479 research outputs found
A Contamination Sensor Based on an Array of Microfibers with Nanoscale-Structured Film
A contamination sensor based on an array of microfibers with nanoscale-structured film using evanescent field is proposed and demonstrated theoretically and experimentally. When the molecular contaminants deposit on the nanoscale-structured film, the refractive index of the film will change and the additional loss will be produced due to the disturbance of evanescent field. The possibility of the sensor is demonstrated theoretically by using three-dimensional finite-difference time domain (3D-FDTD). The corresponding experiments have also been carried out in order to demonstrate the theoretical results. Microfibers are fabricated by using hydrogen-oxygen flame-heated scanning fiber drawing method and the nanoscale-structured film coated on the surface of microfibers is deposited by using dip coating process. Then an array of microfibers is assembled to demonstrate the feasibility of the device. The experimental results show that contaminants detection with the device can agree well with the results measured by the laser-scattering particle counter, which demonstrates the feasibility of the new type of contaminant sensor. The device can be used to monitor contaminants on-line in the high-power laser system
contribution in at small
Two-photon annihilate contributions in the process including and intermediate are discussed in a simple
hadronic model. The corrections to the unpolarized cross section and polarized
observables are presented. The results show the two-photon annihilate
correction to unpolarized cross section is small and its angle dependence
becomes weak at small after considering the and
contributions simultaneously, while the correction to is enhanced.Comment: 5 page
Consensus of self-driven agents with avoidance of collisions
In recent years, many efforts have been addressed on collision avoidance of
collectively moving agents. In this paper, we propose a modified version of the
Vicsek model with adaptive speed, which can guarantee the absence of
collisions. However, this strategy leads to an aggregated state with slowly
moving agents. We therefore further introduce a certain repulsion, which
results in both faster consensus and longer safe distance among agents, and
thus provides a powerful mechanism for collective motions in biological and
technological multi-agent systems.Comment: 8 figures, and 7 page
- …