Moving Observer Support for Databases

Linas Bukauskas

Publikation: Bog/antologi/afhandling/rapportPh.d.-afhandlingForskning

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Resumé

Interaktiv, visuel udforskning af data stiller strenge krav til database- svel som visualiseringssystemer. Systemer, der visualiserer store datamngder, har tendens til at sge at anvende meget internt lagerplads og til at gre intensiv brug af processorkraft. Eksisterende systemer baserer sig p en arkitektur med en ls kobling mellem databasesystemet og selve visualiseringen. Denne begrnser interaktionen mellem databasesystemet og visualiseringen. Det har den konsekvens, at der ofte udveksles overfldige data mellem databasesystem og visualiseringen. Denne Ph.D. afhandling prsenterer en ny, tt kobling mellem databasesystem og visualisering. Afhandlingen beskiver VR-tret, der er en videreudvikling af R-tret og som tillader effektiv udtrk af data-objekter, der er synlige relativt til en observatr. Afhandlingen beskriver ogs en skaldt Volatile Access Structure (VAST), som tillader inkrementel udtrk af data i forhold til en observatr. VAST er en struktur, som opbevarer knuder fra VR-tret i internt lager. Til sammen tillader VR-tret og VAST effektiv ekstraktion af de objekter, der bliver synlige for en observatr i takt med at observatren bevger sig rundt mellem data-objekterne. Brug af VAST resulterer i en signifikant reduktion af antallet af objekter, som m hentes fra et VR-tr, og VAST muliggr effektiv interaktion mellem databasesystem og visualisering. Afhandlingen beskiver endelig teknikker, som udvider funktionaliteten af et obser-vatr-bevidst databasesystem til ogs at omfatte udtrk af den N mest synlige objekter. Denne funktionalitet er specielt attraktiv, nr antallet af objekter, der netop er blevet synlige, er meget stort. Afhandlingen analyserer, hvordan visualisering kan optimeres, nr en observatrs vej mellem data er kendt p forhnd. Som et resultat heraf bidrager afhandlingen med skaldte load-balancing strategier for foresprgsler, som tager skridtstrrelse og strrelsen af et inkrementelt visualiseringsbidrag i betragtning. Disse strategier skaber balance mellem de foresprgsler, der udfres i databasesystemet, og de sikrer at inden objekter, der er synlige langs en vej, springes over. Alle bidrag er implementerede, og empiriske undersgelser er foretaget. En rkke eksperimenter beskriver bidragenes egenskaber med hensyn til forskellige aspekter af effektivitet.
OriginalsprogEngelsk
Udgivelses stedAalborg, Danmark
ForlagDepartment of Computer Science, Aalborg University
Antal sider138
StatusUdgivet - 2004
NavnPh.D. thesis
Nummer27
ISSN1601-0590

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Visualization
Data storage equipment
Electronic data interchange
Resource allocation
Program processors
Scalability
Experiments

Citer dette

Bukauskas, L. (2004). Moving Observer Support for Databases. Aalborg, Danmark: Department of Computer Science, Aalborg University. Ph.D. thesis, Nr. 27
Bukauskas, Linas. / Moving Observer Support for Databases. Aalborg, Danmark : Department of Computer Science, Aalborg University, 2004. 138 s. (Ph.D. thesis; Nr. 27).
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Bukauskas, L 2004, Moving Observer Support for Databases. Ph.D. thesis, nr. 27, Department of Computer Science, Aalborg University, Aalborg, Danmark.

Moving Observer Support for Databases. / Bukauskas, Linas.

Aalborg, Danmark : Department of Computer Science, Aalborg University, 2004. 138 s. (Ph.D. thesis; Nr. 27).

Publikation: Bog/antologi/afhandling/rapportPh.d.-afhandlingForskning

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Bukauskas L. Moving Observer Support for Databases. Aalborg, Danmark: Department of Computer Science, Aalborg University, 2004. 138 s. (Ph.D. thesis; Nr. 27).