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Hacker News

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Logo of telegram channel hacker_news_feed — Hacker News
Channel address: @hacker_news_feed
Categories: Technologies
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Top stories from https://news.ycombinator.com (with 100 score)
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The latest Messages 987

2021-02-23 04:20:09 Tasks, microtasks, queues and schedules (2015) (Score: 100+ in 11 hours)

Link: https://readhacker.news/s/4Fkqs
Comments: https://readhacker.news/c/4Fkqs
411 views01:20
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2021-02-23 03:50:01 ZZT: Epic’s First Game (Score: 102+ in 10 hours)

Link: https://readhacker.news/s/4Fkzu
Comments: https://readhacker.news/c/4Fkzu
445 views00:50
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2021-02-23 01:00:18 30K Macs are infected with ‘Silver Sparrow’ virus and no one knows why (Score: 100+ in 4 hours)

Link: https://readhacker.news/s/4Fmqy
Comments: https://readhacker.news/c/4Fmqy
879 views22:00
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2021-02-23 01:00:15 Unsuck It (2010) (Score: 100+ in 4 hours)

Link: https://readhacker.news/s/4FmiN
Comments: https://readhacker.news/c/4FmiN
807 views22:00
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2021-02-23 00:40:08 Show HN: Call a Dev – Pay Stack Overflow users $1/min for live programming help (Score: 102+ in 4 hours)

Link: https://readhacker.news/s/4Fm9P
Comments: https://readhacker.news/c/4Fm9P
835 views21:40
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2021-02-23 00:30:12 Launch HN: H3X (YC W21) – High power density electric aircraft motors (Score: 102+ in 7 hours)

Link: https://readhacker.news/c/4Fkup

Hey HN!
I’m Jason, one of the co-founders at H3X (https://www.h3x.tech). We are building the lightest electric propulsion systems in the world. Our first product is a 250kW (330HP) integrated motor drive in a 18kg (40lb) package. It combines the electric motor, inverter, and gearbox into a single unit, resulting in an ultra-high-power density solution for electric aircraft (and other mass sensitive applications).
In terms of electrification, we believe the aircraft industry is where automotive was ten years ago. There are many companies working on eVTOL and single-seaters, but very few are working on large commercial single-aisle electric aircraft such as a 737. This class of aircraft is absolutely critical to electrify as it accounts for the most passenger-miles [1] and is the biggest slice of the pie in terms of aviation emissions. Beyond the environmental impact, there are huge potential cost savings from both fuel (or lack thereof) and reduced maintenance for airlines.
Aircraft are very mass sensitive so there are two main technology challenges that need to be solved to enable this class of electric aviation –
(1) High energy density and efficient energy storage (batteries, hydrogen fuel cells, etc.)
(2) Light, efficient, and high-power density electric propulsion systems (electric motors, power electronics, gearbox)
There are many people working on (1) and great strides are being made [2][3]. We are focused on solving (2). A study done by the DOE determined that for a 737 to complete a five-hour flight, the propulsion system must be >12 kW/kg [4]. Today, best-in-class systems have a power density of 3-4 kW/kg. With our first product, we are targeting 13 kW/kg, making it an attractive solution for near-term Advanced Air Mobility (AAM) applications as well as an enabling technology for the aviation industry to enter the next stage of electrification.
There are some cool things we are doing with the electromagnetics, power electronics, and the integration between the systems to get to the 13 kW/kg. There is not a single magic bullet, but rather a combination of multiple technological advances - 3D printed copper stator coils, high frequency SiC power electronics, and a synergistic cooling system to name a few.
Our origins in electrification stem back to our college days where we built Formula-style electric racecars (s/o to Wisconsin Racing FSAE!). During year 1 of the program, we got so fed up with our COTS motors and inverters, we decided to go clean slate and build our own from the ground up the following year. Those were super happy fun times. Lots of dead IGBTs and all-nighters in the shop, but in the end, we got everything working and delivered! It was a true test of resilience and taught us how to GSD. Great preparation for starting a company. This led us to grad school and it became apparent during this time that the electric aircraft industry was a sleeping giant ready to be woken. We felt uniquely positioned to capitalize on this opportunity, so after about a year in industry, we left our full-time jobs and went all in.
We’ve got a long road ahead - aviation is tough, there’s no denying that. In addition to the engineering challenges, there are also major certification barriers. However, CO2 is a serious problem and right now the major aviation players don’t have a compelling plan to meet the goals laid out in the Paris Agreement. Innovation needs to come from the outside and that’s what we’re doing at H3X.
I’d love to hear your guys thoughts and would be happy to answer any questions you have.
Sources:
[1] https://www.transtats.bts.gov/tables.asp?DB_ID=130
[2] https://www.theverge.com/2020/9/22/21449238/tesla-electric-c...
[3] https://hypoint.com/, https://www.plugpower.com/
[4] ASCEND DE-FOA-0002238
811 views21:30
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2021-02-22 23:50:11 Mars 2020 Descent and Landing Video ( Score: 108+ in 1 hour)

Link: https://readhacker.news/s/4FmXq
Comments: https://readhacker.news/c/4FmXq
11 views20:50
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2021-02-22 23:00:01 A quarter of the known bee species have not been sighted since 1990 (Score: 101+ in 2 hours)

Link: https://readhacker.news/s/4Fmsu
Comments: https://readhacker.news/c/4Fmsu
465 views20:00
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2021-02-22 22:20:01 Why Discord is switching from Go to Rust (2020) ( Score: 105+ in 1 hour)

Link: https://readhacker.news/s/4Fmjm
Comments: https://readhacker.news/c/4Fmjm
694 views19:20
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2021-02-22 21:30:16 Opinion: We’ll Have Herd Immunity by April (Score: 101+ in 1 day)

Link: https://readhacker.news/s/4Fhuw
Comments: https://readhacker.news/c/4Fhuw
860 views18:30
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