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The paper presents a method to locate discontinuities in form of transversal cracks in beams, based on vibration measurements. Patterns characterizing frequency changes of the first ten weak-axis bending vibration modes are determined for all possible locations on the structure, using a relation contrived by the authors. It base on the correlation between the strain energy stored in a segment of the beam, which is proportional with the square of
Read moreThis paper proposes a vibration-based damage detection method designed for structural elements subjected to important vertical loads, as columns or pillars. The method is based on the relation existing between the energy stored in the pillar in several vibration modes and the corresponding natural frequencies. For a certain mode, this energy results as the sum of the energies stored in all pillar slices, being dependent on the rigidity and the squared
Read moreIn this paper, a vibration-based damage detection method designed for thin plates is proposed. The method bases on the relation existing between the strain energy stored in the plate in several vibration modes and the respective natural frequencies. For any mode, the strain energy results as sum of the energies stored in all plate elements in that mode. It depends on the square of the mode shape curvature achieved in each element location for the
Read moreWe present a method for deciding when a regular abelian cover of a finite CW-complex has finite Betti numbers. To start with, we describe a natural parameter space for all regular covers of a finite CW-complex X, with group of deck transformations a fixed abelian group A, which in the case of free abelian covers of rank r coincides with the Grassmanian of r-planes in H1(X,Q). Inside this parameter space, there is a subset ΩAi(X) consisting of all
Read moreWe investigate partitioning of integer sequences into heapable subsequences (previously defined and studied by Byers et al. We show that an extension of patience sorting computes the decomposition into a minimal number of heapable subsequences (MHS). We connect this parameter to an interactive particle system, a multiset extension of Hammersley’s process, and investigate its expected value on a random permutation. In contrast with the (well studied)
Read moreCertain phosphatidylcholine acylhydrolases, known as phospholipases, have started to be used for improving the quality of the baked products. The aim of this study was quantification of some volatile compounds from bread loaves, by using recipes with addition of different doses of a commercial available phospholipase, named Belpan FTG. The working methodology consisted of baking tests, by using different doses of phospholipase, like improver. Through
Read moreIn this work, relationships between exogenous phospholipases (PLA) acting solely on the endogenous phospholipid fraction of dough were analyzed. Their influence was determined by chromatography methods, as well as rheological and technological ones. The biochemical and physical modifications in bread dough were studied by using different exogenous PLA in variable doses, without other phospholipids (PL) added.
Read moreA palynological, palynofacies and geochemical investigation conducted on Oligo-Miocene bituminous rocks of the Lower Dysodilic Shale Formation and the Upper Dysodilic Shale Formation (Eastern Carpathians) has allowed recovery of pollen and spore assemblages associated with marine palynofossils (dinoflagellates and prasinophyte algae) and phytoclasts. The general composition of the assemblages suggests an anoxic depositional environment from a distal
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