Jane M Fraser

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What’s new?

Interesting Engineering reported that the CEO of Turkish cryptocurrency exchange Thodex fled to Thailand with $2 billion of crypto assets, leaving 400,000 users of the exchange in the lurch.

What does it mean?

Blockchain is a computer technology that prevents changes from being made to a series of records; the most important features of blockchain are distributed storage and a type of internal consistency (one block of data is related numerically to the previous block, hence “block chain”). If someone wanted to change a record in a blockchain, they would have to change the record in many, many locations, and would have to change many, many records in order to maintain the internal consistency of the records. Blockchain thus can prevent certain types of fraud, that is, fraud in which records are altered. Blockchain creates unalterable accounting records. Blockchain is currently used for cryptocurrencies such as Bitcoin, that is, currencies created and maintained as computer records.

Most implementations of blockchain rely on proof of work to establish and maintain the records. When a new record is added, blockchain sites perform long and complicated calculations (following the internal consistency rules) to add the record; the first site to present proof of the completion of that work, called mining, is rewarded with additional cryptocurrency.

Blockchain protects against only certain types of fraud, that is, fraud involving the changing of accounting records. Blockchain will not prevent many other types of fraud. In fact, the whole area of cryptocurrency has a great deal of fraud; an Internet search on the words “blockchain fraud” or “blockchain scam” will turn up many examples.

Consider, as an example, an area of fraud I was concerned with for my 40 years as a professor of engineering: cheating by students. Blockchain could protect against recorded grades being changed fraudulently, a type of fraud that does occur. I am aware of several such cases that were detected and there are probably others that went undetected. But cheating by students takes many other forms, none of which would be prevented or detected by blockchain, for example, someone copying another’s work on homework or during a test.

Blockchain is also touted as useful for verifying someone’s identity and for establishing trust in business dealings with unknown partners, but I suspect that the actual usefulness is more limited than the hype and that other computer technologies can accomplish such goals. The mathematics of computational complexity, which I discussed two weeks ago in this blog post, underlie all these technologies for computer security.

What does it mean for you?

Blockchain, as with many new technologies is the subject of much hype, some of which is misleading and even incorrect. For example, this article at Forbes says:  “Were the expensive free-range eggs we purchased really created at a free-range farm?  Was the gold ring I bought online really made with 24K gold? Companies can combat fraud with blockchain by verifying the legitimacy of every part of the supply chain process, helping both the buyer and manufacturer. You’ll never have to question that organic produce and those free-range eggs.”

I disagree. Nothing in blockchain can prevent someone from, at any point in the supply chain, substituting eggs from caged chickens for eggs from free-range chickens, just as nothing in blockchain can prevent a student from looking over the shoulder of another student during a test.

Blockchain does have important uses. The immutable nature of blockchain records is an important feature in maintaining security. But most hacking episodes involve stealing private records, not altering such records.

I am not addressing here the huge amount of electricity required for the proof of work aspect of blockchain (see, for example, “Bitcoin consumes ‘more electricity than Argentina’”) because, I am told by my local blockchain expert, other methods of blockchain do not rely on proof of work. I am also not addressing the independence of blockchain from regulations or governments (as part of crypto anarchism, for example), which others cite as an attractive feature; one upshot is that your recourse in the case of fraud and scam are limited. And, whatever you do, don’t lose your password; if you do, you lose your assets.

Where can you learn more?

This 2018 article “Blockchain is not a silver bullet for fraud prevention” is still very useful. Here is another article cautioning about the hype. This December 2020 article in Finance Magnates blames the lack of a killer application outside of cryptocurrencies for the failure of blockchain to achieve its promises. This December 2019 article uses a Gartner diagram of the phases of hype to speculate that blockchain will be useful five to ten years from now. This piece in TechBeacon lays out in detail some of the pitfalls of blockchain.

Some argue that blockchain eliminates the need to rely on trust  in business transactions, but this article by noted cryptographer Bruce Schneir points out that trust is always needed. He asks “Would you rather trust a human legal system or the details of some computer code you don’t have the expertise to audit?” He includes this image tweeted by Internet pioneer Vinton Cerf:

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What’s new?

An article from GlobalSpec Engineering360 combines some of my favorite topics: new materials, the element carbon, and additive manufacturing. This article was just one of many I read this week on additive manufacturing.

What does it mean?

Plastics and carbon nanotubes were combined in a new internal configuration to create a material with improved strength, toughness and stiffness, and lighter weight. Such a material could have significant application in replacing metals in vehicles.

One useful piece of technology in the Star Trek science fiction series was the replicator, used to create food, including Captain Picard’s Earl Grey tea. This article taught me that it was also used to create spare parts and items for consumption on the Holodeck simulation and that “By virtually eliminating material scarcity, replicator technology plays an important role in the moneyless human economy within the Star Trek universe.” This article expands even more about how it was used. The physical explanation (“matter-energy conversion”) is suitable for science fiction but not for science.

Regular readers of this blog know that I am interested in additive manufacturing. My interests include the technical aspects of the new materials and include the technical aspects of how the new materials are created, but also include the potential for changing supply chains, manufacturing, and our economy. While the abundance enabled by the Star Trek replicator is still science fiction, the future may involve using a limited number of feedstocks to create consumer products on demand, close to the final consumer. Your local big box store will be a manufacturing facility, turning carbon (and other materials) into products.

What does it mean for you?

Manufacturers should be excited about the potential for additive manufacturing to change their processes as well as the processes of their suppliers. The technology is changing the economics of additive manufacturing enough that it can now be used for small batches and larger batches as well, enabling customization in mass manufacturing.

But manufacturers should also be cautious: parts made with additive manufacturing are different. The article I cited above points out that the new material creates objects with different strength, toughness, stiffness, and weight. Careful thought must be given to the implications of these changes in use: for example, decreased weight may be a benefit for shipping, but may create issues in the ability of an object to remain stationary in wind. Is lighter weight lawn furniture always desirable? In addition, additive manufactured parts are usually created in layers and thus can tend to delaminate, with implications for durability.

Also, replacing conventionally made parts with those made by additive manufacturing can have other implications. Because additive manufacturing can create parts with shapes that were difficult to make by other manufacturing processes, an assembly of parts may possibly be made as one part, as explained here, with implications for the manufacturing work flow and for the workforce.

I often note that fasteners are a sometimes overlooked part of engineering design. This article explores how traditional fasteners (screws, for example) work with parts made with additive manufacturing and this article explains that the fastener may need to be selected to add strength to thinner parts made by additive manufacturing.

I hope that you share my excitement about additive manufacturing, but I also hope that you share my caution.

Where can you learn more?

While I subscribe to some email lists that tend toward coverage of a wide range of additive manufacturing, generally still in the research stage, applications of additive manufacturing that are actually being put into practice are probably more likely to be found in conferences and publications for that industry, such as the Food Automation and Manufacturing Conference and Expo. Food Technology Magazine had this 2020 article on how 3-D printing and other technologies may change the production of food.

Some sites that cover additive manufacturing, for example Additive Manufacturing Media, do have good articles on specific industries, such as this recent one on 3-D printing furniture.

I tend to use the phrase “additive manufacturing” as being more descriptive of the technology, but an Internet search should also try the term “3-D printing” since it is widely used.

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An illustration of a mathematical optimization problem with two decision variables (shown on the horizontal and vertical axes), three constraints (shown in black, teal, and purple), and a linear objective function (shown in red) that is to be maximized. The optimal solution is 130 for the variable on the horizontal axis and 20 for the variable on the vertical axis; that solution yields a value of 49,000 for the objective function.

What’s new?

As reported by Nature and phys.org, the 2021 Abel prize was awarded to mathematicians László Lovász and Avi Wigderson for their work on computational complexity.

What does it mean?

If, like me, you enjoy putting together jigsaw puzzles, you know that every puzzle is labeled with an important number: the number of pieces. That number is a fairly good predictor of how much time it will take you to put together the puzzle. Once the puzzle is done, you know you have solved it correctly simply by seeing that the resulting picture is complete. You have found the unique, best solution.

Much of what computers do takes the form of solving mathematical puzzles: finding the best route for a delivery van, assigning flight crew members to flights in the best way, assigning jobs to machines in a production facility, deciding on the best way to cut a tree trunk into lumber, and so forth. For many mathematical puzzles, like the jigsaw puzzle, the size of the puzzle is a fairly good predictor of how long the puzzle will take to solve, and for some – but not all such mathematical puzzles – when you have found the best answer, you can easily confirm that the answer is the best.

The field that deals with solving mathematical puzzles like these is called optimization (notice the use of the word “best” in each of the stated puzzles above) and the field that studies the difficulty of such puzzles (how long will the puzzle take to solve) is called computational complexity.

In optimization, the puzzles we solve are expressed in mathematical form. We want to select values of decision variables to maximize or minimize an objective function (expressed as a function of the decision variables) while meeting all of the constraints of the problem (expressed as inequalities or equations, again as functions of the decision variables). In my June 27, 2020, blog on operations research I wrote about linear programming as an example, where the objective function and constraints are all linear functions of the decision variables, but other puzzles we want to solve may not be linear. Also, in some puzzles, the values of the decision variables are restricted to be integers (that is, numbers with no decimal part): you can’t assign 0.8 of a crew member to a flight, for example.

Computers solve these problems by using algorithms: an algorithm tells the computer program exactly what to do and the computer chunks away and eventually tells you the best solution to the problem. The issue is how long it will take the computer to find the best solution, and in some cases the answer is disappointing: more time than the total time so far in the universe. Imagine a jigsaw so big that it would take almost forever to complete. In such cases, we may need to use a heuristic, which is a method that can get us an answer to such problems that may not be the best answer, but that we know it is a good answer.

In some puzzles, when you have found the best answer, you can easily confirm that the answer is the best. If, by luck, you pick up a jigsaw puzzle piece and it clicks into place, you know you are correct. With some mathematical puzzles, introducing randomness into the heuristic can speed up the process of finding a good, even best answer.

As the Nature article on the Abel prize says: “But since the advent of computers in the twentieth century, the emphasis in research has changed from ‘can an algorithm solve this problem?’ to ‘can an algorithm, at least in principle, solve this problem on an actual computer and in a reasonable time?’”

The winners of the Abel prize contributed to the solution of mathematical puzzles and to the field of computational complexity. Lovász has contributed to the solution of mathematical puzzles that can be expressed as movement on a network, seeking the best solution. Wigderson’s contributions relate to the use of randomness in finding solutions and relate to so-called zero-knowledge proofs, a way of proving that a puzzle has been solved without actually revealing the solution.

What does it mean for you?

Computers do more and more for us every day (just take a look at your cell phone), often relying on algorithms and heuristics to solve mathematical puzzles. We want them to solve bigger and bigger problems, so the answer is always, get a faster or bigger computer, but computational complexity helps the designers of algorithms know when a faster computer is likely to be successful and when the problems are simply too big to tackle. The results of computational complexity are important in guiding this work.

Paradoxically, sometimes we want to design problems that will take an enormous amount of time to solve; that idea forms the basis for most computer security. Guessing your 16-character password is beyond the reach of most computers. Complexity theory underlies cybersecurity and encryption, the methods that are meant to keep your information safe from attack. It also forms the computational basis of crypto currencies such as Bitcoin.

Where can you learn more?

The Britannica article on optimization is a nice introduction to the field, including some history. This article from Forbes discusses the types of business problems that can be solved by mathematical optimization. The professional organization INFORMS is one of several for professionals in optimization and computational complexity; they have an excellent history of mathematical optimization here.

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Source: Wikimedia.This file is licensed under the Creative Commons Attribution-Share Alike 4.0 International license.

What’s new?

One of my former graduate students is now fairly high up at Facebook Reality Labs and she sent me an Oculus Quest 2 (also a charger and an Elite Strap). I have now subscribed to Supernatural and I am exercising more than I have in decades.

What does it mean?

The Oculus Quest 2 is a fairly bulky, but surprisingly light, set of goggles and two controllers, one held in each hand. Activation requires a Facebook account and use requires a wifi signal. Supernatural requires the associated phone app. Setup was trouble free for me. An Oculus Quest 2 costs $300 for 64GB storage and $400 for 256GB, including shipping in the US. A Supernatural subscription costs $179 for a year.

In Supernatural, I can select from exercise videos of High, Medium, and Low intensity (and from meditation videos) of various duration (from as short as 8 minutes to as long as 45 minutes). Inside my goggles, I am placed in a beautiful outdoor location (including one on Mars). I appear to be standing on a computer-generated mat, usually several feet off the ground. I can move to look around and up and down in the scene. A new video is issued each day and hundreds of old ones are available. I have created a list of my favorites.

The exercise routine starts with a warmup from a coach who is located on a computer-generated mat about 10 feet in front me and then consists of several songs (usually rock, pop, hip-hop, etc.). During the routines, my hand controllers appear to be light sabers (called bats in Supernatural) with which I strike at oncoming spheres, black for targets to be struck by the black bat in my left hand and white for the white bat in my right hand. My accuracy and power scores are recorded and reported to me between songs and at the end of the session, which ends with a cool down from the coach. During the entire session, the coach’s voice provides encouraging (and sometimes amusing) comments.  

The quality of the vision is remarkable. I have set my initial room in Oculus to a place in a Japanese inn, with a view of an outside street scene and nearby pond of fish. When I move around, the view changes with 3D fidelity. The sound is also very good. When I am standing in the exercise mat in Supernatural, several feet off the ground, I have to keep reminding myself I am standing solidly on my house floor. I have my goggles adjusted so I get a slight view of my real floor if I glance down past my nose, keeping me oriented.

For use while standing, as I do in Supernatural, the Oculus interface requires me to set a safety perimeter in which there are no objects, and it generates a visual signal if I move any part of my body outside that perimeter. Because its use is linked to a Facebook account, privacy issues arise. A friend created a second Facebook account just to use with Oculus.

I have gone through three waves of emotion concerning Supernatural. First, I immediately loved it: this is fun! The movements, the dance, and the exercise all felt great. Then, as I got used to it, I started to pay attention to the two scores: accuracy in hitting targets and power, scored relative to expectations based on my most recent performance. I started to try to get 100% accuracy and high power scores. I hurt my shoulders and the fun decreased. Now I am back to focusing on the fun and ignoring the scores. The strikes and movements are, I now realize, really well choreographed and I focus on feeling that movement. I am back to: this is fun!

In my seven decades of life, I have sometimes exercised a lot, sometimes less, and recently, (now dogless, so lacking any canine friend I always called my personal trainer), I have had trouble making a habit of exercise. I am, with Supernatural, exercising 30 to 40 minutes every day, with noticeable results. I have to pace myself so that I don’t overdo my workouts and hurt myself. Supernatural is fun! The Supernatural Facebook page has ample evidence that it has changed many lives for the better.

What does it mean for you?

Virtual Reality (VR) has been touted as useful for training and now I get it. The view from inside the goggles is not perfect, but it is remarkably good; most noticeably it tracks my movement adjusting the scene flawlessly. It is so good that when I tried a roller coaster ride app, I noped out of that very quickly. Also, the hand controllers allow for various interactions with the virtual reality, including grasping and using objects.  

The Virtual Reality Society provides a list of applications in various areas. In their business category, they list virtual tours of a business environment, training, and a 360 view of a product. VR gaming is very popular, including opportunities to interact with others.  “The best VR apps of 2021” at digitaltrends includes apps allowing the user to create spray graffiti, to watch 360 videos, and to explore 12 underwater environments, This example at Lenovo reports on the use of VR to restore memories for dementia patients

My three stages of emotion in Supernatural reinforce my belief that scoring systems designed supposedly to motive people actually undermine intrinsic motivation and thus long term behavioral change. As a professor, I told students that grades undermine learning.  Alfie Kohn has written great books on motivation, especially in the field of education.  I recently learned of a quote from Barry Schwartz (a professor of psychology at Swarthmore College, my alma mater): “when you rely on incentives, you undermine values.”

Where can you learn more?

The tag line on the TV improvisational comedy show “Whose Line is it Anyway” is “where everything is made up and the points don’t matter.” Or on video here. 

I read the Barry Schwartz quote in a recent report from the NAACP: “Fossil Fueled Foolery. An Illustrated Primer on the Fossil Fuel Industry’s Deceptive Tactics.” The second edition, issued on 1 April this year, is anything but an April Fool’s joke and I highly recommend it.

Alfie Kohn’s website describes his books; my favorites are Punished by Rewards and No Contest. In his latest blog post (8 March 2021) he quotes one of my heroes, John Dewey, on the bad effects of sugar-coating. Kohn remarks: “These days an awful lot of such sugarcoating is done digitally — for example, with apps that add points and levels to `gamify’ a list of decontexualized facts or skills that students are required to master.”

Virtual reality involves immersion in the computer generated environment. In augmented reality, additional information is displayed on top of person’s real view. The Oculus Quest 2 has a pass through feature for augmented reality, used, for example, to set up the safety space. Wired has a good introduction to VR with explanation of some terms also.

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