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Ohne Zusammenfassung  相似文献   
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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   
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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   
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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   
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Forum / Kolumne     
Hinter den Lehrbüchern die vorlesende Forscherpers?nlichkeit, hinter dem Prospekt der Rat des erfahrenen Fachverk?ufers.  相似文献   
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We present a structured procedure for order pick system (OPS) analysis and design that has been established on literature review and interviews with and presentations to OPS experts. In particular, we attempt to include the thinking processes that occur between OPS designers and owners. The design procedure and related issues are discussed in the order of input, selection, and evaluation stages.  相似文献   
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All boiling water reactor (BWR) degraded core experiments performed prior to CORA-33 were conducted under ‘wet’ core degradation conditions, in which water remains within the core and continuous steaming feeds metal-steam oxidation reactions on the in-core metallic surfaces. However, one dominant set of accident scenarios would occur with reduced metal oxidation under ‘dry’ core degradation conditions and, prior to CORA-33, this set had been neglected experimentally. The CORA-33 experiment was designed specifically to address this dominant set of BWR ‘dry’ core severe accident scenarios and to resolve partially phenomenological uncertainties concerning the behavior of relocating metallic melts that drain into the lower regions of a ‘dry’ BWR core (the ex-reactor experiments at Sandia National Laboratories will further address these uncertainties). CORA-33 was conducted on 1 October 1992, in the CORA test facility at Karlsruhe. A review of the CORA-33 data indicates that the objectives were achieved; i.e. core degradation occurred at a core heat-up rate (characterized by the absence of any temperature escalation caused by oxidation) and a test section axial temperature profile (at incipient structural melting) that are prototypic of full-core nuclear power plant simulations under ‘dry’ core conditions. Simulations of the CORA-33 test at Oak Ridge National Laboratory (ORNL) have required the modification of existing control blade-canister materials interaction models to include the eutectic melting of the stainless steel-zircaloy interaction products and the heat of mixing of stainless steel and zircaloy. The timing and location of canister failure and melt intrusion into the fuel assembly appear to be adequately simulated by the ORNL models. This paper will present the results of the post-test analyses carried out at ORNL based on the experimental data and the post-test examination of the test bundle at Karlsruhe. The implications of these results with respect to degraded core modelling and the associated safety issues are also discussed.  相似文献   
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