In the early 1970’s S.Tennenbaum proved that all countable models of PA+∀1−Th(N) are embeddable into the reduced product N /F , where F is the cofinite filter. In this paper we show that if M is a model of PA− + ∀1 − Th(N), and |M | = א1, then M is embeddable into N/D, where D is any regular filter on ω.

This paper deals with the problem of H∞ filter design for nonlinear discretetime systems with time-varying delays via T-S fuzzy model approach. Some delaydependent conditions for fuzzy H∞ filter are proposed in terms of linear matrix inequalities(LMIs), which produce a less conservative result. Finally, one numerical example is given to demonstrate the effectiveness and the benefits of the prop...

We evaluated the efficiency of five membrane filters for recovery of Cryptosporidium parvum oocysts and Giardia lamblia cysts. These filters included the Pall Life Sciences Envirochek (EC) standard filtration and Envirochek high-volume (EC-HV) membrane filters, the Millipore flatbed membrane filter, the Sartorius flatbed membrane filter (SMF), and the Filta-Max (FM) depth filter. Distilled and ...

periodic noises are unwished and spurious signals that create repetitive pattern on images and decreased the visual quality. firstly, this paper investigates various methods for reducing the effects of the periodic noise in digital images. then an adaptive optimum notch filter is proposed. in the proposed method, the regions of noise frequencies are determined by analyzing the spectral of noisy...

This paper investigates the problem of non-fragile L2–L∞ filter design for a kind of Takagi-Sugeno (T-S) fuzzy stochastic system with neutral delay and parameter uncertainties. The addressed problem is the design of a non-fragile fuzzy filter such that the error system is robustly stochastic stable and the filtering error system can tolerant some level of the gain variations in the filter. Base...

In this article, the effect of cells' radius on the behavior of wavelength switching optical filter andthe effect of the radius of the optical filters' key characteristics such as wavelength resonance onan optical filter based on photonic crystals, have been investigated. Currently, the most commonapplied mechanism for designing optical filter based on photonic crystals is using twomechanisms s...

Introduction Vessel enhancement filters applied to 3D MRA data sets prior to rendering as a 2D image may improve visualization of vessel detail. We previously compared several line enhancement filters for intracranial 3D MR angiography images[1]. We examined filters based on discrete lines (e.g., Du and Parker's filter [2]) and on the Hessian matrix (Frangi [3]). We found the Du and Parker filt...

This paper considers the problem of filter design for two-dimensional (2D) discrete-time non-linear systems in Takagi-Sugeno (T-S) fuzzy mode. The to be solved is find a H ∞ model such that filtering error system asymptotically stable. A numerical example employed illustrate validity proposed methods.

In this paper, the design and simulation of a symmetrical waveguide filter are presented based on insertion loss method. The designed WR-34 is operating at 28 GHz, where its dimensions a=4.32mm b=8.64mm, fractional bandwidth 2.15% return level better than 16 dB, frequency range from 22Ghz to 33 GHz. structure 5 th -order bandpass with five resonators six circular inductive irises. order optimiz...