This new book is smaller, has fewer projects, requires the purchase of fewer components, is an accordingly less expensive book, and perhaps most important for some people, requires no solder! Continue reading A Beginner’s Guide to Circuits→
The number of satellite circling the Earth right now is approaching 5,000. The number that are not broken, and are being actually used, is just over 1,000. However, Space X, Elon Musk’s megacompany, is approved to launch well over 10,000 satellites over the next several years, to serve a single purpose: Give broadband internet to every human on Earth no matter where they are. Continue reading How many satellites are there, and will there be?→
You know all those projects where you wire up some electronic circuitry and then hook it all to a bunch of LEDs, then you have fancy or fun lighting? Like a Halloween costume, or a Griswald house, or some nice mood lighting in your home?
It is harder than it looks, though doable if you have a soldering iron and some basic electronic knowledge. The RocketLife project, which is starting a kickstarter any day now, claims to make this much easier.
The LEGO Boost Creative Toolbox is a humanoid robot that is also a guitar, a dogbot, and an industrial fabrication machine. Which of these things it is depends on which set of instructions you follow. A scratch-like programming language lets you control the boost from a phone or tablet, via blue tooth. It is not cheap, but it is an amazing and excellent toy.
This is not a book that fully explores the alliance and overlap between war and makers of war on one hand and science and scientists on the other. Authors Neil deGrasse Tyson and Avis Lang focus on one part of that relationship, the link between astrophysics and related disciplines (really, astronomy at large) and the military.
Back when I was working in or near the Peabody Museum, in Cambridge, the museum’s assistant director, Barbara Isaac, hired me to work with the NAGPRA database. NAGPRA was the North American Graves Protection and Repatriation Act. Ultimately, large swaths of the Peabody Museum’s collection would be turned over, or some other thing done to it, as per the wishes of the various Native American groups associated with that material. Most of the work had already been done. But, Barbara is a meticulous person and wanted to make sure the dotting of each i and crossing of each t was double checked. So, I was one of two people charged with going over the printouts, on that old green and less green striped paper, bound in large blue cardboard books. Each line (or two) was an item or collection of items, with notes, and an indication of what was going to happen to the material. There were just a few options, but the basic idea was this: An item listed was either going to be returned to a tribal group, or not. My job was mainly to look at stuff that was not going to be returned and, given my ongoing scan of what was going to be returned, and my knowledge of North American prehistory, ethnography, and archaeology, to earmark things that said “do not return” but where maybe we should be returning it. So, for example, after noting that a particular South Dakota Lakota tribe would have this, and that, and this other, soapstone tobacco pipe returned to them, when I saw that the ninth pipe on the list, several lines down and all by itself, is labeled to not be returned, I’d earmark that. Nearly 100% of the time, that ninth pipe was just something that nobody wanted, or it didn’t really exist (not all museum databases are exactly accurate). But, it would be earmarked.
Many items on the list had information as to how the item had originally gotten to the museum.
Many, many items, especially items taken from Native Americans living in what was the frontier between about 1840 and 1900, were taken by medical doctors who, as we all know, also stood in for naturalists, or some kind of traveling scientist, on military and quasi military expeditions (Like Darwin).
And many of those items were taken for use as medical specimens.
We initially learned that Native Americans have a particular blood type because, in part, of studies done on blood stains on shirts of slain warriors, collected after various battles with the US Army units accompanied by such scientists. There are a few famous cases of Native American bodily remains, mostly but not all skeletal remains, sitting in the anatomy teaching rooms of this or that college. But a lot more, a lot not noticed by either historians or even the all seeing all knowing Wikipedia, are or were sitting in museums around the world. Collected, by scientists wearing military uniforms, on military ventures, with a scientific twist.
So the science-military link is not exclusive to astronomy and astrophysics.
I wrote elsewhere about the person I met who was taking Pentagon funding to build an object that would help cure cancer. An example of a scientist subverting the military funding process. And so on.
OK, my complaint.
The authors have two long chapters (and references elsewhere) covering the early history of human endeavor in general (not limited to military) and the evolution of astronomy, mainly as it related, over a very long period of time, to navigation. One chapter covers land, the other the sea.
Staring somewhere along the way in each chapter, we get a very nice, well done, and pretty full description of the process of humans learning about the stars, about the earth and how to find one’s way, etc. But prior to that, the authors do what so many authors do and I so much dislike. I’ve written about this before. We get a version of human prehistory, and indeed, current human variation (or at least, ethnographically recent), that is bogus. For example, the authors speak of the first modern humans wandering around in the Rift Valley of Africa. There is no evidence that modern humans evolved there. Using just the archaeology, southern Africa is a more likely origin, and the physical anthropology record is simply incomplete. There are early fossils there, but that is because the rift valley is and was a big hole that made fossils. The entire rest of the continent is big, and the evolution probably happened there, not in the rift.
Similarly, ethnographic variation we see in the present and recent times is stripped out. For example, most rain forest dwelling foragers are not known to have a sky oriented cosmology, or to use the sky for much information about seasonal change in ecology, or navigation. And, there have always been a lot of rain forest dwelling foragers.
MIT Technology review has a fascinating writeup on efforts to build electric planes. In my view, these efforts are at the same time shooting too low (the result would be the equivalent of flying short buses, at most) and possibly doable (which is good).
Have you ever noticed how much electricity weighs? Here is an experiment you can do. Get two identical alkaline batteries (small ones, like AA size), one totally discharged and the other fully charged.
Now, hold one in each hand and see if you can tell which one is heavier. Is the charged up one heavier?
No, of course not. Electricity stored as potential energy in a battery actually weighs nothing. This is an interesting idea. Airplane fuel does weigh something, but electricity itself does not. If only we could create a battery that weights almost nothing to carry all that weight-free electricity!
OK, now, while you are still holding the batteries, try something else. Do this quickly, because you don’t want anyone asking you “why are you holding these batteries” right now, because you’d have to say, “I’m trying to see how much electricity weighs,” and that is kind of a stupid question.
Hold the batteries over a hard surface that you don’t mind dropping a battery on. Maybe ten inches to a foot above the surface. Hold them upright. Now, drop them on the surface and see how they act.
The “full” battery, the one with the charge, will normally bounce better than the “empty” one.
After reading this, I had this thought: Have a relatively small battery i an aircraft that does not use the same exact technology as the long distance battery, and is good at ONLY rapid output of a lot of power, and is replaced and recycled after every flight. Ideally, the plane would actually drop the battery once it is done using it. Neighbors of airports may object.
How to erase specific autosuggested URLs from Google Chrome?
You know the problem. You are accustom to swooping into the URL entry space on your browser and typing the first three or four letters of a website you commonly visit, hitting enter, and getting where you need to be. But Google Chrome, it an undying effort to be as helpful as possible, starts suggesting subpages of that site you visited once before, and are unlikely to visit again, ever.
For example, you want to look for something on Amazon. So you type in “Amaz” and suddenly the correct URL comes up, you hit ENTER and there you are. That is how it used to be. But now, you type “Amaz” and hit enter and you are now looking at an entry for a specific light switch you searched for last week. Forever. From now on, all of your searching on Amazon will start with this one light switch.
How do you stop this madness?
Simple: Once the URL you don’t like is visible in the search bar, use the down arrow key to put the focus on that very same URL down on the list that will also appear below the search bar. Then, use Shift-DELETE to eliminate that URL forever. Or any others.
Shift-DELETE simply removes that URL from your search history. Don’t worry, it will not delete that actual web site or anything. Totally safe.
Some of the earliest LEGO sets were for buildings or some sort of structure, and to this day architecture forms a core part of the LEGO panoply. If you build an architecture project from a kit, you’ll see that they are highly engineered. In order to make a LEGO project look like something other than a concoction of random bricks made by some kids having fun (which is, of course, just fine), serious planning has to have happened.
Most of the LEGO books I’ve seen are pure idea books. If you wanted to build a project based on what you see in the books, you have to either have a huge collection of LEGO parts very well organized, or you have to be prepared to order several specific bricks that are called for in the books.
But that is the wrong way to play with LEGOs. The books demonstrate concepts, give you ideas, guide you to become a better LEGOer.
How does this work? Let me give you an example. Say you want to build a building with nice columns. There are many different kinds of columns out there in architecture land, and you can imagine that there are different ways to build each one, and which method you use depends, in turn, on the scale you are working on. Say you want to build columns that would go with a building that would work well with the assumption that the building will be used by minifigs (the small LEGO people that come with many kits). Finch gives you sixteen pages of ideas for columns, starting out with these two:
The wizzard behind the book, Alice Finch, is one of the top LEGO builders in the world, famous for her extensive renditions of Harry Potter’s world and other major projects (see below). This is a great book for the aspiring LEGO builder, and an excellent choice as a holiday gift for your LEGO-loving offspring.
First, let’s get this one thing out of the way. How do you pronounce “SQL.”
Donald Chamberlin, the co-developer of SQL, pronounces it by saying the letter out louse. Ess Cue Ell. However, many computer science teachers prefer “sequel” and in at least one poll, the latte won out. One of the most common implementations of the database language is mySQL, and that piece of software is officially pronounced “My Ess Cue Ell” and not “Mysequel.”
I myself have never once uttered the word “sequel” when referring to this database system. I have also never once uttered either the term “Jiff” or “Giff” in relation to *.gif files. They are, to me, “Gee Eye Eff” files. I admit, however, to calling *.jpg files “Jay pegs” even when they are not *.jpeg.
But I digress. We are here to talk about a new book, on SQL.
The book provides what you need to know to create databases and set up relationships. But don’t get excited, this is not a dating book.
See, a “database” isn’t really a thing, but a collection of things. Normally, at the root of a database is a set of tables, which look like squared off sections of spreadsheets, or highly organized lists, if you lay them out. But then, the different fields (columns) of the tables are related to each other. This is important. Let’s say you have a table of individuals in your club, and each individual has a set of skills they bring to the table. It is a model railroad club, so you’ve got engineers, artificial vegetation experts, landscape sculptors, background and sky painters, and so on. Also, each club member has a known set of days of the week and hours that they are available to meet or to manage some event you are having. Plus, they each have lunch food and drinks preferences for when you order out. Three of the members drive wheelchairs. And so on.
You have a table of dates and times that will be when your club will meet over the next year. You have a list of venues you will meet in. Each venue is associated with a different deli where you order out. Some of the venues are not wheelchair friendly, while some are.
Imagine putting together a big chart that shows all the events, who is going to them, what everyone will eat, what everyone will do, and special needs requirements, for the next ten years.
If that was one single giant structured table, each time a given member was included on a sublist because he or she, there would also be all the information about the person’s address, phone number, email, food preference, skill, etc. etc.
So you don’t do that. Instead, the database is taught to associate the name of each member with that member’s personal file, including all that personal information, in a way that lets you selective ignore or include that information. Then, the database lets you construct new, novel, virtual tables that combine the information in a clever way.
For instance, for an upcoming event, you can have a to-do list that includes which materials to order for a build of a new model, and whether or not the person who helps Joe with the wheelchair thing should be sent a note to remind him to definitely come, and a precise list to send to the corner deli, as well as the phone number of the deli, for lunch, and so on.
Tables, linked together with relationships, which are then mined to make these novel tables which are called queries.
You may need to import data, export data, clean up errors, you may be using a GIS system, creating automatic emails or mail merge documents, and at some point you might even want to analyze the data.
The book assumes you are using PostgreSQL, which is free (and there are instructions to get it) but all SQL systems are very similar, so that really doesn’t matter too much.
Everybody who works with data should know some SQL. All desktop operating systems (Linux, MacOS, Windows) use this sort of software and it runs about the same way on all of them. Just so you know, you are using SQL now reading this blog, because SQL or something like it lies at the base of pretty much every common way of serving up web pages. Prior to you clicking on the link, these very words were in a database file, along with the name of the post, a link to the graphic used, etc. etc. A bit of PHP code accessed the data from the SQL database and rendered it into HTML, which was then fed to your browser. SQL is one of those things that lies at the root of how we communicate on line, and the basics of how it works and what you can do with it have not changed in a long time. The first relational models go back to 1970. Remember “dbase”? That was an early version, deployed in the early 1980s. By the mid 1980s, everything you can do with modern SQL, to speak of, was implemented.
A huge amount of energy is spent going to the store. The grocery store, the hardware store, all the stores. The amount of energy spent to get an object to the store for you to buy is big, but this process is on average highly efficient. A train can hold a lot of objects, and pushing a train down the tracks is highly efficient. Also, we will hopefully eventually be running trains entirely on a combination of electricity delivered to the train indirectly, batteries, and bio-fueled generators on board. Delivering object for you to buy at the store is already efficient, but it will become more efficient with a relatively small number of (big) step.
But then everybody leaves their home and drives various distances to various stores. When I was a kid, there were two grocery stores in our neighborhood. One had no parking lot, the other had room for about five or six cars, but nobody drove to either one. We used those two wheel carts you drag along to the store (or laundromat). When you get to the grocery store, you fold the cart up and hook it to a push car, then, when you pack up your groceries, they go in that two wheeler and you drag it home. Everybody did that all the time. It was strange to drive your car to the grocery store.
I remember when my parents started to drive to get groceries. Instead of going to the store on foot (or more likely, sending one of the offspring to the store with a list), they would drive out to the edge of town to a large warehouse discount store that had sprung up, like a Cosco. Oddly, large suburban style grocery stores emerged, in my world, after these edge-of-town discount store. My parents would drive the station wagon out there, spend all day, come back and and fill the freezer and cupboards. Maybe once every six weeks. In between times, for milk and other perishables that you can’t freeze, it would be walking to the A&P. So that was all pretty efficient.
But today, tens of millions of Americans get in a car and drive a few miles to pick up some object or bunch of objects at the stores. The energy spent to do that is large. The total amount of energy we spend going to the store to get objects is probably less than the total amount of energy spent to get objects from producers (via warehouses) to stores, but not by as much as you might think.
One way to solve this is to not go to the store in a car and by an object. Order it on line. The delivery will be more efficient. Or, in some cases, go to the store on foot, bike, or public transit, get your your stuff in a big pile, and then have the store deliver it to your house. And, have all the delivery done by electric vehicles charged with energy produced without fossil carbon.
I envision a future in which we abandon mail boxes and replace them with small rooms with an indoor and outdoor access, some insulation and modest climate control, a place to put frozen stuff, refrigerator stuff, other stuff. That’s where the grocery store delivery service drops your stuff.
Or, if you are in need of new flat packed furniture, Ikea:
In a couple of years, if you buy a Malm bed at Ikea in Brooklyn and opt for delivery, Ikea will probably drop it off in an electric truck. The company is transitioning to zero-emissions delivery in New York, Los Angeles, Amsterdam, Paris, and Shanghai by 2020. By 2025, Ikea aims to do the same for every store worldwide.
“Climate change is no longer just a threat, but it’s a reality,” says Jesper Brodin, CEO of Ikea Group. “We see how that impacts our business, our customers, and our coworkers more or less everyday . . . We want to be a leader, and take action, and speed up our plans.”
The company had announced earlier this year that it would shift to zero-emissions delivery by 2025, but now plans to work more quickly in key cities.
But where do you get one of those nice delivery receiving futuristic mail boxes with the climate control?