Contact tracing is a well-established disease control measure that seeks to uncover cases by following chains of infection. This paper examines mathematical models of both single-step and iterative contact tracing schemes and analyses the ability of these procedures to trace core groups and the sensitivity of the intervention to the timescale of tracing. An iterative tracing process is shown to...

This report describes the rheological analysisof the present Ag nanoparticle ink, and confirms that it is suitable for the piezoelectric drop-on-demand printing for both of 1 pL and 10 pL cartridges. The satellite drops and the splashing on the substrate are also discussed for optimization of the nozzle temperature and the jetting voltage. The minimum horizontal and vertical line widths are sho...

As an important branch of non-destructive testing, laser ultrasonic testing has attracted increasing attention in the field material because its instantaneity, non-contact and wide adaptability. Based on finite element method, process laser-excited signal is numerically simulated, influence angled cracks analyzed. In this paper, effects time function, pulse width, spot radius a Gaussian light s...

When a low-voltage circuit breaker (LVCB) breaks high current, the contact erosion caused by arc greatly reduces LVCB’s breaking performance and service lifetime. Therefore, this paper uses AgW alloy contacts as research object, which are commonly used for currents, establishes model an LVCB with current of 14 kA. The considers energy balance surface solidification melting dynamic mesh to deal ...

in this paper, formation of wrinkling in bimetal deep drawing process has been investigated by the analytical, numerical and experimental methods. the effects of width of flange, fillet radii of matrix and punch, clearance of blank holder, contact conditions and relative thickness of two sheets on the number and height of wrinkle waves are studied. clearance and contact conditions have the grea...

For the first time we report that by introducing sub-nm roughness on a Si surface, the energy coupling between a single layer graphene (SLG) and the Si substrate can be improved substantially. This is contrary to the traditional view that a rough surface contact will weaken the energy coupling, rather than improve it. Periodical grooves of 2 nm width and 2 nm spacing are introduced on the surfa...

abstract:any effects of wood coating with different compounds as nano-zinc, nano-chitosan, chitosan, silicon oil and flaxseed oil on surface properties as; wood color change, surface roughness and wettability were studied in the current research work. for this purpose, sample boards of beech wood were cut into sizes of 2×10×20cm. the specimens were coated with the noticed coatings and tested fo...