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Profile for jakob



Name jakob
Email Address jakob@sailport.se
AvatarUsers avatar
Posts364
Board Signature
...one of the guys behind the game...
  • 2011-06-06 06:56:28
    Re: IMSYC 2011
    Board » General Discussion
    You people are fantastic! What enthusiasm and engagement!!! I will try to get some students to this thread. :-)
    ...one of the guys behind the game...
  • 2011-05-02 06:35:10
    Re: IMSYC / SOLstice Cup
    Board » General Discussion
    You find them in Homework set 5 and 6.
    ...one of the guys behind the game...
  • 2011-05-02 06:08:28
    Re: IMSYC / SOLstice Cup
    Board » General Discussion
    ...and if you want to play around with hull shapes etc to investigate effects on CP, trim, stability etc you might want to try the msy_hydrostatics-code that I put on the same web-page. The code lets you import hull shapes and then stretch them in various ways :-)
    ...one of the guys behind the game...
  • 2011-05-01 18:35:20
    Re: IMSYC / SOLstice Cup
    Board » General Discussion
    Regarding IMSYC: If you are interested in the rule for the IMSYC race 2011 you can find it here http://www.kth.se/polopoly_fs/1.47075!IMSYC-66%20rule.pdf
    I have about ten students designing boats for the race :-))

    /Jakob
    ...one of the guys behind the game...
  • 2011-01-15 12:33:46
    Re: Leg 2 IMOCA Global
    Board » Flag Officers » Races
    Hi

    As always in SOL: Changing course, maps etc in the middle of a race is generally a bad idea. Main reasons are:
    1) the communication problem. How do we make sure that we reach all boats with the info?
    2) We have very little control over when the changes become visible in the clients. Often, a clear-cache is needed (or long time).

    I vote for not changing courses etc unless absolutely vital.

    /Jakob
    ...one of the guys behind the game...
  • 2010-12-06 19:48:24
    Re: NOAA vs SOL weather
    Board » Technical Support
    ...well you should be careful with those softwares... especially when there is a Sailplanner available for free ;-)
    ...one of the guys behind the game...
  • 2010-12-05 20:58:26
    Re: NOAA vs SOL weather
    Board » Technical Support
    Hi all,

    You are basically all correct :-) I am the first to admit that there are many ways of doing this and that we did not spend weeks of thinking when choosing algorithm - but it works. Also (Hubert) the game winds will only correspond exactly with the GFS-forecasts when the time is exactly the time of a certain forecast frame and the point of the "observation" is exactly that of a forecast nodal point. Thus, colour coding would not be of any use at all...

    Why this attention? Is it just curiosity or weather-rounting ?

    Regards
    Jakob
    ...one of the guys behind the game...
  • 2010-12-03 16:17:40
    Re: NOAA vs SOL weather
    Board » Technical Support
    Hi

    So, about the interpolation of weather in time and space :-) Maybe some out there is longing for a short one-liner as explanation but I am afraid there is a little more to it… Here is in short the steps we take to get an "observation" (as we call it) at an arbitrary time (called t) and location based on forecasts.

    1) Find the two forecast time steps (here called t1 and t2) surrounding the time t.
    2) In space we simply use linear interpolation (in the 2 dimensions lat/long) of the forecast-data in the 4 closest forecast-nodes in the grib-file. Since the forecast has separate fields, one for northerly wind and one for easily wind we need to treat these entities separately, in our case by using complex notation. We also need to do this for both frames t1 and t2 from step 1 which thus gives us a set of two complex-valued space-interpolated wind speeds, one at t1 and one at t2.
    3) Now we need to interpolate in time as smoothly as we can. We chose to do this using simple shape functions ensuring continuous wind speed and actually in our case continuous time derivatives.

    Now, there are naturally many ways of doing this. One draw-back of this kind of interpolation is that we loose energy. Imagine the situation with constant wind speed but rotating wind direction so that at t1 the wind is due easily and at t2 it is due westly. In our interpolation we would (falsely) get that the wind speed at the time (t1+t2)/2 would be zero.

    Also note that we do not always use the GFS model from NOAA. In particular around Sweden we have more detailed forecasts.

    Hope this helped a little.

    Regards
    Jakob
    ...one of the guys behind the game...
  • 2010-09-19 15:00:56
    Re: OCTOBER 2010 - draft calendar
    Board » Flag Officers » Race Calendar
    Hi.

    We all remember the Irish-rock episode. The problem that time was the unauthorized use of protected brand names. From that point in time SOL has been, and will continue to be, careful and considerate in terms of naming races. However SOL is not by any means scared of racing between locations in the geography where others, IRL or virtually, also race. Until proven wrong SOL is of the opinion that it is totally ok for anyone to race "similar time-similar route" as IRL-races. No-one has ever raised any legal aspects regarding this. However I do want to point out that if SOL administrators (Godesses etc) do not see that a certain race fits the calendar it is up to the community to argue and be sugary :-)) Happy sailing /Jakob
    ...one of the guys behind the game...
  • 2010-06-28 14:46:05
    Re: Rename boat
    Board » Technical Support
    Done :-)
    ...one of the guys behind the game...

Races

Next Race: 00d 00h 00m

Current Races:

Refeno Rally 2024


Although since 1986 this 300nm course from Recife, Brazil, to Fernando Noronha Island has been run many times IRL, we have only used this route twice in SOL. This time it will be the route of the last race in the ARCH 2024 classification.
Although the winner of the general classification can already be determined, the fight for the next places on the podium should be fierce. There are several contenders and Dofour34 have them at their disposal. Since we are starting in Vida_Maldita's home waters, he will give us a 30-minute handicap. Or maybe we should give it to him? 😊
Race #1865
INFO from brainaid.de
Dufour 34 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking:
ARQ4 - ARCH - SUPSOL - SYC
Race starts: Dec 23rd 17:00 Registration Open!
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Tristan da Cunha TIMED Race 2024

Originally designed by NZL_Scotsman, we head for the remote outpost of Tristan da Cunha where gales and storms may come and go but the sea is everlasting. This 64nm TIMED race has been raced on several occasions before, and this time we will be doing it in Rustler 36s.
RE-REGISTER HERE to race again after finishing a run
Race #1875
INFO by brainaid.de
Rustler 36 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking:
TRQ4 - TRCH - SUPSOL - SYC
REGISTRATION CLOSE: Saturday, 28 December at 22:00 UTC
RACE CLOSE: Saturday, 28 December at 23:00 UTC
Race starts: Dec 15th 12:00 Registration Open!
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The Beagle in the Azores 2024


And west the Beagle went one final time to round the Cape of Good Hope on May 31 1836. Ashore, Darwin met up with the Astronomer Royal, Herschel, who just happened to be in South Africa at the same time mapping the southern skies. After sounding out his many ideas on evolution and extinction with Herschel, the Beagle now sailed north, stopping briefly in St Helena, Ascension and Brazil, and the Cape Verdes again, to reach the Azores on September 19, 1836. Fitzroy and Darwin at this stage were in a hurry to get back to Britain, but online in 2024 we will stay a little longer to explore this final remote archipelago in our virtual Tall Ship Class B Beagle, 630nm round and about the islands, minding as always in these waters not to bump into any large cetaceans!
Race #1758
INFOby brainaid.de
Tall Ship Class B PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: SVF - SYC
RACE CLOSE: Friday,
December 27 at 2300 UTC.
Race starts: Dec 14th 13:00 Registration Closed
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Christmas(W) to Christmas(E) Island 2024

Two waypoints, start and finish, and between them 5827 NM of two oceans. Not much time if we want to sit at the Christmas Eve table. You will need to maintain an average speed of over 10 knots, so prepare your 90ft well and choose the best of the many possible routes. Hands up everyone who knew there were TWO Christmas Islands?! OK, maybe you have sailed this Sailonline course before... but it's time to get ready for the 2024 challenge of a reversed race, starting in the Indian Ocean, racing to the Christmas Island in the Pacific! It also marks the conclusion of our prestigious Ocean Race Championship 2024. Please have fun! Fair winds!
PRIZE: SMPF
Race #1868
INFO by brainaid.de
90ft Monohull PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: OCQ4 - OCCH - SUPSOL - SYC
Race starts: Dec 02nd 11:00 Registration Closed
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SYC Ranking

  1. Sailonline Yacht Club Member WRmirekd
  2. Sailonline Yacht Club Member FreyjaUSA
  3. Sailonline Yacht Club Member Vida_Maldita
  4. Sailonline Yacht Club Member CriticalHippo
  5. Sailonline Yacht Club Member rafa
  6. Sailonline Yacht Club Member Kipper1258
  7. Sailonline Yacht Club Member Satori
  8. Sailonline Yacht Club Member Sax747
  9. Sailonline Yacht Club Member CollegeFund
  10. Sailonline Yacht Club Member BRENTGRAY

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Series

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