1,999 research outputs found
FootSLAM meets adaptive thresholding
The is the author accepted manuscript. The final version is available from IEEE via the DOI in this recordCalibration of the zero-velocity detection threshold is an essential prerequisite for zero-velocity-aided inertial navigation. However, the literature is lacking a self-contained calibration method, suitable for large-scale use in unprepared environments without map information or pre-deployed infrastructure. In this paper, the calibration of the zero-velocity detection threshold is formulated as a maximum likelihood problem. The likelihood function is approximated using estimation quantities readily available from the FootSLAM algorithm. Thus, we obtain a method for adaptive thresholding that does not require map information, measurements from supplementary sensors, or user input. Experimental evaluations are conducted using data with different gait speeds, sensor placements, and walking trajectories. The proposed calibration method is shown to outperform fixed-threshold zero-velocity detectors and a benchmark using a speed-based threshold classifier.National Institute of Standards and Technology (NIST
The self-assembly of DNA Holliday junctions studied with a minimal model
In this paper, we explore the feasibility of using coarse-grained models to
simulate the self-assembly of DNA nanostructures. We introduce a simple model
of DNA where each nucleotide is represented by two interaction sites
corresponding to the phosphate-sugar backbone and the base. Using this model,
we are able to simulate the self-assembly of both DNA duplexes and Holliday
junctions from single-stranded DNA. We find that assembly is most successful in
the temperature window below the melting temperatures of the target structure
and above the melting temperature of misbonded aggregates. Furthermore, in the
case of the Holliday junction, we show how a hierarchical assembly mechanism
reduces the possibility of becoming trapped in misbonded configurations. The
model is also able to reproduce the relative melting temperatures of different
structures accurately, and allows strand displacement to occur.Comment: 13 pages, 14 figure
Map-aided navigation for emergency searches
This is the author accepted manuscript. The final version is available from the publisher via the DOI in this recordReal-time positioning of emergency personnel has
been an active research topic for many years. However, studies on
how to improve navigation accuracy by using prior information
on the idiosyncratic motion characteristics of firefighters are
scarce. This paper presents an algorithm for generating pseudo
observations of position and orientation based on standard search
patterns used by firefighters. The iterative closest point algorithm
is used to compare walking trajectories estimated from inertial
odometry with search patterns generated from digital maps. The
resulting fitting errors are then used to integrate the pseudo
observations into a map-aided navigation filter. Specifically, we
present a sequential Monte Carlo solution where the pattern
comparison is used to both update particle weights and create
new particle samples. Experimental results involving professional
firefighters demonstrate that the proposed pseudo observations
can achieve a stable localization error of about one meter, and
offer increased robustness in the presence of map errors
Perspectives on Adoption from Christian Adoptive Parents: A Qualitative Study
Although adoption has long been studied, the rising current evangelical trend of adopting has brought about a new series of questions, mostly pertaining to, âWhat is it like to be a Christian adoptive parent?â The research goals were to understand how faith motivates oneâs decision to adopt and the assimilation of the adopted child into the family, to examine the parallels between theological adoption and human experience adoption, and to see if parents have a qualitatively different kind of bonding or affection for their biological and adoptive children. This qualitative research study was conducted through semi-structured interviews with practicing Christians who have both biological and adopted children. Several major themes emerged from these qualitative interviews, some of which pertain to: the theological or spiritual reasons for adoption, a more concrete understand of theological constructs, the importance of names, and âadoption legacy.
3D Object reconstruction from a single depth view with adversarial learning
In this paper, we propose a novel 3D-RecGAN approach, which reconstructs the complete 3D structure of a given object from a single arbitrary depth view using generative adversarial networks. Unlike the existing work which typically requires multiple views of the same object or class labels to recover the full 3D geometry, the proposed 3D-RecGAN only takes the voxel grid representation of a depth view of the object as input, and is able to generate the complete 3D occupancy grid by filling in the occluded/missing regions. The key idea is to combine the generative capabilities of autoencoders and the conditional Generative Adversarial Networks (GAN) framework, to infer accurate and fine-grained 3D structures of objects in high-dimensional voxel space. Extensive experiments on large synthetic datasets show that the proposed 3D-RecGAN significantly outperforms the state of the art in single view 3D object reconstruction, and is able to reconstruct unseen types of objects. Our code and data are available at: https://github.com/Yang7879/3D-RecGAN
Discovery of a novel biomarker in the urine in women with endometriosis
Objective: To investigate whether proteins secreted in urine differ between women with and without endometriosis. Design: Laboratory study using human urine. Setting: University-based laboratory. Patient(s): Women with and without endometriosis undergoing laparoscopy, hysteroscopy and curettage. Intervention(s): Urine collection from women with and without endometriosis. Main Outcome Measure(s): Proteomic techniques and mass spectrometry to identify proteins secreted in the urine of women with and without endometriosis. Result(s): On average, 133 proteins were significantly different between women with and without endometriosis. Cytokeratin-19 was highly up-regulated in the urine of women with endometriosis. Conclusion(s): Cytokeratin-19 may be a valuable urinary biomarker for endometriosis. © 2011 American Society for Reproductive Medicine, Published by Elsevier Inc
The maximally entangled symmetric state in terms of the geometric measure
The geometric measure of entanglement is investigated for permutation
symmetric pure states of multipartite qubit systems, in particular the question
of maximum entanglement. This is done with the help of the Majorana
representation, which maps an n qubit symmetric state to n points on the unit
sphere. It is shown how symmetries of the point distribution can be exploited
to simplify the calculation of entanglement and also help find the maximally
entangled symmetric state. Using a combination of analytical and numerical
results, the most entangled symmetric states for up to 12 qubits are explored
and discussed. The optimization problem on the sphere presented here is then
compared with two classical optimization problems on the S^2 sphere, namely
Toth's problem and Thomson's problem, and it is observed that, in general, they
are different problems.Comment: 18 pages, 15 figures, small corrections and additions to contents and
reference
Efficient solution-processed dendrimer OLEDs
Light-emitting dendrimers are a new distinct class of material for OLEDs. Dendrimers consist of a light-emitting core, dendrons and surface groups. Dendrimers are designed for solution coating and have a number of advantages over conjugated polymers. We report our recent results for solution processed green dendrimer OLEDs. The OLEDs were fabricated by spin-coating a blend of first generation dendrimer/host material followed by the evaporation of a hole blocking layer and a LiF/Al cathode. Power efficiencies of 50 lm/W at practical brightness levels were achieved for these structures
Tracking the reflexivity of the (dis)engaged citizen: some methodological reflections
The relationship between governments and citizens in many contemporary democracies is haunted by uncertainty and sociologists face the task of listening effectively to citizensâ own reflections on this uncertain relationship. This article reflects on the qualitative methodology of a recently completed UK project which used a combination of diary and multiple interviews/ focus groups to track over a fieldwork period of up to a year citizensâ reflections on their relationship to a public world and the contribution to this of their media consumption. In particular, the article considers how the projectâs multiple methods enabled multiple angles on the inevitable artificiality and performative dimension of the diary process, resulting in rich data on peopleâs complex reflections on the uncertain position of the contemporary citizen
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