Page 280 - Modern Spatiotemporal Geostatistics
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Popular  Methods  in the  Light  of  Modern  Geostatistics  261

        of such developments will be the  emergence of a powerful  computational  view-
        point in modern spatiotemporal  geostatistics that may be called  computational
        BME.  With  the  aid of  computers,  the  rigorous  mathematical  structure  of  the
        BME   model  can  distill  the  complexity  of  physical  knowledge  bases  into  hu-
        manly  manageable  amounts  of  information  in  the  form  of  space/time  maps,
        to  which  scientists  and  engineers  can apply  their  intuition  to  produce  a real-
        istic  picture  of  the  phenomenon  under  consideration.  Computational  BME  is,
        therefore,  a  theme  of  the  modern  geostatistics  paradigm  that  involves  com-
        bining  actual  observations  of  real  phenomena with  computer  simulations  of
        the  phenomena.  These  simulations  (the  computer's  way of  "experimenting")
        are,  of  course,  physical  model-based simulations  rather  than  merely  graphical
        displays of  data  or  model-free,  fuzzy-system  representations.
             Computational  BME involves a wide range of numerical techniques,  includ-
        ing deterministic  (linear  algebra, finite differences, etc.) and stochastic schemes
        of  various  forms  (Monte  Carlo,  Brownian  dynamics,  etc.).  In  the  context  of
        BME  analysis,  the  implementation  of  these techniques  has two  main goals,  to
          •  solve  integrodifferential  and integrodifference  equations  with  respect  to
            the  BME  coefficients  at  the  prior  stage, and
          •  evaluate multidimensional  integrals of functions  of the pdf at the  posterior
            stage.
        Systematic  applications  of  the  above  techniques—together  with  analytical
        methods—seek  to  incorporate  a  part  of  physical  reality  as  large  as  possible
        into  BME  mapping.  For  computational  BME,  abstraction  and  construction
        become  close  partners  in  mapping  investigations.  Because  of  its  capacity  to
        manage  large  amounts  of  knowledge  and solve large  systems of  mathematical
        equations,  computational  BME  will  divulge  new aspects of  BME  theory  and
        will  even  lead to  theoretical  improvements.

         Modern     Spatiotemporal        Geostatistics and
         CIS   Integration    Technologies

        Geostatistical  analysis and  modeling of  natural processes is not  merely an issue
        of  inserting data  bases  into  a library of  "black  box"-type  computer  programs.
        In  many  practical  applications,  a major  challenge faced  by geostatistical  prac-
        titioners  is  how  to  integrate,  rigorously  and  effectively,  two  aspects  of  the
        information  (see Fig.  12.18)  upon which  they  draw:
          (i.)  the  powerful  theoretical  tools  and  conceptual  models  (mathematical
              equations expressing physical  laws, scientific  theories, phenomenological
              relationships,  optimal  estimators,  etc.)  which  have  usually  been  devel-
              oped  for  well-defined  conceptual  environments',  and
         (ii.)  the  site-specific  details  of  the  real  environment  under  consideration;
              in  the  case  of  a  hazardous  waste  site,  e.g.,  these details  may  include
              the  specific  hydrogeological  characteristics  of  the  site  (local  drainage
              catchment  basins,  stratigraphy,  faults,  dikes,  sills,  zones  of  alteration,
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