30 research outputs found
A Product Shape Congruity Measure via Entropy in Shape Scale Space
Product shape is one of the factors that trigger preference decisions of
customers. Congruity of shape elements and deformation of shape from the
prototype are two factors that are found to influence aesthetic response, hence
preference. We propose a measure to indirectly quantify congruity of different
parts of the shape and the degree to which the parts deviate from a sphere,
i.e. our choice of the prototype, without explicitly defining parts and their
relations. The basic signals and systems concept that we use is the entropy.
Our measure attains its lowest value for a volume enclosed by a sphere. On one
hand, deformations from the prototype cause an increase in the measure. On the
other hand, as deformations create congruent parts, our measure decreases due
to the attained harmony. Our preliminary experimental results are consistent
with our expectations.Comment: Proceedings of EUSIPCO 2017 Satellite Workshops, Corresponding
Workshop: Creative Design and Advanced Manufacturing: An emerging application
area for Signals and System
A Non-structural Representation Scheme for Articulated Shapes
For representing articulated shapes, as an alternative to the structured
models based on graphs representing part hierarchy, we propose a pixel-based
distinctness measure. Its spatial distribution yields a partitioning of the
shape into a set of regions each of which is represented via size normalized
probability distribution of the distinctness. Without imposing any structural
relation among parts, pairwise shape similarity is formulated as the cost of an
optimal assignment between respective regions. The matching is performed via
Hungarian algorithm permitting some unmatched regions. The proposed similarity
measure is employed in the context of clustering a set of shapes. The
clustering results obtained on three articulated shape datasets show that our
method performs comparable to state of the art methods utilizing component
graphs or trees even though we are not explicitly modeling component relations
Collection Center Location with Equity Considerations in Reverse Logistics Networks
This is an Accepted Manuscript of an article published by Taylor & Francis in INFOR: Information Systems and Operational Research on 2014-11-01, available online: http://dx.doi.org/10.3138/infor.52.4.157In this paper, we study a collection center location problem with equity considerations within reverse logistics network design. The aim of the problem is to determine the locations and the capacities of the collection centers through the planning horizon. For each time period, the decisions to be made include the location and the capacities of the collection centers, the amounts of products to send from each generation point to each collection center, and the amounts of products to send from each collection center to each firm. The problem has three objectives. The first one is to minimize total cost, the second one is to ensure equity among different firms, and the third is to provide steady flow of products to each firm along the planning horizon. The problem is modeled as a multi-objective mixed integer programming formulation. An implementation of the problem in Turkey within the context of waste electrical and electronic equipment collection is presented. Sensitivity analyses are conducted to observe the effect of changes in the problem parameters on the solutions. The analyses include changes in the fixed costs and container capacities, changes in the amount of supply and changes in the growth rate. In addition, the solution potential of the model and value of using a multi-period model as opposed to using a static one are investigated
Screened poisson hyperfields for shape coding
We present a novel perspective on shape characterization using the screened Poisson equation. We discuss that the effect of the screening parameter is a change of measure of the underlying metric space. Screening also indicates a conditioned random walker biased by the choice of measure. A continuum of shape fields is created by varying the screening parameter or, equivalently, the bias of the random walker. In addition to creating a regional encoding of the diffusion with a different bias, we further break down the influence of boundary interactions by considering a number of independent random walks, each emanating from a certain boundary point, whose superposition yields the screened Poisson field. Probing the screened Poisson equation from these two complementary perspectives leads to a high-dimensional hyperfield: a rich characterization of the shape that encodes global, local, interior, and boundary interactions. To extract particular shape information as needed in a compact way from the hyperfield, we apply various decompositions either to unveil parts of a shape or parts of a boundary or to create consistent mappings. The latter technique involves lower-dimensional embeddings, which we call screened Poisson encoding maps (SPEM). The expressive power of the SPEM is demonstrated via illustrative experiments as well as a quantitative shape retrieval experiment over a public benchmark database on which the SPEM method shows a high-ranking performance among the existing state-of-the-art shape retrieval methods