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Nowadays, modern visual SLAM methods attempt to deal with dynamic environments by considering the non-rigid scene assumption. This well-established approach combines geometric and semantic information to detect dynamic objects to achieve accurate localization and mapping in real environments. However, these methods need more generalization and scene awareness because of their reasoning limits due to the labeling object strategy and the need for matched keypoints. Therefore, we propose a novel method called Depth Attention Module SLAM (DAM-SLAM) that overcomes the limitations of existing methods. The main idea is to take into account the depth influence used in the geometric and semantic modules through a depth-related adaptive threshold and impact factor. Moreover, a Bayesian filter is used to refine the keypoints state estimates using a motion probability update function based on a weighting strategy related to the keypoints area (in/out of segmented object’s masks). In addition, we designed a Depth Attention Module that allows generalization to other methods by considering the non-matched keypoints and the keypoints out of segmented regions. This module estimates these keypoints state without requiring any prior semantic information by determining the interactions between the objects. We estimate this interaction through the correlation between the proximity of depth and position of these keypoints with the dynamic keypoints in a specific zone of influence of dynamic objects. The obtained results demonstrate the efficacy of the proposed method in providing accurate localization and mapping in dynamic environments.

By deploying sonic drilling for soil structure fracturing in the presence of consolidated/ unconsolidated formations, this technique greatly reduces the friction on the drillstring and bit by using energetic resonance, a bit-bouncing high-frequency axial vibration. While resonance must be avoided, to our knowledge, drilling is the only application area where resonance is necessary to break up the rocks. The problem is that the machine’s tool can encounter several different geological layers with many varieties of density. Hence, keeping the resonance of the tool plays an important role in drill processes, especially in tunnel or infrastructure shoring. In this paper, we analyze the sonic drillstring dynamics as an infinite-dimensional system from another viewpoint using the frequency domain approach. From the operator theory in defining the adequate function spaces, we show the system well-posedness. The hydraulic produced axial force that should preserve the resonant drillstring mode is defined from the spectrum study of the constructed linear operator guided by the ratio control from the top to tip boundary magnitudes.

In this paper, electrochemical anodization was used to fabricate porous layers on n-type GaAs substrates with different orientations, i.e., (511)A, (100) and (111)B, under the same experimental conditions. Scanning electron microscopy (SEM), atomic force microscopy (AFM), and x-ray diffraction (XRD) were used to characterize the formed porous layers, with respect to the substrate orientation. Results obtained from SEM and AFM data are evidence of the formation of GaAs nanocrystallites and reveal that pores grow along definite crystallographic directions. XRD analysis confirm the single crystalline structure of porous layers and a relative peak shift as compared to GaAs, indicating a change in the lattice constant due to strain effects. The photoluminescence spectra of the porous layers showed red PL bands attributed to quantum confinement effects in GaAs nanocrystallites. The investigated current–voltage (I–V) in the forward bias region demonstrates that the transport mechanism in the Au/porous-GaAs/GaAs structures was governed by space-charge-limited current (SCLC). In fact, non-saturating behavior was observed in the reverse bias I–V characteristics due to both the effective barrier height dependence on the electric field and the thermionic field emission.

In this study, a high-performance ultraviolet photodetector (UVPD) was elaborated using Cu/Au/TiO 2 /InGa structure. The chemically synthesized TiO 2 nanoparticles (NPs) decorated with plasmonic Au NPs were prepared using the solvothermal synthesis route. Different characterization techniques in particular X-ray diffraction, transmission electron microscopy, high-resolution TEM, selected area electron diffraction, energy-dispersive X-ray fluorescence, diffuse reflectance, and photoluminescence are employed in this research. The dielectric characteristics have been emphasized the frequency and bias voltage effects on electric responses through dielectric measurement. The results revealed that Au-decorated TiO 2 NPs present a giant permittivity and low dielectric loss. It was found that nanocomposites exhibited obvious photocurrent responses under illumination. The performance of our device was investigated by exposing it to a laser illumination wavelength of 375nm and at − 1 V. Under an intensity of 7.6mW, our UVPD exhibited a high responsivity of about 100A/W and a huge detectivity of 3.5 × 10 14 Jones leads to a low noise equivalent power of 3.44 × 10 –13  W.Hz −1/2 . Furthermore, the rise time/the recovery time were 0.96 and 9.6 s, respectively. These results indicate that the Au-decorated TiO 2 possesses significant photoelectric properties which can be exploited for the prospective photodetection application.

The effect of light Ni-substituted Manganese on the physical properties of La 0.2 Sr 0.8 MnO 3 perovskite prepared by the standard solid-state reaction method was investigated. Field Emission Scanning Electron microscopy confirms the particle size composition and grain boundaries in these samples. Moreover, the presence of all the chemical elements with atomic ratios coordinating with the general formula La 0.2 Sr 0.8 Mn 1− x Ni x O 3 ( x  = 0.0 and 0.1) was confirmed by Energy-dispersive X-ray spectroscopy. X-ray diffractions analyses indicate that both compounds have a rhombohedral structure with an R3C space group, for which the cell parameter increases with nickel addition. A competition between ferromagnetic and antiferromagnetic moments is evidenced at room temperature for both compounds by measuring the magnetization versus magnetic field. Saturation magnetization and the corresponding residual magnetization decrease with the Ni substitution; however, the coercive field increases. These changes are correlated with those evidenced by structural properties. Conductance measurements as a function of frequency from 10 2  Hz to 5 MHz are analyzed in the temperature range 300 K–420 K in order to evidence the conduction mechanism.

We are interested to investigate the effect of Nb 5+ addition on morphological, dielectric, and optical properties of Ba 0.97 La 0.02 Ti 1− x Nb 4 x /5 O 3 (for x  = 0.00, 0.05) ceramics. The BLT and BLT 0.95 N 0.04 were successfully synthesized by a low-cost molten-salt method. In addition, the structural phase purity of ceramics was definite by using X-ray diffraction (XRD) at room temperature (RT). Afterward, the morphology of our examples was explored using transmission electron microscopy (TEM) as well as dielectric characterizations. The dielectric constant decreased with increasing frequency. This is assigned to Maxwell–Wagner (M–W) interfacial polarization. What’s more, the room temperature photoluminescence (PL) spectra indicated a synergic effect on BLT 1− x Nb 4 x /5 ceramics. At RT, compared to BLT sample, the peaks in the visible region for doped compound are shifted to the highest wavelengths. Note also that width at mid-height reduce for Nb 5+ -doped BLT than none-doped example. Based on the photometric characterization and the results of the CIE coordinates, they discovered that synthesized perovskite may represent an appropriate candidate for semiconductor lighting devices and optoelectronic applications. Importantly, the tetragonal phases of BLT and BLT 0.95 Nb 0.04 examples can be improved by XRD and Raman spectrum. The incorporation of ions La 3+ in the Ba-site is remarkable by the peak observed about 805 cm −1 . As well, all modes show a significant broadening with the incorporation of Nb 5+ on the titanium-site.

4-Nitroaniline (PNA) is a toxic organic compound commonly found in wastewater, posing significant environmental concerns due to its toxicity and potential carcinogenicity. In this study, the recovery of PNA from aqueous solutions was investigated using a supported liquid membrane (SLM). The membrane, which consists of polypropylene Celgard 2500 (PP-Celg), was embedded with the extractant tributyl phosphate (TBP). Various factors influencing the efficiency of PNA transportation were studied, including the concentration of PNA in the source phase, pH of the source phase, NaOH concentration in the receiving phase, and choice of stripping agents. Optimal conditions for the experiment were determined to be a source phase PNA concentration of 20 ppm at pH 7, distilled water as the receiving phase, TBP as the carrier in the organic phase, and a transport time of 8 h. The extraction process was conducted under ambient temperature and pressure conditions, yielding results indicative of a first-order linearized reaction. Additionally, membrane stability and liquid membrane loss were evaluated.

This paper reports the structural, optical, and electrical properties of dysprosium oxide (Dy2O3) deposited by electron beam deposition under ultra-vacuum on porous p-type GaAs. A porous GaAs layer was produced by electrochemical anodic etching of a (100)-heavily doped p-type GaAs substrate in hydrofluoric acid (HF) and ethanol C2H5OH solution. The surface topography of the elaborated Dy2O3 layer was determined based on atomic force microscopy (AFM) images. AFM studies showed that the structure and roughness of the Dy2O3 layer were strongly dependent on the roughness and surface of porous GaAs. Dy2O3 is polycrystalline and exhibits a cubic crystalline structure, as confirmed by x-ray diffraction (XRD) analysis. The optical properties of Dy2O3/p-porous GaAs were analyzed using various techniques including ellipsometry and photoluminescence (PL) to obtain information on surface and interface quality, bandgap, optical constants, dielectric constant, and thickness. The photoluminescence (PL) spectra revealed an intense peak at 835 nm and additional weak emission peaks at 473 nm and 540 nm, respectively. The observed intense peak can be directly attributed to the interband recombination process of free carriers in the direct bandgap of p-GaAs, while the weak emission peaks at 473 nm and 540 nm correspond to 4F9/2-6H15/2 and 4F9/2-6H13/2 transitions, respectively. In the spectral region of 350 nm to 500 nm, the average thickness of the Dy2O3 layer was determined to be 11 nm. The electrical properties of the (Co/Au)/Dy2O3/p-porous GaAs metal–oxide–semiconductor (MOS) capacitor were investigated via capacitance–voltage (C–V) and conductance–voltage (G/ω–V) measurements in the temperature range of 100–400 K and frequency range of 50 Hz to 1 MHz, respectively. The experiments demonstrated that both capacitance and conductance were influenced by temperature and frequency. Additionally, the effect of temperature on interface state density (Nss) was studied, which showed that an increase in temperature led to a decrease in the interface state density (Nss) of the (Co/Au)/Dy2O3/p-porous GaAs (MOS) capacitor, as calculated by the Hill–Coleman method. The mean values of Nss for the (Co/Au)/Dy2O3/p-porous GaAs (MOS) capacitor were determined to be approximately 1012 eV−1 cm−2, making it suitable for electronic device applications. The lower values of Nss can be attributed to a low amount of local defect microstructure at the Dy2O3/p-porous GaAs interface due to the incorporation of the Dy2O3 layer into the porous GaAs. The electrical conductivity of the (Co/Au)/Dy2O3/p-porous GaAs (MOS) capacitor was studied using impedance spectroscopy in the frequency range from 50 Hz to 1 MHz at temperatures ranging from 80 K to 450 K. At low frequencies, the conductivity of alternating current (σAC) remained nearly constant, whereas at high frequencies, it increased rapidly, representing σDC and σAC, respectively. The Arrhenius plot of σAC shows two distinct slopes corresponding to two activation energies, 35 MeV and 10 MeV, in the chosen temperature range.

This study presents the synthesis of Cd0.5Zn0.5Fe2−xCrxO4 nanoparticles via the sol–gel method, along with a comprehensive characterization of their morphological, structural, infrared, and magnetic properties. The X-ray diffraction pattern confirms the formation of the spinel structure, and the cation distribution is estimated using X-ray analysis and confirmed by magnetization measurements. The crystalline size, ranging from 152 to 189 nm, and lattice parameter, varying from 8.51134 Å to 8.42067 Å, decrease with increasing Cr content. The saturation magnetization decreases from 55 emu/g to 10.8 emu/g, while the remanent magnetization increases (3.5 emu/g ≤ Mr ≤ 6.27 emu/g), and the coercivity increases (82 Oe ≤ HC ≤ 422.15 Oe) with the addition of Cr ions. Fourier transform infrared (FTIR) spectroscopy reveals two absorption bands at ν1 and ν2, located near 600 and 400 cm−1, respectively, which correspond to the vibrations of the metal–oxygen bonds in the spinel structure.