Inviscid computations are presented of a self-propelled virtual body connected to combined heaving and pitching foil that uses continuous intermittent motions. It is determined swimming can improve efficiency when the dimensionless heave ratio $h^* < 0.7$ while it degrades for \geq 0.7$. This consequence physical origins force production pitch-dominated ($h^* 0.5$) heave-dominated > Based on in...

Expansive soils shrink and swell with drying wetting cycles. The shrink-swell capacity of expansive can result in differential movement beneath foundations which is a very common cause foundation problems. Ribbed slab, often called waffle one the efficient inexpensive solutions for use under light structures resting on soils. This paper presents numerical analysis that used to calculate displac...

In order to study the influencing factors of floor deformation and heave mechanisms deep mining roadways, this paper takes dynamic pressure roadway a mine as engineering background adopts research method combining theoretical analyses, numerical simulations field observations influence various on mechanisms. It is determined that are large buried depth, long duration pressure, unique characteri...

[1] We studied soil properties of frost boils at nine zonal-vegetation locations across the North American Arctic Transect (NAAT) in order to better understand arctic soils and their interaction with other biogeophysical components of frost boil ecosystems. Soil genetic horizons were analyzed for particle size, pH, electrical conductivity, total organic carbon (OC) and nitrogen (N), bulk densit...

Weakly electric fish are extraordinarily maneuverable swimmers, able to swim as easily forward as backward and rapidly switch swim direction, among other maneuvers. The primary propulsor of gymnotid electric fish is an elongated ribbon-like anal fin. To understand the mechanical basis of their maneuverability, we examine the hydrodynamics of a non-translating ribbon fin in stationary water usin...

Tuna are fast, economical swimmers in part due to their stiff, high aspect ratio caudal fins and streamlined bodies. Previous studies using passive caudal fin models have suggested that while high aspect ratio tail shapes such as a tuna's generally perform well, tail performance cannot be determined from shape alone. In this study, we analyzed the swimming performance of tuna-tail-shaped hydrof...

An undulatory pattern of body bending in which waves pass along the body from head to tail is a major mechanism of creating thrust in many fish species during steady locomotion. Analyses of live fish swimming have provided the foundation of our current understanding of undulatory locomotion, but our inability to experimentally manipulate key variables such as body length, flexural stiffness and...

We study free-floating point absorption wave generators, consisting of an assemblage of one or a few (mostly heaving) spar buoys, housing at least one short-stroke linear generator (SSLG), made of a magnet, suspended to a spring, and oscillating within a coil. This system is aimed at producing low and renewable wave power (up to kW) for marine coastal surveillance systems. Both scale model expe...

Abstract As one of the most common disasters in deep mine roadway, floor heave has caused serious obstacles to transportation and normal production activities. The third section winch roadway mining area Qitaihe Longhu coal a due large buried depths semicoal rock maximum is 750 mm. For problem stability, this paper establishes mechanical model analyze stability by analogy with basement foundati...