Long-range guided wave inspection systems are often used in low frequency– thickness ranges below the cut-off frequencies of Higher wave Modes to simplify data interpretation. In this paper, the potential of high-order guided wave Modes for the inspection of plate structures is considered. The characteristics of high-order lamb wave Modes and their corresponding sensitivity and detectability are investigated. Using a commercially available software package, finite element simulations are carried out to model the propagation of A1 and S1 wave Modes in steel plate. Using a variable angle transducer, experimental pulse– echo measurements are also conducted to evaluate the measurement errors when implementing Higher order Modes A1 and S1 on a 2-mm thick steel plate at 4 MHz. mm. Experimental measurements show that when using S1 mode for short-range measurements, the relative error is less than 10%.

Introduction: Academic faculty members need to emphasize ethical principles in order to improve Higher education, with the understanding of this importance, the current research was conducted with the aim of designing the ethical model of academic faculty members in Iran's Higher education. Material & Methods: This research is a type of qualitative study that uses foundational data theory. The participants, including experts and faculty members of the country's public universities, who were responsible for the promotion of academic members, were selected as key informants through a targeted sampling method of 45 people. Data were collected through semi-structured interviews. The reliability and validity of the data were obtained from the two methods of reviewing the participants and recoding by experts. Data were analyzed by open, central and selective coding. Results: The results showed that the moral model of faculty members in Iran's Higher education is explained in 10 main categories and 27 subcategories. Major and core categories in the form of 6 dimensions of causal conditions including (individual factors, organizational factors), core (cultural-educational, educational ethics, research ethics, scientific-executive), background conditions (Higher education policies, moral activism), intervening conditions (environmental factors), strategies (micro level-university, macro level-Higher education) and consequences (individual and organizational) were elevated to a Higher abstract level and finally the research paradigm model was presented. Conclusion: The regulations for the promotion of academic staff members in Iran require a detailed revision of the content with an ethical and qualitative approach in order to make the indicators of the promotion regulations efficient and effective.

In this paper, a novel low-profile and low cross-polarization metasurface antenna is proposed for 5G mm-wave applications. The proposed antenna consists of two layers, with a slot antenna as the base and a novel metasurface layer on top. The metasurface layer is a 3×3 array of patches. By strategically incorporating slits and stubs within the middle patches, the undesired degenerate mode is separated from the fundamental mode, and Higher-order Modes are suppressed that typically appear in conventional metasurfaces. Additionally, rectangular slots are added in the middle of the corner patches to shift Higher-order Modes to frequencies beyond the desired operating bandwidth, mitigating issues such as beam splitting and beam squint in the radiation patterns. Experimental measurements demonstrate that the proposed metasurface antenna operates over a bandwidth of 25.14% (23.3 GHz to 30 GHz), with a return loss better than 10 dB, a peak gain of 8.1 dB, and an XP level lower than -26 dB and -53 dB at  and  planes, respectively. Compared to conventional metasurface antennas, our design reduces the antenna dimension by 62%, resulting in a compact size of 0.72λ0 × 0.72λ0 × 0.08λ0. Furthermore, we validate the performance of the single-element antenna by employing it in a 2×2 Multiple Input-Multiple Output (MIMO) configuration without requiring additional inter-element spacing. The MIMO antenna exhibits promising performance as well. Overall, our proposed low-profile and low cross-polarization metasurface antenna shows great potential for 5G mm-wave applications, offering improved efficiency and reduced size compared to conventional designs.

We present a new theoretical model for analyzing the impact of Higher order Modes on transverse mode instability in bent Yb-doped fiber amplifiers. The model indicates a comparative analysis of mode instability using the normalized propagation constant in both straight and bent fibers amplifiers. The impact of different bending radii, on bent fibers is investigated in the normalized propagation constant. The results are then compared with the straight fibers. Simulation analysis showed that the interference between the fundamental mode (LP01) and the first Higher order mode (LP11) has the greatest effect on the mode instability, comparing the other Modes. Considering all the existed Modes, the behavior of mode instability in the fibers with different V-numbers are simulated and explained physically.

It is necessary to provide seismic design criteria for structural systems in order to optimally design bending reinforced concrete frames with steel shear wall. Researchers have used energy requirements as one of the most important and efficient tools to measure and minimize cumulative damage to structures, which depend strongly on the time and duration of the earthquake. Therefore, this study attempts to investigate the energy response properties of an equivalent single degree of freedom versus near pulse species acceleration accelerometers to estimate the maximum energy types and its relation to a multi-degree of freedom for three reinforced concrete structures with steel shear walls, low-rise, mid-rise and high-rise under ductile coefficients of 1, 2, 3, 4 and 5. The results of the study of the changes in the ratio of cyclic energy to total energy wasted in the structures show that in the multi-degree system, the period is independent of the periodicity to the extent that the effect of Higher Modes is negligible. Also, by increasing the ductility coefficient, this ratio for the multi-degree system is closer to the results of the one-degree system and, in a sense, increasing the ductility coefficient results in a decrease in the effects of Higher Modes.

In this research, the placement of energy dissipaters at the base of self-centering base-rocking walls has been investigated. For this purpose, structures with 4-, 8-, 12-, 16- and 20-floors were investigated. The nonlinear dynamic behavior of these structures was investigated subjected to 22 Far-Field (FF), 14 Near-Field without Pulse (NF-non Pulselike), and 14 Near-Field with Pulse (NF-Pulselike) seismic ground-motions. The models have been analyzed in two dimensions via OpenSees software. The considered seismic ground-motions are scaled and applied to the structure at DBE and MCE levels. The results showed that changing the location of energy absorbers can be effective in the value of the moment and shear demands of walls as well as the response of residual drift and roof acceleration. By increasing the distance of the energy dissipaters from the middle of the section wall, the moment and shear demands could be reduced about 14% and 13% at the DBE level, and about 19% and 17% at the MCE level, respectively. Furthermore, the reduction values of the moment and shear demands of the structures under NF-Pulselike and DBE or MCE levels have been observed more than other seismic ground-motions. Finally, increasing the distance of the energy absorbers from the middle of the wall, the accelerations of the roof decrease.