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Jeff Dean
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Attended University of Washington
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Jeff Dean

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Congrats to +Ed Felten​! Ed and I overlapped in grad school, and I know he'll be great in this role!
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My gosh, hire the gadfly. I'd love to hear his views from inside the sausage factory.
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It's nice to see the BigTable system released for public use! A small group of us, including me, built the original version in 2005 to solve a number of data storage problems we were facing, and since then, it has become the main structured storage system for hundreds of projects at Google.
 
Now the decade of work we put into NoSQL is available to everyone using GCP.  One way it shows that we've been working on this longer than anyone else: 99% read latency is 6ms vs ~300ms for other systems.
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Yep
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I just discovered "lol my thesis", wherein people give a pithy, often self-deprecating one sentence summaries of their years of thesis research.

Example:
French bees stink…slighty differently on the western part of the country as compared to the eastern part

Biology, Harvard
Real title:
Insights into Origins of Insect Social Behavior:
Chemical Signatures of Sociality in Lasioglossum albipes
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"It doesn't rain much in Wyoming."
http://library.wrds.uwyo.edu/wrp/96-06/96-06.pdf
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Nice article about pricing and effectiveness of solar energy. The most striking chat is the second to last one, which shows the amazing do in price per unit energy for solar versus other energy sources.

H/t to +Jason Wold
 
We're in the middle of a revolution. Most people will only realize it when it's almost over.
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+Tadeusz Piskozub​ thanks for the pointer, though I find no evidence of it being discussed "a lot"
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These are fun.
 
Not to critique teachers or anything. It's just that these Gifs are astoundingly elegant.
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Thanks a lot, Jeff
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I've always found the SciGen prank really funny.

If you haven't tried it, visit http://pdos.csail.mit.edu/scigen/ and click "Generate" (and scroll down to look at the generated figures and graphs).
 
"Ten years ago, a few students at MIT's Computer Science and Artificial Intelligence Lab (CSAIL) had noticed such unscrupulous practices, and set out to have some mischievous fun with it. Jeremy Stribling MS '05 PhD '09, Dan Aguayo '01 MEng '02 and Max Krohn PhD '08 spent a week or two between class projects to develop "SCIgen," a program that randomly generates nonsensical computer-science papers, complete with realistic-looking graphs, figures, and citations."

Read more at: http://phys.org/news/2015-04-mit-students-world-scientific-journals.html#jCp
In recent years, the field of academic publishing has ballooned to an estimated 30,000 peer-reviewed journals churning out some 2 million articles per year. While this growth has led to more scientific scholarship, critics argue that it has also spurred increasing numbers of low-quality 'predatory publishers' ...
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P
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Jeff Dean

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Nobody eats dried pears anymore. We sure do consume a whole lot more high-fructose corn syrup (and surprisingly, lima beans), though.

H/t to +Greg Linden
 
Great data here. Very interesting how canned fruits and vegetables have faded from the US diet as it became much easier and cheaper to get fresh berries, fruit, vegetables, and tropical fruits any time of year.
We eat so many more vegetables than we used to. Also way more high-fructose corn syrup.
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Coffee consumption went down, that surprises me.
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Interesting charts about how quickly major social changes such as interracial marriage, women's suffrage, etc. in America's past came about.
 
+Yonatan Zunger almost every graph in this article is an animation, but it has a nice G+ default image. I wonder if the problem with sharing PDFs is picking the image. Shouldn't they just be a page?
As the Supreme Court considers extending same-sex marriage rights to all Americans, we look at the patterns of social change that have tranformed the nation.
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iDreams
 
push
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Jeff Dean

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I don't normally share cat gifs, but when I do, they feature ninja cat.
 
The Return Of The Ninja Cat!!  Level ~ Advance




Cat communication is the transfer of information by one or more cats that has an effect on the current or future behaviour of another animal, including humans. Cats use a range of communication modalities including visual, auditory, tactile, chemical and gustatory.

The communication modalities used by domestic cats have been affected by domestication.


Vocalizations

Cat vocalisations have been categorised according to a range of characteristics.

Schötz categorised vocalizations according to 3 mouth actions: (1) sounds produced with the mouth closed (murmurs), including the purr, the trill and the chirrup, (2) sounds produced with the mouth open and gradually closing, comprising a large variety of miaows with similar vowel patterns, and (3) sounds produced with the mouth held tensely open in the same position, often uttered in aggressive situations (growls, yowls, snarls, hisses, spits and shrieks).

Brown et al. categorised vocal responses of cats according to the behavioural context: (1) during separation of kittens from mother cats, (2) during food deprivation, (3) during pain, (4) prior to or during threat or attack behavior, as in disputes over territory or food, (5) during a painful or acutely stressful experience, as in routine prophylactic injections and (6) during kitten deprivation. Less commonly recorded calls from mature cats included purring, conspecific greeting calls or murmurs, extended vocal dialogues between cats in separate cages, “frustration” calls during training or extinction of conditioned responses.

Miller classified vocalisations into 5 categories according to the sound produced: the purr, chirr, call, meow and growl/snarl/hiss.


Purr

The purr is a continuous, soft, vibrating sound made in the throat by most species of felines. Domestic cat kittens can purr as early as two days of age. This tonal rumbling can characterize different personalities in domestic cats. Purring is often believed to indicate a positive emotional state, but cats sometimes purr when they are ill, tense, or experiencing traumatic or painful moments.

The mechanism of how cats purr is elusive. This is partly because cats do not have a unique anatomical feature that is clearly responsible for the vocalization. One hypothesis, supported by electromyographic studies, is that cats produce the purring noise by using the vocal folds and/or the muscles of the larynx to alternately dilate and constrict the glottis rapidly, causing air vibrations during inhalation and exhalation. Combined with the steady inhalation and exhalation as the cat breathes, a purring noise is produced with strong harmonics. Purring is sometimes accompanied by other sounds, though this varies between individuals. Some may only purr, while other cats include low level outbursts sometimes described as "lurps" or "yowps".

Domestic cats purr at varying frequencies. One study reported that domestic cats purr at average frequencies of 21.98 Hz in the egressive phase and 23.24 Hz in the ingressive phase with an overall mean of 22.6 Hz. Further research on purring in four domestic cats found that the fundamental frequency varied between 20.94 and 27.21 Hz for the egressive phase and between 23.0 and 26.09 Hz for the ingressive phase. There was considerable variation between the four cats in the relative amplitude, duration and frequency between egressive and ingressive phases, although this variation generally occurred within the normal range.

One study on a single cheetah (Acinonyx jubatus) showed it purred with an average frequency of 20.87 Hz (egressive phases) and 18.32 Hz (ingressive phases). A further study on four adult cheetahs found that mean frequencies were between 19.3 Hz and 20.5 Hz in ingressive phases, and between 21.9 Hz and 23.4 Hz in egressive phases. The egressive phases were longer than ingressive phases and moreover, the amplitude was greater in the egressive phases.

It was once believed that only the cats of the genus Felis could purr. However, felids of the genus Panthera (tigers, lions, jaguars and leopards) also produce sounds similar to purring, but only when exhaling. The subdivision of the Felidae into ‘purring cats’ on the one hand and ‘roaring cats ’ (i.e. non-purring) on the other, originally goes back to Owen (1834/1835) and was definitely introduced by Pocock (1916), based on a difference in hyoid anatomy. The ‘roaring cats’ (lion, Panthera leo; tiger, P. tigris; jaguar, P. onca; leopard, P. pardus) have an incompletely ossified hyoid, which according to this theory, enables them to roar but not to purr. On the other hand, the snow leopard (Uncia uncia), as the fifth felid species with an incompletely ossified hyoid, purrs (Hemmer, 1972). All remaining species of the family Felidae (‘purring cats’) have a completely ossified hyoid which enables them to purr but not to roar. However, Weissengruber et al. (2002) argued that the ability of a cat species to purr is not affected by the anatomy of its hyoid, i.e. whether it is fully ossified or has a ligamentous epihyoid, and that, based on a technical acoustic definition of roaring, the presence of this vocalization type depends on specific characteristics of the vocal folds and an elongated vocal tract, the latter rendered possible by an incompletely ossified hyoid.





Meow

The meow is one of the most widely known vocalizations of domestic kittens. It is a call apparently used to solicit attention from the mother.

Adult cats commonly vocalise with a "meow" (or "miaow") sound, which is onomatopoeic. The meow can be assertive, plaintive, friendly, bold, welcoming, attention soliciting, demanding, or complaining. It can even be silent, where the cat opens its mouth but does not vocalize. Adult cats do not usually meow to each other and so meowing to human beings is likely to be an extension of the use by kittens.








Language differences

Different languages have correspondingly different words for the "meow" sound, including miau (Belarusian, Croatian, Hungarian, Dutch, Finnish, Lithuanian, Malay, German, Polish, Russian, Portuguese, Romanian, Spanish and Ukrainian), mnau (Czech), meong (Indonesian), niau (Ukrainian), niaou (?????, Greek), miaou (French), nya (??, Japanese), miao (?, Mandarin Chinese, Italian), miav/miao or mjav/mjau (Danish, Swedish and Norwegian), mjá (Icelandic), ya-ong (??, Korean), ????? / Miya?un_ (Urdu) and meo-meo (Vietnamese). In some languages (such as Chinese ?, mao), the vocalization became the name of the animal itself.

Read more : http://en.wikipedia.org/wiki/Cat_communication

#gif #cats #animals #caturday #caturdayeveryday #caturday2014 #catsrule #catsallovertheworld #catholic #catlovers #animallovers #animalphotography #catphotography #catphotos #catpictures #catpics #lol #funny #funnypics #funnypictures #funnyphotos #funnystuff #ANNIMATEDGIFS   #trendingnow   #lolcats
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Ninja cat!
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Jeff Dean

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A nice update about our Project Loon efforts (trying to bring internet access to billions of people via high altitude weather balloons). Since the project started, the team had been working on scaling up lots of the engineering aspects of the project (length of time the balloons stay aloft, number of balloons that can be manufactured per day, number of balloons launched per day, etc.). Nice work, +Mike Cassidy​ and the rest of the Loon team!
 
When we launched Project Loon in 2013 we hoped to answer a single question - could balloons be used to connect people to the Internet? Proving that this was possible in our New Zealand launch then led the team to start asking a much larger question - how can we make this work for everyone, no matter where they are in the world? How do you manufacture enough balloons to be able to provide coverage anywhere in the world and then launch them and control them so that there is always a balloon overhead to provide connection to the user on the ground?

In this latest video Project Lead Mike Cassidy offers a glimpse behind the scenes into how the Project Loon team have been tackling the challenges involved in moving from small scale, one-off launches and tests, to the scale and automation required to make balloon-powered Internet for all a reality.
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Quite a novel concept - I am currently based in such a location where even telephone connectivity is often not available.. Good Luck!
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Okay, this is awesome. A complete transistor level simulation of the 6502 processor, done via a process that involves melting the cover of the chip with 200°F hot sulfuric acid to expose the die, taking 72 microscope images, stitching then together to make a 342Mpixel image, and then finding polygons that represent wires and transistor to then emulate the whole thing in software.

The slides from the SIGGRAPH talk are great:
http://www.visual6502.org/docs/6502_in_action_14_web.pdf
Visual Transistor-level Simulation of the 6502 CPU and other chips! Welcome to Visual6502.org! Here we'll slowly but surely present our small team's effort to preserve, study, and document historic computers. We aim to present our work in a visual, intuitive manner for education and inspiration, ...
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mos6502
 
Thanks for boosting the 6502 signal +Jeff Dean!  Circle us for a weekly post - and see our profile for a couple of years of back catalogue.  We cover 6502 from perspectives of new projects, old products, emulation and more.
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I am dizzy but quite impressed.
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просто супер
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Introduction
I build large-scale computer systems.  I joined Google in 1999 and am currently a Google Fellow working in the Systems Infrastructure Group. While at Google, I have designed and implemented large portions of the company's advertising, crawling, indexing and query serving systems, along with various pieces of the distributed computing infrastructure that sits underneath most of Google's products. At various times, I've also worked on improving search quality, statistical machine translation, and various internal software development tools, and I've had significant involvement in the engineering hiring process.

Prior to joining Google, I was at DEC/Compaq's Western Research Laboratory, where I worked on profiling tools, microprocessor architecture, and information retrieval. Prior to graduate school, I worked at the World Health Organization's Global Programme on AIDS, developing software for statistical modeling and forecasting of the HIV/AIDS pandemic.

I earned a B.S. in computer science and economics (summa cum laude) from the University of Minnesota and received a Ph.D. and a M.S. in computer science from the University of Washington. I was elected to the National Academy of Engineering in 2009, which recognized my work on "the science and engineering of large-scale distributed computer systems."

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  • University of Washington
    Computer Science
  • University of Minnesota
    Computer Science and Economics
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Jeffrey Dean
Jeff Dean's +1's are the things they like, agree with, or want to recommend.
Improving Photo Search: A Step Across the Semantic Gap
googleresearch.blogspot.com

Posted by Chuck Rosenberg, Image Search Team Last month at Google I/O, we showed a major upgrade to the photos experience: you can now easil

The Tree of Life: YHGTBFKM: Ecological Society of America letter regardi...
phylogenomics.blogspot.com

The Tree of Life. Blog of Jonathan A. Eisen, evolutionary biologist, microbiologist and genomics researcher, Open Access and Open Science ad

Google Gives Back 2011
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العربية, Български, Català, Čeština, Dansk, Deutsch, UK English, US English, Ελληνικά, Español - España, Español - Latinoamerica, suomi, Fil