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3D Shape Searching Principal
Investigator: Afzal Godil (301) 975-4262
afzal.godil@nist.gov
Objective:
To continue work on the 3D Shape searching
technology for searching for parts across a manufacturer’s supply chain and for
retrieval and classification from a Structural Bioinformatics Database Background:
3D objects are widespread and used in many
diverse areas such as computer graphics, computer aided design, computer vision
and cultural heritage, medical imaging, structural biology, and other fields.
Large numbers of 3D models are created every day and many are stored in publicly
available databases. Understanding the 3D shape and structure of these models is
essential to many scientific activities. These 3D scientific databases require
methods for storage, indexing, searching, clustering, retrieval, and recognition
of the content under study. While there has been work done in the retrieval of
text and 2D images, these methods simply can’t be extended to 3D data. 3D search
requires surface-based and volume-based features or descriptors to effectively
characterize the shape, semantics, and geometric topology. We plan to develop 3D
shape searching technologies for: 1) for searching for CAD type parts across the
manufacturer’s supply chain; and 2) for the emerging field of structural
bioinformatics.
According to AutoDesk there are over 20 Billion CAD models, compared to 6
Billion people. Different estimates by experts put the number of unique designs
of parts at around 60 to 800 Billion. Even a single Boeing Aircraft 787 has more
than 3 million unique parts from different part suppliers. Using 3D shape
searching early in the design cycle can detect duplicate parts and can also
locate similar parts manufactured across your supply chain. Hence there will be
cost saving associated parts reuse and avoiding duplicate parts to help identify
and reuse their existing designs and manufacturing processes.
It is widely believed that the 3D shapes of macro molecules and their active
sites provide a discriminating role in bio-molecular recognition and function.
Geometrical shapes determine their ability to bind to their targets.
Characterization of geometrical shape may thus provide information to classify
and retrieve related and functionally relevant macro-molecules for purposes such
as drug targeting. There are over 46,000 protein structures in the Protein Data
Bank (PDB). These 3D structural databases pose challenges for storing, indexing,
searching, clustering, retrieval of shape based structural information.
Techniques used in text based retrieval of structural information may not be
easily extended to shape based 3D or 2D searches that require surface-based and
volume-based descriptors to effectively characterize the shape, semantics and
geometric topology. Hence there is a need for an automated rule-based 3D
retrieval and classification system to efficiently manage Structural
Bioinformatics Databases. We have developed a shape based retrieval and
classification method for a few of the structures taken from the PDB. The method
involves developing 3D shape descriptors to describe the 3D shape of each
structure. The shape descriptors that we have developed are based on histograms
of distances between atoms, moments and Spherical harmonics of the surface of
the molecules. We have used this method to develop proximity measures for
structures that may be used for assessing their similarity.
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