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With the acceleration of urbanization, high-rise residential buildings has become a significant aspect of urban living. However, while high-rise residential buildings provide much housing, they also bring significant energy consumption. To raise the energy utilization efficiency of high-rise residential buildings, reduce energy consumption, and achieve sustainable development, this study focuses on high-rise residential buildings in cold regions. Through methods such as parametric modeling, joint simulation of building performance, multi-objective optimization algorithms, and improved grey wolf optimization algorithms, multi-objective optimization experiments are conducted to achieve optimal energy-saving effects. The outcomes denote that the average energy consumption of buildings remains at around 20.5 kW h/m2, and the maximum value of the last generation thermal comfort solution set is maintained at 62%, while the minimum value is maintained at 58%. The improved grey wolf optimization algorithm reduces training time, has better predictive ability, and can more accurately characterize changes in energy consumption of high-rise buildings. This study provides practical design methods and strategy references for high-rise residential buildings in the design phase by analyzing data, mining patterns, and summarizing design strategies.

In this study, frozen red sandstone specimens were impacted by a Split Hopkinson bar (SHPB), with a velocity of 4.558 ∼ 6.823 ms −1 . The temperature of the specimens was maintained at −15 °C during the experiment. For comparison purposes, static uniaxial compression tests were conducted in advance using a freezing triaxial test machine. Four stress-strain curves were obtained in different average strain rates. The test results suggested that when the average strain rate is low, the specimen strength changes gradually; but when it is high, its strength changes rapidly. When the average strain rate is 120.73 s −1 , the peak value of stress is as high as 82.96 MPa, which is about two times that of the static compressive strength of 44.1 MPa. A constitutive model was established that was composed of the damaged, viscoelastic and spring bodies, and revealed the variations of compressive strength and strain for the frozen red sandstone under different high strain rates. The test results also showed that the failure form was correlated to the average strain rate of the frozen red sandstone. When the average strain rate is low, the damage was only distributed on the specimen’s edges. However, as the average strain rate increases, the damage range extended to the central parts of the specimen. When the average strain rate reached 107.34s −1 , the specimen was smashed.

The coherent control of phonon polaritons (PhPs) in holds transformative potential for nonlinear photonics. We demonstrate terahertz-driven excitation of low-frequency PhPs in zinc oxide (ZnO) crystals, with their nonlinear dynamics resolved via time-resolved second harmonic generation (SHG) spectroscopy. By achieving phase matching via nine sequential reflections within a millimeter-scale crystal, we observe sustained SHG oscillations with 3-4 THz modulation frequencies, achieving optimal extinction ratios of ~18 dB that persist for 90 picoseconds—a temporal span directly governed by polariton propagation dynamics. This work establishes a dual-functionality platform enabling spectral-temporal resolved mapping of quasiparticle interaction dynamics while simultaneously advancing polariton-engineered nonlinear optical modulators through symmetry-broken frequency conversion architectures. The authors demonstrate resonant excitation of phonon-polaritons based on THz-driven ZnO single crystals. This clarifies the generation mechanism of phonon-polaritons, enabling their observation for various nonlinear regimes.

Relativistic collisionless shocks, which are ubiquitous in the cosmos, play a significant role in various astrophysical phenomena such as gamma-ray bursts, PeVatrons, and supernova shock breakouts. Here we present a demonstration using a compact femtosecond laser system to generate sub-relativistic collisionless shocks (0.03 c ) under astrophysically relevant conditions. We attribute the shock formation to a rapidly growing Weibel instability in a precisely tuning low-density preplasma environment, which resembles the interstellar media near an astrophysical central engine. Owing to this Weibel instability, a 5000 Tesla magnetic field is developed within 2.7 ps, leading to the collisionless shock formation and subsequent breakout at the preplasma boundaries. This platform enables direct investigation of astrophysics related to relativistic collisionless shocks. The achieved parameters bridge the gap between astrophysical observations and controlled laboratory experiments, offering unprecedented opportunities to validate cosmic shock models. Collisionless shock waves at relativistic velocities are ubiquitous in the universe and lead to the generation of energetic ions and radiation. Here, the authors demonstrate the generation of subrelativistic collisionless shock of astrophysical relevance in the laboratory, by means of table-top femtosecond laser pulses focused onto solid targets.

Reaction pathways of biochemical processes are influenced by the dissipative electrostatic interaction of the reagents with solvent water molecules. The simulation of these interactions requires a parametrization of the permanent and induced dipole moments. However, the underlying molecular polarizability of water and its dependence on ions are partially unknown. Here, we apply intense terahertz pulses to liquid water, whose oscillations match the timescale of orientational relaxation. Using a combination of terahertz pump / optical probe experiments, molecular dynamics simulations, and a Langevin dynamics model, we demonstrate a transient orientation of their dipole moments, not possible by optical excitation. The resulting birefringence reveals that the polarizability of water is lower along its dipole moment than the average value perpendicular to it. This anisotropy, also observed in heavy water and alcohols, increases with the concentration of sodium iodide dissolved in water. Our results enable a more accurate parametrization and a benchmarking of existing and future water models. The intermolecular dynamics of liquid water impact most biological processes. Here, the authors use intense terahertz electromagnetic pulses to generate a transient, out-of-equilibrium state of the water network to show that the molecules become oriented and probe the polarizability of this anisotropic state.

In order to evaluate the influences of the topology design of a Halbach Magnet Array (HA) on the performance of a motor, a PMSM with an outer coreless rotor using a Halbach Magnet Array (HAORPMSM) is proposed in this article. The design parameters of the HA could be separated into dividing methods per pole, magnet thickness, and initial magnetization direction angle. The phase Back-EMF under constant mechanical speed is chosen as the index to measure the performance of the motor. To start with, different dividing methods of the HA are evaluated. After that, the influence of thickness considering the utilization of the magnet is studied. Lastly, the relationship between initial magnetization direction and motor manufacturing is represented. The results show that the HA design meets the optimized performance considering the balance of the amount of magnet usage and manufacturing when using specific HA parameters.

Multi-scale 3D geological modeling technology is a vital issue to illustrate the complex geological conditions of infrastructure projects at the regional scale, engineering scale, and outcrop scale. It is also the computational basis for numerical geotechnics and seepage stabilization studies. However, empirical interactive modeling methods based on expert knowledge are mostly applied in existing numerical researches and geological structures at different scales are modeled independently, which reduces the credibility of simulation. Therefore, this research states a 3D fusion modeling method of multi-scale geological structures: (1) The multi-constraint NURBS modeling method for multi-valued strata at regional scale and the discrete fracture network modeling method for discontinuities at outcrop scale are presented. (2) The subdivision-NURBS modeling method for multiple genera geological bodies at engineering scale is raised so that the genus characteristics of geological bodies can be expressed in an objective parameterized way rather than in an empirical interactive-modeling way. (3) The Enhanced Boolean Logic Sequences of Oriented Geological Interfaces (E-BLSOGI), where the multiple genera geological bodies at engineering scale and the discontinuities at outcrop scale are additionally introduced based on the BLSOGI method offered in authors’ previous study [1], is provided to achieve 3D fusion modeling of multi-scale geological structures. The practice indicates that the 3D fusion modeling of multi-scale geological structures is realized, evidencing that results without integrating multi-scale geological structures underestimate the compressive stress (16.37, 10.52, and 33.09%), tensile stress (16.57, 21.57, and 10.76%), and displacement (7.17, 47.62, and 33.62%) of the dam foundation in -, -, and z-, directions, respectively.

Achieving good performance in terms of a fast and accurate maximum torque per ampere (MTPA) control method depends on both accurate parameter estimation and a sophisticated control strategy. However, it often requires a complex and long computational process. This paper proposes an efficient control method using the relationship of torque and current angle for maximum torque per ampere control of the interior permanent magnet synchronous motor (IPMSM) for vehicle application. It was found that it is not necessary for the control method to determine the inductance in the d-q axes; the identification of the difference between each axis is enough. Furthermore, this paper presents a simple and effective procedure to estimate the difference in inductance online, where the linear iron loss calculation method is also designed to support the above process. The proposed control method was experimentally validated on a 5 kW prototype by a TMS320F28335 microcontroller and DSPACE synchronized with a personal computer. The results show that the control process has faster and more accurate performance than the conventional method.

Accurate localization of microseismic sources is essential in fields such as oil and gas extraction and underground energy storage. Current seismic source localization methods based on full waveform inversion exhibit a high degree of nonlinearity and involve complex gradient calculations for the objective function. However, data-driven neural network microseismic source localization methods lack physical constraints, which can compromise geological validity. To address these challenges, this paper proposes a microseismic source localization method that integrates full waveform inversion with a recurrent neural network. First, the seismic wavefield propagation operator is designed using convolutional kernels to achieve networked microseismic forward modeling. Next, chain differentiation of the neural network is employed to calculate the gradient for full waveform inversion in reverse, improving computational efficiency. Finally, by minimizing the error between the observed and forward-modeled data, the spatial components of the seismic source are optimized, and non-maximum suppression is applied to obtain the spatial location of the seismic source. The experimental results reveal that the proposed method achieves high localization accuracy, high computational efficiency, and resistance to noise.

In order to expand the application field of magnetic bearings, this article studies a novel radially isolated active magnetic bearing (IAMB) system in which the stator and the rotor are separated by a layer of metal isolation sleeve. Aimed at the shortcomings of existing modeling methods, a distributed magnetic circuit model (DMCM) was proposed based on the magnetic field segmentation theory for IAMBs. Considering material nonlinearity and leakage flux, the flux distributions of the isolation sleeve and air gap are calculated accurately. Finally, the 3D finite element model (3D FEM) and experimental platform were built to verify the feasibility of the IAMB and the correctness of the DMCM.