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This paper aims to propose Bayesian filtering based on solving the Fokker–Planck equation, to improve the accuracy of filtering in non-Gauss case. Nonlinear filtering plays an important role in many science and engineering fields for estimating the state of dynamic system, but the existing filtering algorithms are mainly used for solving the problem of Gauss system.

Under the Bayesian framework, the time update of this filtering is based on solving Fokker–Planck equation, while the measurement update uses the Bayes formula directly. Therefore, this novel algorithm can be applied to nonlinear, non-Gaussian estimation. To reduce the computational complexity due to standard meshing, an adaptive meshing algorithm proposed which includes the coarse meshing, significant domain determination that is generated using extended Kalman filtering and Chebyshev’s inequality theorem, and value assignment for significant domain. Simulations are conducted on a reentry body tracking problem to demonstrate the effectiveness of this novel algorithm.

In this way, finer grid points can be placed in the regions with high conditional probability density, while the grid points with low conditional probability density can be neglected. The simulation results indicate that the novel algorithm can reduce the computational burden significantly compared to the standard meshing, while achieving similar accuracy.

A novel Bayesian filtering based on solving the Fokker–Planck equation using adaptive meshing is proposed, and the simulations show that algorithm can reduce the computational burden significantly compared to the standard meshing, while achieving similar accuracy.

A novel nonlinear filtering based on solving the Fokker–Planck equation is proposed. The novel algorithm is suitable for non-Gauss system, and can achieve similar accuracy compared to the standard meshing with the significant reduction of computational burden.

The purpose of this paper is to design a global robust and continuous control scheme for the attitude tracking control problem of the reentry vehicle with parameter uncertainties and disturbances.

First, feedback linearization is applied to the model of reentry vehicle, resulting in three independent uncertain subsystems. Then a new second-order time-varying sliding function is proposed, based on which a continuous second-order time-varying sliding mode control (SOTVSMC) law is proposed for each subsystem. The global robustness and convergence performance of the closed-loop reentry vehicle control system under the proposed control law are proved.

Simulation is made for a reentry vehicle through the assumption that there is external disturbance to aerodynamic moment and the aerodynamic parameters as well as the atmospheric density are perturbed. The results verify the validity and robustness of the proposed strategy.

The SOTVSMC attitude controller based on feedback linearization is proposed for the reentry vehicle. The advantages of the proposed SOTVSMC are twofold. First, the global second order sliding mode is established, which implies that the closed-loop system is global robust against matched parameter uncertainties and disturbances in reentry. Second, the chattering problem is significantly alleviated.

The purpose of this paper is to design a disturbance observer-based finite-time global sliding mode control scheme for the attitude tracking control problem of the reentry vehicle with parameter uncertainties and disturbances.

Feedback linearization is first introduced to transform vehicle model into three independent second order uncertain subsystems. Then a finite-time controller (FTC) is proposed for the nominal system on the basis of the homogeneity theory. Thereafter the integral sliding mode method is introduced for the vehicle with disturbances. The finite time convergence is achieved and global robustness is also assured by the combination of finite time control method and integral sliding mode strategy. Furthermore, to improve the attitude angle tracking accuracy a novel finite time disturbance observer (DO) is constructed.

Simulation is made for the reentry vehicle with disturbances involved. And the results show the finite-time convergence, tracking accuracy and robustness of the proposed strategy.

The proposed control strategy has three advantages. First of all it can achieve finite time convergence and avoid singularity. Moreover, it can also realize global robustness. Finally, a new kind of DO is introduced to improve the tracking accuracy.

The purpose of this paper is to propose a combination bank-to-turn control mode with the single moving mass and reaction jet and design the roll control law for the long-range reentry maneuverable warhead.

Based on the dynamics model of this new control mode, the control model of roll channel is converted into a perturbed double-integrator system. The on-off optimal feedback control law is designed on the phase plane formed by Euler angle error and angular velocity error. To weaken the “on-off chattering” that is generated near the origin of the phase-plane and effectively reduce the jet fuel consumption for stability control, an on-off control outer ring and an inner ring are introduced into the phase plane.

This control mode can not only avoid the aerodynamic rudder ablation to improve the efficiency of attitude control, but also reduce the fuel consumption of jet control by using moving mass control. The simulation results indicate that the designed control law can meet the speediness and robustness requirements of the long-range maneuverable warhead controlled by the single moving mass and reaction jet. This measure can also eliminate the on-off chattering effectively.

The new control mode solves some engineering problems of long-range reentry maneuverable warhead controlled by only one actuator. The control mode has a promising prospect in engineering practice.

The paper provides a new control mode and a combination control strategy, and designs an effective control law.

The purpose of this paper is to propose a robust control scheme for near space vehicle's (NSV's) reentry attitude tracking problem under aerodynamic parameter variations and external disturbances.

The robust control scheme is composed of dynamic surface control (DSC) and least squares support vector machines (LS‐SVM). DSC is used to design a nonlinear controller for HSV; then, to increase the robustness and improve the control performance of the controller. LS‐SVM is presented to estimate the lumped uncertainties, including aerodynamic parameter variations and external disturbances. The stability analysis shows that all closed‐loop signals are bounded, with output tracking error and estimate error of LS‐SVM weights exponentially converging to small compacts.

Simulation results demonstrate that the proposed method is effective, leading to promising performance.

First, a robust control scheme composed of DSC and adaptive LS‐SVM is proposed for NSV's reentry attitude tracking problem under aerodynamic parameter variations and external disturbances; second, the proposed method can achieve more favorable tracking performances than conventional dynamic surface control because of employing LS‐SVM to estimate aerodynamic parameter variations and external disturbances.

The purpose of this paper is to present a sliding mode attitude controller for reusable launch vehicle (RLV) which is nonlinear, coupling, and includes uncertain parameters and external disturbances.

A smooth second-order nonsingular terminal sliding mode (NTSM) controller is proposed for RLV in reentry phase. First, a NTSM manifold is proposed for finite-time convergence. Then a smooth second sliding mode controller is designed to establish the sliding mode. An observer is utilized to estimate the lumped disturbance and the estimation result is used for feedforward compensation in the controller.

It is mathematically proved that the proposed sliding mode technique makes the attitude tracking errors converge to zero in finite time and the convergence time is estimated. Simulations are made for RLV through the assumption that aerodynamic parameters and atmospheric density are perturbed. Simulation results demonstrate that the proposed control strategy is effective, leading to promising performance and robustness.

By the proposed controller, the second-order sliding mode is established. The attitude tracking error converges to zero in a finite time. Meanwhile, the chattering is alleviated and a smooth control input is obtained.

The aim of this study is to design a guidance method to generate a smoother and feasible gliding reentry trajectory, a highly constrained problem by formalizing the control variables profile.

A novel accelerated fractional-order particle swarm optimization (FAPSO) method is proposed for velocity updates to design the guidance method for gliding reentry flight vehicles with fixed final energy.

By using the common aero vehicle as a test case for the simulation purpose, it is found that during the initial phase of the longitudinal guidance, there are oscillations in the state parameters which cause to violate the path constraints. For the glide phase of the longitudinal guidance, the path constraints have higher values because of the increase in the atmosphere density.

The violation in the path constraints may compromise the flight vehicle safety, whereas the enforcement assures the flight safety by flying it within the reentry corridor.

An oscillation suppression scheme is proposed by using the FAPSO method during the initial phase of the reentry flight, which smooths the trajectory and enforces the path constraints partially. To enforce the path constraints strictly in the glide phase, ultimately, another scheme by using the FAPSO method is proposed. The simulation results show that the proposed algorithm is efficient to achieve better convergence and accuracy for nominal as well as dispersed conditions.

The purpose of this paper is to make a case for novel and innovative reentry programs focused on women of color and to describe policy recommendations that are necessary to support the sustainability of these programs and in turn the success of the women who participate in them.

A review and analysis of the literature that described job-training opportunities specifically targeted to women exiting jail and the impact on recidivism provided limited information. The authors developed, implemented, and evaluated doula training program for low-income and women of color to determine if birth work could provide stable income and decrease recidivism.

Training low-income formerly incarcerated women to become birth doulas is an innovative strategy to solve employment barriers faced by women reentering communities from jail. Realigning women within communities via birth support to other women also provides culturally relevant and appropriate members of the healthcare team for traditionally vulnerable populations. Doulas are important members of the healthcare workforce and can improve birth outcomes. The authors’ work testing doula training, as a reentry vocational program has been successful in producing 16 culturally relevant and appropriate doulas of color that experienced no re-arrests and to date no program participant has experienced recidivism.

To be successful, the intersections of race, gender, and poverty, for women of color should be considered in the design of reentry programs for individuals exiting jail. The authors’ work provided formerly incarcerated and low-income women of color with vocational skills that provide consistent income, serve as a gateway to the health professions, and increase the numbers of well-trained people of color who serve as providers of care.

This article draws from a qualitative case study with four Black reentry women. Exploring their educational narratives through the framework of Black Feminist Thought, this study reveals that the women enacted their college reentry in three compelling ways: (1) reentry as a response to critical moments, (2) reentry as a strategy for coping with challenges, and (3) reentry as a practical step toward getting their daughters in to college. Cursory reviews of Black women in higher education and representations of Black motherhood contexualize the struggles these and other Black women have faced in getting an education, raising their families, and maintaining a positive image in society.

Over 2 million individuals are incarcerated in the US criminal justice system. More than half of incarcerated Americans are also parents of minors. Parental incarceration can lead to a higher risk of mental illness and enduring trauma in children, as well as other problematic cognitive, developmental, and educational outcomes. Examining parental incarceration through a racial equity lens is critical, as people of color make up 67% of the incarcerated population despite making up only 37% of the US population. Further, gender-related equity issues pose important challenges for families with incarcerated parents. Here, we discuss prison-based psychosocial interventions designed both to build parenting skills and to improve parent well-being within a racial and gender equity lens. We hypothesize that effective services in these areas are essential components in a broad strategy designed to mitigate the potential negative effects suffered by families and children of incarcerated parents of color as a result of their imprisonment.