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phasetransition

810 karma · joined May 19, 2011

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phasetransition··on Ask HN: How to solve the cold start problem for a two-sided marketplace?
Partner as overflow, or undesirable route coverage, for a specific niche market of couriers in your existing location.

Practical examples from a US perspective, where the existing customer has a strong anchor for timely delivery:

1. McMaster-Carr couriers tons of stuff to industrial and commercial facilities. Partner with one of their exist carriers.

2. Local automotive repair shops need parts delivered.

3. Durable medical equipment delivery.

4. Overflow capacity on your local contract FedEx routes.

5. Emergency runs for event or wedding planners.

6. Fresh produce, greens, and fish for restaurants.

7. Airport to hotel lost luggage courier.

phasetransition··on Ask HN: What Are You Working On? (March 2026)
Like an open source JITX
phasetransition··on Shatner is making an album with 35 metal icons
Brooks was a combat engineer at the Battle of the Bulge! That always blows me away. What a life's journey.
phasetransition··on Lessons learned shipping 500 units of my first hardware product
What is your TIM? Do you have a facing secondary on the interface surface?

What finishing process, thickness, overspray, masking requirements does your drawing package specify?

phasetransition··on Lessons learned shipping 500 units of my first hardware product
Given that these went straight to backers, and would have required the final die cast parts to test in the thermal chamber, they probably had not gone to an NRTL at the point the article had been written.

This product is about at the point of DVT in development flow, and therefore would be sent to testing about now. But, instead, being sent to backers.

PS, not a hypothetical circumstance for me. I've previously certified a number of luminaires under UL and CB Scheme. I was the technical chair of ANSI C136.37 for several years, and on the working groups of several other standards.

phasetransition··on Lessons learned shipping 500 units of my first hardware product
There are a number of pressureless casting techniques available. Investment casting is widely used, for instance. https://www.harmonycastings.com/ is a fancier example.

For this specific application, the manufacturing method determines the porosity of the material, and therefore the heat transfer.

CNC prototype parts will have better heat transfer than pressure die cast, and the pressure die cast will perform better than pressureless cast parts.

phasetransition··on Lessons learned shipping 500 units of my first hardware product
Fun read, especially for someone who used to lead engineering for an industrial luminaire manufacturer.

PPAP were developed to help tackle this sort of thing in a somewhat uniform way, but vendor diligence can take many other forms, too.

phasetransition··on Seven diabetes patients die due to undisclosed bug in Abbott's glucose monitors
We changed the entire family diet in part to help him not develop any complexes around food.

We would like to get him in the 5's, and I believe we'll get there. He was below 6.5% every checkup so far except the most recent one.

Between honeymooning and growth hormones, it's difficult to keep him in range from 10pm to 3am, while also not triggering a low after his stomach is empty.

phasetransition··on Seven diabetes patients die due to undisclosed bug in Abbott's glucose monitors
Diabetes for the unfamiliar, in plain language:

1. Insulin helps get sugar into cells. Glucagon gets stored sugar out of the liver into the blood. Diabetes management in 2025 only deals with supplying external insulin.

2. There are several variants of diabetes. Type 1 is an autoimmune disorder where the body attacks the cells that make insulin.

3. Too much insulin equals all the sugar getting sucked out of your blood and lymph and into cells. This is really bad in an acute way. Your brain cannot run without sugar. Accidentally give yourself too much insulin for the sugars and wind up dead or in a coma in short order.

4. Highs are also bad, but generally in a less acute way. There are exceptions, but being too high with blood glucose for a period of time doesn't have the acute risks of being too low. Diabetics (or their caregivers) carry around quick absorbing sugar sources to help against a low.

5. The peak action (fastest reduction in blood glucose level) of the common insulin, in the way we dose it, peaks 90 - 120 minutes after the dose. The long tail is about 5 total hours of action from the point of dosing. So you should give insulin in advance of when you expect digestion to move glucose into your bloodstream. This is tricky. Also, as insulin ages, the peak of the action happens later. If a new vial is 90 minutes, an nearly empty vial might be 120 minutes after dosing for peak action.

6. CGMs, the on-body instrument in question here, are both flakey and amazing. There's a novel of good and bad here. I'm glad they exist, they can be cantankerous. They are a tiny potentiostat, if that is something you happen to be familiar with.

7. Very high blood sugar is treated with extra insulin to overcome the osmotic pressure of having too much glucose in the bloodstream. There's also a lot of chemistry here (glycocalyx to get you started). If your blood sugar is high you generally need more insulin to get past the hysteresis effects. Once the blood sugar starts to come down, that extra insulin is still around, and can cause a dramatic low. CGMs let you observe this, and "catch the low" by eating sugar to replenish the baseline sugar trapped in circulation.

8. Diabetes management is challenge every day, multiple times a day. Especially with small child who doesn't communicate to you about what they believe about their blood sugar. This is my personal circumstance.

9. Endocrinologists have suggested some wild stuff to my wife and I. For instance, keep a tube of cake icing around, as you can administer it rectally to a child who is passed out (or worse) from a deep low blood glucose. This is how poor the standard of care can be.

Father of 4.5 YO son with Type 1 diabetes, and materials engineer by education.

phasetransition··on Seven diabetes patients die due to undisclosed bug in Abbott's glucose monitors
Our almost 5 year old has had T1D for two years. We ended up going the way of a controlled lower carb diet for our entire family. Other than the greatly increased cost to eat this way, it has been transformative for diabetes management of our son, the amount of sleep we get, and the lessened risk of aggressive lows.

We've managed to keep our sons A1C in the 6-7% window after we changed our diet to be heavily carb controlled.

phasetransition··on Loose wire leads to blackout, contact with Francis Scott Key bridge
Can you give an examples of companies that offer this service?
phasetransition··on The Space Shuttle Columbia disaster and the over-reliance on PowerPoint (2019)
We had a meaningful amount of {industrial accident happened} added to the pipeline every year. We made outdoor lighting.

Serious injuries or deaths is a terrible feeling, even if the end result was better safety for the rest of the workers.

phasetransition··on Advice for first-time inventors from a patent engineer
I, too, am not a lawyer, but ended up overseeing the IP portfolio of a publicly traded EU company. Small world...

I comment in geneal support of this advice.

We have started to submit a presentation that would be used for an examiner interview as our provisional application.

phasetransition··on FDA clears first over-the-counter continuous glucose monitor
My 3 year old has type 1, and CGM has kept us out of the ER for surprise lows multiple times.

It also has informed family diet change, in the direction of keto practices, that has compressed the baseline to high delta for our son.

It's a relief to know that an OTC product exists as a backstop to our prescription CGMs.

phasetransition··on How to deal with receiving a cease-and-desist letter from Big Tech
In my personal experience with small firms closed ended matters like wills, contracts, or individual IP filings don't require a retainer.

Open ended matters, like probate, starting an IP portfolio, or response to a C&D trigger a retainer.

phasetransition··on How to deal with receiving a cease-and-desist letter from Big Tech
Most smaller firms will require a retainer. $5k is fairly common. I've been able to work with several large firms for work, and several smaller firms for personal stuff.

Personally, I much prefer the larger firms. In general their work product, responsiveness, and timeliness is well ahead of small firms. They aren't even that much more expensive for some things. Unfortunately I don't know what the retainer $$ would be, if any, for a larger firm.

phasetransition··on How to deal with receiving a cease-and-desist letter from Big Tech
As the (non lawyer) who fell into managing all US legal firm interactions for my day job, I support this list.

If you are comfortable with legal documents; have a law dictionary to understand what specific language means; and read historical case law on the topic in question, you will be well prepared to have a seat at the table with your attorneys.

phasetransition··on Bricks Can Absorb Traffic Noise – Thesis Preso on Helmholtz Resonators [video]
Helmholtz absorbers have been used for some time in built spaces. Look for a pattern of slats or holes like perfboard, often on the rear wall of the space. Lecture halls, museums, performing arts, and the like.

Commercial helmholtz CMU products:

https://www.soundseal.com/masonry

https://www.rpgeurope.com/products/product/diffusorblox.html

phasetransition··on Watsonx: IBM's code assistant for turning COBOL into Java
Son of a COBOL dev... All this virtualization mess, minus the extra Java layer, started back in the 90s, courtesy of Unisys. I remember my dad pulling his hair out when I was in High School, though I did not understand why back then.
phasetransition··on Launch HN: Electric Air (YC W23) – Heat pump sold directly to homeowners
FWIW,

BACnet allows multiple PHY implementations, including 802.3

I suspect that 802.3.cg is also kosher, but haven't looked in detail. It's been 5 years since I looked seriously at whether BACnet was the correct solution for a product family.

Single pair Ethernet is indeed cool tech.

phasetransition··on Launch HN: Electric Air (YC W23) – Heat pump sold directly to homeowners
Upvoted,

BACnet already exists as an ISO standard: https://www.iso.org/standard/37298.html https://bacnetinternational.org/

The example application in the Ethernet Alliance one-pager on single pair Ethernet is HVAC: https://ethernetalliance.org/wp-content/uploads/2020/10/EA_T...

phasetransition··on 80/20 Aluminum T-slot Building Systems – Build your Idea
Kee Klamp for EMT, cool.
phasetransition··on 80/20 Aluminum T-slot Building Systems – Build your Idea
I've used Unistrut and adjacent (flex-craft) more than 80/20. They all have good use cases.
phasetransition··on 80/20 Aluminum T-slot Building Systems – Build your Idea
If 80/20 is new to you, then you might also be unfamiliar with its steel channeled cousin, Unistrut. https://www.unistrut.us/

Unistrut is used extensively in the US to build support structures for electrical switchgear and process equipment. You can get grades suitable for outdoor and corrosives exposure.

Unistrut is the Kleenex term, there are a number of work-alike / fit-alike systems.

Then for round tube, there is Kee Klamp: https://keesystems.com/

phasetransition··on US Department of Energy: Fusion Ignition Achieved
Almost all nuclear weapons rely heavily on fission of the tamper for yield.

Suggest "Ripple: An Investigation of the World’s Most Advanced High-Yield Thermonuclear Weapon Design" from the Journal of Cold War studies to read about a predominantly fusion device family.

phasetransition··on Ask HN: Learning about fundraising as first-time tech founders
Based on your description here, you should have a look at https://tinyseed.com/

Revenue + product + need to support the non-dev stuff is right in the sweet spot of what Rob & co support.

phasetransition··on Mcmaster.com is the best e-commerce site I've ever used
I'm sure they have internal horror stories of the practice, but they do it.

When we sold an old company to a PE group, all the McMaster loose stuff in the warehouse went back to them stacked in boxes on a pallet for them to work through. I wouldn't be surprised to learn our CM did the same thing after the sale.

phasetransition··on Show HN: Windi – knowledge management and sharing platform based on short notes
To me, and presumably other parents in NA and the EU, a Windi is a small plastic tube device that you insert into the rectum of a baby to relieve gas pressure: https://frida.com/products/windi

Is that an intentional homage?

phasetransition··on Apple didn't revolutionize power supplies; new transistors did (2012)
Is there some sort of third quadrant effect, like might be seen for a triac?
phasetransition··on University of Florida gets a 1% cut of Gatorade profits
Long ago I received my undergraduate degree from the University of Florida (UF). I remember when I started college, UF provided us a document that was entitled the IP passport, looked like a passport, and had all the IP related details you ever wanted to read about (which wasn't much for an 18 year old kid). But it was all there in plain language.

UF had (has?) 3 major IP breadwinners, Gatorade, Sentricon termite bait, and a glaucoma drug. Likely as a result, they had a sophisticated IP licensing and commercialization operation. Later, when I went to Georgia Tech, I discovered their technology licensing services were rather amateur in comparison.

There was a time when University of Florida and Florida State University, both state schools, were top 10 ranked for revenue from technology licensure. A professor at Florida State first developed the synthetic chemistry for the drug Taxol.

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