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The Galaxy Fold is still extremely fragile, and Samsung knows it • The Verge
Chaim Gartenberg:
<p>Samsung’s video exhorts owners to handle their $1,000-plus phones with kid gloves. Some of Samsung’s requests are more logical: the company advises against adding any additional screen protectors (which could interfere with the folding display). Others, though, like not applying “excessive pressure” to the touchscreen when tapping it, are a bit more unusual for a phone. Samsung also cautions that the Fold isn’t water or dustproof and that the magnets that hold it shut can interfere with other magnetic products, like credit credits, hotel room keys, or medical devices.

<iframe width="560" height="315" src="https://www.youtube-nocookie.com/embed/tZBk_Hb-X0w" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>

Unfortunately, despite all those warnings, it looks like the new Fold is still almost absurdly easy to break. <a href="https://www.youtube.com/watch?v=tZBk_Hb-X0w">As JerryRigEverything shows off in a comprehensive durability test</a>, many of the issues that plagued the first attempt at the Fold are still here: the screen is still extremely soft and easy to scratch; even fingernails are capable of damaging the display. (Samsung’s warning about tapping it too hard makes more sense now.)

JerryRigEverything’s tests also found that it was far too easy for debris to make it inside the display, which is troubling. Other parts of the test were more encouraging. The Fold does hold up admirably against attempts to fold it backward, which is a testament to the level of engineering that Samsung has put into the physical hardware.</p>


"The Galaxy Fold [internal screen] has a hardness comparable to Play-doh, soggy bread or a $2,000 stick of chewing gum," says JerryRigEverything calmly. It's somewhere around 2 on the 10-denominated <a href="https://en.wikipedia.org/wiki/Mohs_scale_of_mineral_hardness">Mohs scale</a>. The outside screen (and most smartphone screens) is about 7.
samsung  foldable  hardness 
september 2019 by charlesarthur
[1812.06162] An Empirical Model of Large-Batch Training
In an increasing number of domains it has been demonstrated that deep learning models can be trained using relatively large batch sizes without sacrificing data efficiency. However the limits of this massive data parallelism seem to differ from domain to domain, ranging from batches of tens of thousands in ImageNet to batches of millions in RL agents that play the game Dota 2. To our knowledge there is limited conceptual understanding of why these limits to batch size differ or how we might choose the correct batch size in a new domain. In this paper, we demonstrate that a simple and easy-to-measure statistic called the gradient noise scale predicts the largest useful batch size across many domains and applications, including a number of supervised learning datasets (MNIST, SVHN, CIFAR-10, ImageNet, Billion Word), reinforcement learning domains (Atari and Dota), and even generative model training (autoencoders on SVHN). We find that the noise scale increases as the loss decreases over a training run and depends on the model size primarily through improved model performance. Our empirically-motivated theory also describes the tradeoff between compute-efficiency and time-efficiency, and provides a rough model of the benefits of adaptive batch-size training.
machine-learning  algorithms  fitness-landscapes  feature-construction  hardness  to-write-about 
january 2019 by Vaguery
Elise Hunchuck en Instagram: “An account of Iceland, an account of Berlin: hardness of water is the amount of calcium and magnesium in the water and is measured in units…”
"An account of Iceland, an account of Berlin: hardness of water is the amount of calcium and magnesium in the water and is measured in units of German hardness [°1dH, where 1dH = (Calcium (mg / l) x2, 497 + Magnesium (mg / l) x4, 116) / 17.9]. The scale runs from 0 and 4°dh (very soft) to 8 to 12° dh (hard) to very hard at greater than 30°dh. The water here in Berlin ranges from 14 to 25 °dH (pretty hard to hard). It is the reason that many people complain about calcified deposits anywhere water flows – from sinks to toilets to showers to espresso machines to our skin and to our hair. You might not notice it as first, but after a while, the deposits make their mark, changing composition and appearance everywhere they’re left. After spending a few weeks out of the country, and some time in Iceland, where the water’s hardness is less than 2, and in the Reykjavik area it is particularly soft between 0.2 and 0.6°dh, I noticed the difference in my skin and, especially, my hair. I washed it and let it dry, on its own, and it finally responded, unencumbered (for the first time in almost two years) by the minerals – that particular heaviness – of Berlin.

A small thing, you might think, until you recall, for example, as Heather Davis so eloquently wrote, “we become the outside through our breath, our food, and our porous skin. We are composed of what surrounds us. We have come into existence with and because of so many others, from carbon to microbes to dogs. And all these creatures and rocks and air molecules and water all exist together, with each other, for each other. To be a human means to be the land and water and air of our surroundings. We are the outside. We are our environment.” So, in a way, one could say I was, for awhile, becoming Iceland. And now, slowly but surely, coming back to Berlin."
berlin  iceland  water  hardness  2018  elisehunchuck  reykjavík  chemistry 
december 2018 by robertogreco
Moravec's paradox - Wikipedia
Moravec's paradox is the discovery by artificial intelligence and robotics researchers that, contrary to traditional assumptions, high-level reasoning requires very little computation, but low-level sensorimotor skills require enormous computational resources. The principle was articulated by Hans Moravec, Rodney Brooks, Marvin Minsky and others in the 1980s. As Moravec writes, "it is comparatively easy to make computers exhibit adult level performance on intelligence tests or playing checkers, and difficult or impossible to give them the skills of a one-year-old when it comes to perception and mobility".[1]

Similarly, Minsky emphasized that the most difficult human skills to reverse engineer are those that are unconscious. "In general, we're least aware of what our minds do best", he wrote, and added "we're more aware of simple processes that don't work well than of complex ones that work flawlessly".[2]

...

One possible explanation of the paradox, offered by Moravec, is based on evolution. All human skills are implemented biologically, using machinery designed by the process of natural selection. In the course of their evolution, natural selection has tended to preserve design improvements and optimizations. The older a skill is, the more time natural selection has had to improve the design. Abstract thought developed only very recently, and consequently, we should not expect its implementation to be particularly efficient.

As Moravec writes:

Encoded in the large, highly evolved sensory and motor portions of the human brain is a billion years of experience about the nature of the world and how to survive in it. The deliberate process we call reasoning is, I believe, the thinnest veneer of human thought, effective only because it is supported by this much older and much more powerful, though usually unconscious, sensorimotor knowledge. We are all prodigious olympians in perceptual and motor areas, so good that we make the difficult look easy. Abstract thought, though, is a new trick, perhaps less than 100 thousand years old. We have not yet mastered it. It is not all that intrinsically difficult; it just seems so when we do it.[3]

A compact way to express this argument would be:

- We should expect the difficulty of reverse-engineering any human skill to be roughly proportional to the amount of time that skill has been evolving in animals.
- The oldest human skills are largely unconscious and so appear to us to be effortless.
- Therefore, we should expect skills that appear effortless to be difficult to reverse-engineer, but skills that require effort may not necessarily be difficult to engineer at all.
concept  wiki  reference  paradox  ai  intelligence  reason  instinct  neuro  psychology  cog-psych  hardness  logic  deep-learning  time  evopsych  evolution  sapiens  the-self  EEA  embodied  embodied-cognition  abstraction  universalism-particularism  gnosis-logos  robotics 
june 2018 by nhaliday
Transformable topological mechanical metamaterials : Nature Communications
New mechanical metamaterial design, can switch edges from hard to soft by apply strain in certain ways. Applicable as an analog to shear thickening liquid armor?
mechanical  metamaterial  materials  science  research  technology  variable  hardness  soft  hard  Delicious 
january 2017 by asteroza

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