Enterprise networks: The re-engineering of complex software systems

Today technology design can no longer be understood as a design process on a green site. Design and implementation of new technology are always dependent on existing technology and the way it is used by people. In this respect Software-Engineering has also changed to the characteristics of normal technology design taking into account existing computer systems. Experiences show that the conditions and needs of such Software-Reengineering projects are highly complex and differ in their special characteristics ranging from aspects of quality of existing system documentation to organizational structures of the computer departments concerned. The Task-Artifact Cycle presented here gives a suitable reengineering approach emphasizing both analysis and design in Software-Reengineering.     

Using VNIR and SWIR field imaging spectroscopy for drought stress monitoring of beech seedlings

Drought stress is expected to become a recurrent problem for central European forests due to regional climate change. In order to study the effects on one of the most common tree species in Germany, the European beech (Fagus sylvatica), young potted beech trees were exposed to drought stress in a controlled experiment and their reaction was observed using visible/near-infrared (VNIR) and shortwave infrared (SWIR) field imaging spectroscopy cameras mounted on a platform. Equivalent water thickness (EWT) and leaf chlorophyll content (LCC) were measured and partial least squares (PLS) regression models were trained using these reference measurements and reflectance spectra of the trees. The models were applied to create maps of these properties with a spatial resolution in the millimetre range. These maps can be used to study the spatial distribution of EWT and LCC for single leaves or even for intra-leaf variability. Both properties can be estimated using only the VNIR sensor, but EWT estimation improves considerably by also incorporating SWIR data. LCC estimations with SWIR data alone do not work satisfactorily.     

Carnocin U149, a potential biopreservative produced by Carnobacterium piscicola: large scale purification and activity against various Gram-positive bacteria including Listeria sp.

This paper describes a simple purification method for the purification of carnocin U149, a potential biopreservative produced by Carnobacterium piscicola U149. The protocol was also applicable for the isolation of nisin Z, which is a biopreservative produced by Lactococcus lactis SIK-83. The protocol consists of only two purification steps, XAD chromatography and cation exhange chromatography. It is quick, easy, and can be used for large scale purification of these lantibiotics. The bactericidal activity of carnocin U149 against carnobacteria, lactococci and Listeria was compared with that of nisin Z. The carnobacteria showed similar sensitivity towards carnocin U149 and nisin. The nisin producing L. lactis strains were very sensitive towards carnocin U149, while the non-producing L. lactis strains were more sensitive to nisin. The Listeria strains were weakly sensitive to carnocin U149, lower concentrations of nisin were needed to inhibit growth.     

Recent Advances in TWX Mechanization

Equipment is presently being manufactured which permits the TWX subscriber to place his calls directly by dialing into the DDD telephone network. This equipment comprises electronic and electromechanical devices, combined in a simple package for installation at the subscriber's premises. The Data Set, with its associated controlling Subset, provides a number of operating features which make for convenience, speed, and ease of operation, and should assure reliable operation for a great many years.     

Influence of nonylphenol on the microbial community of lake sediments in microcosms

In this study the impact of nonylphenol, an estrogenic degradation product of alkylphenol polyethoxylates, on the microbial community structure in contaminated sediments of aquatic microcosms using in situ hybridization with fluorescently labeled oligonucleotides probes was investigated. A positive correlation between nonylphenol concentration and cell numbers of bacteria and microfungi as well as an increase in the numbers of active bacteria was found. However, the ratio between total microorganisms and active bacteria remained unchanged. A large fraction of the cells could be identified using group specific oligonucleotide probes. A slight change in the composition of the microbial community structure was observed, with Gram-positive bacteria with high DNA G + C-content becoming more abundant at higher concentrations of nonylphenol.     

Zur Prüfung von Schweißplattierungen mit austenitischen Bandelektroden der Art X2 CrNiNb 2413 auf Beständigkeit gegen interkristalline Korrosion

Testing of weld-claddings with austenitic band electrodes of the type X2CrNiNb24 13 for resistance against intercrystalline corrosion Two-phase, austenite- and ferrite-containing weld claddings of the 24 Cr-13 Ni-type may become susceptible to intercrystalline corrosion after heat-treatment in the 550°C temperature range due to a sensitization of the austenite. Thus, both austenite/austenite- and austenite/ferrite grain boundaries are attacked with the attack starting from the austenite phase in the latter case. Testing the resistance to intercrystalline corrosion in a sulphuric acid/copper sulphate media in the presence of copper turnings according to DIN 50914, the attack of grain boundaries ferrite/austenite becomes evident only if the specimens are bent after testing. Non-bent specimens do not show any indication of grain boundary attack by light-optical or even electron-microscopical metallographic examination. At non-bent specimens, the attack may become recognizable with considerably prolonged (several hundred hours) testing time. Referring to the investigations performed, the mechanism of intercrystalline corrosion of two-phase, ferritic-austenitic stainless steels and the influence of heat-treatment on susceptibility to intergranular attack are discussed.     

Generation of 224-nm radiation by stimulated Raman scattering of ArF excimer laser radiation in a mixture of H2 and D2

Raman shifting of tunable ArF excimer laser radiation in a mixture of H(2) and D(2) produces tunable radiation in the 224-nm region as a result of Stokes shifting the frequency of the fundamental radiation (193 nm) once in both H(2) and D(2). At a total pressure of 25 bars, a 19% H(2) in D(2) mixture is found to provide a maximum conversion efficiency (2.5%) to the 224-nm range. Both fundamental and 224-nm radiation were used to record laser-induced fluorescence excitation spectra of nitric oxide produced in an oxyacetylene flame. From the excitation spectra, we determined the tuning range of the 224-nm radiation to be 270 cm(-1) with a linewidth of 0.9 cm(-1), which is similar to the fundamental laser radiation. We derived the exact Raman shift of the generated radiation by comparing both excitation spectra which was found to be 7142.3(5) cm(-1).     

Fixed‐Bed Adsorption of Allura Red Dye on Chitosan/Polyurethane Foam

The potential of a chitosan/polyurethane foam (CTS/PU) fixed‐bed column for the removal of Allura Red dye (AR) from aqueous solutions was evaluated. Breakthrough curves were constructed under different conditions and optimized using response surface methodology (RSM). The empirical models Thomas, Yoon‐Nelson, and Bed Depth Service Time (BDST) were fitted to the experimental data. The dynamic models of Yoon‐Nelson and BDST accurately fitted the experimental data. As a result, CTS/PU can be successfully applied in a fixed‐bed adsorption operation to remove AR dye.