mhandley

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391.
Viewpoint: 'I feel like was accidentally hired'(bbc.co.uk)
10 points by mhandley 6y ago|3 comments
392.
by mhandley 6y ago
One possible solution there would be Green Ammonia, which Iceland is also well placed to produce: https://royalsociety.org/topics-policy/projects/low-carbon-e...
393.
by mhandley 6y ago
It's not cost effective to store for a very long time. If you stored for a year, and the tanks last 30 years, you only get 30 tanks worth of electricity for the price of the tank. If you store for a few hours, you get 30*365 tanks wo
394.
by mhandley 6y ago
I'm on FTTC 80/20. Their control pages (which are excellent BTW) tell me the VDSL sync speed is currently 72.7Mb/s. They allow you to set an FQ/shaper upstream of the DSL infrastructure. I have the shaper set to 95% o
395.
by mhandley 6y ago
I've been a happy A&A customer for 15 years now. They're not the cheapest, but you get what you pay for. Excellent tech support, no nonsense attitude. Edit: as an example, a bunch of years back I detected a routing loop. Ema
396.
by mhandley 6y ago
There really needs to be mandatory insurance for GEO satellites. If your satellite fails to reach the graveyard orbit, the insurance pays the towing fees.
397.
by mhandley 6y ago
The original filing was for reachability down to 40 degrees above the horizon. When they lowered the altitude from 1100 km to 550km, they reduced the angle to 25 degrees above the horizon for the first phase.
398.
Observation of excess events in the XENON1T dark matter experiment(phys.org)
1 points by mhandley 6y ago|0 comments
399.
by mhandley 6y ago
The SpaceX FCC filings indicate reachability down to 25 degrees above the horizon, so it's not clear why 60 degrees was chosen in this animation. I do understand that the satellites are deployed into lower orbits, but satellites from l
400.
by mhandley 6y ago
This map seems to have some inaccuracies. I'm not sure what the circles are supposed to be, but they're wrong for the satellite's coverage limits - looks like they're shown at about half of the actual 940km coverage rad
401.
by mhandley 6y ago
All the satellites in the first phase of Starlink are in 53 degree inclination orbits. This will give them coverage from about 60 degrees North down to 60 degrees South. In later phases they plan to have satellites in higher inclination o
402.
by mhandley 6y ago
The same group that conducted this Dexmathasone study concluded that hydroxychloroquine is ineffective: https://www.recoverytrial.net/files/hcq-recovery-statement-0... "These data convincingly rule out any meanin
403.
by mhandley 6y ago
A typical computer systems research project takes two years, though many take a lot more. After several years research, we write a paper like it's 1920, spend a day knocking together some powerpoint slides, and give a 20-minute presen
404.
by mhandley 6y ago
What's interesting is that I didn't make that video for a general audience. I made it for the networking research community, so I didn't bother to explain what Dijkstra's algorithm is, or any of the basics really. Ther
405.
by mhandley 6y ago
Well, there are gradations to "the wider world". I don't know about you, but I read a lot of stuff that's way outside my area. That's why I hang out here. There's a huge gulf between "suitable for mains
406.
by mhandley 6y ago
The Merlin 1-D Vacuum on the Falcon upper stage is much more powerful than the RD-0124 used on the Soyuz third stage (934 kN vs 294 kN), but uses a single huge engine bell, whereas the Soyuz has four smaller engine bells. I would imagine t
407.
by mhandley 6y ago
Computationally, it's difficult, but I don't think it's intractable. Bear in mind this this is not an animation, but a real-time simulation: https://youtu.be/m05abdGSOxY?t=428 I'm running Dijkstra acros
408.
by mhandley 6y ago
On routing: the best path in this sort of network changes something like every ten seconds or so. To make it work, you need to consider all the links that can delivery good enough SNR, so you're already factoring in rain for example.
409.
by mhandley 6y ago
Using user terminals was as much of a thought experiment as anything. The graphs in the video show you can do pretty well just using a few well placed groundstations - you can shave another millisecond or three off with higher densities, b
410.
by mhandley 6y ago
Thanks - those are my videos. If you've got any questions, I'll try and answer them. One key limitation is that they only model the propagation delay, so achieving those latencies also assumes that serialization delays and queuin
411.
by mhandley 6y ago
There's no doubt that this sort of technology can in principle deliver sub-100ms latencies. Take a look at my analysis here with inter-satellite links: https://www.youtube.com/watch?v=QEIUdMiColU And here without ISLs
412.
by mhandley 6y ago
The research community really should do a better job of engaging with the wider world, irrespective of whether it increases citations. For example, I had this paper in Hotnets 2019, and about 80 people saw my presentation. But I also spen
413.
by mhandley 6y ago
Electricity Map is using 490 gCO2/kWh for UK gas, which is pretty much exclusively CCGT. This does seem high. The US average [1] seems to be around 418 gCO2/kWh whereas electricityinfo.org [2] seems to be using 394 gCO2/kWh
414.
Could the coronavirus crisis finally finish off coal?(bbc.co.uk)
1 points by mhandley 6y ago|0 comments
415.
by mhandley 6y ago
I would definitely agree; even when we're trying our absolute best to get to the bottom of a phenomenon (and from some people's publication counts, it's clear not everyone does that), it's still possible to delude oursel
416.
by mhandley 6y ago
Well done to the three authors who launched an independent peer review of the dataset, and when those reviewers couldn't verify it, asked for the paper to be withdrawn. I'm sure they will always regret they didn't ask more qu
417.
by mhandley 6y ago
This process doesn't capture carbon, it captures CO2. Splitting CO2 back to Carbon and Oxygen does indeed take a great deal of energy, but if you can efficiently and cheaply store CO2 permanently (underground, in concrete, in greenhou
418.
by mhandley 6y ago
No, this captures carbon dioxide. Turning carbon dioxide back into carbon is not part of the process. You still need a way to store the CO2 permanently.
419.
by mhandley 6y ago
OK, I'd missed that. That this is primarily a Cisco misconfiguration issue didn't really come across in the Cert bulletin.
420.
by mhandley 6y ago
The cert alert seems to imply this is a general vulnerability, but really it mostly seems to be a default misconfiguration enabling IP-in-IP on a few products. I just modified the PoC and did a scan of my home network, which has a pretty

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