PrimeGrid
Please visit donation page to help the project cover running costs for this month

Toggle Menu

Join PrimeGrid

Returning Participants

Community

Leader Boards

Results

Other

drummers-lowrise

Advanced search

Message boards : General discussion : Looking for a BOINC project idea. Any help?

Author Message
Dj Ninja
Send message
Joined: 2 Jan 08
Posts: 23
ID: 17009
Credit: 385,365,738
RAC: 0
321 LLR Amethyst: Earned 1,000,000 credits (1,504,087)Cullen LLR Gold: Earned 500,000 credits (918,385)ESP LLR Gold: Earned 500,000 credits (642,222)Generalized Cullen/Woodall LLR Amethyst: Earned 1,000,000 credits (1,283,081)PPS LLR Amethyst: Earned 1,000,000 credits (1,106,763)PSP LLR Turquoise: Earned 5,000,000 credits (9,196,702)SoB LLR Gold: Earned 500,000 credits (886,368)SR5 LLR Turquoise: Earned 5,000,000 credits (5,475,368)SGS LLR Gold: Earned 500,000 credits (666,456)TPS LLR (retired) Bronze: Earned 10,000 credits (25,042)TRP LLR Ruby: Earned 2,000,000 credits (2,531,511)Cullen/Woodall Sieve (suspended) Bronze: Earned 10,000 credits (11,093)Generalized Cullen/Woodall Sieve (suspended) Turquoise: Earned 5,000,000 credits (6,455,611)PPS Sieve Double Silver: Earned 200,000,000 credits (200,683,046)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Sapphire: Earned 20,000,000 credits (20,521,791)AP 26/27 Ruby: Earned 2,000,000 credits (2,763,521)GFN Double Bronze: Earned 100,000,000 credits (130,686,306)
Message 86284 - Posted: 17 Jun 2015 | 21:43:14 UTC

I like to start an own BOINC project in order to test/train my programming abilities and maybe have some fun with BOINC. But even with all the hours of thinking about it - I don't know what to compute. A mathematical problem would be nice, but it has to be one which can be understood without being a mathematics professor. At least understood good enough to attempt finding a solution, putting a "nice try" to it and not just wasting time. Finding a big prime number is a good example, it can be understood very easy but is hard to accomplish.

Any ideas? Non-mathematical ideas?

Thanks.

HonzaProject donor
Volunteer moderator
Volunteer tester
Project scientist
Send message
Joined: 15 Aug 05
Posts: 1893
ID: 352
Credit: 3,141,484,578
RAC: 0
Discovered 7 mega primesEliminated 4 conjecture "k"sFound 2 primes in the 2018 Tour de PrimesFound 1 prime in the 2018 Tour de Primes Mountain Stage2019 Tour de Primes largest primeFound 4 primes in the 2019 Tour de PrimesFound 1 mega prime in the 2019 Tour de PrimesFound 1 prime in the 2019 Tour de Primes Mountain StageFound 1 prime in the 2020 Tour de Primes321 LLR Double Bronze: Earned 100,000,000 credits (100,425,701)Cullen LLR Emerald: Earned 50,000,000 credits (60,526,018)ESP LLR Emerald: Earned 50,000,000 credits (50,853,190)Generalized Cullen/Woodall LLR Emerald: Earned 50,000,000 credits (50,309,119)PPS LLR Double Bronze: Earned 100,000,000 credits (122,476,468)PSP LLR Emerald: Earned 50,000,000 credits (50,563,867)SoB LLR Double Bronze: Earned 100,000,000 credits (101,573,710)SR5 LLR Double Bronze: Earned 100,000,000 credits (101,883,529)SGS LLR Emerald: Earned 50,000,000 credits (55,573,529)TPS LLR (retired) Bronze: Earned 10,000 credits (43,033)TRP LLR Double Bronze: Earned 100,000,000 credits (100,338,924)Woodall LLR Emerald: Earned 50,000,000 credits (50,956,094)321 Sieve Double Bronze: Earned 100,000,000 credits (115,948,450)Cullen/Woodall Sieve (suspended) Ruby: Earned 2,000,000 credits (4,142,109)Generalized Cullen/Woodall Sieve (suspended) Emerald: Earned 50,000,000 credits (50,504,945)PPS Sieve Double Gold: Earned 500,000,000 credits (513,057,580)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Sapphire: Earned 20,000,000 credits (20,288,222)TRP Sieve (suspended) Sapphire: Earned 20,000,000 credits (20,149,354)AP 26/27 Double Silver: Earned 200,000,000 credits (232,724,773)GFN Double Gold: Earned 500,000,000 credits (764,816,358)PSA Double Gold: Earned 500,000,000 credits (535,232,795)
Message 86289 - Posted: 18 Jun 2015 | 6:26:11 UTC

Running a BOINC project is not an easy job, especially in one-man-show manner.

But if, I would start with default application to make infrastructure going.
Then thinking about resuming some of retired projects.
See there for example - http://boincstats.com/en/forum/12
____________
My stats
Badge score: 1*1 + 5*1 + 8*3 + 9*11 + 10*1 + 11*1 + 12*3 = 186

Profile mikey
Avatar
Send message
Joined: 17 Mar 09
Posts: 1241
ID: 37043
Credit: 515,585,034
RAC: 0
Discovered 1 mega prime321 LLR Ruby: Earned 2,000,000 credits (2,038,739)Cullen LLR Ruby: Earned 2,000,000 credits (2,074,615)ESP LLR Ruby: Earned 2,000,000 credits (2,013,823)Generalized Cullen/Woodall LLR Ruby: Earned 2,000,000 credits (2,142,353)PPS LLR Turquoise: Earned 5,000,000 credits (5,225,319)PSP LLR Ruby: Earned 2,000,000 credits (2,049,284)SoB LLR Ruby: Earned 2,000,000 credits (2,700,268)SR5 LLR Ruby: Earned 2,000,000 credits (2,053,250)SGS LLR Turquoise: Earned 5,000,000 credits (5,147,768)TRP LLR Ruby: Earned 2,000,000 credits (2,025,737)Woodall LLR Ruby: Earned 2,000,000 credits (2,014,811)321 Sieve Sapphire: Earned 20,000,000 credits (23,770,672)Cullen/Woodall Sieve (suspended) Gold: Earned 500,000 credits (944,431)Generalized Cullen/Woodall Sieve (suspended) Sapphire: Earned 20,000,000 credits (20,813,253)PPS Sieve Double Silver: Earned 200,000,000 credits (339,665,412)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Ruby: Earned 2,000,000 credits (2,446,797)AP 26/27 Sapphire: Earned 20,000,000 credits (33,140,471)GFN Sapphire: Earned 20,000,000 credits (41,983,025)PSA Sapphire: Earned 20,000,000 credits (20,457,430)
Message 86290 - Posted: 18 Jun 2015 | 10:03:29 UTC - in response to Message 86284.

I like to start an own BOINC project in order to test/train my programming abilities and maybe have some fun with BOINC. But even with all the hours of thinking about it - I don't know what to compute. A mathematical problem would be nice, but it has to be one which can be understood without being a mathematics professor. At least understood good enough to attempt finding a solution, putting a "nice try" to it and not just wasting time. Finding a big prime number is a good example, it can be understood very easy but is hard to accomplish.

Any ideas? Non-mathematical ideas?

Thanks.


Boinc is a data analyzing program, each project gets data from someplace and then the Boinc software and project programmers break it into pieces small enough for us crunchers to crunch. There's obviously much more to it than that, but you get the idea. So what are your hobbies or data that you have easy and legal access too? Your name is "Dj" is that because of your 'job' or your name or initials? If 'job' then perhaps you could do something about analyzing the number of songs played compared to the total number available to the 'dj' on an hourly, daily, weekly, monthly, per gig basis. What songs get played more at this type of venue as opposed to that type, how has that changed in the last 10 years, 20 years, 50 years.

JimBProject donor
Honorary cruncher
Send message
Joined: 4 Aug 11
Posts: 916
ID: 107307
Credit: 974,494,092
RAC: 0
Discovered 1 mega prime321 LLR Ruby: Earned 2,000,000 credits (2,691,081)Cullen LLR Turquoise: Earned 5,000,000 credits (5,031,868)ESP LLR Turquoise: Earned 5,000,000 credits (5,064,082)Generalized Cullen/Woodall LLR Turquoise: Earned 5,000,000 credits (5,038,750)PPS LLR Turquoise: Earned 5,000,000 credits (5,000,220)PSP LLR Turquoise: Earned 5,000,000 credits (7,674,374)SoB LLR Sapphire: Earned 20,000,000 credits (42,604,648)SR5 LLR Jade: Earned 10,000,000 credits (11,829,173)SGS LLR Ruby: Earned 2,000,000 credits (2,410,767)TRP LLR Ruby: Earned 2,000,000 credits (2,291,092)Woodall LLR Turquoise: Earned 5,000,000 credits (5,046,412)321 Sieve Jade: Earned 10,000,000 credits (10,057,614)Cullen/Woodall Sieve (suspended) Ruby: Earned 2,000,000 credits (4,002,919)Generalized Cullen/Woodall Sieve (suspended) Sapphire: Earned 20,000,000 credits (20,005,451)PPS Sieve Emerald: Earned 50,000,000 credits (52,042,965)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Ruby: Earned 2,000,000 credits (2,341,676)TRP Sieve (suspended) Ruby: Earned 2,000,000 credits (2,070,804)AP 26/27 Jade: Earned 10,000,000 credits (10,742,251)GFN Emerald: Earned 50,000,000 credits (50,000,251)PSA Double Gold: Earned 500,000,000 credits (728,547,693)
Message 86291 - Posted: 18 Jun 2015 | 11:50:53 UTC

I have to echo what Honza said - running a BOINC site, or at least running it well, is something that requires a lot of time. I had experience running another high-volume LAMP (linux, apache, MySQL, php) site for 3+ years before I joined PrimeGrid, so I was somewhat able to hit the ground running. We currently have four servers that comprise this site (we could probably do it with two if necessary) plus I have a complete working site copy on one of my home servers so that I have a place to test new code. Things like the work generators and validator have to be right the first time.

There's also the expense of the servers. PrimeGrid needs pretty high-end servers these days to be able to accommodate the volume of work done, especially during challenges. While a new project can get along with a lot less, you can expect lots of growing pains. MySQL has this way of working perfectly until suddenly it doesn't and it can be a very abrupt transition.

Having applications compiled for each of the various platforms is also non-trivial. That's overseen by other people as I have quite enough to do just with the site code. We're lucky enough to be able to use programs by others (LLR by Jean Penné, genefer by Yves Gallot, various sieving programs by others) that are written and maintained outside of PrimeGrid

Bottom line is that there are a lot of people involved in running this site, not all of whom are immediately apparent. Most users are only aware of the ones who post frequently in the forums. Not all of them have fancy titles here, but they're nonetheless all very necessary and we'd miss them if for any reason they were no longer available.

Dj Ninja
Send message
Joined: 2 Jan 08
Posts: 23
ID: 17009
Credit: 385,365,738
RAC: 0
321 LLR Amethyst: Earned 1,000,000 credits (1,504,087)Cullen LLR Gold: Earned 500,000 credits (918,385)ESP LLR Gold: Earned 500,000 credits (642,222)Generalized Cullen/Woodall LLR Amethyst: Earned 1,000,000 credits (1,283,081)PPS LLR Amethyst: Earned 1,000,000 credits (1,106,763)PSP LLR Turquoise: Earned 5,000,000 credits (9,196,702)SoB LLR Gold: Earned 500,000 credits (886,368)SR5 LLR Turquoise: Earned 5,000,000 credits (5,475,368)SGS LLR Gold: Earned 500,000 credits (666,456)TPS LLR (retired) Bronze: Earned 10,000 credits (25,042)TRP LLR Ruby: Earned 2,000,000 credits (2,531,511)Cullen/Woodall Sieve (suspended) Bronze: Earned 10,000 credits (11,093)Generalized Cullen/Woodall Sieve (suspended) Turquoise: Earned 5,000,000 credits (6,455,611)PPS Sieve Double Silver: Earned 200,000,000 credits (200,683,046)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Sapphire: Earned 20,000,000 credits (20,521,791)AP 26/27 Ruby: Earned 2,000,000 credits (2,763,521)GFN Double Bronze: Earned 100,000,000 credits (130,686,306)
Message 86295 - Posted: 18 Jun 2015 | 14:33:52 UTC

Thanks for your answers, but most things I knew already. Maybe I need to explain it a bit more.

This idea is not new, because I tried it already a few years ago. I wrote a 3x+1 application in 100 percent assembler and using SSE, which was awful fast on older machines too because of the very low memory usage. I also got basic server functions running, like a PHP based scheduler/validator and work generator. The "project" was able to generate work, send it out, recieve it back and even validated it, granted credit. I discontinued the build only due to another project started tackling the 3x+1 conjecture and I think that two projects working on the same problem are not necessary. Because of that some server sided things like much of the HTML pages where not completed.

It was real fun to build the BOINC infrastructure and getting it to run even with some test users.

The project was designed to use home based servers. I never wanted to compete with big projects like SETI, Folding or WCG. I dont' know how strong your servers are, but I think in terms of computing power, I have more. The initial tests where done using an Intel Atom N270 system which ran like idle, even with the PHP based scheduler. After completing I would have moved it to a bigger machine of course, but I think the Atom would be able to hold a small project.

On PrimeGrid there are many scheduler requests allowed to a machine in a short time, probably generating high server loads. Server load on my test project was mostly related to work unit run time and time between scheduler requests.

If the project gets such a resonance that I can't maintain it without help, I'm shure to find participants who are willing to help.

In any case I like to restart/continue this work, the only thing I need is an idea to build a new suitable science application which brings in some interesting results to the users, keeping them interested and entertained.

My nickname was created by some classmates, tampering with my martial arts skills, bodybuilding efforts and dj-ing on serveral school parties. Resistance would have proven futile and so I started to use this name in eMail adresses, message bords, I wrote it on my Unreal Tournament minigun which made a pretty good mess out of the guys came up with the name... used it for the distributed computing accounts.

Profile Michael GoetzProject donor
Volunteer moderator
Project administrator
Avatar
Send message
Joined: 21 Jan 10
Posts: 13513
ID: 53948
Credit: 236,922,854
RAC: 0
Found 5 primes in the 2021 Tour de PrimesFound 5 mega primes in the 2021 Tour de PrimesThe "Shut up already!" badge:  This loud mouth has mansplained on the forums over 10 thousand times!  Sheesh!!!Discovered the World's First GFN-19 prime!!!Discovered 6 mega primesFound 1 prime in the 2018 Tour de PrimesFound 1 prime in the 2019 Tour de PrimesFound 1 prime in the 2020 Tour de Primes321 LLR Ruby: Earned 2,000,000 credits (2,822,730)Cullen LLR Ruby: Earned 2,000,000 credits (3,624,591)ESP LLR Turquoise: Earned 5,000,000 credits (5,021,269)Generalized Cullen/Woodall LLR Ruby: Earned 2,000,000 credits (2,145,754)PPS LLR Jade: Earned 10,000,000 credits (16,008,485)PSP LLR Turquoise: Earned 5,000,000 credits (5,197,957)SoB LLR Sapphire: Earned 20,000,000 credits (34,291,181)SR5 LLR Jade: Earned 10,000,000 credits (10,007,110)SGS LLR Ruby: Earned 2,000,000 credits (3,252,256)TRP LLR Turquoise: Earned 5,000,000 credits (5,084,329)Woodall LLR Ruby: Earned 2,000,000 credits (2,911,985)321 Sieve Jade: Earned 10,000,000 credits (10,061,196)Cullen/Woodall Sieve (suspended) Ruby: Earned 2,000,000 credits (4,170,256)Generalized Cullen/Woodall Sieve (suspended) Turquoise: Earned 5,000,000 credits (5,059,304)PPS Sieve Sapphire: Earned 20,000,000 credits (22,885,121)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Amethyst: Earned 1,000,000 credits (1,035,522)TRP Sieve (suspended) Ruby: Earned 2,000,000 credits (2,051,121)AP 26/27 Jade: Earned 10,000,000 credits (10,118,303)GFN Emerald: Earned 50,000,000 credits (76,733,355)PSA Jade: Earned 10,000,000 credits (12,445,029)
Message 86296 - Posted: 18 Jun 2015 | 15:40:58 UTC

One thing nobody has mentioned is Murphy's law. When you're setting up a "proof-of-concept" system you don't have to worry about it. Once you're running "for real", data integrity and survivability becomes more important.

Most people don't think about that until AFTER they've lost everything.

Disk crashes happen. Operator errors happen. Hacking happens. Site disasters happen. While it's certainly not reasonable for you to be thinking about instantaneous failover to redundant servers, you (and all BOINC projects large and small) should be thinking about how your data will be backed up. In a disaster being down for a while is expected. Loosing all the data and vanishing forever isn't.

Most small BOINC projects don't think about that, and some have just vanished after the predictable and inevitable hardware failure. I'm embarrassed to say that PrimeGrid has lost data because of a disk failure. That should never have happened (and we've taken steps to prevent it from happening in the future.)

At a minimum, I wouldn't consider running any public server without either RAID 1 disks or daily backups to local disks or other storage, AND some type of off-site backup. Computers get stolen, homes get flooded or burnt to the ground, and so forth. While running your BOINC project might be the last thing on your mind after such a disaster, you will eventually recover and pick up with your life and you might (or might not) want to get the BOINC project working again. Without the off-site backup of the data, that would be impossible.

Fortunately, it doesn't take a lot of effort (or money) to set up a decent backup plan. Doing daily database dumps and copying the dump onto an external disk is all you need for the on-site backup, and the offsite backup can be done either by rotating those external disks out to your workplace or a relative's home, or you can get some cheap cloud storage (or a complete cloud backup.) Recovering will be a real pain (it's not nearly as easy to backup the uploaded directory, so it will be out of sync with the backup database), but you'll be able to recover and get back running.
____________
My lucky number is 75898524288+1

Dj Ninja
Send message
Joined: 2 Jan 08
Posts: 23
ID: 17009
Credit: 385,365,738
RAC: 0
321 LLR Amethyst: Earned 1,000,000 credits (1,504,087)Cullen LLR Gold: Earned 500,000 credits (918,385)ESP LLR Gold: Earned 500,000 credits (642,222)Generalized Cullen/Woodall LLR Amethyst: Earned 1,000,000 credits (1,283,081)PPS LLR Amethyst: Earned 1,000,000 credits (1,106,763)PSP LLR Turquoise: Earned 5,000,000 credits (9,196,702)SoB LLR Gold: Earned 500,000 credits (886,368)SR5 LLR Turquoise: Earned 5,000,000 credits (5,475,368)SGS LLR Gold: Earned 500,000 credits (666,456)TPS LLR (retired) Bronze: Earned 10,000 credits (25,042)TRP LLR Ruby: Earned 2,000,000 credits (2,531,511)Cullen/Woodall Sieve (suspended) Bronze: Earned 10,000 credits (11,093)Generalized Cullen/Woodall Sieve (suspended) Turquoise: Earned 5,000,000 credits (6,455,611)PPS Sieve Double Silver: Earned 200,000,000 credits (200,683,046)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Sapphire: Earned 20,000,000 credits (20,521,791)AP 26/27 Ruby: Earned 2,000,000 credits (2,763,521)GFN Double Bronze: Earned 100,000,000 credits (130,686,306)
Message 86300 - Posted: 18 Jun 2015 | 16:54:45 UTC

Data security and safety is something I care about if there actual is data, which is worth this effort. Getting some external harddisk or flash drives shouldn't be a problem.

RAID systems are protecting against physical damage like a failed harddisk drive only and preventing the server from stop working. At least two of my machines are able to run a high performance RAID-5 system if needed. Logical "damage" like a software crash or hacker-intended deletion can only be solved with backups.

When the project is running and producing really important data, I could implement a script which is saving the database changes once a day to another physical machine or some remote storage location. This depends on how the data is stored. On Primegrid for example, only the found primes and tested boundaries are important. Since important primes are found infrequently and the boundaries are only a small set of numbers, only a small amount of data gets changed in the database. If you store and backup only these changes frequently and the complete database (in which the changes are included) only once a month, you're able to get data protection with very low usage of space and you can store it likely everywhere you want.

I apologize for that, but when my house burns to the ground, gets pierced with a 10 billion ton comet or nuked to kingdom come by some crazy politicans, my BOINC project will be the last of my worries. Important data might be stored somewhere else or be public, but in such an event I have bigger problems to solve.

I read the "dead projects" list likely every month. Maybe twice. Restarting an abandoned project is difficult because you have to understand it, you need at least the science application with permission to use it and you need the results generated before the shutdown. Many projects are closed because of their work is done and can't be continued. That's an advantage of some mathematical projects which are running towards infinity.

It's really hard to find a suitable science app. Could be called "proved" as no one here has submitted an idea so far. But my hope isn't fallen yet. :)

Profile mikey
Avatar
Send message
Joined: 17 Mar 09
Posts: 1241
ID: 37043
Credit: 515,585,034
RAC: 0
Discovered 1 mega prime321 LLR Ruby: Earned 2,000,000 credits (2,038,739)Cullen LLR Ruby: Earned 2,000,000 credits (2,074,615)ESP LLR Ruby: Earned 2,000,000 credits (2,013,823)Generalized Cullen/Woodall LLR Ruby: Earned 2,000,000 credits (2,142,353)PPS LLR Turquoise: Earned 5,000,000 credits (5,225,319)PSP LLR Ruby: Earned 2,000,000 credits (2,049,284)SoB LLR Ruby: Earned 2,000,000 credits (2,700,268)SR5 LLR Ruby: Earned 2,000,000 credits (2,053,250)SGS LLR Turquoise: Earned 5,000,000 credits (5,147,768)TRP LLR Ruby: Earned 2,000,000 credits (2,025,737)Woodall LLR Ruby: Earned 2,000,000 credits (2,014,811)321 Sieve Sapphire: Earned 20,000,000 credits (23,770,672)Cullen/Woodall Sieve (suspended) Gold: Earned 500,000 credits (944,431)Generalized Cullen/Woodall Sieve (suspended) Sapphire: Earned 20,000,000 credits (20,813,253)PPS Sieve Double Silver: Earned 200,000,000 credits (339,665,412)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Ruby: Earned 2,000,000 credits (2,446,797)AP 26/27 Sapphire: Earned 20,000,000 credits (33,140,471)GFN Sapphire: Earned 20,000,000 credits (41,983,025)PSA Sapphire: Earned 20,000,000 credits (20,457,430)
Message 86308 - Posted: 19 Jun 2015 | 10:15:01 UTC - in response to Message 86296.

One thing nobody has mentioned is Murphy's law. When you're setting up a "proof-of-concept" system you don't have to worry about it. Once you're running "for real", data integrity and survivability becomes more important.

Most people don't think about that until AFTER they've lost everything.


Another thing is the power required to run a Boinc Project, Callatz just had to bring in an electrician and upgrade the whole power panel etc because of the Servers etc needed to stay up and running. That isn't cheap either!

I am NOT running a project and am spending over $500 US dollars a month just crunching! I can't imagine the cost if I had to pay for even more data throughput and more electricity. Collatz has also had MANY problems with the local cable provider not living up to their promises. Being down because the cable guy didn't show up when promised can be a real hit to your users, being down for more than week because of it can be deadly to a project! Fortunately for him he was able to put up a notice on the webpage detailing the situation.

yo2013
Send message
Joined: 3 Jul 15
Posts: 3
ID: 410908
Credit: 2,417,378
RAC: 0
Cullen LLR Silver: Earned 100,000 credits (100,689)ESP LLR Bronze: Earned 10,000 credits (37,563)PSP LLR Gold: Earned 500,000 credits (998,255)SoB LLR Amethyst: Earned 1,000,000 credits (1,057,430)SR5 LLR Bronze: Earned 10,000 credits (13,868)TRP LLR Bronze: Earned 10,000 credits (22,212)Woodall LLR Silver: Earned 100,000 credits (136,884)TRP Sieve (suspended) Bronze: Earned 10,000 credits (27,873)
Message 86550 - Posted: 4 Jul 2015 | 14:08:31 UTC - in response to Message 86300.
Last modified: 4 Jul 2015 | 14:15:35 UTC


It's really hard to find a suitable science app. Could be called "proved" as no one here has submitted an idea so far. But my hope isn't fallen yet. :)


As mikey said before, it depends on what your interests are. Do you like astronomy, biology, medicine, chemistry? We still don't know.

For mathematics, you can consult this: https://en.wikipedia.org/wiki/List_of_unsolved_problems_in_mathematics

Profile composite
Volunteer tester
Send message
Joined: 16 Feb 10
Posts: 769
ID: 55391
Credit: 696,046,522
RAC: 0
Discovered 2 mega primesFound 1 prime in the 2018 Tour de Primes321 LLR Turquoise: Earned 5,000,000 credits (5,477,467)Cullen LLR Gold: Earned 500,000 credits (776,297)ESP LLR Ruby: Earned 2,000,000 credits (3,120,351)Generalized Cullen/Woodall LLR Ruby: Earned 2,000,000 credits (2,056,207)PPS LLR Sapphire: Earned 20,000,000 credits (21,475,108)PSP LLR Turquoise: Earned 5,000,000 credits (5,027,818)SoB LLR Sapphire: Earned 20,000,000 credits (25,095,209)SR5 LLR Turquoise: Earned 5,000,000 credits (6,110,877)SGS LLR Ruby: Earned 2,000,000 credits (3,477,744)TRP LLR Turquoise: Earned 5,000,000 credits (7,025,303)Woodall LLR Amethyst: Earned 1,000,000 credits (1,693,614)321 Sieve Emerald: Earned 50,000,000 credits (50,256,050)Cullen/Woodall Sieve (suspended) Turquoise: Earned 5,000,000 credits (5,571,178)Generalized Cullen/Woodall Sieve (suspended) Emerald: Earned 50,000,000 credits (50,009,610)PPS Sieve Double Silver: Earned 200,000,000 credits (316,075,694)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Jade: Earned 10,000,000 credits (10,165,888)TRP Sieve (suspended) Sapphire: Earned 20,000,000 credits (20,071,454)AP 26/27 Turquoise: Earned 5,000,000 credits (6,616,128)GFN Emerald: Earned 50,000,000 credits (53,042,140)PSA Double Bronze: Earned 100,000,000 credits (102,762,384)
Message 86564 - Posted: 5 Jul 2015 | 16:47:05 UTC

Try finding a smaller minimal length sorting network for N >= 11 inputs. https://en.wikipedia.org/wiki/Sorting_network

Minimal depth sorting networks: fastest hardwired parallel sorting using pairwise comparisons.

Minimal length sorting networks: least amount of hardware to implement hardwired parallel sorting with pairwise comparisons.

No better sorting networks have been found since 1969 for N <= 16 inputs. There was little advance in the field for decades. Then in late 2014, minimal depth was proven for N <= 16 and minimal length was proven for N <= 10, all with the known best networks.

There is opportunity (but no guarantee) of finding a smaller minimal length network for 11 <= N <= 16 because the lower bound has not been proven with the known best networks. For N > 16, no network has yet been found that is smaller than that produced by the Bose-Nelson algorithm. http://pages.ripco.net/~jgamble/nw.html

For a recent history of the problem, read the introduction of this paper: https://arxiv.org/pdf/1310.6271v2.pdf Interestingly, their approach used an off-the-shelf SAT solver on a desktop computer to determine in less than one second what took hundreds of hours (using custom software) on a Cray-2 supercomputer in 1991 (3 weeks on a desktop computer in 2011).

Some of the commentary on algorithms can be a little funny. The paper above describes the "celebrated result" of AKS, whereas the same result is described in the end-of-chapter notes in this MIT textbook to be "a somewhat unsatisfying yes". https://mitpress.mit.edu/sites/default/files/Chapter%2027.pdf

Profile JeppeSNProject donor
Avatar
Send message
Joined: 5 Apr 14
Posts: 1378
ID: 306875
Credit: 21,623,822
RAC: 0
Found 1 prime in the 2020 Tour de Primes321 LLR Gold: Earned 500,000 credits (529,293)Cullen LLR Gold: Earned 500,000 credits (611,298)ESP LLR Silver: Earned 100,000 credits (139,922)Generalized Cullen/Woodall LLR Bronze: Earned 10,000 credits (35,236)PPS LLR Turquoise: Earned 5,000,000 credits (9,594,179)PSP LLR Silver: Earned 100,000 credits (212,242)SoB LLR Silver: Earned 100,000 credits (237,390)SR5 LLR Silver: Earned 100,000 credits (145,419)SGS LLR Silver: Earned 100,000 credits (105,212)TRP LLR Silver: Earned 100,000 credits (342,501)Woodall LLR Silver: Earned 100,000 credits (109,455)321 Sieve Silver: Earned 100,000 credits (175,037)PPS Sieve Bronze: Earned 10,000 credits (10,113)AP 26/27 Bronze: Earned 10,000 credits (12,129)GFN Amethyst: Earned 1,000,000 credits (1,674,106)PSA Turquoise: Earned 5,000,000 credits (7,614,290)
Message 86565 - Posted: 5 Jul 2015 | 21:28:23 UTC - in response to Message 86564.

Interesting, I did not know much about sorting networks.

Funny that this discipline has an AKS (Ajtai–Komlós–Szemerédi) that is unrelated to (and old than) the AKS (Agrawal–Kayal–Saxena) of primality testing.

/JeppeSN

JimBProject donor
Honorary cruncher
Send message
Joined: 4 Aug 11
Posts: 916
ID: 107307
Credit: 974,494,092
RAC: 0
Discovered 1 mega prime321 LLR Ruby: Earned 2,000,000 credits (2,691,081)Cullen LLR Turquoise: Earned 5,000,000 credits (5,031,868)ESP LLR Turquoise: Earned 5,000,000 credits (5,064,082)Generalized Cullen/Woodall LLR Turquoise: Earned 5,000,000 credits (5,038,750)PPS LLR Turquoise: Earned 5,000,000 credits (5,000,220)PSP LLR Turquoise: Earned 5,000,000 credits (7,674,374)SoB LLR Sapphire: Earned 20,000,000 credits (42,604,648)SR5 LLR Jade: Earned 10,000,000 credits (11,829,173)SGS LLR Ruby: Earned 2,000,000 credits (2,410,767)TRP LLR Ruby: Earned 2,000,000 credits (2,291,092)Woodall LLR Turquoise: Earned 5,000,000 credits (5,046,412)321 Sieve Jade: Earned 10,000,000 credits (10,057,614)Cullen/Woodall Sieve (suspended) Ruby: Earned 2,000,000 credits (4,002,919)Generalized Cullen/Woodall Sieve (suspended) Sapphire: Earned 20,000,000 credits (20,005,451)PPS Sieve Emerald: Earned 50,000,000 credits (52,042,965)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Ruby: Earned 2,000,000 credits (2,341,676)TRP Sieve (suspended) Ruby: Earned 2,000,000 credits (2,070,804)AP 26/27 Jade: Earned 10,000,000 credits (10,742,251)GFN Emerald: Earned 50,000,000 credits (50,000,251)PSA Double Gold: Earned 500,000,000 credits (728,547,693)
Message 86583 - Posted: 7 Jul 2015 | 11:47:50 UTC

How about http://xkcd.com/1546/?

Profile composite
Volunteer tester
Send message
Joined: 16 Feb 10
Posts: 769
ID: 55391
Credit: 696,046,522
RAC: 0
Discovered 2 mega primesFound 1 prime in the 2018 Tour de Primes321 LLR Turquoise: Earned 5,000,000 credits (5,477,467)Cullen LLR Gold: Earned 500,000 credits (776,297)ESP LLR Ruby: Earned 2,000,000 credits (3,120,351)Generalized Cullen/Woodall LLR Ruby: Earned 2,000,000 credits (2,056,207)PPS LLR Sapphire: Earned 20,000,000 credits (21,475,108)PSP LLR Turquoise: Earned 5,000,000 credits (5,027,818)SoB LLR Sapphire: Earned 20,000,000 credits (25,095,209)SR5 LLR Turquoise: Earned 5,000,000 credits (6,110,877)SGS LLR Ruby: Earned 2,000,000 credits (3,477,744)TRP LLR Turquoise: Earned 5,000,000 credits (7,025,303)Woodall LLR Amethyst: Earned 1,000,000 credits (1,693,614)321 Sieve Emerald: Earned 50,000,000 credits (50,256,050)Cullen/Woodall Sieve (suspended) Turquoise: Earned 5,000,000 credits (5,571,178)Generalized Cullen/Woodall Sieve (suspended) Emerald: Earned 50,000,000 credits (50,009,610)PPS Sieve Double Silver: Earned 200,000,000 credits (316,075,694)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Jade: Earned 10,000,000 credits (10,165,888)TRP Sieve (suspended) Sapphire: Earned 20,000,000 credits (20,071,454)AP 26/27 Turquoise: Earned 5,000,000 credits (6,616,128)GFN Emerald: Earned 50,000,000 credits (53,042,140)PSA Double Bronze: Earned 100,000,000 credits (102,762,384)
Message 86622 - Posted: 10 Jul 2015 | 7:10:19 UTC - in response to Message 86565.
Last modified: 10 Jul 2015 | 7:13:07 UTC

I poked at the minimal length sorting network problem on and off for 25 years, trying to randomly or systematically generate smaller networks. The current version of my software is thousands of times faster than my earlier work (not accounting for faster CPUs, which also helps), by using a LRU table to cache the zero-one tests most likely to fail a set of recent trial networks. It could be made a lot smarter using SAT solver techniques to generate a smaller set of tests that will fail sooner.

I first implemented a sorting network with a loop of comparisons like

if value[line[comparator[i],1]] > value[line[comparator[i],2]] then swap values between the lines of comparator[i].


My latest version stores a zero-one value in a word and implements comparators as a pair of "1" bits in a word, using word operations to operate on all the bits in the current zero-one value so sort the values, avoiding multiple memory accesses for array indexes. The software still loops over a list of comparators to implement a sorting network.

It might be advantageous to create a "network compiler", which translates an array describing a sorting network into a set of machine instructions that implement the sorting network.

Profile composite
Volunteer tester
Send message
Joined: 16 Feb 10
Posts: 769
ID: 55391
Credit: 696,046,522
RAC: 0
Discovered 2 mega primesFound 1 prime in the 2018 Tour de Primes321 LLR Turquoise: Earned 5,000,000 credits (5,477,467)Cullen LLR Gold: Earned 500,000 credits (776,297)ESP LLR Ruby: Earned 2,000,000 credits (3,120,351)Generalized Cullen/Woodall LLR Ruby: Earned 2,000,000 credits (2,056,207)PPS LLR Sapphire: Earned 20,000,000 credits (21,475,108)PSP LLR Turquoise: Earned 5,000,000 credits (5,027,818)SoB LLR Sapphire: Earned 20,000,000 credits (25,095,209)SR5 LLR Turquoise: Earned 5,000,000 credits (6,110,877)SGS LLR Ruby: Earned 2,000,000 credits (3,477,744)TRP LLR Turquoise: Earned 5,000,000 credits (7,025,303)Woodall LLR Amethyst: Earned 1,000,000 credits (1,693,614)321 Sieve Emerald: Earned 50,000,000 credits (50,256,050)Cullen/Woodall Sieve (suspended) Turquoise: Earned 5,000,000 credits (5,571,178)Generalized Cullen/Woodall Sieve (suspended) Emerald: Earned 50,000,000 credits (50,009,610)PPS Sieve Double Silver: Earned 200,000,000 credits (316,075,694)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Jade: Earned 10,000,000 credits (10,165,888)TRP Sieve (suspended) Sapphire: Earned 20,000,000 credits (20,071,454)AP 26/27 Turquoise: Earned 5,000,000 credits (6,616,128)GFN Emerald: Earned 50,000,000 credits (53,042,140)PSA Double Bronze: Earned 100,000,000 credits (102,762,384)
Message 86629 - Posted: 10 Jul 2015 | 13:58:09 UTC - in response to Message 86300.

Oops, correcting a mistake in the peudeocode of my last post...

if value[line[comparator[i,1]]] > value[line[comparator[i,2]]] then # swap the value on the pair of lines attached to comparator i temp = value[line[comparator[i,1]] value[line[comparator[i,1]] = value[line[comparator[i,2]] value[line[comparator[i,1]] = temp endif

The actual code for the latest (bit mask) version is
bits_t sort_network (bits_t inputs) { int i; for (i = 0; i < num_comp; i++) // process all the comparators sequentially if (!((inputs & comparator_mask[i]) ^ unordered_values[i])) // input matches bad-bit pattern ... 0 ... 1 ... inputs ^= comparator_mask[i]; // XOR the two lines to change ... 0 ... 1 ... to ... 1 ... 0 ... return inputs; }

Of course for speed that would be inline code with the loop unrolled.

For anyone ambitious, sorting network evaluation can be implemented very easily on a GPU. In fact I just thought of a faster version now that replaces the test in the loop with an oblivious conditional no-op bit mask which would work even better on a GPU because there is no branching logic, and might work better in a modern CPU too because it eliminates the control unit's conditional branching that might stall the ALU's pipeline (effectively turning the CPU into a fancy programmable gate array directly implementing part of the sorting network's comparators).

Whatever you decide to do, DJ, let us know.

Profile Roger
Volunteer developer
Volunteer tester
Avatar
Send message
Joined: 27 Nov 11
Posts: 1137
ID: 120786
Credit: 267,535,355
RAC: 0
Found 1 prime in the 2018 Tour de Primes321 LLR Ruby: Earned 2,000,000 credits (2,037,982)Cullen LLR Ruby: Earned 2,000,000 credits (2,015,907)ESP LLR Ruby: Earned 2,000,000 credits (2,232,391)Generalized Cullen/Woodall LLR Ruby: Earned 2,000,000 credits (2,088,705)PPS LLR Ruby: Earned 2,000,000 credits (2,962,062)PSP LLR Ruby: Earned 2,000,000 credits (2,539,644)SoB LLR Ruby: Earned 2,000,000 credits (2,122,524)SR5 LLR Ruby: Earned 2,000,000 credits (2,238,295)SGS LLR Ruby: Earned 2,000,000 credits (4,149,199)TRP LLR Ruby: Earned 2,000,000 credits (2,125,391)Woodall LLR Ruby: Earned 2,000,000 credits (2,037,732)321 Sieve Turquoise: Earned 5,000,000 credits (5,190,731)Cullen/Woodall Sieve (suspended) Silver: Earned 100,000 credits (207,387)Generalized Cullen/Woodall Sieve (suspended) Turquoise: Earned 5,000,000 credits (5,049,697)PPS Sieve Double Bronze: Earned 100,000,000 credits (100,422,123)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Ruby: Earned 2,000,000 credits (3,227,972)TRP Sieve (suspended) Turquoise: Earned 5,000,000 credits (5,021,659)AP 26/27 Sapphire: Earned 20,000,000 credits (20,651,644)GFN Emerald: Earned 50,000,000 credits (57,918,585)PSA Sapphire: Earned 20,000,000 credits (43,298,465)
Message 86631 - Posted: 10 Jul 2015 | 14:56:17 UTC

I went to a talk recently by a Masters student project to take photos at different angles, and through intense computation come up with a 3D model of the subject.
Advantage is that cameras are relatively cheap. Subject can be very interesting, buildings, dive wrecks, etc. Scientific payoff can be large, applications in space etc.
Depends on the kind of project your looking for, but this one could be fun:
http://www.walis.wa.gov.au/forum/presentations/day-two/slides/3d-modelling-of-underwater-objects-using-photogrammetry-petra-helmholz
Other research groups around the world are also working on this. I think its begging for a Distrubted computing platform.

Profile sergeProject donor
Avatar
Send message
Joined: 21 Jun 12
Posts: 112
ID: 144858
Credit: 237,968,345
RAC: 0
Eliminated 2 conjecture "k"s321 LLR Turquoise: Earned 5,000,000 credits (5,342,838)Cullen LLR Silver: Earned 100,000 credits (158,983)ESP LLR Gold: Earned 500,000 credits (505,527)Generalized Cullen/Woodall LLR Ruby: Earned 2,000,000 credits (2,268,642)PPS LLR Sapphire: Earned 20,000,000 credits (39,140,538)PSP LLR Silver: Earned 100,000 credits (120,541)SoB LLR Amethyst: Earned 1,000,000 credits (1,280,028)SR5 LLR Ruby: Earned 2,000,000 credits (2,649,390)SGS LLR Gold: Earned 500,000 credits (518,356)TRP LLR Silver: Earned 100,000 credits (141,131)Woodall LLR Silver: Earned 100,000 credits (116,405)Cullen/Woodall Sieve (suspended) Silver: Earned 100,000 credits (235,088)PPS Sieve Amethyst: Earned 1,000,000 credits (1,031,526)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Gold: Earned 500,000 credits (500,445)TRP Sieve (suspended) Gold: Earned 500,000 credits (507,938)AP 26/27 Amethyst: Earned 1,000,000 credits (1,386,749)GFN Double Bronze: Earned 100,000,000 credits (180,408,687)PSA Silver: Earned 100,000 credits (291,533)
Message 86633 - Posted: 10 Jul 2015 | 19:29:30 UTC - in response to Message 86631.

...Or this: Time-lapse Mining from Internet Photos [SIGGRAPH 2015]

Profile mikey
Avatar
Send message
Joined: 17 Mar 09
Posts: 1241
ID: 37043
Credit: 515,585,034
RAC: 0
Discovered 1 mega prime321 LLR Ruby: Earned 2,000,000 credits (2,038,739)Cullen LLR Ruby: Earned 2,000,000 credits (2,074,615)ESP LLR Ruby: Earned 2,000,000 credits (2,013,823)Generalized Cullen/Woodall LLR Ruby: Earned 2,000,000 credits (2,142,353)PPS LLR Turquoise: Earned 5,000,000 credits (5,225,319)PSP LLR Ruby: Earned 2,000,000 credits (2,049,284)SoB LLR Ruby: Earned 2,000,000 credits (2,700,268)SR5 LLR Ruby: Earned 2,000,000 credits (2,053,250)SGS LLR Turquoise: Earned 5,000,000 credits (5,147,768)TRP LLR Ruby: Earned 2,000,000 credits (2,025,737)Woodall LLR Ruby: Earned 2,000,000 credits (2,014,811)321 Sieve Sapphire: Earned 20,000,000 credits (23,770,672)Cullen/Woodall Sieve (suspended) Gold: Earned 500,000 credits (944,431)Generalized Cullen/Woodall Sieve (suspended) Sapphire: Earned 20,000,000 credits (20,813,253)PPS Sieve Double Silver: Earned 200,000,000 credits (339,665,412)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Ruby: Earned 2,000,000 credits (2,446,797)AP 26/27 Sapphire: Earned 20,000,000 credits (33,140,471)GFN Sapphire: Earned 20,000,000 credits (41,983,025)PSA Sapphire: Earned 20,000,000 credits (20,457,430)
Message 86640 - Posted: 11 Jul 2015 | 10:30:14 UTC - in response to Message 86633.

...Or this: Time-lapse Mining from Internet Photos [SIGGRAPH 2015]


Now that's cool!

Profile composite
Volunteer tester
Send message
Joined: 16 Feb 10
Posts: 769
ID: 55391
Credit: 696,046,522
RAC: 0
Discovered 2 mega primesFound 1 prime in the 2018 Tour de Primes321 LLR Turquoise: Earned 5,000,000 credits (5,477,467)Cullen LLR Gold: Earned 500,000 credits (776,297)ESP LLR Ruby: Earned 2,000,000 credits (3,120,351)Generalized Cullen/Woodall LLR Ruby: Earned 2,000,000 credits (2,056,207)PPS LLR Sapphire: Earned 20,000,000 credits (21,475,108)PSP LLR Turquoise: Earned 5,000,000 credits (5,027,818)SoB LLR Sapphire: Earned 20,000,000 credits (25,095,209)SR5 LLR Turquoise: Earned 5,000,000 credits (6,110,877)SGS LLR Ruby: Earned 2,000,000 credits (3,477,744)TRP LLR Turquoise: Earned 5,000,000 credits (7,025,303)Woodall LLR Amethyst: Earned 1,000,000 credits (1,693,614)321 Sieve Emerald: Earned 50,000,000 credits (50,256,050)Cullen/Woodall Sieve (suspended) Turquoise: Earned 5,000,000 credits (5,571,178)Generalized Cullen/Woodall Sieve (suspended) Emerald: Earned 50,000,000 credits (50,009,610)PPS Sieve Double Silver: Earned 200,000,000 credits (316,075,694)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Jade: Earned 10,000,000 credits (10,165,888)TRP Sieve (suspended) Sapphire: Earned 20,000,000 credits (20,071,454)AP 26/27 Turquoise: Earned 5,000,000 credits (6,616,128)GFN Emerald: Earned 50,000,000 credits (53,042,140)PSA Double Bronze: Earned 100,000,000 credits (102,762,384)
Message 86642 - Posted: 11 Jul 2015 | 14:26:24 UTC - in response to Message 86631.

I went to a talk recently by a Masters student project to take photos at different angles, and through intense computation come up with a 3D model of the subject.
Advantage is that cameras are relatively cheap. Subject can be very interesting, buildings, dive wrecks, etc. Scientific payoff can be large, applications in space etc.
Depends on the kind of project your looking for, but this one could be fun:
http://www.walis.wa.gov.au/forum/presentations/day-two/slides/3d-modelling-of-underwater-objects-using-photogrammetry-petra-helmholz
Other research groups around the world are also working on this. I think its begging for a Distrubted computing platform.


Distributed computing is not needed, a laptop is fast enough. And a research topic? It's too late, gentlemen, the future has arrived.

My dentist used a camera in my mouth to make a 3-D model for a replacement tooth. The model can go to a 3-D printer to make a temporary replacement tooth (but that takes too long - the client is waiting in the chair, so he still makes the mold manually), and the permanent replacement tooth was made on a milling machine from the 3-D model for insertion on the next visit.

The camera resembles a gun with a square barrel, the end of which goes into your mouth and takes about 3000 pictures per second. The camera operator moves the device around at different angles, and a laptop computer dynamically builds a 3-D model in pieces and displays it on the screen. The laptop beeps as each large chunk of image is filled in. The camera's removable endpiece contains a 45-degree mirror which is put on in different rotations so that the operator doesn't need to do contortions to scan different areas of the mouth.

The scanning process takes a few minutes for one side of the mouth, but the camera needs to warm up for 5 minutes before starting (I don't know why). When scanning is complete, the 3-D model can be rotated by hand on the laptop's touchscreen and false-coloured by the software to highlight different areas (teeth, fillings, gums). Here's the equipment http://www.3shape.com/our-products.aspx

I'm guessing the software finds common waypoints in the images and fits cubic (or higher order) splines to them to create a 3-D model by regression analysis https://en.wikipedia.org/wiki/Regression_analysis. The math is well understood.

Profile composite
Volunteer tester
Send message
Joined: 16 Feb 10
Posts: 769
ID: 55391
Credit: 696,046,522
RAC: 0
Discovered 2 mega primesFound 1 prime in the 2018 Tour de Primes321 LLR Turquoise: Earned 5,000,000 credits (5,477,467)Cullen LLR Gold: Earned 500,000 credits (776,297)ESP LLR Ruby: Earned 2,000,000 credits (3,120,351)Generalized Cullen/Woodall LLR Ruby: Earned 2,000,000 credits (2,056,207)PPS LLR Sapphire: Earned 20,000,000 credits (21,475,108)PSP LLR Turquoise: Earned 5,000,000 credits (5,027,818)SoB LLR Sapphire: Earned 20,000,000 credits (25,095,209)SR5 LLR Turquoise: Earned 5,000,000 credits (6,110,877)SGS LLR Ruby: Earned 2,000,000 credits (3,477,744)TRP LLR Turquoise: Earned 5,000,000 credits (7,025,303)Woodall LLR Amethyst: Earned 1,000,000 credits (1,693,614)321 Sieve Emerald: Earned 50,000,000 credits (50,256,050)Cullen/Woodall Sieve (suspended) Turquoise: Earned 5,000,000 credits (5,571,178)Generalized Cullen/Woodall Sieve (suspended) Emerald: Earned 50,000,000 credits (50,009,610)PPS Sieve Double Silver: Earned 200,000,000 credits (316,075,694)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Jade: Earned 10,000,000 credits (10,165,888)TRP Sieve (suspended) Sapphire: Earned 20,000,000 credits (20,071,454)AP 26/27 Turquoise: Earned 5,000,000 credits (6,616,128)GFN Emerald: Earned 50,000,000 credits (53,042,140)PSA Double Bronze: Earned 100,000,000 credits (102,762,384)
Message 86657 - Posted: 12 Jul 2015 | 7:25:03 UTC
Last modified: 12 Jul 2015 | 7:52:03 UTC

Hey, check this out https://www.kent.edu/sites/default/files/TR-KSU-CS-2008-05.pdf Batcher is still at it more than 60 years after his early publications. It looks like the *faster* sorting network problem is of greater practical interest. The SortNet software Batcher developed might be available for use in a distributed project. See http://www.tower.com/finding-faster-sorting-networks-using-sortnet-sherenaz-al-haj-baddar-paperback/wapi/114118823 and https://www.kent.edu/sites/default/files/TR-KSU-CS-2007-06.pdf

Batcher's definition of a supercomputer is pretty funny. https://en.wikipedia.org/wiki/Ken_Batcher

This presentation https://hoytech.github.io/sorting-networks/ also talks about practical uses of sorting networks (ie. use of sorting in cryptography where information should not be leaked by a side channel, like runtime).

Maybe I'll back off prime searching and set my CPU back to hunting for sorting networks.

Message boards : General discussion : Looking for a BOINC project idea. Any help?

[Return to PrimeGrid main page]
DNS Powered by DNSEXIT.COM
Copyright © 2005 - 2022 Rytis Slatkevičius (contact) and PrimeGrid community. Server load 0.00, 0.02, 0.00
Generated 6 Jul 2022 | 10:42:50 UTC