Visualizing individual dynamics:The case of a talented adolescent

Research on talent and performance development has primarily focused on inter-individual differences. However, research suggests that performance and the underlying determinants change over time, in an individual-specific dynamic way. This chapter illustrates a method to measure, understand, and visualize the performance- and psychosocial dynamics of a talented adolescent athlete. During one season, a talented tennis player filled out an online diary questionnaire twice a week. We visualized the results using R-scripts that we made openly available. This facilitated the interpretation of the athlete’s performance- and psychosocial dynamics, which are influenced by particular events in the athlete’s life. Altogether, the current study provides insight into how the adolescent and the context interact and mutually affect each other in successive iterations

Опыт использования акустического доплеровского измерителя течений (АDCP) в условиях Черного моря

В статье излагается методика проведения измерений Lowered ADCP и обработки первичной информации. При последующей обработке данных широко использовался опыт МГИ НАНУ с аналогичными акустическими измерителями течений в 80-е гг. В результате обобщен опыт применения Lowered ADCP в условиях Черного моря, даны алгоритмы обработки данных, приведены профили абсолютной скорости течений на ряде станций и показано, что предлагаемый подход дает более адекватную качественную и количественную оценку профиля скорости течения, чем известные методы.The methods of measurements with Lowered ADCP and processing of the initial information are presented. During the following data processing the experience of Marine Hydrophysical Institute of NAS of Ukraine with the similar acoustic currents meters in the 80-ies was widely applied. As a result the experience of Lowered ADCP application under the Black Sea conditions is generalized, the algorithms of data processing are given, the profiles of absolute speed of currents are given on the series of stations. It is shown that the proposed approach provides more adequate qualitative and quantitative estimation of the current velocity profile than the known methods do

Visco-elastic energy dissipation in a SiAlON ceramic: quantification and implications for fatigue resistance

During the last decade there has been increasing concern about the fatigue resistance of structural ceramics. In the case of non-transforming monolithic ceramics (as Si3N4, SiC and Al2O3) it appears that damage induced in the wake or at the tip of slowly growing cracks decreases lifetimes under cyclic loads at room temperature, as compared to lifetimes under static loads (1,2). Under cyclic mechanical loading at high temperatures, both lower (3), but also higher lifetimes compared to static loading have been observed in a number of cases (4-10). The extent of the latter, so-called positive, fatigue effect is assumed to be closely related to the volume fraction and viscosity of the amorphous grain boundary residues of the sintering additives. In this letter a method to estimate the visco-elastic response of monolithic ceramics to cyclic loading conditions at high temperatures is proposed. A relation is observed between the visco-elastic energy dissipation measured for two silicon nitride materials, and the structural characteristics of their respective intergranular phases. Some consequences for the fatigue resistance of the tested materials, and of non-transforming monolithic ceramics in general, are discussed.status: publishe

Mechanical fatigue in monolithic non-transforming ceramics

status: publishe

Fatigue resistant silicon nitride ceramics due to anelastic deformation and energy dissipation

To investigate the link between internal friction and fatigue resistance of sintered silicon nitride at elevated temperatures, impulse excitation, torsion pendulum and uniaxial tension-compression tests were performed. At low stress-amplitudes, an internal friction peak is observed and associated with the glass transition of amorphous intergranular phases (IGPs). This peak constitutes a reliable means of energy dissipation for otherwise brittle ceramics. The high amplitude uniaxial tests have revealed a new and much larger internal friction effect than previously could be expected from low amplitude test results. Rheological analysis indicates that the underlying deformation is truly anelastic. Within the investigated stress-amplitude range (30-150 MPa), the damping is shown to increase Linearly with stress-amplitude. As a consequence, energy dissipation in a cyclically loaded component will increase locally at stress concentrations such as crack tips. This results in an increased crack propagation resistance, and explains earlier observations of a positive fatigue effect in sintered silicon nitride at high temperature. (C) 2000 Elsevier Science S.A. All rights reserved.status: publishe

The Multi-Thread Graph Model for Embedded Software Synthesis

Software synthesis is a new approachwhich focuses on the support of real-time embedded software systems without the use of operating-systems. Our software synthesis methodology starts from a concurrent process system specification and tries to automate the mapping of this description onto a single processor. The internal system-level model which captures the embedded software and which is the backbone of our software synthesis methodology, is presented. The model is suited for the encapsulation of fine-grain behavior, support of multiple threads of control (concurrency), synchronization, data communication, hierarchy and timing constraints. Additionally, it is shown how the model is used to address the software scheduling sub-task within our software synthesis methodology. I. INTRODUCTION The target application domain of our software synthesis approach is advanced real-time information processing systems, such as personal communication systems. To make miniaturization possible and to r..