Die zweite Phase der Feldbusentwicklung

The past decade may be regarded as the phase of the fundamental developments in fieldbus systems that were based on the OSI model. Today we are entering a second stage. It is the objective of this issue to present the current state and where the further developments will lead to. This introductory article is intended to give an overview on the subject.     

Auswirkungen von Blitzschlägen auf 20-kV-Energiekabel

Recently appeared defects on high voltage cables have required an urgent evaluation of the impact of lightning strikes necessary. In some cases overvoltages between the copper wire screen of the cable and earth may appear which cause damages of the cablesheath. Field measurements with a classification of the voltage impulses at the copper wire screen have been made to evaluate the number of events. Additionally a numerical model was developed to study the effects of atmospheric discharges on underground cables with emphasis to the influence on the cablesheath. This numeric method was also applied to estimate the effectiveness of different protection arrangements. This contribution presents evaluation methods for overvoltages of cables and a model used firstly for calculating the stress caused by differential voltages and secondly to determinate the influence of protection measures.     

Comparative characterization of endurance properties of ischemic myocardium in cyclic and quasistatic mechanical loads

The mechanical properties of totally ischemic hearts of inbred albino rats were studied. The ischemic myocardium was found to be more sensitive to cyclic loads. Energy deficient contracture of cardiomyocytes is a factor which increases the resistance of the myocardium to mechanical effects.     

Hydrogen Permeability of Borosilicate Glasses

Borosilicate glass-forming compositions R₂O – B₂O₃ – SiO₂ – R_aO_b (R — Li, Na, K; R_a — Zn, PbO) are investigated. A correlation-regression analysis of the criteria (the silicate modulus, the oxygen number, the structure cohesion factor, the relative molar volumes of the components) affecting the hydrogen permeability of glasses is carried out. The tendency for permeability variations depending on the component composition and the above specified criteria is identified.     

38. Generalversammlung von CENELEC

Ohne Zusammenfassung     

Essential phospholipids in the treatment of chronic pyelonephritis]

Through TCD test, observation on the blood flow dynamics change before and after treatment with 31 cases of the child cerebral atrophy was made. It is found that scalp therapy is able to speed up the blood flow of part artery, especially increase the even blood flow speed of MCA, ACA obviously (P < 0.05), which preliminary shows the mechanism of scalp therapy for child cerebral atrophy mean while. It is found that scalp therapy also has the function to restrain epilepsy.     

Qualitativ-quantitative Simulation, ein Instrument zur Analyse nichtlinearer Regelkreise

Qualitative-quantitative simulation is one of the most productive and promising research areas in Artificial Intelligence to emerge in recent years. This method provides an elegant way for an exhaustive analysis of uncertain dynamic systems. The application of the qualitative-quantitative simulation is shown in this paper. The important question about the stability of a quanlitatively described dynamical system is solved by a novel analytic method.