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Optimal scheduling for multi-ESS considering life-cycle battery degradation
No full textIn this study, we propose an optimal strategy for managing multiple energy storage systems (ESS) to reduce both electricity expenses and battery degradation costs. Our approach uses a two-stage optimization process for battery management. In the first stage, reinforcement learning (RL) identifies the aggregated optimal amounts for charging and discharging. Then, quadratic programming (QP) distributes these aggregated amounts across multiple batteries. Experiments conducted under different test conditions, including variations in the number of batteries and their remaining lifespans, show that ESS with reused batteries can improve operational efficiency and achieve total cost savings of 1.7% to 11.2% compared to ESS with new batteries
On the penalization by the perimeter in shape optimization applied to Dirichlet inverse obstacle problem
No full textThis paper is devoted to the understanding of regularization process in the shape optimization approach to the so-called Dirichlet inverse obstacle problem for elliptic operators. More precisely, we study two different regularizations of the very classical shape optimization approach consisting in minimizing a mismatched functional. The first one is an implicit regularization when working in the class of inclusion having a uniform ε-cone property, a natural class in shape optimization. As this regularity is not trivial to guarantee numerically, we discuss the regularization by perimeter penalization. We show that this second regularization provides a stability gain in the minimization process
Design and characterization of ultrasonic transducer array system for targeted non-invasive treatment
No full textThis paper presents the design, simulation, and experimental characterization of an ultrasonic transducer array system using open-source hardware for targeted non-invasive therapeutic applications. Two array geometries, Uniform Rectangular Array (URA) and Concentric Circular Array (CCA), were evaluated based on their pressure field distributions and beam focusing capabilities. The design process is described together with numerical simulations and experiments and reveals URA’s superior acoustic focusing and pressure uniformity. Developed largely through undergraduate research, this work represents an engineering proof-of-concept conducted at 40 kHz, which is below the medical therapeutic range (1–4 MHz). While this work does not imply its efficacy in biological systems or direct clinical applicability at present, it lays the groundwork for non-invasive therapeutic ultrasound systems with future design optimization aimed at applications such as cystic fibrosis and neurological conditions
Three-dimensional metal ion flow in the polar ionosphere simulated by a new ionospheric model
No full textThe temporal evolution of the three-dimensional metal ion flow (MIF) is crucial for polar sporadic E layer dynamics. Yet, until now it has not been studied in detail. Here, we present a new ionospheric model for metal ion dynamics, which incorporates electric fields and winds from a whole atmospheric model. We revealed the time-dependent three-dimensional MIFs in the polar ionosphere, driven by two-cell convective electric fields. The simulated MIFs closely matched observations reported in previous studies and were primarily caused by electric fields. For example, metal ions gather in the evening cell rather than the morning cell in the ionospheric F region owing to the morning divergence and evening convergence electric fields; the narrow latitudinal metal ion concentrations appear in the pre-midnight ionospheric E region owing to downward motions and vertical convergence of ions by electric fields. Our findings emphasize the critical role of electric fields in polar metal ion dynamics and provide valuable insights for interpreting past and future MIF observations in the polar ionosphere
Structural organization of the Lorraine coal basin and formation of the Alsting thrust fold
No full textThe Lorraine Coal Basin (LCB), filled with continental clastic formations of the Upper Carboniferous-Permian age, developed along the Metz-Hunsrück-Fault-Zone (MHFZ). Despite the structural studies, the structure of the basement which control the total sedimentary thickness variations, and the Alsting fold structure and formation remains poorly constrained. In this study, the analysis of gravity data has allowed to map the MHFZ and more regionally the top basement structures beneath the basin. The analysis of 2D seismic lines and well data analysis has allowed to constrain the structure and formation of the Alsting fold.
The top basement map highlights the presence of highs (−1, 5 km) and deeps (−6, 5 km) trending NE-SW, NNE-SSW to N-S and NW-SE. This structuration explains the global sedimentary thickness variation of the sedimentary series in place. The first vertical derivative of the Bouger anomaly suggests that the MHFZ is continuous throughout the LCB and the SNCB. Furthermore, seismic interpretations show that the Alsting fold is a thrust fold whose formation and post-compression erosion occurred during the Stephanian. After this deformation phase, subsidence and deposition restarted during the late Stephanian. This study highlights a different Stephanian geological history of the BHL compared with other basins of the same age due to its structural position
The two-step scenario of the Messinian Crisis (Clauzon
No full textMany papers refer in a revised way to the two-step scenario of the Messinian Crisis conceived by Clauzon et al. (1996
An
No full textContext. Dipping neutron star low-mass X-ray binaries (NS LMXBs) are systems that exhibit periodic drops in their X-ray light curves. These are thought to be caused by material at the impact point of the gas stream onto the accretion disk, the bulge. Dipping systems are observed at high inclination and provide exceptional opportunities to address important open questions about accretion disks, such as the physical properties of the bulge, and the connection between disk atmospheres and disk winds.
Aims. We characterize the accretion disk plasmas in the 21-hour-period NS LMXB 4U 1624–490 and performed a detailed spectral analysis of the material in the impact region.
Methods. We used four XMM-Newton EPIC pn observations that specifically targeted dips and probed the dipping activity on different timescales (i.e., consecutive orbits and ∼6 months). We used a time- and flux-resolved spectroscopic analysis to probe the structural properties of the bulge moving along the line of sight and its homogeneity, respectively.
Results. During dipping, the primary spectrum is modulated by an ionized (log ξ ∼ 3.4) absorber with a varying column density and covering factor, and a colder absorber. This suggests that the bulge is a multiphase and clumpy absorbing medium. From size-scale arguments, we estimate the number of clumps in the bulge to be > 7 × 103. A highly ionized disk atmosphere only becomes evident when different absorption phases are analyzed individually. We show that a physical picture of the bulge can be constructed, and we highlight that future research might reveal the dependence of its properties on the system parameters and determine whether the bulge might affect the dynamics of the accretion disk
Impact of magnetic field gradients on the development of the magneto-rotational instability
No full textContext. The magneto-rotational instability (MRI) plays a crucial role in accretion disk modelling, driving magnetohydrodynamic turbulence and facilitating enhanced angular momentum transport. Notably, MRI is believed to be pivotal in the development of large-scale poloidal magnetic fields during binary neutron star mergers. However, the few numerical simulations that start from weak seed magnetic fields and capture its growth until saturation show the effects of small-scale turbulence and winding but lack convincing evidence of MRI activity.
Aims. We investigated how the axisymmetric MRI is impacted by magnetic fields with the realistic, complex topologies of the post-merger phase, where field gradients cannot be neglected. This analysis aims to improve our understanding of the conditions under which MRI develops in more realistic astrophysical scenarios.
Methods. We performed a linear analysis of axisymmetric MRI under these extended conditions and studied the resulting generalized dispersion relation. After deriving the extended MRI criteria, we first applied them to simple analytical disk models. Finally, we analysed the results obtained from a numerical relativity simulation of a long-lived neutron star merger remnant.
Results. We find that radial magnetic field gradients can significantly impact the instability, slowing it and suppressing it entirely if sufficiently large. Specifically, we derived modified expressions for the growth rate and wavelength of the fastest-growing mode. Evaluating them in the context of binary neutron star merger remnants, we find that conditions that potentially allow the instability to be active and grow on short enough timescales might be reached only in small portions of the post-merger remnant, and only at late times, t ≳ 100 ms after the merger.
Conclusions. Our results indicate that the role of the axisymmetric MRI in amplifying the poloidal magnetic field in the post-merger environment during the first (100) ms is likely limited
Strengthening Indonesia’s role in the ASEAN blue economy through policy and roadmap alignment
No full textIndonesia's expansive maritime domain and geostrategic position in Southeast Asia underscore its critical role in advancing sustainable ocean governance through the blue economy paradigm. This study examines the alignment between Indonesia's Blue Economy Roadmap (2023-2045) and the ASEAN Blue Economy Framework (2023), intending to assess policy coherence, institutional coordination, and implementation synergies at both national and regional levels. Employing a descriptive qualitative methodology and a meta-synthesis of policy documents, institutional reports, and scholarly literature. The analysis evaluates four dimensions of alignment: vision and objectives, institutional arrangements, implementation mechanisms, and stakeholder engagement. The findings demonstrate substantial convergence in sustainability-oriented priorities, inclusive economic growth, and ecosystem stewardship, particularly across five strategic pillars: blue bioeconomy, blue financing, ecosystem restoration, governance coordination, and marine data systems. Both frameworks articulate a shared commitment to integrating ecological resilience with economic transformation. Nonetheless, persistent challenges remain, including fragmented marine data management, limited inter-ministerial coordination, and insufficient mechanisms for local community participation. By strategically aligning its national roadmap with regional priorities, Indonesia can catalyze cohesive and resilient maritime governance. More broadly, the study contributes to the literature on regional ocean governance by positioning ASEAN as a potential global exemplar of sustainable and inclusive blue economic transformation
Passing and shooting accuracy in handball among Makassar city athletes
No full textThis study discusses passing and shooting, two key skills that determine the effectiveness of attacks and goal-scoring opportunities in handball. This study aims to (1) map the level of passing and shooting accuracy in handball athletes in Makassar City, (2) compare the accuracy profiles of both. The research method used is descriptive quantitative with 20 active athletes as a sample. Measurements using the Passing Accuracy Test and Shooting Accuracy Test refer to the IHF coaching guidelines and the "Teaching Handball" (IHF) textbook which contains standard dimensions, targets, and drill organization. The results show an average passing accuracy of 78.5% (good category) and shooting 69.2% (sufficient category). This pattern is consistent with the performance analysis literature which reports that winning teams generally have higher shooting efficiency and that shooting requires a more complex integration of biomechanical, tactical, and decision-making demands under pressure than passing. Practical recommendations include progressing pressure shooting training, varying shooting angles/positions, specific reinforcement, and integrating simple analytics (shot charts and pass maps) for daily feedback