An open photoacoustic detector system, consisting of a high Q cylindrical resonator (Q factor in Nz % 800) and two adjoining variable acoustic filter systems, was tested for pulsed excitation of acoustical modes in a naphthalenelair gas mix by using a 308 nm excimer laser. The outside noise suppression and the signal-to-noise ratio were investigated in a normal laboratory environment in the flo...

original article   electrospun nanofibrous filter media have attracted considerable attention in the last decade. the present study aimed to develop the electrospun pan (polyacrylonitrile) filter media through experimental investigations for application in high-performance air filters. for this purpose, an experimental design was proposed to assess the effect of electrospinning process conditio...

A 3D fuzzy-filtering scheme is proposed for reduction of compression artifacts such as blocking and ringing noises. The proposed scheme incorporates information from temporally-neighboring frames as well as from spatially-neighboring pixels by accounting for the spatio-temporal relationships in the definitions of spatial-rank orders and spread information for the fuzzy-filter. Extra information...

Electrically controlled wavelength switchable terahertz band pass filter based on photonic crystal structures with LC defect layer is proposed and discussed. The wavelength switching can be realized by reorienting liquid crystal molecules through adjusting the applied electric field. Numerical analyses results have shown that the proposed structure has the potential to realize electrically cont...

The problem of efficient and accurate orbit estimation of space trajectories is discussed. For highly sensitive low-fuel trajectories designed to exploit the complex nonlinear dynamics of the three-body problem, it is vital to have accurate state estimation during maneuvers and ability to deal with irregular observation update times. For instance, in Halo-orbit insertion and station keeping man...

We compensate by a prefilter the distortion of an input signal along an electric line modeled by the telegraph equation. The prefilter is based on the so-called flatnessproperty of the telegraph equation. We derive the explicit equation of the filter and illustrate the relevance of our approach by a few simulations.

The aberration of a multipole Wien filter for energy-filtered x-ray photoemission electron microscopy was analyzed and the optimized Fourier components of the electric and magnetic fields for the third-order aperture aberration corrections were obtained. It was found that the third-order aperture aberration correction requires 12 electrodes and magnetic poles.

A neural network controller for improved fuel efficiency of the Toyota Prius hybrid electric vehicle is proposed. A new method to detect and mitigate a battery fault is also presented. The approach is based on recurrent neural networks and includes the extended Kalman filter. The proposed approach is quite general and applicable to other control systems.

slow sand filters are as a proper technology for pre-treatment of raw water, with a fine and medium trubidity in small communities in developing countries. thus, with a minimum operation cost and minimum need for expest bodies have the maximum efficiency. the purpose of this research is carried out to evaluate the efficiency of two processes of horizontal flow roughing filter and vertical flow ...

To achieve a narrow bandwidth optical filter with a wide swept range for new generation optical spectrum analysis (OSA) of high performance optical sensors, an optoelectronic equivalent narrowband filter (OENF) was investigated and a swept optical filter with bandwidth of several MHz and sweep range of several tens of nanometers was built using electric filters and a sweep laser as local oscill...