DavidHaerer

I appreciate HN for staying up-to-date with technical news.

For my side hustle I have to ramp-up on other areas like marketing, legal, sales, ...

So I wonder if there are similar high-quality sources like HN for these areas.

I'm considering switching from a selfhosted Nextcloud AIO to a managed cloud provider (e.g. MS OneDrive) so I don't have to care about backups, security, etc.. However I like the flexibility I get from self-hosting.

Can you recommend any cloud providers for the typical Linux user / web developer?

Recently I've switched from the UNIX pass password manager to Bitwarden and I'm very happy with it. So I'm looking for something similar among the cloud providers.

I'm trying to understand the memristor and have an idea for how to build a mechanical system, that might exhibit the characteristics of a memristor. However, ChatGPT keeps telling me it wouldn't work, but I'm not convinced. As you might already conclude, I only have a basic understanding of electrical engineering, so I hope this question is not too stupid.

I've started with this [1] common diagram showing the relations of the four fundamental quantities.

Charge q: Experiences positive / negative force in an electric field.

Current i: Amount of charge passing through a surface.

Voltage v: Potential energy of charge.

Flux Linkage Φ: Amount of magnetic field passing through a surface.

dq = i dt: Definition of current as charge per time.

dv = R di: Ohms law, voltage drops as current flows through a resistor.

dq = C dv: Charge on a capacitor changes with a voltage change according to the capacitance.

dΦ = L di: An inductor creates a magnetic field when current flows through it according to the inductance.

dΦ = v dt: Faradays law of induction, change of the magnetic flux linkage in an inductor induces a voltage change across the inductor.

dΦ = M dq: Formula of the memristor. The device must change resistance M according to the amount of charge that has passed through it.

According to ChatGPT, the dΦ in the memristor is an abstract state variable and does not imply there is a magnetic field involved. But lets get to the mechanical system.

Imagine a coil on one side, and a rotatable permanent magnet on the other side. When charge flows through the coil, it creates a magnetic field, causing the permanent magnet to rotate to align field lines. The changing magnetic field of the permanent magnet causes a voltage change in the coil. Hence the measured resistance of the coil changes, when current flows through it. The formula dΦ = M dq seems very intuitive to me, now that it involves an real magnetic field that changes.

What do you think of the described mechanical system. Can it behave like a memristor? According to my understanding, the way to find out would be to build it and make measurements of voltage and current. Plotting it on the v-i plane must show a pinched hysteresis loop.

Also, isn't this very similar to how magnetic storage works using the magnetoresistance effect?

[1]: https://en.wikipedia.org/wiki/Memristor?useskin=vector#/media/File:Two-terminal_non-linear_circuit_elements.svg

I'd like to know how you use gnome-keyring. From their Security Philosophy [1], Basics of Storing Secrets [2] and Security FAQ [3] wiki pages, I understand that the keyring helps against passive attacks (i.e. the attacker does not have access to an active user session). However, if the attack can execute code in the same user session where the keyring is unlocked, they have access to all secrets in the keyring.

There is also the consideration of having no password on the login keyring (e.g. for convenience when using a fingerprint for login) and using full disk encryption.

The Security Philosophy page makes a point about avoiding security theater, so I appreciate the clear communication about the limitations.

However the possibility of any process running in my user session reading any secret in the keyring makes me a bit paranoid and looks like the weakest link in my security setup.

So I'm interested in your considerations when using gnome keyring. Also, if you're an applications developer, do you use gnome keyring or are there better ways of storing secrets?

[1]: https://wiki.gnome.org/Projects/GnomeKeyring/SecurityPhilosophy [2]: https://wiki.gnome.org/Projects/GnomeKeyring/StoringSecrets [3]: https://wiki.gnome.org/Projects/GnomeKeyring/SecurityFAQ

As I understand it, embeddings are semantic representations of input data, such as text or images, in a vector space that maps conceptual meaning to distances. However, this vector space is only meaningful to the model.

To draw an analogy, can we compare the model to a hashing algorithm and the embedding to the hash of the input data? If so, what is the equivalent of SHA256?

How can we make embeddings future-proof and exchangeable between independent parties?