This brief proposes two leader-follower affine formation control algorithms for a class of second-order uncertain multi-agent systems. The model each agent is described by the dynamics with nonlinear uncertainties. Due to high robustness, flexibility and maneuverability, approaches based on stress matrix are adopted achieve target formation, in which laws designed followers keep desired configuration respect leaders. First, considering that velocities leaders constant, we design an estimator...

In this paper, the problem of interest is efficient estimation log-normal means. Several existing estimators are reviewed first, including sample mean, maximum likelihood estimator, uniformly minimum variance unbiased estimator and a conditional minimal mean squared error estimator. A new then proposed, we show that it improves over in terms risk. The improvement more significant with small sizes large coefficient variations, which common clinical pharmacokinetic (PK) studies. addition, very...

Ultrathin foils are used in multiple fields, including aerospace, and precision instrument design. In this paper, CoCrNi medium-entropy alloy (MEA) ultrathin with terminal thicknesses of 77 μm were prepared by accumulative cold rolling at room temperature. The quasi-static tensile properties the rolled tested. influence reduction ratio thickness values on their mechanical was studied through EBSD TEM. results showed that MEA exhibited excellent performance when reached 160 μm, which strength...

Abstract This article studies optimal leader‐follower affine formation control for linear multi‐agent systems, which has more flexibility due to the usage of stress matrices. First, based on inverse optimality strategy, an law is designed drive followers their target positions, in a corresponding performance index minimized. Next, minimize prespecified index, another class proposed by using cooperative estimator. The design estimator proportional‐integral feedback estimates position each...

The automatic monitoring/tracking of environmental boundaries by multi-agent systems is a fundamental problem that has many practical applications. In this paper, we address with formation control techniques based on parame tric curves represent the boundary’s feedback shape. For that, approximate curve truncated Fourier series, whose finite coefficients are utilized to characterize curve’s shape and automatically distribute agents along it. These exploited design new type controller drives...

According to the cone-type throttle valve is prone cavitation, resulting in reduction performance of cone valve. Here, a visual experimental platform for hydraulic cavitation built, and number conical under different working pressure, opening degree, back pressure studied. The image conditions obtained. research shows that properly increasing reducing system keeping small port can restrain cavitation.

Compared to the conventional Earth observation satellites, agile satellites have stronger attitude adjustment capability along three axes which also make scheduling problem more difficult. This paper proposes a new variable duration method based on quantum genetic algorithm for at multiple tasks. First, we model and take profits as performance function that combines task priority duration. Then, propose coding includes actual start time Based good continuous space search ability of...

<p>The automatic monitoring/tracking of environmental boundaries by multi-agent systems is a fundamental problem which has many practical applications. In this paper, we address with formation control techniques based on parametric curves that represent the boundary’s feedback shape. For that, approximate curve truncated Fourier series, whose finite coefficients are utilized to characterize curve’s shape and automatically distribute agents along it. These exploited design new type...

A broadband circularly polarized (CP) antenna for millimeter wave (mmWave) communications is proposed. The fed by a microstrip line and the energy coupled through slot in middle layer to excite driven patch radiation on top layer. rotated with an angle generate CP waves. Based element, 4×4 array full-corporate feeding network designed, fabricated measured. measured results show that -10 dB impedance bandwidth covered from 22 30 GHz, relative exceeds 30.7%, 3 axial ratio (AR) of 22.2% 27.5...

"Internet+Education" is an inevitable requirement of teaching reform in colleges and universities. College teachers should follow the steps development times, accelerate innovation education, course be updated from concept, curriculum system reconstruction, content setting, processing And comprehensive reforms evaluation are perfect, so that students can fully feel glamor new system, order to achieve objectives high-quality application talents cultivation, innovative ability.

This paper studies the design of guidance law for nominal trajectory tracking Mars ascent vehicle. First all, flight process is optimized according to needs mission. Secondly, ascending phase, speed loss caused by atmosphere in coasting phase considered, and altitude at apoapsis are corrected. The vehicle guided closed-loop control angle attack sideslip. In addition, problem large error only sliding mode designed. Finally, through numerical simulation, it verified that designed can improve...

This paper proposed a novel large neighborhood search-adaptive genetic algorithm (LNS-AGA) for many-to-many on-orbit repairing mission planning of geosynchronous orbit (GEO) satellites with deadline constraint. In the scenario, several servicing spacecrafts and target are located in GEO orbits which have different inclination, RAAN true anomaly. Each spacecraft need to rendezvous perform missions under limited fuel. The objective is find optimal sequence time every minimize total cost all...