1,124 research outputs found
The Objective in War
In considering this subject, we must be clear about the distinction between the political objective and military objective. The two are different but not separate. For nations do not wage war for war\u27s sake, but in pursuance of policy. The military objective is only the means to a political end
Video-based online face recognition using identity surfaces
Recognising faces across multiple views is more challenging
than that from a fixed view because of the severe
non-linearity caused by rotation in depth, self-occlusion,
self-shading, and change of illumination. The problem
can be related to the problem of modelling the spatiotemporal
dynamics of moving faces from video input for
unconstrained live face recognition. Both problems remain
largely under-developed. To address the problems, a novel
approach is presented in this paper. A multi-view dynamic
face model is designed to extract the shape-and-pose-free
texture patterns of faces. The model provides a precise correspondence
to the task of recognition since the 3D shape
information is used to warp the multi-view faces onto the
model mean shape in frontal-view. The identity surface of
each subject is constructed in a discriminant feature space
from a sparse set of face texture patterns, or more practically,
from one or more learning sequences containing
the face of the subject. Instead of matching templates or
estimating multi-modal density functions, face recognition
can be performed by computing the pattern distances to the
identity surfaces or trajectory distances between the object
and model trajectories. Experimental results depict that this
approach provides an accurate recognition rate while using
trajectory distances achieves a more robust performance
since the trajectories encode the spatio-temporal information
and contain accumulated evidence about the moving
faces in a video input
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A Common Data Model for Meta-Data in Interoperable Environments
A Common Data Model is a unifying structure used to allow heterogeneous environments to interoperate. An Object Oriented common model is presented in this paper, which provides this unifying structure for a Meta-Data Repository Visualisation Tool. The creation of this common model from the Meta-Data held in component databases is described. The role this common model has in interoperable environments is discussed, and the physical architecture created from the examination of the Meta-Data in the Repository common model is described
Restricted Dislocation Motion in Crystals of Colloidal Dimer Particles
At high area fractions, monolayers of colloidal dimer particles form a
degenerate crystal (DC) structure in which the particle lobes occupy triangular
lattice sites while the particles are oriented randomly along any of the three
lattice directions. We report that dislocation glide in DCs is blocked by
certain particle orientations. The mean number of lattice constants between
such obstacles is 4.6 +/- 0.2 in experimentally observed DC grains and 6.18 +/-
0.01 in simulated monocrystalline DCs. Dislocation propagation beyond these
obstacles is observed to proceed through dislocation reactions. We estimate
that the energetic cost of dislocation pair separation via such reactions in an
otherwise defect free DC grows linearly with final separation, hinting that the
material properties of DCs may be dramatically different from those of 2-D
crystals of spheres
Constructing facial identity surfaces in a nonlinear discriminating space
Recognising face with large pose variation is more challenging than that in a fixed view, e.g. frontal-view, due to the severe non-linearity caused by rotation in depth, self-shading and self-occlusion. To address this problem, a multi-view dynamic face model is designed to extract the shape-and-pose-free facial texture patterns from multi-view face images. Kernel Discriminant Analysis is developed to extract the significant non-linear discriminating features which maximise the between-class variance and minimise the within-class variance. By using the kernel technique, this process is equivalent to a Linear Discriminant Analysis in a high-dimensional feature space which can be solved conveniently. The identity surfaces are then constructed from these non-linear discriminating features. Face recognition can be performed dynamically from an image sequence by matching an object trajectory and model trajectories on the identity surfaces
Synthesis and Assembly of Nonspherical Hollow Silica Colloids Under Confinement
Hard peanut-shaped colloids were synthesized and organized into a degenerate crystal (DC), a phase previously observed only in simulations. In this structure, particle lobes tile a triangular lattice while their orientations uniformly populate the three underlying crystalline directions
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HYDRATE CORE DRILLING TESTS
The ''Methane Hydrate Production from Alaskan Permafrost'' project is a three-year endeavor being conducted by Maurer Technology Inc. (MTI), Noble, and Anadarko Petroleum, in partnership with the U.S. DOE National Energy Technology Laboratory (NETL). The project's goal is to build on previous and ongoing R&D in the area of onshore hydrate deposition. The project team plans to design and implement a program to safely and economically drill, core and produce gas from arctic hydrates. The current work scope includes drilling and coring one well on Anadarko leases in FY 2003 during the winter drilling season. A specially built on-site core analysis laboratory will be used to determine some of the physical characteristics of the hydrates and surrounding rock. Prior to going to the field, the project team designed and conducted a controlled series of coring tests for simulating coring of hydrate formations. A variety of equipment and procedures were tested and modified to develop a practical solution for this special application. This Topical Report summarizes these coring tests. A special facility was designed and installed at MTI's Drilling Research Center (DRC) in Houston and used to conduct coring tests. Equipment and procedures were tested by cutting cores from frozen mixtures of sand and water supported by casing and designed to simulate hydrate formations. Tests were conducted with chilled drilling fluids. Tests showed that frozen core can be washed out and reduced in size by the action of the drilling fluid. Washing of the core by the drilling fluid caused a reduction in core diameter, making core recovery very difficult (if not impossible). One successful solution was to drill the last 6 inches of core dry (without fluid circulation). These tests demonstrated that it will be difficult to capture core when drilling in permafrost or hydrates without implementing certain safeguards. Among the coring tests was a simulated hydrate formation comprised of coarse, large-grain sand in ice. Results with this core showed that the viscosity of the drilling fluid must also be carefully controlled. When coarse sand was being cored, the core barrel became stuck because the drilling fluid was not viscous enough to completely remove the large grains of sand. These tests were very valuable to the project by showing the difficulties in coring permafrost or hydrates in a laboratory environment (as opposed to a field environment where drilling costs are much higher and the potential loss of equipment greater). Among the conclusions reached from these simulated hydrate coring tests are the following: Frozen hydrate core samples can be recovered successfully; A spring-finger core catcher works best for catching hydrate cores; Drilling fluid can erode the core and reduces its diameter, making it more difficult to capture the core; Mud must be designed with proper viscosity to lift larger cuttings; and The bottom 6 inches of core may need to be drilled dry to capture the core successfully
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