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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...
  • 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...
  • Re: IMSYC / SOLstice Cup
    Board » General Discussion
    You find them in Homework set 5 and 6.
    ...one of the guys behind the game...
  • 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...
  • 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...
  • 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...
  • 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...
  • 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...
  • 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...
  • 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...
  • Re: Rename boat
    Board » Technical Support
    Done :-)
    ...one of the guys behind the game...

Races

Next Race: 00d 00h 00m


Current Races:

Sinbad by Balloon 2025 - Baia de l'Oiseau to Carnarvon


How ever shall I return to report with clear report to the Sultan – asked Sinbad. It must be told this island and all its fables shall be expunged from the annals of every thousand and one night. The wind howls here, and sun be none (it’s Winter, Sin, ed.) and all days from the west, but let’s launch anyway and see if we can work our SOL Balloon north as the days pass aiming for Asthralaya, where The Mahabharata tells the ancients once tested mighty weapons, about a quarter and a million qasbah away (2500nm, ed.), perhaps one month.
Race #1885
INFOby brainaid.de
SOL Balloon PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: SYC - SBB
Race starts: Jul 23rd 11:00 Registration will open soon
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Tall Ships Races 2025 - Aberdeen to Kristiansand


Welcome to the third of four virtual Tall Ships Races in European waters which are concurrently being organized in-real-life by Sail Training International . This third race is from Aberdeen in Scotland east across the North Sea to Norway’s Kristiansand; circa 330nm in Sailonline’s magnificent 90m Barque.
NOTE: Starts and Finishes in tall ships racing are always offshore to avoid conflict with shipping and shipping lanes; online and real-life may not match exactly.
Race #1925
INFO by brainaid.de
Barque 90m PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: TS - SYC
Race starts: Jul 22nd 16:00 Registration Open!
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Marstrand to Cowes 2025


We invite you to another race, which will kick off the third quarter of our ARCH series. We'll set off from Marstrand, Sweden, which, along with Skagen, Denmark, marks the line commonly recognised as the border separating the Baltic Sea from the North Sea. The 650nm route will take our Ripitide 50 across the North Sea and the English Channel to Cowes, England. Watch out for the fast ferries crossing the Channel from Calais to Dover 😊.
Race #1935
INFO from brainaid.de
Riptide 50 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking:
ARQ3 - ARCH - SUPSOL – SYC
Race starts: Jul 21st 17:00 Registration Open!
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Nantucket Sprint 2025


Welcome to Nantucket, from whence Herman Melville’s Cap’n Ahab sailed round The Horn into the northern Pacific Ocean to hunt the gray whale - whose migrations are celebrated elsewhere in SOL’s Q4 schedule - he never to return. And whaling too, as the 19th C progressed, like Ahab disappeared from Nantucket as the harbour silted up and mainland Massachusetts whaling stations benefited from rail connections. But beach life, yachting and nostalgia has rescued the island from oblivion, so to celebrate leisure, SOL gives you the Nantucket Sprint - 25nm in 29er_XX’s from Great Point to Muskeget & Tuckernuck Islands across the sound to a finish just inside the mouth of the harbour. Enjoy!
Race 1936
INFO by brainaid.de
29er_XX PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking:
SPRQ3 - SPRCH - SUPSOL – SYC
Race starts: Jul 19th 15:00 Registration Open!
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Tall Ships Races 2025 - Dunkirk to Aberdeen


Welcome to the second of four virtual Tall Ships Races in European waters which are concurrently being organized in-real-life Sail Training International . This second race is from Dunkirk in France up the North Sea to Scotland’s Aberdeen; circa 400nm in Sailonline’s magnificent 90m Barque.
NOTE: Starts and Finishes in tall ships racing are always offshore to avoid conflict with shipping and shipping lanes; online and real-life may not match exactly.
Race #1924
INFO by brainaid.de
Barque 90m PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: TS - SYC
RACE CLOSE: Tuesday,
July 22 at 2300 UTC.
Race starts: Jul 13th 16:00 Registration Closed
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Suursaari TIMED Race 2025

The first TIMED race of the northern hemisphere Summer takes us to the Gulf of Finland on a 165nm zig-zagging course beginning and ending in the seacoast village of Haukilahti and circling the island of Suursaari. It’s only appropriate that the boat for this race is Finland’s own Club Swan 50. This is a TIMEDrace so you may RE-REGISTER HEREto try again after finishing a run. You will have 13 days and 11 hours to test your skill and decision making after the race opens.
Race #1928
INFOby brainaid.de
PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking:
TRQ3 - TRCH - SUPSOL - SYC
RACE CLOSE: Saturday,
26 July at 23:00 UTC
Race starts: Jul 13th 12:00 Registration Open!
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Lake Ontario 300 Challenge 2025

Lake Ontario Offshore Racing (LOOR) welcomes Sailonline sailors (SOLers for short) to a second virtual version of a race in their annual series, the LO300. As the name implies, the LO300 is a 300nm offshore race across the length and breadth of Lake Ontario, from and back to Port Credit YC. Once again, as is our wont on Lake Ontario, a fleet of Beneteau First 36.7s is being made available to virtual racers. There is an overall prize for the SOLer who best bosses Lake Ontario over the two races hosted by Sailonline, this 300 and the Susan Hood raced back in May; so, let the competition be fierce!
Race #1931
INFOby brainaid.de
First 36.7 PARTICULARS
NAM_AWIP WX Updates:
0245 / 0845 / 1445 / 2045
Ranking: LOOR - SYC
RACE CLOSE: Wednesday,
July 23 at 2300 UTC.
Race starts: Jul 12th 15:10 Registration Open!

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Young Island to Great Nicobar 2025

The adventure continues as we launch this fifth leg of the RWW series, racing from Young Island to Great Nicobar on the edge of the Bay of Bengal. Get ready for a chilling start as we set sail on the seventh leg of the 2025 Ocean Championship Series! A 5200nm journey of endurance, strategy, and pure sailing excitement. This leg will be pursued aboard the Super Maxi 100v2, pushing sailors to their limits. Do you have what it takes to conquer the Indian Ocean? Join us and put your skills to the ultimate test!
PRIZE: SMPF
Race #1929
INFO by brainaid.de
Super Maxi 100 v2 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: OCQ3 - RWW - OCCH - SUPSOL - SYC
Race starts: Jul 07th 11:00 Registration Closed
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Go to race archive

SYC Ranking

  1. Sailonline Yacht Club Member CriticalHippo
  2. Sailonline Yacht Club Member WRmirekd
  3. Sailonline Yacht Club Member KaSToR
  4. Sailonline Yacht Club Member rafa
  5. Sailonline Yacht Club Member Kipper1258
  6. Sailonline Yacht Club Member FreyjaUSA
  7. Sailonline Yacht Club Member vida
  8. Sailonline Yacht Club Member BRENTGRAY
  9. Sailonline Yacht Club Member rumskib
  10. Sailonline Yacht Club Member Sax747

View full list

Series

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