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A super-sensitivity incoherent optical method with time-delay embedding for pixel-limited dynamic displacement measurements
No full textThe sensitivity of incoherent optical methods using digital cameras (e.g., photogrammetry with optical flows and digital image correlation) for full-field displacement measurements, defined as the minimum measurable displacement, is inherently limited by the bit depth B of the digital camera due to the quantization error, with a single-pixel theoretical sensitivity limit as δp=1/(2B−1) [pixel]; however, it is not achievable due to the existence of noise in practice. Recent research has leveraged the random noise and the spatial-pixel-averaging with dithering to exceed such a sensitivity limit, achieving super-sensitivity displacement measurements. In particular, the derived mathematical model indicates that the achieved super sensitivity is inversely proportional to the square root of the number of the effective pixel (those record actual intensity changes due to the object displacement), i.e., a larger effective pixel number for averaging is advantageous for super sensitivity. However, it may not be realized practically in common situations where the number of effective spatial pixels available for averaging is limited. To address the limitation of limited pixels available for super-sensitivity measurements, in this study we incorporate the time-delay embedding into the pixel-limited dynamic displacement measurements to achieve super sensitivity. The key innovation is to leverage abundant temporal samplings to compensate for the pixel-limited spatial-dimensional samplings. Specifically, we leverage the time-delay embedding of temporal samplings to construct pseudo-phase-space samplings, allowing an application of an SVD-based adaptive averaging over the pseudo-phase space with natural dithering to achieve super-sensitivity displacement estimations with limited pixels. For validations, the most challenging pixel-limited scenario, i.e., only one-effective-pixel measurement case, is focused on in this study. Numerical simulations, including theoretical and optical flow simulations, and laboratory experiments on the incoherent optical measurement using a representative 8-bit video camera of the vibration of a bench-scale three-story building structure and a cantilever beam structure are conducted, respectively. The results indicate that the developed method is able to achieve super-sensitivity measurement of dynamic displacements with limited effective pixels, especially approaching the coherent laser displacement sensor (LDS) performance with increasing number of pseudo-phase-space dimensions. Furthermore, a mathematical model is derived for the achievable super-sensitivity (minimum measurable displacement) as δp∗∝[σn(1/ND+1/NL)]δp, where σn is the noise level, ND and NL the number of dimensions of the constructed pseudo-phase space and the number of temporal samplings in the pseudo-phase space for averaging, respectively, and δp=1/(2B−1) [pixel] the nominal single-pixel sensitivity limit. We also discuss the current limitations of the developed method and the required further work
Mapping the distribution and condition of mountain peatlands in Colombia for sustainable ecosystem management
No full textHigh mountain peatlands in Colombia play a crucial role in water regulation, store significant carbon, and yet remain poorly studied and threatened. The lack of a comprehensive national peatland map hinders effective management. Our objectives were to create a national mountain peatland map for Colombia, assess peatland distribution, quantify degraded pasture peatlands, and evaluate soil carbon percentages and bulk density in the top 40cm of mountain peatlands soils. We developed and compared three national-scale maps using field validation, Sentinel-2 imagery, SAR data, and topographic variables as inputs to a Random Forest classifier, each reflecting a different grouping of the study area. The Subregional map classifies four smaller subregions individually and merges them, the Regional groups two larger regions, and the National classifies the entire study area. Mapping 4.8 million hectares, we found peatlands occupy approximately 225,000 to 250,000 ha. About 13–15% are pasture peatlands, even within protected areas, 7–8% have been disturbed. Soil analyses up to 40cm show consistently high carbon percentage in undisturbed peatlands, whereas pasture peatlands exhibit lower carbon and higher bulk density, revealing detrimental effects caused by drainage and livestock. These findings underscore the urgent need for targeted conservation and restoration to reduce greenhouse gas emissions, protect water resources, and strengthen climate mitigation strategies. Future research should refine peatland depth estimates to enhance the accuracy of peatland carbon stock assessments, leverage all three maps to improve training data in areas with substantial discrepancies, and use emerging technologies to better detect unaccounted peatland degradation
Global Forests
No full textForests across the world are changing rapidly and, by most measures, they are in a great deal of trouble. Many people see forests as little more than attractive backdrops to the real stuff of human history, but our human stories are intimately interconnected with forests. This chapter explores some of the often invisible links between forests and human histories. Tropical forests were never leveled by glaciation, so they continued developing as communities, becoming more complex and diverse over the millennia. Within European and Mediterranean forests, similar transformations followed the expansion of agriculture and trade. The links between people and forests were often invisible to the cadre of professional foresters who followed colonial powers around the world. Globally, since the 1950s, tropical rain forest has been reduced by over 60 percent. In some regions, the loss has been even greater. Even with continued protections, efforts to sustain tropical forests could be severely undermined by climate change
Modeling and Analysis of Wind Turbine Wake Vortex Evolution Due to Time-Constant Spatial Variations in Atmospheric Flow
Full text linkModern utility-scale wind turbines are evolving toward larger, lighter, and more flexible designs to meet the growing demand for renewable energy while minimizing logistical costs. However, these advancements in lightweight design result in heightened aeroelastic sensitivity, leading to complex interactions which affect the rotor’s capacity to withstand aerodynamic loading and the cascading effects that manifest in the wake’s vortex-structure evolution under variable atmospheric conditions. In this paper, we analyze the influence of stream-wise fluctuating atmospheric flow conditions on wind turbines with large, flexible rotors through simulations of the National Rotor Testbed (NRT) turbine, located at Sandia National Labs’ Scaled Wind Farm Technology (SWiFT) facility in Lubbock, Texas. The Common Ordinary Differential Equation Framework (CODEF) modeling suite is used to simulate wind turbine aeroelastic oscillatory behavior and wind farm vortex–wake interactions for a range of conditions with spatially variant atmospheric flow. CODEF solutions for turbine operation in wind conditions featuring only one parameter fluctuation are compared to wind conditions with several wind parameter variations in combination. By isolating individual inflow variations and comparing them to multi-parameter scenarios, we determine the contributions of each atmospheric factor to rotor dynamics, wake evolution, and downstream wind farm interactions. The purpose of this paper is to analyze the effects of spatial variations in atmospheric flow on the topological evolution of wind turbine vortex wakes, which constitutes a gap in the current understanding of wind turbine wake dynamics. The insights gained from this study are particularly valuable for the development of wind farm control strategies aimed at mitigating the adverse effects of wake interactions, enhancing energy capture, and improving the overall stability of wind farm operations. With these insights, we aim to contribute to the development of modeling and simulation tools to optimize utility-scale wind power plants operating in diverse atmospheric environments
The Neuromarketing: Bridging Neuroscience and Marketing for Enhanced Consumer Engagement
Full text linkThis review paper examines the influence of neuromarketing on consumer behavior research, emphasizing its origins, methodologies, impacts, and implications for customer engagement. This paper conducts a thorough narrative literature review on neuromarketing, analyzing the application of diverse neuroscientific techniques, including functional magnetic resonance imaging (fMRI), electroencephalography (EEG), positron emission tomography (PET), magnetoencephalography (MEG), and facial coding/eye tracking, to assess cerebral responses and forecast consumer behavior. Recent scholarly investigations underscore how neuromarketing utilizes contemporary breakthroughs to transform consumer behavior research by offering enhanced insights into cognition and emotion. These sophisticated tools have contested conventional study methodologies, facilitating a more comprehensive comprehension of the interaction between marketing stimuli and the brain. The theoretical and practical aspects of the findings are that advanced neuroimaging techniques like fMRI, EEG, and eye-tracking have revealed the complex interactions between emotions, attention, and memory that traditional methods and neuromarketing transform marketing by giving marketers new tools and approaches to boost results. This review synthesizes previous research on the topic, highlighting the necessity for equilibrium between scientific advancement and ethical accountability in neuromarketing, thereby benefiting both academic and commercial sectors
Wavelet-based time-domain double-fed induction generator differential protection
No full textDouble-fed induction generators (DFIGs) must remain connected to the grid for a specific time during faults on the grid but must be immediately disconnected during short circuits inside of their protection zone, such as faults in the stator or rotor windings, to reduce potential damage risks. Currently, there is no reliable solution to discern whether a fault is external or internal to the DFIG protection zone. The differential protection appears suitable for this purpose, yet few studies have applied this protection to DFIGs. Additionally, there is insufficient evidence regarding the effectiveness of differential protection schemes in detecting faults in DFIG. This paper introduces a new algorithm for protecting the DFIG in the time domain using wavelets. The method utilizes high- and low-frequency components of the stator and rotor currents on the d- and q-axis to offer fast and dependable protection for the DFIG. The proposed approach was compared to existing differential protection regarding success rate and average response time across various events, including faults on the grid and turn-to-turn faults on the stator and rotor. The results indicate that the proposed protection outperforms the existing one and is the fastest in detecting turn-to-turn faults on the stator and rotor windings
Performance evaluation of glass powder as a partial precursor in alkali-activated slag (AAS) binder and recycled glass and steel fibers in AAS mortar
No full textTo reduce environmental impacts such as landfill waste from glass and tire fibers and to develop sustainable, low-carbon construction materials, this study explores the use of waste glass powder as a precursor in alkali-activated slag (AAS) binders and the recycling of glass particles and tire steel fibers in AAS mortar. The effects of glass powder (GP) as a precursor replacement were compared with those of a control and class F fly ash (FA)-modified AAS binder. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) revealed that GP and FA promote geopolymer formation due to the dissolution of quartz. Nitrogen absorption tests indicated a slight increase in geopolymerization phases with GP replacement, consistent with SEM results and the compressive strength of the AAS binder. In the binder tests, the control AAS binder exhibited the highest compressive strength, while GP-modified samples outperformed FA replacements. GP-modified binders also extended setting times and reduced alkali leaching by over 30% compared to the control. In mortar systems, replacing natural sand with recycled glass sand (GS) increased 28-day compressive strength by approximately 5.1%, while adding recycled tire steel fiber (RTSF) improved compressive strength by up to 9.1%, splitting tensile strength by 30%, and flexural strength by 2.5% compared to non-reinforced mixes. Sustainability analysis indicated that using GP as a partial precursor in AAS binders can reduce CO₂ emissions by nearly 5% compared to normal AAS samples. This study uniquely compares GP and FA as partial precursors and introduces an integrated approach by simultaneously incorporating recycled glass sand and RTSF in mortars, thereby enhancing the mechanical properties, durability, and sustainability of AAS materials
High-heat transfer lithium-ion batteries: A new era in battery thermal management
Full text linkDespite advances in lithium-ion battery technology, critical challenges remain that must be addressed to accelerate electric vehicle (EV) adoption and global energy transformation. Significantly improved battery thermal management (BTM) is key to overcoming these challenges. BTM approaches focus on increasing heat transfer coefficients via air, liquid, or refrigerant cooling, but less attention is given to reducing the battery\u27s thermal resistance, a major bottleneck for heat transfer. This work introduces a novel approach to reduce battery thermal resistance by integrating in-plane heat transfer with optimized cell geometry, minimized thermal resistances, and reduced interfacial resistances, representing a departure from previous methods. The standard prismatic can cell incorporating this technology is referred to as the high heat transfer (HHT) battery. An equivalent resistance battery thermal model is developed for speed and accuracy, validated against experimental data in the literature, demonstrating strong correlation and ensuring reliable predictions for real-world performance. Thermal performance metrics of the conventional and HHT batteries are compared using a parametric study with air, liquid, and refrigerant boundary conditions across a range of aspect ratios. The HHT battery shows a heat removal rate up to 20 times higher than a conventional battery. These findings suggest that HHT technology could be transformative for EV battery performance, enabling fast charging, mitigating thermal runaway, extending battery life, reducing cold-weather power loss, increasing reliability, lowering costs, and enabling higher energy density, all critical for EV adoption and energy transformation. Future work will focus on prototyping and real-world testing to refine these findings for commercial-scale applications
Corrigendum to “Reconstructing the geological and geomorphological history of Morella Crater, Mars” [Geomorphology 479 (2025) 109740] (Geomorphology (2025) 479, (S0169555X25001503), (10.1016/j.geomorph.2025.109740))
No full textThe authors regret that the caption for Figure 9 is incorrectly mentioned in the manuscript. The correct caption is given below: Fig. 9 Schematic sketches showing the evolutionary history of Morella: (a) Morella in its initial form with a characteristic CEA and breccia lens (b) Over time, the crater becomes infilled (c) Formation of the collapsed structure, Ganges Cavus, which was formed after the rupture in the cryosphere (d) Water begins to emerge from Ganges Cavus (e) Eventual pooling of the crater (f) Final crater breach in the eastern rim, giving rise to the formation of outflow channels (g) Subsequent changes in Morella Plains and Elaver Vallis.The authors would like to apologise for any inconvenience caused
Performance characterization and mechanistic study of dry process WR/SBS composite modified asphalt mixture
Full text linkThe dry process modification is characterized by simplicity, flexibility, low energy consumption, and low pollution, making it an ideal choice in pavement repair engineering. This study aims to optimize the use of waste rubber powder and SBS modifiers in dry process composite modification by preparing dry process WR/SBS composite modified particles (WR/SBS CMP) using a twin-screw extruder. The optimum mixing content of modified particles was determined through comparative analysis of pavement performance of dry process WR/SBS composite modified, wet-process SBS-modified, and matrix asphalt mixtures. The rheological properties and modification mechanism of the asphalt binder extracted from these mixtures were tested and analyzed. The results indicate that when the content of dry process WR/SBS CMP is 2.3 % of the aggregate weight in the mixture, the comprehensive pavement performance of the dry process composite-modified asphalt mixture is optimal. Melt extrusion granulation at high temperatures, along with the addition of additives such as naphthenic and aromatic oils, promoted the degradation and refinement of the rubber powder and SBS, improving their compatibility and dispersion within the asphalt binder. The modified particles uniformly interact with the asphalt binder, increasing the proportion of elastic components, reducing stress sensitivity, and enhancing performance at both high and low temperatures, and fatigue resistance. Fourier Transform Infrared Spectroscopy (FTIR) confirmed that the modification mechanism was a physical modification. This research promotes the broad application of waste rubber powder and dry process modification in asphalt mixtures, offering significant economic and social benefits