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1.
Russian Journal of General Chemistry - The review article traces the main trends of the synthetic approach to the solution of the problem of overcoming the resistance of pathogenic bacterial...  相似文献   
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The health monitoring has been studied to ensure integrity of design of engine structure by detection, quantification, and prediction of damages. Early detection of faults may allow the downtime of maintenance to be rescheduled, thus preventing sudden shutdown of machines. In cylinder pressure developed, vibrations and noise emissions data provide a rich source of information about condition of engines. Monitoring of vibrations and noise emissions are novel non-intrusive methodologies for which positioning of various transducers are important issue. The presented work shows applicability of these diagnosis methodologies adopted in case of diesel engines. The effects of changing various fuel injection parameters was analyzed. Scope of using non-intrusive technique has been analyzed by changing locations of microphone. Novelty of this worklies in exploring signal processing methods for various locations around the engine test set up. Various frequency ranges of contributing noise and vibration sources were identified. Time-Frequency analysis showed the onset of various cyclic. Based on the identification of various frequency bands, it is possible to device suitable filters in order to extract more information.  相似文献   
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Differential Equations - We consider the direct initial–boundary value problem for the equation of transverse vibrations of a homogeneous beam freely supported at the ends and study the...  相似文献   
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Russian Physics Journal - For a model of decaying dark energy with a fermion (τ-lepton), additional corrections to the classical estimate of the time of falling of particles into a static...  相似文献   
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Sufficient conditions for the compactness in generalized Morrey spaces of the composition of a convolution operator and the operator of multiplication by an essentially bounded function are obtained. Very weak conditions on the function are also obtained under which the commutator of the operator of multiplication by such a function and a convolution operator is compact. The compactness of convolution operators in domains of cone type is investigated.  相似文献   
9.
The curing of oligodienediol with a combined system consisting of a polyisocyanate and a (meth)acrylate-containing compound, which allows it to be structured with the polyisocyanate both at the terminal hydroxyl groups and double bonds due to the (meth)acrylate component, has been studied. The effect of the concentration of the (meth)acrylate component and a peroxide initiator to the degree of cross linking and strength properties of elastomers has been revealed. It has been shown that the participation of oligomer double bonds to form a vulcanization structure, creating the effect of “healing” defects from functional heterogeneity, allows one to increase the degree of cross linking and strength properties of polyurethanes.  相似文献   
10.
It is shown that the countably infinite dimensional pointed vector space (the vector space equipped with a constant) over a finite field has infinitely many first order definable reducts. This implies that the countable homogeneous Boolean-algebra has infinitely many reducts.  相似文献   
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