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Catastrophic failures in engineering metallics frequently occur at high temperatures. A fundamental understanding of plastic deformation and the mechanisms governing the strength‐ductility trade‐off is essential for developing titanium alloys exhibiting superior properties at elevated temperatures. Herein, a metastable β titanium alloy (Ti‐15.1Mo‐3.1Nb‐2.77Al‐0.21Si, wt.%) exhibits unexpected mechanical properties, including an ultimate tensile strength of 863 MPa and a total elongation of 78.3% at 500 °C, accompanied by a continuous and strong work hardening rate (2000–3100 MPa). Dislocation slip and heating play pivotal roles in interlaced parallel α nucleation, and thermal activation promotes interlaced α nucleation. Finally, the dual‐array nano configuration of dense (≈68%) and thin (≈10 nm in width) α phase forms. Hierarchical microstructural evolutions, including β to α phase transformation, nano α grains with dual‐array configurations (interleaved and parallel), and dislocation interaction, contribute to the excellent mechanical properties. These findings reveal that dynamic nano α precipitation with unique dual‐array nano configurations can unveil new prospects for the development of high‐performance metastable titanium alloys at elevated temperatures.

Tracking the maximum power point is a critical issue with solar systems. The power output of the solar panel varies due to variations in irradiance and temperature. Nonuniform irradiation due to partial shading conditions has a direct impact on the characteristics of photovoltaic (PV) systems. To build a diversity of maximum power point tracking algorithms in solar PV systems, this work focuses on perturb and observe, incremental conductance, and fuzzy logic control methodologies. The suggested fuzzy logic control method outperformed the conventional incremental conductance and perturb and observe algorithms with a collection of 49 rules. This paper presents a novel series-parallel-cross-tied PV array configuration with a developed fuzzy methodology. To comment on the performance of a proposed system under various partial shading conditions, a series-parallel PV array configuration has been considered. The simulation result demonstrates that the fuzzy method has a percentage improvement in the global maximum power point tracking efficiency of 24.85% when compared to the perturb and observe method and a 65.5% improvement when compared to the incremental conductance method under long wide partial shading conditions. In the case of the middle partial shading condition, the fuzzy method has a percentage improvement in the global maximum power point tracking efficiency of 12.4% compared to the perturb and observe method and a 60.7% improvement compared to the incremental conductance method.

This study proposes a systematic optimisation process of array configurations for controlled reception pattern antenna arrays. The array consists of a single reference antenna at the centre and four auxiliary antennas at the outer perimeter and is mounted on an anisotropic ground platform with an inter-element spacing of about 0.3λ. Only the mounting angles are adjusted to find the optimum array configuration. The proposed process is evaluated by comparing its performance with the global optimum, a conventional array configuration and random array configurations. The results demonstrate that the proposed process achieves a radiation gain close to the global optimum, and no significant gain reductions are found in the auxiliary antennas.

The tomography technique is an effective way to quantitatively evaluate damage from reconstruction imaging in structure health monitoring (SHM). The reconstruction algorithm for the probabilistic inspection of damage (RAPID) algorithm based on the signal difference coefficient (SDC) feature is a promising approach due to its superior performance. This paper focuses on the influence of different patterns of PZT (Lead Zirconate Titanate) sensor array configurations, i.e., the circular, square, and parallel array, on reconstruction image qualities for evaluating hole and crack damage. Variable shape parameters are applied to account for the unequal damage distances of different actuator-sensor pairs. Considering the directionality scattering fields of cracks, the angular scattering pattern of the SDC values are studied by simulation. The SDC variations for different groups of sensing paths at the same actuator are applied to predict the crack orientation. An improved RAPID algorithm is proposed by defining an additional SDC value of 1 in the path along the predicted crack orientation, which is determined by the point of the actuator causing the minimal SDC variation and the center point of the initial reconstruction image of the crack. The results show that the improved RAPID algorithm is effective for the evaluation of crack damage. Reconstruction image qualities with three PZT sensor array configurations for both holes and cracks are compared. The research is significant for selecting the PZT sensor array configuration in SHM.

Currently, the critical challenge in solar photovoltaic (PV) systems is to make them energy efficient. One of the key factors that can reduce the PV system power output is partial shading conditions (PSCs). The reduction in power output not only depends on a shaded region but also depends on the pattern of shading and physical position of shaded modules in the array. Due to PSCs, mismatch losses are induced between the shaded modules which can cause several peaks in the output power-voltage (P-V) characteristics. The series-parallel (SP), total-cross-tied (TCT), bridge-link (BL), honey-comb (HC), and triple-tied (TT) configurations are considered as conventional configurations, which are severely affected by PSCs and generate more mismatch power losses along with a greater number of local peaks. To reduce the effect of PSCs, hybrid PV array configurations, such as series-parallel: total-cross-tied (SP-TCT), bridge-link: total-cross-tied (BL-TCT), honey-comb: total-cross-tied (HC-TCT) and bridge-link: honey-comb (BL-HC) are proposed. This paper briefly discusses the modeling, simulation and performance evaluation of hybrid and conventional 7 × 7 PV array configurations during different PSCs in a Matlab/Simulink environment. The performance of hybrid and conventional PV configurations are evaluated and compared in terms of global maximum power (GMP), voltage and currents at GMP, open and short circuit voltage and currents, mismatch power loss (MPL), fill factor, efficiency, and a number of local maximum power peaks (LMPPs).

The thinned and sparse beamforming for semicircular FDAs were investigated, where the excitation amplitudes were also considered in thinned semicircular FDAs, and only the elements’ positions were incorporated into the sparse semicircular FDA. Firstly, the transmit–receive model was introduced to handle the inherent time-varying issue of FDA, followed by the thinned and sparse implementations successively. Note that three types of non-linearly varying frequency offsets (FO), i.e., log-FO, sin-FO, and tanh-FO, were adopted during the investigations. Under the same assumption that 50% of the elements should be saved, the sidelobe levels (SLLs) of the thinned semicircular -FDAs were reduced by 5.8 dB, 4.4 dB, and 4.4 dB, and the widths of the mainlobes were all widened by 3° in their angle dimension. Compared with the thinned semicircular FDAs, the phenomenon of mainlobe widening was alleviated in the sparse semicircular FDAs where the SLLs were reduced by 2.2 dB, 3.7 dB and 3.5 dB, and the mainlobes’ widths in the angle dimension were widened by 1°, 0° and 1°, respectively. It should be highlighted that the sparse semicircular FDA with sin-FO did not broaden the mainlobe in the angle dimension. Therefore, it can be concluded that a sparse semicircular FDA is superior over a thinned semicircular FDA, since it can reduce the same cost with a higher array resolution.

In practice, industrial exhaust emissions as well as emissions from automobiles, ships, biomass combustion, etc., can be potential application areas for thermoelectric generation (TEG). However, the structural design of heat exchange equipment is usually limited by the internal flow field, resulting in uneven temperature distribution on the heat exchange equipment’s surface. The resulting mismatch power loss is a major challenge for thermoelectric power generation. In this study, based on the characteristics of the surface temperature distribution of heat exchange equipment in the context of gas emissions, a static reconfiguration scheme is proposed for reconfiguring honeycomb (HC) arrays using the symmetric interval crossing (SIC) method. Based on a fixed interconnect array configuration, the solution requires only a change in the location of the modules and no change in the electrical connections, thus reducing mismatch losses while lowering manufacturing costs. Test experiments are conducted for 6 × 6 TEG arrays, mismatch losses are evaluated for four nonuniform temperature distribution cases, and the performance of seven different TEG array configurations is compared. The findings demonstrate that, in nonuniform temperature distribution scenarios, the SIC method can effectively reduce mismatch losses and has a greater output power than alternative array configurations.

Bipolar electrode corrosion (BPEC), utilizing bipolar electrochemistry, has emerged as a pivotal technique in corrosion research by leveraging potential gradients between two feeder electrodes immersed in electrolyte solutions. This review provides a comprehensive exploration of the methodology, applications, and underlying corrosion mechanisms associated with BPEC, emphasizing its versatility across diverse domains. By establishing an electric field gradient, BPEC facilitates simultaneous oxidation and reduction reactions across a wide electrochemical potential range, typically inducing oxidation near to the negative feeder electrode and reduction adjacent to the positive electrode. The straightforward setup allows efficient screening of corrosion behavior under varied conditions, offering insights into anodic-to-cathodic corrosion dynamics on individual electrodes. Application of BPEC to steel samples reveals insights into pitting, crevice corrosion, general corrosion, and passive behavior, enabling thorough assessment of corrosion phenomena. Integration with sample arrays accelerates comparative studies, while analysis of local current and potential distributions enhances methodological understanding. This review underscores BPEC’s capability for spectroscopic, quantitative, and qualitative assessment of multiple samples in galvanic corrosion studies, providing a streamlined approach to evaluate comparative corrosion behavior within a single experiment. Moreover, evaluating pitting morphology on anodic surfaces offers a straightforward method for quantifying and qualitatively assessing overall corrosion performance across diverse sample sets.

Complex turbulent flow structures are formed within and around box-type artificial reefs (ARs). This study utilizes Particle Image Velocimetry (PIV) and numerical simulation to investigate the flow field within and around ARs of various configurations, such as single- and dual-row arrays. It was found that a small space between reefs causes loading to concentrate on the first reef, while a large space enhances vortex intensity and reduces interference among reefs and promotes vortex development within individual reefs. An optimal space may enlarge the recirculation zone, increase vortex numbers and size, alter the flow distribution, and intensify turbulence, ultimately reshaping the flow characteristics at the reef array. The experimental data show that vortices within ARs attain their maximum strength at an overall reef length to height ratio (Lr/hr) of 3 and reef width to height ratio (Wr/hr) of 0.68. A further increase in Lr/hr weakens the dipole, while an increase in Wr/hr expands the area of high-vorticity and strong turbulence behind the stoss-face openings. These findings provide new insights for the optimum layout of artificial reefs for coastal defense design.

This paper presents an experimental investigation on photovoltaic array (PV array) power output affected by partial shading conditions (PSCs). An experiment setup of a PV array with a series configuration using 2 × 4 photovoltaic modules (PV modules) was built. The power output loss due to the shading effect on the first photovoltaic cells (PV cell) connected with bypass diodes of each photovoltaic module, installed in the PV array in the horizontal direction, was evaluated. Depending on the direction of the sun relative to the PV array configuration, the shading percentage was measured during the test and recorded the current and voltage of the PV array. The performance evaluation of the PV array configurations is referred to with respect to the values of maximum power voltage, the maximum power current, maximum power output, power output losses and fill factor (FF). The experimental results show that 44% shading of the first PV cells affects PV array power output loss by more than 80%.