Search Results (1,971)

In existing research on non-contact damage by high-power microwave (HPM) systems to electronic systems such as seekers, challenges include high risk, high cost, and a scarcity of HPM-specific damage assessment models. To address this, this paper proposes a multi-port HPM damage level assessment model based on interval-valued intuitionistic fuzzy (IVIF) sets. Firstly, electromagnetic modeling and field-circuit coupling simulation of multi-target structures provide input data from field-circuit simulations. Secondly, a multi-indicator fuzzy matrix reflecting system damage uncertainty is formed using interval fuzzy membership functions. Thirdly, an information entropy-driven dynamic weighting mechanism weights each indicator’s fuzzy distribution characteristics, and hybrid weights are constructed by dynamic and fixed weights to optimize parameter range rationality. Finally, using hybrid weights and the exponential damage mapping function, we achieve probabilistic fusion of multiple parameters and determine damage levels from the probability results. Assessment shows that under the same incident field strength of 25 kV/m, electromagnetic simulation software-based simulation assigns a composite damage probability of 0.85 to L-band Port 5 and 0.096 to X-band Port 6, highlighting the contrast between the dominant L-band hotspot (Port 5) and the low X-band response at Port 6 under identical irradiation. Full article

To eliminate the sensitivity of frequency-swept interferometric ranging to Doppler-induced errors and laser frequency-sweeping nonlinearities, as well as to overcome the limitations of existing suppression strategies—such as strict synchronization requirements in dual-sweep configurations and increased system complexity in single-sweep schemes with auxiliary optical paths—a microwave photonic frequency-swept interferometric method based on dual-sideband modulation is proposed. In the proposed approach, an electro-optic modulator is utilized to generate a pair of frequency-symmetric optical sidebands with opposite chirp characteristics. Owing to the bidirectional symmetry of the frequency sweeps, Doppler-induced and frequency-sweeping nonlinearity induced errors in the two sidebands exhibit equal magnitudes but opposite signs, enabling intrinsic cancellation of Doppler effects as well as compensation of system-nonlinearity induced errors. Experimental validation demonstrates that, compared with conventional frequency-swept interferometric techniques, the proposed method achieves approximately 35% improvement in measurement accuracy under dynamic conditions, while preserving high resolution and strong robustness against environmental perturbations. The results indicate that the proposed scheme offers a simple, effective, and practical solution for high-precision dynamic ranging in high-speed and complex environments. Full article

Isocyanides constitute a valuable class of organic compounds widely employed in multicomponent reactions (MCRs), heterocycle synthesis, and drug discovery. However, their broader application is limited by low commercial availability and hazardous classical synthetic methods. Herein, we report a greener microwave-assisted protocol for the efficient synthesis of isocyanides through a modified Hofmann carbylamine reaction. The methodology is based on the in situ generation of dichlorocarbene from near-stoichiometric amounts of chloroform and sodium hydroxide, using Span^® 80 (sorbitan monooleate) as a biodegradable phase-transfer catalyst under microwave irradiation. Importantly, the protocol eliminates the need for aqueous workup procedures, thereby reducing waste generation and improving the overall sustainability of the process. A broad range of aliphatic-, aromatic-, and amino-acid-derived isocyanides was obtained in moderate-to-excellent isolated yields (43–96%) within 30 min, without isolation of intermediates. Compared with conventional approaches, the proposed methodology avoids toxic dehydrating agents such as POCl₃ and phosgene, eliminates the need for formamide precursors, and reduces hazardous by-products associated with dehydration processes. The protocol is operationally simple, scalable, and represents a practical, convergent, and environmentally more benign alternative for isocyanide synthesis. Full article

Among the various types of magnetic field sensors, only a few can detect magnetic fields non-intrusively, and even fewer offer ultra-wideband capability with an extreme dynamic range. In this report, we present a magneto-optic B-field probe that can detect a magnetic field with negligible perturbation to the field it detects. The probe is compact and has a frequency bandwidth of DC to 2 GHz. Furthermore, this technique achieves a dynamic range that significantly exceeds 100 dB by utilizing different magneto-optic materials. The device is an intrinsic vector-field sensor that can measure the direction, amplitude, and phase of a time-varying magnetic field. It offers several advantages, including a compact size, high sensitivity, room-temperature operation, a wide dynamic range, and vector-sensing capabilities across a broad frequency range. These features make it suitable for a variety of applications, such as RF and microwave testing, extreme low-frequency applications, and biomedical uses. Full article

Advanced Driver Assistance Systems (ADAS) can exhibit perception limitations involving large or stationary vehicles, occluded downstream hazards, and the finite detection range of onboard radar. This study proposes a microwave signal conversion based support framework comprising a vehicle-mounted V2V–V2V system and a roadside I2I–I2V system. The algorithms convert and retransmit radar signals according to vehicle speed and spacing states or downstream congestion, while longitudinal responses were behaviorally represented in VISSIM-COM through conditional Desired Speed modification for equipped trucks and buses. A calibrated 12-km Seoul Tollgate corridor was evaluated using V2V–V2V market penetration rates of 0–100%, a binary I2I–I2V condition, and a combined full-deployment scenario. Run-level TTC and conflict frequency were summarized using means, standard deviations, and 95% confidence intervals, and both measures were compared using two-sided paired t-tests. Increasing V2V–V2V penetration was associated with higher TTC and fewer conflicts. Within the tollgate influence area, combined deployment increased mean TTC from 0.72 to 1.27 s and reduced mean conflict frequency from 1486 to 764; both paired comparisons were statistically significant (p < 0.001). These findings suggest potential surrogate-safety benefits from coordinating vehicle- and infrastructure-based recognition support and advance speed adjustment. Full article

Maceration is one of the most important tools available to winemakers for shaping the chemical composition, sensory profile, and overall style of red wines. However, understanding the consequences of different maceration choices remains challenging due to the diversity of available techniques, the complexity of extraction phenomena, and the fragmented nature of the available literature, which spans a wide range of technological strategies, cultivars, vintages, winemaking conditions, and analytical approaches. This review thus provides a comprehensive overview of traditional, advanced and emerging maceration techniques used in red winemaking. Conventional approaches, including pre-fermentative cold maceration, fermentative maceration, extended post-fermentative maceration, whole-bunch fermentation, and carbonic maceration, are discussed alongside technological modifications such as cryoextraction, thermovinification, flesh-release and Accentuated Cut Edges, as well as emerging and non-thermal technologies including pulsed electric fields, ultrasound, high-pressure processing, microwaves and ohmic heating. Particular attention is given to the mechanisms governing extraction, with emphasis on how processing conditions and tissue-disruption phenomena influence grape cell wall integrity, membrane permeability, and the release of targeted constituents from different grape tissues. Finally, the advantages, limitations, and practical implications of each technique are highlighted for researchers and winemakers, indicating the need for an integrated consideration of chemical, microbiological, sensory, technological, and economic factors when optimizing red wine production. Full article

The rapid global transition toward sustainable food systems has intensified interest in alternative protein ingredients derived from both terrestrial plants and blue foods. However, a critical bottleneck in the commercialization of these proteins is the stabilization of flavor profiles during dehydration. Drying technologies ranging from conventional hot-air and heat pump drying to microwave and vacuum freeze-drying inevitably induce structural reorganization and oxidative modifications. These transformations fundamentally modulate how volatile flavor compounds are bound, retained, and released within the food matrix. This review proposes a comprehensive structure–process–function framework that mechanistically connects intrinsic protein architectures, drying-induced denaturation, and flavor-binding behavior. The review first contrasts globular plant proteins (e.g., soy, pea, and emerging tropical crops) with fibrous marine myofibrillar and collagenous proteins, emphasizing their distinct hierarchies, amino acid compositions, and oxidative vulnerabilities. It then critically evaluates how varying drying modalities drive protein unfolding, aggregation, and carbonylation, and how these transformations alter binding pocket accessibility, surface hydrophobicity, and lipid–protein–flavor crosstalk. Furthermore, it highlights the emerging role of hybrid plant–marine protein matrices as a strategy to optimize techno-functionality. By integrating structural biophysics with computational approaches such as molecular docking and structure-based modeling, this review provides a predictive conceptual map for designing flavor–protein interactions under specific dehydration histories. Ultimately, the proposed framework offers practical design principles for selecting protein sources and tailoring drying strategies to produce high-quality, sensorially superior, and sustainable next-generation food products. Full article

In the present paper, we studied the interaction of microwave radiation with conductive indium tin oxide (ITO) coatings deposited on a borosilicate glass. The experiments were carried out with the ITO films, the thickness of which varied in the range from 85 to 607 nm. The transmittance and reflectivity of the ITO film/K108 glass structures were measured in the frequency region from 3 to 23 GHz. Theoretical modeling of the spectra was performed by means of the transfer matrix method. It was shown that for a given thickness of the glass substrate, the transmission and reflection spectra of the ITO film/K108 glass structures were fully determined by only one parameter of the ITO film, namely, its DC sheet resistivity. The considered model predicts an increase in maximum microwave shielding effectiveness up to 45.6 dB with a decrease in DC sheet resistivity to 1 Ohm/sq. ITO coatings with DC sheet resistivities down to 2.3 Ohm/sq have been experimentally investigated. The model microwave transmittance and reflectivity spectra were in good agreement with the experimental ones. In particular, the coefficient of determination for the transmittance spectra was rather high: R² > 0.93. It was experimentally demonstrated that applying antireflective coatings on both sides of the ITO film/K108 glass microwave shielding filter significantly improved its transparency in the operating optical range. A filter has been created that provides microwave shielding effectiveness of 38.7 dB with an average transmission coefficient of 0.81 in the visible range. Full article

The quantity and bioavailability of iron (Fe) in commercial chicken eggs have been subject to ongoing debate. Understanding the chemical form of Fe in eggs, and how different laying conditions or cooking environments may alter chemical form is important to guide future studies of Fe bioavailability. To address these unanswered questions, this study aimed to accurately quantify and characterise Fe speciation (including haem and non-haem Fe) in egg yolk, albumen and whole eggs (mixed yolk and albumen), in both raw and cooked eggs. Eggs were obtained from four different hen housing systems: free-range, cage, barn and organic. Total Fe was measured using microwave plasma atomic emission spectrometry, and X-ray absorption near-edge structure spectroscopy was used to quantify the relative proportions of different chemical forms of Fe (Fe speciation). These analyses were conducted on raw albumen, yolk, and whole egg samples (combined yolk and albumen) from eggs produced across all housing systems, as well as on baked and boiled albumen, yolk, and whole egg samples from free-range eggs. Haem Fe was not detected by the analytical methods used, confirming that eggs are not a nutritionally relevant source of haem Fe. Mixing yolk and albumen alters Fe speciation, decreasing relative phosphate coordination of Fe and increasing Fe associated with protein carboxylate and chloride groups. Subsequent baking causes a significant reduction in carboxylate- and chloride-bound Fe, accompanied by an increase in sulfur-bound Fe. Boiling eggs was found to have minimal effects on Fe speciation. Despite contributing little Fe, albumen plays an important role in modulating Fe speciation, which may subsequently impact bioavailability. Cooking eggs changes the Fe speciation, particularly increasing the amount of Fe–S coordination, which should be taken into consideration for future study design when assessing Fe bioavailability. Full article

Following the integrated optical assembly and single printed circuit board co-layout design concept for electrical circuits, this paper develops a field-programmable gate array (FPGA) based, miniaturized, eight-channel microwave photonic transceiver stabilization system for the joint regulation of lasers and Mach–Zehnder modulators (MZMs). The integrated single-board hardware enables high-precision, high-reliability automatic temperature control (ATC), automatic power control (APC), and arbitrary closed-loop control of the MZMs bias point, overcoming the drawbacks of discrete single-channel, independent control schemes reported in previous works, which lack expandability for large radar arrays. The laser sub-module supports continuously adjustable drive current and multi-level protection, achieving wavelength stability of 0.01 nm and an output optical power fluctuation of less than 0.02%. The MZM control unit delivers wide-range, high-stability bias drift suppression with arbitrary bias point stability up to 0.05 dB. All static and dynamic performance indicators of the proposed module are characterized using a dedicated experimental setup comprising optical power meters, optical spectrum analyzers, temperature cycling chambers, and vector signal analyzers. Leveraging FPGA-based parallel hardware logic, the system features low latency, low jitter, cross-channel mismatch compensation, and excellent timing synchronization, with a compact overall footprint of 180 mm × 120 mm that matches the size of radar antenna panels and supports flexible array scaling. The proposed integrated module meets the low-noise, high-reliability, and high-integration requirements of radio-over-fiber links in microwave photonic radars. It effectively advances the practical engineering deployment of microwave photonic radar systems. Full article

This study investigates the feasibility of using an etched addressed fiber Bragg structure (EAFBS) as the sensing element in a microwave-photonic system for local pH monitoring. A theoretical model is developed that incorporates transmission-spectrum analysis of the addressed Bragg structure and evaluation of the effective refractive index of the guided mode as a function of the surrounding medium parameters. The model establishes a relationship between the refractive index of the surrounding medium and the spectral response of the EAFBS. Using the proposed mathematical model, numerical simulations are performed for three pH ranges corresponding to various liquid media. The results of numerical studies show that in all in the pH ranges, the address frequency varies nearly linearly, with a sensitivity of approximately 1.66 GHz/pH (pH range of 4–7), 2.64 GHz/pH (pH range of 7–10), and 1.92 GHz/pH (pH range of 10–13), whereas its temperature dependence in the range of 35–45 °C is approximately 1.06 GHz/°C. These results indicate that the proposed EAFBS-based approach can provide a foundation for high-speed pH sensing systems with a simplified interrogation scheme and potential capability for frequency-division multiplexing. Full article

In this manuscript, a graphene-based four-port linear MIMO antenna is proposed for terahertz (THz) applications. The antenna is designed on a polyimide substrate with a compact footprint of 60 µm × 240 µm × 4 µm. A modified triangular patch with a tip-fed configuration is employed to enhance asymmetric current distribution, enabling dual-band operation at 2.88 THz and 4.36 THz. A parametric analysis is carried out by varying the chemical potential and relaxation time of graphene to optimize the antenna performance in terms of S-parameters. The proposed design achieves an inter-element isolation > 20 dB, with a realized gain exceeding 3.28 dBi and radiation efficiency above 65% across both operating bands. Furthermore, key MIMO diversity parameters are evaluated, demonstrating an envelope correlation coefficient (ECC) ≤ 0.008 and channel capacity loss (CCL) ≤ 0.27 bits/s/Hz over the entire operating range. The total active reflection coefficient (TARC) remains stable under varying excitation phase conditions, indicating minimal mutual coupling between adjacent ports. An equivalent circuit model is also developed to validate the simulated results. The antenna is analyzed using CST Microwave Studio, and the obtained results confirm its suitability for emerging THz wireless applications. Full article

Ferrite is an essential functional material for high-power nonreciprocal microwave components, such as circulators and isolators, and its secondary electron emission (SEE) property is critical for suppressing the multipactor effect under vacuum conditions. In this work, we propose a surface engineering strategy based on periodic raised microstructures to regulate the secondary electron yield (SEY) of ferrite coatings/substrates. A Monte Carlo-based numerical method is developed to calculate the SEY of ferrite with hexagonal and annular microprotrusions of varying heights and geometric parameters. The dependence of SEY on microstructure dimensions is systematically analyzed. Spinel ferrite samples with designed microstructures are fabricated via mechanical processing. For hexagonal column arrays with a height of 1.5 mm, a side length of 0.5 mm, and a pitch of 1.67 mm, the maximum SEY is reduced from 2.4 (smooth surface) to 1.7 while the annular concentric protrusion arrays decrease the maximum SEY to 2.1. Effective suppression is achieved over the entire incident energy range for both microstructural designs. Despite a lower reduction, the annular arrays offer geometrically isotropic electron trapping, which may be advantageous for devices with circular or coaxial cavity geometries where directional dependence of the surface texture is undesirable. The results demonstrate that tailored surface microstructures can significantly mitigate SEE of ferrite, providing a promising route for developing high-performance ferrite coatings toward multipactor suppression in space microwave devices. Full article

Purpose: This study aimed to develop and validate a comprehensive multi-sensor integrated platform for objective assessment of skeletal muscle recovery kinetics following exercise-induced muscle damage (EIMD), combining biomechanical, thermal, and biochemical monitoring modalities. Methods: Forty elite male athletes were randomized to microwave diathermy (MWD, n = 20, 2.45 GHz, 160 W, 45 min/session) or control (n = 20) groups. Time-synchronized multi-sensor assessments at baseline, 24 h, 48 h, and 72 h post-EIMD included: biomechanical sensors (knee flexion range of motion via goniometry and isokinetic peak torque), thermal sensor (skin surface temperature via infrared thermometry), and biochemical sensor array (serum CK, IL-6, and CRP via high-sensitivity ELISA). Two-way repeated-measures ANOVA with Bonferroni correction examined group × time interactions across all sensor channels. Results: Pre-study validation confirmed high reliability across all sensor modalities. Cross-modality concordance analysis revealed significant correlations between biomechanical and biochemical recovery trajectories (isokinetic torque vs. IL-6: r = −0.73, p < 0.001; pain vs. IL-6: r = 0.68, p < 0.001). MWD intervention demonstrated accelerated recovery across all sensor channels: complete ROM recovery by 48 h (MWDG post-2 vs. baseline, p > 0.05; CG post-3 43% below baseline, p < 0.001), complete isokinetic torque restoration by 72 h (MWDG post-3 vs. baseline, p > 0.05; CG 44% below baseline, p < 0.001), and near-complete pain resolution (VAS 1.70 ± 2.50 mm, p < 0.05). Biomarker sensors demonstrated differential recovery kinetics: IL-6 normalized by 48 h (1.52 ± 0.14 pg/mL, p > 0.05 vs. baseline), CRP approached baseline by 72 h (0.73 ± 0.24 mg/L, p > 0.05), while CK remained elevated at post-3 (169.70 ± 22.58 U/L, 30% above baseline, p < 0.001), indicating incomplete myofiber membrane integrity recovery despite resolution of systemic inflammatory markers. The control group exhibited persistent deficits across all sensor channels with no clinically meaningful recovery. Conclusions: This study validated an integrated multi-sensor platform for recovery assessment. Microwave diathermy demonstrated efficacy by 72 h with complete functional recovery and inflammatory normalization (though CK remained elevated). Cross-modality concordance (r = −0.73 to 0.68) confirmed superior assessment compared to single-modality approaches. This laboratory-based methodology provides a framework for future portable sensor systems in athletic surveillance. Full article

Translating Synthetic aperture radar (SAR) images into optical images is intrinsically ill-posed because microwave backscatter and optical reflectance describe different physical properties of the observed scene. Although frequency-domain modeling has been introduced into diffusion-based translation, existing methods mainly rely on independent weighting of individual Fourier coefficients and provide limited modeling of interactions among neighboring frequencies and feature channels. To address this limitation, we propose dualCDM, a conditional diffusion model that jointly exploits spatial- and frequency-domain representations. In the diffusion backbone, a spatial-frequency hybrid residual block (SFHRB) combines a spatial convolution branch with complex-valued convolution in the Fourier domain. The complex convolution aggregates neighboring Fourier coefficients across all input feature channels, enabling local cross-frequency and cross-channel modeling, while its response is modulated by the diffusion timestep. In the SAR conditional encoder, an adaptive frequency-domain feature recalibration block (AFFRB) predicts input-dependent real-valued gains from magnitude and trigonometric phase representations of intermediate GRD features. These gains adaptively recalibrate the complex frequency responses without introducing an additional phase shift, while the residual connection preserves the original conditional information. A dual-domain objective further constrains both the predicted diffusion noise and the one-step optical reconstruction in the spatial and frequency domains. We also construct the S1S2 dataset using 16-bit Sentinel-2 reflectance data, retaining the original 0–10,000 value range and including the near-infrared band. Experiments on SEN1-2 and S1S2 show that dualCDM improves radiometric accuracy, spectral consistency, and structural preservation over six representative methods. Paired statistical tests further confirm significant improvements over the strongest competing method across all six evaluation metrics on both datasets. Full article