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Refugees and forced migrants are particularly susceptible to trauma-related disorders, due exposure to traumatic events before, during or after displacement. In trauma therapy, the concept of psychological stabilization refers to the improvement of a patient’s capacity to manage symptoms and emotions associated with traumatic experiences. While exposure-based therapies are widely recommended for treating posttraumatic stress disorder (PTSD), stabilizing interventions may offer a valuable alternative, particularly given the unique challenges in refugee care. This scoping review aims to provide a comprehensive overview of stabilizing, non exposure-based interventions for traumatized refugees A systematic search identified 31 relevant studies featuring diverse interventions, settings, and outcomes. Most studies showed a significant reduction in PTSD symptoms compared to waitlist (six studies), treatment as usual (three studies) and pre-post analyses (nine studies), though nine studies found no difference between intervention and comparison group. Notably, two studies found the stabilizing approach less effective than the comparison group, and two reported no symptom reduction in pre-post analysis. Heterogenity among the examined interventions as well as living conditions was high and limited the generizability of the results. Further studies should take these environmental factors into consideration.
High-power lasers are vital for particle acceleration, imaging, fusion and materials processing, requiring precise control and high-energy delivery. Laser plasma accelerators (LPAs) demand laser positional stability at focus to ensure consistent electron beams in applications such as X-ray free-electron lasers and high-energy colliders. Achieving this stability is especially challenging for the low-repetition-rate lasers in current LPAs. We present a machine learning method that predicts and corrects laser pointing instabilities in real-time using a high-frequency pilot beam. By preemptively adjusting a correction mirror, this approach overcomes traditional feedback limits. Demonstrated on the BELLA petawatt laser operating at the terawatt level (30 mJ amplification), our method achieved root mean square pointing stabilization of 0.34 and 0.59 $\unicode{x3bc} \mathrm{rad}$ in the x and y directions, reducing jitter by 65% and 47%, respectively. This is the first successful application of predictive control for shot-to-shot stabilization in low-repetition-rate laser systems, paving the way for full-energy petawatt lasers and transformative advances across science, industry and security.
Traditional wavefront control in high-energy, high-intensity laser systems usually lacks real-time capability, failing to address dynamic aberrations. This limits experimental accuracy due to shot-to-shot fluctuations and necessitates long cool-down phases to mitigate thermal effects, particularly as higher repetition rates become essential, for example, in inertial fusion research. This paper details the development and implementation of a real-time capable adaptive optics system at the Apollon laser facility. Inspired by astronomical adaptive optics, the system uses a fiber-coupled 905 nm laser diode as a pilot beam that allows for spectral separation, bypassing the constraints of pulsed lasers. A graphics processing unit-based controller, built on the open-source Compute And Control for Adaptive Optics framework, manages a loop comprising a bimorph deformable mirror and a high-speed Shack–Hartmann sensor. Initial tests showed excellent stability and effective aberration correction. However, integration into the Apollon laser revealed critical challenges unique to the laser environment that must be resolved to ensure safe operation with amplified shots.
In a smoothly bounded domain $\Omega \subset \mathbb{R}^n$, $n\ge 1$, this manuscript considers the homogeneous Neumann boundary problem for the chemotaxis system
\begin{eqnarray*} \left \{ \begin{array}{l} u_t = \Delta u - \nabla \cdot (u\nabla v), \\[5pt] v_t = \Delta v + u - \alpha uv, \end{array} \right . \end{eqnarray*}
with parameter $\alpha \gt 0$ and with coincident production and uptake of attractants, as recently emphasized by Dallaston et al. as relevant for the understanding of T-cell dynamics.
It is shown that there exists $\delta _\star =\delta _\star (n)\gt 0$ such that for any given $\alpha \ge \frac{1}{\delta _\star }$ and for any suitably regular initial data satisfying $v(\cdot, 0)\le \delta _\star$, this problem admits a unique classical solution that stabilizes to the constant equilibrium $(\frac{1}{|\Omega |}\int _\Omega u(\cdot, 0), \, \frac{1}{\alpha })$ in the large time limit.
Four approaches to concept formation are particularly fruitful for the endeavor of this book. These are Adrian Cussins’ theory of cognitive trails, Serge Moscovici’s and Ivana Marková’s closely interconnected theories of social representations and dialogicality, Ed Hutchins’ theory of conceptual blending by material anchors, and Nancy Nersessian’s theory of model-based reasoning. An examination of these approaches yields the following initial lessons: (1) longitudinal character of concept formation, (2) materiality of concept formation, (3) societal and dialogical embeddedness of concept formation, (4) centrality of tensions and contradictions in concept formation, and (5) importance of change and future-orientation in concept formation in the wild. These first lessons are still embryonic. They draw on cognitive and social-psychological approaches that are not systematically built on materialist dialectics.
Recurrent gestures are stabilized forms that embody a practical knowledge of dealing with different communicative, interactional, cognitive, and affective tasks. They are often derived from practical actions and engage in semantic and pragmatic meaning-making. They occupy a place between spontaneous (singular) gestures and emblems on a continuum of increasing stabilization. The chapter reconstructs the beginnings of research on recurrent gestures and illuminates different disciplinary perspectives that have explored processes of their emergence and stabilization, as well as facets of their communicative potential. The early days of recurrent-gesture research focused on the identification of single specimens and on the refinement of descriptive methods. In recent years, their role in self-individuation, their social role, and their relationship to signs of sign language have become a focus of interest. The chapter explores the individual, the linguistic, and the cultural side of recurrent gestures. Recurrent gestures are introduced as sedimented individual and social practices, as revealing the linguistic potential of gestures, and as a type that forms culturally shared repertoires.
We consider Gaussian approximation in a variant of the classical Johnson–Mehl birth–growth model with random growth speed. Seeds appear randomly in $\mathbb{R}^d$ at random times and start growing instantaneously in all directions with a random speed. The locations, birth times, and growth speeds of the seeds are given by a Poisson process. Under suitable conditions on the random growth speed, the time distribution, and a weight function $h\;:\;\mathbb{R}^d \times [0,\infty) \to [0,\infty)$, we prove a Gaussian convergence of the sum of the weights at the exposed points, which are those seeds in the model that are not covered at the time of their birth. Such models have previously been considered, albeit with fixed growth speed. Moreover, using recent results on stabilization regions, we provide non-asymptotic bounds on the distance between the normalized sum of weights and a standard Gaussian random variable in the Wasserstein and Kolmogorov metrics.
Loess is a collapsible soil; when it collapses, it can cause significant damage to structures built on it. Improvement in the stability and strength performance of loess is necessary to meet engineering needs. In the present study, the effects on the physical-chemical and rheological characteristics of Ghardaïa loess of adding bentonite and lime (southern Algeria) were examined. Rheological characterization of suspensions was implemented to assess the mechanical sensitivity of the bonds and the structural inter-particle resistance to both the chemical effect and mechanical impact. By analyzing the viscosity results and the evolution of the rheological parameters, the improvements needed in terms of the resistance characteristics of the loess-bentonite and loess-lime mixtures were evaluated and confirmed. The loess physical sensitivity was examined through grain-size distribution and plasticity properties. The pH and electrical conductivity of the mixtures were also used to explore structural modifications. Physical test results showed that introduction of the additives changed the loess texture and improved the plasticity of mixtures. Chemical examination (via change in pH and electrical conductivity) revealed the structural changes in the mixtures studied. Rheological test results showed that increasing concentrations of bentonite and lime improves the mechanical strength and increased the yield stress, consistency, and viscosity of the suspensions. The creation of cement interactions between mixture particles explained the increase in those parameters. Hydration, agglomeration, and inter-particle flocculation induced by the additives promoted these interactions. The experimental results led to the conclusion that bentonite and lime may represent an effective means to improve the performance in terms of preventing loess collapse and to increase its resistance to mechanical impact. The results presented in the present study may provide a geotechnical and rheological working database for the control and treatment of loess collapse and landslides in the region under study. Technical data related to loess may, therefore, be beneficial in terms of civil engineering, public works, hydraulics, and the manufacture of construction materials.
Results of stabilization for the higher order of the Kadomtsev-Petviashvili equation are presented in this manuscript. Precisely, we prove with two different approaches that under the presence of a damping mechanism and an internal delay term (anti-damping) the solutions of the Kawahara–Kadomtsev–Petviashvili equation are locally and globally exponentially stable. The main novelty of this work is that we present the optimal constant, as well as the minimal time, that ensures that the energy associated with this system goes to zero exponentially.
The next generation of high-power lasers enables repetition of experiments at orders of magnitude higher frequency than what was possible using the prior generation. Facilities requiring human intervention between laser repetitions need to adapt in order to keep pace with the new laser technology. A distributed networked control system can enable laboratory-wide automation and feedback control loops. These higher-repetition-rate experiments will create enormous quantities of data. A consistent approach to managing data can increase data accessibility, reduce repetitive data-software development and mitigate poorly organized metadata. An opportunity arises to share knowledge of improvements to control and data infrastructure currently being undertaken. We compare platforms and approaches to state-of-the-art control systems and data management at high-power laser facilities, and we illustrate these topics with case studies from our community.
Signal-to-interference-plus-noise ratio (SINR) percolation is an infinite-range dependent variant of continuum percolation modeling connections in a telecommunication network. Unlike in earlier works, in the present paper the transmitted signal powers of the devices of the network are assumed random, independent and identically distributed, and possibly unbounded. Additionally, we assume that the devices form a stationary Cox point process, i.e., a Poisson point process with stationary random intensity measure, in two or more dimensions. We present the following main results. First, under suitable moment conditions on the signal powers and the intensity measure, there is percolation in the SINR graph given that the device density is high and interferences are sufficiently reduced, but not vanishing. Second, if the interference cancellation factor $\gamma$ and the SINR threshold $\tau$ satisfy $\gamma \geq 1/(2\tau)$, then there is no percolation for any intensity parameter. Third, in the case of a Poisson point process with constant powers, for any intensity parameter that is supercritical for the underlying Gilbert graph, the SINR graph also percolates with some small but positive interference cancellation factor.
Inverted pendulum systems (IPSs) are mostly used to demonstrate the control rules for keeping the pendulum at a balanced upright position due to a slight force applied to the cart system. This paper presents an application for nonlinear control of an x-z type IPS by using a proportional-integral-derivative (PID) controller with newly established evolutionary tuning method Lightning Search Algorithm (LSA). A single, double and triple PID controller system is tested with the conventional and the self-tuning controllers to get a better understanding of the performance of the given system. The mathematical modelling of the x-z type IPS, the theoretical explanation of the LSA and the simulation analysis of the x-z type IPS is put forward entirely. The LSA algorithm solves the optimization problem of PID controller in an evolutionary way. The most effective way of making comparisons is evaluating the performance results with a well-known optimization technique or with the previous accepted results. We have compared the system’s performance with particle swarm optimization and with a classical control study in the literature. According to the simulation results, LSA-tuned PID controller has the ability to decrease the overshoot better than the conventional-tuned controllers. Finally, it can be concluded that the LSA-supported PID can better stabilize the pendulum angle and track the reference better for non-disturbed and the slightly disturbed systems.
We prove an almost sure central limit theorem on the Poisson space, which is perfectly tailored for stabilizing functionals arising in stochastic geometry. As a consequence, we provide almost sure central limit theorems for (i) the total edge length of the k-nearest neighbors random graph, (ii) the clique count in random geometric graphs, and (iii) the volume of the set approximation via the Poisson–Voronoi tessellation.
The purpose of this paper is to design a stabilizing controller for a car with n connected trailers. The proposed control algorithm is constructed on the Lyapunov theory. In this paper, the purpose of navigating the system toward the desired point considering the slip phenomenon as a main source of uncertainty is analyzed. First mathematical models are presented. Then, a stabilizing control approach based on the Lyapunov theory is presented. Subsequently, an uncertainty estimator is taken into account to overcome the wheel slip effects. Obtained results show the convergence properties of the proposed control algorithm against the slip phenomenon.
We observe a realization of a stationary weighted Voronoi tessellation of the d-dimensional Euclidean space within a bounded observation window. Given a geometric characteristic of the typical cell, we use the minus-sampling technique to construct an unbiased estimator of the average value of this geometric characteristic. Under mild conditions on the weights of the cells, we establish variance asymptotics and the asymptotic normality of the unbiased estimator as the observation window tends to the whole space. Moreover, weak consistency is shown for this estimator.
Chapter 6 deals with the crisis year of 1923 and examines the German Right’s response to the hyperinflation of 1922–23, the Franco-Belgian occupation of the Ruhr, the increasingly palpable fear of Bolshevism, and threat of Bavaria’s secession from the Reich. After a discussion of the DNVP’s relationship to the Cuno government that assumed office in November 1922, the chapter takes a particularly close look at its opposition to the Stresemann cabinet that assumed power at the height of the crisis in August 1923. Following the termination of passive resistance in the Ruhr, many DNVP leaders began to embrace the idea of a “national dictatorship” under the tutelage of the army commander-in-chief Hans von Seeckt as the only way out of the crisis in which Germany found itself. But movement in this direction was cut short not only by Seeckt’s ambivalence but more importantly by Hitler’s abortive “Beer Hall Putsch” in Munich. As the Stresemann government moved to consolidate its position in the aftermath of the putsch, any chance of replacing the Weimar Republic with a more authoritarian system of government had vanished.
Chapter 7 examines the DNVP’s reaction to the stabilization of Germany’s republican system under the auspices of a new government formed by the Center Party’s Wilhelm Marx in January 1924. In the campaign for the May 1924 Reichstag elections, the DNVP not only did its best to dissociate itself from the anti-social consequences of stabilization, but moved racism and antisemitism to the forefront of its campaign in an attempt to preempt attacks from the racists that had bolted the party in 1922. The result was a stunning victory at the polls that made its delegation the largest in the Reichstag. But with success comes responsibility, and the DNVP was suddenly faced with the task of voting for the Dawes Plan, a plan that in the campaign it had denounced as a “second Versailles.” In the decisive vote in August 1924, the Nationalist delegation to the Reichstag split right down the middle in a dramatic turn of events that only highlighted how deeply divided the DNVP was as it faced the prospect of governmental responsibility.
The United States (US) and Caribbean regions remain vulnerable to the impact of severe tropical storms, hurricanes, and typhoons. In 2017, a series of hurricanes posed threats to residents living in inland and coastal communities as well as on islands isolated from the US mainland. Harvey, Irma, Jose, and Maria caused catastrophic infrastructure damage, resulting in a loss of electrical power and communications due to damaged or downed utility poles, cell towers, and transmission lines. Critical services were inoperable for many months. Emergency managers are public officials who are accountable to both political leaders and the citizens. During disaster events, emergency managers must prioritize areas of effort, manage personnel, and communicate with stakeholders to address critical infrastructure interdependences. Essential lifeline services (eg, energy and communications) were inoperable for many months, which led to increased attention from policy-makers, media, and the public.
This paper addresses the systematic approach to design formation control for kinematic model of unicycle-type nonholonomic mobile robots. These robots are difficult to stabilize and control due to their nonintegrable constraints. The difficulty of control increases when there is a requirement to control a cluster of nonholonomic mobile robots in specific formation. In this paper, the design of the control scheme is presented in a three-step process. First, a robust state-feedback point-to-point stabilization control is designed using sliding mode control. In the second step, the controller is modified so as to address the tracking problem for time-varying reference trajectories. The proposed control scheme is shown to provide the desired robustness properties in the presence of the parameter variation, in the region of interest. Finally, in third step, tracking problem of a single nonholonomic mobile robot extends to formation control for a group of mobile robots in the leader–follower scenario using integral terminal- based sliding mode control augmented with stabilizing control. Starting with the transformation of the mathematical model of robots, the proposed controller ensures that the robots maintain a constant distance between each other to avoid collision. The main problem with the proposed controller is that it requires all states specially velocities. Therefore, the state-feedback control scheme is then extended to output feedback by incorporating a highgain observer. With the help of Lyapunov analysis and appropriate simulations, it is shown that the proposed output-feedback control scheme achieves the required control objectives. Furthermore, the closed loop system trajectories reach to desired equilibrium point in finite time while maintaining the special pattern.