With some exceptions, an Employee is covered by the HCSO if the Employee works for an Employer covered by the HCSO and: 1  Is entitled to be paid the minimum wage; 2  Has been employed by the Employer for at least 90 calendar days; and. 3  Works at least 8 hours per week in San Francisco.
Vortex ring. Spark photography image of a vortex ring in flight. A vortex ring, also called a toroidal vortex, is a torus-shaped vortex in a fluid or gas; that is, a region where the fluid mostly spins around an imaginary axis line that forms a closed loop. The dominant flow in a vortex ring is said to be toroidal, more precisely poloidal.
A torus is a surface formed by revolving a circle about a line. Often, tori (the plural of torus) are doughnut shaped, as in the main image here. It is formed by revolving a circle about the z-axis. It can also be described as a ring-shaped surface with a hole. torus with one hole is simply referred to as the torus. A torus with two holes is called the 2-torus or the double torus, one with three holes is the 3-torus or triple torus. A torus with holes is the-torus. Mathematically, we can describe tori using several different equations.