Abstract The breaking capacity of a medium voltage (MV) rotary SF6 load break switch (LBS) can be improved by incorporating permanent magnets into the stationary contacts. The magnetic field is intended to blow the switching arc root towards a recessed space at the stationary contacts thereby preventing reignition of the arc after current zero. Making and breaking tests of load current 630 A were performed comparing the switching performance of load break switches equipped without a permanent magnet, with a ferrite and with a neodymium magnet. The impact of different polarity arrangements of the magnets in the three phases is also considered and analysed. In order to understand the arc behaviour caused by the effect of permanent magnet, arcing times and arc voltage were measured and evaluated. The results show that the arc voltage depends on the direction of the electromagnetic force, which is determined by the phase current direction but also by the polarity of the magnets. When the force is directed towards the recessed space at the stationary contacts, the arc voltage is notably higher than in the case where the arc is blown in the opposite direction. The higher arc voltage is a reliable indication that the length of the arc is increased, which significantly reduces the risk of both thermal and dielectric breakdowns after the first current zero. The consequences are noticed first in the reduction of the number of missed current zeroes and second in shorter minimum arcing times. An adverse arrangement of the magnet polarity in the three phases increases the number of missed current zeroes.

ntroduction: Sleep is one of the most important components of overall health. Children with developmental disabilities are at a higher risk of having sleep problems. Purpose: The goal of the present study is to compare sleep patterns of children with developmental disabilities with those of typically developing children. In particular, we examined whether children with an intellectual disability (ID), children with an autism spectrum disorder (ASD) and typically developing children differ in sleep duration, number of night’s waking, screen time (time spent on smartphones, tablets, TV), and outdoor activities. Methods: The sample for this study consisted of 114 children (34 children with ASD, 40 children with ID and 40 typically developing children) aged 2 to 14 years (mean age= 6.4 years, SD = 3.0). Information on children’s sleep patterns was obtained through an online survey completed by the parents of the children. We also collected information regarding the strategies parents use to settle their children for sleep, as well as information regarding screen time and outdoor activities. Results: The results of this study indicate that sleep duration was shortest for children with ID and longest for children without developmental disabilities. Another finding in this study is that screen time and not the outdoor activities was associated with sleep duration. Children with ASD were more likely to use melatonin to fall asleep, while the children with ID were more likely to use medications. Conclusion: Children with ID have shorter sleep duration than children with ASD and typically developing children. Parents have several cognitive and behavioural strategies at their disposal to improve their children’s sleep.

Abstract This paper describes the advantages of using data acquisition systems and software modelling tools to support the assessment and therefore redesign of the existing medium voltage switchgear. A 38kV/630A load break linear puffer (LP) will be used as an example for this study. In house testing was conducted to capture important design parameters of the switch such as displacement, velocity of mechanical parts and gas pressure using various sensors and three different measurement setups. The first setup, which is primarily intended for no-load measurements, consists of a DAQ system equipped with different types of sensors - two rotational encoders, three laser-based distance sensors, six pressure sensors, contact separation measurement, and a high-speed camera integrated and synchronized with the measurement system. The second and third setups, which are suitable both for no-load and on-load measurements, are based on state-of-the-art DAQ systems, which use three piezo-electric based pressure sensors, two fibre-optic based pressure sensors, three laser-based distance sensors and a high speed camera synchronized with the measurement system. The data acquired by the measurement systems is used in combination with an in-house developed simulation software HV CB Simulation, which enables simulating and predicting various variables of switching devices. Moreover, high speed camera videos analysed with both commercial and in-house developed image processing software, visualize and reveal many otherwise inaccessible occurrences. In addition to a comprehensive analysis of the proposed data acquisition and simulation setups, three design improvements in the linear puffer design - increase of the opening speed, removal of the flexible conductors and the length increase of the puffer cylinder - are presented and discussed in this paper.

With an exclusive diet of hard-shelled mollusks, the black drum fish (Pogonias Cromis) exhibits one of the highest bite forces among extant animals. Here we present a systematic microstructural, chemical, crystallographic, and mechanical analysis of the black drum teeth to understand the structural basis for achieving the molluscivorous requirements. At the material level, the outermost enameloid shows higher modulus (Er = 126.9 ± 16.3 GPa, H = 5.0 ± 1.4 GPa) than other reported fish teeth, which is attributed to the stiffening effect of Zn and F doping in apatite crystals and the preferential co-alignment of crystallographic c-axes and enameloid rods along the biting direction. The high fracture toughness (Kc = 1.12 MPa•m1/2) near outer enameloid also promotes local yielding instead of fracture during crushing contact with mollusk shells. At the individual-tooth scale, the molar-like teeth, high density of dentin tubules, enlarged pulp chamber, and specialized dentin-bone connection, all contribute to the functional requirements, including confinement of contact compressive stress in the stiff enameloid, enhanced energy absorption in the compliant dentin, and controlled failure of tooth-bone composite under excessive loads. These results show that the multi-scale structures of black drum teeth are adapted to feed on mollusks. STATEMENT OF SIGNIFICANCE: : The black drum fish feeds on hard-shelled mollusks, which requires strong, tough, and wear-resistant teeth. This study presents a comprehensive multiscale material and mechanical analysis of the black drum teeth in achieving such remarkable biological function. At microscale, the fluoride- and zinc-doped apatite crystallites in the outer enameloid region are aligned perpendicular to the occlusal surface, representing as one of the stiffest biomineralized materials found in nature, while these apatite crystals are arranged into intertwisted rods with crystallographic misorientation in the inner enameloid region for increased crack resistance and toughness. At macroscale, the molariform geometry, the two-layer design based on the outer enameloid and inner dentin, enlarged pulp chamber and the underlying strong bony toothplate work synergistically to contribute to the teeth's crushing resistance.

Aims: We studied the syntaxonomic position, biodiversity, ecological features, nature conservation value and current status of dry grasslands investigated by Josias Braun-Blanquet more than 60 years ago. Study area: Inner-alpine valleys of Austria. Methods: We sampled 67 plots of 10 m2, following the standardized EDGG methodology. We subjected our plots to an unsupervised classification with the modified TWINSPAN algorithm and interpreted the branches of the dendrogram syntaxonomically. Biodiversity, structural and ecological characteristics of the resulting vegetation units at association and order level were compared by ANOVAs. Results: All the examined grasslands belong to the class Festuco-Brometea. From ten distinguished clusters, we could assign four clusters to validly published associations, while the remaining six clusters were named tentatively. We classified them into three orders: Stipo-Festucetalia pallentis (Armerio elongatae-Potentilletum arenariae, Phleo phleoidis-Pulsatilletum nigricantis, Medicago minima-Melica ciliata community, Koelerio pyramidatae-Teucrietum montani), Festucetalia valesiacae (Sempervivum tectorum-Festuca valesiaca community); Brachypodietalia pinnati (Astragalo onobrychidis-Brometum erecti, Agrostis capillaris-Avenula adsurgens community, Anthericum ramosum-Brachypodium pinnatum community, Ranunculus bulbosus-Festuca rubra community, Carduus defloratus-Brachypodium pinnatum community). Conclusions: The ten distinguished dry grassland communities of the Austrian inner-alpine valleys differ in their ecological affinities as well as their vascular plant, bryophyte and lichen diversity. We point out their high nature conservation importance, as each of them presents a unique habitat of high value. Taxonomic reference: Names of vascular plants, bryophytes and lichens follow Fischer et al. (2008), Frahm and Frey (2004) and Nimis et al. (2018), respectively. Syntaxonomic reference: Names of orders and classes follow Mucina et al. (2016), references for associations and alliances are given in the text. Abbreviations: ANOVA = analysis of variance; DCA: detrended correspondence analyses; EDGG: Eurasian Dry Grassland Group; EIV: ecological indicator value; FL: Fließ; GR: Griffen; GU: Gulsen; KA: Kaunerberg; LA: Laudegg castle in Ladis; MA: Marin; NM: Neumarkt in der Steiermark; OM: Obermauern; PÖ: Pöls; PU: Puxer Loch; TWINSPAN = Two-way indicator species analysis; ZS: Zinizachspitze.

Architectural design decisions, such as service deployment and composition, plant layout synthesis, or production planning, are an indispensable and overarching part of an industrial manufacturing system design. In the fourth industrial revolution (Industry 4.0), frequent production changes trigger their synthesis, and preferably optimization. Yet, knowledge on architecture synthesis and optimization has been scattered around other domains, such as generic software engineering. We take a step towards synthesizing current knowledge on architectural design decisions in Industry 4.0. We developed a taxonomy describing architectural models, design decisions, and optimization possibilities. The developed taxonomy serves as a guideline for comparing different possibilities (e.g., application of different optimization algorithms) and selecting appropriate ones for a given context. Furthermore, we reviewed and mapped 30 relevant research works to the taxonomy, identifying research trends and gaps. We discuss interesting, and yet uncovered topics that emerged from our review.

– The aims of this paper were to describe seasonal changes in the qualitative and quantitative composition of diatom taxa and the potential application of benthic diatoms for ecological status evaluation. Diatom indices (IPS and TI) were calculated from data from three different locations along a longitudinal profile of the Bunica, a small karstic river in Bosnia and Herzegovina. A total of 147 taxa were recorded in 12 samples. The most common taxa were Meridion circulare (Greville) C.Agardh and Ulnaria ulna (Nitzsch) Compère. Physical and chemical analyses showed low concentrations of nutrients, good oxygenation, typical pH for carbonate bed/origin and generally oligotrophic conditions and high ecological status. All sites had similar physico-chemical conditions and there were only few seasonal differences. Ordination of the diatom data showed that samples showed neither longitudinal nor seasonal patterns. Median value for IPS (16.8) and for TI (7.3) can be possible ‘‘expected’’ values for ecological status assessment for small karstic rivers in the Mediterranean region. We propose the use of the phytobenthos Intercalibration Common Metric (pICM - an index that combines the IPS and TI) as a national metric for countries developing WFD diatom methods at a late stage. One situation is described, and a solution, which is potentially transferable to other locations in Bosnia and Herzegovina and also to other countries facing similar challenges.

Introduction: This research aimed to determine the impact of horseback riding on the balance ability of first-grade students. Material and methods: Fifty-eight students were divided into two sub-groups: twenty-eight riders and thirty non-riders. The subtest of balance is composed of nine items which were grouped into five variables: Total balance, Static balance, Dynamic balance, and Open and Closed eyes balance. The Mann-Whitney U test was used to determine the significance of the difference between the groups, and the strength of the effect of intergroup differences was determined using the Cohen criteria. Results: The results showed that there were statistically significant differences between groups in Total balance, Static, and Balance with closed eyes. Cohen's criterion indicates that there was a strong effect of intergroup differences in performance demanding balance tasks of 7-year-old children. Conclusion: It can be observed that horseback riding has the effect of reducing the difference between the maximum and minimum balance points by enhancing competencies at the minimum level.

Aim of study: This research aims to determine if there are statistically significant differences among provenances of silver fir (Abies alba Mill.) as one of the most important tree species in Bosnia and Herzegovina, to choose a provenance with the best productivity for further silvicultural activities of silver fir in the country. Material and methods: The height and diameter at breast height were measured, and the basal area and volume of silver fir trees were calculated in the silver fir provenance test. The test contains nine provenances from Bosnia and Hezegovina and was launched in 1991, with 5-year-old seedlings (3+2). The data were collected in 2013. Main results: Variance analysis for all traits showed statistically significant differences among provenances. Average breast height diameter in 27-year-old plants for all provenances amounted to 11.0 cm, average height 8.4 m, average basal area 0.010342 m, and average volume 0.070845 m Highlights: The research results confirmed the existence of variability among silver fir provenances in Bosnia and Herzegovina, considering the morphological indicators. Provenance Bosanski Petrovac showed the highest values of all traits, which implies it is the best provenance for the further activities on seed collecting and producing planting material for afforestation in Bosnia and Herzegovina.

A temática fechamento de escola do campo tem sido fortemente discutida nos últimos anos em vários trabalhos científicos, sendo também fator de preocupação por parte das comunidades localizadas em área rural. Este artigo analisa a política de municipalização do ensino fundamental e de nucleação de escolas, indicando que tal política é o principal motivador do fechamento de milhares de escolas do campo no Brasil e de dezenas de escolas no Município de Passos Maia. Além disso, está elaboração apresenta dados sobre as escolas que foram fechadas no Município de Passos Maia e aponta os impactos negativos que a comunidade Conquista de Sepé obteve ao ser fechada sua escola local. Conclui-se, dessa forma, que fechar as Escolas do Campo provoca a destituição da organização social e da vivência comunitária. Nesta direção é que se localiza a afirmação de que Escola do Campo é “vida na comunidade”, por compreende-se que o fechamento/extinção de escolas do campo leva ao fechamento/extinção das comunidades rurais.  Como instrumentos metodológicos, para a elaboração do trabalho, foram utilizados estudo bibliográfico e entrevistas.

To shift the paradigm towards Industry 4.0, maritime domain aims to utilize shared situational awareness (SSA) amongst vessels. SSA entails sharing various heterogeneous information, depending on the context and use case at hand, and no single wireless technology is equally suitable for all uses. Moreover, different vessels are equipped with different hardware and have different communication capabilities, as well as communication needs. To enable SSA regardless of the vessel’s communication capabilities and context, we propose a multimodal network architecture that utilizes all of the network interfaces on a vessel, including multiple IEEE 802.11 interfaces, and automatically bootstraps the communication transparently to the applications, making the entire communication system environment-aware, service-driven, and technology-agnostic. This paper presents the design, implementation, and evaluation of the proposed network architecture which introduces virtually no additional delays as compared to the Linux communication stack, automates communication bootstrapping, and uses a novel application-network integration concept that enables application-aware networks, as well as network-aware applications. The evaluation was conducted for several IEEE 802.11 flavors. Although inspired by SSA for vessels, the proposed architecture incorporates several concepts applicable in other domains. It is modular enough to support existing, as well as emerging communication technologies.