A semi-analytical elastic stress solution for circular rock stratum based on the theory of curved beam

The circular rock stratum are inevitably encountered in underground mining engineering, which causes waste of resources and dynamic instability. Based on the elastic theory of curved beam and finite-difference computation, a displacement function is presented in polar coordinates for solving two partial differential equations with the boundary conditions in mixed type in elastic, isotropic and homogeneous rock. A semi-analytical elastic stress solution for circular rock stratum is obtained according to the governing equation and stress components in terms of displacement function. The variations of stress distribution with different influencing factors are analyzed, which may lead to a better understanding of the stability of circular rock stratum after coal extractions. Finally, this semi-analytical elastic stress solution is applied to the fold structure in No.2502 mining area and points out the dangerous sites during coal extractions, which provides the basis of construction and safety in coal mine engineering.

Stress Impact of the Annealing Procedure of Cu-Filled TSV Packaging on the Performance of Nano-Scaled MOSFETs Evaluated by an Analytical Solution and FEA-Based Submodeling Technique

Stress-induced performance change in electron packaging architecture is a major concern when the keep-out zone (KOZ) and corresponding integration density of interconnect systems and transistor devices are considered. In this study, a finite element analysis (FEA)-based submodeling approach is demonstrated to analyze the stress-affected zone of through-silicon via (TSV) and its influences on a planar metal oxide semiconductor field transistor (MOSFET) device. The feasibility of the widely adopted analytical solution for TSV stress-affected zone estimation, Lamé radial stress solution, is investigated and compared with the FEA-based submodeling approach. Analytic results reveal that the Lamé stress solution overestimates the TSV-induced stress in the concerned device by over 50%, and the difference in the estimated results of device performance between Lamé stress solution and FEA simulation can reach 22%. Moreover, a silicon–germanium-based lattice mismatch stressor is designed in a silicon p-type MOSFET, and its effects are analyzed and compared with those of TSV residual stress. The S/D stressor dominates the stress status of the device channel. The demonstrated FEA-based submodeling approach is effective in analyzing the stress impact from packaging and device-level components and estimating the KOZ issue in advanced electronic packaging.

The Relationship between Online Dating and Islamic Identity among British Muslims

In Europe and the US, young Muslims are using online matchmaking in growing numbers. Online dating has increasingly become a mainstream activity, in Europe and North America at least. Western Muslims have adapted the idea to suit their needs. For many, online dating offers a low-stress solution to the daunting challenge of finding a partner for marriage in countries where few share their faith and in communities where matchmaking is considered a family affair. This paper will discuss the relationship between Muslim online matchmaking for British Muslims and their Islamic identities with regards to marriage and romantic relationships.

Analytic stress solution for a circular tunnel in half plane with a concentrated force

An analytic stress solution is presented for a circular tunnel problem in a half plane with a concentrated force acting on any position in the field under gravity. The solution uses the complex variable method and the power series method. The influence of the unbalanced force system on the tunnel boundary is considered. The relationship between two analytic functions is established by using surface stress boundary condition. The analytic functions can be determined from the tunnel stress boundary condition. Based on the principle of superposition, the stresses of the surrounding rock can be calculated by superimposing three partial solutions which are obtained separately. The examples give contour plots of the principal stresses in the surrounding rock, focus on the stress distribution on the ground surface and the tunnel boundary and analyze the effect on the stress distribution of some main parameters.