Search Results (203)

Facing the challenges in field monitoring of the mechanical response of geogrids in asphalt pavements, this study integrated two types of Fiber Bragg Grating (FBG) sensors, unarmored and armored, into geogrids using the pillar-stitching technique on industrial warp-knitting production lines. The integrated FBG-geogrid systems were comprehensively evaluated in both wound and flattened configurations, enabling the selection of a sensor type suitable for industrial production. After precise strain calibration, a full-scale field damage test was performed during the construction of the Qu-Gang Expressway in Hebei Province, China. The results demonstrate that the helical steel armor layer significantly enhances the mechanical durability of the FBG sensor. Specifically, the armored sensor maintained stable optical transmission over its entire 60-m length, with an average performance retention rate of 98.86% in the flattened state. Moreover, a strong linear correlation was established between the wavelength shift of the armored FBG sensor and the tensile strain of the geogrids. In contrast, the unarmored FBG sensor underwent irreversible shear deformation during production and contained at least two breakpoints. Additionally, a protection scheme employing fiberglass-reinforced silicone rubber on the hot side and standard silicone rubber on the cold side effectively shielded the sensors from high-temperature and compaction loads during asphalt paving. Consequently, the proposed FBG-geogrid integration method and the corresponding field protection strategy provide technical support for the real-time monitoring of geogrid performance in asphalt pavements and have significant engineering value. Full article

Industrial pneumatic systems are central to automated production but often exhibit low efficiency and high energy costs due to pressure drops, leaks, and related issues. Air leaks increase operational expenses and degrade actuator performance. This study introduces a reliable classification-based approach for subsystem-level localization of single leaks. Each operating cycle is mapped to one of four actionable states using a Dynamic Time Warping (DTW) algorithm applied to time-series data from a single inlet flowmeter, distributor switching signals, and actuator end-position sensors. The method distinguishes whether a leak occurs in the supply line, actuator circuit, or dynamically during the extension stroke. Unlike conventional metrics such as Euclidean, Canberra, and Pearson distances, DTW does not require equal-length signals and compensates for leak-induced temporal shifts, achieving complete class separation. Experimental validation included 200 cycles: 50 under normal conditions and 150 across three fault states (inlet leak, actuator leak, and dynamic leak), sampled at 10 Hz. DTW distances showed no overlap between class distributions. A Leave-One-Out 1-NN classifier achieved 100% accuracy across all classes. The approach is low-cost, automated, and suitable for real-time implementation with minimal sensors, supporting integration into machine learning frameworks and enhancing energy efficiency in pneumatic systems. Full article

We investigate Ricci–Bourguignon solitons on mixed doubly sequential warped product manifolds. Necessary and sufficient conditions for the existence of such solitons are established, and their implications for Einstein manifolds are analyzed. This work extends previous results on warped product manifolds to the more complex case of mixed doubly sequential warped products. We derive explicit formulas for Ricci tensor components, establish conditions for Einstein metrics, and study gradient solitons and conformal vector fields. Our classification theorems reveal fundamental separability constraints on the warping functions. Applications to cosmological models and black hole solutions demonstrate the physical relevance of these results. Full article

This study evaluates the effect of loading size on the longitudinal warping of beech wood containing reaction wood. Reaction wood in hardwood species has properties that negatively affect not only the usability of wood products but also the processing of the wood in which it is found. To investigate these effects, steam pressure treatment and three levels of mechanical loading (700, 2000, 4000 kg·m⁻²) were used, along with the effect of the proportion of reaction wood. Steam pressure treatment generally caused greater warping, particularly in unloaded specimens, due to increased release of internal growth stresses. Mechanical loading effectively reduced deformation, with the most pronounced effects observed at 700 and 2000 kg·m⁻²; further increases in loading did not provide any significant additional benefits. Although the proportion of reaction wood ranged from 14% to 56%, there was no obvious statistical correlation with deformation, suggesting that the distribution and degree of development of reaction wood have a greater impact than its total content. Overall, hydrothermal treatment induces the release of internal stress, leading to warping, while moderate mechanical loading can successfully limit warping. Understanding these interactions is key to processing beech wood with reaction wood and to improving the quality of finished products. Full article

We investigate gradient Einstein solitons admitting closed conformal vector fields. Under constant scalar curvature, we establish rigidity results showing that complete solitons with non-parallel closed conformal vector fields are isometric to Euclidean space. In the non-compact case, we prove that solitons with homothetic closed conformal vector fields are locally conformally flat in dimension four and possess a harmonic Weyl tensor in higher dimensions. Furthermore, we obtain a classification result, showing that such solitons admit a warped product structure with a one-dimensional base and space form fibers. Full article

Nowadays, synthetic textiles, widely used on the market and largely composed of polyester (polyethylene terephthalate, PET), release microplastic fiber fragments (MPFFs) into the environment, inducing repercussions on ecosystems and health. Reducing these emissions by understanding manufacturing’s influence on MPFF release represents an important challenge for sustainable textile manufacturing and eco-design. This study aims to identify key weaving process factors influencing MPFF release during the first wash, which ends up in wastewater. Employing a Taguchi design of experiments, 18 fabrics were produced on industrial machines from polyester filaments, with different warp and weft densities, weaving patterns, and production speeds. Following identical black dyeing and finishing treatments, the range of the average quantity of MPFF released per fabric varies from 221 mg/kg to 753 mg/kg with an overall mean value of 451 mg/kg across all trials. Among the investigated parameters, warp yarn density and weaving pattern emerged as the most influential factors, accounting for the largest variations in MPFF release. Increasing warp density from 40 to 60 yarns/cm resulted in a substantial increase in MPFF emission, while the 3/1 sateen weave exhibited significantly lower MPFF release compared to plain and ottoman weaves. In contrast, weft density and weft insertion speed showed limited influence relative to experimental variability. No clear correlation was observed between the number of filaments in the weft yarn and MPFF release. These results show that the higher the surface mass, the cover factor, and the drape coefficient, the higher the release of MPFFs. This study shows that it is possible to limit the amount of microfibers generated by textiles by controlling the design and production of fabrics. The results support the integration of microplastic mitigation criteria into sustainable textile engineering and industrial eco-design frameworks. Nevertheless, the complexity of the release mechanisms and potential interactions between factors highlights the importance of conducting further research to determine the specific fabric characteristics that influence MPFF release. Full article

The increasing share of photovoltaic (PV) generation in building energy systems highlights the importance of understanding not only the magnitude but also the temporal structure of energy mismatch between PV production and building demand. This study proposes a Dynamic Time Warping (DTW)-based framework for the analysis of daily temporal mismatch patterns in a building-integrated photovoltaic system using high-resolution measurement data. Daily temporal signatures are constructed from normalized PV generation and building load profiles, allowing the analysis to focus exclusively on temporal deformation rather than absolute energy values. Pairwise DTW distances are used to construct a distance matrix that captures similarities between daily mismatch structures over an entire month. The resulting DTW distance matrix enables not only pairwise comparison of daily mismatch patterns, but also the identification of representative, transitional, and extreme days through ranking and hierarchical organization of temporal signatures. Hierarchical clustering with average linkage reveals distinct families of days characterized by similar types of temporal deformation, while a ranking based on average DTW distance provides a compact diagnostic summary of monthly variability. The findings demonstrate that PV–building energy matching is inherently time-structured, forming recurrent temporal families of days that cannot be identified using aggregate energy metrics alone. The proposed framework provides a robust diagnostic layer for time-aware energy analysis and supports the development of advanced control and management strategies that explicitly address temporal mismatch in building-integrated photovoltaic systems. Full article

Nishijin weaving in Kyoto developed as a luxury textile for kimono, yet sustaining the district requires expansion toward contemporary apparel and markets. Within a silk-centred culture and quality regime, polyester has been adopted as a versatile option, and its use has increased, especially for kimono-related products, partly because its filament form can substitute for silk and fit existing processes. From this trajectory, we explore a craft–code–craft pathway by integrating a biodegradable polyester grade into Nishijin’s code-based Jacquard production (CGS). Through practice-based research, we trace how design intent is encoded (Houdini → CGS → Jacquard) and how shop-floor constraints reconfigure design (Jacquard → CGS → Houdini), revealing institutional constraints that shape which materials become usable. We report three case studies: (A) 3D woven structures informed by pleat parameterisation, (B) a zero-waste garment using a 25 cm repeat logic, and (C) a fashion show that makes translation processes legible to the public in an exhibition context. While biodegradable polyester can fit existing infrastructure, apparel-grade warp use remains under development due to warping and warp-joining requirements; yarn specifications and design parameters are being revised. By foregrounding translation across tools, roles, and standards, the study proposes pathways for material transition and circularity within a craft system. Full article

This paper investigates the dynamic interaction between photovoltaic (PV) generation and building electricity demand with a focus on temporal alignment. A combined framework integrating state-based clustering and Dynamic Time Warping (DTW) is proposed to jointly analyze instantaneous operating states and time-dependent profile similarity. High-resolution (15 min) data from a 50 kWp building-integrated PV system supplying an administrative university building were analyzed for March 2025. Unsupervised k-means clustering was applied in the production–consumption state space to identify typical operating regimes, while DTW was used to compare daily PV generation and load profiles accounting for temporal shifts. The results show that days classified as similar based on instantaneous energy states may exhibit substantially different temporal structures that remain invisible in state-based analyses. To assess the practical relevance of temporal similarity, DTW distances were related to daily energy performance indicators. No significant relationship was observed between DTW distance and the self-consumption ratio under high-load conditions; however, a strong and statistically significant correlation (Pearson r = −0.60, p < 0.001; Spearman ρ = −0.53, p < 0.01) was found between DTW distance and a temporal overlap index quantifying the fraction of building load occurring during the PV-active period. The authors demonstrate that the applied DTW algorithm identifies temporal mismatches that have a measurable impact on energy metrics directly linked to load–generation coincidence. These findings confirm that temporal alignment constitutes an independent and operationally meaningful dimension of PV–building energy interaction that cannot be fully captured by state-based or energy-aggregated indicators alone. Full article

This paper studies the conformal geometry of complete gradient Schouten solitons (GSSs) admitting closed conformal vector fields (CVFs). We establish rigidity and characterization results for nonparallel, homothetic closed CVFs under the assumption that the gradient of the scalar curvature is parallel to the CVF. It is shown that such manifolds are isometric to Euclidean space. Moreover, complete noncompact GSSs with constant scalar curvature are locally conformally flat in dimension four and have harmonic Weyl curvature in higher dimensions. Finally, we prove that these manifolds are totally umbilical if and only if their scalar curvature is constant, and they form warped products with space forms. Full article

The growing threat posed by climate change and extreme weather events necessitates the adoption of advanced solutions for crop protection, such as agrotextile nets. The use of anti-rain (AR) and anti-insect (AI) nets is essential to safeguard production, but their effectiveness varies significantly. AR nets offer rain protection but can compromise ventilation, while AI nets ensure a better microclimate but offer poor resistance to precipitation. Given the lack of a standardized index, this study aims to use the rainwater permeability index (Φ_rw) to provide an objective parameter for evaluating and comparing the performance of different agrotextiles. Laboratory tests were conducted on eight different nets (three AR and five AI) using a rainfall simulator. The Φ_rw index, defined as the ratio between the mass of water passing through the net and the total mass of water applied, was evaluated as a function of rainfall intensity (39, 80, and 170 mm/h), net inclination (10°, 20°, and 30°), and the orientation of the warp relative to the slope. The results confirmed that AR nets are most suitable in protecting crops from extreme rainfall, because it becomes clear that AI nets are much more permeable than AR nets. In this sense, the plots show that AI nets usually have a higher permeability than AR nets, between 15% and 25%, depending on rainfall intensity and net inclination. In fact, the AR1 net showed the best performance, with Φ_rw values stabilizing between 40% and 50% under the most common installation conditions. Conversely, AI nets generally exceed 60% permeability, with the AI1 net reaching Φ_rw above 90%, confirming their inadequacy for rain protection alone. In general, AR nets show Φ_rw between 33% and 92%, while Φ_rw for AI nets ranges from 45% and 98%. The research allowed for the comparison of eight agricultural nets with different characteristics and the identification of those that perform best in terms of protection against three different levels of rainfall intensity. The introduction of the Φ_rw index constitutes a significant contribution, providing a quantifiable standard for the selection of agrotextiles in terms of protection from rainfall, regardless of manufacturers’ claims. The data obtained underscore the need to develop future hybrid and multifunctional nets capable of balancing the low water permeability of AR nets with the high ventilation and insect protection of AI nets, thereby ensuring an optimal microclimate and comprehensive crop protection. Full article

Multi-laser powder bed fusion is an emerging additive manufacturing technology that enables the production of high-performance components with intricate geometries and large aspect ratios. These tall, slender structures are highly susceptible to steep thermal gradients and residual stress, leading to deformation that compromises dimensional accuracy and structural integrity. This study investigates how geometric compensation, support structure design, and part scaling influence thermal deformation in Inconel 718 components fabricated via multi-laser powder bed fusion. Using pre-compensation, iterative support refinements, and scaled experimental builds, the deformation response across multiple geometries and print strategies is evaluated. Both compensated and original designs are printed on a commercial system equipped with three simultaneously operating lasers. Results show that printing high-angle surfaces without support structures is infeasible, as thermally induced warping and delamination lead to catastrophic failures. Conical support structures spanning critical regions reduce deformation by more than 50% compared to unsupported builds. Reduced-scale parts, however, do not reliably replicate full-scale deformation behavior due to altered boundary conditions and thermal pathways. These findings highlight the need for integrated design-for-AM workflows where compensation, support design, and scale effects are addressed jointly. The study demonstrates that deformation mechanisms do not scale linearly, emphasizing the limitations of small-scale proxies and the necessity of full-scale validation when developing reliable, deformation-aware design strategies for multi-laser powder bed fusion. Full article

In this paper, we investigate contact skew CR-warped product submanifolds of locally conformal almost cosymplectic manifolds, a framework that simultaneously generalizes warped product pseudo-slant, semi-slant, and contact CR-submanifolds. We first establish a necessary and sufficient characterization theorem showing that a proper contact skew CR-submanifold with integrable slant distribution admits a local warped product structure if and only if certain shape operator conditions involving the slant angle and the warping function are satisfied. Subsequently, we derive sharp geometric inequalities for the squared norm of the second fundamental form in terms of the warping function, the slant angle, and the conformal factor of the ambient manifold. The equality cases are completely characterized and lead to strong rigidity results, namely that the base manifold is totally geodesic while the slant fiber is totally umbilical in the ambient space. Several applications are presented, showing that our results recover and extend a number of known inequalities and classification theorems for warped product submanifolds in cosymplectic, Kenmotsu, and Sasakian geometries as special cases. Full article

The increasing environmental impact of the textile industry has led to the development of sustainable production methods. One of the effective approaches is the use of recycled fibers, which helps to save resources, reduce carbon emissions, and support the circular economy. This study investigates the feasibility of producing durable upholstery fabrics incorporating recycled polypropylene (r-PP) and virgin polypropylene (v-PP). Filament yarns with varying r-PP/v-PP blend ratios, produced by the melt spinning process, were used as weft yarns, while commercially available virgin polyester filament yarns were employed in the warp direction for all fabric samples. Performance tests in accordance with the standards were applied to the fabrics and the results were also evaluated statistically. The results show that acceptable performance is achieved in some mechanical properties if similar blend ratios and production parameters are used. In the study, an optimization model was developed to maximize the weft breaking strength using the equations obtained from the regression analyses. With the help of the mathematical model created, the values of other physical and performance properties of the fabric depending on the maximum breaking strength value could be estimated without the need for trial production. The model was solved using Lingo 18.0 optimization software. The solution of the model revealed that the optimum weft yarn blend ratio is 10/90 r-PP/v-PP, and the maximum weft breaking strength value is 562.45 N. Full article

Sizing is a critical operation in woven fabric production, as it enhances weaving efficiency by improving warp yarn performance. Conventional sizing agents include maize starch, polyvinyl alcohol (PVA), and commercial carboxymethyl cellulose (CMC). In this study, a low-cost and biodegradable carboxymethyl cellulose derived from wheat straw (CMC_ws) was investigated as an alternative sizing agent for cotton open-end yarns with a count of Nm 12.2. The high degree of substitution (DS = 1.23) of CMC_ws indicates extensive carboxymethylation, which enhances the polymer’s hydrophilicity and solubility in water. This, in turn, contributes to a higher apparent viscosity (η = 903.03 cP at 300 s⁻¹), reflecting stronger molecular chain interactions and better film-forming ability. CMC_ws was applied using a high-pressure squeezing technique, and its effect on yarn performance was evaluated in terms of tensile properties, film characteristics, and yarn surface morphology. The results showed that CMC_ws provided a tenacity gain of 28.57%, a hairiness reduction of 54.34%, and an abrasion resistance gain of 37.14%. These values fall within acceptable industrial ranges and are comparable to those obtained using conventional sizing agents. Furthermore, the optimized CMC_ws formulation, containing plasticizer and lubricant additives, exhibited good desizing efficiency, with effective removal achieved in hot water. The findings indicate that wheat-straw-derived CMC_ws is a viable, sustainable alternative to traditional sizing agents for woven fabric production. Full article