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In this study, we investigate the Barrow holographic dark energy (BHDE) model with the Granda–Oliveros(G–O) infrared (IR) cut-off in the presence of neutrino masses, utilizing the latest observational data to address the Hubble tension. The GO cut-off is defined as |$L_{\mathrm{ IR}}=(\alpha H^2 + \beta \dot{H})^{-1/2}$|⁠. We place constraints on the total neutrino mass |$\sum m_{\nu }$| using data from Type Ia supernovae (SN) Pantheon, cosmic chronometers (CC), cosmic microwave background (CMB), Baryon Acoustic Oscillation (BAO) data sets, and Planck Lensing. Specifically, the comprehensive CMB + BAO + CC + Pantheon data set provides a total neutrino mass of |$0.118\, \text{eV}$|⁠. The parameters for the Barrow-GO model are determined to be |$\Delta = 0.0055^{+0.0086}_{-0.0086}$|⁠ , |$\alpha = 0.997^{+0.060}_{-0.060}$|⁠ , and |$\beta = 0.598^{+0.080}_{-0.080}$|⁠ , showing good agreement with previous studies. One of the key findings of this study is the model's ability to alleviate the Hubble tension, as evidenced by the comparison of |$H_0$| measurements. Specifically, the tension value for the combination of data set (CMB + BAO + CC + Pantheon + Lensing) is |$1.5\sigma$| with the Planck 2018 and |$1.4\sigma$| with R22. These results underscore the importance of multi-data set integration in refining constraints on neutrino properties and highlight the model's efficacy in probing fundamental aspects of neutrino physics. Our results demonstrate that the BHDE model with the GO cut-off can effectively address the Hubble tension, offering a coherent framework that reconciles local and cosmological measurements of the Hubble constant. [ABSTRACT FROM AUTHOR]

This study investigates the cosmic bulk flow through an analysis of luminosity distance variations in a perturbed Friedmann universe governed by f (R) gravity. The Hubble parameter, derived from perturbed Friedmann equations capturing intrinsic temporal fluctuations, is crucial. Redshift tomography is used to analyse observational data from the Pantheon catalogue from 0.015 to z < 2.3. Our objective is to constrain the cosmic bulk flow's direction and magnitude within this redshift range. At low redshifts (z < 0.06), the predominant bulk flow aligns with the dominating supercluster in the corresponding range, maintaining a relatively constant magnitude, consistent with Lambda cold dark matter (ΛCDM) model predictions. A shift towards (l, b) = (290 ± 21, 15 ± 20) with |$v_{\mathrm{bulk}} = 774 \pm 83 \, \mathrm{km\, s}^{-1}$| occurs between 0.06 < z < 0.1, coinciding with the cosmic microwave background dipole. For 0.1 < z < 0.2, the bulk flow shifts to (l, b) = (270 ± 21, 25 ± 20) with |$v_{\mathrm{bulk}} = 903 \pm 102 \, \mathrm{km\, s}^{-1}$|⁠ , supporting Kashlinsky et al.'s result. Beyond z > 0.2, the bulk flow's magnitude exceeds |$1000 \, \mathrm{km\, s}^{-1}$|⁠ , deviating from ΛCDM model expectations. Our findings suggest that matter density oscillations under f (R) gravity exhibit ΛCDM model properties at low redshifts. However, the microwave background anisotropy shows noticeable fluctuations at higher redshifts, validating prior findings of strong cosmic bulk flows at these scales. [ABSTRACT FROM AUTHOR]

Yttria-doped zirconia ceramics have many applications in a wide range of industries mainly due to their excellent mechanical properties, corrosion resistance and biocompatibility. In this study, micromechanical properties of yttria-doped zirconia produced by Direct-Ink Writing (DIW) were investigated and compared to the ones produced by Cold Isostatic Pressing (CIP). In doing so, mechanical response was assessed at different length scales, from macro- up to submicrometric-, by means of Vickers hardness, nanoindentation, and nanoscratch tests. Microstructure was also characterized by determining grain size, crystal structure and phase tetragonal to monoclinic phase transformation. Results revealed that printed samples displayed 20–25% lower hardness values compared to those exhibited by the respective CIP pairs. Differences in hardness between 3 and 8 mol% yttria content evaluated for CIP samples were slight for printed samples, due to the effect of microstructural defects like porosity, resulting from the processing parameters used. At the local level, such an effect was found to be lower. In this sense, hardness and elastic modulus achieved by nanoindentation were closer, when comparing printed and CIP samples. Scratch tests carried out from 0 to 250 mN revealed that 3 mol% Y 2 O 3 samples developed micro-fracture events in the track length, being the printed samples the ones heavily deformed. [ABSTRACT FROM AUTHOR]

Understanding and optimization the rheological properties characterization of zirconia (ZrO 2) based ceramics inks is critical for optimizing the production of Direct Ink Writing (DIW) components to achieve complex structures with similar properties as those obtained by using the traditional processing routes. In this work, ZrO 2 based ceramic materials with different yttrium contents (3 and 8 mol %) were designed and produced by DIW to determine the most suitable ceramic ink composition in terms of the rheological properties (e.g. flow curves, viscosity, loss modulus G′, storage modulus G″, etc.) to design new components. Different ceramic inks with charges up to 75 wt % were prepared and characterized. A systematic study of the feedstock, as well as the different ceramic inks, was performed to determine the optimal ceramic charge. This characterization evidences that rheological properties of zirconia based ceramic inks are influenced by the particle size and amount of ceramic content. Furthermore, the rheological study highlights that the ZrO 2 inks present a Non-Newtonian behavior depending on the ceramic content. Results revealed that the yttrium content affects the flow properties of ZrO 2 suspensions in such a way that, higher shear rate was required to make the suspensions flow at increasing the amount of powder. It was also found that the best rheological properties corresponded to 73 and 70% for the 3Y- and 8Y–ZrO 2 of ceramic charge, respectively. [ABSTRACT FROM AUTHOR]

This paper is an attempt for solving operator-valued quantum stochastic optimal control problems, in Fock space. For this purpose, the dynamics of the classical system state is described by Hudson–Parthasarathy type Quantum Stochastic Differential Equation (QSDE) in Fock space and then by associating a quadratic performance criterion with the QSDE, a Quantum Stochastic Linear Quadratic Regulator (QS-LQR) optimal control problem is formulated. Also, an algorithm for solving the QS-LQR optimal control problem is designed. For solving the resulting optimal control problem, a new HJB equation is obtained. Thereby, the operator valued control process is obtained. Two theorems are proved to facilitate the algorithm. In this paper, for the first time, the optimal strategy for trading stock is designed via the presented method. For this purpose, Merton portfolio allocation problem is solved. The simulation results show that portfolio optimal performances, minimum risk and maximum return are achieved via presented method. [ABSTRACT FROM AUTHOR]

Abstract The purpose of this paper is to design an optimal quantum controller for a class of stochastic systems with application in financial problems. Dynamics of the system is prescribed via a Quantum Stochastic Differential System (QSDES) with a quantum Brownian motion on a quantum probability space. A theorem for guaranteeing the existence and uniqueness of solutions to the QSDES is proved. Additionally, a new optimal stochastic control problem is formulated and based on the necessary optimality conditions, an optimal quantum control law is designed, explicitly. Four theorems and two lemmas, for facilitating the optimal controller design algorithm, are proved. Finally, for demonstrating the applicable results, two financial problems, Merton portfolio allocation and optimal pairs trading problem are simulated by using the presented method. As the simulation results indicate, portfolio optimal performances, minimum risk and maximum return, are achieved via presented method. Highlights • The state of a stochastic system is modeled as a quantum diffusion process via a new Quantum Stochastic dynamics. • An existence and uniqueness solution theorem for QSDE is proved. • The explicit optimal quantum control laws are designed. • Spread evolution Modelling, more precisely and increasing portfolio managing are achieved. [ABSTRACT FROM AUTHOR]

In this study, the effects of ferrofluids on the forced convective heat transfer in a tube with a round cross section under constant heat flux in the laminar flow regime are investigated experimentally. For this purpose, an experimental setup was designed and built. Furthermore, the effects of an external magnetic field on the forced convective heat transfer were examined for various Reynolds numbers and volume concentrations. The parameters of magnetic field strength, magnetic field arrangement, the constancy or oscillation of the magnetic field and also its oscillatory mode were examined. As a result of the experimental studies, in the absence of a magnetic field enhancement in convective heat transfer was observed after using the ferrofluid compared with distilled water. In addition, convective heat transfer through the circular tube increased after using an oscillatory magnetic field. However, the heat transfer decreased after a constant magnetic field was applied. Based on the results obtained, the effects of the magnetic field are more intensified in the ferrofluids with higher volume concentration and flows with lower Reynolds number. Moreover, the effect of the oscillation frequency on the local heat transfer coefficient varies in different oscillatory modes of the magnetic field. The maximum enhancement of 19.8% was obtained in the local convective heat transfer by using the oscillating magnetic field compared with the case no magnetic field was applied. [ABSTRACT FROM AUTHOR]

The notion of quasi-Einstein metric in physics is equivalent to the notion of Ricci soliton in Riemannian spaces. Quasi-Einstein metrics serve also as solution to the Ricci flow equation. Here, the Riemannian metric is replaced by a Hessian matrix derived from a Finsler structure and a quasi-Einstein Finsler metric is defined. In compact case, it is proved that the quasi-Einstein metrics are solutions to the Finslerian Ricci flow and conversely, certain form of solutions to the Finslerian Ricci flow are quasi-Einstein Finsler metrics. [ABSTRACT FROM AUTHOR]

The two near-identical pushbroom Thermal Infrared Sensors (TIRS) aboard Landsat 8 and 9 are currently imaging the Earth's surface at 10.9 and 12 microns from similar 705 km altitude, sun-synchronous polar orbits. This work validates the consistency in the imaging data quality, which is vital for harmonization of the data from the two sensors needed for global mapping. The overlapping operation of these two near-identical sensors, launched eight years apart, provides a unique opportunity to assess the sensitivity of the conventionally used metrics to any unexpectedly found nuanced differences in their spatial performance caused by variety of factors. Our study evaluates spatial quality metrics for bands 10 and 11 from 2022, the first complete year during which both TIRS instruments have been operational. The assessment relies on the straight-knife-edge technique, also known as the Edge Method. The study focuses on comparing the consistency and stability of eight separate spatial metrics derived from four separate water–desert boundary scenes. Desert coastal scenes were selected for their high thermal contrast in both the along- and across-track directions with respect to the platforms ground tracks. The analysis makes use of the 30 m upsampled TIRS images. The results show that the Landsat 8 and Landsat 9 TIRS spatial performance are both meeting the spatial performance requirements of the Landsat program, and that the two sensors are consistent and nearly identical in both across- and along-track directions. Better agreement, both with time and in magnitude, is found for the edge slope and line spread function's full-width at half maximum. The trend of averaged modulation transfer function at Nyquist shows that Landsat 8 TIRS MTF differs more between the along- and across-track scans than that for Landsat 9 TIRS. The across-track MTF is consistently lower than that for the along-track, though the differences are within the scatter seen in the results due to the use of the natural edges. [ABSTRACT FROM AUTHOR]

In this paper, we present a detailed analysis of the dark energy dipole using Union2, Pantheon and GRB dataset in Chameleon and Teleparallel dark energy models, in comparison with Λ CDM. Both models are extensively studied in recent years and our result shows that with Union2 and Pantheon data, the preferred direction of the anisotropy in both models are very close to each other as well as with those obtained in some studies for Λ CDM. However, when the models fitted with a combination of Union 2 and GRB, the statistical analysis slightly favors the Chameleon cosmology over Teleparallel gravity, with the maximum anisotropic direction of (l = 330 - 28 + 30 , b = - 15 - 25 + 23 ) in galactic coordinate system, comparable with α -dipole result in Keck-VLT data and LCDM. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate and rank the key factors affecting abrasive and corrosive wear of grinding media using fuzzy Delphi analytic hierarchy (FDAHP) method in grinding of copper sulphide minerals. There are many factors that affect the abrasive and corrosive wear of grinding media. Weight of each impact factor must be determined by using comprehensive scenario that is involved all the predicable grinding media wear issues. FDAHP applied to determine the importance degree of each factor. Significance of 27 effective main parameters is evaluated. The results indicate that composition and metallurgical properties of the grinding media, ore mineralogy, pulp viscosity, rheological properties and water chemistry throughout of grinding circuit and speed of the mill have the greatest weight in the abrasive wear. Moreover, composition and metallurgical properties of the grinding media, galvanic interaction between grinding media and mineral, ore mineralogy, water chemistry, pH, Eh and solid content had the highest degree of importance in corrosive wear, respectively. Furthermore, gas purging, Eh and discharge type of mill were the least significant factors in abrasive wear. Additionally, discharge type, diameter and speed of the mill were the least important factors in corrosive wear. [ABSTRACT FROM AUTHOR]

Abstract: In this study, PM10, PM2.5, and PM1 concentrations were measured from April through September 2010. These measurements were made every six days and on days with dust events using a Grimm Model 1.177 aerosol spectrometer. Meteorological data were also collected. Overall mean values of 319.6 ± 407.07, 69.5 ± 83.2, and 37.02 ± 34.9 μg/m3 were obtained for PM10, PM2.5, and PM1, respectively, with corresponding maximum values of 5337.6, 910.9, and 495 μg/m3. The presence of the westerly prevailing wind implied that Iraq is the major source of dust events in this area. A total of 72 dust days and 711 dust hours occurred in the study area. The dust events occurred primarily during July. The longest dust event during the study period occurred in July, lasted five days, and had a peak concentration of 2028 μg/m3. These high concentrations produced AQI values of up to 500. A total estimated mortality and morbidity of 1131 and 8157 cases, respectively, can be attributed to these concentrations. The results of this study indicated the importance of dust events in Ahvaz and their possible health impacts. The study also demonstrated the need to design and implement intergovernmental management schemes to effectively mitigate such events. [Copyright &y& Elsevier]

Abstract: In the present investigation the relationship between collection zone rate constant (k c) and gas dispersion parameters, viz. bubble size (d b), superficial gas velocity (J g), gas hold-up (ε g) and bubble surface area flux (S b) was evaluated. Experiments were conducted in an industrial (4m in diameter and 12m high) and a pilot (0.1m in diameter and 4m high) flotation column in rougher circuit at Miduk copper concentrator in Iran. Gas hold-up was measured using pressure difference technique and mean bubble sizes were estimated from a drift flux analysis. It was found that the collection zone rate constant was not correlated with d b and J g solely but was linearly dependent on ε g and S b for the range of interest. Collection efficiency (E k) and floatability factor (P) in the industrial columns were quantified (E k =3.1%; P =7.7×10−3). The influence of operating parameters comprising superficial gas velocity, slurry solids% and frother dosage/type on S b and flotation kinetics was discussed. Analysis of available industrial data suggested that S b and ε g were related by S b =4.46ε g over the range 30< S b <60s−1 and 7%< ε g <14%. [Copyright &y& Elsevier]

Abstract: In this investigation the froth zone of an industrial column (4m “diameter”×12m “height”) in rougher circuit was characterized. Experiments were carried out at Miduk copper concentrator, Iran. Miduk is a unique copper processing plant which utilizes columns in rougher circuit. Cleaning and selectivity actions in the rougher froth were illustrated using solids and grade profiles along with RTD data. The impact of froth depth (FD) on overall rate constant (k) and k–S b relationship was evaluated. Dependency of overall flotation kinetics on froth depth and gas velocity (J g) was modeled by k =4.97(FD)−0.87(J g)0.80. Froth recovery (R f) was estimated and modeled in terms of froth residence time of slurry (FRTSlurry) as R f = R f,maxexp(−k ×FRTSlurry). Finally, the correlation between k, S b (indicative of the collection zone performance) and FRTSlurry (indicative of the froth zone performance) was modeled by k =0.02 (FRTSlurry)−0.62(S b)0.82. [Copyright &y& Elsevier]

Abstract: In this investigation, a pilot-scale flotation column was successfully designed, installed and tested in rougher circuit of the Miduk copper concentrator, Iran. The axial dispersion model was employed in the design procedure. Collection zone rate constant (k c) along with the target recovery of over 75% was used to size the column. The rate constant k c was determined based on a number of pilot and industrial experiments. Performance of the pilot column was compared with existing full-scale Microcel columns in a number of parallel experiments. [Copyright &y& Elsevier]