In multi-version databases, updates and deletions of records by transactions require appending a new record to tables rather than performing in-place updates. This mechanism incurs non-negligible performance overhead in the presence of multiple indexes on a table, where changes need to be propagated to all indexes. Additionally, an uncommitted record update will block other active transactions ...

with the advent of cyberspace and development of data and information, virtual cities were presented as new forms of city management in different layers and territories. historic and tourism virtual city are among eight types of virtual cities. in this article some guidelines were presented in order to design and manage them based on tehran tourists' need assessment. theoretical framework ...

introduction: active personal dosimeters (apds) are well accepted as useful and reliable instruments for individual dosimetry measurements. apds have many advantages compared with passive dosimeters for individual external radiation dose assessments. in routine monitoring, occupational exposure is carried out for verification and demonstration of compliance with the regulatory dose limits. so, ...

T his paper explains a novel design approach to improve the performance of the system by compressing the database. The denormalization method joins a group of virtual records from one table into a single physical record. By making the tables and indexes smaller, this method reduces physical I/O operations during loading and querying data. A denormalized table resembles the physical layout of da...

This article is devoted to exploring the properties on logarithmic growth of entire functions represented by Laplace–Stieltjes transforms zero order. In order describe more finely, we introduce some concepts indexes maximum term and center index transforms, establish new inequalities focusing above indexes, order, (lower) type coefficients transforms. Moreover, obtain two estimation forms trans...

In this paper, an extension of the effective index method (EIM) to waveguiding structures containing ideal or saturable third-order nonlinear materials is presented. By applying separation of variables to the dominant field component, the complete problem is subdivided into two scalar problems in the lateral and transverse direction, as in the case of the normal EIM. Making use of the strong tr...

The structure of the circuit equivalent of a practical transformer is developed earlier. The performance parameters of interest can be obtained by solving that circuit for any load conditions. The equivalent circuit parameters are available to the designer of the transformers from the various expressions that he uses for designing the transformers. But for a user these are not available most of...