All Postings (93)

2017

Computer Science and IT

Taking stock! Physics

Subversive? Physics?

My Philosophy!

Scripts Beget Scripts

2016

Theoretical Physics. A Hobby.

Self-Referential Poetry

Silent Online Writing

'Are You Still Doing PKI?'

My Philosophy (?)

Impact of physics on my life

Not much happened in 2015

2015

Unspeakable

Self-Poetry

Farewell Posting ...

Hacking away...

Web Project - Status

We Interrupt ...

Poetry from Poetry

PKI-Status-Update

Life and Work

Definition: 'Subversive'

2014 in Books

Physics Postings

Engineering Postings

True Expert

2014

2014 - a Good Year

Physics or Engineering?

Engineering Links

What Is Art?

Bio

PKI FAQ

Google's Poetic Talents

Certificates and Heat Pumps

Nr. 5: A Mind-Altering Experience

Technet postings

WOP!

Pink Spaceship

radices = Roots!

IT Postings

Web Projects

Life, the Universe, and Everything

Uh-oh, No Posting in March

PKI Resources

PKI Issues

Subversive Work

Spam Poetry

A Career 'in Science'

Writing

On the Shoulders of Subversive Giants

Search Term Poetry

Facebook Art

2013 in Books

2013

Explain, Evaluate, Utilize

Technology

About Life-Form Elke Stangl

elkement and This Site

No. 3: Internet Apocalypso

Retrospection

Newsletter Resurrection

2012

For Free

Subversive Yearly Report

Is My Life a Cliché?

Indulging in Cliché

Torture Turning Trivia

Intermittent Netizen

Knowledge Worker...

Profile

Physics on the Fringe

Graduation Speech

The Element is Back!

Offline

Physics Links

2011

Not Funny

Calendar and Magic

Expert

In Need of a Deflector

About to Change

A Nerd's Awakening

For the Sake of Knowledge

2008

Profession Or True Calling?

No. 2: On Self-Reference

I Have No Clue About Art

Netizen

2007

The End

No. 1: On Subversion at Large

2005

Emergency Exit

Modern Networker

2004

The Scary Part

Exploring the Work Space

2003

Instead of a CV

Favorite Books

2002

Elke was here

Postings tagged with 'Links', listed in descending order by creation date. All Postings shown.

Heat Pump System and Renewable Energy

(elkement. Last changed: 2015-11-07. Created: 2015-02-04. Tags: Postings, Blogging, Resources, Links, Engineering, Heat Pump. German Version.)

I blog about anything heat-pump-related, in particular about our system. In addition, I am interested in thermodynamics, heat pumps and heating systems in general - and their integration with the smart grid and related security concerns. These are my postings about our 'ice-storage-/solar-' powered system specifically and postings on closely related subjects like the power grid, renewable energy and sustainable living.

Hydraulic schema of our system

My Articles on IT Security, Monitoring, PKI.

(elkement. Last changed: 2015-11-07. Created: 2014-06-01. Tags: Postings, Blogging, Resources, Links, IT, Monitoring, PKI, Security, X.509, Cryptography. German Version.)

My lecture slides on PKI and security are a bit dated already, I add them for completeness though.

Articles on my blog are targeted to a broader audience - perhaps they are too 'philosophical' for security experts. See the complete list of postings below, after the image.

X.509 Certificate

Last link changed: Migration of classical CSP to CNG / KSP, and old but good MS overview on certificates for network authentication of devices.

PKI: Links and Resources

(elkement. Last changed: 2015-12-07. Created: 2014-03-04. Tags: Resources, Links, IT, PKI, Public Key Infrastructure, Security, X.509, Cryptography. German Version.)

This is my list of Links to white papers and the like that I have found useful (restarted 2014). It is not an attempt to create a balanced or educational list. I am adding what I need right now!

Comprehensive reviews of PKI issues

Analysis by Peter Gutmann who likes to throw rocks at PKI according to his bio:

Certificate validation

Request for Comments:

In Windows systems:

Cross-certification and hierachies

Certificate enrollment

Links for Microsoft's autoenrollment are provided in more MS-related sections

Weird, hacked, forged certificates

PKI planning

Somewhat Microsoft-centric:

Windows PKI: Features and management

After I started compiling my own list, I found this - I will keep picking some of the microsoft.com links and publish them to this page though:

Some of the features required to run a Microsoft PKI in a larger, corporate environment:

Windows PKI 2008 R2 versus 2012 R2 and upgrade of hash algorithms

New features in 2012! Note I started added some the detailed articles about specific features - NDES, templates - also to other sections. This section is for overviews covering many new features or cryptograpy / algorithms in particular.

New ways to leverage a TPM chip - key attestation by validation of an endorsement key. You could have used a TPM chip as a custom key store for the machine / SYSTEM in earlier versions of Windows (basically like a 'smartcard for machines) in case the vendor of the TPM chip or a vendor of crypto software provided a suitable CSP / CNG provider. Starting with Windows 8.1 as the end-entity's OS the CA (2012 R2) is able to check if the private key had really been stored to a TPM chip.

New algorithms:

  • Changing public key algorithm of a CA certificate - only the hash algorithm can be changed (for CNG providers), not the provider itself.
  • Upgrade Certification Authority to SHA256 - after the change of a registry key the CA signs anything with the new algorithm, including CRLs and its own CA certificate when renewed (Step-by-step-instructions).
    Attention - according to my experiences with 2008 R2 the registry value for hash values is case-sensitive. Good: The change of the hash algorithm can be reverted easily. Bad: This is a per-CA settings, so once the algorithm has been changed all certificates and CRLs issued by that CA are signed using the new algorithm.

Certificate and key stores

Windows client-side stores:

Encoding

Using certificates for authentication

Native Active Directory logon:

Webserver-based mapping (no directory)

Apple iDevices, SAP, and other non-MS clients

  • In contrast to Windows'/AD's native logon via UPN string mapping SAP uses a 1:1 mapping of binary certificates to users:
    Single Sign-on mit SAP (part of a German book, assignment of the certificate is explained on pp.33)
  • Apple iPhones, 802.1x authentication against Active Directory using Windows RADIUS server (NPS)
    (promoted to blog post, summary kept here for traceability).
    • Properties of the certificate
      Subject CN: host/machine.domain.com
      Subject Alternative Name machine.domain.com
      Certificate Template (Windows Enterprise PKI): Copy the default template Workstation Authentication, Subject Name: Name as submitted with the Request.
    • Create the key, request and certificate on a dedicated enrollment machine and export key and certificates as PKCS#12 (PFX) file.
    • Create a shadow account in Active Directory
      dnsHostName: machine.domain.com
      s
      ervicePrincipalNames: HOST/machine.domain.com
    • According to my tests, the creation of an additional name mapping (as recommended here) is not required - SAN-DNS gets mapped onto dnsHostName in AD.

Network authentication of devices

  • Overview: Certificates for different services / protocols, like 802.1x or IPsec

PKI Applications

Started in 2014-10. Usual suspects as SMIME, EFS, 802.1x to be added as needed over time. See also the list of Technet Postings and the PKI FAQ.

Useful commands (in the Windows world)

Configuration parameters:

Emergency processes, for Windows.

  • Delete cached CRLs:
    certutil -setreg chain\ChainCacheResyncFiletime @now
    (Weitere Optionen siehe diesen MS-PKI-Team-Blogeintrag)
  • Start a CA even if the revocation check on its own certificate has failed - set this flag:
    certutil –setreg ca\CRLFlags +CRLF_REVCHECK_IGNORE_OFFLINE
  • Key Recovery:
    • Search for the archived keys of a specific user and create a batach script (CA admin permissions required)
      certutil –getkey domain\username >recovery-username.bat
      This script also contains the password of the p12 key file that will be created.
    • Run this batch file. This creates a single p12 file including all keys for this user. Pre-requisites: The user executing the script needs to have one Key Recovery Agent's certificates associated with each of the keys to be recovered in his/her store. In addition CA Admin permissions are required and this needs to be an admin cmd session.
    • The batch file does the following for every key found:
      certutil -getkey [SerialNumber] [encrypted blob]
      certutil -recoverykey [encrypted blob]
      A temporary p12 file is created from every blob; then all p12 files are merged using
      certutil -mergepfx and all temporary files are deleted.

PKI and smart metering

Requirements for a smart meter PKI in Germany:
Sicherheitsinfrastruktur für „smarte“ Versorgungsnetze

An example: Smart Meter mit PKI Sicherheit

X.509 Certificate

Physics Links

(elkement. Last changed: 2015-02-14. Created: 2012-03-10. Tags: Physics, Links, Resources)

Here I maintain a list of physics books, documents, blogs, and lectures I read / watch or that I have put on the (virtual) bedside table.

The collection is not some carefully crafted, balanced list - I am not searching for resources to add them here but I add what is interesting to me as a professional or a dilettante science blogger. I apologize for the mixture of German and English resources, and the structure is always work in progress.

This list had been formerly curated on my blog, on a page called Physics Books on the Bedside Table. I decided to migrate these links over here as in 2014 I had started to curate all my tech / science links on radices.net.

Popular Science Books 'enthusiastic'

Popular Science Books 'critical' (Note: This is not 'Alternative science')

History of Science and Biographies of Physicists

Quantum Physics, Quantum (Field) Theory

  • Oersted Medal Lecture 2002: Reforming the Mathematical Language of Physics, as recommended here. Actually, this is about all of physics and how more powerful, concise, and elegant Geometrical Algebra would do away with concepts that just appear tacked on – as there is an underlying hidden structure. It is useful in classical physics but especially to understand the seemingly weird world of the complex wave function.
  • Lectures on Quantum Field Theory by David Tong. Videos of his lectures delivered at Perimeter Institute can be found here (different formats available). These lectures were my starting point for (re-)learning QFT having been exposed to mainly condensed-matter-related and non-relativistic quantum statistics and 'second quantization' 20 years ago.
  • Quantum Field Theory in a Nutshell, a concise textbook by Anthony Zee. David Tong highly recommends this book, saying tongue-in-cheek: He lies to you all the time, but in a good way. It is not an easy read because the presentation of the material is quite condensed. You have to fill a lot of intermediate steps in derivations. On the other hand this makes it a great book for serious self-study. It shows that Zee is a gifted writer of popular science books as well as his conceptual overviews are spot-on and very helpful for tackling the hard stuff.
  • I trust Graham Farmelo on this and put Stephen Weinberg's book on my To-read-list.
  • Student Friendly Quantum Fielf Theory by Robert D. Klauber. Klauber describes and writes out details in derivations, avoids all references to so-called trivial, obvious and easy steps, and he refers to his own learning QFT often. The book seems to have been written from the learner's perspective – he often anticipates those typical baffled student's questions and answers them before you dared to ask it. More praise in this post of mine.
  • A lecture on Quantum Field Theory in German, by Gerhard Soff. I like these lecture notes because topics are reviewed from different angles (such as: canonical quantization versus path integrals) and the derivations are done in detail for all the different options.
  • The Fun is Real. Blog author Warren Huelsnitz definitely meets his goal: to sort through the myths and misconceptions, and the excessive and misleading hype, associated with quantum physics.
  • An Island In Theoryspace – an awesome blog by Jaques Pienaar on physics (mainly of the quantum variety) and sometimes also on its interface with philosophy.

Quantum Computing and Quantum Cryptography

The first field that rekindled by excitement for physics in about 2003, having worked in IT already for some years.

  • wavewatching.net. A blog written by a physicist and IT consultant who tries to separate fact  from VC fiction and to predict what impact quantum computing will have on corporate IT.

Relativity

Thermodynamics and statistical mechanics

Fascinating water, water vapor, and ice

Fundamentals

Classics: Basics and fundamentals – books and blogs that cover all of physics

It is very interesting to compare Feynman's and Macke's books – they have been published at about the same time and might serve as good examples for both excellent, but different ways  to describe physics from scratch – 'American' versus 'German'.

  • A very detailed blog – physicspages.com – Physics Tutorials with lots of examples, introductions and the author's solutions to text book problems.
  • Scientific Finger Food: Sebastian Templ achieves his goal – quote from his About page: “I give my best to break it down into simple language. In doing so, I hope that I can serve you some pieces of physics, which I like to think of as being clear to me, in 'delicious and manageable bites' “.
  • motionmountain.net: Six volumes on physics, written by a physicist who works as an innovation manager. Probably the most professional hobby / moonlighting physics project I have come across.

Classical Physics

Classical (point particle) mechanics

Fluid dynamics

The Collector Size Paradox (2017-11-01 15:11:56)
Recently I presented the usual update of our system’s and measurement data documentation.The PDF document contains consolidated numbers for each year and month of operations: It is finally time to tackle the fundamental questions: What id the impact of the …

Data for the Heat Pump System: Heating Season 2016-2017 (2017-10-12 09:58:29)
I update the documentation of measurement data [PDF] about twice a year. This post is to provide a quick overview for the past season. The PDF also contains the technical configuration and sizing data. Based on typical questions from an …

Tinkering, Science, and (Not) Sharing It (2017-09-17 11:06:44)
I stumbled upon this research paper called PVC polyhedra: We describe how to construct a dodecahedron, tetrahedron, cube, and octahedron out of pvc pipes using standard fittings. … In particular, if we take a connector that takes three pipes each …

Simulations: Levels of Consciousness (2017-08-17 10:41:54)
In a recent post I showed these results of simulations for our heat pump system: I focused on the technical details – this post will be more philosophical. What is a ‘simulation’ – opposed to simplified calculations of monthly or …

Heat Transport: What I Wrote So Far. (2017-07-14 09:15:49)
Don’t worry, The Subversive Elkement will publish the usual silly summer posting soon! Now am just tying up loose ends. In the next months I will keep writing about heat transport: Detailed simulations versus maverick’s rules of thumb, numerical solutions …

Simulating Peak Ice (2017-05-02 08:43:17)
This year ice in the tank was finally melted between March 5 to March 10 – as ‘visual inspection’ showed. Level sensor Mr. Bubble was confused during the melting phase; thus it was an interesting exercise to compare simulations to …

Mr. Bubble Was Confused. A Cliffhanger. (2017-04-08 11:06:20)
This year we experienced a record-breaking January in Austria – the coldest since 30 years. Our heat pump system produced 14m3 of ice in the underground tank. The volume of ice is measured by Mr. Bubble, the winner of The …

Where to Find What? (2017-03-18 15:20:13)
I have confessed on this blog that I have Mr. Monk DVDs for a reason. We like to categorize, tag, painstakingly re-organize, and re-use. This is reflected in our Innovations in Agriculture … … as well as in my periodical …

Ice Storage Hierarchy of Needs (2017-02-22 17:30:10)
Data Kraken – the tentacled tangled pieces of software for data analysis – has a secret theoretical sibling, an older one: Before we built our heat source from a cellar, I developed numerical simulations of the future heat pump system. …

Earth, Air, Water, and Ice. (2017-02-05 11:48:33)
In my attempts at Ice Storage Heat Source popularization I have been facing one big challenge: How can you – succinctly, using pictures – answer questions like: How much energy does the collector harvest? or What’s the contribution of ground? …

Frozen Herbs and Latent Energy Storage (2017-01-20 13:48:10)
… having studied one subject, we immediately have a great deal of direct and precise knowledge … of another. —Richard Feynman Feynman referred to different phenomena that can be described by equations of the same appearance: Learning how to calculate …

My Data Kraken – a Shapeshifter (2016-12-22 10:53:56)
I wonder if Data Kraken is only used by German speakers who translate our hackneyed Datenkrake – is it a word like eigenvector? Anyway, I need this animal metaphor, despite this post is not about facebook or Google. It’s about …

And Now for Something Completely Different: Rotation Heat Pump! (2016-11-03 09:55:35)
Heat pumps for space heating are all very similar: Refrigerant evaporates, pressure is increased by a scroll compressor, refrigerant condenses, pressure is reduced in an expansion value. *yawn* The question is: Can a compression heat pump be built in a …

Same Procedure as Every Autumn: New Data for the Heat Pump System (2016-10-21 09:49:11)
October – time for updating documentation of the heat pump system again! Consolidated data are available in this PDF document. In the last season there were no special experiments – like last year’s Ice Storage Challenge or using the wood …

Re-Visiting Carnot’s Theorem (2016-09-18 10:09:51)
The proof by contradiction used in physics textbooks is one of those arguments that appear surprising, then self-evident, then deceptive in its simplicity. You – or maybe only: I – cannot resist turning it over and over in your head …

Hacking My Heat Pump – Part 2: Logging Energy Values (2016-08-24 09:52:12)
In the last post, I showed how to use Raspberry Pi as CAN bus logger – using a test bus connected to control unit UVR1611. Now I have connected it to my heat pump’s bus. Credits for software and instructions: …

Hacking My Heat Pump – Part 1: CAN Bus Testing with UVR1611 (2016-08-03 10:04:39)
In the old times, measuring data manually sometimes meant braving the elements: Now, nearly all measurements are automated: In order to calculate the seasonal performance factor of the heat pump system we have still used the ‘official’ energy reading provided …

Photovoltaic Generator and Heat Pump: Daily Power Generation and Consumption (2016-06-01 12:21:02)
You can generate electrical power at home but you cannot manufacture your own natural gas, oil, or wood. (I exempt the minority of people owning forestry). This is often an argument for the combination of heat pump and photovoltaic generator. …

Everything as a Service (2016-05-19 13:57:08)
Three years ago I found a research paper that proposed a combination of distributed computing and heating as a service: A cloud provider company like Google or Amazon would install computers in users’ homes – as black-boxes providing heat to …

Alien Energy (2016-04-15 17:03:12)
I am sure it protects us not only from lightning but also from alien attacks and EMP guns … So I wrote about our lightning protection, installed together with our photovoltaic generator. Now our PV generator is operational for 11 …

No, You Cannot ‘Power Your Home’ by One Hour of Cycling Daily (2016-02-07 15:45:30)
In the past days different versions of an article had popped up in my social media streams again and again – claiming that you could power your home for 24 hours by cycling for one hour. Regular readers know that …

Temperature Waves and Geothermal Energy (2016-01-22 11:04:48)
Nearly all of renewable energy exploited today is, in a sense, solar energy. Photovoltaic cells convert solar radiation into electricity, solar thermal collectors heat hot water. Plants need solar power for photosynthesis, for ‘creating biomass’. The motion of water and …

How Does It Work? (The Heat Pump System, That Is) (2016-01-07 11:13:05)
Over the holidays I stayed away from social media, read quantum physics textbooks instead, and The Chief Engineer and I mulled over the fundamental questions of life, the universe and everything. Such as: How to explain our heat pump system? …

Half a Year of Solar Power and Smart Metering (2015-12-07 11:11:53)
Our PV generator and new metering setup is now operational for half a year; this is my next wall of figures. For the first time I am combining data from all our loggers (PV inverter, smart meter for consumption, and …

Peter von Rittinger’s Steam Pump (AKA: The First Heat Pump) (2015-11-24 09:51:42)
Peter von Rittinger’s biography reads like a success story created by a Victorian novelist, and his invention was a text-book example of innovation triggered by scarcity ( Bio DE / EN). Born 1811, he was poor and became an orphan …

The Impact of Ambient Temperature on the Output Power of Solar Panels (2015-11-13 09:21:38)
I have noticed the impact of traversing clouds on solar power output: Immediately after a cloud has passed, power surges to a record value. This can be attributed to the focusing effect of the surrounding clouds and/or cooling of the …

Economics of the Solar Air Collector (2015-10-14 11:43:21)
In the previous post I gave an overview of our recently compiled data for the heat pump system. The figure below, showing the seasonal performance factor and daily energy balances, gave rise to an interesting question: In February the solar …

Heat Pump System Data: Three Seasons 2012 – 2015 (2015-09-29 17:23:33)
We have updated the documentation of monthly and seasonal measurement data – now including also the full season September 2014 to August 2015. The overall Seasonal Performance Factor was 4,4 – despite the slightly lower numbers in February and March, …

Having Survived the Hottest July Ever (Thanks, Natural Cooling!) (2015-08-11 09:27:07)
July 2015 was the hottest July ever since meteorological data had been recorded in Austria (since 248 years). We had more than 38°C ambient air temperature at some days; so finally a chance to stress-test our heat pump system’s cooling …

Solar Energy, Batteries, and Autonomy (2015-07-15 14:00:27)
This is the third post in my series on our photovoltaic generator. It had been a part of previous post with the data for the first month, but I cut and saved it as the other post was so long …

Solar Power: Some Data for the First Month. (2015-06-17 12:04:07)
On May 4, 2015, we started up our photovoltaic generator. Here are some numbers and plots for the first month – and what I plan to do next. Our generator has a rated power of 4,77 kWp (kilowatt peak), one …

An Efficiency Greater Than 1? (2015-06-01 08:41:32)
No, my next project is not building a Perpetuum Mobile. Sometimes I mull upon definitions of performance indicators. It seems straight-forward that the efficiency of a wood log or oil burner is smaller than 1 – if combustion is not …

Two Weeks After Lift-Off (2015-05-18 10:27:44)
After a little delay our photovoltaic generator went online – we had been waiting for the delivery of this sophisticated addition to our office decoration: People on G+ had very cool suggestions, such as a rotating alien-fighting device throwing darts. …

How to Evaluate a Heat Pump’s Performance? (2015-04-21 14:00:52)
The straight-forward way is to read off two energy values at the end of a period – day, month, or season: The electrical energy used by the heat pump and the heating energy delivered. The Seasonal Performance Factor (SPF) is …

Ice Storage Challenge: High Score! (2015-04-01 09:31:38)
Released from ice are brook and river By the quickening glance of the gracious Spring; The colors of hope to the valley cling, And weak old Winter himself must shiver, Withdrawn to the mountains, a crownless king. These are the …

We Have Come a Long Way: Rooftop Solar Power Now! (2015-03-23 23:12:13)
We had considered it already a few years ago – when we decided to live and work in the middle of a dusty and noisy construction site for a few months: The upper part of the roof is inclined by …

Data Logging with UVR1611 – FAQ (2015-03-18 15:10:40)
I have received several questions related to my article on data logging on this blog, or to my postings on monitoring and control on our German blog. Thus I have decided to write the article I would have wanted to read …

The Ice Storage Challenge (2015-03-08 12:41:11)
The more we enjoyed our spring-like winter, the more we were worried if we will ever see much ice in our underground water tank this heating season. So we did what I had announced – we switched off the solar …

“An Unprecedented Test for Europe’s Electricity System” (2015-02-27 15:56:31)
And we will not be able to contribute – by a hair. We have just ordered our photovoltaic generator, and installation is planned for April. It is the (partial) Solar Eclipse on March 20 that made Europe’s Transmission System Operators …

A Sublime Transition (2015-02-14 13:51:01)
Don’t expect anything philosophical or career-change-related. I am talking about water and its phase transition to ice because … …the fact that a process so common and important as water freezing is not fully resolved and understood, is astonishing. (Source) …

More Ice? Exploring Spacetime of Climate and Weather. (2015-01-28 14:58:07)
I have become obsessed with comparing climate data for different regions in the world and in different years (space + time). Finally I have found the tool I was looking for; now I can compare average Ice Days quickly – days …

Personal Risk Assessment (2015-01-22 12:47:53)
We all do risk management intuitively – when we decide on uploading our data to the cloud where the NSA may spy on us. Or when we install heating systems that depend on electrical energy. The previous post triggered an …

We Want Ice! (2015-01-15 17:14:50)
We haven’t seen much of it this winter yet. I am talking both about the ice you would expect in winter and about the one created from extracting heat from a water tank – our heat pump system‘s heat source. …

Cistern-Based Heat Pump – Research Done in 1993 (2014-12-14 21:54:52)
One of the most recent search terms on this blog was: ‘cistern for water source heat pump’. I wanted to double-check and searched for this phrase myself. This was the first Google Search result: Cistern-Based Water-Source Heat Pump System Design …

“Being Creative with What Is Available” (2014-11-27 11:11:00)
This is a quote from Simon Dale’s website who has built several eco-friendly ‘Hobbit’ houses. It reminded me of the cave house built into lava bubbles by Lanzarote’s most famous artist César Manrique: Being creative with what is available has …

Google and Heating Systems (2) (2014-11-15 16:24:46)
I googled our company name. Then I found this: Auftrag means order and the obfuscated parts contain our full company name, the Chief Engineer’s name, the URL of a vendor we ordered material from recently, invoice total, and a comment …

A 1970s Pioneer in Self-Sufficient Living (2014-11-08 12:53:56)
Living in southern France, Jean Pain developed a self-sustaining ecosystem in the 1970s that supplied his home with 100% of the energy needed. He built a 50 tons compost mound from chipped wood – brushwood that had to be cleaned out to lower the …

Pumped Heat from the Tunnel (2014-10-04 14:04:17)
The idea to use a reservoir of water as a heat pump’s heat source is not new. But now and then somebody dares to do it again in a more spectacular way. Provided governmental agencies give you permit, lakes or …

Biology / Chemistry Challenge or: Should We Really Blame the Dead Frog? (2014-09-28 10:28:28)
We often say we operate in Leonardo da Vinci Renaissance Mode – given our odd ‘portfolio of diverse services’. But as much as the Chief Engineer does not like to work with mortar, cement, or any other slimy substances I …

Big Data, Big Plastic Worms, and How to Utilize Your Cellar (2014-09-07 15:03:41)
Our heat pump system will soon commence its third heating season. The amount of measurement data collected so far has exceeded the capabilities of the software I had once developed; so I crafted a new application based on a real database server. Now you …

What Learning about Feynman’s Path Integrals Was Good for (2014-07-03 14:08:07)
I have gone to great lengths on this blog in order to explain how and why a degree in physics prepares you for seemingly different careers, or at least does not hurt. But it would have been so simple. I …

Art from Plastic and Wood (2014-05-31 09:52:18)
After the musings on Life, the Universe and Everything you deserve a break – and a post with not too much verbiage. I am borrowing some images from a series of posts the Chief Engineer is currently running on our …

Measurement Data for Our Heat Pump System – Finally Translated Documentation (2014-04-13 17:12:04)
In an earlier post  I said Although we have very innovative, and if I may say so, geeky / nerdy customers it is rather unlikely that we will plan heat pump systems in Australia via sending checklists or doing ‘remote …

Lost in Translation – an Overdue Update (2014-02-20 14:01:48)
In this post I try something new: I will keep it short. This is actually an update long overdue. Months ago I have written a post on how to control the four elements that is how to harvest energy from …

Greatest Innovation Ever (2013-09-04 15:01:28)
I like Top Something Lists, in particular the hilarious variety. In a more serious state of mind I wondered what a list of the top inventions or top innovations of humankind might comprise. (Nitpickers, I don’t care about distinguishing ‘innovation’ …

Welcome to the Real World! (2013-08-14 19:01:28)
Warning: This is a disturbing post – despite the allusion to The Matrix in the title it is – really – about the real world only. Hardly any geekiness included. In order to compensate for that I will craft a …

Controlling the Four Elements. Or: Why Heat Pumps Are Cool. (2013-02-26 21:41:24)
Despite my attempts to post mainly geeky and weird stuff peppered with (very often not down-to-earth) physics, I got involved in some serious discussions on renewable energy, sustainability, heat pumps, and the pleasures of Building Your Own Stuff. So I …

Trading in IT Security for Heat Pumps? Seriously? (2013-01-22 18:45:21)
Astute analysts of science, technology and the world at large noticed that my resume reads like a character from The Big Bang Theory. After all, an important tag used with this blog is cliché, and I am dead serious about theory and …

The First Heat Pump Ever Was Built in Austria (2012-12-10 17:46:49)
I have confessed recently that I am from Austria. So the patriot in me wants to entertain her readers with the story of a milestone in the history of engineering thermodynamics – set by an Austrian! The development of the …

Why Do Heat Pumps Pump Energy so Easily? (2012-05-10 14:22:28)
I know my posts are usually walls of text, but I am trying to improve! In his landmark physics course, the Feynman Lectures on Physics, Richard Feynman tries to explain what an explanation in physics actually is. You can always understand …

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