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INTRODUCTION: Secondary functional hypothalamic amenorrhea (SFHA) is common among female athletes, especially in weight-sensitive sports. The aim of this study was to investigate the link between SFHA and neuromuscular performance in elite endurance athletes. METHODS: Sixteen eumenorrheic (EUM) and 14 SFHA athletes from national teams and competitive clubs participated. Methods included gynecologi

A systematic approach to the analysis and design of a class of large dynamical systems is presented. The approach allows decentralized control laws to be designed independently using only local subsystem models. Design can be conducted using standard techniques, including loopshaping based on Nyquist and Popov plots, H methods, and μ-synthesis procedures. The approach is applied to a range of netw

Modern computing systems are often formed by multiple components that interact with each other through the use of shared resources (e.g., CPU, network bandwidth, storage). In this paper, we consider a representative scenario of one such system in the context of an Internet of Things application. The system consists of a network of self-adaptive cameras that share a communication channel, transmitt

In this paper, we introduce the concept of spatially coupled turbo-like codes (SC-TCs) as the spatial coupling of a number of turbo-like code ensembles. In particular, we consider the spatial coupling of parallel concatenated codes, introduced by Berrou et al., and that of serially concatenated codes (SCCs), introduced by Benedetto et al. Furthermore, we propose two extensions of braided convoluti

Hsu–Kasami–Chien (HKC) are a class of cyclic codes that can correct either burst or random errors. This paper studies the maximum burst-correcting capability of HKC codes. A necessary and sufficient condition for a b- burst-correcting cyclic HKC code is given and simplified as a generalized one for Fire codes. An upper bound on the burstcorrecting capability of HKC codes is derived, which improves

Distributed algorithms for solving coupled semidefinite programs (SDPs) commonly require many iterations to converge. They also put high computational demand on the computational agents. In this paper we show that in case the coupled problem has an inherent tree structure, it is possible to devise an efficient distributed algorithm for solving such problems. The proposed algorithm relies on predic

We present a stopping condition to the duality based distributed optimization algorithm presented in [1] when used in a distributed model predictive control (DMPC) context. To enable distributed implementation, the optimization problem has neither terminal constraints nor terminal cost that has become standard in model predictive control (MPC). The developed stopping condition guarantees a prespec

Abstract in UndeterminedSoftware deployment, including both clean installs and updates, is a crucial activity for all software vendors. It starts with a customer's order of a new release and incorporates all steps taken until the customer is satisfied with the deployed product. Using interviews as the main data collection method, we conducted a case study of four companies to discover their softwa

System-theoretical methods are already used for the control of computing systems, but much more can be done exploiting said methods for their design. This requires to express in control-theoretical terms desires and specifications that originate in the computer science do- main, which may not be immediate. It also requires to accept that part of the addressed system be modified, which may pose som

In digital control systems, the state is sampled at given sampling instants and the input is kept constant between two consecutive instants. With the optimal sampling problem, we mean the selection of sampling instants and control inputs, such that a given function of the state and input is minimized. In this paper, we formulate the optimal sampling problem and we derive a necessary condition of t

Stochastic optimal power flow can provide the system operator with adequate strategies for controlling the power flow to maintain secure operation under stochastic parameter variations. One limitation of stochastic optimal power flow has been that only limits on lineflows have been used as stability constraints. In many systems voltage stability and small-signal stability also play an important role i

Lyapunov methods and density functions provide dual characterizations of the solutions of a nonlinear dynamic system. This work exploits the idea of combining both techniques, to yield stability results that are valid for almost all the solutions of the system. Based on the combination of Lyapunov and density functions, analysis methods are proposed for the derivation of almost input-to-state stab

Stochastic optimal power flow can provide the system operator with adequate strategies for controlling the power flow to maintain secure operation under stochastic parameter variations. One limitation of stochastic optimal power flow has been that only line flows have been used as security constraints. In many systems voltage stability and small-signal stability also play an important role in constrai

Fokus på plast i mark och jord: mikroplasters effekt på organismer i jord undersökt med ny teknologi inom jordekologi frågor. De enorma plastutsläppen till naturen är idag ett välkänt problem. Det är också välkänt att plast bryts ner till mindre partiklar med andra effekter, så kallade mikro- och nanoplaster. Allmänheten har visat stort intresse kring plastproblematiken i haven och mycket forskniThis study aims to investigate if micro- and nanoparticles of polystyrene affect microorganisms in soil. This was tested by using microfluidic chips, which are new for investigation of soil ecology questions, providing artificial channels reflecting soil conditions as well as being transparent for seeing real-time interactions. Eight microfluidic chips were made; four were filled with a micro- and

I dagens digitaliserade samhälle möter utgivare och publicister av traditionellt tryckt media stora ekonomiska motgångar vid försäljningen av exempelvis nyhetstidningar eller andra tidskrifter. Således har majoriteten av utläggare idag gjort sina publikationer tillgängliga för läsare online. De digitala intäkterna lyckas dock inte väga upp för de förluster utgivarna lider av den nedåtgående försälIn today's digitized society, publishers of legacy printed media face major financial hardships in the sale of newspapers and other magazines. Thus, most publishers today have made their publications available to readers online. However, digital revenues do not make up for the losses that the publishers suffer from the decreasing sales of printed media. This can in part be attributed to the fa

This manuscript proposes a novel viewpoint on computing systems' modelling. The classical approach is to consider fully functional systems and model them, aiming at closing some external loops to optimise their behaviour. On the contrary, we only model strictly physical phenomena, and realise the rest of the system as a set of controllers. Such an approach permits rigorous assessment of the obtain

Adaptive reservation is a real-time scheduling technique in which each application is associated a fraction of the computational resource (a reservation) that can be dynamically adapted to the varying requirements of the application by using appropriate feedback control algorithms. An adaptive reservation is typically implemented by using an aperiodic server (e.g. sporadic server) algorithm with f

A parametrized model in addition to the control and state-space variables depends on time-independent design parameters, which essentially define a family of models. The goal of parametrized model reduction is to approximate this family of models. In this paper, a reduction method for linear time-invariant (LTI) parametrized models is presented, which constitutes the development of a recently prop

We consider model predictive control (MPC) problems with linear dynamics, polytopic constraints, and quadratic objective. The resulting optimization problem is solved by applying an accelerated gradient method to the dual problem. The focus of this paper is to provide bounds on the number of iterations needed in the algorithm to guarantee a prespecified accuracy of the dual function value and the