Tài liệu Advances in Database Technology- P4 pdf

... is based upon ciphertext, while, in the second, the intermediate index is based upon plaintext and the final index is obtained by encrypting the intermediate index. Based upon characteristics ... xor-ing them) to obtain ciphertext. Decryption involves reversing the process: combining the key-stream with the ciphertext to obtain the original plaintext. Along with the initial encryption key,...

Ngày tải lên: 14/12/2013, 15:15

... following information is maintained about each group of records For each attribute we maintain the sum of corresponding values. The corresponding value is given by We denote the corresponding first- order ... Preserving Data Mining 195 data set is a good substitute for privacy preserving data mining algorithms. For each dimension pair let the corresponding entries in the covariance matrix f...

Ngày tải lên: 14/12/2013, 15:15

... and H. Garcia-Molina. The Demarcation Protocol: A Technique for Maintaining Linear Arithmetic Constraints in Distributed Database Systems. In EDBT, 1992. A. Cerpa and D. Estrin. ASCENT: Adaptive ... given later in this section. 5.2 Calculating the Gain of Each Node Our algorithm updates the width of the filter installed in each node by considering the potential gain of increasing th...

Ngày tải lên: 24/12/2013, 02:18

... could be obtained through mining or just from in- formation retrieval. Data mining is an important tool in making the web more intelligent. That is, data mining may be used to mine the data on ... with work on information systems engineering involving, for example, databases and web services. E. Bertino et al. (Eds.): EDBT 2004, LNCS 2992, pp. 3–16, 2004. © Springer-Verlag Berlin Heidelbe...

Ngày tải lên: 14/12/2013, 15:15

... watermark. Energy-Conserving Air Indexes for Nearest Neighbor Search 51 Fig. 1. Data and Index Organization Using the Interleaving Technique for broadcasting along with the data objects [8]. By first examining the index information ... sorted according to the x-dimension since the grid cell is flat. Given a query point shown in the figure, nine objects are broken into two lists, with one co...

Ngày tải lên: 14/12/2013, 15:15

... of specific core points. For instance, if the core-point B is vis- ited first during the DBSCAN run, the core-points A and C are not included in Scor. In the following, we introduce two local ... approaches in query processing for moving object trajectories. In VLDB, 2000. S. Prabhakar, Y. Xia, D. V. Kalashnikov, W. G. Aref, and S. E. Hambrusch. Query indexing and velocity constrained...

Ngày tải lên: 14/12/2013, 15:15

... relational databases into an XML format or to store the information in an XML object in a relational database, increasing the cost of e-business development. Moreover, specifying the mapping in the ... (such as preceding-sibling and following-sibling). Even more complex are the following and preceding axes. Our goal in normalizing the Xpath expression is to bring it to a form in wh...

Ngày tải lên: 14/12/2013, 15:16

... Matching. Most database systems allow matching text strings using pseudo- phonetic Soundex algorithm originally defined in [11], primarily for Latin-based scripts. In summary, while current databases ... environment. 5.3 Phonetic Indexing We now outline a phonetic indexing technique that may be used for accessing the near- equal phonemic strings, using a standard database index. We ex...

Ngày tải lên: 14/12/2013, 15:16

... designing the annotation specifications, considering the specifics of data integrity constraint checking, and ascertaining the impact on particular tools remain challenging (and interesting) tasks. focuses ... in the games and the information shown in Fig. 1 Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark. Computing and Handling Cardinal Direction Information...

Ngày tải lên: 14/12/2013, 15:16

... pruning steps using can be done to do more effective pruning, since the two sets are symmetric in this join problem. 4 Constructing NNH Using Good Pivots Pivot points are vital to NNH for obtaining ... between index nodes from corresponding trees in a priority queue and recursively (top-down) refining the search. In this case, using histograms, one could perform, in addition to the ty...

Ngày tải lên: 24/12/2013, 02:18