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Subtyping by constraints in object-oriented databases [chapter]

Wolfgang Kowarschick, Gerhard Köstler, Werner Kießling
1996 Lecture Notes in Computer Science  
For many object-oriented database applications taxonomies with a setinclusion semantics among the type extents are essential. In practical cases, however, common object-oriented modeling techniques often do not result in taxonomies as they ignore application specific constraints. We will elaborate that especially in domains like CAD or similar engineering environments integrity constraints on type attributes have a deep impact on the resulting hierarchy. We argue that subtyping by constraints
more » ... y be superior to other object-oriented alternatives like subtyping for generalization or nearly-flat hierarchies. Subtyping by constraints achieves a logical set-inclusion hierarchy, and in addition enables a larger amount of semantically correct substitutability. This can even be improved by a novel framework of automatic method adaptation for enhanced substitutability. Moreover, a potential storage penalty caused by making constraints explicit can be avoided completely by applying a new storage optimization technique based on functional integrity constraints. Our results are illustrated by practical examples drawn from the OCAD project. ¤
doi:10.1007/3-540-60954-7_57 fatcat:p6y7j26dozav3l25rban4bv5ii

Preference SQL — Design, Implementation, Experiences [chapter]

Werner Kießling, Gerhard Köstler
2002 VLDB '02: Proceedings of the 28th International Conference on Very Large Databases  
Current search engines can hardly cope adequately with complex preferences. The biggest problem of search engines directly implemented with standard SQL is that SQL does not directly understand the notion of preferences. Preference SQL extends standard SQL by a preference model based on strict partial orders, where preference queries behave like soft selection constraints. A variety of built-in base preference types and the powerful Pareto accumulation operator to construct complex preferences,
more » ... combined with the adherence to declarative SQL programming style, guarantees great programming productivity. The current Preference SQL optimizer does an efficient re-writing into standard SQL, including a high-level implementation of the skyline operator for Pareto-optimal sets. This pre-processor approach enables a seamless application integration, making Preference SQL available on a broad variety of SQL platforms including IBM DB2, Oracle, Microsoft SQL Server and Sybase. The benefits of Preference SQL technology comprise cooperative query answering and smart customer advice, leading to a higher e-customer satisfaction and shorter development times of personalized search engines for the e-service provider. We report experiences with practical applications ranging from m-commerce and comparison shopping to a large-scale performance test with real data. Several search engines of commercial B2C portals are powered by Preference SQL.
doi:10.1016/b978-155860869-6/50098-6 dblp:conf/vldb/KiesslingK02 fatcat:qyo26miekbhh3jfxxbpntvawbu

Client-Server Optimization for Multimedia Document Exchange

Gerhard Köstler, Wolfgang Kowarschick, Werner Kießling
1997 Database Systems for Advanced Applications '97  
The success of the World Wide Web is boosting the development of multimedia database systems and their integration into the internet. For the documents stored and exchanged in the Web there are many multimedia data formats di ering in aspects such as resolution, sampling rate, and compression. Furthermore there is a large variety of Web browsers, the data formats they support, and their network access. Thus storage servers have to store and proxy servers have to transfer many di erent formats.
more » ... owever, the data formats are not independent from each other but interrelated by conversion tools. There i s a l a r ge number of alternatives for storage and proxy servers to store some formats or to transfer them via the network and to compute the remaining ones by applying conversion tools. To determine an optimal choice is a nontrivial optimization problem and is subject to changes of the parameters such as query pro le, available disk storage, and network bandwidth. We examine the outlined optimization problem in the context of objectoriented databases and illustrate our approach by a practical real-world application.
doi:10.1142/9789812819536_0015 fatcat:ysnqsur7wfgmpi4lim3vgcd2di

Oscillating streaming potential measurement system for macroscopic surfaces

Martin Reischl, Stefan Köstler, Gerhard Kellner, Karin Stana-Kleinschek, Volker Ribitsch
2008 Review of Scientific Instruments  
A method and instrumentation is described capable of streaming potential measurements of various macroscopic surfaces. It differs from other approaches due to the creation of an oscillatory flow of electrolyte solutions through or alongside the sample. This technique offers a wide range of applied flow frequency and amplitude resulting in a fast and highly accurate measurement. This enables the streaming potential detection at rather high ionic strength and in a short time regime, which allows
more » ... he monitoring of adsorption processes. Streaming potential and applied pressure are measured simultaneously, together with the specific conductivity of the bulk solution, pH value, and temperature. Combining these data, the zeta potential ͑͒ for many different material types ͑fibers, films, foils, granules, and particles͒ can be calculated. The apparatus comprises reliable and robust measurements, simple handling, a high degree of automation, and advanced software control. With this setup, automated pH and concentration dependent -potential measurements are possible for a variety of analytes and adsorbing species ͑e.g., ionic strength, surfactants, polyelectrolytes, and proteins͒; time-resolved measurements are facilitated down to the seconds time scale. The device allows the necessary sample preparation and equilibration outside the instrument using exchangeable sample holders. This offers the opportunity of high sample throughput.
doi:10.1063/1.3020699 pmid:19045898 fatcat:2yzu2yqylrfezcvvxtyjmflxke

Performance engineering for the Lattice Boltzmann method on GPGPUs: Architectural requirements and performance results [article]

Johannes Habich and Christian Feichtinger and Harald Köstler and Georg Hager and Gerhard Wellein
2011 arXiv   pre-print
GPUs offer several times the floating point performance and memory bandwidth of current standard two socket CPU servers, e.g. NVIDIA C2070 vs. Intel Xeon Westmere X5650. The lattice Boltzmann method has been established as a flow solver in recent years and was one of the first flow solvers to be successfully ported and that performs well on GPUs. We demonstrate advanced optimization strategies for a D3Q19 lattice Boltzmann based incompressible flow solver for GPGPUs and CPUs based on NVIDIA
more » ... and OpenCL. Since the implemented algorithm is limited by memory bandwidth, we concentrate on improving memory access. Basic data layout issues for optimal data access are explained and discussed. Furthermore, the algorithmic steps are rearranged to improve scattered access of the GPU memory. The importance of occupancy is discussed as well as optimization strategies to improve overall concurrency. We arrive at a well-optimized GPU kernel, which is integrated into a larger framework that can handle single phase fluid flow simulations as well as particle-laden flows. Our 3D LBM GPU implementation reaches up to 650 MLUPS in single precision and 290 MLUPS in double precision on an NVIDIA Tesla C2070.
arXiv:1112.0850v1 fatcat:e2uvx3rhfjbvleyucxdzevmnoq

Taxonomic and uncertain integrity constraints in object-oriented databases---the TOP approach

Thomas Lukasiewicz, Werner Kießling, Gerhard Köstler, Ulrich Güntzer
1995 Proceedings of the fourth international conference on Information and knowledge management - CIKM '95  
Werner Kiet31ing, Thomas Lukasiewicz, Gerhard Kostler, and Ulrich Guntzer. The TOP database model -taxonomy, object-orientation and prob- ability.  ... 
doi:10.1145/221270.221580 dblp:conf/cikm/LukasiewiczKKG95 fatcat:mrv3avlfabhrpdi7o3sxqo6j3a

A flexible Patch-based lattice Boltzmann parallelization approach for heterogeneous GPU–CPU clusters

Christian Feichtinger, Johannes Habich, Harald Köstler, Georg Hager, Ulrich Rüde, Gerhard Wellein
2011 Parallel Computing  
Sustaining a large fraction of single GPU performance in parallel computations is considered to be the major problem of GPU-based clusters. In this article, this topic is addressed in the context of a lattice Boltzmann flow solver that is integrated in the WaLBerla software framework. We propose a multi-GPU implementation using a block-structured MPI parallelization, suitable for load balancing and heterogeneous computations on CPUs and GPUs. The overhead required for multi-GPU simulations is
more » ... scussed in detail and it is demonstrated that the kernel performance can be sustained to a large extent. With our GPU implementation, we achieve nearly perfect weak scalability on InfiniBand clusters. However, in strong scaling scenarios multi-GPUs make less efficient use of the hardware than IBM BG/P and x86 clusters. Hence, a cost analysis must determine the best course of action for a particular simulation task. Additionally, weak scaling results of heterogeneous simulations conducted on CPUs and GPUs simultaneously are presented using clusters equipped with varying node configurations.
doi:10.1016/j.parco.2011.03.005 fatcat:c6kcqpvkgbdvvjlho6qqldch3e

Whole Body Hyperthermia by Extracorporeal Circulation in Spontaneously Breathing Sarcoma Patients: Hemodynamics and Oxygen Metabolism

Gottfried J. Locker, Eva-Maria Fuchs, Nina Worel, Andja Bojic, Gerhard Heinrich, Thomas Brodowicz, Martin Clodi, Georg-Christian Funk, Paul Knöbl, Christoph C. Zielinski, Wolfgang J. Köstler
2011 International Journal of Artificial Organs  
Purpose: This phase I study was performed to evaluate the feasibility and toxicity of a new method of extracorporeal perfusion-induced whole body hyperthermia (WBHT) in patients with advanced sarcoma avoiding the need of intubation and general anesthesia. Methods: One double-lumen femoral venous access was inserted by Seldinger´s technique to obtain WBHT (41.8°C for 120 minutes) via an extracorporeal circuit. No concomitant chemotherapy was applied. Up to 4 treatments of WBHT were performed
more » ... r moderate sedation in 6 spontaneously breathing patients. Invasive hemodynamic monitoring was performed by use of a pulmonary artery catheter. Results: After their first WBHT session, 2 patients were excluded from further treatment due to transient liver toxicity or catheter related complication, so a total of 12 cycles remained for analyses. In all patients, conscious sedation resulted in sufficient spontaneous respiration without the need of mandatory ventilation. Median time to reach the target temperature was 84 minutes (range 60-142). Hemodynamic changes revealed the expected hyperdynamic state: Heart rate, cardiac index and stroke volume index significantly increased (p < 0.05), whereas blood pressure and systemic and pulmonary vascular resistance index significantly decreased (p < 0.05). A net fluid balance of 5822 + 1766 ml as well as norepinephrine (mean; 0.062 μg.kg -1 .min -1 ) were necessary to maintain the mean arterial blood pressure > 60 mm Hg. Conclusion: Our data demonstrate the feasibility of this method of extracorporeal WBHT without mandatory ventilation. Hemodynamic side effects in spontaneously breathing patients during perfusion-induced WBHT seem less severe than those observed in radiant heat WBHT.
doi:10.5301/ijao.5000009 pmid:22183522 fatcat:xfperxjk3ver7fxdbmp2cujbvm

Validation of T-Track® CMV to assess the functionality of cytomegalovirus-reactive cell-mediated immunity in hemodialysis patients

Bernhard Banas, Carsten A. Böger, Gerhard Lückhoff, Bernd Krüger, Sascha Barabas, Julia Batzilla, Mathias Schemmerer, Josef Köstler, Hanna Bendfeldt, Anne Rascle, Ralf Wagner, Ludwig Deml (+2 others)
2017 BMC Immunology  
Uncontrolled cytomegalovirus (CMV) replication in immunocompromised solid-organ transplant recipients is a clinically relevant issue and an indication of impaired CMV-specific cell-mediated immunity (CMI). Primary aim of this study was to assess the suitability of the immune monitoring tool T-Track® CMV to determine CMV-reactive CMI in a cohort of hemodialysis patients representative of patients eligible for renal transplantation. Positive and negative agreement of T-Track® CMV with CMV
more » ... was examined in 124 hemodialysis patients, of whom 67 (54%) revealed a positive CMV serostatus. Secondary aim of the study was to evaluate T-Track® CMV performance against two unrelated CMV-specific CMI monitoring assays, QuantiFERON®-CMV and a cocktail of six class I iTAg™ MHC Tetramers. Results: Positive T-Track® CMV results were obtained in 90% (60/67) of CMV-seropositive hemodialysis patients. In comparison, 73% (45/62) and 77% (40/52) positive agreement with CMV serology was achieved using QuantiFERON®-CMV and iTAg™ MHC Tetramer. Positive T-Track® CMV responses in CMV-seropositive patients were dominated by pp65-reactive cells (58/67 [87%]), while IE-1-responsive cells contributed to an improved (87% to 90%) positive agreement of T-Track® CMV with CMV serology. Interestingly, T-Track® CMV, QuantiFERON®-CMV and iTAg™ MHC Tetramers showed 79% (45/57), 87% (48/55) and 93% (42/45) negative agreement with serology, respectively, and a strong inter-assay variability. Notably, T-Track® CMV was able to detect IE-1-reactive cells in blood samples of patients with a negative CMV serology, suggesting either a previous exposure to CMV that yielded a cellular but no humoral immune response, or TCR cross-reactivity with foreign antigens, both suggesting a possible protective immunity against CMV in these patients. Conclusion : T-Track® CMV is a highly sensitive assay, enabling the functional assessment of CMV-responsive cells in hemodialysis patients prior to renal transplantation. T-Track® CMV thus represents a valuable immune monitoring tool to identify candidate transplant recipients potentially at increased risk for CMV-related clinical complications.
doi:10.1186/s12865-017-0194-z pmid:28270092 pmcid:PMC5339958 fatcat:zmomrgclxjhmpez33ezflazwza

Inhalt

1942 Mitteilungen des Instituts für Österreichische Geschichtsforschung  
Köstler) 271 Schneider Friedrich, Deutsches Dante-Jahrbuch (Helmut Kämpf) . . . 272 Schindler Gerhard, Das Breslauer Domkapitel von 1341-1417 und Zimmermann Gerhard, Das Breslauer Domkapitel im Zeitalter  ...  Zatschek) . . 521 W a i s Gerhard Julius, Die Alamannen in ihrer Auseinandersetzung mit der römischen Welt.  ... 
doi:10.7767/miog.1942.54.34.v fatcat:pdvvrtyzojchffpcddovytq6nm

Bemerkungen zur gemeinwirtschaftlichen, einschließlich genossenschaftlichen Einzelwirtschaftslehre und Sozialpolitikwissenschaft im System der Wissenschaft von der Gesellschaftsgestaltungspolitik

Frank Schulz-Nieswandt
2011 ZögU. Zeitschrift für öffentliche und gemeinwirtschaftliche Unternehmen. Journal for Public and Nonprofit Services  
2011; Köstler/Schulz-Nieswandt 2010).  ...  Bedauerlich ist die fehlende Internationalisierung der Kölner Sozialpolitik-und Gemeinwirtschaftslehre dehalb, weil herausgearbeitet werden konnte, dass bei Gerhard Weisser sogar zentrale Ideen von John  ... 
doi:10.5771/0344-9777-2011-1-101 fatcat:h4h47m5agrf6fgungxu4itj3yq

Table of Contents

2020 2020 International Symposium on Reliable Distributed Systems (SRDS)  
Reiser (University of Passau), and Johannes Köstler (University of Passau) Session 6: Security and Privacy I On the Detection of Shilling Attacks in Federated Collaborative Filtering 185 Yangfan  ...  InterDigital, University de Rennes), Christoph Neumann (InterDigital), and François Taïani (University de Rennes) Self-Optimising Application-Agnostic Multithreading for Replicated State Machines 165 Gerhard  ... 
doi:10.1109/srds51746.2020.00004 fatcat:3fvwuol6bvbabcipcpe2zmnruu

Vorwort

G. Neweklowsky
2007 Wiener Slavistisches Jahrbuch Neue Folge  
Klagenfurt, im Mai 2007 Gerhard Neweklowsky .  ...  (Pohl, Holzer), Protestantismus (Katič i ć , Neweklowsky), Sprach-und Wissenschaftsgeschichte (Rajšp, Bonazza, Sturm-Schnabl, Hüttl-Hubert), Dialektologie (Smole), Übersetzungswissenschaft (Prun č , Köstler  ... 
doi:10.1553/wsj53s5 fatcat:2kzgw3g7lzambeqkkq7bnmfhoq

M.A.U.S.S. spielen! Die Gabe im multi-disziplinären Blick – Über den zentralen anthropologischen Baustein der Reziprozität und Mutualität als kulturgrammatische Prinzipien der genossenschaftlichen Gestalt

Frank Schulz-Nieswandt
2014 ZögU. Zeitschrift für öffentliche und gemeinwirtschaftliche Unternehmen. Journal for Public and Nonprofit Services  
Klein 2010; Stephan 2010; an die älteren 17 Beiträge von Helmuth Berking, Gerhard Schmied und von Johanna Krafft-Krivanic erinnernd) oder des Stiftens (mit einer Reihe gerade jüngerer Fachbeiträge: vgl  ...  Köstler 2013. Wir haben in Köln die Reziprozitätsforschung in recht unterschiedlichen Themenfeldern an Sozialgebilden der (gegenseitigen) Hilfe angesiedelt. Vgl.  ... 
doi:10.5771/0344-9777-2014-1-2-112 fatcat:74whacmjuvf63ldnzyltgcmfzq

Kanonistische Chronik

A. W.
1912 Zeitschrift der Savigny-Stiftung für Rechtsgeschichte Kanonistische Abteilung  
Gerhard Löschcke im Alter von 32 Jahren. Am 1. August 1912 starb in Halle an der Saale der ordentliche Professor der praktischen Theologie D. Paul Drews.  ...  Köstler wurde zur Supplierung der Lehrkanzel für Kirchenrecht während des Wintersemesters 1912/13 nach Wien berufen und zum außerordentlichen Professor des Kirchenrechts an der Universität Czernowitz ernannt  ... 
doi:10.7767/zrgka.1912.2.1.493 fatcat:r4pclrp6x5ayxb5uwzf4myldby
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