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dissertation 100%

  Modelling the flight of starlings  By  Simon Byford ‐ sjb17u@cs.nott.ac.uk  Supervised by  Dr. Jason Atkin ‐ jaa@cs.nott.ac.uk      School of Computer Science  University of Nottingham      Submitted May 2011, in partial fulfilment of the conditions of the award of the degree:  BSc (Hons) Mathematics and Computer Science  I hereby declare that this dissertation is all my own work, except as indicated in the text  Signature:      May 6th, 2011  Abstract    A  project  was  undertaken  to  build  a  software  model  capable  of  accurately  simulating  the flocking behaviour of starlings. After reviewing the relevant literature and studying  the mechanics of flocking, such a model was carefully designed and implemented in the  Java  programming  language.  The  model  is  capable  of  exhibiting  a  range  of  flocking  behaviours  with  simulations  comprising  upwards  of  200  individual  birds.  A  great  number of behavioural parameters are available to edit before and during simulations,  where  their  effects  can  be  viewed  in  real  time.  The  ability  to  spawn  virtual  falcons  as  well as starlings introduces the notion of a predator which is an area largely unexplored  in  previous  models.  A  number  of  interesting  observations  were  made  during  the  analysis phase of this project, including the fact that simulations employing metric and  topological distances induce much the same flocking behaviour, and that the application  can  typically  handle  simulations  comprising  up  to  500  individual  birds  before  experiencing  significant  drops  in  performance.  In  summary,  the  project  was  deemed  highly successful and a number of possible future extensions were proposed.    1      Table of contents  Abstract ................................................................................................................................................... 1  1 ‐ Introduction and motivation .............................................................................................................. 5  1.1 ‐ Aims and objectives .................................................................................................................... 5  1.2 ‐ Motivation .................................................................................................................................. 6  2 ‐ Related work ...................................................................................................................................... 7  2.1 ‐ Literature .................................................................................................................................... 7  2.1.1 ‐ Flocks, Herds, and Schools: A Distributed Behavioral Model .............................................. 7  2.1.2 ‐ An empirical study of large, naturally occurring starling flocks: a benchmark in collective  animal behaviour ............................................................................................................................ 8  2.1.3 ‐ Self‐organised complex aerial displays of thousands of starlings: a model ........................ 8  2.1.4 ‐ Interaction ruling animal collective behavior depends on topological rather than metric  distance: Evidence from a field study ............................................................................................. 9  2.1.5 ‐ Steering Behaviors for Autonomous Characters ................................................................. 9  2.1.6 ‐ An efficient algorithm to find k‐nearest neighbours in flocking behaviour ....................... 10  2.1.7 ‐ Aerial flocking patterns of wintering starlings, Sturnus vulgaris, under different predation  risk ................................................................................................................................................. 10  2.1.8 ‐ Parallel Bird Flocking Simulation ........................................................................................ 10  2.1.9 ‐ Simulating and Visualizing Natural Flocking Behaviour ..................................................... 11  2.1.10 ‐ Less related work ............................................................................................................. 11  2.2 ‐ Models ...................................................................................................................................... 12  2.2.1 ‐ Boids model ....................................................................................................................... 12  2.2.2 ‐ NetLogo Flocking model .................................................................................................... 13  2.2.3 ‐ 3D Flocking Boids II ............................................................................................................ 14  2.3 ‐ Other sources ............................................................................................................................ 14  3 ‐ Some theory ..................................................................................................................................... 15  3.1 ‐ The three urges ......................................................................................................................... 15  3.1.1 ‐ Separation .......................................................................................................................... 15  3.1.2 ‐ Alignment ........................................................................................................................... 15  3.1.3 ‐ Cohesion ............................................................................................................................ 15  3.2 ‐ Additional urges ........................................................................................................................ 16  3.2.1 ‐ Predator avoidance ............................................................................................................ 16  3.2.2 ‐ Randomness ....................................................................................................................... 16  3.2.3 ‐ Migration and obstacle avoidance ..................................................................................... 16  3.3 ‐ Combining urges ....................................................................................................................... 17  2    3.4 ‐ Steering processing chains ........................................................................................................ 18  3.4.1 ‐ Falcons ............................................................................................................................... 19  3.4.2 ‐ Starlings .............................................................................................................................. 20  3.5 ‐ Metric vs topological distance .................................................................................................. 21  4 ‐ Description of the work ................................................................................................................... 23  5 ‐ Design............................................................................................................................................... 26  5.1 ‐ Language, libraries and platform .............................................................................................. 26  5.2 ‐ Prototyping ............................................................................................................................... 27  5.3 ‐ GUI Design................................................................................................................................. 28  5.4 ‐ Class diagram ............................................................................................................................ 31  6 ‐ Implementation ............................................................................................................................... 32  6.1 ‐ Design changes ......................................................................................................................... 32  6.1.1 ‐ Awareness circle ................................................................................................................ 32  6.1.2 ‐ Save/load functionality ...................................................................................................... 33  6.1.3 ‐ Removal of viewing angle attribute ................................................................................... 33  6.1.4 ‐ Anti‐aliasing ....................................................................................................................... 33  6.1.5 ‐ FPS counter ........................................................................................................................ 34  6.1.6 ‐ Sizable window .................................................................................................................. 34  6.2 ‐ Classes ....................................................................................................................................... 35  6.2.1 ‐ AwarenessCircle ................................................................................................................. 35  6.2.2 ‐ Bird ..................................................................................................................................... 35  6.2.3 ‐ DynamicSimProperties ....................................................................................................... 36  6.2.4 ‐ FPSCounter......................................................................................................................... 36  6.2.5 ‐ Falcon ................................................................................................................................. 37  6.2.6 ‐ FlockManager .................................................................................................................... 38  6.2.7 ‐ GUIPanel ............................................................................................................................ 41  6.2.8‐ SimDims .............................................................................................................................. 42  6.2.9‐ SimulationManager ............................................................................................................ 42  6.2.10 ‐ SimulationPanel ............................................................................................................... 43  6.2.11 ‐ Starling ............................................................................................................................. 43  6.2.12 ‐ StaticSimProperties .......................................................................................................... 44  6.2.13 ‐ Window ............................................................................................................................ 44  6.3 ‐ Algorithms of interest ............................................................................................................... 46  6.3.1 ‐ Calculating the distance between birds ............................................................................. 46  3    6.3.2 ‐ Calculating the average bearing ........................................................................................ 47  6.3.3 ‐ Calculating the nearest n birds (topological distance) ...................................................... 49  6.3.4 ‐ Drawing the "awareness circle" ......................................................................................... 50  6.4 ‐ Notable problems faced ........................................................................................................... 51  6.4.1 ‐ Bias towards flocking in one particular direction .............................................................. 51  6.5 ‐ Testing ....................................................................................................................................... 52  6.5.1 ‐ “Continuous testing”.......................................................................................................... 52  6.5.2 ‐ Unit testing ........................................................................................................................ 52  7 ‐ Analysis and evaluation ................................................................................................................... 53  7.1 ‐ Analysis ..................................................................................................................................... 53  7.1.1 ‐ Tests involving starlings ..................................................................................................... 53  7.1.2 ‐ Tests involving starlings and falcons .................................................................................. 62  7.1.3 ‐ Metric vs topological distance ........................................................................................... 67  7.1.4 ‐ Performance testing .......................................................................................................... 68  7.2 ‐ Evaluation ................................................................................................................................. 70  8 ‐ Summary and further work .............................................................................................................. 74  8.1 ‐ Summary ................................................................................................................................... 74  8.2 ‐ Further work ............................................................................................................................. 75  8.2.1 ‐ 3D modelling ...................................................................................................................... 75  8.2.2 ‐ Obstacles ............................................................................................................................ 75  8.2.3 ‐ Walls................................................................................................................................... 75  8.2.4 ‐ More intelligent steering algorithms ................................................................................. 75  8.2.5 ‐ Larger scenes ..................................................................................................................... 76  8.2.6 ‐ Viewing angle attribute ..................................................................................................... 76  8.2.7 ‐ Collision penalty ................................................................................................................. 76  8.2.8 ‐ Wind ................................................................................................................................... 76  8.2.9 ‐ Separate behavioural attributes for falcons and starlings................................................. 77  8.2.10 ‐ Killing and evolution modelling ....................................................................................... 77  8.2.11 ‐ Variable speeds ................................................................................................................ 77  8.2.12 ‐ Migration urge ................................................................................................................. 78  8.2.13 ‐ Custom initial bird placement .......................................................................................... 78  8.2.14 ‐ Algorithmic optimisations ................................................................................................ 78  Appendix A – Related work ................................................................................................................... 79  Bibliography .......................................................................................................................................... 80  4   

https://www.pdf-archive.com/2011/05/07/dissertation/

07/05/2011 www.pdf-archive.com

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TRUCKLOAD 1 sale HURRY! Sale prices available through Sept.

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22/07/2015 www.pdf-archive.com

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https://www.pdf-archive.com/2017/08/04/w-e-18840700/

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TTT5 Part 2 77%

The problem with this option, which can work initially, is that as the flocking compacts and beds down (after all, it’s a bag of wool!) more flock is then required to keep the saddle off the wither and from lifting at the back and tipping the rider forward out of balance.

https://www.pdf-archive.com/2014/01/17/ttt5-part-2/

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Hello egg lovers! Greetings from Pie Ranch.

https://www.pdf-archive.com/2011/10/06/october-egg-share-update/

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Placement print for Tees - by Crystal 61%

CRYSTAL CHUNG | PRINT DESIGNS ( PLACEMENT) CRYSTAL CHUNG | PRINT DESIGNS ( PLACEMENT) BLOCK A GRAPHIC EFFECT densely embroidered outline over tatami embroidered background REGULAR BLOCK Flocking CRYSTAL CHUNG | PRINT DESIGNS ( PLACEMENT) BLOCK C 8” 8” GRAPHIC EFFECT densely embroidered (密針車花) outline over veece Digital print image on densely embroidered(密針車花) densely embroidered poly jersey fabric - same outline over less dense embroi- (密針車花) outline quality as FA15 digial dered(Tatami 車花) background print fabric.

https://www.pdf-archive.com/2017/02/23/placement-print-for-tees-by-crystal/

23/02/2017 www.pdf-archive.com