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Coupled trajectory mixed quantum–classical (CTMQC) dynamics is a rigorous approach to trajectory-based non-adiabatic dynamics, which has recently seen an improvement to energy conservation via the introduction of the CTMQC-E algorithm. Despite this, the method's two key quantities distinguishing it from Ehrenfest dynamics, the modified Born–Oppenheimer momentum and the quantum momentum, require regularization procedures in certain circumstances. Such procedures in the latter can cause instabilities, leading to undesirable effects, such as energy drift and spurious population transfer, which is expected to become increasingly prevalent when the system gets larger as such events would happen more frequently. We propose a further modification to CTMQC-E, which includes a redefinition of the quantum momentum, CTMQC-EDI (double intercept), such that it has no formal divergences. We then show for Tully models I–III and the double arch model that the algorithm has greatly improved total energy conservation and negligible spurious population transfer at all times, in particular in regions of strong non-adiabatic coupling. CTMQC-EDI, therefore, shows promise as a numerically robust non-adiabatic dynamics technique that accounts for decoherence from first principles and that is scalable to large molecular systems and materials. [ABSTRACT FROM AUTHOR]

During tsunamis, the interaction between moving seawater and the Earth's magnetic field generates a magnetic field detectable by electromagnetic sensors located on land or on the seafloor. In this study, we introduce new methods for estimating tsunami propagation direction and horizontal velocity fields using tsunami magnetic field data. We derive a transfer function that establishes a relationship between the tsunami magnetic field and the velocity field, emphasizing the alignment between the horizontal magnetic field and the tsunami's propagation direction. This transfer function was validated with data from the 2009 Samoa and 2010 Chile tsunamis. Our findings show that tsunami horizontal velocities and directions can be accurately determined from these magnetic fields. This advancement enables the use of tsunami magnetic fields to provide comprehensive data for tsunami warning systems and to improve the inversion of tsunami seismic sources. This article is part of the theme issue 'Magnetometric remote sensing of Earth and planetary oceans'. [ABSTRACT FROM AUTHOR]

This study introduces the nonlinear inertial amplifier resilient friction bearing isolators (NIARFBI). Another friction base isolator, namely the nonlinear inertial amplifier friction pendulum system (NIAFPS), is derived by eliminating the static damping from the governing equation of motion of the NIARFBI. The damping for NIAFPS is generated through the motion of the friction element of the isolator during the movement of the base layer. These novel isolators are placed at the base of the multiple degrees of freedom (MDOF) systems to reduce their dynamic responses. Every element of the highly nonlinear governing equations of motion of the dynamic systems isolated by each nonlinear isolator is linearized using the stochastic linearization approach. The specific mathematical formulation for the optimal design parameters for each nonlinear isolator is derived using the H2 optimization approach. In order to determine the dynamic responses analytically, the transfer function is established. The dynamic responses of the novel isolators are compared with the dynamic responses of the traditional isolators. Accordingly, the displacement reduction capacities of optimum NIARFBI and NIAFPS are significantly 93.60% and 70.82%, superior to TRFBI and TFPS. The acceleration reduction capacities of optimum NIARFBI and NIAFPS are 88.27% and 58.92% superior to TRFBI and TFPS. The recently developed expressions for this study are all mathematically accurate and applicable for practical applications. [ABSTRACT FROM AUTHOR]

This paper explores the importance of the electric eel foraging optimization (EEFO) algorithm in addressing feature selection (FS) problems, with the aim of ameliorating the practical benefit of FS in real-world applications. The use of EEFO to solve FS problems props our goal of providing clean and useful datasets that provide robust effectiveness for use in classification and clustering tasks. High-dimensional feature selection problems (HFSPs) are more common nowadays yet intricate where they contain a large number of features. Hence, the vast number of features in them should be carefully selected in order to determine the optimal subset of features. As the basic EEFO algorithm experiences premature convergence, there is a need to enhance its global and local search capabilities when applied in the field of FS. In order to tackle such issues, a binary augmented EEFO (BAEEFO) algorithm was developed and proposed for HFSPs. The following strategies were integrated into the mathematical model of the original EEFO algorithm to create BAEEFO: (1) resting behavior with nonlinear coefficient; (2) weight coefficient and confidence effect in the hunting process; (3) spiral search strategy; and (4) Gaussian mutation and random perturbations when the algorithm update is stagnant. Experimental findings confirm the effectiveness of the proposed BAEEFO method on 23 HFSPs gathered from the UCI repository, recording up to a 10% accuracy increment over the basic BEEFO algorithm. In most test cases, BAEEFO outperformed its competitors in classification accuracy rates and outperformed BEEFO in 90% of the datasets used. Thereby, BAEEFO has demonstrated strong competitiveness in terms of fitness scores and classification accuracy. When compared to its competitors, BAEEFO produced superior reduction rates with the fewest number of features selected. The findings in this research underscore the critical need for FS to combat the curse of dimensionality concerns and find highly useful features in data mining applications such as classification. The use of a new meta-heuristic algorithm incorporated with efficient search strategies in solving HFSPs represents a step forward in using this algorithm to solve other practical real-world problems in a variety of domains. [ABSTRACT FROM AUTHOR]

This paper proposes an optimal control method based on adaptive dynamic programming (ADP) for manipulators with joint limitation under input saturation. The asymmetric input saturation problem is solved by introducing a smooth function, by which the saturation and nonsmooth issues of the input caused by the actuators can be handled. Joint limitation of the manipulator is transformed through a transfer function, which is incorporated into the cost function of the whole robotic system, to guarantee the joint limitation will not be violated. Meanwhile, due to the difficulty in solving Hamilton-Jacobi-Bellman (HJB) equation, the critic network is constructed utilising radial basis function neural networks (RBFNNs) to approximate the cost function. This approach effectively overcomes the curse of dimensionality problem associated with dynamic programming. Subsequently, an ADP-based optimal controller is designed for the robotic system. Lyapunov synthesis is used in the stability analysis to prove all the signals are convergent and ultimately uniformly bounded (UUB). Simulations are conducted on a planar 3-DOF manipulator to validate the effectiveness of the proposed method. The results demonstrate the improved performance and feasibility of the developed ADP-based optimal control strategy in handling joint limitations and input saturation challenges in robotic systems. [ABSTRACT FROM AUTHOR]

We prove an operator-valued Laplace multiplier theorem for causal translation-invariant linear operators which provides a characterization of continuity from H α (R , U) to H β (R , U) (fractional U-valued Sobolev spaces, U a complex Hilbert space) in terms of a certain boundedness property of the transfer function (or symbol), an operator-valued holomorphic function on the right-half of the complex plane. We identify sufficient conditions under which this boundedness property is equivalent to a similar property of the boundary function of the transfer function. Under the assumption that U is separable, the Laplace multiplier theorem is used to derive a Fourier multiplier theorem. We provide an application to mathematical control theory, by developing a novel input-output stability framework for a large class of causal translation-invariant linear operators which refines existing input-output stability theories. Furthermore, we show how our work is linked to the theory of well-posed linear systems and to results on polynomial stability of operator semigroups. Several examples are discussed in some detail. [ABSTRACT FROM AUTHOR]

This paper presents ready-to-use nonlinear and linear averaged models of an improved cascade buck converter (ICBC) for the first time. A detailed steady-state analysis is also given, providing its operating modes, equilibrium values, and design guidelines. The modelling process consists of two stages. First, the nonlinear model is obtained using the state-space averaging technique. Subsequently, the averaged model is linearised by applying the small-ripple approximation and the small-signal model is achieved. Furthermore, the developed small-signal model is employed to derive three significant transfer functions of the converter. The proposed converter model is valid for the continuous conduction mode (CCM) when the duty cycle is lower than $0.5$ 0.5. To be used in validation studies, an exemplary converter with $144{\rm{ W}}$ 144 W rated power that steps down $320{\rm{ V}}$ 320 V input voltage to $24{\rm{ V}}$ 24 V is designed. The accuracy of theoretical analyses is confirmed by the simulation results of the designed converter. Similarly, all proposed models are validated with the simulations done in both frequency-domain and time-domain. The results show that the proposed parametric model response closely matches that of the switching (non-parametric) model and hence it can be safely used for controller design in feedback systems. [ABSTRACT FROM AUTHOR]

Necessity of bandwidth requires the effective use of it for high speed data transmission and faster read/write operation in memory cells. In this paper the transfer function expressions for RC interconnect line is presented for resistive load. The line delay, bandwidth and step response for current and voltage mode signalling is formulated. The current mode and voltage mode signalling provides the 3-dB bandwidth of 6.8 GHz and 3.1 GHz, respectively. An interconnect line modelled as either RLC or RC line depending upon input signal rise time, damping, and range of interconnect length with significant inductance effect is investigated for global interconnect lines. Low swing for column bit line in memory architectures is very important and estimated in terms of dc coefficients. For RC global interconnect of 10 mm, a swing of 0.382 V is obtained for current mode signalling, when a power supply of 1.8 V is applied to the network. DC coefficient and steady state value has been obtained which is significant for power computation on column bit line. It is also analytically validated by SPICE and MATLAB simulations. [ABSTRACT FROM AUTHOR]

The falling weight deflectometer (FWD) test is a prevalent non-destructive testing (NDT) technique in engineering that is essential for evaluating pavement conditions. In this work, the transfer function (TF) theory in frequency domain analysis was applied to address the technical challenges present in FWD research. A pavement system transfer function (PSTF) was proposed as a novel approach for evaluating pavement conditions. The spectral method with fixed-end boundary conditions (B-SEM) was employed to compute the theoretical deflection data for different pavement structures with bedrock during FWD testing. The fast Fourier transform (FFT) technique was used to convert the data into the frequency domain, enabling the construction and calculation of the PSTF. The validity of the PSTF theory was confirmed, and the pavement information contained in the PSTF spectrum was discussed. An analysis and summary are conducted on the impact of variations in pavement attributes on the spectrum. The results indicate that the proposed PSTF contains information regarding pavement system, including the structural layer modulus, structural layer thickness, and bedrock depth. The pavement conditions can be evaluated by directly analyzing the PSTF without considering external factors. The PSTF spectrum is most significantly influenced by bedrock depths between 200 and 500 cm. For every 50 cm variation in bedrock depth, the coefficient of increase and decrease (CIE) of peak frequency ranges from 8.1% to 23.1%. The PSTF spectrum is highly sensitive to variations in the subgrade modulus between 40 and 70 MPa. In this range, the CIE of peak amplitude is greater than 11% for every 10MPa variation in subgrade modulus. The impact of the modulus and thickness of both the surface layer and base layer on the spectrum is noteworthy and should not be disregarded. Spectral analysis is used to summarize the variation in pavement attributes within the PSTF spectrum, serving as a theoretical foundation for further investigations. [ABSTRACT FROM AUTHOR]

Extracellular vesicles (EVs) are abundant in reproductive tract fluids and serve as important mediators of paracrine communication, influencing the function of gametes. Sperm undergo development in the male reproductive tract and exert their function within the female reproductive tract, engaging in interactions with various types of EVs present throughout the reproductive system. Previous studies have demonstrated that both male and female reproductive tract EVs can impact sperm function by transferring regulatory cargoes to them. Nevertheless, inconsistencies of previous research regarding the effects of EVs on sperm function, coupled with a lack of investigation into the influence of female reproductive tract EVs on sperm fertilization, have left the true role and underlying mechanisms of reproductive tract EVs on sperm function largely unexplored. Given that pigs represent significant economic livestock and serve as an ideal biomedical model for human diseases, this review aims to provide a comprehensive summary of the current knowledge regarding reproductive tract EVs and their influence on boar sperm function, while highlighting their potential roles. We anticipate that this review will facilitate future research on reproductive tract EVs and their impact on sperm function, contributing to improved animal reproductive efficiency and advancements in the treatment of male infertility. • EVs are widely existed in the pig reproductive tract. • The reproductive tract EVs in pig could interact with sperm, and influence the sperm fertility. • The miRNAs are important messengers involved in the EVs and sperm interaction. [ABSTRACT FROM AUTHOR]

Fractional calculus is an important mathematical tool that is widely used in control systems. It is established in the literature that fractional order models are more accurate and more effective in system modelling. In this study, an alternative and novel technique is proposed to identify the fractional order time-delayed model of an unknown system. The method is based on obtaining the approximate stability boundary locus (SBL) curve of the unknown system by applying three different experimental tests. Three points on the SBL curve are determined by the experimental tests and then the parameters of the fractional order time-delayed model are computed by solving the nonlinear systems of equation. The system model with double fractional order element plus a time delay is obtained using the proposed method. The proposed method is explained through simulations on a twin rotor system. The proposed method is also used in model order reduction calculation of the higher order transfer functions. [ABSTRACT FROM AUTHOR]

This study aimed to examine different trajectory correction methods for spiral imaging on a preclinical scanner with high‐performance gradients with respect to image quality in a phantom and in vivo. The gold standard method of measuring the trajectories in a separate experiment is compared to an isotropic delay‐correction, a correction using the gradient system transfer function (GSTF), and a combination of the two. Three different spiral trajectories, with 96, 16, and three interleaves, are considered. The best image quality is consistently achieved when determining the trajectory in a separate phantom measurement. However, especially for the spiral with 96 interleaves, the other correction methods lead to almost comparable results. Remaining imperfections in the corrected gradient waveforms and trajectories are attributed to asymmetrically occurring undulations in the actual, generated gradients, suggesting that the underlying assumption of linearity is violated. In conclusion, images of sufficient quality can be acquired on preclinical small‐animal scanners using spiral k‐space trajectories without the need to carry out separate trajectory measurements each time. Depending on the trajectory, a simple isotropic delay‐correction or a GSTF‐based correction can provide images of similar quality. [ABSTRACT FROM AUTHOR]

Traumatic adult brachial plexus injuries typically cause immediate loss of upper limb function. Timely multidisciplinary treatment in specialized centres often results in a useful helper arm. Both the patient and the surgical team can benefit from an open discussion to set realistic expectations. Surgical reconstruction is customized for each patient, considering their injury factors and functional objectives. Optimizing pain control, adherence to procedure indications and using meticulous surgical techniques help minimize the risk of failing to meet the patient's goals. The need for potential alternative treatment(s) if the desired result is not achieved should be detailed before the initial reconstruction. This review discusses late treatment options, including tendon transfers, joint fusions, free functioning muscle transfers and prosthetics, for managing the failed primary reconstruction of the traumatic adult brachial plexus. [ABSTRACT FROM AUTHOR]

Direct current (DC) motors have superior features such as operating at different speeds, being affordable and easily controllable. Therefore, DC motors have many uses, such as machine tools and robotic systems in many factories up to the textile industry. The PID controller is one of the most common methods used to control DC motors. PID is a feedback controller with the terms Proportional, Integral, and Derivative. The proper selection of P, I, and D parameters is critical for achieving the desired control in the PID controller. In this study, the transfer function of a DC motor is first obtained, and the speed of the DC motor is controlled by the PID controller using this transfer function. Then, Particle Swarm Optimization (PSO), an optimization method based on swarm intelligence, is used to adjust the P, I, and D parameters. By using the obtained P, I, and D coefficients, the speed of the DC motor is tried to be controlled, and the effect of the filter coefficient on the system output is examined. The performance of the proposed PSO-PID controller with successful results is given in tables and graphics. Control and optimization studies are carried out with MATLAB Simulink. [ABSTRACT FROM AUTHOR]

Targeting the great demand for adding non‐structural elevators to old residential buildings, this article proposes an updated configuration of tuned mass damper inerter (U‐TMDI) applied in external non‐structural elevators. An analog 2‐DOF system is established to describe the residential building controlled by an inerter elevator. Then, three closed‐form optimal solutions for designing the U‐TMDI are derived via the fixed‐point method, equal modal damping criterion, and the infinity damping assumption. Subsequently, these optimal solutions are compared and discussed involving the expressions of tuning frequency ratio and the optimal damping parameters, root locus diagram and supplemental damping ratios, transfer function, and robustness to frequency variation, respectively. Finally, a residential building example is adopted to validate the feasibility of the proposed retrofitting strategy and the closed‐form optimal design solutions. It is demonstrated that the optimal tuning frequency ratios derived by the fixed‐point method and equal modal damping criterion are different for U‐TMDI due to the influence of elevator stiffness ratio η$\eta $, while its degradation forms for tuned mass damper (TMD) are identical, recognizing the importance of the elevator stiffness. Moreover, the proposed retrofitting strategy of using an inerter elevator can significantly mitigate the main structure displacement by about 18%∼23% for both far‐field and near‐fault earthquakes. [ABSTRACT FROM AUTHOR]

As a distributed ledger technology, blockchain has broad applications in many areas such as finance, agriculture, and contract signing due to its advantages of being tamperproof and difficult to forge. However, the open nature of blockchain also introduces severe privacy issues, currently cryptocurrency privacy protection solutions under account-based models cannot balance the internal verification time and confidentiality of transactions. In order to improve the confidentiality and efficiency of transactions under the account-based model, this paper proposes an access control anonymous payment scheme based on homomorphic commitment and aggregated zero-knowledge proofs, focusing on the realization of a one-to-many anonymous transfer function, one-to-one transfer function, deposit function and withdraw function, to ensure the privacy of a transaction data while reducing verification time and Gas costs. We evaluated our approach on a proof-of-concept implementation by generating Solidity contracts and implemented some interesting contracts. The experimental results show that this scheme not only consumes lower gas, but also reduces the internal time during transaction generation. In addition, our solution has established a one to many transfer transaction scheme, and the proof verification time after aggregation is constant. Thus the efficiency of this scheme is particularly well suited for the digital finance scenarios. [ABSTRACT FROM AUTHOR]

This paper presents theoretical results on entropy-induced thermoacoustics and combustion instability in combustors. The entropy model derived from the thin flame hypothesis, commonly adopted in most network combustor models, inherently assumes that heat and acoustic fluctuations, which serve as sources of entropy waves, are always in-phase. This in-phase property remains unchanged despite the dispersion and dissipation of entropy waves, potentially leading to an underestimation of the entropy wave effect on combustion instability compared to other models that account for flame thickness. This finding suggests that flame thickness should be considered in combustion instability analyses when boundary conditions involve entropy waves, even in one-dimensional cases. Furthermore, this paper demonstrates that the entropy dispersion and dissipation models used in most combustor network models might only partially compensate for the neglected flame width. This perspective, along with a comparative analysis of entropy models that either include or exclude flame thickness, indicates how the free parameters of the dispersion/dissipation models relate to the geometry and operating conditions of a given combustor. Additionally, we present an explicit form of the reflection coefficient for the outlet choking boundary condition under the influence of combustor acoustics. Our theoretical findings are illustrated through numerical examples. [ABSTRACT FROM AUTHOR]

Background Purpose Methods Results Conclusions Image guided radiotherapy (IGRT) with cone‐beam computed tomography (CBCT) is limited by the sub‐optimal soft‐tissue contrast and spatial resolution of energy‐integrating flat panel detectors (FPDs) which produce quasi‐quantitative CT numbers. Spectral CT with high resolution photon‐counting detectors (PCDs) could improve tumor delineation by enhancing the soft‐tissue contrast, spatial resolution, dose‐efficiency, and CT number accuracy.This study presents the first linac‐mounted PCD. On the journey to developing spectral cone‐beam CT for IGRT, the planar image quality of a linac‐mounted PCD is first fundamentally characterized and compared to an FPD in terms of the 2D spatial resolution, noise, and contrast.A Medipix3RX‐based PCD was mounted to the kV FPD of an x‐ray volume imaging (XVI) system on an Elekta linac and the PCD acquisition was synchronized with the pulsed kV source. The energy calibration of the Medipix3RX was determined with various radioisotope gamma emissions up to 60 keV. To compare the 2D spatial resolution and noise between the PCD and FPD, the pre‐sampling modulation transfer function (MTF) and normalized noise power spectrum (NPS) were measured using an RQA5 spectrum and a fluoroscopy phantom was imaged to determine the limiting resolution of line pairs. Spectral planar images of phantom inserts containing two different concentrations of calcium (60 and 240 mg/cc) and iodine (5 and 15 mg/cc) were optimally energy weighted to maximize the contrast using tube voltages of 60, 80, 100, and 120 kV. To account for drifts in the sensor temperature, the PCD was dynamically translated in and out of the insert shadow during acquisitions to obtain flat field corrections per frame. The raw contrast of the resultant planar images was compared to the energy‐integrating FPD.The energy calibration of the Medipix3RX was observed to be linear up to 60 keV. The limiting resolution observed on the fluoroscopy phantom was 2 lp/mm for the FPD and 5 lp/mm for the PCD. The pre‐sampling MTF was higher across all frequencies comparing the PCD to the FPD. The normalized NPS of the PCD did not vary with frequency, whereas the spectrum for the FPD decreased monotonically and was lower than the PCD noise power across most of the spatial frequency range studied due to optical light spreading. Optimal energy weights were applied to the dynamically acquired PCD images and the raw contrast of the 60 mg/cc calcium insert increased by factors of 1.12±0.09$1.12\pm 0.09$ and 1.52±0.22$1.52\pm 0.22$ at 60 and 120 kV respectively compared to the FPD.A Medipix3RX‐based PCD was successfully integrated with the kilovoltage imaging system on an Elekta linac. The initial planar image quality characterization indicated improvements in the MTF and energy‐weighted contrast compared to the FPD. Future work will focus on obtaining linac‐mounted spectral CBCT images with a translate‐rotate geometry, however this initial study indicates that variations in the PCD sensor response during acquisitions must be addressed to realise the full potential of linac‐mounted spectral CBCT. [ABSTRACT FROM AUTHOR]

This paper presents a new structure of a high step‐up DC–DC converter. The proposed converter has one input and two outputs with different voltage levels, suitable for applications that require multiple voltage levels such as photovoltaic systems, electric vehicles and DC microgrids. The proposed converter is expandable to more outputs and has a higher voltage conversion ratio compared to similar converters. The operational modes of the proposed converter are investigated and the conversion ratio of the converter is obtained. Additionally, small‐signal equations of the converter are derived, and using state‐space matrices, transfer functions of the converter are obtained and the controller is designed. Also, the proposed converter is compared with similar converters and power losses equations of the converter are derived. To investigate the converter's performance, simulations are done using MATLAB/Simulink software. Moreover, to validate the theoretical analysis, a laboratory prototype is implemented. The obtained results confirm the operation of the proposed converter. [ABSTRACT FROM AUTHOR]

Due to its unique features, the flyback converter is widely used to convert DC to DC power. This converter has a non‐minimum phase (NMP) dynamic behavior, which is one of its most significant disadvantages. By changing the topology of the flyback converter to a forward‐flyback (FF) converter, the dynamic behavior of the converter can be minimum phase (MP) while the main advantages of the flyback converter such as isolation of the output from the input and simple topology are maintained. This article proposes an innovative FF converter topology by doubling the forward path and adding only one diode and one capacitor. In addition to better dynamic behavior, the proposed double FF (DFF) converter has the same advantages as the conventional FF converter. A new method is used to obtain the transfer function of the output voltage to the duty cycle of the proposed converter. The converter is designed in continuous conduction mode (CCM) with minimum phase dynamics. Finally, simulation and experimental results of both conventional FF and the proposed DFF converters are obtained and compared to validate the superiority of the proposed converter. [ABSTRACT FROM AUTHOR]

The sensitivity of radiochromic films to UV-blue light is increasingly considered for light dosimetry purposes, owing to their bidimensional detection capabilities and ease of use. While film response to radiation intensity has been widely investigated by commercial scanners, spatial resolution studies remain scarce, especially for small field-of-view applications. These are of growing interest due to the antimicrobial or photo-bio-stimulating effects of UV-blue light sources in in vitro, ex vivo and in vivo models, where precise knowledge of irradiation conditions with adequate spatial resolution is crucial. In this study, we report the spatial lateral resolution and contrast reproduction of GAFchromic EBT2 and EBT3 models. Upon film irradiation by a 405 nm laser source or 365 nm LED, a confocal microscope setup was employed to read the film response at 405, 470, 488, 532 and 570 nm wavelengths, with radiant exposure of 10–70 J/cm2. The measured lateral resolution ranged from 8 to 33 μm. The film capability to reproduce contrast across various spatial frequencies (4–14 lines/mm) was evaluated using modulation transfer function analysis with irradiation performed at 365 nm and 405 nm, revealing a pronounced dependency on both radiant exposure and reading wavelength. These results confirm the film capacity to detect and resolve light intensity variability with a ~ 10 μm resolution, with notable applications in micro-beam profiling and light dosimetry. [ABSTRACT FROM AUTHOR]

In this work, we present a comprehensive study of the commutativity of fractional-order linear time-varying systems (LTVSs). Commutativity is a fundamental property in the analysis and control of dynamic systems and is often used to simplify the design of controllers. Fractional-order systems, which are characterized by a noninteger-order derivative, have been widely studied in recent years due to their ability to model a wide range of phenomena. However, the commutativity of fractional-order LTVSs has not been widely explored. In this work, we present a comprehensive study of the commutativity of fractional-order LTVSs. We first provide a mathematical definition of commutativity for these systems and demonstrate that it is equivalent to the commutativity of their transfer functions. We then propose a method for verifying the general condition for commutativity of fractional-order LTVSs under zero initial conditions (ICs) and prove it mathematically. Based on our findings, we realized that the commutative requirements, properties, theories, and conditions are general for fractional-order LTVSs, please observed that some fractional-order LTVSs are commutative, some are not commutative, while some are commutative under certain conditions. Based on this fact, we can say that not all fractional-order LTVSs are commutative.We apply explicit commutative results to several examples of fractional-order LTVSs. Our theoretical and simulation results show a good agreement and prove that our fractional-order LTVSs are commutative under certain conditions, moreover, the commutativity property holds for certain conditions and classes of fractional-order LTVSs, but not for others. Because of the application of fraction commutativity in various fields of science and engineering, we find it necessary to come up with explicit results for the first time. [ABSTRACT FROM AUTHOR]

ABSTRACT This paper discusses an analytical framework to model one‐ and two‐ports in a way which avoids prioritizing either the voltage or the current as model variables. This approach allows for a truly general symbolic treatment of such circuits, avoiding the need to perform repetitive analyses in different working scenarios, and also displays a number of benefits from a theoretical point of view. The key ingredient is a homogeneous version of the Thévenin–Norton theorem for one‐ports which possibly include controlled sources and coupling effects. This paves the way for the introduction of a comprehensive form for the transfer functions and the driving point immittances of two‐ports, accounting for all possible impedance/admittance descriptions of the devices connected at the ports and also of the internal devices. Our framework allows, for example, for a universal definition of reciprocity but also for a straightforward derivation of Middlebrook's formulae in the context of the extra element theorem. Several examples illustrate the results. [ABSTRACT FROM AUTHOR]

We revisit the computation of diurnal and semidiurnal effects of the ocean tide on Polar Motion (PM) and UT1 considering the principal waves of the Ocean Tidal Angular Momentum (OTAM) calculated from the FES 2014 ocean tide atlas. We take into account the recent development of polar motion theory, especially the frequency dependence of the transfer functions in (sub-) diurnal bands. The method of calculating the minor waves is also carefully studied and modified: instead of an interpolation based on neighboring waves, we propose a frequency dependent expression obtained by a linear fit to the admittances and phases of principal waves. Compared in time domain with polar motion (PM) and UT1 derived from Very Long Baseline Interferometry (VLBI) observations, our model performs as well as the recent Desai-Sibois model computed from TPXO8 tidal atlas. The impact of diurnal and semi-diurnal oscillations produced by the luni-solar tidal torque on the asymmetric mean mass distribution of the Earth are observed in the corresponding residuals, which is not the case for the older PM/UT1 model recommended in IERS Convention 2010. More generally, we conclude that tidal modelling of sub-daily terms and corresponding empirical developments are consistent to within 23 μ as for PM and 3 μ s for UT1. In parallel, the effects based on TPXO8 OTAM waves are recalculated according to our method, and present the best agreement with the observations. Our tables, calculated from FES 2014 or TPXO8 OTAM, can be truncated to the 48 or 50 terms with amplitudes above 1 μ as for PM or 0.1 μ s for UT1 to describe those Earth rotation Parameters in a way consistent with their current observation uncertainties. [ABSTRACT FROM AUTHOR]

The wind energy requirements for high temporal and spatial observations, unavailable in many countries, are met by reanalysed wind data, which are increasingly used in wind power assessments. However, these data also include unrealistic features, making their validation compulsory. The validation analysis of ERA5 and MERRA-2 wind data, two of the most successful wind reanalyses, with observations near Morocco's coast, highlighted the existence of bias in both datasets, and other shortcomings. The study was conducted at eight selected sites in the period 2011-2020 using linear and probability density function based statistical tests. The local ERA5-BA and MERRA-2 BA velocity fields were created using Bias Adjustment (BA) Techniques. Only part of the observed and modelled datasets (training period) were used to identify the transfer function. The BA fields were verified against observations during the remaining period (verification period). They outperformed their respective non-adjusted fields and also the WFDE5 (the global bias-corrected ERA5 wind field) in the wind potential assessments, represented by capacity factor and low-wind day. At every location, the relative errors in the latter's estimates using ERA5-BA were lowered to less than 10 %, and the same was true for MERRA-2-BA. Thus, an observational dataset of reduced length can help overcome some reanalysed wind data limitations for wind power estimations. Additionally, this methodology can be applied to the correction of each reanalysis update. [ABSTRACT FROM AUTHOR]

Efforts to optimize the design and enhance the efficiency of standing-wave thermoacoustic refrigerators (SWTARs), particularly those with parallel plate stacks, are crucial for achieving rapid and straightforward engineering estimates. This study primarily focused on optimizing the coefficient of performance (COP) by combining linear thermoacoustic theory (LTT) with the design of experiments (DOE) approach. The investigation centered around five key parameters affecting the COP once the working gas had been selected. Then, based on LTT, the COP was estimated numerically over defined intervals of those five parameters. Moreover, through quantitative and qualitative effect analyses, these five parameters and their interactions were determined. Utilizing a transfer function, the study aimed to delineate the best COP value (1.76) over a defined interval of the parameters as well as the contribution of the thermoacoustic main parameters (55.69%) and their interactions (two-way interactions = 33.30%, three-way interactions = 7.36%, and four-way interactions = 3.35%). Furthermore, a comparison between contour and surface responses and several statistical decision approaches applying the full factorial design verified the robustness of the study's findings. Ultimately, the COP results obtained aligned with the existing literature, underscoring the validity and relevance of the study's methodologies and conclusions. [ABSTRACT FROM AUTHOR]

The precise monitoring of insect pest populations is the foundation of Integrated Pest Management (IPM) for pests of plants, humans, and animals. Digital technologies can be employed to address one of the main challenges, such as reducing the IPM workload and enhancing decision-making accuracy. In this study, digital technologies are used to deploy an automated trap for capturing images of insects and generating centralized repositories on a server. Subsequently, advanced computational models can be applied to analyze the collected data. The study provides a detailed description of the prototype, designed with a particular focus on its remote reconfigurability to optimize repository quality; and the server, accessible via an API interface to enhance system interoperability and scalability. Quality metrics are presented through an experimental study conducted on the constructed demonstrator, emphasizing trap reliability, stability, performance, and energy consumption, along with an objective analysis of image quality using metrics such as RMS contrast, Image Entropy, Image sharpness metric, Natural Image Quality Evaluator (NIQE), and Modulation Transfer Function (MFT). This study contributes to the optimization of the current knowledge regarding automated insect pest monitoring techniques and offers advanced solutions for the current systems. [ABSTRACT FROM AUTHOR]

In this study, the imaging performance of electronic portal imaging devices (EPIDs) is evaluated, comparing measurements collected from EPID images captured at 115 cm, with a field size of 15 × 15 cm2, monitor units (MUs) in the range of 2 MU-100 MU and dose rates (DRs) of 200 MU/min, 400 MU/min and 600 MU/min, using a 6 MV LINAC system and the QC-3V image quality phantom. The analysis includes the normalized contrast transfer function (CTFnorm), the noise power spectrum (NPS) and the information capacity (IC), as well as the signal-to-noise frequency response (SNFR), which can be used as a comprehensive quality index. The results of our study are compared with previously published data captured at 100 cm under similar exposure conditions. They show similar CTF curves with different source-to-phantom distances, with the lowest values observed at specific MU and DR combinations. Moreover, NPS graphs are found to decrease with respect to spatial frequency. SNFR values also display a reduction with increasing spatial frequency. In addition, irradiation with the phantom placed closer to the EPID, 115 cm from the LINAC, yields better SNFR and IC performance characteristics, indicating better delineation of the organs closer to the EPID. The testing of EPID performance may potentially benefit from our results, which may lead to improvements in the quality of radiotherapy treatments. [ABSTRACT FROM AUTHOR]

This study presents the design, fabrication, and characterization of a wide field-of-view (FOV) metalens optimized for capsule endoscopy. The metalens achieved a 165° FOV with a high modulation transfer function (MTF) of 300 lines per millimeter (lp/mm) across the entire FOV, operating in the near-infrared (NIR) narrow-bandpass imaging at 940 nm. The performance of the metalens-based system is evaluated using two bandwidths, 12 nm and 32 nm, showing MTF values of 0.2 and 0.3 at 250 lp/mm, respectively. The metalens-based system maintains a compact form factor with a total track length of 1.4 mm and a diameter of 1.58 mm. Compared to a traditional 108° FOV endoscope, the nano-optic capsule endoscope demonstrated superior performance in terms of FOV, contrast, and resolution. This advancement represents a significant step toward enhancing diagnostic capabilities in medical imaging, offering improved performance in a more compact package compared to conventional optics. [ABSTRACT FROM AUTHOR]

This study compares the optical quality of zonal refractive multifocal and diffractive bifocal intraocular lenses (IOLs) and visual outcomes after implantation in 93 patients(93 eyes) with cataracts and high myopia. A retrospective analysis was conducted to measure visual acuity at far, intermediate, and near distances, defocus curves, wavefront aberrations, modulation transfer function (MTF), a Quality of Vision questionnaire (QoV) and visual quality self-evaluation were examined at 3 months. The results demonstrated the ZMB group showed better uncorrected near visual acuity (P < 0.01), and the MF15 group showed better uncorrected intermediate visual acuity (P < 0.001). The ZMB group provided better MTF than the MF15 group (P < 0.01) but demonstrated a worse QoV score, especially for the severity of glare, halo, and starburst (P < 0.05). The satisfaction score and spectacle independence rate in the ZMB group were higher than in the MF15 group (P < 0.01). LS-313MF15 and TecnisZMB00 offered excellent visual restoration, stable distance visual acuity, and good subjective visual function. [ABSTRACT FROM AUTHOR]

The MAJIS (Moons and Jupiter Imaging Spectrometer) instrument is an imaging spectrometer on-board the JUICE (JUpiter ICy moons Explorer) spacecraft. MAJIS covers the spectral range from 0.5 to 5.54 μm with two channels [visible–near infrared (VISNIR) and IR]. A comprehensive campaign of on-ground MAJIS calibration was conducted in August and September 2021 in the IAS (Institut d'Astrophysique Spatiale, CNRS/Université Paris-Saclay) facilities. In this article, we present the results relevant for the radiometric calibration of MAJIS. Due to the specific characteristics of the MAJIS detectors (H1RG from Teledyne), an extensive detector characterization campaign was implemented for both the VISNIR and IR detectors before integration so as to validate readout procedures providing precision and accuracy. The characterization also provided critical information on linearity and operability as a function of the integration time and operating temperature. The radiometric calibration of the integrated MAJIS instrument focused on the determination of the instrument transfer function in terms of DN output per unit of radiance for each MAJIS data element as a function of its position in the field of view of MAJIS and its central wavelength. The radiometric calibration of the VISNIR channel required a specific procedure due to stray light at short wavelengths. Observations of an internal calibration source during calibration and after launch (April 14, 2023) showed that there were minor changes in both the VISNIR and IR channels. The instrument transfer functions to be used in flight have been updated on this basis. [ABSTRACT FROM AUTHOR]

Given the presence of various non‐ideal conditions, such as detection errors, converter non‐linearity, noise, and parameter mismatches, the flux model experiences the introduction of DC bias and high‐frequency harmonics, which subsequently deteriorate the accuracy of flux estimation. To dispose these issues, an improved non‐linear flux observer (FOIFFO) using a second‐order generalised integrator as an in‐loop filter is proposed for the sensorless control of permanent magnet synchronous motors. The observer demonstrates robust performance in eliminating DC bias and having a strong filtering ability for high‐order harmonics even without amplitude and phase compensation to accurately estimate the rotational speed and rotor position. The performance of the method is analysed by transfer functions and bode plots, while the discretisation method of the FOIFFO is proposed. Finally, the new sensorless control strategy is verified by synthesising the experimental results. [ABSTRACT FROM AUTHOR]

Distributed Acoustic Sensing (DAS) is a photonics technology converting seafloor telecommunications and optical fiber cables into dense arrays of strain sensors, allowing to monitor various oceanic physical processes. Yet, several applications are hindered by the limited knowledge of the transfer function between geophysical variables and DAS measurements. This study investigates the quantitative relationship between surface gravity DAS‐recorded wave‐generated strain signals along the seafloor and the pressure at a colocated sensor. A remarkable linear correlation is found over various sea conditions allowing us to reliably determine significant wave heights from DAS data. Utilizing linear wave potential theory, we derive an analytical transfer function linking cable deformation and wave kinematic parameters. This transfer function provides a first quantification of the effects related to surface gravity waves and fiber responses. Our results validate DAS's potential for real‐time reconstruction of the surface gravity wave spectrum over extended coastal areas. It also enables the estimation of waves hydraulic parameters at depth without the need from offshore deployments. Plain Language Summary: Distributed Acoustic Sensing (DAS) technology converts submarine communication cables into real‐time networks of thousands of seismo‐acoustic sensors. The high sensitivity of DAS measurements (nano‐deformation) makes the recorded signals extremely rich in information, and capable of capturing multiple oceanographic processes. Numerous applications can be envisaged such as monitoring turbidity currents, tsunamis, marine renewable energy parks, etc., and some are already in progress, including monitoring surface vessels, marine currents, cetaceans, etc. However, despite all these developments, the relationship between DAS measurements and certain key ocean variables remains poorly understood. In the littoral zone, this study aims to investigate the link between the deformation signals recorded by DAS due to wave passage at the sea surface and the pressure measured by a sensor located nearby, at the bottom. Our findings demonstrate a strong correlation under varying sea conditions. This correlation allows to reliably determine significant wave heights using DAS data. By applying a simplified theory of wave propagation, the linear wave theory, it was possible to develop an analytical transfer function that relates cable deformation to wave movement parameters. The results confirm that DAS has the potential to reconstruct parameters associated with ocean waves, and could ultimately facilitate their real‐time estimation. Key Points: A simple transfer function between Distributed Acoustic Sensing (DAS) and a collocated pressure sensor is retrieved for surface gravity waves heightsOcean waveheights are correctly reconstructed from nearshore DAS measurementsThe signals recorded by DAS can be described from the standpoint of the linear wave theory [ABSTRACT FROM AUTHOR]

This paper presents a novel low-power low-voltage current differencing transconductance amplifier (CDTA). To achieve a low-voltage low-power CDTA, the BD-MOST (bulk-driven MOS transistor) technique operating in a subthreshold region is used. The proposed CDTA is designed in 0.18 µm CMOS technology, can operate with a supply voltage of 0.5 V, and consumes 1.05 μW of power. The proposed CDTA is used to realize a current-mode universal filter. The filter can realize five standard transfer functions of low-pass, band-pass, high-pass and band-stop, and all-pass from the same circuit. Neither component-matching conditions nor input signals of the inverse type are required to realize these filter functions. The current-mode filter offers low-input and high-output impedance and uses grounded capacitors. The natural frequency and quality factor of the filters can be orthogonally controlled. The proposed CDTA and its applications are simulated using SPICE to confirm the feasibility and functionality of the new circuits. [ABSTRACT FROM AUTHOR]

The modular multilevel converter (MMC) plays an important role in large-scale renewable energy integration and transmission, and it can also operate in standalone mode, powering AC passive loads. This paper focuses on the impact of load variation on the stability of the MMC. First, the impact of load variation on the MMC transfer function is analyzed in detail using the harmonic state-space (HSS) modeling method. Then, by means of the impedance-based stability analysis method, it is found that the MMC tends to become unstable with the increase in inductive loads. If the controller is not well-designed, the system may fail when loads change. Therefore, the worst-case design is used to guarantee the overall system's stability under all load conditions. The impact of traditional proportional resonant (PR) controller parameters on the system's stability is analyzed, revealing that the stability margin and control performance of the controller are limited. Thus, an improved controller structure with an additional series of compensators is proposed. Extensive simulation results in MATLAB/Simulink R2024a verify the analysis of this work and the effectiveness of the proposed controller. [ABSTRACT FROM AUTHOR]

To address the issues of image blurring and color distortion in hazy conditions, an image restoration method based on a parametric analytical modulation transfer function model is proposed under turbid atmospheric conditions. A source database is established using a numerical radiative transfer method based on discrete ordinate. Through multivariate nonlinear fitting and linear interpolation, the quantitative relationships among critical spatial frequency, turbid atmospheric MTF, and key atmospheric optical parameters—such as optical thickness, single scattering albedo, and asymmetry factor—are examined. A fast and efficient parametric analytical MTF model for turbid atmospheres is developed and applied to restore images affected by fog. The results demonstrate that, within the applicable range of the model, the model's maximum mean relative error and the root mean square error are 7.16% and 0.0454, respectively. The computational speed is nearly a thousand times faster than that of the numerical radiative transfer method, achieving high accuracy and ease of application. Images restored using this model exhibit enhanced clarity and quality, effectively compensating for the degradation in image quality caused by turbid atmospheres. This approach represents a novel solution to the challenges of image processing in complex atmospheric environments. [ABSTRACT FROM AUTHOR]

This paper investigates the control performance of a novel grounded inerter-based dynamic vibration absorber (GI-DVA) for random vibration reduction. First, the dynamics equations of the coupled system are written and the transfer function is obtained based on the Laplace transform. Then, assuming that the primary structure is under random white noise excitation, the displacement variance of the primary structure is calculated based on the exact definition of the H 2 norm, by solving the Lyapunov equation. By imposing that the partial derivatives of the response variance of the primary structure with respect to the system parameters are simultaneously equal to zero, the optimum design values of the H 2 optimized GI-DVA were derived numerically for given different mass ratio. It can be found that the optimal design parameters as the inerter-to-mass ratio, the stiffness ratio and the damping ratio increase, while the frequency ratio decreases with the increase in the mass ratio. Under the optimal conditions, the response analysis showed that the primary structure response controlled by the H 2 optimized GI-DVA can decrease with the increase in the mass ratio, but is less sensitive to large mass ratios, and can be robust to the mistuning on the optimum design parameters. Then, the control performance evaluation is first performed in the frequency domain, which reveal that the dynamic response reduction capacity of the H 2 optimized GI-DVA are significantly 62% and 48% superior to the H 2 optimized classic DVA (CDVA) and high-performance passive nontraditional inerter-based DVA (NIDVA-C4), respectively. Furthermore, for the root mean square response evaluation (H 2 performance), the H 2 optimized GI-DVA can provide significantly H 2 performance 58% and 50% than the H 2 optimized CDVA and NIDVA-C4, respectively. To obtain more realistic results, the time domain simulation is performed, which showed that the GI-DVA can provide significantly performance for random vibration reduction. [ABSTRACT FROM AUTHOR]

An environmental proxy routinely used in paleoecological studies of peatlands is testate amoebae, which are used to infer successional and hydrological shifts through time. However, since many species of protists globally remain undescribed, important ecological information about community assemblages and their interaction with environmental conditions in both the past and present has potential gaps. During the analysis of testate amoeba assemblages from peat cores across the Hudson and James Bay region of Canada, a testate amoeba that has not been formally described was discovered with high abundance in subfossil assemblages (up to 50%). We describe this new species, Pyxidicula muskegii sp. nov., using morphometric measurements of tests from these peat core records and demonstrate its environmental preferences using modern samples collected from the same region. The hemispheric shape and irregular areolar surface pattern on the test, along with its preference for lawns in both fens and bogs, support that P. muskegii is a new species. This species is also found in much lower relative abundance in modern samples (<3%) than in paleo-peat core records. This difference in modern and paleo-assemblage suggests that there is a taphonomic bias in their relative abundance with depth, which we attribute to their organic test that is less prone to decomposition. Therefore, it is critical to include rare taxa within future transfer function models to incorporate their environmental tolerances and improve model predictions. [ABSTRACT FROM AUTHOR]

Kramers–Kronig relations link the real and imaginary parts of the Fourier transform of a well-behaved causal transfer function describing a linear, time-invariant system. From the physical point of view, according to the Kramers–Kronig relations, absorption and dispersion become two sides of the same coin. Due to the simplicity of the assumptions underlying them, the relations are a cornerstone of physics. The rigorous mathematical proof was carried out by Titchmarsh in 1937 and just requires the transfer function to be square-integrable (L2), or equivalently that the impulse response of the system at hand has a finite energy. Titchmarsh's proof is definitely not easy, thus leading to crucial steps that are often overlooked by instructors and, occasionally, prompting some authors to attempt shaky shortcuts. Here, we share a rigorous mathematical proof that relies on the Laplace formalism and requires a slightly stronger assumption on the transfer function, namely it being Lebesgue-integrable (L1). While the result is not as general as Titchmarsh's proof, its enhanced simplicity makes a deeper knowledge of the mathematical aspects of the Kramers–Kronig relations more accessible to the audience of physicists. Editor's Note The Kramers–Kronig relations are fundamental to optics, linking dispersion to absorption. While incomplete proofs are found in many textbooks, the rigorous mathematical proof that requires the minimal assumption (that the transfer function is square-integrable) is quite challenging and, therefore, rarely taught. In this paper, the authors show that requiring a slightly stricter criterion for the transfer function (L1 = Lebesgue-integrable) allows the proof to be much more accessible. [ABSTRACT FROM AUTHOR]

Since decades mathematicians have been designing the transfer function for the available physical models followed by the involvement of control engineers to work on it. Through the study of the offered representations, many systems were found to be of higher order which are nevertheless not easy to study and analyze in their core form. Furthermore, again uncertainties within the system was found that cannot be ignored. All these increases the complexities for analysis of the physical systems. This demands a technique for order reduction to derive an approximate lower order representation of the higher order systems. In continuation, this paper is an attempt to propose a computationally efficient approach for obtaining the reduced interval model based on Routh Approximation technique. The proposed approach is a novel method for discrete-time interval system and is discussed in detail in the article content ahead. The provided examples offer the desired explanation for the effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

This paper presents a methodology for finding a pseudo-upper or lower triangular state-space realization (SSR) from an incommensurate fractional-order transfer function. This SSR is obtained for a particular case of incommensurate fractional-order systems that can be represented by pseudo-upper or lower triangular multi-order state-space equations, which are derived by drawing the block diagram of the transfer functions. The obtained realization is very similar to the controllability canonical form for ordinary transfer functions. It is demonstrated that the obtained realization is controllable. Thus, the state feedback controllers can be systematically designed for these systems. [ABSTRACT FROM AUTHOR]

Frequency-domain modeling is a core tool for the analysis of linear time-invariant structures. In a process that has been unclear, additional Dirac delta distributions can arise in the frequency-domain transfer functions of certain structures, beyond those seemingly given by the structural model—e.g., in the mechanical impedance of a linear spring. Previous analyses have manually appended these "hidden deltas" to the relevant transfer functions in to ensure that they remain causal, but questions remain as to their exact origin and behavior in in noncausal models. Here, we demonstrate that these hidden deltas arise from the theory of distributions and the solution of the distributional division equation. We demonstrate a rigorous and reliable method for deriving these hidden deltas in which the role of causality constraints are made clear. Furthermore, we demonstrate that the appropriate frequency-domain conditions for causality in such systems are generalized—not classical—Hilbert transform relations, and that the process of appending delta distributions is related to the analysis of causality via these generalized relations. [ABSTRACT FROM AUTHOR]

Defining the required trackability level of the target condition for the testing facility reconditioning unit represents an unresolved challenge in improving the reproducibility of load-based tests and corresponding performance rating standards development. To enhance the reproducibility of such testing methodology, this paper presents and discusses a new feed-forward compensation technique based on the development of a transfer function model for the delay and offset characteristics of the psychrometric room's air temperature and humidity modulations with reference to the target signal from the room emulator. It is demonstrated that the proposed methodology enables offset and delay reduction in the trackability of the return air condition within 60 s at different testing conditions, enhances the reproducibility of the test results to limit performance deviations to within 2 %, and achieves closely matched controlled parameter modulations during load-based tests. [ABSTRACT FROM AUTHOR]

Objective: The goal of this study was to examine the relationship between lap belt tension and force measured at the iliac wing and the effects of model type and torso posture on this relationship. From this analysis, preliminary transfer functions were developed to predict loads applied to the iliac wing as a function of lap belt tension at magnitudes typically measured in sled and vehicle crash tests. Methods: A DOE study was conducted to provide a robust assessment of the lap belt-pelvis load relationship under various conditions. The GHBMC, THUMS, and THOR FE models were positioned in upright and reclined postures with several other intrinsic and extrinsic parameters varied for a total of 360 simulations. For the HBMs, instrumentation was developed to measure ASIS load at each iliac wing. Simulations that resulted in submarining were identified and removed from the subsequent development of lap belt-ASIS force transfer functions. Results: The GHBMC exhibited submarining more frequently than the THUMS and THOR models. In addition to submarining, there were several cases in which the lap belt remained below the ASIS instrumentation or roped during the model's forward excursion. These phenomena, particularly prevalent in the THUMS model, also influenced how the lap belt engaged the ASIS instrumentation and were thus eliminated from the transfer function development. Transfer functions relating peak lap belt tension and corresponding ASIS force magnitudes were developed for the GHBMC and THOR models in upright and reclined postures. In the upright posture, the THOR showed a higher level of ASIS load measured for a given level of lap belt tension than the GHBMC; however, in recline the lap belt-pelvis load relationship was similar between the two models. Conclusions: The lap belt-pelvis load relationship was found to be affected by model type, posture, the area in which the ASIS instrumentation was defined, and occupant kinematics. This study showed it was possible to minimize the ASIS force by having the lap belt engage low on the pelvis and upper thighs, though further study is needed to determine if this loading mechanism is truly protective from an injury standpoint or an artifact of bypassing the ASIS instrumentation. The transfer function that showed the highest ASIS force measured for a given level of lap belt tension is recommended for future use. [ABSTRACT FROM AUTHOR]

Monitoring domestic activities helps us to understand user behaviors in indoor environments, which has garnered interest as it aids in understanding human activities in context-aware computing. In the field of acoustics, this goal has been achieved through studies employing machine learning techniques, which are widely used for classification tasks involving sound recognition and other objectives. Machine learning typically achieves better performance with large amounts of high-quality training data. Given the high cost of data collection, development datasets often suffer from imbalanced data or lack high-quality samples, leading to performance degradations in machine learning models. The present study aims to address this data issue through data augmentation techniques. Specifically, since the proposed method targets indoor activities in domestic activity detection, room transfer functions were used for data augmentation. The results show that the proposed method achieves a 0.59% improvement in the F1-Score (micro) from that of the baseline system for the development dataset. Additionally, test data including microphones that were not used during training achieved an F1-Score improvement of 0.78% over that of the baseline system. This demonstrates the enhanced model generalization performance of the proposed method on samples having different room transfer functions to those of the trained dataset. [ABSTRACT FROM AUTHOR]

Coatis optimization algorithm (COA) has recently emerged as an innovative meta-heuristic algorithm (MA) for global optimization, garnering considerable attention from scholars and researchers. In this paper, we introduce three techniques to enhance COA: (1) the cooperative mechanism, (2) the fitness-based division, and (3) the optional base vector strategy. Collectively, we refer to our improved method as cooperative COA (CCOA). In addition, we introduce the incorporation of the S-shaped Sigmoid transfer function and the V-shaped Tanh transfer function into CCOA, leading to the development of SCCOA and VCCOA. These adaptations effectively address the challenges posed by feature selection tasks and the 0/1 knapsack problem. To comprehensively evaluate the performance of the continuous version of CCOA, as well as the binary versions of SCCOA and VCCOA, we conducted two distinct categories of numerical experiments. Firstly, we compared CCOA with nine representative MAs, including the original COA, on CEC2020 benchmark functions and six engineering optimization problems. Secondly, SCCOA and VCCOA are compared with six famous binary MAs on 13 feature selection datasets and 18 standard 0/1 knapsack problems. Experimental and statistical results show the competitiveness of CCOA and its binary versions, and it is promising to extend CCOA to various real-world application scenarios. [ABSTRACT FROM AUTHOR]

With the development of high-speed analog-to-digital converter (ADC)-based wireline receivers, the Mueller–Muller clock and data recovery (MM-CDR) circuit has garnered increasing attention. But in the design stage, evaluating the loop performance of MM-CDR circuits in ADC-based wireline receivers is challenging due to the absence of a linearized model for a Mueller–Muller phase detector (MMPD). In this paper, a linearized model of the MMPD is proposed by analyzing the output probability of the MMPD in different transition patterns with random jitter injection, and the model is combined with an entire MM-CDR system to analyze the performance of the MM-CDR loop. Analysis of the linearized model and corresponding simulations indicate that when the reference voltage level in the MMPD is set equal to the amplitude of the average crossing voltage at the intersection of 011 and 110 patterns, the MMPD can obtain the maximum gain, which is determined by jitter, and the jitter transfer function and jitter tolerance can achieve optimum performance. [ABSTRACT FROM AUTHOR]

To achieve the broadband applicability of standard voltage transformers in "dual high" power systems, an equivalent circuit model of the standard voltage transformer is first established. Using the complex magnetic permeability method and utilizing existing core parameters, the excitation impedance values are obtained. Next, based on the equivalent circuit model, the no-load error function of the standard voltage transformer is analyzed, and through simulation, the no-load error response curve of the standard voltage transformer in the frequency range of 20 Hz to 3000 Hz is derived. The simulation results indicate that within the 20 Hz to 700 Hz range, both the no-load ratio error and the no-load angular error meet the accuracy requirements, with the ratio error within ±0.05% and the angular error within 2′. Additionally, the derivation of the error transfer function demonstrates the correlation between the no-load error values and the number of turns and cross-sectional area of the standard voltage transformer. Simulation results, obtained by increasing and decreasing the number of turns and cross-sectional area by 10%, provide valuable insights for the error compensation and structural design of standard voltage transformers. [ABSTRACT FROM AUTHOR]

There has been a significant rise in the ways the internet caters to day-to-day usage in everyday lives. Significant presence in connecting IoTs, helping via online education, entertaining through online games, taking business decisions, and many more. Therefore, all these activities generate an abundance of data and require its management as well. There is a need to secure these networks from malicious attackers to prevent any harmful acts. Network security is still an attractive topic to conduct research on. In this paper, the Net Flow-based dataset NF-UNSWNB15-v2 has been considered for the experimentation and tried to resolve problems in building IDS. Problems like handling a large number of features have been addressed by utilizing FOX optimization with a V-shaped transfer function for binarization purposes and selecting the optimal features. Further classifying it using Light-GBM and evaluating the results for the binary and multi-class classifications. The proposed model selects minimum number of features for both binary and multi-class classification as compared to the other existing methods. Further evaluating on various parameters, the proposed approach performs satisfactorily and improvement in detection rate for various attacks like DoS, Exploits, Fuzzers etc. has been observed. [ABSTRACT FROM AUTHOR]