Science.gov (United States)

    Manzanares-Lopez, Pilar; Muñoz-Gea, Juan Pedro; Malgosa-Sanahuja, Josemaria; Sanchez-Aarnoutse, Juan Carlos

    In the last years, the use of peer-to-peer (P2P) applications to share and exchange knowledge among people around the world has experienced an exponential growth. Therefore, it is understandable that, like in any successful communication mechanism used by a lot of humans being, the anonymity can be a desirable characteristic in this scenario. Anonymity in P2P networks can be obtained by means of different methods, although the most significant ones are broadcast protocols, dining-cryptographer (DC) nets and multiple-hop paths. Each of these methods can be tunable in order to build a real anonymity P2P application. In addition, there is a mathematical tool called entropy that can be used in some scenarios to quantify anonymity in communication networks. In some cases, it can be calculated analytically but in others it is necessary to use simulation to obtain the network entropy.

  4. 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;…

  5. Real SQL queries 50 challenges : practice for reporting and analysis

    CERN Document Server

    Cohen, Brian; Mishra, Neerja

    2015-01-01

    Queries improve when challenges are authentic. This book sets your learning on the fast track with realistic problems to solve. Topics span sales, marketing, human resources, purchasing, and production. Real SQL Queries: 50 Challenges is perfect for analysts, report writers, or anyone searching for a hands-on approach to learning SQL Server.

  6. Anonymous Agencies, Backstreet Businesses and Covert Collectives

    DEFF Research Database (Denmark)

    Krause Hansen, Hans; Schoeneborn, Dennis

    2015-01-01

    Book review of: Anonymous Agencies, Backstreet Businesses and Covert Collectives: rethinking Organizations in the 21st Century, C. R. Scott. Stanford, CA: Stanford University Press, 2013. 272 pp. £45.90. ISBN 9780804781381......Book review of: Anonymous Agencies, Backstreet Businesses and Covert Collectives: rethinking Organizations in the 21st Century, C. R. Scott. Stanford, CA: Stanford University Press, 2013. 272 pp. £45.90. ISBN 9780804781381...

  7. 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

  8. Protecting genomic sequence anonymity with generalization lattices.

    Science.gov (United States)

    Malin, B A

    2005-01-01

    Current genomic privacy technologies assume the identity of genomic sequence data is protected if personal information, such as demographics, are obscured, removed, or encrypted. While demographic features can directly compromise an individual's identity, recent research demonstrates such protections are insufficient because sequence data itself is susceptible to re-identification. To counteract this problem, we introduce an algorithm for anonymizing a collection of person-specific DNA sequences. The technique is termed DNA lattice anonymization (DNALA), and is based upon the formal privacy protection schema of k -anonymity. Under this model, it is impossible to observe or learn features that distinguish one genetic sequence from k-1 other entries in a collection. To maximize information retained in protected sequences, we incorporate a concept generalization lattice to learn the distance between two residues in a single nucleotide region. The lattice provides the most similar generalized concept for two residues (e.g. adenine and guanine are both purines). The method is tested and evaluated with several publicly available human population datasets ranging in size from 30 to 400 sequences. Our findings imply the anonymization schema is feasible for the protection of sequences privacy. The DNALA method is the first computational disclosure control technique for general DNA sequences. Given the computational nature of the method, guarantees of anonymity can be formally proven. There is room for improvement and validation, though this research provides the groundwork from which future researchers can construct genomics anonymization schemas tailored to specific datasharing scenarios.

  9. Der Einfluss von Anonymität in der Lehrevaluation durch Studierende [The Effects of Anonymity on Student Ratings of Teaching and Course Quality in a Bachelor Degree Programme

    Directory of Open Access Journals (Sweden)

    Schaffner, Noemi

    2013-08-01

    Full Text Available [english] Research Question: Are there any clear differences between the outcomes of anonymous and personalised student evaluations of teaching quality?Methods: During a two-year period students were randomly divided into two separate groups, “anonymous” and “personalised”, for end-of-module evaluations. The quality of the module was assessed using a standardised questionnaire. Additionally, students were given the option to add “further comments” if they wanted to highlight specifics.These optional comments were independently assessed by three people, using a five-dimensional rating instrument: positive/negative; differentiated/absolute; naming a person/general; containing an order/neutral; visually accentuated/blank.The database consisted of 615 evaluation forms, of which 306 were completed anonymously. In order to identify whether there were any differences between the anonymous and personalised data, a multivariate variance analysis was performed. Based on the scale, the answers to the questions and the quality of the comments were evaluated. Furthermore, an assessment was made to determine if there were any differences in the number of optional comments between the two groups. Results: No significant differences were identified in the informative quality of data between the anonymous and personalised student evaluations. However, students in the personalised group had a tendency to include more details in their written answers.Conclusion: Personalised evaluations do not generate more biased results in terms of social desirability, as long as the evaluation concept is characterised by a closed-circle process and is transparent. In other words, it is imperative that the outcomes of the evaluation are reported back to the students. Moreover, there has to be an opportunity for students to discuss any further suggestions and/or future desires in an open environment. In this way the students respect and understand that their feedback

  10. 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....

  11. 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,

  12. 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

  13. An Experimental Investigation of Complexity in Database Query Formulation Tasks

    Science.gov (United States)

    Casterella, Gretchen Irwin; Vijayasarathy, Leo

    2013-01-01

    Information Technology professionals and other knowledge workers rely on their ability to extract data from organizational databases to respond to business questions and support decision making. Structured query language (SQL) is the standard programming language for querying data in relational databases, and SQL skills are in high demand and are…

  14. 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

  15. 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…

  16. 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

  17. 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

  18. 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.

  19. Simplifying Itai-Rodeh leaderelection for anonymous rings

    NARCIS (Netherlands)

    W.J. Fokkink (Wan); J. Pang

    2004-01-01

    textabstractWe present two probabilistic leader election algorithms for anonymous unidirectional rings with FIFO channels, based on an algorithm from Itai and Rodeh. In contrast to the Itai-Rodeh algorithm, our algorithms are finite-state. So they can be analyzed using explicit state space

  20. Simplifying Itai-Rodeh Leader Election for Anonymous Rings

    NARCIS (Netherlands)

    Fokkink, W.J.; Pang, J.

    2005-01-01

    We present two probabilistic leader election algorithms for anonymous unidirectional rings with FIFO channels, based on an algorithm from Itai and Rodeh [A. Itai and M. Rodeh. Symmetry breaking in distributive networks. In Proc. FOCS'81, pp. 150-158. IEEE Computer Society, 1981]. In contrast to the

  1. Anonymous pastoral care for problems pertaining to sexuality

    NARCIS (Netherlands)

    van Drie, A.; Ganzevoort, R.R.; Spiering, M.

    2014-01-01

    Anonymous pastoral care is one of the options for help in problems pertaining to sexuality. This paper explores the topics they seek help for, the religious aspects involved, and the relation between the normativity of their church tradition on the one hand and sexual and spiritual health criteria

  2. 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.

  3. 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...

  4. 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%.

  5. 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%.

  6. 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....

  7. 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.

  8. Social distance and anonymity modulate fairness consideration: An ERP study

    Science.gov (United States)

    Yu, Rongjun; Hu, Pan; Zhang, Ping

    2015-01-01

    Previous research indicated that fairness consideration can be influenced by social distance. However, it is not clear whether social distance and anonymity have an interactive impact on fairness evaluation during asset distribution and whether these processes can be documented in brain activity. Using a modified ultimatum game combined with measures of event related potential (ERP), we examined how social distance and anonymity modulate brain response to inequality. At the behavior level, we found that acceptance rate and reaction time can be substantially modified by social distance and anonymity. Feedback-related negativity, an ERP component associated with conflict between cognitive and emotion motives, was more negative in response to unfairness than fairness from strangers; however, it showed an opposite trend for unfair offers provided by friends, suggesting that the influence of social distance on fairness perception is relatively fast. The P300 in response to fair offers was more positive when the proposers made offers when uncertain about partner identity than when certain about partner identity. These results suggest that unfairness is evaluated in a fast conflict detection stage and a slower stage that integrates more complex social contextual factors such as anonymity. PMID:26293456

  9. 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.

  10. 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

  11. Probabilistic Structured Query Methods

    National Research Council Canada - National Science Library

    Darwish, Kareem; Oard, Douglas W

    2003-01-01

    .... Statistically significant improvements in retrieval effectiveness are demonstrated for cross-language retrieval and for retrieval based on optical character recognition when replacement probabilities...

  12. 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

  13. 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.

  14. Querying Large Biological Network Datasets

    Science.gov (United States)

    Gulsoy, Gunhan

    2013-01-01

    New experimental methods has resulted in increasing amount of genetic interaction data to be generated every day. Biological networks are used to store genetic interaction data gathered. Increasing amount of data available requires fast large scale analysis methods. Therefore, we address the problem of querying large biological network datasets.…

  15. Same query - different results

    International Nuclear Information System (INIS)

    Nevyjel, A.

    1983-10-01

    On behalf of a case study a simple truncated adjacency phrase search was executed in the online versions of Chemical Abstracts on five different host computers (DATA-STAR, DIALOG, ESA, SDC, TELESYSTEMES). The reasons for the differences in the appearing results are discussed. (Author) [de

  16. Is it OK to be an Anonymous?

    Directory of Open Access Journals (Sweden)

    Philip Serracino-Inglott

    2013-12-01

    Full Text Available Do the deviant acts carried out by the collective known as Anonymous qualify as vigilante activity, and if so, can they be justified? Addressing this question helps expose the difficulties of morally evaluating technologically enabled deviance. Anonymous is a complex, fluid actor but not as mysterious as popularly portrayed. Under a definition of vigilantism that includes reprobative punishment rather than violence as a key element, Anonymous are vigilantes. Many of its Ops can be justified in view of the mismatch between formal norm enforcement practice and Internet natives’ experience of it. Anons are more like eco-warriors than terrorists. While their actions are contentious, their force is framed in a vision of common good that is not unreasonable. Engaging with online deviants is shown to be a productive way of identifying the weaknesses in concepts underpinning moral evaluation of Internet-enabled phenomena.

  17. Predictors of anonymous cyber aggression: the role of adolescents' beliefs about anonymity, aggression, and the permanency of digital content.

    Science.gov (United States)

    Wright, Michelle F

    2014-07-01

    Little attention has been given to whether adolescents' beliefs about anonymity and their normative beliefs about cyber aggression jointly increase their perpetration of cyber aggression. To this end, the present longitudinal study examined the moderating influence of these variables on the relationships among adolescents' attitudes toward the permanency of digital content, confidence with not getting caught, and anonymous cyber aggression (ACA) assessed 1 year later (Time 2). These associations were examined among 274 7th and 8th graders and through five technologies, including social networking sites (SNS), e-mail, instant messenger (IM), mobile phones, and chatrooms. Findings indicated that increases in Time 2 ACA and attitudes toward the permanency of digital content were more strongly related when adolescents reported greater confidence with not getting caught and higher normative beliefs concerning cyber aggression through SNS and mobile phones. In addition, higher levels of attitudes toward the permanency of digital content, confidence with not getting caught, beliefs about anonymity, and normative beliefs regarding cyber aggression were related to greater Time 2 ACA through e-mail, IM, and chatrooms. All findings are discussed in the context of adolescents' positive attitudes toward ACA, and an appeal for additional research is made to understand more about anonymity in cyberspace.

  18. Anonymous Communication Policies for the Internet: Results and Recommendations of the AAAS Conference.

    Science.gov (United States)

    Teich, Al; Frankel, Mark S.; Kling, Rob; Lee, Yaching

    1999-01-01

    Reports the results of a conference on the Internet and anonymous communication organized by the American Association for the Advancement of Science (AAAS). Discusses how anonymous communications can be shaped by the law, education, and public awareness, and highlights the importance of involving all affected interests in policy development.…

  19. The Risk of a Halo Bias as a Reason to Keep Students Anonymous during Grading

    Science.gov (United States)

    Malouff, John M.; Emmerton, Ashley J.; Schutte, Nicola S.

    2013-01-01

    Experts have advocated anonymous grading as a means of eliminating actual or perceived evaluator bias in subjective student assessment. The utility of anonymity in assessment rests on whether information derived from student identity can unduly influence evaluation. The halo effect provides a conceptual background for why a bias might occur. In…

  20. TEMPORAL QUERY PROCESSIG USING SQL SERVER

    OpenAIRE

    Vali Shaik, Mastan; Sujatha, P

    2017-01-01

    Most data sources in real-life are not static but change their information in time. This evolution of data in time can give valuable insights to business analysts. Temporal data refers to data, where changes over time or temporal aspects play a central role. Temporal data denotes the evaluation of object characteristics over time. One of the main unresolved problems that arise during the data mining process is treating data that contains temporal information. Temporal queries on time evolving...

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

    KAUST Repository

    Xie, Qing; Zhang, Xiangliang; Li, Zhixu; Zhou, Xiaofang

    2016-01-01

    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

  2. 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....

  3. A Framework For Enhancing Privacy In Location Based Services Using K-Anonymity Model

    Directory of Open Access Journals (Sweden)

    Jane Mugi

    2015-08-01

    Full Text Available Abstract This paper presents a framework for enhancing privacy in Location Based Services using K-anonymity model. Users of location based services have to reveal their location information in order to use these services however this has threatened the user privacy. K-anonymity approach has been studied extensively in various forms. However it is only effective when the user location is fixed. When a user moves and continuously sends their location information the location service provider can approximate user trajectory which poses a threat to the trajectory privacy of the user. This framework will ensure that user privacy is enhanced for both snapshot and continuous queries. The efficiency and effectiveness of the proposed framework was evaluated the results indicate that the proposed framework has high success rate and good run time performance.

  4. 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.

  5. Anonymity communication VPN and Tor: a comparative study

    Science.gov (United States)

    Ramadhani, E.

    2018-03-01

    VPN and Tor is a technology based on anonymity communication. These two technologies have their advantage and disadvantage. The objective of this paper is to find the difference between VPN and Tor technologies by comparing their security of communication on the public network based on the CIA triad concept. The comparative study in this paper is based on the survey method. At last, the result of this paper is a recommendation on when to use a VPN and Tor to secure communication

  6. Privacy preserving data anonymization of spontaneous ADE reporting system dataset.

    Science.gov (United States)

    Lin, Wen-Yang; Yang, Duen-Chuan; Wang, Jie-Teng

    2016-07-18

    To facilitate long-term safety surveillance of marketing drugs, many spontaneously reporting systems (SRSs) of ADR events have been established world-wide. Since the data collected by SRSs contain sensitive personal health information that should be protected to prevent the identification of individuals, it procures the issue of privacy preserving data publishing (PPDP), that is, how to sanitize (anonymize) raw data before publishing. Although much work has been done on PPDP, very few studies have focused on protecting privacy of SRS data and none of the anonymization methods is favorable for SRS datasets, due to which contain some characteristics such as rare events, multiple individual records, and multi-valued sensitive attributes. We propose a new privacy model called MS(k, θ (*) )-bounding for protecting published spontaneous ADE reporting data from privacy attacks. Our model has the flexibility of varying privacy thresholds, i.e., θ (*) , for different sensitive values and takes the characteristics of SRS data into consideration. We also propose an anonymization algorithm for sanitizing the raw data to meet the requirements specified through the proposed model. Our algorithm adopts a greedy-based clustering strategy to group the records into clusters, conforming to an innovative anonymization metric aiming to minimize the privacy risk as well as maintain the data utility for ADR detection. Empirical study was conducted using FAERS dataset from 2004Q1 to 2011Q4. We compared our model with four prevailing methods, including k-anonymity, (X, Y)-anonymity, Multi-sensitive l-diversity, and (α, k)-anonymity, evaluated via two measures, Danger Ratio (DR) and Information Loss (IL), and considered three different scenarios of threshold setting for θ (*) , including uniform setting, level-wise setting and frequency-based setting. We also conducted experiments to inspect the impact of anonymized data on the strengths of discovered ADR signals. With all three

  7. Linking Health Records for Federated Query Processing

    Directory of Open Access Journals (Sweden)

    Dewri Rinku

    2016-07-01

    Full Text Available A federated query portal in an electronic health record infrastructure enables large epidemiology studies by combining data from geographically dispersed medical institutions. However, an individual’s health record has been found to be distributed across multiple carrier databases in local settings. Privacy regulations may prohibit a data source from revealing clear text identifiers, thereby making it non-trivial for a query aggregator to determine which records correspond to the same underlying individual. In this paper, we explore this problem of privately detecting and tracking the health records of an individual in a distributed infrastructure. We begin with a secure set intersection protocol based on commutative encryption, and show how to make it practical on comparison spaces as large as 1010 pairs. Using bigram matching, precomputed tables, and data parallelism, we successfully reduced the execution time to a matter of minutes, while retaining a high degree of accuracy even in records with data entry errors. We also propose techniques to prevent the inference of identifier information when knowledge of underlying data distributions is known to an adversary. Finally, we discuss how records can be tracked utilizing the detection results during query processing.

  8. An outcome study of Gamblers Anonymous.

    Science.gov (United States)

    Stewart, R M; Brown, R I

    1988-02-01

    Retrospective and prospective studies of a total sample of 232 attenders at groups of Gamblers Anonymous suggest that total abstinence from gambling was maintained by 8% of all comers at one year from first attendance and by 7% at two years.

  9. Fieldale-Collinsville Middle School: Banishing Anonymity

    Science.gov (United States)

    Principal Leadership, 2010

    2010-01-01

    It is no accident that the staff at Fieldale-Collinsville Middle School adopted a central tenet of "Breaking Ranks in the Middle"--to banish anonymity by creating a personalized learning environment for all of its students. The school was created six years ago when the four middle schools in Henry County, VA, were consolidated into two…

  10. 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.

  11. 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.

  12. 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...

  13. 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.

  14. Query containment in entity SQL

    OpenAIRE

    Rull Fort, Guillem; Bernstein, Philip A.; Garcia dos Santos, Ivo; Katsis, Yannis; Melnik, Sergey; Teniente López, Ernest

    2013-01-01

    We describe a software architecture we have developed for a constructive containment checker of Entity SQL queries defined over extended ER schemas expressed in Microsoft's Entity Data Model. Our application of interest is compilation of object-to-relational mappings for Microsoft's ADO.NET Entity Framework, which has been shipping since 2007. The supported language includes several features which have been individually addressed in the past but, to the best of our knowledge, they have not be...

  15. The Anonymity vs. Utility Dilemma

    Science.gov (United States)

    Bezzi, Michele; Pazzaglia, Jean-Christophe

    The number, the type of users and their usage of the internet, computers and phones have evolved considerably, due to the emergence of the web 2.0, the decreasing cost of portable devices, the expansion of wired and wireless internet access and the digitalization of the main entertainment media. Protecting the assets of service and software providers has been the main driver for the development of security solutions in the past ten years. However, the users/customers/citizen rights have been too often neglected since the risk related to the wrong usage of personal related information was not considered by the other stakeholders. Today, the Right to Privacy is appearing on everyone’s radar and factors as regulations, increasing number of news stories on privacy breaches, brand damages, are forcing organizations to address user privacy as a priority. In this paper, we will briefly review the main business drivers behind the raising of privacy concerns, and outline some of the current technology solutions to address privacy requirements. Finally, we will describe some of the future challenges in the area of privacy.

  16. 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.

  17. 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

  18. 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...

  19. 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.

  20. Gamblers Anonymous as a Recovery Pathway: A Scoping Review

    OpenAIRE

    Schuler, Andr?e; Ferentzy, Peter; Turner, Nigel E.; Skinner, Wayne; McIsaac, Kathryn E.; Ziegler, Carolyn P.; Matheson, Flora I.

    2016-01-01

    Given the preponderance of Gamblers Anonymous (GA), there has been relatively little effort to explore the existing evidence base on its effectiveness as a recovery approach for problem gambling. To remedy this gap in the literature we conducted a scoping review of the literature on mutual aid for individuals experiencing problem gambling published between 2002 and 2015. We searched 13 databases and reviewed reference lists and websites of relevant organizations. We reviewed records for eligi...

  1. 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…

  2. 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

  3. 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...

  4. Technologies for conceptual modelling and intelligent query formulation

    CSIR Research Space (South Africa)

    Alberts, R

    2008-11-01

    Full Text Available The aim of the project is to devise and evaluate algorithms, methodologies, techniques and interaction paradigms to build a tool for conceptual modelling and query management of complex data repositories based on a framework with solid formal...

  5. An introduction to XML query processing and keyword search

    CERN Document Server

    Lu, Jiaheng

    2013-01-01

    This book systematically and comprehensively covers the latest advances in XML data searching. It presents an extensive overview of the current query processing and keyword search techniques on XML data.

  6. 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...

  7. 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.

  8. Informed Traders as Liquidity Providers: Anonymity, Liquidity and Price Formation

    OpenAIRE

    Barbara Rindi

    2008-01-01

    The tendency to introduce anonymity into financial markets apparently runs counter to the theory supporting transparency. This paper studies the impact of pre-trade transparency on liquidity in a market where risk-averse traders accommodate the liquidity demand of noise traders. When some risk-averse investors become informed, an adverse selection problem ensues for the others, making them reluctant to supply liquidity. Hence the disclosure of traders' identities improves liquidity by mitigat...

  9. The Sniper Attack: Anonymously Deanonymizing and Disabling the Tor Network

    Science.gov (United States)

    2014-02-01

    attack is also similar to those that rely on misbehaving receivers and optimistic ACKs to bypass flow control protocol mechanisms [40]–[42]. In particular...thank the anonymous reviewers for their feedback and suggestions, Damon McCoy for discussions about misbehaving receivers and authenticated signals...ping-o-death. html. [40] S. Savage, N. Cardwell, D. Wetherall, and T. Anderson, “TCP Con- gestion Control with a Misbehaving Receiver,” ACM SIGCOMM CCR

  10. 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...

  11. k-Degree Anonymity Model for Social Network Data Publishing

    Directory of Open Access Journals (Sweden)

    MACWAN, K. R.

    2017-11-01

    Full Text Available Publicly accessible platform for social networking has gained special attraction because of its easy data sharing. Data generated on such social network is analyzed for various activities like marketing, social psychology, etc. This requires preservation of sensitive attributes before it becomes easily accessible. Simply removing the personal identities of the users before publishing data is not enough to maintain the privacy of the individuals. The structure of the social network data itself reveals much information regarding its users and their connections. To resolve this problem, k-degree anonymous method is adopted. It emphasizes on the modification of the graph to provide at least k number of nodes that contain the same degree. However, this approach is not efficient on a huge amount of social data and the modification of the original data fails to maintain data usefulness. In addition to this, the current anonymization approaches focus on a degree sequence-based graph model which leads to major modification of the graph topological properties. In this paper, we have proposed an improved k-degree anonymity model that retain the social network structural properties and also to provide privacy to the individuals. Utility measurement approach for community based graph model is used to verify the performance of the proposed technique.

  12. A Comparative Study on Two Typical Schemes for Securing Spatial-Temporal Top-k Queries in Two-Tiered Mobile Wireless Sensor Networks.

    Science.gov (United States)

    Ma, Xingpo; Liu, Xingjian; Liang, Junbin; Li, Yin; Li, Ran; Ma, Wenpeng; Qi, Chuanda

    2018-03-15

    A novel network paradigm of mobile edge computing, namely TMWSNs (two-tiered mobile wireless sensor networks), has just been proposed by researchers in recent years for its high scalability and robustness. However, only a few works have considered the security of TMWSNs. In fact, the storage nodes, which are located at the upper layer of TMWSNs, are prone to being attacked by the adversaries because they play a key role in bridging both the sensor nodes and the sink, which may lead to the disclosure of all data stored on them as well as some other potentially devastating results. In this paper, we make a comparative study on two typical schemes, EVTopk and VTMSN, which have been proposed recently for securing Top- k queries in TMWSNs, through both theoretical analysis and extensive simulations, aiming at finding out their disadvantages and advancements. We find that both schemes unsatisfactorily raise communication costs. Specifically, the extra communication cost brought about by transmitting the proof information uses up more than 40% of the total communication cost between the sensor nodes and the storage nodes, and 80% of that between the storage nodes and the sink. We discuss the corresponding reasons and present our suggestions, hoping that it will inspire the researchers researching this subject.

  13. Estimation of Anonymous Email Network Characteristics through Statistical Disclosure Attacks

    Directory of Open Access Journals (Sweden)

    Javier Portela

    2016-11-01

    Full Text Available Social network analysis aims to obtain relational data from social systems to identify leaders, roles, and communities in order to model profiles or predict a specific behavior in users’ network. Preserving anonymity in social networks is a subject of major concern. Anonymity can be compromised by disclosing senders’ or receivers’ identity, message content, or sender-receiver relationships. Under strongly incomplete information, a statistical disclosure attack is used to estimate the network and node characteristics such as centrality and clustering measures, degree distribution, and small-world-ness. A database of email networks in 29 university faculties is used to study the method. A research on the small-world-ness and Power law characteristics of these email networks is also developed, helping to understand the behavior of small email networks.

  14. Estimation of Anonymous Email Network Characteristics through Statistical Disclosure Attacks

    Science.gov (United States)

    Portela, Javier; García Villalba, Luis Javier; Silva Trujillo, Alejandra Guadalupe; Sandoval Orozco, Ana Lucila; Kim, Tai-Hoon

    2016-01-01

    Social network analysis aims to obtain relational data from social systems to identify leaders, roles, and communities in order to model profiles or predict a specific behavior in users’ network. Preserving anonymity in social networks is a subject of major concern. Anonymity can be compromised by disclosing senders’ or receivers’ identity, message content, or sender-receiver relationships. Under strongly incomplete information, a statistical disclosure attack is used to estimate the network and node characteristics such as centrality and clustering measures, degree distribution, and small-world-ness. A database of email networks in 29 university faculties is used to study the method. A research on the small-world-ness and Power law characteristics of these email networks is also developed, helping to understand the behavior of small email networks. PMID:27809275

  15. Efficient Asymmetric Index Encapsulation Scheme for Anonymous Content Centric Networking

    Directory of Open Access Journals (Sweden)

    Rong Ma

    2017-01-01

    Full Text Available Content Centric Networking (CCN is an effective communication paradigm that well matches the features of wireless environments. To be considered a viable candidate in the emerging wireless networks, despite the clear benefits of location-independent security, CCN must at least have parity with existing solutions for confidential and anonymous communication. This paper designs a new cryptographic scheme, called Asymmetric Index Encapsulation (AIE, that enables the router to test whether an encapsulated header matches the token without learning anything else about both of them. We suggest using the AIE as the core protocol of anonymous Content Centric Networking. A construction of AIE which strikes a balance between efficiency and security is given. The scheme is proved to be secure based on the DBDH assumption in the random oracle with tight reduction, while the encapsulated header and the token in our system consist of only three elements.

  16. An Anonymous Surveying Protocol via Greenberger-Horne-Zeilinger States

    Science.gov (United States)

    Naseri, Mosayeb; Gong, Li-Hua; Houshmand, Monireh; Matin, Laleh Farhang

    2016-10-01

    A new experimentally feasible anonymous survey protocol with authentication using Greenberger-Horne-Zeilinger (GHZ) entangled states is proposed. In this protocol, a chief executive officer (CEO) of a firm or company is trying to find out the effect of a possible action. In order to prepare a fair voting, the CEO would like to make an anonymous survey and is also interested in the total action for the whole company and he doesn't want to have a partial estimate for each department. In our proposal, there are two voters, Alice and Bob, voting on a question with a response of either "yes" or "no" and a tallyman, whose responsibility is to determine whether they have cast the same vote or not. In the proposed protocol the total response of the voters is calculated without revealing the actual votes of the voters.

  17. 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.

  18. 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.

  19. Effects of Framing Proximal Benefits of Quitting and Motivation to Quit as a Query on Communications About Tobacco Constituents.

    Science.gov (United States)

    Kowitt, Sarah; Sheeran, Paschal; Jarman, Kristen; Ranney, Leah M; Schmidt, Allison M; Huang, Li-Ling; Goldstein, Adam O

    2017-10-01

    Little is known on how to communicate messages on tobacco constituents to tobacco users. This study manipulated three elements of a message in the context of a theory-based communication campaign about tobacco constituents: (1) latency of response efficacy (how soon expected health benefits would accrue), (2) self-efficacy (confidence about quitting), and (3) interrogative cue ("Ready to be tobacco-free?"). Smokers (N = 1669, 55.4% women) were recruited via an online platform, and were randomized to a 3 (Latency of response efficacy) × 2 (Self-efficacy) × 2 (Interrogative cue) factorial design. The dependent variables were believability, credibility, perceived effectiveness of the communication message, and action expectancies (likelihood of seeking additional information and help with quitting). Latency of response efficacy influenced believability, perceived effectiveness, credibility, and action expectancies. In each case, scores were higher when specific health benefits were said to accrue within 1 month, as compared to general health benefits occurring in a few hours. The interrogative cue had a marginal positive effect on perceived effectiveness. The self-efficacy manipulation had no reliable effects, and there were no significant interactions among conditions. Smokers appear less persuaded by a communication message on constituents where general health benefits accrue immediately (within a few hours) than specific benefits over a longer timeframe (1 month). Additionally, smokers appeared to be more persuaded by messages with an interrogative cue. Such findings may help design more effective communication campaigns on tobacco constituents to smokers. This paper describes, for the first time, how components of tobacco constituent messages are perceived. We now know that smokers appear to be less persuaded by communication messages where general health benefits accrue immediately (within a few hours) than specific benefits over a longer timeframe (1 month

  20. 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.

  1. Academic freedom, public reactions, and anonymity.

    Science.gov (United States)

    Häyry, Matti

    2014-05-01

    Academic freedom can be defined as immunity against adverse reactions from the general public, designed to keep scholars unintimidated and productive even after they have published controversial ideas. Francesca Minerva claims that this notion of strict instrumental academic freedom is supported by Ronald Dworkin, and that anonymity would effectively defend the sphere of immunity implied by it. Against this, I argue that the idea defended by Minerva finds no support in the work by Dworkin referred to; that anonymity would not in most cases effectively protect the kind of immunity sought after; and that in some cases it would not even be desirable to protect scholars from public reactions to their controversial claims. © 2014 John Wiley & Sons Ltd.

  2. Yahtzee: an anonymized group level matching procedure.

    Science.gov (United States)

    Jones, Jason J; Bond, Robert M; Fariss, Christopher J; Settle, Jaime E; Kramer, Adam D I; Marlow, Cameron; Fowler, James H

    2013-01-01

    Researchers often face the problem of needing to protect the privacy of subjects while also needing to integrate data that contains personal information from diverse data sources. The advent of computational social science and the enormous amount of data about people that is being collected makes protecting the privacy of research subjects ever more important. However, strict privacy procedures can hinder the process of joining diverse sources of data that contain information about specific individual behaviors. In this paper we present a procedure to keep information about specific individuals from being "leaked" or shared in either direction between two sources of data without need of a trusted third party. To achieve this goal, we randomly assign individuals to anonymous groups before combining the anonymized information between the two sources of data. We refer to this method as the Yahtzee procedure, and show that it performs as predicted by theoretical analysis when we apply it to data from Facebook and public voter records.

  3. All or Nothing: The False Promise of Anonymity

    Directory of Open Access Journals (Sweden)

    Neil Walker

    2017-05-01

    Full Text Available In early 2016, the International Committee of Medical Journal Editors (ICMJE proposed that responsible sharing of de-identified individual-level data be required for clinical trials published in their affiliated journals. There would be a delay in implementing this policy to allow for the necessary informed consents to work their way through ethical review. Meanwhile, some researchers and policy makers have conflated the notions of de-identification and anonymity. The former is a process that seeks to mitigate disclosure risk though careful application of rules and statistical analysis, while the latter is an absolute state. The consequence of confusing the process and the state is profound. Extensions to the ICMJE proposal based on the presumed anonymity of data include: sharing unconsented data; sharing data without managing access, as Open Data; and proposals to sell data. This essay aims to show that anonymity (the state cannot be guaranteed by de-identification (the process, and so these extensions to the ICMJE proposal should be rejected on governance grounds, if no other. This is not as negative a position as it might seem, as other disciplines have been aware of these limitations and concomitant responsibilities for many years. The essay concludes with an example from social science of managed access strategies that could be adopted by the medical field.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. Enhancing physicians' use of Alcoholics Anonymous: Internet-based training.

    Science.gov (United States)

    Sellers, Brealyn; Galanter, Marc; Dermatis, Helen; Nachbar, Martin

    2005-01-01

    Alcoholics Anonymous is not yet fully employed by the medical community as a means to enhance patient outcome. The purpose of this study was to evaluate visitors' use of an Internet course on Alcoholics Anonymous, and to compare how various disciplines learned about, gained access to and participated in the course. Demographic information was collected from 414 visitors to the course. 64% of the 414 respondents received their last educational degree within the last 10 years, and had an interest in the topic of addiction prior to their accessing the site. 294 (71%) of those who accessed the course completed it, and those who accessed it learned about it from various sources other than print advertisement in professional journals. Within the 230 physician respondents, 143 (62%) were psychiatrists, 82 (78%) of whom learned about the Internet course via professional journal. Given the need for further training among physicians in the use of Alcoholics Anonymous, the Internet can be utilized to make information available to a large number of people. Because it allows the user to access information outside the traditional means, the barriers to its use are minimal, and it has the potential to effectively convey useful clinical information.

  9. 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.

  10. Securing the anonymity of content providers in the World Wide Web

    Science.gov (United States)

    Demuth, Thomas; Rieke, Andreas

    1999-04-01

    Nowadays the World Wide Web (WWW) is an established service used by people all over the world. Most of them do not recognize the fact that they reveal plenty of information about themselves or their affiliation and computer equipment to the providers of web pages they connect to. As a result, a lot of services offer users to access web pages unrecognized or without risk of being backtracked, respectively. This kind of anonymity is called user or client anonymity. But on the other hand, an equivalent protection for content providers does not exist, although this feature is desirable for many situations in which the identity of a publisher or content provider shall be hidden. We call this property server anonymity. We will introduce the first system with the primary target to offer anonymity for providers of information in the WWW. Beside this property, it provides also client anonymity. Based on David Chaum's idea of mixes and in relation to the context of the WWW, we explain the term 'server anonymity' motivating the system JANUS which offers both client and server anonymity.

  11. 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.

  12. 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.

  13. A framework for automatically checking anonymity with μ CRL

    OpenAIRE

    Chothia, T.; Orzan, S.M.; Pang, J.; Torabi Dashti, M.; Montanari, U.; Sannella, D.; Bruni, R.

    2007-01-01

    We present a powerful and flexible method for automatically checking anonymity in a possibilistic general-purpose process algebraic verification toolset. We propose new definitions of a choice anonymity degree and a player anonymity degree, to quantify the precision with which an intruder is able to single out the true originator of a given event or to associate the right event to a given protocol participant. We show how these measures of anonymity can be automatically calculated from a prot...

  14. Anonymous letters? DNA and fingerprints technologies combined to solve a case.

    Science.gov (United States)

    Barbaro, A; Cormaci, P; Teatino, A; La Marca, A; Barbaro, A

    2004-12-02

    Two brothers, living in two different cities, received two different anonymous letters. We performed latent prints development and DNA research on the letters and also on a glass used by a cousin suspected to be the letters' sender.

  15. 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.

  16. Deep web query interface understanding and integration

    CERN Document Server

    Dragut, Eduard C; Yu, Clement T

    2012-01-01

    There are millions of searchable data sources on the Web and to a large extent their contents can only be reached through their own query interfaces. There is an enormous interest in making the data in these sources easily accessible. There are primarily two general approaches to achieve this objective. The first is to surface the contents of these sources from the deep Web and add the contents to the index of regular search engines. The second is to integrate the searching capabilities of these sources and support integrated access to them. In this book, we introduce the state-of-the-art tech

  17. Downloading Multiple Records Using Query Strings

    Directory of Open Access Journals (Sweden)

    Adam Crymble

    2012-11-01

    Full Text Available Downloading a single record from a website is easy, but downloading many records at a time – an increasingly frequent need for a historian – is much more efficient using a programming language such as Python. In this lesson, we will write a program that will download a series of records from the Old Bailey Online using custom search criteria, and save them to a directory on our computer. This process involves interpreting and manipulating URL Query Strings. In this case, the tutorial will seek to download sources that contain references to people of African descent that were published in the Old Bailey Proceedings between 1700 and 1750.

  18. 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.

  19. 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...

  20. 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.

  1. 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....

  2. Yahtzee: an anonymized group level matching procedure.

    Directory of Open Access Journals (Sweden)

    Jason J Jones

    Full Text Available Researchers often face the problem of needing to protect the privacy of subjects while also needing to integrate data that contains personal information from diverse data sources. The advent of computational social science and the enormous amount of data about people that is being collected makes protecting the privacy of research subjects ever more important. However, strict privacy procedures can hinder the process of joining diverse sources of data that contain information about specific individual behaviors. In this paper we present a procedure to keep information about specific individuals from being "leaked" or shared in either direction between two sources of data without need of a trusted third party. To achieve this goal, we randomly assign individuals to anonymous groups before combining the anonymized information between the two sources of data. We refer to this method as the Yahtzee procedure, and show that it performs as predicted by theoretical analysis when we apply it to data from Facebook and public voter records.

  3. An Enhancing Security Research of Tor Anonymous Communication to Against DDos Attacks

    OpenAIRE

    Feng Tao; Zhao Ming-Tao

    2017-01-01

    Tor (The Second Onion Router) is modified by the first generation onion router and known as the most prevalent anonymous communication system. According to the advantage of low latency, high confidentiality of transmission content, high security of communication channels and et al., Tor is widely used in anonymous Web browsing, instant message and so on. However, the vulnerability and blemish of Tor affect system security. An identity and Signcryption-based concurrent signature scheme was use...

  4. 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.

  5. De-anonymizing Genomic Databases Using Phenotypic Traits

    Directory of Open Access Journals (Sweden)

    Humbert Mathias

    2015-06-01

    Full Text Available People increasingly have their genomes sequenced and some of them share their genomic data online. They do so for various purposes, including to find relatives and to help advance genomic research. An individual’s genome carries very sensitive, private information such as its owner’s susceptibility to diseases, which could be used for discrimination. Therefore, genomic databases are often anonymized. However, an individual’s genotype is also linked to visible phenotypic traits, such as eye or hair color, which can be used to re-identify users in anonymized public genomic databases, thus raising severe privacy issues. For instance, an adversary can identify a target’s genome using known her phenotypic traits and subsequently infer her susceptibility to Alzheimer’s disease. In this paper, we quantify, based on various phenotypic traits, the extent of this threat in several scenarios by implementing de-anonymization attacks on a genomic database of OpenSNP users sequenced by 23andMe. Our experimental results show that the proportion of correct matches reaches 23% with a supervised approach in a database of 50 participants. Our approach outperforms the baseline by a factor of four, in terms of the proportion of correct matches, in most scenarios. We also evaluate the adversary’s ability to predict individuals’ predisposition to Alzheimer’s disease, and we observe that the inference error can be halved compared to the baseline. We also analyze the effect of the number of known phenotypic traits on the success rate of the attack. As progress is made in genomic research, especially for genotype-phenotype associations, the threat presented in this paper will become more serious.

  6. Perspectives on the Use of “Anonymous” Discussion Forums in Undergraduate Education Courses / Perspectives sur l’usage des forums de discussion « partiellement anonymes » dans le cadre de cours universitaires de premier cycle en éducation

    Directory of Open Access Journals (Sweden)

    G. Michael Bowen

    2012-07-01

    Full Text Available This paper theorizes issues involved with conflicts between participation in on-line settings and real-world social commitments, such as has recently happened in schools with students using public discussion forums. We problematize how real-world social commitments negatively affect participation in online learning environments frequently used in classrooms. Drawing on interviews with, observations by, and written submissions from our students who participated in “hybrid” courses using an approach where identity was concealed in online discussions from other class participants, we discuss implications of this issue for evaluating forum submissions by students. Our analysis uses a cultural-historical activity theory framework to conceptualize implications from this anonymous forum approach and the resultant changes in participation in the learning environment. Cet article élabore une théorie des enjeux associés aux conflits entre la participation dans un environnement en ligne et les engagements sociaux réels, comme ce qui se produit actuellement dans les écoles, les étudiants se servant de forums publics de discussion pour leurs cours. Nous schématisons la façon dont les engagements sociaux réels ont des effets négatifs sur la participation aux environnements d’apprentissage en ligne fréquemment utilisés dans les salles de classe. À partir d’entrevues, d’observations et de communications écrites par les étudiants qui ont participé à nos cours « hybrides » en adoptant une approche par laquelle l’identité était gardée cachée des autres étudiants (mais non des instructeurs dans les discussions en ligne, nous discutons des implications de cet enjeu dans l’évaluation des soumissions des étudiants dans les forums. Notre analyse se sert d’un cadre théorique de l’activité historico-culturelle pour conceptualiser les implications de cette approche de forum « partiellement anonyme » et les changements de

  7. 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…

  8. 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

  9. 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

  10. 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

  11. 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…

  12. 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

  13. 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

  14. 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

  15. 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. ...

  16. The anonymity paradox in patient engagement: reputation, risk and web-based public feedback.

    Science.gov (United States)

    Speed, Ewen; Davison, Charlie; Gunnell, Caroline

    2016-06-01

    The UK National Health Service (NHS) has long espoused patient and public engagement. Recent years have seen increasing use of internet-based methods of collecting feedback about patient experience and public and staff views about NHS services and priorities. Often hailed as a means of facilitating participative democratic patient engagement, these processes raise a number of complex issues. A key aspect of it is the opportunity for comment to be made anonymously. Our research reveals an anonymity paradox whereby patients clearly demonstrate a perception that anonymity is a prerequisite for effective use of these feedback processes, whereas professionals demonstrate a perception that patient anonymity is a barrier to effective use. The risks of anonymity are constructed very differently by patients and professionals. Patient concerns around anonymity were not motivated by a general concern about a loss of privacy, but more that a positive identification might compromise future care. For professionals, concerns were voiced more around risks of reputational damage for specific practitioners or practices (in that anyone could say anything) and also that this anonymous feedback was available publicly and that it might go against the medical opinion of the professional. These concerns pointed to important differences in perceptions of patient and professional vulnerability. In the qualitative analysis that follows the key finding was that while anonymity makes service users feel less vulnerable, it can have the opposite effect on managers and clinical staff. This raises important implications for the use and utility of internet-based methods of collecting patient feedback. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  17. 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.

  18. Anonymity-Preserving Public-Key Encryption

    DEFF Research Database (Denmark)

    Kohlweiss, Markulf; Maurer, Ueli; Onete, Cristina

    2013-01-01

    security properties have been proposed. We investigate constructions as well as limitations for preserving receiver anonymity when using public-key encryption (PKE). We use the constructive cryptography approach by Maurer and Renner and interpret cryptographic schemes as constructions of a certain ideal...... literature (IND-CCA, key-privacy, weak robustness). We also show that a desirable stronger variant, preventing the adversary from selective ”trial-deliveries” of messages, is unfortunately unachievable by any PKE scheme, no matter how strong. The constructive approach makes the guarantees achieved...... by applying a cryptographic scheme explicit in the constructed (ideal) resource; this specifies the exact requirements for the applicability of a cryptographic scheme in a given context. It also allows to decide which of the existing security properties of such a cryptographic scheme are adequate...

  19. Effectiveness of Anonymization Methods in Preserving Patients' Privacy: A Systematic Literature Review.

    Science.gov (United States)

    Langarizadeh, Mostafa; Orooji, Azam; Sheikhtaheri, Abbas

    2018-01-01

    An ever growing for application of electronic health records (EHRs) has improved healthcare providers' communications, access to data for secondary use and promoted the quality of services. Patient's privacy has been changed to a great issue today since there are large loads of critical information in EHRs. Therefore, many privacy preservation techniques have been proposed and anonymization is a common one. This study aimed to investigate the effectiveness of anonymization in preserving patients' privacy. The articles published in the 2005-2016 were included. Pubmed, Cochrane, IEEE and ScienceDirect were searched with a variety of related keywords. Finally, 18 articles were included. In the present study, the relevant anonymization issues were investigated in four categories: secondary use of anonymized data, re-identification risk, anonymization effect on information extraction and inadequacy of current methods for different document types. The results revealed that though anonymization cannot reduce the risk of re-identification to zero, if implemented correctly, can manage to help preserve patient's privacy.

  20. 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.

  1. Categorical and Specificity Differences between User-Supplied Tags and Search Query Terms for Images. An Analysis of "Flickr" Tags and Web Image Search Queries

    Science.gov (United States)

    Chung, EunKyung; Yoon, JungWon

    2009-01-01

    Introduction: The purpose of this study is to compare characteristics and features of user supplied tags and search query terms for images on the "Flickr" Website in terms of categories of pictorial meanings and level of term specificity. Method: This study focuses on comparisons between tags and search queries using Shatford's categorization…

  2. Application of Machine Learning Algorithms for the Query Performance Prediction

    Directory of Open Access Journals (Sweden)

    MILICEVIC, M.

    2015-08-01

    Full Text Available This paper analyzes the relationship between the system load/throughput and the query response time in a real Online transaction processing (OLTP system environment. Although OLTP systems are characterized by short transactions, which normally entail high availability and consistent short response times, the need for operational reporting may jeopardize these objectives. We suggest a new approach to performance prediction for concurrent database workloads, based on the system state vector which consists of 36 attributes. There is no bias to the importance of certain attributes, but the machine learning methods are used to determine which attributes better describe the behavior of the particular database server and how to model that system. During the learning phase, the system's profile is created using multiple reference queries, which are selected to represent frequent business processes. The possibility of the accurate response time prediction may be a foundation for automated decision-making for database (DB query scheduling. Possible applications of the proposed method include adaptive resource allocation, quality of service (QoS management or real-time dynamic query scheduling (e.g. estimation of the optimal moment for a complex query execution.

  3. Generating and Executing Complex Natural Language Queries across Linked Data.

    Science.gov (United States)

    Hamon, Thierry; Mougin, Fleur; Grabar, Natalia

    2015-01-01

    With the recent and intensive research in the biomedical area, the knowledge accumulated is disseminated through various knowledge bases. Links between these knowledge bases are needed in order to use them jointly. Linked Data, SPARQL language, and interfaces in Natural Language question-answering provide interesting solutions for querying such knowledge bases. We propose a method for translating natural language questions in SPARQL queries. We use Natural Language Processing tools, semantic resources, and the RDF triples description. The method is designed on 50 questions over 3 biomedical knowledge bases, and evaluated on 27 questions. It achieves 0.78 F-measure on the test set. The method for translating natural language questions into SPARQL queries is implemented as Perl module available at http://search.cpan.org/ thhamon/RDF-NLP-SPARQLQuery.

  4. Bilastine in allergic rhinoconjunctivitis and urticaria: a practical approach to treatment decisions based on queries received by the medical information department

    Directory of Open Access Journals (Sweden)

    Amalia Leceta

    2017-02-01

    Full Text Available Background: Bilastine is a safe and effective commonly prescribed non-sedating H1-antihistamine approved for symptomatic treatment in patients with allergic disorders such as rhinoconjunctivitis and urticaria. It was evaluated in many patients throughout the clinical development required for its approval, but clinical trials generally exclude many patients who will benefit in everyday clinical practice (especially those with coexisting diseases and/or being treated with concomitant drugs. Following its introduction into clinical practice, the Medical Information Specialists at Faes Farma have received many practical queries regarding the optimal use of bilastine in different circumstances. Data sources and methods: Queries received by the Medical Information Department and the responses provided to senders of these queries. Results: The most frequent questions received by the Medical Information Department included the potential for drug-drug interactions with bilastine and commonly used agents such as anticoagulants (including the novel oral anticoagulants, antiretrovirals, antituberculosis regimens, corticosteroids, digoxin, oral contraceptives, and proton pump inhibitors. Most of these medicines are not usually allowed in clinical trials, and so advice needs to be based upon the pharmacological profiles of the drugs involved and expert opinion. The pharmacokinetic profile of bilastine appears favourable since it undergoes negligible metabolism and is almost exclusively eliminated via renal excretion, and it neither induces nor inhibits the activity of several isoenzymes from the CYP 450 system. Consequently, bilastine does not interact with cytochrome metabolic pathways. Other queries involved specific patient groups such as subjects with renal impairment, women who are breastfeeding or who are trying to become pregnant, and patients with other concomitant diseases. Interestingly, several questions related to topics that are well covered in

  5. Extending OLAP Querying to External Object

    DEFF Research Database (Denmark)

    Pedersen, Torben Bach; Shoshani, Arie; Gu, Junmin

    On-Line Analytical Processing (OLAP) systems based on a dimensional view of data have found widespread use in business applications and are being used increasingly in non-standard applications. These systems provide good performance and ease-of-use. However, the complex structures and relationships...... inherent in data in nonstandard applications are not accommodated well by OLAP systems. In contrast, object database systems are built to handle such complexity, but do not support OLAP-type querying well. This paper presents the concepts and techniques underlying a flexible, multi-model federated system...... that enables OLAP users to exploit simultaneously the features of OLAP and object systems. The system allows data to be handled using the most appropriate data model and technology: OLAP systems for dimensional data and object database systems for more complex, general data. Additionally, physical data...

  6. 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.

  7. Investigation in Query System Framework for High Energy Physics

    CERN Document Server

    Jatuphattharachat, Thanat

    2017-01-01

    We summarize an investigation in query system framework for HEP (High Energy Physics). Our work was an investigation on distributed server part of Femtocode, which is a query language that provides the ability for physicists to make plots and other aggregations in real-time. To make the system more robust and capable of processing large amount of data quickly, it is necessary to deploy the system on a redundant and distributed computing cluster. This project aims to investigate third party coordination and resource management frameworks which fit into the design of real-time distributed query system. Zookeeper, Mesos and Marathon are the main frameworks for this investigation. The results indicate that Zookeeper is good for job coordinator and job tracking as it provides robust, fast, simple and transparent read and write process for all connecting client across distributed Zookeeper server. Furthermore, it also supports high availability access and consistency guarantee within specific time bound.

  8. 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 ...

  9. 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.

  10. 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...

  11. 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...

  12. 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...

  13. Education on the Internet: Anonymity vs. Commitment.

    Science.gov (United States)

    Dreyfus, Hubert L.

    1998-01-01

    Argues that learning a skill requires the kind of commitment which is undermined by the Press (the Public) and the Internet, citing Soren Kierkegaard's "The Present Age", and states that learning by apprenticeship is impossible in cyberspace. Includes: aesthetic sphere--commitment to the enjoyment of sheer information; ethical…

  14. Querying Large Physics Data Sets Over an Information Grid

    CERN Document Server

    Baker, N; Kovács, Z; Le Goff, J M; McClatchey, R

    2001-01-01

    Optimising use of the Web (WWW) for LHC data analysis is a complex problem and illustrates the challenges arising from the integration of and computation across massive amounts of information distributed worldwide. Finding the right piece of information can, at times, be extremely time-consuming, if not impossible. So-called Grids have been proposed to facilitate LHC computing and many groups have embarked on studies of data replication, data migration and networking philosophies. Other aspects such as the role of 'middleware' for Grids are emerging as requiring research. This paper positions the need for appropriate middleware that enables users to resolve physics queries across massive data sets. It identifies the role of meta-data for query resolution and the importance of Information Grids for high-energy physics analysis rather than just Computational or Data Grids. This paper identifies software that is being implemented at CERN to enable the querying of very large collaborating HEP data-sets, initially...

  15. 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

  16. A high performance, ad-hoc, fuzzy query processing system for relational databases

    Science.gov (United States)

    Mansfield, William H., Jr.; Fleischman, Robert M.

    1992-01-01

    Database queries involving imprecise or fuzzy predicates are currently an evolving area of academic and industrial research. Such queries place severe stress on the indexing and I/O subsystems of conventional database environments since they involve the search of large numbers of records. The Datacycle architecture and research prototype is a database environment that uses filtering technology to perform an efficient, exhaustive search of an entire database. It has recently been modified to include fuzzy predicates in its query processing. The approach obviates the need for complex index structures, provides unlimited query throughput, permits the use of ad-hoc fuzzy membership functions, and provides a deterministic response time largely independent of query complexity and load. This paper describes the Datacycle prototype implementation of fuzzy queries and some recent performance results.

  17. 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.

  18. 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

  19. 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.

  20. 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

  1. 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.

  2. 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...

  3. a Novel Approach of Indexing and Retrieving Spatial Polygons for Efficient Spatial Region Queries

    Science.gov (United States)

    Zhao, J. H.; Wang, X. Z.; Wang, F. Y.; Shen, Z. H.; Zhou, Y. C.; Wang, Y. L.

    2017-10-01

    Spatial region queries are more and more widely used in web-based applications. Mechanisms to provide efficient query processing over geospatial data are essential. However, due to the massive geospatial data volume, heavy geometric computation, and high access concurrency, it is difficult to get response in real time. Spatial indexes are usually used in this situation. In this paper, based on k-d tree, we introduce a distributed KD-Tree (DKD-Tree) suitbable for polygon data, and a two-step query algorithm. The spatial index construction is recursive and iterative, and the query is an in memory process. Both the index and query methods can be processed in parallel, and are implemented based on HDFS, Spark and Redis. Experiments on a large volume of Remote Sensing images metadata have been carried out, and the advantages of our method are investigated by comparing with spatial region queries executed on PostgreSQL and PostGIS. Results show that our approach not only greatly improves the efficiency of spatial region query, but also has good scalability, Moreover, the two-step spatial range query algorithm can also save cluster resources to support a large number of concurrent queries. Therefore, this method is very useful when building large geographic information systems.

  4. A NOVEL APPROACH OF INDEXING AND RETRIEVING SPATIAL POLYGONS FOR EFFICIENT SPATIAL REGION QUERIES

    Directory of Open Access Journals (Sweden)

    J. H. Zhao

    2017-10-01

    Full Text Available Spatial region queries are more and more widely used in web-based applications. Mechanisms to provide efficient query processing over geospatial data are essential. However, due to the massive geospatial data volume, heavy geometric computation, and high access concurrency, it is difficult to get response in real time. Spatial indexes are usually used in this situation. In this paper, based on k-d tree, we introduce a distributed KD-Tree (DKD-Tree suitbable for polygon data, and a two-step query algorithm. The spatial index construction is recursive and iterative, and the query is an in memory process. Both the index and query methods can be processed in parallel, and are implemented based on HDFS, Spark and Redis. Experiments on a large volume of Remote Sensing images metadata have been carried out, and the advantages of our method are investigated by comparing with spatial region queries executed on PostgreSQL and PostGIS. Results show that our approach not only greatly improves the efficiency of spatial region query, but also has good scalability, Moreover, the two-step spatial range query algorithm can also save cluster resources to support a large number of concurrent queries. Therefore, this method is very useful when building large geographic information systems.

  5. 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.

  6. 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.

  7. 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.

  8. Vectorization vs. compilation in query execution

    NARCIS (Netherlands)

    J. Sompolski (Juliusz); M. Zukowski (Marcin); P.A. Boncz (Peter)

    2011-01-01

    textabstractCompiling database queries into executable (sub-) programs provides substantial benefits comparing to traditional interpreted execution. Many of these benefits, such as reduced interpretation overhead, better instruction code locality, and providing opportunities to use SIMD

  9. 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...

  10. 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

  11. Clean Air Markets - Allowances Query Wizard

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Allowances Query Wizard is part of a suite of Clean Air Markets-related tools that are accessible at http://camddataandmaps.epa.gov/gdm/index.cfm. The Allowances...

  12. Clean Air Markets - Compliance Query Wizard

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Compliance Query Wizard is part of a suite of Clean Air Markets-related tools that are accessible at http://ampd.epa.gov/ampd/. The Compliance module provides...

  13. 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...

  14. A Query System Implementation Case Study.

    Science.gov (United States)

    Hiser, Judith N.; Neil, M. Elizabeth

    1985-01-01

    The Department of Administrative Programming Services of Clemson University investigated products available in user-friendly retrieval systems. The test of INTELLECT, a natural language query system written by Artifical Intelligence Corporation, is described. (Author/MLW)

  15. Querying temporal databases via OWL 2 QL

    CSIR Research Space (South Africa)

    Klarman, S

    2014-06-01

    Full Text Available SQL:2011, the most recently adopted version of the SQL query language, has unprecedentedly standardized the representation of temporal data in relational databases. Following the successful paradigm of ontology-based data access, we develop a...

  16. 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

  17. Joint Top-K Spatial Keyword Query Processing

    DEFF Research Database (Denmark)

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

    2012-01-01

    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...

  18. Clauser-Horne-Shimony-Holt versus three-party pseudo-telepathy: on the optimal number of samples in device-independent quantum private query

    Science.gov (United States)

    Basak, Jyotirmoy; Maitra, Subhamoy

    2018-04-01

    In device-independent (DI) paradigm, the trustful assumptions over the devices are removed and CHSH test is performed to check the functionality of the devices toward certifying the security of the protocol. The existing DI protocols consider infinite number of samples from theoretical point of view, though this is not practically implementable. For finite sample analysis of the existing DI protocols, we may also consider strategies for checking device independence other than the CHSH test. In this direction, here we present a comparative analysis between CHSH and three-party Pseudo-telepathy game for the quantum private query protocol in DI paradigm that appeared in Maitra et al. (Phys Rev A 95:042344, 2017) very recently.

  19. 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.

  20. Vote to link: Recovering from misbehaving anonymous users

    NARCIS (Netherlands)

    Lueks, W.; Everts, M.H.; Hoepman, J.H.

    2016-01-01

    Service providers are often reluctant to support anonymous access, because this makes it hard to deal with misbehaving users. Anonymous blacklisting and reputation systems can help prevent misbehaving users from causing more damage. However, by the time the user is blocked or has lost reputation,

  1. Exploring query execution strategies for JIT vectorization and SIMD

    NARCIS (Netherlands)

    T.K. Gubner (Tim); P.A. Boncz (Peter)

    2017-01-01

    textabstractThis paper partially explores the design space for efficient query processors on future hardware that is rich in SIMD capabilities. It departs from two well-known approaches: (1) interpreted block-at-a-time execution (a.k.a. "vectorization") and (2) "data-centric" JIT compilation, as in

  2. Optimizing Aggregate SPARQL Queries Using Materialized RDF Views

    DEFF Research Database (Denmark)

    Ibragimov, Dilshod; Hose, Katja; Pedersen, Torben Bach

    2016-01-01

    , this paper proposes MARVEL (MAterialized Rdf Views with Entailment and incompLetness). The approach consists of a view selection algorithm based on an associated RDF-specific cost model, a view definition syntax, and an algorithm for rewriting SPARQL queries using materialized RDF views. The experimental...

  3. A Dynamic Extension of ATLAS Run Query Service

    CERN Document Server

    Buliga, Alexandru

    2015-01-01

    The ATLAS RunQuery is a primarily web-based service for the ATLAS community to access meta information about the data taking in a concise format. In order to provide a better user experience, the service was moved to use a new technology, involving concepts such as: Web Sockets, on demand data, client-side scripting, memory caching and parallelizing execution.

  4. 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...

  5. VMQL: A Visual Language for Ad-Hoc Model Querying

    DEFF Research Database (Denmark)

    Störrle, Harald

    2011-01-01

    In large scale model based development, analysis level models are more like knowledge bases than engineering artifacts. Their effectiveness depends, to a large degree, on the ability of domain experts to retrieve information from them ad hoc. For large scale models, however, existing query...

  6. Project Lefty: More Bang for the Search Query

    Science.gov (United States)

    Varnum, Ken

    2010-01-01

    This article describes the Project Lefty, a search system that, at a minimum, adds a layer on top of traditional federated search tools that will make the wait for results more worthwhile for researchers. At best, Project Lefty improves search queries and relevance rankings for web-scale discovery tools to make the results themselves more relevant…

  7. Multidimensional Data Model and Query Language for Informetrics.

    Science.gov (United States)

    Niemi, Timo; Hirvonen, Lasse; Jarvelin, Kalervo

    2003-01-01

    Discusses multidimensional data analysis, or online analytical processing (OLAP), which offer a single subject-oriented source for analyzing summary data based on various dimensions. Develops a conceptual/logical multidimensional model for supporting the needs of informetrics, including a multidimensional query language whose basic idea is to…

  8. CRYPTOGRAPHIC SECURE CLOUD STORAGE MODEL WITH ANONYMOUS AUTHENTICATION AND AUTOMATIC FILE RECOVERY

    Directory of Open Access Journals (Sweden)

    Sowmiya Murthy

    2014-10-01

    Full Text Available We propose a secure cloud storage model that addresses security and storage issues for cloud computing environments. Security is achieved by anonymous authentication which ensures that cloud users remain anonymous while getting duly authenticated. For achieving this goal, we propose a digital signature based authentication scheme with a decentralized architecture for distributed key management with multiple Key Distribution Centers. Homomorphic encryption scheme using Paillier public key cryptosystem is used for encrypting the data that is stored in the cloud. We incorporate a query driven approach for validating the access policies defined by an individual user for his/her data i.e. the access is granted to a requester only if his credentials matches with the hidden access policy. Further, since data is vulnerable to losses or damages due to the vagaries of the network, we propose an automatic retrieval mechanism where lost data is recovered by data replication and file replacement with string matching algorithm. We describe a prototype implementation of our proposed model.

  9. Formal Security-Proved Mobile Anonymous Authentication Protocols with Credit-Based Chargeability and Controllable Privacy

    Directory of Open Access Journals (Sweden)

    Chun-I Fan

    2016-06-01

    Full Text Available Smart mobile phones are widely popularized and advanced mobile communication services are provided increasingly often, such that ubiquitous computing environments will soon be a reality. However, there are many security threats to mobile networks and their impact on security is more serious than that in wireline networks owing to the features of wireless transmissions and the ubiquity property. The secret information which mobile users carry may be stolen by malicious entities. To guarantee the quality of advanced services, security and privacy would be important issues when users roam within various mobile networks. In this manuscript, an anonymous authentication scheme will be proposed to protect the security of the network system and the privacy of users. Not only does the proposed scheme provide mutual authentication between each user and the system, but also each user’s identity is kept secret against anyone else, including the system. Although the system anonymously authenticates the users, it can still generate correct bills to charge these anonymous users via a credit-based solution instead of debit-based ones. Furthermore, our protocols also achieve fair privacy which allows the judge to revoke the anonymity and trace the illegal users when they have misused the anonymity property, for example, if they have committed crimes. Finally, in this paper, we also carry out complete theoretical proofs on each claimed security property.

  10. VIGOR: Interactive Visual Exploration of Graph Query Results.

    Science.gov (United States)

    Pienta, Robert; Hohman, Fred; Endert, Alex; Tamersoy, Acar; Roundy, Kevin; Gates, Chris; Navathe, Shamkant; Chau, Duen Horng

    2018-01-01

    Finding patterns in graphs has become a vital challenge in many domains from biological systems, network security, to finance (e.g., finding money laundering rings of bankers and business owners). While there is significant interest in graph databases and querying techniques, less research has focused on helping analysts make sense of underlying patterns within a group of subgraph results. Visualizing graph query results is challenging, requiring effective summarization of a large number of subgraphs, each having potentially shared node-values, rich node features, and flexible structure across queries. We present VIGOR, a novel interactive visual analytics system, for exploring and making sense of query results. VIGOR uses multiple coordinated views, leveraging different data representations and organizations to streamline analysts sensemaking process. VIGOR contributes: (1) an exemplar-based interaction technique, where an analyst starts with a specific result and relaxes constraints to find other similar results or starts with only the structure (i.e., without node value constraints), and adds constraints to narrow in on specific results; and (2) a novel feature-aware subgraph result summarization. Through a collaboration with Symantec, we demonstrate how VIGOR helps tackle real-world problems through the discovery of security blindspots in a cybersecurity dataset with over 11,000 incidents. We also evaluate VIGOR with a within-subjects study, demonstrating VIGOR's ease of use over a leading graph database management system, and its ability to help analysts understand their results at higher speed and make fewer errors.

  11. A Database Query Processing Model in Peer-To-Peer Network ...

    African Journals Online (AJOL)

    Peer-to-peer databases are becoming more prevalent on the internet for sharing and distributing applications, documents, files, and other digital media. The problem associated with answering large-scale ad hoc analysis queries, aggregation queries, on these databases poses unique challenges. This paper presents an ...

  12. 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.

  13. Cardinality Estimation Algorithm in Large-Scale Anonymous Wireless Sensor Networks

    KAUST Repository

    Douik, Ahmed

    2017-08-30

    Consider a large-scale anonymous wireless sensor network with unknown cardinality. In such graphs, each node has no information about the network topology and only possesses a unique identifier. This paper introduces a novel distributed algorithm for cardinality estimation and topology discovery, i.e., estimating the number of node and structure of the graph, by querying a small number of nodes and performing statistical inference methods. While the cardinality estimation allows the design of more efficient coding schemes for the network, the topology discovery provides a reliable way for routing packets. The proposed algorithm is shown to produce a cardinality estimate proportional to the best linear unbiased estimator for dense graphs and specific running times. Simulation results attest the theoretical results and reveal that, for a reasonable running time, querying a small group of nodes is sufficient to perform an estimation of 95% of the whole network. Applications of this work include estimating the number of Internet of Things (IoT) sensor devices, online social users, active protein cells, etc.

  14. dCache, towards Federated Identities & Anonymized Delegation

    Science.gov (United States)

    Ashish, A.; Millar, AP; Mkrtchyan, T.; Fuhrmann, P.; Behrmann, G.; Sahakyan, M.; Adeyemi, O. S.; Starek, J.; Litvintsev, D.; Rossi, A.

    2017-10-01

    For over a decade, dCache has relied on the authentication and authorization infrastructure (AAI) offered by VOMS, Kerberos, Xrootd etc. Although the established infrastructure has worked well and provided sufficient security, the implementation of procedures and the underlying software is often seen as a burden, especially by smaller communities trying to adopt existing HEP software stacks [1]. Moreover, scientists are increasingly dependent on service portals for data access [2]. In this paper, we describe how federated identity management systems can facilitate the transition from traditional AAI infrastructure to novel solutions like OpenID Connect. We investigate the advantages offered by OpenID Connect in regards to ‘delegation of authentication’ and ‘credential delegation for offline access’. Additionally, we demonstrate how macaroons can provide a more fine-granular authorization mechanism that supports anonymized delegation.

  15. Cloud Based Data Protection in Anonymously Controlled SDN

    Directory of Open Access Journals (Sweden)

    Jian Shen

    2018-01-01

    Full Text Available Nowadays, Software Defined Network (SDN develops rapidly for its novel structure which separates the control plane and the data plane of network devices. Many researchers devoted themselves to the study of such a special network. However, some limitations restrict the development of SDN. On the one hand, the single controller in the conventional model bears all threats, and the corruption of it will result in network paralysis. On the other hand, the data will be increasing more in SDN switches in the data plane, while the storage space of these switches is limited. In order to solve the mentioned issues, we propose two corresponding protocols in this paper. Specifically, one is an anonymous protocol in the control plane, and the other is a verifiable outsourcing protocol in the data plane. The evaluation indicates that our protocol is correct, secure, and efficient.

  16. Anonymity versus privacy: selective information sharing in online cancer communities.

    Science.gov (United States)

    Frost, Jeana; Vermeulen, Ivar E; Beekers, Nienke

    2014-05-14

    Active sharing in online cancer communities benefits patients. However, many patients refrain from sharing health information online due to privacy concerns. Existing research on privacy emphasizes data security and confidentiality, largely focusing on electronic medical records. Patient preferences around information sharing in online communities remain poorly understood. Consistent with the privacy calculus perspective adopted from e-commerce research, we suggest that patients approach online information sharing instrumentally, weighing privacy costs against participation benefits when deciding whether to share certain information. Consequently, we argue that patients prefer sharing clinical information over daily life and identity information that potentially compromises anonymity. Furthermore, we explore whether patients' prior experiences, age, health, and gender affect perceived privacy costs and thus willingness to share information. The goal of the present study is to document patient preferences for sharing information within online health platforms. A total of 115 cancer patients reported sharing intentions for 15 different types of information, demographics, health status, prior privacy experiences, expected community utility, and privacy concerns. Factor analysis on the 15 information types revealed 3 factors coinciding with 3 proposed information categories: clinical, daily life, and identity information. A within-subject ANOVA showed a strong preference for sharing clinical information compared to daily life and identity information (F1,114=135.59, P=.001, η(2)=.93). Also, adverse online privacy experiences, age, and health status negatively affected information-sharing intentions. Female patients shared information less willingly. Respondents' information-sharing intentions depend on dispositional and situational factors. Patients share medical details more willingly than daily life or identity information. The results suggest the need to focus on

  17. Anonymity Versus Privacy: Selective Information Sharing in Online Cancer Communities

    Science.gov (United States)

    Vermeulen, Ivar E; Beekers, Nienke

    2014-01-01

    Background Active sharing in online cancer communities benefits patients. However, many patients refrain from sharing health information online due to privacy concerns. Existing research on privacy emphasizes data security and confidentiality, largely focusing on electronic medical records. Patient preferences around information sharing in online communities remain poorly understood. Consistent with the privacy calculus perspective adopted from e-commerce research, we suggest that patients approach online information sharing instrumentally, weighing privacy costs against participation benefits when deciding whether to share certain information. Consequently, we argue that patients prefer sharing clinical information over daily life and identity information that potentially compromises anonymity. Furthermore, we explore whether patients’ prior experiences, age, health, and gender affect perceived privacy costs and thus willingness to share information. Objective The goal of the present study is to document patient preferences for sharing information within online health platforms. Methods A total of 115 cancer patients reported sharing intentions for 15 different types of information, demographics, health status, prior privacy experiences, expected community utility, and privacy concerns. Results Factor analysis on the 15 information types revealed 3 factors coinciding with 3 proposed information categories: clinical, daily life, and identity information. A within-subject ANOVA showed a strong preference for sharing clinical information compared to daily life and identity information (F 1,114=135.59, P=.001, η2=.93). Also, adverse online privacy experiences, age, and health status negatively affected information-sharing intentions. Female patients shared information less willingly. Conclusions Respondents’ information-sharing intentions depend on dispositional and situational factors. Patients share medical details more willingly than daily life or identity

  18. 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.

  19. 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.

  20. 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.