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Low flow rate is one of the primary disadvantages of Roots pumps when they are applied in hydrogen fuel cell vehicles. A novel profile for Roots pumps was developed in this paper to increase the working volume and reduce the internal leakage. The available range of the design parameters of the Roots pump with the new profile was determined analytically, and an improvement in the working volume was validated. The flow dynamics inside the traditional and new pumps were investigated by experiments and numerical simulations. The analytical results indicated that the maximum area utilization of the new profile was approximately 10.4% higher than that of the traditional profile at the same lobe number. The numerical results demonstrated the superiority of the proposed profile in high flow rate and sealing. The tip concentric arcs of the new profile reduced the internal leakage via the radial gap. The characteristic of multipoint meshing within a certain range of rotational angles reduced the interlobe leakage. [Display omitted] • A novel rotor profile for Roots pumps applied in FCVs was developed. • The new profile had an obvious improvement on the area utilization. • The Roots pump with the novel profile can reduce internal leakage. [ABSTRACT FROM AUTHOR]

The device miniaturization technology made possible to integrate large density of transistors in a chip to produce high computation facility. At the same time, it demands an efficient thermal management technique to handle enormous power dissipation during high performance of the chip. An active thermal management technique proposed here includes run time fully digital onchip temperature sensors, Dynamic Frequency Scaling (DFS) and active cooling topologies to enhance cooling effect of VLSI. The high resolution on chip temperature detector exhibit the temperature resolution of 0.0312°C, time resolution of 106 ps and measurement range from 0°C to 85°C with 21 sensing elements. The proposed thermal management techniques reduce the power dissipation by 30%. To enhance the thermal management capability further, there are numerous cooling methodologies developed and verified at 40 W of die power. With these topologies, the temperature of die at the power of 0 to 40 W lies between 0.5°C and 69°C. This is the worst case range amongst three cooling methodologies. The proposed work also nurtures the features of XILINX plan ahead tool's constrained effective area utilization, time constraints like TIMESPEC, TMRGRP, TPSync, TNM, Operating condition, hierarchybased synthesis and implementation for thermal management. The performance of Microblaze processors is boosted with effective area utilization, DFS and Thermo Electric Coolers (TEC). [ABSTRACT FROM AUTHOR]

In order to improve existing horse husbandry practices by providing social contact and exercise opportunities, it is necessary to fully understand the behaviour of horses in relation to group housing. Therefore, this study investigated the influence of dominance hierarchy on the locomotor behaviour and area utilization in a large group of horses in a pasture-based housing system in Northern Germany. The movements of 40 ponies with established group affiliations were observed over approximately one month from late August to early October 2022 using GPS technology. Their dominance hierarchy was determined by testing each possible combination in separate pair-feeding tests. For the determination of area utilization, the available space was divided into a total of 8889 quadrants with 3x3 m each. Analysis of daily distances travelled by the horses revealed an average of 5.4 ± 1.2 km/day, with no significant effect of social rank. However, age had a significant effect, with older horses walking shorter distances. Quadrants used per hour, as measure of area utilization, averaged 37.9 ± 6.4, with no effect of social rank but a significant effect of age observed. Heat maps showed full pasture utilization, with lower ranked horses having less access to resources around the watering trough and a greater use of less attractive grazing areas. The study suggests that in this specific setting, social rank did not significantly affect locomotor behaviour or area use. Although the study did not find a correlation between dominance rank and locomotor behaviour or area use, it highlighted the need for further research in different group sizes and housing systems to optimise group housing practices for horses, especially in settings with limited space and resources. • How dominance hierarchy affects daily distance and area utilization is studied. • Movement of a large herd of 40 horses is tracked over 1 month by GPS. • Rank had no influence on walked distances and area utilization. • Rank had an influence on visits to preferred resources. • Age and day influenced distances travelled and area utilization. [ABSTRACT FROM AUTHOR]

The aim of this study was to analyze the utilization of different stable areas of a total of 52 group-housed horses as well as their preferred stable parts and the use of resources. The study was situated in a “HIT Active Stable®” in Northern Germany for a period of 227 observation days. After dividing the whole farm area in a grid of 3 × 3 m, the dataset was examined with and without the pasture area. Furthermore, linear mixed models were applied. On average, horses used 53.2 ± 19 different squares per hour. The observation day (p < 0.001) and the covariate age (p < 0.001) had significant effects on the different squares visited per hour. No significant effects were found for sex (p = 0.30) and breed (p = 0.65) as only geldings and no stallions were part of the group and the distribution of the breeds was unfavorable. The random effect animal showed that the horse-individual estimates from −19.2 to 17.6 different squares visited per hour were quite large. Furthermore, it could be shown that the horses used resources such as feed stalls with a frequency of up to 0.14% more than other paddock areas without resources. Open lying halls with tarp skin were also preferred over the metal hall. The shelters were only partly popular. Use could be visualized with the help of heat maps. This study gives a good overview of the use of individual areas and resources and possible improvements.

1. Species potentially competing for the same resource are considered to be able to co-exist if they occupy different niches. In an apparent example of this, Adélie, Chinstrap and Gentoo penguins all feed predominantly on krill Euphausea superba at certain sites of sympatry in Antarctica and are proposed to exploit different niche hyper-volumes via differential area and depth utilization. 2. Patterns of foraging for 49 of these penguins breeding in sympatry were assessed using dead-reckoning loggers to examine foraging niche overlap. 3. Area use overlaps were 0·29 for Adélie ∩ Chinstrap, 0·44 for Adélie ∩ Gentoo, and 0·40 for Chinstrap ∩ Adélie and depth use overlaps were 0·69 for Adélie ∩ Chinstrap, 0·48 for Adélie ∩ Gentoo, and 0·52 for Chinstrap ∩ Gentoo Penguins. 4. Foraging efficiency was greatest for Adélie Penguins diving near surface waters (0–15 m) while Chinstraps were most efficient at medium depths (15–60 m) and Gentoo Penguins most efficient at deeper depths (> 60 m). There appear to be physiological reasons for this. Penguins primarily exploited those depths where they were most efficient. 5. The overlap for foraging periods was 0·47 for Adélie ∩ Chinstrap, 0·26 for Adélie ∩ Gentoo, and 0·40 for Chinstrap ∩ Gentoo Penguins. Chinstraps foraged primarily at night, Gentoos during the morning and Adélies in the afternoon. Temporal differences in foraging may result in the three species exploiting krill at those depths where it is best adapted to pursue it, this being mediated by the diel vertical migration of krill. 6. Integration of all measured parameters together gives minimal overlap between species with total overlaps of 0·09 for Adélie ∩ Chinstrap, 0·05 for Adélie ∩ Gentoo, and 0·08 for Chinstrap ∩ Gentoo Penguins so it appears that these penguins conform to conventional theory in avoiding competition in areas of sympatry. However, a model incorporating prey movement between hyper-volumes indicates that penguins may still compete, even in the virtual absence of hyper-volume overlap. 7. This study shows that Pygoscelid penguin do indeed exploit different hypervolumes in areas of sympatry but that such exploitation of different niches by sympatric species feeding on a common resource does not necessarily result in reduced competition if the mobility of prey is high. [ABSTRACT FROM AUTHOR]

The red king crab ( Paralithodes camtschaticus) was introduced in the Barents Sea in the 1960s and soon established a viable population. Proper management and exploitation of the Barents Sea king crab stock require better understanding of the spatial dynamics at different scales. This study examines the small-scale movement patterns of seven adult male crabs tracked for a period of up to one month from mid July to mid August at 150 m depth in a semi-enclosed fjord on the Russo-Norwegian border. The crabs were tagged with acoustic transmitters and their movements monitored with an acoustic positioning system. Low walking speeds (<0.01 m s−1) were most frequent but the crabs could move at a maximum speed of 0.15 m s−1 and walk an actual distance of up to 270 m over a period of one hour. However, the crabs usually moved within a relatively restricted area with mean hourly longest rectilinear distance varying from 26 to 64 m. The crabs alternated between periods of low and high activity, which could reflect feeding in and movements between food patches. The lack of a diel activity rhythm may be due to high light levels during the polar summer night, or a chemically mediated food search strategy. [ABSTRACT FROM AUTHOR]

Simple Summary: Horses are increasingly being kept in group stables where they are given the opportunity to move freely and to contact conspecifics. This study examined how the horses of a large group move in an active stable and which areas or resources they use over a period of 7.5 months with the help of linear mixed models. Therefore, a grid with the size of 3 × 3 m per square was applied. The horses used, on average, 53.2 ± 19 different squares per hour. It was shown that observation day (p < 0.001) and covariate age (p < 0.001) had significant effects on squares visited per hour. Sex (p = 0.30) and breed (p = 0.65) had no significant effects. A large variation in the squares visited per hour was determined for the individual horses. Most frequently visited were the individual resources, such as the feed stalls or lying halls. An open tarp skin lying hall was preferred over a metal hall. The shelters were only partly popular. An overview of the usage frequency of the paddock could be created by using heatmaps. Overall, specific conclusions about the use of individual areas and potential for improvement could be pointed out. The aim of this study was to analyze the utilization of different stable areas of a total of 52 group-housed horses as well as their preferred stable parts and the use of resources. The study was situated in a "HIT Active Stable®" in Northern Germany for a period of 227 observation days. After dividing the whole farm area in a grid of 3 × 3 m, the dataset was examined with and without the pasture area. Furthermore, linear mixed models were applied. On average, horses used 53.2 ± 19 different squares per hour. The observation day (p < 0.001) and the covariate age (p < 0.001) had significant effects on the different squares visited per hour. No significant effects were found for sex (p = 0.30) and breed (p = 0.65) as only geldings and no stallions were part of the group and the distribution of the breeds was unfavorable. The random effect animal showed that the horse-individual estimates from −19.2 to 17.6 different squares visited per hour were quite large. Furthermore, it could be shown that the horses used resources such as feed stalls with a frequency of up to 0.14% more than other paddock areas without resources. Open lying halls with tarp skin were also preferred over the metal hall. The shelters were only partly popular. Use could be visualized with the help of heat maps. This study gives a good overview of the use of individual areas and resources and possible improvements. [ABSTRACT FROM AUTHOR]