Category Archives: Science

Technological or Societal Solutions?

I sometimes have an internal debate on what I think is the best solution to major world problems such as climate change, poverty, hunger, and so on. You hear these issues talked about heavily in political terms as to who’s responsible and why should any one government get involved. Well the answer to why governments should get involved is because they have the most power and ability to instigate change, much more so than any one person or group. But change requires money, effort, and most importantly of all, giving a damn. The last is awfully hard to find these days. Human are very selfish when it comes down to it. Our views are heavily tinted by our immediate surrounding, people, and concerns. So it’s hard to care as much about an abstract concept like climate change or world hunger when you live in a temperature climate, have air conditioning and heating, and plenty of food to eat.

Being an engineer and scientist, I tend to believe that if we only had the correct technology, that these worldwide problems could cease becoming problems altogether. If we can perfect carbon and methane remediation and clean power, there would be no man-made climate change. If we can create super cheap energy and hardy crops, we could push back poverty and hunger. We could save the world if only we had the technology.

But here’s the debate: which is the better way? I realized even if we did have the magic technology, implementing them would eventually run into politics, especially if they threaten some industry’s profit margin. Nothing makes politicians take notice faster than a lobbyist coming to them with a donation and a story about a new threat to their interests. But, in all of history, old ideas, traditionas, and technologies eventually get replaced by newer, better, and more efficient ideas and technologies. For example, The horse and carriage were replaced by the model T and cars once we discovered the internal combustion engine. Now we can go farther for less money. Clothes making also made the transition from old to new long ago. In pre-industrial times, individual tailors and seamstresses made clothes by hand, and most people own only a handful of outfits. Industrialization, the assemblyline, machines, and the computer chip largely killed the clothes-making profession, except for specialists. But in return we can buy shirts, dresses, and pants for very low prices. I imagine during those transition periods, there was a lot of argument and distain for the new technology by those involved and invested in the old ways.

Energy is currently in the transition period I believe. Coal, natural gas, and oil have been the foundation of civilization since they first found you could burn coal and oil. However, we know there is a limited amount of the stuff around. Yes, even the oil companies, which is why they all put some money into looking for new oil sources and new energy technologies. However, they are very dependent on the existing market in fossil fuels to keep their business running and their stockholders happy. At the same time, solar power, wind power, and electric cars are slowly becoming more mainstream and forming a small but growing portion of our global civilization. Various countries have agreed to the Paris Climate Accords which among other things states that we should all try to move towards a larger percent of renewable power and away from fossil fuels. I feel in the next 50-100 years our energy grid will be dominated by renewable energy and electric or fuel cell cars. Even oil companies project that current resources won’t last more than 100-200 years. At that point, they’ll be completely out of business since there will be no oil anywhere, or anywhere reachable. That would seem like a good reason to start in the direction of renewable energy right now and fast. However, remember humans are not only selfish, but short-lived. 100 years sounds like a short time to me, but I know I won’t be around to see it, and neither will all the investors and executives companies. They may have a greater interest in the here and now since what happens 100 years from now doesn’t affect them. That is one of the greatest failings of the human mind and civilization I think. The lack of foresight and empathy with the future may one day damage the planet irrevocably. While I may not be alive in 100 years, my children will be, and then my grandchildren will inherit the world we’re building now, for good or ill. In Eastern culture in general, there is the strong belief that one’s main goal in life is to make life better for your children. My parents sacrificed and worked hard so I could have more opportunities and a better life. My dad always says children should exceed their parents since each generation strives for the next. I also personally believe that the meaning of life is to leave the world a better place than you found it. That’s my general belief for most situations, do more good than harm and leave it better for the future.

So in the end, there is no one magical technological solution to the world’s problems. All solutions require the cooperation of people and thus governments and companies. And as long as people are involved, there will be politics and self interests. As engineers and scientists, we are trained to see the future by learning from the past, so we should strive to not only develop the world saving technologies, but encourage everyone else to keep the future in mind.

The Trap of the “Science Hammer”

At the most recent AIAA SciTech conference, I met a gentlemen from the Air Force Academy who teaches there and reviews research proposals for the Air Force. He gave a talk to the plasma aerodynamics group on plasma actuators and why those proposals have not been funded much recently. He also raised a point, which is the focus of this post, that plasma is not always the solution to the problem and we as a community should stop using it as a proverbial hammer to hit every problem nail.

First, a little background and explanation. As scientists and researchers, we are all trained in some specialty, whether it’s plasma physics, rocket propulsion, high speed aerodynamics, piston engines, mammalian habitats, insect DNA, etc. Of course some specialties are broader than others. So we tend to do research in our specific areas, or areas that are similar enough that we can bring a part of our experience to bear. The further the research is to our core specialty, the hard it is and less likely others will fund you or trust your results. Yes, there is some bias in science. So this specialty is what I called the “science hammer”. Like a craftsman, we have one or two types of hammers (knowledge) in our tool belt. So when we encounter a science problem, our first thought is to hit it with our hammers. Another way to say that is when you only have a hammer as your tool, then every problem is a nail to be hit.

I have been thinking on this “hammer” and the suggestion the gentlemen at SciTech gave. My hammer is plasma. I sometimes jokingly say plasma can solve all your problems, or I’m always looking for things to point a plasma at. Now plasma is a pretty energy inefficient process by its very nature. Unlike a fire, you have to continuously supply the plasma with energy and fuel to keep it going. The fire will keep burning as long as there’s fuel. Once started, the fire provides its own energy. So in many cases, especially aerospace applications where energy is limited, plasma may not be the best solution. The example the gentleman gave was plasma actuators for flow control on airplane wings. Plasma actuators can improve the flow and reduce drag on wings. But the practical question becomes is it worth it? It takes extra energy to generate and sustain the plasma, and it seems at least for plasma actuators the benefits are not worth the cost.

Now there has been considerable interesting science to come out of the last 15 years of research into plasma actuators. So all is not lost. But the funding agencies have learned a lesson if you will. They’re more cautious about plasma-based solutions since they recognize the issues with plasmas. So in my position as a principle investigator looking for funding, I am not trying to by smarter about what I apply plasma to. It has to be credible, doable, and provide a net benefit. I have also begun to look at way to use plasma not as the solution, but as a diagnostic or tool to study a phenomenon. I’ve been talking with another faculty about using plasma actuators to study flows. Hopefully the advantages of plasma can be brought to bear and without worry about its overall efficiency since it doesn’t have to fly.

Bigger, Better, Faster, and…Cheaper?

My research is in plasma physics and propulsion with a focus on practical applications. To develop new technologies you have to push against the boundary of what is known, and that take times and usually happens in small incremental steps. In other words the new technology is only a little better than the current technology. For some things like computers and smartphones, a little better seems to sell, thus a new iphone every 6 months, even though they may not be a substantial improvement over the previous version. However in spacecrafts and propulsion, a little better isn’t good enough. The motto of propulsion has always been bigger, better, and faster engines. However in recent times an additional property has been added, cheaper. Now that seems to be at odds with the previous three. How do you get a bigger engine for less money?

Better and cheaper is usually an oxymoron for technology. To make something better, usually in performance, requires improvements in materials, science, coding, and so forth. All that of course takes time which costs money. Then if you have to use higher performance materials or components, those cost more money. Lets say you want a higher performance jet engine for airplanes. Maybe you run the engine faster or hotter to get more thrust. That requires higher strength materials to withstand the higher temperatures and stresses. If the engine runs faster, you may need more robust gears or shafts to transfer the force. Thus the engine is more expensive.

The exception to the rule where you can get cheaper and better, eventually, is when a paradigm shifting technology or process comes along. Computers are a prime example, or rather the production of computer chips. Computer used to run on vacuum tubes and punch cards and took and entire room. Then came the discovery of semi-conductor materials, transistors, and the methods to produce them. Now computers can fit on a desk. Now the technology to produce computer chips continues to advance to make smaller and smaller transistors. This allows you to put more and more transistors on a square inch of silicon. This not only allows you to increase the computer speed, but also means you can make lower performance chips using less material thus less money. Thus today the $100 tablet is much more powerful than the room sized computer of the 60’s.

So to get bigger, better, and cheaper you need a paradigm shifting new technology. In space and propulsion, those are harder to come by. We are currently push up against the theoretical limits of jet and rocket engines. There’s just not much more room to improve according to the laws of physics. So there’s not alot of impetus to develop new engines. New jet engines are still being developed not necessary for better performance, but to reduce emission and operating costs. Currently there is some rocket engine development occuring in the US. Aerojet and Orbital ATK are both spending their own money to develop a new liquid rocket engine, though it’s not going to be drastically better than the existing engines. The RS-25, better known as the Space Shuttle Main Engine, is the highest performaning rocket engine ever developed by humans. It is also horrendously complicated and expensive. The new engines are unlikely to try and meet or beat the SSME’s performance. So why is money being spent to develop a new engine that’s not going to better than the best we have? The answer is politics. The new engines are being developed to replace the Russian RD-180 which we currently buy from Russian to power the Delta and Atlas rockets. Given the recent tensions with Russia, Congress has decided giving money for rocket engines is bad. So this is a case of not better, not cheaper, but necessary due to non-technology issues.

In my mind, there are two contenters for paradigm shifting technology in propulsion: nuclear, and addition manufacturing (3D printing). Fusion propulsion has the potential to make interplanetary travel much faster and eventually cheaper. But the technology is still in its early stages and will be very expensive to develop. So fusion propulsion can satisfy the better desire. The cheaper part could be fullfillled by 3D printing. Additive manufacturing can greatly reduce the time and cost to produce components, which will make things cheaper. It also has the potential to make very complex components which may improve performance if designed correctly. Companies have already 3D printed small rocket engines or parts of rocket engines and shown the parts can survive the high temperatures and pressures. Initially 3D printed parts won’t have better performance than their conventional counterparts, and in some cases may have worse performance. But as the technology is further developed, 3D printed engines could also reach the better criteria.

What, Why, How, and So What of Paper Writing

One of the most difficult and perplexing part of research and by extension graduate school is writing and publishing your work. It’s a key part of the research process and important for building your own career. But how to write a technical paper well is often unclear to new students. It took me a few papers before I got there hang of it, and sometimes it’s still hard to figure out where to start. The easier part for a student to write is usually the results since they have the data. But just data is not enough. You can tell you’re getting better when there are fewer revisions between you and your advisor and they make fewer red marks.

Your research paper or presentation is a bit like a sales pitch and debate rolled into one. You want to give a clear, concise, and logical argument for the validity and impact of your work. On one hand you want to convince the audience that your work and results are significant and add to the greater body of knowledge like a sale’s pitch. On the other hand you need to defend your techniques, results, and theories like a debate. For my students, I tell them the paper and/or presentation should answer the “What, Why, How, and So What” of the research. These are usually what the reader or audience is looking for, consciously or not.

What: What are you doing/what did you do? This is the simplest question to address. This could be a few sentences in the abstract or intro that talks about what the work you’re taking about is and the goal of the project.

For example: “This work conducted experimental measurements of the size distribution of the Whos in Whoville using electron microscopy. The goal is to determine if exposure to elephants alters their growth patterns.” (I recently watch the movie Horton Hears a Who.)

Why: Why are you doing this work? The immediate answer maybe “because my advisor/boss told me to.” That is not the answer you’re looking for. The why question address the big picture. Why is this work important? What kind of impact can it have if successful? This is your selling point if you will. Maybe your work can lead to a cure for cancer, or more efficient car engines, or a better way to do space travel, or a better technique to teach children. The why question gives the reader and audience the reason to care about your work.

To continue the example: “This work is important because Whos are an endangered species that is easily affected by outside forces. The recent exposure to Horton the elephant is a major change to their environment, so we need to know if that event changed their anatomy.”

How: How did you do your work? This question covers the methods and techniques you use. You may have done experiments that used a particular probe or calculation, or developed an equation using a set of theories. So the how question address the validity of your process. In answering the “how”, you need to put on the debate hat and provide logical and technical backing and justification for the steps you too.

Example: “The size measurements were done using electron microscopy. Volunteers from Whoville were recruited to participate in exchange for ipods. A survey of each Who’s daily routine and their activities during the Horton incident were done.”

So What: So what’s the significance of your results? The last question is the take away the audience should have from your work. Until now you have presented on what you did, why it’s important, and how you did the work, and presumably the actual results. Now you need to bring it back to the larger picture and answer the question of “so what’s the point?”

Example: “The results have shown that the Horton incident caused the Whos to growth 5 microns taller on average, based on the sample measured. This indicates that the Whos are greatly affected by external factors. However it is not yet clear if the elephant was the primary factor in the height increase. Another external factor may be the high altitude of Whoville’s current location that increases their exposure to UV radiation compared to their previous sea level location. Further research is need to clarify the triggers.”

Amusing example aside, this is my technique in a nutshell for writing papers, and it generally lays out the paper in a logical order. What and Why would be in the abstract or into. How would be in the experimental setup or theoretical background. Then there’s the results section which is usually the first thing students think about. Finally the So What covers the discussion and conclusion. As you gain experience in paper writing, you’ll develop your own methods and you’ll recognize how others write. The goal is always to present a clear, concise, and logical argument for your work.

The versatility of plasmas

I recently gave a talk to the student branch of AIAA on my research and plasma applications. I always thought plasmas were cool and useful. Putting together the presentation only reinforced by belief. There are two broad types of plasmas, high-temperature thermal plasmas, and low-temperature non-thermal plasmas. Examples of the former include lighting, arc welding, fusion, the sun. So not very useful for most things. The latter type, non-thermal plasmas however has lot of uses. But first lets talk about what makes up a plasma and why they can be useful.

Plasma is basically a gas with a large fraction of charged particles, usually positive ions and negative electrons. For example an argon plasma may have 80% of the total number of particles as ions, and a corresponding number of electrons. An ion is simply a neutral atom that has been stripped of one or more electrons. So for every ion, a free electron is also created. For the most part the ion has similar properties as the original atom, however because it has a positive charge, the ion, and electrons, will respond to electric and magnetic fields. Thus we can control the behavior of a plasma with externally applied fields, for example to accelerate the charged particles.

This can be used to give the charged particles more energy, so that when they collide with other particles, they can cause reactions. That is one of the primary use of plasmas: to promote or cause chemical reactions. This is the basis of plasma processing and etching that is used to create semiconductors which go into all electronics. It is also used to create high temperature coatings for engines, and water shedding coatings for clothing. The collision of energetic ions can also release light. This is the basis for much of our lighting technology today such as florescence lights in buildings and HID lamps in stadium lights and car headlights.

On the less common end, plasma is also used for space satellite propulsion, to create fusion here on Earth, control air flow on airplane wings, or used to remove plaque on teeth. In fact plasma is the most common form of matter in the universe. It makes up about 99% of the visible matter in the universe, most of it in the form of ions and electrons in the space between planets, stars, and galaxies. Our Sun, and stars in general, exist through inertial fusion of hydrogen and helium ions, i.e. plasmas. So plasmas are ever present, allow life to exist on Earth, and make civilization better.

“Transformative” Research

A part of a faculty and any scinetific researcher’s job is to serve on review panels for other researchers. Many government agencies such as the NSF, NIH, DoD, and DOE all use external experts in areas of interest to help determine if a proposed research idea is worth funding. I’m specifically refering to open solicitations for research proposals wherein anyone can submit a written proposal to do something and have the chance to get the government to fund the work. Usually a funding agency request proposals for a broad topic, such as combustion, advaced materials, novel manufacturing technologies, space technologies. Each of these topics covers a wide range of possible ideas and fields, so they get a lot of proposals, anwhere from dozens to hundreds. The question is then how do you separate the wheat from the chaff, and do it fairly so most people don’t get upset (someone always gets upset). The most common solution has been the peer review.

In a peer review, other experts or researchers in your field of work will read your proposal and score it. The criteria varies from agency to agency, but typically the proposals need to be coherent, scientificaly sound, can be done in a reasonable time frame, has a good chance of succeeding, and the point of this article: be transformative.

What exactly is transformative research? One could argue it is work that changes the way we view the world, or gives humanity an ability to do something never done before. Some examples may include Einstein’s theory of relativity, the Bohr model of the atom, Fermi’s discovery of nuclear fission, discovery of the Higgs Boson, 3D printing, supersonic flight, data encoding, the first electric car, using microwaves to heat food, TV transmissions, and so on. Some of these examples are large milestones in the history of science, others are things we take for granted in our daily lives, but at some point in time they were new and drastically changed the way we live today.

So transformative research could be a lot of things, and will be in the eye of the beholder in a peer review process. I had the opportunity to do such a peer reivew, and I wrestled with this question of transformative myself. Some of the proposals were addressing a very specific and niche questions, which would be very useful to one field, but did not obviously help other fields. Others looked at big picture questions, but would be unlikely to get a detailed answer. Some proposals sought to answer very fundamental questions of physics, others just wanted to poke something and see what happens. One proposal comes to mind that sought to do an interesting experiment in an uncommon field, and take a lot of data, but would be able to address the fundamental physics because of the way it was set up. The results would not really tell us about the physics of what is going on, merely provide empirical trends (outline the problem as it were). I was at first against the proposal because I thought transformative meant there had to be great science and physics. But after talking to other reviewers, I realized that another transformative aspect of the proposal was just the fact it would do something no one has tried before. So even if the results wouldn’t be Earth shattering, it will be results and open the door for others to pursue the detailed science. So I’ve obtained a new appreciation for what is “good” research and worth doing. Sometimes you need to get the outline of the problem first, before you can even try and dig deeper. Thomas Edison failed hundreds of times to make the light bulb, no amount of detailed research into the physics of thermionic emissions would have helped him at that point in time. Instead he just had to keep trying to outline the problem of what material would make the light bulb filament.

The lesson I learned personally from the experience is there is no one definition for what is important, transformative, novel, etc. Some very simple things could be ground breaking in their respective areas. Some research may also not seem immediately transformative, but it may provide new answers and results that can impact a different field and improve our understanding of the universe and improve our lives.

“Everything ends in plasma!”

The title of this post is a quote from my wife. One morning, I’m sitting on the couch and she comes into the living room and says I “have to read the xkcd book because everything ends in plasma.” For a bit of background, my Ph.D. thesis work was in plasma propulsion a.k.a. electric propulsion. At UAH my research is in more general plasma physics and applications that include propulsion, but also include combustion, materials, and basic science. So anytime plasma is mentioned I perk up. Plasma is known as the 4th state of matter. It is a gas with significant fraction of the particles as ions and electrons. This way it can be affected by an electromagnetic field.

XKCD is a webcomic written and illustrated by Randall Munroe. It has a decidedly science and math bent to its jokes. Over years, xkcd readers have post a bunch of “what if…” questions to him on the forums which he answers in a scientific and humorous manner. Recently he collected the best of them in a book: “What If?: Serious Scientific Answers to Absurd Hypothetical Questions”. I bought this book for my wife for her birthday, thus her reading it.

Now that we’re all caught up, back to the story.

Apparently a number of the what if scenarios in the book pass through or end with the object or scenario in question becoming a plasma. For example, a question is asked in the book about what would happen if you shinned laser pointers at the moon. The answer is not a whole lot. The energy and illumination of laser pointers are tiny compared to the light from the moon and the size of the moon. But the book raises the stakes and keeps ramping up the size of the laser. As the lasers get powerful, and we assume a few million people are pointing at the moon simultaneously, things do start to happen. The final stage is millions of the lasers used at the National Ignition Facility where they do fusion research by shooting lots of high power lasers at a marble. So the what if scenario has the moon being hit with millions of these lasers, and this heats up the moon a lot.

If you heat up a solid material, say with a laser or a super hair dryer, it will first get hot as you energize the molecules that make up the material. Ice is a good example. As the ice gets warm, the bonds holding the water molecules in a solid form break and it becomes a fluid. As the temperature keeps going up, the bonds holding the water molecules together as a liquid break and the water becomes a gas, water vapor. Now if you keep heating it up, you’d likely break the bonds holding water molecule together first. So the bonds between the hydrogen and oxygen would break and you would no longer have water, but a cloud of hydrogen and oxygen. If you keep heating it up, assuming it doesn’t blow up as hydrogen and oxygen are highly combustable, then you would next see the outer electrons in the H and O atoms popping off and escaping for the atom. If a large enough number of the atoms loose an electron, you then have a plasma.

So if you hit the moon with millions of super lasers, first it would go from moon rock to molten moon liquid, then to moon gas, then to basic elemental atoms, and finally those atoms would loose electrons and you’d get a plasma. This would apply to anything if you apply enough heat and energy. So truly, everything does end in plasma, if you try.