Parallel and distributed Gr\"obner bases computation in JAS

This paper considers parallel Gr\"obner bases algorithms on distributed memory parallel computers with multi-core compute nodes. We summarize three different Gr\"obner bases implementations: shared memory parallel, pure distributed memory parallel and distributed memory combined with shared memory parallelism. The last algorithm, called distributed hybrid, uses only one control communication channel between the master node and the worker nodes and keeps polynomials in shared memory on a node. The polynomials are transported asynchronous to the control-flow of the algorithm in a separate distributed data structure. The implementation is generic and works for all implemented (exact) fields. We present new performance measurements and discuss the performance of the algorithms.Comment: 14 pages, 8 tables, 13 figure

Compression-Responsive Photonic Crystals Based on Fluorine-Containing Polymers

Fluoropolymers represent a unique class of functional polymers due to their various interesting and important properties such as thermal stability, resistance toward chemicals, repellent behaviors, and their low refractive indices in comparison to other polymeric materials. Based on the latter optical property, fluoropolymers are particularly of interest for the preparation of photonic crystals for optical sensing application. Within the present study, photonic crystals were prepared based on core-interlayer-shell particles focusing on fluoropolymers. For particle assembly, the melt-shear organization technique was applied. The high order and refractive index contrast of the individual components of the colloidal crystal structure lead to remarkable reflection colors according to Bragg’s law of diffraction. Due to the special architecture of the particles, consisting of a soft core, a comparably hard interlayer, and again a soft shell, the resulting opal films were capable of changing their shape and domain sizes upon applied pressure, which was accompanied with a (reversible) change of the observed reflection colors as well. By the incorporation of adjustable amounts of UV cross-linking agents into the opal film and subsequent treatment with different UV irradiation times, stable and pressure-sensitive opal films were obtained. It is shown that the present strategy led to (i) pressure-sensitive opal films featuring reversibly switchable reflection colors and (ii) that opal films can be prepared, for which the written pattern—resulting from the compressed particles—could be fixed upon subsequent irradiation with UV light. The herein described novel fluoropolymer-containing photonic crystals, with their pressure-tunable reflection color, are promising candidates in the field of sensing devices and as potential candidates for anti-counterfeiting materials

A Purely Functional Computer Algebra System Embedded in Haskell

We demonstrate how methods in Functional Programming can be used to implement a computer algebra system. As a proof-of-concept, we present the computational-algebra package. It is a computer algebra system implemented as an embedded domain-specific language in Haskell, a purely functional programming language. Utilising methods in functional programming and prominent features of Haskell, this library achieves safety, composability, and correctness at the same time. To demonstrate the advantages of our approach, we have implemented advanced Gr\"{o}bner basis algorithms, such as Faug\`{e}re's $F_4$ and $F_5$, in a composable way.Comment: 16 pages, Accepted to CASC 201

Examining the functionality of peripheral vision: From fundamental understandings to applied sport science

In sports, it is important not only to locate gaze on the right location to utilize the high acuity of foveal vision, but also to attend to other objects in the environment without looking directly at them, accordingly, using peripheral vision. Peripheral vision becomes especially important if, for example, the processing of information from more than one location (e.g. players) is decisive in making accurate decisions. Since such decisions generally must be made under high spatio-temporal demands, costly eye-movements might be advantageously avoided by using peripheral vision for information pick-up from multiple cues. In a series of studies, we aimed to translate the demands found in sports and to investigate the functionality of peripheral vision in a well-controlled experimental paradigm, the multiple object tracking (MOT) task. MOT was implemented in a dual task, along with an additional event-detection task. The present article first presents an overview of sport-specific studies focusing on the functionality of peripheral vision and following, summarizes a series of three published MOT studies. These studies show that peripheral vision is used for simultaneous target monitoring and target-change detection and that visual and attentional demands affect gaze anchoring and change-detection rates. Results also reveal a dysfunctionality of saccades, and further suggest an event- and distance-optimized gaze-anchoring position. In the final portion of this article, we derive specific applications for future sports-specific research. Specifically, we suggest to: (a) use dual-task situations in sport-specific settings, such as monitoring multiple players in soccer and playing a pass at specific moments, (b) investigate the costs of saccades in sports situations with high spatio-temporal demands, as in martial arts, and finally, (c) manipulate attentional and visual demands. For each of these avenues of research, we sketch sports-specific experiments currently being conducted in our research group

Preclinical care of children with traumatic brain injury (TBI)

The fact that injuries caused by accidents are the most common cause of death in children and adolescents in Germany gave rise to the study, which mainly deals with traffic accidents in this group. 200,221 records of emergency-service physicians in Bavaria which cover the period 1995-1999 were analysed with respect to the importance of traumatic brain injury (TBI) in children and adolescents (n = 721 - representing 45.8% of traffic injuries in this age group). The highest incidence of TBI was in summer (34.3%) and in the evening between 16.00 and 18.00 (23.7%). The time taken between accident and arrival of the emergency services was 8.8 ± 3.1 minutes. The preclinical phase lasted 19.3 ± 5.8 minutes. The probability of having an accident with TBI increases with age, the maximum being in the age-range 7 - 14 years (61.6%). Boys (63.2%) were almost twice as susceptible to injury as girls. 36.8% of all cases had no noticeable neurological disorder, 71.1% resulted in a Glasgow Coma Scale (GCS) score of 15. Only 6.3% had most severe neurological disorders, resulting in a GCS score of 3 - 5. Circulation parameters in the form of adapted hypotension were abnormal in only 3.4%, 21.9% of the children had a bradycardia and in 12.3% the blood oxygen saturation fell below 94%. The most frequent intervention was the laying of an i.v. line for infusions. 8.6% of the patients were intubated to allow for ventilation with oxygen. Analgesics were given in 16.7% of the cases. In 84.7% of all cases, the condition was stable and in only 3.3% was a severe deterioration to be observed. The assessments were made using both the National Advisory Committee for Aeronautics (NACA) and Glasgow Coma Scales (GCS). Discrepancies occurred, as a NACA scale of I - III and a GCS score of < 9 was reported in 4.9% of cases. In contrast a NACA scale of IV - VI was reported with a GCS score of 15 in 30% of all cases. TBI symptoms in children are less obvious than in adults, which leads to an age-dependent restriction in implementing therapeutic measures. If these restrictions are a result of misinterpretation of the situation or due to a lack of practice in the preclinical phase, then further training and education of the physicians involved in emergency service work are necessary

Learning different task spaces: how explored density aligns the Quiet Eye.

In the current study, predictions of a theoretical account to the explanation of the Quiet Eye (QE) were investigated. To this end, by manipulating the learning environment, participants (n = 52) learned an underhand throwing task which required to explore task-solution spaces of low vs. high density over a 4-week training phase (640 training trials). Although throwing performance was improved, surprisingly, in posttest and retention test shorter QE durations were found. It is speculated that on a short-time learning scale this effect might be explained by more efficient information processing. Moreover, a trend was observed which suggests that-in line with the inhibition hypothesis-when exploring high-density task-solution spaces longer QE durations are required. However, the rather small effect sizes necessitate further research, which will allow to manipulate the response-effect mappings more directly as, for example, in virtual environments

Sensor-based augmented visual feedback for coordination training in healthy adults: a scoping review.

INTRODUCTION Recent advances in sensor technology demonstrate the potential to enhance training regimes with sensor-based augmented visual feedback training systems for complex movement tasks in sports. Sensorimotor learning requires feedback that guides the learning process towards an optimal solution for the task to be learned, while considering relevant aspects of the individual control system-a process that can be summarized as learning or improving coordination. Sensorimotor learning can be fostered significantly by coaches or therapists providing additional external feedback, which can be incorporated very effectively into the sensorimotor learning process when chosen carefully and administered well. Sensor technology can complement existing measures and therefore improve the feedback provided by the coach or therapist. Ultimately, this sensor technology constitutes a means for autonomous training by giving augmented feedback based on physiological, kinetic, or kinematic data, both in real-time and after training. This requires that the key aspects of feedback administration that prevent excessive guidance can also be successfully automated and incorporated into such electronic devices. METHODS After setting the stage from a computational perspective on motor control and learning, we provided a scoping review of the findings on sensor-based augmented visual feedback in complex sensorimotor tasks occurring in sports-related settings. To increase homogeneity and comparability of the results, we excluded studies focusing on modalities other than visual feedback and employed strict inclusion criteria regarding movement task complexity and health status of participants. RESULTS We reviewed 26 studies that investigated visual feedback in training regimes involving healthy adults aged 18-65. We extracted relevant data regarding the chosen feedback and intervention designs, measured outcomes, and summarized recommendations from the literature. DISCUSSION Based on these findings and the theoretical background on motor learning, we compiled a set of considerations and recommendations for the development and evaluation of future sensor-based augmented feedback systems in the interim. However, high heterogeneity and high risk of bias prevent a meaningful statistical synthesis for an evidence-based feedback design guidance. Stronger study design and reporting guidelines are necessary for future research in the context of complex skill acquisition