Last year I wrote about A switching amplifier electronic design which can drive large power loads with high efficiency and tolerable distortion. The operational principle for this is that a pre-stage converts the input signal into a series of pulses which rapidly switch the end-stage on and off - that is a power-efficient mode of … Continue reading A better switching amplifier
Author: george georgovassilis
A comprehensive security enterprise architecture
I obtained permission to publish my presentation for an internal gig of a security enterprise architecture. When setting up a security architecture in the enterprise context topics like business continuity, people and processes, governance, services and technology are relevant. https://www.slideshare.net/GeorgeGeorgovassilis/security-architecture-127061728
docker-proxy port in use
Quick one: you're starting a container through docker-compose and it says a port is in use. You "netstat -plutn" it and find out, that port is in use by docker-proxy. Github user rdavaillaud knows what's going on: stop dockerremove all internal docker network: rm /var/lib/docker/network/files/start docker
Technical Debt
dilbert.com Technical debt is the amount of work needed to decrease the total cost of a product.Me The classical definition doesn't work Technical debt (TD) is intuitively easy to grasp as an inherent quality/complexity issue that makes a product hard to operate and change, which is a good description but not a good definition of … Continue reading Technical Debt
parchive: protecting backups against data corruption
As time goes by, my [place appropriate interval] backups may not grow much, but the size of my entire data archive exceeds the largest available hard disks (don't ask). Taking into account correctness guarantees by hard disk manufacturers, transmission errors over the network and who knows what else, I don't feel confident that I'll flip … Continue reading parchive: protecting backups against data corruption
Book of dark arts: selective disclosure with CSS
Show and hide pages and page elements with declarative CSS instead of imperative code
Book of dark arts: storing data in the view
Pentagram, source Wikipedia. Towards the end of the year I'll indulge in the dark arts, join the goblins and leave my white architect hat under the Christmas tree where it belongs. I'm helping a friend (a technically minded, non-programmer) write his first mobile app . We wanted to keep everything simple: use technologies which can … Continue reading Book of dark arts: storing data in the view
Ubuntu on the ASUS VivoBook 17
Following the proud tradition [1],[2],[3] of documenting Linux installations on all the hardware I break, I'm happy to report that Ubuntu 18.04 works fine on the ASUS VivoBook 17 (model number X705U). Things I tested and that work: OS boots from USB and from harddisk Secure boot WLAN USB On board and external (USB) camera … Continue reading Ubuntu on the ASUS VivoBook 17
Thunderbird forgetting passwords
After a simultaneous Thunderbird upgrade and profile migration from Windows to Linux the mail program permanently forgets passwords. The setting: Thunderbird 52 on Windows Back up profile Restore profile to Thunderbird 60 on Linux Observe that all passwords to all accounts are lost even if entered again This seems to be some … Continue reading Thunderbird forgetting passwords
Software architecture for 5G networks
The 5G mobile network specification introduces network function virtualization [NFV] which enables mobile network operators (carriers henceforth) to expose network resources to business applications as PaaS solution building blocks [SBB]. Naturally, this moves 5G into the focus of software architecture. Unsurprisingly, the NFV specs detail services from the carrier's point of view, so they are … Continue reading Software architecture for 5G networks
