In conventional WLCSP process, after defining the under bump metal (UBM) layer, a solder ball is dropped in the UBM opening. A subsequent thermal reflow cycle melts the solder ball and cools it in a well defined shape on top of the UBM layer. One draw back of this technology is the fracture or cracking of passivation film that may occur during the solder ball reflow process. The cracks in the p...

Cracking of laser hybrid welding of eccentric fillet joints has been studied for stainless steel. Laser hybrid welding enables narrow deep welds with freedom for shaping the upper weld geometry. The significance of geometrical aspects like weld toe radius, weld surface topography and lack of fusion on fatigue cracking is discussed. Constant amplitude four point bending tests, S/N-curve, topogra...

The paper presents a new analytical model to study the evolution of radial cracking around a corroding steel reinforcement bar embedded in concrete. The concrete cover for the corroding rebar is modelled as a thick-walled cylinder subject to axisymmetrical displacement constraint at the internal boundary generated by expansive corrosion products. A bilinear softening curve reflecting realistic ...

Tensile stress develops in concrete when shrinkage deformations and restraints (internal or external) exist. Utilization of appropriate creep or relaxation functions is crucial for assessing stress and the associated cracking potential in concrete, especially at early ages when chemical and physical properties change rapidly. The existing models, developed either from compressive creep tests or...

We conducted an exploratory investigation in an area where nut-cracking by wild capuchin monkeys is common knowledge among local residents. In addition to observing male and female capuchin monkeys using stones to pound open nuts on stone "anvils," we surveyed the surrounding area and found physical evidence that monkeys cracked nuts on rock outcrops, boulders, and logs (collectively termed anv...

driven erosion could govern tectonic deformation has instigated a decade of geodynamic models and geological studies 5 that explore potential climate–tectonic feedbacks. According to this idea, erosion of mass from Earth’s surface may determine where tectonic deformation is most rapid. Consequently, heavy precipitation, rapid erosion and active faulting are predicted to be spatially correlated ...

Query performance strongly depends on finding an execution plan that touches as few superfluous tuples as possible. The access structures deployed for this purpose, however, are non-discriminative. They assume every subset of the domain being indexed is equally important, and their structures cause a high maintenance overhead during updates. This approach often fails in decision support or scie...