Template Adaptation for Face Verification and Identification

Face recognition performance evaluation has traditionally focused on one-to-one verification, popularized by the Labeled Faces in the Wild dataset for imagery and the YouTubeFaces dataset for videos. In contrast, the newly released IJB-A face recognition dataset unifies evaluation of one-to-many face identification with one-to-one face verification over templates, or sets of imagery and videos for a subject. In this paper, we study the problem of template adaptation, a form of transfer learning to the set of media in a template. Extensive performance evaluations on IJB-A show a surprising result, that perhaps the simplest method of template adaptation, combining deep convolutional network features with template specific linear SVMs, outperforms the state-of-the-art by a wide margin. We study the effects of template size, negative set construction and classifier fusion on performance, then compare template adaptation to convolutional networks with metric learning, 2D and 3D alignment. Our unexpected conclusion is that these other methods, when combined with template adaptation, all achieve nearly the same top performance on IJB-A for template-based face verification and identification

Accelerated hardware video object segmentation: From foreground detection to connected components labelling

This is the preprint version of the Article - Copyright @ 2010 ElsevierThis paper demonstrates the use of a single-chip FPGA for the segmentation of moving objects in a video sequence. The system maintains highly accurate background models, and integrates the detection of foreground pixels with the labelling of objects using a connected components algorithm. The background models are based on 24-bit RGB values and 8-bit gray scale intensity values. A multimodal background differencing algorithm is presented, using a single FPGA chip and four blocks of RAM. The real-time connected component labelling algorithm, also designed for FPGA implementation, run-length encodes the output of the background subtraction, and performs connected component analysis on this representation. The run-length encoding, together with other parts of the algorithm, is performed in parallel; sequential operations are minimized as the number of run-lengths are typically less than the number of pixels. The two algorithms are pipelined together for maximum efficiency

Twin Ice Cores from Greenland Reveal History of Climate Change, More

Two projects conducted from 1989 to 1993 collected parallel ice cores—just 30 km apart— from the central part of the Greenland ice sheet. Each core is more than 3 km deep and extends back 110,000 years. In short, the ice cores tell a clear story: humans came of age agriculturally and industrially during the most stable climatic regime recorded in the cores. Change—large, rapid, and global—is more characteristic of the Earth\u27s climate than is stasis

Modeling Thermal Fluctuations: Phase Mixing and Percolation

We consider the nonequilibrium dynamics of a a real scalar field in a degenerate double-well potential. The system is prepared in the lowest free energy state in one of the wells and the dynamics is driven by the coupling of the field to a thermal bath. Using a simple analytical model, based on the subcritical bubbles method, we compute the fraction of the total volume which fluctuates to the opposite phase as a function of the parameters of the potential. Furthermore, we show how complete phase mixing, {\em i.e.} symmetry restoration, is related to percolation, which is dynamically driven by domain instability. Our method describes quantitatively recent results obtained by numerical simulations, and is applicable to systems in the Ising universality class.Comment: Latex, 7 pages, 2 postscript figures, submitted to PRL. Also available at http://fnas08.fnal.gov

Thresholds for topological codes in the presence of loss

Many proposals for quantum information processing are subject to detectable loss errors. In this Letter, we show that topological error correcting codes, which protect against computational errors, are also extremely robust against losses. We present analytical results showing that the maximum tolerable loss rate is 50%, which is determined by the square-lattice bond percolation threshold. This saturates the bound set by the no-cloning theorem. Our numerical results support this and show a graceful trade-off between tolerable thresholds for computational and loss errors

Observations and Performance of a Soil Nail Shoring Wall in Seattle Silts and Clays

The Seattle Central Library project, which replaced the existing downtown library, consists of a twelve-story building with several below-grade levels. The excavation encompassed an entire city block and had plan dimensions of approximately 250 feet by 240 feet. The original excavation depth was up to 53 feet in height. The excavation was made in highly overconsolidated Seattle silts and clays (Lawton Clay). The Lawton Clay has been documented to exhibit expansive behavior along planes of weakness associated with stress relief upon excavation. The original excavation was designed to be supported using a tieback soldier pile wall, typical of shoring systems retaining the Lawton Clay. A soil nail shoring wall design was submitted, and subsequently installed, as part of a design-build alternative. The soil nail shoring wall system consisted of temporary, top-down soil nail walls that utilized portions of the concrete basement walls of the existing library. Vertical elements and shotcrete facing were constructed in areas where the excavation extended beyond or below the existing basement walls. Soil nails were installed using self-boring grout-injected anchors consisting of hollow bars with sacrificial drill bits. Displacement of the soil nail shoring walls was predicted to be less than 1 inch by the designer. The actual wall movements for three sides of the excavation were as predicted. However, the east wall on the uphill side of the excavation experienced 4 inches of lateral movement and over 2.5 inches of vertical movement, causing damage to the adjacent street and necessitating extensive design modifications during construction. In addition, the excavation depth was reduced to 47 feet because of significant movement occurring below the excavation. This paper describes the construction and observed behavior of the east wall and the applicability of soil nail walls in the Lawton Clay deposit