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User:Eml4500.f08.Ateam.paquette/Homework1

MATLAB Tutorial: Part 2

Managing M-files

The !-feature allows for editing or printing to be done without having to exit MATLAB. Using the command !ed will let the named file be edited and then returned to MATLAB where you left off. Many commands control the working directory. Pwd returns the name of the present working directory. Cd changes the working directory. Dir or ls lists the contents of the working directory, but what lists only the M-files. Files named matlab are accessible from any directory. M-files have to be in a directory MATLAB can excess.

Comparing efficiency of an algorithms: flops, tic and toc

The efficiency of an algorithm can be measured by the number of floating point operations (flops) performed and the elapsed time. The total number of flops performed is kept track of by the function flops. This number can be reset by the command flops(0). Tic and toc are stopwatch times that can return the elapsed time. Tic starts the timer and toc returns the elapsed time.

Output format

The output on display is controlled by a variety of format commands, but the computations are done in double precision. Format compact suppresses most of the blank lines so more information can be added on the screen, while format loose returns the display back.

Hardcopy

The diary command causes the next code written to be written on the name diskfile until the command diary off is given. After this is done the file can be edited and printed on the local system.

Graphics

MATLAB can create planar plots of curves, 3-D plots of curves, 3-D mesh surface plots, and 3-D faceted surface plots.

Planar plots

The command plot produces a liner x-y plot. Plot(x,y) will draw an x-y plot if the vectors x and y are the same length. There can be many different graphic figures, but only one at a time will be call “current.” The command figure(1) will make figure 1 the current figure if it was not before, and gcf will return the number of which figure is current. An example of a linear x-y plot is shown below.

 * x = -1.5:.01:1.5; y = exp(-x.^2); plot(x,y)

Fplot is used to plot the graph of a function. Plots can be made of parametrically defined curves as well.

 * t=0:.001:2*pi; x=cos(3*t); y=sin(2*t); plotx,y)

All graphs can be given titles, labeled axes, and text within the graph.

 * Title: graph title

 * xlabel: x-axis label

 * ylabel: y-axis label

 * gtext: place text on graph using mouse

 * text: place text at specified coordinates

Axes are auto-scaled, but this can be overwritten with the command axis. This command should always be given after the plot command. Multiple plots can also be displayed on a single graph.

 * x = 0: .01:2*pi; y1 = sin(x); y2 = sin(2*x); y3 = sin(4*x); plot(x,y1,x,y2,x,y3)

This can also be done with the hold command. It freezes the current on screen graphics so other plots can be put on the same graph, but the axes may become rescaled. Colors and line types can be added to a plot as well. The code plot(x,y,’r--‘) shows a red dashed line.

Graphics hardcopy

The command print is the easiest way to send a high-resolution copy of the current graphics figure to the default printer. The printopt M-file identifies the default setting used by the print command. Print filename saves the figure to the filename given in the default format. If there is no extension in the filename then the default file format will be assigned. A file will be overwritten if the filename already exists. The option –append will append the current graphics figure into the existing file so more than one figure can be saved in each file. The command code is print –append filename. This command can be overwritten with the option –f3.

3-D line plots

Plot3 makes a curve in three dimensions. If x, y, and z are defined vectors of the same size, then plot3(x,y,z) will create a 3-D curve passing through the coordinates of the respective elements. A zlabel can still be added to this plot. The helix shown below was created using the code:

 * t = .01: .01:20*pi; x = cos(t); y = sin(t); z = t.^3; plot3(x,y,z)

3-D mesh and surface plots

A three dimensional wire mesh surface plot with the elements of matrix z is created with the command mesh(z). The function meshgrid allows for a graph to be drawn over a rectangle by allowing matrices to be created. Surface plots are created using surf(z).

z=e-x^2-y^2 can be drawn over the square [-2,2]x[-2,2] with the following codes:
 * xx = -2: .2:2;

 * yy = xx;

 * [x,y] = meshgrid(xx,yy);

 * z = exp(-x.^2 – y.^2);

 * mesh(z)

Surf(z) of the same code is shown as well.

There are three different settings for the color shading of surfaces: faceted, interpolated, and flat. The command shading should be done after the surf command. Different color profiles can be produced by the command colormap.

Handle Graphics.

MATLAB contains many different graphic functions. The user is able to control almost all of the graphics allowing for detailed plots to be made.

Sparse Matrix Computations

MATLAB provides the ability to save storage space, so larger problems can be solved, by only storing the nonzero elements of the matrix. Matlab has the storage mode full, the default, and sparse. The sparse matrix is stored as a linear array of its nonzero elements. The output of a matrix in sparse mode is a list of nonzero entries and their row and column indices. A matrix is sparse if any constituent block is sparse.


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User:Eml4500.f08.Ateam.paquette/Homework2

 Global Force Displacement Relation

The Global Force Displacement Relation is known as K d = F. Matrix K is the element stiffness matrix in global coordinates. In our example, the global stiffness matrix is a 6 x 6 grid, the global displacement matrix is 6 x 1, and the global force matrix is 6 x 1, and is shown below:

 * $$\begin{Bmatrix} F_1 \\ F_2 \\ F_3 \\ F_4 \\ F_5 \\ F_6 \end{Bmatrix} = \begin{bmatrix}

K_{11}&K_{12}&K_{13}&K_{14}&K_{15}&K_{16} \\ K_{21}&K_{22}&K_{23}&K_{24}&K_{25}&K_{26} \\ K_{31}&K_{32}&K_{33}&K_{34}&K_{35}&K_{36} \\ K_{41}&K_{42}&K_{43}&K_{44}&K_{45}&K_{46} \\ K_{51}&K_{52}&K_{53}&K_{54}&K_{55}&K_{56} \\ K_{61}&K_{62}&K_{63}&K_{64}&K_{65}&K_{66} \\ \end{bmatrix} \begin{Bmatrix} d_1 \\ d_2 \\ d_3 \\ d_4 \\ d_5 \\ d_6 \end{Bmatrix}$$

Since the stiffness matrix is 6 x 6, there are six degrees of freedom in the problem. The Global Force Displacement Relation can be shown in a more compact notation:
 * $$\begin{bmatrix} K_{ij} \end{bmatrix} \begin{Bmatrix} d_{j} \end{Bmatrix} = \begin{Bmatrix} F_{i} \end{Bmatrix}$$

or    $$\sum_{j=1}^6 $$ Kij dj  = Fi , i=1,2,3,4,5,6

K or $$\begin{bmatrix} K_{ij} \end{bmatrix}$$n x n is the global stiffness matrix. d or $$\begin{Bmatrix} d_{j} \end{Bmatrix}$$n x 1 is the global displacement matrix. F or $$\begin{Bmatrix} F_{i} \end{Bmatrix}$$n x 1 is the global force matrix.

These global matrices are different than the element force displacement relation k(e) d(e) = f(e). In this relationship, recall the k(e) is a 4 x 4 matrix, called the element stiffness matrix where (e) is the element number. d(e) and f(e) are the element displacement and force matrices, both of which are 4 x 1. These element matrices are smaller than the global ones because each one pertains to an element rather than the entire picture. To go from an element matrix to a global matrix, the correspondence between the element displacement degrees of freedom and the global displacement degrees of freedom need to be identified.

At the global level, the degrees of freedom are $$d_1,\ d_2,\ d_3,\ d_4,\ d_5,\ d_6$$. At the element level, there is a set of degrees of for each element.

In Element 1, the degrees of freedom are $$d_1^{(1)},\ d_2^{(1)},\ d_3^{(1)},\ d_4^{(1)}$$. Element 2 is $$d_1^{(2)},\ d_2^{(2)},\ d_3^{(2)},\ d_4^{(2)}$$.

The schematic above shows that some of the global degrees of freedom are the same as the element. At node 1:
 * d1 = d1(1)
 * d2 = d2(1)

Node 2 on the global schematic has the same displacement degrees of freedom as on both the first and second element; therefore:
 * d3 = d3(1) = d1(2)

 * d4 = d4(1) = d2(2)

Node 3 is only:
 * d5 = d3(2)
 * d6 = d4(2)

The conceptual step of assembly has a small matrix for each element stiffness matrix and two zero matrices all within the global force displacement relation. The basic matrix is shown below:

$$\begin{Bmatrix} d_1 \\ d_2 \\ d_3 \\ d_4 \\ d_5 \\ d_6 \end{Bmatrix} = \begin{Bmatrix} F_1 \\ F_2 \\ F_3 \\ F_4 \\ F_5 \\ F_6 \end{Bmatrix}$$

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


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User:EML4500.f08.Ateam.Miller/homework2

Step 4: Elimination of Known Degrees of Freedom by Reducing the Global Force-Displacement Relationship
The next step in the Finite Element Method is to eliminate the known degrees of freedom by reducing the global force-displacement relationship. The displacement matrix from the previous two-truss system can be reduced by applying the fixed boundary conditions:

$$d_1=d_2=d_5=d_6=0$$

The resulting displacement matrix is:

$$d= \begin{bmatrix} 0 \\ 0 \\ d_3  \\ d_4 \\ 0 \\ 0 \end{bmatrix} $$

After applying these conditions, the corresponding columns in the global stiffness matrix can be deleted and the resulting matrix is shown below.

$$F=K \begin{bmatrix} 0 \\ 0 \\ d_3  \\ d_4 \\ 0 \\ 0 \end{bmatrix} = \begin{bmatrix} k_{13} & k_{14} \\ k_{23} & k_{24} \\ k_{33} & k_{34} \\ k_{43} & k_{44} \\ k_{53} & k_{54} \\ k_{63} & k_{64} \\ \end{bmatrix} \begin{bmatrix} d_3 \\ d_4 \\ \end{bmatrix} $$

The next step in reducing the force-displacement relationship is to apply the Principle of Virtual Work. This allows the corresponding rows of the global stiffness matrix and the global force matrix to be deleted. The resulting force-displacement relation is

$$ \begin{bmatrix} k_{33} & k_{34} \\ k_{43} & k_{44} \\ \end{bmatrix} \begin{bmatrix} d_3 \\ d_4 \\ \end{bmatrix}= \begin{bmatrix} F_3 \\ F_4 \\ \end{bmatrix} $$ or $$\mathbf{K}\cdot\mathbf{d} = \mathbf{F}$$

Based on the given information, the reduced force matrix is a known, as shown below.

$$\underline{\overline{F}}= \begin{bmatrix} F_3 \\ F_4 \\ \end{bmatrix}= \begin{bmatrix} 0 \\ P \\ \end{bmatrix}= \begin{bmatrix} 0 \\ 7 \\ \end{bmatrix} $$

Finally, the reduced global displacement matrix can be solved by multiplying the reduced force matrix by the inverse of the reduced global stiffness matrix.

$$ \begin{bmatrix} d_3 \\ d_4 \\ \end{bmatrix} =\begin{bmatrix} k_{33} & k_{34} \\ k_{43} & k_{44} \\ \end{bmatrix}^{-1} \begin{bmatrix} 0 \\ P \\ \end{bmatrix}= \begin{bmatrix} 4.352 \\ 6.127 \\ \end{bmatrix} $$

Step 5: Compute Reactions
After the displacements of Node 2 are computed, then the next step is to compute the reactions. There are two methods that can be used to compute the reactions. The first method is to use the element force-displacement relations

$$k^{(e)}d^{(e)}=f^{(e)}$$

for elements 1 and 2. The element displacement matrices can be determined from the global displacement matrix.

$$\underline{d}^{(1)}= \begin{bmatrix} 0 \\ 0 \\ 4.352 \\ 6.127 \\ \end{bmatrix}

\underline{d}^{(2)}= \begin{bmatrix} 4.352 \\ 6.127 \\ 0 \\ 0 \\ \end{bmatrix} $$

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User:Eml4500.f08.ramrod.D/DO HW2

 WARNING: Please move your work to the user namespace, and request a deletion of all of your wiki page under the main namespace by inserting the delete or delete my page template at the top of the page so wikiversity custodian could delete them. Remember to log in when you perform these operations so you are not mistaken to be vandals. Failure to do the above immediately will result in a lower HW grade. Eml4500.f08 09:28, 25 September 2008 (UTC)

Lecture Notes 9/15/2008
$$\mathbf{K}= \begin{bmatrix} k_{11}^{(1)} & k_{12}^{(1)} & k_{13}^{(1)} & k_{14}^{(1)} & 0 & 0\\k_{21}^{(1)} & k_{22}^{(1)} & k_{23}^{(1)} & k_{24}^{(1)} & 0 & 0\\k_{31}^{(1)} & k_{32}^{(1)} & (k_{33}^{(1)}+k_{11}^{(2)}) & (k_{34}^{(1)}+k_{12}^{(2)}) & k_{13}^{(2)} & k_{14}^{(2)}\\k_{41}^{(1)} & k_{42}^{(1)} & (k_{43}^{(1)}+k_{21}^{(2)}) & (k_{44}^{(1)}+k_{22}^{(2)}) & k_{23}^{(2)} & k_{24}^{(2)}\\0 & 0 & k_{31}^{(2)} & k_{32}^{(2)} & k_{33}^{(2)} & k_{34}^{(2)}\\0 & 0 & k_{41}^{(2)} & k_{42}^{(2)} & k_{43}^{(2)} & k_{44}^{(2)}\end{bmatrix}$$

The appropriate numbers will be inputted into matrix K which is a 6x6 matrix.

$$\mathbf{K}= \begin{bmatrix} K_{11} & K_{12} & K_{13} & K_{14} & K_{15} & K_{16}\\K_{21} & K_{22} & K_{23} & K_{24} & K_{25} & K_{26}\\K_{31} & K_{32} & K_{33} & K_{34} & K_{35} & K_{36}\\K_{41} & K_{42} & K_{43} & K_{44} & K_{45} & K_{46}\\K_{51} & K_{52} & K_{53} & K_{54} & K_{55} & K_{56}\\K_{61} & K_{62} & K_{63} & K_{64} & K_{65} & K_{66}\end{bmatrix}$$

$$\mathbf{}= \begin{bmatrix} 0.5625 & 0.32475 & -0.5625 & -0.32475 & 0 & 0\\0.32475 & 0.1875 & -0.3247 & -0.1875 & 0 & 0\\-0.5625 & -0.32475 & (0.5625+2.5) & (0.32475-2.5) & -2.5 & 2.5\\-0.32475 & -0.1875 & (0.32475-2.5) & (0.1875+2.5) & 2.5 & -2.5\\0 & 0 & -2.5 & 2.5 & 2.5 & -2.5\\0 & 0 & 2.5 & -2.5 & -2.5 & 2.5\end{bmatrix}$$

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User:Scytheh

Estudande de Ciências Contábeis.

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User:Eml4500.f08.ramrod.D/HW2

Lecture Notes 9/15/2008
$$\mathbf{K}= \begin{bmatrix} K_{11} & K_{12} & K_{13} & K_{14} & K_{15} & K_{16}\\K_{21} & K_{22} & K_{23} & K_{24} & K_{25} & K_{26}\\K_{31} & K_{32} & K_{33} & K_{34} & K_{35} & K_{36}\\K_{41} & K_{42} & K_{43} & K_{44} & K_{45} & K_{46}\\K_{51} & K_{52} & K_{53} & K_{54} & K_{55} & K_{56}\\K_{61} & K_{62} & K_{63} & K_{64} & K_{65} & K_{66}\end{bmatrix}$$

The appropriate numbers will be inputted into matrix K which is a 6x6 matrix.

$$\mathbf{K}= \begin{bmatrix} k_{11}^{(1)} & k_{12}^{(1)} & k_{13}^{(1)} & k_{14}^{(1)} & 0 & 0\\k_{21}^{(1)} & k_{22}^{(1)} & k_{23}^{(1)} & k_{24}^{(1)} & 0 & 0\\k_{31}^{(1)} & k_{32}^{(1)} & (k_{33}^{(1)}+k_{11}^{(2)}) & (k_{34}^{(1)}+k_{12}^{(2)}) & k_{13}^{(2)} & k_{14}^{(2)}\\k_{41}^{(1)} & k_{42}^{(1)} & (k_{43}^{(1)}+k_{21}^{(2)}) & (k_{44}^{(1)}+k_{22}^{(2)}) & k_{23}^{(2)} & k_{24}^{(2)}\\0 & 0 & k_{31}^{(2)} & k_{32}^{(2)} & k_{33}^{(2)} & k_{34}^{(2)}\\0 & 0 & k_{41}^{(2)} & k_{42}^{(2)} & k_{43}^{(2)} & k_{44}^{(2)}\end{bmatrix}$$

$$k_{11}^{(1)}=\frac{9}{16}=0.5625$$

$$k_{12}^{(1)}=\frac{3\sqrt{3}}{16}=0.3248$$

$$k_{13}^{(1)}=-k_{11}^{(1)}=-0.5625$$

$$k_{14}^{(1)}=-k_{12}^{(1)}=-0.3248$$

$$k_{22}^{(1)}=\frac{3}{16}=0.1875$$

$$k_{24}^{(1)}=-k_{22}^{(1)}=-0.1875$$

$$k_{13}^{(2)}=-k_{11}^{(2)}=\frac{-5}{2}=-2.5$$

$$k_{14}^{(2)}=-k_{12}^{2}=2.5$$

$$k_{24}^{(2)}=\frac{-5}{2}=-2.5$$

$$k_{33}^{(2)}=\frac{5}{2}=2.5$$

$$k_{34}^{(2)}=\frac{-5}{2}=-2.5$$

$$k_{44}^{(2)}=\frac{5}{2}=2.5$$

$$K_{15}^{}=K_{16}=K_{25}=K_{26}=K_{51}=K_{52}=K_{61}=K_{62}=0$$

$$\mathbf{}= \begin{bmatrix} 0.5625 & 0.32475 & -0.5625 & -0.32475 & 0 & 0\\0.32475 & 0.1875 & -0.3247 & -0.1875 & 0 & 0\\-0.5625 & -0.32475 & (0.5625+2.5) & (0.32475-2.5) & -2.5 & 2.5\\-0.32475 & -0.1875 & (0.32475-2.5) & (0.1875+2.5) & 2.5 & -2.5\\0 & 0 & -2.5 & 2.5 & 2.5 & -2.5\\0 & 0 & 2.5 & -2.5 & -2.5 & 2.5\end{bmatrix}$$

$$\mathbf{K}=\begin{bmatrix} 0.5625 & 0.3248 & -0.5625 & -0.3248 & 0 & 0\\0.3248 & 0.1875 & -0.3248 & -0.1875 & 0 & 0\\-0.5625 & -0.3248 & 3.0625 & -2.1752 & -2.5 & 2.5\\-0.3248 & -0.1875 & -2.1752 & 2.6875 & 2.5 & -2.5\\0 & 0 & -2.5 & 2.5 & 2.5 & -2.5\\0 & 0 & 2.5 & -2.5 & -2.5 & 2.5\end{bmatrix}$$

Two Bar Truss System MATLAB Code
This section goes over the finite element MATLAB code for a two bar truss system. All of the resulting matrices are below the code. The MATLAB example code can also be found on Dr. Vu-Quoc's website:

http://clesm.mae.ufl.edu/~vql/courses/fead/2008.fall/codes/twoBarTrussEx.txt

% Two bar truss example clear all; e = [3 5]; A = [1 2]; P = 7; L=[4 2]; alpha = pi/3; beta = pi/4;

nodes = [0, 0; L(1)*cos(pi/2-alpha), L(1)*sin(pi/2-alpha); L(1)*cos(pi/2-alpha)+L(2)*sin(beta),L(1)*sin(pi/2-alpha)-L(2)*cos(beta)];

dof=2*length(nodes);

conn=[1,2; 2,3]; lmm = [1, 2, 3, 4; 3, 4, 5, 6]; elems=size(lmm,1); K=zeros(dof); R = zeros(dof,1); debc = [1, 2, 5, 6]; ebcVals = zeros(length(debc),1);

%load vector R = zeros(dof,1); R(4) = P;

% Assemble global stiffness matrix K=zeros(dof); for i=1:elems lm=lmm(i,:); con=conn(i,:); k_local=e(i)*A(i)/L(i)*[1 -1; -1 1] k=PlaneTrussElement(e(i), A(i), nodes(con,:)) K(lm, lm) = K(lm, lm) + k; end K R % Nodal solution and reactions [d, reactions] = NodalSoln(K, R, debc, ebcVals) results=[]; for i=1:elems results = [results; PlaneTrussResults(e, A, ...           nodes(conn(i,:),:), d(lmm(i,:)))]; end format short g results

k_local = 0.75       -0.75        -0.75         0.75

k = 0.5625     0.32476      -0.5625     -0.32476      0.32476       0.1875     -0.32476      -0.1875      -0.5625     -0.32476       0.5625      0.32476     -0.32476      -0.1875      0.32476       0.1875

k_local = 5   -5    -5     5

k = 2.5        -2.5         -2.5          2.5         -2.5          2.5          2.5         -2.5         -2.5          2.5          2.5         -2.5          2.5         -2.5         -2.5          2.5

K = 0.5625     0.32476      -0.5625     -0.32476            0            0      0.32476       0.1875     -0.32476      -0.1875            0            0      -0.5625     -0.32476       3.0625      -2.1752         -2.5          2.5     -0.32476      -0.1875      -2.1752       2.6875          2.5         -2.5            0            0         -2.5          2.5          2.5         -2.5            0            0          2.5         -2.5         -2.5          2.5

R = 0    0     0     7     0     0

d =

0           0        4.352       6.1271            0            0

reactions = -4.4378     -2.5622       4.4378      -4.4378

results = 1.7081      5.1244       8.5406       5.1244       17.081       0.6276       1.8828        3.138       1.8828        6.276

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User:Eml4500.f08.team.guan/hw2v2

9.1-9.2

Global Stiffness Matrix
Going from the elemental stiffness matrices to the global stiffness matrix, the correspondence between displacement degrees of freedom, globally and locally, must be identified. Due to the sharing of nodes of different elements, some local displacement degrees of freedom will equal each other because the deflection of the local nodes are constrained by the fact that these local nodes share a same global node. Upon, identifying these similarities and relationships, the assembly of the global stiffness matrix can be written in terms of elemental stiffness values. This is the topology of $$\displaystyle K$$. First, it is necessary to just recall the element stiffness matrices. $$\displaystyle k^{(1)}_{matrix} $$ = $$\begin{bmatrix} k_{11}^{(1)} & k_{12}^{(1)} &k_{13}^{(1)} &k_{14}^{(1)} \\ k_{21}^{(1)} & k_{22}^{(1)} &k_{23}^{(1)} &k_{24}^{(1)} \\ k_{31}^{(1)} & k_{32}^{(1)} &k_{33}^{(1)} &k_{34}^{(1)} \\ k_{41}^{(1)} & k_{42}^{(1)} &k_{43}^{(1)} &k_{44}^{(1)} \\ \end{bmatrix} $$  , $$\displaystyle k^{(2)}_{matrix} $$ = $$\begin{bmatrix} k_{11}^{(2)} & k_{12}^{(2)} &k_{13}^{(2)} &k_{14}^{(2)} \\ k_{21}^{(2)} & k_{22}^{(2)} &k_{23}^{(2)} &k_{24}^{(2)} \\ k_{31}^{(2)} & k_{32}^{(2)} &k_{33}^{(2)} &k_{34}^{(2)} \\ k_{41}^{(2)} & k_{42}^{(2)} &k_{43}^{(2)} &k_{44}^{(2)} \\

\end{bmatrix} $$ Also, it is necessary to recall the relationships between the local displacement degrees of freedom and the global displacement degrees of freedom: $$\displaystyle d_1^{(1)}=d_1, d_2^{(1)}=d_2, d_3^{(1)}=d_3=d_1^{(2)}, d_4^{(1)}=d_4=d_2^{(2)}, d_5^{(2)}=d_5, d_4^{(2)}=d_6$$ $$\displaystyle d_{global} $$ = $$\begin{bmatrix} d_{1} \\ d_{2} \\ d_{3} \\ d_{4} \\ d_5 \\ d_6\\ \end{bmatrix}$$  , $$\displaystyle d^{(1)} $$ = $$\begin{bmatrix} d_{1}^{(1)} \\ d_{2}^{(1)} \\ d_{3}^{(1)} \\ d_{4}^{(1)} \\ \end{bmatrix}$$  , $$\displaystyle d^{(2)} $$ = $$\begin{bmatrix} d_{1}^{(2)} \\ d_{2}^{(2)} \\ d_{3}^{(2)} \\ d_{4}^{(2)} \\ \end{bmatrix}$$

 Now, it is possible to construct the global stiffness matrix: $$\displaystyle K_{global} $$ = $$\begin{bmatrix} k_{11}^{(1)} & k_{12}^{(1)} & k_{13}^{(1)} & k_{14}^{(1)} & 0  & 0  \\ k_{21}^{(1)} & k_{22}^{(1)} & k_{23}^{(1)} & k_{24}^{(1)} & 0  & 0  \\ k_{31}^{(1)} & k_{32}^{(1)}  & a  & b & k_{13}^{(2)} & k_{14}^{(2)} \\ k_{41}^{(1)} & k_{42}^{(1)}  & c  & d  & k_{23}^{(2)} & k_{24}^{(2)} \\ 0 & 0 & k_{31}^{(2)} & k_{32}^{(2)} & k_{33}^{(2)} & k_{34}^{(2)}  \\ 0 & 0 & k_{41}^{(2)} & k_{42}^{(2)} & k_{43}^{(2)} & k_{44}^{(2)}  \\ \end{bmatrix} $$ = $$\begin{bmatrix} K_{11} & K_{12} & K_{13} & K_{14} & K_{15}  & K_{16}  \\ K_{21} & K_{22} & K_{23} & K_{24} & K_{25}  & K_{26}  \\ K_{31} & K_{32} & K_{33} & K_{34} & K_{35}  & K_{36}  \\ K_{41} & K_{42} & K_{43} & K_{44} & K_{45}  & K_{46}  \\ K_{51} & K_{52} & K_{53} & K_{54} & K_{55}  & K_{56}  \\ K_{61} & K_{62} & K_{63} & K_{64} & K_{65}  & K_{66}  \\ \end{bmatrix} $$

where $$ a=k_{33}^{(1)}+k_{11}^{(2)}, b=k_{34}^{(1)}+k_{12}^{(2)}, c=k_{43}^{(1)}+k_{21}^{(2)}, d=k_{44}^{(1)}+k_{22}^{(2)}$$ and $$K_{11}= k_{11}^{(1)}, K_{12}=k_{12}^{(1)}...K_{33}=a=k_{33}^{(1)}+k_{11}^{(2)},K_{34}=b=k_{34}^{(1)}+k_{12}^{(2)}...$$ The numeric values of the global stiffness matrix are as follows: $$K_{11}=\frac{9}{16},K_{12}=\frac{3\sqrt{3}}{16},K_{33}=\frac{9}{16}+\frac{5}{2},K_{34}=\frac{3\sqrt{3}}{16}-\frac{5}{2}, K_{44}=\frac{3}{16}+\frac{5}{2}$$ Applying the boundary conditions where the global nodes one and three are fixed due to the pinned joints ($$d_1=d_2=d_5=d_6=0$$). Thus, elimination of known displacement degrees of freedom it is possible to reduce the global force displacement relationship leaving $$d_3 and d_4$$ to be unknown. Removing $$d_1, d_2, d_5$$ and $$d_6$$ is like replacing columns 1,2,5,6 with zeros because of matrix algebra.

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User:Eml4500.f08.FEABBQ.Jayma/notes1

Class Notes: September 17, 2008
Certain degrees of freedom in our example problem are already known; the boundary conditions set these displacements to equal zero, while the displacements of global node 2 are to be determined. Setting $$ d_1 = d_2 = d_5 = d_6 =0 $$ is the same as deleting columns 1, 2, 5 and 6 in the stiffness matrix. Shown below are columns 3 and 4 and the simplified displacement vector..

$$\underline{K}\left[ \begin{array}{l} d_1=0 \\ d_2=0 \\ d_3=? \\ d_4=? \\ d_5=0 \\ d_6=0 \end{array} \right]= \left[ \begin{array}{ll} K_{13} & K_{14} \\ K_{23} & K_{24} \\ K_{33} & K_{34} \\ K_{43} & K_{44} \\ K_{53} & K_{54} \\ K_{63} & K_{64} \end{array} \right] \left[ \begin{array}{ll} d_3 \\ d_4 \end{array} \right] = \underline{F} $$

Since the stiffness matrix reduces down to a 6-by-2 size and the displacement reduces to a 2-by-1 matrix, the resulting force matrix will have dimensions 6-by-1.

Further reduction of this system of matrices can be performed by the Principal of Virtual Work, which allows us to delete the same rows from the stiffness matrix as we did the columns (1, 2, 5 and 6) as shown below.

$$\left[ \begin{array}{ll} K_{33} & K_{34} \\ K_{43} & K_{44} \end{array} \right] \left[ \begin{array}{l} d_3 \\ d_4 \end{array} \right] = \left[ \begin{array}{c} F_3=0 \\ F_4=P=7 \end{array} \right] $$

Since the goal now is to determine the displacements $$d_3$$ and $$d_4$$, we can rearrange the equation above to solve for these displacements.

$$\left[ \begin{array}{l} d_3 \\ d_4 \end{array} \right] = \underline{\overline{K}}^{-1} \left[ \begin{array}{c} 0 \\ P \end{array} \right] $$

We now have an inverse matrix. As a review...

$$\underline{\overline{K}}^{(-1)} = \dfrac{1}{det(\underline{\overline{K}})} \left[ \begin{array}{cc} K_{44} & -K_{34} \\ -K_{43} & K_{33} \end{array} \right]; det(\underline{\overline{K}}) = K_{33}K_{44}-K_{34}K_{43}$$

With the values $$K_{34} = K_{43} = -2.175$$, $$K_{33} = 3.0625$$ and $$ K_{44} = 2.6875 $$, we have

$$det(\underline{\overline{K}}) = 3.0625(2.6875)-(-2.175)(-2.175) = 3.4998$$

$$\underline{\overline{K}}^{(-1)} = \left[ \begin{array}{cc} 2.6875/3.4998 & 2.175/3.4998 \\ 2.175/3.4998 & 3.0625/3.4998 \end{array} \right] = \left[ \begin{array}{ll} 0.76790 & 0.62146 \\ 0.62146 & 0.87505 \end{array} \right] $$

$$\left[ \begin{array}{l} d_3 \\ d_4 \end{array} \right] = \left[ \begin{array}{ll} 0.76790 & 0.62146 \\ 0.62146 & 0.87505 \end{array} \right] \left[ \begin{array}{c} 0 \\ 7 \end{array} \right] = \left[ \begin{array}{cc} 4.35022 \\ 6.12535 \end{array} \right]$$

Since finding the inverse stiffness matrix was the prominent calculation, it is worthwhile to check the solution, especially given such a simple check as shown below.

$$\underline{\overline{K}}(\underline{\overline{K}}^{-1})=\underline{\overline{K}}^{-1}(\underline{\overline{K}})=\underline{I}=\left[ \begin{array}{cc} 1 & 0 \\ 0 & 1 \end{array} \right]$$

The $$\underline{I}$$ above is called the Identity Matrix and results when a matrix is multiplied by it's own inverse.

 * A special note about the transpose of a matrix...

$$\underline{\overline{K}}^{T} = \left[ \begin{array}{cc} K_{33} & K_{43} \\ K_{34} & K_{44} \end{array} \right] $$

The transpose of the matrix $$\underline{\overline{K}}$$ is not the same as the matrix appearing in the $$\underline{\overline{K}}^{-1}$$ equation.

In order to compare to Statics, we compute the reaction forces.

5) Compute Reactions
We use two methods:

5.1) Use the element Force-Displacement relationships; $$\underline{k}^{(e)}\underline{d}^{(e)}=\underline{f}^{(e)}$$, where $$e=1,2$$.

Element 1 (e=1)

$$\underline{k}^{(1)}\underline{d}^{(1)}=\underline{f}^{(1)}$$. The contents of the stiffness matrix were previously calculated, and the displacement matrix is complete from our calculations above for the global displacements, while the force matrix is only partially known.

$$\underline{d}^{(1)}=\left[ \begin{array}{c} 0\\0\\4.352\\6.1271 \end{array} \right]$$

 * Image goes here

Element 2 (e=2)

$$\underline{k}^{(2)}\underline{d}^{(2)}=\underline{f}^{(2)}$$.

title: User:Eml4500.f08.FEABBQ.Jayma/notes1


text:
User:Eml4500.f08.FEABBQ.Jayma/HW1

Jose's Contribution to HW#1
This is me finishing what Grant started...

Section 19 - Sparse Matrix Computations
Matlab typically handles matrices of which the contents are mostly nonzero. These matrices are considered "dense". A matrix with mostly zero entries is considered "sparse" and is worth defining for the possibility of ignoring the zero values and operating on the nonzero values only. The benefit of this is to reduce the memory footprint of the matrix and the computation time. Suppose a matrix is created by the following command, and that the matrix is filled with mostly zeros by the following command, the output of which looks like The nonzero values of the matrix can be easily found with the command, followed by the output, The following commands will return the matrix to it's previous form and check it's storage mode, respectively Sparse matrices can also be generated directly as opposed to calling the sparse function on a full ("dense") matrix. A sparse diagonal matrix can be generated with the  command. The output is similar to calling the. are the sparse analogs of, respectively. A more specific approach would be to define the nonzero values of the sparse matrix individually. For example (followed by output) The nonzero entities were stored in the row vector. Another example of directly defining the nonzero values of a sparse matrix is The output of Matlab arithmetic and functions will be in one of the two storage modes (either Full(F) or Sparse(S)). The following defines the output results of the manipulation done to either full or sparse matrices

title: User:Eml4500.f08.FEABBQ.Jayma/HW1


title: File:Element1234.JPG


title: File:Element123.JPG


text: File:Starttruss.JPG

title: File:Starttruss.JPG


text: File:Starttrussfinite.JPG

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Empathy

Empathy is one way an individual can react to another individual’s situation, and in particular is about the extent to which that person can understand other peoples' perspectives (Davis, 1983).

Reference
Davis, M, H. (1983). Measuring individual differences in empathy: Evidence for a 	multidimensional approach. Journal of Personality and Social Psychology, 44, 113-126.

title: Empathy


text:
Golf

Golf is a game in which a golfer uses clubs and a ball and moves the ball with strokes down a hole from a tee ground through the fairway into a cup on the green, taking the fewest strokes over 18 holes in a round.

Rules of the game
The game is played according to official rules promulgated by the Royal and Ancient Golf Club of Saint Andrews for the UK and the world and by the United States Golf Association for the US.

Learning to play
Learning how to play the game of golf consists primarily in learning how to make effective strokes with the "full swing" clubs (drivers and irons and wedges) and with the putter. Traditionally and by rule, golf strokes are made while standing beside the ball, and golf is essentially a game of moving the ball "sideways", whether by left-handed or right-handed play. The rules limit the total number of clubs that may be used in a round to 14, and the clubs must each conform to the rules. As a practical matter, almost all golfers choose to play either left-handed or right-handed clubs, but a few golfers occasionally mix left- and right-handed clubs in the same set for a round.

Clubs
The conventional set of golf clubs includes a driver, a 3-wood, a 5-wood, irons ranging from a 2-iron to a 9-iron, a pitching wedge, a sand wedge, and a putter. Modern variant sets typically replace the 5-wood and 2-iron with a hybrid or rescue club and a lob wedge. Each club in the set is designed to send the ball over successive ranges. The driver typically is used to send the ball 240-260 yards, and many professional players average 280 yards per drive. Each successive club in a set from driver to putter is shorter in length and sends the ball a shorter distance, with the idea that the various distances called for during the round can be played with a appropriate club without much adjustment from its customary range.

Courses
Golf courses with 18 holes typically are 6,000 to 7,000 yards in length. A "par" score is set for each course and is usually 72 strokes for the round of 18 holes. Holes may have a "par" score of 3, 4, or 5 (although the rules do not prohibit greater or lesser par scores for holes). Professional golfers often average a few strokes fewer than "par" whereas amateur golfers average as a group around 100 strokes per round. Amateur golfer each may establish a personal "handicap" for competitive purposes that reflects the current level of skill in terms of typical scores. A golfer who typically scores 100 strokes would have a handicap of 28 versus par of 72. A "scratch" golfer has a handicap of zero or perhaps a +2 handicap, representing an average of 2 strokes fewer than par.

title: Golf


text:
Draft:Original research/Culture

Mead (1955) said that culture “is an abstraction of the body of learned behaviour which a group of people who share the same tradition transmit entire to their children, and, in part, to adult immigrants who become members of the society.”

Theoretical culture
Def.
 * 1) "[t]he arts, customs, and habits that characterize a particular society or nation",
 * 2) "[t]he beliefs, values, behaviour and material objects that constitute a people's way of life",
 * 3) "[a]ny knowledge passed from one generation to the next, not necessarily with respect to human beings", or
 * 4) "[t]he language and peculiarities of a geographical location"

is called a culture.

"A culture is the combination of the language that you speak and the geographical location you belong to. It also includes the way you represent dates, times and currencies."

Culture "refers to all the ways in which human beings overcome their original barbarism, and through artifice, become fully human."

"The very word culture meant 'place tilled' in Middle English, and the same word goes back to Latin colere, 'to inhabit, care for, till, worship' and cultus, 'A cult, especially a religious one.' To be cultural, to have a culture, is to inhabit a place sufficiently intensive to cultivate it—to be responsible for it, to respond to it, to attend to it caringly."

Culture "originally meant the cultivation of the soul or mind, acquires most of its later modern meaning in the writings of the 18th-century German thinkers, who were on various levels developing Rousseau's criticism of "modern liberalism and Enlightenment". Thus a contrast between "culture" and "civilization" is usually implied in these authors, even when not expressed as such."

Culture is "that complex whole which includes knowledge, belief, art, morals, law, custom and any other capabilities and habits acquired by man as a member of society." Alternatively, in a contemporary variant, "Culture is defined as a social domain that emphasizes the practices, discourses and material expressions, which, over time, express the continuities and discontinuities of social meaning of a life held in common.

Culture is "the way of life, especially the general customs and beliefs, of a particular group of people at a particular time."

Terror management theory posits that culture is a series of activities and worldviews that provide humans with the basis for perceiving themselves as "person[s] of worth within the world of meaning"—raising themselves above the merely physical aspects of existence, in order to deny the animal insignificance and death that Homo sapiens became aware of when they acquired a larger brain.

Material culture
The concept of material culture covers the physical expressions of culture, such as technology, architecture and art, whereas the immaterial aspects of culture such as principles of social organization (including practices of political organization and social institutions), mythology, philosophy, literature (both written and oral literature), and science comprise the intangible cultural heritage of a society.

Evolution
Cultural change can be brought about by growth, development, evolution, involution, renovation, reconception, reform, innovation, revivalism, revolution, mutation, progress, diffusion, osmosis, borrowing, eclecticism, syncretism, modernization, indigenization, and transformation.

History
It has been estimated from archaeological data that the human capacity for cumulative culture emerged somewhere between 500,000–170,000 years ago.

29 ways in which cultural change can be brought about, include growth, development, evolution, involution, renovation, reconception, reform, innovation, revivalism, revolution, mutation, progress, diffusion, osmosis, borrowing, eclecticism, syncretism, modernization, indigenization, and transformation.

A model of cultural change can be based on claims and bids, which are judged by their cognitive adequacy and endorsed or not endorsed by the symbolic authority of the cultural community in question.

Cultures are internally affected by both forces encouraging change and forces resisting change which are related to both social structures and natural events, and are involved in the perpetuation of cultural ideas and practices within current structures, which themselves are subject to change.

title: Draft:Original research/Culture


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Help:Abaqus/Abaqus explicit

how can analys acceleration history?

title: Help:Abaqus/Abaqus explicit


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Linear Lie algebras

A linear (or "classical") Lie algebras is a Lie algebra whose elements can be represented as matrices (or linear transformations over some vector space over a field.

Realisation
See also: sl(n) (special linear Lie algebra)

An A-series Lie algebra $$A_n$$ is realised by the ring of n-by-n traceless matrices.

title: Linear Lie algebras


text:
Template:Humphreys-Lie Algebras

James E. Humphreys (1972), Introduction to Lie Algebras and Representation Theory, Springer-Verlag, ISBN 9780387900537

title: Template:Humphreys-Lie Algebras


text:
User talk:Cormaggio/Archive 7

Action research
Hi Cormac,

I would like to spend some time on action research, but i have no internet at home at the moment. I will be connected tomorrow. I will spend more time on it from then on.--Daanschr 09:12, 31 January 2008 (UTC)
 * Thanks very much Daanschr - I've very much appreciated your thoughts so far, and of course it's fine to dip in and out as and when you like. I'll start doing some work on the project page and its subpages after I get a bit more clarity on the Colloquium - and we can use these pages to brainstorm and start planning some concrete steps. Cormaggio talk 09:38, 31 January 2008 (UTC)
 * My suggestion is to arrange regular meetings. I can only be involved in that when i have internet at home. Every meeting can have its own topics for discussion. Three kinds of topics would be very helpfull for the progress: 1) specific tasks for individual participants of the meetings, which will be performed within a certain timeframe. Individual participants are not obliged to perform tasks, but if an individual participant promised to do a task than he should be reminded of it when he didn't perform it. 2) A meeting can be dedicated to analyse a specific topic in a sort of brainstorm session. This way certain philosphical problems can be researched. The tricky part of these kind of discussions is that it will lead to conflicts easily. 3) Thinking of ways to gain new participants from other places.--Daanschr 13:40, 31 January 2008 (UTC)

 * AR - a success story.
 * Hi Cormac. I just wanted to say, I think I'm an early example of success in Action Research. Wikiversity has motivated me to get some stuff straight and head back to school (albeit part time) to study teaching. I have some other stuff in the pan, which I'm hoping a little pushing in this new year will bring some results. And Wikimedia Canada looks like it's starting to get rolling again. I'm not sure this exactly fits the theoretical model of AR, but we can talk theories on WCR. :) Historybuff 03:58, 1 February 2008 (UTC)

Hi Cormac, I was a bit ill last couple of days, but i do have internet at home since today. I saw on the colloquium that the discussion has dried up considerably on friday. I like the idea of SB_Johny, but there needs to be an opportunity to be involved without having sound. Perhaps that can be a topic for a meeting?--Daanschr 18:59, 4 February 2008 (UTC)

 * I'm sorry to hear you've been sick, Daanschr - I hope you've recovered or are on the road to recovery. :-) Yes, the Colloquium discussion has faded a bit - and I've been thinking about how to progress from this point. I think we need to set out a plan of concrete action (or perhaps a number of plans) - and just to clarify, which idea from SB_Johnny did you like? A meeting might help too - and I'm always aware that we need to provide for people who don't have access to audio/visual and other communication tools/platforms, such as yourself (though I think you have access to IRC, right?). I think I'll make a stab at something tomorrow - I've got a meeting with my PhD supervisors tomorrow morning and they might be able to give me some ideas for what to do now. But please don't hesitate in adding your own ideas. :-) Thanks again, Cormaggio talk 19:18, 4 February 2008 (UTC)

 * I was referring to the major proposal he made a few days ago. SB_Johnny wants to build Wikiversity into a platform to combat climate change and war. He wants Wikiversity to get new people for Wikiversity.
 * An important thing to note is that Wikiversity exists out of a random collection of people, mainly from the western world. Communication should be adapted to that, otherwise these people will not understand what is being said. The discussion in the colloquium will be abstract from time to time. Certain topics, like the Greek antiquity or climate change are really appealing to people. What could be done aditionally is that different institutions of Wikiversity will be systematically analysed, something like a department for the development of academic institutions on the internet.--Daanschr 09:05, 5 February 2008 (UTC)

 * Thanks again - I also like SB_Johnny ideas for discussion groups on political (and therefore contested) topics, and I'd like to instigate something along these lines here. (You seem to be interested in conflict - which is great - I'm also very interested in how conflict can lead to learning - both personal and organisational.) On your comments about technology - I'm always aware of keeping a discussion as much as possible on the wiki in order not to exclude anyone - but I'm also aware that other forms of discussions (and mediums) can be more productive in certain ways. I'm certainly not going to stop anyone (nor could I) from using whatever medium they think best - but we should probably keep records of all discussions (logs of IRC chats, recordings of audio chats) and post them to the wiki. More basically, I wonder if we could start exploring what a wiki is good for in facilitating such discussion groups. However, I would also like to raise this (and everything else here) somewhere more public than my talk page. :-) But just on this last post, I agree that Wikiversity is a random collection of people, who are currently predominantly from the western world. But when you say "communication should be adapted to that", are you saying that communication would be somehow only relevant or accessible to the western world? That would be another means of exclusion in my book... Cormaggio talk 13:58, 5 February 2008 (UTC)

I was more referring to the reason why the discussion might have dried up. It was too abstract.

You got a point about wikis. Wikiversity has wiki and university in its name. So, if there will be a lot of chatting and radio listening than maybe it is not wiki enough anymore. I have theorized a certain contradiction to adress this problem, the conflict between quality and participation. These are completely different interests. Stimulating quality (keeping wiki) could mean that only a small group of people are interested. What could be an idea is that the wiki will be the central medium to keep the other media organized together within Wikiversity, but that other media may be used.

A romantic or postmodern answer to what a wiki is good for would be that it depends on who, for what reason and how someone uses a wiki. Nietzsche wrote that it is very hard to establish a method due to laziness and conservatism of people. That it is hard now to get a good working method on Wikiversity doesn't mean that it could be working very good after a century.--Daanschr 14:45, 5 February 2008 (UTC)

 * Gadzooks! "A century" - I'm holding out for something useful somewhat sooner :-) - if simply to point us to what the limitations of a wiki are. This is implied when I ask "what is a wiki good for?" - I'm talking affordances/constraints - but you're right that these will fluctuate to an extent depending on context. Abstract - I like abstract. ;-) However, I'm too tired right now to make a go of developing our discussion so far into a concrete plan - this will have to wait until tomorrow (and I will promise I'll do it then - I had a few other commitments today which took longer than expected). Cormaggio talk 23:13, 5 February 2008 (UTC)

 * Okay, untill later than. ;-)--Daanschr 08:06, 6 February 2008 (UTC)

 * Another idea: Wikiversity could stimulate similar wikis from outside Wikiversity to merge with us. This way, larger communities and networks could emerge. For instance, three of the wikis in this list, which was posted on the colloquium could relate to Wikiversity. There are two wikis dedicated to teachers and one to wild life preservation. Wikiversity could be a networking organization, or an umbrella organization.--Daanschr 08:23, 6 February 2008 (UTC)

 * Cormac, i like to include case-studies and topics dedicated to increase participation. With case-studies, i mean some small topics, which can say something about the bigger picture, the major concepts. A case-study could be a course on Wikiversity, or a certain text reading, which can be discussed with a broader view in mind. Topics dedicated to increase participation have to do with the perception of what others are interested in in our direct environment. For instance, what do Erkan, John and SB-Johnny want and how can we coordinate their wishes. This way we can directly work with the community we serve. What do you think about it?--Daanschr 18:21, 7 February 2008 (UTC)

 * How would such a case study actually work? Do you want to explore an issue through discussion - finding out what people are interested in - and then creating a project around common interests? This is what I hope to do through discussion groups and reading groups, for example the ones I've created recently around the Wikiversity learning model. it would be good if you spelled out clearly what kind of project you're thinking of, and how it would work. But I would really prefer this to move to Talk:Developing Wikiversity through action research - I'm going to copy this discussion there now... Cormaggio talk 21:04, 7 February 2008 (UTC)

 * Cormac, perhaps a good place to actually start looking at a 'case study' would be the reading groups themselves; they seem to me to be an obvious form for a Wikiversity learning project yet they may also reveal a lot to us about how a learning project might be organized, structured, and sustained in the environment. And yes I think that the John Seely Brown readings should be included in the Wikiversity_learning_model/Reading_group. Countrymike 18:47, 8 February 2008 (UTC)

Not sure if this is useful but Lindy McKeown in Qld AU uses action learning as her model for working with SecondLife in education. http://www.lindymckeown.com/index.php?option=com_content&task=view&id=18&Itemid=32

Bots/Status
Can you as bureaucrat please take a look on Bots/Status? -- MichaelFrey 12:39, 9 February 2008 (UTC)

Wikiworld..
I have not read it. But it looks interesting, I will take a look at it. Thank you. It is interesting so far... --Remi 21:58, 10 February 2008 (UTC)

differences of opinion
Sorry about me now being busy in the real world. "learning can equally come from having significant differences of opinion" <-- one of the original ideas for Wikiversity was that it could host "debate clubs". I expected that some Wikiversity projects such as War Seminar might naturally develop into places where Wikipedians could work outside of the stricter restrictions of doing encyclopedia work. Speaking for myself, I've been reluctant to promote Wikiversity as a place for emotional debates, fearing that until Wikiversity gets larger it could be disrupted if a large group of POV warriors decided to turn Wikiversity into a battle ground. Of course, being guided by such fears cuts Wikiversity off from a key approach to attracting dynamic groups of participants. I do hope that Wikiversity will eventually be strong enough to host scholarly debates that will be both 1) attractive to some Wikipedians and 2) civilized enough to result in the construction of useful learning resources and learning communities. --JWS 14:06, 11 February 2008 (UTC)

currency
Since it is almost a straight copy of wikipedia, I will change some of the words. Before you told me this, for the paper currency pages, instead of paragraphs on small sized notes, I made a list like the large size notes. On the coins pages, instead of tables? I made them into paragraphs. Those are some of the changes I made for the additions of these pages. On the $2 bill page, I also took out some things. They were not really about the $2 bill. And I wanted to make these United States currency pages "educational". I also have a question— whenever I go to my preferences and change the time zone to EST, it always comes out as UTC when I do -~. How do I really fix this problem?

-km 00:49, 17 February 2008 (UTC)

Topic:Traditional Satanism Studies
Do you think this Topic:Traditional Satanism Studies is appropriate for Wikiversity? --Remi 20:31, 22 February 2008 (UTC)

I asked the same question of Erkan, which led to a debate, which led to Learning Resources. --McCormack 16:04, 29 February 2008 (UTC)
 * Unfortunately I do not have a chat history, but I am definitely for keeping that material. There are various reasons - I could state again here, but I hope McCormack has a chat history. I think we thought about to ask the user and also make a non-influencing template ? Erkan Yilmaz Wikiversity:Chat  16:10, 29 February 2008 (UTC)

 * That's interesting - thanks for the context. :-) Cormaggio talk 16:27, 29 February 2008 (UTC)

Another Seely-Brown gem
see: http://connect.educause.edu/Library/EDUCAUSE+Review/MindsonFireOpenEducationt/45823 Countrymike 06:44, 24 February 2008 (UTC)

Wording
Yes - that wording is better! --McCormack 16:03, 29 February 2008 (UTC)

Presentation pics are up, 7 months late
They're here - http://melchua.com/tmp/cormaggio-presentation.zip - do anything you want with them (I hereby release those photos CC-BY). Feel free to host them anywhere you like - just let me know when you've yoinked the files so I don't have to worry about keeping them on my server forever. :) Mchua 05:29, 2 March 2008 (UTC)
 * I'll try to look in on those links you mentioned - life is finally settling down that I've stopped traveling and moved into Manhattan, so with any luck my presence on Wikiversity will pick up. Mchua 05:29, 2 March 2008 (UTC)

BCP page creation
Hi Cormaggio, Just saw this!

See http://en.wikiversity.org/w/index.php?title=BCP/Narcissus_pseudonarcissus&action=history

The first edit I made was replacing the page using Narcissus pseudonarcissus, the second edit was making the log page (see that diff for the directions), and the third one was to add info to the templates.

Anything blooming for march? ;-) --SB_Johnny | talk 11:59, 8 March 2008 (UTC)

 * BTW: I started your keys: Bloom Clock/Keys/Manchester, England/November/All. --SB_Johnny | talk 18:15, 12 March 2008 (UTC)

Username rename
I'd like my account User:Cool Cat be renamed to User:White Cat as per my wikimedia-wide username rename, thanks. -- Cat chi? 17:43, 12 March 2008 (UTC)
 * Done. Cormaggio talk 17:56, 12 March 2008 (UTC)

 * Hey... a bit of silliness on wikibooks brought it to my attention that you might not have confirmed that username change. Just a heads up to be careful about that: it's not absolutely unheard of (cough, cough) for ill-intentioned people to make bad faith requests for username usurpation :). I generally ask them to confirm a message on their wikipedia or commons userpage. --SB_Johnny | talk 18:30, 12 March 2008 (UTC)

 * If someone is asking for a usurp, I generally will go to WP first to check who has the account name there, or commons if there is no active account there (the latter case usually means they are contributing more in another language). The I just ask them to confirm that they're the one asking on their talk page (while logged in, etc.). We had some problems for a while with banned users on Wikibooks registering accounts using Wikipedia administrators' usernames and then vandalizing with them... likely to happen on Wikiversity as well as things go on.
 * There is a tool for checking a username across all wikimedia foundation wikis, but honestly I forget the link (will try to find it). checking en.wp almost always comes up with the result though :-). --SB_Johnny | talk 00:36, 13 March 2008 (UTC)
 * Here it is: http://tools.wikimedia.de/~luxo/contributions/contributions.php  --SB_Johnny | talk 00:49, 13 March 2008 (UTC)

Bot account

 * No idea what the above is about, but did anyone notice this? --mikeu talk 02:32, 13 March 2008 (UTC)
 * Yup, the user is doing this atm at many places. See also Bots/Status Erkan Yilmaz Wikiversity:Chat  07:27, 13 March 2008 (UTC)

Teaching with Technology
FYI, here are some links you might be interested in. I'll be attending a workshop next week on Enhancing Student Engagement: the WIKI Collaborative Workspace. There are some interesting related links here. One of the presenters is Mark Tribe who is teaching classes on Digital Art and Open Source Culture this semester. He also has a Wiki for Teaching and Research. I'll post some notes after the session. --mikeu talk 10:31, 14 March 2008 (UTC)

Username
Thanks Cormaggio, for changing my username. Terra What do you want? 21:42, 14 March 2008 (UTC)

Please change usergroup
Hi Cormac. Please change the usergroup for User:Terra from (none) to (sysop), so I can start his mentorship :). --SB_Johnny | talk 09:27, 17 March 2008 (UTC)

Bloom Clock instructions
Hey Cormac. Here's a couple answers for you... I'm going to try to answer as many questions as possible using subpages rather than plain text talk pages, in the hopes of getting the material together for the instructin manual. text below is included from User:SBJ/Bloom clock delayed logging and User:SBJ/Bloom clock multi-location

--SB_Johnny | talk 09:55, 17 March 2008 (UTC)

Dutch Wikimedians
Hi Cormac,

Thanks for the suggestions. It isn't a good moment for this, because i get a new job and will have far less access to internet. I will wait for a few months and than i could be interested in it. I just don't know how my job will be like. It will be my first fulltime job with very little access to computers.--Daanschr 11:20, 18 March 2008 (UTC)

 * I will be around, but i don't know how often. Duty calls.--Daanschr 12:19, 18 March 2008 (UTC)

ping
Are you around to WV:CHAT? --mikeu talk 11:51, 18 March 2008 (UTC)

FYI, w:User:Jbmurray/Madness "Reflections on the use of wikipedia in the University of British Columbia's course SPAN312, "Murder, Madness, and Mayhem: Latin American Literature in Translation," Spring 2008." --mikeu talk 22:42, 18 March 2008 (UTC)

Leaflet
Yes, I would like to help with poster/leaflet so I can plaster it up and down the corridors. Your excellent A3 pdf post - can we hack it? Could you post a non-pdf version? I'll have a look at the leaflet notes. Perhaps in the process we could help improve Wikiversity too. -- Jtneill - Talk 13:49, 19 March 2008 (UTC)
 * I did some work just now. Maybe we can play bat and ball for a bit. I don't know the format for the poster, but I'm curious. Is it an open format I could edit with free software? If not, perhaps we can find such a format. I don't know what that could be except .odg. But anyway, the only real edit I thought was perhaps to replace your (beautiful :) ) picture and bio in the bottom right with something more generic. I realise it was for a conference ;). Then I could see myself sneaking into people's offices at night and sticking them up. -- Jtneill - Talk 17:08, 19 March 2008 (UTC)
 * I've added some 'poster' comments - (I'm having problems working out interwiki link to commons??) -- Jtneill - Talk 05:14, 20 March 2008 (UTC)
 * Given difficulties converting old poster format to open format, would you be able to extract the text and images, and upload them, then we can rework into a new open format poster? -- Jtneill - Talk 11:10, 30 March 2008 (UTC)

Draft template for innovative educators
Hi, Cormaggio. You seem to be quite good at making new pages on innovation in education, and also quite good at not linking them into the grand scheme of things! So I have created a navigation template especially for this purpose. Please feel welcome to put this on your pages, and to update the template with your new pages in order to hold everything together. Template:Learning innovation. --McCormack 10:13, 20 March 2008 (UTC)

Request for WV presentation slides
FYI, see Talk:Presentations about Wikiversity. -- Jtneill - Talk 11:17, 21 March 2008 (UTC)

Spam Filter Idiocy
Hi Cor,

I'm really angry. I CANNOT edit anything on my requirements specifications pages EVER because of the automated spam filter. Is there no way to turn this off? I understand the motivation, but this has clearly not been properly thought out before implimentation. Try to edit http://en.wikiversity.org/wiki/Technical_writing_specification in any way at all...nothing works!!! Do I have to start over because boy geniuses don't think before they code? (Maybe they should read about requirements and testing first!!!) Sorry, but I'm really, really, really frustrated and angry that this has happened. TWFred 20:29, 25 March 2008 (UTC)
 * Hi, see the preliminary solution here please. Hope everything fine now ? Erkan Yilmaz uses the Wikiversity:Chat (try) 20:40, 25 March 2008 (UTC)

Cor, Erkan fixed it already. Sorry for the anger. I'm just passionate sometimes about this work, and get frustrated by inexplicable blockages. Best. TWFred 21:06, 25 March 2008 (UTC)

Wikipedia Signpost interview
Signpost is doing a series of interviews about Wikimedia sister projects. Erkan and I have contacted them, but we'd also like to get your input. See Colloquium thread. --mikeu talk 11:17, 27 March 2008 (UTC)
 * Just to reaffirm, when you've got you're feet back on the ground, this interview could really benefit from your input: User:OhanaUnited/Sister Projects Interview. -- Jtneill - Talk 12:32, 1 April 2008 (UTC)
 * Yep, I'm currently reading and keeping note of all the developments that have taken place in my absence! Cormaggio talk 12:47, 1 April 2008 (UTC)

Draft development statement for new main page
Hi Cormaggio. You may remember I solicited your opinion on colours a while back. I can't remember if I asked you to comment on Main_Page/Development_0.5. I decided to rewrite the content of the boxes on the main page in the new draft, and so far nobody has said anything about it! I reckoned you'd be particularly interested in the development box. I don't particularly have any axe to grind with the content of these boxes, other than that at present they are confusing, meandering and unhelpful. --McCormack 16:14, 1 April 2008 (UTC)

 * Hi again. I've reacted to your comments on the talk page for the draft. Can you have a look and respond further? Hope this doesn't disturb your thesis crisis! --McCormack 05:43, 2 April 2008 (UTC)

 * Hi Cormaggio, and thanks for your edits. I was glad to see what you did to the community box in particular. It had a lot of "legacy" hyperlinks which I didn't feel bold enough to do away with. Megalomania is best shared ;-) --McCormack 15:42, 2 April 2008 (UTC)

Another go at WCR?
Hi Cormac,

I'm starting to see the light of day again, and thought it would be a good time to ping you about doing a WCR bit. I'd even be happy to start a text dialog on Education of some sort, whether it be IRC or even talk page stuff. Ping me back and let me know though. Historybuff 07:18, 2 April 2008 (UTC)

 * I was relaxing towards the end of last week; it's good to hear you also got some time off. I'm back in the thick of things now, and sorting things out. Friday is my flex day this week, let me know if anytime works for you on Friday. As for Asterisk, other then the last horrible episode with you, we've had really good previous success. Countrymike (and a couple other down-unders) had zero trouble on the last iteration of this crazy ride, so it's only you I have to solve, I hope. :) I'm happy to use another medium, btw -- skype, gizmo, whatever -- even plain old ma bell if it works, until we have everything running smooth. Historybuff 20:45, 9 April 2008 (UTC)

It looks like I ended up taking an unintentional wikibreak, just being way too busy IRL. There is lots of goings on here on WV it seems, and I'm thrilled at that. I'm hoping I'll have time this week to sit down and configure a spare server which will allow us to have a semi-permanent home for WCR and conferences for courses. (The perm home should be the sandbox server, if I can chat with the people admining it). I'm still promoting WV in real life, despite being not as active as I'd like on the cyber side of things. I have lots of interesting ideas from school, and I think we should have a discussion just on that level -- be it on-wiki or by voice, if you have some time. Historybuff 19:06, 18 May 2008 (UTC)

 * Well, another week has slipped by, and while I've caught up on a bunch of WM related projects I'm interested in, um, WV hasn't been getting lots of love from me. And it's not like I've forgotten it, in fact I'm lobbying for a bunch of WV stuff, but I'm starting to feel like a politician and not a civil servant, if you know what I mean. So, I'm going to start focusing more on getting stuff done here, and doing other stuff in time left over. Do you have any free time next week for a chat? :) Historybuff 01:07, 24 May 2008 (UTC)

Mission statement
Could you offer comment on this User talk:Jtneill. I'm wanting to check whether I am using the official, current mission statement here: Mission/Current. -- Jtneill - Talk 03:23, 12 April 2008 (UTC)

Vision
Could you also take a look at Vision. In particular, could you consider: (a) any original, proposal-type material on WV vision which could be added/linked to from that page; (b) your contributions/thoughts on a draft vision statement -- Jtneill - Talk 03:35, 12 April 2008 (UTC)

Dave + Hal
Yes, that was what I meant :-) Erkan Yilmaz uses the Wikiversity:Chat (try) 13:04, 12 April 2008 (UTC)
 * Cool. :-) Cormaggio talk 14:05, 12 April 2008 (UTC)
 * Actually I didn't knew that Dave earlier - a certain person in the WV:Chat brought my attention to HAL 9000 - before we had the post in the Colloquium. See you later, Erkan Yilmaz uses the Wikiversity:Chat (try) 14:12, 12 April 2008 (UTC)

Copyvios in Design for the Environment course
That was a cut & paste mistake. I pasted the url for a Jeep engine on the fuel cell image page instead of Image:Flex.JPG. I am pretty sure that the fuel cell is also a copyvio, but I don't yet know the source. --mikeu talk 18:15, 14 April 2008 (UTC)

 * BTW, we have the same problem with the students at Introduction to Computers. There are still a lot of images in those pages that need to get looked at.  See also User:Mu301/todo for general image cleanup I've been doing.  (removing duplicates, copying to commons, etc.)  --mikeu talk 11:00, 15 April 2008 (UTC)

 * We should probably leave a note for User talk:SRego about the images used in DFE pages. It looks like he will be doing this again next semester.  --mikeu talk 11:07, 15 April 2008 (UTC)

Jtneill
Hi, Cormac. Can you activate sysop status for User:jtneill to that he can start his probationary custodianship? Thanks. --McCormack 09:29, 16 April 2008 (UTC)
 * Thanks! --McCormack 09:40, 16 April 2008 (UTC)

 * Thanks for the support and activation; I'm underway. Sincerely, -- Jtneill - Talk 13:13, 16 April 2008 (UTC)

New main page
Hi, Cormac. I see you're busy uploading screenshots. I'm thinking of activating the new main page, notwithstanding layout issues - we can always tweak those later. Any last minute objections? I've talked to quite a lot of people both on IRC and the colloquium, and the general feeling is very good, although with questions and minor points. Did you see the FAQ I created? --McCormack 12:21, 21 April 2008 (UTC)

 * Here: Main page learning project/April 2008 Redesign --McCormack 12:27, 21 April 2008 (UTC)

re:Structuring
Yeah, I've been informed quite a few times on IRC already :-)... honestly I think the namespaces were a silly idea from the start, but I'm also not particularly interested in the subject right now. I'm pretty busy on the farm, etc., and really only have time for the Bloom Clock (etc.) these days. --SB_Johnny | talk 16:56, 27 April 2008 (UTC)

 * Oh, no apologies necessary at all! It's nice to see you being involved :-). --SB_Johnny | talk 00:25, 28 April 2008 (UTC)

`

Wikimedia Radio..
Please see n:WN:RADIO Urgently :) 62.56.54.110 20:19, 27 April 2008 (UTC)

namespaces
Thanks for the note on my talk page. A couple of the most interesting and surprising things for me about the wiki world have been 1) the invention of organized content development projects (in the form of "wikiprojects" at Wikipedia) and, 2) the fact that most people do not seem to care about organized content development projects. Given my past experience with the limited success of wikiprojects within the much larger community of Wikipedia, I cannot say that I have been surprised by how hard it has been to get the Wikiversity community to utilize the school and topic mamespaces as places for organized content development projects. I guess its just one of those things that will only ever be of interest to a minority group. For several years I wondered why wikiprojects were so well hidden at Wikipedia....I guess they are just one of those things that it is best to hide away in a safe place where hopefully the majority will ignore it rather than try to vote it out of existence. --JWSchmidt 04:13, 28 April 2008 (UTC)

Schedule
Yup, that's the only time I know for sure I'm free (that's 4-5:30 AM here). I'd say don't try to schedule around me... even that time period can be unpredictable depending on how the goats behave. Otherwise I'm really just here when I happen to be here (if you can perhaps schedule it for the next day it rains (or perhaps wait until December through February), I'll be available most any time :-). --SB_Johnny | talk 15:37, 30 April 2008 (UTC)

mentat wiki month
Mentat wiki month looks like it's going to be a nifty adventure. We've got some of the original authors of the mentat wiki on there, too. Mchua 20:18, 5 May 2008 (UTC)

Random mascot welcome
 Hi! Our name is Vicky-Verity. We are twins and are Wikiversity mascots. We think Wikiversity is a great place to learn and make friends (when we aren't sleeping). Leave us a message!

Project boxes
Hi, Cormaggio. Thanks for your encouraging feedback! I reckoned you'd like this. Actually the idea has been in my head for a very long time. A lot of the things I've been doing on WV in the last couple of months have been kind of embryonic for the last year. The project boxes are already catching on. User:Robert Elliott seems to be quite encouraged by this kind of infrastructure, as does User:Fasten. Now, if you'd like to tag your own initiatives and projects...! Perhaps we need a box for resources of type "Template:exploratory thoughts"? Or even "Template:PhD snippets"? --McCormack 12:54, 11 May 2008 (UTC)

Meetings
Hi Cormac, did you have already some chats with someone or feedback from other participants about a date ? Erkan Yilmaz uses the Wikiversity:Chat (try) PS: Tag a learning project with completion status !! 15:29, 25 May 2008 (UTC)

Username change
Compwhizii → CWii

It's for SUL. Thanks, Compwhizii 01:11, 27 May 2008 (UTC)

Checkuser
Hi Cormac, there were set up now 2 new pages for the voting. Erkan Yilmaz uses the Wikiversity:Chat (try) PS: Tag a learning project with completion status !! 21:49, 28 May 2008 (UTC)

Quote "It's not that easy boy"
Hi, Cormac. If you wish to put it back, fine. I reckoned it detracted from your very sensible contribution below. The comment was added by an anonymous user, unsigned, rather poor choice of language, unexplained, etc.... I'd call it borderline vandalism, and I didn't really like seeing it hovering above your serious contribution. But add it back if you like. --McCormack 14:58, 31 May 2008 (UTC)

re: IRC meeting
I saw. My schedule at this time of year is far too unpredictable for me to commit to any time, but I'll try to pop in whenever you set the time. --SB_Johnny | talk 14:45, 1 June 2008 (UTC)
 * Hi Cormac, I have send you an additional email, Erkan Yilmaz uses the Wikiversity:Chat (try) PS: Tag a learning project with completion status !! 06:35, 4 June 2008 (UTC)

RussBot and more than double redirects

 * Hi, I'm wondering does RussBot work on more than double redirects (ie triple, quadruple redirects)? It would be great to have that function. In any case, we're looking for something that cleans up redirects on Wikiversity. Would the bot script need to be modified for use there, and if so, would it be possible for you to do so? You're more likely to reach me on my WV talk page, but I do also check WP. Thanks! Cormaggio is learning 10:02, 5 June 2008 (UTC)

 * Yes, the bot script can handle double-redirects on Wikiversity if you want, and it should be able to detect triple- and quadruple-redirects (although I can't imagine that would be a big problem; even on en.wikipedia.org, which has exponentially more double-redirects than any other project that I know of, triple-redirects occur very rarely). --R'n'B 12:58, 5 June 2008 (UTC)

Well, I can just run the bot myself (once I get around to activating SUL for it), or you could install Pywikipediabot on your own machine and run the redirect.py script. Are you looking to cover just this wiki, or all of the *.wikiversity.org sites? --R'n'B 15:48, 5 June 2008 (UTC)

It makes no difference to me. I'll give the bot a try sometime within the next few days. I must confess, however, to some curiosity about this request--according to Special:DoubleRedirects, there were only 5 doubles at the last update, so what's the big deal? --R'n'B 20:14, 5 June 2008 (UTC)

 * User:RussBot is now SUL'ed, so you might want to give it the bot flag on this wiki. But it can run either with or without the flag, I believe.  --R'n'B 20:50, 5 June 2008 (UTC)

 * Of course, you should monitor the account's contributions to make sure it doesn't (or I don't) go bezerk. :) FYI, I ran a complete scan on this wiki yesterday and found ZERO double-redirects.  The person who originally raised this issue on the discussion page either was mistaken or was addressing a problem that has since been fixed by other users.  --R'n'B 13:54, 6 June 2008 (UTC)

SUL
I want to usurp user:orion(no contribution)for SUL account unification and vandal prevention. I'm a active editor of zh:user:orion,The confirmation here,Thank You.--Orionn 07:04, 6 June 2008 (UTC)
 * Please go to Changing_username: please request there (also by pointing then with a link to the request from your home wiki - the one given above just proves, that that user made an edit, nothing else) and insert Template:Usurpation requested by using on the user talk page to start the process. Erkan Yilmaz uses the Wikiversity:Chat (try) PS: Tag a learning project with completion status !! 15:34, 6 June 2008 (UTC)

Name...
SUL is nice. But yes, it seems SUL logs me out of User:Remi when I sign in on Emesee on other projects, and vice versa. I'm not really using accounts for different types of edits, so to speak. When I need to perform custodial actions it hasn't seemed to be much of a hassle just to re-login so far. If changing flags to this username in the future is an option, that would be nice. --Emesee 10:32, 8 June 2008 (UTC)

Action research
I recently found Developing Wikiversity through action research/List of uses of Wikiversity, which suggested an answer to a question that had been occupying me lately - the question being: is what I've been doing recently with things like Help:Resource types and its related pages (i.e. empirical analysis of existing resource types aims at producing a taxonomy with which to advise new contributors on possible uses of WV) something which qualifies as a low brow form of "action research"? --McCormack 12:31, 9 June 2008 (UTC)

"betawikiversity closure vote isn't going anywhere"
Hi Cormac, as you know written language is ambiguous: I am not sure if I understood in full what that means ? You mean that beta will not be closed and therefore we don't need to make others aware anymore about the current proposal which is still ongoing ? Erkan Yilmaz uses the Chat (try) 15:24, 10 June 2008 (UTC)

Custodian flag
If we can keep User:Remi and User:Emesee both flagged as custodians, please make the switch for this username. It may make things easier for the time being. Thanks. --Emesee 03:30, 15 June 2008 (UTC)
 * Hi, just a remark: User:Remi0o has also custodian flag: . Then this would mean there would be 3 accounts which belong to you with custodian flag :-)
 * Remi, why not use one custodian user account - is there a specific reason ? Erkan Yilmaz uses the Chat (try) 15:38, 15 June 2008 (UTC)
 * ah - well one option would be also to use the User:Remi0o account instead ? Erkan Yilmaz uses the Chat (try) 16:04, 15 June 2008 (UTC)
 * see here, Erkan Yilmaz uses the Chat (try) 08:22, 21 June 2008 (UTC)
 * ping, Erkan Yilmaz uses the Chat (try) 16:50, 23 June 2008 (UTC)

log about last meeting (7th June 2008)
In case you didn't receive my mail: when will it be published ? Erkan Yilmaz uses the Chat (try) 15:41, 15 June 2008 (UTC)
 * see my mail please, Erkan Yilmaz uses the Chat (try) 19:34, 19 June 2008 (UTC)

Welcome back
Hi Cormac. Hope you had a good holiday. Loads of new stuff on WV for you to catch up on. In the talk pages of some of my help pages for specific resource types, I have been noting down how the resource type concept originated, as I take it this would be of interest to action research. --McCormack 09:45, 24 June 2008 (UTC)

http://en.wikiversity.org/wiki/Photoproject#New_Camera Elatanatari 22:38, 24 June 2008 (UTC)

Thoughts on a clock:
See User:SBJ/Produce clock. Interested? --SB_Johnny | talk 14:12, 25 June 2008 (UTC)

Vision statement
Do we have an authoritative vision statement yet? --McCormack 07:46, 29 June 2008 (UTC)

Wiki research
I added what I thought might be an amusing image at the top of Help:How to write an educational resource, and then wondered if I should re-think! Well, I have this thinking problem... I think I wasn't thinking when I thought it up. What do you think? --McCormack 18:23, 4 July 2008 (UTC)
 * I found the image funny - thinking to use it elsewhere also :-) Erkan Yilmaz uses the Chat (try) 20:41, 4 July 2008 (UTC)
 * Nice image! I think the explanatory tag is also good - but I wonder if the image itself would be better placed on another page which is more explicitly about "the use of wikis in web-based education"? Surely we (ie humans) know a little bit more about writing educational resources? :-) Cormaggio talk 11:17, 7 July 2008 (UTC)
 * "better placed on another page which is more explicitly about..." --> the image can, of course, be used many times, but how about Template:Welcome? --McCormack 11:26, 7 July 2008 (UTC)
 * Using it on Template:Welcome just might send out the wrong message ("old-timers consider newcomers as monkeys") - although a fresh eye over that template makes me think we need to emphasise that we are genuinely engaged in an act of exploration with regard to wiki-based learning, and we invite others to join that process. Where's the best place (existing or imagined) to link newcomers to to inspire this engagement? I also think the image would be better off on somewhere like Learning or FAQ (or perhaps a newly articulated space) than the welcome template, or indeed where it is now... Cormaggio talk 11:49, 7 July 2008 (UTC)
 * I'm afraid I was kidding with Template:Welcome. Being serious for a moment, images do liven up the help pages, especially if they are slightly whacky or tongue-in-cheek. But if one tries that kind of thing, one has to be careful to strike exactly the right note. Humour is a dangerous thing. For example, the 4 port-a-loos to symbolize the 4 P's of lesson structure might be going too far. --McCormack 12:35, 7 July 2008 (UTC)
 * Yup. :-) I think that's why humorous images need to be set in just the right context, and framed by just the right explanation/tone - in order to communicate the fun that they're about, as well as the at least semi-serious point behind them. I'm afraid I once again fell into the trap of taking you too seriously. :-) Cormaggio talk 21:48, 7 July 2008 (UTC)

Blog
Hi Cormaggio. The wiki2blog feature is too buggy for general use, so it's not something Wikia is going to continue running. We might pick it up again in the future, but for now, you might want to delete the demo page at MediaWiki:Blog snippet which was feeding into the test blog. Angela 05:58, 30 July 2008 (UTC)
 * Thanks - done now. Cormaggio talk 10:39, 30 July 2008 (UTC)

title: User talk:Cormaggio/Archive 7


text:
Stigma

The term “stigma” originated from the Ancient Greek word "stigmata" which referred to “bodily signs designed to expose something unusual and bad about the moral status of the signifier” (Goffman, 1963, p. 11). There are varying definitions of stigma, however, reflecting the phenomenon’s complexity. One conceptualisation is that it refers to the “labelling, stereotyping, separating, status loss, and discrimination" (Link & Phelan, 2001, p.382) which co-occurs in power situations in such a way that leads to interrelated, negative social consequences for the stigmatee(s).

Activities

 * Examples - on this page, contribute to and discuss examples of stigmatisation

title: Stigma


text:
User:Eas4200c.f08.spars.lee

=Homework 2= See: Homework 2

=Homework 3= See: Homework 3

=Homework 4= See: Homework 4

=Homework 5= See: Homework 5

title: User:Eas4200c.f08.spars.lee


text:
User:Eas4200c.f08.spars.lee/Homework 2

=Problem 1.1=

"1.1 The beam of a rectangular thin-walled section (i.e. t is very small) is designed to carry both bending moment M and torque T. If the total wall contour length L = 2(a + b) (see Fig. 1.16) is fixed, find the optimum b/a ratio to achieve the most efficient section if M = T and $\sigma$allowable = 2$\tau$allowable. (Sun p. 17)"

Assumptions
There are four assumptions made in the problem statement.

Assumption 1:   $$\mathbf{L} = 2\mathbf{(a + b)} $$

Assumption 2:      $$\mathbf{M} = \mathbf{T} $$

Assumption 3:     $$\ \sigma_{allowable} = 2\tau_{allowable} $$

Assumption 4:     $$\ \mathbf{t<<a},\mathbf{t<<b}$$

Shear stress

 * The first step is to determine the relationship between the shear stress, $$\tau$$, and the torque, T. In actuality the shear stress takes a parabolic shape as shown in figure, but in this case since the thickness is very thin (assumption 4) the shear force can be approximated by a uniformly distributed shear flow q.

 * q = $$\tau$$t (3.47)

 * Where the shear flow is related to torque by,

 * dT = ρq ds

 * where ρ is equal to the lever arm and ds is the differential length of the very thin bar. Integrating, this equation becomes

 * T = ρqS

 * The torque in this problem can be broken up into the sum of the torques in each side, T = TAB + TBC + TCD + TDA. By symmetry TAB = TCD and TBC = TDA which simplifies the equation.

 * TAB = $$\frac{b}{2} (q\cdot a) = \frac{\tau abt}{2} $$

 * TAB = $$\frac{a}{2} (q\cdot b) = \frac{\tau abt}{2} $$

 * Therefore

 * T = $$ \mathbf{2\tau a b t} $$

 * $$ \tau = \frac{T}{2abt} $$

 * This is identical to to equation provided in the problem statement with no explaination.

Solution

 * In order to solve this problem it is necessary to consider two cases.

Case One

 * Assume the bending normal stress, $$ \sigma $$, reaches $$ \sigma_{allowable} $$ before shear stress, $$ \tau $$, reaches $$ \tau_{allowable} $$.
 * Recalling that the bending normal stress is related to the bending moment by ordinate of a point on an axis perpendicular to the bending neutral axis over the second moment of inertia according to the equation

 * $$ \sigma = \frac{Mz}{I} $$

 * From which the following relationship is derived

 * $$ \sigma_{allowable} = \frac{M_{max}b}{2I} $$ → $$ M_{max} = \frac{2I\sigma_{allowable}}{b} = 2\sigma_{allowable} (\frac{I}{b})_{max} $$

 * The second moment of inertia is represented by

 * $$ I = \sum_{i=1}^{4}{[\frac{b_i(h_i)^3}{12} + A_id_i^2]} = 2[\frac{tb^3}{12} + \frac{at^3}{12} + \frac{atb^2}{4}] = 2[\frac{tb^3}{12} + \frac{at}{12}(t^2 + 3b^2)]$$

 * Assuming that t is very small compared to b this equation can be approximated by

 * $$ I = 2[\frac{tb^3}{12} + \frac{3atb^2}{12}] = \frac{tb^2}{6}[b + 3a] $$

 * Recalling assumption 1 ($$ L = 2(a + b) $$) the variable a can be stated as

 * $$ a = \frac{L}{2} - b $$

 * Which can then be used to express the second moment of inertia in terms of a single unknown variable b

 * $$ \frac{tb^2}{6}[3(\frac{L}{2} - b) + b] = \frac{tb^2}{6}[\frac{3L}{2} - 2b] = \frac{tb^2(3L - 4b)}{12} = \frac{1}{12}[-4tb^3 + 3Ltb^2]$$

 * Returning to the equation for Mmax it is evident that $$ 2\sigma_{allowable}$$ is a constant and therefore Mmax is maximized when $$ (\frac{I}{b}) $$ is maximized.

 * $$ f(b) := \frac{I}{b} = \frac{1}{12}[-4tb^2 + 3Ltb]$$
 * $$ f'(b) = -\frac{8tb}{12} + \frac{3Lt}{12} $$
 * $$ f''(b) = -\frac{8t}{12} $$

 * The negative second derivative indicates the function $$ f(b) $$ represents a concave parabola which reaches a maximum when it's slope, or first derivative, is equal to zero.

 * $$ f'(b^{(1)}) = 0 = -\frac{8tb^{(1)}}{12} + \frac{3Lt}{12}$$ → $$\frac{8tb^{(1)}}{12} = \frac{3Lt}{12} $$ → 8b(1) = 3L  → $$ b^{(1)} = \frac{3L}{8} $$

 * $$ b^{(1)} = \frac{3Lt}{12}$$ → $$ a^{(1)} = \frac{L}{2} - b^{(1)} = \frac{L}{2} - {3L}{8} = {L}{8} $$

 * $$ f(b^{(1)}) = f(\frac{3L}{8}) = \frac{1}{12}[-4t(\frac{3L}{8})^2 + 3Lt(\frac{3L}{8})] = \frac{1}{12} [\frac{9tL^2}{8} - \frac{36tL^2}{64}] = \frac{1}{12}[\frac{36tL^2}{64}] = \frac{3tL^2}{64}$$

 * Therefore

 * $$ M_{max} = 2\sigma_{allowable} \frac{3tL^2}{64}$$

 * Recalling assumption 2 ($$ M = T $$) and the equation relating the shear force to the torque ($$ \tau = \frac{T}{2abt} $$)

 * $$ \tau^{(1)}_{max} = \frac{T^{(1)}_{max}}{2a^{(1)}b^{(1)}t} = \frac{M^{(1)}_{max}}{2a^{(1)}b^{(1)}t} = \frac{2\sigma_{allowable}{\frac{3tL^2}{64}}} {2\frac{L}{8}\frac{3L}{8}t} = \sigma_{allowable}$$

 * Recall from assumption 3 ($$ \sigma_{allowable} = 2\tau_{allowable}) $$

 * $$ \tau^{(1)}_{max} = \sigma_{allowable} = 2\tau_{allowable} $$

 * $$ \tau^{(1)}_{max} > \tau_{allowable} $$

 * The maximum shear stress exceeds the allowable shear stress and therefore this solution is unacceptable.

Case Two

 * Assume the shear stress, $$ \tau $$, reaches $$ \tau_{allowable} $$ before the bending normal stress, $$ \sigma $$, reaches $$ \sigma_{allowable} $$.

 * Recall the equation determined earlier relating shear stress to torque ($$ \tau = \frac{T}{2abt} $$)

 * $$ \tau^{(2)}_{max} = \frac{T}{2abt} $$ → T(2)max = $$ 2\tau_{allowable} a^{(2)} b^{(2)} t $$

 * It's clear that maximizing the torque is equivalent to maximizing the product a(2) b(2) which recalling assumption 1 ($$ L = 2(a + b) $$) that product becomes

 * $$ \frac{L}{2}b^{(2)} + (b^{(2)})^2 = maximum$$

 * Taking the derivative

 * $$ \frac{L}{2} - 2b^{(2)} = 0 $$ → $$ 2b^{(2)} = \frac{L}{2} $$ → $$ b^{(2)} = \frac{L}{4} $$

 * $$ a^{(2)} = \frac{L}{2} - b^{(2)} = \frac{L}{2} - \frac{L}{4} = \frac{L}{4} $$

 * Therefore the torque is maximized when a(2) = b(2) = $$ \frac{L}{4}$$, therefore

 * T(2)max = $$ 2\tau_{allowable} (\frac{L}{4})^2 t = \frac{1}{8}tL^2\tau_{allowable}$$

 * Recalling assumption 2 ($$\mathbf{M} = \mathbf{T} $$)

 * $$M^{(2)}_{max} = \frac{1}{8}tL^2\tau_{allowable}$$

 * Recalling assumption 3 ($$\ \sigma_{allowable} = 2\tau_{allowable} $$)

 * $$M^{(2)}_{max} = \frac{1}{16}tL^2\sigma_{allowable}$$ → $$\sigma_{allowable} = \frac{16M^{(2)}_{max}}{tL^2}$$

 * Recall from case one

 * $$ f(b) := \frac{I}{b} = \frac{1}{12}[-4tb^2 + 3Ltb]$$ → $$ f(b^{(2)}) = \frac{1}{12}[\frac{tL}{4}[3L - L] = \frac{tL^2}{24} $$

 * Recall also from case one

 * $$ \sigma_{max} = \frac{M_{max}b}{2I} $$ → $$ \sigma^{(2)}_{max} = \frac{1}{16}tL^2\sigma_{allowable}(\frac{12}{tL^2}) = \frac{12}{16}\sigma_{allowable} $$

 * $$\sigma_{max} < \sigma_{allowable}$$

 * The maximum normal stress does not exceed the allowable normal stress and therefore this solution is acceptable. Furthermore, it proves the optimal cross section is a square such that

 * $$ \frac{b}{a} = 1 $$

title: User:Eas4200c.f08.spars.lee/Homework 2


text:
Environmental education

Major Topics
What should be covered? An overview of major topics, units, understandings, and subject matter to be covered.

(1) Earth as a planet; Thin superficial films of atmosphere and seas; temperatures and pressures that permit water to exist in all three states; ecosystem services; life-support functions, density strata,

(2) Whole-systems perspectives; biogeophysiological interactions; global equilibria; natural systems and biospheric life-support machinery; feedback loops, delayed feedbacks, regulatory mechianisms, limits, thresholds, tipping points, and unintended consequences; humans in the system

(3) Populations, population growth, human populations and demographics past, present, and future; carrying cacapacities and limiting factors, ecological release; J-curves, S-curves, logistic curves, exponential, linear, arithmetic, non-linear, IPAT

(4) Environmental mathematics (core understandings only)

(5) Conservation and biodiversity, biogeography, biomes, communities, endangered species; deforestation, overexploitation, loss of habitat. ecological footprints, industrialization, wastes, degrees of sheer physical damage to and eradication of natural systems and their services

(5) Energy flow and interactions, trophic pyramids, bioaccumulation

Key Ideas and Core Understandings
A preliminary listing of core understandings

Interactions and Feedbacks

1. Interactions - living things can affect each other (examples thereof)

2. Interactions - The non-living environment can affect living things (and examples thereof)

3. Interactions - Living things can affect the non-living environment (examples thereof)

4. Positive of self-amplifying/self-intensifying feedbacks that magnify an existing trend

5. Negative or self-correcting feedbacks that can help maintain or regulate equilibria by counteracting existing trends

Populations, population growth, carrying capacities, and limiting factors

1. Exponential growth, arithmetic progressions, J-curves, S-curves, logistic curves

2. Limiting factors (obvious varieties) - disease, supplies of food, water, resources, etc.

3. Limiting factors (less obvious, less intuitive) - Wastes (pollution) 4. Limiting factors (less obvious, less intuitive) - the extent of sheer physical damage to or eradication of functioning natural systems

5. Population calamities under "vast open-space" conditions

Ecological services 1. Production of food and oxygen,

2. Removal and sequestration of CO2

3. Soil microbes and fertilization of soils, 4. Production of rain and moderation of climate, 5. Pollination of flowering plants, 6. Control of pest populations

7. Self-maintenance, perpetuation, and repair

Online Resources
http://www.scribd.com/TheWecskaopProject (freely downloadable PowerPoint and PDF resources)

title: Environmental education


text:
User talk:M85

 Hello M85, and welcome to Wikiversity! If you need help, feel free to visit my talk page, or contact us and ask questions. After you leave a comment on a talk page, remember to sign and date; it helps everyone follow the threads of the discussion. The signature icon in the edit window makes it simple. To get started, you may

 * Take a guided tour and learn to edit.
 * Visit a (kind of) random random project.
 * Browse everything on Wikiversity, or visit a portal corresponding to your educational level: pre-school, primary, secondary, tertiary, non-formal education.
 * Find out about research activities on Wikiversity.

 * Read an introduction for teachers and find out how to write an educational resource for Wikiversity.
 * Give feedback about your initial observations
 * Discuss Wikiversity issues or ask questions at the colloquium.
 * Chat with other Wikiversitans on #wikiversity-en.

And don't forget to explore Wikiversity with the links to your left. Be bold to contribute and to experiment with the sandbox or your userpage, and see you around Wikiversity! Jtneill - Talk - c 12:56, 24 September 2008 (UTC)

 Hi , I am Percy. Nice to meet you. I love the beach, swimming, fishing, and I am currently doing some research at Wikiversity on oceanography. I am also learning to play piano. What do you like? Can I be your mascot?

Environmental education
Hi M85, I'm wondering about this edit. What was the reason you wished to blank the page? Where did the original content come from? -- Jtneill - Talk - c 13:54, 25 September 2008 (UTC)

title: User talk:M85


text:
User talk:Eml4500.f08.echo.mott/group

Hey my username is wrong on the list. It is .marshall.cwd , sorry for any inconvenience. --Charles 13:58, 24 September 2008 (UTC)

title: User talk:Eml4500.f08.echo.mott/group


text:
User:Eml4500.f08.team.Bengtson/teamHw1

Homework 1
Graphics Hardcopy

In MATLAB, there is often a need to obtain a copy of the graphic produced. The ‘Print’ option is what is used to do this. By itself this sends a high resolution copy directly to an attached printer. Adding commands such as a filename afterwards writes the current graphic to a file.

Print Eml4500

Writes current graphic to file Eml4500.

However, if the filename already exists then it will be overwritten. To attach several graphics to one file ‘-append’ should be put after the print command and before the filename that is being added to.

Print -append Eml4500

Adds current figure to eml4500 file.

Also, if one wants to get a figure besides the current one to print one just uses –fN with the print command with N being the number of the figure one wishes to write.

Print -f2 Eml4500

Prints the figure 2 to eml4500 file.

3-D Line Plots

A 3-D line plot can be with the plot3(x,y,z) command. This means that x, y, and z already have to be defined which usually is done parametrically.

T=.01:.01:20*pi; x=cos(t); y=sin(t); z=t.^3; plot3(x,y,z)

This would show a helix that compresses toward the x-y plan. To add a label to the z-axis there is a command ‘zlabel’. As well as the axis command can be used to set the scaling to prescribed limits.

3-D mesh and surface plots

There a couple commands to create mesh and surface plots. ‘Mesh(z)’ creates a three-dimensional perspective plot of the elements of matrix z. The mesh surfaced is defined by the z-coordinates above the x-y plane. Surface plots are plotted with the command ‘surf(z)’, where z is a matrix. To draw a mesh within a set of perimeter one can define a rectangle with the xx and yy vectors	 [x,y] = meshgrid(xx,yy) where [x,y] is defined through ‘z=’

xx=-3:.3:3;

yy=xx;

[x,y] = meshgrid(xx,yy);

z = exp(-x.^2 - y.^2);

mesh(z);

To impose shading on the plots and grids there is three options: shading faceted, shading interp, and shading flat. This command should be entered after the surf command. There are several predefined color profiles to choose from. To change it, use the command ‘colormap(hsv)’ which is default color profile to another selection such as ‘colormap(hot)’. The different predefined color values are hsv, hot, cool, jet, pink, copper, flag, gray, and bone.

The command ‘view’ can be used to specify from what location in coordinates the 3D object should be viewed from. It can be in either cartesian or spherical coordinates.

Sparse Matrix Calculations

MATLAB when performing matrix calculations by default assumes that any of the entries may be nonzero. However, sometimes this is not the case and to avoid lengthy calculations that become zero, there is a way to increase the efficiency so the processing power can find solutions to significantly larger problems.

The commands ‘full’ or ‘sparse’ change between the two settings, where a sparse matrix is stored as a linear array of the nonzero entries along with their row and column numbers. A full matrix records every single entry.

The sparse equivalents of eye, ones, and randn are simply done by adding sp before the command, for example ‘sprandn’. The command ‘sparse(m,n)’ creates a sparse zero matrix.

The sparse command can also create a sparse matrix by listing its nonzero components.

An example,

i = [1 2 3 4 4 4]; j = [1 2 3 1 2 3]; s = [5 6 7 8 9 10]

S= sparse(i, j, s, 4, 3);

The nonzero entries come from ‘s’ and their location by row and column number is i and j respectively. The matrix size is given by the last two numbers which makes it an m x n matrix or in this case 4x3.

Most of MATLAB operations can be used regardless of storage mode (either full or sparse). Most operation just involving a sparse matrix will continue to be in sparse mode such as S*S, S+S, inv(S), or S^n, while certain ones will be recorded in full mode such as S+F, S*F, S/F or F/S.

title: User:Eml4500.f08.team.Bengtson/teamHw1


text:
User:Eml4500.f08.team.Bengtson/teamHw2

Meeting 8-3 to 8-4
Continued from P 7-5 in Compact notation

[kij]{dj] = {fij}

6x6

More generally nxn

kijdj=fij    i=1,……,6

knxn=[kij]

nxn=global stiffness matrix

d={dj}

nx1=global displacement matrix

F=global force matrix

d5=d3(2) { node (3)

d6=d4(2)

Conceptual step of the assembly:

(Topology of K)

Meeting 11
Element 1

K(1)*d(1)=f(1)

$$\begin{bmatrix} k & -k \\ -k & k \\ \end{bmatrix} $$ $$\begin{bmatrix} d_1 \\ d_2 \\ \end{bmatrix} $$ = $$\begin{bmatrix} F_1 \\ F_2 \\ \end{bmatrix} $$

$$\begin{bmatrix} 0.5625 & 0.32476 & .... & ....\\ .... & .... & .... & ....\\ .... & ....& .... & ....\\ .... & ....& .... & ....\\ \end{bmatrix} $$ = $$\begin{bmatrix} 0\\ 0\\ 4.52\\ 6.1271\\ \end{bmatrix} $$

4x4 matrix multiplied by a 1x4 matrix

Since the top two numbers for d(1) are zero it means you can reduce the 4x4 matrix into a 2x2 matrix.

=$$\begin{bmatrix}

0.5625 & 0.3247\\ .... & ....\\

\end{bmatrix} $$ $$\begin{bmatrix} 4.52\\ 6.1271\\ \end{bmatrix} $$ =$$\begin{bmatrix} -4.4378\\ -2.5622\\ 4.4378\\ 2.5622\\ \end{bmatrix} $$ Obs Element 1 is inequal

ΣFx=F1(1) + F3(1)= 0

ΣFy=F3(1) + F4(1)= 0

P1(1) = [(F1(2))2+ (F2(1)2]1/2

Method 2: Solve for 2 Bar Truss using Statics Method

Statics Method

Other Method

title: User:Eml4500.f08.team.Bengtson/teamHw2


text: File:Exampleoverlap.JPG

title: File:Exampleoverlap.JPG


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User:Lucas

Hi and welcome! I'm Lucas, sysop on it.wiki. ;) --Lucas 17:58, 24 September 2008 (UTC)

title: User:Lucas


text:
User:Sj/thoughts

Thoughts from a recent convo with Cormaggio and mikeu, after One Web Day:

education as part of the Web
I'd love to figure out (with the whole wv community) how we can make education (and any informative social transaction) part of our notion of the Web. This was on my mind during onewebday, when I realized the immaturity of our social concept of what we can accomplish together.

If we didn't have Wikipedia, we would still be touting the web as a way to "share valuable information" and gain acces to unbiased information... as if a free channel suffices to provide valuable, unbiased, and organized knowledge. We currently have the same biases with education -- it is offered by a constellation of people, totally ad hoc, the only organized instances are proprietary and non-free, and those don't pretend to have any uniformity of style, don't recognize the value in parallel structure across courses/materials, and have an interlink ratio of a few links per page, rather than a few per sentence.

We have not recognized in any meaningful way how changing each of these elements of "knowledge about a topic online" makes wikipedia-style knowledge many orders more useful and significant than what existed before (which aside from these changes usually covered the same topics in the same depth). So it is not surprising that when people try to produce new similarly wondrous projects they talk in terms of the tools - a wiki! the internets! - and not in terms of the more subtle changes that really made the difference [say, between wikipedia as of mid-2003 and wikipedia today].

 * I tend to focus more on concrete examples, rather than a higher level view. Take a look at some of my thoughts at Observational astronomy/Planning to see the kind of projects that I think have the potential for transforming education and science on the web.  --mikeu talk 13:00, 27 September 2008 (UTC)

 * I approve of the approach of detailed planning for a specific end. Open Access to Journals is a detailed specific approach that people can rationally get behind -- higher level views tend to evoke religious rather than rational parallels.
 * And one can find a rational excuse or explanation for almost any short-term course of action by picking the right pseudo-metrics and timescales, just as one can find a mythology and vision that allows for almost any extraordinary belief structure. So it is important to address both together.  Sj
 * As an example of how we haven't stretched our minds much here -- both acawiki and p2pu have very traditional notions of what a 'journal' or 'topic' or 'course' is, how to register, how to complete and assess one's completion, and how to advertise a new resource or time-limited collaboration to the world. Sj 00:32, 7 April 2010 (UTC)
 * These are interesting thoughts. I think there are already plenty of examples of how to fuse education with the web. For example, keeping an e-Portfolio of work done is already a relatively established model for assessment: the learner documents what they've done, links to things they've written etc., and this can be checked by a teacher, employer or peers. With collaborative writing on a wiki, the process of documenting what you've done becomes that bit more complex, but certainly not impossible - and of course the transparency of a wiki's history affords such a process. I'd like to talk more about these and other issues you raise. For example, the notion of a time-limited course sits slightly uncomfortably with a wiki - what happens to it after it's done? do we become an archive of previous activities? - but experience shows me that it's a useful model to pursue... Cormaggio talk 10:18, 8 April 2010 (UTC)

title: User:Sj/thoughts


text: File:Circle b.GIF

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