The $t$-channel singularity of a cross-section for binary $2 \to 2$ scattering process occurs when particle exchanged in the $t$ channel is kinematically allowed to be on its mass-shell, that can viewed as sequence two physical subprocesses: two-body decay $1\to and an inverse 1$. We derive conditions present process. A class divergent cross sections Standard Model processes has been determined...

An important feature of most rivers and canals is their habitats for a rich of aquatic vegetation which is extremely important from an environmental and ecological point of view. These variations in habitat mean that it is rare to find a cross-section of a natural channel which has the same roughness along its perimeter. In these channels, flow conditions lead to a complex flow situation with i...

deformation length is one of the most important parameters in cold roll-forming process, which plays a fundamental role in determining the inter-distance between the stations and rate of deformation. deformation length was first introduced by bhattacharyya. he also obtained a closed-form relation for this length in roll-forming of symmetric channel section. in this paper, deformation length in ...

Based on CFD and film theory, filtration’s two-dimensional model of the hollow membrane was established by integrating mass transformation hydrodynamic transportation. Parameters concentration polarization in channel (i.e., solute concentration, factors, layer thickness) were estimated under different hydraulic conditions. In addition, algorithm for thickness has been improved. The results show...

Inkjet developments move towards higher productivity and quality, requiring adjustable small droplet sizes fired at high repetition rates. Normally, maximum jetting efficiency is achieved by tuning the slopes of the driving waveform to the travel times of acoustic waves inside the channel. Important parameters are channel length, compliance of channel cross-section (through its impact on the ef...

I present a calculation of threshold soft-gluon corrections to single top quark production in pp̄ collisions via all partonic processes in the t and s channels and via associated top quark and W boson production. The soft-gluon corrections are formally resummed to all orders, and finite-order expansions of the resummed cross section are calculated through next-to-next-to-next-to-leading order (N...

I present a calculation of threshold soft-gluon corrections to single top quark production in pp̄ collisions via all partonic processes in the t and s channels and via associated top quark and W boson production. The soft-gluon corrections are formally resummed to all orders, and finite-order expansions of the resummed cross section are calculated through next-to-next-to-next-to-leading order (N...

The behavior of a rarefied, compressible flow in long, constant cross section channels provides an opportunity to study complex gas dynamics in a simple geometry that allows analytical solutions. The problem of a rarefied, compressible flow in near unity aspect ratio rectangular cross section channels has been all but ignored despite it being a common flow geometry. We present analytical expres...