Done. It should take a while to propagate to every instance.
Keep in mind tho, this is an unofficial community.
I think you'd be better off using the Boolean XOR tool from the same Split submenu (if you approach it from the Part menubar in the Part workbench), on your cube and your array, instead of the Slice apart tool.
Then on the resultant XOR object use the Explode compound tool from the Compound submenu.
You'll get a folder with all your sliced parts in it.
I am. :)
Most of the subscribers here are new as well since the recent reddit exodus, I'd say that makes them active.
Thoughts?
A single-field-period quasi-isodynamic stellarator configuration is presented. This configuration, which resembles a twisted strip, is obtained by the method of direct construction, that is, it is found via an expansion in the distance from the magnetic axis. Its discovery, however, relied on an additional step involving numerical optimization, performed within the space of near-axis configurations defined by a set of adjustable magnetic field parameters. This optimization, completed in 30 s on a single CPU core using the SIMSOPT code, yields a solution with excellent confinement, as measured by the conventional figure of merit for neoclassical transport, effective ripple, at a modest aspect ratio of eight. The optimization parameters that led to this configuration are described, its confinement properties are assessed and a set of magnetic field coils is found. The resulting transport at low collisionality is much smaller than that of W7-X, and the device needs significantly fewer coils because of the reduced number of field periods.
https://arxiv.org/abs/2205.05797 https://arxiv.org/pdf/2205.05797.pdf
Indeed. However, they are also very slow (usually around 30 km/h) and more importantly very slow to change that speed (cargo ships starts braking 5-10 km before port). The ships' engines aren't doing a ton of work themselves either, per unit of time.
Work per time is power in physics. A ship like this has an engine of about 100 000 horse power per google, which is about 400 cars' worth of power. And 10th of that is about 40 cars. Which matches thereabouts a huge sail in a strong wind at large altitude in the open ocean like this, I think. Back of the envelope math checks out.
In 1957, Valencia experienced a devastating flood that forever changed the city’s relationship with the Turia River. Nearly 3/4 of the city was inundated by floodwater and over 60 people lost their lives. The following year, the city embraced a plan to divert the river around its western outskirts to the Mediterranean Sea.
A park wasn’t the city leadership’s first idea—in an effort to alleviate traffic congestion, they envisioned an elaborate highway system through the heart of the City. But by 1970 the citizens pushed back and protested the highway proposal under the motto “The bed of Turia is ours and we want green!” By the end of the decade, the City approved legislation to turn the riverbed into a park and commissioned Ricard Bofill to create a master plan in 1982. The plan created a framework for the riverbed and divided it into 18 zones. Currently, all but one of the zones has been developed.
The resulting design establishes a monumental 5 mile green swath within a dense and diverse urban fabric, including the historic center of the city, and has an average span of 600 feet, from bank to bank. The park comprises over 450 acres and is characterized by bike paths, event spaces, active recreation fields, fountains, and many notable structures.
A bit more history and a lot of pics of the park in the former riverbed.
Fun fact: now the traffic bridges don't go above the river, they go above the park.
Openstreetmap, for those interested in a detailed view.
Do you know of any other weird parks like this?
A conventional ship with an easily deployable and retractable kite sail system burns less fuel than one without it. It's a type of hybrid vehicle, that has two propulsion methods, the main reliable one, and the supplementary one, for fuel efficiency. With the system installed and the kite in use, the ship saves an estimated 15% of fuel. However:
"There's a structural problem slowing down the process: ship owners (who have to make the investment) often don't pay for the fuel – that's the charterer's duty. The charterer on the other side doesn't charter the ship for long enough a period to make installing low-carbon, but potentially expensive, untested technologies pay back."
The lack of carbon emissions regulations for shipping and low fuel prices have added to these difficulties. The shipping industry is responsible for around 940 million tonnes of CO2 annually, which is about 2.5% of the world's total CO2 emissions.
A company behind these (SkySails GmbH), while technically successful at cutting shipping costs and carbon emissions, has faced economic difficulties. Since then, the company (reborn as SkySails Group GmbH) has switched to land-based airborne wind energy systems for electricity production from high-altitude winds.
What do you think? Yay or nay? Is this technology dead in the water? Not worth the effort? Will we see ships like these in the near or distant future? What needs to change?
Some good reads:
http://www.vos.noaa.gov/MWL/apr_09/skysails.shtml
https://rctom.hbs.org/submission/lets-go-fly-a-kite-skysails-and-climate-change/
Seems like a false dichotomy to me.
Oh, agreed, personally. There's room for all these technologies, and sometimes even a necessity for only some of them, due to a lack of proper alternatives in some places. And it's not always the same technology. There's no one size fits all answer, for every place on Earth.
This is a debate worth having only in a specific localized context, and not to find some generalized rule imo. I never understood why it had to be either/or.
Correct. That's the main supposed advantage of these vertical axis turbines, in the context of offshore.
The lower center of gravity decreases the size of the submerged substructure and therefore also its costs, and there's also the fact a VAWT doesn't need a yaw system.
Main supposed benefit, aside from the supposed windflow benefits, that is:
Which is both explained in more detail in the OP article, and most definitely put in question as well(!).
But yeah, costs are probably even more important than that:
...the larger scale of offshore wind turbines and improved materials indicate that VAWT designs may have certain advantages and benefits for floating offshore wind energy installations. For instance, VAWT designs have a lower center of gravity, which would reduce the platform costs. From a systems perspective, that could be a huge breakthrough for floating offshore wind, where the platform is the single largest contributor to the system cost," said Brandon Ennis, Sandia's Wind Energy Technologies Department offshore technical lead. "The turbine represents approximately 65% of the system cost for land-based wind plants, compared to only around 25% for deep-water offshore sites.
There are downsides too, it's a numbers game. That's why I'm curious what will the full large scale test by SeaTwirl in Norway show.
¯\_(ツ)_/¯
Can't say I have.
However, I originally made this community back in the day when lemmy.ml was basically the only instance, and have since then moved my account to another instance (2 years ago) specifically for those same reasons of lemmy.ml being... hmm.. politically charged.
I didn't think of moving the community until now tbh, but that's not really something I can do. At most I could sticky a link to another community, or delete this one (which would be overkill imo), but for that to happen there needs to be a different community to begin with and community interest for it to happen. The power's all yours people. It's up to you guys to show interest and initiative. Maybe make a post about this, and check if there's interest, discuss where to move etc, a meta post like this is totally fine here on /c/freecad.
Anyway, on a completely unrelated note, the community image did update after awhile, but in the wrong direction! It was the new logo on slrpnk.net/c/[email protected] for awhile, where my account is, but now I see that when the things synced the old lemmy.ml/c/freecad image overwrote the new one on slrpnk.net/c/[email protected]! I guess I can't change the image as a mod from another instance. I will have to mod my old lemmy.ml account here now to change the image (and hopefully it will stick this time around, assuming it works at all) but I will have to make a bug report on github about this when I find the time.
Sorry for the late reply tho.