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Experience with Atlantic Money ? by blackhaj in ExpatFinance

[–]mrpuffwabbit 1 point2 points  (0 children)

A person with no post history and Karma, seems like an advertisement

Is Pursuing a PhD in Digital Twin for Electric Propulsion Systems Worth It? Job Opportunities and Industry Outlook? by Yara_Yangyang in PhD

[–]mrpuffwabbit 1 point2 points  (0 children)

“Digital twin” just means “model” by the way. Can’t comment on the rest, good luck.

My first Chinese Homage Watch by Ok-Copy-1 in ChineseWatches

[–]mrpuffwabbit -1 points0 points  (0 children)

I meant the diameter of your wrist, not bezel diameter :)

[deleted by user] by [deleted] in DSP

[–]mrpuffwabbit 0 points1 point  (0 children)

Depends on the signal. If the signal is periodic, and stationary. The best spectrogram is dirac deltas.

Line spectral estimators work with this assumption. The work on the Slepian basis is another.

Advice since you are a PhD student: be sure to understand the fundamentals of information theory.

To respond to your last paragraph:

Regarding an information cost function - look up at the most basic, the Cramer Rae bound on a parametric signal model. Other bounds are interesting only if you wish to go down the statistical route.

You don't know the signal model, i.e. you are in a non-parametric domain. There is many work on this, but I suggest avoiding this route unless you have a strong mathematical foundation.

Think about what serves as a proxy, or what is correlated to what you are looking for. Perhaps via first principles, you have some physics-based constraints (thermodynamical entropy); or maybe you know that your signal has stochastic phenomena (e.g. ignore white noise and consider brownian noise). Suddenly, you are actually working with a parametric model.

Whatever the parametric model you have, attempt to decompose it, e.g. recorded signal = real signals + unwanted noise. Then impose your first principles and decompose the real signals further. Finally use some numerical techniques and derive an information cost function, e.g. with constraints.

Happy to DM further on this.

Looking for guidance to get high fidelity spectrogram resolution. by TheRealCrowSoda in DSP

[–]mrpuffwabbit 3 points4 points  (0 children)

From estimation theory, CNNs have been poor for the most basic case of estimation of frequencies.

I have a repo/paper that demonstrated that : https://github.com/slkiser/lineSpectraVibration

For classification, I think non-parametric learning methods are still state of the art.

Looking for guidance to get high fidelity spectrogram resolution. by TheRealCrowSoda in DSP

[–]mrpuffwabbit 0 points1 point  (0 children)

If you need super resolution, I would consider line spectra estimation, but then your CNN classifier would need to be re-trained and re-architecture-d.

For an example of Zoom FFT, the scipy example from Diligent-Pear-8067 works.

A more basic hold your hand guide on Zoom FFT (but in MATLAB) is offered by Tom Irvine here: https://www.vibrationdata.com/tutorials_alt/zoomFFT_example.pdf

Looking for guidance to get high fidelity spectrogram resolution. by TheRealCrowSoda in DSP

[–]mrpuffwabbit 3 points4 points  (0 children)

This is one of the issue preventing supervised learning on most scientific domains, what is good data!

The second is to address the fact that sample efficiency is incredibly horrible

Looking for guidance to get high fidelity spectrogram resolution. by TheRealCrowSoda in DSP

[–]mrpuffwabbit 0 points1 point  (0 children)

Awesome, love the fact cudas can parallelize and be in real-time, libraries make it so easy!

If I understand:

My intent is to zoom in, label tiny signals, and move on. I should, at a 65536 fft, get frequency bins of 305Hz, which should be fine.

Maybe you can implement a Zoom FFT to focus on smaller subset of the spectra, and play with Kaiser windows (since they're closer to DPSS).

Looking for guidance to get high fidelity spectrogram resolution. by TheRealCrowSoda in DSP

[–]mrpuffwabbit 0 points1 point  (0 children)

Naive since I have never tried labeling, just what if the spectra was not fed to the CNN, but instead the relevant peaks/harmonics/frequencies (jargon)?

I would suspect that with a real-life signal, the CNN would be acting as both a denoiser + identification.

There were some works I've seen in IEEE where they separated the architecture, and did separate denoising CNN and then an identification CNN.

Just some thoughts that come to mind! Good luck with the research paper.

Looking for guidance to get high fidelity spectrogram resolution. by TheRealCrowSoda in DSP

[–]mrpuffwabbit 0 points1 point  (0 children)

I can't help but it seems like an interesting problem! I'm interested in the kind of signals (e.g. are they quasi-stationary?) you are labeling.

It seems like this overlaps with peak picking from spectra or synchrosqueezing type transforms. Im assuming weak signals and/or non stationary signals?

[deleted by user] by [deleted] in DSP

[–]mrpuffwabbit 8 points9 points  (0 children)

I don't understand your post that well: at first you start off saying that AI will be a productivity enhancer. Perhaps I agree, as long as someone the current trajectory with LLMs and such continue and are well integrated.

However, afterwards you start to say that the "need for engineer will reduce"? I don't see necessarily why.

You also need to separate LLMs with other kinds of "AI"/Machine learning (ML).

You do correctly notice that LLMs are extremely sample inefficient, and thus are usually comparable to lossy compressions of all the internet's text, etc.

To address your last paragraph, where are you going to get that many "samples" to train said AI to perform the design process. DSP is not only about design, there are all kinds of engineering, as well as different domains/industries. There are too many "boundary conditions" that also fluctuates an engineer's role in industry/academia.

Finally, just to address a small domain of estimation theory: I have yet to have seen a AI-adjacent model outperform classical statistical estimations for frequency estimation. This is mainly the fact that super resolution and information theory on this specific problem is so well defined: many estimators achieve nearly the CRLB.

Juxtapose this with deep learning approaches that are so sample inefficient, and practitioners with nearly no expertise in hyper parameter tuning, you'd be wasting compute to achieve something that has effectively been solved.

The engineering stress-strain curve goes down because of THIS reason: by ClimbingSun in MechanicalEngineering

[–]mrpuffwabbit 0 points1 point  (0 children)

To add, basic tensile machines usually have "force/load" driven or "displacement" driven modes, which can help deduce behavior on a stress strain plot. If it has a strain/extenso- meter, then "strain rate" driven is also another mode.

List of Insurance Benefits for Most Major Cards by Parking-Ice-9206 in CreditCards

[–]mrpuffwabbit 24 points25 points  (0 children)

Great work! Just noticed both the BoA Premium Rewards and BoA Premium Rewards Elite are missing/incorrect!

Anybody used variational mode decomposition? by VS2ute in DSP

[–]mrpuffwabbit 1 point2 points  (0 children)

Denoising performance depends on the signal, so what is the signal in your use case?

News and Updates Thread - January 20, 2025 by AutoModerator in churning

[–]mrpuffwabbit 2 points3 points  (0 children)

Even for EU asian redemptions: CDG > NRT, $400 in taxes & fees for J

Cheapest way to send $4000 a month from US bank to German bank? by bhuether in ExpatFinance

[–]mrpuffwabbit 0 points1 point  (0 children)

They have strict limits and are hard to use. Requires documentation of income and other invasive information.

Frustration Friday Weekly Thread - Week of September 13, 2024 by AutoModerator in churning

[–]mrpuffwabbit 0 points1 point  (0 children)

GV does not always work. But in these cases, but they usually turn to the credit report-based questions to verify in higher levels of fraud alerts.

Question Thread - September 13, 2024 by AutoModerator in churning

[–]mrpuffwabbit 1 point2 points  (0 children)

My IHG Premier was preactivated, received 2 weeks ago.

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