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Background and Purpose. A nontraditional form of exercise recently applied for patients with Parkinson disease (PD) is boxing training. The primary purpose of this case series is to describe the effects of disease severity and duration of boxing training (short term and long term) on changes in balance, mobility, and quality of life for patients with mild or moderate to severe PD. The feasibility and safety of the boxing training program also were assessed. Case Descriptions. Six patients with idiopathic PD attended 24 to 36 boxing training sessions for 12 weeks, with the option of continuing the training for an additional 24 weeks (a seventh patient attended sessions for only 4 weeks). The 90-minute sessions included boxing drills and traditional stretching, strengthening, and endurance exercises. Outcomes were tested at the baseline and after 12, 24, and 36 weeks of boxing sessions (12-, 24-, and 36-week tests). The outcome measures were the Functional Reach Test, Berg Balance Scale, Activities-specific Balance Confidence Scale, Timed 'Up & Go' Test, Six-Minute Walk Test, gait speed, cadence, stride length, step width, activities of daily living and motor examination subscales of the Unified Parkinson Disease Rating Scale, and Parkinson Disease Quality of Life Scale. Outcomes. six patients completed all phases of the case series, showed improvements on at least 5 of the 12 outcome measures over the baseline at the 12-week test, and showed continued improvements at the 24- and 36-week tests. Patients with mild PD typically showed improvements earlier than those with moderate to severe PD. Discussion. Despite the progressive nature of PD, the patients in this case series showed short-term and long-term improvements in balance, gait, activities of daily living, and quality of life after the boxing training program. A longer duration of training was necessary for patients with moderate to severe PD to show maximal training outcomes. The boxing training program was feasible and safe for these patients with PD., Parkinson disease (PD) is a progressive neurodegenerative disorder that is characterized by tremors, postural rigidity, bradykinesia, and postural instability. (1) These motor signs can have detrimental effects on balance, mobility, [...]

This paper presents a systematic comparison of different advanced approaches for motion prediction of vessels for docking scenarios. Therefore, a conventional nonlinear gray-box-model, its extension to a hybrid model using an additional regression neural network (RNN) and a black-box-model only based on an RNN are compared. The optimal hyperparameters are found by grid search. The training and validation data for the different models is collected in full-scale experiments using the solar research vessel Solgenia. The performances of the different prediction models are compared in full-scale scenarios. These can improve advanced control strategies e.g., nonlinear model predictive control (NMPC) or reinforcement learning (RL). This paper explores the question of what the advantages and disadvantages of the different presented prediction approaches are and how they can be used to improve the docking behavior of a vessel. Videos are available under:https://www.htwg-konstanz.de/en/research-and-transfer/institutes-and-laboratories/isd/control-engineering/videos/

This paper proposes a novel nonlinear model predictive control approach for permanent magnet synchronous machines (PMSM). The optimization problem is formulated as a field oriented economic model predictive control (FO-EMPC) problem and therefore a target selector is not necessary. A dq-model of the PMSM with spherical voltage and current constraints is taken into account. A terminal set and a terminal penalty are introduced to mitigate stability and convergence issues with a short prediction horizon. The performance of the proposed control scheme is demonstrated in a simulation study on a personal computer and in a hardware-in-the-loop simulation, which show that the transition time is reduced by more than one order of magnitude with respect to state-of-the-art approaches, especially when the voltage constraint becomes active.

Airborne Wind Energy refers to systems capable of harvesting energy from the wind by flying crosswind patterns with a tethered aircraft. Tuning and validation of flight controllers for AWE systems depends on the availability of reasonable a priori models. In this paper, aerodynamic coefficients are estimated from data gathered from flight test campaign using an efficient multiple experiments model based parameter estimation algorithm. Data fitting is performed using mathematical models based on full six degree of freedom aircraft equations of motion. Several theoretical and practical aspects as well as limitations are highlighted. Finally, both model selection and estimation results are assessed by means of R-squaredvalue and confidence ellipsoids.

Starting in the late 1970s, optimization-based control has built up an impressive track record of successful industrial applications, in particular in the petrochemical and process industries. More recently, optimization methods for automatic control are more and more deployed on so-called embedded hardware to cater for application-specific needs such as guaranteed communication latency, low energy consumption or cost effectiveness. This development greatly broadens the scope of applications to which optimization methods can be applied to sectors such as robotics, automotive, aerospace or power electronics. However, it also poses additional challenges regarding both the algorithmic concepts and their actual implementations for a given computing hardware. This survey paper discusses key challenges for using embedded optimization methods and summarizes their main use cases in current industrial practice. Motivated by this discussion, a number of dedicated embedded optimization algorithms and their actual implementations are reviewed. The presentation is organized according to the mathematical structure of the embedded optimization problem, ranging from convex quadratic programming over more general convex and nonconvex problems to formulations comprising discrete optimization variables.

Dual-phase (DP) steel is the flagship of advanced high-strength steels, which were the first among various candidate alloy systems to find application in weight-reduced automotive components. On the one hand, this is a metallurgical success story: Lean alloying and simple thermomechanical treatment enable use of less material to accomplish more performance while complying with demanding environmental and economic constraints. On the other hand, the enormous literature on DP steels demonstrates the immense complexity of microstructure physics in multiphase alloys: Roughly 50 years after the first reports on ferrite-martensite steels, there are still various open scientific questions. Fortunately, the last decades witnessed enormous advances in the development of enabling experimental and simulation techniques, significantly improving the understanding of DP steels. This review provides a detailed account of these improvements, focusing specifically on (a) microstructure evolution during processing, (b) experimental characterization of micromechanical behavior, and (c) the simulation of mechanical behavior, to highlight the critical unresolved issues and to guide future research efforts.

A recently proposed quadratic programming (QP) solver dedicated to bandstructured optimal control problems as they may arise in the field of model predictive control (MPC) is the dual Newton strategy, as implemented in the publicly available software qpDUNES. Such a structure-exploiting solver is often preferable over the use of condensing for problems with long horizons. In this paper, we propose an effcient and exible algorithm for real-time nonlinear MPC which tries to combine the advantages of the two approaches by means of a block condensing technique. Using a nontrivial benchmarking problem, we show that this approach can improve the performance of the dual Newton strategy by a factor of 10 in terms of total computation times while reducing the delay between state estimate and feedback even further. Additionally, an open-source implementation of the resulting scheme is provided as part of the ACADO code generation tool.

Implementing complex control schemes for a mechanically fragile and expensive system can be a risky undertaking. We can reduce the operational risks by a) identifying regions of state-space where the system is far from critical system bounds and exhibits natural stability, and b) designing a backup controller that keeps the system from crashing if we venture beyond those regions. We propose to maximize the safety-margin of the system's operational bounds, using a stochastic interpretation of the algebraic Lyapunov equation. This technique allows us to find optimally safe open-loop stable setpoints of the system. Next, we propose to add the parameters of a linear output feedback controller as optimization variables, such that setpoint and controller are jointly designed to yield the safest operational regimes. We demonstrate these methods on the application of rotational launch of tethered airplanes for power-generation.

In this paper we present solution approaches for uncertain periodic optimal control problems with invariants that arise e.g., after index reduction of high-index differential algebraic systems. There are two difficulties to be addressed: first, we encounter a redundancy in the periodic boundary constraints which is due to the presence of invariants. And second, we have to deal with the presence of uncertainties. To address the first problem we discuss both a projection and a null-space based reformulation approaches that avoid the redundancies in the constraints. Concerning the uncertainties, we discuss an approximate robust optimal control formulation based on Lyapunov differential equations. Here, the invariants and periodic boundary constraints have to be taken into account, too. We illustrate our techniques by optimizing an open-loop controlled inverted pendulum which is described by index three differential algebraic equations and is affected by unknown forces.

Efficient solution approaches for optimal control problems where the dynamics are described by uncertain differential equations are discussed in the present paper. Problems with uncertainties can be addressed by the robust worst-case formulation. In order to numerically solve the robust counterpart for the optimal control problem several approximation techniques can be employed. In this paper we use an approach based on linearization and solution of Lyapunov differential equations. We exploit the structure of the Lyapunov equation in the optimal control context providing an efficient numerical implementation. The capabilities and computational times of the new approach are demonstrated on two (bio)chemical examples.

In this paper we discuss numerical strategies to find periodic orbits of nonlinear dynamic system. These orbits shall be open-loop stable and robust with respect to bounded disturbances. For this aim, we review and extend existing techniques from the field of reachability analysis and ellipsoidal calculus to compute robust positive invariant tubes for nonlinear dynamic systems. We suggest a conservative approximation strategy for robust stability optimization providing guarantees on the region of attraction. The technique is tested by applying it to an inverted spring pendulum for which robust and open-loop stable orbits exist.

To date, there has been little evidence to suggest the importance of foveal viewing versus peripheral retina viewing when trying to recover from a perturbation. The purposes of this investigation were to (1) determine whether a visual target can be stabilized on the fovea during a perturbation, (2) determine whether stepping responses following a perturbation are influenced by foveal fixation, and (3) compare gaze stability and stepping responses between young and aging adults. Materials/Methods:Ten young adults and 10 aging adults were asked to wear an eye-tracking device linked to a kinematic tracking system during perturbations. Perturbations were delivered under 2 conditions: control(no instructions regarding gaze location were given) and earth-fixed(EF) (subjects were asked to fixate gaze on an EF target). Stepping responses were recorded via force plates. Gaze stability, reported as percent foveal fixation ( FF), was calculated from eye-tracking data. Step latencies (SLs) were computed from force plate data. A 2 ÷ 2 analysis of variance was used to assess statistical significance between groups. For the young and aging adults, linear correlations were made to identify relationships between FF and SL.

Exotherme Reaktionen, wie z. B. Polymerisationsreaktionen in Rührkesselreaktoren, werden vielfach mit Hilfe der Kalorimetrie untersucht und überwacht. Dazu wird üblicherweise die Reaktorwärmebilanz ausgewertet. Für den Fall eines unbekannten oder z. B. auf Grund von Viskositätsänderungen veränderlichen Wärmedurchgangskoeffizienten k kann zusätzlich zu dessen Schätzung die Reaktormantelwärmebilanz herangezogen werden. Bei großen Kühlmitteldurchflüssen durch den Mantel versagt diese Methode allerdings wegen ihrer Rauschempfindlichkeit. Als Alternative wurde in der Literatur die Oszillationskalorimetrie vorgeschlagen, bei der leichte Schwingungen der Reaktortemperatur erzeugt werden. Die in der Literatur vorgestellten Methoden sind allerdings mit dem Nachteil behaftet, dass sie nur im eingeschwungenen Zustand des Systems angewandt werden können. In dieser Arbeit werden vier alternative Auswertungsalgorithmen präsentiert sowie die Frage, welches Anregungssignal eine optimale Schätzung von k ermöglicht.

The electromagnetic nucleon form factors provide constraints on generalized quark distributions. Key results of the study presented here are a strong dependence of the average impact parameter of quarks on their longitudinal momentum fraction, a striking difference in the t dependence of u and d quark contributions to elastic form factors, and an estimate of the orbital angular momentum carried by valence quarks in the nucleon. [Copyright &y& Elsevier]

The Combined Cycle Power Plants (CCPPs) have encountered great diffusion over the last years, due to their high efficiency and low emissions. In the context of the liberalization of the energy market, better performances of the plant control schemes are required. This work deals with the application of the modern multivariable control techniques to the regulation of the steam temperatures of the Heat Recovery Steam Generator (HRSG). Reliable simulations, which witness the capabilities of the adopted Nonlinear Model Predictive Control (NMPC) strategy, have been carried out, relying on the availability of a non linear plant simulator.

Recombinant human thyroid stimulating hormone (rhTSH) for an exogenous stimulation of TSH and consequent thyroglobulin (hTG) synthesis has reinitiated a discussion about the usefulness of diagnostic procedures for the follow-up of differentiated thyroid cancer (DTC).

I review recent progress in the theory of γγ annihilation into meson or baryon pairs at large energy, and of the process γ*γ* → π0 at large photon virtuality. [Copyright &y& Elsevier]

A family of poly[(m-phenylenevinylene)-co-(p-phenylenevinylene)]s, functionalized in the synthetically accessible C-5 position of the meta-disubstituted phenylene rings have been designed and synthesized:  they are essentially poly{(5-alkoxy-m-phenylenevinylene)-co-[(2,5-dioctyloxy-p-phenylene)vinylene]} (PAmPV) derivatives. A range of these PAmPV polymers have been prepared both (1) by the polymerization of O-substituted 5-hydroxyisophthaldehydes and (2) by chemical modifications carried out on polymers bearing reactive groups at the C-5 positions. PAmPV polymers solubilize SWNT bundles in organic solvents by wrapping themselves around the nanotube bundles. PAmPV derivatives which bear tethers or rings form pseudorotaxanes with rings and threads, respectively. The formation of the polypseudorotaxanes has been investigated in solution by NMR and UV/vis spectroscopies, as well as on silicon oxide wafers in the presence of SWNTs by AFM and surface potential microscopy. Wrapping of these functionalized PAmPV polymers around SWNTs results in the grafting of pseudorotaxanes along the walls of the nanotubes in a periodic fashion. The results hold out the prospect of being able to construct arrays of molecular switches and actuators.

AbstractIm ersten Teil der vorliegenden Arbeit, der in der letzten Ausgabe at12(2002) erschienen ist, wurde ein effizientes Verfahren für die Echtzeit-Optimierung in der nichtlinearen prädiktiven Regelung (NMPC) vorgestellt, das sogenannte Echtzeit-Iterations-Schema. Im vorliegenden zweiten Teil wird anhand der Regelung einer Destillationskolonne im Pilotanlagenmaßstab experimentell die Effizienz des vorgestellten Verfahrens bestätigt. In den Experimenten wird die Kolonne zur hochreinen Trennung eines binären Gemisches aus Methanol und n-Propanol verwendet. Das zur Regelung verwendete differentiell-algebraische Systemmodell ist steif und besitzt mehr als 200 Systemzustände. Trotz der hohen Systemordnung ist der Algorithmus in der Lage, auf einem Standard PC alle 20 Sekunden neuoptimierte Steuergrößen zur Verfügung zu stellen. Selbst für sehr große Störungen zeigt der geschlossene Kreis gutes Regelungsverhalten und erfüllt die geforderten Beschränkungen, wobei der notwendige Aufwand zur Einstellung der Reglerparameter minimal ist. Die präsentierten Ergebnisse zeigen, dass die nichtlineare prädiktive Regelung bei Verwendung des vorgestellten Verfahrens auch für große Systeme einsetzbar ist und zu guten Regelungsergebnissen führt.

Abstract.: We study generalized parton distributions in the impact parameter representation, including the case of nonzero skewness . Using Lorentz invariance, and expressing parton distributions in terms of impact parameter dependent wave functions, we investigate in which way they simultaneously describe longitudinal and transverse structure of a fast moving hadron. We compare this information with the one in elastic form factors, in ordinary and in kT-dependent parton distributions.

I discuss recent progress in the theory of exclusive meson production and Compton scattering, focusing on hard-scattering factorization and on dipole formalism.

We investigate the exclusive photoproduction of a heavy timelike photon which decays into a lepton pair, $\gamma p\to \ell^+\!\ell^- p$. This can be seen as the analog of deeply virtual Compton scattering, and we argue that the two processes are complementary for studying generalized parton distributions in the nucleon. In an unpolarized experiment the angular distribution of the leptons readily provides access to the real part of the Compton amplitude. We estimate the possible size of this effect in kinematics where the Compton process should be dominated by quark exchange.

We study the exclusive reactions π−p→ℓ+ℓ−nand π+n→ℓ+ℓ−pin view of possible future experiments with high-intensity pion beams. For large invariant mass of the lepton pair ℓ+ℓ−and small squared momentum transfer to the nucleon these are hard-scattering processes providing access to generalized parton distributions. We estimate the cross section for these reactions, explore their connection with the pion form factor, and discuss the role they can play in improving our understanding of the relevant reaction mechanisms.

Abstract.: We investigate the possibility to constrain the pion distribution amplitude from the transition. For a surprisingly large range in the two photon virtualities we find that the transition form factor is essentially independent of the distribution amplitude. This in turn entails a parameter-free prediction of QCD. The form factors are also briefly discussed. We estimate that experimental studies might be feasible at the existing experiments BaBar, Belle, and CLEO.

We show that the CKM phase 2β+γcan be extracted from measurement of the time dependent rates in the decays B̄0→D(∗)±M∓and B0→D(∗)±M∓, where M=a0, π(1300), b1, a2, π2, ρ3. These channels have a large asymmetry between decays of B̄0and B0into the same final state. Even though the branching ratios are small, their sensitivity to γcan be competitive with decays into D(∗)and (π,ρ,a1).

Ferromagnetic resonance (FMR) techniques are used to investigate superparamagnetic cobalt nanoparticles (NP's) with different crystalline structures and sizes ranging from 4 to 9 nm in diameter. Magnetic contributions from NC shape, crystallographic structure, defects, and surface structure are discussed. An independent-superparamagnetic-grain model is employed to simulate the FMR measurements. The results from both single crystalline and polycrystalline cobalt NP's reveal that a particle's effective anisotropy, and thus its magnetic properties, are extremely sensitive to internal structure as well as overall particle shape. Finally, surface chemical properties were found to yield unique FMR signatures for NP's at low temperatures.

Abstract.: We show that for both quarks and gluons there are eight generalized parton distributions in the proton: four which conserve parton helicity and four which do not. We explain why time reversal invariance does not reduce this number from eight to six, as previously assumed in the literature.

Research described in this paper has developed a classification scheme for the micro-geoparametric parting planes in granites and related rocks. These planes are identified as the planes of weakness along which the granites split or saw the easiest both in the field and at the stoneyard. Together with the analysis of field macro-structural characteristics of the rock mass, the microstruc-tural analysis of the oriented rock samples collected from quarries has led to the identification of two distinct types of parting planes. The first type is related to the preferential orientation of crystals which give rise to partition planes parallel with the crystal boundaries, cleavage or twinning planes. The second microstructure identified is related to the oriented microfissures that are generally attributed to the physical forces and are related to the orientation of in situ rock stresses.

Abstract.: We relate ordinary and skewed parton distributions to soft overlap contributions to elastic form factors and large angle Compton scattering, using light-cone wave functions in a Fock state expansion of the nucleon. With a simple ansatz for the wave functions of the three lowest Fock states we achieve a good description of unpolarised and polarised parton distributions at large x, and of the data for the Dirac form factor and for Compton scattering, both of which can be saturated with soft contributions only. Large angle Compton scattering appears as a good case to investigate the relative importance of soft and hard contributions in exclusive processes which are sensitive to the end point regions of the nucleon wave function.

Abstract: The pomeron model of Donnachie and Landshoff does not conserve the electromagnetic current when applied to diffractive reactions such as electroproduction of a quark-antiquark pair or of a vector meson. We propose a treatment of this problem which ensures a physical behaviour of cross sections in the photoproduction limit and show that it leads to results rather similar to those obtained from two-gluon exchange.

We investigate the production of a quark-antiquark pair in diffractive photon-proton scattering, approximating soft pomeron exchange by the exchange of two nonperturbative gluons. In deep inelastic scattering at HERA, events with two jets and the scattered proton in the final state are predicted to be observable, with an important contribution from charm production. For photoproduction of light quark jets with high transverse momentum we find that both exchanged gluons must have a large invariant mass, so that the cross section is very small, whereas for charm quarks it is quite appreciable. From our calculation we also extract the quark structure function of the pomeron for the scaling variablez no too close to 0 or 1, finding a strong flavour dependence and a behaviour somewhat harder thanz(1-z) for light quarks.

Zusammenfassung Der Einfluß der Temperatur und der Kristallisationsbedingungen auf die Strukturbildung von Dimyristoyllecithin-Monohydrat, Dipalmitoyllecithin-Monohydrat und Distearoyllecithin-Monohydrat wurde durch röntgenografische Messung untersucht und in Form von Gitterparametern ausgewertet.

Zusammenfassung Der Einfluß der Kristallisationsbedingungen und der Temperatur auf die Strukturbildung von wasserfreiem Dimyristoyllecithin, Dipalmitoyllecithin und Distearoyllecithin verschiedener Herkunft wurde röntgenografisch untersucht und in Form von Gitterparametern ausgewertet.

We investigate the prospects of measuring anomalous couplings between gauge bosons at electron-positron-colliders with optimal observables. Such observables are shown to contain all information on the coupling parameters that can be extracted in a given reaction. Their sensitivity to the form factors in the general expressions of the triple gauge verticesWWZ andWWγ, includingCP violating terms and absorptive parts, is calculated in view of LEP2 and the NLC.

In this paper we study two-dimensional Ising spin glasses on a grid with nearest neighbor and periodic boundary interactions, based on a Gaussian bond distribution, and an exterior magnetic field. We show how using a technique called branch and cut, the exact ground states of grids of sizes up to 100×100 can be determined in a moderate amount of computation time, and we report on extensive computational tests. With our method we produce results based on more than 20,000 experiments on the properties of spin glasses whose errors depend only on the assumptions on the model and not on the computational process. This feature is a clear advantage of the method over other, more popular ways to compute the ground state, like Monte Carlo simulation including simulated annealing, evolutionary, and genetic algorithms, that provide only approximate ground states with a degree of accuracy that cannot be determineda priori. Our ground-state energy estimation at zero field is −1.317.

Polynuclear Fe(III) chain compounds with two bridging sulphur atoms show unusual magnetic and spectroscopic properties. The observed antiferromagnetism and the high-spin absorption spectra of the [Fe2S6]6- dimer and of larger clusters up to infinite 1∞[FeS4/2]- chains are explained by an electron density model with different degrees of electron localization. The model is based on extended Hückel theory which includes for infinite systems Bloch functions using the parametrization given in the literature. For the Fe sulphide dimer also unrestricted Hartree-Fock calculations with broken symmetry wavefunctions (UHF-VB) are carried out in order to obtain local spin-density distributions.