Quirino Sugon Jr, PhD

Volume of a Cylinder  The volume \(V\) of a cylinder with radius \(r\), height \(h\) is given by \[V = \pi r^2 h.\] Notice that we have three parameters. If we hold one of them to be constant, then we can obtain the relationship between the other two parameters, especially if one of these two parameters is uniformly or linearly increasing, i.e., a linear function of a set of integers \(k =\{0, 1, 2, \ldots, n\}\), where \(n\) is an arbitrary integer ideally greater than or equal to 3.  Let us consider three cases: constant volume, constant radius, and constant height. Each of these cases will have two sub-cases, with each sub-case dictating the design of a row of Montessori knobbed cylinders. Thus, in principle, you can design a total of 6 rows of knobbed cylinders, with each row containing \(n\) cylinders. 1. Constant volume \(V\) If the volume \(V=V_0\) is constant, then the radius \(r\) of the cylinder is inversely proportional to the square root of the height \(h\): \[r =\...

Vincent S. Cronin wrote A Primer on Focal Mechanism Solutions for Geologists (2010) . My interest in his work is in his descriptions of fault vectors and angles. I need to use these standard names if I wish to write a paper on Focal Mechanism of Earthquakes. Based on Cronin's diagram in p. 6, the reference strike, which we shall denote by $\mathbf e_{strike}$ appears to be the direction of the fault line as seen from a drone camera flying overhead high above the fault. The dip vector, which we shall denote by $\mathbf e_{dip}$, is a vector perpendicular to the reference strike $\mathbf e_{strike}$ and lies along the fault plane. The direction of $\mathbf e_{dip}$ is downward along the fault in Cronin. In this way, if we define the rake $\mathbf e_{rake}$ as the direction of the movement of the one side of the fault, then $\mathbf e_{rake}$ can be expressed as a rotation of $\mathbf e_{strike}$ about $\mathbf e_{dip}\times\mathbf e_{strike}$ by an angle $\theta_{rake}$, which is...