Search Results (9)

The prediction of ground deformation during ultra-shallow-buried pilot tunnel construction is critical for urban rail transit projects in complex geological settings, yet existing cross-section models often lack accuracy. This study proposes an enhanced non-uniform convergence model based on stochastic medium theory, which decomposes surface settlement into uniform soil shrinkage and non-uniform initial support deformation. A computational formula for horseshoe-shaped sections is derived and validated through field data from Kunming Rail Transit Phase I, demonstrating a 59% improvement in maximum settlement prediction accuracy (reducing error from 7.5 mm to 3.1 mm) compared to traditional methods. Its application to Beijing Metro Line 13 reveals two distinct deformation patterns: significant ground heave occurs at 2.5 times the tunnel width from the centerline, while maximum settlement concentrates above the excavation center and diminishes radially. To mitigate heave, early strengthening of the secondary lining is recommended to control initial horizontal deformation. These findings enhance prediction reliability and provide actionable insights for deformation control in similar urban tunneling projects, particularly under ultra-shallow burial conditions. Full article

Background: Black and white women describe their chronic vulvar pain (CVVP) symptoms differently, indicating a patient–provider communication deficit. This may contribute to the diagnostic delay commonly reported by patients with CVVP and/or pelvic pain. Methods: A pilot study demonstrated CVVP terminology differences between women of color and white women. The present study (N = 488) includes a sample of predominantly cisgender women who identified their race/ethnicity as Black, Hispanic/Latinx, Native American/American Indian, and/or Asian. Participants reported how they describe their CVVP, their healthcare experiences, and characteristics of their diagnostic journey. Results: Descriptions of CVVP were not uniform. Instead, there was great variability in how women described their pain across racial/ethnic identities and pain contexts (e.g., sexual activity, menstrual product use, and pelvic exam). Some pain experiences and descriptors were associated with healthcare outcomes related to diagnostic delay. Conclusions: This study sheds light on the pain communication experiences of women of color with CVVP, an understudied population within the broader CVVP literature. By resisting white and non-white comparative methodologies, this study demonstrates the applicability of intersectionality principles to the study of CVVP and contributes to the existing literature regarding pain communication, race, and ethnicity. Full article

This pilot study explores the potential of near-infrared spectroscopy (NIRS) for predicting sunflower seed protein content, focusing on both crushed and husked samples to address agricultural sustainability concerns. Sunflower seeds are renowned for their richness in both oil and protein content. The important role of sunflower seeds in the food and feed industries underscores the importance of using precise analytical tools to determine their composition. In essence, the nature of the hull of sunflower seeds, which skews the interaction between the seed and light, necessitates a sophisticated analysis. This study analyzes 326 samples using a near-infrared spectrometer to develop robust partial least squares (PLS) models. High accuracy is achieved in predicting total protein for crushed samples (r²c = 0.97, RMSEC 0.54%, RPDc 6; r²p = 0.78, RMSEP 1.24%, RPDp 2.1). Extending the scope to husked samples, promising results emerge for crude protein prediction (r²c = 0.93, RMSEC 0.86%, RPDc 3.9; r²cv = 0.83, RMSECV 1.39%, RPDcv 2.4). Additionally, this study delves into protein fractions (globulin, albumin, and glutelin) in crushed seeds, adding depth to the analysis. In conclusion, NIR spectroscopy proves valuable for rapid prescreening in breeding, especially when working with hulled grains, offering non-destructive efficiency and predictive accuracy in agricultural analysis. The novel exploration of protein fractions in sunflower seeds further enhances this study’s importance, providing a valuable contribution to the field and underscoring the practical applications of NIR spectroscopy in sustainable agriculture. In conclusion, the opacity of sunflower seed hulls poses challenges in infrared spectroscopy, limiting light penetration and accuracy. Dehulled seeds are preferred for reliable results, overcoming hull-related limitations. Although grinding provides the advantages of uniformity and reproducibility for near-infrared (NIR) spectroscopy, the preference for dehulled grains persists. The practical need for accurate analysis in agriculture and breeding drives the choice of spectroscopy on dehulled seeds, allowing for replanting. Full article

Over the past few decades, confined quantum systems have emerged to be a subject of considerable importance in physical, chemical and biological sciences. Under such stressed conditions, they display many fascinating and notable physical and chemical properties. Here we address this situation by using two plasma models, namely a weakly coupled plasma environment mimicked by a Debye-Hückel potential (DHP) and an exponential cosine screened Coulomb potential (ECSCP). On the other hand, the endohedral confinement is achieved via a Woods-Saxon (WS) potential. The critical screening constant, dipole oscillator strength (OS) and polarizability are investigated for an arbitrary state. A Shannon entropy-based strategy has been invoked to study the phase transition here. An increase in Z leads to larger critical screening. Moreover, a detailed investigation reveals that there exists at least one bound state in such plasmas. Pilot calculations are conducted for some low-lying states ($\ell =1-5$) using a generalized pseudo spectral scheme, providing optimal, non-uniform radial discretization. Full article

The Internet of Things (IoT) leads the era of interconnection, where numerous sensors and devices are being introduced and interconnected. To support such an amount of data traffic, wireless communication technologies have to overcome available spectrum shortage and complex fading channels. The transform domain communication system (TDCS) is a cognitive anti-interference communication system with a low probability of detection and dynamic spectrum sensing and accessing. However, the non-continuous and asymmetric spectrum brings new challenges to the traditional TDCS block-type pilot, which uses a series of discrete symbols in the time domain as pilots. Low efficiency and poor adaptability in fast-varying channels are the main drawbacks for the block-type pilot in TDCS. In this study, a frequency domain non-uniform pilot design method was proposed with intersecting, skewing, and edging of three typical non-uniform pilots. Some numerical examples are also presented with multipath model COST207RAx4 to verify the proposed methods in the bit error ratio and the mean square error. Compared with traditional block-type pilot, the proposed method can adapt to the fast-varying channels, as well as the non-continuous and asymmetric spectrum conditions with much higher efficiency. Full article

Comprehensive knowledge of built-in batteries in waste electrical and electronic equipment (WEEE) is required for sound and save WEEE management. However, representative sampling is challenging due to the constantly changing composition of WEEE flows and battery systems. Necessary knowledge, such as methodologically uniform procedures and recommendations for the determination of minimum sample sizes (MSS) for representative results, is missing. The direct consequences are increased sampling efforts, lack of quality-assured data, gaps in the monitoring of battery losses in complementary flows, and impeded quality control of depollution during WEEE treatment. In this study, we provide detailed data sets on built-in batteries in WEEE and propose a non-parametric approach (NPA) to determine MSS. For the pilot dataset, more than 23 Mg WEEE (6500 devices) were sampled, examined for built-in batteries, and classified according to product-specific keys (UNUkeys and BATTkeys). The results show that 21% of the devices had battery compartments, distributed over almost all UNUkeys considered and that only about every third battery was removed prior to treatment. Moreover, the characterization of battery masses (BM) and battery mass shares (BMS) using descriptive statistical analysis showed that neither product- nor battery-specific characteristics are given and that the assumption of (log-)normally distributed data is not generally applicable. Consequently, parametric approaches (PA) to determine the MSS for representative sampling are prone to be biased. The presented NPA for MSS using data-driven simulation (bootstrapping) shows its applicability despite small sample sizes and inconclusive data distribution. If consistently applied, the method presented can be used to optimize future sampling and thus reduce sampling costs and efforts while increasing data quality. Full article

The Non-Uniform Rational B-spline (NURBS) surface not only has the characteristics of the rational Bézier surface, but also has changeable knot vectors and weights, which can express the quadric surface accurately. In this paper, we investigated new bounds of the first- and second-order partial derivatives of NURBS surfaces. A pilot study was performed using inequality theorems and degree reduction of B-spline basis functions. Theoretical analysis provides simple forms of the new bounds. Numerical examples are performed to illustrate that our method has sharper bounds than the existing ones. Full article

To better understand the thermal hydraulic characteristics of the parabolic trough solar field (PTSF), a comprehensive thermal hydraulic model (CTHM) based on a pilot plant is developed in this paper. All of the main components and thermal and hydraulic transients are considered in the CTHM, and the input parameters of the model are no longer dependent on the total flow rate. In this paper, we solve the CTHM by a novel numerical approach based on graph theory and the Newton-Raphson method, and then examine it by two tests conducted based on a pilot plant. Comparing the flow rate, temperature, and pressure drop results show good agreement and further validate the availability and accuracy of the CTHM under hydraulic and thermal disturbance. Besides, two applications of the CTHM are implemented for presenting its potential function. In the first application, two cases are simulated to reveal how the thermal effects influence the PTSF behavior, and in the second application, the CHTF is used for the study of control strategies under uniform and nonuniform solar irradiance. The results verify the feasibility of controlling the PTSF outlet temperature through the header and loop valves. Full article

Tracer and pump tests including depth dependent water sampling were performed to investigate the flow conditions inside and in the vicinity of an injection well with two screen segments used for subsurface iron removal (SIR). A high resolution groundwater flow model of the well and the adjacent aquifer with vertically varying dissolved iron concentration was calibrated and used to plan measures to manipulate the vertical outflow distribution of injected oxygen enriched water. The optimized injection regime was adopted in a pilot SIR test with the aim of increasing the treatment efficacy through a depth specific injection of water using an inflatable packer. When water was injected conventionally above the pump, the outward migration of the oxygen enriched water was non-uniform and disproportional to the iron concentration and resulted in an early iron breakthrough in the lower screen. The proportion of water injected into the lower iron-rich part of the aquifer increased as a packer was placed inside the well to seal 4/5 of the upper well screen length. Thereby, the efficiency coefficient increased by 50% and iron removal by 25%. The treatment efficiency at the site suffered from low alkalinity and pH-values below 5. Higher efficiency coefficients may have been achieved by the addition of alkalis prior to injection. Full article