Abstract The article is concerned with the existence of positive solutions a semi-linear elliptic system defined in cylinder $$\Omega =\Omega '\times (0,a)\subset {\mathbb {R}}^n$$ Ω = ′ × ( 0 ,<...

The special variable ratio transmission characteristics and complex tooth profile curve of elliptic gears make it difficult to analyse their characteristics, which restrict the application development elliptical gears. Given that, a characteristic analysis method based on testing is proposed in this paper. By building high-precision gear test rig, distribution laws dynamic lost motion, static b...

The transmission device is composed of rotary motion mechanism and vertical mechanism. synchronous belt planetary gear train upper lower connecting arms to ensure that the product rotates 90° counterclockwise 90°clockwise; cylinder, ball spline technology. flexibly implanted into curriculum with carrier new technology process, which feeds back teaching, takes thought politics as guide implement...

We study Tricomi–Gellerstedt–Keldysh-type fractional elliptic equations and obtain results on the well-posedness of boundary value problems for general positive operators with discrete spectrum Fourier multipliers symbols. As examples, we discuss in half-cylinder, star-shaped graph, half-space other domains.

In this paper some approximate methods for solving the initial-boundary value problem for the heat equation in a cylinder under homogeneous boundary conditions are analyzed. The methods consist in discretizing with respect to time and solving approximately the resulting elliptic problem for fixed time by least squares methods. The approximate solutions will belong to a finite-dimensional subspa...

for the characteristics of horizontal fractures in shallow low-permeability oil layers after hydraulic fracturing in multilayer reservoirs, horizontal fractures are taken equivalent to an elliptical cylinder with the reservoir thickness using the equivalent permeability model; then, upon the elliptic seepage theory, the seepage field which has led by a vertical well with horizontal fractures is...