Wege zur Absicherung eines Intranets

Zusammenfassung Ziel dieses Artikels ist es, einen überblick über technische Sicherheitsl?sungen für Intranets zu geben. Ein Modell, das die Anforderungen an ein Sicherheitssystem in Form von abstrakten Diensten abbildet, dient dazu, verschiedene L?sungsalternativen zur Realisierung der unterschiedlichen Dienste auf Basis offener Standards oder generalisierter Produktklassen beurteilen zu k?nnen. Darauf aufbauend wird eine beispielhafte Referenzarchitektur für Unternehmen auf Basis einer X.509 Public-Key-Infrastruktur entworfen.      

Die Systemǵleichunǵen der Drehstrom-Asynchronmaschine beim zweipoliǵen Kurzschluß

Ohne Zusammenfassung     

Das BONITAS-System

Tool support for professional credit-rating is currently dominated by data-oriented approaches. This results in primarily focusing on hard facts in the financial institutions’ process of evaluating credit inquiries of their customers. Content objects and arguments which cannot algorithmically be mapped onto rigid data-tables (?soft facts”), however, with the potential of having a decisive impact on credit assessment, tend to be not sufficiently and appropriately placed into consideration. The BONITAS system overcomes this structural lack of information processing in traditional credit management systems in adding to the traditional approach innovative groupware-enabled capabilities. Compound documents in a messaging context are used to be integrative containers for all relevant information. These documents support both information gathering and evaluation of ?hard” data and ?soft” facts as well as semi-structured information gathering workflows allowing for a continuum of assessment-specific process options. The creation of valid and marketable business knowledge in credit management processes is basically team-driven. Thus, the essential features of groupware-based information management systems, i.e. their outstanding capabilities in communication, collaboration and coordination, represent critical baselines for improving the decision quality in credit-rating. An important goal of the BONITAS system is to aim at creating a constantly improved knowledge base on credit management workflows. This knowledge base is continuously being maintained in the operational progress of customer projects. It enables the financial institution to judge on the financial strength of upcoming clients in a holistic and anticipating evaluation process superior to traditional much more static assessments.     

Concentration effects of methylalumoxane, palladium and nickel pre-catalyst and monomer in the vinyl polymerization of norbornene

Summary The vinyl polymerization of norbornene with di-μ-chloro-bis-(6-methoxybicyclo-[2.2.1]hept-2-ene-5σ,2π)-palladium(II), Ni(acetylacetonate)₂ and Ni(2-ethylhexanoate)₂ in combination with methylalumoxane (MAO) was investigated by varying the molar MAO:metal-complex ratio, the norbornene:metal ratio and the metal concentration. The effects on the catalyst activity could be explained with a complexation equilibrium for the active homogeneous complex. Activity data in combination with polymer analyses suggest that at low, yet economical Al(MAO):metal ratios of 100 the fraction of active metal centers is less than 15%. The turnover frequency for the monomer insertion was found to reach 50 s⁻¹. Polydispersities around M_w/M_n= 2 indicate a coordination polymerization with chain transfer and a single-site character of the active centers. Received:27 February 2001/Revised version:11 November 2001/ Accepted: 20 November 2001