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Joined 3 years ago
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Cake day: July 2nd, 2023

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  • Is that something you’re looking for? As a practical matter, the effort to maintain multiple release branches and backports – compared to the norm of just maintaining a single main branch – is an outsized effort, available to only well-funded FOSS projects, usually by having an industry sponsor that makes it a priority.

    I posit that the grand majority of selfhosted FOSS software, by project count, do not have back ported branches. And so production environments will want to set up an offline validation setup to evaluate update, prior to making the switch. Not convenient, sure, but not exactly insurmountable either.

    At some point, some amount of responsibility for use of FOSS software must fall upon the users, or else the project is less about creating value by building up the commons for software, and more on the exploitation/abuse of the volunteers.



  • There are indeed places where large amounts of human activity takes place underground, often being metro systems and their associated retail spaces; Tokyo Station in Japan comes to mind as having an underground mall attached to it.

    But the same caveats for underground construction of transportation systems also apply to all other underground structures that humans would like to build. Consider the differences between ground conditions in: the San Francisco Bay Area, Denver, and New York City.

    The Bay Area is the outlet for major rivers in northern California, bounded by mountain ranges on virtually all sides. The surface is either a thin covering of soil atop this mountain rock, or is a layer of looser soil or mud, made from the sediments carried in by those rivers. This makes for fantastic agricultural conditions but presents a real risk of liquifaction when there’s an earthquake. While an underground structure wouldn’t fall over – because it’s within the ground – it could certainly lose its supports unless it has piles all the way down to the rock. And that’s only buildable on the narrow shoreline region where there’s sufficient depth before hitting the rock layer.

    With Denver, it’s basically all rock, so to build within the rock would require blasting it away and building within the hole, or to build normally then bury the structure in fill, so that it’s below grade.

    With NYC, it’s a different story because the ground conditions make it fairly easy to dig tunnels and drive piles, and the bedrock layer beneath Manhattan is strong enough to support the weight of supertall-class skyscrapers. On this point, the New York Fed’s Gold Vault is in the basement in Manhattan, precisely because the volume of gold inside would be a serious strain on any foundation and the geology beneath.

    All that said, the surface conditions in some extreme climates may warrant building underground, or avoiding the underground outright. Burying a dwelling in New Mexico would make a lot of sense, due to the hot and dry Southwestern climate. But in Alaska, an underground dwelling would cause melting of the permafrost layer below, resulting in a similar situation to liquefaction. I suppose this can be mitigated, but it would be a monumental effort, akin to Camp Century in Greenland. That project was abandoned due to changing ice geology.


  • I generally shy away from downvoting even things I dislike. I don’t want to fall into an echo chamber where all I see are only the things I agree with.

    This is not how Lemmy works. If you don’t ever up or down vote anything, and if you have your client hide the up/down votes on all comments and posts, you will still see the same content as someone who prodigiously votes. Votes here are, in the truest possible way, optional.

    But for people who do utilize up/down votes, they are a signal. Sometimes they’re a weak signal, sometimes a bad signal, and yet other times might be a strong signal from the community. How to evaluate the signal is a matter of continued debate.

    Now, as an aside, a major difference in the Fediverse compared to commercial social media networks is that the block functionality here is used for more than just dodging abusers. Precisely because there is no algorithm, blocks and mutes are how users curate what they don’t want to see. This alone does not create a so-called online echo chamber, the same way that most people don’t want to see a steaming pile of poo on their morning walk. People reasonably deserve to have a pleasant experience online. And depending on their life circumstances, this might be a lot better than their IRL situation.



  • Then there is the modern usage of the terms which seem to vary based on who invokes the[m]

    I think the thing to keep in mind is: 1) words evolve over time, and 2) the people using those words might be abbreviating what they actually mean, because they don’t know that there’s another related concept that is named similarly. The best example of the first is how “truck” in the 1910s meant what we now call a “hand truck”, and “car” from that era meant traincar. Whereas in the 2020s, “truck” and “car” both refer to automobiles, and we had to create the backronyns of “hand truck” and “rail car” to avoid confusion.

    I don’t think your theoretical understanding of Marxism is wrong – though I’ve not read enough to confirm – but I would hazard against using other people’s wrong definitions and usage guide your own understanding. If you understand the ideology, then it’s a matter of rendering it using the right words; that is, it becomes a communications problem.

    For example, Republican politicians will use the term socialism to mean communism and vice versa

    I would especially not suggest relying on right-wingers to properly use – let alone understand – left-wing ideology, since their objective is to denigrate leftists through FUD and infantile repetition. Basically, the maxim of “if enough people are ‘talking’ about something, it must be controversial” or “I’m just asking questions bro”, neither of which are anywhere approaching a good-faith discussion on the merits.

    Some politicians like Mamdani or Bernie will describe socialism to mean a more humane type of capitalism that has other priorities other than pure profit seeking

    How the two use the word “socialism” is almost always understood as a shorthand for what Europeans would call “social democracy”. So it’s definitely on the list of valid implementations of socialism, but is specifically about reforming an openly capitalist system into something more egalitarian. That said, “social democracy” still leaves out a lot of details which need clarification: do Mamdani or Bernie support (re)building the social safety net? Does the state need to also own railroads the same way that they own highways? For the former, there’s the standalone word “welfare state”, but I’m not aware of a compound phrase that means “social democratic welfare state”, if that even describes Bernie or Mamdani at all. I’d certainly love a word that means “social democratic welfare railway state” but nothing has caught on.

    I think that should underscore my point: even after resolving exactly which word they might be abbreviating, there aren’t enough short words to succinctly describe any particular ideology. Rather, the words are useful to get a rough idea of a person’s views, but ultimately, every one and every candidate is going to have a slightly different take on certain questions.

    Some people use communism to describe an authoritarian system that has no regard for human agency

    I personally refer to this definition as “Stalinist communism”, because it does accurately describe how the USSR was operating under Stalin. Essentially, it wrapped a cult-of-personality in the trappings of communist thought, though people like Trotsky pointed out how communism could be done much differently. Obviously, history is quite clear that the Stalinist approach was not adopted as-is by any other country, nor retained in the USSR after Stalin’s death. Indeed, I’ve never come across anyone who genuinely refers to themselves as a Stalinist or who seriously proposes to the adoption of Stalin-style, top-down authoritarian communism. Maybe some right-wing Russians do, but idk. My point is that, like the Republican examples above, Stalin and authoritarian communism is usually only brought up as a “thought terminating answer” rather than to seriously debate the merits of communism, either theoretically or practically.

    multiple people will have multiple definitions that most often don’t align with how Marxists describe communism and socialism

    Yes, because they’re usually talking past each other about different things. Being able to detect which definition someone means to use, that’s a skill that you can develop for yourself, to have a clearer picture than they do.

    I’m primarily writing this comment because I abhor the idea that an idea – it could be anything, from rocket science to theorrtical mathematics – is perceived as being an arena where everyone is just making up stuff, and if that should lead to people becoming turned off the idea of studying it for themselves, that’s a net-negative. No doubt, some countries, politicians, and agencies want to denigrate or prop up their own definitions, but that just makes it easier to identify fake socialists and “communists in name only”.

    The merits and failures of socialism and communism deserve to be comprehensively hashed out in the public mind, and it only serves the status quo that this not happen. And the longer the conversation is delayed, the more that the indisputable ails of the status quo will take more victims.




  • litchralee@sh.itjust.workstoNo Stupid Questions@lemmy.world*Permanently Deleted*
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    6 days ago

    Despite the USA being somewhat of a political pariah at the moment, it has long been the case that American universities are desirable from an educational perspective and for “clout”. Not to say that TU Delft or anywhere else doesn’t have name recognition, but being a fully English instruction on a continent with few neighbors, it is a very “exotic” destination to go study at.

    With Hollywood and media hyping up the American collegiate experience (eg red Solo cups, fraternity/sorority life, binge drinking, road tripping for spring break, etc), even some non-research public college systems like the California State University (CSU) system will receive international students, while the research-focused University of California (UC) systems remains in the top tier of public American universities, making it extra exclusive, akin to the East Coast’s Ivy League schools.

    From the university’s perspective, they have a commodity they can market to an international audience, so why not charge more? As for why these colleges are behaving like capitalists – especially the public universities – it is because of chronic state underfunding: the USA federal government does not pitch in very much to the universities, except as research grants. And when push comes to shove, state legislators will cut university funding, meaning more has to be paid for by students. Some states even slash school funding and then try to replace it with state lottery proceeds, which means schools are only well-funded when there’s a gambling epidemic…

    Now in your case, it should be noted that the University of Southern California (USC) is a private university, that regularly jostles with UCLA (a UC campus) for the highest ranking as a college in southern California. Accordingly, they are priced similarly for international students but not for domestic students: the UC system first-and-foremost must serve its constituent citizens, so to keep tuition low for in-state students, they will raise the price of out-of-state or international students. USC and other private colleges would follow suit, because free extra money.

    We haven’t privatized the public universities in the USA, but they’re almost operating as though they already have been, charging as much as the market can bear.


  • it’s negligible compared to the load carrying provided by the tire pressure.

    My comment was in reply to the “always equal” assertion, which it definitely is not. No doubt, it’s a handy rule of thumb but nobody should walk away thinking it is a hard rule of tire physics.

    And that’s the gyroscopic effect, not any of the other things that contribute to bicycle stability but don’t depend on wheel size.

    Correlation does not prove causation. You assert that bicycle wheels are big because they have more gyroscopic effects. That is a correlation. I assert in my other comment that small wheels would be swallowed by potholes. That is a causal relationship: the wheel must be bigger to deal with real roads AND is something a smaller wheel cannot handle. It is a fact that a big wheel rolls over protrusions and holes that a small wheel would fall into.


  • The premise of my question is that it is a false dichotomy: there need not be tension between pedestrian and roadway users if the drainage system spread out the water over a larger area of already-paved surface. Everyone wins!

    In a rural area where roads are already narrow, this wouldn’t work and I acknowledged that in the title, limiting the inquiry to urban/suburban. I agree 100% that rural country roads built with ditches are entirely appropriate, cheap, and allow natural absorption into the soil. But urban streets aren’t just souped-up country roads and need to be constructed for the built environment.

    Whereas rural areas prioritize land, livestock, and the great outdoors, urban areas prioritize people. And that means pedestrian facilities are non-negotiable in my book.


  • The TL;DR is that at one point in history, automobile wheels did in-fact use the same construction as bicycles. But the needs of automobiles diverged somewhere in the first half of the 20th Century. And since tires are mounted onto wheels, we need to discuss those first.

    I’ve written prior comments here about bicycle wheel/tire fitment and wooden carriage wheel design.

    Basically, early horseless carriages used the same wooden wheels that horse-drawn carriages had used for centuries, which have a squared off profile that contacts the ground, sometimes with a steel band – a tyre – to both hold the wheel together and reduce wear on the wheel itself. The only requirements for carriage wheels were to: 1) roll, and 2) bear weight. And using thick wooden spokes, a wagon wheel could achieve those objectives just fine but were really heavy.

    When the bicycle was invented in the 1820s, the first iterations used slender variants of wagon wheels, but since 100% of the moving power came from the human rider, this is still unnecessary dead weight to haul around. So bicycle wheels evolved to use very thin spokes, which by the late 19th Century were made of steel in tension, rather than the compressive loads through wood that wagon wheels used. Although steel is heavier than wood, a thin steel spoke has more tensile strength than the same weight of wood has in compression. So overall, it’s a weight savings. Specifically, we say that a bicycle wheel must: 1) roll, 2) bear some weight, and 3) allow for leaning.

    The last requirement is crucial for bicycles: they cannot use squared-off carriage wheels, or else leaning the bike will start riding on the edge of the wheel/tire. The solution is simple: round off the contact point so that leaning doesn’t change the profile.

    As it turns out, by the 1910s or so, automobiles also realized that wooden wheels were too heavy, and so they also adopted the steel spoked wheel. But they kept the squared off rubber tire, precisely because an automobile does not (normally!) lean during a curve, and instead should be firmly planted on all four wheels. So at this point in history, both automobiles and bicycles are using spoked wheels but just have different shapes for their rubber tires. Great!

    But this wouldn’t last: the spoked wheel – which already is a phenomenal structure, essentially being a suspension bridge wrapping upon itself – has one small quirk which bicycles tolerated but automobiles do not. When a spoked wheel is subjected to a straight downward force, the structure distributes the force essentially evenly. But if the force is sideways from the left (ie pushing leftward at the axle), the spokes on the right are heavily stretched but the spokes on the left aren’t. This is uneven loading, that then reverberates from side to side.

    This is no issue for bicycles, because they usually lean and so the sideways force is often zero. Sure, a BMX rider can intentionally ride the bike askew, but it’s workable. For an automobile, sideways forces are a regular occurrence, such as during a sharp turn. But also during motorsports where the car is sliding. Spoked wheels can disintegrate when subjected to enough sideways force, which is why cars switched to wheels using sheets of steel rather than spokes. This added weight but was necessary.

    Also around this time, cars got very heavy – some would say “land yachts” – and this required making the tire wider to deal with the weight. Since the tire and wheel are the same width in cars, this means wider rims as well. Bicycles have no such issue, because most bicycle tires are “balloon shaped”, and so already are wider than the rim, sometimes almost comically. From a purely materials perspective, making the rim match the tire width does not add strength but does add weight, so cars have to accept that penalty but bikes do not.

    In the end, the closest that bicycles and automobiles got was in the early 1900s, and have diverged ever since. Fatbike bicycles and now ebikes pushed the width of tires to some 4+ inches (100+ mm) while touring cars are luxury vehicles meant for long distance, high speed cruising on the Autobahn, and so need wide, high aspect ratio tires.

    As for wheel diameter, that’s much simpler to answer: as Jeremy Clarkson noted in the Vietnam Top Gear Special, smaller wheels fall into potholes easier. Bigger wheels roll over them. Automobiles for paved roads use modest diameters, capable of slowly rolling over a 4-6 inch curb to access a driveway. The same diameter on a bicycle would be the 27-inch (aka 700c) or 29-inch class used for road cycling or mountain biking. Whereas smaller folding bikes used exclusively for last-mile commuting can tolerate smaller wheels, because the benefit doesn’t outweigh the diameter penalty when folding it down. All the meanwhile, a motor scooter (eg Vespa) also has small diameter wheels, because they don’t go as fast and urban streets are paved.

    For overlanding or bouldering, 4x4 automobiles have some enormous tire diameters and even then, they sometimes have to intentionally reduce the air pressure, so the tire can conform to rock surfaces and thus get more traction. But such tires are wholly inappropriate on a roadway at freeway speeds.


  • I agree with everything up until this point:

    If the road were sloping towards drainage at the centre, then floodwater fills the entire road basin before overflowing, and your road is blocked

    I’m imagining the scenario of a residential suburban neighborhood, on mostly flat land. With moderate rain and fallen leaves from the Autumn, some storm drains will clog and need manual intervention. If this neighborhood were built with conventional crowning, then the properties unlucky enough to be next to a clogged drain will see some flooding, but other homes in the neighborhood will have no issue.

    If instead the entire neighborhood used center gutters with center drains, but spaced the drains closer together so the drains/km is identical to a conventional build, then the same rainfall should cause smaller impacts, because: 1) a single clogged drain will only flood a small patch of the road, until 2) reaching the next open drain, which is closer and thus the flood is a smaller area, and 3) does not disadvantage the unlucky property immediately adjacent to the clog, since the flooding is concentrated at the road center.

    In both constructions, the road area is identical, the rainfall is identical, and the storm drain capacity is identical, yet the latter needs only one half the linear gutter distance and can spread out the flood risk across the whole neighborhood. Phrased another way, center gutters should stave off flood damage to any property, until such point that the drainage is simply overloaded and then every property would flood. No more “lucky” or “unlucky” neighbors: either everyone is safe or they all need to evacuate.

    That’s the situation in a flat neighborhood, but in a sloped neighborhood, center gutters aren’t any worse: the most critical drains are at the bottom of the neighborhood. If those fail, it’s still game over for those adjacent homes. And that still is the case for side gutters anyway.


  • The pressure the tire exerts on the road is always equal to the pressure it’s inflated to.

    This is merely a convenient approximation for properly-inflated tires carrying a load, not a hard rule rooted borne out during empirical examination. After all, removing a wheel from an automobile and rolling it along clean concrete leaves tire tracks that are full width, yet the tire will not substantially deform at the contact point because 20-30 pounds is not much of a burden. If there’s no deformation, then the contact patch is a line with a tiny area, which would wrongly suggest a ludicrously high tire pressure.

    because they have more gyroscopic effect and thus make the bike easier to balance.

    While bike wheels do act as gyroscopes – as do all rotating masses without a contra-rotating mass – this is not substantial to bicycle stability. If it were, kick scooters or e-scooters which have substantially smaller wheels but with the same physics as bicycles would be unrideable.

    The bicycle has existed for about 200 years, and for most of that time, how it remains stable was an open question in physics until roughly the late 20th Century, when researchers built enough intentionally-bad bicycles to prove what was minimum and sufficient to have a functioning bicycle. This empirically ruled out trail, caster, and gyroscopes as necessary factors. But the most prominent factor that remained necessarily is centrifugal balancing, aka leaning/banking. Turns out, bicycles lean into curves just like airplanes so.


  • it becomes more problematic at the center.

    This is precisely what I’m trying to understand: what gets more problematic? The driving? The civil engineering? What is the exact complexity that a center drain would introduce?

    some one has to go unclog it.

    Conventional drains along the curb also need to be unclogged manually, except that the public works dept needs to get people to move their parked cars, which can also hide the problem from being easily noticed in the first place.

    either have to shut down both directions or be at risk of being hit from both directions.

    From seeing how my town accesses manholes located in the middle of a two-way road, they arrange two heavy trucks in a row, one before and one after the manhole. On a multilane arterial, this is a minor traffic disruption of one lane. On a quiet residential street, people just go around slowly.

    with the way roads are constructed, it would be a lot more expensive to design the sewers to either tolerate the loads (imagine a big heavy truck,)

    I believe that roads are infact designed with the sewer and storm drain pipes directly below the traffic lanes. See my other comment. A cursory review of my town’s planning documents for a new road extension shows a cross section that has all longitudinal piping underneath the lanes, so that the manholes aren’t installed under sidewalks or the curb. I am open to seeing plans for other jurisdictions that build their pipes differently.



  • I would question why road traffic is driving very fast in “heavy rainfall”, but the solution is the same: truncate the center gutter before the intersection, so that the intersection itself drains conventionally, into the center gutters on all approaches to the intersection. Alternatively, where it makes sense, use a center drained roundabout.

    having a hollow space beneath the part of the road that needs to support the most weight of vehicles

    My understanding is that there is only one storm drain pipe underneath a street, somewhere near the center, and each side of the road has laterals that connect to this pipe. There are not two pipes, one for each side of the street directly under the edges of the paved surface. If it were literally under the curb, service manholes would be impossible. See https://www.amwua.org/blog/only-rain-should-go-down-the-storm-drain (relevant image only shows up on desktop mode)



  • I’m not sure I understand the issue with fortifying the edges – urban roads are generally sealed asphalt, continuous from curb to curb, and I’m not suggesting any sort of exposed soil (except for storm water impoundment).

    For the inward slope, I’m struggling to understand the issue, since road crowning is already very slight. A center drain would not require a noticeably visible slope, since the physics of rainwater are the same, just that it’s sloping toward the center instead of the edges.

    The concern about single point of failure is noted, but I think it should be possible to halve the distance between center drains, since this would have an identical number of storm drains per km of road. Plus, unlike side gutters that are interrupted at every intersection due to crossroad crowning, a center gutter could spill over to a cross street’s center gutters; now a flood would have to clog all the drains in an area, which would be catastrophic no matter if center or side gutters.


  • I did consider this possiblity, but I figure that such a center drained road would necessarily have excavated more material from the road than a conventional crowned road, so the road itself sits lower than the nearby properties, and lower than a crowned road.

    If done like this, the road necessarily has more “storage” capacity during floods than whatever could fit into the shallow side gutters of a crowned road. If the issue instead is clogged drains, then the center drains could be placed 2x more closely than side gutters, such that the total number of storm drains per km is identical.

    IMO, flooding the sidewalk even slightly renders that facility unusable for its primary users. Whereas covering the middle of a center drained street with four inches (100 mm) of water that has a 2% cross slope (1/4-inch per ft) means that the water covers 16 ft (4.8 m) of the street, which on a typical 30 ft (9 m) residential street leaves two narrow but just usable strips on each side. Whereas on a conventional crowned street, only 3.75 inch of water would cause water on one side of the crown to spill to the other side, so 4 inches will have covered the whole street, edge to edge, impounded only by maybe the 6 inch tall curbs. I haven’t done the volumetric calculations, but I think the same curb on the center drained steet would impound much more water before encroaching in the sidewalk or adjacent properties.