Search Results (4,089)

Quantum image transmission over noisy communication channels remains a challenge due to the fragility of quantum states and their susceptibility to channel impairments. Existing quantum encoding schemes often exhibit limited noise resilience, while advanced approaches introduce computational and implementation complexity. To address these limitations, this paper proposes a circular polarization-based quantum encoding framework for image transmission over error-prone channels. In the proposed approach, source images are compressed and source-encoded using standard image coding formats, including the joint photographic experts group (JPEG) standard and the high-efficiency image file format (HEIF), and converted into classical bitstreams. The resulting bitstreams are protected using channel coding and mapped onto quantum states via circular polarization representations, where left- and right-hand circularly polarized states encode binary information. The encoded quantum states are transmitted over noisy quantum channels to model channel impairments. At the receiver, appropriate quantum decoding and channel decoding operations are applied to recover the classical bitstream, followed by source decoding to reconstruct the image. The performance of the proposed framework is evaluated using image quality metrics, including peak signal-to-noise ratio (PSNR), structural similarity index measure (SSIM), and universal quality index (UQI). Simulation results demonstrate that the proposed circular polarization-based encoding scheme outperforms existing quantum image encoding techniques, achieving channel SNR gains of 4 dB over state-of-the-art Hadamard-based encoding and 3 dB over frequency-domain quantum encoding methods under severe noise conditions. These results indicate that circular polarization-based quantum encoding provides improved noise robustness and reconstruction fidelity for practical quantum image transmission systems. Full article

Fractures are becoming a bigger and bigger global health problem, with an estimated 178 million new cases each year and 455 million people living with disabilities caused by fractures. Donor site morbidity, the risk of immune rejection, and limited functional integration all make current grafting techniques less effective. Biomaterials that come from nature, like collagen, gelatin, chitosan, alginate, hyaluronic acid (HA), and silk fibroin, have become promising scaffolds because they are bioactive, mimic the extracellular matrix (ECM), and can be broken down by enzymes. Crosslinking and composite reinforcement can greatly change how well they work. For example, collagen scaffolds that are highly crosslinked with glutaraldehyde keep up to 51.9% of their tensile strength after being exposed to enzymes, while non-crosslinked scaffolds only keep 12% of their strength. Chitosan–hydroxyapatite matrices, on the other hand, can reach compressive strengths of 2–12 MPa, which is close to the strength of cancellous bone. Additive manufacturing and 4D printing allow for precise control of structures and the ability to change their shape over time, which helps with vascularization and mechanical adaptation. Injectable and in situ-forming hydrogels show clinically important results, such as filling 85% of osteochondral defects in rabbits, improving left ventricular ejection fraction by up to 9% in large-animal cardiac models, and speeding up healing by 25–40% in chronic wounds. Even with these improvements, it is still hard to get batch consistency, a standardized way to test mechanical properties, and production that meets GMP (Good Manufacturing Practices) standards and can be scaled up. Full article

To enhance the utilization rate and mechanical performance of recycled sand (RS) in extrusion-based 3D printing, this study investigates the influence of varying incorporation ratios of RS across two particle size fractions: 0.075–1.18 mm (RS01) and 1.18–2.36 mm (RS12). The RS utilization rate was determined via the material balance method, while microstructural mechanisms were analyzed using scanning electron microscopy and Vickers microhardness testing. The results indicate that: a combination of 75% RS01 and 25% RS12 achieves the maximum RS utilization rate of 84.3%. At an RS12/RS01 ratio of 1:3, the printed specimens exhibit the smallest tilt angles in bidirectional buildability tests, measuring 7.6° and 7.2°, with corresponding tan θ values of 0.066 and 0.063. Compared to mortar with 100% RS01, this optimized mixture yields average increases of 36.5% in compressive strength, 40.7% in flexural strength, and 6.8% in interlayer splitting strength. Analysis of variance indicates that different particle size combinations have a significant effect on the mechanical properties. Microhardness analysis reveals that the combination of 75% RS01 and 25% RS12 achieves a minimum interfacial transition zone width of 46 µm. Utilizing larger-particle-size RS in 3D printing effectively enhances its utilization rate while maintaining satisfactory printability and mechanical properties. Full article

Traditional ready-to-wear garments can mostly not conform to different body shapes because of the adoption of the generic sizing system, which leads to the local strain of concentration and morphological misfit. Auxetic structures, which have a negative Poisson’s ratio, permit enhanced redistribution of stress and geometry and allow deformation. Two auxetic knitted structures were developed by using 100% polyester and 100% nylon yarns with a fabric density of 41 Wales and 40 courses per inch. Characterization of the initial fabrics involved checking the behavior of negative Poisson’s ratio (NPR) where the polyester line (P1) structure shows the highest auxeticity, with a NPR of approximately −0.4 and peak strain reductions of 80–90%, as well as air permeability, moisture management, bend test, compression, roughness, friction properties and stiffness tests to check the mechanical and comfort-related performances. The standardized tunic garment was modeled in CLO 3D on three female body shapes—hourglass, pear and rectangle—with a constant size of 34. The fit map showed a strain of 91.49% in auxetic and 509.75% in single-jersey fabric at the hip area of the pear body shape when measuring fabric and body interaction. The findings indicate lower peak strain levels, which ascertain that increased adaptability is possible and support its use in the development of adaptive ready-to-wear garments. Full article

Boundary Layer Ingestion propulsors operate in an adverse aerodynamic environment with high levels of distortion. With the purpose of extending the operating range of transonic fan rotors for BLI applications, in this paper we present an optimisation study focused on blade profiles design under different working conditions. Quasi-2D blade sections are optimised using a genetic algorithm and numerical simulations, by varying the camberline and thickness distribution. A method to efficiently achieve a combination of total pressure ratio at a given relative inlet Mach number is devised. The isentropic efficiency is optimised at the design point, concurrently with the stall total pressure ratio at a lower inlet Mach number, in a multi-objective fashion. Pareto-optimal profiles exhibit a moderate leading edge concavity for high efficiency and a straighter fore part with increased trailing edge deflection for higher compression at stall. Optimised airfoils are used in a preliminary three-dimensional evaluation with a realistic BLI inflow, in which the unsteady full-annulus analysis corroborates the approach of the sectional optimisation, also showing the possibility of estimating the integral performance of the machine with a simplified approach based on a single-passage simulation with a circumferential-averaged inflow distribution. Full article

Children are often underserved by adult-oriented oral medicines, leading to off-label use and dosage-form manipulation that may compromise dosing accuracy. This review summarises recent advances in paediatric orodispersible tablets (ODTs), focusing on manufacturing technologies, superdisintegrants, taste masking, and in vitro disintegration testing. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidance and a protocol registered with the International Platform of Registered Systematic Review and Meta-analysis Protocols (registration number INPLASY2025110022), we searched PubMed, EMBASE, MEDLINE, Scopus, and Google Scholar for experimental studies on paediatric-relevant ODT formulation and evaluation. Two reviewers screened studies and extracted data on manufacturing methods, excipients, disintegration/dissolution testing, and key outcomes. Risk of bias was assessed using a six-domain framework. Overall, 65 studies met the inclusion criteria for this review. Direct compression was the dominant method, with freeze-drying, sublimation, spray-drying, nanoparticle-in-tablet systems, and semi-solid extrusion/3D printing also reported. Crospovidone, croscarmellose sodium, and sodium starch glycolate were the most common superdisintegrants, while natural and co-processed disintegrants showed promise as cost-effective alternatives. Disintegration was usually assessed using pharmacopoeial methods, with some modified set-ups to better simulate oral conditions. Paediatric ODT development is advancing rapidly. Broader translation requires harmonised disintegration testing, age-stratified acceptability reporting, and GMP-ready workflows, alongside benchmarking of superdisintegrants and attention to dose flexibility, packaging, and affordability. Full article

Against the backdrop of dual-carbon goals and resource constraints, the high-value utilization of recycled fine aggregates (RFAs) remains limited, leading to inconsistent engineering performance and insufficient durability. Enzyme-induced carbonate precipitation (EICP) represents a promising low-carbon cementation method, yet its deposition uniformity and cementation efficiency are influenced by the pore structure of granular media and associated mass transfer pathways. This study employs a two-stage experimental design to investigate the synergistic effects of particle size distribution characteristics, represented primarily by d₅₀, and fiber addition on EICP-cemented RFA. Phase I (fiber-free; d₅₀ = 0.67–1.14 mm) results indicate that, across the tested gradation schemes, the CaCO₃ content generally decreased from 9.49% to 7.72% as the representative d₅₀ increased, while the dry density changed only slightly (1.637–1.617 g/cm³). However, the unconfined compressive strength (UCS) decreased from 1000 kPa to 541 kPa (45.9% reduction), indicating that strength is primarily governed by the connectivity of the cementation network rather than solely by the degree of densification. In Phase II, glass fiber (GF), polypropylene fiber (PPF), and jute fiber (JF) were incorporated into the ERFA4 gradation scheme selected for fiber modification. All three systems exhibited a unimodal optimum pattern: the peak CaCO₃ contents reached 10.71% (GF 0.5%), 10.11% (PPF 0.7%), and 11.46% (JF 0.7%), corresponding to peak UCS values of 1917, 1874, and 2450 kPa, respectively. Microscopic analysis suggested that fiber bridging coupled with CaCO₃ deposition may contribute to the formation of a “fiber-CaCO₃-particle” stress-transfer network, which is consistent with the observed enhancements in load-bearing capacity, ductility, and post-peak stability. Full article

To address unstable localization and sparse mapping for autonomous vehicles operating in GPS-denied and low-visibility environments, this paper proposes GTS-SLAM, a tightly coupled dense visual SLAM framework integrating Generalized Iterative Closest Point (GICP) and 3D Gaussian Splatting (3DGS). The system is designed for intelligent driving platforms such as underground mining vehicles, inspection robots, and tunnel autonomous navigation systems. The front-end performs covariance-aware point-cloud registration using GICP to achieve robust pose estimation under low texture, dust interference, and dynamic disturbances. The back-end employs probabilistic dense mapping based on 3DGS, combined with scale regularization, scale alignment, and keyframe factor-graph optimization, enabling synchronized optimization of localization and mapping. A Compact-3DGS compression strategy further reduces memory usage while maintaining real-time performance. Experiments on public datasets and real underground-like scenarios demonstrate centimeter-level trajectory accuracy, high-quality dense reconstruction, and real-time rendering. The system provides reliable perception capability for vehicle autonomous navigation, obstacle avoidance, and path planning in confined and weak-light environments. Overall, the proposed framework offers a deployable solution for autonomous driving and mobile robots requiring accurate localization and dense environmental understanding in challenging conditions. Full article

This paper presents a study of low-profile transmitarray antennas using two folded design approaches for microwave energy focusing. One approach realizes profile reduction through reflective phase compensation, whereas the other uses polarization-selective path folding. Prototypes are fabricated and measured, and their aperture performance is evaluated using gain, aperture efficiency, and first-sidelobe level as practical indicators of focusing quality and unwanted radiation outside the main beam. For the reflective phase-compensation design, dual-linear-polarized operation is maintained, and a height reduction of 52% is achieved. The measured broadside gain is reduced by 2.6–2.7 dB for x polarization and 1.6–1.7 dB for y polarization, while the first sidelobe increases by 3.7–6.6 dB for x polarization and by 5.1 dB in the y–z plane for y polarization. For the polarization-selective folded design, the feed-to-aperture distance is reduced from 165 mm to 43.5 mm, giving a compression factor of about 3.8. The measured peak gain is reduced by 3.4 dB, and the first sidelobe increases from −19.9 dB to −13.2 dB in the E-plane and from −16.8 dB to −12.9 dB in the H-plane. The comparison shows that reflective phase compensation is more suitable when dual-linear-polarized operation is required, whereas polarization-selective path folding is more suitable when stronger profile compression is prioritized and single-polarized operation is acceptable. Full article

Hyperspectral imaging provides rich spatial–spectral information but generates huge data volumes, posing significant challenges for storage, transmission, and real-time processing in remote sensing applications. In this study, we propose SpecResNet, a 3D autoencoder-based model for hyperspectral image compression. This framework introduces hybrid residual blocks for preserving representational power and a spectral calibration (SC) block to enhance spectral fidelity. It also uses Squeeze-and-Excitation (SE) blocks for adaptive feature recalibration. Our model obtains different compression operating points by varying model capacity, with bitrate emerging implicitly from the learned latent representations. Experiments on several benchmark datasets show that SpecResNet surpasses the performance of existing frameworks on most datasets in terms of PSNR, MS-SSIM, and SAM, demonstrating its strong potential. Our results suggest that SpecResNet offers a promising trade-off for efficient hyperspectral image compression, with potential for further refinement in complex scenes. Full article

Marine concrete engineering faces severe service environment challenges, including high hydraulic pressure, large stress, and serious penetration. The evaluation of the durability and safety of these structures depends directly on the damage mechanism of concrete materials submitted to high hydraulic pressures. This paper introduced the experimental research on the mechanical properties and the damage mechanism of concrete submitted to high hydraulic pressures. The permeability tests were carried out on concrete specimens under the effect of different hydraulic pressures (1.2 MPa, 2.4 MPa, 3.6 MPa) and durations (10 d, 20 d, 30 d), after which the compressive strength, micro-cracks, and the ultrasonic velocity were obtained and analyzed. The results show that under the effect of sustained high hydraulic pressure, the micro-cracks in concrete increase, the density decreases, and the harmful pores expand, resulting in a degradation in the mechanical properties of concrete. The damage to concrete is more severe at the near end of the hydraulic head than at the far end. The pore water pressure decays gradually with depth inside the concrete and expands inward when the outer layer of concrete is damaged. The conclusions will provide a scientific basis for the safety evaluation of marine concrete engineering. Full article

This study evaluates the mechanical and thermal properties of bricks made from polylactic acid (PLA) and recycled polyethylene terephthalate (rPET). A filament-based 3D printer was used with process parameters specific to PLA, while rPET—also known as recycled plastic—was obtained by grinding and compacting products. Brick samples of various dimensions were manufactured to conduct flexural, compressive, and tensile tests. Several samples were used for each test. On the other hand, a thermal conductivity analysis was performed to determine the internal temperature of dwellings, such as a house or a building. Thermal conductivity influences energy efficiency and the thermal comfort of occupants. The macrostructures observed in the NIKON microscope were examined, where the direction of the fibers and their compaction, which significantly influences thermal conductivity, can be seen. A 53.4% reduction in thermal conductivity was determined for the PLA brick compared to the commercial brick, while the rPET brick showed a 6.4% decrease. The evaluation of the tests carried out on the universal testing machine indicates that the brick made from rPET exhibits a higher maximum load and stress compared to the brick made from PLA in all tests. These results suggest that both the manufacturing process and the composition of the material have a significant impact on the mechanical and thermal properties of plastic bricks. In the flexural test, the recycled plastic brick withstood a maximum stress of 16 MPa and a maximum load of 5784 N. Similarly, in the compression test, the recycled plastic brick withstood a maximum load of 9471 N and a maximum stress of 5.83 MPa. During the tensile test, the rPET brick demonstrated a maximum load of 9203.92 N and a maximum stress of 5.64 MPa. These results show that bricks made from recycled plastic have better mechanical properties compared to polylactic acid bricks in the tests carried out and can therefore be considered for use in the construction industry. Full article

Introduction: The retropharyngeal carotid artery (RCA) is a rare anatomical variant where the carotid artery resides in the retropharyngeal space. The co-occurrence of RCA and significant atherosclerotic stenosis of the carotid bifurcation is even rarer. Recognizing this anatomy is crucial because of the increased risk of adverse events during procedures such as intubation or oropharyngeal surgery. Furthermore, differentiating between the fixed and dynamic forms is essential for guiding appropriate diagnostic and therapeutic strategies. A scoping review was undertaken, and two cases of RCA and significant internal carotid artery stenosis requiring a surgical approach were presented. Materials and Methods: EMBASE and OVID were systematically searched for studies reporting data on RCA and significant internal carotid artery stenosis. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) was followed, and we presented two case reports of RCA and significant internal carotid artery stenosis requiring surgical treatment, treated at the Division of Vascular Surgery, IRCCS MultiMedica, Sesto San Giovanni, Milan, Italy. Results and Discussion: Among the 22 papers identified by the scoping review, 6 case reports were ultimately included in the analysis, supplemented by our two cases. The review and the added cases highlight significant heterogeneity in the clinical presentation and management of RCA with stenosis. Therapeutic options include carotid endarterectomy (CEA), transfemoral carotid artery stenting (TF-CAS), and transcarotid artery revascularization (TCAR). Also, the diagnostic with dynamic 3D-CT angiography during swallowing would be important in some symptomatic cases to document mechanical compression by the hyoid bone or thyroid cartilage (dynamic RCA), which standard static imaging failed to detect. Conclusions: Due to the rarity of the condition, no high-level evidence (RCTs) exists. Treatment decisions are based on the qualitative assessment of anatomical risk and isolated case reports. Standard interventions (CEA and TF-CAS) are generally considered high-risk. The final management choice must be individualized based on technical feasibility, neurological risk, and the determination of whether the pathology is fixed or dynamically compressive. Full article

Current 360-degree video streaming systems consider viewport prediction, adaptive bitrate allocation, tile selection, and quality-of-experience (QoE) estimation as independent activities, yielding fragmented pipelines that do not scale well across content type and network conditions and do not scale well to individual users. We propose ImmerseFM-3D, a foundation model that jointly solves all four sub-tasks through a single shared representation. Seven input modalities, namely video frames, network traces, head-motion trajectories, ambisonics audio, depth maps, eye-tracking signals, and CLIP scene semantics, are fused by four-layer cross-modal attention and compressed into a 256-dimensional bottleneck latent via a variational information bottleneck. Four task-specific decoders operate on this shared latent simultaneously. A model-agnostic meta-learning adapter augmented with episodic memory and a hypernetwork personalizes the model from as little as 1 s of user interaction data. An extended branch supports six-degrees-of-freedom volumetric content through spherical harmonic viewport decoding and depth-aware tile importance weighting. Trained and evaluated on the IMMERSE-1M combined dataset (1000 h of 360° and volumetric video, 524 users, and over 50,000 mean opinion scores), ImmerseFM-3D reduces the mean angular viewport error by 34%, lowers the bandwidth violation rate from 8.3% to 3.1%, and achieves a QoE Pearson correlation of 0.891. The personalization adapter reaches 90% of peak performance in 22 s, while zero-shot cross-format transfer attains 72% of full in-domain accuracy. Full article

Building 3D printing technology exhibits remarkable construction advantages, with solid waste-based 3D printing slurry emerging as a research hotspot in the field. Phosphogypsum is compatible with diverse solid wastes for the fabrication of geopolymer, whereas its feasibility as a 3D printing material merits further investigation. In this study, calcium carbide slag (CS), ground granulated blast-furnace slag (GGBS), recycled concrete powder (RCP), and phosphogypsum (PG) underwent co-activation. The mix proportion received optimization via response surface methodology (RSM), and printability assessment proceeded based on the optimized proportion. Key conclusions include the following: PG exerts a role in optimizing the internal structure within the geopolymer matrix. The 28-day compressive strength of the composite geopolymer exceeds 25 MPa. Application as a 3D printing material facilitates enhancement of slurry stability in the later stage. Excessive PG addition elevates the shear stress and viscosity of the 3D printing paste, shortens the paste open time, and impedes paste extrusion and molding. Based on a comprehensive analysis of printability and the performance of printed specimens, the optimal mix proportion of the phosphogypsum-based geopolymer 3D printing paste was determined as follows: CS: 22.5%; GGBS: 45%; RCP: 22.5%; PG: 10%; W/b: 0.4. Full article