Zoom Panopto integration

Helmut Neukirchen, 9. November 2021

Panopto can tell Zoom to copy Zoom meeting cloud recordings to Panopto. You can configure this automatic import/export by clicking in the very upper right corner of https://rec.hi.is/ on your user name and then select "User Settings".

University of Iceland is running Panopto with at least two different storage spaces: the old storage space used when logged-in to Panopto via UGLA (for Panopto videos accessible via UGLA) and the new storage space when logged-in to Panopto via Canvas (for Panopto videos accessible via Canvas).

On https://rec.hi.is/, you can in the upper right corner log out and log in to change between these two spaces. But you cannot copy videos between these two spaces -- but UTS help desk can do so.

For the Zoom integration, the problem is that recordings may end up in the wrong space: whatever the last log-in to Panopto was, sets the integration, i.e. tells Zoom where to store the video for all future Zoom session recordings. So take care that your last log-in was into the intended storage space before a Zoom cloud recording starts. (Or ask UTS help desk to fix it afterwards.)

Ice tea vs. IoT: LoRa

Helmut Neukirchen, 20. October 2021

Ice tea or IoT -- what do you prefer?

When I ordered the TTGO T-BEAM, I liked that it combines LoRa and GPS and it even supports a 18650 battery (18650 cells with internal protection circuit are somewhat longer, but still fit -- although very tight) including a good charging chip to charge the Li-Ion cell -- not LiFePO -- via USB (USB can also be used to power the device without using the battery holder). The ublox NEO-6M GPS chip has a dedicated backup (super)capacitor (looks like a coin cell battery) to buffer the GPS chips' RTC and almanach, but probably only for a few minutes.

Just when the delivery arrived, I found video #182 from Andreas Spiess, reporting that older TTGO designs had some design flaws: the 868-915 MHz versions have passive RF components (coils and capacitors to tune the frequency) that are not specific enough for the 868 MHz that we use here in Europe (some even fixed that) and the LoRa antenna could be better (all the videos by Andreas Spiess can only be recommended, including the LoRa videos). I was then happy to see that in newer designs, including the T-TBEAM, the WiFi antenna is placed better and in fact, the T-TBEAM even has a connector for an external WiFi antenna (but would need some minor soldering); also the LoRa and GPS part is now shielded by a metal cage. I was relieved to find the more recent video #224 measuring the T-BEAM and other newer boards, judging the newer designs to be OK.

I already expected that a better GPS antenna might be needed (and the tiny original one is only fixed with some adhesive tape that does not hold very well).

In summary, the T-BEAM seems not to be that bad (even the passive component that are too generic for 868 MHz turn out to be OK), but many reports indicate that the power consumption is rather high (This whole thread is also a worthwhile reading). 10 mA seem to be the minimum possible even during deep sleep. Concerning the power consumption, there seems to be an issue with deep-sleep. There is also a video on what is possible with ESP32 and deep sleep.

Some people complained that they got only 900m instead of kilometers of range. The comments for video #224 mention that an older library had a flaw concerning the transmit power which did lead in that video to a low transmission power; according to the comments, this has at least been fixed now in the LoRa library by Sandeep Mistry that can be found in the Arduino Library Manager.

A display can also be connected, but to reduce power consumption, it might be better to make it removable by using a female header.

Andreas Spiess recommends in his videos WeMos D1 ESP8266 and a Hope RFM95W LoRa module for which even a PCB is available (recommending as well WeMos D1 as ESP2866 board) -- it however needs SMD soldering. Nexus by Ideetron has elsewhere been mentioned as low power solution, but has only a small user base and thus lacks information -- and GPS can anyway be expected to be the big power consumer.
Concerning the LoRaWAN libraries, MCCI seems to be the only one that it actively maintained and communication with The Things Network needs to save some state information (for joining via OTAA) which MCCI stores in RAM that is not buffered in deep-sleep of ESPs. So for using OTAA, MCUs that do buffer the RAM (i.e. newer ATMEL MCU like in newer Arduino) would be preferable, e.g. Atmega 1284p together with a watchdog for waking up periodically has extremely low power consumption (0.5 μA in deep sleep) but lacks GPS. Other low power designs provide even triple GNSS and acceleration-detection watchdog. In addition to the ublox GNSS chips, there are some approaches that claim to reach lower power consumption by off-loading GNSS solver processing via LoRa to some external clouds server infrastructure or doing extreme A-GPS data compression for LoRa transmission from a cloud.

The really cool thing is that even satellites serve as LoRa repeaters (if there is a clear line of sight, LoRa has a theoretical range of 1300 kilometers, thus even reaching low earth orbit satellites). By this, sensors that have no LoRa connection on the earth, can still reach a LoRa repeater in the sky and forward their messages. (But you probably need an amateur radio license for the used 70 cm frequency band: 435 MHz / 436 MHz up- and downlink.)

I also got two TTGO Lora32 v1.6.1 that have LoRa, a card reader, and a tiny display on the back, but not GPS. On one of them, the WiFi antenna was already loose when unpacking (see the 3D sheet metal in the photo below). Need to check how easy it is to solder it back again (or whether rather a hot air rework station is needed) or is it as opportunity to add an SMA/UFL connector? (There is also an UFL antenna connector, but since it as close to the LoRa SMA antenna connector, I guess the UFL connector is as well for LoRa -- after desoldering some 0 Ohm SMD resistor and creating a soldering bring/reusing that 0 Ohm SMD resistor.)
Even though TTGO Lora32 comes with a cable to connect a battery, TTGO Lora32 version v1.6 had a fire issue where the battery explodes. I checked the schematics: My v1.6.1 has this issue fixed and the TTGO T-BEAM uses anyway a different charging IC that is claimed to be pretty good.

Also, double check the pinout: some complain that the pinout provided by LilyGO can be wrong.

Depending on the applications, I might use LoRa for device-to-device commnication, or LoRaWAN via The ThingsNetwork that has a coverage in Reykjavík, but fair use limits, e.g. 10 messages to the device per day, which could be avoided by setting-up my private LoRaWAN using ChirpStack.

Talking about lora (a popular name for parrots as the Spanish word for parrot is loro): did I mentioned already that the Computer Science department has moved and already a new visitor...?

DIY DVB-T/DVB-T2 indoor sleeve antenna made out of a coax antenna cable

Helmut Neukirchen, 13. October 2021

As the DVB-T sender has been moved here within Reykjavík, I had to adjust my indoor antenna which is simply built by turning a coax-antenna cable into a half-wave dipole antenna (essentially, a variant of a sleeve antenna) : the outer insulation of the coax cable was removed so that the part with the inner wire has a lambda/4 length and the left-over shield was peeled and turned inside out over the insulation so that it also has lambda/4 length (in sum: lambda/2). The aluminum foil that was part of the shielding was removed and finally, the inner insulation removed so that the inner wire remains totally uncovered. Take care that remainders of the shield do not touch the inner wire.

For the details, including the calculations, see: http://www.vdr-wiki.de/wiki/index.php/DVB-T_Antennen (in German, but the calculations work in any language -- note that they use a correction factor of 0.95 for the length of the shield and 0.97 * lambda/4 for the length of the inner wire -- but, well, the antenna needs to cover some frequency range, so these corrections probably matter not that much).

More info on the senders in Iceland can be found at https://vodafone.is/sjonvarp/sjonvarpsthjonusta/thjonustusvaedi/ (see map at the bottom). The sender operated by Vodafone on Úlfarsfell broadcasts on three UHF channels with 8 MHz bandwidth:

  • Channel 26 (514 MHz center frequency): RÚV HD (DVB-T2), RÚV 2 HD, BBC Brit, DR1, Food Network, Hringbraut, N4, National Geographic, Rás 1, Rás 2, Rondo (the latter are not TV, but radio)
  • Channel 27 (522 MHz center frequency): RÚV (DVB-T only), Stöð 2, Stöð 2 Bíó, Stöð 2 Fjölskylda, Stöð 2 Sport, Stöð 2 Sport 2, Rás 1, Rás 2, Bylgjan, Fm957 , Léttbylgjan, Xið
  • Channel 28 (530 MHz center frequency): Stöð 2 Golf, Stöð 2 Sport 3, Stöð 2 Sport 4, Animal Planet, Discovery.

Using 522 MHz, lambda/4 is 14.36 cm which I used for the above DIY antenna.

With the older sender where I had an unblocked line of sight, the reception was yielding almost 100% signal strength and signal quality, but with the new location of the sender on Mt. Úlfarsfell, my reception got really bad (there is a hill and high buildings in the line of sight) and signal strength is even fluctuating, which might be explained by the weather, e.g. rain can be expected to weaken the signal strength.

In addition to the above programmes, my TV receives a far stronger DVB-T signal on on channel 41 (634 MHz -- which means the calculated lambda/4 does not fit perfectly, still the received signal strength is close to 100%) which must be another sender than the one from Vodafone (it anyway broadcasts missionary programmes only).

EOSC-Nordic Knowledge Hub

Helmut Neukirchen, 29. September 2021

The EOSC-Nordic project has a knowledge hub that contains knowledge on using the European Open Science Cloud, e.g. services for storing and finding research data or accessing cross-border scientific computing (in particular with a Nordic focus): https://www.eosc-nordic.eu/knowledge-hub/.

Eclipse, modular projects and JUnit

Helmut Neukirchen, 21. September 2021

I (and many others) always had problems making JUnit (as added by Eclipse automatically when creating JUnit test cases) work with modular projects, i.e. projects that use module-info.java files to define dependencies. Finally, I found solutions:

  • Let the new project wizard not create the module-info.java file -- deleting it afterwards might not be enough as Eclipse did already some modification the the module path settings (OK, trivial) or
  • Choose Java ≤8 in settings (i.e. module-info.java ignored -- again: trivial) or
  • Apply quick-fixes: in the class containing your JUnit test cases, hover over the org.junit.jupiter.api import and select the quick-fix: “Add ‘requires […]’ to module-info.java”. Then in module-info.java: hover with mouse over the squiggle line (the important point is: clicking on the light bulb does not give any quick-fix, so you need to hover) and do: “Move classpath entry ‘JUnit5’ to modulepath”. This should fix it! or
  • Create an Eclipse project with extra src folder (e.g. src-test or use the Maven default structure) that has (via “Allow output folders for source folders”) its own output folder (e.g. bin-test or use the Maven default structure) and that has “Contains test sources” toggled to “Yes” (in project properties - Java Build Path -Source). The test src folder should then have a more grey-ish icon. Either do this with the New project wizard, or afterwards using project properties. As a result, JUnit is then not part of the modular project anymore. (Has also the advantage that test code is better separated.)

Computer Science department has moved to Gróska building / HÍ námsbraut í tölvunarfræði flýtt í Grósku

Helmut Neukirchen, 23. August 2021

The Computer Science department has moved to the new Gróska building (between Askja building and the DeCode Genetics building -- probably, most people know it, because there is a gym on the ground floor and CCP is located there). The official visiting address is: Bjargargata 1, 102 Reykjavik. You can find us also on OpenStreetMap.

(I still need to find out which address needs to be used for paper mail to end up in the department's post inbox.)

The Computer Science department is on the 3rd floor -- the same floor where CCP is located, however, we are at the southern-most wing of the building -- see the purple lines in the photo below:

Computer Science location within Gróska

 

The floor plan of the Computer Science department is below. I should mark there where the meeting rooms are. For the time being, the two most popular meeting rooms: the big teaching room Ada is GR-321, Frances Elizabeth Allen is honored by room Frances in GR-310.

Floor plan of the Comuter Science department

I am located in room 306. The phone numbers are now routed via MS Teams that I am not going to install on my Linux system: rather call me on my provided mobile phone number.

We are still lacking furniture and for visitors, I had to build our own chairs out of cardbox, e.g.: https://www.wikihow.com/Build-a-Cardboard-Stool or https://www.hometalk.com/diy/decorate/rooms/diy-cardboard-stool-looks-like-wood-31556361?expand_all_questions=1

Update: we just got visitor chairs and some other visitor:

In addition to a bicycle storage room for employees, there are also EV chargers, however an RFID card from Bílahleðslan is needed: I have just ordered one...

PhD Defense Federated Access to Collaborative Compute and Data Infrastructures

Helmut Neukirchen, 29. June 2021

Shiraz Memon successfully defended his PhD thesis in Computer Science on Federated Access to Collaborative Compute and Data Infrastructures. The thesis covers how researchers can perform eScience by discovering services (such as accessing data and processing data) on remote research and e-infrastructures and authenticate (such as logging in order to use the service) and how authorization can be done (i.e. deciding which services are allowed to be used).

The thesis was streamed, Wed, 30. June 2021 starting from 09:30 (UTC), and the recording is available via: https://livestream.com/hi/doktorsvornshmedshirazmemon

PhD defense announcement

This PhD is an example of the collaboration between the Faculty of Industrial Engineering, Mechanical Engineering and Computer Science and Jülich Supercomputing Centre (JSC).

Members of the PhD commitee were Morris Riedel, Helmut Neukirchen, and Matthias Book, opponents were David Wallom and Shukor Abd Razak. The head of faculty, Rúnar Unnþórsson, was steering the defense.

Power consumption of Raspberry Pi 4 versus Intel J4105 system

Helmut Neukirchen, 7. June 2021

While I intended to use a Raspberry Pi 4 as a small server, I also ordered from China a small system (BEBEPC, comparable to the Qotom mini PCs. While Qotom mini PCs are slightly better documented, they typically have less powerful CPUs: even though they have Core i3 CPUs, these are so old that a more recent Celeron CPU is faster) based on a Intel J4105 CPU (= TDP of 10 W, 4 cores, 1.5 GHz base frequency, 2.5 GHz burst frequency) which has over the Raspi the advantage of native SATA ports (one standard SATA connector with 5 V power supply and one mSATA connector carrying 3.3 V power supply -- I am currently waiting for an mSATA to SATA adapter and a 5 V SATA power splitter cable to be able to have a RAID system of two SATA SSDs -- mSATA SSDs are only available in smaller sizes). However, the biggest advantage is that it is (obviously) able to run Intel-only code, e.g. in particular (Docker) containers only available for Intel.

Both systems have 8 GB LPDDR4 RAM. It might be interesting whether a SO-DIMM that has integrated ECC error-correction capabilities from https://www.intelligentmemory.com/ is available for the J4105 which would make it an even better small server.

Both systems can be passively cooled: for the Raspy, I used a cooling case from https://www.coolingcases.com/ -- it cools well, but the metal affects the range of the onboard Wifi (not that relevant for a server). The J4105 came as well with a case that allows passive cooling -- while it is still tiny for a PC, it has approx. 4 times the volume of the Raspi.

The J4105 system has for sure more compute power than the Raspi's ARM CPU, so the remaining question is the power consumption. Hence, I did some tests and measurements using a cheap power meter that claims to have a 2% precision. Both systems were connected via FullHD HDMI to a monitor.

Intel J4105 measurements

As I did not install Linux yet, it was running Windows 10 and idle refers to having only the built-in task manager running in foreground (to display clock frequency) and all the background services that Windows 10 has by default. CPU load was generated using a batch file containing an endless loop.

The J4105 clocks down to 0.78 GHz when idle and the power consumption of the whole system (with one mSATA and one SATA SSD) is then 3.8 W.

With 1 core being busy, it still clocks up to 2.4 GHz and consumes 7.2 W.

With 2 cores being busy, it still clocks up to 2.4 GHz and consumes 10.3 W.

With 3 cores being busy, it clocks up to 2.35 GHz and consumes between 11.8 W and 12.1 W.

With 4 cores being busy, it clocks up to 2.19 GHz and consumes between 11.4 W and 12.0 W. (So it seems the reduced clock saves power).

I did run it with 4 cores being busy for an hour, and the measurements did not change, e.g. no thermal throttling seems to have occurred (nor did the case get hot, so a really good passive cooling -- or the contact between CPU and case is bad, but then thermal throttling could have been expected).

Raspberry Pi 4 measurements

I had OSMC with KODI running, but nothing else, i.e. the KODI UI being idle, but all the background services running. The latest firmware as of 4. June 2021 was used, storage was SDHC card only. CPU load was generated using the stress command.

The Raspberry Pi 4 consumed idle 3.8 W to 4.0 W.

With 1 core being busy, it consumes 4.5 W.

With 2 cores being busy, it consumes 5.0 W.

With 3 cores being busy, it consumes between 5.4 W and 5.5 W.

With 4 cores being busy, it consumes 6.0 W.

Temperature with the cooling case from https://www.coolingcases.com/ was approx. 52° C (so it prevented thermal throttling that would start at 80° C). Surprisingly, even in idle mode, the temperature was 40-42° (the tiny case does feel much warmer than the bigger case of the Intel system -- so, it seems: size matters).

Conclusions

In summary, the idle power consumption of both systems is comparable and while the busy consumption is lower with Raspberry Pi 4, it is of course less powerful than the J4105 system. For the J4105, I never observed the full 2.5 GHz burst clock rate (but 2.4 GHz). Even though the CPU TDP is 10 W, the whole system consumed up to 12.1 W (e.g. the RAM, the two SSDs, WiFi, HDMI output, external power supply, etc. probably also to add their share -- during boot, I even saw 14.8 W).

Note that others suggest 2.7 W idle for the Raspi 4 (but seems to require switching off a lot of I/O, e.g., HDMI etc. -- which I did not do, nor did I minimise background processes) or even as low as 2.1 W. On the other hand, many other report that they neither (with either a fan or a heatsink) get the system cooler than 42° in idle, so getting the Raspy warmer than the touch of your hand seems to be normal, but the J4105 system with the bigger case was considerably cooler.

It seems that the J4105 is a good 24/7 home server system, i.e. more powerful than the Raspi when needed, but still not consuming more power when idle.

The ultimate passively cooled server with ECC ram would be ASRock Industrial iBOX-V2000M or iBOX-V2000V -- but these are not yet available and in particular not for private users.

Why you should study Software Engineering

Helmut Neukirchen, 7. June 2021

Studying Software Engineering is important because Software is the future and future is now. And someone needs to create all this software that is shaping our future.

Software Engineering is more than just programming, it rather looks at big picture , namely the whole life of the software: from the start where you need to talk to customers to find out what software they actually over to the actual programming, user interface and user experience, quality assurance and this is all guided by project management where you need to make people work together.

Software Engineering covers so many different aspects that students need to come from all kinds of different backgrounds:
female and male, those who are good at math, those who are good at communicating with other people, those who are picky about details, those who are creative. Essentially everyone!

When you start studying Software Engineering, you do not need to be able to program: you will learn that in our courses. But you need to be able to talk to other people and at the same time do not fear thinking like an engineer, such as doing math and applying systematic processes!

The nice thing about developing software is that only your imagination is the limit: you can create everything just by turning your mind into code and then it runs and you can see it immediately working. This is so rewarding!

Studying Software Engineering at the University of Iceland is very practical: you do not only learn the theory, but also apply it in the courses. For example, in our Bachelors program, there is a Software Engineering project that spans a whole 1 year.

Those who graduate from here, will find easily a job at a good salary and can work in fact in all kinds of different fields: be it banking, insurance, health, industry, administration, tourism, gaming, even arts:
simply everywhere, nowadays Software is needed!

Further information

If you want more information on our Software Engineering programmes:

Bachelor (B.Sc.)

Software Engineering (Hugbúnaðarverkfræði)

Master (M.Sc.)

Software Engineering (Hugbúnaðarverkfræði)

Ph.D.

And of course, you can also do a PhD in any of these programmes. Before you apply, contact a professor: either by a personal visit or -- if you are located abroad -- by writing an old school paper letter (professors get hundreds of email with PhD applications where it is obvious that the same email was written to many professors and thus, these email are considered as spam -- but a paper mail makes an impress)!

Horizon 2020 Future and Emerging Technologies programme: Dynamical Exascale Entry Platform - Extreme Scale Technologies (DEEP-EST) about to finish

Helmut Neukirchen, 26. April 2021

The Horizon 2020 Future and Emerging Technologies programme: Dynamical Exascale Entry Platform - Extreme Scale Technologies (DEEP-EST) project has finished its work and was praised for its results in the final review of the project's outcome.

We still have to harvest our results by writing publications on the results, but you can find a video already here:

All our travel emissions have been offset. As it is not clear whether funding regulations allow to offset emissions due to supercomputer energy consumption, these were not compensated. However, one of the research topics of the DEEP-EST project was energy efficiency and we achieved a lot by using specialised (=more efficient) accelerator hardware.