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2016.12.02

Computer vs Human 0-1

Earlier today the Athens State Orchestra played the Symphony No. 3 in C minor, Op. 78 by Camille Saint-Saens, which is also known as the Organ Symphony. The French organist and composer Thierry Escaich was supposed to play the organ. There was a slight delay at the beginning: a lady appeared on stage and explained that there were technical problems with the organ's "brain".

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2016.05.07

The Computer Tube

I've been reading the book ENIAC in Action, which details the fascinating ten-year history of the first general-purpose programmable electronic computer. In it I found a reference to 7AK7, the so-called computer tube, which improved the reliability of tube computers.

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2015.12.13

Raspberry Pi vs USB vs Mac Audio

The audio hardware of Raspberry Pi is known to produce relatively poor sound quality. I bought a cheap USB sound card to try as an alternative. Here is what I found.

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2015.11.29

Raspberry Pi Zero vs Elliott 405

Twitter users @SadHappyAmazing and @HistoricalPics posted yesterday two photographs (copy) showing the Raspberry Pi Zero juxtaposed in front of the Norwich City Council Treasurer's Department building, where the delivery of the Elliott 405 computer was photographed in 1957. Here is how the two computers compare.

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2013.06.13

How to make a MacBook Kensington Lock Adapter

Apple, in its infinite wisdom, has not included a Kensington lock slot in the current model of the MacBook Pro computer. Given the computer's price, desirability, and the fact that three people I know have had theirs stolen, I decided to build an improvised adapter that would allow me attach a Kensington lock to the computer. I realize, that the security offered by such a contraption is what my colleague Vassilis Prevelakis calls an "advisory lock", for Kensington locks can be easily picked or pried away. However, I think it might deter a casual thief who would snatch the laptop you've left unattended for a couple of minutes.

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2012.10.11

Virtualize Me

The virtual machine (VM) is the most dazzling comeback in information technology. IBM implemented a VM platform architecture in the late 1960s in its CP/CMS operating system. The company’s goal was to provide the time-sharing capabilities that its batch-oriented System/360 lacked. Thus a simple control program (CP) created a VM environment where multiple instances of the single-user CMS operating system could run in parallel. Thirty years later, virtualization was rediscovered when companies like VMware found ways to virtualize the less accommodating Intel x86 processor architecture. The popularity of Intel’s platform and the huge amount of software running on it made virtualization an attractive proposition, spawning within a decade tens of proprietary and open source virtualization platforms.

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2012.09.18

Research Proposal Becomes Reality

Eight years ago I submitted a research proposal for developing a tablet-based game platform for toddlers. Although the proposal was not accepted for funding, it's nice to see the idea becoming a reality through the unveiling of the Toys 'R' Us $150 Tabeo tablet for kids.

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2011.11.27

Using the HP 4470c Scanner Under Windows 7

Neither Hewlett Packard nor Microsoft Windows 7 offer native support for my HP 4470c scanner. Throwing a working scanner away to buy a new one only because some software was missing seemed like a waste, so I looked for an alternative solution. This is how I made it work using SANE, an open source framework for scanners.

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2011.09.11

Faking it

This column is about a tool we no longer have: the continuous rise of the CPU clock frequency. We were enjoying this trend for decades, but in the past few years, progress stalled. CPUs are no longer getting faster because their makers can’t handle the heat of faster-switching transistors. Furthermore, increasing the CPU’s sophistication to execute our instructions more cleverly has hit the law of diminishing returns. Consequently, CPU manufacturers now package the constantly increasing number of transistors they can fit onto a chip into multiple cores—processing elements—and then ask us developers to put the cores to good use.

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2011.05.29

Ten Lessons I Learned from Fixing my Laptop's Motherboard

A month ago I managed to break my laptop, by reversing the polarity of a universal power supply. The repair shop diagnosed the problem as a failed motherboard, and asked for €659 to replace it. I found the price preposterous and the notion of throwing away a motherboard for a single failed component ecologically unsound. Here is how I fixed the laptop on my own, and what I learned in the process.

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2009.08.20

HP-200LX Remote Control Hacks

All my friends know that for the past 15 years I've been semi-attached to an HP 100LX palmtop PC (recently updated to a 200LX) for my personal information management and many other tasks. The device is extremely versatile, sturdy, and flexible. Amazingly, after so many years of hard daily use, I still find new applications for it.

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2009.05.27

Revisiting the Antikythera Mechanism Emulator

Over the past few weeks I updated the Antikythera mechanism emulator I built in 2007. I was preparing for an invited talk on the subject, which I'll give at the 2009 USENIX Annual Technical Conference, and for this I wanted to include in the emulator the new findings recently published in Nature.

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2009.02.18

The Information Train

Experiment overview The Information Train is a scientific experiment that I presented at the Wizards of Science 2009 contest over the past weekend. The entry demonstrates how computers communicate with each other by setting up a network in which a model train transfers a picture's pixels from one computer to the other. You can find a video of the experiment on YouTube, and, if you're interested, you can also download the corresponding software and schematics from this web page.

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2008.12.22

No Blinkelichten, Please

A computer's flashing lights used to fascinate me. They showed me it was alive and offered me a glimpse on its innards. They also epitomized the hacker culture of the famous "Blinkenlichten" sign.

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2008.04.18

LTO Tape Drive Compression Considered Harmful

I used to think that tape drive compression was a silly marketing trick used by manufacturers to inflate the advertised capacity of their tape drives. Apparently it is worse than that.

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2007.01.15

Landscape vs Portrait Monitors

Laptop monitors keep getting wider and wider. What I would really like would be for them to get higher.

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2006.12.25

The Capacitor Plague Hits a Baby Monitor

Good baby monitors are hard to come by. Many tend to be oversensitive, others switch from squelch mode to transmission with a loud hiss that is more irritating than a baby's cry. We were very satisfied with a Tomy Walkabout Digital 1998 baby monitor, until the day it started emitting a squeaking sound.

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2006.12.01

(Not) Hacking the Digipass Go 3 OTP Dongle

My bank moved to two factor authentication solution, and thus required me to purchase from them a Digipass Go 3 dongle in order to authenticate my transactions. To register my dongle I keyed-in a five-digit code they gave me, and also the key's serial number appearing on its back. Given that Go 3 utilizes an open authentication framework, and a published algorithm for generating the one time password (OTP), could I utilize the key and the numbers I keyed in, for using the key in my own applications, of for cloning the dongle in my mobile phone or palmtop?

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2006.07.11

Boot Lock

I first admired this ingenious method of locking a car in Rowan Atkinson's Mr. Bean series. A few days ago I saw it in real life.

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2006.01.03

Disappearing Hardware

Let's start the new year with a retrospective look at hardware advances. I've ordered some older and current hard disks that were lying around by date. We're taking for granted the increases in disk size, but also impressive is the reduction in size of the control electronics.

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2005.10.14

MIT's $100 Laptop

The MIT Media Lab is working on a research initiative to develop a $100 laptop. This will be distributed through governments to schools to help the education of the world's students. These are my notes from a talk Michail Bletsas, Director of Computing at the MIT Media Lab gave on the subject, at an event organized by the Netmode Laboratory .

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2005.10.04

Hard Disk Failure

I tell everybody that the question is not whether your hard drive will fail, but when it will fail. My laptop's drive started emmitting a loud grinding sound last Saturday.

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2004.12.13

Lack of Progress in Palm Applications

An article in slashdot recently discussed the limitations in the current breed of Palm handhelds. I am glad somebody has pointed out the lack of progress in the palmtop market. My 12-year old HP-100LX is literally falling appart, yet I can not find a worthwhile replacement.

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Unless otherwise expressly stated, all original material on this page created by Diomidis Spinellis is licensed under a Creative Commons Attribution-Share Alike 3.0 Greece License.