In this work, by replacing the traditional solid spokes with colloidal spokes, a vehicle wheel with a built-in suspension structure is proposed. Following the background and description of the wheel system, firstly, a vibration model of the wheel equipped with colloidal spokes is proposed, and based on such model the equivalent damping coefficients and spring constants are identified. Then, a m...

The Yoneda Lemma tells us that the Hom bifunctor is “non-degenerate” in a similar way. (a) For each object X ∈ C verify that hX := HomC(X,−) defines a functor C → Set. (b) Given two objects X,Y ∈ C state what it means to have hX ≈ hY as functors. (c) Given two objects X,Y ∈ C and an isomorphism of functors hX ≈ hY , prove that we have an isomorphism of objects X ≈ Y . [Hint: Let Φ : hX ∼ −→ hY ...

Elastic mechanisms are fundamental to fast and efficient movements. Mantis shrimp power their fast raptorial appendages using a conserved network of exoskeletal springs, linkages and latches. Their appendages are fantastically diverse, ranging from spears to hammers. We measured the spring mechanics of 12 mantis shrimp species from five different families exhibiting hammer-shaped, spear-shaped ...

wheat is a crop with spring and winter types and wide adaptability to different climate conditions. the wide adaptability of wheat is mainly controlled by three groups of genetic factors and among them vernalization (vrn) genes play pivotal role in determining spring and winter types. in this study, 395 iranian wheat landraces were characterized with specific primer pairs designed based on vrn-...

Bipedal robots are diicult to analyze mathematically. However, successful control strategies can be discovered using simple physical intuition and can be described in simple terms. Five things have to happen for a planar bipedal robot to walk. Height has to be stabilized. Pitch has to be stabilized. Speed has to be stabilized. The swing leg has to move so that the feet are in locations which al...

This article describes a mechanical vertical attenuation system capable to provide large attenuation factors above 1Hz. This system is derived from, and improves, the passive Geometric Anti-Spring seismic attenuation filters minimizing their vertical resonant frequency by means of a tunable electromagnetic spring mounted in parallel with the main spring. The tunable spring is also used to compe...

Dissolved concentrations of four forms of arsenic: arsenite, arsenate, monomethylarsenic, and dimethylarsenic, were measured in the Patuxent River Estuary near Benedict, Maryland, over two annual cycles. In each year, total arsenic concentrations peaked in the summer, in lateJuly and August, while minimum concentrations occurred in winter. Except in late winter, arsenate was a predominant form ...