The Orphaned Internet Domain Risk

I have clicked on company websites of social media acquaintances, and something is not right: Slight errors in formatting, encoding errors for special German characters.

Then I notice that some of the pages contain links to other websites that advertize products in a spammy way. However, the links to the spammy sites are embedded in this alleged company websites in a subtle way: Using the (nearly) correct layout, or  embedding the link in a ‘news article’ that also contains legit product information – content really related to the internet domain I am visiting.

Looking up whois information tells me that these internet domain are not owned by my friends anymore – consistent with what they actually say on the social media profiles. So how come that they ‘have given’ their former domains to spammers? They did not, and they didn’t need to: Spammers simply need to watch out for expired domains, seize them when they are available – and then reconstruct the former legit content from public archives, and interleave it with their spammy messages.

The former content of legitimate sites is often available on the web archive. Here is the timeline of one of the sites I checked:

Clicking on the details shows:

  • Last display of legit content in 2008.
  • In 2012 and 2013 a generic message from the hosting provider was displayed: This site has been registered by one of our clients
  • After that we see mainly 403 Forbidden errors – so the spammers don’t want their site to be archived – but at one time a screen capture of the spammy site had been taken.

The new site shows the name of the former owner at the bottom but an unobtrusive link had been added, indicating the new owner – a US-based marketing and SEO consultancy.

So my take away is: If you ever feel like decluttering your websites and free yourself of your useless digital possessions – and possibly also social media accounts, think twice: As soon as your domain or name is available, somebody might take it, and re-use and exploit your former content and possibly your former reputation for promoting their spammy stuff in a shady way.

This happened a while ago, but I know now it can get much worse: Why only distribute marketing spam if you can distribute malware through channels still considered trusted? In this blog post Malwarebytes raises the question if such practices are illegal or not – it seems that question is not straight-forward to answer.

Visitors do not even have to visit the abandoned domain explicitly to get hacked by malware served. I have seen some reports of abandoned embedded plug-ins turned into malicious zombies. Silly example: If you embed your latest tweets, Twitter goes out-of-business, and its domains are seized by spammers – you Follow Me icon might help to spread malware.

If a legit site runs third-party code, they need to trust the authors of this code. For example, Equifax’ website recently served spyware:

… the problem stemmed from a “third-party vendor that Equifax uses to collect website performance data,” and that “the vendor’s code running on an Equifax Web site was serving malicious content.”

So if you run any plug-ins, embedded widgets or the like – better check out regularly if the originating domain is still run by the expected owner – monitor your vendors often; and don’t run code you do not absolutely need in the first place. Don’t use embedded active badges if a simple link to your profile would do.

Do a painful boring inventory and assessment often – then you will notice how much work it is to manage these ‘partners’ and rather stay away from signing up and registering for too much services.

Data for the Heat Pump System: Heating Season 2016-2017

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 ‘international audience’ I add a summary here plus some ‘cultural’ context:

Building: The house is a renovated, nearly 100-year old building in Eastern Austria: a typical so-called ‘Streckhof’ – an elongated, former small farmhouse. Some details are mentioned here. Heating energy for space heating of two storeys (185m2) and hot water is about 17.000-20.000kWh per year. The roof / attic had been rebuilt in 2008, and the facade was thermally insulated. However, the major part of the house is without an underground level, so most energy is lost via ground. Heating only the ground floor (75m2) with the heat pump reduces heating energy only by 1/3.

Climate: This is the sunniest region of Austria – the lowlands of the Pannonian Plain bordering Hungary. We have Pannonian ‘continental’ climate with low precipitation. Normally, monthly average temperatures in winter are only slightly below 0°C in January, and weeks of ‘ice days’ in a row are very rare.

Heat energy distribution and storage (in the house): The renovated first floor has floor loops while at the ground floor mainly radiators are used. Wall heating has been installed in one room so far. A buffer tank is used for the heating water as this is a simple ‘on-off’ heat pump always operating at about its rated power. Domestic hot water is heated indirectly using a hygienic storage tank.

Heating system. An off-the-shelf, simple brine-water heat pump uses a combination of an unglazed solar-air collector and an underwater water tank as a heat source. Energy is mainly harvested from rather cold air via convection.

Addressing often asked questions: Off-the-shelf =  Same type of heat pump as used with geothermal systems. Simple: Not-smart, not trying to be the universal energy management system, as the smartness in our own control unit and logic for managing the heat source(s). Brine: A mixture of glycol and water (similar to the fluid used with flat solar thermal collectors) = antifreeze as the temperature of brine is below 0°C in winter. The tank is not a seasonal energy storage but a buffer for days or weeks. In this post hydraulics is described in detail, and typical operating conditions throughout a year. Both tank and collector are needed: The tank provides a buffer of latent energy during ‘ice periods’ and it allows to harvest more energy from air, but the collector actually provides for about 75% of the total ambient energy the heat pump needs in a season.

Tank and collector are rather generously sized in relation to the heating demands: about 25m3 volume of water (total volume +10% freezing reserve) and 24m2 collector area.

The overall history of data documented in the PDF also reflects ongoing changes and some experiments, like heating the first floor with a wood stove, toggling the effective area of the collector used between 50% and 100%, or switching off the collector to simulate a harsher winter.

Data for the past season

Finally we could create a giant ice cube naturally. 14m3 of ice had been created in the coldest January since 30 years. The monthly average temperature was -3,6°C, 3 degrees below the long-term average.

(Re the oscillations of the ice volume are see here and here.)

We heated only the ground floor in this season and needed 16.600 kWh (incl. hot water) – about the same heating energy as in the previous season. On the other hand, we also used only half of the collector – 12m2. The heating water inlet temperatures for radiators was even 37°C in January.

For the first time the monthly performance factor was well below 4. The performance factor is the ratio of output heating energy and input electrical energy for heat pump and brine pump. In middle Europe we measure both energies in kWh 😉 The overall seasonal performance factor was 4,3.

The monthly performance factor is a bit lower again in summer, when only hot water is heated (and thus the heat pump’s COP is lower because of the higher target temperature).

Per day we needed about 100kWh of heating energy in January, while the collector could not harvest that much:

In contrast to the season of the Ice Storage Challenge, also the month before the ‘challenge’ (Dec. 2016) was not too collector-friendly. But when the ice melted again, we saw the usual large energy harvests. Overall, the collector could contribute not the full ‘typical’ 75% of ambient energy this season.

(Definitions, sign conventions explained here.)

But there was one positive record, too. In a hot summer of 2017 we consumed the highest cooling energy so far – about 600kWh. The floor loops are used for passive cooling; the heating buffer tank is used to transfer heat from the floor loops to the cold underground tank. In ‘colder’ summer nights the collector is in turn used to cool the tank, and every time hot tap water is heated up the tank is cooled, too.

Of course the available cooling power is just a small fraction of what an AC system for the theoretical cooling load would provide for. However, this moderate cooling is just what – for me – makes the difference between unbearable and OK on really hot days with more than 35°C peak ambient temperature.

Computers, Science, and History Thereof

I am reading three online resources in parallel – on the history and the basics of computing, computer science, software engineering, and the related culture and ‘philosophy’. An accidental combination I find most enjoyable.

Joel on Software: Joel Spolsky’s blog – a collection of classic essays. What every developer needs to know about Unicode. New terms like Astronaut Architects and Leaky Abstractions. How to start a self-funded software company, how to figure out the price of software, how to write functional specifications. Bringing back memories of my first encounters with Microsoft VBA. He has the best examples – Martian Headsets to explain web standards.

The blog started in 1999 – rather shortly after I had entered the IT industry. So it is an interesting time capsule, capturing technologies and trends I was sort of part of – including the relationship with one large well-known software company.

Somewhere deep in Joel’s blog I found references to another classic; it was in an advice on how to show passion as an applicant for a software developer job. Tell them how reading this moved you to tears:

Structure and Interpretation of Computer Programs. I think I have found the equivalent to Feynman’s Physics Lectures in computer science! I have hardly ever read a textbook or attended a class that was both so philosophically insightful and useful in a hands-on, practical way. Using Scheme (Lisp) as an example, important concepts are introduced step-by-step, via examples, viewed from different perspectives.

It was amazing how far you can get with purely Functional Programming. I did not even notice that they had not used a single assignment (Data Mutation) until far into the course.

The quality of the resources made available for free is incredible – which holds for all the content I am praising in this post: Full textbook, video lectures with transcripts, slides with detailed comments. It is also good to know and reassuring that despite the allegedly fast paced changes of technology, basic concepts have not changed that much since decades.

But if you are already indulging in nostalgic thoughts why not catch up on the full history of computing?

Creatures of Thought. A sublime book-like blog on the history of computing – starting from with the history of telephone networks and telegraphs, covering computing machines – electro-mechanical or electronic, related and maybe unappreciated hardware components like the relay, and including biographic vignettes of the heroes involved.

The author’s PhD thesis (available for download on the About page) covers the ‘information utility’ vision that was ultimately superseded by the personal computer. This is an interesting time capsule for me as well, as this story ends about where my personal journey started – touching personal PCs in the late 1980s, but having been taught the basics of programming via sending my batch jobs to an ancient mainframe.

From such diligently done history of engineering I can only learn not to rush to any conclusions. There are no simple causes and effects, or unambiguous stories about who invented what and who was first. It’s all subtle evolution and meandering narratives, randomness and serendipity. Quoting from the post that indicates the beginning of the journey, on the origins of the electric telegraph:

Our physics textbooks have packaged up the messy past into a tidy collection of concepts and equations, eliding centuries of development and conflict between competing schools of thought. Ohm never wrote the formula V = IR, nor did Maxwell create Maxwell’s equations.

Though I will not attempt to explore all the twists and turns of the intellectual history of electricity, I will do my best to present ideas as they existed at the time, not as we retrospectively fit them into our modern categories.

~

Phone, 1970s, Austria

The kind of phone I used at the time when the video lectures for Structure and Interpretation of Computer Programs had been recorded and when I submitted my batch jobs of Fortran code to be compiled. I have revived the phone now and then.

 

Tinkering, Science, and (Not) Sharing It

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 at 120 degree angles from the others (this is called a “true wye”) and we take elbows of the appropriate angle, we can make the edges come together below the center at exactly the correct angles.

A pivotal moment: What you consider tinkering is actually research-paper-worthy science. Here are some images from the Chief Engineer’s workbench.

The supporting construction of our heat exchangers are built from standard parts connected at various angles:

The final result can be a cuboid for holding meandering tubes:

… or cascaded prisms with n-gon basis – for holding spirals of flexible tubes:

The implementation of this design is documented here (a German post whose charm would be lost in translation unless I wanted to create Internet Poetry).

But I also started up my time machine – in order to find traces of my polyhedra research in the early 1980s. From photos and drawings of the three-dimensional crystals in mineralogy books I figured out how to draw two-dimensional maps of maximally connected surface areas. I cut out the map, and glued together the remaining free edges. Today I would be made redundant by Origami AI.

I filled several shelves with polyhedra of increasing number of faces, starting with a tetrahedron and culminating with this rhombicosidodecahedron. If I recall correctly, I cheated a bit with this one and created some of the pyramids as completely separate items.

I think this was a rather standard hobby for the typical nerdy child, among things like growing crystals from solutions of toxic chemicals, building a makeshift rotatable telescope tripod from scraps, or verifying the laws of optics using prisms and lenses from ancient dismantled devices.

The actually interesting thing is that this photo is the only trace of any of these hobbies. In many years after creating this stuff – and destroying it again – I never thought about documenting it. Until today. It seems we weren’t into sharing these days.

Simulations: Levels of Consciousness

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 yearly average temperatures or energies? The latter are provided by tools used by governmental agencies or standardization bodies – allowing for a comparison of different systems.

In a true simulation the time intervals so small that you catch all ‘relevant’ changes of a system. If a heating system is turned on for one hour, then turned off again, he time slot needs to be smaller than one hour. I argued before that calculating meaningful monthly numbers requires to incorporate data that had been obtained before by measurements – or by true simulations.

For our system, the heat flow between ground and the water/ice tank is important. In our simplified sizing tool – which is not a simulation – I use average numbers. I validated them by comparing with measurements: The contribution of ground can be determined indirectly; by tallying all the other energies involved. In the detailed simulation I calculate the temperature in ground as a function of time and of distance from the tank, by solving the Heat Equation numerically. Energy flow is then proportional to the temperature gradient at the walls of the tank. You need to make assumptions about the thermal properties of ground, and a simplified geometry of the tank is considered.

Engineering / applied physics in my opinion is about applying a good-enough-approach in order to solve one specific problem. It’s about knowing your numbers and their limits. It is tempting to get carried away by nerdy physics details, and focus on simulating what you know exactly – forgetting that there are huge error bars because of unknowns.

This is the hierarchy I keep in mind:

On the lowest level is the simulation physics, that is: about modelling how ‘nature’ and system’s components react – to changes in the previous time slot. Temperatures change because energies flows, and energy flows because of temperature differences. The heat pump’s output power depends on heating water temperature and brine temperature. Energy of the building is ‘lost’ to the environment via heat conduction; heat exchangers immersed in tanks deposit energy there or retrieve it. I found that getting the serial connection of heat exchangers right in the model was crucial, and it required a self-consistent calculation for three temperatures at the same point of time, rather than trying to ‘follow round the brine’. I used the information on average brine temperatures obtained by these method to run a simplified version of the simulation using daily averages only – for estimating the maximum volume of ice for two decades.

So this means you need to model your exact hydraulic setup, or at least you need to know which features of your setup are critical and worthy to model in detail. But the same also holds for the second level, the simulation of control logic. I try to mirror production control logic as far as possible: This code determines how pumps and valves will react, depending on the system’s prior status before. Both in real life and in the simulation threshold values and ‘hystereses’ are critical: You start to heat if some temperature falls below X, but you only stop heating if it has risen above X plus some Delta. Typical brine-water heat pumps always provide approximately the same output power, so you control operations time and buffer heating energy. If Delta for heating the hot water buffer tank is too large, the heat pump’s performance will suffer. The Coefficient of Performance of the heat pump decreases with increasing heating water temperature. Changing an innocuous parameter will change results a lot, and the ‘control model’ should be given the same vigilance as the ‘physics model’.

Control units can be tweaked at different levels: ‘Experts’ can change the logic, but end users can change non-critical parameters, such as set point temperatures.We don’t restrict expert access in systems we provide the control unit for. But it make sense to require extra input for the expert level though – to prevent accidental changes.

And here we enter level 3 – users’ behavior. We humans are bad at trying to outsmart the controller.

[Life-form in my home] always sets the controller to ‘Sun’. [little sun icon indicating manually set parameters]. Can’t you program something so that nothing actually changes when you pick ‘Sun’?

With heat pumps utilizing ground or water sources – ‘built’ storage repositories with limited capacity – unexpected and irregular system changes are critical: You have to size your source in advance. You cannot simply order one more lorry load of wood pellets or oil if you ‘run out of fuel’. If the source of ambient energy is depleted, the heat pump finally will refuse to work below a certain source temperature. The heat pump’s rated power has match the heating demands and the size of the source exactly. It also must not be oversized in order to avoid turning on and off the compressor too often.

Thus you need good estimates for peak heat load and yearly energy needs, and models should include extreme weather (‘physics’) but also erratic users’ behaviour. The more modern the building, the more important spikes in hot tap water usage get in relation to space heating. A vendor of wood pellet stoves told me that delivering peak energy for hot water – used in private bathrooms that match spas – is a greater challenge today than delivering space heating energy. Energy certificates of modern buildings take into account huge estimated solar and internal energy gains – calculated according to standards. But the true heating power needed on a certain day will depend on the strategy or automation home owners use when managing their shades.

Typical gas boilers are oversized (in terms of kW rated power) by a factor of 2 or more in Germany, but with heat pumps you need to be more careful. However, this also means that heat pump systems cannot and should not be planned for rare peak demands, such as: 10 overnight guests want to shower in the morning one after the other, on an extremely cold day, or for heating up the building quickly after temperature had been decreased during a leave of absence.

The nerdy answer is that a smart home would know when your vacation ends and start heating up well in advance. Not sure what to do about the showering guests as in this case ‘missing’ power cannot be compensated by more time. Perhaps a gamified approach will work: An app will do something funny / provide incentives and notifications so that people wait for the water to heat up again. But what about planning for renting a part of the house out someday? Maybe a very good AI will predict what your grandchildren are likely to do, based on automated genetics monitoring.

The challenge of simulating human behaviour is ultimately governed by constraints on resources – such as the size of the heat source: Future heating demands and energy usage is unknown but the heat source has to be sized today. If the system is ‘open’ and connected to a ‘grid’ in a convenient way problems seem to go away: You order whatever you need, including energy, any time. The opposite is planning for true self-sufficiency: I once developed a simulation for an off-grid system using photovoltaic generators and wind power – for a mountain shelter. They had to meet tough regulations and hygienic standards like any other restaurant, e.g.: to use ‘industry-grade’ dishwashers needing 10kW of power. In order to provide that by solar power (plus battery) you needed to make an estimate on the number of guests likely to visit … and thus on how many people would go hiking on a specific day … and thus maybe on the weather forecast. I tried to factor in the ‘visiting probability’ based on the current weather.

I think many of these problem can be ‘resolved’ by recognizing that they are first world problems. It takes tremendous efforts – in terms of energy use or systems’ complexity – to obtain 100% availability and to cover all exceptional use cases. You would need the design heat load only for a few days every decade. On most winter days a properly sized heat pump is operating for only 12 hours. The simple, low tech solution would be to accept the very very rare intermittent 18,5°C room temperature mitigated by proper clothing. Accepting a 20-minute delay of your shower solves the hot water issue. An economical analysis can reveal the (most likely very small) trade-off of providing exceptional peak energy by a ‘backup’ electrical heating element – or by using that wood stove that you installed ‘as a backup’ but mostly for ornamental reasons because it is dreadful to fetch the wood logs when it is really cold.

But our ‘modern’ expectations and convenience needs are also reflected in regulations. Contractors are afraid of being sued by malicious clients who (quote) sit next their heat pump and count its operating cycles – to compare the numbers with the ones to be ‘guaranteed. In a weather-challenged region at more than 2.000 meters altitude people need to steam clean dishes and use stainless steel instead of wood – where wooden plates have been used for centuries. I believe that regulators are as prone as anybody else to fall into the nerdy trap described above: You monitor, measure, calculate, and regulate the things in detail that you can measure and because you can measure them – not because these things were top priorities or had the most profound impact.

Still harvesting energy from air - during a record-breaking cold January 2017

Bing Says We Are Weird. I Prove It. Using Search Term Poetry.

Bing has done so repeatedly:

Bing Places asks for this every few months.

In order to learn more about this fundamental confusion I investigated my Bing search terms. [This blog has now entered the phase of traditionally light summer entertainment.]

Rules:

  • Raw material: Search terms shown in Bing Web Master Tools for any of my / our websites.
  • Each line is a search term of a snippet of a search term – snippets must not be edited but truncation of phrases at the beginning or end is allowed.
  • Images: Random pick from the media library of elkement.blog or our German blog (‘Professional Tinkerers – Restless Settlers‘)

_______________________

you never know
my life and my work

is life just about working
please try to give a substantial answer

A substantial answer.

element not found
map random elkement

Random elkement, confused by maps.

so as many of you may know (though few of you may care)
my dedication to science

this can happen if
the internet is always a little bit broken

The internet is always a little broken

google translate repetetive glitch poetry

_______________________

So let’s hear what Google has to say!
Same rules, only for Google Search Console:

_______________________

so called art
solar energy poem

ploughing through
proof of carnot theorem
thermodynamics in a nutshell

Thermodynamics in a nutshell.

mr confused
why him?

Mr Confused

plastic cellar
sublime attic
in three sentences or fewer, explain the difference

Plastic tank - 'ice storage'

Sublime attic.

name the three common sources of heat for heat pumps
magic gyroscope
frozen herbs
mice in oven

Had contained frozen herbs. Isomorphic to folding of ice/water tank pond liner.

shapeshift vs kraken
tinkers construct slimey
you found that planet z should not have seasons

Slimey

the best we can hope for is that
tv is dangerous

what is the main function of the mulling phase?
you connect a packet sniffer to a switch

Connect a sniffer - to your heat pump

how to keep plastic water tank cool in summer
throwing boiling water into freezing air

Freezing air.

just elke
self employed physicist
the force is strong in me

The force is strong in me.

  _______________________

Heat Transport: What I Wrote So Far.

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 versus insights from the few things you can solve analytically, and applications to our heat pump system.

So I checked what I have already written – and I discovered a series which does not show up as such in various lists, tags, categories:

[2014-12-14] Cistern-Based Heat Pump – Research Done in 1993 in Iowa. Pioneering work, but the authors dismissed a solar collector for economic reasons. They used a steady-state estimate of the heat flow from ground to the tank, and did not test the setup in winter.

Cistern-Based Water-Source Heat Pump System Design, 1993[2015-01-28] More Ice? Exploring Spacetime of Climate and Weather. A simplified simulation based on historical weather data – only using daily averages. Focus: Estimate of the maximum volume of ice per season, demonstration of yearly variations. As explained later (2017) in more detail I had to use information from detailed simulations though – to calculate the energy harvested by the collector correctly in such a simple model.

Simple simulations of volume of ice[2015-04-01] Ice Storage Challenge: High Score! Our heat pump created an ice cube of about 15m3 because we had turned the collector off. About 10m3 of water remained unfrozen, most likely when / because the ice cube touched ground. Some qualitative discussions of heat transport phenomena involved and of relevant thermal parameters.

Ice formation during the 'ice storage challenge'[2016-01-07] How Does It Work? (The Heat Pump System, That Is) Our system, in a slide-show of operating statuses throughput a typical year. For each period typical temperatures are given and the ‘typical’ direction of heat flow.

System in September - typical operations conditions[2016-01-22] Temperature Waves and Geothermal Energy. ‘Geothermal’ energy used by heat pumps is mainly stored solar energy. A simple model: The temperature at the surface of the earth varies sinusoidally throughout the year – this the boundary condition for the heat equation. This differential equation links the temporal change of temperature to its spatial variation. I solve the equation, show some figures, and check how results compare to the thermal diffusivity of ground obtained from measurements.

Measured 'wave' and propagation time[2016-03-01] Rowboats, Laser Pulses, and Heat Energy (Boring Title: Dimensional Analysis). Re-visiting heat transport and heat diffusion length, this time only analyzing dimensional relationships. By looking at the heat equation (without the need to solve it) a characteristic length can be calculated: ‘How far does heat get in a certain time?’

Temperature waves in ground - attenuation length of about 10 meters[2017-02-05] Earth, Air, Water, and Ice. Data analysis of the heating season 2014/15 (when we turned off the solar/air collector to simulate a harsher winter) – and an attempt to show energy storages, heat exchangers, and heat flows in one schematic. From the net energy ‘in the tank’ the contribution of ground can be calculated.

Energy storage, heat exchangers, heat flow[2017-02-22] Ice Storage Hierarchy of Needs. Continued from the previous post – bird’s eye view: How much energy comes from which sources, and which input parameters are critical? I try to answer when and if simple energy accounting makes sense in comparison to detailed simulations.

Hierarchy of needs - ambient energy in ice months[2017-05-02] Simulating Peak Ice. I compare measurements of the level in the tank with simulations of the evolution of the volume of ice. Simulations (1-minute intervals) comprise a model of the control logic, the varying performance factor of the heat pump, heat transport in ground, energy balances for the hot and cold tanks, and the heat exchangers connected in series.

Simulations of brine and tank temperature and volume of ice, based on system state in 1-minute intervals.(Adding the following after having published this post. However, there is no guarantee I will update this post forever ;-))

[2017-08-17] Simulations: Levels of Consciousness. Bird’s Eye View: How does simulating heat transport fit into my big picture of simulating the heat pump system or buildings or heating systems in general? I consider it part of the ‘physics’ layer of a hierarchy of levels.

Simulation - levels of consciousnessPlanned episodes? Later this year (2017) or next year I might write about the error made when considering simplified geometry – like modeling a linear 1D flow when the actualy symmetry is e.g. spherical.