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Talk:Wikipedia Ethics/Case Studies/Loud and Combative

Please explain
Please gives more details to what constitutes loud and what constitutes combative and how it relates to the centralized discussion. Dzonatas 18:21, 4 September 2008 (UTC)

 * My understanding of the meaning of the word "loud" as it relates to internet communication is that this and THIS are called "loud".
 * On Wikipedia, reasoned discourse is the preferred style of communication; aimed at improving articles. "Combative" communication on Wikipedia is, in my opinion, communication that resorts to means other than presenting evidence and reasoning. For example, simply repeating the same argument over and over.
 * An argument is not improved by saying it more times or in caps or bold. People who communicate in that style give the impression of someone who believes that it is so obvious that they are right that the other person must simply not be hearing them so they say it again LOUDER. Typically, such a person is himself not giving serious thought to what the other person is saying. These cases are often best dealt with by a third party. WAS 4.250 22:40, 4 September 2008 (UTC)

 * Examples of loud behavior by this individual can be found here. Salmon of Doubt 22:54, 4 September 2008 (UTC)

 * Salmon of Doubt, the example you gave is not helpful, and I see you didn't make any changes to the resource page to provide any further details on what was asked. What WAS wrote above could be referenced on the resource page. However, there is still details about the central discussion. What you provided above looks like another "out" attempt than an attempt to explain or add details. Dzonatas 05:46, 5 September 2008 (UTC)

 * Other than what WAS touched on earlier loud and combative, it is still pretty ambiguous what you mean, Salmon of Doubt. Do you agree with WAS about the meaning? Dzonatas 16:33, 9 September 2008 (UTC)

 * You stated "QED" in the comments of a change. Given the example above, the article is deleted, so you missed most of the conversation that took place there. You can't recount history without the article; therefore, it is not QED. Dzonatas 16:41, 9 September 2008 (UTC)


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Talk:Wikimedia Ethics/Case Studies/Biographies of Living People

I'm not trying to edit other people's presentation of the evidence, but we cannot put words written by an IP editor in Picard's mouth without her agreement that those IP edits are hers. It is both A - possibly defamatory, if she disagrees with those edits and B - possibly untrue. There's got to be a way to write about those IP edits without putting words in Picard's mouth. Salmon of Doubt 18:54, 4 September 2008 (UTC)

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


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User:Valentim

Please note: This user account is a SUL account.

The user page of this user can be found on his home wiki @ de:Benutzer:Valentim.

title: User:Valentim


text:
User:Eas4200c.f08.radsam.z

Stability

December 8th, 2008
pg 40.3 continued...

$$0=q^{(1)}+q^{(2)}+q^{(4)}=-q^{(3)}\ne o,$$

....not true or possible! since....

$$0=q^{(1)}+q^{(2)}+q^{(3)}+q^{(4)}\,$$

$$0=\sum_{e=1}^{4} q^{e}\,$$

pg 38-2:

$$q^{e}=n_{z}Q_{z}^{e}+n_{y}Q_{y}^{e}\,$$

$$n_{z}:= -(k_{y}V_{y}-k_{yz}V_{z})\,$$

$$n_{y}:=-(k_{z}V_{z}-k_{zy}V_{y})\,$$

$$\sum_{e=1}^{4} q^{e}=n_{z} \sum_{e=1}^{4} Q_{z}^{e}+n_{y} \sum_{e=1}^{4} Q_{y}^{e}\,$$

where... the sums above are equal to zero!

$$Qy=(\hat {z})=\int_{A(\hat {z})}zdA\,$$

$$Qy=\int_{A}zdA=0\,$$

 * Recalling the Mean Value Theorem, the above would simply be...

$$Qy=Zc\int_{A}dA\,$$

where...

$$Zc=0\,$$

HW #7: NACA Airfoil - "Back of envelope" verification

 * Looking at the figure above, we can see that...

$$\bar B \bar E=\bar F \bar H=\frac{1}{2}(BE+FH)\,$$

Verify magnitude of: Iy, Iz, Iyz --> (Section pg. 34-4) Angle B of N.A. $$\sigma_{xx}\,$$ @ each stringer

Read and Report

When considering beams with arbitrarily shaped cross-sections, as shown in the figure above, we place the external loads passing through the shear center/center of twist if we are avoiding torsion.

Studying the bidirectional bending in this cross-section, we obtain the longitudinal displacement as a function of x,y,z...

$$u=u_{0}(x)+z\psi_{y}(x)+y\psi_{z}(x)\,$$  (4.22a)

$$v=v_{0}(x)\,$$    (4.22b)

$$w=w_{0}(x)$$       (4.22c)

...where

$$\psi_{y}, \psi_{z}\,$$...are rotations of the cross-section about the y and z axes

The strains can be defined as...

$$\epsilon_{xx}=\frac{\partial u}{\partial x} = \frac{du_{0}}{dx}+z\frac{d\psi_{y}}{dx}+y\frac{d\psi_{z}}{dx}\,$$   (4.23a)

$$\gamma_{xy}=\frac{\partial v}{\partial x}+\frac{\partial u}{\partial y}=\frac{dv_{0}}{dx}+\psi_{z}\,$$  (4.23b)

$$\gamma_{xz}=\frac{\partial w}{\partial x}+\frac{\partial u}{\partial z}=\frac{dw_{0}}{dx}+\psi_{y}\,$$  (4.23c)

 * However recalling the assumptions... $$\gamma_{xy}=\gamma_{xz}=0\,$$...

$$\psi_{z}=-\frac{dv_{0}}{dx}\,$$

$$\psi_{y}=-\frac{dw_{0}}{dx}\,$$

...which we would substitute into equation 4.23c, and this yields...

$$\epsilon_{xx}=\frac{du_{0}}{dx}-y\frac{d^{2}v_{0}}{dx^{2}}-z\frac{d^{2}w_{0}}{dx^{2}}\,$$   (4.24)

...recalling     $$\frac{du_{0}}{dx}=0\,$$  ...if...  $$N_{x}=0\,$$...

$$\epsilon_{xx}=-y\frac{d^{2}v_{0}}{dx^{2}}-z\frac{d^{2}w_{0}}{dx^{2}}\,$$          (4.25)

 * The Bending moments about the y and z axes can be written as...

$$M_{y}=\iint_{A}z\sigma_{xx}dA=-E\iint_{A}(yz\frac{d^{2}v_{0}}{dx^{2}}+z^{2}\frac{d^{2}w_{0}}{dx^{2}})dA=-EI_{yz}\frac{d^{2}v_{0}}{dx^{2}}-EI_{y}\frac{d^{2}w_{0}}{dx^{2}}\,$$  (4.26)

$$M_{z}=\iint_{A}y\sigma_{xx}dA=-EI_{z}\frac{d^{2}v_{0}}{dx^{2}}-EI_{yz}\frac{d^{2}w_{0}}{dx^{2}}\,$$ (4.27)

where...

$$I_{y}=\iint_{A}z^{2}dA\,$$(4.28a) moment of inertia about y-axis

$$I_{z}=\iint_{A}y^{2}dA\,$$ (4.28b) moment of inertia about z-axis

$$I_{yz}=\iint_{A}yzdA\,$$ (4.28c) product of inertia

 Matrix Form:

$$\begin{Bmatrix} M_{y} \\ M_{z} \end{Bmatrix}= \begin{vmatrix} I_{y} & I_{yz} \\ I_{yz} & I_{z} \end{vmatrix} \begin{Bmatrix} -E\chi_{z} \\ -E\chi_{y} \end{Bmatrix}\,$$

$$\epsilon_{xx}=-y\chi_{y}-z\chi_{z}\,$$

$$\epsilon_{xx}=\begin{bmatrix} z & y \end{bmatrix} \begin{Bmatrix} -\chi_{z} \\ -\chi_{y} \end{Bmatrix}\,$$

$$\sigma_{xx}=\Epsilon \epsilon_{xx}=\epsilon \begin{bmatrix} z & y \end{bmatrix} \begin{Bmatrix} -\chi_{z} \\ -\chi_{y} \end{Bmatrix} \,$$

$$I^{-1}=\frac{1}{D}\begin{bmatrix} I_{z} & -I_{yz} \\ -I_{yz} & I_{y} \end{bmatrix}\,$$

where...

$$D=I_{y}I_{z}-(I_{yz})^{2}\,$$

Shear flow:

$$q=-\int_{A} \frac{d\sigma_{xx}}{dx} dA\,$$

$$\frac{d\sigma_{xx}}{dx}=\begin{bmatrix} z & y \end{bmatrix} I^{-1}\begin{Bmatrix} \frac{dM_{y}}{dx} \\ \frac{dM_{z}}{dx} \end{Bmatrix}\,$$

$$V_{y}=\frac{dM_{y}}{dx}\,$$

$$V_{z}=\frac{dM_{z}}{dx}\,$$

$$Q_{y}=\int_{A}zdA\,$$

$$Q_{z}=\int_{A}ydA\,$$

November 24th, 2008
Solving the problem: Equilibrium of each stringer

 Stringer #3

$$\sum F_{x}=0=\int_{A_{3}} [\sigma_{xx}(x+dx)-\sigma_{xx}(x)]dA_{3}\,$$

The terms... $$[\sigma_{xx}(x+dx)-\sigma_{xx}(x)]dA_{3}\,$$ is the Taylor series...

$$\frac{\partial \sigma_{xx}}{dx}dx+h.o.t\,$$

$$[-\tilde{q}_{23} -\tilde{q}_{43} +\tilde{q}_{31}]dx\,$$

 * Now, observing the contribution to shear flow by stringer 3

$$q^{3}=-\int_{A_{3}} \frac{\partial \sigma_{xx}}{dx} A_{3}\,$$

...recalling,

$$V_{y}=\frac{\partial d M_{z}}{dx}\,$$

and

$$V_{z}=\frac{\partial d M_{y}}{dx}\,$$

$$q^{3}=-(KyVy-KyzVz)Qz^{3}-(KzVz-KyzVy)Qy^{3}\,$$

$$Qz^{3}=\int_{A_{3}} ydA_{3}\,$$

$$Qy^{3}=\int_{A_{3}} zdA_{3}\,$$

 * Now for stringer #2...

$$\tilde {q}_{23}=\tilde {q}_{12} - \tilde {q}_{24} + \tilde {q}^{4}\,$$

...where the first term and second term on the right equal the shear flow in and shear flow out respectively

$$Qy^{2}=\int_{A_{2}} zdA_{2}\,$$

 * Now for stringer #4...

$$\tilde {q}_{43}=\tilde {q}_{24} - \tilde {q}_{41} + \tilde {q}^{4}\,$$

$$Qy^{4}=\int_{A_{4}} zdA_{4}\,$$

Superposition

$$q_{ij}=\tilde {q}_{ij} + q_{k}\,$$

$$q_{12}=\tilde {q}_{12} + q_{1}\,$$

...where the first term and second term to the right are the known and unknown parameters of the equation

 * Therefore...

$$q_{23}=\tilde {q}_{23} + q_{1}\,$$

$$q_{31}=\tilde {q}_{31} + q_{1}\,$$

$$q_{24}=\tilde {q}_{24} + q_{2}\,$$

$$q_{43}=\tilde {q}_{43} + q_{2} - q_{3}\,$$

$$q_{41}=\tilde {q}_{41} + q_{3}\,$$

...where we have 3 unknowns $$q_{1}, q_{2}, q_{3}\,$$

 * Thus we need 3 equations...

1) Moment Equations: Take moments of $$V_{y} V_{z}\,$$ and $$[q_{12}, ... q_{41}]\,$$ about any convenient point. (This point usually lies where lines of action of $$V_{y} V_{z}\,$$ intersect)

2)$$\theta_{1}=\theta_{2}\,$$ 3)$$\theta_{2}=\theta_{3}\,$$

NACA Airfoil

November 12th, 2008

If we were to look at a cross section of a homogeneous circular bar, and place the origin of a coordinate system in its center...

$$x^2+y^2=a^2\,$$
 * where a is the radius of the circular boundary

Now, if we were to study the lateral surface of the bar, we would observe that the stress vector (traction) would be equal to zero. This means that the traction free boundary condition states that that the change of the stress function over the lateral surface is zero...

$$\frac{d\phi}{ds}=0\,$$

or

$$\phi=constant\,$$

...This would mean that for single contour boundary-solid sections, the constant is arbitrary and thus can be zero. Hence the boundary condition can be defined on the lateral surface of the bar as...

$$\phi=0\,$$

Now that we have defined the boundary condition (stated above), we write the stress function in a form that satisfies this condition...

$$\phi = C(\frac{x^2}{a^2}+\frac{y^2}{a^2}-1)\,$$

Next we take the Prandtl stress function...

$$\frac{\partial ^2 \phi}{\partial x^2}+\frac{\partial ^2 \phi}{\partial y^2} = -2G\theta\,$$

Having obtained the compatibility equation above, we plug into it the stress function, which yields in...

$$C=-\frac{1}{2}a^2G\theta\,$$

The stress function and the equation for C above, indicate the fact that the center of the circular cross section is the center of twist.

 * Recalling the definition of torque...

$$T= 2\iint_A \phi dx dy\,$$

...we have the torque as...

$$T=2C\iint_A (\frac{x^2}{a^2} + \frac{y^2}{a^2}-1)dxdy\,$$

$$T=2C\iint_A (\frac{r^2}{a^2}-1)dA\,$$

$$T=2C(\frac{I_p}{a^2}-A)\,$$

...where

$$I_p=\iint_A r^2dA= \frac{1}{2}\pi a^4\,$$

...''where the above eq. corresponds to the polar moment of inertia and also...''

$$A=\pi a^2\,$$ since that is the cross sectional are of the circular bar.

Since...

$$a^2A=2I_p\,$$

Therefore...

$$T=-\frac{2CI_p}{a^2} = \theta GI_p\,$$

and...

$$J = I_p\,$$

 * The shear stresses are...

$$\tau_{xz}=\frac{\partial \phi}{\partial y} = 2C\frac{y}{a^2}=-G\theta y\,$$

$$\tau_{yz}=-\frac{\partial \phi}{\partial x} = -2C\frac{x}{a^2} = G\theta x\,$$

It is also worth noting that the shear stress can be expressed as...

$$\tau={Tr}{J}\,$$

 * We can also show that for bars with circular cross-sections under torsion, no warping occurs...

$$\gamma_{xz}=\frac{\sigma_{xz}}{G}=\frac{\partial w_{x}}{\partial z} - \theta_{y}\,$$

$$\gamma_{yz}=\frac{\sigma_{yz}}{G}=\frac{\partial w_x}{\partial y} + \theta_{x}\,$$

...now recalling the shear stresses derived above...

$$\sigma_{xz}=-G\theta y\,$$

$$\sigma{yz}=G\theta x\,$$

...we can see that the warping is zero...

$$w=0\,$$

Flexural Shear Flow in thin-walled sections

(Chapter 5) --> 5.1, 5.1.1, 5.1.2, 5.1.3, 5.3, 5.3.1, 5.3.2, 5.4

HW #5: Effects of M(x) on NACA airfoil

HW #6: Plate buckling, compressive in-plane load NACA airfoil

HW #7: Effects of V(x) on NACA airfoil, Plate Buckling, Shear Load.

Bidirectional Bending (Sec 4.2)
Skin and spar web do not participate in bending; only stringers

Need areas of stringers: $$A_{B} A_{E} A_{H} A_{F}\,$$

Bidirectional Bending Recipe

$$M_{y}=\int_{A} z\sigma_{xx} dA\,$$

Similarly for $$M_{z}\,$$

Moment of Inertia Tensor:

$$I_{y}=I_{yy}=I_{22}\,$$

$$I_{z}=I_{zz}=I_{33}\,$$

$$I_{yz}=I_{23}\,$$

$$I_{y}=\int_{A} z^{2} dA\,$$

$$I_{z}=\int_{A} y^{2} dA\,$$

$$I_{yz}=\int_{A} yz dA\,$$

$$\sigma_{xx}=\Epsilon \varepsilon_{xx} = \frac{I_{y}M_{z} - I_{yz}M_{y}}{I_{y}I_{z}-(I_{yz})^{2}}y + \frac{I_{z}M_{y}-I_{yz}M_{z}}{I_{y}I_{z}-I_{yz}^{2}}z\,$$

 * Recall...

 * $$\mathbf{I} = \begin{bmatrix}

I_{11} & I_{12} & I_{13} \\ I_{21} & I_{22} & I_{23} \\ I_{31} & I_{32} & I_{33} \\\end{bmatrix}$$

Note: $$D:= I_{y}-I_{z}-(I_{yz})^{2} = I_{22}-I_{33}-(I_{23})^2\,$$

...is the determinant of

 * $$\begin{bmatrix}

I_{22} & I_{23} \\ I_{32} & I_{33} \\\end{bmatrix}\,$$

$$I_{32}=I_{zy}:= \int_{A} zy dA = I_{yz}=I_{23}\,$$

Neutral Axis: where  $$\sigma_{xx}=0\,$$

$$\sigma_{xx}=m_{yy}+m_{zz}=0\,$$

--> $$z=(\frac{-m_{y}}{m_{z}}y = (\tan{\beta})y\,$$

where...$$\frac{-m_{y}}{m_{z}}y \approx \tan{\beta}=-\tan{\alpha}\,$$

Example 4.1, Pg. 124
Problem Statement

The cross section of a single-cell box beam with four stringers is shown in Figure 4.7. The Contribution of the thin sheets to bending is assumed to be negligible. Thus, only the areas of the stringers are considered in the bending analysis. The areas of the stringers are considered in the bending analysis. The areas of the stringers are...

$$A_{1}= 6x10^{-4} m^{2}\,$$ $$A_{2}= 5x10^{-4} m^{2}\,$$ $$A_{3}=A_{4}= 4x10^{-4} m^{2}\,$$

First, the centroid of the effective cross-sectional areas (i.e., those of the stringers) must be determined. Denoting the coordinates of the stringers by $$(\bar y_{j}, \bar z_{i})\,$$ with respect to the $$\bar y-\bar z$$ system, we have the coordinates of the centroid:

$$\bar y_{c}=\frac{\sum \bar y_{i}A_{i}}{\sum A_{i}} = \frac{0A_{1}+0A_{2}+0.5A_{3}+0.5A_{4}}{A_{1}+A_{2}+A_{3}+A_{4}}= \frac{4x10^{-4}}{19x10^{-4}}=0.21m\,$$

$$\bar z_{c}= \frac{\sum \bar z_{i}A_{i}}{\sum A_{i}}=\frac{0.4A_{1}+0A_{2}+0A_{3}+0.3A_{4}}{A_{1}+A_{2}+A_{3}+A_{4}}=\frac{3.6}{1.9}=0.19m$$

Thus, the location of the centroid is (0.21, 0.19) in the $$\bar y - \bar z\,$$ system.

This cross section consisting of four stringers is not symmetric with respect to either the y- or the z-axis. Hence, the general bending equations must be used. The moments of inertia of the effective cross sectional area of the box beam with respect to the coordinate system y-z are calculated according to (4.28). Denoting the coordinates of each stringer by $$(y_{i},z_{i})$$ with respect to the y-z system, we have

$$I_{y} = \sum A_{i}Z_{i}^{2} = A_{1}(0.4-0.19)^2 + (A_{2}+A_{3})(0.19)^{2}+A_{4}(0.3-0.19)^{2}=0.63x10^{-4}m^{4}\,$$

$$I_{z}=\sum A_{i}y_{i}^{2}=(A_{1}+A_{2})(0.21)^{2}+(A_{3}+A_{4})(0.29)^{2}=1.16x10^{-4}m^{4}\,$$

$$I_{yz}=\sum A_{i}y_{i}z_{i}=A_{1}(-0.21)(0.21)+A_{2}(-0.21)(-0.19)+A_{3}(0.29)(-0.19)+A_{4}(0.29)(0.11)=-0.15x10^{-4}m^{4}\,$$

Consider the loading $$M_{z}=0\,$$ and $$M_{y}\ne 0\,$$ The neutral plane is given by...

$$\tan{\alpha} = -\frac{I_{yz}M_{y}}{I_{z}M_{y}} = \frac{0.15x10^{-4}}{1.16x10^{-4}}=0.13\,$$

which yields...

$$\alpha = 7^\circ$$

measured clockwise from the y-axis.

The Structural Beam
!Bending Member (Beam) -Contribution from Chapter 1.2.3 by Radsam.Z

The beam is an elemental structure used in all walks of life, from civil engineering to aerospace engineering. Beams provide structural support by providing resistance to bending moments. "A beam can also be used as an axial member carrying longitudinal tension and compression."

The bending moment is mathematically described to beam deflection as...

$$M=-EI\frac{d^2w}{dx^2}$$

where... EI= Bending Stifness of the beam I= Moment of Inertia

The Beam in Aerospace Structures
An example of a beam used in the aerospace industry is that in some airplane wings. This type of beam is called a cantilever beam, which is only supported in one end, carries both a bending moment and a transverse shear stress. However for a beam of large span/depth ratio, as in the case in aircraft wings, the bending moment is much greater than the shear stress.

The maximum bending moment at the root... $$\sigma=\frac{M_{max}(\frac{h}{2})}{I}$$

The maximum transverse shear stress distribution at the neutral plane... $$\tau_{max}=\frac{3}{2}\frac{V}{bh}$$

If we take the ratio of both the maximum bending moment and shear stress... $$\frac{\sigma_{max}}{\tau_{max}}=\frac{4L}{h}$$

From this it is clear that the bending moment is the ruling factor in aircraft wings. So in order to address this issue aircraft engineers focus in the improvement of airfoils depending on the type of aircraft. For instance high performance military jet-aircraft, that undergo high-loading forces would definitely need stronger wings (cantilever beams) than say a cargo aircraft. In order to make an aircraft more "resistant" to these high bending forces, engineers design these type of aircraft with a low aspect ratio ...

$$AR = {b^2 \over S}$$                    where... b = wingspan S = planform area

Problem Explanation and Proof of Shear Stress

 * {| class="toccolours collapsible collapsed" width="100%" style="text-align:left"

!Bending Member (Beam) -Contribution from Chapter 1.2.3 by Radsam.Z The closed-walled beam under scrutiny is one of negligible thickness, thus one can assume that the shear stress distribution is of a uniform nature...

Therefore adding respectively the torque on each side of the box...

$$T= T_{AB}+T_{BC}+T{CD}+T{DA}$$

...where torque equals the lever arm times the shear stress by the wall thickness... $$T_{AB}=\frac{b}{2}(va) = \frac{1}{2}\tau(abt)$$

$$T_{BC}=\frac{a}{2}(vb) = \frac{1}{2}\tau(abt)$$

$$T_{CD}=\frac{b}{2}(va) = \frac{1}{2}\tau(abt)$$

$$T_{DA}=\frac{a}{2}(vb) = \frac{1}{2}\tau(abt)$$

and recalling...

$$T= T_{AB}+T_{BC}+T{CD}+T{DA}$$

$$T=2\tau(abt)$$

or

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

 * }

Problem 1.1 - Case#1

 * {| class="toccolours collapsible collapsed" width="100%" style="text-align:left"

!Solution to Case 1 by Radsam.Z If we assume that the maximum bending stress is the allowable bending stress then we have...

$$\sigma_{max}=\sigma_{allowable}$$

By recalling the bending stress formula...

$$\sigma=\frac{Md}{I}$$

 * sigma=bending stress
 * M= moment at the neutral axis
 * d=distance measured perpendicular to the neutral axis
 * I=the moment of inertia

Now by observing the rectangular beam we can determine that the bending stress would equal...

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

or by our assumption of maximum bending stress being equal to the allowable stress

$$M=\frac{\sigma I}{z}$$ where $$z=\frac{b}{2}$$

After some arithmetic manipulation and solving for bending moment...

$$M=\frac{2I\sigma_{max}}{b} = \frac{2I\sigma_{allowable}}{b}$$

Therefore as we can see from the above equation if we wish to maximize M, the only term of the equation that can be optimized is the ratio of the inertia over b

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

recall : the ratio is a function of a and b...since the perimeter length $$L=2(a+b)=constant$$

Following the parallel axis theorem we find... "The parallel axes rule applies to the second moment of area (area moment of inertia);
 * $$I_z = I_x + Ad^2.\,$$

where:

Iz is the area moment of inertia through the parallel axis,

Ix is the area moment of inertia through the centre of mass of the area,

A is the surface of the area, and

d is the distance from the new axis z to the centre of gravity of the area."

...Now if we apply this to our rectangular beam as follows...

$$I=\sum_{1}^4 [\frac{b_{i}(h_{i})^3}{12} + A_{i}(d_{i})^2]$$

$$=2\frac{(tb)^3}{12}+2 [\frac{at^3}{12}+(at)(\frac{b}{2})^2]$$ $$=\frac{a}{12}[t^3+t(\frac{12}{4})b^2]$$ $$=\frac{at}{12}[t^2+3b^2] =3\frac{ab^2t}{12}$$

considering t<<b   and   t^2<<b^2    and   t^2<<3b^2

$$I= 2\frac{tb^3}{12}+\frac{ab^2t}{2} = \frac{b^2t}{2}(\frac{b}{3}+a) = \frac{tb^2}{6}(3a+b)$$

$$\frac{I}{b}=\frac{tb}{6}(3a+b)$$

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

$$=\frac{tb(3L-4b)}{12} = \beta_{0}+\beta_{1}b'+\beta_{2}b^2$$ $$\beta_{0}=0$$ $$\beta_{1}=3\frac{Lt}{12}$$ $$\beta_{2}=\frac{-4}{12}t=-\frac{t}{3}$$

and

$$\frac{d^2f}{db^2}(b)=2\beta_{2}=-\frac{2t}{3}<0$$ (this tells us that the second derivative is negative and if we recall from Calculus this means that our graph will be concave down and our point of interest will be a maximum!)

...thus finding the maximum by evaluating the graph

$$f(b)=0$$ and $$b=0$$ and $$b=\frac{3L}{4}$$ (the endpoints of the circle)

and as we see in the in the graph the maximum point is $$b=3\frac{L}{8}$$

$$\frac{df}{db}(b)=\beta_{1}+2\beta_{2}b = aprox = 0$$

therefore the solution for case #1 is...

solving for b in the above equation

$$b=-\frac{\beta_{1}}{2\beta_{2}} = \frac{3L}{8}$$

and if we recall the definition

$$L=2(a+b)$$

thus, we obtain...

$$a^(1) = \frac{L}{2}-b^(1)=\frac{L}{8}$$

...and we can obtain a ratio of a to b...

$$\frac{b^1}{a^1} = 3$$

and recalling that in order to maximize the Torque we needed to maximize the ratio...

$$(\frac{I}{b})_{max}=\frac{I^1}{b^1}$$

$$=\frac{tb}{6} (3a+b) = \frac{tb}{6} (3a + 3a) = \frac{tb}{6} (6a)$$

which reduces to...

$$= abt = \frac{btL}{8} = \frac{3tL^2}{64}$$

...and finally replacing this ratio into the maximum torque equation...

$$M^1_{max}=(2\sigma_{allowable})\frac{I^1}{b^1}$$

...yields the final result...

$$M^1_{max}=3\frac{tL^2}{32} \sigma_{allowable}$$

 * Which also means --->

$$T_{max}= 3\frac{tL^2}{32} \sigma_{allowable}$$

 * $$\tau_{max}=\frac{T_{max}}{2\frac{L}{8}\frac{3L}{8}t}$$

 * $$\sigma_{allowable} = \frac{M_{max}}{2\frac{L}{8}\frac{3L}{8}t}$$

$$\tau^1_{max} = \sigma_{allowable} = 2\tau_{allowable} > \tau_{allowable}$$

$$\tau^1_{max} > \tau_{allowable}$$ is NOT acceptable

This is the conclusion of Case #1

October 10th, 2008 Lecture
{| class="toccolours collapsible collapsed" style="width:100%" ! Lecture from Friday - October 10th, 2008

Recalling...

Torsion : $$T = GJ\theta\,$$

[ http://en.wikipedia.org/wiki/Torsion_(mechanics)]
 * T is the torque (N·m or ft·lbf)
 * G is the shear modulus or more commonly the modulus of rigidity and is usually given in gigapascals (GPa), lbf/in2 (psi), or lbf/ft2
 * J is the torsion constant for the section . It is identical to the polar moment of inertia for a round shaft or concentric tube only. For other shapes J must be determined by other means. For solid shafts the membrane analogy is useful, and for thin walled tubes of arbitrary shape the shear flow approximation is fairly good, if the section is not re-entrant. For thick walled tubes of arbitrary shape there is no simple solution, and FEA may be the best method.
 * $$\theta\,$$ is the angle of twist in radians.

Once $$\theta\,$$ is found as a function of T, use...

$$\theta = \frac{T}{GJ}\,$$

or

$$J=\frac{T}{G\theta\,}$$

...to find J

HW #4:

 * 3-cell NACA 2415 airfoil
 * 2 partition walls
 * 1st wall at quarter chord from leading edge
 * 2nd wall at three quarter chord from leading edge

3 unknowns... $$q_{1}, q_{2}, q_{3}\,$$:

 * 1) $$T=2\sum_{i=1}^3 q_{i} \bar{A}\,$$
 * 2) $$\theta_{1}=\theta_{2}\,$$
 * 3) $$\theta_{2}=\theta_{3}\,$$

...to find J

Finding J...

Note: need thickness t, but G cancels out...

 * Now Theory derivation

$$T=GJ\theta\,$$ (done)

$$T=2q\bar{A}$$  (done)

$$\theta=\frac{1}{2G\bar{A}}\oint \frac{q}{t} ds\,$$

Contribution by "Eas4200c.f08.radsam.z 23:45, 19 October 2008 (UTC)"

Uniform bar w/non-circular cross section subject twist

Displacement $$\underline{PP'}$$ due to $$\alpha\,$$

$$\frac{PP'}{O\underline{P}} = \alpha\,$$ (for alpha small)

Projection Displacement $$\underline{PP'}$$ on the direction perpendicular to $$O\underline{P'}:$$

$$\underline{PP''}=\underline{PP'} cos{\alpha}\,$$

$$\underline{PP''}= (O \underline{P} tan{\alpha}) cos{\alpha}\,$$

$$=(O\underline{P} cos{\alpha}) tan{\alpha}$$

''where... $$O\underline{P} cos{\alpha} = O\underline{P}\,$$

Recall:

$$O\underline{P} = r \,$$ (radial coord)

$$O\underline{P''} = \rho \,$$

$$PP''= (r cos{d}) tan{\alpha}\,$$

 * where: PP is displacement of $$\underline{P}$$ in direction tangent to lateral surface of bar

 * $$r( cos{d})\,$$ is approximately $$\rho\,$$

 * $$tan{\alpha}\,$$ is approximately $$\alpha\,$$

Strain:

$$\gamma=\frac{\underline{PP''}}{dx} = \frac{\rho \alpha}{dx} = \rho \theta\,$$

with... $$\theta = \frac{\alpha}{dx}$$ rate of twist angle (alpha very small!)

title: User:Eas4200c.f08.radsam.z


text:
Wikiversity:Maintenance/header

Welcome to the Wikiversity Maintenance Hub!

Maintenance is one of the most important things that anyone can do at Wikiversity, along with teaching, learning and researching. Wikiversity constantly needs people to maintain the site, and anyone can get involved in maintaining Wikiversity. You don't have to ask - you can just pick some open tasks and get on with the job! On the page below you can find plenty of information and links to start you off with your maintenance "career" here. When you become better at maintenance tasks, you can start to identify new tasks that need doing and add them to the lists and categories.

If you stay around Wikiversity for long, and especially if you take part in maintenance, you'll soon come across the term custodian, which is what we call an "admin" or someone with "sysop privileges". Custodians have access to a few extra options on the MediaWiki interface, which enable them to do some maintenance operations faster, and do other maintenance operations which might have more radical effects on Wikiversity. For example, custodians can delete pages and block disruptive users. These operations are things which it is generally felt that not everyone should have access to. If you find a job which needs a custodian, then feel welcome to ask one!

Sometimes people decide it might be a nice idea to become a "custodian" themselves. If you want to: here's a quick how-to. First, realise that custodians (or admins) do a lot of pretty unpleasant boring jobs and end up sacrificing a lot of their family/holiday time. It's hardly a prestigious job. Secondly, before you even think of applying, get stuck into a lot of the maintenance jobs below which anyone can do. This is a good way to show that you are suitable material for doing chores! But remember: if you enjoy making Wikiversity a better place by maintaining it, you don't have to be a custodian. Quite the opposite: ordinary users are especially welcome at the maintenance hub, and we hope the majority of people who come here will be ordinary users who just enjoy taking a few minutes to make Wikiversity a better place for everyone.

Oh - and finally, an especially big thank you to everyone who participates at the maintenance hub:

Thank you!

title: Wikiversity:Maintenance/header


text:
User:Eml4500.f08.bottle.barnes

=Homework 1=

user:Eml4500.f08.bottle.barnes/HW1

=Homework 2=

user:Eml4500.f08.bottle.barnes/HW2

=Homework 3=

user:Eml4500.f08.bottle.barnes/HW3

=Homework 4=

user:Eml4500.f08.bottle.barnes/HW4

=Homework 5=

user:Eml4500.f08.bottle.barnes/HW5

=Homework 6=

user:Eml4500.f08.bottle.barnes/HW6

=Homework 7=

user:Eml4500.f08.bottle.barnes/HW7

title: User:Eml4500.f08.bottle.barnes


text:
User:Eas4200c.f08.carbon.orear

EAS4200C: Aerospace Structures 1

Honor Code statement:

Each member of Team Carbon will respect the University Honor Code and to indicate that they contributed to the group work for the week. "On my honor, I certify that I have neither given nor received any unauthorized aid on this assignment."

Jeffrey O'Rear

Jeffrey Wright

Abby Booth

Beau Guidry

Aaron J Clausen

Brian Taylor

=Course Information=

Course Website: www.mae.ufl.edu/~vql → "teaching" → "my course website" → "EAS4200C Aerospace Structures" EAS4200c Course website

Password: fall08.wiki

Office: 135 NEB - MWF 9th (office hours)

=Course Content=

The Finite Element Method (FEM) makes solving partial differential equations (PDEs) convenient. This is integral to the study of Aerospace Structures, or its structural components.

The emphasis of the course will be to understand structural mechanics, formulate problems, judge solution correctness, and avoid ad-hoc structural analysis methods.

The plan of the course is to maintain confidentiality while using large-scale peer-to-peer domains including Wikiversity and MIT's OpenCourseWare in addition to the textbook. The course will examine the method of work instead of other approaches such as e-learning and the old approach to this class (10% HW and 30% x 3 for each exam). This format allows students to be introduced to MediaWiki and stimulate collaboration with other students, teams, the professor, and the class as a whole.

There are several relevant time zones important to us (UTC, EDT, and EST). HW will be turned in according to the UTC time to maintain consistency with the Wikipedia time stamp format.

HW shortcuts should be created by attaching the URL from the archived version by going to "History" → click on the date to open archived version → copy this address to submit.

--

It is important that during this course we learn how and why some things work and others do not. It's also important to expand our ability to articulate problems, solve them and judge that our answer is reasonable. Finite Element Analysis (FEA) of Aircraft Structures is important to study for safety, longevity, and efficiency. An example of insufficient FEA in engineering is the recent Minnesota bridge collapse.

=Discussion= I think we could be considered very close to the top three reports. We could expand our incorporation of textual support, related details, and textbook supplementary information. Overall, in viewing class reports that were posted, I think we did fairly well. Good job on the advanced work of Problem 1.1! Eas4200c.f08.carbon.orear

For help with wiki math formatting, http://en.wikipedia.org/wiki/Wikipedia:Math Eas4200c.f08.carbon.clausen 14:22, 26 September 2008 (UTC)

=Homework=

 * Week 1 Notes
 * Problem 1.1
 * Homework 2 (current version)
 * Homework 3 (current version)
 * Homework 4 (current version)
 * Homework 5 (current version)
 * Homework 6 (current version)
 * Homework 1 (current version) Please submit this link (archived version) with HW 2 (send 2 links total)
 * Homework 7 (current version)

title: User:Eas4200c.f08.carbon.orear


text:
Spanish 2

Welcome to Spanish 2! You've already begun to understand, speak, read and write in Spanish. You've also learned about Spanish-speaking countries and their cultures. In Spanish 2 you'll be using and building what you learned in your first year of Spanish.

 * Review
 * Chapter 1 (Classroom Events)
 * Including cultural insight on Mexico City
 * Chapter 2 (Free Time)
 * Including cultural insight on comparison of school in the United States and Hispanophone countries
 * Chapter 3 (Daily Activities)
 * Including cultural insight on ponchos
 * Chapter 4 (Fashion)
 * Including cultural insight on parties
 * Chapter 5 (Errands)
 * Including cultural insight on open-air markets
 * Chapter 6 (On the Road)
 * Including cultural insight on neighborhoods
 * Chapter 7 (Childhood)
 * Including cultural insight on childhood songs
 * Chapter 8 (Celebrations)
 * Including cultural insight on Día de los Reyes Magos
 * Chapter 9 (Emergencies)
 * Including cultural insight on legends
 * Chapter 10 (Accidents)
 * Including cultural insight on Social Security and healthcare
 * Chapter 11 (Television)
 * Including cultural insight on television guides
 * Chapter 12 (Movies)
 * Including cultural insight on foreign language movies
 * Chapter 13 (Cooking)
 * Including cultural insight on tortillas
 * Chapter 14 (Picnics)
 * Including cultural insight on outdoor eating
 * Chapter 15 (Planning a trip)
 * Including cultural insight on travel documents
 * Chapter 16 (Traveling)
 * Coming soon
 * Addendum (Verbs)
 * Including tables of regular and irregular verbs.

title: Spanish 2


text:
User:CraigWilliam/CSoP/Psychology

Welcome to the Division of General Psychology! A division of the CraigWilliam School of Psychology.

Division News and Announcements
2008.09.04 - Division of General Psychology founded!

Learning Projects (Courses)

 * Introduction to Psychology
 * This Learning Project introduces students to the study of psychology as a science. The course will cover the basic research methods of psychological science as well as give students a taste of the various topics researched within psychology.
 * Lessons:
 * Before Psychology
 * Psychology as a Science
 * BioPsychoSocial
 * Development across the Life Span
 * Sensation and Perception

 * History of Psychology
 * This Learning Project covers the important figures and time periods that have shaped the study of psychology as it stands today.

More Learning Projects are hosted within individual departments.

Departments

 * Department of Comparative Psychology

 * Department of Experimental Psychology

 * Department of Multicultural and Diversity Psychology

 * Department of Positive Psychology

 * Department of Quantitative, Methodological, and Mathematical Psychology

title: User:CraigWilliam/CSoP/Psychology


text:
User:Eas4200c.f08.aero6.loper

--Eas4200c.f08.aero6.loper

$$W_{wg} = 0.0017W_{zf}n_{ult}^{0.55}t_{r,max}^{-0.3}\left(\frac{b}{cos \Lambda_{c/2}}\right)^{1.05}\left(1+\sqrt{\frac{6.25cos \Lambda_{c/2}}{b}}\right)\left(\frac{W_{zf}}{S}\right)^{-0.3}$$ $$W_{f} = 0.021S_{g}^{1.2}\sqrt{V_{D,E} \frac{l_{t}}{d}}$$ $$W_{mg} = 40+0.16W_{to}^{3/4}+0.019W_{to}+1.5\times10^{-5}W_{to}^{3/2}$$ $$W_{ng} = 20+0.10W_{to}^{3/4}+2\times10^{-6}W_{to}^{3/2}$$ $$W_{h} = S_{h}k_{h}\left[2+4.15erf\left(\frac{S_{h}^{0.2}V_{D,E}}{10^{3}\sqrt{cos \Lambda_{h}}}-0.65\right)\right]$$ $$W_{v} = S_{v}k_{v}\left[2+4.15erf\left(\frac{S_{v}^{0.2}V_{D,E}}{10^{3}\sqrt{cos \Lambda_{v}}}-0.65\right)\right]$$ $$W_{pg} = 1.42N_{e}W_{e}\!$$

title: User:Eas4200c.f08.aero6.loper


text:
User:CraigWilliam/CSoP/Psychology/Introduction to psychology

Welcome to the learning project Introduction to Psychology!

The following is a suggested list of headings for a learning project. For more information, please read the directions. Please organise the page as you see fit.

Learning project summary

 * Project code:
 * Suggested Prerequisites:
 * Time investment:
 * Assessment suggestions:
 * Portal: Portal:...(List main portal/s here)
 * School: School:... (List main school/s here)
 * Department: Topic:...
 * Stream:
 * Level:
 * Department: Topic:...
 * Stream:
 * Level:

Content summary
Describe this learning project in a sentence or two.

Goals
In this learning project we aim to...

Learning materials
Add learning materials here. See also the box below.

Readings and other resources
Each project/lesson/activity may have a suggested reading selection. For example:
 *  ...
 *  ...

Lessons

 * Lesson 1: /.../
 * Lesson 2: /.../

Activities

 * Activity 1:
 * Activity 2:

Tests and quizzes

 * Quiz 1:
 * Quiz 2:
 * Test 1:

Subpages
Subpages can be created - using the syntax '/concepts/' (for concepts involved in this learning project & without the quotes).

Links to subpages can be automatically shown using

Active participants
Active participants in this Learning Group


text:
User talk:Eas4200c.fo8.aero.oyama

 Hello Eas4200c.fo8.aero.oyama, 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! --JWSchmidt 03:22, 5 September 2008 (UTC)

title: User talk:Eas4200c.fo8.aero.oyama


text:
User talk:EML4500.f08.Wiki.Kehoe

 Hello EML4500.f08.Wiki.Kehoe, 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! --JWSchmidt 03:22, 5 September 2008 (UTC)

title: User talk:EML4500.f08.Wiki.Kehoe


text:
User talk:Eml4500.f08.wiki.hood

 Hello Eml4500.f08.wiki.hood, 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! --JWSchmidt 03:23, 5 September 2008 (UTC)

a question for you
Thanks for uploading Image:3dmeshsurface4.jpg to Wikiversity. Could you take the time to provide some information about the source of the image? Did you make the image? Do you have any preference for how to license the image? is that you assumed it would be available under the GFDL. --JWSchmidt 04:32, 9 September 2008 (UTC)

title: User talk:Eml4500.f08.wiki.hood


text:
User talk:Popx~enwikiversity

 Hello Popx, 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! --JWSchmidt 03:24, 5 September 2008 (UTC)

Your account will be renamed
Hello,

The developer team at Wikimedia is making some changes to how accounts work, as part of our on-going efforts to provide new and better tools for our users like cross-wiki notifications. These changes will mean you have the same account name everywhere. This will let us give you new features that will help you edit and discuss better, and allow more flexible user permissions for tools. One of the side-effects of this is that user accounts will now have to be unique across all 900 Wikimedia wikis. See the announcement for more information.

Unfortunately, your account clashes with another account also called Popx. To make sure that both of you can use all Wikimedia projects in future, we have reserved the name Popx~enwikiversity that only you will have. If you like it, you don't have to do anything. If you do not like it, you can pick out a different name.

Your account will still work as before, and you will be credited for all your edits made so far, but you will have to use the new account name when you log in.

Sorry for the inconvenience.

Yours, Keegan Peterzell Community Liaison, Wikimedia Foundation 23:41, 17 March 2015 (UTC)

Renamed
 This account has been renamed as part of single-user login finalisation. If you own this account you can |log in using your previous username and password for more information. If you do not like this account's new name, you can choose your own using this form after logging in: . -- Keegan (WMF) (talk) 06:18, 19 April 2015 (UTC)

title: User talk:Popx~enwikiversity


text:
User talk:Eml4500.f08.FEABBQ.koby

 Hello Eml4500.f08.FEABBQ.koby, 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! --JWSchmidt 03:24, 5 September 2008 (UTC)

WOW!! What a great page!

title: User talk:Eml4500.f08.FEABBQ.koby


text:
User talk:Eml4500.f08.FEABBQ.vitt

 Hello Eml4500.f08.FEABBQ.vitt, 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! --JWSchmidt 03:25, 5 September 2008 (UTC)

a question for you
Hi! I see you uploaded Image:Florida Gators logo.svg to Wikiversity. What is the source of the image? It looks like it might be subject to copyright restrictions. Please take a look at Uploading files. --JWSchmidt 05:01, 9 September 2008 (UTC)

title: User talk:Eml4500.f08.FEABBQ.vitt


text:
User:Alex Esp

 * My user page in catalan

title: User:Alex Esp


text:
Template talk:Delete

Updating this template
I've made a few changes here. Mostly this is to accommodate for the problem that most wiki user's don't know how to use template parameters and often don't sign. There are now invitations to state reasons and discuss issues on the talk page of the resource. The possibility of replacement with the DR tag (deletion by consensus) is now also more helpfully indicated. --McCormack 06:40, 5 September 2008 (UTC)
 * I was so busy adding the TALKPAGENAME magic word 5 days ago that I forgot that the previous editor had also deleted the policy links which allow editors to find out when to use/not use this template. The policy links were an essential part of this template. --McCormack 14:09, 10 September 2008 (UTC)

title: Template talk:Delete


text: Template:User knowledge-4

title: Template:User knowledge-4


text: Template:User blank knowledge-4

title: Template:User blank knowledge-4


text:
Wikiversity talk:Student union

A discussion on the content of the Student Union page
Ready made to discuss the content of the page, and the content of the page alone. What would you like to discuss? Salmon of Doubt 20:50, 5 September 2008 (UTC)

Here, since you won't discuss, I'll start it for you. This page is designed to welcome new users who are students to this project. Your proposed changes are not welcoming. They are confusing and divisive. This page should be an overview. If you'd like to link to your discussion of deletionism on this page, I think that's a great idea. Salmon of Doubt 20:56, 5 September 2008 (UTC)

 * I think Salmon of Doubt could have made a more helpful change then to completely revert and blank the content. Link to the deletionism page. Dzonatas 21:04, 5 September 2008 (UTC)

 * "since you won't discuss" <-- You gave me all of 5 minutes to get here? --JWSchmidt 21:05, 5 September 2008 (UTC)

 * You reverted again, even though I specifically told you I was prepared to discuss. However, please, let's discuss the content of the Student Union page, not other irrelevent issues. Thanks. Salmon of Doubt 21:08, 5 September 2008 (UTC)
 * Saying "I'm prepared to discuss" in an edit summary is not the same as discussing. I did not revert the page, I have been developing the page content. You are the one who has repeatedly reverted the page in violation of policy. --JWSchmidt 21:36, 5 September 2008 (UTC)

 * Let's compare my proposed version of the page to the proposed alternatives. McCormack proposed deleting the page and deleting links to the page. Jade Knight proposed turning the page into a redirect to a page that does not mention students at all. Your preferred version is essentially an attempt to remove a useful learning exercise from the page, an exercise I created in response to a call for the page to be developed. In my view, all of these proposed alternatives are inferior to the learning exercise option that I favor. "not welcoming" <-- feel free to put a welcome message on the page. "confusing" <-- feel free to edit for clarity. "divisive" <-- now why should that be the case? Please explain how it is "divisive" to help students learn about what is going on at Wikiversity? "This page should be an overview" <-- Feel free to add an "overview". You can do so without removing the learning exercise about how some editors are working to destroy the page and attempting to prevent Wikiversity from providing a link to the page from the Main Page and trying to turn the page into a redirect to another page that does not even mention students. That is useful information that new Wikiversity participants should be aware of, and the learning exercise introduces students to active learning at Wikiversity. --JWSchmidt 21:31, 5 September 2008 (UTC)

New Student Portal
Okay, I see the the process of creating a new Student Union here as following three steps: 1. Brainstorm for ideas, set goals, and get a general sense for what we want to see here. 2. Plan. How will we implement the goals and concepts we want to have here? 3. Develop/Create. Put those plans into action.

So, step 1. Brainstorm. What kind of content do we think is going to be important here at the hub for all learning activity? My thoughts: The Jade Knight 21:44, 5 September 2008 (UTC)
 * 1) A prominent link to the java Wikiversity IRC chat applet.
 * 2) A link to the various content guides (guided tours)
 * 3) A prominent link to a page explaining how to find everything, emphasizing the powerful (though still somewhat disorganized ATM) Browse feature.
 * 4) A link to WV policies.
 * 5) Messages telling students that:
 * 6) Wikiversity is a place for them to explore their learning goals and personal interests
 * 7) Wikiversity is a place for them to collaborate and guide the creation of learning resources.
 * 8) Students have to click the edit button to participate in some projects; we all learn by editing.
 * 9) An explanation on how to edit (IMO, this would be best as a prominent link to the appropriate tour or page - JK)
 * 10) What else?

 * The student portal should tell students that Wikiversity is a place for them to explore their learning goals and personal interests. The student portal should tell students that Wikiversity is a place for them to collaborate and guide the creation of learning resources. The student portal should tell students that they have to click the edit button and participate in "learn by doing" projects, that at Wikiversity we all learn by editing. The student portal should help new participants get started on learning how to edit. --JWSchmidt 22:48, 5 September 2008 (UTC)

 * I've incorporated your suggestions into my list. Tell me if I've misinterpreted anything.  The Jade Knight 02:15, 6 September 2008 (UTC)
 * Looks good. --JWSchmidt 03:26, 6 September 2008 (UTC)
 * I also think we want to reduce clutter as much as possible; keep things simple while still including everything we think new students should need. The Jade Knight 06:29, 6 September 2008 (UTC)

Portal:Student Union
This Student union page should now be redirect to Portal:Student Union which I've just fully done - I've found out on the help section, instructions on how to make a portal so I've thought about improving the current one - anyone who wants to work on the Student Union section could redirect it to the new Portal. DarkMage 19:51, 10 September 2008 (UTC)
 * Why Portal: over Wikiversity:? The Jade Knight 03:23, 11 September 2008 (UTC)
 * The standard coding doesn't allow it to be renamed to the Wikiversity name - I've tried it many times, even within my own user-subpage but it created it as a Portal which implies that it can only be as a Portal - truth be known I don't know how to correct it. It also created these Portal:Dark Mage/Wikiversity-Updates/Student Union/Page2/Tasks and other subpages within the Portal section but not in my subpage as I was intended to do so - I'm sort of new to that type of configuration in the portal section, so I don't know everything - it maybe possible to rename it to Student union or to Portal:Learners like McCormack suggested on my talkpage though with those so many redirect links which was accidently created I prefer not to move it, as other users may start to think that I'm trying to make a mess of things, which has happened before when I used to be known as Terra on this site. DarkMage  17:24, 11 September 2008 (UTC)
 * Although I've stated in the above section that it wasn't possible to rename it - I've just transfered a lot of the coding which was being used and placed it as a subpage, it may now be possible to rename it and replace the current student union page though I wouldn't mind approval first. DarkMage  18:02, 11 September 2008 (UTC)

Student Union - Update
I've managed to rename the Portal:Student Union to Student Union and left a redirect link from the old Student union page - however there are some issues with the links, for some reason it keeps saying that the page has been redirect from Portal:Student Union and have tried to fix the problem but can't for some reason could someone have a look at the links, if I'm right all of the pages should have been moved correctly. DarkMage 19:03, 11 September 2008 (UTC)

title: Wikiversity talk:Student union


text:
School talk:History/Archive 1

added dept
I added the department I'm most interested in. Someone please tell me if I'm out to lunch, I found the namespaces stuff confusing.

Unnr 16:39, 31 August 2006 (UTC)

In Memoriam: September 11, 2001
The "In Memoriam: September 11, 2001" might be the starting point for some Wikiversity "living history" projects. --JWSchmidt 19:01, 16 September 2006 (UTC)

What kind of project are you thinking about in this area? Do keep in mind that wiki is more than just U.S. perspective..so something titled as you have suggested might turn people away from participating in the project. As a more historically related title I would suggest something like: "Psychological Effects of the WTC attack (9/11) on U.S. Citizens" or "International Response to the WTC Attack". The main goal in history is to evaluate an event and how that effects everything around it, but in terms of wiki, the title originally suggested sounds more like a wikipedia article or even bordering on propaganda than a wikiversity project that is oriented to 'explore' a subject. --Kfitton 14:40, 10 October 2006 (UTC)
 * I think you misunderstand JWSchmidt; he wasn't suggesting that the September 11 wiki's title be used as a course in History, but rather that many of the materials there could be useful in History courses. The Jade Knight 01:57, 12 October 2006 (UTC)

War Historian for Hire
Hi there, I'd look into assisting on topics in War History. I already have several courses planned, but I intend to make them fit the course templates I've made. They should be self regulating and create feedback loops of continuous improvement if they are followed. I understand some courses are out in Wikibooks. I don't know how those courses are run, but I'd like to know more about this school's philosophy on courses and what the current consensus is on "teaching" (as it seems to be practiced in certain courses here - complete with marked projects) and "group learning."--Dnjkirk 16:21, 16 October 2006 (UTC)
 * The one thing I think we want to avoid are self-teaching courses. These are the sort which are found in Wikibooks and belong in Wikibooks.  All courses, projects, etc., here should require (or at least expect) collaboration and/or "teacher" feedback.  If you want to make a self-teaching course, you're welcome to, but it would probably belong in Wikibooks, and then linked to from here.  Other than that, really, you can come up with anything you think might be effective.  We've been encouraged to experiment.  The Jade Knight 21:11, 16 October 2006 (UTC)
 * One would expect that books be in Wikibooks and courses be in Wikiversity. Besides, does it not seem that "we want to avoid ... self-teaching courses" and "We've been encouraged to experiment" are mutually exclusive terms? I would like, in good faith, to emphasize the latter and may the best meme win.--Dnjkirk 16:59, 17 October 2006 (UTC)
 * Many of the "books" at Wikibooks are, in fact, rather like self-teaching courses. You could try to argue that creating dictionary entries or encyclopedia articles for courses is good here, too, but really, that stuff belongs elsewhere if it qualifies to be elsewhere.  It can then be linked from here.  Otherwise you'll end up having people duplicating effort on both ends, and that's just silly.  The Jade Knight 06:54, 18 October 2006 (UTC)
 * I think that the point in contention is the difference between self-learning (ie: from a textbook) and something that requires interaction. Wikipedia/Wikibooks are great for autodidacts (self-learners) that want to read up on topics...however I'm thinking that the shift to wikiversity is that there is a participation component involved.  Granted, this can be carried out in a variety of ways, but due to the nature of wikiversity - writing a standalone self-directed course is going to be difficult and would probably find more efficient use in wikipedia/wikibooks.  --Kfitton 16:38, 18 October 2006 (UTC)
 * FYI: there is now a course available which has interaction: Thucydides: The Peloponnesian War (431 - 404 BC)
 * We have each week chat sessions - until now 12 (and here the logs). We are happy, if you join, Erkan Yilmaz uses the Wikiversity:Chat (try) 12:02, 24 March 2008 (UTC)
 * Doesn't really seem like this belongs here. Anyway, I'm listing on the main page.  The Jade Knight 09:32, 25 March 2008 (UTC)

Debate instead of course
I am a Dutch historian who wants to help with this project. I am not against courses. Everybody can teach or be teached when they want to. What i meant with this header is that i want to organize debates instead of courses. The reading of literature will be mandatory, but there will be no teacher with the authority to give grades. Instead, truth will be determined through debates, in which it is not obliged to change views. Views will be defended by referring to the literature. This way all remarks made during the debate can be checked by reading this literature.

The first debate i would want to start is about a book called 'Death, Desire and Loss in Western Culture' by Jonathan Dollimore (1998). This book is part of the history of ideas and is more a philosophical topic, then a historical one. However, it gives a good insight on several important aspects of the western culture.--Daanschr 20:39, 15 November 2006 (UTC)
 * Cool. I'm against givening grade unless they are for improvement. Hitler's Germany seems to be run the way you are talking about.  It would be nice to work on a book that in available to everyone.  Would quoting passages be against copyright?--Rayc 16:52, 22 November 2006 (UTC)

Sorry for the late reply. I didn't put this page on watch. I would like to join Hitler's Germany, if there is still some place. I have read many books about Germany in that period, especially about the German occupation of the Netherlands.

I don't know about copyrights. I know that many books quote small passages, but i don't know if they have to pay for these.--Daanschr 15:12, 7 December 2006 (UTC)

 * According to the local community college faculty guide that I have: "fair use in the US copyright law permits limited use of portions of a copyrighted work without the owner's permission for purpose such as criticism, comment, news reporting, teaching, scholarship, or research.  Section 107 of the Copyright Act establishes four basic factors to be considered in deciding whether a use constitutes a fair use. 1: The purpose and character of the use, invluding whether such use is of a commercial nature or is for non-profit educational purposes.  2: The nature of the copyrighted work.  3: The amount and sustantiality of the portion used in relation to the copyrighted work as a whole.  4: The effect of the use upon the potential market for or value of the copyrighted work."   --Kfitton 12:38, 16 March 2007 (UTC)

Proposed: Department of Indic History
I see that a "History of India" course has been requested. Now as we all know India's history would be rather difficult to fit into a single course, and thus I would like to head up development of of the new program. Any comments or suggestions for general development would be appreciated. Nmpenguin 07:22, 30 November 2006 (UTC)

 * Is there enough content to make an entire Department of Indic history? This is only meant to be an honest question.  I would think we could certainly come up with four or five courses, maybe even eight or nine, but a Department would in my mind offer several, several different courses.  Admittedly, I am not incredibly knowledge about the history of India other than to say it is fairly complex. So my question to you nmpenguin is this:  would there be enough material to fill several courses and make a full department?  Westernhistoryus 05:17, 15 March 2008 (UTC)
 * I don't see why not; India has a long and varied history, and many, many books have been written about it. We have a department of Canadian History, why not Indian?  That said, the Department is already there.  The Jade Knight 09:29, 25 March 2008 (UTC)

Stone age - Iron age
Are there any plans to incorprate these topics into this school? If there are I would be willing to help. Think outside the box 10:57, 11 January 2007 (UTC)

It's possible, but at that point you are probably going to run into anthropology/archeology. Might want to check around wikiversity and see if anything like that is already being worked on. --Kfitton 16:31, 12 January 2007 (UTC)

 * Do we have Anthropology or Archeology departments/schools here? It'd be good to work with them if so.  The Jade Knight 10:15, 28 June 2007 (UTC)

 * Yes, we do. I'm the only active member of the archaeology school though. --Danfly 14:15, 27 June 2008 (UTC)

 * Keep us informed if you'd like to do any cross-departmental stuff, eh? The Jade Knight 02:19, 3 September 2008 (UTC)

Course suggestion
I think it would be really interesting if we could have a course/project on the history of the Jews. I just think its a very interesting subject and would love a course on it... Feather 12:29, 13 February 2007 (UTC)

 * I am doing some papers and research on American Jews and their actions, or inactions, in the U.S. before and during World War II, but I admit that a more complete course on the subject might be interesting. Sekhmetdesign 21:29, 21 May 2007 (UTC)

interesting Wikipedia search tool
timesearch--JWSchmidt 14:00, 28 February 2007 (UTC)

 * That's cool. The Jade Knight 09:27, 1 March 2007 (UTC)

Historiography Course
Hi all, I am willing to help out in starting a course on the 'philosophy of history' or historiography. In my opinion this course should discuss the different types of history, ie: qualitative history and quantitative history, the incorporation of different disciplines in history, how to correctly 'practice' history. I am very adament about creating this course so any feedback or suggestions would be greatly appreciated Dctrainor 14:21, 23 November 2007 (UTC)
 * Welcome, thank you for the participation. We are a wiki. Just Be bold. If you need feedback on something, write here or in the Colloquium. Erkan Yilmaz ( Wikiversity:Chat, wiki blog ) 15:54, 23 November 2007 (UTC)
 * Does Anyone have any background in Historiographical Studies? If so, please contact me. --Dctrainor 20:39, 24 November 2007 (UTC)
 * Great idea. The Jade Knight 03:36, 14 March 2008 (UTC)

Wikipeida project
This might be of interest to Wikiversity participants: w:Wikipedia:Working group on ethnic and cultural edit wars. --JWS 13:43, 23 January 2008 (UTC)

Medieval History
I did a search relating to medieval history but could not find any information. I would be very interesting in working with fellow lecturers or professors in getting a programme set up in this field. Alas I know nothing about the procedure needed in setting forth such an endeavour. I have a username on Wikipedia. Do I make one on Wikiversity as well? My username does not work on this site. Contact me at celindgren@panola.com

72.24.148.150 07:02, 19 February 2008 (UTC)
 * Hello, yes your Wikipedia account does not work here. There is no need to create an account here - but it brings advantages: e.g. your IP is not known, people can write on your talk page, because due to switching IPs you may miss messages, ...
 * About the programme: what do you have in mind actually ? I would say create a page called: Topic:Medieval History and jump right in with your ideas there! Then people can see some concrete thing - Be bold ! If you need help with reviewing, collecting feedback, ... feel free to knock at my talk page, ok ? Though I am most of the time much more in the past: Thucydides: The Peloponnesian War :-) Erkan Yilmaz ( Wikiversity:Chat, wiki blog ) 07:30, 19 February 2008 (UTC)

title: School talk:History/Archive 1


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User:Amorfed

Anna Sidorenkova, Saint-Petersburg I love old movies, Baltic and Scandinavian countries, I work on the 4th step, study French and hypnosis.

title: User:Amorfed


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Template:User knowledge description-4

This user is a professional learning content provider / teacher on the subject of

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Template:User knowledge subcategory description-4

These users are professional learning content providers / teachers on


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Category talk:Knowledge user templates

Should individual users be in here? How does one get them out of this? The Jade Knight 08:41, 5 September 2008 (UTC)

title: Category talk:Knowledge user templates


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User talk:McCormack/policy on religious content

Interesting work here. I think you've misplaced the issue, however; the "academic objectivity" problems are universal ones, not limited to religion—if a psychology project asks "what is the most effective way to train a dog to roll over?", it's the exact same as if a religion project asks "what kinds of people go to heaven"? Both need attribution to be more accurate (and even within the sciences, and especially the social sciences, there can be significant disagreement over what is best or correct). The same applies to all disciplines. There is no need to single out religion here, as any relosophy (religions, philosophies, and most ideologies included) can be just as destructive or misleading. The Jade Knight 09:27, 5 September 2008 (UTC)
 * Hi. The page was an early draft. Yes - you are quite right that the issue is a universal one. I'd been trying to narrow the context intentionally. The reason for singling out religion is that it is one (of a very few areas) which are especially contentious. But I'm not really actively working on this draft now. --McCormack 09:48, 5 September 2008 (UTC)
 * Ok. Yes, religion and politics are among the most contentious areas.  The Jade Knight 10:01, 5 September 2008 (UTC)


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User:Richardva

Richard

New wikiphite, passionate about knowledge and learning.

Bio

Born, bred and raised in Durban, South Afica

Schooled at Northwood High School

Studied at:

 * Natal University, Howard College
 * UNISA

Work info:

 * Student 2001-2003

 * Outdoor Educator 2001-2004

 * Educator 2004-2007

 * Technical Writer 2008

More About Me:

DIY enthusiest

Amateur Chef

Fly fishing, camping, hiking and climbing

Member of the World Organisation of Scout Movements

title: User:Richardva


text:
User:Eml4500.f08.FEABBQ.koby

FEABBQ.koby
Welcome to Eml4500.f08.FEABBQ!!

Link to group page: User:Eml4500.f08.FEABBQ

Homework Pages

 * Homework 1
 * Homework 2
 * Homework 3
 * Homework 4
 * Homework 5
 * Homework 6
 * Homework 7

FEABBQ Team Members:

 * Esmail Hamdan
 * Jose Jayma
 * Grant Stark
 * Nik Vitt
 * William Kurth
 * Andy 'I vandalize people's pages in slight yet funny ways' Kobyljanec

EML 4500 Class Homepage:
User:Eml4500.f08

title: User:Eml4500.f08.FEABBQ.koby


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User:FEA4500.f08.FEABBQ.Hamdan

 * Esmail Hamdan

title: User:FEA4500.f08.FEABBQ.Hamdan


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User talk:EML4500.f08.FEABBQ.Hamdan

 Hello EML4500.f08.FEABBQ.Hamdan, 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! --JWSchmidt 14:11, 5 September 2008 (UTC)

title: User talk:EML4500.f08.FEABBQ.Hamdan


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User:EML4500.f08.FEABBQ.Hamdan

=Welcome to Esmail's Wiki Page for FEA=

Group Announcements:
This is my page  THIS IS A BIG RED BOX
 * 09/11/08 Posted nosed for Week one

 * Hey Group, this is my Wiki Page and I will be happy if we started working on the homework soon.

Homework Links:

 * 1) Homework-1
 * 2) Homework-2
 * 3) Homework-3
 * 4) Homework-4
 * 5) Homework-5
 * 6) Homework-6
 * 7) Homework-7

Class Notes Links:

 * 1) Notes to Aug.29
 * 2) Notes to Sep.05
 * 3) Notes to Sep.12
 * 4) Notes to Sep.19

FEABBQ Team Members:

 * Esmail Hamdan
 * Jose Jayma
 * Grant Stark
 * Nik Vitt
 * William Kurth
 * Andy Kobyljanec
 * FEABBQ Group User Page
 * Group Site
 * Class Site

title: User:EML4500.f08.FEABBQ.Hamdan


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User:Eml4500.f08.FEABBQ.koby/HW1

Graphics
Matlab is capable of producing a variety of mathematical graphs and figures in 2 and 3 dimensions. The basic commands to use these functions are:

Planar 2d Plots

The plot(x,y) function will create a linear graph if x and y are both 1d vectors of the same length. The first variable in the plot function is the horizontal axis, and the second is graphed on the vertical. The easiest way of producing a 1d vector is using colon notation:

The following is a graph of a sin wave from -4 to 4. Adding shown in the code above is the syntax for adding titles and axis labels using the title and xlabel/ylabel commands respectively.

Streamlined code exists for graphing functions as well. First, an M-file must be created such as the following:

Using this code would now create a 2d graph from -1.5 to 1.5:

2d parametric graphs can also be created in Matlab. The following code and Figure 3 demonstrate:

Annotating Graphs

Graphs are easily annotated in Matlab as well. Typing in the following commands will label the active figure. The format is like:

Other visual features are available as well:

All of these visual modifications should be performed after the plot command.

Multiple Graphs on the Same Figure

There are different ways to place multiple graphs onto the same Matlab figure. The first is to overload the  function. The following code and Figure 4 show how this can be done:

The  command can also be used. When hold is on, every plot graphed will go onto the active figure. Turning hold off will create a new figure for each new graph, which is the Matlab default.

Using Different Colors and Line Types on Graphs

Sometimes the default blue solid line in Matlab graphs can get a little boring. To add a little variety to your graphs, there are several commands that can be incorporated into the  function:

These commands are used inside single quotation marks inside the  function. would plot a dashed red line and  would plot a green dotted line.

Other Types of Graphs

There are several other types of graphs which Matlab can produce. Although this guide does not have the details for them, they can all be easily found using the  command.

 * Polar
 * Bar
 * Hist
 * Quiver
 * Compass
 * Feather
 * Rose
 * Stairs
 * Fill
 * Subplot

Graphics Hardcopy

Oftentimes it is necessary to print a graph from Matlab. This is most easily done with the convenient 'Print' menu option on the Figure. It is normally easier though to use 'Save as' and save the graph as a .jpg or other type of graphics file. For the more adventurous, Matlab has a  command which will print the active graphics item. The  option can also be used to append a different saved file to the current graphics item for printing. Just use the format.

3-D Line Plots

There are few more impressive ways to show off Matlab skills than producing colorful 3-D plots. The  command can easily plot in 3 dimensions, just like   plots in 2 dimensions. The following example shows how a 3-D plot (Figure 6) can be parametrically created:

All of the settings applicable to 2-D plots (including axis labels and commands, titles, colors, etc) can be used on a 3-D plot as well.

3-D Mesh and Surface Plots

The mesh and surf functions can create 3 dimensional representations of matrices, either with a wire mesh or solid surface. If a single matrix can be inputed into either function, the z value is the matrix value at point (x,y) (row, col). Figures 7 and 8 show the mesh and surf functions being used to graph the 'eye' (identity) matrix:

3-D functions can also be graphed using mesh and surf in conjunction with the  function. Combined with colon notation,  creates an x-y rectangle in which a function is graphed. The following code and Figure 9 show how a 3-D function can be defined and graphed:

There are several ways to change the appearance of a 3-D graph in Matlab. First of all, the  command will affect the superimposed mesh lines on a surface graph. Various color profiles can also be experimented with. The following commands can be used like this:

Any of the functions to change the appearance should be used after the graph has been made.

Graphs can also be produced parametrically with M-files. Check the guide for further information on this, and Matlab's 'Handle Graphics' which can produce advanced graphs and plots.

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


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User:EML4500.f08.FEABBQ.Hamdan/HW-1

Topics covered

 * 1) Class info
 * 2) WikiMedia
 * 3) Teams

1- Class info:

 * Syllabus:

Instructor :
 * Dr. L. Vu-Quoc,
 * Tel: 392-6227
 * E-mail:vu-quoc@ufl.edu
 * Office: NEB 135 (New Engineering Building)
 * Classroom: FLG 270
 * Class time: MWF, period 8 (3:00pm - 3:50pm)
 * Office hours: MWF, period 9 (4:05pm - 4:55pm)
 * web site: WWW.mae.ufl.edu/~vql

TAs:
 * 1)Nicolas Vigroux
 * Office: NEB 109, Tue, periods 3 and 4 (9:35am - 11:30am)
 * Tel: 846-3027
 * E-mail: nvigroux@ufl.edu

 * 2)Sung-Uk Zhang
 * Office: NEB 109,Thu, periods 6 and 7 (12:50pm - 13:40pm)
 * Tel: 392-3347
 * E-mail: zsunguk@ufl.edu

Exams Schedule:
 * 1) There are no scheduled make-up exams
 * 2) All exams are closed books, closed notes
 * 3) with a 4.25"x5.5" (half a letter-size paper) formula sheet allowed (handwritten)
 * 4) calculators can solve systems of linear simultaneous equations
 * 5) NOT allowed are laptops and any hand-held devices

Exam Dates:
 * 1) Exam 1: Wed, 24 Sep 2008
 * 2) Exam 2: Wed, 22 Oct 2008
 * 3) Exam 3: Wed, 03 Dec 2008

 * The grading will be 23% for every exam and 31% for the homework and projects.

 * to log on the class website:
 * 1) www.mae.ufl.edu/~vql
 * 2) Teaching
 * 3) Course website
 * 4) EMl4500
 * 5) Pass Word is: (fall08.wiki)

2- Wikimedia

Each member of a team has to create an account with Wikiversity using the format: (EML4500.f08.TEAMNAME.LASTNAME)

The idea of using wiki comes for many reasons:

 * Wiki is free
 * The articles are written by users
 * Can be edited
 * Previous versions of the article are available in the history or archive
 * Can be accessed from anywhere
 * Can be used on an international level
 * Stronger servers,( stronger than ELS ... )

3- Teams

 * Five to six people per group
 * Team Name: 4 to 6 characters
 * Email the TA:
 * Team Name
 * Members Name
 * UF ID Numbers

 * The team will work on homework and projects together to create a wiki page for every home work including all lecture notes associated in solving the homework. the team will have a coordinator/ leader that will email the archived link of the homework to the TAs at a specified time. the stamped time on the archived has to be before the deadline. The archived version will never be changed!! team members also will evaluating each other on every project.

 * The class had a major problem with the accounts on Wikipedia and we had to use Wikiversity instead. it works the same and give the same benefits to the class

==schematics of trusses FBD

Figure 1

=Steps to solve simple truss system described above=

1 Global Picture (description) at structure level

 * Global degrees of freedom (disp. dofs)
 * Global Forces

Actually the diso dofs are partitioned into:
 * a known part e.g., fixed dofs
 * an unknown part solved using FEA

Similarly for the global forces:
 * a know part, Applied Forces
 * an unknown part, Reactions

2 Element Picture:
 * Elem dofs
 * Elem forces

3 Global FD relationship
 * Elem stiffness matrices in global coord. sys.
 * Elem force matrices in global cooerd. sys.
 * Assembly of elem stiffness matrices and element forces matrices into global FD relation:

K.d=F

4 elimination of known dofs to reduce the global FD relation

5 Compare element forces from now known d

6 compare reactions (unknown forces)

Scalar functions
built in functions that operate on scalars or individual elements of a matrix. The most commonly used of these functions are as follows:

 * sin
 * asin (arcsin)
 * exp (exponential)
 * abs
 * round
 * cos
 * acos (arccos)
 * log (natural log)
 * sqrt
 * floor
 * tan
 * atan (arctan)
 * rem (remainder from division)
 * sign
 * ceil

Vector functions
functions perform actions on vectors in a "column by column" fashion and produce a row vector. The transpose can be used to operate on a row by row basis. Some of those functions are:

 * max
 * min
 * sort
 * sum
 * prod
 * median
 * mean
 * std
 * any
 * all

Matrix functions
The following is a list of matrix functions for Matlab. These functions can be accessed using different commands.
 * eig                (eigenvalues and eigenvectors)
 * chol               (cholesky factorization)
 * svd                (singular value decomposition)
 * inv                (inverse)
 * lu                 (LU factorization)
 * qr                 (QR factorization)
 * hess               (hessenberg form)
 * schur              (schur decomposition)
 * rref               (reduced row echelon form)
 * expm               (matrix exponential)
 * sqrtm              (matrix square root)
 * poly               (characteristic polynomial)
 * det                (determinant)
 * size               (size)
 * norm               (1-norm, 2-norm F-norm)
 * cond               (condition number in the 2-form)
 * rank               (rank)

Command line editing and recall
Matlab Editing and function keys:

 * left/right arrows scrolls the cursor left and right

 * up/down arrows scrolls up and down from line to line

 * backspace deletes the character left of the cursor

 * delete deletes the character left of the cursor

 * home moves the cursor to the beginning of the line

 * end moves the cursor to the end of the line

Go Back

title: User:EML4500.f08.FEABBQ.Hamdan/HW-1


text:
User:EML4500.f08.FEABBQ.Hamdan/HW-2

Euler Cut

Go Back

title: User:EML4500.f08.FEABBQ.Hamdan/HW-2


text:
User:EAS4200c.f08.blue.c

User page for Tom Sexton, member of Team Blue.

Because the shear stress is greatest at the top and bottom of the beam section (where z = b/2), the equation of shear stress can be rewritten as follows: $$\sigma = \frac{Mz}{I}  \Rightarrow   M=\frac{2I\sigma\ _{allowable}}{b} $$

Thus, it is necessary to find the value of I in terms of b (recalling that a can be written as a function of b: a=L/2-b). From the problem parameters we know that for this instance, Mmax = Tmax. Because Mmax has been determined, it must only be put into the relation:

$$\tau _{max}=\frac{T^{(1)}_{max}}{2a^{(1)}b^{(1)}t}=\frac{M^{(1)}_{max}}{2a^{(1)}b^{(1)}t}$$

Now check the values of $$\tau _{max}$$ with the value of $$\tau _{allowed}$$.If $$\tau _{max}$$ is larger than $$\tau _{allowable}$$ the optimal ratio of $$\frac{b^{(1)}}{a^{(1)}}$$would be acceptable. But $$\tau _{max}$$ is smaller than $$\tau _{allowable}$$, then the optimal ratio of $$\frac{b^{(1)}}{a^{(1)}}$$ would be unacceptable

Case 2
For this case we assume that the shear stress is eqaul to the maximum allowable shear stress in the section. Then we will test to see if the normal stress falls within acceptable tolerances (notably, less than $$\sigma _{max}$$)

By the equation given earlier in the problem the value of T becomes:

$$T=(2t\tau _{allowable})(ab)$$

Where the dimensions of the rectangle ab are equal to one another, hence a square. Therefore if the total perimeter of the square is L and all sides are equal, both a and b are equal to L/4. Plugging this quantity into the previous equation and using the given relation that M=T, we have:

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

Using this relation and the previously defined equation for normal stress:

$$\sigma ^{(2)}_{max}=\frac{M^{(2)}_{max}b^{(2)}}{2I^{(2)}}$$

We can find $$\sigma ^{(2)}_{max}$$ and compare it with the allowable normal stress. If the maximum normal stress is less than the allowable shear stress, then the ratio of b to a for case 2 is acceptable. But, if it is greater, then that ratio is not correct.

Solving Case 1
First the moment of inertia, I, must be computed. This is done by summing the moments of inertia of each of the four parts of the section. In order to do this, the Parallel axis theorem must be applied. Solving for the horizontal axis yields:

$$I=\frac{tb^{2}}{6}(3a+b)$$

And with the relation a=L/2-b, the plot of f(b)=I/b is shown to the right.

Taking the derivative of the function f(b) yields the maximum value of the curve to be b(1)=3L/8. Thus the ratio of $$\frac{b^{(1)}}{a^{(1)}}$$ is equal to 3 and the value of a(1) is found to be L/8. Solving for $$\tau _{max}$$ with the values of a(1) and b(1) yield:

$$\tau _{max}=\frac{M^{(1)}_{max}}{2a^{(1)}b^{(1)}t}=\frac{32M^{(1)}_{max}}{3tL^{2}}$$

but because this larger than half of $$\tau _{allowable}$$ this case is not possible

HW2 Contribution

 * {| class="toccolours collapsible collapsed" width="100%" style="text-align:left"

! Homework Solution: Triangle Area Proof

Problem: prove that $$A_{BEC}=\frac{1}{2}(ED)(BC)$$

Solution: The area of the triangle BED is calculated from the formula for the area of a right triangle: $$A=\frac{1}{2}bh$$ b= lenght of horizontal base h= length of vertical height Thus, the area of triangle BED is

$$A_{BED}=\frac{1}{2}(ED)(BD)$$

and the area of the interior right triangle CED is

$$A_{CED}=\frac{1}{2}(ED)(CD)$$

Therefore, the area of triangle BEC can be found by subtracting these two areas:

$$A_{BEC}=\frac{1}{2}(ED)(BD)-frac{1}{2}(ED)(CD)=\frac{1}{2}(ED)(BC)$$

 * }

title: User:EAS4200c.f08.blue.c


text:
User talk:Eas4200c.f08.aero.E

 Hello Eas4200c.f08.aero.E, 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.
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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! --JWSchmidt 14:41, 5 September 2008 (UTC)

This is my page.

Licence categorisation
Don't add the category in the image, put only the licence template, the template add itself the correct category.Crochet.david 16:35, 7 November 2008 (UTC)

title: User talk:Eas4200c.f08.aero.E


text:
User:Eml4500.f08.FEABBQ.vitt

EML 4500 Class Homepage:

 * EML4500.F08

Group Page:

 * FEABBQ

FEABBQ Team Members:

 * 1) Nik Vitt
 * 2) Esmail Hamdan
 * 3) Jose Jayma
 * 4) Grant Stark
 * 5) William Kurth
 * 6) Andy Kobyljanec

My Contributions

 * 1) Notes to Sep.03

title: User:Eml4500.f08.FEABBQ.vitt


text:
Wikiversity talk:Main Page/Introduction

The link to the Student Union should be replaced (at least for now) with one to Portal:Participants. The Jade Knight 15:07, 5 September 2008 (UTC)
 * I had a look at Portal:Participants and it seems rather unhelpful and undeveloped in its current state. I had a hunt around the place and found Learning goals, where new students once started to collect their requests or state their intentions for learning. This might be a more useful page for the time being, until there is a well-developed students portal. --McCormack 11:31, 10 September 2008 (UTC)
 * I agree that Learning goals is better than Student union. --JWSchmidt 11:58, 10 September 2008 (UTC)

Requestː Remove "heightː100%" for this box
Hi. Might that be possible to avoid "heightː 100̥%" in table/td for this template? For an unknown reason it looks good on the online version but this is not how it should be and worse the offline snapshots (ZIM files) have as a consequence a gigantic box with a lot of empty space. This should be achieved, I think, by calling TemplateːRobelbox with parameter "height" like "none". This would be really helpful. Regards. Kelson (discuss • contribs) 13:59, 31 October 2015 (UTC)

 * This isn't an issue specific to this instance of Robelbox, but applies to all of them. I believe the correct default should be auto rather than 100%.  I've made the change.  Let me know if there are still issues.  -- Dave Braunschweig (discuss • contribs) 14:56, 31 October 2015 (UTC)

 * Thank you Dave for the quick answer and action. I have tested again and it works perfectly. I hope I can use your expertise with a smaller problem impacting the home-page in the offline snapshot too. On the Home page, we have in the bottom-right corner of a few boxes, the following links "view · discuss". These links don't make sense in a printed version or in an offline snapshot. On Wikipedia these kind of links are often marked with the CSS class "noprint" which avoid to have them printed and offline snapshots also rely on this CSS class. Does that exist on en.wikiversity.org? If "yes" wouldn't that make sense to apply it to this (template)? Regards Kelson (discuss • contribs) 17:04, 31 October 2015 (UTC)

 * Yes, we have noprint available. And yes, I agree that it should be applied here.  But I can't find where those labels are coming from in this situation.  If you can find them, I'll try to figure out how to hide them.  -- Dave Braunschweig (discuss • contribs) 21:13, 31 October 2015 (UTC)

 * Might that be Template:FOTD Kelson (discuss • contribs) 22:07, 31 October 2015 (UTC)

 * Might be. Did the most recent change resolve this issue?  -- Dave Braunschweig (discuss • contribs) 23:44, 31 October 2015 (UTC)

 * You don't have applied the "noprint" class to the "div" containing "view - discuss", but to the one just before. If you want to applied it to both, you might also want to apply it to the "hr" just before. Kelson (discuss • contribs) 06:46, 1 November 2015 (UTC)

 * HR can't be hidden without also editing that template and adding a style parameter. I moved noprint to the view - print div.  -- Dave Braunschweig (discuss • contribs) 13:57, 1 November 2015 (UTC)

 * Perfect. Thanks a lot. Kelson (discuss • contribs) 14:14, 1 November 2015 (UTC)

title: Wikiversity talk:Main Page/Introduction


text:
User:Eml4500c.f08.gravy.mmm/Lecture 1

Notes

Online sources for free college resources.

Wikipeida, wikversity, MIT. Open course ware.

Labeling system
1.      Number in a triangle is the global label for an element

2.      Number in a circle is the global label for a node

3.      Number in a square is the local label for a node

Next big step: Force-Displacement relation (FD)

$$\begin{Bmatrix} f_1 \\ f_2 \end{Bmatrix}_{2X1}=\begin{bmatrix} k  &- k  \\-k &k    \end{bmatrix}_{2X2}*    \begin{Bmatrix} d_1 \\ d_2 \end{Bmatrix}_{2X1}$$

Case 1; observer sits on node 1

$$\ f_2=k(d_2-d_1)\,$$

Case 2: observer sits on node 2

$$\ f_1=-f_2=-k(d_2-d_1)=k(d_1-d_2) \,$$

Ch1. : Big Picture
1.1 Discretization

1.1.1         Plane Truss element

1.2      Assembly of element

Ex. 1.4 Fire-bar truss

1.4  Element solution of model validity

1.4.1         Plane Truss element

Steps to solve simple truss systems

1.      Global picture (description) At structures level

·        Global degrees of freedoms (dofs) and displacement degrees of freedoms (disp. dofs)

·        Global forces

Actually the disp dofs are partitioned into:

·        A known part, e.g fixed dofs, constrains

·        An unknown part: Solved using FEM

Similarly for the global forces:

·        A known part: Applied forces

·        An unknown part : Reactions

2.      Element Picture:

·        Element  dofs

·        Element forces

·        Either  of the above in global coordinates systems or in local coordinates systems

3.      Global FD relation

·        Element stiffness matrices in global coordinates

·        Element force matrices in global coordinates

·        Assembly of element stiffness matrix and element force matrix into global FD relation

$$\ K_{nXn} * d_{nX1}=F _{nX1} \,$$

4.      Elimination of known dofs. To reduce the global FD relation (stiffness matrix non-singular) invertible

$$\ \overline{ K_{mXm}} * \overline{ d_{mX1} }= \overline{ F _{mX1}} \,$$

M= number of unknown disp dofs

N= number of both known and unknown disp dofs

k non singular so k-1 exists (k invertible)

$$\ \overline{ d_{mX1} }= \overline{ K^{-1}_{mXm}} * \overline{ F _{mX1}} \,$$

5.      Compute element forces from  now known d= element stresses

6.      Compute reactions. (unknown forces)

Inclination angle:

title: User:Eml4500c.f08.gravy.mmm/Lecture 1


text:
User:Eml4500.f08.RAMROD.A

TEAM RAMROD
[Amory T.] [Chris P.] [Jeff  H.] [Dan   O.] [Kevin S.] [Chris F.]

Course HW Table
[HW Table]

Team Homeworks
/HW1

/HW2

/HW3

/HW4

/HW5

/HW6

/HW7

My Contributions
/MyPartForHW1

/MyContributionHW2

/MyContributionHW3

/MyContributionHW4

/MyContributionHW5

/MyContributionHW6

/MyContributionHW7

title: User:Eml4500.f08.RAMROD.A


text:
User talk:Eml4500.f08.RAMROD.A

 Hello Eml4500.f08.RAMROD.A, 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! --JWSchmidt 15:30, 5 September 2008 (UTC)

title: User talk:Eml4500.f08.RAMROD.A


text:
User talk:Pa.us.wiki media dot org

Hello, welcome around here. I'd be interested in the reason for that image on the user page - would you mind sharing the story ? I hope we can help you succeed in your learning goals. Below more info about Wikiversity, Erkan Yilmaz uses the Chat (try) 15:47, 5 September 2008 (UTC)

 Hello Pa.us.wiki media dot org, 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! Erkan Yilmaz uses the Chat (try) 15:47, 5 September 2008 (UTC)

title: User talk:Pa.us.wiki media dot org


text:
User talk:FREDDY~enwikiversity

 Hello FREDDY, 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! --The Jade Knight 15:56, 5 September 2008 (UTC)

Your account will be renamed
Hello,

The developer team at Wikimedia is making some changes to how accounts work, as part of our on-going efforts to provide new and better tools for our users like cross-wiki notifications. These changes will mean you have the same account name everywhere. This will let us give you new features that will help you edit and discuss better, and allow more flexible user permissions for tools. One of the side-effects of this is that user accounts will now have to be unique across all 900 Wikimedia wikis. See the announcement for more information.

Unfortunately, your account clashes with another account also called FREDDY. To make sure that both of you can use all Wikimedia projects in future, we have reserved the name FREDDY~enwikiversity that only you will have. If you like it, you don't have to do anything. If you do not like it, you can pick out a different name.

Your account will still work as before, and you will be credited for all your edits made so far, but you will have to use the new account name when you log in.

Sorry for the inconvenience.

Yours, Keegan Peterzell Community Liaison, Wikimedia Foundation 23:36, 17 March 2015 (UTC)

Renamed
 This account has been renamed as part of single-user login finalisation. If you own this account you can |log in using your previous username and password for more information. If you do not like this account's new name, you can choose your own using this form after logging in: . -- Keegan (WMF) (talk) 06:08, 19 April 2015 (UTC)

title: User talk:FREDDY~enwikiversity


text:
User:Paul~enwikiversity

My name is Paul and I would like to tell you a little about myself and how I got involved in Abaya School in Ethiopia. Two years ago I was invited to help with the setting up and running of the Arba Minch Festival of a Thousand Stars http://www.gughe.org/. Arba Minch is a city located in the province SNNPS (Southern Nations Nationalities and People's State) in South Ethiopia. Through my involvement in the festival I got to know the head teacher, staff and pupils of Abaya School, also in Arba Minch. I returned the following year to see if I could help the school and discovered that they have 2210 pupils and fewer books than I have in my office. I did what I was able to do during that visit which was a drop in the ocean. I managed to get a few hundred random books shipped to them with the help of the British Council and bought them some much needed equipment. Books, however, are not practical due to the remoteness of the region and the high cost of shipping. I promised to return this year and try to take the project forward. I have invested in a 320MG portable drive and my idea was to fill it with Wikiversity and related content. Teachers are currently relying on memories of books they borrowed during their training to develop lessons. My vision is to make Wikiversity available to them. They have two good computers and I am hoping to take some laptops with me. There is no internet connection and one is probably not going to be available in the foreseeable future due to political constraints, and technical problems like the lack of phone lines and unreliable electricity source. I am not well educated myself and my computer skills are somewhat limited. For this reason I need help in deciding what to download and how to achieve it.

title: User:Paul~enwikiversity