Fighting Computer Crime with Software Risk Analysis

Executive management must have a sound basis for deciding how to control and protect business systems. The potential cost/risk of a system exposure must be quantified before an intelligent cost/benefit decision can be made. Risk analysis attempts to address this need by analyzing exposures in a systematic way. The authors describe one organization's application of risk analysis techniques to software systems.     

New calix[4]arenedimethacrylate derivatives for dental composites

Calix[4]arenes were double alkylated with various alkylhalogenides and the residual OH functions were subsequently dimethacrylated with methacryloyl chloride. The successful synthesis of polymerizable calixarenes was proved using ¹H NMR spectroscopy, matrix‐assisted laser desorption ionization time‐of‐flight mass spectrometry and differential scanning calorimetry. The polymerization behaviour was confirmed by copolymerization with methacrylic acid methyl ester. Furthermore, the flexural strength, the flexural modulus of elasticity, the exothermic course of the photo‐curing reaction and the polymerization shrinkage of experimental dental filling composites containing the modified calixarenes were evaluated. Copyright © 2012 Society of Chemical Industry     

Wälzlager in der Vakuumtechnik

Rolling Bearings For The Use In Vacuum The use of rolling bearings in vacuum is limited due to technical reasons regarding the standard lubricants. Nevertheless there are options to use those machine elements anyways. Therefore an alternative lubrication, e.g. Molybdenum Disulfide, will be applied successfully. as a result rolling bearings can be used in surroundings with high temperatures as well as in vacuum. The following describes how the assume the lifetime of rolling bearings and shows how to optimize the systems with respect to its lifetime and therewith to the costs of the element by using it within such extreme surroundings. The shown options then will be proved by experimental tests.     

Distributed synthesis for regular and contextfree specifications

We consider the distributed realizability problem for systems with regular and deterministic contextfree local specifications. We characterize exactly the architectures for which the realizability problem is decidable. This extends known results on local specifications in two directions. First, architectures with cycles are allowed instead of just acyclic ones and second, deterministic contextfree specifications are considered.     

Composite materials of melt-spun Mg90Ni10 and graphite: Microstructural changes during cyclic hydrogenation and the impact on gas and heat transport characteristics

It is of high technical importance to consider the loading and unloading dynamics of hydride-based hydrogen storage tanks, which are mainly influenced by the heat and gas transfer properties inside the reaction bed. In this regard, hydride-graphite composites offer improved heat transfer properties and higher volumetric storage capacities compared to commonly used powder beds.