Potential Free FEM Workflow

CAD (probably not free)

NetGen convert .stl into file type readable by GMSH

GMSH

FEniCS scripted through python or Matlab

Python is really easy to install on Unix systems.  Please note that in the example instead of x, and y for the dirchelet boundary condition, x[0] and x[1] were used instead inorder to get program to work.

Post Processing: GMSH (again)

The real question is whether I will be able to script the whole process via python.  I think so (and whether it can do time dependent contact mechanics problems).

Updates incoming 🙂

Update 8/02/2016

I have found getfem++ to be rather buggy. That is the sample problems have errors on my machine. It is a shame, because getfem++ looked so dang nice. If I come back to it I will update again here.

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Potential Free FEM Workflow

Slip Systems

When talking about slip systems, the it is important to speak the language. There is a common way for defining crystallographic lines and planes within the unit cell.

Lines/Directions

Lines or directions are defined by two points.  The first point is the origin on the unit cell. Then the other end of the vector is projected onto the three axes measured by the unit cell dimensions.  The three indices are then reduced to the smallest possible integer values.  Finally the values are given in brackets [uwv]  Overbars are used to represent negative numbers so instead of [-100] we would write [100].  Unfortunately in wordpress in overline is a little bit annoying to use so I will sometimes use the less compact form with the negative in front.

Hexagonal crystals (like sapphire) use a four-axis (Miller-Bravis) coordinate system. The first three axes  are all on the x-y plane with 120 degree separation between them.  The fourth axis is the z-axis.

Planes

Although planes are typically defined by the direction normal. Crystallographers define them by their Miller indices (hkl).  Let a plane intersect not pass through the origin.  Then let the plane pass through the x, y and z axes at the points a, b, c.  If the plane passes doesn’t pass through an axis, assign the value of ∞.  Then the reciprocal of these numbers (when moved to a lowest common integer) are the Miller indices.  For example (001) is the xy plane

 

Slip

Slip is the usual method of plastic deformation in metals by blocks fof the crystal sliding past one another along definite crystallographic planes.  There exists a slip plane, and a slip direction.  The plane is the plane which gets moved and the slip line is the direction.  Generally slip occurs in the plane of greatest atomic density and the direction is the closest packed direction with the plane. This is because slip keeps a single crystal as a single crystal.

 

Dislocations

A dislocation is a type of defect in the crystal structure.  Specifically it is a line defect. It is what is responsible for slip.  Typically, it is an extra half plane of atoms in the crystal lattice.  This half plane can then move easily move perpendicularly through the crystal.

 

(In Future Include and describe some figures).

 

 

 

 

Sources:

Callister, William D. Materials Science and Engineering.

Slip Systems

Diplomacy Notes

I have started playing diplomacy online.  Here I am printing some of my commonly used opening messages so that I can reuse them in future games.

 

From a recent game as Austria:

Dear Turkey,

Conventional wisdom states that Austria and Turkey should each recruit allies and attack the other. However, I think that is a terrible idea. Why? Because, we both have bigger fish to fry in the beginning. Italy threatens your ability to dominate the Mediterranean and Russia will always be eyeing your territory in order to establish a good defensive position in the south with the inability to be flanked (the stalemate line runs right through Turkey. For Austria, it is nearly impossible to actually attack Turkey. No, it is impossible for Austria to attack Turkey’s homeland. Not only that but Germany, Russia and Italy are all eyeing Austria’s lands. I would therefore like to propose an alliance. An Austrian Turkish alliance. We will split up the Balkans 2-2 your choice on whether you want Rumania or Greece I will take the other and we can both agree to attack the enemy of your choosing (Russia or Italy) depending on whether you are interested in pursuing a naval strategy or northern strategy. This will allow Turkey early expansion opportunity and Austria some time to make her homeland safe.

Please consider my proposal,
Your friend, Austria

Dear Russia,

Perhaps nobody shares the security concern of the dual monarchy and the tsar. Not only do we both have 4 hostile neighbours, but we are both part of the dreaded central triangle (Germany, Russia, Austria). My experience says that a Russo-Austrian alliance is more beneficial, long term than a German-Austrian. We can collaborate more (on the Germans and the Turks), and more importantly an Austrian alliance seals off one of the more important defences in Russia.

Your Friend,
The Hapsburgs

Austria-Italian Relations

As you are aware, the center must hold. Austria and Italy are more or less forced to ally on the first turn. Italy needs help expanding (either into France) or into Turkey. Expanding into Turkey with Austria is the most popular option with good reasons. Your homeland is safe due to the alliance with Austria, and you get to attack Turkey through their most vulnerable location, Smyrna and Syria. I would suggest a Lepantao:
Naples to ION,
ROM to APU or NAP
VEN to PIE (note that the typical DMZ of PIE does far more for France than it does for Italy (and depending on your relationship with Germany and England, it gives you opportunity for growth.

Let me know your thoughts,

Austria

Dear Germany,

Austria and Germany both have the most complicated security relations on the board. For good reason they rarely attack each other in the beginning. The last game I played saw a Germany attack Austria and they were both eliminated by 1904. I would like to propose a mutual security pact. Right now you are probably more interested in the west, and I am more interested in the south, however I believe that it is in both of our interests to gang up on Russia if they come after either of us. If Russia is attacking the German or the Austrian, then we should work together to rid the world of such behaviour.

Dear England,

Your are perhaps Austria’s only natural ally in this game, by that I mean, you are close enough that we can help one another, but far enough away that neither of us covets the other’s territory. I have two issues I want to discuss. The first is Scandinavia. I believe that you should make it a priority to go after Scandinavia. The four supply centers can be held by only three units. I believe that it would be in your and my best interest if you were able to hold the nordic countries. More importantly, it would deny Russia and Germany those supply centers which they would only use to attack us.

The second discussion I want to have is on Italy. I believe next to a Turkish attack, the French opening is one of Italy’s bolder moves. Spain, Marseilles and Tunis make a good base of operations for Italy, so you might find a willing ally. On your end, that would leave you as the dominate naval power in the north and sitting in very good position. If I were you I would feel him out on this issue.

Your Friend, Austria

Diplomacy Notes

Vox vs. Miller Free Trade Debate

On Vox’s and Miller’s Free Trade Debate.

Listen to the debate here.

I thought it was rather interesting debate, however there are a few points I want to mention that I thought were not fully spelled out.

Protectionism isn’t a Lack of Trade

First, it is important to note that free trade is not necessarily the same thing as no trade. Which means many of the benefits, or at least some of them can be realized with a somewhat protectionist stance. I certainly believe that we should start with free trade and then move protectionist as needed.

Free Trade and the Movement of People

It is important to note that Dr. Miller is wrong about the movement of people. The example in this case is robotics. Vox made the point that if you want to specialize in robotics you need to move to South Korea or Japan. Dr. Miller rebuttal was that if a bunch of people wanted to not move to Korea or Japan, then they would have a competitive advantage in terms of wages. However this is irrelevant because there will be a technological advantage–mainly a knowledge advantage which will be different to catch up. My rule of thumb is that it takes 4 times less time to learn something when someone else is teaching you. So even if the engineers and manufacturers in, let’s say, Boston want to participate in robotics, they are still many years behind technologically. The difference in wages in high skill jobs cannot make up for technical knowledge. In order to make up the difference, either people from Japan and Korea neeed to immigrate to Boston to bring that knowledge. Or someone in Boston has to be willing to spend a lot of money reinventing the knowledge that exists in Korea and Japan. Note that however, if the investor were to spend the capital in Korea and Japan, it could be used inventing new technology. That is essentially the cost of getting Boston up to speed in robotics technology is economically wasted in terms of free trade. So truly free trade requires people who specialize to move to places where everyone else specializes.

It is worth noting, however, that there is a benefit as having many people in the same area encourages innovation and progress.  Examples include Vienna and Berlin as hotspots of physics and mathematics in the early 1920s and 1930s and Silicon Valley and Hollywood today.

Protectionism is a form of national defense

Perhaps the biggest argument, in my mind, is national defence. Without getting into a discussion on the theory of war, I contend that the ability to make guns, bombs, ammunition, ships, communication devices, and other instruments need for war are necessary for winning a war. It could be that you can purchase them, however the best way to assure that you can acquire them is to produce them yourselves. As such, having a huge manufacturing bases at home allows these tools to be redistributed for war more quickly and readily than building new facilities. That is the production of cell phones can be readily converted to military grade communications systems, however the production of social services or tourism cannot be readily converted into production. So every country has a desire to specialize in manufacturing for national defence reasons. This means countries are incentivized to subsidize these industries either through tariffs or direct capital injection. Free trade should therefore, quickly, develop into unfair trade.

Free Trade isn’t Necessarily Fair

One of the assumptions for free trade is  that everybody plays by the same rules. However this is, in general not the case.  There is a difference in IP laws, labor laws,  environmental and regulatory laws from location to location.  These differences will have an effect on each area to be competitive in different industries, and can have additional negative externalities.   Below I see two practical issues that occur today.

IP issues with free trade discourages innovation. There have been many reports of China stealing intellectual property. This discourages innovation because reverse engineering takes significantly less time than engineering.  Without proper intellectual property protection and enforcement, free trade could stand in the way innovation.

All the arguments for free trade assume fair trade, however this isn’t necessarily the case. For instance in the lumber industry, we cut trees down in America then ship them across the Ocean to Russia to be processed instead of converting them to lumber and paper here. The reason is primarily a difference in environmental and labor laws (primarily environmental). Specifically Russia and Japan allow their factories to use chemicals which the EPA has deemed harmful to the environment. As such we cut trees in the U.S. ship them half way across the world and then ship the paper back to the U.S. (As an aside this may no longer be the case.  I heard it from a friend who used to work in the pulp and paper industry 30 years ago).

A better example is that the U.S has bought one quarter of the world’s supply of mercury to drive the cost of mercury up.  This is because their is a reaction which will cheaply filter out gold from water, but it involves dumping lots of mercury into the water.  This process is legal in many parts of the world, so the U.S. has made it economically infeasible by buying up the supply of mercury.  While this is a clear case of economics working, it is also a very clear case of possible negative side effects of differing environmental laws.

Vox vs. Miller Free Trade Debate

Black Lives Matters and the Never Ending Fight against Racism

The fight against racism is never ending. Regardless of whether we call it sin, biology or tribalism, racism is natural. I am not saying that racism is morally right, what I am saying is that every generation will need to deal with it and those who seek to eradicate it face a never ending battle. This is because people have a natural affinity to prefer those who are like them. Similarity forms a natural bond between people and there is no similarity more obvious than skin color. Whenever people are shocked such as in The Necessary Recklessness of Campus Protests that no progress has been made since the 1960s, it comes from a misunderstanding of the human condition. Concerned student 1950 laments, “In 1968 the Black Student Movement issued 23 demands to the University. Almost 50 years have passed, but if you look at the demands you realize we are still dealing with exactly the same issues: little has changed.” This is because they are fighting against human nature. In spite of any changes that might be made now, in another 50 years, Mr. Turkson’s children or grandchildren will, unfortunately, be dealing with the same issues which he is dealing with now. I am certain both Mr. Turkson and I would prefer this to not be the case, but human nature hasn’t changed in the last 2000 years and is unlikely to change in the next 50.

Does this mean this fight isn’t worth fighting or that no “progress” can be made? Of course not, but we have to be smart about how we go about doing it. We also need to set realistic goals. I will not comment on what realistic goals are or should be because I don’t know.

Cialdini makes it clear that some methods are going to be effective while others will potentially backfire. His book isn’t explicitly about racism. But he uses forced desegregation in schools leading to an increase in racism as an example of how competition will cause a dislike. Conversely cooperation increases likeability of one another. Therefore, because many schools tend to be competitive environments, adding interracial cooperation would likely lead to a decrease in racism. It seems that a modest proposal which forces interracial cooperation for classes in the required general electives would be an effective measure to help combat the racism problem on campus. This of course leaves many open questions and certainly doesn’t solve everything. But this post isn’t about the particular solution, only the problem and how in general we should attempt to address it.

Black Lives Matters and the Never Ending Fight against Racism

Voxday’s Immigration is War

Is multiculturalism really the death of a nation?

A quick look at the Austro-Hungarian Empire.

One of Voxday‘s constant meme’s is immigration is war. This comes from an essay in There Will be War Volume X by Martin Van Creveld.  But more broadly it encompasses his belief that nationalism is an inconquerable force.  That is nationalism is a superior meta strategy than globalism.  I have yet to read the essay, but upon the coming of 20committee‘s history of the fall of the Austro-Hungarian Empire, I was interested in it’s history to see how the last historical multicultural empire/country faired.

From what I read, the Austro-Hungarian empire always had problems with sectarianism. They had clever leaders which helped them overcome the issues, but they were always internally weaker than their homogeneous neighbors.
At the fall of the Hapsburg empire,
In 100 years ago: Italy’s Terrible folly, John mentions the Slavic soldiers didn’t want to fight the Russians, which lead to problems on the west front.
In Przemysl, “Then there was the ethnic factor. Austria-Hungary’s military, like the empire itself, consisted of a dozen different nationalities, not all of whom viewed each other affectionately. Przemysl’s garrison consisted disproportionately of Hungarians many of whom had no love for Slavs of any kind Incidents of ethnic disaffection, even violence, proved difficult to ignore….” And “by early March… ugly incidents of inter-ethnic violence had become commonplace.”
Finally Serbian nationalists in Bosnia were the culprits in Franz Ferdinand’s Sarajevo assassination.

According to XXCommittee, while the empire had it’s troubles with multi-culturalism, it had three pillars which it could stand on:  1.) It had transnational, clever elites in the Hapsburg monarchy, 2.) It was solidly Christian with a tolerance for other religions and 3.) it had an army which was very devoted to the monarchy.

So my conclusion is that it can exist, but it will be slightly weaker than a homogeneous empire and it requires disciplined leaders

Yugoslavia
In comparison, Yugoslavia was functioning until economic and political problems made stirring up ethnic tensions the path to power for politicians .  XX committee has a wonderful article on Yugoslavia’s Warning to America.

Voxday’s Immigration is War

Jayne — Plausible Reasoning

In general, people do not use deductive reason, but instead must use plausible reasoning.  That is, almost always we deal with questions in which there is not enough information to permit deductive reasoning, yet a choice must be made.  A simple example is making plans based on the weather.  We don’t know what the weather will be, but we have to take part in activities (or not) regardless. Plausible reasoning is very subtle and this is why we all think everyone else is stupid.  To explain what plausible reasoning is, it is best to compare it to deductive reasoning.  Deductive reasoning follows two lines of logic: suppose that if A is true, the B is true. Then we can say two things if B is false, then A is false and if A is true then B is true.  Plausible reasoning, by contrast uses the weaker statements if B is true then A is more probable and if A is false, then B is less probable.  It is worth noting that B is only a logical consequence not necessarily a physical consequence.  For instance B could be clouds in the sky and A could be rain.  Even though the clouds are the physical cause of the rain, just because it is cloudy does not mean it is raining.  The degree of plausibility is then decided in some one manner.  In mathematics this is called our prior information in the real world it is referred to as common sense.  In spite the name, common sense is a complicated process.  Because the degree of plausibility changes based on our previous information, the reliability of the conclusion changes as we go through several stages.  Eventually, our conclusions could become nearly as certain as if we had used only deductive reasoning.

The study of plausible reasoning, and especially it’s mathematical formalism is of prime interest.  This is because the world is too complicated to analyse all at once. Therefore the method of science has been to separate into small pieces which can be separated.  The small pieces generate mathematical models or physical theories which we then use to try to explain more and more aspects of our physical reality.  Many different such models can be generated and plausible reasoning chooses between them.  Specifically, the mathematical formalism can help us choose between very similar models.  This formalism will also give us insight into how the human mind might work and finally it will teach us how to teach machines to think, atleast in some limited sense. So then, understanding probable reasoning will help us determine the laws which govern our world, help us determine how we think, and is the basis for legitimate artificial intelligence.

The study of plausblity reasoning has the same rules as probability theory.  This is not accident, they are one and the same.

Note that these are my notes on Jayne’s Probability Theory.

Jayne — Plausible Reasoning