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The Baribis Fault is an important active fault in West Java, Indonesia. This fault has recently attracted the attention of many parties since some fault segments pass through densely populated areas, raising the risk of shallow earthquakes. The long-offset resistivity tomography method was applied to image the active Baribis Faults. This method clearly showed the subsurface geometry, including the contact characteristics of the Baribis Fault near the subsurface. The long-offset resistivity tomography surveys were acquired using multi-electrodes and multi-nodes, and the data acquisition was wirelessly controlled via a WiFi connection. The pole–dipole resistivity tomography image shows a 35^∘ dip overhang structure of the Baribis thrust fault near the Jatigede area in Middle Eastern West Java, with a strike fault segment in a relative East–West direction. However, the other long-offset tomography images in northeastern West Java, near the Conggeang–Sumedang area, show the oblique thrust fault phenomena of the Baribis Fault with a strike in the Northeast–Southwest direction. The stress caused by the Cimandiri–Lembang regional strike–slip fault likely influences the dynamics of the Baribis Fault in the close area of Sumedang.

The formation mechanism of the fused porphyrin (CTPPH-NF) involves a rotation of the N(2) pyrrole ring of 2-aza-21-carba-5,10,15,20-tetraarylporphyrin (CTPPH₂) which is subsequently followed by formation of the C(3)–N(24) bond to yield the macrocycle with the fused pyrrole tripentacyclic ring. To approach the problem of the relative stability of the prearranged transient species theoretical investigations have been performed applying density functional theory (DFT). The molecular structures and electronic energy have been studied for idealized 2-aza-21-carbaporphyrin (CPPH₂) and porphyrin (PH₂) macrocycles created by a replacement of phenyl or other substituents with hydrogen or methyl groups. The following forms of 2-aza-21-carbaporphyrin and porphyrin were studied: CPH₂-I, 2-NH-CPH-I and PH₂-I in relation to CPH₂-P, 2-NH-CPH-P and PH₂-P, respectively (P indicates regular geometry (N(21) or C(21) located in the inner perimeter) and I indicates inverted geometry (N(21) or C(21) located in the outer perimeter).

A π delocalization exists through the inverted macrocycles: PH₂-I, CPH₂-I and 2-NH-CPH-I. The B3LYP/6-31G** optimized bond distances of I macrocycles reproduce the pattern of the P counterparts. The B3LYP/6-31G**//B3LYP/6-31G** calculated energy differences between the P and I structures are very similar for two considered 2-aza-21-carbaporphyrin tautomers: CPH₂-P → CPH₂-I, 18.50 kcal mol^-1, 2-NH-CPH-P → 2-NH-CPH-I, 17.55 kcal mol^-1; but essentially different for the regular porphyrin PH₂-P → PH₂-I, 45.56 kcal mol^-1. The methyl substitution at the 21-carbon or 5 and 20 meso positions preserved the order of stability as the calculated energy differences equal 21-CH₃-CPH₂-P → 21-CH₃-CPH₂-I, 13.39 kcal mol^-1; 5,20-CH₃-CPH₂-P → 5,20-CH₃-CPH₂-I, 17.87 kcal mol^-1.

Describing the lightest pseudoscalar mesons as bound states of quark and antiquark within the framework of an instantaneous Bethe–Salpeter formalism constructed such as to retain (in contrast to Salpeter’s equation) as much information on the relativistic effects provided by the full quark propagator as conceivable allows for a surprisingly simple implementation of their near masslessness mandatory for their interpretability as pseudo-Goldstone bosons related to the spontaneous breaking of the chiral symmetries of quantum chromodynamics.

Coastal grounding electrodes are currently an important means to alleviate land grounding electrode land constraints. In order to better invert the terrestrial geodesic resistivity in the coastal region, this paper proposes a complete set of inversion technology schemes. First, this paper proposes a layered land model for the coastal region, and a composite geodetic model is modeled by the fold junction of the land model and the ocean. Based on this, an adaptive subdivision boundary element method is proposed for solving the composite soil grounding calculation problem, and the accuracy and advantages of the method are demonstrated by examples. Finally, the paper uses the differential evolutionary algorithm to invert the exploration data of the four-point method in the coastal area, and obtains the parameters of the terrestrial layered geodetic model that meet the engineering requirements. The comparison with the grounding software CDEGS illustrates the effectiveness of the method. This paper carries out the research on the modeling and inversion methods of composite layered soil model, combining advanced numerical calculation methods and artificial intelligence algorithms to provide the support of computational tools for coastal resistivity inversion.

In this paper the classical and generalized numerical Rogers–Ramanujan continued fractions are extended to a polynomial continued fraction in one and two dimensions. Using the new continued fractions, the fundamental recurrence formulas and a fast algorithm, based on matrix formulations, are given for the computation of their transfer functions. The presented matrix formulations can provide a new perspective to the analysis and design of Ladder-continued fraction filters in one and two dimensions signal processing. The simplicity and efficiency of the presented algorithms are illustrated by step-by-step examples.

The problem of recovering the initial temperature of a body from discrete temperature measurements made at later times is studied. While this problem has a general formulation, the results of this paper are only given in the simplest setting of a finite (one-dimensional), constant coefficient, linear rod. It is shown that with a judicious placement of a thermometer on this rod, the initial temperature profile of the rod can be completely determined by later time measurements. The paper then studies the number of measurements that are needed to recover the initial profile to a prescribed accuracy and provides an optimal reconstruction algorithm under the assumption that the initial profile is in a Sobolev class.

To extract the intrinsic bottom back-scattering information from the reverberation data in shallow water has been a challenge topic for long time. It is shown that the modal back-scattering matrix (MBSM) is the intrinsic description of the bottom scattering.¹ The optimum source-depth distribution for inverting MBSM from the reverberation data has been discussed with a Pekeris waveguide.² In the present work, we extend the procedure to the general case of non-Pekeris waveguide by using the simulated annealing (SA) approach. Numerical simulated examples on searching the optimum source-depth distribution for MBSM inversion are presented. It is shown that: (1) the SA is an effective approach for searching the optimum source-depth distribution for MBSM inversion (2) the MBSM inverted from the optimal source-depth distribution has the strong stability against noise.

An algorithm that provides direct, efficient ND polynomial factorization is presented to solve the numerical issues that arise during the direct inversion of helium atom scattering (HAS) diffraction spectra. For an n-variate polynomial the algorithm directly deflates the polynomial to n-single variable equations by evaluating the ratio of pairs of polynomial coefficients. Error estimation of the coefficients of the 1D polynomials is then performed automatically using standard 1D search techniques. The effectiveness of the technique is demonstrated against bi- and trivariate polynomials and an approximate range of validity for error prone polynomials is demonstrated. To demonstrate the effectiveness of the technique, HAS diffraction spectra for the low coverage (2 × 1)-H/Pd(311) system have been analyzed using direct inversion and have revealed that H binds in a three-fold hollow site.

Configural processing is considered to be the hallmark of face expertise, which has been widely investigated by face global inversion (inversion effect) and local inversion (Thatcher effect). Using a passive detection task in which face stimuli are task-irrelevant, both the face inversion effect and the Thatcher effect on race perception of faces were investigated. We found that although the N170 inversion effect (enhanced and delayed N170 for inverted than upright condition) was similar across races of faces, Chinese participants showed a larger N170 Thatcher effect (enhanced N170 to Thatcherized faces than normal faces) for Mongoloid faces. The present data indicates the perceptual advantage of configural changes for in-group than out-group faces.

In this paper, we propose a novel integral transform coined as quaternion quadratic-phase wavelet transform (QQPWLT) by invoking the elegant convolution structure associated with the quaternion quadratic-phase Fourier transform. First, we explore some mathematical properties of the QQPWLT, including the orthogonality relation, inversion formula, reproducing kernel and some notable inequalities. Second, we study Heisenberg’s uncertainty principles and the logarithmic uncertainty principle associated with the quadratic-phase wavelet transform in quaternion domain. We culminate our investigation by presenting some illustrative examples.

A simple rigid precursor termed as a “diheterole” bearing thiophene linked to $\alpha$-pyrrole at 4-position was prepared using a three-step synthetic strategy. This functionalized diheterole was allowed to undergo acid-catalyzed condensation in the presence of Lewis acid (BF₃$·$ Et₂O) to produce the [2+2+2] cyclotrimer 1 as a major product with trace formation of 2and higher homologues.Various 1D and 2D NMR analyses along with theoretical investigations indicate that the molecule 1 exhibits nonaromaticity due to its non-conjugated annulenic structure. The optical properties and electronic structures were analyzed using UV-vis absorption spectroscopy and time-dependent density functional theory calculations. Detailed structural analyses revealed that the conformationally rigid triply S-confused hexaphyrin 1 adopts nearly planar geometry with three thiophene rings inverted. Upon protonation, the individual rings are tilted largely due to the steric congestion by both $\beta$-CH’s and pyrrolic NH’s inside the core. The calculated NICS(0) values of +1.73 ppm for the protonated species, 1$·$3H${}^{+}$ indicates the distinct non-aromatic feature as observed in 1 (NICS value of +2.34 ppm).

We investigated chirality transfer processes with two amide-linked zinc bisporphyrinates as hosts and chiral amino acid esters as guests. The linkers in these hosts contain a coordination site (pyridyl nitrogen or amino nitrogen). CD spectra were measured after titration of these zinc bisporphyrinates with amino acid esters. The CD spectra show that the signals were inverted during the titration. This result suggests that there is a two-step chirality induction process, which is most likely dominated by the corresponding 1:1 and 1:2 host-guest complexes. In the 1:1 complexes, the pyridyl nitrogen or amino nitrogen in the linkers is coordinated with zinc. NMR spectra confirmed such coordination interactions. Theoretical calculations also confirmed the corresponding chirality induction and inversion. This work provides a useful strategy to tune chirality transfer processes by introducing an extra coordination site in the linker.

Damage to buried pipelines due to complex ground responses has been reported at residential development sites and valley plains with complex ground structures. Three-dimensional (3D) ground amplification analyses using 3D, nonlinear, finite-element methods may be effective in predicting such damage; however, it is often difficult to construct ground structures that are capable of reproducing observational characteristics. In this paper, we propose a 3D ground structure optimization method using a 3000$\times$ forward finite-element dynamic analysis with approximately 0.27 million degrees of freedom, enabled by combining an automated 3D finite-element model-generation method and a fast 3D finite-element wave propagation analysis method. This optimization method is capable of estimating 3D ground structure models that can reproduce observational data characteristics. The effectiveness of the method is shown through an illustrative example.

Due to the limitation of seismic station coverage or the network transport interrupted when the earthquake occurred, an accurate seismic shakemap may not be released to the public quickly. When the near-source observed waveforms for the intensity prediction technology used are incomplete, we synthesize the seismic waveform into observation waveforms. An accurate seismic rupture process is necessary to synthesize virtual station observations. So, we should release the rupture process as soon as possible after a large earthquake. Most large earthquakes occur at the junction of two or three tectonic terranes. With violent tectonic movements, fault basins and uplift zones are distributed on the edge of the plateau. With complex structural conditions, the 1D layered half-space velocity structure model could not meet the requirement of earthquake rupture process inversion. It takes much time to calculate 3D Green’s function with a 3D velocity model for the complete waveform inversion of the earthquake rupture process. To rapidly invert the rupture process as accurately as possible, according to the geological conditions of the station, we calculated several Green’s function libraries in advance. We extracted Green’s functions from these libraries for each site based on the sites’ coordinates once an earthquake occurs. The time we spend in extracting Green’s functions from several Green libraries equals that we spend in extracting Green’s functions from one single library. The applicability of this method was tested in the 2017 Jiuzhaigou M6.5 earthquake with complex structural conditions in the mountain uplift zone. With our model, the time we spent in calculating the rupture process was almost the same as that we spent with the 1D velocity structure model, which was far less than that we could have spent in calculating 3D Green’s function. The degree of fitting between the synthetic data and the observation data of our model was much higher than the fitting of the 1D velocity model, which means that the earthquake rupture process we determined was more reliable.

The rupture process of large earthquakes is generally complex and contains multiple sub-faults planes with different focal mechanisms. The focal mechanisms inversion of these sub-faults by applying the Multi-Point-Source Faulting Representations (MPSFR) are essential for seismic stress analysis and earthquake disaster assessment. The MPSFR method is time-consuming and often with unstable results. In this study, we develop an Image Segmentation and Iterative Inversion (ISII) approach to calculate the MPSFR for large earthquakes by inverting near-field strong motion data. This new approach analyzes the rupture image of the earthquake and divides the entire rupture surface into several sub-rupture segments as a point source in the MPSFR. We approach the ISII model to the 2010 El-Mayor Cucapah (EMC) earthquake and the 2016 Kaikoura earthquake, respectively. In the EMC earthquake, the overall misfit was reduced from 0.58 (earthquake rupture model with the same focal mechanism) to 0.47 (IISI model with four different focal mechanisms). In the Kaikoura earthquake, the overall misfit was reduced from 0.67 to 0.55. The rupture process inverted by the ISII model is consistent with the joint multi-method inversion and the operation process is high efficiency. The test results indicate the ISII model can accurately and quickly invert the complex earthquakes rupture process and provide valuable information for earthquake disaster assessment.

The study of seismic ruptures is crucial for understanding major earthquake events. Historically, research on large earthquake rupture processes has required a long time to be published. However, recent advancements in earthquake early warning (EEW) systems have allowed for more rapid analyses of earthquake rupture inversions. The widespread and dense distribution of EEW stations provides in China an opportunity to study and invert rupture processes in near-real time. Two notable earthquakes were studied using this technology: the 2017 Jiuzhaigou MW 6.5 earthquake in Sichuan Province, China, and the 2022 Menyuan MW 6.7 earthquake in Qinghai Province, China. In both instances, numerous strong-motion sensors captured the seismic events and transmitted waveform data to data analysis centers in real time. Following automated site selection and preparation procedures, the rupture processes of these earthquakes were analyzed and released within 30min of the event origin. This rapid response time demonstrates that the seismic rupture process determined through inversion using existing EEW systems can serve as a guide for emergency rescue work after earthquakes.

Many models of genome rearrangement involve operations that are self-inverse, and hence generate a group acting on the space of genomes. This gives a correspondence between genome arrangements and the elements of a group, and consequently, between evolutionary paths and walks on the Cayley graph. Many common methods for phylogenetic reconstruction rely on calculating the minimal distance between two genomes; this omits much of the other information available from the Cayley graph. In this paper, we begin an exploration of some of this additional information, in particular describing the phylogeny as a Steiner tree within the Cayley graph, and exploring the “interval” between two genomes. While motivated by problems in systematic biology, many of these ideas are of independent group-theoretic interest.

Single-bond rotations or pyramidal inversions tend to either hide or expose relative energies that exist for atoms with nonbonding lone-pair electrons. Availability of lone-pair electrons depends on overall molecular electron distributions and differences in the immediate polarity of the surrounding pico/nanoenvironment. Stereochemistry three-dimensional aspects of molecules provide insight into conformations through single-bond rotations with associated lone-pair electrons on oxygen atoms in addition to pyramidal inversions with nitrogen atoms. When electrons are protected, potential energy is sheltered toward an energy minimum value to compatibilize molecularly with nonpolar environments. When electrons are exposed, maximum energy is available toward polar environment interactions. Computational conformational analysis software calculated energy profiles that exist during specific oxygen ether single-bond rotations with easy-to-visualize three-dimensional models for the trichlorinated bisaromatic ether triclosan antimicrobial polymer additive. As shown, fluctuating alternating bond rotations can produce complex interactions between molecules to provide entanglement strength for polymer toughness or alternatively disrupt weak secondary bonds of attraction to lower resin viscosity for new additive properties with nonpolar triclosan as a hydrophobic toughening/wetting agent. Further, bond rotations involving lone-pair electrons by a molecule at a nonpolar-hydrocarbon-membrane/polar-biologic-fluid interface might become sufficiently unstable to provide free mechanomolecular energies to disrupt weaker microbial membranes, for membrane transport of molecules into cells, provide cell signaling/recognition/defense and also generate enzyme mixing to speed reactions.

Frequency channelization is a fundamental signal processing operation employed across various domains, including communications and radio astronomy. The polyphase filterbank (PFB) represents an efficient and versatile means of channelization. When strict constraints are placed on the allowable spectral leakage between neighboring channels, an oversampled PFB design is advantageous. A helpful consequence of the oversampling is that inversion of the PFB to recover high temporal resolution is simplified and can be accomplished accurately using Fourier transforms. We describe this inversion approach and identify key design considerations. We examine the residual error and spectral/temporal leakage behavior when a channelizer and its corresponding inverter are cascaded, concluding that near-perfect reconstruction can be approached with appropriate selection of PFB and inverter design parameters.

Sea-surface wind agitation can be considered the dominant noise sources whose intensity relies on local wind speed during typhoon period. Noise source levels in previous researches may be unappreciated for all oceanic regions and should be corrected for modeling typhoon-generated ambient noise fields in deep ocean. This work describes the inversion of wind-driven noise source level based on a noise field model and experimental measurements, and the verification of the inverted noise source levels with experimental results during typhoon period. A method based on ray approach is presented for modeling underwater ambient noise fields generated by typhoons in deep ocean. Besides, acoustic field reciprocity is utilized to decrease the calculation amount in modeling ambient noise field. What is more, the depth dependence and the vertical directionality of noise field based on the modeling method and the Holland typhoon model are evaluated and analyzed in deep ocean. Furthermore, typhoons named “Soulik” in 2013 and “Nida” in 2016 passed by the receivers deployed in the western Pacific (WP) and the South China Sea (SCS). Variations in sound speed profile, bathymetry, and the related oceanic meteorological parameters are analyzed and taken into consideration for modeling noise field. Boundary constraint simulated annealing (SA) method is utilized to invert the three parameters of noise source levels and to minimize the objective function value. The prediction results with the inverted noise source levels exhibit good agreement with the measured experiment data and are compared with predicted results with other noise sources levels derived in previous researches.