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Polarization diverse design of the transmit waveforms based on the property of the target scattering matrix provides better performance than transmitting waveforms with fixed polarizations, especially for mainlobe interference suppression applications. In this work, we propose a radar system combines the advantages of multiple-input–multiple-output (MIMO) systems with the advantages offered by optimally choosing the transmitter polarizations, in order to achieve a better mainlobe interference suppression performance. The polarization diversity is employed in the transmit array, while the receive array adopts 2-D vector sensors to measure the horizontal and vertical components of the received signal. The optimal transmitter polarizations can be obtained by maximizing the output signal-to-interference-plus-noise ratio (SINR) in each coherent processing interval (CPI). In addition, the discrimination method for the target and the interference is studied in this paper, along with the target scattering matrix estimation method. Simulation results demonstrate that interference can be effectively discriminated and suppressed with the radar configuration, and better interference suppression performance is achieved with the optimal transmitter polarizations. [ABSTRACT FROM AUTHOR]

Purpose This paper aims to describe a simple low-pass filter to suppress torque pulsation and current harmonics in permanent magnet synchronous motor (PMSM) drives.Design/methodology/approach For the control of the PMSM, a field-oriented control algorithm is always used. The proposed filter is actually a resistance, inductance, capacitance (RLC) filter. At the output of the inverter and the input of PMSM, an RLC filter is connected. This filter suppresses current harmonics through filtering phase voltage harmonics. Analysis of the filter is achieved through frequency characteristics analysis.Findings This filter can effectively filter out the harmonic of phase voltage. Both the simulation and experiment results show that the proposed filter can effectively suppress torque pulsation and current harmonics in PMSM drives. Also, the method of selecting filter parameters and the whole control system are very simple.Research limitations implications The filter increases the design cost of the system.Practical implications The harmonics and torque ripple of phase current are greatly suppressed. Also, the loss of the PMSM reduced.Originality/value The method of selecting filter parameters and the analysis of the proposed filter are proposed for the first time. [ABSTRACT FROM AUTHOR]

A trove of internal ByteDance documents reveals how TikTok's parent company tracks "sensitive words" mentioned on its social media apps, with the potential to shape high stakes discourse on global politics, culture and society. [ABSTRACT FROM AUTHOR]

In this work, we investigate the synchronization of neuronal activity through a model of a clustered network formed by scale-free subnetworks. These simulate the areas of the cerebral cortex and capture the spatial distribution of the vertices. The growth of the scale-free subnetworks takes place according to the fitness model, and the architecture of the clustered network presents internal and external links to simulate connections inside and between cortical areas. The corticocortical connections are established according to a human connectivity matrix obtained through experimental data. The model also considers electrical and chemical synapses. A two-dimensional map, in the bursting regime, simulates the dynamic behavior of the neuron. The high synchronization of neuronal activity is revealed by the Kuramoto order parameter. To corroborate the analyses using the order parameter, we calculate a suppression measure. In order to suppress this synchronization, we propose a three-stage switching control as a function of the delayed mean-field in each subnetwork. This suppressor agent is effective in two scenarios, whether applied according to the spatial distribution of neurons or in the emitting hubs of the subnetworks. Our results show that the fitness model has a relevant role in the study of neuronal activity suppression, allied to the application of a three-stage switching control by means of a time-delayed feedback method being an efficient way to suppress synchronization in clustered networks. • We simulate cortical areas according to the fitness model to investigate the influence of hubs in the suppression of network synchronization. • The cortical areas are interconnected forming a clustered network to show emerging synchronization effects in the cerebral cortex. • We apply a synchronization suppressor agent acting like a three-stage switching to the network. • Our results have shown that the graph topology used to simulate the cortical areas play an important role in suppressing synchronization. [ABSTRACT FROM AUTHOR]

This article presents a study based on a survey of twenty forest fire experts in Spain, the objective of which is to identify the main problems and possible measures that could be taken with regard to road design in order to contribute to the prevention and suppression of forest fires. The questions dealt with themes such as the maneuverability of specialized extinguishing equipment, the maintenance of areas adjacent to roadways, preventative forestry measures, fire-resistant vegetative species that could be planted adjacent to roads, smoke detectors and environmental education. They were also asked if roads themselves could act as firebreaks, as anchor points for a backfire, or as heliports, and about the relationship between roadways and water points in forested areas for supplying and managing water reserves. This article, by means of a survey o f experts, has served to detect critical elements of forest fires in which roads play an important role. It also paves the way for future research into the design and exploitation of roadways in forested areas to prevent fires and facilitate their suppression. [ABSTRACT FROM AUTHOR]

Abstract: In order to investigate the effects of an elastically-linked moving body on liquid sloshing inside a tank, an analytical formulation and a numerical approach were proposed to assess hydrodynamic loads in a partially filled rectangular tank with a body connected to the tank by springs. The analytical approach was developed based on the potential theory to calculate fluid velocity field, and the dynamics of the liquid sloshing coupled to the moving body are described as a mechanical system with two degrees of freedom. The coupling between the fluid and the moving body is given by a damping force calculated based on the body geometry and the fluid velocity field. The proposed numerical approach is based on the Moving Particle Semi-implicit (MPS) method, which is a Lagrangian particle-based method and very effective to model nonlinear hydrodynamics due to fluid–structure interaction. In the numerical approach, the rigid body is modeled as a cluster of particles and the motions are calculated considering its mass, moment of inertia, hydrodynamic loads and springs restoring forces. The elastic link between the body and tank is modeled by applying Hooke’s law. Simple cases of floating body motion were used to validate the numerical method. Finally, analytical and numerical results were compared. Despite its simplicity, the analytical approach proposed in the present work is an efficient approach to provide qualitative understanding and a first estimate of the moving body effects on the sloshing inside the tank. On the other hand, the numerical approach can provide more detailed information about the coupling phenomena, and it is an effective mean for the assessment of the reduction of the sloshing loads due to the moving body with elastic link. Finally, the effectiveness of the concept as a sloshing suppressing device is also investigated. [Copyright &y& Elsevier]

The article focuses on the legal problem arising from incorrect information posted by users in Wikipedia. This problem was highlighted by a post of an anonymous user of a biography of former U.S. Attorney General Robert Kennedy which linked him to the assassinations of the late President John F. Kennedy and his brother Robert Kennedy. The free online encyclopedia is written and edited by various anonymous volunteers who are free to submit new articles that could reach a very large audience.

In order to obtain a correct interpretation of a vertical electrical sounding (VeS), the suppression and equivalence principles must be considered, for generating multiple models as a consequence of the non unicity of the solution of the inverse problem. Among all the valid solutions, one must be found that agrees the most with the VeS nearby, that has a good geological meaning in function of the previous information of the site and that agrees with the hypothesis formulated during the research, just as it was done in the location of Santa Lucía Cotzumalguapa, Guatemala. [ABSTRACT FROM AUTHOR]

• We proposed a mathematical model based on Rulkov map to built a network of networks model for coupled bursting neurons. • We use scale-free networks for the cortical areas and a human connectivity matrix for the connections among the cortical areas. • It is possible to suppress bursting synchronization in the network by applying an external time-delayed feedback signal. We investigate the synchronization properties of a neuronal network model inspired on the connection architecture of the human cerebral cortex. The neuronal model is composed of an assembly of networks, where each one of them is a scale-free network and the connections between them are taken from a human connectivity matrix proposed by Lo and collaborators [J. Neuroscience 30 , 16876 (2010)]. The neuronal dynamics is governed by the Rulkov two-dimensional discrete-time map and the coupling between neurons and the different cortical regions occurs by means of chemical synapses. Individual neurons display bursting activity with characteristic phases and frequencies. Bursting synchronization is achieved for certain values of the chemical coupling strength in the network model and can be related to the presence of some pathological rhythms. The total or partial suppression of bursting synchronization has been pointed as a dynamical mechanism underlying deep brain stimulation techniques to mitigate such pathologies. In this work a synchronization suppression technique is employed through the application of an external signal based on the time-delayed mean field in certain areas of the neuronal network. Our results show that the suppression of synchronization depends on the values of the time delay and intensity of the applied signal. [ABSTRACT FROM AUTHOR]

The Great Leveler; Increased Cancer Risk in HIV (Even With Long-Term Suppression) [ABSTRACT FROM AUTHOR]

A circuit is described that is capable of blanking leading zeros in multiplexed displays that use the 74C925 Series counter-driver. With the use of an additional flip-flop and a few modifications, the scheme is extended to cascaded counters with multiplexed 7-segments. A schematic diagram is included.