A low profile fractal Defected Ground Structure (DGS) antenna is presented for super-wideband (SWB) wireless communication applications. The designed antenna covers a very wide frequency range from 1 to 27.4 GHz (impedance bandwidth of 186%) with |S11|<-10 dB. Moreover, In spite of small electrical dimension of the proposed antenna (0.11 λ× 0.11 λ), a large bandwidth dimension ratio of 15372 is resulted. The SWB operation is achieved by using fractal DGS on the Ground plane to improve the impedance characteristics between adjacent resonant frequencies. The antenna consists of a 34×34×1.6 mm3 FR4 substrate with a dielectric constant of 4.4 and a narrow rectangular radiator. A multi-frequency resonance characteristic is obtained by increasing the fractal slot iterations on the Ground plane. The simulation results are verified by experimental measurements. Measured data are in good agreement with the simulated results. The frequency- and time-domain characteristics of the antenna including impedance matching, far-field patterns, gain, radiation efficiency, group delay, and fidelity factor are presented and discussed. The results indicate that the antenna has good performance over the entire operating bandwidth which make it very potential candidate for integration in SWB wireless communication systems.

A novel geometry of polarization and frequency reconfigurable antenna is proposed in this paper. Proposed antenna consists of an L shaped patch antenna, where arms are separated using PIN-diode. Two parasitic elements, shorted back element and edge tapered Defected Ground Structure with slot are used for achieving wide impedance and axial ratio bandwidth. It acts as circular polarized antenna with 1.183 GHz axial ratio band width and 3.09 GHz impedance bandwidth in ON state of both diodes and act as linear polarized frequency reconfigurable antenna at remaining states of diodes. Proposed antenna can be used in C band wireless applications like RADAR, satellite communication etc.

In this paper, two compact quad-channel and six-channel diplexer are designed and fabricated using Defected microstrip Structure (DMS). This Structure is designed for the desired frequency based on the literature reviews. The proposed configuration is composed of a conventional T-junction divider with two pairs of open bended stubs and dual/tri-band filters. In designing dual band filters, a loop resonator loaded with two stepped-impedance resonator and Defected microstrip Structure. In addition, by adding a pair of open stubs, triband responses easily achieved without increasing the circuit size. The operating mechanism in resonance frequencies by surface current density is obtained. As a result, the multi-channel diplexer occupies a compact size of 0. 13λ g by 0. 13λ g. The measured results are fully in agreement with the simulated predictions indicating that an isolation between channels is more than 29 dB.

Nowadays, the fundamental role of having a purpose for life in physical and mental health has been confirmed. According to victor frankl, presence of a purpose in life gives life a meaning and increases resilience against pains and traumas. The importance of the purpose in life construct reveals the need for a reliable and valid tool to measure it. Crumbaugh and Maholick's purpose in life questionnaire is the first and one of the most applied tools for the assessment of life's purposefulness. The aim of this research is to determine the factor Structure of purpose in life questionnaire. The questionnaire was administered on 206 students who were selected through random stratified sampling at Ferdowsi University of Mashhad. Exploratory factor analysis showed that there are two factors "comprehension" and "purpose" and this finding were confirmed by confirmatory factor analysis. Altogether results of this research showed factor validity of the purpose in life questionnaire with a two factor pattern

This paper presents a new design for a microstrip dual-band band-pass Microstrip filter (BPF) with suitable isolation between two passbands. In this design, a basic Structure is used to achieve a desirable frequency characteristic in the passband. In this regard, Defected Ground Structure (DGS) is implemented to reach optimum parameters of the filter such as bandwidth, return loss, insertion loss. The special features of the filter are the compact size, dual-band design and suitable isolation between two passbands. Variation of the filter characteristics is compared in a table before and after applying DGS. Simulation results are at frequency of 4.84GHz and 3.8GHz. Return loss of -20dB and - 25dB and insertion loss of -0.5dB and -0.9dB are the results of the mentioned frequency, respectively. Also the bandwidth of 87 MHz is achieved for both simulation frequencies. Simulation results are well-matched to the characteristics of the fabricated filter.

Most members of Structures whose useful life has elapsed need to be repaired. These members may be damaged by a variety of factors. Due to the high cost of reconstruction, a large portion of countries’ development budgets are spent annually repairing and rehabilitate these Structures. Compressive members such as columns are one of the most important components in a Structure that play a major role in bearing and transporting all the vertical and lateral loads of the building. Basically, no column can bear to its fullest capacity and is failed by buckling. As a result, many researchers are interested in retrofitting and increasing column strength using new materials and methods. In this investigation, damaged circular hollow section steel columns with vertical and horizontal notches and different percentages of 25, 50, 75 and 100% were examined, also the effects of Carbon Fiber Reinforced Polymer (CFRP) for strengthening has been studied. 26 specimens of steel Circular Hollow Section (CHS) column with the same height and different damage dimensions under compressive load were analyzed by ABAQUS 2016 software. The main problem with slender columns is the global buckling under compressive loads. In order to improve the accuracy of the analysis, a combined method was used to study the post-buckling of the plastic zone. For this purpose, the specimens were first subjected to elastic buckling analysis and then Riks non-linear analysis with global and local imperfections was conducted. The results showed that the defect reduces the bearing capacity and rigidity of the steel columns and horizontal defect is more effective in reducing ultimate load in compare to vertical damage. Horizontal-defective columns experienced ‎significantly lower load bearing capacity than ‎vertical-defective columns and can reduce final load up to 52% ‏ in 100% damage, which this reduction indicated that by increasing damage along the perimeter of the column section, final load decreased sharply. The results also showed that it is critical when the deficiency zone is entirely destroyed, while the effect of damage less than 25% was maximum 2.66%. Columns failure occurred in the form of global and local buckling; in all cases global buckling emerged in the form of the column bending, but the local buckling was different according to the type of the damage. ‎Failure modes of the control column is global ‎buckling with focus on the middle of the ‎column, for non-strengthened specimens with ‎horizontal and 100% damage, local buckling‎‏ ‏is shrinkage of ‎notch edges and for vertical notch is defect ‎edges opening. In specimens with a lower percentage of damage, local buckling occurred for horizontal defects in the form of the inward buckling on the middle and for the vertical ones was outward buckling. ‎Strengthening of columns retrofitted with CFRP presented that these kind of fibers have a positive effect on significant gaining ultimate load capacity, delaying defect buckling, controlling fractures and reducing stresses at the damaged area. CFRP strengthening of Defected cases using 4 layers, restored the reduction of ultimate load up to 51%, which shows the proper performance of the fibers in retrofitting.

Many steel Structures are damaged due to environmental factors such as accidental loads, exhaustion, rust, and phenomena such as cavitation and time passes. Dams’ bottom outlets are one of the important components of these Structures that are subject to numerous hydraulic problems such as cavitation vibration, which causes damage and needs repair. One of the novelties for refining is the use of Carbon Fiber Reinforced Polymer (CFRP). In this paper, the effect of CFRP on gate strengthening under cavitation vibration load and the effect of damage on maximum vibration by using ABAQUS were studied. In order to observe the effects of failure on the maximum vibration of the outlet, two damages were applied to the front or back of the gate. Finally, the damaged gates were reinforced with two layers of CFRP. The outcomes showed that damage resulted in maximum vibration increase and polymer fibers has a significant effect on reducing vibrations and stresses caused by cavitation pressure.

In this paper, a continuum model is proposed so that a Stone-Wales (SW) Defected carbon nanotube (CNT) is replaced by an initial circumferential crack in a continuum cylindrical shell. For this purpose, the critical energy release rate and then the fracture toughness of a Defected CNT are calculated using the results of an existing atomistic-based continuum finite element simulation. Finally, the equivalent crack length is obtained from the fracture toughness. The proposed model can be applicable tovarious kinds of continuum-based simulations of nano-Structures like nano-composites and nano probes where the fracture resistance studies become important. It is concluded for a case study that the armchair (12, 12) CNT containing a SW defect could be replaced with a continuum cylindrical shell with a circumferential crack length of 0.83 nm. Furthermore, the damage variable is discussed to achieve a method for estimating the effective Young's modulus of Defected nanotubes with numerous defects subjected to the progressive damage. This estimation method is evaluated by the atomistic based FE simulation of a double Defected CNT.

The paper presents a feasible way to construct the honeycomb Structured microstrip antenna for UWB (Ultra Wide-band) applications with dual notch characteristic. The antenna designed based on the concept of initial stage of honeycomb nest construction and Defected Ground Structure(DGS) with dual notch for Ultra Wide Bandwidth applications. The two notches for WiMAX (3.5GHz center frequency) and WLAN (5.5 GHz center frequency) are introduced by etching two asymmetrical quarter wavelength slots in the Ground. The compact antenna of size 12 x 20 mm2 with simple geometry achieves very wide bandwidth of 3.1-13.8 GHz(Covers UWB and higher frequency band) with dual notch characteristic.

Design of critical facilities such as nuclear power plant requires an accurate and precise evaluation of seismic demands, as any failure of these facilities poses immense threat to the community. Design complexity of these Structures reinforces the necessity of a robust 3D modeling and analysis of the Structure and the soil-foundation interface. Moreover, it is important to consider the multiple components of Ground motion during time history analysis for a realistic simulation. Present study is focused on investigating the seismic response of a nuclear containment Structure considering nonlinear Winkler-based approach to model the soil–foundation interface using a distributed array of inelastic springs, dashpots and gap elements. It is observed from this study that the natural period of the Structure increases about 10 %, whereas the force demands decreases up to 24 % by considering the soil–Structure interaction. Further, it is observed that foundation deformations, such as rotation and sliding are affected by the embedment ratio, indicating an increase of up to 56 % in these responses for a reduction of embedment from 0.5 to 0.05× the width of the footing.