skip to main content - dyslexic font - mobile - text - print

Hacker Public Radio

Your ideas, projects, opinions - podcasted.

New episodes Monday through Friday.


Latest Shows


hpr1601 :: Howto Install LAMP

Klaatu introduces new web developers to LAMP.

Hosted by klaatu on 2014-09-22 and released under a CC-BY-SA license.
Listen in ogg, spx, or mp3 format. Comments (1)

If you're just starting out as a web developer or designer, you should know about LAMP and how to use it. This episode introduces you to the basics.

LAMP (software bundle)
From Wikipedia, the free encyclopedia
LAMP is an acronym for an archetypal model of web service solution stacks, originally consisting of largely interchangeable components: Linux, the Apache HTTP Server, the MySQL relational database management system, and the PHP programming language. As a solution stack, LAMP is suitable for building dynamic web sites and web applications.
https://en.wikipedia.org/wiki/LAMP_%28software_bundle%29



hpr1599 :: Interview with Ingmar Steiner from the MaryTTS project

Ken interviews Ingmar Steiner from the MaryTTS text to speech project.


Hosted by Ken Fallon on 2014-09-18 and released under a CC-BY-SA license.
Listen in ogg, spx, or mp3 format. Series: Interviews | Comments (2)

In today's show Ken interviews Ingmar Steiner who is the lead developer for the mary text to speech project. MaryTTS is an open-source, multilingual text-to-speech synthesis system written in pure java and is released under the LGPL. During the interview we get a history of the project, and dive into speech synthesis and we look at how to make your own voices.

Photo of Ingmar sitting on a rock in a pine forest with eyes focused on his grey mac laptop

Links


hpr1598 :: Hashing and Password Security

Understanding password security begins with understanding hashing.


Hosted by Ahuka on 2014-09-17 and released under a CC-BY-SA license.
Listen in ogg, spx, or mp3 format. Series: Privacy and Security | Comments (2)

Today, the most common way of providing security in giving access to data or systems is through the use of passwords. Practically every online site now expects you to create an account with a password, which will let you post comments, order products, conduct business, or just post to social media. The implication is that insisting on passwords provides some level of security. Now, following on our last tutorial we should ask a few questions about just how effective this measure is, since someone posting in your name to Twitter is significantly different from someone accessing your bank account. And since the assets being protected are very different, it would be reasonable to approach the problem of security somewhat differently in these cases. But given the ubiquity of passwords as the authentication for online accounts, we need to look at the security involved. Note that I am approaching this from the standpoint of the owner of the site in question for this tutorial, and will follow up with a look at your own role in this. - For more go to http://www.zwilnik.com/?page_id=640

Links:


hpr1597 :: Extravehicular Activity

NASA guidelines for EVA from spacecraft are detailed and painstaking, not so films.


Hosted by Steve Smethurst on 2014-09-16 and released under a CC-BY-SA license.
Listen in ogg, spx, or mp3 format. Comments (0)

EVA - The Rules for Extravehicular Activity

Here I dip into the NASA experience of and rules for Extravehicular Activity, prompted at first by watching a film called The Europa Report, directed by Sebastian Cordero (2013).

WARNING - THIS PODCAST CONTAINS SPOILERS

While I have some gripes about the film, I was impressed by its general failfulness to the science

  • It thought to find life on Europa, a moon of Jupiter considered by real exobiologists and planetary scientists to be a good candidate
  • Neil deGrasse Tyson made a cameo appearance
  • The portrayal of Europa's geography and character
  • Having to drill through the ice to get at the sea below
  • The behaviour of the crew as scientists and engineers

Science consultant on the film was Kevin Hand, an astrobiologist and expert on Europa at NASA's Jet Propulsion Laboratory

To my mind, the scientists were behaving like scientists and the engineers behaved like engineers. To follow along it might help to recall their names

  • Captain - Willam Xu
  • Pilot - Rosa Dasque
  • Chief scientist - Daniel Luxembourg
  • Marine biologist - Katya Petrovna
  • Junior engineer - James Corrigan
  • Chief engineer - Andrei Blok

All was going scientifically until the director drove the plot forward with two EVA incidents

EVA-1 : Flash back episode, engineers James and Andre go out to fix a failed communications circuit

  • Andre rips his suit
  • James gets squirted with rocket fuel
  • Only one astronaut survives

I have problems with this becuase it's just too clumsey for trained professional astronauts. Where are the decontamination procedures, the tethers, the special tools?

EVA-2 : Down on the surface, Marine biologist Katya decides to walk out alone

  • Tourtured debate in the ship
  • Of four able and expendable crew members, none go with her
  • Katya does not come back alive

With this I am shouting at the screen "No Way! Where's the fracking operating manual? No one goes EVA on their own"

So, that is why I researched the NASA rules for Extravehicular Activity. And I found that none of these events would have happened the way they were shown, had the crew, who were so professional in every other way, followed the NASA procedures.

The two astronauts issue

  • The most recent occasion where an astronaut went solo EVA was in 1971, when David Scott stuck his head out of the airlock of Apollo 15.
  • Most recent before that was in 1966, when Buzz Aldrin went EVA from Gemini 12 (Gemini craft only had two crew).
  • Since 1971, there have been 358 space walks and every single one has had two crew.
  • I found no written regulation, but de-facto, nobody leaves the spacecraft alone.

NASA procedures

NASA documents on the internet discuss in exhaustive detail all condiderations for EVA. What I present is a cherry-picked handful. I could not cover all of it

  • reasons for EVA
  • alternatives
  • planning
  • hazard mitigation
  • procedures for safe conduct
  • fall-back procedures
  • failure handling
  • accident control

International Space Station (ISS) EVA Procedures Checklists

  • Presuming that all the equipment maintenance checks, and readiness checks have alread been done
    • 30 minutes of Airlock preparation and testing
    • 30 minutes of changing components for the suit to fit the astronaut
    • 170 minutes of EVA-Prep
  • Then you are ready to depressurise and leave the airlock
  • EVA might last 2 - 8 hours
  • Post EVA
    • 30 minute procedure to take the suit off
    • 10 minute procedure to disconnect internal equipment
    • Recharge & maintain the Extravehicular Mobility Unit (EMU)
    • Clean & maintain the Suit

Although this podcast is about EVA, it does reference the science in a film that I enjoyed and respect very much, so here is a gem that I only came across while researching the landing site. In the scientific journal Nature, Volume 479, 16 November 2011, Britney Schmidt et al, of University of Texas, Austin, published a paper titled "Active formation of 'chaos terrain' over shallow subsurface water on Europa." In the paper these authors suggest that in the Conemara zone of the Chaos Terrain, an area on the surface of Europa, the ice may be as little as 3 km thick. Then in the film the Conemara Chaos was the targetted landing zone and the drill broke through the ice at a depth of 2800m.

Well there is one more thing that the podcast says, but it is the ultimate spoiler. So if you have not already listened to the podcast, I highly recommend that you watch the film first.


Links



hpr1595 :: 37 - LibreOffice Calc - More Financial Functions

A look at financial functions and constructing a mortgage repayment schedule


Hosted by Ahuka on 2014-09-12 and released under a CC-BY-SA license.
Listen in ogg, spx, or mp3 format. Series: LibreOffice | Comments (0)

We take a look at a number of related financial functions in this episode, and discover that they are strongly related by using the same variables over and over. We construct a Mortgage Repayment Schedule, and look again at the principles of good spreadsheet construction.


hpr1594 :: Steam and wine with linux

How to coax a windows-only steam game to work under steam in GNU/Linux.

Hosted by Andrew Conway on 2014-09-11 and released under a CC-BY-SA license.
Listen in ogg, spx, or mp3 format. Comments (3)

This isn't about my worshiping of Bacchus by playing games on linux in a sauna (that's for a future show) but instead about getting a Windows-only Steam game to work on a recent 64 bit linux distro. I'm using Slackware, but I suspect the pitfalls and solutions I encountered would be similar on other distros.

Links relevant to this adventure:


hpr1593 :: Why C++?

Introduction to the C++ programming language main features

Hosted by garjola on 2014-09-10 and released under a CC-BY-SA license.
Listen in ogg, spx, or mp3 format. Series: Programming 101 | Comments (1)

In this episode, Garjola presents the C++ programming language by introducing its main features for object orientation, generic programming and functional style.


hpr1592 :: An Open Source News Break from Opensource.com

Open source CMS, tools for making presentations, WikiProject Med

Hosted by semioticrobotic on 2014-09-09 and released under a CC-BY-SA license.
Listen in ogg, spx, or mp3 format. Series: NewsCast | Comments (0)

In this episode: Open source CMS applications go head-to-head, open source tools for making presentations, and WikiProject Med.

Links: