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1.
2.
Gunter Dueck 《Informatik-Spektrum》2008,31(4):353-357
Ohne Zusammenfassung 相似文献
3.
Dealing with discrepancies in data is still a big challenge in data integration systems. The problem occurs both during eliminating duplicates from semantic overlapping sources as well as during combining complementary data from different sources. Though using SQL operations like grouping and join seems to be a viable way, they fail if the attribute values of the potential duplicates or related tuples are not equal but only similar by certain criteria. As a solution to this problem, we present in this paper similarity-based variants of grouping and join operators. The extended grouping operator produces groups of similar tuples, the extended join combines tuples satisfying a given similarity condition. We describe the semantics of this operator, discuss efficient implementations for the edit distance similarity and present evaluation results. Finally, we give examples of application from the context of a data reconciliation project for looted art. 相似文献
4.
Prof. Dr. Gunter Dueck IBM
Distinguished Engineer DUECK@DE.IBM.COM 《Informatik-Spektrum》2004,27(2):186-191
Alpha Versionen sind Lehrbücher,
Gesetze, Produkthochglanzprospekte, Aktienneuemissionsanzeigen,
Regierungserklärungen. Dahinter ist das Reale. Hinter den
Lehrbüchern die vorlesende Forscherpersönlichkeit, hinter dem
Prospekt der Rat des erfahrenen Fachverkäufers. Alpha Versionen
meiden Urteile, Meinungen und Leidenschaftlichkeit. Diese
Kolumne ist kompromißlos beta. 相似文献
5.
This paper focuses on designing the optimal layout of measurements for parameter identification problems in geomechanics, which are usually based on in situ displacements. The existence, uniqueness, and stability of the solution from the parameter identification process are thoroughly discussed. Based on these understandings of the problem, two algorithms are proposed as a means of automatically generating the optimal measurements. The validity of these algorithms is first proved by some academic examples, then these algorithms are applied to the Munich subway tunnel project. Good results are observed there. 相似文献
6.
The testing and quality assurance of the Motif 1.0 graphical user-interface software are described. The testing goals, which fell into three general categories (code coverage, defect-density, and defect-arrival rate), and a deliverable formal test suite are examined. The three phases of the testing process-evaluation, test development, and regression testing-and the tools used in testing are discussed 相似文献
7.
Cell suspensions of Escherichia coli as a model for bacterial populations in wastewaters were treated with ozone as a disinfectant in a continuously operated pilot plant with a plug flow reactor. Suspensions with an initial number of CFU (colony forming units) of 108 mL?1 were ozonized with ozone concentrations up to 12 mg/L. Metabolic activities and membrane functions break down with increasing ozone concentrations. The fluorochromization using 3′,6′-diacetylfluorescein (FDA) proved to be a suitable method for the detection of an alteration in permeability of the cell membranes and an inactivation of metabolic activity. By fluorescence microscopic and photometric investigations it could be clearly demonstrated that, in the case of disinfection with ozone, inactivation of the cells includes first of all a damage of the cell membranes. In contrast to the determination of the number of CFU, fluorochromization allows the detection of alteration in metabolic activities. 相似文献
8.
R Albrecht TC Awes C Baktash P Beckmann F Berger R Bock G Claesson G Clewing L Dragon A Eklund RL Ferguson A Franz S Garpman R Glasow HA Gustafsson HH Gutbrod J Idh P Jacobs K Kampert BW Kolb P Kristiansson IY Lee H Loehner I Lund FE Obenshain A Oskarsson I Otterlund T Peitzmann S Persson F Plasil AM Poskanzer M Purschke H Ritter S Saini R Santo HR Schmidt T Siemiarczuk SP Sorensen E Stenlund ML Tincknell GR Young 《Canadian Metallurgical Quarterly》1991,44(6):2736-2752
9.
Chandrasekhar S. Lunardi L.M. Gnauck A.H. Ritter D. Hamm R.A. Panish M.B. Qua G.J. 《Electronics letters》1992,28(5):466-468
Metal organic molecular beam epitaxy (MOMBE) was successfully used for the first time to realise a high speed monolithic photoreceiver. Incorporating an InGaAs pin photodetector followed by a transimpedance preamplifier circuit implemented with InP/InGaAs heterojunction bipolar transistors (HBTs), the OEIC photoreceiver had a bandwidth of 6 GHz and a midband transimpedance of 350 Omega . In a system experiment performed at 10 Gbit/s, the receiver exhibited a sensitivity of -15.5 dBm for a bit error rate of 10/sup -9/ at a wavelength of 1.53 mu m. This is the first demonstration of operation of a long wavelength OEIC photoreceiver at this speed.<> 相似文献
10.
Gunter Dueck 《Informatik-Spektrum》2002,32(1):370-391
Hinter den Lehrbüchern die vorlesende Forscherpers?nlichkeit, hinter dem Prospekt der Rat des erfahrenen Fachverk?ufers. 相似文献