Previous studies have shown that the formation of coherent vortex rings in the nearwake of a self-propelled vehicle can increase propulsive efficiency compared with a steady jet wake. The present study utilizes a self-propelled vehicle to explore the dependence of propulsive efficiency on the vortex ring characteristics. The maximum propulsive efficiency was observed to occur when vortex rings ...

One of the disadvantages of conventional milling tools is to produce a large amount of heat in cutting zone and so making the tool warmer. As a result, the tool would be worn and its life time would be reduced. Therefore, in long time machining, it is essential to change inserts and tools, continiously. A milling tool with self rotary cutting inserts was designed and manufactured that enables i...

Self-propelled rods, which propel by themselves in the direction from the tail to the head and align nematically through collision, have been well-investigated theoretically. Various phenomena including true long-range ordered phase with the Giant number fluctuations, and the collective motion composed of many vorices were predicted using the minimal mathematical models of self-propelled rods. ...

Light-activated self-propelled colloids are synthesized and their active motion is studied using optical microscopy. We propose a versatile route using different photoactive materials, and demonstrate a multiwavelength activation and propulsion. Thanks to the photoelectrochemical properties of two semiconductor materials (α-Fe2O3 and TiO2), a light with an energy higher than the bandgap trigger...

We propose a computable Galois-connection between, on the one hand, Cattell’s 16-Personality-Factor (16PF) Profiles, one of the most comprehensive and widely-used personality measures for non-psychiatric populations and their containing PsychEval Personality Profiles (PPPs) for psychiatric populations, and, on the other hand, Szondi’s personality profiles (SPPs), a less well-known but, as we sh...

A fuel-free autonomous self-propelled motor is illustrated. The motor is powered by the chemistry of calcium carbide and utilising water as a co-reactant, through a polymer encapsulation strategy. Expulsion of acetylene bubbles powers the capsule motor. This is an important step, going beyond the toxic hydrogen peroxide fuel used normally, to find alternative propellants for self-propelled mach...

We propose a computable Galois-connection between Myers-Briggs’ Type Indicators (MBTIs), the most widely-used personality measure for non-psychiatric populations (based on C.G. Jung’s personality types), and Szondi’s personality profiles (SPPs), a less well-known but, as we show, finer personality measure for psychiatric as well as non-psychiatric populations (conceived as a unification of the ...

The single-period problem (SPP), also known as the newsboy or news-vendor problem, is to ®nd the order quantity which maximizes the expected pro®t in a single period probabilistic demand framework. Interest in the SPP remains unabated and many extensions to it have been proposed in the last decade. These extensions include dealing with di€erent objectives and utility functions, di€erent supplie...