A novel approach to the problem of regression modeling for fuzzy input-output data is introduced. In order to estimate the parameters of the model, a distance on the space of interval-valued quantities is employed. By minimizing the sum of squared errors, a class of regression models is derived based on the interval-valued data obtained from the a-level sets of fuzzy input-output data. Then, by integrating the obtained parameters of the interval-valued regression models, the optimal values of parameters for the main fuzzy regression model are estimated. Numerical examples and comparison studies are given to clarify the proposed procedure, and to show the performance of the proposed procedure with respect to some common methods.

The use of adaptive feed-forward controllers has proven to be a very successful strategy for controlling noise and vibration in a variety of applications. One reason is that the feed-forward controller is an open loop controller, which can be designed to cancel the undesired noise in a position with any accuracy. However, the feed-forward controller requires an input signal, called a reference signal, correlated to the noise source. Consequently, a single reference controller can only reduce noise radiated from a single noise source. In many applications, there is a need to attenuate noise produced by several noise sources. In this paper, three different structures, single, modulating and individual controller, for multiple input feed-forward controllers have been studied and some design aspects are investigated.

In this article, a multiple input multiple output quadrate frequency bands modified PIFA antenna is introduced for 4G LTE and WLAN applications. The quadrate proposed antenna covers LTE 1800 (1. 71-1. 88 GHz), LTE 1900 (1. 85-1. 99 GHz), UMTS (1. 92-2. 17 GHz), LTE 2300 (2. 305-2. 400 GHz), LTE 2500(2. 50-2. 69 GHz), WLAN (2. 400-2. 484 GHz-5. 15-5. 75 GHz) specified by IEEE 802. 11a/b/g/n/ac and WiMAX (3. 3–3. 6 GHz). Then, the PIFA antenna is used as 2×1 MIMO antenna as a radiation element. The overall dimensions of the single antenna are 50×35×0. 8 mm3 and the MIMO antenna is 50×70×0. 8 mm3 while both are realized on FR4-epoxy substrate. To reduce mutual coupling between PIFA antennas at MIMO configuration, Defected Ground Structure (DGS) along with parasitic double split ring resonator is used. The antenna performance is confirmed by the construction of the antenna prototype and measuring its characteristics in terms of reflection loss coefficient, gain, and radiation properties. The extracted outcomes show a good correlation between the simulation and experimental results that candidate it to satisfy mobile communication requirements.

Estimating the angle of arrival of waves in the low-altitude scenario is a challenging issue in the field of phased array radars. This problem generally occurs when a target moves at low altitude, and the signal received directly from the target coincides with the signal received from its reflection off the ground, simultaneously entering the receiver and disrupting the angle estimation. Many articles have investigated and addressed this issue in phased array radars using high-resolution separation methods. In this paper, we focus on solving this problem in multiple-input multiple-output radars. Specifically, we concentrate on impulse and synthetic aperture radars. The proposed method consists of two steps: first, the range, azimuth angle, and approximate elevation angle of the target are estimated using a matched filter; then, the proposed method is applied around the detected elevation angle to separate the target from its image. The term "image" refers to the reflection of a target from the ground surface, which creates a false target in the receiver. The results obtained demonstrate that the proposed method is capable of effectively separating the target from its image under various conditions.

A novel multiband multiple-input-multiple-output (MIMO) antenna system is proposed. The MIMO antenna system consists of two antenna elements, each of which comprises of three radiators: a driven monopole, an S-shaped strip and an inverted F-shaped strip and occupies footprint of 15x18. 5x0. 8 mm3 only. The driven monopole acts as a quarter-wave monopole and stimulates higher mode resonance. The two strips are excited by electromagnetic coupling from the driven monopole and serve as two additional monopoles leading to a wideband performance for the lower band. The bandwidths (VSWR ≤ 2. 75) achieved for the antenna element are 1. 67 – 2. 2 GHz for the lower band and 2. 28 – 2. 95 GHz for the upper band which cover LTE-1, LTE-2, LTE-3, LTE-7, LTE-40 and WLAN 2. 4 GHz bands. A T-shaped slot and another two slots are introduced to reduce the coupling effect between the two multiband antenna elements. The isolation achieved is higher than 18 dB over the whole band, leading to an envelope correlation coefficient of less than 0. 01. Furthermore, the diversity characteristics of mean effective gains (MEGs) and diversity gain (DG) are also studied. Both the simulated and measured results are shown to illustrate the performance of the proposed multiband MIMO antenna system, and that confirms the suitability for Long Term Evolution (LTE) and wireless local area network (WLAN) handset applications.

The radar design, using the FDA technique, basically resists the well-known ECM methods and increases the power of the ECCM. In this research, ECCM techniques are first discussed. The following is a history of the subject, and it is examined that what are the advantages of phased array radars and frequency arrays and the reason for going to the FDA radars is that the radar is dependent on the distance, in addition to its dependence on the angle. In order to improve the idea of using FDA radars, the FDA-MIMO radars were discussed and according to the modeling and simulation results, it was found that the level of the side lobes in FDA-MIMO method decreased (close to 20 dB) compared with the FDA method, and this advantage means that the arrival of disturbing signals from the angles of side lobes is significantly weakened. On the other hand, as a second advantage, the main beam is sharper than the FDA radar (in the FDA radar, the main beam width is about 11 degrees while in the MIMO-FDA is about 4 degrees). The main idea of this thesis is to use the frequency variation of each element in comparison to the previous element in a randomized manner in the FDA-MIMO method. The results show that the proposed method is sharper than the FDA and linear MIMO-FDA method (about 2.5 degrees), in fact, the accuracy of the resolution of the targets has increased and as a second advantage, it has a lower side lobes level (about 20dB below the linear state).

Purpose: To report a patient with MEWDS.Patient and findings: A 65-year-old man presented with sudden decrease of vision in his right eye. On ophthalmoscopy of the involved eye, numerous small discrete white lesions were detected superficially and deep in the retina around the disc and macula. On visual field examination, enlargement of the blind spot was detected. Fluorescein angiography was unremarkable. On electroretinography, the a-wave was decreased minimally. The patient was followed and after 2 months, significant improvement of visual acuity and visual field was observed.Conclusion: MEWDS is a rare intraocular inflammatory disease of unknown etiology and in contrast to our patient, more frequent in females. The natural course is generally benign with spontaneous disappearance of the lesions and improvement of vision in 6 to 8 weeks.