text:
User:Cwoo4792/enes100/Robot Arm 2

Link to team page: TFCWNS

Give instructor top 3 project choice list
1.Robot Arm 2.Robot end effector 3.Rube Goldburg

Write problem statement
Find a way to build a system that would raise and lower the robot arm, raise and lower the individual wires, and contract the end effector.

Assign Task1
Look up push/pull systems or think up of possible push pull systems to implement onto the robot arm.

Compare actual work done to Task1
My goal was to look up push/pull systems or think up of possible push pull systems to implement onto the robot arm and I came up with the idea of using a train wheel like system that pushes and pulls all in one rotation of wheel. This way we would only need a motor to move in one direction for me to raise and lower the arm. I also discovered with the help of one of the engineering room maintainers that I could utilize the Lego mindstorm nxt system and was able to create a pull system for the end effector.

Week1 Narrative
Week one of this project cycle my goal was to find ways to lift and lower the Robot arm. I started of by thinking a screw and bolt system that works by raising a platform by turning a long central screw. This would allow a platform to be lifted by turning the screw in one direction, and to be lowered when turned in the other. The problem with this design was that we didn't have the parts necessary to build it. I then thought of the Idea of using a type of train wheel system. This would allow a platform to be raised and lowered in one rotation of a wheel. I implemented this idea by using Lego Mindsorm pieces and I was able to get a system that lowered and raised the arm. Although it doesn't raise and lower smoothly, this is the kind of system that be the most probable to work for our arm considering parts available and time. I will continue to figure out the structural problems of this system so that it will be able to raise and lower the arm smoothly. I was also, with the help of Patrick, able to learn how to use a simple Lego Mindstorm nxt programming system to use on Lego motors. With this I was able to program a motor to pull the End effector string to enable grabbing. Here are some pictures of what I have:
 * http://commons.wikimedia.org/wiki/File:Robot_arm_raising_system_1_(lowered).jpg
 * http://commons.wikimedia.org/wiki/File:Robot_arm_raising_system_1_(raised).jpg
 * http://commons.wikimedia.org/wiki/File:Raising_system_(side_view).jpg
 * http://commons.wikimedia.org/wiki/File:Raising_system_(back_view).jpg
 * http://commons.wikimedia.org/wiki/File:Raising_system_(back_view_raised).jpg
 * http://commons.wikimedia.org/wiki/File:Lego_Mindstorm_motor_with_pulling_wheel_attached.jpg
 * http://commons.wikimedia.org/wiki/File:Raising_system_with_Lego_Mindstorm_motor_and_controller.jpg

Week1 Peer Review
Go to each team mates weekly summary wiki page. Read their activities and narrative. Then go the associated discussion page. Say something positive on this page. Try some constructive criticism. Add your name and a signature ~ by entering four tildes in a row to create a time and date stamp. Create a new category if another team mate has already commented here.

Assign Task2
Work on fixing problems with raising and lowering system by creating a more sturdy structure.

Compare actual work done to Task2
My goal was to work on fixing problems with the raising and lowering system by creating a more sturdy structure, but through further testing I found that with the train wheel system I would not be able to distribute the pulling and pushing torque evenly among the wires. I decided to just implement the train wheel pulling and pushing system to each wire by giving each wire a sliding system and motor.

Week2 Narrative
During Week two of this project I began by trying to refine the lift and lower system of the Robot arm however, I was unable to get any success in making this system lift the arm smoothly without getting stuck or tilted to one side. I then began exploring different ways to lift and lower the arm. I thought of using some sort of pulley system similar to that used in bicycle breaks by using fishing wire and hard plastic tubing but creating a structure for this would take longer than the time I had so I had to think of something different. Finally I referred back to the original idea of having a motor next to each wire except this time I would use the Lego motors. I then thought of incorporating the train wheel system to each wire rather than just one for all the wires. This way I wouldn't run into the problem of uneven push and pull. I was able to create a system like this to one of the wires and I will add one to the rest of the arms when time allows.
 * http://commons.wikimedia.org/wiki/File:Lego_Raising_and_Lowering_motor.jpg
 * http://commons.wikimedia.org/wiki/File:Lego_Raising_and_Lowering_motor_(Raised).jpg
 * http://commons.wikimedia.org/wiki/File:Plastic_tube.jpg
 * http://commons.wikimedia.org/wiki/File:Wire_raisers.jpg

Week2 Peer Review
Go to each team mates weekly summary wiki page. Read their activities and narrative. Then go the associated discussion page. Say something positive on this page. Try some constructive criticism. Add your name and a signature ~ by entering four tildes in a row to create a time and date stamp. Create a new category if another team mate has already commented here.

Assign Task3
Add lift/lower system to each one of the wheels and test it out to find if there are any problems.

Compare actual work done to Task3
My goal was to add a lift/lower system to each one of the wires and test it out to find if there are any problems. I was able to construct a frame to hold the two lateral motors with a lift/lower system attached. I was able to get the two lateral wires to correspond to a simple program which successfully raised and lowered the arm. The arm however, wiggled slightly from side to side when raising. This may be due to the fact that I was unable to connect a motor to the front wire which moved freely when the others were being raised and lowered.

Week3 Narrative
During this section of the Project I set out to add the other motors to the wires of the robot arm. I began by first trying to build a frame to hold the motors in place so that they could move the wires without themselves moving. I needed to make sure that the motors were placed in the right position to utilize the best and smoothest lifting and lowering motion. I was able to construct the frame by adding multiple cross beams that connected to the motors and to the axle posts around the top. I had to make sure both motors were symmetrical in where they were placed and how they were held in, in order for each of them to work the same. After finishing this I moved on to make a program so to test how it worked. I needed to slow the motors down so that the peg holding the wires into the top of the push/pull system wouldn't fall out. I made a motor command for both motors so that they would run for 0.125 seconds and then put a loop around it so that this would repeat over and over. This resulted in the motors acting somewhat like a stepper motor. When I ran the program the arm lifted and lowered repeatedly and the pegs didn't fall out. The arm however would somewhat sway back and fourth due possibly to the fact that the front wire was not connected to a motor. I need to glue all the pegs in and connect a front motor to the front wire. In addition I need to create a system to open and close the end effector smoothly.
 * http://commons.wikimedia.org/wiki/File:Motor_Frame_(back_view).jpg
 * http://commons.wikimedia.org/wiki/File:Motor_Frame_(side_view).jpg
 * http://commons.wikimedia.org/wiki/File:Motor_Frame_(front_view).jpg

Week3 Peer Review
Go to each team mates weekly summary wiki page. Read their activities and narrative. Then go the associated discussion page. Say something positive on this page. Try some constructive criticism. Add your name and a signature ~ by entering four tildes in a row to create a time and date stamp. Create a new category if another team mate has already commented here.

Assign Task4
Add front motor, glue pegs in, refine NXT programming, and create a better way to pull the end effector.

Compare actual work done to Task4
My goal of week 4 of the project was to add the front motor, glue the pegs in, refine the NXT programming, and create a better way to pull the end effector. I was able to add the front motor to the frame create a demonstration program and attach the wire of the end effector to a motor mounted at the rear of the frame. I decided that it would be better to leave the pins unglued and attach rubber bands so that the height of the wires could be adjusted.

Week4 Narrative
During this last segment of the Project I needed to work on mounting the forward motor to the frame, add an end effector motor, and make programs for the robot arm. I was able to figure out a configuration of Legos that could fit a front motor for the front wire and a back motor for the end effector. I then needed to make a program for the motors. The problem I have is that the nxt block only has 3 motor ports when I need 4. However I was still able to create a program that demonstrated its grabbing ability by only controlling the front wire and the end effector. I then was able to make a program that demonstrated it's range of motion by allowing all three wire motors to be powered simultaneously.
 * http://commons.wikimedia.org/wiki/File:Final_Robot_Arm.jpg
 * http://commons.wikimedia.org/wiki/File:Motors_and_NXT_Brick_controlling_the_robot_arm..jpg
 * http://commons.wikimedia.org/wiki/File:Side_view_of_control_system.jpg
 * http://commons.wikimedia.org/wiki/File:NXT_program_1.jpg
 * http://commons.wikimedia.org/wiki/File:NXT_program_2.jpg

Week4 Peer Review
Go to each team mates weekly summary wiki page. Read their activities and narrative. Then go the associated discussion page. Say something positive on this page. Try some constructive criticism. Add your name and a signature ~ by entering four tildes in a row to create a time and date stamp. Create a new category if another team mate has already commented here.

Complete Project Page
Follow the "project done" format.

Start Next Project Week0 activities
End of semester

title: User:Cwoo4792/enes100/Robot Arm 2


text:
User:Npsweet/enes100/Robot Arm

Link to team page: TFCWNS

Give instructor top 3 project choice list
ROBOT ARM

Write problem statement
Make the robot arm better and attch motors to make it move.

Assign Task1
Brainstom ideas to make the arm move mechanicaly with mototrs.

Compare actual work done to Task1
CAme up with diffrent ideas to make the arms move. Plan to make a device that can screw up and down moving the entire platform.

Week1 Narrative
Upload photos to wikimedia. Upload video to youtube. Convert all spreadsheets, documents, and presentations to wiki format and create wiki subpage of your page for each of them. Link to them here in a narrative that tells a story. High light the problems (engineering problems) you had and how you solved them.

Week1 Peer Review
Go to each team mates weekly summary wiki page. Read their activities and narrative. Then go the associated discussion page. Say something positive on this page. Try some constructive criticism. Add your name and a signature ~ by entering four tildes in a row to create a time and date stamp. Create a new category if another team mate has already commented here.

Assign Task2
Record what you are planning on doing for the team during the weekend between week1 and week2 of the project here.

Compare actual work done to Task2
Rationalize differences

Week2 Narrative
Upload photos to wikimedia. Upload video to youtube. Convert all spreadsheets, documents, and presentations to wiki format and create wiki subpage of your page for each of them. Link to them here in a narrative that tells a story. High light the problems (engineering problems) you had and how you solved them.
 * http://commons.wikimedia.org/wiki/File:Screw_system.jpg

Week2 Peer Review
Go to each team mates weekly summary wiki page. Read their activities and narrative. Then go the associated discussion page. Say something positive on this page. Try some constructive criticism. Add your name and a signature ~ by entering four tildes in a row to create a time and date stamp. Create a new category if another team mate has already commented here.

Assign Task3
Try to build the device that wll move the arms

Compare actual work done to Task3
Helped built a device that will build the arms using lego nxt. Look at soleniods but it would be to hard to attach them and power them. Also fount a screw like device inside a printer that may make moving the platform easier.

Week3 Narrative
Upload photos to wikimedia. Upload video to youtube. Convert all spreadsheets, documents, and presentations to wiki format and create wiki subpage of your page for each of them. Link to them here in a narrative that tells a story. High light the problems (engineering problems) you had and how you solved them.

Week3 Peer Review
Go to each team mates weekly summary wiki page. Read their activities and narrative. Then go the associated discussion page. Say something positive on this page. Try some constructive criticism. Add your name and a signature ~ by entering four tildes in a row to create a time and date stamp. Create a new category if another team mate has already commented here.

Assign Task4
Finish up with making the arms move and build a pully like device to pull middle string.

Compare actual work done to Task4
I used a motor to pull the string to close the claw. Then i fastened it on to the box.

Week4 Narrative
Upload photos to wikimedia. Upload video to youtube. Convert all spreadsheets, documents, and presentations to wiki format and create wiki subpage of your page for each of them. Link to them here in a narrative that tells a story. High light the problems (engineering problems) you had and how you solved them.

Week4 Peer Review
Go to each team mates weekly summary wiki page. Read their activities and narrative. Then go the associated discussion page. Say something positive on this page. Try some constructive criticism. Add your name and a signature ~ by entering four tildes in a row to create a time and date stamp. Create a new category if another team mate has already commented here.

Complete Project Page
Finished project page

Start Next Project Week0 activities
none

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

title: User:Npsweet/enes100/Robot Arm


text:
User:TFrancis3580/enes100/Robot Arm 2

Link to team page: TFCWNS

Give instructor top 3 project choice list
1. Robotic Arm

2. Ice Spikes

3. Robot Arm End Effector

Write problem statement
Improve upon the construted Robotic Arm and find some way to introduce mechanics into operation of the robotic arm.

Assign Task1
Brainstorm ideas on how to improve the robotic arm and discusss them with the team.

Compare actual work done to Task1
Decided to make separate version own robotic arm with a different end effect to compare with that of the old version so we can make improvements.

Week1 Narrative
Upload photos to wikimedia. Upload video to youtube. Convert all spreadsheets, documents, and presentations to wiki format and create wiki subpage of your page for each of them. Link to them here in a narrative that tells a story. High light the problems (engineering problems) you had and how you solved them.

Week1 Peer Review
Links To Week 1 Peer Reviews

Assign Task2
Continue to work on constructing a new robotic arm for comparison.

Compare actual work done to Task2
Rationalize differences

Week2 Narrative
Upload photos to wikimedia. Upload video to youtube. Convert all spreadsheets, documents, and presentations to wiki format and create wiki subpage of your page for each of them. Link to them here in a narrative that tells a story. High light the problems (engineering problems) you had and how you solved them.

Week2 Peer Review
Go to each team mates weekly summary wiki page. Read their activities and narrative. Then go the associated discussion page. Say something positive on this page. Try some constructive criticism. Add your name and a signature ~ by entering four tildes in a row to create a time and date stamp. Create a new category if another team mate has already commented here.

Assign Task3
Record what you are planning on doing for the team during the weekend between week2 and week3 of the project here.

Compare actual work done to Task3
Rationalize differences

Week3 Narrative
Upload photos to wikimedia. Upload video to youtube. Convert all spreadsheets, documents, and presentations to wiki format and create wiki subpage of your page for each of them. Link to them here in a narrative that tells a story. High light the problems (engineering problems) you had and how you solved them.

Week3 Peer Review
Go to each team mates weekly summary wiki page. Read their activities and narrative. Then go the associated discussion page. Say something positive on this page. Try some constructive criticism. Add your name and a signature ~ by entering four tildes in a row to create a time and date stamp. Create a new category if another team mate has already commented here.

Assign Task4
Record what you are planning on doing for the team during the weekend between week3 and week4 of the project here.

Compare actual work done to Task3
Contructed 2 designs for the end effector of the robotic arm out of lego pieces and documented on group members updates and improvements on the robotic arm.

Week4 Narrative
Robotic Arm Improvement Demonstration Video:

Robotic Arm Improvement Photos:

Robotic Arm Finger Component Propositions:

Week4 Peer Review
Nathan Sweet Week 4 Peer Review

Calab Woo Week 4 Peer Review

Complete Project Page
Follow the "project done" format.

Start Next Project Week0 activities
During this week you will perform the week0 activities of the next project.

title: User:TFrancis3580/enes100/Robot Arm 2


text:
Wikiversity:Community Review/Global bans

The Meta community is developing a process for deciding when to stop people from editing all projects (a "global ban").

 * What role should custodians have in carrying out global ban decisions?
 * When should custodians block Wikiversity participants because of a global ban decision?
 * How should custodians respond to requests to block people because of a global ban decision?

-- dark lama  20:39, 10 November 2011 (UTC)

Contribution from Thenub314

 * I think two key considerations are: did representatives from our community take part in the discussion at meta, and was the discussion publically announced here. This ensures everyone in our community was aware and had a change to represent their opinion as part of the global consensus.  But in cases when these two considerations are met, then I think a custodian should act.  So I think the answer to the second question is that we should respect the meta decision (at least initially) when these two criteria  are met.

 * Being a volunteer position I don't think we can require a custodian to ever block a user if they are uncomfortable doing so. But if a custodian is aware that a globally baned user is editing I think it is a reasonable procedure in the case of a global ban is to first block, and if an unblock is desired to re-invite the whole community to decide the merits of having him here vs the harm done the the project (e.g. cross-pollination issues).  Provided of course that in the Custodians opinion, the two considerations above are met.

 * As far as the first question goes I don't think there is any special responsibilities in carrying out the discussions. If you block then making the community aware of the global ban, and subsequent block should be enough.  The conversation can carry on from there by itself and which ever custodian decides to close, and undo the block if necessary. Thenub314 21:32, 10 November 2011 (UTC)

Contribution from SB_Johnny
I've done some poking around on meta, and it's pretty clear that the global ban issue is not something we can circumvent locally by "opting out", though there does seem to be movement towards allowing "local communities" (like ours) to ask for an appeal of a given ban if we have local consensus to do so. With that in mind, I think perhaps the best approach for us would be to poll the community if a particular case is seen as problematic (perhaps starting at WV:RCA, and then to WV:C if it looks promising).

As far as blocking locally to support global bans, I see reasons in favor as well as reasons against. On the one hand, perhaps the best way to handle it would be to allow any local user who is concerned to simply report accounts used to circumvent a ban to the stewards, either on the meta noticeboard or privately, since this would simply "take it out of our hands". On the other hand, the global locks may also prevent the user from editing their talk page or using email to make an appeal to the local community for consideration, so at least in that sense a local block gives us more flexibility.

Another thing I've found in the poking around both here and on meta is that at least some of the argument for ignoring or otherwise denying global bans here on WV seems to be for the purpose of providing a bulwark to prevent meta from being able to enact global bans, or at least to prevent them from being effectively imposed on users here who feel they might be subjected to one. If this is the case, I'd like to refer back to discussions held here some time ago regarding the use of this wiki as a political tool to affect other wikis (which I and at least some others felt was inappropriate, as beyond our scope). --SB_Johnny talk 14:14, 14 November 2011 (UTC)

Contribution from Marshallsumter
While these matters may be better left to the custodial community, I would like to insert these concerns. Wikipedia carries a lot of clout. Should a group there decide to globally ban any user, it may be difficult for WMF to prevent this. I believe we should strive to keep WV as independent as possible. Our first question should be, "Should we agree with the global ban?" My answer is emphatically No!. By maintaining our freedom to decide based solely on the contributions of a user here, I believe our first response must be a no until appropriate review has occurred. Even then caution is needed lest a wrongly steered consensus end up doing harm for which there is no recourse left inside WMF. I believe the probably overworked custodians are our first line of defense against a possibly overly rash decision from outside. The tone, if I may say, should be first to keeping as independent as possible rather than to 'how should we do what we're told?' Marshallsumter 23:19, 10 November 2011 (UTC)

I wanted to add this comment. After reading the discussion on meta, I'm convinced that processes already exist to handle potential 'criminal' activity throughout WMF. But, should these fail I believe we should allow appropriate action by outside enforcement on an individual basis only. And, I'm very cautionary about that because all too many governments would love to get further control on internet freedoms, such as contributing to various WMF projects. Having written that I must add that due process does not exist if even one project can ban or block wrongly and no way exists to undo it. Marshallsumter 02:05, 11 November 2011 (UTC)

Contribution from Bilby
I guess I have some thoughts. Short answer: I like the stance of block if somone is globally banned through a genuine community disccusion on Meta and it is clear that they are editing through the ban, and accept a community consensus to unblock if that's what later emerges. - Bilby 00:33, 11 November 2011 (UTC)
 * As a general rule, I see a need for global bans. Banning, by its nature, is reactive - the problem has to occur, and then we respond. So by the time we're banning someone locally, the damage has been done. If there is no possibility of a global ban, there is a real risk that a person could move from wiki-to-wiki, repeating the same damaging behaviour, even though the problems have been detected on other wikis.
 * The second argument is that the wider wiki community can be damaged by the actions of one wiki. To some extent this is true - the projects are connected, and major problems on one project will reflect on the WMF, if nothing else, and that in turn could affect them all. On those grounds the possibility of genuine global bans to protect the projects as a whole is something worth considering, but I'm not yet convinced of the extent that this holds.
 * The "all else being equal" means that I can see value in being able to override a global ban locally if there is strong consensus to do so. If the global model fails, then it may be the responsibility of the local models to respond.
 * This will all be moot if the new Terms of Use go through, as they will mean that editing through a global ban is a violation ot the Terms, and that places it outside of our hands. I'm assuming that any discussion here is dependent on the current Terms of Use being in place, and may not be relevant should the changes pass.

Contribution from Abd

 * What role should custodians have in carrying out global ban decisions?
 * None. Custodians are only responsible for what happens on Wikiversity. Global bans are a formalization of global lock decisions, that, by default, prevent an account from being used on any WMF wiki. Global lock decisions are made by stewards, who are responsible to the global community, and who are elected at meta. They serve meta policy, and that policy has always respected local consensus. If I'm correct, the pre-SUL software only allowed certain global tools that affected all wikis, and all of these have local whitelists to allow local admins to bypass them Thus a local wiki is not required to get meta permission to bypass meta decisions.
 * SUL accounts are exclusively global. Hence a global ban is properly decided and enforced at and through meta. However, global locks were designed only for spammers and vandals, not to over-ride the local right of decision. We should not have to decide if a decision at meta is "sound" or "unsound." Our custodians are responsible to this community, and are regulated by the policies that this community has established, which, wisely, do not turn over the responsibility of our custodians, to protect our users and our community, to some outside group making a decision at meta, whether that decision is proper or improper. It might indeed be proper to globally lock, Locally, though, a non-SUL user should be treated like all other users, and be free from harassment, from a need to defend himself or herself, if the user follows policy here.
 * When should custodians block Wikiversity participants because of a global ban decision?
 * Never. That's the long-standing proposed WV:Blocking policy. It is not a legitimate block reason. That does not mean that a globally banned user has some sort of immunity, but the local decision must be made based on local effects and policies.
 * How should custodians respond to requests to block people because of a global ban decision?
 * We should refuse such requests, while respecting complaints showing actual harm. Informing us of a global ban, and requesting review of editing, are fine. Demanding that we block without local policy violation is not. Stewards have the power to block local users, if there is true hazard, and they have done so in the past. When they did so in a manner that did not respect local consensus, the results have been highly disruptive. Stewards know to avoid that, so global ban enforcement is properly handled by stewards. Local consensus is clear that users are not to be blocked based on behavior elsewhere, with other protections and safeguards. For example, users are not to be blocked for old behavior, only for recent behavior, i.e., behavior likely to continue. Human behavior is situational, a person may be disruptive in one environment and constructive in another. A global ban, almost necessarily, only considers the general case.
 * A WV:Assembly process has been proposed to consider this issue. Assembly process is designed for slow but careful consideration of all issues around blocking policy. Comparatively, this CR is "emergency," i.e., we apparently need quick clarification of how to handle global bans, in spite of policy and precedents covering it.--Abd 23:14, 11 November 2011 (UTC)

Comments from Ottava Rima
The Global Ban discussions have been given plenty of notice and are handled properly at Meta. In situations like Poetlister, any Custodian who thinks that such an outright dangerous person should be unblocked or allowed to edit should be stripped of Custodianship for endangering the project. It isn't about forcing Custodians here to block people. It is about having them do their jobs. If you honestly think that people who use many sock accounts, impersonate others, and manipulate their way to higher privileges to steal personal information on others are appropriate for this project, then that individual isn't appropriate for this project. Ottava Rima (talk) 15:25, 12 November 2011 (UTC)

Comments from Simone Larctia
Custodians shouldn't support users who have disrupted more than one WMF project. Global bans should be enforced locally, even though there is currently still no procedure to appeal a global ban. -- Simone 23:27, 12 November 2011 (UTC)

Comments from Jtneill
I favour allowing users a clean slate per local wiki and I favour not basing local decisions on activities of the user in other Wikimedia projects or other on- or off-line settings.

If a global ban is made, then it is a Steward role to perform a global lock; it is not a local custodian responsibility. -- Jtneill - Talk - c 11:55, 14 November 2011 (UTC)

Comments from Thekohser
Any community that would "give up essential liberty, to purchase a little temporary safety, deserve neither liberty nor safety", as Benjamin Franklin once said. The independence of the Wikiversity community and process should come before a blind fealty to matters that happen on Meta. I am a case in point, given that I was issued a global lock from a Meta bureaucrat who was clearly out of process (and arguably out of control). The Commons, Wikibooks, Wikiversity, and other Wikimedia projects were intelligent enough to see that the Meta tyranny was misguided, and my account was restored. In return, they got 100% freely-licensed content of considerable quality, and no fuss at all about the terrors and troubles predicted (falsely) by the Meta overlord. In fact, when he saw that some of the other communities had evaluated his fraud and overturned it, he retired his tools in a huff. Please, Wikiversity, don't give in to false leaders on Meta who are merely trying to grab more power as a governing body, rather than (properly) a coordinating body. Wikiversity is perfectly capable of evaluating global ban recommendations that might emanate from Meta, on a case by case basis. To blindly accept all such recommendations as de facto rule is pure foolishness. -- Thekohser 17:26, 14 November 2011 (UTC)

Comments from Steven Walling
I'm not a regular Wikiversity editor, but as an interested party I do want to make a few statements/clarifications:

 * 1) Since the draft policy for global bans was first posted, we have added a paragraph which acknowledges the possibility of overturning a global ban, among other revisions.
 * 2) Ideally, Wikiversity custodians should not need to even ponder a decision about whether they have to enforce a global ban. If a global ban is successful, then the Stewards enact a global lock and that's that. Unfortunately you've run into the local sockpuppet issue already...
 * 3) I think that when a local sock of a globally banned user is identified beyond reasonable doubt, the wise decision is to block. But, as I said previously on Meta, it is very much intentional that the policy does not demand that sysops identify and block all sockpuppets of a globally banned user. Such a commandment would be ridiculous for a variety of reasons. As described by Thenub314 and others, ultimately this is like any other action that a sysop might take: it's a judgement call, and you're elected to such a position for your ability weigh community consensus and the needs of the project. I honestly don't think it gets a lot more complicated than that.

If you haven't already, I encourage you to participate in the discussion on Meta. No one at the Foundation imagines the global ban policy as a tool for the large projects to throw their weight around. I'm really pleased to see some Wikiversity folks editing the policy already.

Thanks, Steven (WMF) 23:09, 15 November 2011 (UTC)

Comment from Gravitoweak
Nobody can be banned globally. It's like saying "you are unwanted on a wiki, so we will not want you anywhere else". Yeah right, try globally banning Spanish User Esteban, English User Stephen, French User Etienne, when they're all the same dude at the keyboard. Whack a mole games for all! Gravitoweak 01:00, 20 November 2011 (UTC)

Comments from KYPark
It may be noteworthy that the global ban in a way is an analogy to such terrorism as scapegoating, Inquisition, excommunication, and even Japanese  ijime(いじめ) and Korean wangtta(왕따), and perhaps so on, and that it could be abused as likely as historically by degenerating into a radical partial tool of banning the liberal global standard, as it were, and thus desroying the global balance of yin and yang. As far as this fear is reasonable, may I wish Wikiversity's custodians to do their best to keep the global ban from abuses and misuses? KYPark [T] 07:25, 22 November 2011 (UTC)

Comments from Ebe123
No custodian should be having anything to do with global bans. If anyone sees a sock, report it on meta. I also agree with Steven Walling. Ebe123 12:00, 25 November 2011 (UTC)

Comments from Katarighe
I also agree, but no custodian should be having anything to do with global bans. If anyone sees a sock, report it on meta and they do the rest. --Katarighe 21:57, 1 December 2011 (UTC)

Comments from Marcus Zerbini
Moved to Colloquium


text:
User:Bmart14/enes100/3rdEscher

[Link to team page.]

Give instructor top 3 project choice list
This 3rd project, It will just be mike chung and I working on the escher. My top chioces were

 * Escher

 * Tape purge

 * Boat

I decided to stick with the escher project because I want to perfect the waterfall and see it in action.

Write problem statement
Try to figure out a way to hide and contain the hose for the third floor of the waterfall so that it seems to be never ending.

Assign Task1
Work with mike to incorporate my part of the project (water hoses and tubs) and mikes part (hardware and divits)

Compare actual work done to Task1
I edited all of the errors in my water tank and hose and now will be moving on to something else while I am waiting for my partner to finish building.

Week1 Narrative
Since I am waiting for my partner to finish up both of the wood waterfalls, I have moved on from the water tanks and am now working on the Google Sketchup program to draw out the escher waterfall to push the project forward, help assist mike in dimensions to make it perfect, and easier for him to build.

Here are a few pictures of the progress I have made so far:

Week1 Peer Review
Go to each team mates weekly summary wiki page. Read their activities and narrative. Then go the associated discussion page. Say something positive on this page. Try some constructive criticism. Add your name and a signature ~ by entering four tildes in a row to create a time and date stamp. Create a new category if another team mate has already commented here.

Assign Task2
This weekend I will work on getting dimensions drawn up and I will send them over to Mike for him to use. I will just take screen shots and save them as JPEG's so they will be easy to post and transfer to my partner.

Compare actual work done to Task2
I screen captured all of the images of measurements and am going to post the images on week two narrative.

Week2 Narrative
Here are multiple photos of my measurements so mike can write down the measurements for future use on projects.

Week2 Peer Review
Go to each team mates weekly summary wiki page. Read their activities and narrative. Then go the associated discussion page. Say something positive on this page. Try some constructive criticism. Add your name and a signature ~ by entering four tildes in a row to create a time and date stamp. Create a new category if another team mate has already commented here.

Assign Task3
Send Mike Chung the pictures and then work on the next project called "Impossible Balls Illusion"

Compare actual work done to Task3
I sent mike an email with the dimensions and worked on the 3D drawings for the other illusions.

Week3 Narrative
Over the weekend and throughout the week i worked with Google-Sketchup and drew multiple drawings of different types of uphill ball illusions and also the escher never ending triangle.

Here are a few pictures of my drawings.

Week3 Peer Review
Go to each team mates weekly summary wiki page. Read their activities and narrative. Then go the associated discussion page. Say something positive on this page. Try some constructive criticism. Add your name and a signature ~ by entering four tildes in a row to create a time and date stamp. Create a new category if another team mate has already commented here.

Assign Task4
Get the 3D files uploaded onto google docs so that the uphill illusions can be visible to everyone in the class and so that they can reproduce the project that my group is working on.

Compare actual work done to Task4
I learned how to share my Google Sketch-up files to wikiversity so that everybody who downloads google sketch-up can click on my link and have the file to see and play around with.

Week4 Narrative
Here is the link to the google sketch-up for everyone to use and move around. Just click the link, Click download, you need google sketch-up to run.

https://docs.google.com/leaf?id=0B4jgWc3hQ6V1YzhlZmVhYjQtNzI2Ni00MDI5LTg0YjEtNTE5MDkwMmUwMGVj&hl=en_US

Week4 Peer Review
Go to each team mates weekly summary wiki page. Read their activities and narrative. Then go the associated discussion page. Say something positive on this page. Try some constructive criticism. Add your name and a signature ~ by entering four tildes in a row to create a time and date stamp. Create a new category if another team mate has already commented here.

Complete Project Page
Follow the "project done" format.

Start Next Project Week0 activities
During this week you will perform the week0 activities of the next project.

title: User:Bmart14/enes100/3rdEscher


text:
User:Egm6321.f11.team2/HW6

=R*6.1 - Solve Nonhomogeneous L2-ODE-CC =

Given
As an application of nonhomogeneous L2-ODE-CC:

2nd exactness condition for N2-ODES is:

For problem 2, integrating factor is

Find
1. Find the PDEs that governs the integrating factor $$\displaystyle h(x,y)$$ using 2nd exactness condition for N2-ODEs

2. Solve (6.1.1) using trial solution for integrating factor of $$\displaystyle h(t)={{e}^{\alpha t}}$$

2.1) Find $$ (\bar a_1,\bar a_0)$$ in terms of $$ (a_0,\ a_1,\ a_2) $$.

2.2) Find the quadratic equation for $$\displaystyle \alpha $$.

2.3) Reduced-order equation: lead to

$$\displaystyle e^{\alpha t}[\bar a_1y'+\bar a_0y]=\int e^{\alpha t}f(t)dt$$

$$\displaystyle \bar a_1y'+\bar a_0y=e^{-\alpha t}\int e^{\alpha t}f(t)dt$$

2.4) Use the IFM to solve the equation in part 2.3.

2.5) Show that

$$\displaystyle  \alpha \beta = \frac {a_0}{a_2}$$.

$$\displaystyle  \alpha+\beta=\frac{a_1}{a_2}$$

2.6) Deduce the particular solution $$\displaystyle y_P(t)$$ for general excitation $$\displaystyle f(t)$$

2.7) Verify result with table of particular solutions for

$$\displaystyle f(t) = t exp(bt) $$

2.8) Solve the nonhomogeneous L2-ODE-CC with the following excitation

Hyperbolic function: $$\displaystyle f(t) = tanh t $$

For the coefficients (a0,a1,a2),consider two characteristic equations:

2.8.1) $$\displaystyle (r+1)(r-2) = 0$$

2.8.2) $$\displaystyle (r-4)^2 = 0 $$

2.9) For each case in questions 2.8.1 and 2.8.2, determine the fundamental period of undamped free vibration, and plot the solution for the excitation for about 5 periods, assuming zero initial conditions.

Part 1
Multipling $$\displaystyle H(t,y)$$ in the both sides, (6.1.1) can be rewritten as follows:

In the 2nd exactness condition,

From (6.1.5) and (6.1.6), We can get the following relation:

Assuming that H(t,y) and F(t,y) are only the functions of t in (6.1.2) and (6.1.3), and P=y', we can get the following relations in the 2nd exactness condition:

From (6.1.9) and (6.1.10), we can get the following result:

Part 2.1
where $$ \bar{a}_2 = 0 $$

$$ \frac{d}{dt}\Big[e^{\alpha t}(\bar{a}_1y'+\bar{a}_0y) \Big] = e^{\alpha t}\Big(\bar{a}_1 y + (\alpha \bar{a}_1+\bar{a}_0)y' + \alpha \bar{a}_0 y \Big) = e^{\alpha t}\big[a_2y+a_1y'+a_0y\big] \! $$

Thus, we can the the following relation.

$$ \bar{a}_1 = a_2 \! $$

$$ \bar{a}_0 = a_1 - \alpha a_2 = a_0/\alpha \! $$

Part 2.2
Multiplying $$\displaystyle \alpha $$ in the both second and third sides of (6.1.9) and rewriting it, we can get the following quadratic equation.

Part 2.3
From Part 2.1,

The above function can be rewriten as follows:

where $$ \beta=\frac{\bar a_0}{\bar a_1}$$

Part 2.4
The integrating factor to use IFM is $$ \bar{h}(t) = exp \Big[ \int \underbrace{\frac{\bar{a}_0}{\bar{a}_1}}_{\beta} dt \Big] = e^{\beta t} \! $$

The IFM would be used for the solution as follows: $$\displaystyle y(t)=\frac{1}{\bar h(t)}\int^t \bar h(s)B(s)ds $$ The result of Part 2.3 will be devided by $$\displaystyle \bar a_1 $$ to obtain B(s). $$\displaystyle y'+\beta y = \frac{e^{-\alpha t}}{\bar a_1} \int e^{\alpha t}F(t)dt = B(s) $$ Then we can combine $$\displaystyle h(t), \ B(s) $$ into $$\displaystyle y(t) $$ to find

Part 2.5
$$ \beta = \frac{\bar{a}_0}{\bar{a}_1} = \frac{a_0/\alpha}{a_2} $$

Multiplying $$\displaystyle \alpha $$ in the both first and last sides of the above equation, we can get the following:

$$ \alpha\beta = \frac{a_0}{a_2} $$

$$ \beta = \frac{\bar{a}_0}{\bar{a}_1} = \frac{a_1 - \alpha a_2}{a_2} = \frac{a_1}{a_2} - \alpha $$

Thus, $$ \alpha + \beta = \frac{a_1}{a_2} $$

Part 2.6
When $$\displaystyle \alpha $$ and $$\displaystyle \beta $$ are the roots of the characteristic equation, the homogeneous solution is

The particular solution $$\displaystyle y_P(t) $$ is

Part 2.7
Since $$\displaystyle F(t) = t e^{bt} $$,

Part 2.8.1
Thus, the L2-ODE is given by

coefficients $$\displaystyle {{a}_{0}}$$, $$\displaystyle {{a}_{1}}$$, $$\displaystyle {{a}_{2}}$$ are

From the root of the above characteristic equations, we can see the following:

$$\displaystyle \alpha=-1, \beta=2$$

The excitation is hyperbolic function as follows: $$\displaystyle f(t)=tanh(t)$$

With the website of "wolframalpha", the general solution y(t) is $$\displaystyle y(t)=\frac{1}{6}\left[1+2e^{-2t}log(e^{2t}+1)-4e^ttan^{-1}(e^{-t})\right]$$

Part 2.8.2
Thus, the L2-ODE is given by

The coefficients $$\displaystyle {{a}_{0}}$$, $$\displaystyle {{a}_{1}}$$, $$\displaystyle {{a}_{2}}$$ are

From the root of the above characteristic equations, we can see the following:

$$\displaystyle \alpha=\beta=4$$

The excitation is hyperbolic function as follows: $$\displaystyle f(t)=tanh(t)$$

With the website of "wolframalpha", the general solution y(t) is $$\displaystyle y(t)=-\frac{Li_2(-e^{2t}\cdot e^{-4t})}{2}-\frac{e^{-2t}}{2}+\frac{1}{16}$$

=R*6.2 - Showing that the form of particular solution in notes agree with the one in book by King and others =

Given
And

Find
with

Solution
From equation Equation 6.2.2 Substituting the value of Wronskian in the above equation Substituting the value of 'h(x)' from Equation 6.2.5 into Equation 6.2.1 Integrating the above Equation by parts and simplifying: Applying dummy integrals: Multiplying the terms inside bracket by $$\displaystyle u_1(x) $$ Taking $$\displaystyle u_1(x) \,\, u_2(x)$$ inside integral. Combining the two integrals:

=R*6.3 - Invalid Roots of a Characteristic Equation=

Given
The L2-ODE-VC: $$\displaystyle (x - 1) y'' - x y' + y = 0 $$(0) Using the Trial Solution $$\displaystyle y = e^{r x}$$ If it is assumed that r is a constant, the characteristic equation is $$\displaystyle (x-1) r^2 - x r + 1 = 0$$

Find
It can be seen that the roots of the characteristic equation are, $$\displaystyle r_1 = 1$$ $$\displaystyle r_2(x) = \frac{1}{x - 1}$$ Explain why $$\displaystyle r_2(x)$$ is not a valid root, i.e., $$\displaystyle u_2(x) = e^{x r_2(x)}$$ is not a valid solution.

Solution
$$\displaystyle r_2(x)$$ is not a valid root because it is assumed for the trial solution r is a constant, thus r cannot be a function of x. To see this more clearly we can assume that r is a function of x and see what the result would be. This would make the trial solution $$\displaystyle y = e^{x r(x)}$$ Using this trial solution it can be seen that a different characteristic equation is obtained. $$\displaystyle y' = (r(x) x )' e^{x r(x)}$$ $$\displaystyle y = (r(x) x ) e^{x r(x)} + ((r(x) x )')^2 e^{x r(x)}$$ $$\displaystyle (x - 1) ((r(x) x )'' + ((r(x) x )')^2) - x ((r(x) x )') + 1 = 0$$ It can be seen that this characteristic equation is not the same as the characteristic equation obtained by assuming r is a constant. This shows that $$r_2(x)$$ is not a valid root.

R*6.4 – Using the Method of Variation of Parameters to Find a Linearly Independent Solution to a Homogeneous L2-ODE When One Solution is Known

Given
$$\displaystyle u_1 := e^x$$

$$\displaystyle F(u_1) = 0$$

Find
Using u1 and the method of Variation of Parameters, determine another, linearly independent solution of 6.4.1.

Solution
Let

$$\displaystyle u = m(x)\,u_1 = m(x)\,e^x$$

Then

$$ \begin{align} u' &= m'\,e^x + m\,e^x \\ u &= m\,e^x + 2m'\,e^x + m\,e^x \end{align} $$

Substituting these values into 6.4.1, we find

$$ \begin{align} F(u) &= (x-1)\,( m''e^x + 2m'e^x + m\,e^x ) - x\,( m'e^x + m\,e^x ) + m\,e^x \\ &= \left[ (x-1) \right] m''e^x + \left[2(x-1) - x \right] m'e^x + \cancel{\left[ (x-1) - (x-1) \right]}\, m\,e^x \\ &= \left[ (x-1)\,m'' + (x-2)\,m' \right]\,e^x \\ &= 0 \end{align} $$

For this to be true for all x, the expression in brackets must be equal to zero. This gives us a differential equation for m:

$$\displaystyle (x-2)\,m' + (x-1)\,m'' = 0$$

Since m does not appear in this equation, we may reduce its order by defining p := m'.

As noted above, 6.4.2 is in the particular form for an N1-ODE, but it is not exact since

$$\displaystyle M_p = x-2 \quad\neq\quad 1 = N_x$$

Using the IFM and assuming hp = 0 yields

$$ \begin{align} \frac{h_x}{h} &= \frac{1}{N}\,(M_p - N_x) \\ \frac{h_x}{h} &= \left(\frac{1}{x-1}\right)(x-3) \\ \int \frac{dh}{h} &= \int \frac{x-3}{x-1}\,dx \\ \log h &= x - 2\log (x-1) \\ \log h + \log (x-1)^2 &= x \\ \log (h\,(x-1)^2) &= x \\ h &= \frac{e^x}{(x-1)^2} \\ \end{align} $$

We see that our assumption about hp holds. Multiplying 6.4.2 through by h gives

$$ \begin{align} \frac{e^x\,p'}{x-1} + \frac{x-2}{(x-1)^2}\,e^x\,p &= 0 \\ \frac{d}{dx} \left( \frac{e^x\,p}{x-1}\right) &= 0 \\ \frac{e^x\,p}{x-1} &= k_1 \\ p &= k_1\,(x-1)e^{-x} \end{align} $$

Since p := m', we may integrate the expression above to determine m:

$$\displaystyle m(x) = -k_1\, x e^{-x} + k_2$$

Finally, substituting this expression for m into the definition of u := m ex we arrive at

$$\displaystyle u(x) = k_2\, e^x + k_3\, x \qquad k_3 := -k_1$$

Since u is a solution of 6.4.1, and it is a linear combination of u1 and x, we finally conclude that the other homogeneous solution of 6.4.1 is

$$\displaystyle u_2 = x $$

=R*6.5 - Find two homogeneous solutions =

Given
$$\displaystyle (x+1)y''-(2x+3)y' + 2y = 0 $$(6.5.1) $$\displaystyle y = e^{rx} $$(6.5.2)

Find
Find $$\displaystyle u_1(x), u_2(x) $$ of eq 6.5.1 using the trial solution eq 6.5.2

Solution
$$\displaystyle y = e^{rx} \,\,\,\, y' = re^{rx} \,\,\, y'' = r^2e^{rx} \,\,\, $$(6.5.3) plugging eq 6.5.3 into eq 6.5.1 $$\displaystyle (x+1)r^2e^{rx}-(2x+3)re^{rx}+2e^{rx} = 0 $$ $$\displaystyle (x+1)r^2 - (2x + 3)r + 2 = 0 $$ $$\displaystyle r = \frac {(2x+3) \pm \sqrt{(2x+3)^2-8(x+1)}}{2(x+1)} $$ $$\displaystyle r = \frac{(2x+3) \pm (2x+1)}{2(x+1)} $$ $$\displaystyle r_1 = 2, \,\,\,\,r_2 = \frac{(2x+3)-2x - 1 }{2(x+1)} $$ Now we can find u(x), that is $$\displaystyle u_1(x)= e^{2x} $$ From lecture note 34-5, $$\displaystyle u_2(x)= u_1(x) \cdot \int \frac{1}{u_1^2(x)}exp[-\int a_1(x)dx]dx $$ $$\displaystyle a_1(x) = \frac {-(2x+3)}{x+1}$$ $$\displaystyle u_2(x) = e^{2x} \cdot \int{ e^{-4x}\cdot e^{\int \frac{2x+3}{x+1}dx}dx} $$ $$\displaystyle u_2(x) = e^{2x}\cdot \int{ e^{-4x}\cdot e^{(2x + log (x+1))}dx}$$ $$\displaystyle u_2(x) = e^{2x}\cdot \int{ e^{-4x}\cdot e^{2x} \cdot (x+1)dx}$$ $$\displaystyle u_2(x) = e^{2x}\cdot \int{ e^{-2x}\cdot (x+1)dx}$$ $$\displaystyle u_2(x) = e^{2x}\cdot e^{-2x}\cdot \frac {-(2x+3)}{4}$$ $$\displaystyle u_2(x) = \frac {-(2x+3)}{4} $$ Here -1/4 is constant. Thus, homogeneous solution is that $$\displaystyle y(x) = c_1\cdot e^{2x} + c_2\cdot (2x+3) $$

=R*6.6 - Finding L2-ODE-VC =

Given
Trial solution

$$\displaystyle y(x) = \frac {e^{rx}}{\sin x}$$ (6.6.1)

and characteristic equation.

$$\displaystyle (r-2)(r-\frac {1}{1+x})=0$$ (6.6.2)

Find
Find an L2-ODE-VC whose characteristic equation is 6.6.2

Solution
From 6.6.1, we have

$$\displaystyle y'= \frac{r\,{e}^{r\,x}}{\mathrm{sin}\left( x\right) }-\frac{{e}^{r\,x}\,\mathrm{cos}\left( x\right) }{{\mathrm{sin}\left( x\right) }^{2}}$$ (6.6.3)

$$\displaystyle y''= \frac{{r}^{2}\,{e}^{r\,x}}{\mathrm{sin}\left( x\right) }+\frac{{e}^{r\,x}}{\mathrm{sin}\left( x\right) }-\frac{2\,r\,{e}^{r\,x}\,\mathrm{cos}\left( x\right) }{{\mathrm{sin}\left( x\right) }^{2}}+\frac{2\,{e}^{r\,x}\,{\mathrm{cos}\left( x\right) }^{2}}{{\mathrm{sin}\left( x\right) }^{3}}$$ (6.6.4) then

$$\displaystyle y'=\left(r-\frac{\,\mathrm{cos}\left(x\right)}{\mathrm{sin}\left(x\right)}\right)\frac{{e}^{r\, x}}{\mathrm{sin}\left(x\right)}$$ (6.6.5)

$$\displaystyle y''=\left({r}^{2}+1-\frac{2\, r\,\mathrm{cos}\left(x\right)}{\mathrm{sin}\left(x\right)}+\frac{2\,{\mathrm{cos}\left(x\right)}^{2}}{{\mathrm{sin}\left(x\right)}^{2}}\right)\frac{{e}^{r\, x}}{\mathrm{sin}\left(x\right)}$$ (6.6.6) So we can assume that

$$\displaystyle a_{2}(x)\left({r}^{2}+1-\frac{2\, r\,\mathrm{cos}\left(x\right)}{\mathrm{sin}\left(x\right)}+\frac{2\,{\mathrm{cos}\left(x\right)}^{2}}{{\mathrm{sin}\left(x\right)}^{2}}\right)\frac{{e}^{r\, x}}{\mathrm{sin}\left(x\right)}+a_{1}(x)\left(r-\frac{\,\mathrm{cos}\left(x\right)}{\mathrm{sin}\left(x\right)}\right)\frac{{e}^{r\, x}}{\mathrm{sin}\left(x\right)}+a_{0}(x)\frac{{e}^{r\, x}}{\mathrm{sin}\left(x\right)}=0$$ (6.6.7)

$$\displaystyle a_{2}(x){r}^{2}+\left(a_{1}(x)-a_{2}(x)\frac{2\,\mathrm{cos}\left(x\right)}{\mathrm{sin}\left(x\right)}\right)r-a_{1}(x)\frac{cos\left(x\right)}{\mathrm{sin}\left(x\right)}+a_{2}(x)+a_{2}(x)\frac{2\,{\mathrm{cos}\left(x\right)}^{2}}{{\mathrm{sin}\left(x\right)}^{2}}+a_{0}(x)=0$$ (6.6.8) comparing 6.6.8 with the 6.6.2 we have

$$\displaystyle a_{2}=x+1$$ (6.6.9) $$\displaystyle a_{1}=2(x+1)\frac{\mathrm{cos}\left(x\right)}{\mathrm{sin}\left(x\right)}-(2x-3)$$ (6.6.10) $$\displaystyle a_{0}=1-x-(2x-3)\frac{\mathrm{cos}\left(x\right)}{\mathrm{sin}\left(x\right)}$$ (6.6.11) Thus

$$\displaystyle \left(x+1\right)y''+\left(2(x+1)\frac{\mathrm{cos}\left(x\right)}{\mathrm{sin}\left(x\right)}-(2x-3)\right)y'+\left(1-x-(2x-3)\frac{\mathrm{cos}\left(x\right)}{\mathrm{sin}\left(x\right)}\right)y=0$$ (6.6.12)

=R*6.7 - Homogeneous Solution of Legendre Function Using Variation of parameters=

Given
The general form of the Legendre Equation is

$$\displaystyle P_2(x)$$ should be

for the following result of $$\displaystyle Q_2(x)$$

Find
Show

using the Method of Variation of Parameters.

Solution
When n=2, the given Legendre Equation is as

(6.7.4) cam be rewritten as follows:

Let $$\displaystyle y(x) = U(x)\cdot {u}_{1}(x)$$ and $$\displaystyle P_2(x) = {u}_{1}(x)$$.

where $$\displaystyle \begin{align} &y = U {u}_{1} \\ &y' = U {u}_{1}'+U' {u}_{1} \\ &y= U {u}_{1}+2U' {u}_{1}'+U'' {u}_{1} \\ \end{align} $$

To reduce the order of (6.7.6), $$\displaystyle Z:=U'$$ willb be used.

To use integrating factor method, we first need to find the integrating factor, h(x), as follows:

The soloution of Z is

From the definition of Z(x)= U',

Solving y(x) with U(x),

2nd homogeneous solution is

Thus,

=R*6.8 - Solving L2-ODE-VC using variation of parameters. =

Given
and

Find
For both equations: 1) Find the first homogenous solution by trial solution. 2) Find the complete solution by variation of parameters with excitation $$ \displaystyle f(x)= exp(\alpha x) $$

Solution
Solving for homogenous solution of Equation 6.8.1 Consider the general trial solution $$ \displaystyle y=x^c e^{rx} $$ Taking derivative to obtain $$ \displaystyle y' $$ and $$ \displaystyle y'' $$ Substituting the derivatives back into equation 6.8.1
 * {| style="width:100%" border="0" align="left"

Solving the above Equation for constants 'r' and 'c' :
 * $$\Rightarrow x^{c+1}\left[r^2-r \right]+x^c\left[ 2rc-r^2-c+1 \right]+x^{c-1}\left[c^2-c-2rc \right]+x^{c-2}\left[c-c^2 \right]=0$$
 * }
 * }
 * }
 * }
 * {| style="width:100%" border="0" align="left"

\begin{array}{*{20}l} i) & c=0 & r=1\\  ii) & c=1 & r=0\\ \end{array} $$ Therefore First Homogeneous solution is
 * $$\displaystyle
 * $$\displaystyle
 * }
 * }

and second homogeneous solution is

Solution is a linear combination of two homogenous solutions: Now solving for complete solution if the forcing function $$ \displaystyle f(x)= e^{{\alpha} x }$$ Above equation can be rewritten as:

Now Therefore: Now Integrating factor is defined as: Therefore: Now particular solution is defined as : Now complete solution is defined as:

Solving for homogenous solution for Equation 6.8.2 Assuming the general trial solution $$ \displaystyle y=x^c e^{rx} $$ Taking derivative to obtain $$ \displaystyle y' $$ and $$ \displaystyle y'' $$ and substituting the values back into equation 6.8.2, we obtain: Solving the above Equation for constants 'r' and 'c' :
 * {| style="width:100%" border="0" align="left"

\begin{array}{*{20}l} i) & c=-1 & r=i\\  ii) & c=-1 & r=-i\\ \end{array} $$ Therefore First Homogeneous solution is
 * $$\displaystyle
 * $$\displaystyle
 * }
 * }

and second homogeneous solution is

Solution is a linear combination of two homogenous solutions: Now solving for complete solution if the forcing function $$ \displaystyle f(x)= e^{{\alpha} x }$$ Above equation can be rewritten as:

Now

Therefore: Now Integrating factor is defined as:

Therefore: Now particular solution is defined as :

Now complete solution is defined as:

.

=R6.9 - Using Variation of Parameters to Determine a Homogeneous Solution=

Given
$$\displaystyle ( 1 - x^2 ) y'' - 2 x y' + 2 y = f(x)$$(1) Where, $$\displaystyle f(x) = 1 $$(2) $$\displaystyle u_{1}(x) = P_1(x) = x$$(3)

Find
Given that equation (3) is the 1st homogeneous solution for the Non-homogeneous Legendre equation (L2-ODE-VC) in equation (1) find the solution $$\displaystyle y(x)$$ by variation of parameters.

Solution
Let us assume that the solution takes the form, $$\displaystyle y(x) = U(x) u_1(x)$$ Where $$\displaystyle U(x) $$ is an unknown factor to be determined. Then, $$\displaystyle \left [ y = U u_1 \right ] \times a_0(x)$$ $$\displaystyle \left [ y' = U u'_1 + U' u_1 \right ] \times a_1(x)$$ $$\displaystyle \left [ y = U u_1 + 2 U' u'_1 + U'' u_1 \right ] \times a_2(x)$$ $$\displaystyle a_0 y + a_1 y' + a_2 y = U \left [ a_0 u_1 + a_1 u'_1 + a_2 u_1 \right ] + U' \left [ a_1 u_1 + 2 a_2 u'_1 \right ] + a_2 U'' u_1 = f(x) $$ Since $$\displaystyle u_1(x) $$ is a homogeneous solution, $$\displaystyle a_0 u_1 + a_1 u'_1 + a_2 u''_1 = 0$$ Using a substitution of variables, $$\displaystyle Z:= U'$$ We obtain the equation, $$\displaystyle \tilde a_1(x) Z' + \tilde a_0(x) Z = \frac {f(x)}{a_2(x) u_1(x)}$$ Where, $$\displaystyle \tilde a_1(x) = 1$$ $$\displaystyle \tilde a_0(x) = \frac {a_1(x) u_1(x) + 2 a_2(x) u'_1(x)}{a_2(x) u_1(x)}$$ In order to solve for $$\displaystyle Z(x) $$ the integrating factor method can be used. Because all variables are a function of x we can assume that the integration factor is a function of x, thus $$\displaystyle h(x) = \exp \left [ \int \tilde a_0(x) dx \right ]$$ $$\displaystyle h(x) = \exp \left [ \int \frac {a_1(x)}{a_2(x)} + \frac {2 u'_1(x)}{u_1(x)} dx \right ]$$ $$\displaystyle h(x) = u^2_1(x) \exp \left [ \int \frac {a_1(x)}{a_2(x)} dx \right ]$$ $$\displaystyle Z(x) = \frac {1}{h(x)} \left [ k_2 + \int h(x) \frac {f(x)}{u_1(x)} dx \right ]$$ $$\displaystyle U(x) = k_1 + \int Z(x) dx$$ Substituting in all of the variables we obtain the equation for the solution, $$\displaystyle y(x) = k_1 u_1(x) + u_1(x) \int \frac{1}{h(x)} \left [ k_2 + \int h(x) \frac{f(x)}{u_1(x)} dx \right ] dx$$ $$\displaystyle y(x) = k_1 u_1(x) + k_2 u_1(x) \int \frac{1}{h(x)} dx + u_1(x) \int \frac{1}{h(x)} \left [ \int h(x) \frac{f(x)}{u_1(x)} dx \right ] dx$$ $$\displaystyle y(x) = k_1 x + k_2 x \int \left [ \frac{1}{x^2} \exp \left [ - \int \frac{-2x}{1-x^2} dx \right ] \right ] dx + x \int \left [ \frac {1}{x^2} \exp \left [ - \int \frac{-2x}{1-x^2} dx \right ] \int \left [ x \exp \left [ \int \frac{-2x}{1-x^2} dx \right ] \right ] dx \right ] dx$$ $$\displaystyle y(x) = k_1 x + k_2 x \int \left [ \frac{1}{x^2 (1 - x^2 )} \right ] dx + x \int \left [ \frac {1}{x^2 ( 1 - x^2 ) } \int ( x (1 - x^2) ) dx \right ] dx$$ $$\displaystyle y(x) = k_1 x + k_2 \left [ \frac{x}{2} \log \left ( \frac {1+x}{1-x} \right ) - 1 \right ] + x \int \left [ \frac {1}{x^2 ( 1 - x^2)} (\frac{1}{2} x^2 - \frac{1}{4} x^4) \right ] dx$$ $$\displaystyle y(x) = k_1 x + k_2 \left [ \frac{x}{2} \log \left ( \frac {1+x}{1-x} \right ) - 1 \right ] + x \int \left [ \frac {2 - x^2}{4(1 - x^2)} \right ] dx$$ $$\displaystyle y(x) = k_1 x + k_2 \left [ \frac{x}{2} \log \left ( \frac {1+x}{1-x} \right ) - 1 \right ] + \frac {x}{8} \left [ 2 x + \log \left ( \frac {x+1}{1-x} \right ) \right ] $$ Where the second homogeneous solution is, $$\displaystyle y(x) = \frac{x}{2} \log \left ( \frac {1+x}{1-x} \right ) - 1$$ And the particular solution is, $$\displaystyle y(x) = \frac {x}{8} \left [ 2 x + \log \left ( \frac {x+1}{1-x} \right ) \right ] $$

=Contributing Members= Egm6321.f11.team2.kim I solved R*6.5 and proofread R*6.3, R*6.7, R*6.8 and R*6.9 Egm6321.f11.team2.johri.y 19:15, 16 November 2011 (UTC) I solved problem R*6.2 and R*6.8. Egm6321.f11.team2.Xia I solved R*6.6 and proofread R*6.4 [User:Egm6321.f11.team2.kim|Egm6321.f11.team2.kim]] I solved R*6.5 and proofread R*6.3, R*6.7, R*6.8 and R*6.9 Egm6321.f11.team2.epps 20:21, 16 November 2011 (UTC) I solved R*6.4 and proofread R6.2, R6.3, R6.5, R6.6, and R6.7.

Egm6321.f11.team2.rho21:49, 16 November 2011 (UTC) I solved R*6.1 and R*6.7 and proofread R6.4, R6.5, R6.8, and R6.9. Egm6321.f11.team2.wise 21:57, 16 November 2011 (UTC) I solved R*6.3 and R6.9 and proofread R6.7, and R6.8

title: User:Egm6321.f11.team2/HW6


text:
Schools/Lugansk state medical university

|name             = Lugansk State Medical University - LSMU |native_name      = Луганський державний медичний університет |established      = 1956 |rector           = Professor Ivchenko Valery Constantinovich |city             = Lugansk |state            = Lugansk |province         = |country          = Ukraine |nickname         = LSMU EDU |website          = lsmuedu.com |facebook page    = Lugansk State Medical University |email            = [info@lsmuedu.com] }}

Lugansk State Medical University is a high educational establishment of the fourth level of accreditation in the city of Lugansk (Ukraine). It was founded on May 6, 1956. At the present the university is a powerful scientific educational and treatment complex including medical biologic lyceum, gymnasium, distant educational facilities and six faculties. More than 3000 students study at the university, citizens from more than 60 countries are among them. The faculties include 40 chairs, 22 clinical and 18 theoretical ones. One can get post-graduation education at the faculty of post-graduate education, where 4 chairs work. Diploma training is based on modern methods and studying techniques introduction. 400 lecturers including 76 doctors of science, professors, 288 candidates of science and associate professors, 9 Honored Science and Technique Workers of Ukraine, one Honored Worker of Public Education of Ukraine, 5 laureates of The State Prize of Ukraine, 2 experts of the State Attestation Commission of the Ministry of Public Health of Ukraine work at the university. There are three studying buildings, “the Book Palace”, a chemistry-studio, a dental clinic, a gym, as well as some chairs and clinics in the city medical establishments. The university confidently possesses one of the leading places among the medical educational establishments of Ukraine: more than 87% of its lecturers have scientific degrees. The two leading university’s scientific problem tasks are the scientific elaboration and introduction of medical life support of casualties in androgenic catastrophes and medical aspects of ecology in Donbass industrial region conditions. The work over the former task has become the basis for theory and practice of medicine of catastrophes in Ukraine. This work was awarded the State Prize of Ukraine in the Field of Science and Technique in 2000. Scientific and pedagogical staff is systematically trained. 3 or 4 doctor's and 23-25 candidate's theses are defended annually in different specialities. . Two Specialized Scientific Councils for theses defences work successfully at the University. Our University has been publishing scientific journals and collections of articles, which are acknowledged by the НАС of Ukraine.

History
The university was founded in 1956 according to the USSR Council of Ministers Directive dated May 6, 1956. then it was called Voroshilovgrad state medical university. The first acting rector was the head doc tor of the regional hospital, the Honored doctor of Ukraine I. D. Vashenko. His successor became E. G. Palchevsky. He headed the university from February 25, 1957 till May 25, 1960, Doctor of Medicine. Under his supervision the lecturers and the students of the university conducted the first scientific research, the Academic council and the Students’ scientific society were also created. F. M. Povelitsa, Candidate of science, associate professor, was the rector in 1960-1963. He paid great attention to the development of clinical base of the university. During the period of 1963–1966 the university was headed by D.G. Kortchikov, Candidate of science, associate professor. He finished the creation of scientific and clinical foundations of the university. In the years 1967 – 1975 the rector of the university was I. I. Tchaikovska, Candidate of science, professor. Specialized academic council was created due to her efforts; the administrative building and two students’ hostels were also built at that time. Training and educational work was advanced. Coal extractive industry workers’ health protection had become one of the university leading scientific problem tasks. A.M. Fadeev, Candidate of science, associate professor, headed the university from 1975 till 1984. A new studying building, a hostel and a gym were built. Two new faculties (postgraduate and pediatric) started working. In 1983 the first foreign citizens came to study to the university. Immunology had become a new actual scientific problem task: a profile chair and some laboratories were created. In 1984 - 2003 the university was headed by V.G. Koveshnicov, M.D., professor. During the years of his direction he re-organized the administrative teaching body, students’ hostels, university’s dental clinic, the library, the gym and the stadium. The faculties of dentistry, pharmacy and nursing were opened. The university has gained the recognition abroad. In 2003 the rector of the university became V.K. Ivchenko, M.D., professor. He prepared the university for teaching in English. He has been developing such directions as educational activity of the university, students’.

Campus
Luhansk State Medical University has five buildings for theoretical classes and a wide net of clinical bases of medical institutions of Luhansk, which are equipped at the level corresponding to world standards. Today Luhansk State Medical University is a complex of buildings designed for practical classes, lectures, laboratory studies, library, research work and auxiliary services, covering. The total area owned by the Luhansk state medical University is 70466 sq.m: within it the area of study and laboratory premises is 33598 sq. mts. The teaching area per one student is 15 sq.m. Other clinical bases used by the Luhansk state medical University are administered by the Government healthcare department.

Organization and administration
400 teachers, among them 63 doctors of sciences, 273 candidates of sciences, including five Honored Science and Technique Workers of Ukraine, one Honored Worker of public education of Ukraine, two Honored doctors of Ukraine, two Laureates of State prize of Ukraine carry out pedagogical, scientific, medical and educational work at 48 departments.

Academics
Luhansk State Medical University is attested according to the highest (the fourth) Level of accreditation. The University activities conform with The Constitution of Ukraine, Ukrainian legislation, acts issued by the President and the Cabinet of Ministers of Ukraine, Decrees of the Health Department and Education Department of Ukraine, the University Rules. Luhansk State Medical University prepares specialists in 172 medical specialties. Organization of the medical process and methods of teaching at Luhansk State Medical University are built according to modern demands and world experience. The Luhansk State Medical University has introduced the conception of continuous medical education that in all parameters corresponds to all world standards, giving an opportunity to get qualification of different professional levels from Bachelor to Doctor of medicine.

The Luhansk State Medical University activities cover a wide range of subjects, all aimed at shaping a global University policy.


text:
Application of Integration by Parts

Application of integration by parts
$$ \int f(x)g'(x)\, dx = f(x)g(x) - \int f'(x)g(x)\, dx $$

Example 1
To Find $$ \int x e^x\, dx   $$

Let
 * $$ f(x) = x $$ and   $$ g'(x) = e^x $$

then
 * $$ \int x e^x\, dx

= xe^x - \int  e^x\, dx =  xe^x - e^x = (x-1)e^x + C $$

Example 2
To Find $$ \int x^2 e^x\, dx   $$

Let
 * $$ f(x) = x^2 $$  and  $$ g'(x) = e^x $$

then
 * $$ \int x^2 e^x\, dx = x^2e^x - 2\int xe^x \, dx = x^2e^x - 2(x-1)e^x

= (x^2-2x+2)e^x +C $$

by using the result from example 1

Example 3
To find $$ \int x^5n e^2x\, dx $$

here n is an integer

By mathematical induction and using the above two examples

 * $$ \int x^n e^x\, dx =  (x^n - {n}x^{n-1} + n(n-1)x^{n-2} -n(n-1)(n-2)x^{n-3} +... +(-1)^{n}n!)e^x + C $$

Anish27 23:28, 10 November 2011 (UTC)

title: Application of Integration by Parts


title: File:Pea1.f11.mtg37.djvu


title: File:Pea1.f11.mtg38.djvu


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User:鈴木裕久

http://www.hm7.aitai.ne.jp/~dynatech/

title: User:鈴木裕久


text: File:AFT new.svg

title: File:AFT new.svg


text: File:AFT 1.svg

title: File:AFT 1.svg


text: File:Drawing 1.svg

title: File:Drawing 1.svg


text: File:AFT 2.svg

title: File:AFT 2.svg


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Category:Walsh permutation

Articles: Walsh permutation, 3-bit Walsh permutation

Styles:
 * 3-bit Walsh permutation/style.css for the page 3-bit Walsh permutation

title: Category:Walsh permutation


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User:Inmookchung27/escher3

[Link Back To Team PAge]

Give instructor top 3 project choice list
I will continue to work on the escher project.

-Escher

-Tape purger

-robot arm

Write problem statement
The problem for this project third time around is how i am going to build the waterfall so that the water pumps are not seen but still creates the illusion.

Assign Task1
document measurements, and drill hole at the end of the first floor, and cut out divits against the poles. Also put pictures up

Compare actual work done to Task1
did not get to write down measurements,Also i put up pictures.

Week1 Narrative
After working on the Escher, it would be smart to write down the measurements before you start building. Since i built it from scratch, the illusion is quite not there. This week i tried a new waterfall design with 3 floors instead of 2 floors. We are working on Google sketch to get the specific measurements for the waterfall. Afterwards i can separate the pieces and get the exact measurements of them.

http://www.youtube.com/watch?v=jpcIIa2hKRo&feature=related

Week1 Peer Review
Go to each team mates weekly summary wiki page. Read their activities and narrative. Then go the associated discussion page. Say something positive on this page. Try some constructive criticism. Add your name and a signature ~ by entering four tildes in a row to create a time and date stamp. Create a new category if another team mate has already commented here.

Assign Task2
finally put the tubes and waterfall together, put up more pictures. try to get the measurements of the pieces.

Compare actual work done to Task2
didnt get to upload pictures. Definately will put up more pictures this weekend. ALso ask bryan for measurements and start on the other escher project.

Week2 Narrative
http://www.youtube.com/watch?v=vmkaVoLoFEU&feature=related

Week2 Peer Review
Go to each team mates weekly summary wiki page. Read their activities and narrative. Then go the associated discussion page. Say something positive on this page. Try some constructive criticism. Add your name and a signature ~ by entering four tildes in a row to create a time and date stamp. Create a new category if another team mate has already commented here.

Assign Task3
take down the measurements from google sketch and also start looking at other escher projects

Compare actual work done to Task3
took down the measurements, found a new escher project; ball illusion

Week3 Peer Review
Go to each team mates weekly summary wiki page. Read their activities and narrative. Then go the associated discussion page. Say something positive on this page. Try some constructive criticism. Add your name and a signature ~ by entering four tildes in a row to create a time and date stamp. Create a new category if another team mate has already commented here.

Assign Task4
get the project stable and get the measurements down for the new project.

Compare actual work done to Task4
got the measurements and wrote them down, also tested out many materials to see which material would stablize the project the best.

Week4 Peer Review
Go to each team mates weekly summary wiki page. Read their activities and narrative. Then go the associated discussion page. Say something positive on this page. Try some constructive criticism. Add your name and a signature ~ by entering four tildes in a row to create a time and date stamp. Create a new category if another team mate has already commented here.

Complete Project Page
Follow the "project done" format.

Start Next Project Week0 activities
During this week you will perform the week0 activities of the next project.

Week4 Narrative
File:Ball1.jpg|picture of ball...poles are too skinny, not stable enough. File:A119 endless-staircase.jpg|Caption2 File:Ballone.jpg| lighter material of wood so it does not fall over all the time File:Ball 2.jpg|Caption2

title: User:Inmookchung27/escher3


text:
Engineering Projects/Engines/Howard Community College/Fall2011/550/qjb-eng

Problem Statement
Design and construct a Sterling Engine.

Team Members

 * Lloyd
 * chi

 * Mirza

Summary
The team goal was to design and develop three separate working models of a Sterling engine. Utilizing nothing more than common items found inexpensively at any hardware store.

Overcoming the typical problems associated with this type of build would include the fitting of non-machined parts. Also typical is the using materials that are re-purposed and may not be the standard by which harmonics of any typical rotational design are cut from.

The primary means by which the mechanical system will be balanced will be the use of a flywheel. Critical to the systems function it must be proportionate to the system.

Weekly Reports

Poster

Story
Three students designed and built three versions of the Sterling engine with the notion that different approaches would be taken. All are vertical designs but with different materials and approaches.

This would provide a way to gain the perspective of the different methods of construction. At the same time this approach would provide an opportunity of encountering different setbacks associated with each design thus providing more sources to problem solve as a collective.

Decision List
Decided to construct three different designs

Material List
Materials list

Software List
Google+

Google Docs

Google Sketch-Up

Time
Hours Work Spreadsheet

Critical Measurements
Displacer Thickness= ½ displacement of displacer cylinder

Crankshaft Drive Offset= Equal to Length of Drive Stroke

Crankshaft Displacer Offset= (⅛-Length of Displacer Stroke)/ 2

Next Steps
Research the science prior to developing a design. Biggest mistake would to rush the design process by an eagerness to build.

Ideas for design:

Paint Can Model


text:
Book Reviews/The demographic black hole in the European Union

THE DEMOGRAPHIC BLACK HOLE IN THE EUROPEAN UNION

Aaron W. Andreason Department of Management and Marketing School of Business Administration University of Montana

Douglas R. Miller Washington State University Dept. of Management and Operations

Abstract
Low fertility rates in EU countries since the 1960s are bringing about a number of economic and social consequences which will have a negative impact on productivity, economic growth, social-welfare programs, patterns of immigration, Europe's ability to pull its weight diplomatically, culturally and militarily in the 21st century; and the very survival of the EU itself. Because of the current network of global trade and financial linkages international business and world prosperity could also be significantly impacted. Whether or not the worst of these consequences occur, however, depends upon the actions governments take and how they are able to manage the factors that limit needed solutions. The conclusion to this study is that no single policy intervention will resolve the situation and that governments need to move quickly and aggressively on several fronts in order to avoid the demographic and economic collapse of the EU itself.


text:
User:Jeffreycarllloyd/enes100/engine

Link to team page qjb-eng

Problem statement
Construct a Sterling Engine with common materials.

Week0 Activities
-Researched the fundamentals of the Sterling Engine -Confirmed which type of Sterling Engine to concentrate on

-Construction materials list:

 * 2-gallon sized paint cans
 * 1-quart sized paint can
 * 1-1/2" thick piece of UHMW(reduces friction)
 * 2-1/16" x 3" Music wire (connector rods)
 * 1-Coat hanger (crankshaft)
 * 1-Vinyl glove (vacuum seal)
 * 1-Film canister (drive cylinder)
 * 1-7/16" Threaded short pipe nipple w/ nut (hollow anchor for drive cylinder, allows for air flow)
 * 1-3/16" Foam poster board (displacer)
 * RTV Silicone
 * Epoxy glue

-Specialized tool list:

 * Heat gun (for vacuum forming vinyl for drive cylinder)
 * Sheet metal nibbler (cleanly cuts sheet metal without distorting edge)

Assign Task1
-Create a computer model of the design structure of the engine

-Begin layout and construction

Task 1 Assessment

 * Began construction of a paint bucket version.
 * Started Computer Model

Week 1 Activities
I went with a design that utilizes two gallon size paint cans as the displacer cylinder and the support structure. It is a low output version (low rpm, but gives a good idea of the design of a basic Sterling engine.

1st Draft Computer Model (to view must click download in the upper right)

I began construction of the Sterling Engine. I have finished the displacer cylinder, the displacer, and the the drive cylinder. The displacer was constructed with a 3/16 piece of poster board, cut with a 1/8 inch clearance for the radius.

Sterling Engine Week 1 photos

In order to construct the drive cylinder I had to thermal-vacuum the valve (vinyl glove). I used a vacuum attached to a base.It took several attempts due to overheating the vinyl, thus distorting the valve beyond what was acceptable.

| Thermal-vacuum form

I was able to make a solid valve after several attempts.

I used this tutorial and it was very helpful thus far. Paint Can Sterling engine.

Materials list

Task 2 Assignment

 * Complete drive shaft assembly
 * Attempt a test run

Task 2 Assessment

 * Drive shaft was completed
 * Tested system for proper vacuum

Week 2 Activities
Link to Week 2 Photos

Updated Materials list

Started with the Drive Cylinder. Mounted it to the Displacer Cylinder lid by way of a threaded lamb bolt. I used this because of it is hollow and the bottom retaining nut was a low profile that would not interfere with the operation cycle. Before mounting I measured the travel of the Drive diaphragm to ensure there was no interference. As it turned out it was to long, therefore I had shorten it. I used a hacksaw and cut of from the bottom (end with the narrow nut). This in theory will lock the narrow nut in place by the way the cut disfigures the threads.

After mounting the Drive cylinder i tested to ensure that there was sufficient vacuum, or the system would not function properly.

Displacer Cylinder Testing

It performed well without the heat differential, but I did a heat test and it provided vacuum but the displacer did not cycle. Further evaluation will have to be performed as a complete system before I dissection will be rendered.

With the vacuum tested I concentrated on the linkage and crankshaft. My measurement were derived from the formula of displacement stroke is the displacement minus 1/8 dived by two, and the Drive was the displacent dived by 2 then again by 2.

On the crankshaft lobes I installed nylon sleeves to minimized friction. The idea behind this to "crimp" the followers/ linkage as a means to prevent lateral travel of the rods while it maintains the the connecting rods free travel during the cycle.

I started the construction of the crankshaft frame. Again I used the nylon sleeves a bushing/ guide bearing.

To reduce friction I devised a linkage system with re-purposed electric connectors.

Task 3 Assignment

 * Redo the crank shaft ( was not satisfied with the first one)
 * Mount Crankshaft frame
 * Construct and mount the flywheel

Task 3 Assessment

 * Concerns with the crankshaft led me to return to research.

Week 3
revisited research the design of crankshaft. Most tutorials offer little insight. Through discussion it was determine that the stroke of the displacer should 1/8" less the then the displacement dived by two. The question is the stroke of the drive cylinder.

The original tutorial stated that the stroke of the of the drive cylinder should be set at a 1/4" of travel(1/8" offset) and after a mock up it appeared to be insufficient. the total travel of the drive is 1". During discussion in class the it was determined that the 1/4" was insufficient.

During the mock ups the material set aside for the project was deemed to short so I need to acquire more material suitable for the crankshaft.

[http://www.youtube.com/watch?v=O3U4ShL5hkk&feature=player_embedded#! Original Design]

Task 4 Assignment

 * Work out problems with crankshaft

Task 4 Assessment

 * Developed ratio for crankshaft

Week 4
Worked on the team page created the spreadsheet for hours worked

Teams Spreadsheet

title: User:Jeffreycarllloyd/enes100/engine


text:
Engineering Projects/Engines/Howard Community College/Fall2011/550 qjb-eng Weekly Reports

Link to qjb-eng's Team page

Week 0
We researched the different approaches to the design of the Sterling engine. With that, was a assessment of the materials needed for each design. The feasibility of each design was limited to the availability of the resources. This would ultimately be a major decision factor of our approach.

Week 1
Started three separate Sterling engines with the notion that different approaches would be taken. All are vertical designs but with different materials and approaches.

This would provide a way to gain the perspective of the different methods of construction. At the same time this approach would provide an opportunity of encountering different setbacks associated with each design thus providing more sources to problem solve as a collective.

One approach is with the use of two paint cans. This version will use a vacuum valve as the main drive cylinder.It ill provide a example of the intricacies with using materials with more mass.

The second is that of a soda can version. This version will use a piston and piston sleeve

The third is is a low temperature version using a soup can.

Week 2
Made progress on "paint can" model. Developed linkage system and constructed and fitted the crankshaft, crankshaft mount, Drive Cylinder, and developed an linkage system. The crankshaft frame needs to mounted, and the fly wheel needs to be constructed and fitted. First run may be possible by next weekend.

All the materials for the other two Sterling engines was acquired and construction has began. So issues with friction developed but most of the problem was mitigated.

Week 3
Construction continued this week too and we happened to exchange some good idea in class. Concerning the way to minimize friction at the crankshaft, Lloyd suggested using a small pvc tube around the crankshaft itself instead of attaching the power pistons directly to it. This pvc was not too tight around the wire thus making turning easy. This was quite fun to do since there is quite a big difference in our designs. Two of us use power pistons while one person is using instead some rubber-like material. Thus we are exploiting more than one avenue for the same engine.


text:
User talk:Jeffreycarllloyd/enes100/engine

Week 0
10/10 .. week 0 grading 1sfoerster 23:40, 15 November 2011 (UTC)

Week 1

 * The videos you posted are awesome. Never knew a hand's heat could power an engine!! 12:27 21 November(UTC)

You did alot of work over this past week. Good job updating our team page and explaining how each person will create their own engines and the last week we will present the best engine to the class. Mbaig7172 20:36 20 November(UTC)

10/10/50 ... 1sfoerster 19:54, 21 November 2011 (UTC)

Week 2
Good work as well with you engine design. Could be nice if u would bring it to class so we all could look at it.November 28(UTC)

10/10/50 .. 1sfoerster 14:11, 28 November 2011 (UTC)

Week 3
Nice work on your engine design. Let me know how it works out because i had some doubts since that displacer was quite heavy.qchi 8:59 December 1(UTC)

Great job updating your team page. I want to implement some concepts/ideas you used to create the crankshaft.Mbaig7172 02:44, 5 December 2011 (UTC)9:42 PM December 4 2011

10/10/50 ... great job 1sfoerster 19:33, 5 December 2011 (UTC)

Week 4
Thanks for Working on the Team Page 10/10/10 ... 1sfoerster 17:13, 14 December 2011 (UTC) Mirza Baig 6:30 PM 13 December 2011


text:
User:KYPark/Etymology/bridegroom

bridegroom

 * etymonline
 * bridegroom -- O.E. brydguma "suitor," from bryd "bride" (see bride) + guma "man" (cf. O.N. gumi, O.H.G. gomo, cognate with L. homo "man;" see homo- (2)). Ending altered 16c. by folk etymology after groom "groom, boy, lad" (q.v.). Common Germanic compound (cf. O.S. brudigumo, O.N. bruðgumi, O.H.G. brutigomo, Ger. Bräutigam), except in Gothic, which used bruþsfaþs, lit. "bride's lord."
 * groom -- husband-to-be at a wedding, c.1600, short for bridegroom, in which the second element is O.E. guma "man."

 * Proto-Germanic
 * wikt: Appendix:Proto-Germanic/brūdigumô

groom

 * Etymology 1
 * 1604, short for bridegroom ("husband-to-be"), from Middle English brydgrome, bridegome ("bridegroom"), from Old English brȳdguma ("bridegroom"), from brȳd ("bride") + guma ("man, hero"), from Proto-Germanic *gumô ("man, person"), from Proto-Indo-European *dhg'həmo-, *dhg'homo-.
 * Germanic cognates include Icelandic gumi and Norwegian gume. Cognate to human from Proto-Indo-European via Latin homo.
 * Second element reanalyzed as groom, "attendant."

 * Noun
 * 1)  A man who is about to become or has recently become part of a married couple. Short form of bridegroom.
 * Etymology 2
 * From Middle English grom, grome ("man-child, boy, youth"), of uncertain origin. Apparently related to Middle Dutch grom ("boy"), Old Icelandic grómr, gromr ("man, manservant, boy"), Old French gromme ("manservant"), from the same Germanic root. Possibly from Old English *grōma, from Proto-Germanic *grōmô, related to *grōanan ("to grow"), though uncertain as *grōanan was used typically of plants; its secondary meaning being "to turn green".
 * Alternate etymology describes Middle English grom, grome as an alteration of gome ("man") with an intrusive r (also found in bridegroom, hoarse, cartridge, etc.), with the Middle Dutch and Old Icelandic cognates following similar variation of their respective forms.

 * Noun
 * 1) A person who cares for horses.

guma

 * Old English

 * Etymology
 * From Proto-Germanic *gumô, .... Germanic cognates include Old Saxon gumo, Old High German gumo, gomo, Old Norse gumi (Icelandic gumi and Norwegian gume) .... The Indo-European root is also the source of Latin homo ....

 * Noun
 * 1) (poetic) man, hero
 * Synonyms
 * beorn
 * Derived terms
 * gumcynn
 * Descendants
 * English: groom (from whence bridegroom)

beorn

 * Old English

 * Etymology
 * The original sense may have been a poetical comparison with a wild animal: it seems to be cognate with Old Norse bjǫrn ‘bear’ .... [from Proto-Germanic *berô.]

 * Noun
 * 1) (poetic) man, warrior
 * se beorn on waruþe scip gemette. (The man found a ship on the strand. -- Legend of St Andrew)
 * Synonyms
 * guma

bear

 * Etymology 1
 * Middle English bere, from Old English bera, from Proto-Germanic *berô (compare West Frisian bear, Dutch beer, German Bär, Danish bjørn).
 * This is generally taken to be from Proto-Indo-European *bhreu- (“shining, brown”) (compare Tocharian A parno, B perne (“radiant, luminous”), Lithuanian bė́ras (“brown”)), related to brown and beaver. [...]
 * Use of an epithet (“brown”) in Proto-Indo-European is presumably taboo avoidance; compare Russian medved (“bear”), literally “honey-eater”, and French renard (“fox”), from proper name Renard.

 * etymonline
 * O.E. bera "bear," from P.Gmc. *beron, lit. "the brown (one)" (cf. O.N. björn, M.Du. bere, Du. beer, O.H.G. bero, Ger. Bär), from PIE *bher- (3) "bright, brown" (see brown). Greek arktos and Latin ursus retain the PIE root word for "bear" (*rtko), but it is believed to have been ritually replaced in the northern branches because of hunters' taboo on names of wild animals (cf. the Irish equivalent "the good calf," Welsh "honey-pig," Lithuanian "the licker," Rus. medved "honey-eater"). Others connect the Germanic word with Latin ferus "wild," as if it meant "the wild animal (par excellence) of the northern woods."

Conclusion

 * The Old English guma and beorn may be literal synonyms for a bear prior to poetic synonyms or metaphors for a man, warrior, hero, or the like, regardless of groom "horse servant" aka marshal.

title: User:KYPark/Etymology/bridegroom


text:
Computer engineering

Computer engineering is the science of making computers and their parts. Computer engineers are always trying to make new parts smaller and better. Computer engineering is related to Electrical engineering and Computer science. If you study Computer engineering, you learn about the hardware and software of computers. You will learn circuit theory and electronic circuits, too.

Computer engineering is often compared to Computer science. Computer engineering is about computer hardware and some software. Computer science is about computer software only. Computer engineers study Computer engineering, but software engineers study Computer science.

Computer engineering is a difficult major in college, but computer engineers are needed. . Software engineering companies, telecommunications firms, designers of digital hardware, and many other companies hire Computer engineering majors right out of college and pay them well.

Computer engineering students learn about computers and computer related system design and development. The computer related systems are software systems, hardware systems and systems of software and hardware in combination.

Learning videos

 * Gadget Guts: Amazon Echo Dot (2nd Generation)

title: Computer engineering


text:
Wikipedia/Writing an article on Wikipedia

Editing Wikipedia can be both enjoyable and rewarding. Working with other contributors in a collaborative environment to produce high quality content that may be read by millions of people is an experience worth treasuring. That said, Wikipedia has been developing for many years both as a project and as a community. The result is a complex and organic mix of policies, guidelines, practices and procedures, all of which are essential to guide the development of the project, and which even the newest contributer is expected to understand. Fail to work within this complex set of rules, and the result may be much less than enjoyable and rewarding: you can quickly find yourself on the receiving end of an escalating series of warnings, culminating in having your account disabled and prevented from taking part.

The good news is that it is not that hard to work within the rules. It just takes a bit of effort to get to know them before you start contributing, and that is what this course aims to do. By working through this material you should find yourself in the position of knowing as much about how Wikipedia works (and how to work within Wikipedia) as many experienced contributors. Thus you will be well positioned to take advantage of the opportunities Wikipedia provides, and well warned as to how to avoid many of the pitfalls.

Objectives

 * Explain the major policies which guide Wikipedia content creation and user interaction
 * Give students the practical information required to allow them to create new articles and edit existing ones while meeting the expectations of the wider Wikipedia community

Syllabus

 * What is Wikipedia?
 * The history of Wikipedia
 * Types of user accounts
 * The language of Wikipedia
 * The other projects
 * Online assessment
 * The structure of Wikipedia
 * Article and discussion pages
 * Mainspace, Wikispace and Userspace
 * Noticeboards
 * Online assessment
 * The Five Pillars
 * What being an "encyclopaedia" means in relation to content (COI)
 * What "free content" means in terms of Wikipedia
 * Interacting with other editors
 * Ignoring rules
 * Online assessment
 * Verifiability
 * Why it matters
 * What constitutes a reliable source
 * How to reference material
 * Online assessment
 * The notability guidelines
 * Online assessment
 * Copyright and the use of non-free content
 * Online assessment
 * Biographies of living people
 * Online assessment
 * The deletion process
 * Speedy deletion
 * Prods
 * Deletion discussions
 * Deletion review
 * Online assessment
 * Enforcement
 * Blocks and bans
 * Protection
 * Appeals
 * When things go wrong: what to do when things aren't going quite to plan.
 * Dispute resolution
 * Sockpuppetry accusations
 * Edit warring
 * Online assessment


text:
User talk:Grabautoinsurance

Block
I have blocked this account from editing for an indefinite period in accordance for creating multiple advertising pages. If you believe this block is unjustified, you may contest the block by adding the text below. Sincerely, James -- Jtneill - Talk - c 11:17, 11 November 2011 (UTC)

title: User talk:Grabautoinsurance


text:
User:Sano

=My favorite links=

 * Mediawiki
 * Meta Wikimedia
 * Simple English Wikipedia
 * Species
 * Commons Wikimedia
 * Incubator Wikimedia
 * Wikibooks
 * Wikinews
 * Wikipedia
 * Wikisource
 * Wikiversity
 * Wiktionary

title: User:Sano


text:
Engineering Projects/Electric Cars/Howard Community College/Fall2011/550 ekart v.2

Problem Statement
How can we develop an efficient electrical system for the ekart?

Team Members

 * CR
 * PA

Summary
Weekly reports

Story
In this project we continued working on the electric cars project for a second time. We were hoping to complete a working product to be able to showcase it at HCC, but we were unable for multiple reasons. Overall, this project was fun because it was challenging and very didactic. Even though, the 2nd and faster version of the ekart was not completed in time, we hope to ignite interest on projects of this kind to future ENES100 students.

Week One

 * Received ESC from Kelly Controllers.
 * Began work on ESC system for ekart.
 * Tested 1.6HP DC motor.

Week Two

 * Continued work on ESC circuitry.
 * Mounted motor to ekart.
 * Attached motor to modified drive-train.
 * Mounted batteries on ekart.

Week Three

 * Connected final components of ESC circuit.
 * Set up a 36V power source.

Week Four

 * Completed ESC circuit and tested it.
 * Programmed ESC.

Decision List

 * Decided to sacrifice weight in order to get power (from 12V to 36V).
 * Decided to purchase programming interface to program ESC and achieve the best performance.
 * Decided to eliminate reversing to lower the difficulty of assembling the ESC circuit + costs.
 * Decided to paint ekart with black spray paint.

Material List
Google Docs link

Software List

 * Web browser (researching purposes)
 * Autodesk 123D for go-kart design
 * Google Sketch Up
 * Kelly controllers programming software

Time
Average of 5 hours every week for a total of 25 hours (including week zero).

Tutorials
Tutorial Presentation

Next Steps

 * Get more funding for a high-end ekart with excellent materials.
 * Get large support from HCC and encourage intercollegiate ekart competitions.