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malanj

919 karma · joined March 4, 2013

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malanj··on Benchmarking Vision-Language Models on OCR in Dynamic Video Environments
If you're wondering how they prompt the models:

"Perform OCR on this image. Return only the text found in the image as a single continuous string without any newlines, additional text, or commentary. Separate words with single spaces. For any truncated, partially visible, or occluded text, include only the visible portions without attempting to complete or guess the full text. If no text is present, return empty double quotes."

Found in: https://github.com/video-db/ocr-benchmark/blob/main/prompts....

malanj··on Power over fiber
The transmitter module; https://docs.broadcom.com/docs/AFBR-POL2120-DS
malanj··on Why does trying to break into the NT 3.1 kernel reboot my 486DX4 machine?
There's a great gem in the comments too.

[Background: the question author (Michael) answered their own question]

Why is this not the accepted answer - waiting for a better one? – piiperi

@piiperi To me, it feels a bit arrogant to accept a self-answered questions before a couple of days have passed. Granted, on the other hand, in the case of this question, a different answer is quite unlikely. – Michael Karcher

malanj··on Comparison of GreenArrays Chips with TI Micropower Controllers (2010) [pdf]
This comparison looks like bad content marketing at best. "The MSP430 family certainly includes peripheral options that current Green Array chips do not, such as flash memories and timers." => TI's 430 range peripherals is imo one of the primary use-cases.

MSP430's aren't trying to be energy efficient per operation - they are really bad at processing. What they are good at is running complex circuits/peripherals at a low total energy consumption over a long time.

The fact that they're running at 8Mhz is telling... that's far from the "low power" level. As far as I recall, you generally run using internal low-frequency RC oscillator for low power, and then just boot up the high speed crystal oscillator if you really need it.

malanj··on Ask HN: I found a customer with a problem, now what?
I'd recommend finding 5 more people with a problem like that, who're all prepared to sign a Letter of Intent (LOI) that they'll pay you $200/month for it. It's often easy to find a single person like that, but if you have 5, you might be on to something.
malanj··on Not Hotdog App
Craziest thing - it works! Just detected a hotdog (off a photo). Machine learning has really come far, that this can be done for a joke app is really cool.
malanj··on Robinhood stock trading app confirms $110M raise at $1.3B valuation
My understanding is that if you trade through a platform like this, that's monetizing through order flow, you're getting screwed by HFTs. I.e. AFAIK Robinhood doesn't need to be selling the data to HFTs (which they don't do), for you to get screwed by them.

Anyone here in the space who can quantify the "hidden" cost you incur because of more sophisticated traders trading against you?

It feels like working with a broker who's explicitly charging you might actually be cheaper if you take this "cost" into account?

malanj··on Ask HN: How to actually “talk to your customers”?
It (used to be) accessible to any developer on the internet as a platform :-)

Unfortunately, it's shifted to internal use (Journey employees, and enterprise employees).

Also - Thanks!

malanj··on Ask HN: How to actually “talk to your customers”?
Here's a specific anecdote of how I did it in Palo Alto (after just arriving in the US from South Africa):

The first day I was in Palo Alto (and the US), I had absolutely no contacts and was severely jet lagged. I had just moved to the US to establish my startup (https://journeyapps.com) in the US, raise "Silicon Valley VC" and chase the dream ;) tl;dr - JourneyApps is a platform for businesses to quickly developer mobile apps for internal use.

I walked down University Avenue, and spotted Palo Alto bicycles. I walked in (very nervous) and asked one of the sales people if the manager is in. Jeff (the manager), was there and asked what I wanted. I explained I'd just moved here, and was working on a startup that eliminates paper forms.

He was kind enough to not kick me out, and (because it was closing time), spent some time talking to me about how they sell bicycles and which paper forms he uses. He also explained how much of a pain it is.

I kept delving into the details of his business, which he absolutely loves, so he was keen to keep talking. After forming a good idea of what his world looks like, I asked if he'd be keen to do an experiment with us. We'd make an app that does bicycle sales on a tablet, and bring it to him in a day or two. The experiment would be free, he just needs to tell us what works and what doesn't.

He was really keen, and gave me copies of the forms he uses. Overnight we built an app on our platform that acts like his paper forms. The next day we rolled out in his store, and waited for bicycle sales.

The app worked, and we learnt a heck of a lot about US business culture, even though it was just a "small family owned" bicycle store.

Eventually we raised the mythical Silicon Valley VC money and got our first Fortune 100 customers, but the process stayed remarkably similar:

1) Find someone who's passionate about their business

2) Talk to them with genuine interest and learn about their world

3) Be upfront and open about which problems you think you can help with, and which not

4) Over deliver.

malanj··on Root partners with Standard Bank South Africa to offer programmable bank account
We've actually done an Amazon Echo integration :-) So you can do things like check balance, or send money to a predefined set of contacts etc.

A lot of the use-cases getting interest seem to be related to spending management. E.g. company cards for everyone in a team that integrates with Slack. So when you spend on the card it notifies you, and asks you to submit the payment receipt directly on Slack.

malanj··on Root partners with Standard Bank South Africa to offer programmable bank account
There are two ways we're dealing with that at the moment. 1) A sandbox mode to test code on, that simulates transactions without moving real money 2) The idea of "pockets", so you can attach code to a specific ring-fenced pool of money
malanj··on Root partners with Standard Bank South Africa to offer programmable bank account
That'll actually be one of the key use-cases for Root I think.

E.g. We've had people who want a card for their spouse, and then whenever one of them spends money, it alerts the other one so that they can sync budgets.

malanj··on Root partners with Standard Bank South Africa to offer programmable bank account
Not at the moment unfortunately
malanj··on Root partners with Standard Bank South Africa to offer programmable bank account
The account supports EFT payments already
malanj··on Root partners with Standard Bank South Africa to offer programmable bank account
Yes, it's definitely part of the plan. As you can imagine there are a few interesting security challenges etc to solve, but we're working hard on it.
malanj··on Root partners with Standard Bank South Africa to offer programmable bank account
You can sign up to the waiting list at https://root.co.za/ We'll be sending more details to people on that list soon.
malanj··on Root partners with Standard Bank South Africa to offer programmable bank account
It's generally a "read only" view, i.e. you can get account info etc. Root is a "write" API. So you can actually create and modify transactions.
malanj··on Root partners with Standard Bank South Africa to offer programmable bank account
Founder here - let me know if you have any questions! More details at https://root.co.za/
malanj··on Root – APIed bank account for developers
Founder here - feel free to ask any questions!
malanj··on SpaceX set to launch ‘used rocket’
Space shuttle's main engine was the "boosters". A huge liquid (very cold hydrogen and oxygen) tank which supplied the fuel to the actual shuttle during launch, and two smaller solid fuel boosters. The tank and boosters were all destroyed on launch.

SpaceX rockets use a much simpler engines, that burn oxygen and kerosene. The main cost is in the first stage of the engine - think two rockets on top of each other, the first stage is the bottom rocket that first first. When the first rocket is done, it falls away. This first stage accounts for the majority of the cost of the launch. Think of it was being equivalent to the main tank and 2 boosters of the shuttle.

What SpaceX manages, which no-one has done before, is to retrieve that big + expensive first stage for reuse.

malanj··on Overlearning hyperstabilizes a skill by making processing inhibitory-dominant
If you can't get past nature's paywall, and want more detail... https://news.brown.edu/articles/2017/01/overlearn

tldr:

Task: detect which one of the two successively presented images had a patterned orientation and which depicted just unstructured noise.

A first group practiced the task for eight blocks, waited 30 minutes, and then trained for eight blocks on a new similar task. The next day they were tested on both tasks to assess what they learned. The other group did the same thing, except that they overlearned the first task for 16 blocks of training.

On the next day’s tests, the first group performed quite poorly on the first task compared to the pre-test. Meanwhile the overlearning group showed strong performance on the first task, but no significant improvement on the second. Regular learning subjects were vulnerable to interference by the second task (as expected) but overlearners were not.

malanj··on Mathematical genius is fragile
The author lost me at "Mathematical genius resides within every one of us — most people just don’t know it yet."

The movie Ratatouille captured the sentiment much better, "a great chef can be anyone". Which is not the same as "anyone can be a great chef". It seems the author is mixing up those two.

I fully agree that gender, background, schooling, etc is not the key determination of genius. However, saying anyone could be a genius is disingenuous.

malanj··on The Risk of Discovery
I wish pg would start writing longer form essays again. His startup essays had a huge impact on my approach to building startups. They were hugely insightful and inspirational for me.

This essay has a great core insight, and I get you don't need more words to say it, but I still miss the longer ones

malanj··on Arctic farming: Town defies icy conditions with hydroponics
If you're also interested in seeing photos of the setup (and the containers), I found some here: http://www.chicagotribune.com/business/ct-arctic-farming-hyd...
malanj··on Making Humans a Multiplanetary Species [video]
He actually talk about this in the Q&A. Filed under possible "future optimisation".

They didnt think it'll add that much in practise.

malanj··on WhatsApp is going to share your phone number with Facebook
Yes, I found the same (in South Africa, so have to assume that's globally true)
malanj··on Carts without horses
I'm not Kenyan, but South African, but have been to Kenya to look at mobile payments there. Are you sure about this?

My understanding was that M-Pesa started as a domestic remittance solution. Kenya doesn't have a well developed ATM network, so there was a great need for simple and secure domestic remittances (send money home to your family every week type use-cases).

The remittance solution replaced existing methods like sending physical cash with an "agent" (e.g. taxi driver) at high cost/risk or driving/walking very far to a bank branch.

Once the remittance use-case was established, payments was an easy addition, as there was already value flowing through the system.

malanj··on Carts without horses
Payments is an especially interesting example to take in emerging markets. The delta between developed and emerging is often especially huge in payments and banking.

I was part of the founding team of a mobile payments startup SnapScan (http://www.snapscan.co.za/) in South Africa. We had to flip the "US" models around completely. Informal merchants often had no bank accounts and only feature phones, but many consumers had credit cards and smartphones.

We ended up giving QR stickers to merchants, notifying of payment success via SMS and depositing payments in an "instant" bank account that they could withdraw cash from ATMs without a card (just their feature phone).

Looking at how people pay in the US, I would think that our approach wouldn't have made any sense to someone who hadn't seen South Africa (or a similar country) first hand.

malanj··on Perlin noise
When I was in high school I used Perlin noise to create some 3D terrain. Being young and naive I emailed Ken Perlin and asked him some questions about it. To my surprise he responded and was super nice :-)
malanj··on Ask HN: How do you use Amazon Echo?
The app allows you to specify your home city (as long as it's in the US)
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