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This paper is devoted to the study of the symmetry of the Rabi pedestal of the clock transition in an optically pumped Cs beam frequency standard. The frequency of the microwave oscillator is locked on the center of the Rabi pedestal using a square wave frequency modulation. We observe a modulation of the center frequency as a function of the modulation depth. Experimental investigations on this unexpected effect are reported.
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In the last few years, several different interferons have been described, cloned, sequenced, expressed in heterologous systems and purified to homogeneity (Weissmann et al., 1982; Kingsman & Kingsman, 1983). In particular for human interferons there exists at least thirteen subtypes of IFN-α, one IFN-β and one IFN-γ. All these molecular species and some of their recombinant hybrids show a number of common biological properties but also distinctive antiviral (Weck et al., 1981; Kingsman & Kingsman, 1983) and other activities (Rehberg et al., 1982; Pestka et al., 1983b). Recombinant DNA technology has substantially contributed to the study of the mechanism of action of interferon and will probably continue to do so in the future by allowing a detailed analysis of the regulation and site-directed mutagenesis of IFN-induced proteins.
Abstract Bei unserer Suche nach neuen Virustatika haben wir 2.3(1H,4H)‐Chinoxalindion‐Derivate synthetisiert und auf ihre antivirale Aktivität gegen verschiedene Stämme des Virus Herpes Simplex Typ 1 und Typ 2, gegen Vaccinia Viren und gegen Vesicular Stomatitis Viren getestet. Keine der Verbindungen zeigte eine signifikante antivirale Aktivität im Vergleich mit 5‐Ethyl‐2′‐desoxyuridin (EtUdR).
In this paper a real-time control and optimization system for laser flame cutting of thick plates of mild steel is presented. The proposed system consists of two subsystems, namely a process monitoring and a control and optimization module. The process monitoring module evaluates the cut quality by measuring a set of sensing parameters, which are well-correlated with different quality characteristics of the cut surface. The applicability of different optical sensors (photodiodes and a NIRcamera) has been investigated. An overview of the most suitable set of sensing parameters is presented. The correlations between different quality deteriorations and the sensing parameters are mentioned as well as the reasons for these correlations. The real-time control and optimization module is implemented as an expert system with a dual functionality. On the one hand, it compares the sensing parameters with predefined thresholds and assigns one of the predefined quality classes to the instantaneous cut quality. On the other hand, it modifies the cutting parameters based on the predefined set of interpretable rules corresponding to the identified quality class. The obtained results prove the effectiveness of the chosen approach in terms of increased autonomy, productivity, and efficiency of the process, as well as elimination of the need for manual quality control and the possibility to automatically generate quality reports.
