Multipath/RFI/modulation study for DRSS-RFI problem: Voice coding and intelligibility testing for a satellite-based air traffic control system

Analog and digital voice coding techniques for application to an L-band satellite-basedair traffic control (ATC) system for over ocean deployment are examined. In addition to performance, the techniques are compared on the basis of cost, size, weight, power consumption, availability, reliability, and multiplexing features. Candidate systems are chosen on the bases of minimum required RF bandwidth and received carrier-to-noise density ratios. A detailed survey of automated and nonautomated intelligibility testing methods and devices is presented and comparisons given. Subjective evaluation of speech system by preference tests is considered. Conclusion and recommendations are developed regarding the selection of the voice system. Likewise, conclusions and recommendations are developed for the appropriate use of intelligibility tests, speech quality measurements, and preference tests with the framework of the proposed ATC system

Juvenile Spondylarthropy in High School Athlete

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Unusual Headaches After a Concussion in a Basketball Player

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Shortness of Breath in a Swimming Athlete

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Nice to value. Unraveling the nexus between management accounting use and financial performance: A quantitative study of SMEs.

This study investigates the intricate relationship between management accounting (MA) practices and financial performance (FP) in small and medium-sized enterprises (SMEs) in Italy and Germany, offering practical insights for practitioners and policy makers. Despite the theoretical benefits of MA practices like cost accounting, budgeting, and key performance indicators, their implementation in SMEs remains limited. Prior research suggests that SMEs often rely on informal control systems due to resource constraints and a lack of familiarity with MA tools. The COVID-19 pandemic and recent European conflicts have stressed the need for robust MA practices to navigate economic volatility and enhance resilience. Using a quantitative approach, data were collected via questionnaires from 238 SMEs in Italy and Germany, targeting chief financial officers, board members, and majority shareholders. The analysis, employing partial least squares structural equation modeling, reveals a significant positive impact of MA practices on FP. Factors such as resource availability, training, and the culture of control play crucial roles in this relationship. These findings underscore the strategic importance of MA in driving organizational performance and highlight the need for SMEs to adopt these practices more comprehensively. This study offers valuable guidance for SME managers in enhancing operational efficiency and strategic decision making. Moreover, it provides policy makers with evidence- based recommendations to support SME growth and resilience through targeted training programs and resource allocation, ensuring a robust framework for economic stability and development

The suitability of the degradation gradient method in arid Namibia

Abstract The Degradation Gradient Method (DGM) is a sophisticated technique for the assessment of range condition. It applies multivariate analyses of herbaceous species data to detect subtle degrees of overgrazing. The suitability of this multivariate method was tested in the central Highland Savanna of Namibia by comparing its results against a univariate analysis of herbaceous data in a simple but robust Range-Unit Model. Despite aridity and topographical heterogeneity, the DGM performed unexpectedly well under these conditions. The relative instability of this dry savanna system favoured the applicability of the DGM by promoting a clear grazing gradient. Using species density data only resulted in an incorrect outcome of the multivariate analysis. The sensitivity of the DGM could be improved by combining density and cover data. Key words: aridity, cover and density data, grazing gradient, ordinations, species response curves, topographical heterogeneity Résumé La méthode du gradient en dégradation (DGM) s'avre une technique sophistiquée dans l'évaluation de la condition des habitats. Elle applique des analyses multivariées aux données sur les espces herbacées afin de déceler mme une mesure subtile de surpturage. L'appropriation de cette méthode multivariée fut expérimentée dans la savane des montagnes centrales de la Namibie travers une comparaison des ré-sultats avec une analyse univariée des données sur les espces herbacées dans un modle Habitat-Unité simple mais robuste. Malgré l'aridité et l'hétérogénéité topographique, le DGM a fonctionné étonnamment bien. L'instabilité relative de ce systme de savane sche a favorisé l'applicabilité du DGM travers la promotion d'un gradient de pturage distinct. L'utilisation des données sur la densité d'espces n'a résulté que dans un aboutissement erroné des analyses multivariées. La sensibilité du DGM pourrait tre améliorée en combinant les données de densité et couverture

A theoretical foundation for multi-scale regular vegetation patterns

Self-organized regular vegetation patterns are widespread and thought to mediate ecosystem functions such as productivity and robustness, but the mechanisms underlying their origin and maintenance remain disputed. Particularly controversial are landscapes of overdispersed (evenly spaced) elements, such as North American Mima mounds, Brazilian murundus, South African heuweltjies, and, famously, Namibian fairy circles. Two competing hypotheses are currently debated. On the one hand, models of scale-dependent feedbacks, whereby plants facilitate neighbours while competing with distant individuals, can reproduce various regular patterns identified in satellite imagery. Owing to deep theoretical roots and apparent generality, scale-dependent feedbacks are widely viewed as a unifying and near-universal principle of regular-pattern formation despite scant empirical evidence. On the other hand, many overdispersed vegetation patterns worldwide have been attributed to subterranean ecosystem engineers such as termites, ants, and rodents. Although potentially consistent with territorial competition, this interpretation has been challenged theoretically and empirically and (unlike scale-dependent feedbacks) lacks a unifying dynamical theory, fuelling scepticism about its plausibility and generality. Here we provide a general theoretical foundation for self-organization of social-insect colonies, validated using data from four continents, which demonstrates that intraspecific competition between territorial animals can generate the large-scale hexagonal regularity of these patterns. However, this mechanism is not mutually exclusive with scale-dependent feedbacks. Using Namib Desert fairy circles as a case study, we present field data showing that these landscapes exhibit multi-scale patterning-previously undocumented in this system-that cannot be explained by either mechanism in isolation. These multi-scale patterns and other emergent properties, such as enhanced resistance to and recovery from drought, instead arise from dynamic interactions in our theoretical framework, which couples both mechanisms. The potentially global extent of animal-induced regularity in vegetation-which can modulate other patterning processes in functionally important ways-emphasizes the need to integrate multiple mechanisms of ecological self-organization