BIOMECHANICAL SKATING TECHNIQUE ANALYSIS IN BIATHLON

The paper describes examples from a biomechanical research project which is carried out in co-operation between the German Skiing Association/national team in biathlon and the University of Leipzig. The aims of the study were a) to develop a practical procedure to verify dynamic and kinematic skating technique features under typical conditions for the sport, b) to determine valid skating technique characteristics and c) to develop an feedback procedure which can be used in training sessions. The findings have been applied in training during the preparatory phase for the competition season 1999/2000. Biomechanically the study focussed on the determination of an effective temporal coordination of system propulsion impulses being generated by arms/poles and legs/skis

Satisfaction, Restriction and Amalgamation of Constraints in the Framework of M-Adhesive Categories

Application conditions for rules and constraints for graphs are well-known in the theory of graph transformation and have been extended already to M-adhesive transformation systems. According to the literature we distinguish between two kinds of satisfaction for constraints, called general and initial satisfaction of constraints, where initial satisfaction is defined for constraints over an initial object of the base category. Unfortunately, the standard definition of general satisfaction is not compatible with negation in contrast to initial satisfaction. Based on the well-known restriction of objects along type morphisms, we study in this paper restriction and amalgamation of application conditions and constraints together with their solutions. In our main result, we show compatibility of initial satisfaction for positive constraints with restriction and amalgamation, while general satisfaction fails in general. Our main result is based on the compatibility of composition via pushouts with restriction, which is ensured by the horizontal van Kampen property in addition to the vertical one that is generally satisfied in M-adhesive categories.Comment: In Proceedings ACCAT 2012, arXiv:1208.430

Verbreitung und Struktur von Arbeitszeitkonten

Arbeitszeitkonten haben sich in den letzten Jahren massiv verbreitet. Mittlerweile verfügen mindestens 37% der abhängig Beschäftigten über Arbeitszeitkonten. In mindestens 60% der Betriebe sind unterschiedliche Formen von Arbeitszeitkonten eingeführt. Sie revolutionieren das Arbeitszeitsystem und ersetzen das bisherige Leitbild der Normalarbeitszeit durch variable Arbeitszeitformen. Kennzeichnend für die Struktur von Arbeitszeitkonten ist eine Balance von Deregulierung und Reregulierung. Arbeitszeitkonten haben, weil sie zu einem Abbau von bezahlten, vor allem von unbezahlten Überstunden führen, beschäftigungsfördernde Effekte. Zugleich scheinen diese Effekte wieder durch Produktivitätssteigerungen, die ebenfalls aus dem Einsatz von Arbeitszeitkonten resultieren, zumindest teilweise kompensiert zu werden. Schließlich nützen Arbeitszeitkonten aus der Sicht der Beschäftigten den Betrieben und den Beschäftigten gleichermaßen.Working time accounts have recently become very common. At least 37 % of the dependently employed now make use of working time accounts. In at least 60 % of firms various forms of working time accounts have been introduced. Consequently, working time systems have been revolutionized; the previous model of standard working time has been replaced by variable forms of working time. Characteristic for the structure of working time accounts is a balance of deregulation and re-regulation. Since usage of this form of working time leads to an elimination of paid and above all unpaid overtime, working time accounts promotes employment. At the same time, such effects seem again to be compensated by increases in productivity which are also the result of using working time accounts. Finally, from the view of employees, working time accounts benefit equally the firm and the worker

Psychology and economics rather than psychology versus economics: cultural differences but no barriers!

During the last three decades the ascent of behavioral economics clearly helped to bring down artificial disciplinary boundaries between psychology and economics. Noting that behavioral economics seems still under the spell of the rational choice tradition and, indirectly, of behaviorism we scrutinize in an exemplary manner how the development of some kind of cognitive economics might mirror the rise of cognitive psychology without endangering the advantages of the division of labor and of disciplinary specialization

Observation of a quantum Cheshire Cat in a matter wave interferometer experiment

From its very beginning quantum theory has been revealing extraordinary and counter-intuitive phenomena, such as wave-particle duality, Schr\"odinger cats and quantum non-locality. In the study of quantum measurement, a process involving pre- and postselection of quantum ensembles in combination with a weak interaction was found to yield unexpected outcomes. This scheme, usually referred to as "weak measurements", can not only be used as an amplification technique and for minimal disturbing measurements, but also for the exploration of quantum paradoxes. Recently the quantum Cheshire Cat has attracted attention: a quantum system can behave as if a particle and its property (e.g. its polarization) are spatially separated. Up to now most experiments studying weak measurements were done with photonic setups. To reveal the peculiarities of a quantum Cheshire Cat the use of non-zero mass particles is most appealing, since no classical description is possible. Here, we report an experiment using a neutron interferometer to create and observe a purely quantum mechanical Cheshire Cat. The experimental results suggest that the system behaves as if the neutrons went through one beam path, while their spin travelled along the other.Comment: 8 pages, 4 figures and 1 tabl

A method to experimentally clamp leaf water content to defined values to assess its effects on apoplastic pH

Results An experimental setup was developed where LWC is measured by a sensor based on IR-transmission and its signal processed to control a pump which circulates air from the cuvette through a cold trap. Hereby a feedback-loop is formed, which by adjusting vapour pressure deficit (VPD) and consequently leaf transpiration can precisely control LWC. This technique is demonstrated here in a combination with microscopic fluorescence imaging of apoplastic pH (pHapo) as indicated by the excitation ratio of the pH sensitive dye OregonGreen. Initial results indicate that pHapo of the adaxial epidermis of Vicia faba is linearly related to reductions in LWC. Conclusions Using this setup, constant LWC levels, step changes or ramps can be experimentally applied while simultaneously measuring physiological responses. The example experiments demonstrate that bringing LWC under experimental control in this way allows better controlled and more repeatable experiments to probe quantitative relationships between LWC and signaling and regulatory processes

Experimental demonstration of direct path state characterization by strongly measuring weak values in a matter-wave interferometer

A novel method was recently proposed and experimentally realized for characterizing a quantum state by directly measuring its complex probability amplitudes in a particular basis using so-called weak values. Recently Vallone and Dequal showed theoretically that weak measurements are not a necessary condition to determine the weak value [Phys. Rev. Lett. 116, 040502 (2016)]. Here we report a measurement scheme used in a matter-wave interferometric experiment in which the neutron path system's quantum state was characterized via direct measurements using both strong and weak interactions. Experimental evidence is given that strong interactions outperform weak ones. Our results are not limited to neutron interferometry, but can be used in a wide range of quantum systems.Comment: 5 pages, 3 figure

Formal Analysis of Functional Behaviour for Model Transformations Based on Triple Graph Grammars - Extended Version

Triple Graph Grammars (TGGs) are a well-established concept for the specification of model transformations. In previous work we have formalized and analyzed already crucial properties of model transformations like termination, correctness and completeness, but functional behaviour - especially local confluence - is missing up to now. In order to close this gap we generate forward translation rules, which extend standard forward rules by translation attributes keeping track of the elements which have been translated already. In the first main result we show the equivalence of model transformations based on forward resp. forward translation rules. This way, an additional control structure for the forward transformation is not needed. This allows to apply critical pair analysis and corresponding tool support by the tool AGG. However, we do not need general local confluence, because confluence for source graphs not belonging to the source language is not relevant for the functional behaviour of a model transformation. For this reason we only have to analyze a weaker property, called translation confluence. This leads to our second main result, the functional behaviour of model transformations, which is applied to our running example, the model transformation from class diagrams to database models