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This research explores how the dynamic behaviour under cyclic compression loading affects compaction characteristics. Three types of sand, varying in fines content, are compacted under different saturation (${{\rm{S}}_{\rm{r}}}$ S r ) and compaction (${{\rm{D}}_{\rm{c}}}$ D c ) levels. Suction-controlled drained cyclic loading tests are conducted to predict axial strain accumulation, with initial suction measured for each compacted state. The study seeks to understand the correlation between axial strain accumulation and initial suction across soil types. Findings indicate that initial soil suction, influenced by saturation, significantly impacts axial strain under cyclic loading. Lower saturation enhances particle bonding, increasing initial suction and reducing strain accumulation. Moreover, an increase in fines content results in greater strain accumulation. Despite that, sands with elevated fines (18.8%) can achieve similar soil performance through effective compaction with precise saturation control. This underscores the role of saturation in moisture regulation during compaction, particularly for sands with higher non-plastic fines content, in achieving effective compaction. [ABSTRACT FROM AUTHOR]

Electrification of power takeoff systems, which aims to cut down the fuel consumption of heavy-duty vehicles, needs a high voltage gain dc/dc converter with wide load and input voltage range soft-switching for high efficiency and high transformer utilization factor. Bulky input filter and transformer as well as complex frequency modulation limit voltage source resonant converters to suit such applications. The proposed current-fed series resonant converter eliminates these drawbacks. The resonant tank maintains tank currents, thus conduction losses, in proportion to the load demand to offer flat efficiency curve. On the other hand, the parallel resonant inductor can be designed to maintain wide load and input voltage range soft-switching. Also, simple pulsewidth modulation of the proposed converter at constant switching frequency complements its merits. This article presents the operation, analysis, modeling, and design of the proposed converter. Hardware setup has been mounted and tested to verify the proposed theory. [ABSTRACT FROM AUTHOR]

Introduction: Knowledge on shaping ability of advanced Nickel Titanium (NiTi) rotary instruments holds a great significance in the field of endodontics. Root canal shaping systems should maintain the original canal anatomy and thereby, reduce the risk of iatrogenic errors. Aim: To compare and evaluate the canal transportation, centering ability and time taken for preparation of curved root canals after instrumentation with F6 SkyTaper, Navigator EVO and One Shape file systems using Cone Beam Computed Tomography (CBCT) imaging. Materials and Methods: This was an in-vitro study conducted in the Department of Conservative Dentistry and Endodontics, I.T.S Centre for Dental Studies and Research, Ghaziabad, Uttar Pradesh, India in July 2020. Thirty mesiobuccal canals of extracted mandibular molars with an angle of curvature between 20 to 40 degrees were selected and divided into three groups (n=10 into each group): F6 SkyTaper (group I), Navigator Evo (group II) and One Shape (group III). Canals were biomechanically prepared till size 30/6%; scanned using CBCT, before and after instrumentation to evaluate shaping ability at 3 mm, 5 mm, 7 mm and 9 mm from the apex. The results were subjected to statistical analysis using Analysis of variance (ANOVA) and Bonferroni post-hoc test with level of significance set at p-value<0.05. Results: Out of three file systems selected, Navigator EVO showed significantly least canal transportation (0.222) (p-value<0.05)and highest centering ability (0.535) as compared to F6 SkyTaper and One Shape. Overall, F6 SkyTaper and One Shape showed comparable results with respect to canal transportation and centering ability. F6 skyTaper showed the fastest preparation (75.72 sec) of canals while Navigator EVO took the maximum time (307.046 sec). Conclusion: Navigator EVO showed superior shaping ability in curved canals than single file systems, although the time taken was the least with F6 SkyTaper. [ABSTRACT FROM AUTHOR]