4,965 research outputs found
A note on the connection between nonextensive entropy and -derivative
In order to study as a whole the major part of entropy measures, we introduce
a two-parameter non-extensive entropic form with respect to the
\textit{h}-derivative which generalizes the conventional Newton-Leibniz
calculus. This new entropy, , is proved to describe the non-extensive
systems and recover several types of the well-known non-extensive entropic
expressions, such as the Tsallis entropy, the Abe entropy, the Shafee entropy,
the Kaniadakis entropy and even the classical Boltzmann\,--\,Gibbs one. As a
generalized entropy, its corresponding properties are also analyzed.Comment: 6 pages, 1 figur
Natural products by synthetic biology and microbial engineering
Natural products are made from simple building blocks, the structural diversity found in natural products is the result of Nature’s intrinsic use of combinatorial biosynthesis, and recent progress in microbial genomics and synthetic biology has sparked the emergence of a suite of contemporary approaches to natural products by microbial engineering and fermentation. Current strategies are mainly based on the collective knowledge of genetics, microbiology, evolution, enzymology, and structural biology that governs the natural product biosynthetic machinery. While successful, they are limited by what information is gleaned from the above disciplines and how that information can be applied to construct the designer pathways. Nature has used evolution over billions of years to become an expert in combinatorial biosynthesis and microbial engineering, and we have only begun to tap into this knowledge. Selected examples from our current researches will be presented to highlight the opportunities in accessing natural products and expanding natural product structural diversity by exploring the vast combinatorial biosynthesis repertoire found in Nature
An ILP Solver for Multi-label MRFs with Connectivity Constraints
Integer Linear Programming (ILP) formulations of Markov random fields (MRFs)
models with global connectivity priors were investigated previously in computer
vision, e.g., \cite{globalinter,globalconn}. In these works, only Linear
Programing (LP) relaxations \cite{globalinter,globalconn} or simplified
versions \cite{graphcutbase} of the problem were solved. This paper
investigates the ILP of multi-label MRF with exact connectivity priors via a
branch-and-cut method, which provably finds globally optimal solutions. The
method enforces connectivity priors iteratively by a cutting plane method, and
provides feasible solutions with a guarantee on sub-optimality even if we
terminate it earlier. The proposed ILP can be applied as a post-processing
method on top of any existing multi-label segmentation approach. As it provides
globally optimal solution, it can be used off-line to generate ground-truth
labeling, which serves as quality check for any fast on-line algorithm.
Furthermore, it can be used to generate ground-truth proposals for weakly
supervised segmentation. We demonstrate the power and usefulness of our model
by several experiments on the BSDS500 and PASCAL image dataset, as well as on
medical images with trained probability maps.Comment: 19 page
Deep Learning Features at Scale for Visual Place Recognition
The success of deep learning techniques in the computer vision domain has
triggered a range of initial investigations into their utility for visual place
recognition, all using generic features from networks that were trained for
other types of recognition tasks. In this paper, we train, at large scale, two
CNN architectures for the specific place recognition task and employ a
multi-scale feature encoding method to generate condition- and
viewpoint-invariant features. To enable this training to occur, we have
developed a massive Specific PlacEs Dataset (SPED) with hundreds of examples of
place appearance change at thousands of different places, as opposed to the
semantic place type datasets currently available. This new dataset enables us
to set up a training regime that interprets place recognition as a
classification problem. We comprehensively evaluate our trained networks on
several challenging benchmark place recognition datasets and demonstrate that
they achieve an average 10% increase in performance over other place
recognition algorithms and pre-trained CNNs. By analyzing the network responses
and their differences from pre-trained networks, we provide insights into what
a network learns when training for place recognition, and what these results
signify for future research in this area.Comment: 8 pages, 10 figures. Accepted by International Conference on Robotics
and Automation (ICRA) 2017. This is the submitted version. The final
published version may be slightly differen
- …