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Palembang has sustained heavy haze pollution events that are related to decrease public health quality. Because ground-based PM2.5 observation in the city has some limitations, such as spatial and temporal coverages. Thus, in this study, we applied the potential of using the surface mass concentration PM2.5 data acquired by the MERRA-2 satellite to predict daytime and night-time PM2.5 levels during heavy haze events in Palembang City. Results of the study revealed that the highest PM2.5 level was about 160 µg/m3 at 02:00 (night-time), while the lowest PM2.5 level was about 50 µg/m3 at 14:00 (daytime). Spatiotemporal variation of PM2.5 over the study area showed that more than half of the area showed PM2.5 above 90 µg/m3 at night. Stable wind conditions (2 m/s) and air temperature (29°C), and relative humidity (74%) in the study area have contributed to particulate matter accumulation. The study concluded that PM2.5 acquired by the MERRA-2 satellite could provide a new reliable source for assessing severe air pollution events. [ABSTRACT FROM AUTHOR]

It is shown that surfacing with feeding Nano oxides or Nano carbides into the weld pool leads to significant increase the wear resistance of deposited metal. Meanwhile, the information available in the literature on the optimal concentrations of Nano components corresponds only to specific surfacing conditions. Other surfacing conditions require additional experimental studies to determine optimal concentrations under these new conditions. Theoretical studies revealed that a change in the heat input of surfacing is accompanied by a change in the volume and mass of the weld pool, which leads to the changes in the mass concentrations of Nano components. It is shown that, the volume and mass of the weld pool may change almost by 3 times, and the mass percentage of Nano components by 2 times A method has been proposed for determining the mass fraction of Nano components in the weld pool at different heat inputs of surfacing. The experimental studies confirmed analytical predictions. The use of the proposed technique will make it possible to spread the technology of surfacing with feeding of Nano components into the weld pool without additional experimental studies. [ABSTRACT FROM AUTHOR]

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In the current paper, the Cauchy problem for the inhomogeneous nonlinear Schrödinger equation including inverse-square potential is considered. First, some criteria of global existence and finite-time blow-up in the mass-critical and mass-supercritical settings with 0 < c ≤ c ∗ are obtained. Then, by utilizing the potential well method and the sharp Sobolev constant, the sharp condition of blow-up is derived in the energy-critical case with 0 < c < N 2 + 4 N (N + 2) 2 c ∗ . Finally, we establish the mass concentration property of explosive solutions, as well as the dynamic behaviors of the minimal-mass blow-up solutions in the L 2 -critical setting for 0 < c < c ∗ , by means of the variational characterization of the ground-state solution to the elliptic equation, scaling techniques and a suitable refined compactness lemma. Our results generalize and supplement the ones of some previous works. [ABSTRACT FROM AUTHOR]

Mass concentration (mascon) solutions have become a prominent medium for investigating time‐variable gravity recovered by GRACE and GRACE Follow‐On. While GRACE Level‐2 spherical harmonic products require various postprocessing techniques to eliminate correlated noise, mascon formulations employ spatial regularization strategies during the estimation step to improve signal recovery. However, mascon estimation has traditionally required large computing resources and GRACE Level‐1B processing capabilities. In this study, we show that a typical mascon estimation system can be reformulated to allow for the estimation of regularized mascons from Level‐2 spherical harmonics. Provided that spherical harmonic solution covariances are available, the computed mascons will be mathematically equivalent to similar mascons estimated from Level‐1B observations. This method is computationally efficient, better leverages GRACE spherical harmonics than past methods, and matches the performance of typical mascon solutions without locking scientists into predetermined regularization designs. We develop a proof‐of‐concept solution using ITSG‐Grace2018 and compare results with traditional mascons from the Jet Propulsion Lab (JPL) and NASA Goddard Space Flight Center (GSFC). We then assess the effects of spherical harmonic truncation and use of regularization correlations on basin signal recovery. We find that spherical expansions to degree and order 60 provide the minimum expansion necessary to study most basins, while larger expansions help further localize signals. We also find that diagonal regularizations (i.e., regularizations that do not contain inter‐mascon correlations) are adversely affected by leakage, especially across boundaries such as coastlines where signals are not highly correlated, whereas including inter‐mascon correlations and regional boundaries in the regularization greatly improves signal recovery. Plain Language Summary: This study derives a new method for producing surface mass change maps in the form of so‐called "mascons" using GRACE and GRACE Follow‐On data that is computationally simpler but equally as rigorous as typically used methods. Using this method, scientists no longer need specialized orbit determination and estimation software to produce these maps, and therefore this type of work is now accessible to scientists outside of the few major centers that currently produce these maps. At the same time, centers with these specialized software packages can incorporate the computational efficiencies presented here to improve their own processes. As a result, this new method can be used to study individual problems of interest outside the scope of the globally focused solutions available today (for example, to specifically study targeted river basins), and these new studies can additionally incorporate other known information about those problems. We provide a proof‐of‐concept solution showcasing the new method and apply the new method to highlight key design decisions that must be made when producing mascon solutions. Key Points: Computationally efficient mascons computed from GRACE Level‐2 spherical harmonics are equivalent to those from Level‐1B ranging dataThese mascons can be tailored to specific problems of interest and do not require special orbit determination softwareA presented trade study shows the effects of spherical expansion truncation and compares diagonal regularization to that with correlations [ABSTRACT FROM AUTHOR]

We investigate the ground states of 3-component Bose–Einstein condensates with harmonic-like trapping potentials in ℝ 2 {\mathbb{R}^{2}} , where the intra-component interactions μ i {\mu_{i}} and the inter-component interactions β i ⁢ j = β j ⁢ i {\beta_{ij}=\beta_{ji}} ( i , j = 1 , 2 , 3 {i,j=1,2,3} , i ≠ j {i\neq j}) are all attractive. We display the regions of μ i {\mu_{i}} and β i ⁢ j {\beta_{ij}} for the existence and nonexistence of the ground states, and give an elaborate analysis for the asymptotic behavior of the ground states as β i ⁢ j ↗ β i ⁢ j * := a ∗ + 1 2 ⁢ (a ∗ - μ i) ⁢ (a ∗ - μ j) {\beta_{ij}\nearrow\beta_{ij}^{*}:=a^{\ast}+\frac{1}{2}\sqrt{{(a^{\ast}-\mu_{i% })(a^{\ast}-\mu_{j})}}} , where 0 < μ i < a ∗ := ∥ w ∥ 2 2 {0<\mu_{i}