This paper studies the stress–strain state of an U-shaped expansion bellows under internal-pressure induced load. The is considered as a corrugated shell revolution axisymmetric governing equations have been derived and numerical calculations were carried out. A variant classical theory based upon Lagrangian mechanics was used. finite-difference method applied to solve obtained system ordinary differential equations. ultimate internal pressure resulting in plastic deformations determined....

Due to the widespread use of unmanned aerial vehicles (UAVs) in civil sphere, there is a need improve video image generation quality and transmission technologies, changing streams coding reduce their size quality. Video streaming technologies are moving further towards complicating systems used, which helps received data Higher transmitted signal – more requirements for frequency band increase used. This fact leads us effective compression algorithms that allow combine high with narrow...

Automatic discovery of various types database dependencies (functional, inclusion, matching, and others) is a topic that has received great deal attention in the recent years. The problem formulated as following: having an unexplored dataset, find all hold on this data. Such formulation arises business scientific applications aimed at patterns Metanome pioneering platform which was used to benchmark existing develop new dependency algorithms. It notable since it first attempt unify...

In this paper we consider multidimensional indexing with the additional constraint of lexicographical ordering. order to deal problem discuss two well-known tree data structures: R-tree and B-tree. We study in transactional environment read committed isolation level. To evaluate these approaches had implemented structures (modified GiST ensures concurrency) provide extensive experiments.

Recursive queries and recursive derived tables constitute an important part of the SQL standard. Their efficient processing is for many real-life applications that rely on graph or hierarchy traversal. Position-enabled column-stores offer a novel opportunity to improve run times this type queries. Such systems allow engine explicitly use data positions (row ids) inside its core thus, enable implementations query plan operators. In paper, we present approach significantly speeds up RDBMSes....

In the current paper, we propose to fuse together stored data (tables) and their functional dependencies (FDs) inside a DBMS. We aim make FDs first-class citizens: objects which can be queried used query data. Our idea is allow analysts explore both using database interface. For example, an analyst may interested in such tasks as: "find all rows prevent given dependency from holding", "for table, find that involve attribute", "project attributes functionally determine specified attribute"....