WorldWideScience

Sample records for anonymized ons queries

  1. Evaluation of Anonymized ONS Queries

    CERN Document Server

    Garcia-Alfaro, Joaquin; Kranakis, Evangelos

    2009-01-01

    Electronic Product Code (EPC) is the basis of a pervasive infrastructure for the automatic identification of objects on supply chain applications (e.g., pharmaceutical or military applications). This infrastructure relies on the use of the (1) Radio Frequency Identification (RFID) technology to tag objects in motion and (2) distributed services providing information about objects via the Internet. A lookup service, called the Object Name Service (ONS) and based on the use of the Domain Name System (DNS), can be publicly accessed by EPC applications looking for information associated with tagged objects. Privacy issues may affect corporate infrastructures based on EPC technologies if their lookup service is not properly protected. A possible solution to mitigate these issues is the use of online anonymity. We present an evaluation experiment that compares the of use of Tor (The second generation Onion Router) on a global ONS/DNS setup, with respect to benefits, limitations, and latency.

  2. An Effective Clustering Approach to Web Query Log Anonymization

    CERN Document Server

    Fard, Amin Milani

    2010-01-01

    Web query log data contain information useful to research; however, release of such data can re-identify the search engine users issuing the queries. These privacy concerns go far beyond removing explicitly identifying information such as name and address, since non-identifying personal data can be combined with publicly available information to pinpoint to an individual. In this work we model web query logs as unstructured transaction data and present a novel transaction anonymization technique based on clustering and generalization techniques to achieve the k-anonymity privacy. We conduct extensive experiments on the AOL query log data. Our results show that this method results in a higher data utility compared to the state of-the-art transaction anonymization methods.

  3. User perspectives on query difficulty

    DEFF Research Database (Denmark)

    Lioma, Christina; Larsen, Birger; Schütze, Hinrich

    2011-01-01

    The difficulty of a user query can affect the performance of Information Retrieval (IR) systems. What makes a query difficult and how one may predict this is an active research area, focusing mainly on factors relating to the retrieval algorithm, to the properties of the retrieval data, or to sta......The difficulty of a user query can affect the performance of Information Retrieval (IR) systems. What makes a query difficult and how one may predict this is an active research area, focusing mainly on factors relating to the retrieval algorithm, to the properties of the retrieval data......, or to statistical and linguistic features of the queries that may render them difficult. This work addresses query difficulty from a different angle, namely the users’ own perspectives on query difficulty. Two research questions are asked: (1) Are users aware that the query they submit to an IR system may...

  4. Anonymizing Unstructured Data

    CERN Document Server

    Motwani, Rajeev

    2008-01-01

    In this paper we consider the problem of anonymizing datasets in which each individual is associated with a set of items that constitute private information about the individual. Illustrative datasets include market-basket datasets and search engine query logs. We formalize the notion of k-anonymity for set-valued data as a variant of the k-anonymity model for traditional relational datasets. We define an optimization problem that arises from this definition of anonymity and provide a constant factor approximation algorithm for the same. We evaluate our algorithms on the America Online query log dataset.

  5. A query index for continuous queries on RFID streaming data

    Institute of Scientific and Technical Information of China (English)

    Jaekwan PARK; Bonghee HONG; Chaehoon BAN

    2008-01-01

    RFID middleware collects and filters RFID streaming data to process applications' requests called continuous queries, because they are executed continuously during tag movement. Several approaches to building an index on queries rather than data records, called a query index, have been proposed to evaluate continuous queries over streaming data. EPCgiobal proposed an Event Cycle Specification (ECSpec) model, which is a de facto standard query interface for RFID applications. Continuous queries based on ECSpec consist of a large number of segments that represent the query conditions. The problem when using any of the existing query indexes on these continuous queries is that it takes a long time to build the index, because it is necessary to insert a large number of segments into the index. To solve this problem, we propose a transform method that converts a group of segments into compressed data. We also propose an efficient query index scheme for the transformed space. Comparing with existing query indexes, the performance of proposed index outperforms the others on various datasets.

  6. 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

  7. Anonymous Fingerprinting Based on Electronic Cash

    Institute of Scientific and Technical Information of China (English)

    CHENXiaofeng; ZHANGFangguo; WANGJilin; WANGYumin

    2003-01-01

    A new anonymous fingerprinting protocol based on the principle of electronic cash is proposed in this paper.Redistributing a data item is equal to doublespending electronic cash.Contrasting with the previous coin-based anonymous fingerprinting protocol,we use the real electronic cash to trace traitors instead of the "coins" which serve only as a cryptographic primitive and have no monetary value,so it is easily understood and the bank does not need key-distribution and registration to prepare the "coina".

  8. 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

  9. On the Utility of Anonymized Flow Traces for Anomaly Detection

    CERN Document Server

    Burkhart, Martin; May, Martin

    2008-01-01

    The sharing of network traces is an important prerequisite for the development and evaluation of efficient anomaly detection mechanisms. Unfortunately, privacy concerns and data protection laws prevent network operators from sharing these data. Anonymization is a promising solution in this context; however, it is unclear if the sanitization of data preserves the traffic characteristics or introduces artifacts that may falsify traffic analysis results. In this paper, we examine the utility of anonymized flow traces for anomaly detection. We quantitatively evaluate the impact of IP address anonymization, namely variations of permutation and truncation, on the detectability of large-scale anomalies. Specifically, we analyze three weeks of un-sampled and non-anonymized network traces from a medium-sized backbone network. We find that all anonymization techniques, except prefix-preserving permutation, degrade the utility of data for anomaly detection. We show that the degree of degradation depends to a large exten...

  10. Finding routes in anonymous sensor networks

    OpenAIRE

    Dutra, Renato C.; Barbosa, Valmir C

    2005-01-01

    We consider networks of anonymous sensors and address the problem of constructing routes for the delivery of information from a group of sensors in response to a query by a sink. In order to circumvent the restrictions imposed by anonymity, we rely on using the power level perceived by the sensors in the query from the sink. We introduce a simple distributed algorithm to achieve the building of routes to the sink and evaluate its performance by means of simulations.

  11. Octopus: A Secure and Anonymous DHT Lookup

    CERN Document Server

    Wang, Qiyan

    2012-01-01

    Distributed Hash Table (DHT) lookup is a core technique in structured peer-to-peer (P2P) networks. Its decentralized nature introduces security and privacy vulnerabilities for applications built on top of them; we thus set out to design a lookup mechanism achieving both security and anonymity, heretofore an open problem. We present Octopus, a novel DHT lookup which provides strong guarantees for both security and anonymity. Octopus uses attacker identification mechanisms to discover and remove malicious nodes, severely limiting an adversary's ability to carry out active attacks, and splits lookup queries over separate anonymous paths and introduces dummy queries to achieve high levels of anonymity. We analyze the security of Octopus by developing an event-based simulator to show that the attacker discovery mechanisms can rapidly identify malicious nodes with low error rate. We calculate the anonymity of Octopus using probabilistic modeling and show that Octopus can achieve near-optimal anonymity. We evaluate ...

  12. Comments onAnonymous reviewers” [“Anonymous reviews: Self-serving, counterproductive, and unacceptable”

    Science.gov (United States)

    Robinove, Charles J.

    Mryl Beck's Forum article denouncing anonymous reviews (Eos, 1 July 2003) is right on the money. Perhaps he read my letter in Applied Physics in 1990 also denouncing anonymous reviews.Some years ago, I received an anonymous review of a paper I had submitted for journal publication. The reviewer raised such interesting questions that I wanted to discuss them with him. I phoned the editor of the journal and asked if he would tell me the name of the reviewer. He politely declined, but when I told him I thought I recognized the handwriting of the reviewer and named him, he relented and said I was correct! I called the reviewer and he was generous enough to spend a wonderful hour on the phone with me discussing the paper. The paper was published with great consideration given to his ideas, much to its betterment. Now that's a reviewer whose interest is in improving the paper and helping the author, not just showing how smart he is or slapping down a junior colleague. The AGU motto,“unselfish cooperation in research,” can be well exemplified by those who wish to help rather than to tear down.

  13. Spatial information semantic query based on SPARQL

    Science.gov (United States)

    Xiao, Zhifeng; Huang, Lei; Zhai, Xiaofang

    2009-10-01

    How can the efficiency of spatial information inquiries be enhanced in today's fast-growing information age? We are rich in geospatial data but poor in up-to-date geospatial information and knowledge that are ready to be accessed by public users. This paper adopts an approach for querying spatial semantic by building an Web Ontology language(OWL) format ontology and introducing SPARQL Protocol and RDF Query Language(SPARQL) to search spatial semantic relations. It is important to establish spatial semantics that support for effective spatial reasoning for performing semantic query. Compared to earlier keyword-based and information retrieval techniques that rely on syntax, we use semantic approaches in our spatial queries system. Semantic approaches need to be developed by ontology, so we use OWL to describe spatial information extracted by the large-scale map of Wuhan. Spatial information expressed by ontology with formal semantics is available to machines for processing and to people for understanding. The approach is illustrated by introducing a case study for using SPARQL to query geo-spatial ontology instances of Wuhan. The paper shows that making use of SPARQL to search OWL ontology instances can ensure the result's accuracy and applicability. The result also indicates constructing a geo-spatial semantic query system has positive efforts on forming spatial query and retrieval.

  14. Path querying system on mobile devices

    Science.gov (United States)

    Lin, Xing; Wang, Yifei; Tian, Yuan; Wu, Lun

    2006-01-01

    Traditional approaches to path querying problems are not efficient and convenient under most circumstances. A more convenient and reliable approach to this problem has to be found. This paper is devoted to a path querying solution on mobile devices. By using an improved Dijkstra's shortest path algorithm and a natural language translating module, this system can help people find the shortest path between two places through their cell phones or other mobile devices. The chosen path is prompted in text of natural language, as well as a map picture. This system would be useful in solving best path querying problems and have potential to be a profitable business system.

  15. Theoretical Results on De-Anonymization via Linkage Attacks

    Directory of Open Access Journals (Sweden)

    Martin M. Merener

    2012-08-01

    Full Text Available Consider a database D with records containing history of individuals' transactions, that has been de-identified, i.e., the variables that uniquely associate records with individuals have been removed from the data. An adversary de-anonymizes D via a linkage attack if using some auxiliary information about a certain individual in the database, it can determine which record of D corresponds to such individual. One example of this is given in the article Robust De-anonymization of Large Sparse Datasets, by Narayanan and Shmatikov [19], which shows that an anonymized database containing records with ratings of different movies rented by customers of Netflix, could in fact be de-anonymized using very little auxiliary information, even with errors. Besides the heuristic de-anonymization of the Netflix database, Narayanan and Shmatikov provide interesting theoretical results about database de-anonymization that an adversary can produce under general conditions. In this article we revisit these theoretical results, and work them further. Our first contribution is to exhibit different simple cases in which the algorithm Scoreboard, meant to produce the theoretical de-anonymization in [19], fails to do so. By requiring 1-sim to be a pseudo-metric, and that the algorithm producing the de-anonymization outputs a record with minimum support among the candidates, we obtain and prove deanonymization results similar to those described in [19]. We then consider a new hypothesis, motivated by the fact (observed in heuristic de-anonymizations that when the auxiliary information contains values corresponding to rare attributes, the de-anonymization achieved is stronger. We formalize this using the notion on long tail [4], and give new theorems expressing the level of de-anonymization in terms of the parameters of the tail of the database D. The improvement in the deanonymization is reflected in the fact that when at least one value in the auxiliary information

  16. On the Feasibility of (Practical Commercial Anonymous Cloud Storage

    Directory of Open Access Journals (Sweden)

    Tobias Pulls

    2015-08-01

    Full Text Available Current de facto standard payment and billing models for commercial cloud storage services provide a plethora of information to the cloud provider about its clients. This leads to a hostile environment when seen from a privacy perspective. Motivated by recently leaked facts about large scale governmental surveillance efforts as well as the lack of privacy-preserving measures in existing commercial cloud storage services, in this paper, we investigate the feasibility of so called anonymous cloud storage services which require user payment (which we call commercial anonymous cloud storage. Anonymity in this context can be seen as the absence of information to uniquely identify a provider's client that is storing and manipulating data at the provider while at the same time still allowing fair billing, for both, the clients and the cloud provider. Although encrypting data prior to outsourcing helps to protect data privacy and can be achieved without the cloud provider's consent, the issues we are interested in, do not seem to be achievable that easily. However, while various measures for the latter issue, i.e., realizing access privacy, have been studied in the past, the role of privacy in context of billing and payment for cloud storage has, until now, remained unexplored. We therefore introduce an abstract model for commercial cloud storage services to define various types of anonymous cloud storage, study several payment and billing models for cloud storage services and their impact on the anonymity of the service's clients. Moreover, we discuss several solutions to provide anonymity within the different models. Our findings highlight the importance of anonymous payment for the practical deployment of commercial privacy-friendly cloud storage services. Furthermore, we provide directions for future work in some settings, i.e., when anonymous payment is not available, as interesting open challenges.

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

    Science.gov (United States)

    Zhang, Haitao; Chen, Zewei; 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

  18. Search Result Diversification Based on Query Facets

    Institute of Scientific and Technical Information of China (English)

    胡莎; 窦志成; 王晓捷; 继荣

    2015-01-01

    In search engines, different users may search for different information by issuing the same query. To satisfy more users with limited search results, search result diversification re-ranks the results to cover as many user intents as possible. Most existing intent-aware diversification algorithms recognize user intents as subtopics, each of which is usually a word, a phrase, or a piece of description. In this paper, we leverage query facets to understand user intents in diversification, where each facet contains a group of words or phrases that explain an underlying intent of a query. We generate subtopics based on query facets and propose faceted diversification approaches. Experimental results on the public TREC 2009 dataset show that our faceted approaches outperform state-of-the-art diversification models.

  19. 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.

  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. Query Expansion Based on Clustered Results

    CERN Document Server

    Liu, Ziyang; Chen, Yi

    2011-01-01

    Query expansion is a functionality of search engines that suggests a set of related queries for a user-issued keyword query. Typical corpus-driven keyword query expansion approaches return popular words in the results as expanded queries. Using these approaches, the expanded queries may correspond to a subset of possible query semantics, and thus miss relevant results. To handle ambiguous queries and exploratory queries, whose result relevance is difficult to judge, we propose a new framework for keyword query expansion: we start with clustering the results according to user specified granularity, and then generate expanded queries, such that one expanded query is generated for each cluster whose result set should ideally be the corresponding cluster. We formalize this problem and show its APX-hardness. Then we propose two efficient algorithms named iterative single-keyword refinement and partial elimination based convergence, respectively, which effectively generate a set of expanded queries from clustered r...

  2. Effects of Help, Anonymity, and Privacy on Children's Academic Expectations.

    Science.gov (United States)

    Bird, Lisa

    This study examined the effect of three aspects of the testing context--physical privacy, anonymity, and offers of help from a tester--on children's expectations. Performance of 96 11-year-old boys and girls on a pictorial recall memory task in a simulated test was evaluated. The subjects were divided into eight different groups varying on the…

  3. Query Representation with Global Consistency on User Click Graph

    OpenAIRE

    Zhang, Daqiang; Zhu, Rongbo; Men, Shuqiqiu; Raychoudhury, Vaskar

    2013-01-01

    Extensive research has been conducted on query log analysis. A query log is generally represented as a bipartite graph on a query set and a URL set. Most of the traditional methods used the raw click frequency to weigh the link between a query and a URL on the click graph. In order to address the disadvantages of raw click frequency, researchers proposed the entropy-biased model, which incorporates raw click frequency with inverse query frequency of the URL as the weighting scheme for query r...

  4. AATCT: Anonymously Authenticated Transmission on the Cloud with Traceability

    Directory of Open Access Journals (Sweden)

    Maged Hamada Ibrahim

    2015-09-01

    Full Text Available In Cloud computing, anonymous authentication is an important service that must be available to users in the Cloud. Users have the right to remain anonymous as long as they behave honestly. However, in case a malicious behavior is detected, the system – under court order – must be able to trace the user to his clear identity. Most of the proposed authentication schemes for the Cloud are either password-based authentication schemes that are vulnerable to offline dictionary attacks, or biometric-based authentication schemes that take a long time of execution specially in case of high security requirements. In this paper, we propose an efficient and secure scheme to non-interactively authenticate the users on the Cloud to the remote servers while preserving their anonymity. In case of accusations, the registration authority is able to trace any user to his clear identity. We avoid using low entropy passwords or biometric mechanisms, instead, we employ pseudonym systems in our design. The computation complexity and storage requirements are efficient and suitable to be implemented on smart cards/devices. Our proposed scheme withstands challenging adversarial attacks such as, stolen databases attacks, databases insertion attacks, impersonation attacks, replay attacks and malicious users/servers collaboration attacks.

  5. Result Diversification Based on Query-Specific Cluster Ranking

    NARCIS (Netherlands)

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

    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

  6. Result diversification based on query-specific cluster ranking

    NARCIS (Netherlands)

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

    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

  7. Complex transitive closure queries on a fragmented graph

    NARCIS (Netherlands)

    Houtsma, Maurice A.W.; Apers, Peter M.G.; Ceri, Stefano; Abiteboul, Serge; Kanellakis, Paris C.

    1990-01-01

    In this paper we study the reformulation of transitive closure queries on a fragmented graph. We split a query into several subqueries, each requiring only a fragment of the graph. We prove this reformulation to be correct for shortest path and bill of material queries. Here we describe the reformul

  8. 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).

  9. Quantum election scheme based on anonymous quantum key distribution

    International Nuclear Information System (INIS)

    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)

  10. Quantum election scheme based on anonymous quantum key distribution

    Institute of Scientific and Technical Information of China (English)

    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.

  11. 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...

  12. Multidimensional Data Querying on Tree-Structured Overlay

    Institute of Scientific and Technical Information of China (English)

    XU Lizhen; WANG Shiyuan

    2006-01-01

    Multidimensional data query has been gaining much interest in database research communities in recent years, yet many of the existing studies focus mainly on centralized systems.A solution to querying in Peer-to-Peer(P2P) environment was proposed to achieve both low processing cost in terms of the number of peers accessed and search messages and balanced query loads among peers.The system is based on a balanced tree structured P2P network.By partitioning the query space intelligently, the amount of query forwarding is effectively controlled, and the number of peers involved and search messages are also limited.Dynamic load balancing can be achieved during space partitioning and query resolving.Extensive experiments confirm the effectiveness and scalability of our algorithms on P2P networks.

  13. 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...

  14. 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.

  15. Research on land information web query service for public

    Science.gov (United States)

    Liang, Dongdong; Li, Lin; Song, Pingchao; Cheng, Yang; Mei, Song; Min, Yuan

    2009-10-01

    With economics developing fast and internet spreading extensively, the public strongly desire to know about land information. Especially, the policy, Land registration information available to the public inquiry approach, has been executed since March 1st, 2003, which gives the Land Department with guidance to build land information web query service for public. Land information web query service for public requires Land Management Department to provide land registration information which contains attribute and graphics information. When it comes to querying attribute information, precise and fuzzy query methods are commonly used in realistic applications. To improve the speed and accuracy of fuzzy query, Chinese word segmentation method is currently used. Especially, there is no previous example by this method used in cadastre information inquiry. Meanwhile, as for querying lands' spatial information, it is necessary to query attribute information before retrieving the actual graphics information. Then turning to the map service, eagle eye can show which part of whole cadastre map the specified cadastre land located in. But it is obvious the display speed of eagle eye is not as fast as that of cadastre map. Hence, we try to implement the multi-level query with frame selection on cadastre map and identify the different cadastre land with different colors, as eagle eye's display and panning speed are also accelerated. The accomplishments of our research have been applied to Land information query system of Ningbo. It is hoped that the solutions in this system will help to develop and study analogous issues.

  16. 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...

  17. On the query complexity of finding a local maximum point

    NARCIS (Netherlands)

    Rastsvelaev, A.L.; Beklemishev, L.D.

    2008-01-01

    We calculate the minimal number of queries sufficient to find a local maximum point of a functiun on a discrete interval for a model with M parallel queries, M≥1. Matching upper and lower bounds are obtained. The bounds are formulated in terms of certain Fibonacci type sequences of numbers.

  18. On the Definitions of Anonymity for Ring Signatures

    Science.gov (United States)

    Ohkubo, Miyako; Abe, Masayuki

    This paper studies the relations among several definitions of anonymity for ring signature schemes in the same attack environment. It is shown that one intuitive and two technical definitions we consider are asymptotically equivalent, and the indistinguishability-based technical definition is the strongest, i. e., the most secure when achieved, when the exact reduction cost is taken into account. We then extend our result to the threshold case where a subset of members cooperate to create a signature. The threshold setting makes the notion of anonymity more complex and yields a greater variety of definitions. We explore several notions and observe certain relation does not seem hold unlike the simple single-signer case. Nevertheless, we see that an indistinguishability-based definition is the most favorable in the threshold case. We also study the notion of linkability and present a simple scheme that achieves both anonymity and linkability.

  19. Against anonymity.

    Science.gov (United States)

    Baker, Robert

    2014-05-01

    In 'New Threats to Academic Freedom' Francesca Minerva argues that anonymity for the authors of controversial articles is a prerequisite for academic freedom in the Internet age. This argument draws its intellectual and emotional power from the author's account of the reaction to the on-line publication of ' After-birth abortion: why should the baby live?'--an article that provoked cascades of hostile postings and e-mails. Reflecting on these events, Minerva proposes that publishers should offer the authors of controversial articles the option of publishing their articles anonymously. This response reviews the history of anonymous publication and concludes that its reintroduction in the Internet era would recreate problems similar to those that led print journals to abandon the practice: corruption of scholarly discourse by invective and hate speech, masked conflicts of interest, and a diminution of editorial accountability. It also contends that Minerva misreads the intent of the hostile e-mails provoked by 'After-birth abortion,' and that ethicists who publish controversial articles should take responsibility by dialoguing with their critics--even those whose critiques are emotionally charged and hostile.

  20. Against anonymity.

    Science.gov (United States)

    Baker, Robert

    2014-05-01

    In 'New Threats to Academic Freedom' Francesca Minerva argues that anonymity for the authors of controversial articles is a prerequisite for academic freedom in the Internet age. This argument draws its intellectual and emotional power from the author's account of the reaction to the on-line publication of ' After-birth abortion: why should the baby live?'--an article that provoked cascades of hostile postings and e-mails. Reflecting on these events, Minerva proposes that publishers should offer the authors of controversial articles the option of publishing their articles anonymously. This response reviews the history of anonymous publication and concludes that its reintroduction in the Internet era would recreate problems similar to those that led print journals to abandon the practice: corruption of scholarly discourse by invective and hate speech, masked conflicts of interest, and a diminution of editorial accountability. It also contends that Minerva misreads the intent of the hostile e-mails provoked by 'After-birth abortion,' and that ethicists who publish controversial articles should take responsibility by dialoguing with their critics--even those whose critiques are emotionally charged and hostile. PMID:24724540

  1. 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 ...

  2. 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 cue

  3. 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...

  4. The retrieval effectiveness of search engines on navigational queries

    OpenAIRE

    Lewandowski, Dirk

    2011-01-01

    Purpose - To test major Web search engines on their performance on navigational queries, i.e. searches for homepages. Design/methodology/approach - 100 real user queries are posed to six search engines (Google, Yahoo, MSN, Ask, Seekport, and Exalead). Users described the desired pages, and the results position of these is recorded. Measured success N and mean reciprocal rank are calculated. Findings - Performance of the major search engines Google, Yahoo, and MSN is best, with around 90 perce...

  5. Study on consistent query answering in inconsistent databases

    Institute of Scientific and Technical Information of China (English)

    XIE Dong; YANG Luming

    2007-01-01

    Consistent query answering is an approach to retrieving consistent answers over databases that might be inconsistent with respect to some given integrity constraints The approach is based on a concept of repair.This paper surveys several recent researches on obtaining consistent information from inconsistent databases,such as the underlying semantic model,a number of approaches to computing consistent query answers and the computational complexity of this problem.Furthermore,the work outlines potential research directions in this area.

  6. Data Processing on Database Management Systems with Fuzzy Query

    Science.gov (United States)

    Şimşek, Irfan; Topuz, Vedat

    In this study, a fuzzy query tool (SQLf) for non-fuzzy database management systems was developed. In addition, samples of fuzzy queries were made by using real data with the tool developed in this study. Performance of SQLf was tested with the data about the Marmara University students' food grant. The food grant data were collected in MySQL database by using a form which had been filled on the web. The students filled a form on the web to describe their social and economical conditions for the food grant request. This form consists of questions which have fuzzy and crisp answers. The main purpose of this fuzzy query is to determine the students who deserve the grant. The SQLf easily found the eligible students for the grant through predefined fuzzy values. The fuzzy query tool (SQLf) could be used easily with other database system like ORACLE and SQL server.

  7. On the Feasibility of (Practical) Commercial Anonymous Cloud Storage

    OpenAIRE

    Tobias Pulls; Daniel Slamanig

    2015-01-01

    Current de facto standard payment and billing models for commercial cloud storage services provide a plethora of information to the cloud provider about its clients. This leads to a hostile environment when seen from a privacy perspective. Motivated by recently leaked facts about large scale governmental surveillance efforts as well as the lack of privacy-preserving measures in existing commercial cloud storage services, in this paper, we investigate the feasibility of so called anonymous clo...

  8. gSketch: On Query Estimation in Graph Streams

    CERN Document Server

    Zhao, Peixiang; Wang, Min

    2011-01-01

    Many dynamic applications are built upon large network infrastructures, such as social networks, communication networks, biological networks and the Web. Such applications create data that can be naturally modeled as graph streams, in which edges of the underlying graph are received and updated sequentially in a form of a stream. It is often necessary and important to summarize the behavior of graph streams in order to enable effective query processing. However, the sheer size and dynamic nature of graph streams present an enormous challenge to existing graph management techniques. In this paper, we propose a new graph sketch method, gSketch, which combines well studied synopses for traditional data streams with a sketch partitioning technique, to estimate and optimize the responses to basic queries on graph streams. We consider two different scenarios for query estimation: (1) A graph stream sample is available; (2) Both a graph stream sample and a query workload sample are available. Algorithms for differen...

  9. PHENOMENAL EXPLORATION INTO IMPACT OF ANONYMITY ON LAW AND ORDER IN CYBERSPACE

    OpenAIRE

    Li, Xingan

    2015-01-01

    While information systems provide modern society with great convenience, it also poses new problems in maintaining social order. One of its negative influences is the anonymity of cyberspace, which makes identity tracing a noteworthy predicament which poses obstacles in detection and investigations. It has been found that cyber anonymity has critical impacts on criminal motivation, and the phenomena of victimization, and should be tackled on different layers including technology and law enfor...

  10. 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.

  11. Secure Nearest Neighbor Query on Crowd-Sensing Data.

    Science.gov (United States)

    Cheng, Ke; Wang, Liangmin; Zhong, Hong

    2016-01-01

    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. PMID:27669253

  12. 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.

  13. Efficient Execution of Multiple Queries on Deep Memory Hierarchy

    Institute of Scientific and Technical Information of China (English)

    Yan Zhang; Zhi-Feng Chen; Yuan-Yuan Zhou

    2007-01-01

    This paper proposes a complementary novel idea, called MiniTasking to further reduce the number of cachemisses by improving the data temporal locality for multiple concurrent queries. Our idea is based on the observation that, inmany workloads such as decision support systems (DSS), there is usually significant amount of data sharing among differentconcurrent queries. MiniTasking exploits such data sharing to improve data temporal locality by scheduling query executionat three levels: query level batching, operator level grouping and mini-task level scheduling. The experimental results withvarious types of concurrent TPC-H query workloads show that, with the traditional N-ary Storage Model (NSM) layout,MiniTasking significantly reduces the L2 cache misses by up to 83%, and thereby achieves 24% reduction in execution time.With the Partition Attributes Across (PAX) layout, MiniTasking further reduces the cache misses by 65% and the executiontime by 9%. For the TPC-H throughput test workload, MiniTasking improves the end performance up to 20%.

  14. On the Fly Query Entity Decomposition Using Snippets

    CERN Document Server

    Brenes, David J; Garcia, Rodrigo

    2010-01-01

    One of the most important issues in Information Retrieval is inferring the intents underlying users' queries. Thus, any tool to enrich or to better contextualized queries can proof extremely valuable. Entity extraction, provided it is done fast, can be one of such tools. Such techniques usually rely on a prior training phase involving large datasets. That training is costly, specially in environments which are increasingly moving towards real time scenarios where latency to retrieve fresh informacion should be minimal. In this paper an `on-the-fly' query decomposition method is proposed. It uses snippets which are mined by means of a na\\"ive statistical algorithm. An initial evaluation of such a method is provided, in addition to a discussion on its applicability to different scenarios.

  15. Query Translation on the Fly in Deep Web Integration

    Institute of Scientific and Technical Information of China (English)

    JIANG Fangjiao; JIA Linlin; MENG Xiaofeng

    2007-01-01

    To facilitate users to access the desired information,many researches have dedicated to the Deep Web (i.e. Web databases) integration. We focus on query translation which is an important part of the Deep Web integration. Our aim is to construct automatically a set of constraints mapping rules so that the system can translate the query from the integrated interface to the Web database interfaces based on them. We construct a concept hierarchy for the attributes of the query interfaces, especially, store the synonyms and the types (e.g. Number, Text, etc.) for every concept.At the same time, we construct the data hierarchies for some concepts if necessary. Then we present an algorithm to generate the constraint mapping rules based on these hierarchies. The approach is suitable for the scalability of such application and can be extended easily from one domain to another for its domain independent feature. The results of experiment show its effectiveness and efficiency.

  16. 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...

  17. Semantic Query Mechanism on Peer to Peer XML- Based Information Systems

    Institute of Scientific and Technical Information of China (English)

    JIANG Min; HUANG Yi; GU Jinguang; HE Guiming

    2006-01-01

    To enable accessing web information at semantic level, this paper develops a semantic query rewriting mechanism on peer to peer XISs with complex ontology mapping technology. It discusses the patterns of complex ontology mappings at first, and the ontology-based query mechanism in peer to peer environment. The extension of XML query algebra and XML query rewriting mechanism are dissussed in detail.

  18. Efficient Path Query and Reasoning Method Based on Rare Axis

    Institute of Scientific and Technical Information of China (English)

    姜洋; 冯志勇; 王鑫马晓宁

    2015-01-01

    A new concept of rare axis based on statistical facts is proposed, and an evaluation algorithm is designed thereafter. For the nested regular expressions containing rare axes, the proposed algorithm can reduce its evaluation complexity from polynomial time to nearly linear time. The distributed technique is also employed to construct the navigation axis indexes for resource description framework (RDF) graph data. Experiment results in DrugBank and BioGRID show that this method can improve the query efficiency significantly while ensuring the accuracy and meet the query requirements on Web-scale RDF graph data.

  19. 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...

  20. 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....../O complexity and O(N + Q) space, where M is the size of the main memory and B is the block size. This is a factor of O(log M /B N) improvement in space complexity over the previous solutions. We also show that an instance of the batched dynamic RMQ problem with N updates and Q queries can be solved in O ( N...

  1. On Statistical Query Sampling and NMR Quantum Computing

    CERN Document Server

    Blum, A S; Blum, Avrim; Yang, Ke

    2003-01-01

    We introduce a ``Statistical Query Sampling'' model, in which the goal of an algorithm is to produce an element in a hidden set $Ssubseteqbit^n$ with reasonable probability. The algorithm gains information about $S$ through oracle calls (statistical queries), where the algorithm submits a query function $g(cdot)$ and receives an approximation to $Pr_{x in S}[g(x)=1]$. We show how this model is related to NMR quantum computing, in which only statistical properties of an ensemble of quantum systems can be measured, and in particular to the question of whether one can translate standard quantum algorithms to the NMR setting without putting all of their classical post-processing into the quantum system. Using Fourier analysis techniques developed in the related context of {em statistical query learning}, we prove a number of lower bounds (both information-theoretic and cryptographic) on the ability of algorithms to produces an $xin S$, even when the set $S$ is fairly simple. These lower bounds point out a difficu...

  2. Research on Extension of Sparql Ontology Query Language Considering the Computation of Indoor Spatial Relations

    Science.gov (United States)

    Li, C.; Zhu, X.; Guo, W.; Liu, Y.; Huang, H.

    2015-05-01

    A method suitable for indoor complex semantic query considering the computation of indoor spatial relations is provided According to the characteristics of indoor space. This paper designs ontology model describing the space related information of humans, events and Indoor space objects (e.g. Storey and Room) as well as their relations to meet the indoor semantic query. The ontology concepts are used in IndoorSPARQL query language which extends SPARQL syntax for representing and querying indoor space. And four types specific primitives for indoor query, "Adjacent", "Opposite", "Vertical" and "Contain", are defined as query functions in IndoorSPARQL used to support quantitative spatial computations. Also a method is proposed to analysis the query language. Finally this paper adopts this method to realize indoor semantic query on the study area through constructing the ontology model for the study building. The experimental results show that the method proposed in this paper can effectively support complex indoor space semantic query.

  3. Impact of Anonymity on Information Sharing through Internal Psychological Processes: A Case of South Korean Online Communities

    OpenAIRE

    Ho Lee; Jaewon Choi; Kyung Kyu Kim; Ae Ri Lee

    2014-01-01

    Many web users post their opinions and information without revealing their identities (i.e., demographics, social standing, and/or expertise); anonymity has become a common form of information exchange in online communities such as social media sites and Internet forums. In the meantime, negative social consequences have resulted from anonymous activities in online communities. Existing literature reports largely mixed results about the impact of online anonymity on online community outcomes....

  4. Lower Bounds on Quantum Query Complexity

    NARCIS (Netherlands)

    P. Hoyer; R. Spalek

    2005-01-01

    Shor's and Grover's famous quantum algorithms for factoring and searching show that quantum computers can solve certain computational problems significantly faster than any classical computer. We discuss here what quantum computers cannot do, and specifically how to prove limits on their computation

  5. Anonymous Gossiping

    CERN Document Server

    Datta, Anwitaman

    2010-01-01

    In this paper we introduce a novel gossiping primitive to support privacy preserving data analytics (PPDA). In contrast to existing computational PPDA primitives such as secure multiparty computation and data randomization based approaches, the proposed primitive `anonymous gossiping' is a communication primitive for privacy preserving personalized information aggregation complementing such traditional computational analytics. We realize this novel primitive by composing existing gossiping mechanisms for peer sampling & information aggregation and onion routing technique for establishing anonymous communication. This is more an `ideas' paper, rather than providing concrete and quantified results.

  6. 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.

  7. 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.

  8. The Effect of Computer-Mediated Communication on Anonymous End-of-Course Teaching Evaluations

    Science.gov (United States)

    Rhea, Nancy; Rovai, Alfred; Ponton, Michael; Derrick, Gail; Davis, John

    2007-01-01

    The purpose of this study was to determine if the nature of student comments on anonymous end-of-course evaluations differed relative to course delivery medium. Comments evaluated were submitted by 202 graduate students enrolled in face-to-face (F2F) and online versions of research and statistics courses over a four-year period. Results suggested…

  9. Knowing me, knowing you : Anonymity effects on social identity processes within groups

    NARCIS (Netherlands)

    Lea, M; Spears, R; de Groot, D

    2001-01-01

    The Social Identity Model of Deindividuation Effects (SIDE) proposes that depersonalization of self and others is responsible for the effects of visual anonymity on group behavior The authors investigated these mediating processes by assessing the effects of group-based self-categorization and stere

  10. Extended K-Anonymity Model for Privacy Preserving on Micro Data

    Directory of Open Access Journals (Sweden)

    Masoud Rahimi

    2015-11-01

    Full Text Available Today, information collectors, particularly statistical organizations, are faced with two conflicting issues. On one hand, according to their natural responsibilities and the increasing demand for the collected data, they are committed to propagate the information more extensively and with higher quality and on the other hand, due to the public concern about the privacy of personal information and the legal responsibility of these organizations in protecting the private information of their users, they should guarantee that while providing all the information to the population, the privacy is reasonably preserved. This issue becomes more crucial when the datasets published by data mining methods are at risk of attribute and identity disclosure attacks. In order to overcome this problem, several approaches, called p-sensitive k-anonymity, p+-sensitive k-anonymity, and (p, α-sensitive k-anonymity, were proposed. The drawbacks of these methods include the inability to protect micro datasets against attribute disclosure and the high value of the distortion ratio. In order to eliminate these drawbacks, this paper proposes an algorithm that fully protects the propagated micro data against identity and attribute disclosure and significantly reduces the distortion ratio during the anonymity process.

  11. The Framework for Approximate Queries on Simulation Data

    Energy Technology Data Exchange (ETDEWEB)

    Abdulla, G; Baldwin, C; Critchlow, T; Kamimura, R; Lee, B; Musick, R; Snapp, R; Tang, N

    2001-09-27

    AQSim is a system intended to enable scientists to query and analyze a large volume of scientific simulation data. The system uses the state of the art in approximate query processing techniques to build a novel framework for progressive data analysis. These techniques are used to define a multi-resolution index, where each node contains multiple models of the data. The benefits of these models are two-fold: (1) they are compact representations, reconstructing only the information relevant to the analysis, and (2) the variety of models capture different aspects of the data which may be of interest to the user but are not readily apparent in their raw form. To be able to deal with the data interactively, AQSim allows the scientist to make an informed tradeoff between query response accuracy and time. In this paper, we present the framework of AQSim with a focus on its architectural design. We also show the results from an initial proof-of-concept prototype developed at LLNL. The presented framework is generic enough to handle more than just simulation data.

  12. An Anonymity Revocation Technology for Anonymous Communication

    Science.gov (United States)

    Antoniou, Giannakis; Batten, Lynn; Parampalli, Udaya

    A number of privacy-enhancing technologies (PETs) have been proposed in the last three decades offering unconditional communication anonymity to their users. Unconditional anonymity can, however, be a security threat because it allows users to employ a PET in order to act maliciously while hiding their identity. In the last few years, several technologies which revoke the identity of users who use PETs have been proposed. These are known as anonymity revocation technologies (ARTs). However, the construction of ARTs has been developed in an ad hoc manner without a theoretical basis outlining the goals and underlying principles. In this chapter we present a set of fundamental principles and requirements for construction of an ART, identifying the necessary features. We then propose an abstract scheme for construction of an ART based on these features.

  13. Implementation of federated query processing on Linked Data

    OpenAIRE

    Zhou Y; S. De; Moessner K.

    2013-01-01

    As the number of Linked Data sets increases with more and more interconnections defined between them, querying a single data set is no longer enough for users who need data from mixed domains. The requirement to query data from different data sets motivates the research into federated queries. Network latency is one of the key factors which affect the performance of a federated query. The influence of network latency can be minimised by decreasing the number of remote requests, which is relat...

  14. ADQUEX: Adaptive Processing of Federated Queries over Linked Data based on Tuple Routing

    OpenAIRE

    Beiranvand, Amin; Ghadiri, Nasser

    2015-01-01

    Due to the distribution of linked data across the web, the methods that process federated queries through a distributed approach are more attractive to the users and have gained more prosperity. In distributed processing of federated queries, we need methods and procedures to execute the query in an optimal manner. Most of the existing methods perform the optimization task based on some statistical information, whereas the query processor does not have precise statistical information about th...

  15. Multiple Query Evaluation Based on an Enhanced Genetic Algorithm.

    Science.gov (United States)

    Tamine, Lynda; Chrisment, Claude; Boughanem, Mohand

    2003-01-01

    Explains the use of genetic algorithms to combine results from multiple query evaluations to improve relevance in information retrieval. Discusses niching techniques, relevance feedback techniques, and evolution heuristics, and compares retrieval results obtained by both genetic multiple query evaluation and classical single query evaluation…

  16. 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...

  17. De-anonymizing BitTorrent Users on Tor

    OpenAIRE

    Le Blond, Stevens; Manils, Pere; Chaabane, Abdelberi; Kaafar, Mohamed Ali; Legout, Arnaud; Castellucia, Claude; Dabbous, Walid

    2010-01-01

    Some BitTorrent users are running BitTorrent on top of Tor to preserve their privacy. In this extended abstract, we discuss three different attacks to reveal the IP address of BitTorrent users on top of Tor. In addition, we exploit the multiplexing of streams from different applications into the same circuit to link non-BitTorrent applications to revealed IP addresses.

  18. The Impact of Alcoholics Anonymous on other substance abuse related Twelve Step programs

    OpenAIRE

    Laudet, Alexandre B.

    2008-01-01

    This chapter explores the influence of the AA model on self-help fellowships addressing problems of drug dependence. Fellowships that have adapted the 12-step recovery model to other substances of abuse are reviewed; next similarities and differences between AA and drug-recovery 12-step organizations are examined; finally, we present empirical findings on patterns of attendance and perceptions of AA and Narcotics Anonymous (NA) among polydrug dependent populations, many of whom are cross-addi...

  19. Design on PKI-Based Anonymous Mobile Agent Security in E-Commerce

    Institute of Scientific and Technical Information of China (English)

    MENG Xiangsong; HAN Fengwu

    2006-01-01

    The security of mobile agent directly decides its usage width in e-commerce. Especially, to protect users' private information is becoming more important now and future. So an anonymous mobile agent security mechanism with the secure authentication infrastructure based on PKI(public key infrastructure) is proposed in the paper. The multi-agent system is programmed by java language and every agent must register itself in CA(certificate authority) before working in the net and express his legit identity which is temptly produced and used only once. The CA ensures the legal of all agents' identity which take part in communicaiton or trade. And every user agent identity only is used once which makes other agents cannot decipher users' private information. The security mechanism of the multi-agent system implements anonymity, integrity, data confidentiality of mobile agent based on the MH(multiple hop) integrity protection regard to PKI limit.

  20. 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.

  1. Group Anonymity

    CERN Document Server

    Chertov, Oleg; 10.1007/978-3-642-14058-7_61

    2010-01-01

    In recent years the amount of digital data in the world has risen immensely. But, the more information exists, the greater is the possibility of its unwanted disclosure. Thus, the data privacy protection has become a pressing problem of the present time. The task of individual privacy-preserving is being thoroughly studied nowadays. At the same time, the problem of statistical disclosure control for collective (or group) data is still open. In this paper we propose an effective and relatively simple (wavelet-based) way to provide group anonymity in collective data. We also provide a real-life example to illustrate the method.

  2. Web Database Query Interface Annotation Based on User Collaboration

    Institute of Scientific and Technical Information of China (English)

    LIU Wei; LIN Can; MENG Xiaofeng

    2006-01-01

    A vision based query interface annotation method is used to relate attributes and form elements in form-based web query interfaces, this method can reach accuracy of 82%.And a user participation method is used to tune the result; user can answer "yes" or "no" for existing annotations, or manually annotate form elements.Mass feedback is added to the annotation algorithm to produce more accurate result.By this approach, query interface annotation can reach a perfect accuracy.

  3. Wild Card Queries for Searching Resources on the Web

    CERN Document Server

    Rafiei, Davood

    2009-01-01

    We propose a domain-independent framework for searching and retrieving facts and relationships within natural language text sources. In this framework, an extraction task over a text collection is expressed as a query that combines text fragments with wild cards, and the query result is a set of facts in the form of unary, binary and general $n$-ary tuples. A significance of our querying mechanism is that, despite being both simple and declarative, it can be applied to a wide range of extraction tasks. A problem in querying natural language text though is that a user-specified query may not retrieve enough exact matches. Unlike term queries which can be relaxed by removing some of the terms (as is done in search engines), removing terms from a wild card query without ruining its meaning is more challenging. Also, any query expansion has the potential to introduce false positives. In this paper, we address the problem of query expansion, and also analyze a few ranking alternatives to score the results and to r...

  4. On Enhancing Data Utility in K-Anonymization for Data without Hierarchical Taxonomies

    Directory of Open Access Journals (Sweden)

    Mohammad Rasool Sarrafi Aghdam

    2015-05-01

    Full Text Available K-anonymity is the model that is widely used to protect the privacy of individuals in publishing micro-data. It could be defined as clustering with constrain of minimum k tuples in each group. K-anonymity cuts down the linking confidence between sensitive information and specific individual by the ration of 1/k. However, the accuracy of the data in k-anonymous dataset decreases due to information loss. Moreover, most of the current approaches are for numerical attributes or in case of categorical attributes they require extra information such as attribute hierarchical taxonomies which often do not exist. In this paper we propose a new model, based on clustering, defining the distance between tuples including numerical and categorical attributes which does not require extra information and present the SpatialDistance (SD heuristic algorithm. Comparisons of experimental results on real datasets between SD algorithm and existing well-known algorithms show that SD performs the best and offers much higher data utility and reduces the information loss significantly.

  5. 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.

  6. 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. PMID:27442957

  7. 一种基于SPKI的匿名支付方案%An Anonymous Payment Scheme Based on SPKI

    Institute of Scientific and Technical Information of China (English)

    朱庆生; 李唯唯; 王茜; 傅鹤岗

    2003-01-01

    SPKI is a proposed standard for public-key certificates. One important property of SPKI is that SPKI is key-oriented rather than name-oriented, and the public-key is globally unique. In this paper we propose an anonymous paymentscheme based on SPKI aiming at the problem of anonymous payment in B2C e-commerce. In the scheme we use the key-oriented characteristic of SPKI to link the public key to the account, and use authorization certificates to pay. The scheme achieves the anonymity very well.

  8. 基于 SpaceTwist 的 k-匿名增量近邻查询位置隐私保护算法%SpaceTwist-based k-anonymity incremental nearest neighbor query algorithm for location privacy protection

    Institute of Scientific and Technical Information of China (English)

    胡德敏; 郑霞

    2016-01-01

    随着移动网络的持续进步,基于位置的服务在日常生活中被广泛应用,同时位置隐私保护也成为广大用户所关注的焦点。基于 SpaceTwist 和 k-匿名算法,结合路网环境提出一种新的位置隐私保护方法。该方法摆脱第三方可信匿名器,采用客户—服务器体系结构,根据用户的位置隐私需求结合用户所在路网环境设计出用户端匿名区生成算法,并且保证 k-匿名。用户端以该匿名区请求基于位置的服务,服务器根据用户请求返回检索点并满足用户期望的 K 近邻结果。根据不同的路网环境和用户隐私需求进行大量实验,证明该算法在满足用户基于位置服务需求的同时提高了对用户位置隐私的保护。%With continued advances in mobile Internet,the location-based services are widely used in daily life,more and more users focus on the location privacy protection.This paper proposed a new location privacy protection scheme which com-bined with the network environment and based on the SpaceTwist algorithm and k-anonymity algorithm.The approach prefered to client-server structure rather than trusted third party server and designed the anonymity algorithm in user end according to user’s request of location privacy and the network environment,which ensured the k-anonymity.The mobile end users could request the location-based services in its anonymous area,and the server would return the access points to meet user’s expect K-value.Finally,it evaluated the proposed approach by a large number of experiments according to different network environ-ment together with different users privacy needs.The results demonstrate this algorithm meets the user’s requests of location-based services and at the same time it improves the protection of user’s location privacy.

  9. Quantum private query based on single-photon interference

    Science.gov (United States)

    Xu, Sheng-Wei; Sun, Ying; Lin, Song

    2016-08-01

    Quantum private query (QPQ) has become a research hotspot recently. Specially, the quantum key distribution (QKD)-based QPQ attracts lots of attention because of its practicality. Various such kind of QPQ protocols have been proposed based on different technologies of quantum communications. Single-photon interference is one of such technologies, on which the famous QKD protocol GV95 is just based. In this paper, we propose two QPQ protocols based on single-photon interference. The first one is simpler and easier to realize, and the second one is loss tolerant and flexible, and more practical than the first one. Furthermore, we analyze both the user privacy and the database privacy in the proposed protocols.

  10. Anonymous online purchases with exhaustive operational security

    OpenAIRE

    Van Mieghem, Vincent; Pouwelse, Johan

    2015-01-01

    This paper describes the process of remaining anonymous online and its concurrent operational security that has to be performed. It focusses particularly on remaining anonymous while purchasing online goods, resulting in anonymously bought items. Different aspects of the operational security process as well as anonymously funding with cryptocurrencies are described. Eventually it is shown how to anonymously purchase items and services from the hidden web, as well as the delivery. It is shown ...

  11. Advice from a medical expert through the Internet on queries about AIDS and hepatitis: analysis of a pilot experiment.

    Directory of Open Access Journals (Sweden)

    Javier Marco

    2006-07-01

    Full Text Available BACKGROUND: Advice from a medical expert on concerns and queries expressed anonymously through the Internet by patients and later posted on the Web, offers a new type of patient-doctor relationship. The aim of the current study was to perform a descriptive analysis of questions about AIDS and hepatitis made to an infectious disease expert and sent through the Internet to a consumer-oriented Web site in the Spanish language. METHODS AND FINDINGS: Questions were e-mailed and the questions and answers were posted anonymously in the "expert-advice" section of a Web site focused on AIDS and hepatitis. We performed a descriptive study and a temporal analysis of the questions received in the first 12 months after the launch of the site. A total of 899 questions were received from December 2003 to November 2004, with a marked linear growth pattern. Questions originated in Spain in 68% of cases and 32% came from Latin America (the Caribbean, Central America, and South America. Eighty percent of the senders were male. Most of the questions concerned HIV infection (79% with many fewer on hepatitis (17%. The highest numbers of questions were submitted just after the weekend (37% of questions were made on Mondays and Tuesdays. Risk factors for contracting HIV infection were the most frequent concern (69%, followed by the window period for detection (12.6%, laboratory results (5.9%, symptoms (4.7%, diagnosis (2.7%, and treatment (2.2%. CONCLUSIONS: Our results confirm a great demand for this type of "ask-the-expert" Internet service, at least for AIDS and hepatitis. Factors such as anonymity, free access, and immediate answers have been key factors in its success.

  12. 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...... 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...

  13. Online Query Scheduling on Source Permutation for Big Data Integration

    OpenAIRE

    Yuan, Zimu; Guo, Shusheng

    2015-01-01

    Big data integration could involve a large number of sources with unpredictable redundancy information between them. The approach of building a central warehousing to integrate big data from all sources then becomes infeasible because of so large number of sources and continuous updates happening. A practical approach is to apply online query scheduling that inquires data from sources at runtime upon receiving a query. In this paper, we address the Time-Cost Minimization Problem for online qu...

  14. An arbitrated quantum signature scheme based on entanglement swapping with signer anonymity

    Science.gov (United States)

    Li, Wei; Fan, Ming-Yu; Wang, Guang-Wei

    2012-12-01

    In this paper an arbitrated quantum signature scheme based on entanglement swapping is proposed. In this scheme a message to be signed is coded with unitary operators. Combining quantum measurement with quantum encryption, the signer can generate the signature for a given message. Combining the entangled states generated by the TTP's Bell measurement with the signature information, the verifier can verify the authentication of a signature through a single quantum state measurement. Compared with previous schemes, our scheme is more efficient and less complex, furthermore, our scheme can ensure the anonymity of the signer.

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

    NARCIS (Netherlands)

    Kotoulas, S; Urbani, J.; Boncz, P.A.; Mika, P.

    2012-01-01

    We 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 high-value skew.

  16. Optimization Query Process of Mediators Interrogation Based On Combinatorial Storage

    Directory of Open Access Journals (Sweden)

    L. Cherrat

    2013-05-01

    Full Text Available In the distributed environment where a query involves several heterogeneous sources, communication costs must be taken into consideration. In this paper we describe a query optimization approach using dynamic programming technique for set integrated heterogeneous sources. The objective of the optimization is to minimize the total processing time including load processing, request rewriting and communication costs, to facilitate communication inter-sites and to optimize the time of data transfer from site to others. Moreover, the ability to store data in more than one centre site provides more flexibility in terms of Security/Safety and overload of the network. In contrast to optimizers which are considered a restricted search space, the proposed optimizer searches the closed subsets of sources and independency relationship which may be deep laniary or hierarchical trees. Especially the execution of the queries can start traversal anywhere over any subset and not only from a specific source.

  17. Efficient Queries of Stand-off Annotations for Natural Language Processing on Electronic Medical Records.

    Science.gov (United States)

    Luo, Yuan; Szolovits, Peter

    2016-01-01

    In natural language processing, stand-off annotation uses the starting and ending positions of an annotation to anchor it to the text and stores the annotation content separately from the text. We address the fundamental problem of efficiently storing stand-off annotations when applying natural language processing on narrative clinical notes in electronic medical records (EMRs) and efficiently retrieving such annotations that satisfy position constraints. Efficient storage and retrieval of stand-off annotations can facilitate tasks such as mapping unstructured text to electronic medical record ontologies. We first formulate this problem into the interval query problem, for which optimal query/update time is in general logarithm. We next perform a tight time complexity analysis on the basic interval tree query algorithm and show its nonoptimality when being applied to a collection of 13 query types from Allen's interval algebra. We then study two closely related state-of-the-art interval query algorithms, proposed query reformulations, and augmentations to the second algorithm. Our proposed algorithm achieves logarithmic time stabbing-max query time complexity and solves the stabbing-interval query tasks on all of Allen's relations in logarithmic time, attaining the theoretic lower bound. Updating time is kept logarithmic and the space requirement is kept linear at the same time. We also discuss interval management in external memory models and higher dimensions. PMID:27478379

  18. On containment of conjunctive queries with arithmetic comparisons

    OpenAIRE

    Afrati, F; Li, Chen; Mitra, P.

    2004-01-01

    We study the following problem: how to test if Q(2) is contained in Q(1), where Q(1) and Q(2) are conjunctive queries with arithmetic comparisons? This problem is fundamental in a large variety of database applications. Existing algorithms first normalize the queries, then test a logical implication using multiple containment mappings from Q(1) to Q(2). We are interested in cases where the containment can be tested more efficiently. This work aims to (a) reduce the problem complexity from Pi(...

  19. Study on Pear Diseases Query System Based on Ontology and SWRL

    OpenAIRE

    Sun, Qian; Liang, Yong

    2013-01-01

    International audience This paper studied the construction of Pear Diseases Domain Ontology (PDDO), and the realization of query system based on PDDO and SWRL. First, an approach to build PDDO based on SWRL was proposed, which consists of confirming core concepts, adding the properties of concepts and the relationships between concepts, adding the instances of concepts, representing domain ontology, adding SWRL rules and reasoning. Then the query system model and implementation algorithm w...

  20. Extracting Result Schema Based on Query Instances in the Deep Web

    Institute of Scientific and Technical Information of China (English)

    NIE Tiezheng; YU Ge; SHEN Derong; KOU Yue; LIU Wei

    2007-01-01

    Deep Web sources contain a large of high-quality and query-related structured date. One of the challenges in the Deep Web is extracting result schemas of Deep Web sources. To address this challenge, this paper describes a novel approach that extracts both result data and the result schema of a Web database.The approach first models the query interface of a Deep Web source and fills in it with a specifically query instance. Then the result pages of the Deep Web sources are formatted in the tree structure to retrieve subtrees that contain elements of the query instance. Next, result schema of the Deep Web source is extracted by matching the subtree' nodes with the query instance, in which,a two-phase schema extraction method is adopted for obtaining more accurate result schema. Finally, experiments on real Deep Web sources show the utility of our approach, which provides a high precision and recall.

  1. 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.

  2. ANONYMIZATION BASED ON NESTED CLUSTERING FOR PRIVACY PRESERVATION IN DATA MINING

    Directory of Open Access Journals (Sweden)

    V.Rajalakshmi

    2013-07-01

    Full Text Available Privacy Preservation in data mining protects the data from revealing unauthorized extraction of information. Data Anonymization techniques implement this by modifying the data, so that the original values cannot be acquired easily. Perturbation techniques are variedly used which will greatly affect the quality of data,since there is a trade-off between privacy preservation and information loss which will subsequently affect the result of data mining. The method that is proposed in this paper is based on nested clustering of data andperturbation on each cluster. The size of clusters is kept optimal to reduce the information loss. The paper explains the methodology, implementation and results of nested clustering. Various metrics are also provided to explicate that this method overcomes the disadvantages of other perturbation methods.

  3. QUERY TRANSLATION USING CONCEPTS SIMILARITY BASED ON QURAN ONTOLOGY FOR CROSS-LANGUAGE INFORMATION RETRIEVAL

    Directory of Open Access Journals (Sweden)

    Zulaini Yahya

    2013-01-01

    Full Text Available In Cross-Language Information Retrieval (CLIR process, the translation effects have a direct impact on the accuracy of follow-up retrieval results. In dictionary-based approach, we are dealing with the words that have more than one meaning which can decrease the retrieval performance if the query translation return an incorrect translations. These issues need to be overcome using efficient technique. In this study we proposed a Cross-Language Information Retrieval (CLIR method based on domain ontology using Quran concepts for disambiguating translation of the query and to improve the dictionary-based query translation. For experimentation, we use Quran ontology written in English and Malay languages as a bilingual parallel-corpora and Quran concepts as a resource for cross-language query translation along with dictionary-based translation. For evaluation, we measure the performance of three IR systems. IR1 is natural language query IR, IR2 is natural language query CLIR based on dictionary (as a Baseline and IR3 is the retrieval of this research proposed method using Mean Average Precision (MAP and average precision at 11 points of recall. The experimental result shows that our proposed method brings significant improvement in retrieval accuracy for English document collections, but deficient for Malay document collections. The proposed CLIR method can obtain query expansion effect and improve retrieval performance in certain language.

  4. Relative expressive power of navigational querying on graphs

    OpenAIRE

    Fletcher, GHL George; Gyssens, M; Leinders, D; Surinx, D; Van den Bussche, J; Van Gucht, D; Vansummeren, S; Wu, Y

    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; and the diversity relation. All these operators map binary relations to binary relations. We compare the expressive power of al...

  5. Relative expressive power of navigational querying on graphs

    OpenAIRE

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

    2011-01-01

    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 di erence; projection; coprojection; converse; transitive closure; and the diversity relation. All these operators map binary relations to binary relat...

  6. Loading and Querying Data on Distributed Virtualized Web Application Servers

    OpenAIRE

    Mack, Moritz

    2009-01-01

    Virtualized web application servers within computational clouds, such as the GoogleApp Engine, generally restrict resource usage and therefore provide limited,relationally none-complete query facilities only. This work investigates how scalable,reliable and a more powerful access to the App Engine Datastore can beaccomplished and an Optimized Distributed Datastore Exchange (ODDSE) ispresented. Being aware of the App Engine’s resource restrictions ODDSE provides areliable and failure safe quer...

  7. 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

  8. Efficient Anonymizations with Enhanced Utility

    Directory of Open Access Journals (Sweden)

    Jacob Goldberger

    2010-08-01

    Full Text Available One of the most well studied models of privacy preservation is k-anonymity. Previous studies of k-anonymization used various utility measures that aim at enhancing the correlation between the original public data and the generalized public data. We, bearing in mind that a primary goal in releasing the anonymized database for datamining is to deducemethods of predicting the private data from the public data, propose a new information-theoretic measure that aims at enhancing the correlation between the generalized public data and the private data. Such a measure significantly enhances the utility of the released anonymized database for data mining. We then proceed to describe a new algorithm that is designed to achieve k-anonymity with high utility, independently of the underlying utility measure. That algorithm is based on a modified version of sequential clustering which is the method of choice in clustering. Experimental comparison with four well known algorithms of k-anonymity show that the sequential clustering algorithm is an efficient algorithm that achieves the best utility results. We also describe a modification of the algorithm that outputs k-anonymizations which respect the additional security measure of l-diversity.

  9. Lower Bounds on Quantum Query Complexity for Read-Once Formulas with XOR and MUX Operators

    Science.gov (United States)

    Fukuhara, Hideaki; Takimoto, Eiji

    We introduce a complexity measure r for the class F of read-once formulas over the basis {AND, OR, NOT, XOR, MUX} and show that for any Boolean formula F in the class F, r(F) is a lower bound on the quantum query complexity of the Boolean function that F represents. We also show that for any Boolean function f represented by a formula in F, the deterministic query complexity of f is only quadratically larger than the quantum query complexity of f. Thus, the paper gives further evidence for the conjecture that there is an only quadratic gap for all functions.

  10. 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.

  11. Supporting K nearest neighbors query on high-dimensional data in P2P systems

    Institute of Scientific and Technical Information of China (English)

    Mei LI; Wang-Chien LEE; Anand SIVASUBRAMANIAM; Jizhong ZHAO

    2008-01-01

    Peer-to-peer systems have been widely used for sharing and exchanging data and resources among numerous computer nodes.Various data objects identifiable with high dimensional feature vectors,such as text,images,genome sequences,are starting to leverage P2P technology.Most of the existing works have been focusing on queries on data objects with one or few attributes and thus are not applicable on high dimensional data objects.In this study,we investigate K nearest neighbors query (KNN)on high dimensional data objects in P2P systems.Efficient query algorithm and solutions that address various technical challenges raised by high dimensionality,such as search space resolution and incremental search space refinement,are proposed.An extensive simulation using both synthetic and real data sets demonstrates that our proposal efficiently supports KNN query on high dimensional data in P2P systems.

  12. On the evaluation of fuzzy quantified queries in a database management system

    Science.gov (United States)

    Bosc, Patrick; Pivert, Olivier

    1992-01-01

    Many propositions to extend database management systems have been made in the last decade. Some of them aim at the support of a wider range of queries involving fuzzy predicates. Unfortunately, these queries are somewhat complex and the question of their efficiency is a subject under discussion. In this paper, we focus on a particular subset of queries, namely those using fuzzy quantified predicates. More precisely, we will consider the case where such predicates apply to individual elements as well as to sets of elements. Thanks to some interesting properties of alpha-cuts of fuzzy sets, we are able to show that the evaluation of these queries can be significantly improved with respect to a naive strategy based on exhaustive scans of sets or files.

  13. Narcotics Anonymous: Anonymity, admiration, and prestige in an egalitarian community

    OpenAIRE

    Snyder, Jeffrey K.; Fessler, Daniel M.T.

    2014-01-01

    Narcotics Anonymous (NA) supports long-term recovery for those addicted to drugs. Paralleling social dynamics in many small-scale societies, NA exhibits tension between egalitarianism and prestige-based hierarchy, a problem exacerbated by the addict’s personality as characterized by NA’s ethnopsychology.  We explore how NA’s central principle of anonymity normatively translates into egalitarianism among group members.  Turning to the lived reality of membership, building on Carr’s (2011) conc...

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

    OpenAIRE

    Svetlana A. Firsova; Elena A. Ryabukhina

    2016-01-01

    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...

  15. ZuiScat : querying and visualizing information spaces on personal digital assistants

    OpenAIRE

    Büring, Thorsten; Reiterer, Harald

    2005-01-01

    ZuiScat is a visualization concept for querying large information spaces on Personal Digital Assistants (PDA). Retrieval results are presented in a dynamic scatterplot, which is enhanced by geometric and semantic zoom techniques to provide smooth transitions from abstract visual encodings to data content. The same visualization is also used to manage bookmarks and to serve as a powerful query history tool. User feedback suggests that ZuiScat provides intuitive and efficient data access but st...

  16. On the Expressiveness of Implicit Provenance in Query and Update Languages

    OpenAIRE

    Buneman, Peter; Cheney, James; Vansummeren, Stijn

    2008-01-01

    Information describing the origin of data, generally referred to as provenance, is important in scientific and curated databases where it is the basis for the trust one puts in their contents. Since such databases are constructed using operations of both query and update languages, it is of paramount importance to describe the effect of these languages on provenance. In this article we study provenance for query and update languages that are closely related to SQL, and compare two ways in wh...

  17. QUERY EXPANSION OF LOCAL CO-OCCURRENCE BASED ON QUERY LOG%基于查询日志的局部共现查询扩展

    Institute of Scientific and Technical Information of China (English)

    丁晓渊; 顾春华; 王明永

    2013-01-01

    Query extension is a key issue in information retrieval , the efficiency of query expansion determines the retrieval performance of retrieval system .Most of the query expansions are based on global analysis or local analysis , though the accuracies have been greatly improved, but they all have their own limitations .Query log is the record of long term query behaviour by a great quantity of users .In this paper, we propose a query log-based expansion method of local co-occurrence, through which we can build an associated diagram of user initial query and user document through mining the link between user ’ s initial query and user logs , and construct the related word list using local co-occurrence method , thus to realise the query expansion .The test on 50, 000 corpora shows that the precision has about 44%improvement after using this method .%查询扩展是信息检索中的一个关键问题,查询扩展的有效性决定了检索系统的检索性能。大多数的查询扩展基于全局分析或者局部分析法,虽然准确率有了很大的提高,但是都有各自的局限性。查询日志是大量用户长期查询行为的记录。提出了基于查询日志的局部共现查询扩展方法,该方法通过挖掘用户初始查询与查询日志之间的联系,构建一个用户初始查询与用户文档的关联关系图,并且使用局部共现的方法构建相关词表,从而实现查询扩展。在50000篇语料上的测试表明,该方法相对于未扩展时准确率提高了44%以上。

  18. Visual graph query formulation and exploration: a new perspective on information retrieval at the edge

    Science.gov (United States)

    Kase, Sue E.; Vanni, Michelle; Knight, Joanne A.; Su, Yu; Yan, Xifeng

    2016-05-01

    Within operational environments decisions must be made quickly based on the information available. Identifying an appropriate knowledge base and accurately formulating a search query are critical tasks for decision-making effectiveness in dynamic situations. The spreading of graph data management tools to access large graph databases is a rapidly emerging research area of potential benefit to the intelligence community. A graph representation provides a natural way of modeling data in a wide variety of domains. Graph structures use nodes, edges, and properties to represent and store data. This research investigates the advantages of information search by graph query initiated by the analyst and interactively refined within the contextual dimensions of the answer space toward a solution. The paper introduces SLQ, a user-friendly graph querying system enabling the visual formulation of schemaless and structureless graph queries. SLQ is demonstrated with an intelligence analyst information search scenario focused on identifying individuals responsible for manufacturing a mosquito-hosted deadly virus. The scenario highlights the interactive construction of graph queries without prior training in complex query languages or graph databases, intuitive navigation through the problem space, and visualization of results in graphical format.

  19. Determination of the Internet Anonymity Influence on the Level of Aggression and Usage of Obscene Lexis

    OpenAIRE

    Potapova, Rodmonga; Gordeev, Denis

    2015-01-01

    This article deals with the analysis of the semantic content of the anonymous Russian-speaking forum 2ch.hk, different verbal means of expressing of the emotional state of aggression are revealed for this site, and aggression is classified by its directions. The lexis of different Russian-and English- speaking anonymous forums (2ch.hk and iichan.hk, 4chan.org) and public community "MDK" of the Russian-speaking social network VK is analyzed and compared with the Open Corpus of the Russian lang...

  20. 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.

  1. 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

  2. Navigational Query Languages

    OpenAIRE

    Surinx, Dimitri

    2013-01-01

    In this thesis we introduce navigational query languages on graphs. Path queries in our languages are built over several operators: identity, union, composition, projection, coprojection, converse, transitive closure, diversity, intersection and difference. The smallest language we will consider only contains the first 3 operators, while the largest language contains all operators. For these query languages we will characterize their complete relative expressive power, i.e., we will compare t...

  3. THESAURUS AND QUERY EXPANSION

    Directory of Open Access Journals (Sweden)

    Hazra Imran

    2009-11-01

    Full Text Available The explosive growth of the World Wide Web is making it difficult for a user to locate information that isrelevant to his/her interest. Though existing search engines work well to a certain extent but they still faceproblems like word mismatch which arises because the majority of information retrieval systemscompare query and document terms on lexical level rather than on semantic level and short query: theaverage length of queries by the user is less than two words. Short queries and the incompatibilitybetween the terms in user queries and documents strongly affect the retrieval of relevant document.Query expansion has long been suggested as a technique to increase the effectiveness of the informationretrieval. Query expansion is the process of supplementing additional terms or phrases to the originalquery to improve the retrieval performance. The central problem of query expansion is the selection ofthe expansion terms based on which user’s original query is expanded. Thesaurus helps to solve thisproblem. Thesaurus have frequently been incorporated in information retrieval system for identifying thesynonymous expressions and linguistic entities that are semantically similar. Thesaurus has been widelyused in many applications, including information retrieval and natural language processing.

  4. 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.

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

    Science.gov (United States)

    Sadesh, S; Suganthe, R C

    2015-01-01

    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. PMID:26221626

  6. Fully Dynamic Data Structure for Top-k Queries on Uncertain Data

    CERN Document Server

    Patil, Manish; Thankachan, Sharma V

    2010-01-01

    Top-$k$ queries allow end-users to focus on the most important (top-$k$) answers amongst those which satisfy the query. In traditional databases, a user defined score function assigns a score value to each tuple and a top-$k$ query returns $k$ tuples with the highest score. In uncertain database, top-$k$ answer depends not only on the scores but also on the membership probabilities of tuples. Several top-$k$ definitions covering different aspects of score-probability interplay have been proposed in recent past~\\cite{R10,R4,R2,R8}. Most of the existing work in this research field is focused on developing efficient algorithms for answering top-$k$ queries on static uncertain data. Any change (insertion, deletion of a tuple or change in membership probability, score of a tuple) in underlying data forces re-computation of query answers. Such re-computations are not practical considering the dynamic nature of data in many applications. In this paper, we propose a fully dynamic data structure that uses ranking func...

  7. PRESY: A Context Based Query Reformulation Tool for Information Retrieval on the Web

    CERN Document Server

    Bouramoul, Abdelkrim; Doan, Bich-Lien; 10.3844/jcssp.2010.470.477

    2011-01-01

    Problem Statement: The huge number of information on the web as well as the growth of new inexperienced users creates new challenges for information retrieval. It has become increasingly difficult for these users to find relevant documents that satisfy their individual needs. Certainly the current search engines (such as Google, Bing and Yahoo) offer an efficient way to browse the web content. However, the result quality is highly based on uses queries which need to be more precise to find relevant documents. This task still complicated for the majority of inept users who cannot express their needs with significant words in the query. For that reason, we believe that a reformulation of the initial user's query can be a good alternative to improve the information selectivity. This study proposes a novel approach and presents a prototype system called PRESY (Profile-based REformulation SYstem) for information retrieval on the web. Approach: It uses an incremental approach to categorize users by constructing a c...

  8. A Secure Anonymous Internet Electronic Voting Scheme Based on the Polynomial

    Institute of Scientific and Technical Information of China (English)

    CAO Feng; CAO Zhenfu

    2006-01-01

    In this paper, we use the polynomial function and Chaum's RSA (Rivest, Shamir, Adleman) blind signature scheme to construct a secure anonymous internet electronic voting scheme. In our scheme, each vote does not need to be revealed in the tallying phase. The ballot number of each candidate gets is counted by computing the degrees of two polynomials' greatest common divisor. Our scheme does not require a special voting channel and communication can occur entirely over the current internet.

  9. A Review on anonymization approach to preserve privacy of Published data through record elimination

    Directory of Open Access Journals (Sweden)

    Isha K. Gayki

    2013-11-01

    Full Text Available Data mining is the process of analyzing data. Data Privacy is collection of data and dissemination of data. Privacy issues arise in different area such as health care, intellectual property, biological data, financial transaction etc. It is very difficult to protect the data when there is transfer of data. Sensitive information must be protected. There are two kinds of major attacks against privacy namely record linkage and attribute linkage attacks. Research have proposed some methods namely k-anonymity, ℓ-diversity, t-closeness for data privacy. K-anonymity method preserves the privacy against record linkage attack alone. It is unable to prevent address attribute linkage attack. ℓ-diversity method overcomes the drawback of k-anonymity method. But it fails to prevent identity disclosure attack and attribute disclosure attack. t-closeness method preserves the privacy against attribute linkage attack but not identity disclosure attack. A proposed method used to preserve the privacy of individuals sensitive data from record and attribute linkage attacks. In the proposed method, privacy preservation is achieved through generalization by setting range values and through record elimination. A proposed method overcomes the drawback of both record linkage attack and attribute linkage attack.

  10. Shortest Path and Distance Queries on Road Networks: An Experimental Evaluation

    CERN Document Server

    Wu, Lingkun; Deng, Dingxiong; Cong, Gao; Zhu, Andy Diwen; Zhou, Shuigeng

    2012-01-01

    Computing the shortest path between two given locations in a road network is an important problem that finds applications in various map services and commercial navigation products. The state-of-the-art solutions for the problem can be divided into two categories: spatial-coherence-based methods and vertex-importance-based approaches. The two categories of techniques, however, have not been compared systematically under the same experimental framework, as they were developed from two independent lines of research that do not refer to each other. This renders it difficult for a practitioner to decide which technique should be adopted for a specific application. Furthermore, the experimental evaluation of the existing techniques, as presented in previous work, falls short in several aspects. Some methods were tested only on small road networks with up to one hundred thousand vertices; some approaches were evaluated using distance queries (instead of shortest path queries), namely, queries that ask only for the ...

  11. 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 propo

  12. PRESY: A Context Based Query Reformulation Tool for Information Retrieval on the Web

    Directory of Open Access Journals (Sweden)

    Abdelkrim Bouramoul

    2010-01-01

    Full Text Available Problem statement: The huge number of information on the web as well as the growth of new inexperienced users creates new challenges for information retrieval. It has become increasingly difficult for these users to find relevant documents that satisfy their individual needs. Certainly the current search engines (such as Google, Bing and Yahoo offer an efficient way to browse the web content. However, the result quality is highly based on uses queries which need to be more precise to find relevant documents. This task still complicated for the majority of inept users who cannot express their needs with significant words in the query. For that reason, we believe that a reformulation of the initial user's query can be a good alternative to improve the information selectivity. This study proposed a novel approach and presents a prototype system called Profile-based Reformulation System (PRESY for information retrieval on the web. Approach: It used an incremental approach to categorize users by constructing a contextual base. The latter was composed of two types of context (static and dynamic obtained using the users' profiles. The architecture proposed was implemented using .Net environment to perform queries reformulating tests. Results: The experiments gave at the end of this article show that the precision of the returned content is effectively improved. The tests were performed with the most popular searching engine (i.e., Google, Bind and Yahoo selected in particular for their high selectivity. Among the given results, we found that query reformulation improve the first three results by 10.7 and 11.7% of the next seven returned elements. So as we could see the reformulation of users' initial queries improves the pertinence of returned content. Conclusion/Recommendations: Therefore, we believed that the exploitation of contextual data based on users' profiles could be a very good way to reformulate user query. This complementary mechanism would

  13. Privacy Preserving Quantum Anonymous Transmission via Entanglement Relay

    OpenAIRE

    Wei Yang; Liusheng Huang; Fang Song

    2016-01-01

    Anonymous transmission is an interesting and crucial issue in computer communication area, which plays a supplementary role to data privacy. In this paper, we put forward a privacy preserving quantum anonymous transmission protocol based on entanglement relay, which constructs anonymous entanglement from EPR pairs instead of multi-particle entangled state, e.g. GHZ state. Our protocol achieves both sender anonymity and receiver anonymity against an active adversary and tolerates any number of...

  14. Anonymity and Historical-Anonymity in Location-Based Services

    Science.gov (United States)

    Bettini, Claudio; Mascetti, Sergio; Wang, X. Sean; Freni, Dario; Jajodia, Sushil

    The problem of protecting user’s privacy in Location-Based Services (LBS) has been extensively studied recently and several defense techniques have been proposed. In this contribution, we first present a categorization of privacy attacks and related defenses. Then, we consider the class of defense techniques that aim at providing privacy through anonymity and in particular algorithms achieving “historical k- anonymity” in the case of the adversary obtaining a trace of requests recognized as being issued by the same (anonymous) user. Finally, we investigate the issues involved in the experimental evaluation of anonymity based defense techniques; we show that user movement simulations based on mostly random movements can lead to overestimate the privacy protection in some cases and to overprotective techniques in other cases. The above results are obtained by comparison to a more realistic simulation with an agent-based simulator, considering a specific deployment scenario.

  15. 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

  16. Query auto completion in information retrieval

    NARCIS (Netherlands)

    Fei Cai

    2016-01-01

    Query auto completion is an important feature embedded into today's search engines. It can help users formulate queries which other people have searched for when he/she finishes typing the query prefix. Today's most sophisticated query auto completion approaches are based on the collected query logs

  17. 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...

  18. 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.

  19. 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...... (such as cat videos on YouTube or funny memes on 9GAG). Then Lea provides Joe with a short key k which, when applied to the entire website, recovers the document while hiding the identity of Lea among the large number of users of the website. Our contributions include: { Introducing and formally dening...

  20. 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...... (such as cat videos on YouTube or funny memes on 9GAG). Then Lea provides Joe with a short key $k$ which, when applied to the entire website, recovers the document while hiding the identity of Lea among the large number of users of the website. Our contributions include: - Introducing and formally...

  1. 一种基于XML小枝查询片段松弛的近似查询与结果排序方法%Approximate Query and Results Ranking Approach Based on XML Twig Query Fragment Relaxation

    Institute of Scientific and Technical Information of China (English)

    魏珂; 任建华; 孟祥福

    2012-01-01

    Based on XML twig query fragments relaxation, this paper proposed an approximate querying and results ranking approach to achieve the approximate query results against XML documents: our method gathers the query history to speculate the user's preferences, which is used to calculate the importance for each query fragment of the twig query,and relax the original query according to the sequence of the fragments' importance; based on the number of query fragments we adopt different relax way:if the number>2,relax the original query according to the granularity of the fragment; if the number<2, relax the original query according to the granularity of query node, and adopt a different way to relax the numerical query and non-numerical query,and then obtain the most relevant query results. Finally, the relevant query results are ranked based on their satisfaction degree to the original query and the user preferences. Our experiment shows that the approximate querying and the results ranking approach can efficiently meet the user's needs and user's preferences,has the high recall and precision.%提出了一种基于XML小枝查询片段松弛的近似查询与结果排序方法来实现用户在XML文档中的近似查询:通过收集用户的查询历史来推测用户偏好,并以此计算原始小枝查询分解得到的查询片段的重要程度,然后按照重要程度的排序进行查询松弛;在松弛方法中,根据查询片段数目的不同采用不同的松弛方法,若片段数目较多则以查询片段为粒度对其松弛,较少则以查询结点为粒度对数值查询与非数值查询采用不同的方法进行松弛,得到最为相关的近似查询结果;最后接近似查询结果对原始查询和用户偏好的满足程度进行排序并输出.实验证明,该近似查询方法能够较好地满足用户的需求和偏好,具有较高的查全率和准确率.

  2. A Semantic Query Transformation Approach Based on Ontology for Search Engine

    Directory of Open Access Journals (Sweden)

    SAJENDRA KUMAR

    2012-05-01

    Full Text Available These days we are using some popular web search engines for information retrieval in all areas, such engine are as Google, Yahoo!, and Live Search, etc. to obtain initial helpful information.Which information we retrieved via search engine may not be relevant to the search target in the search engine user's mind. When user not found relevant information he has to shortlist the results. Thesesearch engines use traditional search service based on "static keywords", which require the users to type in the exact keywords. This approach clearly puts the users in a critical situation of guessing the exact keyword. The users may want to define their search by using attributes of the search target. But the relevancy of results in most cases may not be satisfactory and the users may not be patient enough to browse through complete list of pages to get a relevant result. The reason behind this is the search engines performs search based on the syntax not on semantics. But they seemed to be less efficient to understand the relationship between the keywords which had an adverse effect on the results it produced. Semantic search engines – only solution to this; which returns concepts not documents according to user query matching. In This paper we proposed a semantic query interface which creates a semantic query according the user input query and study of current semantic search engine techniques for semantic search.

  3. On-Line Logging In of Periodicals by CODEN Using Interactive Query Report Processor

    Science.gov (United States)

    Allen, Albert H.; Beirne, Eugene F.

    1976-01-01

    Journal Log In is a computer on-line system for checking in periodicals. Used in conjunction with an IBM system called IQRP (Interactive Query Report Processing), it permits a serials librarian to use shortened commands coupled with a CODEN for ease in logging in periodicals. (Author)

  4. Algebraic Optimization of Outerjoin Queries

    OpenAIRE

    Galindo-Legaria, Cesar Alejandro

    1992-01-01

    An advantage of relational database languages is that they allow "declarative" query specification: users pose queries as a set of conditions or properties on data to be retrieved, rather than by giving a procedure to obtain such data. The database system is then responsible for generating an efficient execution plan, depending on how information is physically stored. In this context, generation of efficient plans is known as database query optimization. Careful query analysis is justified du...

  5. Lower Bounds on Query Complexity for Testing Bounded-Degree CSPs

    CERN Document Server

    Yoshida, Yuichi

    2010-01-01

    In this paper, we consider lower bounds on the query complexity for testing CSPs in the bounded-degree model. First, for any ``symmetric'' predicate $P:{0,1}^{k} \\to {0,1}$ except \\equ where $k\\geq 3$, we show that every (randomized) algorithm that distinguishes satisfiable instances of CSP(P) from instances $(|P^{-1}(0)|/2^k-\\epsilon)$-far from satisfiability requires $\\Omega(n^{1/2+\\delta})$ queries where $n$ is the number of variables and $\\delta>0$ is a constant that depends on $P$ and $\\epsilon$. This breaks a natural lower bound $\\Omega(n^{1/2})$, which is obtained by the birthday paradox. We also show that every one-sided error tester requires $\\Omega(n)$ queries for such $P$. These results are hereditary in the sense that the same results hold for any predicate $Q$ such that $P^{-1}(1) \\subseteq Q^{-1}(1)$. For EQU, we give a one-sided error tester whose query complexity is $\\tilde{O}(n^{1/2})$. Also, for 2-XOR (or, equivalently E2LIN2), we show an $\\Omega(n^{1/2+\\delta})$ lower bound for distinguishi...

  6. Declarative Visualization Queries

    Science.gov (United States)

    Pinheiro da Silva, P.; Del Rio, N.; Leptoukh, G. G.

    2011-12-01

    In an ideal interaction with machines, scientists may prefer to write declarative queries saying "what" they want from a machine than to write code stating "how" the machine is going to address the user request. For example, in relational database, users have long relied on specifying queries using Structured Query Language (SQL), a declarative language to request data results from a database management system. In the context of visualizations, we see that users are still writing code based on complex visualization toolkit APIs. With the goal of improving the scientists' experience of using visualization technology, we have applied this query-answering pattern to a visualization setting, where scientists specify what visualizations they want generated using a declarative SQL-like notation. A knowledge enhanced management system ingests the query and knows the following: (1) know how to translate the query into visualization pipelines; and (2) how to execute the visualization pipelines to generate the requested visualization. We define visualization queries as declarative requests for visualizations specified in an SQL like language. Visualization queries specify what category of visualization to generate (e.g., volumes, contours, surfaces) as well as associated display attributes (e.g., color and opacity), without any regards for implementation, thus allowing scientists to remain partially unaware of a wide range of visualization toolkit (e.g., Generic Mapping Tools and Visualization Toolkit) specific implementation details. Implementation details are only a concern for our knowledge-based visualization management system, which uses both the information specified in the query and knowledge about visualization toolkit functions to construct visualization pipelines. Knowledge about the use of visualization toolkits includes what data formats the toolkit operates on, what formats they output, and what views they can generate. Visualization knowledge, which is not

  7. Query Performance Prediction for Information Retrieval Based on Covering Topic Score

    Institute of Scientific and Technical Information of China (English)

    Hao Lang; Bin Wang; Gareth Jones; Jin-Tao Li; Fan Ding; Yi-Xuan Liu

    2008-01-01

    We present a statistical method called Covering Topic Score (CTS) to predict query performance for information retrieval. Estimation is based on how well the topic of a user's query is covered by documents retrieved from a certain retrieval system. Our approach is conceptually simple and intuitive, and can be easily extended to incorporate features beyond bag-of-words such as phrases and proximity of terms. Experiments demonstrate that CTS significantly correlates with query performance in a variety of TREC test collections, and in particular CTS gains more prediction power benefiting from features of phrases and proximity of terms. We compare CTS with previous state-of-the-art methods for query performance prediction including clarity score and robustness score. Our experimental results show that CTS consistently performs better than, or at least as well as, these other methods. In addition to its high effectiveness, CTS is also shown to have very low computational complexity, meaning that it can be practical for real applications.

  8. Anonymity in science.

    Science.gov (United States)

    Neuroskeptic

    2013-05-01

    The history of science is replete with important works that were originally published without the author's legal name being revealed. Most modern scientists will have worked anonymously in their capacity as peer reviewers. But why is anonymity so popular? And is it a valid approach? I argue that pseudonymity and anonymity, although not appropriate for all forms of scientific communication, have a vital role to play in academic discourse. They can facilitate the free expression of interpretations and ideas, and can help to ensure that suggestions and criticisms are evaluated dispassionately, regardless of their source. PMID:23570959

  9. 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.

  10. Movement Data Anonymity through Generalization

    Directory of Open Access Journals (Sweden)

    Anna Monreale

    2010-08-01

    Full Text Available Wireless networks and mobile devices, such as mobile phones and GPS receivers, sense and track the movements of people and vehicles, producing society-wide mobility databases. This is a challenging scenario for data analysis and mining. On the one hand, exciting opportunities arise out of discovering new knowledge about human mobile behavior, and thus fuel intelligent info-mobility applications. On other hand, new privacy concerns arise when mobility data are published. The risk is particularly high for GPS trajectories, which represent movement of a very high precision and spatio-temporal resolution: the de-identification of such trajectories (i.e., forgetting the ID of their associated owners is only a weak protection, as generally it is possible to re-identify a person by observing her routine movements. In this paper we propose a method for achieving true anonymity in a dataset of published trajectories, by defining a transformation of the original GPS trajectories based on spatial generalization and k-anonymity. The proposed method offers a formal data protection safeguard, quantified as a theoretical upper bound to the probability of re-identification. We conduct a thorough study on a real-life GPS trajectory dataset, and provide strong empirical evidence that the proposed anonymity techniques achieve the conflicting goals of data utility and data privacy. In practice, the achieved anonymity protection is much stronger than the theoretical worst case, while the quality of the cluster analysis on the trajectory data is preserved.

  11. 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.

  12. Optimal query error of quantum approximation on some Sobolev classes

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    We study the approximation of the imbedding of functions from anisotropic and general-ized Sobolev classes into Lq([0,1]d) space in the quantum model of computation. Based on the quantum algorithms for approximation of finite imbedding from LpN to LNq , we develop quantum algorithms for approximating the imbedding from anisotropic Sobolev classes B(Wpr ([0,1]d)) to Lq([0,1]d) space for all 1 q,p ∞ and prove their optimality. Our results show that for p < q the quantum model of computation can bring a speedup roughly up to a squaring of the rate in the classical deterministic and randomized settings.

  13. MHBase: A Distributed Real-Time Query Scheme for Meteorological Data Based on HBase

    Directory of Open Access Journals (Sweden)

    Tinghuai Ma

    2016-03-01

    Full Text Available Meteorological technology has evolved rapidly in recent years to provide enormous, accurate and personalized advantages in the public service. Large volumes of observational data are generated gradually by technologies such as geographical remote sensing, meteorological radar satellite, etc. that makes data analysis in weather forecasting more precise but also poses a threat to the traditional method of data storage. In this paper, we present MHBase, (Meteorological data based on HBase (Hadoop Database, a distributed real-time query scheme for meteorological data based on HBase. The calibrated data obtained from terminal devices will be partitioned into HBase and persisted to HDFS (the Hadoop Distributed File System. We propose two algorithms (the Indexed Store and the Indexed Retrieve Algorithms to implement a secondary index using HBase Coprocessors, which allow MHbase to provide high performance data querying on columns other than rowkey. Experimental results show that the performance of MHBase can satisfy the basic demands of meteorological business services.

  14. Bayesian Query-Focused Summarization

    CERN Document Server

    Daumé, Hal

    2009-01-01

    We present BayeSum (for ``Bayesian summarization''), a model for sentence extraction in query-focused summarization. BayeSum leverages the common case in which multiple documents are relevant to a single query. Using these documents as reinforcement for query terms, BayeSum is not afflicted by the paucity of information in short queries. We show that approximate inference in BayeSum is possible on large data sets and results in a state-of-the-art summarization system. Furthermore, we show how BayeSum can be understood as a justified query expansion technique in the language modeling for IR framework.

  15. Towards a Theory of Anonymous Networking

    CERN Document Server

    Ghaderi, J

    2009-01-01

    The problem of anonymous networking when an eavesdropper observes packet timings in a communication network is considered. The goal is to hide the identities of source-destination nodes, and paths of information flow in the network. One way to achieve such an anonymity is to use mixers. Mixers are nodes that receive packets from multiple sources and change the timing of packets, by mixing packets at the output links, to prevent the eavesdropper from finding sources of outgoing packets. In this paper, we consider two simple but fundamental scenarios: double input-single output mixer and double input-double output mixer. For the first case, we use the information-theoretic definition of the anonymity, based on average entropy per packet, and find an optimal mixing strategy under a strict latency constraint. For the second case, perfect anonymity is considered, and a maximal throughput strategy with perfect anonymity is found that minimizes the average delay.

  16. 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

    2016-01-01

    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. PMID:27537890

  17. 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

    2016-01-01

    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. PMID:27537890

  18. 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

    2016-01-01

    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.

  19. QUERY TUNING IN ORACLE DATABASE

    Directory of Open Access Journals (Sweden)

    Kamsuriah Ahmad

    2012-01-01

    Full Text Available Oracle database is well suited to use for managing and exchanging of corporate data, especially for companies that have large-scale databases. Even though Oracle can work best, however, there are conditions where Oracle does not perform well and consume more time to perform the query transaction. This is when the database tuning process is needed. This process will solve the problems of low performance and high execution time when accessing data in the database. This study aims to propose an improvement process of query tuning that can reduce queries execution time. The cause of the problems can be discovered by reviewing the source code, List of Value (LOV and view on the current system. To enhance the query, existing query scripts need to be modified to fit the tuning process. As an evaluation on the effectiveness of the proposed query tuning process, a comparison of study is done. The result of the study shows that before the tuning process, a system takes 156 milliseconds to execute the query and after implementing the proposed query tuning process, the execution time decreases to less than one millisecond. It means hundred times performance improvement on the query execution. The outcome of the study proved that the query execution time decreased after implementing the proposed query tuning process in the system.

  20. Perm: Processing provenance and data on the same data model through query rewriting

    OpenAIRE

    Glavic, B; Alonso, G

    2009-01-01

    Data provenance is information that describes how a given data item was produced. The provenance includes source and intermediate data as well as the transformations involved in producing the concrete data item. In the context of a relational databases, the source and intermediate data items are relations, tuples and attribute values. The transformations are SQL queries and/or functions on the relational data items. Existing approaches capture provenance information by extending the underl...

  1. Increasing user participation: An exploratory study of querying on the Facebook and Twitter platforms

    OpenAIRE

    Crowley, Caren; Daniels, Wilfried; Bachiller Soler, Rafael; Joosen, Wouter; Hughes, Danny

    2014-01-01

    Participatory applications frequently rely upon a crowd–sourced community of users who contribute data and content to deliver a service. The success or failure of participatory applications is dependent on developing and maintaining a community of responsive users. This paper reports the results of an exploratory 30–day study examining user responsiveness to query messages. In total 3,055 check–in requests were sent via the online social networks Facebook or Twitter to 70 participants who wer...

  2. TRUST BASED AUTOMATIC QUERY FORMULATION SEARCH ON EXPERT AND KNOWLEDGE USERS SYSTEMS

    Directory of Open Access Journals (Sweden)

    K. Sridharan

    2014-01-01

    Full Text Available Due to enhance in complexity of services, there is a necessity for dynamic interaction models. For a service-oriented system to work properly, we need a context-sensitive trust based search. Automatic information transfer is also deficient when unexpected query is given. However, it shows that search engines are vulnerable in answering intellectual queries and shows an unreliable outcome. The user cannot have a fulfillment with these results due to lack of trusts on blogs. In our modified trust algorithm, which process exact skill matching and retrieval of information based on proper content rank. Our contribution to this system is new modified trust algorithm with automatic formulation of meaningful query search to retrieve the exact contents from the top-ranked documents based on the expert rank and their content quality verified of their resources provided. Some semantic search engines cannot show their important performance in improving precision and lowering recall. It hence effectively reduces complexity in combining HPS and software services.

  3. Head lice surveillance on a deregulated OTC-sales market: a study using web query data.

    Directory of Open Access Journals (Sweden)

    Johan Lindh

    Full Text Available The head louse, Pediculus humanus capitis, is an obligate ectoparasite that causes infestations of humans. Studies have demonstrated a correlation between sales figures for over-the-counter (OTC treatment products and the number of humans with head lice. The deregulation of the Swedish pharmacy market on July 1, 2009, decreased the possibility to obtain complete sale figures and thereby the possibility to obtain yearly trends of head lice infestations. In the presented study we wanted to investigate whether web queries on head lice can be used as substitute for OTC sales figures. Via Google Insights for Search and Vårdguiden medical web site, the number of queries on "huvudlöss" (head lice and "hårlöss" (lice in hair were obtained. The analysis showed that both the Vårdguiden series and the Google series were statistically significant (p<0.001 when added separately, but if the Google series were already included in the model, the Vårdguiden series were not statistically significant (p = 0.5689. In conclusion, web queries can detect if there is an increase or decrease of head lice infested humans in Sweden over a period of years, and be as reliable a proxy as the OTC-sales figures.

  4. BlinkDB: Queries with Bounded Errors and Bounded Response Times on Very Large Data

    CERN Document Server

    Agarwal, Sameer; Mozafari, Barzan; Madden, Samuel; Stoica, Ion

    2012-01-01

    Today's web is predominantly data-driven. Corporations, businesses and netizens are increasingly depending on enormous amounts of data (spanning terabytes or even petabytes in size) to make intelligent business and personal decisions. Often the time it takes to make these decisions is critical. Unfortunately, quickly analyzing large volumes of data poses significant challenges. For instance, scanning 1TB of data may take minutes, even when the data is spread across hundreds of machines and read in parallel. In this paper, we present BlinkDB, a massively parallel, sampling-based approximate query engine for running interactive queries on large volumes of data. The key observation in BlinkDB is that one can make perfect decisions in the absence of perfect answers. For example, reliably detecting a malfunctioning server in a distributed collection of system logs does not require knowing every request the server processed. Based on this insight, BlinkDB allows one to tradeoff between query accuracy and response t...

  5. Querying Co-regulated Genes on Diverse Gene Expression Datasets Via Biclustering.

    Science.gov (United States)

    Deveci, Mehmet; Küçüktunç, Onur; Eren, Kemal; Bozdağ, Doruk; Kaya, Kamer; Çatalyürek, Ümit V

    2016-01-01

    Rapid development and increasing popularity of gene expression microarrays have resulted in a number of studies on the discovery of co-regulated genes. One important way of discovering such co-regulations is the query-based search since gene co-expressions may indicate a shared role in a biological process. Although there exist promising query-driven search methods adapting clustering, they fail to capture many genes that function in the same biological pathway because microarray datasets are fraught with spurious samples or samples of diverse origin, or the pathways might be regulated under only a subset of samples. On the other hand, a class of clustering algorithms known as biclustering algorithms which simultaneously cluster both the items and their features are useful while analyzing gene expression data, or any data in which items are related in only a subset of their samples. This means that genes need not be related in all samples to be clustered together. Because many genes only interact under specific circumstances, biclustering may recover the relationships that traditional clustering algorithms can easily miss. In this chapter, we briefly summarize the literature using biclustering for querying co-regulated genes. Then we present a novel biclustering approach and evaluate its performance by a thorough experimental analysis. PMID:26626937

  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. Anonymous Mobile Payment Solution

    Directory of Open Access Journals (Sweden)

    Alhaj Ali Jalila

    2015-09-01

    Full Text Available The evolution and increasing popularity of mobile handheld devices has led to the development of payment applications. The global acceptance of mobile payments is hindered by security and privacy concerns. One of the main problems evoked is the anonymity related with banking transactions. In this paper I propose a new secured architecture for mobile banking. Anonymity and privacy protection are the measures to be enhanced in order to satisfy people’s current needs. The banking platform must provide the highest level of security for messages exchanged between bank and the customer.

  8. Anonymous Broadcast Messages

    Directory of Open Access Journals (Sweden)

    Dragan Lazic

    2013-01-01

    Full Text Available The Dining Cryptographer network (or DC-net is a privacy preserving communication protocol devised by David Chaum for anonymous message publication. A very attractive feature of DC-nets is the strength of its security, which is inherent in the protocol and is not dependent on other schemes, like encryption. Unfortunately the DC-net protocol has a level of complexity that causes it to suffer from exceptional communication overhead and implementation difficulty that precludes its use in many real-world use-cases. We have designed and created a DC-net implementation that uses a pure client-server model, which successfully avoids much of the complexity inherent in the DC-net protocol. We describe the theory of DC-nets and our pure client-server implementation, as well as the compromises that were made to reduce the protocol’s level of complexity. Discussion centers around the details of our implementation of DC-net.

  9. Federated SPARQL Query Processing Reconciling Diversity, Flexibility and Performance on the Web of Data

    OpenAIRE

    Basca, C

    2015-01-01

    Querying the ever-growing Web of Data poses a significant challenge in today’s Semantic Web. The complete lack of any centralised control leads to potentially arbitrary data distribution, high variability of latency between hosts participating in query answering, and, in the extreme, even the (sudden) unavailability of some hosts during query execution. In this thesis we address the question of how to efficiently query the Web of Data while taking into account its scale, diversity and unrelia...

  10. Mining Longitudinal Web Queries: Trends and Patterns.

    Science.gov (United States)

    Wang, Peiling; Berry, Michael W.; Yang, Yiheng

    2003-01-01

    Analyzed user queries submitted to an academic Web site during a four-year period, using a relational database, to examine users' query behavior, to identify problems they encounter, and to develop techniques for optimizing query analysis and mining. Linguistic analyses focus on query structures, lexicon, and word associations using statistical…

  11. Foreword for the special issue of selected papers from the 7th EDBT/ICDT Workshop on Privacy and Anonymity in Information Society (PAIS 2014

    Directory of Open Access Journals (Sweden)

    Traian Marius Truta

    2015-04-01

    Full Text Available The seventh Workshop on Privacy and Anonymity in Information Society (PAIS 2014 was held in conjunction with the International Conference on Extending Database Technology (EDBT and International Conference on Database Theory (ICDT in Athens, Greece. The PAIS 2014 workshop provided an open yet focused platform for researchers and practitioners from fields such as computer science, statistics, healthcare informatics, and law to discuss and present current research challenges and advances in data privacy and anonymity research. The present special issue contains three extended papers that have been selected as the best three papers presented at PAIS 2014 workshop.

  12. A flexible approach to distributed data anonymization.

    Science.gov (United States)

    Kohlmayer, Florian; Prasser, Fabian; Eckert, Claudia; Kuhn, Klaus A

    2014-08-01

    Sensitive biomedical data is often collected from distributed sources, involving different information systems and different organizational units. Local autonomy and legal reasons lead to the need of privacy preserving integration concepts. In this article, we focus on anonymization, which plays an important role for the re-use of clinical data and for the sharing of research data. We present a flexible solution for anonymizing distributed data in the semi-honest model. Prior to the anonymization procedure, an encrypted global view of the dataset is constructed by means of a secure multi-party computing (SMC) protocol. This global representation can then be anonymized. Our approach is not limited to specific anonymization algorithms but provides pre- and postprocessing for a broad spectrum of algorithms and many privacy criteria. We present an extensive analytical and experimental evaluation and discuss which types of methods and criteria are supported. Our prototype demonstrates the approach by implementing k-anonymity, ℓ-diversity, t-closeness and δ-presence with a globally optimal de-identification method in horizontally and vertically distributed setups. The experiments show that our method provides highly competitive performance and offers a practical and flexible solution for anonymizing distributed biomedical datasets. PMID:24333850

  13. Preserving Communities in Anonymized Social Networks

    Directory of Open Access Journals (Sweden)

    Alina Campan

    2015-04-01

    Full Text Available Social media and social networks are embedded in our society to a point that could not have been imagined only ten years ago. Facebook, LinkedIn, and Twitter are already well known social networks that have a large audience in all age groups. The amount of data that those social sites gather from their users is continually increasing and this data is very valuable for marketing, research, and various other purposes. At the same time, this data usually contain a significant amount of sensitive information which should be protected against unauthorized disclosure. To protect the privacy of individuals, this data must be anonymized such that the risk of re-identification of specific individuals is very low. In this paper we study if anonymized social networks preserve existing communities from the original social networks. To perform this study, we introduce two approaches to measure the community preservation between the initial network and its anonymized version. In the first approach we simply count how many nodes from the original communities remained in the same community after the processes of anonymization and de-anonymization. In the second approach we consider the community preservation for each node individually. Specifically, for each node, we compare the original and final communities to which the node belongs. To anonymize social networks we use two models, namely, k-anonymity for social networks and k-degree anonymity. To determine communities in social networks we use an existing community detection algorithm based on modularity quality function. Our experiments on publically available datasets show that anonymized social networks satisfactorily preserve the community structure of their original networks.

  14. Subsumption Checking between Concept Queries in Different Ontologies Based on Mutual Instances

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    This paper proposes a checking method based on mutual instances and discusses three key problems in the method: how to deal with mistakes in the mutual instances and how to deal with too many or too few mutual instances. It provides the checking based on the weighted mutual instances considering fault tolerance, gives a way to partition the large-scale mutual instances, and proposes a process greatly reducing the manual annotation work to get more mutual instances. Intension annotation that improves the checking method is also discussed. The method is practical and effective to check subsumption relations between concept queries in different ontologies based on mutual instances.

  15. An Efficient Algorithm for Query Transformation in Semantic Query Optimization

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Semantic query optimization (SQO) is comparatively a recent approach for the transformation of given query into equivalent alternative query using matching rules in order to select an optimal query based on the costs of executing alternative queries. The key aspect of the algorithm proposed here is that previous proposed SQO techniques can be considered equally in the uniform cost model, with which optimization opportunities will not be missed. At the same time, the authors used the implication closure to guarantee that any matched rule will not be lost. The authors implemented their algorithm for the optimization of decomposed sub-query in local database in Multi-Database Integrator (MDBI), which is a multidatabase project. The experimental results verify that this algorithm is effective in the process of SQO.

  16. Graphical querying of model-driven spreadsheets

    OpenAIRE

    Cunha, Jácome Miguel Costa; Fernandes, João Paulo de Sousa Ferreira; Pereira, Rui Alexandre Afonso; Saraiva, João Alexandre

    2014-01-01

    This paper presents a graphical interface to query modeldriven spreadsheets, based on experience with previous work and empirical studies in querying systems, to simplify query construction for typical end-users with little to no knowledge of SQL. We briefly show our previous text based model-driven querying system. Afterwards, we detail our graphical model-driven querying interface, explaining each part of the interface and showing an example. To validate our work, we executed an empirica...

  17. Scalable Package Queries in Relational Database Systems

    OpenAIRE

    Brucato, Matteo; Beltran, Juan Felipe; Abouzied, Azza; Meliou, Alexandra

    2015-01-01

    Traditional database queries follow a simple model: they define constraints that each tuple in the result must satisfy. This model is computationally efficient, as the database system can evaluate the query conditions on each tuple individually. However, many practical, real-world problems require a collection of result tuples to satisfy constraints collectively, rather than individually. In this paper, we present package queries, a new query model that extends traditional database queries to...

  18. 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.

  19. Selective Flooding Based on Relevant Nearest-Neighbor using Query Feedback and Similarity across Unstructured Peer-to-Peer Networks

    Directory of Open Access Journals (Sweden)

    Iskandar Ishak

    2009-01-01

    Full Text Available Problem statement: Efficient searching is a fundamental problem for unstructured peer to peer networks. Flooding requires a lot of resources in the network and thus will increase the search cost. Searching approach that utilizes minimum network resources is required to produce efficient searching in the robust and dynamic peer-to-peer network. Approach: This study addressed the need for efficient flood-based searching in unstructured peer-to-peer network by considering the content of query and only selecting peers that were most related to the query given. We used minimum information to perform efficient peer selection by utilizing the past queries data and the query message. We exploited the nearest-neighbor concept on our query similarity and query hits space metrics for selecting the most relevant peers for efficient searching. Results: As demonstrated by extensive simulations, our searching scheme achieved better retrieval and low messages consumption. Conclusion: This study suggested that, in an unstructured peer-to-peer network, flooding that was based on the selection of relevant peers, can improve searching efficiency.

  20. Working with jqTouch to build websites on top of jQuery

    CERN Document Server

    David, Matthew

    2012-01-01

    Using jqTouch, an open source solution, is a fast way for you to convert a static Web page into looking like a native iPhone or Android app. In this short ebook find out how you can use the Open Source jqTouch Library to extend the functionality built into jQuery to build Web sites that run on your iOS and Android phones but look and interact as if they are native apps. You will also discover how to create custom interfaces, screen flipping, and set themes with jqTouch.

  1. Querying Safety Cases

    Science.gov (United States)

    Denney, Ewen W.; Naylor, Dwight; Pai, Ganesh

    2014-01-01

    Querying a safety case to show how the various stakeholders' concerns about system safety are addressed has been put forth as one of the benefits of argument-based assurance (in a recent study by the Health Foundation, UK, which reviewed the use of safety cases in safety-critical industries). However, neither the literature nor current practice offer much guidance on querying mechanisms appropriate for, or available within, a safety case paradigm. This paper presents a preliminary approach that uses a formal basis for querying safety cases, specifically Goal Structuring Notation (GSN) argument structures. Our approach semantically enriches GSN arguments with domain-specific metadata that the query language leverages, along with its inherent structure, to produce views. We have implemented the approach in our toolset AdvoCATE, and illustrate it by application to a fragment of the safety argument for an Unmanned Aircraft System (UAS) being developed at NASA Ames. We also discuss the potential practical utility of our query mechanism within the context of the existing framework for UAS safety assurance.

  2. 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.

  3. 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......-computer interaction. The special track covers some some specific and, typically, newer fields, namely: environmental scanning for strategic early warning; generating linguistic descriptions of data; advances in fuzzy querying and fuzzy databases: theory and applications; fusion and ensemble techniques for on-line...

  4. Privacy Preserving Quantum Anonymous Transmission via Entanglement Relay

    Science.gov (United States)

    Yang, Wei; Huang, Liusheng; Song, Fang

    2016-06-01

    Anonymous transmission is an interesting and crucial issue in computer communication area, which plays a supplementary role to data privacy. In this paper, we put forward a privacy preserving quantum anonymous transmission protocol based on entanglement relay, which constructs anonymous entanglement from EPR pairs instead of multi-particle entangled state, e.g. GHZ state. Our protocol achieves both sender anonymity and receiver anonymity against an active adversary and tolerates any number of corrupt participants. Meanwhile, our protocol obtains an improvement in efficiency compared to quantum schemes in previous literature.

  5. Privacy Preserving Quantum Anonymous Transmission via Entanglement Relay.

    Science.gov (United States)

    Yang, Wei; Huang, Liusheng; Song, Fang

    2016-01-01

    Anonymous transmission is an interesting and crucial issue in computer communication area, which plays a supplementary role to data privacy. In this paper, we put forward a privacy preserving quantum anonymous transmission protocol based on entanglement relay, which constructs anonymous entanglement from EPR pairs instead of multi-particle entangled state, e.g. GHZ state. Our protocol achieves both sender anonymity and receiver anonymity against an active adversary and tolerates any number of corrupt participants. Meanwhile, our protocol obtains an improvement in efficiency compared to quantum schemes in previous literature. PMID:27247078

  6. Security and Anonymity of Bitcoin Payments

    OpenAIRE

    Korošec, Peter

    2016-01-01

    This thesis presents the digital payment system Bitcoin. It describes the cryptography on which the system is based. Presented are the short history of the system and the principles of how it works. Highlighted are the state of anonymity that the system provides while making payments and the safety it guarantees while executing transactions. Within the context of anonymity, the state of masking the users identity within the payment system is described, together with warnings and mechanisms to...

  7. The Impact of Counselor Recovery Status Similarity on Perceptions of Attractiveness with Members of Alcoholics Anonymous: An Exception to the Repulsion Hypothesis

    Science.gov (United States)

    Priester, Paul E.; Azen, Razia; Speight, Suzette; Vera, Elizabeth M.

    2007-01-01

    This study explores the impact of counselor alcoholism recovery status on perceptions of recovering alcoholics who are active members of Alcoholics Anonymous. The participants (n = 116) were given a description of an analogue counselor and rated this counselor using the "Counselor Rating Form-Short." There were three forms of the analogue…

  8. A Comparison of Anonymous versus Identifiable e-Peer Review on College Student Writing Performance and the Extent of Critical Feedback

    Science.gov (United States)

    Lu, Ruiling; Bol, Linda

    2007-01-01

    Peer review has become commonplace in composition courses and is increasingly employed in the context of telecommunication technology. The purpose of this experiment was to compare the effects of anonymous and identifiable electronic peer (e-peer) review on college student writing performance and the extent of critical peer feedback. Participants…

  9. Data Caching for XML Query

    Institute of Scientific and Technical Information of China (English)

    SU Fei; CI Lin-lin; ZHU Li-ping; ZHAO Xin-xin

    2006-01-01

    In order to apply the technique of data cache to extensible markup language (XML) database system, the XML-cache system to support data cache for XQuery is presented. According to the character of XML, the queries with nesting are normalized to facilitate the following operation. Based on the idea of incomplete tree, using the document type definition (DTD) schema tree and conditions from normalized XQuery, the results of previous queries are maintained to answer new queries, at the same time, the remainder queries are sent to XML database at the back. The results of experiment show all applications supported by XML database can use this technique to cache data for future use.

  10. 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

  11. XPath Whole Query Optimization

    CERN Document Server

    Maneth, Sebastian

    2010-01-01

    Previous work reports about SXSI, a fast XPath engine which executes tree automata over compressed XML indexes. Here, reasons are investigated why SXSI is so fast. It is shown that tree automata can be used as a general framework for fine grained XML query optimization. We define the "relevant nodes" of a query as those nodes that a minimal automaton must touch in order to answer the query. This notion allows to skip many subtrees during execution, and, with the help of particular tree indexes, even allows to skip internal nodes of the tree. We efficiently approximate runs over relevant nodes by means of on-the-fly removal of alternation and non-determinism of (alternating) tree automata. We also introduce many implementation techniques which allows us to efficiently evaluate tree automata, even in the absence of special indexes. Through extensive experiments, we demonstrate the impact of the different optimization techniques.

  12. Geospatial-Enabled RuleML in a Study on Querying Respiratory Disease Information

    DEFF Research Database (Denmark)

    Gao, Sheng; Boley, Harold; Mioc, Darka;

    2009-01-01

    health data query and representation framework is proposed through the formalization of spatial information. We include the geometric representation in RuleML deduction, and apply ontologies and rules for querying and representing health information. Corresponding geospatial built-ins were implemented...... as an extension to OO jDREW. Case studies were carried out using geospatial-enabled RuleML queries for respiratory disease information. The paper thus demonstrates the use of RuleML for geospatial-semantic querying and representing of health information....

  13. On describing human white matter anatomy: the white matter query language.

    Science.gov (United States)

    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 definitions include adjacent gray and white matter regions, and rules for spatial relations. This enables automated coherent labeling of white matter anatomy across subjects. We use our method to encode anatomical knowledge in human white matter describing 10 association and 8 projection tracts per hemisphere and 7 commissural tracts. The technique is shown to be comparable in accuracy to manual labeling. We present results applying this framework to create a white matter atlas from 77 healthy subjects, and we use this atlas in a proof-of-concept study to detect tract changes specific to schizophrenia. PMID:24505722

  14. 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. PMID:21078644

  15. On Mobility Management in Multi-Sink Sensor Networks for Geocasting of Queries

    Directory of Open Access Journals (Sweden)

    Paul Havinga

    2011-12-01

    Full Text Available In order to efficiently deal with location dependent messages in multi-sink wireless sensor networks (WSNs, it is key that the network informs sinks what geographical area is covered by which sink. The sinks are then able to efficiently route messages which are only valid in particular regions of the deployment. In our previous work (see the 5th and 6th cited documents, we proposed a combined coverage area reporting and geographical routing protocol for location dependent messages, for example, queries that are injected by sinks. In this paper, we study the case where we have static sinks and mobile sensor nodes in the network. To provide up-to-date coverage areas to sinks, we focus on handling node mobility in the network. We discuss what is a better method for updating the routing structure (i.e., routing trees and coverage areas to handle mobility efficiently: periodic global updates initiated from sinks or local updates triggered by mobile sensors. Simulation results show that local updating perform very well in terms of query delivery ratio. Local updating has a better scalability to increasing network size. It is also more energy efficient than ourpreviously proposed approach, where global updating in networks have medium mobility rate and speed.

  16. 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. PMID:24504081

  17. A solution of spatial query processing and query optimization for spatial databases

    Institute of Scientific and Technical Information of China (English)

    YUAN Jie; XIE Kun-qing; MA Xiu-jun; ZHANG Min; SUN Le-bin

    2004-01-01

    Recently, attention has been focused on spatial query language which is used to query spatial databases. A design of spatial query language has been presented in this paper by extending the standard relational database query language SQL. It recognizes the significantly different requirements of spatial data handling and overcomes the inherent problems of the application of conventional database query languages. This design is based on an extended spatial data model, including the spatial data types and the spatial operators on them. The processing and optimization of spatial queries have also been discussed in this design. In the end, an implementation of this design is given in a spatial query subsystem.

  18. On-demand information retrieval in sensor networks with localised query and energy-balanced data collection.

    Science.gov (United States)

    Teng, Rui; Zhang, Bing

    2011-01-01

    On-demand information retrieval enables users to query and collect up-to-date sensing information from sensor nodes. Since high energy efficiency is required in a sensor network, it is desirable to disseminate query messages with small traffic overhead and to collect sensing data with low energy consumption. However, on-demand query messages are generally forwarded to sensor nodes in network-wide broadcasts, which create large traffic overhead. In addition, since on-demand information retrieval may introduce intermittent and spatial data collections, the construction and maintenance of conventional aggregation structures such as clusters and chains will be at high cost. In this paper, we propose an on-demand information retrieval approach that exploits the name resolution of data queries according to the attribute and location of each sensor node. The proposed approach localises each query dissemination and enable localised data collection with maximised aggregation. To illustrate the effectiveness of the proposed approach, an analytical model that describes the criteria of sink proxy selection is provided. The evaluation results reveal that the proposed scheme significantly reduces energy consumption and improves the balance of energy consumption among sensor nodes by alleviating heavy traffic near the sink.

  19. Anonymization of big data based on hybrid tree%基于混合式子树算法的大数据匿名化

    Institute of Scientific and Technical Information of China (English)

    孙炯宁

    2015-01-01

    The top-down specialization( TDS) and the bottom-up generalization( BUG) are two ways to fulfill the sub-tree anonymization. However,existing approaches for sub-tree anonymization fall short of parallelization capability,thereby lacking scalability in handling big data on cloud. Still,both the TDS and the BUG suffer from poor performances for certain value of the K anonymity parameter when they are utilized individually. In view of that,a hybrid approach combining the TDS and the BUG for efficient sub-tree anonymization over big data is proposed. Further,the MapReduce is designed based algorithms for two components ( TDS and BUG ) to gain the high scalability by exploiting powerful computation capability of cloud. Experiment evaluations demonstrate that the hybrid approach significantly improves the scalability and the efficiency of the sub-tree anonymization scheme over existing approaches.%自顶而下具体化( TDS)和自底向上泛化( BUG)是子树匿名化的主要方法,但其并行能力不足,易导致在云数据处理中缺乏可扩展性。当TDS和BUG分开使用时,很难准确确定K匿名参数。针对这一问题,该文提出一种在大数据中进行有效数据匿名化的基于TDS和BUG的混合方法,设计了基于该混合方法的MapReduce模型,以提高云计算能力的可扩展性。实验表明,与现有方法相比,该混合法可以显著提高扩展性和子树匿名化的效率。

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

    NARCIS (Netherlands)

    Velde, Van der F.

    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 surro

  1. Form and Function: The Impact of Query Term and Operator Usage on Web Search Results.

    Science.gov (United States)

    Lucas, Wendy; Topi, Heikki

    2002-01-01

    Describes a study of college students that investigated Web-based search engine queries and compared relevancy ratings with expert-formulated queries. Considers the number of subject terms used and the use of Boolean operators and discuses the need for designing search engine interfaces that provide greater support in term selection and operator…

  2. Anonymity in Large Societies

    OpenAIRE

    Andrei Gomberg; Cesar Martinelli; Ricard Torres

    2002-01-01

    In a social choice model with an infinite number of agents, there may occur "equal size" coalitions that a preference aggregation rule should treat in the same manner. We introduce an axiom of equal treatment with respect to a measure of coalition size and explore its interaction with common axioms of social choice. We show that, provided the measure space is sufficiently rich in coalitions of the same measure, the new axiom is the natural extension of the concept of anonymity, and in particu...

  3. A Simplistic Mechanism for Query Cost Optimization

    Directory of Open Access Journals (Sweden)

    Debopam De

    2015-06-01

    Full Text Available The cost of a database query can be optimized so that a more efficient query can be generated. However not many tools are available which work independently to optimize the cost of a query. This article is based on a tool that we developed to serve the purpose. It uses an Oracle Database and Linear Programming Problem concepts to evaluate the optimum cost of the query and compares it with the original cost of the query that the user gives. The optimum cost can also be used to devise a new query which serves the same purpose as the original one and with reduced cost.

  4. Cache-Based Aggregate Query Shipping: An Efficient Scheme of Distributed OLAP Query Processing

    Institute of Scientific and Technical Information of China (English)

    Hua-Ming Liao; Guo-Shun Pei

    2008-01-01

    Our study introduces a novel distributed query plan refinement phase in an enhanced architecture of distributed query processing engine (DQPE). Query plan refinement generates potentially efficient distributed query plan by reusable aggregate query shipping (RAQS) approach. The approach improves response time at the cost of pre-processing time. If theoverheads could not be compensated by query results reusage, RAQS is no more favorable. Therefore a global cost estimation model is employed to get proper operators: RR_Agg, R_Agg, or R_Scan. For the purpose of reusing results of queries with aggregate function in distributed query processing, a multi-level hybrid view caching (HVC) scheme is introduced. The scheme retains the advantages of partial match and aggregate query results caching. By our solution, evaluations with distributed TPC-H queries show significant improvement on average response time.

  5. 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.

  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. 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

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

    DEFF Research Database (Denmark)

    Dolog, Peter; Stuckenschmidt, Heiner; Wache, Holger

    Research in Cooperative Query answering is triggered by the observation that users are often not able to correctly formulate queries to databases that return the intended result. Due to a lack of knowledge of the contents and the structure of a database, users will often only be able to provide...... 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...

  9. A Practical Approach for Scalable Conjunctive Query Answering on Acyclic {EL}^+ Knowledge Base

    Science.gov (United States)

    Mei, Jing; Liu, Shengping; Xie, Guotong; Kalyanpur, Aditya; Fokoue, Achille; Ni, Yuan; Li, Hanyu; Pan, Yue

    Conjunctive query answering for {EL}^{++} ontologies has recently drawn much attention, as the Description Logic {EL}^{++} captures the expressivity of many large ontologies in the biomedical domain and is the foundation for the OWL 2 EL profile. In this paper, we propose a practical approach for conjunctive query answering in a fragment of {EL}^{++}, namely acyclic {EL}^+, that supports role inclusions. This approach can be implemented with low cost by leveraging any existing relational database management system to do the ABox data completion and query answering. We conducted a preliminary experiment to evaluate our approach using a large clinical data set and show our approach is practical.

  10. Foreword for the special issue of selected papers from the 7th EDBT/ICDT Workshop on Privacy and Anonymity in Information Society (PAIS 2014)

    OpenAIRE

    Traian Marius Truta; Li Xiong; Farshad Fotouhi

    2015-01-01

    The seventh Workshop on Privacy and Anonymity in Information Society (PAIS 2014) was held in conjunction with the International Conference on Extending Database Technology (EDBT) and International Conference on Database Theory (ICDT) in Athens, Greece. The PAIS 2014 workshop provided an open yet focused platform for researchers and practitioners from fields such as computer science, statistics, healthcare informatics, and law to discuss and present current research challenges and advances ...

  11. 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...

  12. Indexing for summary queries

    DEFF Research Database (Denmark)

    Yi, Ke; Wang, Lu; Wei, Zhewei

    2014-01-01

    Database queries can be broadly classified into two categories: reporting queries and aggregation queries. The former retrieves a collection of records from the database that match the query's conditions, while the latter returns an aggregate, such as count, sum, average, or max (min), of a parti...

  13. Reflections on the Ritual process in Mexican Communities of Alcoholics Anonymous

    Directory of Open Access Journals (Sweden)

    Palacios Ramírez, José

    2008-12-01

    Full Text Available The author conveys his reflections on the symbolic aspects and ritual character of the therapeutic communities of rehabilitation of alcoholics, known as “Alcoholic Anonymous” (AA. He did ethnographic fieldwork among AA communities of Ciudad Victoria, in Tamaulipas, northern Mexico. These communities, facing a problem often neglected by both government and society in Mexico, yet holding a position of subalternity and marginality in the country, offer a spiritual way out to those alcoholics who approach them. Their activities are of interest for a discussion of ritual in current contexts. In addition, the communities are illuminating for many of the key aspects of the comparative ethnographic analysis of ritual.

    El objeto de este trabajo es apuntar algunas líneas de reflexión sobre los aspectos simbólicos y de carácter ritual que presentan las comunidades terapéuticas de rehabilitación de alcohólicos, Alcohólicos Anónimos (AA. Para ello parto del trabajo de campo etnográfico realizado en agrupaciones de AA en Ciudad Victoria, Tamaulipas, al norte de México. Estas comunidades de apoyo a alcohólicos, desde una posición de subalternidad y marginalidad, ante una problemática casi siempre obviada por la sociedad y el gobierno mexicano, ofrecen una “salida” de corte espiritual a quienes se acercan a ellas, por lo que resultan interesantes para la reflexión sobre el ritual en contextos actuales. Por otro lado, estas comunidades presentan muchos de los aspectos clave en el análisis etnográfico comparativo de los ritos.

  14. 基于 DAA 和 TLS 的匿名远程证明协议%Anonymous remote attestation protocol based on DAA and TLS

    Institute of Scientific and Technical Information of China (English)

    张大伟; 韩臻; 蒋逸尘; 黎妹红

    2014-01-01

    To prevent the masquerading attack in the remote attestation with the direct anonymous at-testation (DAA ) ,a anonymous remote attestation protocol was proposed based on DAA and the transport layer security (TLS) protocol .The trusted platform module was utilized to measure the platform configuration and anonymous identity ,and the signature generated .The new identity au-thentication and certificate verification method were designed .The remote attestation information was transmitted with supplemental messages in TLS .The anonymous attestation ,integrity reporting and key agreement mechanisms were integrated so as to build a trusted anonymous channel .Security anal-ysis show s that our protocol satisfies unforgeability ,anonymity ,user-controllable linkability and un-cloneability in identity authentication as well as resists the replay attack and the masquerading attack . The proposed protocol is easily deployed because of the compatibility with the TLS extension frame-work .%为了解决使用直接匿名证明方法进行远程证明易受伪装攻击的问题,提出了一种基于直接匿名证明和安全传输层协议(TLS)的匿名远程证明协议。使用可信平台模块,完成平台配置和匿名身份的度量并生成签名信息;改进身份认证和证书校验机制,并使用T LS协议的扩展消息传输远程证明内容;结合匿名证明、完整性报告和密钥协商机制设计总体协议,从而在交互双方构建出匿名认证的可信信道。分析表明:改进方案满足身份认证的不可伪造性、匿名性、可控的可链接性和不可克隆性,能够抵御重放攻击和伪装攻击,且设计的协议兼容扩展的T LS协议架构,便于部署。

  15. Medical students’ education on organ donation and its evaluation during six consecutive years: results of a voluntary, anonymous educational intervention study

    OpenAIRE

    Radunz, Sonia; Benkö, Tamás; Stern, Sabrina; Saner, Fuat H.; Paul, Andreas; Kaiser, Gernot M

    2015-01-01

    Background One of the main reasons for organ shortage is insufficient education on organ donation. Knowledgeable medical students could share the information with friends and families resulting in a positive attitude to organ donation of the general public. Methods During six consecutive years (2009 to 2014), we conducted a voluntary, anonymous educational intervention study on organ donation among fourth year medical students in the course of the main surgery lecture at the University of Ess...

  16. Implementation of SPARQL Query Engine Based on CouchDB%基于CouchDB的SPARQL查询引擎实现

    Institute of Scientific and Technical Information of China (English)

    彭义; 倪传蕾; 柏文阳

    2014-01-01

    Traditional SPARQL query engines optimize queries in terms of triple pattern as basic unit. This brings too many join operations in the face of SPARQL queries comprising many triple patterns,which lead to much query overhead. In this paper,taking the advantage of storing and quering of document-oriented database,propose a subject-classification approach to store RDF triples. RDF triples are parti-tioned into various classes in terms of identical subjects,and saved to the documents of the database. Triple patterns are classified accord-ing to their subjects as well,composing the query graph based on subject-related block. The method of selectivity estimation is improved on the new query graph. Using a document-oriented databse CouchDB to build a SPARQL query engine,the experiment proves the ap-proach is capable of improving the efficiency of SPARQL basic graph pattern query handling.%传统的SPARQL查询引擎在处理查询时以三元组模式为基本单位做查询优化处理,在三元组模式较多时存在着过多的连接操作,开销比较大。文中基于文档数据库的存储和查询特点,提出一种利用主语分类的方式来存储RDF数据的方法,将不同的RDF三元组按主语分成不同的类,并存入文档数据库的文档中。在处理SPARQL查询时将三元组模式也按照主语分类,构成以主语相关块为单位的查询图,并提出一种基于属性相关性的选择度估计方法来优化查询执行计划。文中利用文档数据库CouchDB实现了新的SPARQL查询引擎,实验证明文中的方法能够提高SPARQL基本图模式查询的效率。

  17. Reading (and Not Reading Anonymity: Daniel Defoe, An Essay on the Regulation of the Press and A Vindication of the Press

    Directory of Open Access Journals (Sweden)

    Mark Vareschi

    2015-06-01

    Full Text Available In this essay I take up the anonymous An Essay on the Regulation of the Press (1704 and A Vindication of the Press (1718, both regularly attributed to Daniel Defoe. While the pamphlets themselves consider anonymity essential to a work being read and interpreted, paradoxically, twentieth- and twenty-first century critics insist on correct attribution as the starting point for interpretation. The consequences and benefits of authorial attribution to these, and other, minor works are not insignificant. The attribution of authorship to a known author ensures that a work will survive; it may even ensure that a work is subject to study and analysis. However, authorial attribution may also foreclose study and analysis because the attributed work, if it is to be by the named author, must be made to cohere within a larger body of work.

  18. SPIN Query Tools for De-identified Research on a Humongous Database

    OpenAIRE

    McDonald, Clement J.; Dexter, Paul; Schadow, Gunther; Chueh, Henry C.; Abernathy, Greg; Hook, John; Blevins, Lonnie; Overhage, J Marc; Jules J Berman

    2005-01-01

    The Shared Pathology Informatics Network (SPIN), a research initiative of the National Cancer Institute, will allow for the retrieval of more than 4 million pathology reports and specimens. In this paper, we describe the special query tool as developed for the Indianapolis/Regenstrief SPIN node, integrated into the ever-expanding Indiana Network for Patient care (INPC). This query tool allows for the retrieval of de-identified data sets using complex logic, auto-coded final ...

  19. Anonymous Fingerprinting with Robust QIM Watermarking Techniques

    Directory of Open Access Journals (Sweden)

    R. L. Lagendijk

    2007-12-01

    Full Text Available Fingerprinting is an essential tool to shun legal buyers of digital content from illegal redistribution. In fingerprinting schemes, the merchant embeds the buyer's identity as a watermark into the content so that the merchant can retrieve the buyer's identity when he encounters a redistributed copy. To prevent the merchant from dishonestly embedding the buyer's identity multiple times, it is essential for the fingerprinting scheme to be anonymous. Kuribayashi and Tanaka, 2005, proposed an anonymous fingerprinting scheme based on a homomorphic additive encryption scheme, which uses basic quantization index modulation (QIM for embedding. In order, for this scheme, to provide sufficient security to the merchant, the buyer must be unable to remove the fingerprint without significantly degrading the purchased digital content. Unfortunately, QIM watermarks can be removed by simple attacks like amplitude scaling. Furthermore, the embedding positions can be retrieved by a single buyer, allowing for a locally targeted attack. In this paper, we use robust watermarking techniques within the anonymous fingerprinting approach proposed by Kuribayashi and Tanaka. We show that the properties of an additive homomorphic cryptosystem allow for creating anonymous fingerprinting schemes based on distortion compensated QIM (DC-QIM and rational dither modulation (RDM, improving the robustness of the embedded fingerprints. We evaluate the performance of the proposed anonymous fingerprinting schemes under additive-noise and amplitude-scaling attacks.

  20. An Examination of Natural Language as a Query Formation Tool for Retrieving Information on E-Health from Pub Med.

    Science.gov (United States)

    Peterson, Gabriel M.; Su, Kuichun; Ries, James E.; Sievert, Mary Ellen C.

    2002-01-01

    Discussion of Internet use for information searches on health-related topics focuses on a study that examined complexity and variability of natural language in using search terms that express the concept of electronic health (e-health). Highlights include precision of retrieved information; shift in terminology; and queries using the Pub Med…

  1. Online Piracy, Anonymity and Social Change – Deviance Through Innovation

    OpenAIRE

    Larsson, Stefan; Svensson, Måns; Kaminski, Marcin

    2012-01-01

    This article analyses current trends in the use of anonymity services among younger Swedes (15-25) and focuses on individuals engaging in illegal file sharing in order to better understand the rationale behind both file sharing as well as online anonymity, especially in relation to enforcement of copyright. By comparing the findings of a survey conducted on three different occasions (early 2009, late 2009 and early 2012), we measure the fluctuations in the use of anonymity services among appr...

  2. Secure Electronic Cash Scheme with Anonymity Revocation

    Directory of Open Access Journals (Sweden)

    Baoyuan Kang

    2016-01-01

    Full Text Available In a popular electronic cash scheme, there are three participants: the bank, the customer, and the merchant. First, a customer opens an account in a bank. Then, he withdraws an e-cash from his account and pays it to a merchant. After checking the electronic cash’s validity, the merchant accepts it and deposits it to the bank. There are a number of requirements for an electronic cash scheme, such as, anonymity, unforgeability, unreusability, divisibility, transferability, and portability. Anonymity property of electronic cash schemes can ensure the privacy of payers. However, this anonymity property is easily abused by criminals. In 2011, Chen et al. proposed a novel electronic cash system with trustee-based anonymity revocation from pairing. On demand, the trustee can disclose the identity for e-cash. But, in this paper we point out that Chen et al.’s scheme is subjected to some drawbacks. To contribute secure electronic cash schemes, we propose a new offline electronic cash scheme with anonymity revocation. We also provide the formally security proofs of the unlinkability and unforgeability. Furthermore, the proposed scheme ensures the property of avoiding merchant frauds.

  3. Efficient Query Rewrite for Structured Web Queries

    OpenAIRE

    Gollapudi, Sreenivas; Ieong, Samuel; Ntoulas, Alexandros; Paparizos, Stelios

    2011-01-01

    Web search engines and specialized online verticals are increasingly incorporating results from structured data sources to answer semantically rich user queries. For example, the query \\WebQuery{Samsung 50 inch led tv} can be answered using information from a table of television data. However, the users are not domain experts and quite often enter values that do not match precisely the underlying data. Samsung makes 46- or 55- inch led tvs, but not 50-inch ones. So a literal execution of the ...

  4. 基于PMI属性证书的匿名认证方案%Anonymous Authentication Scheme based-on AC of PMI

    Institute of Scientific and Technical Information of China (English)

    贺靖靖; 刘景森; 史强

    2013-01-01

      随着计算机网络迅速发展,网络交易也越来越普遍,然而在交易过程中,用户身份认证,访问控制及其授权管理成为系统关注的焦点。与此同时,人们对自己的隐私信息更为关注,用户希望通过匿名的方式访问资源。因此,如何实现用户对资源的匿名访问,是一个需要解决的问题。提出了一个基于PMI属性证书的匿名认证方案,实现了对资源的匿名访问。理论分析证明,该方案具有安全性、匿名性和不关联性,可追踪性。%With the rapid development of the computer network,the network transaction is becoming more and more popular, however, in the process of transaction user authentication, access control and its authorized management has become the focus of the system.At the same time, people pay more attention on their own privacy information; users want to access resources through anonymous way. Therefore, how to realize the anonymous access resources is a problem to be solved. This paper proposes a system which based on PMI’ s attribute certificates to realize the anonymous access. Theoretical analysis shows that this solution provides the security, anonymity and no relevance,traceability.

  5. 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

  6. 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...

  7. 基于隐私决策度的改进k-匿名算法%Improved Algorithm of k-anonymity Based on Degree of Privacy Preservation

    Institute of Scientific and Technical Information of China (English)

    申艳光; 闫晶星; 刘永红; 郭高尚

    2015-01-01

    现有的匿名化隐私保护技术在进行数据发布和数据共享前对于敏感属性的个性化隐私保护的支持存在不足,为了实现更为合理的个性化隐私保护,结合粒计算粗糙集理论和k-匿名理论的最新研究成果,针对电子商务中隐私保护个性化决策选择度的不同,从粒化角度出发,提出一种基于隐私决策度的改进k-匿名算法。经实验验证,该算法更好的实现了隐私保护的个性化,同时其隐私保护精度方面优于已有的p-Sensitive k-匿名算法。%In the existing anonymous privacy protection technology, there is a shortage of personalized privacy protection support for sensitive attributes before data release and sharing. In order to achieve more reasonable personalized privacy preservation and improve the precision of privacy preservation, this paper reviewed the latest researches in granular computing theory, rough set theory and k-anonymity theory, and presented an improved algorithm of k-anonymity based on the personalized decision degree of privacy preservation, in view of different personalized granularity decision selectivity of privacy preservation in E-business.The experimental results show that the novel algorithm can achieve privacy preservation with more reasonable personalization, and its accuracy of privacy preservation is superior to p-sensitive k-anonymity algorithm.

  8. 基于匿名化处理的报警关联分析技术研究%Study of alert correlation analysis technique based on anonymization

    Institute of Scientific and Technical Information of China (English)

    廖传谱; 连一峰

    2009-01-01

    Data generated by security systems may include sensitive information that data owners do not want to disclose or share with others.Therefore, efficient anonymization of the alert data containing privacy is necessary before they are shared and made correlation analysis.Anonymization of the original alerts containing privacy is dealt with by using concept hierarchy in this paper,on the basis of which the correlation analysis of anonymized alerts is carried out with altered probabilistic similarity based approaches.The result of experiments proves effective correlation approaches fit with anonymized alerts.%由安全系统产生的数据可能会包含一些比较敏感的信息,而这些敏感的信息又是数据拥有者不愿意公开或与别人共享的.因此.为了保持报警数据的隐私和可用性,需要对含有隐私的报警数据在被共享和关联分析之前进行有效的匿名化处理.利用概念层次对含有隐私的原始报警进行匿名化处理,在此基础上采用改进后的基于概率相似度的关联方法对匿名后的报警进行关联分析.实验结果表明,所采取的针对匿名报警的关联方法是有效的.

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

    DEFF Research Database (Denmark)

    Herrmann, Janne Rothmar

    2013-01-01

    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...... 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...

  10. Anonymous Authentication Scheme Based on Role Model of PMI%基于PMI角色模型的匿名认证方案

    Institute of Scientific and Technical Information of China (English)

    贺靖靖; 刘景森; 史强; 傅慧明

    2012-01-01

    隐私保护是当前网络应用中最受关注的问题之一,越来越多的用户希望加强隐私保护,在不泄露个人敏感信息的情况下实现资源访问.针对匿名访问控制提出了一种基于PKI/PMI证书的认证方案,即在用户和服务提供者之间引入可信第三方,利用角色说明属性证书RS-AC和角色分配属性证书RA-AC,实现匿名认证.理论分析证明,该方案具有安全性、匿名性和不关联性.%Nowadays,the privacy protection is one of the most concerned problems. More and more users want to strengthen their own privacy preservation and hope that they can access the resources without providing personal sensitive informations. An anonymous access control scheme is proposed which is based on PKI/PMI certificates. The trusted third party is introduced between users and the service provider. The role stated-attribute certificate(RS-AC) and role assigned attribute certificate(RA-AC) are used to implement the anonymous authentication. Theoretical analysis shows that this solution provides the security,anonymity and no relevance.

  11. The Query-commit Problem

    CERN Document Server

    Molinaro, Marco

    2011-01-01

    In the query-commit problem we are given a graph where edges have distinct probabilities of existing. It is possible to query the edges of the graph, and if the queried edge exists then its endpoints are irrevocably matched. The goal is to find a querying strategy which maximizes the expected size of the matching obtained. This stochastic matching setup is motivated by applications in kidney exchanges and online dating. In this paper we address the query-commit problem from both theoretical and experimental perspectives. First, we show that a simple class of edges can be queried without compromising the optimality of the strategy. This property is then used to obtain in polynomial time an optimal querying strategy when the input graph is sparse. Next we turn our attentions to the kidney exchange application, focusing on instances modeled over real data from existing exchange programs. We prove that, as the number of nodes grows, almost every instance admits a strategy which matches almost all nodes. This resu...

  12. 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.

  13. Research of Query Translation on Deep Web%Deep Web搜索中查询转换的研究

    Institute of Scientific and Technical Information of China (English)

    邵秀丽; 李云龙; 张文龙

    2012-01-01

    The mapping mechanism of query translation has been advanced, which is based on synonymous attributes and group attributes. The problem of how to realize the more accurate comprehensive mapping from the source query string to the target query string has been solved. The query substring to each source site for the realization of retrieval has been provided, the solution of this paper has been applied to 20 representative Deep Web sites which are selected from domestic books area, and the Deep Web search to these sites* book information is implemented.%基于同义属性和成组属性给出了查询转换映射机制,解决了如何从源查询串到目标查询串的较为准确的映射,实现了检索对应各源网址的转换查询子串,相应的方案应用于国内20个代表性的图书领域的DeepWeb站点,较好地实现了对这些站点的Deep Web图书信息的搜索.

  14. Intelligent query by humming system based on score level fusion of multiple classifiers

    Science.gov (United States)

    Pyo Nam, Gi; Thu Trang Luong, Thi; Ha Nam, Hyun; Ryoung Park, Kang; Park, Sung-Joo

    2011-12-01

    Recently, the necessity for content-based music retrieval that can return results even if a user does not know information such as the title or singer has increased. Query-by-humming (QBH) systems have been introduced to address this need, as they allow the user to simply hum snatches of the tune to find the right song. Even though there have been many studies on QBH, few have combined multiple classifiers based on various fusion methods. Here we propose a new QBH system based on the score level fusion of multiple classifiers. This research is novel in the following three respects: three local classifiers [quantized binary (QB) code-based linear scaling (LS), pitch-based dynamic time warping (DTW), and LS] are employed; local maximum and minimum point-based LS and pitch distribution feature-based LS are used as global classifiers; and the combination of local and global classifiers based on the score level fusion by the PRODUCT rule is used to achieve enhanced matching accuracy. Experimental results with the 2006 MIREX QBSH and 2009 MIR-QBSH corpus databases show that the performance of the proposed method is better than that of single classifier and other fusion methods.

  15. Intelligent query by humming system based on score level fusion of multiple classifiers

    Directory of Open Access Journals (Sweden)

    Park Sung-Joo

    2011-01-01

    Full Text Available Abstract Recently, the necessity for content-based music retrieval that can return results even if a user does not know information such as the title or singer has increased. Query-by-humming (QBH systems have been introduced to address this need, as they allow the user to simply hum snatches of the tune to find the right song. Even though there have been many studies on QBH, few have combined multiple classifiers based on various fusion methods. Here we propose a new QBH system based on the score level fusion of multiple classifiers. This research is novel in the following three respects: three local classifiers [quantized binary (QB code-based linear scaling (LS, pitch-based dynamic time warping (DTW, and LS] are employed; local maximum and minimum point-based LS and pitch distribution feature-based LS are used as global classifiers; and the combination of local and global classifiers based on the score level fusion by the PRODUCT rule is used to achieve enhanced matching accuracy. Experimental results with the 2006 MIREX QBSH and 2009 MIR-QBSH corpus databases show that the performance of the proposed method is better than that of single classifier and other fusion methods.

  16. 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.

  17. A peer-to-peer music sharing system based on query-by-humming

    Science.gov (United States)

    Wang, Jianrong; Chang, Xinglong; Zhao, Zheng; Zhang, Yebin; Shi, Qingwei

    2007-09-01

    Today, the main traffic in peer-to-peer (P2P) network is still multimedia files including large numbers of music files. The study of Music Information Retrieval (MIR) brings out many encouraging achievements in music search area. Nevertheless, the research of music search based on MIR in P2P network is still insufficient. Query by Humming (QBH) is one MIR technology studied for years. In this paper, we present a server based P2P music sharing system which is based on QBH and integrated with a Hierarchical Index Structure (HIS) to enhance the relation between surface data and potential information. HIS automatically evolving depends on the music related items carried by each peer such as midi files, lyrics and so forth. Instead of adding large amount of redundancy, the system generates a bit of index for multiple search input which improves the traditional keyword-based text search mode largely. When network bandwidth, speed, etc. are no longer a bottleneck of internet serve, the accessibility and accuracy of information provided by internet are being more concerned by end users.

  18. QuerySpaces on Hadoop for the ATLAS EventIndex

    CERN Document Server

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

    2015-01-01

    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 optimisation. Detailed description 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.

  19. 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.

  20. Co-occurrence Relation of DNS Queries Based Research on Botnet Activities

    Directory of Open Access Journals (Sweden)

    Zhiwen Wang

    2012-05-01

    Full Text Available As a new platform for launching attacks collectively, botnets have been considered as the leading security threat to the Internet in the literature. Previous works focus on how to detect zombies via some of the behavioral patterns of botnets. However, it’s an important and challenging task to track the network activities of the zombies so as to have an insight into the global view of “what those zombies do” besides “who those zombies are” since it’s an exclusively nature of botnets to stay stealthy when conducting various malicious activities as long as possible. In this paper, an improved approach is proposed to handle this new problem based on co-occurrence relation of DNS queries with full consideration of the spatial and temporal properties of botnet activities. The approach excludes noise made by NAT, and distinguishes domains with co-occurrence relation by botnet activities from them by normal user activation, according to the spatial dimensions and time dimensions. Then, we validate the approach using DNS traffic in real network. The experimental result shows it can eliminate the NAT interference, significantly reduce the amount of data and improve the discovery of unknown botnet domain exceptionalness, we analysis main factors whish impact the approach, and then proposed treatment strategies correspondingly.

  1. An Algorithm for Solving Natural Language Query Execution Problems on Relational Databases

    Directory of Open Access Journals (Sweden)

    Enikuomehin A. O

    2012-10-01

    Full Text Available There continues to be an increased need for non-experts interaction with databases. This is essential in their quest to make appropriate business decisions. Researchers have, over the years, continued to find a methodology that bridges the gap that exist between information need and users satisfaction. This has been the core in studies related to natural language information retrieval. In this paper, we understudy the existing methodology and develop a model to extend the proposition of (a Bhardwaj et al where a MAPPER was developed and implemented on student database and (b Nihalani et al. where an integrated interface was used on relational databases. We present a time saving executable algorithm that satisfies needed conditions required to retrieve results of natural language based queries from relational databases. Results of the experiment shows that the performance index of the algorithm is satisfactory and can be improved upon increasing the metadata table of the relational database. This is a sharp diversion from the keyword based search that has dominated most commercial databases in use today. The implementation was deployed in PHP and the retrieval time has compared favorably with earlier deployed models. We further propose the extension of this work in the areas of inculcating some fuzzy constraints to handle uncertainty and ambiguity which are inherent in human natural language

  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...... \\leqslant f(n) \\leqslant Ö{log n} Unknown control sequence '\\leqslant'. A data structure is presented supporting insertions and deletions in worst case O(f(n)) time, predecessor queries in worst case O((logn)/f(n)) time and minimum and maximum queries in worst case constant time. The required space is O(n2w...

  3. 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

  4. Anonymous Web Browsing and Hosting

    Directory of Open Access Journals (Sweden)

    MANOJ KUMAR

    2013-02-01

    Full Text Available 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 how we can choose safe web hosting solutions and what the main functions are which provides more security over server data. With the browser security network security is also important which can be implemented using cryptography solutions, VPN and by implementing firewalls on the network. Hackers always try to steal our identity and data, they track our activities using the network application software’s and do harmful activities. So in this paper we described that how we can monitor them from security purposes.

  5. SPIN query tools for de-identified research on a humongous database.

    Science.gov (United States)

    McDonald, Clement J; Dexter, Paul; Schadow, Gunther; Chueh, Henry C; Abernathy, Greg; Hook, John; Blevins, Lonnie; Overhage, J Marc; Berman, Jules J

    2005-01-01

    The Shared Pathology Informatics Network (SPIN), a research initiative of the National Cancer Institute, will allow for the retrieval of more than 4 million pathology reports and specimens. In this paper, we describe the special query tool as developed for the Indianapolis/Regenstrief SPIN node, integrated into the ever-expanding Indiana Network for Patient care (INPC). This query tool allows for the retrieval of de-identified data sets using complex logic, auto-coded final diagnoses, and intrinsically supports multiple types of statistical analyses. The new SPIN/INPC database represents a new generation of the Regenstrief Medical Record system - a centralized, but federated system of repositories. PMID:16779093

  6. Multi-Classifier Based on a Query-by-Singing/Humming System

    Directory of Open Access Journals (Sweden)

    Gi Pyo Nam

    2015-06-01

    Full Text Available With the increase in the number of music files on various devices, it can be difficult to locate a desired file, especially when the title of the song or the name of the singer is not known. We propose a new query-by-singing/humming (QbSH system that can find music files that match what the user is singing or humming. This research is novel in the following three ways: first, the Fourier descriptor (FD method is proposed as the first classifier; it transforms the humming or music waveform into the frequency domain. Second, quantized dynamic time warping (QDTW using symmetrical search space and quantized linear scaling (QLS are used as the second and third classifiers, respectively, which increase the accuracy of the QbSH system compared to the conventional DTW and LS methods. Third, five classifiers, which include the three already mentioned along with the conventional DTW using symmetrical search space and LS methods, are combined using score level fusion, which further enhances performance. Experimental results with the 2009 MIR-QbSH corpus and the AFA MIDI 100 databases show that the proposed method outperforms those using a single classifier and other fusion methods.

  7. A Mixed Anonymous System based on Tor%基于Tor的混合匿名转发系统

    Institute of Scientific and Technical Information of China (English)

    郑光; 薛质

    2011-01-01

    随着互联网应用的不断增加,人们对网络通信的保密性也越来越重视。Tor匿名通信系统具有低时延、数据加密传输,安全信道等优点,能够有效保护通信者的信息安全,目前正成为一种流行的匿名通信系统。但随着Tor系统使用和研究的人增多,Tor系统本身的一些缺陷给其安全带来了隐患。为此,在现有Tor系统分析的基础上,文中提出了一种安全新型的混合匿名转发系统H—Tor。该系统由Hordes和Tor有效级联组合,充分发挥了两者的优势。分析表明,H—Tor可以抵御通信流攻击和端对端攻击,有效保护通信者的匿名安全。%With the continuous increase of lnternet applications, people pay much attention to the confidentiality of network communications. Tor anonymous communication system, with low latency, data eneryption transmission, secure channel, etc., could effectively protect the information security of the correspondents, and thus becomes a popular anonymous communication system. However, with in-depth study wide use of the Tor system, Tor presents some defects in security risks. Currently, a new system called H-Tor is proposed upon the analysis of Tor. The system combines Hordes with Tor and gives full play to their advantages. Analysis shows that the H-Tor integration can effectively protect the anonymity of the correspondents.

  8. 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.

  9. Provenance for Aggregate Queries

    OpenAIRE

    Yael Amsterdamer; Daniel Deutch; Val Tannen

    2011-01-01

    We study in this paper provenance information for queries with aggregation. Provenance information was studied in the context of various query languages that do not allow for aggregation, and recent work has suggested to capture provenance by annotating the different database tuples with elements of a commutative semiring and propagating the annotations through query evaluation. We show that aggregate queries pose novel challenges rendering this approach inapplicable. Consequently, we propose...

  10. An Efficient Query Rewriting Approach for Web Cached Data Management

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    With the internet development, querying data on the Web is an attention problem of involving information from distributed, and often dynamically, related Web sources. Basically, some sub-queries can be effectively cached from previous queries or materialized views in order to achieve a better query performance based on the notion of rewriting queries. In this paper, we propose a novel query-rewriting model, called Hierarchical Query Tree, for representing Web queries. Hierarchical Query Tree is a labeled tree that is suitable for representing the inherent hierarchy feature of data on the Web. Based on Hierarchical Query Tree, we use case-based approach to determine what the query results should be. The definitions of queries and query results are both represented as labeled trees. Thus, we can use the same model for representing cases and the medium query results can also be dynamically updated by the user queries. We show that our case-based method can be used to answer a new query based on the combination of previous queries, including changes of requirements and various information sources.

  11. Learning semantic query suggestions

    NARCIS (Netherlands)

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

    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 faci

  12. Efficient Query Rewrite for Structured Web Queries

    CERN Document Server

    Gollapudi, Sreenivas; Ntoulas, Alexandros; Paparizos, Stelios

    2011-01-01

    Web search engines and specialized online verticals are increasingly incorporating results from structured data sources to answer semantically rich user queries. For example, the query \\WebQuery{Samsung 50 inch led tv} can be answered using information from a table of television data. However, the users are not domain experts and quite often enter values that do not match precisely the underlying data. Samsung makes 46- or 55- inch led tvs, but not 50-inch ones. So a literal execution of the above mentioned query will return zero results. For optimal user experience, a search engine would prefer to return at least a minimum number of results as close to the original query as possible. Furthermore, due to typical fast retrieval speeds in web-search, a search engine query execution is time-bound. In this paper, we address these challenges by proposing algorithms that rewrite the user query in a principled manner, surfacing at least the required number of results while satisfying the low-latency constraint. We f...

  13. 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…

  14. 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.

  15. 采用RDF的查询扩展研究%ON QUERY EXTENSION USING RDF

    Institute of Scientific and Technical Information of China (English)

    姜旭; 张波

    2011-01-01

    由于传统的P2P查询处理将用户查询作为独立的关键字对待,只考虑其字面符号意义而不考虑其语义.因此,用户的查询需求往往得不到真实的体现.基于本体的P2P资源匹配使用本体对网络资源进行了描述,在很大程度上反映了资源的语义,然而仍需要对查询请求进行语义扩展才适合在资源的本体中进行查询处理.使用RDF三元组描述用户请求,并扩展其语义表达能力,分析本体中概念间的上下位关系,对查询请求进行语义扩展,扩展后的查询适合于利用本体进行查询匹配.分析表明,这种扩展是有效的合理的.%Traditional P2P query processing method regards user's query as independent key words, considering just its literal meaning without digging its semantics, therefore user's query requirement can't be comprehended rightly. Ontology-based P2P matchmaking depicts network resources using ontology, though the semantics of resource has been greatly exposed, but it still need proper query extension in semantics to fit for matchmaking in resource ontology. In this paper we use RDF triple to describe query, and extend its semantic expression ability, analyse the inheriting relationship between concepts in ontology to extend the query semantically; the extended query is more suitable for matchmaking with ontology. Analysis indicates that the extension is more effective and reasonable.

  16. Efficient caching for constrained skyline queries

    DEFF Research Database (Denmark)

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

    2015-01-01

    Constrained skyline queries retrieve all points that optimize some user’s preferences subject to orthogonal range constraints, but at significant computational cost. This paper is the first to propose caching to improve constrained skyline query response time. Because arbitrary range constraints...... are unlikely to match a cached query exactly, our proposed method identifies and exploits similar cached queries to reduce the computational overhead of subsequent ones. We consider interactive users posing a string of similar queries and show how these can be classified into four cases based on how...... they overlap cached queries. For each we present a specialized solution. For the general case of independent users, we introduce the Missing Points Region (MPR), that minimizes disk reads, and an approximation of the MPR. An extensive experimental evaluation reveals that the querying for an (approximate) MPR...

  17. 本体的查询与推理研究%Research on Ontology Querying and Inference

    Institute of Scientific and Technical Information of China (English)

    王晓慧; 罗军; 余淑良

    2012-01-01

    Nowadays,computer network is widely used in various aspects of life. But searching for what people need from the mass information has a lot of questions. Consequently,the concept of ontology has appeared. And then ontology querying and inference is the important component of the application based on ontology. The purposes of this research are to make the knowledge to the fullest expression and querying the information more accurate and complete. Firstly, introduced the concept of ontology and constructed an ontology model. Then used ontology query language,SPARQL,to query me existed model. And also used SWRL to extend the semantic rules. Finally,introduced lena with which obtained more knowledge by reasoning on the model. Thus concluded,in the process of querying and inference with SPARQL and Jena,inference could develop the ability of querying,and the rules were the key to increase the power of inference.%现今,计算机网络被广泛应用于生活的方方面面,而从海量的信息中搜寻出人们所需要的还存在诸多问题,于是产生了本体的概念.而本体的查询和推理是基于本体的应用中重要的组成部分,研究的目的是为了使知识得以充分表达并且对信息的查询更加精确、完备.首先介绍了本体的概念并建立本体模型,然后用本体查询语言SPARQL对已有模型进行查询并用SWRL对模型进行语义规则的扩充;最后介绍了Jena,并对本体模型进行推理,由此获得了更多知识.结论就是,在利用SPARQL和Jena进行查询与推理的过程中,推理将提高查询能力,而规则是提高推理能力的关键.

  18. 基于URL主题的查询分类方法%Query Classification Based on URL Topic

    Institute of Scientific and Technical Information of China (English)

    张宇; 宋巍; 刘挺; 李生

    2012-01-01

    互联网上很多资源蕴含人类群体智慧.分类网站目录人工地对网站按照主题进行组织.基于网站目录中具有主题标注的URL设计URL主题分类器,结合伪相关反馈技术以及搜索引擎查询日志,提出了自动、快速、有效的查询主题分类方法.具体地,方法为2种策略的结合.策略1通过计算搜索结果中URL的主题分布预测查询主题,策略2基于查询日志点击关系,利用具有主题标注的URL,对查询进行标注获取数据并训练统计分类器预测查询主题.实验表明,方法可获得比当前最好算法更好的准确率,更好的在线处理效率并且可基于查询日志自动获取训练数据,具有良好的可扩展性.%Many online resources contain crowd intelligence. Categorized website directory is one kind of resources constructed and maintained manually. It aims to organize websites according to a topical taxonomy. Based on the URLs with topical labels in website directory, a URL topical classifier could be designed. Together with pseudo relevance feedback technique and search engine query logs, an automatic, fast and efficient query topical classification method is proposed. In detail, the method combines two strategies. Strategy-1 is to predict a query's topic by computing the topic distribution among the returned URLs of a search system. Strategy-2 is to train a statistical classifier using the automatically labeled queries in query logs based on the topic of clicked URLs. The experimental results show that our method can achieve better precision compared with a state of the art algorithm and is more efficient for online processing. It has good scalability and can construct large scale training data from query logs automatically.

  19. A novel informatics concept for high-throughput shotgun lipidomics based on the molecular fragmentation query language

    OpenAIRE

    Herzog, Ronny; Schwudke, Dominik; Schuhmann, Kai; Sampaio, Julio L; Bornstein, Stefan R; Schroeder, Michael; Shevchenko, Andrej

    2011-01-01

    Shotgun lipidome profiling relies on direct mass spectrometric analysis of total lipid extracts from cells, tissues or organisms and is a powerful tool to elucidate the molecular composition of lipidomes. We present a novel informatics concept of the molecular fragmentation query language implemented within the LipidXplorer open source software kit that supports accurate quantification of individual species of any ionizable lipid class in shotgun spectra acquired on any mass spectrometry plat...

  20. P-Sensitive K-Anonymity with Generalization Constraints

    Directory of Open Access Journals (Sweden)

    Alina Campan

    2010-08-01

    Full Text Available Numerous privacy models based on the k-anonymity property and extending the k-anonymity model have been introduced in the last few years in data privacy research: l-diversity, p-sensitive k-anonymity, (a, k anonymity, t-closeness, etc. While differing in their methods and quality of their results, they all focus first on masking the data, and then protecting the quality of the data as a whole. We consider a new approach, where requirements on the amount of distortion allowed on the initial data are imposed in order to preserve its usefulness. Our approach consists of specifying quasiidentifiers' generalization constraints, and achieving p-sensitive k-anonymity within the imposed constraints. We think that limiting the amount of allowed generalization when masking microdata is indispensable for real life datasets and applications. In this paper, the constrained p-sensitive k-anonymity model is introduced and an algorithm for generating constrained p-sensitive k-anonymous microdata is presented. Our experiments have shown that the proposed algorithm is comparable with existing algorithms used for generating p-sensitive k-anonymity with respect to the results' quality, and obviously the obtained masked microdata complies with the generalization constraints as indicated by the user.

  1. Provenance Query Protocol

    OpenAIRE

    Miles, S.; Moreau, L; Groth, P; Tan, V.; Munroe, S; Jiang, Sheng

    2006-01-01

    A related document defines schemas to be used for documentation about the execution of a process. It also defines the provenance of a data item as the process that led to that item. A provenance query is a query for the provenance of a data item and the results of such a query is documentation of the process that led to the item. In this document, we specify a protocol by which a querying actor and provenance store can communicate in performing a provenance query. This primarily takes the for...

  2. Automatic Control of Configuration of Web Anonymization

    Directory of Open Access Journals (Sweden)

    Tomas Sochor

    2013-01-01

    Full Text Available Anonymization of the Internet traffic usually hides details about the request originator from the target server. Such a disguise might be required in some situations, especially in the case of web browsing. Although the web traffic anonymization is not a part of the http specification, it could be achieved using a certain extra tool. Significant deceleration of anonymized traffic compared to normal traffic is inevitable but it can be controlled in some cases as this article suggests. The results presented here focus on measuring the parameters of such deceleration in terms of response time, transmission speed and latency and proposing the way how to control it. This study focuses on TOR primarily because recent studies have concluded that other tools (like I2P and JAP provide worse service. Sets of 14 file locations and 30 web pages have been formed and the latency, response time and transmission speed during the page or file download were measured repeatedly both with TOR active in various configurations and without TOR. The main result presented here comprises several ways how to improve the TOR anonymization efficiency and the proposal for its automatic control. In spite of the fact that efficiency still remains too low compared to normal web traffic for ordinary use, its automatic control could make TOR a useful tool in special cases.

  3. Probabilistic Adaptive Anonymous Authentication in Vehicular Networks

    Institute of Scientific and Technical Information of China (English)

    Yong Xi; Ke-Wei Sha; Wei-Song Shi; Loren Schwiebert; Tao Zhang

    2008-01-01

    Vehicular networks have attracted extensive attention in recent years for their promises in improving safety and enabling other value-added services. Most previous work focuses on designing the media access and physical layer protocols.Privacy issues in vehicular systems have not been well addressed. We argue that privacy is a user-specific concept, and a good privacy protection mechanism should allow users to select the levels of privacy they wish to have. To address this requirement, we propose an adaptive anonymous authentication mechanism that can trade off the anonymity level with computational and communication overheads (resource usage). This mechanism, to our knowledge, is the first effort on adaptive anonymous authentication. The resources used by our protocol are few. A high traffic volume of 2000 vehicles per hour consumes about 60kbps bandwidth, which is less than one percent of the bandwidth of DSRC (Dedicated Short Range Communications). By using adaptive anonymity, the protocol response time can further be improved 2~4 times with lessthan 20% bandwidth overheads.

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

    Directory of Open Access Journals (Sweden)

    Taboada María

    2012-07-01

    Full Text Available Abstract Background 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. Methods 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. Results 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. Conclusions This work demonstrates how semantic web technologies can be used to support

  5. KDS-CM: A Cache Mechanism Based on Top-K Data Source for Deep Web Query

    Institute of Scientific and Technical Information of China (English)

    KOU Yue; SHEN Derong; YU Ge; LI Dong; NIE Tiezheng

    2007-01-01

    Caching is an important technique to enhance the efficiency of query processing. Unfortunately, traditional caching mechanisms are not efficient for deep Web because of storage space and dynamic maintenance limitations. In this paper, we present on providing a cache mechanism based on Top-K data source (KDS-CM) instead of result records for deep Web query.By integrating techniques from IR and Top-K, a data reorganization strategy is presented to model KDS-CM. Also some measures about cache management and optimization are proposed to improve the performances of cache effectively. Experimental results show the benefits of KDS-CM in execution cost and dynamic maintenance when compared with various alternate strategies.

  6. “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.

  7. Distributed Top-k Queries in E-commerce Environment

    Institute of Scientific and Technical Information of China (English)

    JiangZhan; YiqingSong; HaixiaZhang

    2004-01-01

    This paper focus on how to make distributed top-k query in e-commerce environment through web service. We first give the query process in such environment, then we present an algorithms for processing such queries, which based on the query model we defined. Experimental results show that the algorithms is efficient.

  8. Practical Quantum Private Database Queries Based on Passive Round-Robin Differential Phase-shift Quantum Key Distribution

    Science.gov (United States)

    Li, Jian; Yang, Yu-Guang; Chen, Xiu-Bo; Zhou, Yi-Hua; Shi, Wei-Min

    2016-01-01

    A novel quantum private database query protocol is proposed, based on passive round-robin differential phase-shift quantum key distribution. Compared with previous quantum private database query protocols, the present protocol has the following unique merits: (i) the user Alice can obtain one and only one key bit so that both the efficiency and security of the present protocol can be ensured, and (ii) it does not require to change the length difference of the two arms in a Mach-Zehnder interferometer and just chooses two pulses passively to interfere with so that it is much simpler and more practical. The present protocol is also proved to be secure in terms of the user security and database security. PMID:27539654

  9. Moving Spatial Keyword Queries

    DEFF Research Database (Denmark)

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

    2013-01-01

    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...... zones, we study analytically the expected area of a safe zone, which indicates on average for how long a safe zone remains valid, and we study the expected number of influence objects needed to define a safe zone, which gives an estimate of the average communication cost. The analytical modeling...

  10. Certain Investigations on Query processing related issues in Mobile Computing Platforms for Large Datasets

    Directory of Open Access Journals (Sweden)

    Andamuthu Palanisamy

    2012-11-01

    Full Text Available Applications in real time environment demands interactions from different devices both fixed and mobile devices in a seamless manner. The users interacting are in different geographic environments. The datasets are of different nature and allows for interaction across users in different levels with more levels of constraints. This in turn leads to different directions for addressing the issues in mobile computing. The queries from users are also complex and involve joins. The data residing also leads to issues of data management and prioritization of requests in communication. The technology enabled devices are also improving with processors and different platforms like HTML5 to address the existing issues. This paper presents a detailed survey of different issues in query processing in mobile environment. The solutions are also presented for the existing issues at the end of the paper.

  11. Distributed location-based query processing on large volumes of moving items

    Institute of Scientific and Technical Information of China (English)

    JEON Se-gil; LEE Chung-woo; NAH Yunmook; KIM Moon-hae; HAN Ki-joon

    2004-01-01

    Recently, new techniques to efficiently manage current and past location information of moving objects have received significant interests in the area of moving object databases and location-based service systems. In this paper, we exploit query processing schemes for location management systems, which consist of multiple data processing nodes to handle massive volume of moving objects such as cellular phone users.To show the usefulness of the proposed schemes, some experimental results showing performance factors regarding distributed query processing are explained. In our experiments, we use two kinds of data set: one is generated by the extended GSTD simulator and another is generated by the real-time data generator which generates location sensing reports of various types of users having different movement patterns.

  12. Improving Security Architecture of Anonymous Wireless Mesh Networks

    DEFF Research Database (Denmark)

    Banoth, Rajkumar

    2012-01-01

    As users of networks increasingly aware of their privacy needs, the importance of anonymity is gaining popularity. The reason behind it is that anonymity can hide the actual identity of end users while allowing their to access services of network or web site. More over they are allowed to do so...... without being traced. This usage is prevailing in P2P systems and also payment based networks like e-cash. Achieving anonymity and being able to trace misbehaving users are the two conflicting requirements. This paper proposes a security architecture that is aimed at providing complete anonymity to honest...... users while tracing misbehaving users thus resolving the conflict between anonymity and traceability requirements. In addition to these, this paper also focuses on basic security requirements such as nonrepudiation, data integrity, confidentiality, and authentication. The empirical results revealed that...

  13. Robust Quantum Private Queries

    Science.gov (United States)

    Wang, Tian-Yin; Wang, Shu-Yu; Ma, Jian-Feng

    2016-07-01

    We propose a new quantum private query protocol with the technique of decoherence-free states, which is a theoretical study of how decoherence-free states can be used for the protection of quantum information in such a protocol. This protocol can solve the noise problem that will make the user obtain a wrong answer and hence give rise to a bad influence on the reputation of the database provider. Furthermore, this protocol is also flexible, loss-resistant and easily generalized to a large database similar to the previous works.

  14. An Efficient Temporal Query Search for Time Sensitive Queries

    Directory of Open Access Journals (Sweden)

    Mani. G

    2013-11-01

    Full Text Available Time Stamp is an important magnitude for document relevance for a large number of searches, such as over blogs and news archives. Research on searching over such collections has largely focused on locating topically similar documents for a query. Unfortunately, topic similarity alone is not always sufficient for document ranking. In this paper we presented an efficient method for processing time-sensitive queries over a news archive, with techniques for identifying important time periods for a query. This work demonstrates the integrating time in the retrieval task can improve the quality of the retrieval results, and motivates further research in the area. Currently, we rely on the publication time of the documents to locate time periods of interest. However, a document published at a later date (e.g., a review article, summarizing an event may also be relevant. In this paper the research direction is to introduce time-based diversity in query results by grouping the results into clusters of relevant time ranges, enabling users to be aware of and interact with time information when examining the query results

  15. Research on Semantic Data Query Method Based on Hadoop%基于Hadoop平台的语义数据查询策略研究

    Institute of Scientific and Technical Information of China (English)

    胡志刚; 景冬梅; 陈柏林; 杨柳

    2016-01-01

    In order to achieve the efficient query for large-scale RDF (resource description framework) data, this paper analyzes the storage method of RDF triples in HBase and designs a two-stage query strategy for large-scale RDF data based on MapReduce, which is divided into two stages:the SPARQL (simple protocol and RDF query language) pre-treatment stage and the distributed query execution stage. In the SPARQL pretreatment stage, an SPARQL query classi-fication algorithm—JOVR (join on variable relation) is implemented, which determines the join order of connection variables by calculating the correlation between the variables in an SPARQL query statement, then the join between SPARQL clauses is divided into the minimum number of MapReduce jobs according to the connection variables. The distributed query execution stage accomplishes large-scale RDF data query concurrently based on MapRdecue jobs from SPARQL pretreatment stage. The experimental results on the LUMB benchmark set indicate that JOVR can query large-scale RDF data efficiently with good stability and scalability.%为了实现对海量RDF(resource description framework)数据的高效查询,研究了RDF三元组在分布式数据库HBase中的存储方法,基于MapReduce设计了海量RDF数据的两阶段查询策略,将查询分为SPARQL (simple protocol and RDF query language)预处理阶段与分布式查询执行阶段。SPARQL预处理阶段设计实现了基于SPARQL变量关联度的查询划分算法JOVR(join on variable relation),通过计算SPARQL查询语句中变量的关联度确定连接变量的连接顺序,根据连接变量将SPARQL子句连接操作划分到最小数量的Map-Reduce任务中;分布式查询执行阶段执行SPARQL预处理阶段划分的MapReduce任务,实现对海量RDF数据的并行查询。在LUBM标准测试数据集中的实验表明,JOVR算法能够高效地实现对海量RDF数据的查询,并具有良好的稳定性与可扩展性。

  16. Implementation of Quantum Private Queries Using Nuclear Magnetic Resonance

    Institute of Scientific and Technical Information of China (English)

    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.

  17. 基于用户日志挖掘的查询扩展方法%A NEW QUERY EXPANSION METHOD BASED ON USER LOGS MINING

    Institute of Scientific and Technical Information of China (English)

    朱鲲鹏; 魏芳

    2012-01-01

    查询扩展可以有效地消除查询歧义,提高信息检索的准确率和召回率.通过挖掘用户日志中查询词和相关文档的连接关系,构造关联查询,并在此基础上提出一种从关联查询中提取查询扩展词的查询扩展方法.同时,还提出一种查询歧义的判别方法,该方法可以对查询词所表达的检索意图的模糊程度进行有效度量,也可以对查询词的检索性能进行预先估计.通过对查询歧义的度量来动态调整扩展词的长度,提高查询扩展模型的灵活性和适应能力.%Query expansion has long been suggested as an effective way to eliminate query ambiguity and improve the precision and recall rates of information retrieval. By mining relations among phrases and relative documents in user logs, the paper constructs related queries, based on which proposes a query expansion method to extract query expansion words from related queries. Meanwhile the paper introduces a method to measure the ambiguity of user queries, which can calculate the fuzzy degree of uses' search intentions and can estimate the performance of search sessions in advance. Trie query ambiguity measurement helps dynamically adjusting the number of expanded terms, so that the flexibility and adaptability of query expansion model is improved.

  18. DISTRIBUTED QUERY OPTIMIZATION

    Directory of Open Access Journals (Sweden)

    Nicoleta IACOB

    2010-12-01

    Full Text Available The need for the distributed systems has been determined by the type of business developed by companies with offices geographically distributed where the specific organizational structure promotes a decentralized business model. This paper describes the techniques and concepts of system architecture for distributed database management systems, followed by the presentation of implementation phases involved when dealing with the distributed queries across distributed systems. The goal of query optimization is to determine the most efficient way to execute a query in a distributed environment, by obtaining a lower system response time and also by minimizing the query execution time. For this, we will analyze the factors that influence the ways to execute a query and we will also review the available strategies to optimize the distributed query execution.

  19. Exploring features for automatic identification of news queries through query logs

    Institute of Scientific and Technical Information of China (English)

    Xiaojuan; ZHANG; Jian; LI

    2014-01-01

    Purpose:Existing researches of predicting queries with news intents have tried to extract the classification features from external knowledge bases,this paper tries to present how to apply features extracted from query logs for automatic identification of news queries without using any external resources.Design/methodology/approach:First,we manually labeled 1,220 news queries from Sogou.com.Based on the analysis of these queries,we then identified three features of news queries in terms of query content,time of query occurrence and user click behavior.Afterwards,we used 12 effective features proposed in literature as baseline and conducted experiments based on the support vector machine(SVM)classifier.Finally,we compared the impacts of the features used in this paper on the identification of news queries.Findings:Compared with baseline features,the F-score has been improved from 0.6414 to0.8368 after the use of three newly-identified features,among which the burst point(bst)was the most effective while predicting news queries.In addition,query expression(qes)was more useful than query terms,and among the click behavior-based features,news URL was the most effective one.Research limitations:Analyses based on features extracted from query logs might lead to produce limited results.Instead of short queries,the segmentation tool used in this study has been more widely applied for long texts.Practical implications:The research will be helpful for general-purpose search engines to address search intents for news events.Originality/value:Our approach provides a new and different perspective in recognizing queries with news intent without such large news corpora as blogs or Twitter.

  20. Social Indispensability in Spite of Temporal and Spatial Separation: Motivation Gains in a Sequential Task During Anonymous Cooperation on the Internet

    Directory of Open Access Journals (Sweden)

    Marion Wittchen

    2007-12-01

    Full Text Available Recent research has demonstrated motivation gains during synchronous group work compared to individual work when group members’ contribution was indispensable for the group’s success (e.g., Hertel, Kerr, & Messé, 2000, Hertel, Deter, & Konradt, 2003. The current study extends this earlier research (a by examining indispensability effects during sequential cooperation (temporal separation, and (b by exploring these effects under conditions of high anonymity on the Internet (spatial separation. A 2 (Internet vs. laboratory context x 3 (high vs. low vs. no impact of personal contribution for a group x 2 (individual vs. group trial design was used with the last factor measured within subjects (N = 231. Motivation was measured with a vigilance task that simulated an Internet travel agency selling package holidays according to incoming customer requests. During all trials, participants received contemporaneous feedback about their own performance. During the group trials, participants additionally received information about their partner’s alleged previous performance at this point of the trial, which suggested that the partner had always performed slightly better than the participant. As expected, both in the laboratory and the Internet setting, the highest motivation gains occurred when participants’ contribution to the group’s outcome was indispensable for the group. This finding provides evidence that motivation gains among inferior group members are possible even during sequential group work under highly anonymous conditions.

  1. 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...... 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....

  2. 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...

  3. Information Network Model Query Processing

    Science.gov (United States)

    Song, Xiaopu

    Information Networking Model (INM) [31] is a novel database model for real world objects and relationships management. It naturally and directly supports various kinds of static and dynamic relationships between objects. In INM, objects are networked through various natural and complex relationships. INM Query Language (INM-QL) [30] is designed to explore such information network, retrieve information about schema, instance, their attributes, relationships, and context-dependent information, and process query results in the user specified form. INM database management system has been implemented using Berkeley DB, and it supports INM-QL. This thesis is mainly focused on the implementation of the subsystem that is able to effectively and efficiently process INM-QL. The subsystem provides a lexical and syntactical analyzer of INM-QL, and it is able to choose appropriate evaluation strategies and index mechanism to process queries in INM-QL without the user's intervention. It also uses intermediate result structure to hold intermediate query result and other helping structures to reduce complexity of query processing.

  4. Learning Joint Query Interpretation and Response Ranking

    OpenAIRE

    Sawant, Uma; Chakrabarti, Soumen

    2012-01-01

    Thanks to information extraction and semantic Web efforts, search on unstructured text is increasingly refined using semantic annotations and structured knowledge bases. However, most users cannot become familiar with the schema of knowledge bases and ask structured queries. Interpreting free-format queries into a more structured representation is of much current interest. The dominant paradigm is to segment or partition query tokens by purpose (references to types, entities, attribute names,...

  5. Anonymity And Accountability In Web Based Transactions

    Directory of Open Access Journals (Sweden)

    H.Jayasree

    2012-04-01

    Full Text Available Decreased privacy is an unavoidable consequence in the drive to make the world a more secure, safer place, according to some analysts. In the on-line world, the conflict between privacy and security manifests itself in a debate between anonymity and accountability. Balance between Anonymity and Accountability is a major concern in web based transactions. The protection of users’ privacy when performing web-based transactions is an important factor in the acceptance and use of Internet and web services. There is a tremendous improvement in the automation of the way we pay for goods and services by the variety and growth of electronic banking services available to the consumers. Hence there is a need for the ultimate structure of the new electronic transaction system that has a substantial impact on the personal privacy as well as on the nature and extent of criminal use of E- transactions. This paper presents an approach for such structure.

  6. Oceanographic ontology-based spatial knowledge query

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The construction of oceanographic ontologies is fundamental to the "digital ocean". Therefore, on the basis of introduction of new concept of oceanographic ontology, an oceanographic ontology-based spatial knowledge query (OOBSKQ) method was proposed and developed. Because the method uses a natural language to describe query conditions and the query result is highly integrated knowledge,it can provide users with direct answers while hiding the complicated computation and reasoning processes, and achieves intelligent,automatic oceanographic spatial information query on the level of knowledge and semantics. A case study of resource and environmental application in bay has shown the implementation process of the method and its feasibility and usefulness.

  7. Querying moving objects detected by sensor networks

    CERN Document Server

    Bestehorn, Markus

    2012-01-01

    Declarative query interfaces to Sensor Networks (SN) have become a commodity. These interfaces allow access to SN deployed for collecting data using relational queries. However, SN are not confined to data collection, but may track object movement, e.g., wildlife observation or traffic monitoring. While rational approaches are well suited for data collection, research on ""Moving Object Databases"" (MOD) has shown that relational operators are unsuitable to express information needs on object movement, i.e., spatio-temporal queries. ""Querying Moving Objects Detected by Sensor Networks"" studi

  8. Privacy, anonymity and subjectivity in genomic research.

    Science.gov (United States)

    McGonigle, Ian; Shomron, Noam

    2016-01-01

    The use of non-anonymized human genome data is becoming increasingly popular in research. Here we review the proceedings of a special meeting on this topic that took place at European Molecular Biology Organization (EMBO) in December 2014. The main points discussed centered on how to achieve 'anonymity,' 'trust,' and 'protection of data' in relation to new genomic technologies and research. Following our report of this meeting, we also raise three further issues for future consideration: the harmonization of international law in relation to genetic data protection; the complex issues around the 'dividual' nature of genetic data; and the growing commercial value of personal data. In conclusion, we stress the importance of scientists working in the area of genomic research engaging in interdisciplinary collaborations with humanities and social science scholars and addressing these complicated issues. PMID:26763729

  9. Privacy, anonymity and subjectivity in genomic research.

    Science.gov (United States)

    McGonigle, Ian; Shomron, Noam

    2016-01-01

    The use of non-anonymized human genome data is becoming increasingly popular in research. Here we review the proceedings of a special meeting on this topic that took place at European Molecular Biology Organization (EMBO) in December 2014. The main points discussed centered on how to achieve 'anonymity,' 'trust,' and 'protection of data' in relation to new genomic technologies and research. Following our report of this meeting, we also raise three further issues for future consideration: the harmonization of international law in relation to genetic data protection; the complex issues around the 'dividual' nature of genetic data; and the growing commercial value of personal data. In conclusion, we stress the importance of scientists working in the area of genomic research engaging in interdisciplinary collaborations with humanities and social science scholars and addressing these complicated issues.

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

    Directory of Open Access Journals (Sweden)

    Bin Zhou

    2013-04-01

    Full Text Available 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 is proposed. Firstly, as a representation of the entirety for the first grade bloom filter, each bit of the second grade bloom filter in the TBF represents the chunks having the identical fingerprints reducing the rate of false positives. Secondly, a two-dimensional list is built corresponding to the two grade bloom filter for the absolute addresses of the data chunks with the identical fingerprints.  Finally, a new hash function class with the strong global random characteristic is set up according to the data fingerprints’ random characteristics. To reduce the comparing data greatly, TBF decreases the number of accessing disks, improves the speed of detecting the redundant data chunks, and reduces the rate of false positives which helps the improvement of the overall performance of system.

  11. 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.......g. redistribution of copy-righted contents, illegal drug trading and so on)....

  12. WATERS Expert Query Tool

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Expert Query Tool is a web-based reporting tool using the EPA’s WATERS database.There are just three steps to using Expert Query:1. View Selection – Choose what...

  13. 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.

  14. Query-By-Keywords (QBK): Query Formulation Using Semantics and Feedback

    Science.gov (United States)

    Telang, Aditya; Chakravarthy, Sharma; Li, Chengkai

    The staples of information retrieval have been querying and search, respectively, for structured and unstructured repositories. Processing queries over known, structured repositories (e.g., Databases) has been well-understood, and search has become ubiquitous when it comes to unstructured repositories (e.g., Web). Furthermore, searching structured repositories has been explored to a limited extent. However, there is not much work in querying unstructured sources. We argue that querying unstructured sources is the next step in performing focused retrievals. This paper proposed a new approach to generate queries from search-like inputs for unstructured repositories. Instead of burdening the user with schema details, we believe that pre-discovered semantic information in the form of taxonomies, relationship of keywords based on context, and attribute & operator compatibility can be used to generate query skeletons. Furthermore, progressive feedback from users can be used to improve the accuracy of query skeletons generated.

  15. 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...

  16. Querying and Manipulating Temporal Databases

    Directory of Open Access Journals (Sweden)

    Mohamed Mkaouar

    2011-03-01

    Full Text Available Many works have focused, for over twenty five years, on the integration of the time dimension indatabases (DB. However, the standard SQL3 does not yet allow easy definition, manipulation andquerying of temporal DBs. In this paper, we study how we can simplify querying and manipulatingtemporal facts in SQL3, using a model that integrates time in a native manner. To do this, we proposenew keywords and syntax to define different temporal versions for many relational operators andfunctions used in SQL. It then becomes possible to perform various queries and updates appropriate totemporal facts. We illustrate the use of these proposals on many examples from a real application.

  17. Multi-Dimensional Path Queries

    DEFF Research Database (Denmark)

    Bækgaard, Lars

    1998-01-01

    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...... that connects a pair of paths. A path expression is a function that maps a set of path sets into a path set. Path sets can be joined, filtering conditions can restrict the set of qualifying paths, and aggregation functions can be applied to path elements. In particular, the aggregation function SET can be used...... 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...

  18. SSA-Caterpillar in Group Anonymity

    CERN Document Server

    Tavrov, Dan

    2011-01-01

    Nowadays, it is a common practice to protect various types of statistical data before publishing them for different researches. For instance, when conducting extensive demographic surveys such as national census, the collected data should be at least depersonalized to guarantee proper level of privacy preservation. In practice, even more complicated methods of data protection need to be used. All these methods can be generally divided into two classes. The first ones aim at providing individual data anonymity, whereas the other ones are focused on protecting information about a group of respondents. In this paper, we propose a novel technique of providing group anonymity in statistical data using singular spectrum analysis (SSA).Also, we apply SSA to defining hidden patterns in demographic data distribution.

  19. An Internet Based Anonymous Electronic Cash System

    Directory of Open Access Journals (Sweden)

    Israt Jahan

    2015-04-01

    Full Text Available There is an increase activity in research to improve the current electronic payment system which is parallel with the progress of internet. Electronic cash system is a cryptographic payment system which offers anonymity during withdrawal and purchase. Electronic cash displays serial numbers which can be recorded to allow further tracing. Contrary to their physical counterparts, e-cash have an inherent limitation; they are easy to copy and reuse (double-spending. An observer is a tamper-resistant device, issued by the Internet bank, which is incorporated with the Internet user’s computer that prevents double-spending physically, i.e., the user has no access to her e-cash and therefore he cannot copy them. In this paper, we shall present an anonymous electronic cash scheme on the internet which incorporates tamper-resistant device with user-module.

  20. A NEW ANONYMITY CONTROLLED E-CASH SCHEME

    Institute of Scientific and Technical Information of China (English)

    Zhang Fangguo; Wang Changjie; Wang Yumin

    2002-01-01

    E-cash is a type of very important electronic payment systems. The complete anonymity of E-cash can be used for criminal activities, so E-cash should be anonymity controlled.Moreover, Elliptic Curve Cryptography(ECC) has been regard as the mainstream of current public cryptography . In this paper, a new anonymity controlled E-cash scheme based on ECC for the first time and using a new technology-one-time key pairs digital signature is designed, and its security and efficiency are analyzed. In our scheme, the coin tracing and owner tracing can be implemented.

  1. The Spatial Nearest Neighbor Skyline Queries

    CERN Document Server

    Soudani, Nasrin Mazaheri

    2011-01-01

    User preference queries are very important in spatial databases. With the help of these queries, one can found best location among points saved in database. In many situation users evaluate quality of a location with its distance from its nearest neighbor among a special set of points. There has been less attention about evaluating a location with its distance to nearest neighbors in spatial user preference queries. This problem has application in many domains such as service recommendation systems and investment planning. Related works in this field are based on top-k queries. The problem with top-k queries is that user must set weights for attributes and a function for aggregating them. This is hard for him in most cases. In this paper a new type of user preference queries called spatial nearest neighbor skyline queries will be introduced in which user has some sets of points as query parameters. For each point in database attributes are its distances to the nearest neighbors from each set of query points. ...

  2. 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

  3. 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”.

  4. Improve Query Performance On Hierarchical Data. Adjacency List Model Vs. Nested Set Model

    Directory of Open Access Journals (Sweden)

    Cornelia Gyorödi

    2016-04-01

    Full Text Available Hierarchical data are found in a variety of database applications, including content management categories, forums, business organization charts, and product categories. In this paper, we will examine two models deal with hierarchical data in relational databases namely, adjacency list model and nested set model. We analysed these models by executing various operations and queries in a web-application for the management of categories, thus highlighting the results obtained during performance comparison tests. The purpose of this paper is to present the advantages and disadvantages of using an adjacency list model compared to nested set model in a relational database integrated into an application for the management of categories, which needs to manipulate a big amount of hierarchical data.

  5. Efficient Model Querying with VMQL

    DEFF Research Database (Denmark)

    Acretoaie, Vlad; Störrle, Harald

    2015-01-01

    Context: Despite model querying being an important practical problem, existing solutions lack either usability, expressiveness, or generality. The Visual Model Query Language (VMQL) is a query byexample solution created to satisfy these requirements simultaneously. Objective: In the present paper...

  6. 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...

  7. 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

  8. 基于DNS查询行为的Bot检测%Bot detection based on DNS query activities

    Institute of Scientific and Technical Information of China (English)

    李晓利; 汤光明; 初晓

    2015-01-01

    This paper proposes a new method of identifying Bot based on DNS query activities. Firstly, as Bots usually run automatically, detection rage is narrowed down from the point of view of DNS query. Secondly, a Bot-DNS detection model is created on differences of DNS reaction behavior between Bots and normal processes, to judge whether the suspi-cious process is Bot. The experimental results show that the method can detect Bots in the early stage. It is independent of protocol and structure, and has a better detection effect.%提出一种基于DNS查询行为的检测方法。根据Bot的自动运行特性,从DNS查询的角度对主机中的进程进行初步过滤,缩小检测范围;分析Bot与其他进程的DNS反应行为模式的异同,构建Bot-DNS检测模型,在此基础上判断可疑进程是否为Bot。实验结果表明,该方法能够检测出处于生命周期早期阶段的Bot,且检测过程与Bot采用的协议结构无关,具有较好的检测效果。

  9. Quantum communications with an anonymous receiver

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A new protocol for the anonymous communication of quantum information is proposed. The anonymity of the receiver and the privacy of the quantum information are perfectly protected except with exponentially small probability in this protocol. Furthermore, this protocol uses single photons to construct anonymous entanglement instead of multipartite entangled states, and therefore it reduces quantum resources compared with the pioneering work.

  10. 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 ...

  11. Research of OWL ontology storage and query based on BaseX%基于BaseX数据库的OWL本体存储查询研究

    Institute of Scientific and Technical Information of China (English)

    胡甜甜; 曹旻

    2015-01-01

    针对目前基于关系型数据库等存储模式的本体存储查询效率较低的情况,提出使用XML数据库BaseX进行本体的存储,并设计了相应的本体存储查询架构.在对BaseX存储结构与接口的研究基础上,实现对OWL本体的存储.利用BaseX的查询接口和XQuery查询语言对OWL本体进行检索,在建立推理规则库基础上,实现本体查询扩展与推理.实验将提出的存储查询方法与基于关系型数据库的存储查询方法进行对比,验证了提出的方法具备高效的存储查询性能,同时具备本体查询的推理能力.%In view of low efficiency of ontology storage and query based on relational database or other databases, BaseX as an XML database is proposed to store ontoloy, besides, the architecture of it is also designed. Based on the research of BaseX storage structure and its interface, ontology storage is implemented. OWL ontology query is implemented by using the BaseX query interface and Xquery language, and ontology query extension and reasoning are implemented on the basis of inference rules library. The experiments compare the ontology storage and query method put forward in this paper with the classic method based on the relational database, which verify the method in this paper has more efficient storage and query performance, along with the ability of ontology query reasoning.

  12. The role of quasi-identifiers in k-anonymity revisited

    OpenAIRE

    Bettini, C.; Wang, X S; S. Jajodia

    2006-01-01

    The concept of k-anonymity, used in the recent literature to formally evaluate the privacy preservation of published tables, was introduced based on the notion of quasi-identifiers (or QI for short). The process of obtaining k-anonymity for a given private table is first to recognize the QIs in the table, and then to anonymize the QI values, the latter being called k-anonymization. While k-anonymization is usually rigorously validated by the authors, the definition of QI remains mostly inform...

  13. Reidentification and k-anonymity: a model for disclosure risk in graphs

    OpenAIRE

    Stokes, Klara; Torra, Vicenç

    2011-01-01

    In this article we provide a formal framework for reidentification in general. We define n-confusion as a concept for modelling the anonymity of a database table and we prove that n-confusion is a generalization of k- anonymity. After a short survey on the different available definitions of k- anonymity for graphs we provide a new definition for k-anonymous graph, which we consider to be the correct definition. We provide a description of the k-anonymous graphs, both for the regular and the n...

  14. A Query Language for Digital Libraries

    OpenAIRE

    Yang, Jitao

    2009-01-01

    W e introduce a data model for digital libraries and an associated query language for the discovery of objects of interest based on content or description. W e also outline possible mappings of the query language to existing standards, namely SPARQL. This paper is a short description of my doctoral work, under way, at the University of Paris South.

  15. Query Intent Disambiguation of Keyword-Based Semantic Entity Search in Dataspaces

    Institute of Scientific and Technical Information of China (English)

    Dan Yang; De-Rong Shen; Ge Yu; Yue Kou; Tie-Zheng Nie

    2013-01-01

    Keyword query has attracted much research attention due to its simplicity and wide applications.The inherent ambiguity of keyword query is prone to unsatisfied query results.Moreover some existing techniques on Web query,keyword query in relational databases and XML databases cannot be completely applied to keyword query in dataspaces.So we propose KeymanticES,a novel keyword-based semantic entity search mechanism in dataspaces which combines both keyword query and semantic query features.And we focus on query intent disambiguation problem and propose a novel three-step approach to resolve it.Extensive experimental results show the effectiveness and correctness of our proposed approach.

  16. Maximal Intersection Queries in Randomized Input Models

    CERN Document Server

    Hoffmann, Benjamin; Lifshits, Yury; Nowotka, Dirk; 10.1007/s00224-008-9154-6

    2010-01-01

    Consider a family of sets and a single set, called the query set. How can one quickly find a member of the family which has a maximal intersection with the query set? Time constraints on the query and on a possible preprocessing of the set family make this problem challenging. Such maximal intersection queries arise in a wide range of applications, including web search, recommendation systems, and distributing on-line advertisements. In general, maximal intersection queries are computationally expensive. We investigate two well-motivated distributions over all families of sets and propose an algorithm for each of them. We show that with very high probability an almost optimal solution is found in time which is logarithmic in the size of the family. Moreover, we point out a threshold phenomenon on the probabilities of intersecting sets in each of our two input models which leads to the efficient algorithms mentioned above.

  17. Design and analysis of two-layer anonymous communication system

    Institute of Scientific and Technical Information of China (English)

    WANG Wei-ping; WANG Jian-xin

    2007-01-01

    A new architecture for scalable anonymous communication system(SACS) was proposed. The users were divided into several subgroups managed by different sub-blenders, and all sub-blenders were managed by the main-blender using two layers management scheme. The identity information of members are distributed on different sub-blenders, which makes each member keep much less information and network overload greatly reduce. The anonymity and the overhead of the new scheme were analyzed and compared with that of Crowds, which shows the cost of storage and network overhead for the new scheme largely decreases while the anonymity is little degraded. The experiment results also show that the new system architecture is well scalable. The ratio of management cost of SACS to that of Crowds is about 1:25 while the value of P(I|H1+) only increases by 0.001-0.020, which shows that SACS keeps almost the same anonymity with Crowds.

  18. Anonymity and verifiability in multi-attribute reverse auction

    CERN Document Server

    Srinath, T R; Pais, Alwyn Roshan; 10.5121/ijitcs.2011.1401

    2011-01-01

    The use of e-Auction services has been increasing in recent years. Security requirements in conducting e-Auctions are mainly bid privacy, anonymity and public verifiability. Most of the secure protocols concentrate on privacy and anonymity, which are achieved through bidder-resolved multi-party computation, assuming two or more trusted third parties, either through numerous auctioneers or with asymmetric models in which the commercial entity of an auction issuer or registration manager is assumed in addition to the auctioneer. Multi-attribute reverse auctions promise higher market efficiency and effective information exchange. This work extends and uses the existing schemes. This scheme uses scoring function, winner determination in multi-attribute auctions to implement public verifiability. Anonymity is achieved through bidder side pseudonym generation. By results and analysis we say this is very simple and effective scheme. This scheme ensures public verifiability and anonymity in multi-attribute auctions w...

  19. Anonymization of DICOM Electronic Medical Records for Radiation Therapy

    OpenAIRE

    Newhauser, Wayne; Jones, Timothy; Swerdloff, Stuart; Newhauser, Warren; Cilia, Mark; Carver, Robert (British painter, ca.1730-1791); Halloran, Andy; Zhang, Rui

    2014-01-01

    Electronic medical records (EMR) and treatment plans are used in research on patient outcomes and radiation effects. In many situations researchers must remove protected health information (PHI) from EMRs. The literature contains several studies describing the anonymization of generic Digital Imaging and Communication in Medicine (DICOM) files and DICOM image sets but no publications were found that discuss the anonymization of DICOM radiation therapy plans, a key component of an EMR in a can...

  20. Accomplishing Deterministic XML Query Optimization

    Institute of Scientific and Technical Information of China (English)

    Dun-Ren Che

    2005-01-01

    As the popularity of XML (eXtensible Markup Language) keeps growing rapidly, the management of XML compliant structured-document databases has become a very interesting and compelling research area. Query optimization for XML structured-documents stands out as one of the most challenging research issues in this area because of the much enlarged optimization (search) space, which is a consequence of the intrinsic complexity of the underlying data model of XML data. We therefore propose to apply deterministic transformations on query expressions to most aggressively prune the search space and fast achieve a sufficiently improved alternative (if not the optimal) for each incoming query expression. This idea is not just exciting but practically attainable. This paper first provides an overview of our optimization strategy, and then focuses on the key implementation issues of our rule-based transformation system for XML query optimization in a database environment. The performance results we obtained from experimentation show that our approach is a valid and effective one.

  1. Exponential Lower Bound for 2-Query Locally Decodable Codes

    CERN Document Server

    Kerenidis, I; Kerenidis, Iordanis; Wolf, Ronald de

    2002-01-01

    We prove exponential lower bounds on the length of 2-query locally decodable codes. Goldreich et al. recently proved such bounds for the special case of linear locally decodable codes. Our proof shows that a 2-query locally decodable code can be decoded with only 1 quantum query, and then proves an exponential lower bound for such 1-query locally quantum-decodable codes. We also exhibit q-query locally quantum-decodable codes that are much shorter than the best known q-query classical codes. Finally, we give some new lower bounds for (not necessarily linear) private information retrieval systems.

  2. Query as Region Partition in Managing Moving Objects for Concurrent Continuous Query

    Directory of Open Access Journals (Sweden)

    Ming Qi

    2011-12-01

    Full Text Available Applications in location-based services rely on the efficient management of large scale moving objects, and one of the most important operations is real-time continuous query over moving objects, such as monitoring the objects of a certain region. In order to satisfy the high throughput and handle real-time updates and queries, it is a good choice to introduce multi-core parallel processing and managing spatial indices in main memory. In this paper, we propose a new scheme of processing continuous query on a novel spatial index based on uniform grid which is proved to be a good indexing scheme in main memory. The novelty of our index is to manage query region as the partition in the spatial index, which unified the index updating and query processing. Our experiments indicate that this sophisticated approach has better performance especially when the query is rather stationary.

  3. Querying metabolism under different physiological constraints.

    Science.gov (United States)

    Cakmak, Ali; Ozsoyoglu, Gultekin; Hanson, Richard W

    2010-04-01

    Metabolism is a representation of the biochemical principles that govern the production, consumption, degradation, and biosynthesis of metabolites in living cells. Organisms respond to changes in their physiological conditions or environmental perturbations (i.e. constraints) via cooperative implementation of such principles. Querying inner working principles of metabolism under different constraints provides invaluable insights for both researchers and educators. In this paper, we propose a metabolism query language (MQL) and discuss its query processing. MQL enables researchers to explore the behavior of the metabolism with a wide-range of predicates including dietary and physiological condition specifications. The query results of MQL are enriched with both textual and visual representations, and its query processing is completely tailored based on the underlying metabolic principles. PMID:20401946

  4. Simrank++: Query rewriting through link analysis of the click graph

    CERN Document Server

    Antonellis, Ioannis; Chang, Chi-Chao

    2007-01-01

    We focus on the problem of query rewriting for sponsored search. We base rewrites on a historical click graph that records the ads that have been clicked on in response to past user queries. Given a query q, we first consider Simrank as a way to identify queries similar to q, i.e., queries whose ads a user may be interested in. We argue that Simrank fails to properly identify query similarities in our application, and we present two enhanced version of Simrank: one that exploits weights on click graph edges and another that exploits ``evidence.'' We experimentally evaluate our new schemes against Simrank, using actual click graphs and queries form Yahoo!, and using a variety of metrics. Our results show that the enhanced methods can yield more and better query rewrites.

  5. 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

    In this paper we consider solutions to the static dictionary problem on AC0 RAMs, i.e. random access machines where the only restriction on the finite instruction set is that all computational instructions are in AC0. Our main result is a tight upper and lower bound of θ(√log n/log log n......, 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...

  6. VIS-PROCUUS: A NOVEL PROFILING SYSTEM FOR INSTIGATING USER PROFILES FROM SEARCH ENGINE LOGS BASED ON QUERY SENSE

    Directory of Open Access Journals (Sweden)

    Dr.S.K.JAYANTHI,

    2011-06-01

    Full Text Available Most commercial search engines return roughly the same results for the same query, regardless of the user’s real interest. This paper focus on user report strategy so that the browsers can obtain the web search results based on their profiles in visual mode. Users can be mined from the concept-based user profiles to perform mutual filtering. Browsers with same idea and domain can share their knowledge. From the existing user profiles the interest and domain of the users can be obtained and the search engine personalization is focused in this paper. Finally, the concept-based user profiles can be incorporated into the vis -(Visual ranking algorithm of a searchengine so that search results can be ranked according to individual users’ interests and displayed in visual mode.

  7. Research on the Index and Query of Spatial Data%空间数据索引与查询的研究

    Institute of Scientific and Technical Information of China (English)

    余冬梅

    2011-01-01

    The function of spatial database become more and more important in social and economic development nowadays, and the research on it is more and more urgent too. The article introduces spatial index, spatial query and their development, researchs on difference of index and query between spatial data and traditional relation dadabase, and analyses research thinking of optimizing spatial index and spatial query.%空间数据库在当今社会经济发展中的作用变得日趋重要,对其进行的研究也日趋迫切.对空间索引及其发展分类、空间数据查询及其与传统关系数据库的区别进行了研究,并对优化空间索引和空间数据查询的研究思路进行了分析说明.

  8. A method of personalized privacy preservation based on K-anonymization%基于K-匿名的个性化隐私保护方法研究

    Institute of Scientific and Technical Information of China (English)

    康海燕; 杨孔雨; 陈建明

    2014-01-01

    Aiming at the shortcomings of the global and local algorithms of the privacy preserving in data publishing,a method of top-down personalized generalization backtracking algorithm and its expansion algorithm based on the K-a-nonymous were proposed.The method combines the L-diversity and (s,d)-anonymization and dynamically build gen-eralization tree structure,by which users can customize the privacy security levels and separate the similar level of safety as far as possible,so as to guarantee the availability and security of the information,which can effectively prevent hom-ogeneity attack and background knowledge attack.Based on the above thinking.A system of personalized privacy pres-ervation based on K-anonymization was developed on J2SE platform.The comprehensive experimental data shows that the algorithm can improves security and guarantee the availability of information effectively.%针对数据发布隐私保护问题的全域与局域算法的不足,基于K-匿名的思想,提出了自顶向下个性化泛化回溯算法及其拓展算法,实现了数据匿名化,即结合L-多样性(s,d)个性化的规则,动态构建泛化树结构,使用户能够自定义隐私的安全等级,尽量分离相似的安全等级,从而保证信息的可用性和安全性,有效防止同质攻击和背景知识攻击。在J2 S E平台上开发了基于K-匿名的个性化隐私保护系统,并对系统进行了全面测试。实验数据表明该算法在提高安全性的同时,能有效地保证信息的可用性。

  9. GORpipe: a query tool for working with sequence data based on a Genomic Ordered Relational (GOR) architecture

    Science.gov (United States)

    Guðbjartsson, Hákon; Georgsson, Guðmundur Fr.; Guðjónsson, Sigurjón A.; Valdimarsson, Ragnar þór; Sigurðsson, Jóhann H.; Stefánsson, Sigmar K.; Másson, Gísli; Magnússon, Gísli; Pálmason, Vilmundur; Stefánsson, Kári

    2016-01-01

    Motivation: Our aim was to create a general-purpose relational data format and analysis tools to provide an efficient and coherent framework for working with large volumes of DNA sequence data. Results: For this purpose we developed the GORpipe software system. It is based on a genomic ordered architecture and uses a declarative query language that combines features from SQL and shell pipe syntax in a novel manner. The system can for instance be used to annotate sequence variants, find genomic spatial overlap between various types of genomic features, filter and aggregate them in various ways. Availability and Implementation: The GORpipe software is freely available for non-commercial academic usage and can be downloaded from www.nextcode.com/gorpipe. Contact: hakon@wuxinextcode.com Supplementary information: Supplementary data are available at Bioinformatics online. PMID:27339714

  10. Data on publications, structural analyses, and queries used to build and utilize the AlloRep database.

    Science.gov (United States)

    Sousa, Filipa L; Parente, Daniel J; Hessman, Jacob A; Chazelle, Allen; Teichmann, Sarah A; Swint-Kruse, Liskin

    2016-09-01

    The AlloRep database (www.AlloRep.org) (Sousa et al., 2016) [1] compiles extensive sequence, mutagenesis, and structural information for the LacI/GalR family of transcription regulators. Sequence alignments are presented for >3000 proteins in 45 paralog subfamilies and as a subsampled alignment of the whole family. Phenotypic and biochemical data on almost 6000 mutants have been compiled from an exhaustive search of the literature; citations for these data are included herein. These data include information about oligomerization state, stability, DNA binding and allosteric regulation. Protein structural data for 65 proteins are presented as easily-accessible, residue-contact networks. Finally, this article includes example queries to enable the use of the AlloRep database. See the related article, "AlloRep: a repository of sequence, structural and mutagenesis data for the LacI/GalR transcription regulators" (Sousa et al., 2016) [1]. PMID:27508249

  11. Web Retrieval Optimization Model Based on User's Query Intention Identification%基于用户查询意图识别的Web搜索优化模型

    Institute of Scientific and Technical Information of China (English)

    杨艺; 周元

    2012-01-01

    在对用户查询意图进行分析分类的基础上,提出了一种Web搜索优化模型.该模型通过识别用户查询意图来查询意图特征词和内容主题词的双重约束,再结合用户查询行为获得查询目标,既保证了用户查询意图的准确匹配,又自动过滤和屏蔽了不相关信息.与相关工作对比,其重点在于准确获取用户查询意图,提高用户满意度.实验结果表明,该模型在实现信息搜索准确性和用户对查询结果满意度方面比传统搜索方法有明显改善.%A Web retrieval optimization model was proposed based on the analysis and classification of user's query intention. It focuses on user's query intention identification,and can both ensure match user's query intention accurately and filter useless information automatically by means of characteristic word of query intention, content keyword and user's query behavior. Comparing with related work. This paper focused on user's query intention and user's satisfaction. Experimental results show that the model can improve significantly the accuracy in information retrieve and users' satisfaction compared with traditional methods.

  12. A search ranking algorithm based on user's query intention%基于用户查询意图的搜索排序算法

    Institute of Scientific and Technical Information of China (English)

    张美珍; 王治莹

    2012-01-01

    Study on intelligent services has being a research focus in current internet field, while the traditional Web search sorting algorithm and existing personalized scheduling can no longer meet the users query need in the government, enterprises and so on. This paper located the research core to fully understand the user's query preferences, and put forward the PageR-ank algorithm based on user preferences. Query keywords were modified using user relevance feedback in this paper, and it made search engine analysis of the potential intent using semantic analysis method more convenient. Improved algorithm perfects the reliability of the search query, and digs the users preferences topic well, which can closer to the purpose of the user 's query, and to improve search query efficiency and user satisfaction.%目前互联网技术的研究热点是智能化的、个性化的服务,而传统的Web搜索排序算法和已有的个性化排序已经不能满足政府、企业等用户的信息查询需要.本文将研究核心定位到充分理解用户查询偏好上,提出了基于用户偏好的PageRank算法.文中利用用户互反馈技术修正查询关键词,利用语义相关性技术分析用户查询意图,理解用户偏好.改进的算法完善了搜索查询的可靠性依据,能够较好地挖掘用户的偏好主题,贴近用户的查询目的,提高搜索查询效率和用户满意度.

  13. Automated Query Learning with Wikipedia and Genetic Programming

    CERN Document Server

    Malo, Pekka; Sinha, Ankur

    2010-01-01

    Most of the existing information retrieval systems are based on bag of words model and are not equipped with common world knowledge. Work has been done towards improving the efficiency of such systems by using intelligent algorithms to generate search queries, however, not much research has been done in the direction of incorporating human-and-society level knowledge in the queries. This paper is one of the first attempts where such information is incorporated into the search queries using Wikipedia semantics. The paper presents an essential shift from conventional token based queries to concept based queries, leading to an enhanced efficiency of information retrieval systems. To efficiently handle the automated query learning problem, we propose Wikipedia-based Evolutionary Semantics (Wiki-ES) framework where concept based queries are learnt using a co-evolving evolutionary procedure. Learning concept based queries using an intelligent evolutionary procedure yields significant improvement in performance whic...

  14. Enabling Ontology Based Semantic Queries in Biomedical Database Systems.

    Science.gov (United States)

    Zheng, Shuai; Wang, Fusheng; Lu, James; Saltz, Joel

    2012-01-01

    While current biomedical ontology repositories offer primitive query capabilities, it is difficult or cumbersome to support ontology based semantic queries directly in semantically annotated biomedical databases. The problem may be largely attributed to the mismatch between the models of the ontologies and the databases, and the mismatch between the query interfaces of the two systems. To fully realize semantic query capabilities based on ontologies, we develop a system DBOntoLink to provide unified semantic query interfaces by extending database query languages. With DBOntoLink, semantic queries can be directly and naturally specified as extended functions of the database query languages without any programming needed. DBOntoLink is adaptable to different ontologies through customizations and supports major biomedical ontologies hosted at the NCBO BioPortal. We demonstrate the use of DBOntoLink in a real world biomedical database with semantically annotated medical image annotations. PMID:23404054

  15. The Query Complexity of Finding a Hidden Permutation

    DEFF Research Database (Denmark)

    Afshani, Peyman; Afrawal, Manindra; Benjamin, Doerr;

    2012-01-01

    We study the query complexity of determining a hidden permutation. More specifically, we study the problem of learning a secret (z) consisting of a binary string z of length n and a permutation of [n]. The secret must be unveiled by asking queries x01n , and for each query asked, we are returned....... The deterministic query complexity is (nlogn), which, surprisingly, improves to (nloglogn) in the randomized setting. For the randomized query complexity, both the upper and lower bound are stronger than what can be achieved by standard arguments like the analysis of random queries or information......-theoretic considerations. Our proof of the (nloglogn) lower bound is based on a potential function argument, which seems to be uncommon in the query complexity literature. We find this potential function technique a very powerful tool in proving lower bounds for randomized query schemes and we expect it to find...

  16. Query-free news search

    OpenAIRE

    Henzinger, Monika; Chang, Bay-Wei; Milch, Brian; Brin, Sergey

    2003-01-01

    Many daily activities present information in the form of a stream of text, and often people can benefit from additional information on the topic discussed. TV broadcast news can be treated as one such stream of text; in this paper we discuss finding news articles on the web that are relevant to news currently being broadcast.We evaluated a variety of algorithms for this problem, looking at the impact of inverse document frequency, stemming, compounds, history, and query length on the re...

  17. FDB: A Query Engine for Factorised Relational Databases

    CERN Document Server

    Bakibayev, Nurzhan; Závodný, Jakub

    2012-01-01

    Factorised databases are relational databases that use compact factorised representations at the physical layer to reduce data redundancy and boost query performance. This paper introduces FDB, an in-memory query engine for select-project-join queries on factorised databases. Key components of FDB are novel algorithms for query optimisation and evaluation that exploit the succinctness brought by data factorisation. Experiments show that for data sets with many-to-many relationships FDB can outperform relational engines by orders of magnitude.

  18. Efficient Semi-structured Queries in Scala using XQuery Shipping

    OpenAIRE

    Borran-Dejnabadi, Fatemeh

    2006-01-01

    This project proposes a new approach to interact with database systems through programming languages. A formal query language can be integrated within modern programming languages and the semi-structured queries can be evaluated using automatic transformation and query shipping. The focus of this project is on XML queries and Scala programming language. Particularly, this project optimizes the XML-based expressions of Scala using XQuery transformation and Shipping. In this work, Scala sequenc...

  19. Anonymity: an impediment to performance in healthcare.

    Science.gov (United States)

    Karlsberg, Daniel W; Pierce, Read G

    2014-01-01

    Many teaching hospitals employ a care team structure composed of a broad range of healthcare providers with different skill sets. Each member of this team has a distinct role and a different level of training ranging from attending physician to resident, intern, and medical student. Often times, these different roles lead to greater complexity and confusion for both patients and nursing staff. It has been demonstrated that patients have a great degree of difficulty in identifying members of their care team. This anonymity also exists between nursing staff and other care providers. In order to better understand the magnitude of anonymity within the teaching hospital, a ten-question survey was sent to nurses across three different departments. Results from this survey demonstrated that 71% of nurses are "Always" or "Often" able to identify which care team is responsible for their patients, while 79% of nurses reported that they either "Often" or "Sometimes" page a provider who is not currently caring for a given patient. Furthermore, 33% of nurses felt that they were either "Rarely" or "Never" able to recognize, by face and name, attending level providers. Residents were "Rarely" or "Never" recognized by face and name 37% of the time, and interns 42% of the time. Contacting the wrong provider repeatedly leads to de facto delays in medication, therapy, and diagnosis. Additionally, these unnecessary interruptions slow workflow for both nurses and members of the care team, making hospital care less efficient and safe overall. Technological systems should focus on reducing anonymity within the hospital in order to enhance healthcare delivery. PMID:25114570

  20. GUN: An Efficient Execution Strategy for Querying the Web of Data

    OpenAIRE

    Montoya, Gabriela; Ibanez, Luis-Daniel; Skaf-Molli, Hala; Molli, Pascal; Vidal, Maria-Esther

    2013-01-01

    Local-As-View (LAV) mediators provide a uniform interface to a federation of heterogeneous data sources, attempting to execute queries against the federation. LAV mediators rely on query rewriters to translate mediator queries into equivalent queries on the federated data sources. The query rewriting problem in LAV mediators has shown to be NP-complete, and there may be an exponential number of rewritings, making unfeasible the execution or even generation of all the rewritings for some queri...

  1. 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.

  2. A NEW TOP-K CONDITIONAL XML PREFERENCE QUERIES

    Directory of Open Access Journals (Sweden)

    Shaikhah Alhazmi

    2014-09-01

    Full Text Available Preference querying technology is a very important issue in a variety of applications ranging from ecommerce to personalized search engines. Most of recent research works have been dedicated to this topic in the Artificial Intelligence and Database fields. Several formalisms allowing preference reasoning and specification have been proposed in the Artificial Intelligence domain. On the other hand, in the Database field the interest has been focused mainly in extending standard Structured Query Language (SQL and also eXtensible Markup Language (XML with preference facilities in order to provide personalized query answering. More precisely, the interest in the database context focuses on the notion of Top-k preference query and on the development of efficient methods for evaluating these queries. A Top-k preference query returns k data tuples which are the most preferred according to the user’s preferences. Of course, Top-k preference query answering is closely dependent on the particular preference model underlying the semantics of the operators responsible for selecting the best tuples. In this paper, we consider the Conditional Preference queries (CP-queries where preferences are specified by a set of rules expressed in a logical formalism. We introduce Top-k conditional preference queries (Top-k CP-queries, and the operators BestK-Match and Best-Match for evaluating these queries will be presented.

  3. Tomograph: Highlighting query parallelism in a multi-core system

    NARCIS (Netherlands)

    Gawade, M.M.; Kersten, M.L.

    2013-01-01

    Query parallelism improves serial query execution performance by orders of magnitude. Getting optimal performance from an already parallelized query plan is however difficult due to its dependency on run time factors such as correct operator scheduling, memory pressure, disk io performance, and oper

  4. Tomograph: highlighting query parallelism in a multi-core system

    NARCIS (Netherlands)

    M. Gawade; M. Kersten

    2013-01-01

    Query parallelism improves serial query execution performance by orders of magnitude. Getting optimal performance from an already parallelized query plan is however difficult due to its dependency on run time factors such as correct operator scheduling, memory pressure, disk io performance, and oper

  5. Extended query refinement for medical image retrieval.

    Science.gov (United States)

    Deserno, Thomas M; Güld, Mark O; Plodowski, Bartosz; Spitzer, Klaus; Wein, Berthold B; Schubert, Henning; Ney, Hermann; Seidl, Thomas

    2008-09-01

    The impact of image pattern recognition on accessing large databases of medical images has recently been explored, and content-based image retrieval (CBIR) in medical applications (IRMA) is researched. At the present, however, the impact of image retrieval on diagnosis is limited, and practical applications are scarce. One reason is the lack of suitable mechanisms for query refinement, in particular, the ability to (1) restore previous session states, (2) combine individual queries by Boolean operators, and (3) provide continuous-valued query refinement. This paper presents a powerful user interface for CBIR that provides all three mechanisms for extended query refinement. The various mechanisms of man-machine interaction during a retrieval session are grouped into four classes: (1) output modules, (2) parameter modules, (3) transaction modules, and (4) process modules, all of which are controlled by a detailed query logging. The query logging is linked to a relational database. Nested loops for interaction provide a maximum of flexibility within a minimum of complexity, as the entire data flow is still controlled within a single Web page. Our approach is implemented to support various modalities, orientations, and body regions using global features that model gray scale, texture, structure, and global shape characteristics. The resulting extended query refinement has a significant impact for medical CBIR applications. PMID:17497197

  6. Templates and Queries in Contextual Hypermedia

    DEFF Research Database (Denmark)

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

    2006-01-01

    This paper presents a new definition of context for context-aware computing based on a model that relies on dynamic queries over structured objects. This new model enables developers to flexibly specify the relationship between context and context data for their context-aware applications. We...... discuss a framework, HyConSC, that implements this model and describe how it can be used to build new contextual hypermedia systems. Our framework aids the developer in the iterative development of contextual queries (via a dynamic query browser) and offers support for con-text matching, a key feature...

  7. Privacy-Preserving Updates to Anonymous Databases

    OpenAIRE

    Sivasubramanian, R.; K.P. KALIYAMURTHIE

    2013-01-01

    Suppose a medical facility connected with a research institution and the researchers can use themedical details of a patient without knowing the personal details. Thus the research data base used by theresearchers must be anonymized (Sanitized). We can consider another problem in the area of census.Individuals give the private information to a trusted party (Census Bureau) and the census bureau mustpublish anonymized or sanitized version of data. So anonymization is done for privacy. Our work...

  8. 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

  9. 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...

  10. Constraint-based query distribution framework for an integrated global schema

    DEFF Research Database (Denmark)

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

    2009-01-01

    Distributed heterogeneous data sources need to be queried uniformly using global schema. Query on global schema is reformulated so that it can be executed on local data sources. Constraints in global schema and mappings are used for source selection, query optimization, and querying partitioned and...... replicated data sources. The provided system is all XML-based which poses query in XML form, transforms, and integrates local results in an XML document. Contributions include the use of constraints in our existing global schema which help in source selection and query optimization, and a global query...... distribution framework for querying distributed heterogeneous data sources. ©2009 IEEE....

  11. 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....

  12. 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 ...

  13. XIRAF: Ultimate Forensic Querying

    NARCIS (Netherlands)

    Alink, W.; Bhoedjang, R.; Vries, A.P. de; Boncz, P.A.

    2006-01-01

    This paper describes a novel, XML-based approach towards managing and querying forensic traces extracted from digital evidence. This approach has been implemented in XIRAF, a prototype system for forensic analysis. XIRAF systematically applies forensic analysis tools to evidence files (e.g., hard di

  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...

  15. Medical Query Language

    OpenAIRE

    Morgan, Mary M.; Beaman, Peter D.; Shusman, Daniel J.; Hupp, Jon A.; Zielstorff, Rita D.; Barnett, G. Octo

    1981-01-01

    This paper describes the Medical Query Language (MQL), a “formal” language which enables unsophisticated users, having no background in programming or computer science, to express information retrieval and analysis questions of their data bases. MQL is designed to access any MUMPS data base. Most MQL applications to date have dealt with the COmputer STored Ambulatory Record (COSTAR) data base.

  16. 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....

  17. Broadcast-Based Spatial Queries

    Institute of Scientific and Technical Information of China (English)

    Kwang-Jin Park; Moon-Bae Song; Chong-Sun Hwang

    2005-01-01

    Indexing techniques have been developed for wireless data broadcast environments, in order to conserve the scarce power resources of the mobile clients. However, the use of interleaved index segments in a broadcast cycle increases the average access latency for the clients. In this paper, the broadcast-based spatial query processing methods (BBS)are presented for the location-based services. In the BBS, broadcasted data objects are sorted sequentially based on their locations, and the server broadcasts the location dependent data along with an index segment. Then, a sequential prefetching and caching scheme is designed to reduce the query response time. The performance of this scheme is investigated in relation to various environmental variables, such as the distributions of the data objects, the average speed of the clients and the size of the service area.

  18. Distributed anonymous discrete function computation

    CERN Document Server

    Hendrickx, Julien M; Tsitsiklis, John N

    2010-01-01

    We propose a model for deterministic distributed function computation by a network of identical and anonymous nodes. In this model, each node has bounded computation and storage capabilities that do not grow with the network size. Furthermore, each node only knows its neighbors, not the entire graph. Our goal is to characterize the class of functions that can be computed within this model. In our main result, we provide a necessary condition for computability which we show to be nearly sufficient, in the sense that every function that violates this condition can at least be approximated. The problem of computing suitably rounded averages in a distributed manner plays a central role in our development; we provide an algorithm that solves it in time that grows quadratically with the size of the network.

  19. A Preliminary Mapping of Web Queries Using Existing Image Query Schemes.

    Science.gov (United States)

    Jansen, Bernard J.

    End user searching on the Web has become the primary method of locating images for many people. This study investigates the nature of Web image queries by attempting to map them to known image classification schemes. In this study, approximately 100,000 image queries from a major Web search engine were collected in 1997, 1999, and 2001. A…

  20. A query integrator and manager for the query web.

    Science.gov (United States)

    Brinkley, James F; Detwiler, Landon T

    2012-10-01

    We introduce two concepts: the Query Web as a layer of interconnected queries over the document web and the semantic web, and a Query Web Integrator and Manager (QI) that enables the Query Web to evolve. QI permits users to write, save and reuse queries over any web accessible source, including other queries saved in other installations of QI. The saved queries may be in any language (e.g. SPARQL, XQuery); the only condition for interconnection is that the queries return their results in some form of XML. This condition allows queries to chain off each other, and to be written in whatever language is appropriate for the task. We illustrate the potential use of QI for several biomedical use cases, including ontology view generation using a combination of graph-based and logical approaches, value set generation for clinical data management, image annotation using terminology obtained from an ontology web service, ontology-driven brain imaging data integration, small-scale clinical data integration, and wider-scale clinical data integration. Such use cases illustrate the current range of applications of QI and lead us to speculate about the potential evolution from smaller groups of interconnected queries into a larger query network that layers over the document and semantic web. The resulting Query Web could greatly aid researchers and others who now have to manually navigate through multiple information sources in order to answer specific questions.

  1. Does anonymity increase the reporting of mental health symptoms?

    Directory of Open Access Journals (Sweden)

    Fear Nicola T

    2012-09-01

    Full Text Available Abstract Background There is no doubt that the perceived stigma of having a mental disorder acts as a barrier to help seeking. It is possible that personnel may be reluctant to admit to symptoms suggestive of poor mental health when such data can be linked to them, even if their personal details are only used to help them access further care. This may be particularly relevant because individuals who have a mental health problem are more likely to experience barriers to care and hold stigmatizing beliefs. If that is the case, then mental health screening programmers may not be effective in detecting those most in need of care. We aimed to compare mental health symptom reporting when using an anonymous versus identifiable questionnaire among UK military personnel on deployment in Iraq. Methods Survey among UK military personnel using two questionnaires, one was anonymous (n = 315 and one collected contact details (i.e. identifiable, n = 296. Distribution was by alternate allocation. Data were collected in Iraq during January-February 2009. Results No significant difference in the reporting of symptoms of common mental disorders was found (18.1% of identifiable vs. 22.9% of anonymous participants. UK military personnel were more likely to report sub-threshold and probable PTSD when completing questionnaires anonymously (sub-threshold PTSD: 2.4% of identifiable vs. 5.8% of anonymous participants; probable PTSD: 1.7% of identifiable vs. 4.8% of anonymous participants. Of the 11 barriers to care and perceived social stigma statements considered, those completing the anonymous questionnaire compared to those completing the identifiable questionnaire were more likely to endorse three statements: “leaders discourage the use of mental health services” (9.3% vs. 4.6%, “it would be too embarrassing” (41.6% vs. 32.5% and “I would be seen as weak” (46.6% vs. 34.2%. Conclusions We found a significant effect on the reporting of sub

  2. Query Adaptive Image Retrieval System

    Directory of Open Access Journals (Sweden)

    Amruta Dubewar

    2014-03-01

    Full Text Available Images play a crucial role in various fields such as art gallery, medical, journalism and entertainment. Increasing use of image acquisition and data storage technologies have enabled the creation of large database. So, it is necessary to develop appropriate information management system to efficiently manage these collections and needed a system to retrieve required images from these collections. This paper proposed query adaptive image retrieval system (QAIRS to retrieve images similar to the query image specified by user from database. The goal of this system is to support image retrieval based on content properties such as colour and texture, usually encoded into feature vectors. In this system, colour feature extracted by various techniques such as colour moment, colour histogram and autocorrelogram and texture feature extracted by using gabor wavelet. Hashing technique is used to embed high dimensional image features into hamming space, where search can be performed by hamming distance of compact hash codes. Depending upon minimum hamming distance it returns the similar image to query image.

  3. EHR query language (EQL)--a query language for archetype-based health records.

    Science.gov (United States)

    Ma, Chunlan; Frankel, Heath; Beale, Thomas; Heard, Sam

    2007-01-01

    OpenEHR specifications have been developed to standardise the representation of an international electronic health record (EHR). The language used for querying EHR data is not as yet part of the specification. To fill in this gap, Ocean Informatics has developed a query language currently known as EHR Query Language (EQL), a declarative language supporting queries on EHR data. EQL is neutral to EHR systems, programming languages and system environments and depends only on the openEHR archetype model and semantics. Thus, in principle, EQL can be used in any archetype-based computational context. In the EHR context described here, particular queries mention concepts from the openEHR EHR Reference Model (RM). EQL can be used as a common query language for disparate archetype-based applications. The use of a common RM, archetypes, and a companion query language, such as EQL, semantic interoperability of EHR information is much closer. This paper introduces the EQL syntax and provides example clinical queries to illustrate the syntax. Finally, current implementations and future directions are outlined. PMID:17911747

  4. Performance of native SPARQL query processors

    OpenAIRE

    Maharajan, Shridevika

    2012-01-01

    Expressing data in RDF is one approach for making data available as Linked Data on the Web. Searching such data requires an RDF database engine providing some query language. The standard query language for RDF is called SPARQL. An RDF database engine can either be a middleware on top of an existing (relational) database or a native RDF store having its own internal data repository. Organizations often have difficulties to decide which solution they should adopt because there are few comprehe...

  5. Mining tree-query associations in graphs

    CERN Document Server

    Hoekx, Eveline

    2010-01-01

    New applications of data mining, such as in biology, bioinformatics, or sociology, are faced with large datasetsstructured as graphs. We introduce a novel class of tree-shapedpatterns called tree queries, and present algorithms for miningtree queries and tree-query associations in a large data graph. Novel about our class of patterns is that they can containconstants, and can contain existential nodes which are not counted when determining the number of occurrences of the patternin the data graph. Our algorithms have a number of provableoptimality properties, which are based on the theory of conjunctive database queries. We propose a practical, database-oriented implementation in SQL, and show that the approach works in practice through experiments on data about food webs, protein interactions, and citation analysis.

  6. 分布式空间拓扑连接查询优化处理算法%Research on the Distributed Spatial Topological Query Optimization Algorithm

    Institute of Scientific and Technical Information of China (English)

    杨典华

    2013-01-01

    针对传统分布式数据库查询应用于分布式空间数据库查询带来的传输和处理代价高的问题,本文结合已有分布式跨边界片段连接优化方法,深入研究了分布式空间拓扑连接查询处理,提出跨边界连接优化的空间查询优化算法,丰富了传统的分布式查询的关系代数等价变换规则。同时,针对不同片段连接类型的分布式空间查询全局优化策略,实现了分布式空间查询分解与数据本地化,从而优化分布式查询中的数据传输所付出的高昂代价。最后,提出了结点归并、连接归并树、执行结点、执行计划树等分布式查询优化方法,利用相应归并和优化算法将全局空间查询转化为各个场地局部空间数据库的具体执行计划,消除分布式查询中的冗余计算,优化查询计算策略,从而解决分布式空间查询中的处理代价高的问题。通过分布式空间查询实验表明,本文的算法能够较好地提高分布式空间查询的性能。%Due to complex data structure, complicated spatial relationship and massive data volume, distributed spatial query is a time-consuming processing, which will cause high transmission and processing cost. Query pro-cessing method in traditional distributed database cannot satisfy the demands of query in distributed geospatial database. Therefore, new query methods in distributed geospatial database need to be studied. In this paper, the distributed spatial join query processing is deeply studied based on the existing optimizing methods of the con-ventional query processing in traditional distributed database, and a series of transformation rules of relational al-gebra expression based on cross-border topological join optimization rules are proposed. The processed query tree is optimized by equivalent transformation after data localization. The global optimized method of distributed spatial join query for different fragments is

  7. Anonymous pastoral care for problems pertaining to sexuality.

    Science.gov (United States)

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

    2014-12-01

    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 on the other. We analyzed helpseeking questions of two protestant Christian organizations in the Netherlands providing anonymous pastoral care: Refoweb and EO-Nazorg. Sexual themes were addressed in 19 and 2.3 % of the submitted questions, respectively. Of the helpseekers, 56 % is female, 15 % male, and 29 % unknown. Questions and problems for which people seek anonymous pastoral care focus primarily on premarital abstinence, gender roles, contraception, sexual orientation and masturbation. The authority of the Bible seems to be important for questioners, especially when dealing with ethical questions. Different relations between the normativity of the church tradition and sexual and spiritual health are discussed. PMID:23784431

  8. Performance Oriented Query Processing In GEO Based Location Search Engines

    CERN Document Server

    Umamaheswari, M

    2010-01-01

    Geographic location search engines allow users to constrain and order search results in an intuitive manner by focusing a query on a particular geographic region. Geographic search technology, also called location search, has recently received significant interest from major search engine companies. Academic research in this area has focused primarily on techniques for extracting geographic knowledge from the web. In this paper, we study the problem of efficient query processing in scalable geographic search engines. Query processing is a major bottleneck in standard web search engines, and the main reason for the thousands of machines used by the major engines. Geographic search engine query processing is different in that it requires a combination of text and spatial data processing techniques. We propose several algorithms for efficient query processing in geographic search engines, integrate them into an existing web search query processor, and evaluate them on large sets of real data and query traces.

  9. Anonymity in Classroom Voting and Debating

    Science.gov (United States)

    Ainsworth, Shaaron; Gelmini-Hornsby, Giulia; Threapleton, Kate; Crook, Charles; O'Malley, Claire; Buda, Marie

    2011-01-01

    The advent of networked environments into the classroom is changing classroom debates in many ways. This article addresses one key attribute of these environments, namely anonymity, to explore its consequences for co-present adolescents anonymous, by virtue of the computer system, to peers not to teachers. Three studies with 16-17 year-olds used a…

  10. 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 mysterio

  11. A Self-Encryption Remote User Anonymous Authentication Scheme Using Smart Cards

    Institute of Scientific and Technical Information of China (English)

    LU Rong-xing; CAO Zhen-fu; SU Ren-wang

    2006-01-01

    Remote user authentication is essential in distributed network environment to protect unauthorized access of a networked system. However, most of those existing remote user authentication schemes have not provided the user identity anonymity, while user anonymity is particularly important in some practical applications.Therefore, based on self-encryption mechanism, a new remote user authentication scheme was proposed. The scheme not only has no need of maintaining a password table at the remote server, but also can protect the user's anonymity.

  12. Study on Query Expansion of AWAR Algorithm In Information Retrieval%AWAR算法在信息检索查询扩展中的研究

    Institute of Scientific and Technical Information of China (English)

    郝慎学

    2013-01-01

    According to the existing problem of that the commonly used information retrieval algorithms is low in query performance. This paper proposed an information retrieval and extended query model based on AWAR algorithm, the model first uses the traditional vector space model algorithm to carry out the initial survey of the retrieval target, and then using the minimun complete weighted confidence threshold to generate completely weighted association rules, finally extracting extension word according to the rules and getting the query results. Experiments show that the information retrieval and extended query model based on AWAR algorithm has a better retrieval performance than the traditional vector space model algorithm and the query expansion retrieval algorithm based on local context analysis.%针对目前常用的信息检索算法普遍存在查询性能不高的问题。本文提出了一种基于AWAR算法的信息检索扩展查询模型,该模型首先采用传统向量空间模型算法对检索目标进行初检,然后利用最小完全加权置信度阈值生成完全加权关联规则,最后根据规则提取扩展词,得到查询结果。实验表明,基于AWAR算法的信息检索扩展查询模型的检索性能比传统向量空间模型算法和基于局部上下文分析的查询扩展的检索算法要高。

  13. 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.

  14. A Semantic Graph Query Language

    Energy Technology Data Exchange (ETDEWEB)

    Kaplan, I L

    2006-10-16

    Semantic graphs can be used to organize large amounts of information from a number of sources into one unified structure. A semantic query language provides a foundation for extracting information from the semantic graph. The graph query language described here provides a simple, powerful method for querying semantic graphs.

  15. Range Query Processing in Multidisk Systems

    Institute of Scientific and Technical Information of China (English)

    李建中

    1992-01-01

    In order to reduce the disk access time,a database can be stored on several simultaneously accessible disks.In this paper,we are concerned with the dynamic d-attribute database allocation problem for range queries,An allocation method,called coordinate moule allocation method,is proposed to allocate data in a d-attribute database among disks so that the maximum disk accessing concurrency can be achieved for range queries.Our analysis and experiments show that the method achieves the optimum or near-optimum parallelism for range queries.The paper offers the conditions under which the method is optimal .The worst case bounds of the performance of the method are also given.In addition,the parallel algorithm of processing range queries in described at the end of the paper.The method has been used in the statistic and scientific database management system whic is being designed by us.

  16. Metadata for Approximate Query Answering Systems

    Directory of Open Access Journals (Sweden)

    Francesco Di Tria

    2012-01-01

    Full Text Available In business intelligence systems, data warehouse metadata management and representation are getting more and more attention by vendors and designers. The standard language for the data warehouse metadata representation is the Common Warehouse Metamodel. However, business intelligence systems include also approximate query answering systems, since these software tools provide fast responses for decision making on the basis of approximate query processing. Currently, the standard meta-model does not allow to represent the metadata needed by approximate query answering systems. In this paper, we propose an extension of the standard metamodel, in order to define the metadata to be used in online approximate analytical processing. These metadata have been successfully adopted in ADAP, a web-based approximate query answering system that creates and uses statistical data profiles.

  17. 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.

  18. 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.

  19. Applying l-Diversity in anonymizing collaborative social network

    CERN Document Server

    Prasad, Ajay; Mitra, A; Singh, Arjun; Gour, Deepak

    2010-01-01

    To date publish of a giant social network jointly from different parties is an easier collaborative approach. Agencies and researchers who collect such social network data often have a compelling interest in allowing others to analyze the data. In many cases the data describes relationships that are private and sharing the data in full can result in unacceptable disclosures. Thus, preserving privacy without revealing sensitive information in the social network is a serious concern. Recent developments for preserving privacy using anonymization techniques are focused on relational data only. Preserving privacy in social networks against neighborhood attacks is an initiation which uses the definition of privacy called k-anonymity. k-anonymous social network still may leak privacy under the cases of homogeneity and background knowledge attacks. To overcome, we find a place to use a new practical and efficient definition of privacy called ldiversity. In this paper, we take a step further on preserving privacy in ...

  20. Conceptual querying through ontologies

    DEFF Research Database (Denmark)

    Andreasen, Troels; Bulskov, Henrik

    2009-01-01

    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...... 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...... 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....

  1. Querying genomic databases

    Energy Technology Data Exchange (ETDEWEB)

    Baehr, A.; Hagstrom, R.; Joerg, D.; Overbeek, R.

    1991-09-01

    A natural-language interface has been developed that retrieves genomic information by using a simple subset of English. The interface spares the biologist from the task of learning database-specific query languages and computer programming. Currently, the interface deals with the E. coli genome. It can, however, be readily extended and shows promise as a means of easy access to other sequenced genomic databases as well.

  2. Intelligent Visual Analytics Queries

    OpenAIRE

    Hao, Ming C.; Dayal, Umeshwar; Keim, Daniel A.; Morent, Dominik; Schneidewind, Jörn

    2007-01-01

    Visualizations of large multi-dimensional data sets, occurring in scientific and commercial applications, often reveal interesting local patterns. Analysts want to identify the causes and impacts of these interesting areas, and they also want to search for similar patterns occurring elsewhere in the data set. In this paper we introduce the Intelligent Visual Analytics Query (IVQuery) concept that combines visual interaction with automated analytical methods to support analysts in discovering ...

  3. Application of Steganography for Anonymity through the Internet

    CERN Document Server

    Bahi, Jacques M; Friot, Nicolas; Guyeux, Christophe

    2012-01-01

    In this paper, a novel steganographic scheme based on chaotic iterations is proposed. This research work takes place into the information hiding security framework. The applications for anonymity and privacy through the Internet are regarded too. To guarantee such an anonymity, it should be possible to set up a secret communication channel into a web page, being both secure and robust. To achieve this goal, we propose an information hiding scheme being stego-secure, which is the highest level of security in a well defined and studied category of attacks called "watermark-only attack". This category of attacks is the best context to study steganography-based anonymity through the Internet. The steganalysis of our steganographic process is also studied in order to show it security in a real test framework.

  4. Path-partitioned encoding supports wildcard-awareness twig queries

    Institute of Scientific and Technical Information of China (English)

    XU; Xiao-shuang; FENG; Yu-cai; WANG; Feng

    2009-01-01

    Finding all occurrences of a twig query in an XML database is a core operation for efficient evaluation of XML queries. It is important to effectively handle twig queries with wildcards. In this paper, a novel path-partitioned encoding scheme is proposed for XML documents to capture paths of all elements, and a twig query is modeled as an XPattern extended from tree pattern. After definition, simplification, normalization, verification and initialization of the XPattern, both work sets and a join plan are generated. According to these measures, an effective algorithm to answer for a twig query, called DMTwig, is designed without unnecessary elements and invalid structural joins. The algorithm can adaptively deal with twig queries with branch([]), child edge(/), descendant edge(//), and wildcard(*)synthetically. We show that path-partitioned encoding scheme and XPattern guarantee the I/O and CPU optimality for twig queries. Experiments on representative data set indicate that the proposed solution performs significantly.

  5. An Anonymous Node State Transition Model Based on Semi-Markov Process%一种基于半马尔可夫过程的匿名节点状态转移模型

    Institute of Scientific and Technical Information of China (English)

    郝建国; 刘卫东; 戴一奇

    2011-01-01

    To reveal the effect of node misbehaviors and defense mechanisms against them on the node cooperation in anonymous routing protocol for MANET (Mobile Ad-hoc NETworks) ,an anonymous node state transition model based on semi-Markov process is proposed on the features of anonymous node state transition. Under this model, according to the characteristics of large energy consumption and high de mand for privacy protection of anonymous node,we give a theoretical estimation of the limiting probability of node states,and present a model of the node state transition probability matrix and transition time expectation matrix. An experimental analysis to the effect of different model paranetres on the limiting probability of node states verifies the model' s validity at last.%为揭示MANET(Mobile Ad-hoc NETworks)匿名路由协议中节点不端行为及其抵御机制对节点协作性的影响,本文根据匿名节点状态转移的特点,提出了一种基于半马尔可夫过程的匿名节点状态转移模型.在该模型下,针对MANET匿名路由协议中节点能量消耗大和隐私保护要求高的特点,对节点状态极限概率进行了理论估计,给出了节点状态转移概率矩阵和转移期望时间矩阵的理论模型.最后,用实验分析了不同模型参数对节点状态极限概率的影响,验证了本文模型的有效性.

  6. 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.

  7. 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.'

  8. Anonymous authentication protocol for multi-services in wireless environments

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    To provide mutual authentication among users, wireless networks, and service providers in roaming wireless environments, this article presents an anonymous authentication and access control protocol. Bases on this protocol, entities of different trusted domains can mutually authenticate each other and preserve the anonymity of users. Hybrid cryptosystem, secret splitting, and hash chains are used in the protocol, which decrease computational loads and establish trusted relations for both entities. The proposed protocol has the least computation complexity compared with other protocols, whereas, the security has been significantly improved.

  9. RESEARCH ON ANONYMOUS COMMUNICATION TECHNOLOGIES IN AD HOC NETWORKS%无线 Ad hoc 网络匿名通信技术研究

    Institute of Scientific and Technical Information of China (English)

    王秀芝; 石志东; 房卫东; 张小珑; 单联海

    2016-01-01

    无线 Ad hoc 网络(MANET)的多跳、自组织、无固定设施以及运算资源有限等特性,使得传统网络中复杂度高的安全算法难以应用于其中。而采用与匿名技术相结合的安全机制,可较好地解决节点隐私和通信关系保密的安全问题。针对现有的匿名技术,采用对比分析的方法,对传统网络的匿名技术进行分析,总结技术上的优缺点,研究 Ad hoc 网络的匿名技术,并对比分析各种匿名通信协议的安全性能,为后续的研究与应用提供帮助。%Due to the features of Ad hoc networks such as multi-hop,self-organisation,non-infrastructure and limited resource,the security algorithms with high complexity in traditional networks are hard to be used in it.However to use the security mechanism combining with anonymous technology can well solve the security problem in regard to nodes’privacy and communication relationship secret.In this paper,targeted at existing anonymous technologies,we analyse their use in traditional networks with the method of comparative analysis, summarise the advantages and disadvantages in terms of technology,and meanwhile study the anonymous technologies used in Ad hoc networks,as well as compare and analyse the security performances of various anonymous communication protocol,these provide the help for subsequent researches and applications.

  10. Study and Practice of the Anonymity Technology Model for Electronic Commerce Based on MPLS%基于MPLS的电子商务匿名技术模型研究与实践

    Institute of Scientific and Technical Information of China (English)

    解争龙; 吴振强; 弋改珍; 王芳

    2012-01-01

    电子商务作为贸易手段已经进入人们的日常生活,如何保护商业机密、个人隐私是电子商务贸易中急需解决的问题.根据MPLS工作原理,在Onion匿名技术的基础上,建立基于MPLS的电子商务匿名模型,使用Nettrace对纯Onion匿名模型与基于MPLS匿名模型从安全和效率进行了比较.结果表明,基于MPLS匿名技术在保护用户隐私的同时,提高Onion匿名模型的通信效率.%Electronic Commerce has stepped into the daily life of people.But how to protect the business confidentiality and personal privacy is one of the problems resolved quickly.According to the operating principle of MPLS,on the anonymity technology of Onion,their security and efficiency has been compared for the anonymity models of the pure Onion and the MPLS.The results show that the anonymity technology of MPLS-based protected the user's privacy,while developed the efficiency of the model of Onion.

  11. On the Editor's Role in the Experts-Anonymously-Reviewing System%论责任编辑在专家匿名审稿制中的主导作用

    Institute of Scientific and Technical Information of China (English)

    兰甲云

    2009-01-01

    By analyzing the status of the academic journal reviewing system and the problems springing out in the current experts-anonymously-reviewing system, this essay discusses on the common cognitive misunderstandings of the experts-anonymously-reviewing system,which still needs further improvement. It proposes that, in addition to highlighting the experts'subjectivity, we should strengthen the editor's leading role in the experts-anonymously-reviewing system.%分析了学术期刊审稿制度的现状,论述了当前学术期刊界普遍采用的专家匿名审稿制需要注意的问题,剖析了常见的专家匿名审稿制的认识误区,建议完善专家匿名审稿制度,在发挥专家的主体作用的同时,应大力加强责任编辑在专家匿名审稿制度中的主导作用.

  12. Parking Query in Vehicular Delay-Tolerant Networks with Privacy Protection Based on Secure Multiparty Computation

    Directory of Open Access Journals (Sweden)

    Haiping Huang

    2015-01-01

    Full Text Available Within vehicular delay-tolerant network, conflict exists in the scenario of which two vehicles happen to choose the same parking space. To solve this problem, two protocols are proposed, respectively, which are called privacy protection protocol based on secure multiparty computation and routing protocol based on angle and density. The proposed methods prevent the leaking of privacy information of the vehicles involved during the parking space seeking process and improve the performance of the transmission ratio and reduce the transmission delay by unifying the directions of messages and choosing the vehicle of the highest distribution density as the next hop. The results of the simulation show the efficiency of our method.

  13. ANONYMOUS OFF-LINE ELECTRONIC PAYMENT SYSTEM WITH MULTIPLE BANKS

    Institute of Scientific and Technical Information of China (English)

    Liang Jian; Ao Qingyun; Chen Ying

    2001-01-01

    This letter presents an anonymous off-line electronic payment model with multiple issuing-banks and gives an implementation scheme based on the discrete logarithm problem and the random oracle model. Comparing with previous works, the proposed scheme benefits from no involvement of customer group authority and its security depends on the known difficulty of resolving general discrete logarithm problem.

  14. Semantic Web Query on e-Governance Data and Designing Ontology for Agriculture Domain

    Directory of Open Access Journals (Sweden)

    Swaran Lata

    2013-07-01

    Full Text Available Indian agriculture has made rapid progress on the agricultural front during the past three decades and isin a queue of the major producer in the world. But still it has long way to go and meet challenges aheadsuch as communication, resources, and availability at right time at right place. The web has had an amazingexistence and it has been the driving force for a cause to grow information across boundaries, enablingeffective communication and 24x7 service availability all leading to a digital information based economythat we have today. Despite that, its direct influence has reached to a small percentage of human population.Since localization populated with India and the applications are translated and adapted for Indian users.With the possible localization of spread raw formatted Indian government data, at different locationsare thought to have integrated with each other using the internet web technology as – Semantic Web Network.

  15. 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.

  16. Semantic Web Query on E-Governance Data and Designing Ontology for Agriculture Domain

    Directory of Open Access Journals (Sweden)

    Swaran Lata

    2013-07-01

    Full Text Available Indian agriculture has made rapid progress on the a gricultural front during the past three decades and is in a queue of the major producer in the world. But still it has long way to go and meet challenges ahead such as communication, resour ces, and availability at right time at right place. The web has had an amazing existence and it has been the driving force for a cause to grow information across boundaries, enabling effect ive communication and 24x7 service availability all leading to a digital information b ased economy that we have today. Despite that, its direct influence has reached to a small percent age of human population. Since localization populated with India and the applications are trans lated and adapted for Indian users. With the possible localization of spread raw formatted India n government data, at different locations are thought to have integrated with each other using th e internet web technology as – Semantic Web Network

  17. Improved Anonymous Authentication Scheme Based on Link-layer Location Privacy%基于链路层位置隐私的改进匿名认证方案

    Institute of Scientific and Technical Information of China (English)

    慎耀辉; 王晓明

    2014-01-01

    Through the analysis of wireless network environment based on the protection of link layer forward secure location privacy mutually anonymous authentication scheme, this paper points out that this scheme in the authentication phase does not fully realize user anonymous authentication, but also exists the impersonation attack, Denial of Service(DoS) attack and other security issues. Therefore, this paper proposes an improved anonymous authentication scheme. The improved scheme builds on the elliptic curve discrete logarithm problem and secures one-way hash function, uses the Lagrange interpolation method to generate the authentication parameters for different users, and uses the random masking technique to achieve the user anonymous authentication. Security and performance analysis results show that the improved scheme can overcome the counterfeit attack and DoS attack, achieve completely user anonymous authentication, and protect the privacy of mobile users, and it does not increase the amount of computation for mobile users and system communication.%通过分析基于链路层的保护前向安全的位置隐私相互匿名认证方案,指出该方案在认证阶段并未完全实现用户匿名认证,同时还存在假冒攻击和拒绝服务攻击等安全问题,进而提出一个改进的匿名认证方案。该方案建立在椭圆曲线离散对数问题和单向哈希函数上,利用拉格朗日插值法为每个用户生成不同的认证参数,并采用随机掩蔽技术实现用户的匿名隐私认证。安全性和性能分析结果表明,改进方案可抵抗假冒攻击和拒绝服务攻击,实现用户完全匿名认证,达到保护移动用户隐私的目的,并且未增加移动用户的计算量和系统的通信量。

  18. Providing Group Anonymity Using Wavelet Transform

    CERN Document Server

    Chertov, Oleg

    2010-01-01

    Providing public access to unprotected digital data can pose a threat of unwanted disclosing the restricted information. The problem of protecting such information can be divided into two main subclasses, namely, individual and group data anonymity. By group anonymity we define protecting important data patterns, distributions, and collective features which cannot be determined through analyzing individual records only. An effective and comparatively simple way of solving group anonymity problem is doubtlessly applying wavelet transform. It's easy-to-implement, powerful enough, and might produce acceptable results if used properly. In the paper, we present a novel method of using wavelet transform for providing group anonymity; it is gained through redistributing wavelet approximation values, along with simultaneous fixing data mean value and leaving wavelet details unchanged (or proportionally altering them). Moreover, we provide a comprehensive example to illustrate the method.

  19. Intelligent Database Flexible Querying System by Approximate Query Processing

    CERN Document Server

    Tlili, Oussama; Ounelli, Habib

    2012-01-01

    Database flexible querying is an alternative to the classic one for users. The use of Formal Concepts Analysis (FCA) makes it possible to make approximate answers that those turned over by a classic DataBase Management System (DBMS). Some applications do not need exact answers. However, flexible querying can be expensive in response time. This time is more significant when the flexible querying require the calculation of aggregate functions ("Sum", "Avg", "Count", "Var" etc.). In this paper, we propose an approach which tries to solve this problem by using Approximate Query Processing (AQP).

  20. 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.

  1. Anonymous pastoral care for problems pertaining to sexuality

    NARCIS (Netherlands)

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

    2013-01-01

    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 o

  2. Online Role-Play: Anonymity, Engagement and Risk.

    Science.gov (United States)

    Bell, Maureen

    2001-01-01

    Discussion of role-play focuses on a case study of an asynchronous, anonymous online role-play at an Australian university within a WebCT bulletin board that was designed as an alternative to an existing face-to-face workshop to offer more flexible access for participants. Suggests further research needs. (Author/LRW)

  3. 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...

  4. 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.

  5. 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。

  6. OBLIVIOUS TRANSFER WITH ACCESS CONTROL AND IDENTITYBASED ENCRYPTION WITH ANONYMOUS KEY ISSUING

    Institute of Scientific and Technical Information of China (English)

    Xu Lingling; Zhang Fangguo; Wen Yamin

    2011-01-01

    In ACM'CCS 2009,Camenisch,et al.proposed the Obhvious Transfer with Access Control (AC-OT) in which each item is associated with an attribute set and can only be available,on request,to the users who have all the attributes in the associated set.Namely,AC-OT achieves access control policy for conjunction of attributes.Essentially,the functionality of AC-OT is equivalent to the simplified version that we call AC-OT-SV:for each item,one attribute is associated with it,and it is requested that only the users who possess the associated attribute can obtain the item by queries.On one hand,AC-OT-SV is a special case of AC-OT when there is just one associated attribute with each item.On the other hand,any AC-OT can be realized by an AC-OT-SV.In this paper,we first present a concrete AC-OT-SV protocol which is proved to be secure in the model defined by Camenisch,et al..Then from the protocol,interestingly,a concrete Identity-Based Encryption (IBE) with Anonymous Key Issuing (AKI) is given which is just a direct application to AC-OT-SV.By comparison,we show that the AKI protocol we present is more efficient in communications than that proposed by Chow.

  7. Multi-Dimensional Top-k Dominating Queries

    DEFF Research Database (Denmark)

    Yiu, Man Lung; Mamoulis, Nikos

    2009-01-01

    attention from the research community. This paper is an extensive study on the evaluation of topk dominating queries. First, we propose a set of algorithms that apply on indexed multi-dimensional data. Second, we investigate query evaluation on data that are not indexed. Finally, we study a relaxed variant...... of the query which considers dominance in dimensional subspaces. Experiments using synthetic and real datasets demonstrate that our algorithms significantly outperform a previous skyline-based approach. We also illustrate the applicability of this multi-dimensional analysis query by studying the......The top-k dominating query returns k data objects which dominate the highest number of objects in a dataset. This query is an important tool for decision support since it provides data analysts an intuitive way for finding significant objects. In addition, it combines the advantages of top-k and...

  8. Database query optimization based on Bat Algorithm and Cuckoo Search Algorithm%基于BACS算法的数据库查询优化

    Institute of Scientific and Technical Information of China (English)

    王磊

    2015-01-01

    针对布谷鸟算法局部搜索能力弱、寻优精度低等缺陷,提出一种蝙蝠算法和布谷鸟算法相融合的数据库查询优化算法(BACS)。按照布谷鸟优化算法对鸟巢位置进行更新,利用蝙蝠算法的动态转换策略对鸟巢位置进一步更新,避免算法陷入局部最优;最后将BACS应用于数据库查询优化问题求解,并通过仿真实验对BACS的性能进行测试。实验结果表明,BACS加快了数据库查询优化求解的收敛速度,获得了质量更高的查询优化方案。%In order to solve the problems of bat algorithm which has low optimizing accuracy and weak local search ability, a novel query optimization method of database is proposed based on Bat Algorithm and Cuckoo Search Algorithm (BACS). Firstly, nest location is updated according to the cuckoo search optimization algorithm, and then cuckoo nest location is further replaced according to the dynamic conversion strategy in the bat algorithm and avoids falling into local optimum, finally it is applied to solve the query optimization problem of database, and the performance of BACS is tested by simulation experiments. The results show that, BACS accelerates the convergence speed of database query optimiza-tion and can obtain higher quality query optimization scheme.

  9. An Extensive Analysis of Query by Singing/Humming System Through Query Proportion

    Directory of Open Access Journals (Sweden)

    Trisiladevi C. Nagavi

    2013-01-01

    Full Text Available Query by Singing/Humming (QBSH is a Music Information Retrieval (MIR system with small audioexcerpt as query. The rising availability of digital music stipulates effective music retrieval methods.Further, MIR systems support content based searching for music and requires no musical acquaintance.Current work on QBSH focuses mainly on melody features such as pitch, rhythm, note etc., size ofdatabases, response time, score matching and search algorithms. Even though a variety of QBSHtechniques are proposed, there is a dearth of work to analyze QBSH through query excerption. Here, wepresent an analysis that works on QBSH through query excerpt. To substantiate a series of experiments areconducted with the help of Mel-Frequency Cepstral Coefficients (MFCC, Linear Predictive Coefficients(LPC and Linear Predictive Cepstral Coefficients (LPCC to portray the robustness of the knowledgerepresentation. Proposed experiments attempt to reveal that retrieval performance as well as precisiondiminishes in the snail phase with the growing database size.

  10. An Extensive Analysis of Query by Singing/Humming System Through Query Proportion

    Directory of Open Access Journals (Sweden)

    Trisiladevi C. Nagavi

    2012-12-01

    Full Text Available Query by Singing/Humming (QBSH is a Music Information Retrieval (MIR system with small audio excerpt as query. The rising availability of digital music stipulates effective music retrieval methods. Further, MIR systems support content based searching for music and requires no musical acquaintance. Current work on QBSH focuses mainly on melody features such as pitch, rhythm, note etc., size of databases, response time, score matching and search algorithms. Even though a variety of QBSH techniques are proposed, there is a dearth of work to analyze QBSH through query excerption. Here, we present an analysis that works on QBSH through query excerpt. To substantiate a series of experiments are conducted with the help of Mel-Frequency Cepstral Coefficients (MFCC, Linear Predictive Coefficients (LPC and Linear Predictive Cepstral Coefficients (LPCC to portray the robustness of the knowledge representation. Proposed experiments attempt to reveal that retrieval performance as well as precision diminishes in the snail phase with the growing database size.

  11. Index and query methods in road networks

    CERN Document Server

    Feng, Jun

    2015-01-01

    This book presents the index and query techniques on road network and moving objects which are limited to road network. Here, the road network of non-Euclidean space has its unique characteristics such that two moving objects may be very close in a straight line distance. The index used in two-dimensional Euclidean space is not always appropriate for moving objects on road network. Therefore, the index structure needs to be improved in order to obtain suitable indexing methods, explore the shortest path and acquire nearest neighbor query and aggregation query methods under the new index structures. Chapter 1 of this book introduces the present situation of intelligent traffic and index in road network, Chapter 2 introduces the relevant existing spatial indexing methods. Chapter 3-5 focus on several issues of road network and query, they involves: traffic road network models (see Chapter 3), index structures (see Chapter 4) and aggregate query methods (see Chapter 5). Finally, in Chapter 6, the book briefly de...

  12. Role Engagement and Anonymity in Synchronous Online Role Play

    Directory of Open Access Journals (Sweden)

    Sarah Cornelius

    2011-06-01

    Full Text Available Role play activities provide opportunities for learners to adopt unfamiliar roles, engage in interactions with others, and get involved in realistic tasks. They are often recommended to foster the development of soft skills and a wider perspective of the world. Such activities are widely used as an online teaching approach, with examples ranging from the simple use of email to the employment of virtual worlds and Web 2.0 technologies.This paper provides a case study of a role play activity which employs real-time anonymous discussion forums and aims to improve our understanding of effective role play and the impact of anonymity. This role play has been effective in educating learners about different perspectives on the issue of Quality in Further Education. The context and implementation of the role play are outlined, and the learners’ interactions and experiences are explored using an investigative analysis of discussion transcripts and semi-structured interviews with participants. The findings suggest that role engagement and anonymity are important components for success in synchronous online role play. Evidence is presented that provides an insight into the factors which encourage role engagement, including prior experiences and contributions from peers. The impact of anonymity is also explored since many participants did not regard the study environment as real and attempted to identify their peers.

  13. A Generic Framework for Anonymous Authentication in Mobile Networks

    Institute of Scientific and Technical Information of China (English)

    Jing Xu; Wen-Tao Zhu

    2013-01-01

    Designing an anonymous user authentication scheme in global mobility networks is a non-trivial task because wireless networks are susceptible to attacks and mobile devices powered by batteries have limited communication,processing and storage capabilities.In this paper,we present a generic construction that converts any existing secure password authentication scheme based on a smart card into an anonymous authentication scheme for roaming services.The security proof of our construction can be derived from the underlying password authentication scheme employing the same assumptions.Compared with the original password authentication scheme,the transformed scheme does not sacrifice the authentication efficiency,and additionally,an agreed session key can be securely established between an anonymous mobile user and the foreign agent in charge of the network being visited.Furthermore,we present an instantiation of the proposed generic construction.The performance analysis shows that compared with other related anonymous authentication schemes,our instantiation is more efficient.

  14. A note on: No need to choose: How to get both a PTAS and Sublinear Query Complexity

    CERN Document Server

    Ailon, Nir

    2012-01-01

    We revisit various PTAS's (Polynomial Time Approximation Schemes) for minimization versions of dense problems, and show that they can be performed with sublinear query complexity. This means that not only do we obtain a (1+eps)-approximation to the NP-Hard problems in polynomial time, but also avoid reading the entire input. This setting is particularly advantageous when the price of reading parts of the input is high, as is the case, for examples, where humans provide the input. Trading off query complexity with approximation is the raison d'etre of the field of learning theory, and of the ERM (Empirical Risk Minimization) setting in particular. A typical ERM result, however, does not deal with computational complexity. We discuss two particular problems for which (a) it has already been shown that sublinear querying is sufficient for obtaining a (1 + eps)-approximation using unlimited computational power (an ERM result), and (b) with full access to input, we could get a (1+eps)-approximation in polynomial t...

  15. Semantic Query Expansion Based on Multilingual Ontology%基于多语本体的语义查询扩展研究

    Institute of Scientific and Technical Information of China (English)

    司莉; 潘秋玉

    2016-01-01

    查询扩展是改善信息检索结果的有效方法。针对用户获取多语言信息的需求以及当前跨语言信息检索存在的翻译歧异性问题,提出一种基于多语本体的语义查询扩展方法,介绍其基本原理、查询扩展模型及实现过程,使跨语言信息检索从字符匹配变成语义层面的匹配,实现跨语言信息检索中的查询扩展,以提高多语言信息检索的查全率和查准率。%Query expansion is an effective method to enhance information retrieval performance. Aiming at the requirements of acquiring multilingual information and solving the problems of semantic disambiguation of cross language information retrieval (CLIR), the article proposed a new semantic query expansion method based on multilingual ontology, and introduced its fundamentals, model and realization process, to turn character-matching into semantic matching for CLIR, implementing query expansion in CLIR, which may optimize system’s recal and precision.

  16. A novel adaptive Cuckoo search for optimal query plan generation.

    Science.gov (United States)

    Gomathi, Ramalingam; Sharmila, Dhandapani

    2014-01-01

    The emergence of multiple web pages day by day leads to the development of the semantic web technology. A World Wide Web Consortium (W3C) standard for storing semantic web data is the resource description framework (RDF). To enhance the efficiency in the execution time for querying large RDF graphs, the evolving metaheuristic algorithms become an alternate to the traditional query optimization methods. This paper focuses on the problem of query optimization of semantic web data. An efficient algorithm called adaptive Cuckoo search (ACS) for querying and generating optimal query plan for large RDF graphs is designed in this research. Experiments were conducted on different datasets with varying number of predicates. The experimental results have exposed that the proposed approach has provided significant results in terms of query execution time. The extent to which the algorithm is efficient is tested and the results are documented. PMID:25215330

  17. A Novel Adaptive Cuckoo Search for Optimal Query Plan Generation

    Directory of Open Access Journals (Sweden)

    Ramalingam Gomathi

    2014-01-01

    Full Text Available The emergence of multiple web pages day by day leads to the development of the semantic web technology. A World Wide Web Consortium (W3C standard for storing semantic web data is the resource description framework (RDF. To enhance the efficiency in the execution time for querying large RDF graphs, the evolving metaheuristic algorithms become an alternate to the traditional query optimization methods. This paper focuses on the problem of query optimization of semantic web data. An efficient algorithm called adaptive Cuckoo search (ACS for querying and generating optimal query plan for large RDF graphs is designed in this research. Experiments were conducted on different datasets with varying number of predicates. The experimental results have exposed that the proposed approach has provided significant results in terms of query execution time. The extent to which the algorithm is efficient is tested and the results are documented.

  18. Goal Directed Relative Skyline Queries in Time Dependent Road Networks

    CERN Document Server

    Iyer, K B Priya

    2012-01-01

    The Wireless GIS technology is progressing rapidly in the area of mobile communications. Location-based spatial queries are becoming an integral part of many new mobile applications. The Skyline queries are latest apps under Location-based services. In this paper we introduce Goal Directed Relative Skyline queries on Time dependent (GD-RST) road networks. The algorithm uses travel time as a metric in finding the data object by considering multiple query points (multi-source skyline) relative to user location and in the user direction of travelling. We design an efficient algorithm based on Filter phase, Heap phase and Refine Skyline phases. At the end, we propose a dynamic skyline caching (DSC) mechanism which helps to reduce the computation cost for future skyline queries. The experimental evaluation reflects the performance of GD-RST algorithm over the traditional branch and bound algorithm for skyline queries in real road networks.

  19. An adaptive range-query optimization technique with distributed replicas

    Institute of Scientific and Technical Information of China (English)

    Sayar Ahmet; Pierce Marlon; Fox C.Geoffrey

    2014-01-01

    Replication is an approach often used to speed up the execution of queries submitted to a large dataset. A compile-time/run-time approach is presented for minimizing the response time of 2-dimensional range when a distributed replica of a dataset exists. The aim is to partition the query payload (and its range) into subsets and distribute those to the replica nodes in a way that minimizes a client’s response time. However, since query size and distribution characteristics of data (data dense/sparse regions) in varying ranges are not known a priori, performing efficient load balancing and parallel processing over the unpredictable workload is difficult. A technique based on the creation and manipulation of dynamic spatial indexes for query payload estimation in distributed queries was proposed. The effectiveness of this technique was demonstrated on queries for analysis of archived earthquake-generated seismic data records.

  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. 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.

  2. Querying Big Data:Bridging Theory and Practice

    Institute of Scientific and Technical Information of China (English)

    樊文飞; 怀进鹏

    2014-01-01

    Big data introduces challenges to query answering, from theory to practice. A number of questions arise. What queries are “tractable” on big data? How can we make big data “small” so that it is feasible to find exact query answers? When exact answers are beyond reach in practice, what approximation theory can help us strike a balance between the quality of approximate query answers and the costs of computing such answers? To get sensible query answers in big data, what else do we necessarily do in addition to coping with the size of the data? This position paper aims to provide an overview of recent advances in the study of querying big data. We propose approaches to tackling these challenging issues, and identify open problems for future research.

  3. Querying and Extracting Timeline Information from Road Traffic Sensor Data.

    Science.gov (United States)

    Imawan, Ardi; Indikawati, Fitri Indra; Kwon, Joonho; Rao, Praveen

    2016-08-23

    The escalation of traffic congestion in urban cities has urged many countries to use intelligent transportation system (ITS) centers to collect historical traffic sensor data from multiple heterogeneous sources. By analyzing historical traffic data, we can obtain valuable insights into traffic behavior. Many existing applications have been proposed with limited analysis results because of the inability to cope with several types of analytical queries. In this paper, we propose the QET (querying and extracting timeline information) system-a novel analytical query processing method based on a timeline model for road traffic sensor data. To address query performance, we build a TQ-index (timeline query-index) that exploits spatio-temporal features of timeline modeling. We also propose an intuitive timeline visualization method to display congestion events obtained from specified query parameters. In addition, we demonstrate the benefit of our system through a performance evaluation using a Busan ITS dataset and a Seattle freeway dataset.

  4. Querying and Extracting Timeline Information from Road Traffic Sensor Data

    Directory of Open Access Journals (Sweden)

    Ardi Imawan

    2016-08-01

    Full Text Available The escalation of traffic congestion in urban cities has urged many countries to use intelligent transportation system (ITS centers to collect historical traffic sensor data from multiple heterogeneous sources. By analyzing historical traffic data, we can obtain valuable insights into traffic behavior. Many existing applications have been proposed with limited analysis results because of the inability to cope with several types of analytical queries. In this paper, we propose the QET (querying and extracting timeline information system—a novel analytical query processing method based on a timeline model for road traffic sensor data. To address query performance, we build a TQ-index (timeline query-index that exploits spatio-temporal features of timeline modeling. We also propose an intuitive timeline visualization method to display congestion events obtained from specified query parameters. In addition, we demonstrate the benefit of our system through a performance evaluation using a Busan ITS dataset and a Seattle freeway dataset.

  5. Disjunctive ASP with Functions: Decidable Queries and Effective Computation

    CERN Document Server

    Alviano, Mario; Leone, Nicola; 10.1017/S1471068410000244

    2010-01-01

    Querying over disjunctive ASP with functions is a highly undecidable task in general. In this paper we focus on disjunctive logic programs with stratified negation and functions under the stable model semantics (ASP^{fs}). We show that query answering in this setting is decidable, if the query is finitely recursive (ASP^{fs}_{fr}). Our proof yields also an effective method for query evaluation. It is done by extending the magic set technique to ASP^{fs}_{fr}. We show that the magic-set rewritten program is query equivalent to the original one (under both brave and cautious reasoning). Moreover, we prove that the rewritten program is also finitely ground, implying that it is decidable. Importantly, finitely ground programs are evaluable using existing ASP solvers, making the class of ASP^{fs}_{fr} queries usable in practice.

  6. Querying and Extracting Timeline Information from Road Traffic Sensor Data.

    Science.gov (United States)

    Imawan, Ardi; Indikawati, Fitri Indra; Kwon, Joonho; Rao, Praveen

    2016-01-01

    The escalation of traffic congestion in urban cities has urged many countries to use intelligent transportation system (ITS) centers to collect historical traffic sensor data from multiple heterogeneous sources. By analyzing historical traffic data, we can obtain valuable insights into traffic behavior. Many existing applications have been proposed with limited analysis results because of the inability to cope with several types of analytical queries. In this paper, we propose the QET (querying and extracting timeline information) system-a novel analytical query processing method based on a timeline model for road traffic sensor data. To address query performance, we build a TQ-index (timeline query-index) that exploits spatio-temporal features of timeline modeling. We also propose an intuitive timeline visualization method to display congestion events obtained from specified query parameters. In addition, we demonstrate the benefit of our system through a performance evaluation using a Busan ITS dataset and a Seattle freeway dataset. PMID:27563900

  7. A Novel Adaptive Cuckoo Search for Optimal Query Plan Generation

    OpenAIRE

    Ramalingam Gomathi; Dhandapani Sharmila

    2014-01-01

    The emergence of multiple web pages day by day leads to the development of the semantic web technology. A World Wide Web Consortium (W3C) standard for storing semantic web data is the resource description framework (RDF). To enhance the efficiency in the execution time for querying large RDF graphs, the evolving metaheuristic algorithms become an alternate to the traditional query optimization methods. This paper focuses on the problem of query optimization of semantic web data. An efficient ...

  8. 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

  9. 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.

  10. 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. PMID:24724731

  11. 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...... facilities are inadequate. The Visual Model Query Language (VMQL) is a novel approach that uses the respective modeling language of the source model as the query language, too. The semantics of VMQL is defined formally based on graphs, so that query execution can be defined as graph matching. VMQL has been...... applied to several visual modeling languages, implemented, and validated in small case studies, and several controlled experiments....

  12. Anonimos: An LP based Approach for Anonymizing Weighted Social Network Graphs

    CERN Document Server

    Das, Sudipto; Abbadi, Amr El

    2010-01-01

    The increasing popularity of social networks has initiated a fertile research area in information extraction and data mining. Anonymization of these social graphs is important to facilitate publishing these data sets for analysis by external entities. Prior work has concentrated mostly on node identity anonymization and structural anonymization. But with the growing interest in analyzing social networks as a weighted network, edge weight anonymization is also gaining importance. We present An\\'onimos, a Linear Programming based technique for anonymization of edge weights that preserves linear properties of graphs. Such properties form the foundation of many important graph-theoretic algorithms such as shortest paths problem, k-nearest neighbors, minimum cost spanning tree, and maximizing information spread. As a proof of concept, we apply An\\'onimos to the shortest paths problem and its extensions, prove the correctness, analyze complexity, and experimentally evaluate it using real social network data sets. O...

  13. Automatic Building Information Model Query Generation

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Yufei; Yu, Nan; Ming, Jiang; Lee, Sanghoon; DeGraw, Jason; Yen, John; Messner, John I.; Wu, Dinghao

    2015-12-01

    Energy efficient building design and construction calls for extensive collaboration between different subfields of the Architecture, Engineering and Construction (AEC) community. Performing building design and construction engineering raises challenges on data integration and software interoperability. Using Building Information Modeling (BIM) data hub to host and integrate building models is a promising solution to address those challenges, which can ease building design information management. However, the partial model query mechanism of current BIM data hub collaboration model has several limitations, which prevents designers and engineers to take advantage of BIM. To address this problem, we propose a general and effective approach to generate query code based on a Model View Definition (MVD). This approach is demonstrated through a software prototype called QueryGenerator. By demonstrating a case study using multi-zone air flow analysis, we show how our approach and tool can help domain experts to use BIM to drive building design with less labour and lower overhead cost.

  14. Animating the Web with jQuery

    Directory of Open Access Journals (Sweden)

    Asokan M

    2013-02-01

    Full Text Available World globalization and present day technology increases the web users rapidly. Every website is trying to attract the web users. The web site creators /developers add different kind of animations to their websites. There are many softwares available to create animation. jQuery can be used to create interactive and powerful web pages with animations. JQuery is a JavaScript library intendedto make Java Script programming easier and more fun. A JavaScript library is a complex JavaScript program that both simplifies difficult tasks and solves cross-browser problems. With jQuery, we canaccomplish tasks in a single line of code. JQuery is used on millions of websites. This paper discuss about the advantages and usage statistics of jQuery on the web. A complete procedure to create a slider and banner plug-ins are also included. They are tested with different browsers.

  15. Web Database Schema Identification through Simple Query Interface

    Science.gov (United States)

    Lin, Ling; Zhou, Lizhu

    Web databases provide different types of query interfaces to access the data records stored in the backend databases. While most existing works exploit a complex query interface with multiple input fields to perform schema identification of the Web databases, little attention has been paid on how to identify the schema of web databases by simple query interface (SQI), which has only one single query text input field. This paper proposes a new method of instance-based query probing to identify WDBs' interface and result schema for SQI. The interface schema identification problem is defined as generating the fullcondition query of SQI and a novel query probing strategy is proposed. The result schema is also identified based on the result webpages of SQI's full-condition query, and an extended identification of the non-query attributes is proposed to improve the attribute recall rate. Experimental results on web databases of online shopping for book, movie and mobile phone show that our method is effective and efficient.

  16. Usability of XML Query Languages

    NARCIS (Netherlands)

    Graaumans, J.P.M.

    2005-01-01

    The eXtensible Markup Language (XML) is a markup language which enables re-use of information. Specific query languages for XML are developed to facilitate this. There are large differences between history, design goal, and syntax of the XML query languages. However, in practice these languages are

  17. The Semantics of Query Modification

    NARCIS (Netherlands)

    Hollink, V.; Tsikrika, T.; Vries, A.P. de

    2010-01-01

    We present a method that exploits `linked data' to determine semantic relations between consecutive user queries. Our method maps queries onto concepts in linked data and searches the linked data graph for direct or indirect relations between the concepts. By comparing relations between large number

  18. Priming the Query Specification Process.

    Science.gov (United States)

    Toms, Elaine G.; Freund, Luanne

    2003-01-01

    Tests the use of questions as a technique in the query specification process. Using a within-subjects design, 48 people interacted with a modified Google interface to solve four information problems in four domains. Half the tasks were entered as typical keyword queries, and half as questions or statements. Results suggest the typical search box…

  19. How Alcoholics Anonymous (AA) and Narcotics Anonymous (NA) Work: Cross-Disciplinary Perspectives

    OpenAIRE

    Krentzman, Amy R.; Robinson, Elizabeth A. R.; Moore, Barbara C.; Kelly, John F.; Laudet, Alexandre B.; White, William L.; Zemore, Sarah E.; Kurtz, Ernest; Strobbe, Stephen

    2010-01-01

    Evidence from multiple lines of research supports the effectiveness and practical importance of Alcoholics Anonymous and Narcotics Anonymous. Conference presenters discussed the relationship between 12-Step participation and abstinence among various populations, including adolescents, women, and urban drug users. Insight from the arts and humanities placed empirical findings in a holistic context.

  20. How Alcoholics Anonymous (AA) and Narcotics Anonymous (NA) Work: Cross-Disciplinary Perspectives.

    Science.gov (United States)

    Krentzman, Amy R; Robinson, Elizabeth A R; Moore, Barbara C; Kelly, John F; Laudet, Alexandre B; White, William L; Zemore, Sarah E; Kurtz, Ernest; Strobbe, Stephen

    2010-12-01

    Evidence from multiple lines of research supports the effectiveness and practical importance of Alcoholics Anonymous and Narcotics Anonymous. Conference presenters discussed the relationship between 12-Step participation and abstinence among various populations, including adolescents, women, and urban drug users. Insight from the arts and humanities placed empirical findings in a holistic context. PMID:21785524

  1. Annotating URLs with query terms: What factors predict reliable annotations?

    OpenAIRE

    Verberne, S.; Hinne, M.; van der Heijden, M.; Kraaij, Wessel; D'hondt, E.K.L.; Weide, Theo van der

    2009-01-01

    A number of recent studies have investigated the relation be-ween URLs and associated query terms from search engine log files. In [5], the query terms associated with the domain of a URL were used as features for a URL classification task. The idea is that query terms that lead to successful classification of a URL are reliable semantic descriptors of the URL content. We follow up on this work by investigating which properties of a URL and its associated query terms predict the classificatio...

  2. Metadata Challenge for Query Processing Over Heterogeneous Wireless Sensor Network

    CERN Document Server

    Komalavalli, C

    2011-01-01

    Wireless sensor networks become integral part of our life. These networks can be used for monitoring the data in various domain due to their flexibility and functionality. Query processing and optimization in the WSN is a very challenging task because of their energy and memory constraint. In this paper, first our focus is to review the different approaches that have significant impacts on the development of query processing techniques for WSN. Finally, we aim to illustrate the existing approach in popular query processing engines with future research challenges in query optimization.

  3. Performance evaluation of various K- anonymity techniques

    Science.gov (United States)

    Maheshwarkar, Nidhi; Pathak, Kshitij; Chourey, Vivekanand

    2011-12-01

    Today's advanced scenario where each information is available in one click, data security is the main aspect. Individual information which sometimes needs to be hiding is easily available using some tricks. Medical information, income details are needed to be kept away from adversaries and so, are stored in private tables. Some publicly released information contains zip code, sex, birth date. When this released information is linked with the private table, adversary can detect the whole confidential information of individuals or respondents, i.e. name, medical status. So to protect respondents identity, a new concept k-anonymity is used which means each released record has at least (k-1) other records in the release whose values are distinct over those fields that appear in the external data. K-anonymity can be achieved easily in case of single sensitive attributes i.e. name, salary, medical status, but it is quiet difficult when multiple sensitive attributes are present. Generalization and Suppression are used to achieve k-anonymity. This paper provides a formal introduction of k-anonymity and some techniques used with it l-diversity, t-closeness. This paper covers k-anonymity model and the comparative study of these concepts along with a new proposed concept for multiple sensitive attributes.

  4. Query Load Balancing For Visible Object Extraction

    DEFF Research Database (Denmark)

    Bukauskas, Linas; Bøhlen, Michael Hanspeter

    2004-01-01

    Interactive visual data explorations impose rigid real-time requirements on the extraction of visible objects. Often these requirements are met by deploying powerful hardware that maintains the entire data set in huge main memory structures. In this paper we propose an approach that retrieves the...... point path method minimizes the number of queries by permitting larger query results. The experimental results show that our implementation reduces the number of I/O operations significantly, is stable, and does not depend on the initial number of path points....

  5. 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

  6. Query strategy for sequential ontology debugging

    CERN Document Server

    Shchekotykhina, Kostyantyn; Fleiss, Philipp; Rodler, Patrick

    2011-01-01

    Debugging of ontologies is an important prerequisite for their wide-spread application, especially in areas that rely upon everyday users to create and maintain knowledge bases, as in the case of the Semantic Web. Recent approaches use diagnosis methods to identify causes of inconsistent or incoherent ontologies. However, in most debugging scenarios these methods return many alternative diagnoses, thus placing the burden of fault localization on the user. This paper demonstrates how the target diagnosis can be identified by performing a sequence of observations, that is, by querying an oracle about entailments of the target ontology. We exploit a-priori probabilities of typical user errors to formulate information-theoretic concepts for query selection. Our evaluation showed that the proposed method significantly reduces the number of required queries compared to myopic strategies. We experimented with different probability distributions of user errors and different qualities of the a-priori probabilities. Ou...

  7. Optimal Planar Orthogonal Skyline Counting Queries

    DEFF Research Database (Denmark)

    Brodal, Gerth Stølting; Larsen, Kasper Green

    2014-01-01

    The skyline of a set of points in the plane is the subset of maximal points, where a point (x,y) is maximal if no other point (x',y') satisfies x'≥ x and y'≥ x. We consider the problem of preprocessing a set P of n points into a space efficient static data structure supporting orthogonal skyline...... 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...

  8. Querying dynamic communities in online social networks

    Institute of Scientific and Technical Information of China (English)

    Li WEIGANG; Edans F.O.SANDES; Jianya ZHENG; Alba C.M.A.de MELO; Lorna UDEN

    2014-01-01

    Online social networks (OSNs) offer people the opportunity to join communities where they share a common interest or objective. This kind of community is useful for studying the human behavior, diffusion of information, and dynamics of groups. As the members of a community are always changing, an efficient solution is needed to query information in real time. This paper introduces the Follow Model to present the basic relationship between users in OSNs, and combines it with the MapReduce solution to develop new algorithms with parallel paradigms for querying. Two models for reverse relation and high-order relation of the users were implemented in the Hadoop system. Based on 75 GB message data and 26 GB relation network data from Twitter, a case study was realized using two dynamic discussion communities:#musicmonday and #beatcancer. The querying performance demonstrates that the new solution with the implementation in Hadoop significantly improves the ability to find useful information from OSNs.

  9. Transfer active learning by querying committee

    Institute of Scientific and Technical Information of China (English)

    Hao SHAO; Feng TAO; Rui XU

    2014-01-01

    In real applications of inductive learning for classifi cation, labeled instances are often defi cient, and labeling them by an oracle is often expensive and time-consuming. Active learning on a single task aims to select only informative unlabeled instances for querying to improve the classifi cation accuracy while decreasing the querying cost. However, an inevitable problem in active learning is that the informative measures for selecting queries are commonly based on the initial hypotheses sampled from only a few labeled instances. In such a circumstance, the initial hypotheses are not reliable and may deviate from the true distribution underlying the target task. Consequently, the informative measures will possibly select irrelevant instances. A promising way to compensate this problem is to borrow useful knowledge from other sources with abundant labeled information, which is called transfer learning. However, a signifi cant challenge in transfer learning is how to measure the similarity between the source and the target tasks. One needs to be aware of different distributions or label assignments from unrelated source tasks;otherwise, they will lead to degenerated performance while transferring. Also, how to design an effective strategy to avoid selecting irrelevant samples to query is still an open question. To tackle these issues, we propose a hybrid algorithm for active learning with the help of transfer learning by adopting a divergence measure to alleviate the negative transfer caused by distribution differences. To avoid querying irrelevant instances, we also present an adaptive strategy which could eliminate unnecessary instances in the input space and models in the model space. Extensive experiments on both the synthetic and the real data sets show that the proposed algorithm is able to query fewer instances with a higher accuracy and that it converges faster than the state-of-the-art methods.

  10. 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.

  11. a-diversity and k-anonymity Big Data Privacy Preservation Based on Micro-aggregation%基于微聚集的a-多样性k-匿名大数据隐私保护

    Institute of Scientific and Technical Information of China (English)

    程亮; 蒋凡

    2015-01-01

    基于敏感信息的数据发布面临的主要问题在于如何保证数据的有用性和隐私保护。匿名化是一个很好的方法,目前有多种匿名化模型。然而大多数的模型主要侧重于使用预先定义的参数为整个数据集提供无差别的隐私保护,这并不能适应不同个体对不同敏感属性的多样性保护需求。基于此,文章提出了一种满足敏感信息的多样性非相关约束的a-多样性 k-匿名化模型;同时,设计了一个改进的微聚集算法的框架替代了传统的泛化/抑制实现匿名化。使用这个框架,能够提高数据的有用性并降低隐私泄露的风险。通过在真实数据集上进行多次试验验证了此方案的有效性。%A great challenge in privacy preservation is to trade off two important issues: data utility and privacy preservation, in publication of dataset which usually contain sensitive information. Anonymization is a well-represent approach to achieve this, and there exist several anonymity models. Most of those models mainly focus on protecting privacy exerting identical protection for the whole table with pre-deifned parameters. This could not meet the diverse requirements of protection degrees varied with different sensitive value. Motivated by this, this paper firstly proposes an a-diversity k-anonymity model to satisfy diversity deassociation for sensitive information, and meanwhile, designs a framework based on an improved microaggregation algorithm, as an alternative to generalization/suppression to achieve anonymization. By using this framework, we improve the data utility and decrease the disclosure risk of privacy disclosure. We conduct several experiments to validate our schemes.

  12. Anonymity-Preserving Public-Key Encryption

    DEFF Research Database (Denmark)

    Kohlweiss, Markulf; Maurer, Ueli; Onete, Cristina;

    2013-01-01

    . While anonymity and confidentiality appear to be orthogonal properties, making anonymous communication confidential is more involved than one might expect, since the ciphertext might reveal which public key has been used to encrypt. To address this problem, public-key cryptosystems with enhanced...... 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...

  13. 基于UDT协议的印章查询系统%Seal querying system based on UDT protocol

    Institute of Scientific and Technical Information of China (English)

    张帝; 张宇

    2011-01-01

    鉴于TCP协议的低效性和UDP协议的不可靠性,提出一种运用了新的可靠UDP协议(UDT)的印章查询系统,大大提高了数据传输的可靠性,同时引入Tinyxml以及Zlib技术来实现印章查询的功能.由于采用新的数据传输协议,并引入相应的拥塞控制和数据可靠性控制机制,使得印章查询系统的效率能够满足用户的需求.%Concerning the inefficiency of TCP protocol and the unreliability of UDP protocol, the seal querying system with a novel and reliable UDP protocol (UDT), greatly increased the reliability of data transmission, and achieved its seal querying function by applying the technology of Tinyxml and Zlib. Due to the employment of the new data transfer protocol and relevant congestion control and data reliability mechanism, the users' needs can be greatly met with the efficiency of the proposed system.

  14. Query and document models for enterprise search

    NARCIS (Netherlands)

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

    2007-01-01

    We describe our participation in the TREC 2007 Enterprise track and detail our language modeling-based approaches. For document search, our focus was on estimating a mixture model using a standard web collection, and on constructing query models by employing blind relevance feedback and using the ex

  15. SEMANTIC WEB (CREATING AND QUERYING

    Directory of Open Access Journals (Sweden)

    Vidya S. Dandagi

    2016-01-01

    Full Text Available Semantic Web is a system that allows machines to understand complex human requests. Depending on the meaning semantic web replies. Semantics is the learning of the meanings of linguistic appearance. It is the main branch of contemporary linguistics. Semantics is meaning of words, text or a phrase and relations between them. RDF provides essential support to the Semantic Web. To represent distributed information RDF is created. Applications can use RDF created and process it in an adaptive manner. Knowledge representation is done using RDF standards and it is machine understandable. This paper describes the creation of a semantic web using RDF, and retrieval of accurate results using SparQL query language.

  16. 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...

  17. 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.

  18. Querying Semi-Structured Data

    Science.gov (United States)

    Abiteboul, Serge

    1997-01-01

    The amount of data of all kinds available electronically has increased dramatically in recent years. The data resides in different forms, ranging from unstructured data in the systems to highly structured in relational database systems. Data is accessible through a variety of interfaces including Web browsers, database query languages, application-specic interfaces, or data exchange formats. Some of this data is raw data, e.g., images or sound. Some of it has structure even if the structure is often implicit, and not as rigid or regular as that found in standard database systems. Sometimes the structure exists but has to be extracted from the data. Sometimes also it exists but we prefer to ignore it for certain purposes such as browsing. We call here semi-structured data this data that is (from a particular viewpoint) neither raw data nor strictly typed, i.e., not table-oriented as in a relational model or sorted-graph as in object databases. As will seen later when the notion of semi-structured data is more precisely de ned, the need for semi-structured data arises naturally in the context of data integration, even when the data sources are themselves well-structured. Although data integration is an old topic, the need to integrate a wider variety of data- formats (e.g., SGML or ASN.1 data) and data found on the Web has brought the topic of semi-structured data to the forefront of research. The main purpose of the paper is to isolate the essential aspects of semi- structured data. We also survey some proposals of models and query languages for semi-structured data. In particular, we consider recent works at Stanford U. and U. Penn on semi-structured data. In both cases, the motivation is found in the integration of heterogeneous data.

  19. Tracking Federated Queries in the Linked Data

    OpenAIRE

    Nassopoulos, Georges; Serrano-Alvarado, Patricia; Molli, Pascal; Desmontils, Emmanuel

    2015-01-01

    Federated query engines allow data consumers to execute queries over the federation of Linked Data (LD). However, as feder-ated queries are decomposed into potentially thousands of subqueries distributed among SPARQL endpoints, data providers do not know fed-erated queries, they only know subqueries they process. Consequently, unlike warehousing approaches, LD data providers have no access to secondary data. In this paper, we propose FETA (FEderated query TrAcking), a query tracking algorithm...

  20. Study of query expansion techniques and their application in the biomedical information retrieval.

    Science.gov (United States)

    Rivas, A R; Iglesias, E L; Borrajo, L

    2014-01-01

    Information Retrieval focuses on finding documents whose content matches with a user query from a large document collection. As formulating well-designed queries is difficult for most users, it is necessary to use query expansion to retrieve relevant information. Query expansion techniques are widely applied for improving the efficiency of the textual information retrieval systems. These techniques help to overcome vocabulary mismatch issues by expanding the original query with additional relevant terms and reweighting the terms in the expanded query. In this paper, different text preprocessing and query expansion approaches are combined to improve the documents initially retrieved by a query in a scientific documental database. A corpus belonging to MEDLINE, called Cystic Fibrosis, is used as a knowledge source. Experimental results show that the proposed combinations of techniques greatly enhance the efficiency obtained by traditional queries.

  1. 基于本体的语义查询扩展应用研究%Application Research of Semantic Query Expansion Based on Ontology

    Institute of Scientific and Technical Information of China (English)

    王红霞

    2016-01-01

    传统的基于关键词匹配的信息检索方式已无法满足智慧城市建设进程中海量数据处理的要求,而基于本体的语义查询扩展智能化搜索技术借助于本体的语义信息与扩展推理使查询条件更符合用户意图,能够提高查全率和查准率,优化检索结果.在本体语义查询扩展技术的研究基础上,使用主流的本体编辑工具Protégé创建了一个"计算机"领域的本体,并根据现实需要进行规则修改,最终将其应用于智慧城市远程教育资源的个性化搜索中,能取得较理想的效果.%With the rapid development of smart city, the traditional search method based on key words can 't satisfy users. Semantic query expansion based on ontology is an important intelligent search technique which with the help of semantic information and expansion reasoning. The precision and recall can be improved and the research result can be optimized. This article studies carefully the semantic query expansion theory, built domain ontology of the computer science based on Protégé and Chinese Library Classification. In the same way, the rules are modified according to the reality. Eventually, the query expansion was used to distance education resources of smart city for personalized search with good effect.

  2. Cooperative Scalable Moving Continuous Query Processing

    DEFF Research Database (Denmark)

    Li, Xiaohui; Karras, Panagiotis; Jensen, Christian S.

    2012-01-01

    A range of applications call for a mobile client to continuously monitor others in close proximity. Past research on such problems has covered two extremes: It has offered totally centralized solutions, where a server takes care of all queries, and totally distributed solutions, in which there is...

  3. Approximate Nearest Neighbor Queries among Parallel Segments

    DEFF Research Database (Denmark)

    Emiris, Ioannis Z.; Malamatos, Theocharis; Tsigaridas, Elias

    2010-01-01

    We develop a data structure for answering efficiently approximate nearest neighbor queries over a set of parallel segments in three dimensions. We connect this problem to approximate nearest neighbor searching under weight constraints and approximate nearest neighbor searching on historical data...

  4. Anonymity control in electronic check systems

    Institute of Scientific and Technical Information of China (English)

    Ma Chunguang; Yang Yixian; Hu Zhengming

    2005-01-01

    Electronic check systems, as one of electronic payment systems, are more desirable than other electronic cash systems. In the system, only a single check is used to pay any price that is not more than the face value. The main problem in check systems is to design an efficient refund mechanism that makes refund checks undistinguished from initial checks during payment and deposit. The problem of anonymity control also called fairness is also an important issue in check systems. All check systems yet are unconditional anonymity that opens the door to misuse for crime such as laundering and blackmailing. In this paper, the notion of anonymity revocation is introduced to electronic check system for the first time, and a model of fair electronic check system is proposed. An efficient fair online electronic check system with reusable refund is presented. In the system, a passive trustee is employed to revoke the anonymity of un-honest users. Moreover, the system solves the reusability problem of refunds thanks to the RSA-based partially signature. The system is efficient and meets all basic security requirements.

  5. Secure Web Transaction with Anonymous Mobile Agent over Internet

    Institute of Scientific and Technical Information of China (English)

    WANG ChangJie(王常杰); ZHANG FangGuo(张方国); WANG YuMin(王育民)

    2003-01-01

    A major problem of mobile agents is their apparent inability to authenticate transactions in hostile environments. In this paper, a new secure anonymous mobile agent scheme is proposed for the prevention of agent tempering without compromising the mobility or autonomy of the agent. In the scheme, a mobile agent can produce valid signature on website's bid (it means to transact a contact with the web site) on behalf of its customer, without revealing the customer's real private key. In addition, the anonymity of the customer is also achieved when its agent transacts with the websites. Furthermore, the customer who issues a malicious agent or denies the transaction can be identified and detected by Agent Management Center (AMC). Therefore, the scheme is practical in the future electronic commerce over Internet.

  6. 基于全文检索的XML存储查询系统%STORING AND QUERYING SYSTEM FOR XML BASED ON FULL TEXT RETRIEVAL

    Institute of Scientific and Technical Information of China (English)

    乔长昭; 廖畅

    2011-01-01

    XML database has been an important part of the field of databases, but its business products are put into effect mainly based on the relational databases,which definitely bring in some troubles. Facing the situation of storing XML data in relational databases,a new XML index code is provided, with which the problem of integrating full text retrieval technology and XML structural join querying in relational databases is resolved, and XML querying can be expedited with the help of full text retrieval. The solution is used in an actual software developing program which has well dealt with the management of relational database store of XML documents and shows a good querying efficiency.%XML数据库已经成为数据库领域的重要成员,但是在商业数据库产品中它主要构建在关系数据库基础之上,这自然引入很多难题.针对XML的关系数据库存储,提出一种新的XML索引编码,解决了在关系数据库中集成全文检索技术和XML结构连接查询算法的问题,同时借助全文检索技术达到XML查询加速的效果.该方案应用于实际软件开发项目中.很好地解决了XML文档的关系数据库存储管理工作,并且具有很高的查询效率.

  7. Design of Database Query Software of Shortwave Signals based on Python%基于Python的短波信号数据库查询软件设计

    Institute of Scientific and Technical Information of China (English)

    刘燕; 王磊

    2015-01-01

    The number of radio communication is becoming larger, and the databases of corresponding supervision department are constantly being updated, in order to improve the speed of querying databases and the monitoring efficiency, combined with daily monitoring work experience and used the existing databases of shortwave signals, this paper researches and designs the software for querying database based on Python programming language. This paper introduces the advantages of Python and the design process of this software in detail. And applies the existing databases of shortwave signals, we did a lot of test and veriifed the software’s practicability and high efifciency. The software also can query the databases of other types of radio signals and help to improve work efifciency.%无线电通信数量日益增多,其监管部门的数据库也在不断更新,为提高数据库查询速度,提高监测工作效率,本文基于Python程序设计语言,结合实际工作,针对短波通信信号数据库设计实现了一款数据库查询软件。文章详细介绍了Python语言的优势及数据库查询软件的设计流程,且使用现有的短波信号数据库进行反复测试,验证了其实用性与高效性。该软件也可以应用在其他无线电信号数据库查询工作中,对提高工作效率有一定的帮助。

  8. 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...

  9. 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…

  10. Employee Anonymous Online Dissent: Dynamics and Ethical Challenges for Employees, Targeted Organisations, Online Outlets and Audiences

    DEFF Research Database (Denmark)

    Ravazzani, Silvia; Mazzei, Alessandra

    2015-01-01

    This paper aims to enhance understanding of dissent expressive acts that employees voice via anonymous online public contexts. Based on literature on organisational dissent, anonymity and online disclosure, we first point out key dynamics of employee anonymous online dissent, and then present...... remaining accountable for them and avoiding emotion-focused and defensive disclosure. Targeted organisations need to prevent external disclosure while ensuring freedom of speech and employee privacy, and to respond effectively when overt criticism is found online. Other tensions concern online outlet...

  11. 基于异构双极信息的模糊查询研究%Study on Fuzzy Query of Heterogeneous Bipolarity Information

    Institute of Scientific and Technical Information of China (English)

    赵法信; 金义富

    2013-01-01

    在日常生活中,人们在表达其需求时,常常会对同一事物同时使用正面的描述和负面的描述.由于不要求正、负面的描述必须相互对称,此类具有异构语义的信息被称为异构双极信息.传统信息系统中的模糊查询方法,不能很好地处理用户查询需求中所含有的异构双极信息.基于经典数据库,以在模糊查询中能够处理异构双极信息为目标,将Vague集引入到异构双极信息的建模,给出了一个由独立的满意度和不满意度所组成的异构双极信息查询满意度模型框架,并在此基础上讨论了包含正面、负面信息的异构双极信息查询处理方法.%In daily life,people often give both positive and negative information to state what they desire and what they reject for the same things.Because positive and negative statements do not necessarily mirror each other,this results in so-called heterogeneous bipolar information.The fuzzy query in traditional information systemss does not adequately support the handling of heterogeneous bipolar information.In this paper,based on the regular database,vague set was introduced into the modeling of heterogeneous bipolar information for dealing with heterogeneous bipolar information in fuzzy queries,and a bipolar query satisfaction modelling framework which is based on couples that consist of an independent degree of satisfaction and degree of dissatisfaction was given,then the processing of heterogeneous bipolar queries that contain both positive and negative criteria was also discussed.

  12. 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

  13. 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...

  14. Accountable Anonymous Service Usage in Mobile Communication Systems

    OpenAIRE

    Buttyan, Levente; Hubaux, Jean-Pierre

    1999-01-01

    We introduce a model that allows of anonymous yet accountable service usage in mobile communication systems. This model is based on the introduction of a new business role, called the customer care agency, and a ticket based mechanism for service access. We motivate the introduction of customer care agencies by analyzing their role and emphasizing their advantages. We introduce the general idea of ticket based service access, present a categorization of ticket types and ticket acquisi...

  15. Anonymity in a Limit-Order Market: An Experimental Analysis

    OpenAIRE

    Majois, Christophe

    2008-01-01

    In this paper, we adopt an experimental approach to evaluate the impact of pre-trade anonymity in order-driven markets. More specifically, we build an experimental design of an electronic limit-order market, and compare two settings: one in which traders observe the identities of agents placing orders in the order book, and the other one where this information is not available on market screens. We find that ID code disclosure does not alter liquidity, efficiency or traders’ pr...

  16. Guaranteeing anonymity when sharing medical data, the Datafly System.

    OpenAIRE

    Sweeney, L.

    1997-01-01

    We present a computer program named Datafly that maintains anonymity in medical data by automatically generalizing, substituting, and removing information as appropriate without losing many of the details found within the data. Decisions are made at the field and record level at the time of database access, so the approach can be used on the fly in role-based security within an institution, and in batch mode for exporting data from an institution. Often organizations release and receive medic...

  17. Enhancing Censorship Resistance in the Tor Anonymity Network

    OpenAIRE

    Winter, Philipp

    2014-01-01

    Baksidestext The Tor network was originally designed as low-latency anonymity network.However, as the years progressed, Tor earned a reputation as also being a useful tool to circumvent Internet censorship. At times, the network counted 30,000 users only from China. Censors reacted by tightening their grip on the national communication infrastructure. In particular, they developed techniques to prevent people from being able to access the Tor network. This arms race now counts several iterati...

  18. XPath Query Completeness Verification Algorithms in DAS

    Directory of Open Access Journals (Sweden)

    Xiaoyuan Bao

    2010-10-01

    Full Text Available With the development in the application environment of database management system, the related technologies such as data management and data access have become more and more complex and the cost of maintenance has been more and more expensive. The problems that how to enable enterprises to focus on their expert areas and outsource the unfamiliar enterprise information systems to others, thus to save a lot of resources but receive the same quality of services, are widely concerned by the database research and application areas. Database as a service (DAS, which means that enterprises outsource the database system to some database service providers (DSP who manage the massive data and provide high-quality data management service becomes an important application in nowadays. To enjoy services provided by a third party, we need to ensure the correctness and completeness of query results. This paper pospose an algorithm which provides an authentication method for the  query results returned from a possible malicous server on which database is outsourced and query is evaluated. The basic idea is to build some Merkle hash trees twice to verify the correctness and completeness of the query results. We have demonstrated the effectiveness of our method in experiments.

  19. A new approach to query expansion in information retrieval

    Institute of Scientific and Technical Information of China (English)

    Li Weijiang; Zhao Tiejun; Wang Xiangang

    2008-01-01

    To eliminate the mismatch between words of relevant documents and user's query and more serious negative effects it has on the performance of information retrieval,a method of query expansion on the basis of new terms co-occurrence representation was put forward by analyzing the process of producing query. The expansion terms were selected according to their correlation to the whole query. At the same time, the position information between terms were considered. The experimental result on test retrieval conference (TREC) data collection shows that the method proposed in the paper has made an improvement of 5%~19% all the time than the language modeling method without expansion. Compared to the popular approach of query expansion, pseudo feedback, the precision of the proposed method is competitive.

  20. Anonymous Card Shuffling and its Applications to Parallel Mixnets

    CERN Document Server

    Goodrich, Michael T

    2012-01-01

    We study the question of how to shuffle $n$ cards when faced with an opponent who knows the initial position of all the cards {\\em and} can track every card when permuted, {\\em except} when one takes $K< n$ cards at a time and shuffles them in a private buffer "behind your back," which we call {\\em buffer shuffling}. The problem arises naturally in the context of parallel mixnet servers as well as other security applications. Our analysis is based on related analyses of load-balancing processes. We include extensions to variations that involve corrupted servers and adversarially injected messages, which correspond to an opponent who can peek at some shuffles in the buffer and who can mark some number of the cards. In addition, our analysis makes novel use of a sum-of-squares metric for anonymity, which leads to improved performance bounds for parallel mixnets and can also be used to bound well-known existing anonymity measures.

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

    Science.gov (United States)

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

    2016-06-01

    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.

  2. Compromising Tor Anonymity Exploiting P2P Information Leakage

    CERN Document Server

    Manils, Pere; Blond, Stevens Le; Kaafar, Mohamed Ali; Castelluccia, Claude; Legout, Arnaud; Dabbous, Walid

    2010-01-01

    Privacy of users in P2P networks goes far beyond their current usage and is a fundamental requirement to the adoption of P2P protocols for legal usage. In a climate of cold war between these users and anti-piracy groups, more and more users are moving to anonymizing networks in an attempt to hide their identity. However, when not designed to protect users information, a P2P protocol would leak information that may compromise the identity of its users. In this paper, we first present three attacks targeting BitTorrent users on top of Tor that reveal their real IP addresses. In a second step, we analyze the Tor usage by BitTorrent users and compare it to its usage outside of Tor. Finally, we depict the risks induced by this de-anonymization and show that users' privacy violation goes beyond BitTorrent traffic and contaminates other protocols such as HTTP.

  3. Generating Explanations for Biomedical Queries

    OpenAIRE

    Erdem, Esra; Oztok, Umut

    2013-01-01

    We introduce novel mathematical models and algorithms to generate (shortest or k different) explanations for biomedical queries, using answer set programming. We implement these algorithms and integrate them in BIOQUERY-ASP. We illustrate the usefulness of these methods with some complex biomedical queries related to drug discovery, over the biomedical knowledge resources PHARMGKB, DRUGBANK, BIOGRID, CTD, SIDER, DISEASE ONTOLOGY and ORPHADATA. To appear in Theory and Practice of Logic Program...

  4. Mobile Anonymous Trust Based Routing Using Ant Colony Optimization

    Directory of Open Access Journals (Sweden)

    R. Kalpana

    2012-01-01

    Full Text Available Problem statement: Ad hoc networks are susceptible to malicious attacks through denial of services, traffic analysis and spoofing. The security of the ad hoc routing protocol depends upon encryption, authentication, anonymity and trust factors. End-to-end security of data is provided by encryption and authentication, topology information of the nodes can be obtained by studying traffic and routing data. This security problem of ad hoc network is addressed by the use of anonymity mechanisms and trust levels. Identification information like traffic flow, network topology, paths from malicious attackers is hidden in anonymous networks. Similarly, trust plays a very important role in the intermediate node selection in ad hoc networks. Trust is essential as selfish and malicious nodes not only pose a security issue but also decreases the Quality of Service. Approach: In this study, a routing to address anonymous routing with a trust which improves the overall security of the ad hoc network was proposed. A new approach for an on demand ad-hoc routing algorithm, which was based on swarm intelligence. Ant colony algorithms were a subset of swarm intelligence and considered the ability of simple ants to solve complex problems by cooperation. The interesting point was, that the ants do not need any direct communication for the solution process, instead they communicate by stigmergy. The notion of stigmergy means the indirect communication of individuals through modifying their environment. Several algorithms which were based on ant colony problems were introduced in recent years to solve different problems, e.g., optimization problems. Results and Conclusion: It is observed that the overall security in the network improves when the trust factor is considered. It is seen that non performing nodes are not considered due to the proposed ACO technique.

  5. P2P Simulator for Queries Routing Using Data Mining

    Directory of Open Access Journals (Sweden)

    Anis ISMAIL

    2011-09-01

    Full Text Available Data mining is used to extract hidden information from large databases. In Peer-to-Peer context, achallenging problem is how to find the appropriate Peer to deal with a given query without overlyconsuming bandwidth. Different methods proposed routing strategies of queries taking into account theP2P network at hand. An unstructured P2P system based on an organization of Peers around Super-Peersthat are connected to Super-Super-Peer according to their semantic domains is considered. This paperintegrates Decision Trees in P2P architectures for predicting Query-Suitable Super-Peers representing acommunity of Peers, where one among them is able to answer the given query. In fact, by analyzing thequeries’ log file, a predictive model that avoids flooding queries in the P2P networks constructed bypredicting the appropriate Super-Peer, and hence the Peer to answer the query. The proposed architectureis based on a Decision Tree (Base-Knowledge - BK. The efficiency of these architectures is discussedconsidering architecture without knowledge (Baseline using only the flooding queries method to answerqueries. The advantage of this knowledge based model is the robustness in Queries routing mechanism andscalability in P2P Network.

  6. 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.

  7. 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...

  8. Evaluation of Query Generators for Entity Search Engines

    CERN Document Server

    Endrullis, Stefan; Rahm, Erhard

    2010-01-01

    Dynamic web applications such as mashups need efficient access to web data that is only accessible via entity search engines (e.g. product or publication search engines). However, most current mashup systems and applications only support simple keyword searches for retrieving data from search engines. We propose the use of more powerful search strategies building on so-called query generators. For a given set of entities query generators are able to automatically determine a set of search queries to retrieve these entities from an entity search engine. We demonstrate the usefulness of query generators for on-demand web data integration and evaluate the effectiveness and efficiency of query generators for a challenging real-world integration scenario.

  9. Algebra-Based Optimization of XML-Extended OLAP Queries

    DEFF Research Database (Denmark)

    Yin, Xuepeng; Pedersen, Torben Bach

    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......-based and cost-based query optimization and implementation are also proposed, as well as the execution techniques. Finally, experiments with the prototypical query engine w.r.t. federation performance, optimization effectiveness, and feasibility suggest that our approach, unlike the physical integration......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...

  10. Dynamic Query Optimization Approach for Semantic Database Grid

    Institute of Scientific and Technical Information of China (English)

    Xiao-Qing Zheng; Hua-Jun Chen; Zhao-Hui Wu; Yu-Xin Mao

    2006-01-01

    Fundamentally, semantic grid database is about bringing globally distributed databases together in order to coordinate resource sharing and problem solving in which information is given well-defined meaning, and DartGrid Ⅱ is the implemented database gird system whose goal is to provide a semantic solution for integrating database resources on the Web.Although many algorithms have been proposed for optimizing query-processing in order to minimize costs and/or response time, associated with obtaining the answer to query in a distributed database system, database grid query optimization problem is fundamentally different from traditional distributed query optimization. These differences are shown to be the consequences of autonomy and heterogeneity of database nodes in database grid. Therefore, more challenges have arisen for query optimization in database grid than traditional distributed database. Following this observation, the design of a query optimizer in DartGrid Ⅱ is presented, and a heuristic, dynamic and parallel query optimization approach to processing query in database grid is proposed. A set of semantic tools supporting relational database integration and semantic-based information browsing has also been implemented to realize the above vision.

  11. [E-research: problems with anonymity and consent].

    Science.gov (United States)

    Woolderink, Marla; van Asselt, Antoinette D I; van Schayck, Constant P; van Wijmen, Frans C B

    2013-01-01

    The Medical Research Involving Human Subjects Act (WMO) requires that participants in medical-scientific studies provide written consent. This requirement makes e-research (online research) unnecessarily difficult and sometimes impossible. Much of e-research involves online interventions that focus on sensitive issues such as sexual dysfunction, addiction and child abuse, for which anonymity is an important condition. WMO procedures, however, strictly interpret the word "written" as "on paper", and participants are not permitted to give consent by email, for example. A second requirement, which mainly makes studies among minors between the ages of 12 and 18 more difficult, is that both parents or the guardian must provide written consent. This undermines anonymity to such an extent that virtually no subjects remain. Participants in medical-scientific studies must always be identifiable to the investigator. But, apart from this, he/she should be possible to guarantee anonymity within the regulatory framework. There is good reason to adapt legal regulations to today's needs. PMID:24345359

  12. 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.

  13. 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. PMID:25494509

  14. Anonymous and Non-Repudiation E-Payment Protocol

    Directory of Open Access Journals (Sweden)

    Sattar J. Aboud

    2007-01-01

    Full Text Available There are many proposals offer anonymous and non-repudiation e-payment protocols. But they have the drawbacks that the anonymity can be misused by fraudulent to perform a perfect crimes. Currently, the hot research concentrates on the accepting of e-payment protocols where the anonymity of the coins is cancelable via a trusted authority in the case of criminal entities. In the article we suggest an efficient protocol for e-payment scheme that offers a good level of security with appreciate to its efficiency. The proposed protocol prevents the blind office and the bank from impersonate an entity, so that the entity could not repudiate it when the entity misused a coin. Another benefit is that it is constructed from efficient cryptography schemes so that its security can simply be analyzed. The strength of this scheme is in its easiness. So, we claim that the suggested protocol is more efficient than the existing schemes, since it allows to both a blind office and a bank to impersonate an entity to find and to spend a coin without to be noticed. It might cause a repudiation difficulty where the entity can repudiate his bad activities by proposing that both the bank and the blind office acted inaccurately. Other relevant issues related to the new protocol will be discussed in the section of the security of the scheme.

  15. Utility-guided Clustering-based Transaction Data Anonymization

    Directory of Open Access Journals (Sweden)

    Aris Gkoulalas-Divanis

    2012-04-01

    Full Text Available Transaction data about individuals are increasingly collected to support a plethora of applications, spanning from marketing to biomedical studies. Publishing these data is required by many organizations, but may result in privacy breaches, if an attacker exploits potentially identifying information to link individuals to their records in the published data. Algorithms that prevent this threat by transforming transaction data prior to their release have been proposed recently, but they may incur significant utility loss due to their inability to: (i accommodate a range of different privacy requirements that data owners often have, and (ii guarantee that the produced data will satisfy data owners’ utility requirements. To address this issue, we propose a novel clustering-based framework to anonymizing transaction data, which provides the basis for designing algorithms that better preserve data utility. Based on this framework, we develop two anonymization algorithms which explore a larger solution space than existing methods and can satisfy a wide range of privacy requirements. Additionally, the second algorithm allows the specification and enforcement of utility requirements, thereby ensuring that the anonymized data remain useful in intended tasks. Experiments with both benchmark and real medical datasets verify that our algorithms significantly outperform the current state-of-the-art algorithms in terms of data utility, while being comparable in terms of efficiency.

  16. An Analysis of Anonymity in the Bitcoin System

    CERN Document Server

    Reid, Fergal

    2011-01-01

    Anonymity in Bitcoin, a peer-to-peer electronic currency system, is a complicated issue. Within the system, users are identified by public-keys only. An attacker wishing to de-anonymize its users will attempt to construct the oneto- many mapping between users and public-keys and associate information external to the system with the users. Bitcoin frustrates this attack by storing the mapping of a user to his or her public-keys on that user's node only and by allowing each user to generate as many public-keys as required. In this paper we consider the topological structure of two networks derived from Bitcoin's public transaction history. We show that the two networks have a non-trivial topological structure, provide complementary views of the Bitcoin system and have implications for anonymity. We combine these structures with external information and techniques such as context discovery and flow analysis to investigate an alleged theft of Bitcoins, which, at the time of the theft, had a market value of approx...

  17. Deep Web信息资源的查询接口集成研究%Query Interfaces Integrating on Deep Web

    Institute of Scientific and Technical Information of China (English)

    林爱群; 习万球

    2011-01-01

    The Hidden Web databases contain much more searchable information than the Surface Web databases. If the query interfaces on the Deep Web are integrated, the recall and precision of web information retrieval will be highly improved. This paper discusses the clustering analysis for query schema integration problem. The query' interface schema integration method costs less, compared with the Deep Web data source integration.%Deep Web信息是隐藏在Web服务器中可搜索的数据库信息资源,其信息量远比表面web信息量大。将Deep Web信息查询的接口模式集成为统一的查询接口,将极大地提高web信息检索的查全率和查准率。讨论了查询模式集成问题的聚类分析方法,相对于直接对Deep Web数据源的进行集成,对查询模式加以集成的思路成本更低。

  18. 基于Web资源二次查询的信息检索策略研究%RESEARCH ON INFORMATION RETRIEVAL STRATEGY BASED ON SECONDARY WEB RESOURCE QUERY

    Institute of Scientific and Technical Information of China (English)

    宋宝贵; 田宝彩

    2013-01-01

    日常生活中,上网重复查询相关资源等情况十分普遍,但由于网络信息一直处于变化之中,Web资源二次查询与一般一次查询结果可能存在差异.主要通过实验方法针对Web资源二次查询检索行为特性进行分析与研究.研究结果显示,相对比于信息一次查询行为,在Web资源二次查询过程中所使用的检索方式、检索策略更为多元化、所采用的检索优化方法更丰富.为搜索引擎技术的发展进行了信息检索角度的有益探讨.%It is very common in daily life to access the internet for querying the related resources repeatedly. However, usually the result of the secondary query on Web resources may differ to the one from the first query due to constant variation of networks information. In this paper, we analyse and study mainly through the means of experiments the behaviour characteristics of secondary Web resource query and retrieval. Study result shows that, compared with the first information query behaviour, the retrieval means and strategies used in secondary Web resources querying process are more diversified, the retrieval optimisation approach used has more choices. This article made a useful discussion on the development of search engine technology in terms of information retrieval perspective.

  19. UMLS-Query: a perl module for querying the UMLS.

    Science.gov (United States)

    Shah, Nigam H; Shah, Nigam; Muse, Mark A; Musen, Mark

    2008-01-01

    The Metathesaurus from the Unified Medical Language System (UMLS) is a widely used ontology resource, which is mostly used in a relational database form for terminology research, mapping and information indexing. A significant section of UMLS users use a MySQL installation of the metathesaurus and Perl programming language as their access mechanism. We describe UMLS-Query, a Perl module that provides functions for retrieving concept identifiers, mapping text-phrases to Metathesaurus concepts and graph traversal in the Metathesaurus stored in a MySQL database. UMLS-Query can be used to build applications for semi-automated sample annotation, terminology based browsers for tissue sample databases and for terminology research. We describe the results of such uses of UMLS-Query and present the module for others to use. PMID:18998805

  20. 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.