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Problems With Names, Part 2

Posted by cafebabe on Tuesday July 04 2017, @02:38PM (#2466)
3 Comments
Software

(This is the third of many promised articles which explain an idea in isolation. It is hoped that ideas may be adapted, linked together and implemented.)

How did we get to the current state of desktop computing and why is the future so uncertain? How did this veer so quickly into one of the deep topics of philosophy?

When Xerox PARC was founded in 1970, object programming languages, arbitrary bitmap displays, vector graphic storage formats, laser printing and ubiquitous desktop computer networking had yet to be developed. The development of a kid-safe computer which was no larger or heavier than a pad of paper was a futuristic dream. Nowadays, it seems laughably quaint. Unfortunately, continuous reference to paper has left us in a fascist dystopia of bureaucracy.

Our fundamental unit of information is not a bit, a factoid or a qubit. Our fundamental unit of information is a document, a form, a search, a sale or a recording. Unfortunately, with technology such as voice activated search, these units are often intertwined. In the broader case, this information is often used against a people who can or cannot be easily herded.

One future direction for technology is the full implementation of Ted Nelson's Project Xanadu. Ted Nelson is extremely irked by the current state of hypertext (a word he invented or popularized). However, his vision for orbiting satellites caching data paid with micropayments (another word he invented or popularized) remains outlandish after more than 40 years.

However, it is becoming less outlandish and is within the realm of tractable. Specifically, HTTP/1.0, as defined in RFC1945 reserved response code 402 for payment. When this was defined in May 1996, it was seen as a nod to our forefathers but with crypto-currency worth US$100 billion, implementation is a question which is being asked with increasing frequency.

It may be that Ted Nelson is fully vindicated and that the transition to DOI style tumblers and micropayments required a diversion via Zooko's triangle (however badly implemented). Prior to HTML and HTTP, hypertext was a knot of style, presentation, interface, content and transport. Systems such as Microsoft Help and AmigaGuide typically stored multiple documents in one annotated text file. HTTP/0.9 decisively cleaved storage, transport and presentation. However, it left a foreseeable trail of a trillion broken hyperlinks and an economic model which ate broadcast and print advertising.

If you've been following closely, you'll see that there are multiple possible formats for a reference to a resource. Typical formats include:-

  • foo://host.domain.tld/path/to/res.ext - URL.
  • bar:012345678abcdef - Hash of content.
  • baz:9.17.2.6.22-24 - Tumbler range.

Each has limitations. All function within a string namespace, although, historically, inter-operability usually fails. Ignoring this, questions remain. What do we wish to reference? How do we wish to reference it? (Source. Destination. Quantity. Frequency.)

There are further complications with references and I intend to describe them next.

Problems With Names, Part 1

Posted by cafebabe on Tuesday July 04 2017, @06:44AM (#2464)
2 Comments
Software

(This is the second of many promised articles which explain an idea in isolation. It is hoped that ideas may be adapted, linked together and implemented.)

Many of the limitations of computers occur because we have a poor simulation of paper popularized by a photocopying company.

However, there is another way. For this, I choose something which approximates a URL as a building block of information.

All problems in computer science can be solved by another level of indirection. -- Butler Lampson, Xerox.

By chosing a pointer in a namespace, we may reference legacy data (documents, multi-media files) in addition to data in the structure of our choice. If a URL, URN or URI was sufficient for this task then no further work would be required. However, a different approach is strictly necessary because:-

There are only two hard things in computer science: cache invalidation and naming things. -- Phil Karlton, Netscape.

In the current form, URLs, cookies and caching interact badly. For example, HTML requests made with different cookies cannot be shared among users. Whereas, image requests made with different cookies are handled as if the cookies were absent. This situation requires cache authors to implement a heuristic to ensure that most websites are compatible with one cache. Whereas, authors of popular websites implement a heuristic to ensure that most caches are compatible with their websites. The lack of fundamentals (no formal specification for URL caching) requires multiple parties to maintain complicated models. This is required so that a grammatically correct request for grammatically correct content behaves as expected.

A general problem with naming is Zooko's Triangle: Distributed, Secure, Human-Readable: Choose Two. However, even this would be an improvement. URLs incorporating DNS are not distributed. (DNS *servers* are distributed but a DNS namespace straddles one domain of trust.) URLs with or without SSL or TLS are not secure. 95% of users cannot read URLs.

Given an unconstrained choice, something like a Magnet URI would seem beneficial. However, this relies upon a chosen cryptographic hash function being a trapdoor function. If a practical quantum computer cracks the chosen trapdoor function then we have names which are neither secure nor readable. On the basis that security within a name cannot be guarateed, it may be preferable to err towards readable names and seek security elsewhere.

There are further complications with names and I intend to describe them next.

A Post-Xerox World

Posted by cafebabe on Tuesday July 04 2017, @05:14AM (#2463)
0 Comments
Software

(This is the first of many promised articles which explain an idea in isolation. It is hoped that ideas may be adapted, linked together and implemented.)

Someone from my makerspace said "We're living in a post-Xerox world." and he didn't mean Xerox's business of photocopiers.

The original objectives of Xerox PARC are in widespread use. That includes object programming languages, arbitrary bitmap displays, vector graphic storage formats, laser printing, ubiquitous desktop computer networking and - most notably - ruggedized, kid-safe computers which are no larger or heavier than a pad of paper.

He believes that we're in a malaise because we've reached a widely known goal and there is no agreed continuation. Actually, he believes the problem is more fundamental. Collectively, we don't know that there was a set of ideas popularized by one organization nor do we know that we attained it.

I believe that we have a different problem. We've implemented digital paper rather than digital computing. This would be a problem if it stayed in a computer but it often spills onto paper too. A word-processor and rapid printing is contrary to a paperless workflow. Most significantly, it has continued the trend of increasing bureaucracy and forms. Even in the 18th century, people complained that there were too many forms. Now we have forms on paper, in HTML, PDF, apps and elsewhere.

This is tedious. It costs time and money. There is the obvious cost of time spent completing a form and time spent by administrators to process a form. Many types of fraud can be achieved merely by completing forms. As an example, a dental fraud cost UK taxpayers £1.4 million (US$2 million). It was achieved by completing about 30 forms per day describing fictious dental treatment.

Bureaucracy is organized around institional memory. This may be quipu storage, filing cabinets, file servers or databases. Bureaucrats perform ingress and egress filtering. Both may be infuriating. Ingress filtering should ensure that institional memory is accurate but this rarely occurs when the cost of errors is externalized. For example, when hundreds of large companies have read/write access to credit checks, the majority of credit reports are wrong. Egress filtering should restrict disclosure of sensitive information but, again, costs are externalized. Obtaining any meaningful change of state may be difficult. Ensuring an accurate round-trip of data may be impossible. Likewise for any inter-organizational change of state.

Block-chain enthusiasts claim that smart-contracts will significantly reduce these problems. It could make inter-organizatioal state atomic. However, unwinding bad states may require an individual with the skills of a lawyer and a programmer. Furthermore, the reduced friction of transactions could make state changes more frequent. Essentially, by Jevons paradox, this encourages more bureaucracy. Meanwhile, the interface between person and bureaucracy may become increasingly quixotic.

Forms continue to proliferate without satisfactory user testing and each form remains an oblique signal for a bureaucracy to change state. That's increasingly irrelevant when nation-states are falling apart and corporations are increasingly untrustworthy. Indeed, while peons are completing each other's forms and contact each other in telephone call centers, our overlords collect data in bulk and transform it into structured data. The most benign example is marketing analytics for the purpose finding the local maxima of a business model. Another example is an opt-out, keyword aggregating marketplace which skims value from millions of parties. This is commonly called a search engine. Then there is the fascist, totalitarian panopticon of signals intelligence which treats every citizen as an enemy.

However, there is another way. It requires a more suitable building block of data. I intend to describe this next.

Budget Quadcopter Using $2 Audio Amplifier

Posted by cafebabe on Sunday July 02 2017, @01:13PM (#2458)
11 Comments
Hardware

This article has almost nothing to do with a promised series of articles. Instead, this is a continuation of motor control using audio amplifiers.

I previously discovered that a commonly available PAM8403 stereo audio amplifier board is sufficient to control two small motors. This is possible because the amplifier is intended to drive speakers with 4 Ohm or 8 Ohm windings. A speaker is a special case of linear motor and many small motors similarly have 4 Ohm or 8 Ohm windings.

The major advantage of this scheme is that *any* headphone output may be sufficient to control two motors. This includes pre-recorded sound or any programming language which can play sounds. That includes programming languages aimed at kids, such as Scratch and Squeak.

In some regards, a PAM8403 is an overkill for hacking. Regardless, it has advantages over an H-Bridge. For example, a linear amplifier allows forwards and backwards operation of two motors at variable speed. The major catch is that audio amplifiers expect an RTZ [Return To Zero] signal and therefore sending a continuous positive or negative signal fails to have any sustained impact. This can be overcome by sending a square wave of arbitrary amplitude and arbitrary duty cycle. A quirk of this encoding is that the square wave frequency isn't hugely important. We'll be using that property next.

A member of my makerspace asked if it was possible to control four motors using two audio channels. (Specifically, he's obsessed with quadcopters, drones and suchlike.) After some false starts, I found that an audio channel can be partially split into two by using an analog low-pass filter.

In this arrangement, the majority of an audio channel's amplitude is allocated to a low frequency square wave. This is directed to one pair of motors and allows the pair to be driven at almost maximum speed. The remainder of the audio channel's amplitude is allocated to a high frequency square wave which may have a complimentary or opposing bias. This is directed to one motor of the pair and provides stabilization of the platform in one axis.

For each audio channel, the audio filter consists of one resistor in series followed by one capacitor to ground. The product of the resistor and capacitor in the RC network determines the resonant frequency of the filter in radians per second. (Adjust by 2π to obtain cycles per second.) Optionally, use multiple RC networks in series to increase signal discrimination. However, for this application, it isn't particularly important.

Worked figures are as follows. Low frequency signal is 440Hz. Cut-off frequency is low frequency times four. High frequency signal is cut-off frequency times four. Resistors should be 470 Ohms. Capacitors should be 220pF.

I assumed that two stereo amplifiers would be required. By chance, another member of my makerspace was making an enclosure for stereo speakers and re-chargable batteries. The audio amplifier is a TDA7379 which is a quadraphonic amplifier which can be ganged into stereophonic. As a quadraphonic amplifier, it provides 13W per channel. I haven't gone through figures in detail but that should be sufficient to lift a computer, gyroscope and batteries. This is an extremely dangerous project but it is also shockingly accessible.

Difficulty With Collaboration?

Posted by cafebabe on Monday June 26 2017, @04:09PM (#2447)
15 Comments
Career & Education

I have difficulty collaborating with other people. It may be that I'm a cantankerous curmudgeon but I suspect this is (also) a wider problem.

I write software. I dabble with analog and digital electronics. I do computer system adminstration and database administration. I prefer to write in C (for speed) and Perl (because the interpreter is everywhere). I greatly prefer to avoid proprietary environments. Although I've been described as being to the left of Richard Stallman, my interest in open licences comes primarily from not being able to use my own work. (Others take a much more hard-line approach and refuse outright to work on anything which won't be GNU Public Licence.)

I'm willing to work almost anywhere in the world. I'm willing to work with micro-controllers, super-computers, Lisp, PHP, bash, Linux, BSD, ATM, SPI, I2C, CANBus and numerous other concepts. I prefer to work with content versioning (any is better than none) and repeatable processes. However, I'm willing to work in an environment which scores 4 out of 12 on the Joel Test.

I have difficulty getting enthused about:-

  • "Apps" where Apple or Google take 30%. This isn't a good deal for me or many clients.
  • node.js or other JavaScript - especially in conjunction with robot control.
  • C++, C#, Objective C, D or any other derivative of C.
  • Anything over radio - especially IEEE802.15.4
  • Block-chain systems in their current form.
  • Facial recognition.
  • Neural networks.
  • "User experience."
  • "Cloud."

I'm more enthused about FPGA and GPU programming but I like to have an abundance of hot-spares and, for me, that significantly increases a barrier to entry. This hardware also makes me edgy about being able to use my own work in the long-term.

Within these parameters, I'd like to describe some failed explorations with other techies. Without exception, I first encountered these techies at my local makerspace.

One techie is a huge fan of Mark Tilden, inventor of the RoboSapien and numerous other commerialized robots. Mark Tilden has an impeccable pedigee and has been featured in Wired Magazine and suchlike over 20 years or more. Mark Tilden espouses a low-power analog approximation of neurons with the intention of the neurons forming a combinatorial explosion of resonant states. When implemented correctly, motor back-EMF influences the neurons and therefore a robot blindly adjusts its (resonant) walking gait in response to terrain.

Anyhow, my friend was impressed that I'd used an operational-amplifier as an analog integrator connected to a VCO [Voltage Contrlled Oscillator] for the purpose of controlling servo motors without a micro-controller. My friend hoped that we'd be able to make a combo robot which, as a corollary, would perform a superset of 3D printing functionality without using stepper motors or servo motors. This is fairly ambitious but it would be worthwhile to investigate feasibility.

To complicate matters, I'm in a situation where modest financial success in this (or other) venture would gain my full-time attention. Whereas, he's currently receiving workman's compensation due to an incident at his electro-mechnical engineering job. So, I have every reason to commercialize our efforts and he has exactly the opposite motive.

There's also the scope of robot projects. They tend to be fairly open-ended and this in itself is cause for project failure. Therefore, I tried to nudge my friend into a project with a well-defined scope, such as high-fidelity audio reproduction. It is from attempts to make this situation work that I found that PAM8403 audio amplifiers were ideally suited to control motors. However, this discovery and further discoveries around it have not enthused my friend. (Note that the specification, as it exists, was to make an analog robot and avoid the use of stepper motors or servo motors. Admittedly, this fails to incorporate back-EMF but it is otherwise satisfactory.)

He's had personal problems which include his cheating Goth girlfriend dumping him and giving away his cat. He's also got his employer asking him to come back to work. Understandably, our collaboration has stalled.

An ex-colleague wants to collaborate in different projects. So far, we've had one success and one failure. The success contributed to a mutual ex-colleague's first Oscar nomination. The failure (his PHP, my MySQL) completely failed to mesh but led to a customized aggregator responsible for many articles on SoylentNews.

He's currently proposing an ambiguous deal which appears to be a skill-swap where we retain full rights on projects that we initiate. However, many of his projects involve tinkering with ADC and/or LCD. This would have been highly lucrative in the 1980s. Nowadays, it is somewhere between economizing and procrastinating. He previously worked on 100 Volt a monophonic valve amplifier but that was about three years ago and he never bothered to commercialize it.

Prior to this, I worked with friends on LEDs for an expanding market. We worked through the tipping point where the NFL and Formula 1 switched to LEDs. Two years ago, we were four years behind the market leader. Since then, we have completely failed to sell any LEDs to anyone. The majority have been using the venture for resumé padding and I've been out-voted on features even though I'm the only person who worked in the industry and worked with customers on a daily basis. After verbally being offered less than half of an equal share in my own venture, I haven't seen one of the active co-founders for 10 months. It would be reasonable to say that people are avoiding me. I find this bizarre.

Regardless, my task was to make a secure controller. The primary resumé padder wanted something which looked like an Apple TV. (This is for an industrial controller which may be exposed to 100% humidity and is required to meet ISO 13850.) I tried various options while being resource starved. I found that the software specification has yet to be achieved on a modern system. I found that the hardware specification is very difficult without an obscene budget. I also found that development on ARM has been difficult until relatively recently. The most accessible ARM system, a Raspberry Pi, didn't gain hardware floating point support under Linux until May 2016. Parties with successful projects (mostly phones) like these high barriers to entry. (How did Cobalt Networks launch successful RISC products in 1998? By using MIPS rather than ARM - and then switching to x86.)

In recent discussion about Raspberry Pi usage, you'll see how I've been influenced over the last two years or so about long-term support, hardware and packaging, micro-controller code density and other matters. I've also added options for documentation and training. However, without aligned collaborators or sensible resources, I'm not progressing. I suspect others are in diverse but analogous situations. Do you want to collaborate?

Free Speech in the UK

Posted by turgid on Friday June 23 2017, @10:47PM (#2439)
6 Comments
Digital Liberty

I may have inadvertently tested the limits of free speech in England and Wales.

The road to Hell, as they say, is paved with good intentions. And if you've got nothing to hide, then you've got nothing to fear. Ha!

If you're going to give the morons space to be stupid, you must surely give space for everyone else to challenge, parody, question, lampoon...

You Americans are lucky that you have an explicit written Constitution.

Bake me a cake with a file in it.

Logic Puzzle

Posted by DeathMonkey on Friday June 23 2017, @06:24PM (#2438)
7 Comments
Code
Let's earn  a shoutout for Soylentnews here:  https://fivethirtyeight.com/features/can-you-drink-more-coffee-than-your-coworkers/

6   4   7
5   X   12
3   11  16
There is a very specific logic underlying the grid of numbers above, and X is somewhere between 1 and 14. What, specifically, is X?

Discuss answers in the comments and if we figure it out I'll submit it under the name SoylentNews.org.

Mod Banned for using that SPAM mod we JUST discussed!

Posted by DeathMonkey on Wednesday June 21 2017, @08:09PM (#2433)
38 Comments
Code

UPDATE: currently hugging it out

Message from the Buzzard: Sorry to have to issue another mod-ban but you know as well as anyone that garden variety trolling is not Spam after having already gone through this once before.

Did we Buzzard? Funny, 'cause you just said this recently: If your posts were topical they might be called satire but posting incoherent ramblings into unrelated stories is quite clearly Spam.

the comment in question

How is that not an incoherent rambling unrelated to the story??

Also, that's literally the only time I've used the SPAM mod so we haven't been through anything before.

FBI files on Gary Gygax

Posted by khallow on Friday June 16 2017, @02:03PM (#2418)
3 Comments
/dev/random
Apparently, the FBI in the mid 1990s was looking for connections between the role play gaming (RPG) industry and the Unabomer. As a bonus, they got this bit of nasty gossip from a TSR (Tactical Studies Rules, the publishers of the Dungeon and Dragons RPG) employee at the time on former founder, Gary Gyrax who had been kicked out years earlier from the company.

In the early 1980’s, GYGAX had been generating about $1 million per year in income. [Redacted] advised that GYGAX spent his money frivolously. GYGAX was involved in an unpleasant divorce and [Redacted] further advised that GYGAX was a drug abuser. GYGAX is approximately 55 years of age and is currently [redacted]. He lives on Madison Street in Lake Geneva, Wisconsin and may be contacted at (414) xxx-xxxx. GYGAX maintains a mailing address as follows: P. O. Box 388, Lake Geneva, Wisconsin. [Redacted] considers GYGAX to be eccentric and frightening. He is known to carry a weapon and was proud of his record of personally answering any letter coming from a prison. GYGAX set up a holding company in Liberia to avoid paying taxes. He is known to be a member of the Libertarian Party.

Oh dear.

Spam Mod

Posted by DeathMonkey on Wednesday June 14 2017, @05:24PM (#2411)
34 Comments
Code

Spam (Score: 2)
by The Mighty Buzzard (18) Subscriber Badge Neutral on Monday June 12, @03:40AM (#524232) Homepage

If your posts were topical they might be called satire but posting incoherent ramblings into unrelated stories is quite clearly Spam.

Aristarchus modded Spam (not reverted)
realDonaldTrump modded Spam (not reverted)

Sensing a bit of a pattern...

So when I start modding Eth Fueled as Spam those won't be reverted, right??