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The topological structure of a recursive interconnection network can be modeled by an n -dimensional graph G n. A faulty vertex set (resp. edge set) of G n is called a t -embedded vertex (resp. edge) cut if the remaining network is disconnected and each vertex in the residual network is in a copy of fault-free t -dimensional graph G t. The t -embedded vertex connectivity ζ t (G n) (resp. the t -embedded edge connectivity η t (G n)) is defined as the minimum cardinality over all t -embedded vertex (resp. edge) cuts of G n. The m -ary n -dimensional hypercube G (n , m) has an elegant recursive structure and is also a generalized variant of the classical hypercube. This paper studies the reliability of the G (n , m) and generalizes some known results in ternary n -cubes. Specifically, we prove that ζ t (G (n , m)) = (m − 1) (n − t) m t for t ≤ n − 2 and η t (G (n , m)) = (m − 1) (n − t) m t for t ≤ n − 1. [ABSTRACT FROM AUTHOR]

In this paper, we study the distribution of parallelograms and rhombi in a given set in the plane over arbitrary finite fields F q 2. As an application, we improve the recent result due to Fitzpatrick, Iosevich, McDonald, and Wyman on the Vapnik–Chervonenkis dimension of the induced distance graph. [ABSTRACT FROM AUTHOR]

The use of nanoparticles has significantly increased in many areas, such as biomedical research, being highly useful as nanoprobes for imaging and as nanocarriers for drug delivery applications. Nevertheless, this potential can only be achieved with the correct characterization of the nanoparticles, since their size and shape can directly affect their biological behavior. In this study, we propose a novel approach for a monolayer deposition of gold and platinum nanoparticles on Si substrates suitable for medium energy ion scattering (MEIS) analysis. The samples were prepared using poly(ethylene glycol) 6000 (PEG 6000) as a coating agent for the substrates, utilizing a spin coater-a versatile, cost-effective, and practical technique. The samples were first analyzed with the RBS technique to assess the adhesion and the overlapping of the nanoparticles in the substrates coated with PEG 6000 and then characterized through the MEIS technique. The analysis through MEIS allowed the determination of the shape, size, and coverage area of the nanoparticles. Scanning and transmission electron microscopy were also performed on the samples, with the results corroborating the findings of the MEIS experiment. Together, the data obtained with microscopy and the MEIS technique suggests the effectiveness of the method in the production of monolayer samples. [ABSTRACT FROM AUTHOR]

A current-limiting and consequent direct current (DC) arc interruption requires an increase in arc resistance r a r c for a DC fuse. Flattery silica (SiO2) sand has been used as an arc quenching medium in fuses for decades. However, there are few reports about a novel arc quenching medium which enables more r a r c increases compared to flattery SiO2 sand. This paper uniquely selected a novel arc quenching medium based on the following material properties: (1) electrical resistivity and thermal conductivity in the solid phase, (2) the possibility of r a r c increasing in the gas phase, (3) the possibility of electrical insulation after re-solidification, and (4) the cost of materials. As a result, we originally selected a powder mixture of silicon-nitride (Si3N4) and flattery SiO2 sand as a promising novel arc quenching medium. Therefore, DC interruption experiments were performed using a Si3N4/flattery SiO2 sand powder mixture under different Si3N4 concentration conditions. As a result of 1000 A DC arc quenching experiments, the utilization of Si3N4 powder with the flattery SiO2 sand successfully increased the arc resistance r a r c during the arc quenching process. The increasing Si3N4 concentration exhibited a further increase in r a r c during the arc quenching process. As a result of the r a r c increase, the arc quenching time was significantly shortened to 30 ms for 30 wt.% Si3N4 conditions from 54 ms for the SiO2 sand conditions. In addition, utilization of Si3N4 powder achieved high insulation resistance over few MΩ after DC arc interruption. The above results clearly indicate that utilization of Si3N4 powder with flattery SiO2 sand can increase the DC interruption performance of the fuse. [ABSTRACT FROM AUTHOR]

In this paper, the characteristics of a nanosecond spark discharge with a pin–pin electrode configuration have been systematically studied. Both a streak camera with high temporal resolution and an intensified charge-coupled device (ICCD) camera are employed together to investigate the breakdown and evolution process of the discharge. The formation of initial breakdown and mode transition from streamer to spark in the electrode gap are clearly observed on the time scale of several nanoseconds with a temporal resolution of 100 ps. In addition, the time-resolved spectra technology is also used to analyze the generation and quenching mechanisms of reactive species, the electron density, and the electron temperature. The results show that there is a 1.25 ns initial discharge breakdown and that a bright cathode spot exists before the transformation from streamer to spark channel. After a faster cathode filament and a slower anode filament propagate and merge at the electrode gap, the spark discharge phase begins. The generation processes of different reactive species depend on the discharge phase to a great extent. The N2* is first generated during the streamer phase while the O*, N*, and N+ are mainly generated under the spark phase, in which the electron temperature calculated by Boltzmann plots is 2.74 eV, and the electron density determined from the Stark broadening of O lines is on the order of 1016 cm−3. [ABSTRACT FROM AUTHOR]

An electromagnetic parameter-retrieval-based surrogate-assisted optimization (PSAO) algorithm is presented to reduce radar cross section (RCS) by optimizing the on-platform honeycomb absorbing structures. To facilitate the optimization process, the honeycomb structure is transformed to an anisotropic homogeneous slab, and the effective parameters of the slab are extracted by the retrieval algorithm. A multi-fidelity model is employed to reduce the computing-time consumption, in which a Gaussian process (GP) regression model is used as the substitute for the coarse model. The GP model establishes a relationship between the geometry of the honeycomb structure and the RCS response of the target coated with the equivalent slab. Finally, the optimization result of the fine model is achieved through a space mapping strategy. The accuracy of the parameter extraction algorithm is verified by analyzing the honeycomb absorbing structure. Subsequently, the proposed optimization method is applied to a metal plate and a metal cylinder, resulting in a 10 dB reduction of RCS in broadband and wide-angle scenarios. This demonstrates the applicability of the proposed PSAO algorithm to both planar and conformal on-platform honeycomb absorbing structures. Furthermore, an NACA0015 foil is analyzed, showing an average RCS reduction of 10 dB and a minimum RCS reduction of 5 dB in the X-band. These results indicate that the PSAO approach can effectively apply to complicated targets. Additionally, the proposed method exhibits significant advantages in terms of computational accuracy and efficiency compared to the traditional genetic algorithm. [ABSTRACT FROM AUTHOR]

• A WGM-FP hybrid microcavity for dual-parameter measurement is presented. • The two signal components could be well demodulated. • The crosstalk between concentration and temperature of NaCl solutions is reduced. Whispering gallery mode (WGM) resonator is sensitive to the external medium change due to its strong light-matter interaction. However, the temperature sensitivity of silica-based WGM resonators would cause crosstalk, which is a fatal shortcoming for those high-quality (Q) resonators. In this paper, a hybrid microcavity including WGM resonance and Fabry–Pérot (FP) interference is proposed for simultaneous measurement of NaCl concentration and temperature, using the same microcavity in the same system to obtain two types of optical signals. The experimental results indicate that the maximum measurement error of NaCl concentration and temperature without compensation is about ± 0.026 % and ± 1.1 °C, while they would be ± 0.012 % and ± 0.3 °C after compensation. Sharing one microcavity enables temperature compensation to achieve temperature synchronization, and sharing of one system ensures the simplicity and stability of the sensing platform. [ABSTRACT FROM AUTHOR]

Precisely controlled digital pulse plays a crucial role in various cutting-edge testing applications. This paper introduces an innovative approach to digital pulse generation utilizing an FPGA transceiver, with the AMD evaluation board ZCU102 serving as a demonstrative platform. In the normal mode, the transmitter generates a serial bit stream, enabling the generation of single or repeated pulses with configurable width and period. In the high precision mode, an internal dedicated phase interpolator enhances the configuration step size for width and period by up to 64 times, providing finer phase shift capability. The demonstration system operates at a line rate of 10 Gbps, achieving a resolution of 100 ps in normal mode and 1.5625 ps in high precision mode. This paper details the design methodology, presents test results for pulse width uncertainty and non-linearity, and showcases achieved period jitter and time interval error jitter as small as around 1 ps. • A novel digital pulse generator is implemented with GTH transceiver in AMD FPGA. • Transceiver can produce digital pulse by controlling the sent bits with low jitter. • Resolution can be further enhanced by phase interpolator in the transceiver. [ABSTRACT FROM AUTHOR]

• Nonuniform E-field is restored by measuring E-FISH signals along probing laser. • Convergence of inversion algorism related to measuring system parameter is given. • Accuracy of inversion algorism is validated via experimental investigations. • Robustness of inversion algorism in resisting measurement noise is confirmed. The electric field-induced second-harmonic generation (E-FISH) method can offer high spatiotemporal resolution in electric field measurement, but faces challenge in reconstructing the inhomogeneous electric field along the probing laser. This paper presents an inversion method to reconstruct the electric field profile by using E-FISH signals measured from multiple points along the probing laser. The relationship between the condition number of the inversion coefficient matrix and the parameters of E-FISH measurement system is clarified. The inversion method is validated through experimental investigations conducted in three different electrode configurations, namely the plate-to-plate gap, the rod-to-rod gap, and the rod-plate gap. With the inhomogeneity coefficient varies from 1 to 10.7, the maximum deviation between the measured electric field and the finite element simulation is less than 6%. This method does not rely on priori assumptions and electrode configurations, and exhibits good robustness in resisting the effect of measurement noise on the inversion accuracy. [ABSTRACT FROM AUTHOR]

NP3L (Non perspective-three-line) aims to estimate the poses of three cameras from three line correspondences, which can be applied into multi-camera systems for localization. Existing methods lack a deep insight for different line distributions, resulting in the inaccurate pose estimation. This paper focuses on the robust and accurate solution for different line distributions. First, for the general situation, an algebraic method is proposed to establish two intermediate coordinates to simplify the rotation matrix. Subsequently, a polynomial is constructed for rotation and translation estimation. Second, this paper divides line distributions into six categories. Based on the proposed method, a specific simplified edition is designed for each distribution. Third, this paper provides insightful analyses of the solution number, polynomial order, existences of closed-form solutions for all line distributions. In experiments, the comparative results verify that the proposed methods can estimate relatively accurate camera pose, and outperform state-of-the-art methods on the synthetic and real-world datasets. • Algebraic methods are proposed for NP3L problem in general and special distributions. • This paper analyzes the properties of the proposed methods for special distributions. • The proposed methods offer accuracy and precision compared to the state-of-the-arts. [ABSTRACT FROM AUTHOR]