Here we consider some non-autonomous ordinary differential equations of order n and present some results and theorems on the existence of periodic solutions for them, which are sufficient conditions, section 1. Also we include generalizations of these results to vector differential equations and examinations of some practical examples by numerical simulation, section 2. For some special cases t...

The paper presents solutions for generalization problems using least squares adjustment theory. This concept allows for the introduction of several observations in terms of constraints and for a holistic solution of all these – possibly contrary and competing – constraints. Two examples are used to demonstrate the validity of this approach: the simplification of building ground plans and the di...

Transactional objects combine the performance of classical concurrent with high-level programmability transactional memory. However, verifying correctness is tricky, requiring reasoning simultaneously about objects, which guarantee atomicity individual methods—the property known as linearizability—and software-transactional-memory libraries, user-defined sequences method calls—or serializabilit...

In this paper, buckling behavior of symmetric functionally graded plates resting on elastic foundation is investigated and their critical buckling load in different conditions is calculated and compared. Plate governing equations are derived using the principle of minimum potential energy. Afterwards, displacement field is solved using Galerkin method and the proposed process is examined throug...

In this article, three new green's functions are presented for a narrow strip line (not a thin wire) inside or on a homogeneous dielectric, supposing quasi-TEM dominant mode. These functions have no singularity in contrast to so far presented ones, so that they can be used easily to determine the capacitance matrix of multi-layer and single-layer homogeneous coupled microstrip lines. To obtain ...