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The synthesis of copper nanowires (CuNWs) using modified polyols with hexadecylamine or octadecylamine as capping agents, known for their ease of operation, rapid reaction, and suitability for mass production, often encounters challenges such as the presence of copper particles, numerous copper nanorods, difficulty in purifying organic compounds, and air instability as by-products. In addressing these issues, this study introduces an innovative multiphase ultrasonic-assisted separation method. By utilizing ultrasound to accelerate the dissolution of hexadecylamine and facilitate the separation movement of CuNWs and by-products in hydrophilic and hydrophobic phases, the aim of achieving high purification of CuNWs is realized. Through the introduction of an ultra-thin hexadecylamine layer (~ 3.5 nm) on the surface of CuNWs and leveraging the active adsorption of silver seed crystals, combined with the control CuNWs reaction concentration, silver-coated CuNWs with a dense and uniform surface thickness of 12–15 nm are obtained. By enhancing purity, stability, and cost-effectiveness, this research represents a significant advancement in the field of one-dimensional nanowires and their devices. [ABSTRACT FROM AUTHOR]

Forensic audio analysis is a foundation stone of many crime investigations. In forensic evidence; the audio file of the human voice is analyzed to extract much information in addition to the content of the speech, such as the speaker's identity, emotions, gender, origin, etc. The accurate determination of individuals into groups based on their age development stage and their gender are often used as early investigations to differentiate them and determine the legal rights and responsibilities associated with them. This work introduces a light CNN model with a new architecture to detect the human age-evolution being's stage (kids or adults) at the same time the gender of the adult one (male or female) based on the individual's voice characteristics, which offers a balance between computational efficiency and model accuracy. The temporal information in the audio file is prepared by scaled and normalized. Then this information is exploited to extract and track the unique and salient audio features that make up the pattern of the feature map for each target class through some convolutional layers followed by maxpooling layers. Finally, The decision is made based on these feature maps by some fully connected layers. Successful and promising results are accomplished in terms of accuracy and loss functions which realize 0.99 and 0.017 respectively over the riched Voxceleb2 dataset. The proposed model underscores the importance of leveraging Light DNNs for gender and age-evolution detection, offering a robust and ethically sound solution for real-world applications in the field of audio forensics such as span speaker identification, victim profiling, deception detection, and more, contributing to the advancement of audio forensic analysis. [ABSTRACT FROM AUTHOR]

The bamboo-shaped SiC nanowires reinforced SiC dense coating (dense SiCNWbs/SiC coating) was successfully designed on the graphite by polymer pyrolysis chemical vapor deposition (PPCVD) combined with chemical vapor deposition (CVD) method. By analyzing the thermal decomposition of the mixed powder of PCS and activated carbon, it was determined that the porous bamboo-shaped SiC nanowires layer could be grown by the PPCVD technology based on a dual-temperature zone whose optimal temperatures were determined to be 800 ℃ + 1200 ℃. SEM results showed that the porous layer prepared by the catalyst solution of 0.1 mol/L and holding time of 2 h was easier for the subsequent SiC densification. As expected, the dense SiCNWbs/SiC coating (SS1 coating) was successfully fabricated. Compared with the loose coating, the SS1 coating showed better performance. SS1 coating possessed better crystallinity. The bonding strength between the coating and the substrate was 11.96 MPa, and the weight loss was just 0.79% after oxidation at 1500 ℃ for 60 h, which showed the potential of excellent anti-oxidation protection. Finally, the forming mechanism of the dense coating was revealed, which provided a theoretical basis for the forming and application of the dense anti-oxidation coating of C/C composites. [ABSTRACT FROM AUTHOR]

Drones are currently being used in a wide range of useful tasks that are too dangerous or/and expensive to be performed by humans. However, this is increasingly developing security breaching issues due to the possibility of misuse of unmanned aircraft in illegal activities such as drug smuggling, terrorism, etc. Thus, the detection and tracking of drones are becoming a crucial topic. Unfortunately, due to the drone's small size, its detection methods are generally unreliable: high false alarm rate, low accuracy rate, and low detection speed are well-known aspects of this detection. The new emerging real-time algorithm based on the improved "You Only Look Once" (YOLO-V3) algorithm is proposed here for drone detection. This newly designed algorithm comprises multiple phases and has shown the potential to outperform the traditional detection approaches. The proposed algorithm enhances the performance of YOLO-V3 by designing and building a CNN to solve the problem of a large number of YOLO-V3 parameters, using densely connected modules to enhance the interlayer connection of CNNs and further strengthen the connection between dense neural network blocks, and finally improving the YOLO-V3 multiple-scale detection by expanding the three-scale to four-scale detection to increase the accuracy of detecting small objects like drones. The evaluation results of our algorithm obtain 96% on average precision and 95.60% accuracy. [ABSTRACT FROM AUTHOR]

While establishing the bijection between near-ring congruences and various types of ideals of seminearrings, different kinds of restrictions were imposed either on the seminearrings under consideration or on the near-ring congruences. In this paper we consider a seminearring S without any restriction and establish that there exists an inclusion preserving bijective correspondence between the set { I ⊆ S : I is a strong, dense, reflexive and closed additive subsemigroup of S with I S ⊆ I } and the set of all near-ring congruences on S. We also show that in any seminearring S, there exists an inclusion preserving bijective correspondence between the set { I ⊆ S : I is a strong, dense, reflexive and closed additive subsemigroup of S with I S , S I ⊆ I } and the set of all zero-symmetric near-ring congruences on S. [ABSTRACT FROM AUTHOR]

Purpose: Right ventricular (RV) function is increasingly recognized for its prognostic value in many disease states. As with the left ventricle (LV), strain-based measurements may have better prognostic value than typical chamber volumes or ejection fraction. Complete functional characterization of the RV requires high-resolution, 3D displacement tracking methods, which have been prohibitively challenging to implement. Zonal excitation during Displacement ENcoding with Stimulated Echoes (DENSE) magnetic resonance imaging (MRI) has helped reduce scan time for 2D LV strain quantification. We hypothesized that zonal excitation could alternatively be used to reproducibly acquire higher resolution, 3D-encoded DENSE images for quantification of bi-ventricular strain within a single breath-hold. Methods: We modified sequence parameters for a 3D zonal excitation DENSE sequence to achieve in-plane resolution < 2 mm and acquired two sets of images in eight healthy adult male volunteers with median (IQR) age 32.5 (32.0–33.8) years. We assessed the inter-test reproducibility of this technique, and compared computed strains and torsion with previously published data. Results: Data for one subject was excluded based on image artifacts. Reproducibility for LV (CoV: 6.1–9.0%) and RV normal strains (CoV: 6.3–8.2%) and LV torsion (CoV = 7.1%) were all very good. Reproducibility of RV torsion was lower (CoV = 16.7%), but still within acceptable limits. Computed global strains and torsion were within reasonable agreement with published data, but further studies in larger cohorts are needed to confirm. Conclusion: Reproducible acquisition of 3D-encoded biventricular myocardial strain data in a breath-hold is feasible using DENSE with zonal excitation. [ABSTRACT FROM AUTHOR]

With the development of quality of life, people pay more and more attention to the surrounding environmental factors, especially air pollution. The problem of air pollution in China is becoming more and more serious, which poses a great threat to people's health. Therefore, the prediction of air quality concentration is very important. PM2.5 is the primary indicator for evaluating the concentration of smog. Currently, studies have been proposed to predict the concentration of PM2.5. Before, most methods use traditional machine learning or real-time monitoring to predict pollution of PM2.5 value. However, the previous prediction methods cannot meet the requirement of the accuracy. For this end, this paper uses Convnet and Dense-based Bidirectional Gated Recurrent Unit to predict PM2.5 value which combined Convnet, Dense and Bi-GRU. The feature in air quality data was extracted from convnets without max-pooling instead another convolutional layer and Bi-GRU with additional Dense could provide a more accuracy result. Experiments show that the effectiveness of our method PM2.5 mass concentration prediction model provides a more superior method for PM2.5 mass concentration prediction. [ABSTRACT FROM AUTHOR]

Single-image dehazing is an ill-posed problem. Most previous methods focused on estimating intermediate parameters for input hazy images. In this paper, we propose a novel end-to-end Simplified Non-locally Dense Network (SNDN) which does not rely on intermediate parameters. To capture long-range dependencies, we propose a Simplified Non-local Dense Block (SNDB) which is lightweight and outperforms traditional non-local method. Our SNDB will be embedded into a densely connected encoder–decoder network. To avoid gradients vanishing problem, we propose a simple branch network which only have five convolution layers. The effectiveness of our proposed network is proved through ablation experiment. In addition, we enhanced our training set by synthesizing colored hazy images, which helps restore the original color of the hazy image. The experimental results demonstrate that our network have better performance than most of the pervious state-of-the-art methods. [ABSTRACT FROM AUTHOR]

This article presents an analysis of the discussion and written work produced during an experiment in which two students in teacher training were asked to solve a version of the fixed-point problem initially proposed by Pontille, Feurly-Reynaud and Tisseron. Our interest lies in how the problem can be broken down into five tasks (proposed by us), and specifically the effect of an intermediary phase involving the set of numbers that have a maximum of five decimal places. We are also interested in how the students reorient their mathematical work based on the hints and clues provided by the researchers. In our analysis, we discuss─as much from an epistemological perspective as from a cognitive perspective─the problem of how to conceptualize/coordinate the properties of density and completeness when it comes to extending the set of rational numbers to the set of real numbers. We are particularly interested in the property of density (intrinsic, with respect to order) in ordered sets D and Q and the role it can play in the learner's ability to separate the numerical-arithmetic structure of the theoretical "real axis" from its representation in the figural register, which, according to our analysis, is one of the key aspects in the conceptualization of R. [ABSTRACT FROM AUTHOR]

Objective: Develop an accelerated cine displacement encoding with stimulated echoes (DENSE) cardiovascular magnetic resonance (CMR) sequence to enable clinically feasible myocardial strain evaluation in patients with dilated cardiomyopathy (DCM). Materials and methods: A spiral cine DENSE sequence was modified by limiting the field of view in two dimensions using in-plane slice-selective pulses in the stimulated echo. This reduced breath hold duration from 20RR to 14RR intervals. Following phantom and pilot studies, the feasibility of the sequence to assess peak radial, circumferential, and longitudinal strain was tested in control subjects (n = 18) and then applied in DCM patients (n = 29). Results: DENSE acquisition was possible in all participants. Elements of the data were not analysable in 1 control (6%) and 4 DCM r(14%) subjects due to off-resonance or susceptibility artefacts and low signal-to-noise ratio. Peak radial, circumferential, short-axis contour strain and longitudinal strain was reduced in DCM patients (p < 0.001 vs. controls) and strain measurements correlated with left ventricular ejection fraction (with circumferential strain r = − 0.79, p < 0.0001; with vertical long-axis strain r = − 0.76, p < 0.0001). All strain measurements had good inter-observer agreement (ICC > 0.80), except peak radial strain. Discussion: We demonstrate the feasibility of CMR strain assessment in healthy controls and DCM patients using an accelerated cine DENSE technique. This may facilitate integration of strain assessment into routine CMR studies. [ABSTRACT FROM AUTHOR]

We show that every MV-algebra A can be naturally equipped with a filter topology such that A is a topological MV-algebra, which improves the main results on C-topological lattice-ordered groups in both Yang (Sci China Ser A 52(11):2397-2403, 2009) and Gusić (Proc Am Math Soc 126(9):2593-2597, 1998). Furthermore, for a 2-divisible MV-algebra A, we show that the filter topological space is Hausdorff if and only if A is semisimple. [ABSTRACT FROM AUTHOR]

Technology of water-stabilized plasma torch was recently substantially updated through introduction of a so-called hybrid concept that combines benefits of water stabilization and gas stabilization principles. The high-enthalpy plasma provided by the WSP-H ('hybrid') torch may be used for thermal spraying of powders as well as liquid feedstocks with high feed rates. In this study, results from three selected experiments with suspension plasma spraying with WSP-H technology are presented. Possibility of deposition of coatings with controlled microstructures was demonstrated for three different ceramics (YSZ-yttria-stabilized zirconia, YAG-yttrium aluminum garnet and AlO) introduced into ethanol-based suspensions. Shadowgraphy was used for optimization of suspension injection and visualization of the liquid fragmentation in the plasma jet. Coatings were deposited onto substrates attached to the rotating carousel with integrated temperature monitoring and air cooling, which provided an excellent reproducibility of the deposition process. Deposition of columnar-like YSZ and dense YAG and AlO coatings was successfully achieved. Deposition efficiency reached more than 50%, as evaluated according to EN ISO 17 836 standard. [ABSTRACT FROM AUTHOR]

By estimating the first-order (direction) and second-order (curvature) derivatives in an image, the parameters of a line or circle passing through a point may be uniquely defined in most cases. This allows to compute a one-to-one Hough transform, every point in the image space voting for one unique point in the parameter space. Moreover, those parameters can be directly estimated on the greyscale image without the need to calculate the contour and without reducing the spatial support of the Hough transform, i.e. densely on the whole image. The general framework using multiscale derivatives is presented, and the one-to-one Hough dense transforms for detecting lines and circles are evaluated and compared with other variants of Hough transforms, from qualitative and computational points of view. [ABSTRACT FROM AUTHOR]

Experiments were performed with a particle tracking velocimetry system to investigate the behaviour of inclined negatively buoyant jets with source angles of 15°, 30°, 45°, 60°, 65°, 70°, and 75° in stationary ambient conditions. Velocities were measured in a plane aligned with the central axis of the flow and the experiments were designed such that the flow did not interact with boundaries in the region were the flow behaviour was measured. The results of this study complement previous research, which has largely focused on the mean geometric characteristics and the mean dilution of the discharged fluid. Geometric characteristics, spreading rates, and time-averaged (mean) centreline velocity results are compared with relevant experimental results from previous studies and integral model predictions. Axial and transverse mean velocity profiles at maximum height and the return point provide additional insights into the detrainment of discharged fluid due to the unstable density gradient on the inner side of the flow. [ABSTRACT FROM AUTHOR]

This paper deals with dense optical flow estimation from the perspective of the trade-off between quality of the estimated flow and computational cost which is required by real-world applications. We propose a fast and robust local method, denoted by eFOLKI, and describe its implementation on GPU. It leads to very high performance even on large image formats such as 4 K (3,840 × 2,160) resolution. In order to assess the interest of eFOLKI, we first present a comparative study with currently available GPU codes, including local and global methods, on a large set of data with ground truth. eFOLKI appears significantly faster while providing quite accurate and highly robust estimated flows. We then show, on four real-time video processing applications based on optical flow, that eFOLKI reaches the requirements both in terms of estimated flows quality and of processing rate. [ABSTRACT FROM AUTHOR]

Because of its importance in optimization theory, the concept of convexity has been generalized in various ways. With these generalizations, to seek some practical criteria for them is especially important. In this paper, some criteria are developed for semi-prequasi-invexity, which includes prequasi-invexity as the special case. Mutual characterizations among semi-prequasi-invex functions, strictly semi-prequasi-invex functions, and strongly semi-prequasi-invex functions are presented. [ABSTRACT FROM AUTHOR]

Let s denote the q-ary sum-of-digits function and let $${P_1(X), P_2(X) \in \mathbb{Z}[X]}$$ with $${P_1(\mathbb{N}), P_2(\mathbb{N}) \subset \mathbb{N}}$$ be polynomials of degree $${h, l \geqq 1, h \neq l}$$ , respectively. In this note we show that ( $${s_q(P_1(n))/s_q(P_2(n)))_{n \geqq 1}}$$ is dense in $${\mathbb{R}^+}$$ . This extends work by Stolarsky [] and Hare, Laishram and Stoll []. [ABSTRACT FROM AUTHOR]

Fast cine displacement encoding with stimulated echoes (DENSE) has comparative advantages over tagged MRI (TMRI) including higher spatial resolution and faster post-processing. This study computed regional radial and circumferential myocardial strains with DENSE displacements and validated it in reference to TMRI, according to American Heart Association (AHA) guidelines for standardized segmentation of regions in the left ventricle (LV). This study was therefore novel in examining agreement between the modalities in 16 AHA recommended LV segments. DENSE displacements were obtained with spatiotemporal phase unwrapping and TMRI displacements obtained with a conventional tag-finding algorithm. A validation study with a rotating phantom established similar shear strain between modalities prior to in vivo studies. A novel meshfree nearest node finite element method (NNFEM) was used for rapid computation of Lagrange strain in both phantom and in vivo studies in both modalities. Also novel was conducting in vivo repeatability studies for observing recurring strain patterns in DENSE and increase confidence in it. Comprehensive regional strain agreements via Bland-Altman analysis between the modalities were obtained. Results from the phantom study showed similar radial-circumferential shear strains from the two modalities. Mean differences in regional in vivo circumferential strains were −0.01 ± 0.09 (95% limits of agreement) from comparing the modalities and −0.01 ± 0.07 from repeatability studies. Differences and means from comparison and repeatability studies were uncorrelated ( p > 0.05) indicating no increases in differences with increased strain magnitudes. Bland-Altman analysis and similarities in regional strain distribution within the myocardium showed good agreements between DENSE and TMRI and show their interchangeability. NNFEM was also established as a common framework for computing strain in both modalities. [ABSTRACT FROM AUTHOR]

We give topological proofs of Görnemann's adaptation to Heyting algebras of the Rasiowa-Sikorski Lemma for Boolean algebras; and of the Rauszer-Sabalski generalisation of it to distributive lattices. The arguments use the Priestley topology on the set of prime filters, and the Baire category theorem. This is preceded by a discussion of criteria for compactness of various spaces of subsets of a lattice, including spaces of filters, prime filters etc. [ABSTRACT FROM AUTHOR]

Let G be a non-empty closed (resp. bounded closed) boundedly relatively weakly compact subset in a strictly convex Kadec Banach space X. Let K(X) denote the space of all non-empty compact convex subsets of X endowed with the Hausdorff distance. Moreover, let KG(X) denote the closure of the set {A &epsiv; K(X): A ∩ G = Ø}. We prove that the set of all A &epsiv; KG(X) (resp. A &epsiv; K (X)), such that the minimization (resp. maximization) problem min(A, G) (resp. max(A, G)) is well posed, contains a dense Gδ-subset of KG(X) (resp. K(X)), thus extending the recent results due to Blasi, Myjak and Papini and Li. [ABSTRACT FROM AUTHOR]

To predict the characteristics of dense liquid-solid two-phase flow, K-ε-T model is established, in which the turbulent flow of fluid phase is described with fluid turbulent kinetic energy K f and its dissipation rate ɛ f , and the particles random motion is described with particle turbulent energy K p and its dissipation rate ɛ p and pseudothermal temperature T p . The soverning equations are also derived. With K-ε-T model, numerical study of dense liquid-solid two-phase turbulent up-flow in a pipe is performed. The calculated results are in good agreement with experimental data of Alajbegovic et al. (1994), and some flow features are captured. [ABSTRACT FROM AUTHOR]