"Normal" accidents, or system accidents, are so-called by Perrow because such accidents are inevitable in extremely complex systems. Given the characteristic of the system involved, multiple failures that interact with each other will occur, despite efforts to avoid them. Perrow said that, while operator error is a very common problem, many failures relate to organizations rather than technology, and big accidents almost always have very small beginnings. Such events appear trivial to begin with before unpredictably cascading through the system to create a large event with severe consequences.
Normal Accidents contributed key concepts to a set of intellectual developments in the 1980s that revolutionized the conception of safety and risk. It made the case for examining technological failures as the product of highly interacting systems, and highlighted organizational and management factors as the main causes of failures. Technological disasters could no longer be ascribed to isolated equipment malfunction, operator error, or acts of God.
Perrow identifies three conditions that make a system likely to be susceptible to Normal Accidents. These are:
A test to see if ordinary LED lamps can be under-run like Dubai lamps to make them last longer with reduced intensity and heat.
To limit the current I used different values of series capacitor, which has a soft limiting effect, making it compatible with traditional capacitive dropper and linear regulator based lamps.
This technique does not work with some lamps with switchmode based power supplies. They will tend to strobe due to the way the circuitry works.
This project involves mains voltage, and suitable precautions should be taken during your experimentation.
The trickiest bit about making a Dooby lamp is finding a place to put the capacitor. In some capacitive dropper based LED lamps it's easy, since their covers may unclip allowing the original high value capacitor to be changed for a lower one. For other lamps like the glass filament styles the capacitor will need to be put inline external to the lamp. That could be in a lamp extender (if you can get one that is easy to open), in a ceiling rose, in the wiring box of a chandelier or in the lightswitch enclosure. Doing it at the lightswitch opens up the possibilities of letting the lamp be switched between full intensity mode or a lower security/night light mode. With two switches you could have the option of on, dim or off.
A benefit of using a capacitor is that it is a soft, efficient and low noise way of dimming to a fixed level. The power factor will generally be no worse than the original, and a suitably rated capacitor will be virtually indestructible in this application.
From my tests the following 400V AC capacitors worked well for a European 220-240V supply:-
470nF converted most lamps to approximately 2W
220nF converted most lamps to around 1W
100nF converted most lamps to around 0.5W
47nF was not measurable. Probably around 0.2W
22nF was not measurable. Probably around 0.1W
10nF (ceramic capacitor). Some lamps won't glow because they have an internal shunt resistor to avoid nuisance glowing due to capacitive switch-wire coupling. But others will glow at a surprising intensity for the tiny current. (I was really surprised at the intensity of some lamps.)
For 120V supplies the capacitors should be 250V AC film capacitors and the values may have to be higher - like 1uF or more. The capacitors are common and cheap, so they can be experimented with. They can be connected in parallel for higher capacitance.
I used a 1 Megohm resistor in parallel with the capacitors during my tests, as the capacitors can store a charge and may give a slight zap if not discharged. In final use the resistor can be soldered or twisted directly to the capacitor leads.
The capacitors will run cold and should be insulated properly if used behind switches or in junction boxes. That could be done with heatshrink sleeving.
Although the super low value capacitors like 22nF only made the lamps glow dimly, it makes them very suitable as directly viewed decorative lamps or for use as night lights, where very little light will be ample at night. With such low power the lamps can be left running continuously, as they will last a very long time and cost virtually nothing to run.
Time was when nobody knew, or even cared, exactly what time it was. The movement of the sun, phases of the moon and changing seasons were sufficient indicators. But since the Industrial Revolution, we’ve become increasingly dependent on knowing the time, and with increasing accuracy. Not only does the time tell us when to sleep, wake, eat, work and play; it tells automated systems when to execute financial transactions, bounce data between cellular towers and throttle power on the electrical grid.
The latest artificial intelligence systems start from zero knowledge of a game and grow to world-beating in a matter of hours. But researchers are struggling to apply these systems beyond the arcade.
As I have 20 GB of data per 30 day period or an average of 682 MB/day of data to use with my hotspot device I use at home for Internet during the winter months for work and play, I have to be careful on how much data I use. While I only used about 11 GB during the December 24 – January 23 period, it’s important that I be measured with my data use.
I wrote a short script to output my connection strength, 5-minute / 1 hour / 1 day data use and current top application using data that I display in the XFCE panel using gen-monitor. For example, this is the display:
Here is the PHP script I use to generate it — it’s a mix of PHP and BASH. I could have done it all in BASH but truth be known I’m lazy and I’m better at PHP coding.
I actually enjoy watching the meter and being careful with my usage. It forces me to be deliberate, and make sure I’m careful with the data I’m consuming, using my smartphone for video meetings and watching video. I am actually surprised how little data ordinary web surfing uses – it’s really the video and downloads that eats a lot of data – especially the big GIS files. But I can go to the library for such purposes.
While I don’t have a good count based on SSID, it looks like I used about 11.2 GB on the hotspot and 19.2 GB on wired networks, mostly at the library and some at my parents house, downloading videos for later watching, updating or installing Linux apps, and downloading large GIS files. Downloading Youtube videos for later consumption really is a big bandwidth suck.
I like the challenging of being aware of my internet consumption and being responsible about the amount of data I use each day.
I have been following the right-to-repair movement a bit. It seems silly that companies shouldn't be required to provide repair manuals and documentation for machines they release on the world.
Some further thoughts on computer technology in my life …
I grew up in the era of Napster and Macintosh System 7, I never liked the changes when they dropped support for classic Macintosh. Instead, I readily embraced Linux, which is more stable and rarely changes, at least if you don’t want to upgrade to the fancy window managers and desktop environments.
Linux does everything that I could ever need. Maybe because I don’t play games or have very specialized needs, I find that Linux really offers everything I could use for my needs. Maybe occassionally a MS Word document gets a bit mangled in translation but even that’s rare these days.
I don’t like commercial programs. Why pay for something you can get for free, plus have access to the source code and ability to modify the programs as need be through editing source code, or even just the configuration files and plugins? It’s also great that if you are curious how something works you can try to study the methods in the program via the source code.
I don’t like change. One of the great things about Linux is you can keep running the same Window Manager and programs forever, as old programs are usually ported forward as new to versions of Linux. Old programs often are often fast loading and if they did the task in the past, they can still do it today. For example, the XFCE Desktop Environment I use remains virtually unchanged from 25 years ago and is pretty similiar to Mac OS 8 or Winders 95.
I’ve never really wanted to learn gee-gaw Winders 10 or Mac OS X. It just seems like those operating systems have so much unnecessary clutter and window effects that provide no benefit to me. They seem to change their interfaces every two years, while Linux remains largely the same with the same stable roots of half a century ago, and the XFCE window manager being very similar for a quarter century.
I don’t mind not really knowing how to use Mac OS X or Winders. I think the last good version of Mac OS was System 7.5.3, after that things got too complicated and slow. Shortly after then I switched over to Linux in recent years I’ve been pretty much using the same basic software, with few changes. QGIS has gotten a lot more powerful and I’ve learned a lot about mapping, but that’s probably far out of the mainstream of computing today with all this smart crap I don’t use.
I like simple programs you can chain together. The classic Unix philosophy is that all programs should be small and modular. While that isn’t always true these days — QGIS and LibreOffice are rather big monolithic programs — you can chain those big berthas to smaller Unix commands. When you look at those big berthas up close they tend to be more reliant on smaller parts of Unix that might not always be apparent.
I like to tinker but I don’t consider myself a computer geek. I find a lot of the “high” technology things like Winders 10 and Mac OS X to be foreign, I don’t have a Firestik unless you consider the radio antenna on my truck to be Firestik. I don’t ever use Amazon and it’s been months since I’ve ordered anything from EBay.
I like electronics and building things with microprocessors, but you’ll never see me with one of those smart home devices. If I can program something with an Arduino or ESP32 microprocessor, that’s neat, but I can’t imagine ever owning one of Amazon Echos or smart light bulbs. I don’t have a permanent Internet connection at any rate.
To this day I refuse to have a wired internet connection at my apartment, although this winter I do have hotspot data through my phone which turns out to be kind of nice for light web-surfing and working on my blog — mainly because I need a reliable internet connection for work and the library is not open for in-person use during the cold of winter. Once the panademic is over, it’s back to walking down to park or library when I want to get on the web on my laptop.
I don’t mind having the Internet on my Smartphone, although I do worry about spending too much time scrolling through Facebook and Instagram. I have sworn off any kind of political comment on Facebook, and generally try to refrain from any comments on social media.
While I wouldn’t want to give up the Internet, I like keeping things simple and my use of it controlled and limited. It’s great for sharing ideas and photos, but I’d rather stay away from confrontational places like social media.
