Few-Shot Single-View 3-D Object Reconstruction with Compositional Priors

The impressive performance of deep convolutional neural networks in single-view 3D reconstruction suggests that these models perform non-trivial reasoning about the 3D structure of the output space. However, recent work has challenged this belief, showing that complex encoder-decoder architectures perform similarly to nearest-neighbor baselines or simple linear decoder models that exploit large amounts of per category data in standard benchmarks. On the other hand settings where 3D shape must be inferred for new categories with few examples are more natural and require models that generalize about shapes. In this work we demonstrate experimentally that naive baselines do not apply when the goal is to learn to reconstruct novel objects using very few examples, and that in a \emph{few-shot} learning setting, the network must learn concepts that can be applied to new categories, avoiding rote memorization. To address deficiencies in existing approaches to this problem, we propose three approaches that efficiently integrate a class prior into a 3D reconstruction model, allowing to account for intra-class variability and imposing an implicit compositional structure that the model should learn. Experiments on the popular ShapeNet database demonstrate that our method significantly outperform existing baselines on this task in the few-shot setting

Functional Maps Representation on Product Manifolds

We consider the tasks of representing, analyzing and manipulating maps between shapes. We model maps as densities over the product manifold of the input shapes; these densities can be treated as scalar functions and therefore are manipulable using the language of signal processing on manifolds. Being a manifold itself, the product space endows the set of maps with a geometry of its own, which we exploit to define map operations in the spectral domain; we also derive relationships with other existing representations (soft maps and functional maps). To apply these ideas in practice, we discretize product manifolds and their Laplace--Beltrami operators, and we introduce localized spectral analysis of the product manifold as a novel tool for map processing. Our framework applies to maps defined between and across 2D and 3D shapes without requiring special adjustment, and it can be implemented efficiently with simple operations on sparse matrices.Comment: Accepted to Computer Graphics Foru

Unfolding the Hierarchy of Voids

We present a framework for the hierarchical identification and characterization of voids based on the Watershed Void Finder. The Hierarchical Void Finder is based on a generalization of the scale space of a density field invoked in order to trace the hierarchical nature and structure of cosmological voids. At each level of the hierarchy, the watershed transform is used to identify the voids at that particular scale. By identifying the overlapping regions between watershed basins in adjacent levels, the hierarchical void tree is constructed. Applications on a hierarchical Voronoi model and on a set of cosmological simulations illustrate its potential.Comment: 5 pages, 2 figure

Activation in a Frontoparietal Cortical Network Underlies Individual Differences in the Performance of an Embedded Figures Task

The Embedded Figures Test (EFT) requires observers to search for a simple geometric shape hidden inside a more complex figure. Surprisingly, performance in the EFT is negatively correlated with susceptibility to illusions of spatial orientation, such as the Roelofs effect. Using fMRI, we previously demonstrated that regions in parietal cortex are involved in the contextual processing associated with the Roelofs task. In the present study, we found that similar parietal regions (superior parietal cortex and precuneus) were more active during the EFT than during a simple matching task. Importantly, these parietal activations overlapped with regions found to be involved during contextual processing in the Roelofs illusion. Additional parietal and frontal areas, in the right hemisphere, showed strong correlations between brain activity and behavioral performance during the search task. We propose that the posterior parietal regions are necessary for processing contextual information across many different, but related visuospatial tasks, with additional parietal and frontal regions serving to coordinate this processing in participants proficient in the task

Field independence associates with mathematics and science performance in 5- to 10-year-olds after accounting for domain-general factors

Field independence describes the extent to which individuals are influenced by context when trying to identify embedded targets. It associates with cognitive functioning and is a predictor of academic achievement. However, little is known about the neural and cognitive underpinnings of field independence which lead to these associations. Here we investigated behavioural associations between two measures of field independence (Children’s Embedded Figures Test (CEFT) and Design Organisation Test (DOT)) and performance on mathematics (reasoning and written arithmetic) and science tests (reasoning and scientific inquiry) in 135 children aged 5-10 years. There were strong associations between field independence and mathematics and science, which were largely explained by individual differences in age, IQ, and verbal working memory. However, regression analyses indicated that after controlling for these variables, the CEFT explained additional variance on the mathematical reasoning and science tests, whereas the DOT predicted unique variance on the written arithmetic test

Culture and personality revisited: Behavioral profiles and within‐person stability in interdependent (vs. independent) social orientation and holistic (vs. analytic) cognitive style

ObjectiveWe test the proposition that both social orientation and cognitive style are constructs consisting of loosely related attributes. Thus, measures of each construct should weakly correlate among themselves, forming intraindividually stable profiles across measures over time.MethodStudy 1 tested diverse samples of Americans (N = 233) and Japanese (N = 433) with a wide range of measures of social orientation and cognitive style to explore correlations among these measures in a cross‐cultural context, using demographically heterogeneous samples. Study 2 recruited a new sample of 485 Americans and Canadians and examined their profiles on measures of social orientation and cognitive style twice, one month apart, to assess the stability of individual profiles using these variables.ResultsDespite finding typical cross‐cultural differences, Study 1 demonstrated negligible correlations both among measures of social orientation and among measures of cognitive style. Study 2 demonstrated stable intraindividual behavioral profiles across measures capturing idiosyncratic patters of social orientation and cognitive style, despite negligible correlations among the same measures.ConclusionThe results provide support for the behavioral profile approach to conceptualizing social orientation and cognitive style, highlighting the need to assess intraindividual stability of psychological constructs in cross‐cultural research.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/162694/2/jopy12536_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/162694/1/jopy12536.pd

A survey of partial differential equations in geometric design

YesComputer aided geometric design is an area where the improvement of surface generation techniques is an everlasting demand since faster and more accurate geometric models are required. Traditional methods for generating surfaces were initially mainly based upon interpolation algorithms. Recently, partial differential equations (PDE) were introduced as a valuable tool for geometric modelling since they offer a number of features from which these areas can benefit. This work summarises the uses given to PDE surfaces as a surface generation technique togethe

The influence of individual cognitive style on performance in management education

This paper reports the outcomes of an empirical study undertaken to explore the possibility that cognitive style may be an important factor influencing performance on certain types of task in management education. Four hundred and twelve final-year undergraduate degree students studying management and business administration were tested using the Allinson-Hayes Cognitive Style Index. Their cognitive styles were then compared with assessment grades achieved for academic modules, the task categories of which were deemed to be consonant with either the wholist/intuitive or the analytic style of working. Overall ability defined by final degree grades was also tested against individuals’ cognitive styles. As expected, students whose dominant cognitive styles were analytic attained higher grades for long term solitary tasks involving careful planning and analysis of information. However, contrary to expectations, performance on tasks believed to be more suited to the wholist/intuitive style was also higher for analytic individuals, as was overall ability defined by final degree grades. The results were discussed in terms of the nature of the tasks and the need for methods of performance assessment that are independent of an orientation bias. Without this, it is argued, employment selection criteria may favour the wrong type of candidate in some circumstances

Effects of Cocaine-Kindling on the Expression of NMDA Receptors and Glutamate Levels in Mouse Brain

In the present study we examined the effects of cocaine seizure kindling on the expression of NMDA receptors and levels of extracellular glutamate in mouse brain. Quantitative autoradiography did not reveal any changes in binding of [3H] MK-801 to NMDA receptors in several brain regions. Likewise, in situ hybridization and Western blotting revealed no alteration in expression of the NMDA receptor subunits, NR1 and NR2B. Basal overflow of glutamate in the ventral hippocampus determined by microdialysis in freely moving animals also did not differ between cocaine-kindled and control groups. Perfusion with the selective excitatory amino acid transporter inhibitor, pyrrolidine-2,4-dicarboxylic acid (tPDC, 0.6 mM), increased glutamate overflow confirming transport inhibition. Importantly, KCl-evoked glutamate overflow under tPDC perfusion was significantly higher in cocaine-kindled mice than in control mice. These data suggest that enhancement of depolarization stimulated glutamate release may be one of the mechanisms underlying the development of increased seizure susceptibility after cocaine kindling

Counseling Update: A Flexible Monitoring Method for the Client and Practitioner

Recent years have seen a number of articles questioning both the utility and practicality of single-case designs. The authors propose a flexible monitoring method for practice evaluation. The proposed method is presented as a dynamic model, one that utilizes the existing evaluative procedures of the practitioner. This flexible method is proposed within the general outlines of developmental research. It is proposed as a method designed to lead practitioners toward an empirical model of practice. Some case examples are provided to substantiate the utility and value of the model.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68429/2/10.1177_104973159300300203.pd