/Users/andrea/_magisterarbeit/korpus/clean/trainkorpus/30/file_136.html NN ----------------------------------------- : Search NP Contact NP Information NP Program NP Registration NN Postdoc NP Membership NP Application NN Program NN Feedback NN Material NN from IN Talks NNS Audio JJ Video NP Industrial NP Programs NP Program NP Solicitation NN Talk NN abstract JJ . SENT Simulation NN of IN Incompressible JJ Flows NNS Using VVG the DT Lattice NN Boltzmann NP Method NN Viswanathan NP Babu NP , , Ford NP Scientific NP Research NP Lab NP . SENT The DT lattice NN Boltzmann NP LB NP method NN , , which WDT is VBZ closely RB related VVN to TO the DT lattice NN gas NN LG NP method NN , , will MD be VB discussed VVN in IN detail NN . SENT The DT LG NP method NN is VBZ boolean JJ in IN nature NN using VVG only JJ bits NNS to TO indicate VV the DT presence NN or CC absence NN of IN a DT particle NN moving VVG in IN a DT particular JJ direction NN and CC speed NN . SENT The DT absence NN of IN floating VVG point NN operations NNS gives VVZ the DT LG NP method NN unconditional JJ numerical JJ stability NN but CC restricts VVZ it PP to TO specialized JJ hardware NN that WDT can MD perform VV the DT Boolean JJ logical JJ operations NNS efficiently RB . SENT The DT Boolean NP character NN also RB results VVZ in IN a DT noisy JJ signal NN that WDT must MD be VB averaged VVN over IN space NN time NN for IN reliable JJ estimates NNS . SENT The DT LB NP method NN , , on IN the DT other JJ hand NN , , tracks VVZ the DT distribution NN functions NNS or CC time NN averages NNS of IN the DT particles NNS . SENT As IN a DT result NN , , floating VVG point NN numbers NNS have VHP to TO be VB used VVN and CC so RB the DT method NN is VBZ not RB boolean JJ . SENT While IN this DT makes VVZ the DT LB NP method NN susceptible JJ to TO instabilities NNS due JJ to TO accumulation NN of IN round NN off IN errors NNS , , it PP allows VVZ the DT LB NP method NN to TO use VV a DT variety NN of IN existing VVG computer NN platforms NNS . SENT The DT signal NN to TO noise NN ratio NN of IN the DT LB NP method NN is VBZ also RB significantly RB higher JJR than IN the DT LG NP method NN . SENT Both CC the DT LB NP method NN and CC the DT LG NP method NN are VBP highly RB parallel JJ . SENT In IN fact NN , , the DT LB NP method NN optimizes VVZ extremely RB well RB on IN current JJ computer NN platforms NNS as RB will MD be VB demonstrated VVN in IN this DT talk NN . SENT The DT current JJ version NN of IN the DT LB NP code NN developed VVN at IN FRL NP runs VVZ at IN speeds NNS around IN 1 CD . SENT 7 CD Gflops NP 2 CD D NP code NN and CC 2 CD . SENT 0 CD Gflops NP 3 CD D NP code NN on IN a DT 32 CD processor NN Cray NP T NN 3 CD D NP . SENT The DT 3 CD D NP code NN has VHZ super JJ linear JJ speedup NNS linear JJ being VBG the DT theoretical JJ maximum NN and CC runs VVZ at IN a DT speed NN of IN 33 CD Gflops NNS on IN a DT 512 CD processor NN T NN 3 CD D NP . SENT The DT objective NN of IN this DT talk NN is VBZ to TO demonstrate VV the DT potential NN of IN this DT method NN as IN a DT viable JJ tool NN for IN performing VVG time NN accurate JJ simulations NNS of IN incompressible JJ flows NNS . SENT To TO that DT end NN , , two CD issues NNS will MD be VB examined VVN in IN detail NN accuracy NN and CC speed NN . SENT The DT spatial JJ and CC temporal JJ accuracy NN of IN the DT LB NP method NN will MD be VB established VVN through IN suitable JJ benchmark JJ studies NNS . SENT It PP is VBZ important JJ to TO note VV here RB that IN the DT method NN is VBZ formally RB second JJ order NN accurate JJ in IN both DT space NN and CC time NN , , an DT accuracy NN that WDT exceeds VVZ that IN of IN many JJ commercial JJ codes NNS today NN . SENT The DT speed NN at IN which WDT the DT code NN runs VVZ will MD be VB demonstrated VVN through IN actual JJ production NN runs VVZ on IN the DT parallel JJ Cray NP T NN 3 CD D NP . SENT As IN an DT example NN of IN the DT phenomenal JJ performance NN of IN the DT LB NP code NN developed VVN at IN FRL NP , , consider VVP the DT following VVG fact NN . SENT Each DT processor NN on IN the DT T NN 3 CD D NP has VHZ a DT read VVN bandwidth NN from IN memory NN to TO cache NN that WDT is VBZ limited VVN to TO 320 CD Mbytes NNS sec NN , , which WDT translates VVZ to TO 40 CD Mflops NNS since IN the DT T NN 3 CD D NP is VBZ a DT 64 CD bit NN machine NN 8 CD bytes NNS word NN . SENT Codes NNS that WDT do VVP not RB have VH cache NN reuse NN will MD be VB hardware NN limited VVN to TO this DT speed NN . SENT Our PP$ code NN runs VVZ at IN a DT speed NN of IN 60 CD Mflops NNS on IN this DT processor NN through IN cache NN reuse NN and CC other JJ optimizations NNS . SENT This DT is VBZ joint JJ work NN with IN Gary NP S NP . SENT Strumolo NP . SENT Back RB to TO Workshop NN Schedule NN 1996 CD 1997 CD Mathematics NN in IN High NP Performance NP Computing NP Homepage NP About IN the DT IMA NP What's NP Happening VVG Now RB Programs NNS and CC Activities NNS Preprint NP Publications NPS Research NP Communities NNS Visitor NN and CC Local JJ Information NP Announcement NN Program NN Registration NN Program NN Feedback NN Talks NNS Directory NN Hot JJ Topics NNS Workshops NNS People NNS Site NN Map NN Search NP webmaster NP ima NP . SENT umn NN . SENT edu NP Industrial NP Programs NP Program NP Solicitation NN Postdoc NP Membership NP Application NN University NP of IN Minnesota NP Online JJ Privacy NN Statement NN Last JJ Modified VVN . SENT Thursday NP , , 29 CD Nov NP 2001 CD 08 CD . SENT 27 CD . SENT 35 CD CST NP