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The primary goal of the current work is to investigate how wave propagation influences the performance of surface acoustics wave (SAW) macro- and nano-sensors. Therefore, shear horizontal (SH) waves use the surface piezoelectricity theory to explore SH waves in an orthotropic piezoelectric quasicrystal (PQC) layer overlying an elastic framework (Model I), a piezoelectric substrate, and an orthotropic PQC substrate (model II). This study employs a variable-separable technique. The theoretical forms are constructed and used to present the wavenumber of surface waves in any direction of the piezoelectric medium, based on the differential equations and matrix formulation. In addition, we take into account the surface elasticity theory in order to obtain the phase velocity equation. Two configurations are examined: an orthotropic piezoelectric material layer over an elastic framework and a piezoelectric material half-space with a nanosubstrate. Analytical expressions for frequency equations are derived for both symmetric and antisymmetric waves. This study investigates the effects of surface elastic constants, surface density, anisotropic piezoelectric constant, and symmetric and antisymmetric modes on phase velocity. This study is confined to only linear wave propagation. Additionally, the analysis is based on idealized material properties, surface properties, and characteristic length of the material. [ABSTRACT FROM AUTHOR]

The conventional automatic battery equalizer is characterized by its low cost in batter management system. However, its effectiveness is limited by the absence of signal feedback, leading to inadequate self‐regulation and protection of the topology. In this paper, an equalizer with constant magnetizing current is proposed. By adjusting the duty cycle of the MOSFETs, the magnetizing current can be flexibly controlled, which greatly improves the equalization rate and safety. The topology has multiple modes such as cell to cell (C2C), cell to string (C2S), and string to string (S2S). A creative signal sampling method is designed to obtain the cell voltage and magnetizing current with few sensors. And a novel balancing strategy is proposed, which can achieve wonderful accuracy of equalization at any initial voltage distribution. [ABSTRACT FROM AUTHOR]

This paper deals with a scheduling problem arising at the tactical decision level in aeronautical assembly line. It has the structure of a challenging multi-mode resource-constrained project scheduling problem with incompatibility constraints, a resource leveling objective and also a large number of tasks. We first present a new event-based mixed-integer linear programming formulation and a standard constraint programming formulation of the problem. A large-neighborhood search approach based on the constraint programming model and tailored to the resource leveling objective is proposed. The approaches are tested and compared using industrial instances, yielding significant improvement compared to the heuristic currently used by the company. Moreover, the large-neighborhood search method significantly improves the method proposed in the literature on a related multi-mode resource investment problem when short CPU times are required. [ABSTRACT FROM AUTHOR]

Nowadays, the most successful applications of full‐waveform inversion (FWI) involve marine seismic data under acoustic approximations. Elastic FWI of land seismic data is still challenging in theory and practice. Here, we propose a full dispersion spectrum inversion method and apply it to seismic data acquired in West Antarctica. Inspired by the conventional surface wave dispersion curve inversion method, we propose to invert the surface wave dispersion spectrum instead of the complicated waveforms. We compare the frequency‐velocity, frequency‐slowness, and frequency‐wavenumber spectra in terms of their ability to resolve dispersion modes and the feasibility of their adjoint updates and conclude that the frequency‐slowness spectrum is the best for our inversion objectives. We test four objective functions, subtraction, zero‐lag crosscorrelation, optimal transport, and the local‐crosscorrelation to quantify the spectrum mismatch and provide the corresponding adjoint source. We then theoretically analyze the convexity of the proposed objective functions and examine their convergence behavior using numerical examples. We also compare the proposed method with the classic FWI method and the traditional surface wave dispersion curve inversion method and discuss the strengths and weaknesses of each method. This technique is employed to evaluate the shallow velocity structures beneath a seismic array stationed in West Antarctica. Our proposed inversion scheme is also useful for more general applications such as imaging the shallow subsurface of the critical zones, like geothermal reservoirs, and CO2 storage sites. Plain Language Summary: Seismic full‐waveform inversion (FWI) is a cutting‐edge inversion method used for uncovering the Earth's subsurface structure. With the growing interest in clean energy and CO2 sequestration, exploring the subsurface in land is becoming crucial. However, there are only a few success stories of seismic FWI applied to land data mainly because of the complexity of the near‐surface and the increased nonlinearity of the problem. Here, we propose a full dispersion spectrum inversion method that seeks optimal velocity models in the subsurface by matching the seismic dispersion spectra. Dispersion spectra are the skeleton of seismic surface waves, which are simpler to quantify yet retain the key dispersion information of surface waves. It is generally easier for humans, as well as algorithms, to match simplified representations of the observed and simulated data, such as the dispersion spectrum, instead of the seismic waveforms themselves. The proposed method expands conventional 1D dispersion curve inversion to multiple dimensions and is accomplished under the framework of FWI. The proposed inversion method applies to seismic imaging applications in exploration and global seismology. Key Points: We propose a full dispersion spectrum inversion method for imaging the near‐surface and apply it to seismic array data collected in West AntarcticaThe surface wave frequency‐slowness spectrum is preferred over the frequency‐velocity and the frequency‐wavenumber spectra to measure the misfit in the proposed inversionThe optimal transport objective function is immune to cycle skipping but has a lower model resolution [ABSTRACT FROM AUTHOR]

In this study, the possibility of enhanced transverse magneto-optical Kerr effect (TMOKE) and performance monitoring of a hybrid nanostructure developed by sandwiching a ferromagnetic film within a gold layer and square periodic nanorod arrays, is theoretically investigated. Based on the findings, the TMOKE signal can be enhanced approximately 33 times when compared to the referenced planar film, which is elucidated by the hybrid of modes in the magnetic film region. In addition, a high level of environmental sensor performance is simultaneously achieved by recording the wavelength resonance positions with the variation of refractive index, which is compatible with gaseous medium from 1 to 1.01, indicating that the structure of the proposal will have applications in environmental monitoring. [ABSTRACT FROM AUTHOR]

A new and explicit form of the multi-axial elastic potential for elastic soft materials is constructed by means of two invariants of the Hencky strain. The new elasticity model with this form can bypass coupling complexities and uncertainties usually involved in parameter identification. Namely, exact closed-form solutions of decoupled nature are obtainable for stress responses under multiple benchmark modes. Unlike usual solutions with numerous coupled parameters, such new solutions are independent of one another and, as such, data sets for multiple benchmark modes can be separately matched with mutually independent single-variable functions. A comparative study is presented between a few well-known models and the new model. Results show that predictions from the former agree well with uniaxial and biaxial data, as known in the literature, but would be at variance with data for the constrained stress response in the plane-strain extension. In contrast, predictions from the new model agree accurately with all data sets. Furthermore, exact solutions for the Poynting effect of freely twisted elastic thin-walled tube are obtained from the new model. [ABSTRACT FROM AUTHOR]

This paper addresses the problem of multiple manufacturing modes integrated into the cutting stock problem, based on a real-life application of the concrete pole manufacturing. The main aim is to propose, formulate and test this integrated problem, which can be applied to the construction industry and other contexts of multiple manufacturing modes with cutting processes. The motivation for this proposal is the construction industry, in which reinforced concrete structures can be reinforced by various combinations of one-dimensional steel bars of varying thicknesses and lengths. An integer programming mathematical formulation is proposed aiming to minimise the total cost and to meet a demand of final products with different possible configurations. A column generation procedure is used as the solution method together with a heuristic procedure to find an integer solution. Computational results were performed with practical instances in order to assess the value of the approach and with a set of random generated instances in order to explore the influence of parameters on the results. Some managerial insights are presented. [ABSTRACT FROM AUTHOR]

To study the electromagnetic scattering of tilt-rotor aircraft during multi-mode continuous flight, a dynamic simulation approach is presented. A time-varying mesh method is established to characterize the dynamic rotation and tilting of tilt-rotor aircraft. Shooting and bouncing rays and the uniform theory of diffraction are used to calculate the multi-mode radar cross-section (RCS). And the scattering mechanisms of tilt-rotor aircraft are investigated by extracting the micro-Doppler and inverse synthetic aperture radar images. The results show that the dynamic RCS of tilt-rotor aircraft in helicopter and airplane mode exhibits obvious periodicity, and the transition mode leads to a strong specular reflection on the rotor's upper surface, which increases the RCS with a maximum increase of about 36 dB. The maximum micro-Doppler shift has functional relationships with flight time, tilt speed, and wave incident direction. By analyzing the change patterns of maximum shift, the real-time flight state and mode can be identified. There are some significant scattering sources on the body of tilt-rotor aircraft that are distributed in a planar or point-like manner, and the importance of different scattering sources varies in different flight modes. The pre-studies on the key scattering areas can provide effective help for the stealth design of the target. [ABSTRACT FROM AUTHOR]

Based on the Generalized bracket, or Beris–Edwards, formalism of non-equilibrium thermodynamics, we recently proposed a new differential constitutive model for the rheological study of entangled polymer melts and solutions. It amended the shortcomings of a previous model that was too strict regarding the values of the convective constraint release parameter for the model not to violate the second law of thermodynamics, and it has been shown capable of predicting a transient stress undershoot (following the overshoot) at high shear rates. In this study, we wish to further examine this model's capability to predict the rheological response of industrial polymer systems by extending it to its multiple-mode version. The comparison with industrial rheological data (High-Density Polyethylene resins), which was based on comparison with experimental data available in (a) Small Amplitude Oscillatory shear, (b) start-up shear, and (c) start-up uniaxial elongation, was noted to be good. [ABSTRACT FROM AUTHOR]

Transition of firing modes via synapse is a crucial step in neural coding. The neuron/synapse-like circuits have been proposed to simulate neural behaviors and functions. Despite a few researches of the mimicking neuron inspired on Josephson junction, the dynamical explanation of neuron-like junction is still unclear. We explore the dynamics in the Josephson junction composed of capacitor, nonlinear resistor and supercurrent component. The biophysical mechanism of neuron-like excitability in the junction is further interpreted by using frequency-current curve and two-parameter bifurcation plane. We propose the coupled model with memristive synaptic connection between two junctions to replace the synaptic coupling and neurons bridged for information exchange. It is found that the multiple modes are induced and controlled by the memristive synapse with plasticity. Meanwhile, the firing states of the two junctions with memristive synapse become synchronized under the suitable choices of parameters. These could help in the development of brain-like system with the Josephson junctions and memristive devices. [ABSTRACT FROM AUTHOR]

In the field of writing center research there is a paucity of information regarding tutoring students with dyslexia. This comes as no surprise considering it is only in the last 50 years that there has been a conscious effort to include those who have exceptionalities in all areas of education. In addition to a lack of research and training there is another issue that arises with disclosing exceptionalities. Those studying dyslexia have found that students are hesitant to disclose their learning disability because of the stigma and feelings of differentiation from their peers (Brizee et al., 2012). The question then becomes how we prepare tutors so they may approach a diverse group of learners and feel they have the skills to work with any student without disclosing their disability. Part of implementing the Universal Design for Learning approach is preparing tutors to accommodate a range of learning disabilities, exceptionalities, and cultures. It is important for tutors to understand common characteristics of dyslexic writers and strategies for working with them. Effective strategies include repeating explicit instruction, emphasizing phonetics, and mind mapping/chunking information. This project is focused on helping secondary writing center tutors and faculty to feel they have enough knowledge about dyslexia to help students who choose not to disclose their disability and offer strategies that they may utilize when working with dyslexic students. Furthermore, this project affirms the importance of creating an equitable learning environment for all students who seek the support of a writing center. [ABSTRACT FROM AUTHOR]

This research introduces a stochastic version of the multi-mode resource-constrained project scheduling problem (MRCPSP) and its mathematical model. In addition, an efficient multi-start iterated local search (MS-ILS) algorithm, capable of solving the deterministic MRCPSP, is adapted to deal with the proposed stochastic version of the problem. For its deterministic version, the MRCPSP is an NP-hard optimization problem that has been widely studied. The problem deals with a trade-off between the amount of resources that each project activity requires and its duration. In the case of the proposed stochastic formulation, the execution times of the activities are uncertain. Benchmark instances of projects with 10, 20, 30, and 50 activities from well-known public libraries were adapted to create test instances. The adapted algorithm proved to be capable and efficient for solving the proposed stochastic problem. [ABSTRACT FROM AUTHOR]

Broad output force and speed ranges are highly desired for actuators to endow soft robots with high performance, thereby increasing the range of tasks they can accomplish. However, limited by their low structural stiffness and single actuation method, most of the existed soft actuators are still difficult to achieve a broad force and speed range with a relatively compact body structure. Here, we propose a pneumatic and tendon actuation coupled soft actuator (PTCSA) with multiple actuation modes, mainly composing of a multi-joint thermoplastic polyurethanes (TPU)-made skeleton sealed in a film sleeve. The TPU skeleton with certain structural stiffness combined with soft joints allows PTCSA to output small force and respond rapidly under pneumatic actuation, as well as output high force and flexibly regulate response speed under tendon actuation, therefore achieving a broad force and speed range with a compact structure. The multiple modes constructed from the two actuation methods with different force and speed properties can cover diverse application scenarios. To demonstrate its performance, PTCSA is further used to construct a soft robotic arm (with a maximum lifting speed of 198°/s and can easily lift a load of 200 g), an inchworm-inspired wheel-footed soft robot (moves at a high speed of 2.13 cm/s when unload or pulls a load of 300 g forward), and a soft gripper (can grasp diverse objects, from 0.1 g potato chips to an 850 g roll of Sn-0.7Cu wire, from a high-speed moving tennis ball to an upright pen). This work indicates the potential of combining multiple complementary actuation methods to improve the force and speed range of soft actuators, and may provide inspiration for related research. [ABSTRACT FROM AUTHOR]

In this paper, we propose a Robust Breast Cancer Diagnostic System (RBCDS) based on multimode Magnetic Resonance (MR) images. Firstly, we design a four-mode convolutional neural network (FMS-PCNN) model to detect whether an image contains a tumor. The features of the images generated by different imaging modes are extracted and fused to form the basis of classification. This classification model utilizes both spatial pyramid pooling (SPP) and principal components analysis (PCA). SPP enables the network to process images of different sizes and avoids the loss due to image resizing. PCA can remove redundant information in the fused features of multi-sequence images. The best accuracy of this model achieves 94.6%. After that, we use our optimized U-Net (SU-Net) to segment the tumor from the entire image. The SU-Net achieves a mean dice coefficient (DC) value of 0.867. Finally, the performance of the system is analyzed to prove that this system is superior to the existing schemes.

• Tilting long period fiber grating sensor with multiple modes working simultaneously. • The sensor has a high liquid level sensitivity (8.78 nm/mm) and linearity (0.987). • is novel liquid level sensor has a temperature compensation function. This paper introduces a novel anti-temperature interference liquid level sensor constructed from a single tilt long-period fiber grating (TLPFG). The sensor achieves coupling between the core mode and high-order cladding modes via TLPFG excitation, leading to appearance simultaneously of two types of coupling peaks associated with low-order and high-order cladding modes in the transmission spectrum. Because these two types of coupling peaks exhibit different sensitivities to liquid level and temperature, simultaneous measurement of both parameters can be realized. Based on fiber grating coupled-mode theory, the grating period of TLPFG is designed to bring out three available coupling peaks, which are double resonance peaks from coupling of the core mode with the first-order 21st cladding mode, and a single resonance peak from coupling of the core mode with the second-order 20th cladding mode. Subsequently, optimization design is conducted for the grating tilt angle and grating length to ensure lower transmittance for all resonance peaks in the transmission spectrum. Furthermore, simulations and analyses are conducted to examine the relationship between the wavelength of the single peak, the wavelength spacing of the double peaks, and variations in both liquid level and temperature. The results show that within a liquid level variation of 16 mm, the liquid level sensitivities corresponding to the double peak spacing and single peak resonance wavelength are 8.26 nm/mm and −0.47 nm/mm, respectively. Similarly, within a temperature range of 20 to 80 °C, the temperature sensitivities corresponding to the double peak spacing and single peak resonance wavelength are −0.173 nm/°C and 0.046 nm/°C, respectively. Furthermore, by establishing a measurement inversion matrix, simultaneous measurement of liquid level and temperature can be achieved, enabling high-precision liquid level detection resistant to temperature interference. In comparison with other liquid level sensors, the sensor proposed in this paper has advantages including high sensitivity, high linearity, high accuracy, and simple structure, suggesting promising prospects in the domain of high-precision liquid sensing. [ABSTRACT FROM AUTHOR]

Copyright of Control Theory & Applications / Kongzhi Lilun Yu Yinyong is the property of Editorial Department of Control Theory & Applications and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The existing inertia estimation based on electromechanical oscillation relies on a single mode, which is limited in complex systems. In this letter, the inertia is estimated without worrying about the number of modes in the oscillation. The inertia expression is derived based on the swing equation in the frequency domain, which considers the mode coupling in the electromechanical bandwidth using a summation calculation. The effectiveness of the proposed inertia estimation method is validated through simulation data and real measurements. [ABSTRACT FROM AUTHOR]

Ultrahigh-frequency surface acoustic wave (SAW) devices with high quality ($Q$) factors are essential components for the next-generation wireless communication system. In this work, we reported high-performance and ultrahigh-frequency SAW devices with single-crystalline LiTaO3/SiO2/Si [LT-on-insulator (LTOI)] multilayered heterostructure. The fabricated SAW resonators exhibited multi-resonant modes (Rayleigh, Sezawa, and LLSAW mode) with the frequency ranging from 1.81 to 8.33 GHz. Especially, the SAW resonator with the Rayleigh wave frequency over 5.0 GHz and high $Q$ value around 2300 with a wavelength of 600 nm was realized. The variation of the phase velocity, the $Q$ factor for each resonant mode, and the effective coupling coefficients ($k^{2}_{\mathrm {eff}}$) versus the normalized LiTaO3 film thickness were systematically investigated. The proposed high-frequency SAW based on LTOI multilayered heterostructure possesses the low temperature coefficient of frequency (TCF, −20 ppm/K). Furthermore, a high-performance SAW bandpass filter with the center frequency of ~3.5 GHz was achieved. The work shows the great potential of the LiTaO3 single-crystalline thin-films-based SAW for ultrahigh frequency electronics applications. [ABSTRACT FROM AUTHOR]

The stability lobe diagram (SLD) is an important expression way of milling stability prediction result. The SLD obtained by only selecting the most flexible mode fails to predict the chatter if the milling process is dominated by multiple modes. To reveal the relationship between the SLD with multiple modes and the SLDs corresponding to each single mode, this paper studies the construction mechanism of the SLD with multiple modes by using a time domain method. First, the milling dynamic model of the tool with multiple modes is established. Then, the numerical method based on the Newton-Cotes rules is used to solve the milling dynamic model with multiple modes whose solution is in the form of the SLD. It shows that the SLD with multiple modes can be approximated by using the lowest envelope of the SLDs corresponding to each single mode. Finally, two study cases are adopted to verify the construction mechanism of the SLD with multiple modes. To verify the correctness of the SLD with multiple modes, a series of milling tests are carried out. The experimental results agree with the simulation results, which mean the proposed time domain method can reveal the construction mechanism of the SLD with multiple modes. [ABSTRACT FROM AUTHOR]

Excitation of multiple acoustic wave modes on a single chip is beneficial to implement diversified acoustofluidic functions. Conventional acoustic wave devices made of bulk LiNbO 3 substrates generally generate few acoustic wave modes once the crystal-cut and electrode pattern are defined, limiting the realization of acoustofluidic diversity. In this paper, we demonstrated diversity of acoustofluidic behaviors using multiple modes of acoustic waves generated on piezoelectric-thin-film-coated aluminum sheets. Multiple acoustic wave modes were excited by varying the ratios between IDT pitch/wavelength and substrate thickness. Through systematic investigation of fluidic actuation behaviors and performances using these acoustic wave modes, we demonstrated fluidic actuation diversities using various acoustic wave modes and showed that the Rayleigh mode, pseudo-Rayleigh mode, and A 0 mode of Lamb wave generally have better fluidic actuation performance than those of Sezawa mode and higher-order modes of Lamb wave, providing guidance for high-performance acoustofluidic actuation platform design. Additionally, we demonstrated diversified particle patterning functions, either on two sides of acoustic wave device or on a glass sheet by coupling acoustic waves into the glass using the gel. The pattern formation mechanisms were investigated through finite element simulations of acoustic pressure fields under different experimental configurations.

In this paper a multi‐start iterated local search (MS‐ILS) algorithm is presented as a new and effective approach to solve the multi‐mode resource‐constrained project scheduling problem (MRCPSP). The MRCPSP is a well‐known project scheduling NP‐Hard optimization problem, in which there is a trade‐off between the duration of each project activity and the amount of resources they require to be completed. The proposed algorithm generates an initial solution, performs a local search to obtain a local optimum, subsequently, for a certain number of iterations, makes a perturbation to that local optimum and performs a new local search on the perturbed solution. This whole process then restarts with a different initial solution for a certain number of restarts. The algorithm was tested on benchmark instances of projects with 30, 50 and 100 activities from well‐known libraries. The obtained results were compared to recent benchmark results from the literature. The proposed algorithm outperforms other solution methods found in related literature for the largest tested instances (100 activities), while for smaller instances it shows to be quite competitive, in terms of the average deviation against known lower bounds. [ABSTRACT FROM AUTHOR]

The real-time detection of feeding composition content holds significant importance in process monitoring and control optimization in industrial systems. However, the current feeding composition content is obtained by manual assay, with low detection frequency and significant hysteresis. Moreover, due to adjustment in production plans and adaptation to market demand, multiple operation modes frequently exist in real processes, making it difficult for a single mode to adapt to the actual site. To address the above problems, firstly, a novel variable sliding window method incorporating the improved longest common subsequence (LCSS) is proposed to achieve steady-state detection and multimode recognition in industrial processes. Secondly, according to the characteristics of different modes, the corresponding layered data reconciliation and parameter estimation (LDRPE) models are built to reduce the errors of the measured data and estimate the unmeasurable data. Finally, an online estimation model of feeding composition content based on multimode LDRPE is designed for estimating the coke content in the mixtures. The effectiveness of the proposed method is verified by the application to a real industrial system. • A novel variable sliding window method incorporating the improved LCSS is proposed to achieve multimode recognition. • The multimode LDRPE based on the novel variable sliding window method is established. • An online estimation model of feeding composition content based on multimode LDRPE is proposed and verified. • The proposed method outperforms common methods in real-time estimation performance of feeding composition content. [ABSTRACT FROM AUTHOR]

In real-world environments, selecting the right contractor is an important issue which considerably influences completion time, total cost and quality of performing the project. This paper deals with the multi-mode resource constrained project scheduling problem (MRCPSP) and contractor selection (CS) in an integrated manner. In fact, each activity is assigned to a contractor, an execution mode is selected for each activity, and the start/finish times of activities are determined. This paper presents a bi-objective optimization model to deal with MRCPSP-CS, aiming to minimize the total cost and completion time of the project, simultaneously. Then, four multi-objective decision making (MODM) techniques are used to solve the proposed model. Since none of MODM techniques dominates other ones, Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) is used to assess the performance of MODM techniques, confirming that MCGP-U outranks other ones. Finally, the augmented ε -Constraint method is used to solve some test problems, and perform sensitivity analysis on the number of contractors. Sensitivity analyses show that by increasing the number of available contractors, the Pareto front is significantly improved, and the Number of Pareto-optimal Solutions (NPS) increases. This helps decision maker(s) make appropriate decisions in a more flexible manner. [ABSTRACT FROM AUTHOR]

Copyright of Electric Power Automation Equipment / Dianli Zidonghua Shebei is the property of Electric Power Automation Equipment Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The difficulties of traditional rigid/soft grippers in meeting the increasing performance expectations (e.g., high grasping adaptability and wide graspable objects range) of a single robotic gripper have given birth to numerous soft-rigid coupling grippers with promising performance. However, it is still hard for these hybrid grippers to adaptively grasp various objects with diverse fragilities intact, such as incense ash and orange, due to their limited contact stiffness adjustable range and compliance. To solve these challenging issues, herein, we propose a dual-modal hybrid gripper, whose fingers contain a detachable elastomer-coated flexible sheet that is restrained by a moving frame as a teardrop shape. The gripper's two modes switched by controlling the moving frame position can selectively highlight the low contact stiffness and excellent compliance of the teardrop-shaped flexible sheets and the high contact stiffness of the moving frames. Moreover, the contact stiffness of the teardrop-shaped sheets can be wide-range adjusted by online controlling the moving frame position and offline replacing the sheets with different thicknesses. The compliance of the teardrop-shaped sheets also proves to be excellent compared with an Ecoflex 10 fingertip with the same profile. Such a gripper with wide-range tunable contact stiffness and high compliance demonstrates excellent grasping adaptability (e.g., it can safely grasp several fragile strawberries with a maximum size difference of 18 mm, a strawberry with a left/right offset of 3 cm, and a strawberry in two different lying poses) and wide-range graspable objects (from 0.1 g super fragile cigarette ashes to 5.1 kg dumbbell).

Modern spaceborne synthetic aperture radar (SAR) features a capacity of multiple imaging modes. It comes with Earth-observation data archives consisting of SAR images acquired in various modes with different resolutions and coverage. In this context, in addition to using single-mode images for SAR interferometry (InSAR), exploiting images acquired in different imaging modes for InSAR can provide extra interferograms and, thus, favors the retrieval of interferometric information. The interferometric processing of multimode image pairs requires special considerations due to significant variations in the Doppler spectra. Conventionally, the InSAR technique only uses the spectral band common in both master and slave images, and the remaining band is discarded before interferogram formation. Therefore, conventional processing cannot make full use of the observed data, and the interferogram quality is limited by the common band spectra. In this article, by exploiting the conventionally discarded spectrum, we present a new interferometric phase retrieval method for multimode InSAR data to improve interferogram quality. To this end, first, we propose a linear model to characterize the interferometric phase of a multimode image pair based on image spectral relation. Second, we adopt a sparse recovery method to inverse the linear model for the retrieval of the interferometric phase. Finally, we present real-data experiments on TerraSAR-X staring spotlight to sliding spotlight interferometry and Sentinel-1 strip map to Terrain Observation by Progressive Scan (TOPS) interferometry to test the proposed method. The experiment results show that the proposed method can provide interferograms with reduced phase noise and defocusing effect for multimode InSAR. [ABSTRACT FROM AUTHOR]

In this paper, a flexible cascaded multilevel inverter is proposed with a wide operational range. The inverter can change its topology structure to operate in three modes by a bidirectional switch unit. The nine-level or five-level mode of the inverter is adopted to optimize the output waveform when the input power is low. To decrease power losses, the three-level mode of the inverter is adopted to reduce the number of active switch devices when the input power is high. The topology and modulation strategy of the proposed inverter are presented and analyzed. The total losses and current THD of the inverter are calculated. In addition, simulations and experiments are conducted. The obtained simulation and experimental results indicate the correctness and feasibility of the proposed inverter and its modulation strategy. [ABSTRACT FROM AUTHOR]

Impact dampers are usually used to suppress single mode resonance. The goal of this paper is to clarify the difference when the impact damper suppresses the resonances of different modes. A cantilever beam equipped with the impact damper is modeled. The elastic contact of the ball and the cantilever beam is described by using the Hertz contact model. The viscous damper between the ball and the cantilever beam is modeled to consume the vibrational energy of the cantilever beam. A piecewise ordinary differential-partial differential equation of the cantilever beam is established, including equations with and without the impact damper. The vibration responses of the cantilever beam with and without the impact damper are numerically calculated. The effects of the impact absorber parameters on the vibration reduction are examined. The results show that multiple resonance peaks of the cantilever beam can be effectively suppressed by the impact damper. Specifically, all resonance amplitudes can be reduced by a larger weight ball. Moreover, the impacting gap is very effective in suppressing the vibration of the cantilever beam. More importantly, there is an optimal impacting gap for each resonance mode of the cantilever beam, but the optimal gap for each mode is different. [ABSTRACT FROM AUTHOR]

This study proposes a compact plasmonic metal-insulator-metal pressure sensor comprising a bus waveguide and a resonator, including one horizontal slot and several stubs. We calculate the transmittance spectrum and the electromagnetic field distribution using the finite element method. When the resonator’s top layer undergoes pressure, the resonance wavelength redshifts with increasing deformation, and their relation is nearly linear. The designed pressure sensor possesses the merits of ultrahigh sensitivity, multiple modes, and a simple structure. The maximum sensitivity and resonance wavelength shift can achieve 592.44 nm/MPa and 364 nm, respectively, which are the highest values to our knowledge. The obtained sensitivity shows 23.32 times compared to the highest one reported in the literature. The modeled design paves a promising path for applications in the nanophotonic field.

Copyright of Ordnance Industry Automation is the property of Editorial Board for Ordnance Industry Automation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Distributed digital array radar (DDAR) can operate in multiple modes and perform multiple functions. Compared with traditional phased array radars, the performance advantages of DDAR are obvious in many aspects. One of them is that DDAR can form space mesh in a wide scope. This article proposes a new fast mesh forming method. Unlike traditional multiple beam forming, the authors’ algorithm can form a mesh along range and azimuth. First, the range profile is obtained based on fast Fourier transform. Second, the mesh forming is divided into several steps that are accomplished in polar formatted plane. Finally, the polar formatted result is transformed into Cartesian coordinates. The authors tested the method using RADBASE data, which shows that the authors’ algorithm has good performance.

Distributed digital array radar (DDAR) can operate in multiple modes and perform multiple functions. Compared with traditional phased array radars, the performance advantages of DDAR are obvious in many aspects. One of them is that DDAR can form space mesh in a wide scope. This article proposes a new fast mesh forming method. Unlike traditional multiple beam forming, the authors' algorithm can form a mesh along range and azimuth. First, the range profile is obtained based on fast Fourier transform. Second, the mesh forming is divided into several steps that are accomplished in polar formatted plane. Finally, the polar formatted result is transformed into Cartesian coordinates. The authors tested the method using RADBASE data, which shows that the authors' algorithm has good performance. [ABSTRACT FROM AUTHOR]

• The process damping and multiple mode shapes at tool-workpiece contact zone were considered simultaneously with a multi-mode model in four spatial dimensions. • The proposed model considering material removal could assemble the change in mass and stiffness quickly by using geometric judgment conditions, and then the IPW dynamics would be extracted. • Different kinds of frequencies under different dominant modes of milling tool or workpiece were identified and expounded. • The three-dimensional stability lobe diagram (SLD) with the proposed model could predict the stability accurately. Especially when the workpiece dominated the machining process, the comprehensive SLD considering material removal was closer to the experimental results. Reasonable machining parameters would be selected to avoid chatter vibration in the practical processing. As an unfavorable factor of machining process, chatter threatens the machined quality of workpiece, which determines the assembly and fatigue performance of the workpiece. During the interaction between machine tool and thin-walled workpiece, the process damping effect, multiple modes response and dynamic changes caused by the material removal of the in-process workpiece (IPW) will make the machining process more complicated and introduce great difficulties to dynamic modeling and performance prediction. In this paper, we considered the process damping determined by the indentation volume between flank face of milling tool and machined surface, and used multi-mode model to describe this behavior. In order to establish the assembled material removal model of the IPW dynamics with multiple modes, the structure dynamic modification (SDM) and finite element method (FEM) were combined together. The updated third-order full discretization method was applied to solve the dynamic equation in modal space. Then, the three-dimensional stability lobe diagrams (SLDs) with and without material removal along the tool path were obtained respectively by enveloping multiple modes of the IPW and milling tool together. Finally, the cutting tests were carried out. The experiments showed that the assembled model could predict the dynamics of IPW accurately, and the proposed stability analysis model was relatively close to experimental results. Besides, the modes of thin-walled workpiece with weak rigidity do not always play a dominant role in the process of machining. Although the material removal rate is limited by considering the multiple modes of the system, the processing quality can be ensured. [ABSTRACT FROM AUTHOR]

In this letter, a low-profile microstrip antenna is presented for wideband requirement for both −10 dB |S11| and 3 dB gain bandwidth. Multiple modes with partial apertures are introduced to broaden the bandwidth within a relatively low profile. The working mechanism of the proposed antenna is analyzed, and the designed antenna has an impedance bandwidth of 57.3% (from 2.94 to 5.3 GHz), covering the frequency bands of fifth generation between 3 and 5 GHz with dimensions of 1.29λ0 × 1.01λ0 × 0.044λ0, where λ0 is the free-space wavelength of 4 GHz. The antenna prototype is fabricated, and the measured results are in good agreement with the simulation ones. The measured average gain is 5.26 dBi, and the radiation patterns remain stable in the target band with low cross-polarization levels at both principle planes. [ABSTRACT FROM AUTHOR]

A model-based optimal control method for multiple resistive wall mode (RWM) feedback stabilization has been developed and tested in plasma experiments at the EXTRAP T2R reversed field pinch (RFP) device. The controller is designed to target issues that arise in connection with RWM magnetic feedback stabilization systems based on discrete control coil and sensor arrays in tokamak and reversed field pinch devices. Multi-mode control capabilities in these systems is limited due to coupling of modes induced by the control system. The coupling originates from the generation of side-band control field harmonics and from aliasing of multiple harmonics in the sensor measurements. These couplings naturally leads to a multiple-input, multiple-output (MIMO) control problem. A model based state space controller has been designed based on a relatively simple physics model of the RWM plasma response. The physics model, which is applicable for the high aspect ratio RFP, is the basis for Fourier decoupling of the MIMO control problem into a set of single-input, multiple-output (SIMO) systems using the discrete Fourier transform (DFT). The linear, time-invariant physics model allows for the design of a state space model with states representing physical quantities; in this case the Fourier harmonics of the radial field at the resistive wall. Since the states cannot be directly measured, a Kalman filter is used for estimation of the states from the aliased sensor array measurements. A linear–quadratic (LQ) optimal state controller has been implemented. Design parameters, such as the LQ control cost function state weights and the Kalman filter input error covariances have been used to optimize the control operation in various ways. The controller has enhanced multi-mode control capabilities compared to earlier designs. For example it allows the prioritizing of suppression of one of the multiple magnetic field Fourier harmonics produced by a given control current DFT component. The controller has been tested in plasma experiments at EXTRAP T2R device, utilizing a newly installed extended sensor array, and the enhanced capabilities for multiple RWM feedback stabilization has been demonstrated. • Optimal control strategy for feedback stabilization of the resistive wall mode. • Aimed at Tokamak and Reversed Field Pinch with arrays of control coils and sensors. • A model-based, state space control design addresses the multivariable control problem. • Implemented and tested in real time plasma experiments on the EXTRAP T2R device. • Enhanced capabilities for multimode control is demonstrated. [ABSTRACT FROM AUTHOR]

Mixed-mode surveys have been around since the late 1980s. In the past thirty years, major changes in technology and society influenced and changed data collection and survey methodology. However, in those years, mixed-mode strategies remained part of the daily survey practice, although the type of mix implemented followed the changes in technology and data collection methods. In this paper, I summarize the state of the art in traditional mixed-mode surveys and discuss implications for mixed device surveys.

The control of modern aeroengine noise poses great challenge to the design of acoustic liners, due to the existence of multiple higher-order modes over a very wide frequency range in acoustic nacelles. In order to meet the pressing demand, the straightforward impedance eduction method is further developed such that it can be applied to more general acoustic environment where there are both plane mode and higher-order modes incident upon a test liner. A novelty of the present method is using a diagonally mounted microphone array on the opposite wall of the test liner in a flow duct, thus the measured wall sound pressure simultaneously contains the information of the modes in both the axial and transverse directions. Then, the employment of Prony's method enables the realization of the full modal decomposition to the acoustic field in the flow duct. Numerical experiments simulating acoustic fields with a finite element model are conducted to investigate and validate the feasibility of the present method for both a small-scale and a large-scale flow ducts. Two ceramic tubular liners and a perforated liner are tested as specimens, whose impedance values to be educed are known a priori by means of existing impedance models. Random perturbation is added into the acoustic field data to simulate realistic noisy acoustic environments. The results show that the present method can educe the imposed impedance with a good accuracy when the liner specimens are subjected to the sound field composing of multiple incident modes including several transverse modes in both ducts. The frequency scope of the impedance eduction is considerably extended when compared with the methods restricted by the assumption of plane incident mode, with the upper frequency reaching up to 6.0 kHz and 5.0 kHz for the ducts, respectively. A parametric study indicates that the accuracy of impedance eduction can be promoted by increasing the signal-to-noise ratio and the number of microphones. [ABSTRACT FROM AUTHOR]