2,223 research outputs found
Reliable Asynchronous Image Transfer Protocol in Wireless Multimedia Sensor Networks
In the paper, we propose a reliable asynchronous image transfer protocol, RAIT. RAIT applies a double sliding window method to node-to-node transfer, with one sliding window for the receiving queue, which is used to prevent packet loss caused by communication failure between nodes, and another sliding window for the sending queue, which prevents packet loss caused by network congestion. The routing node prevents packet loss between nodes by preemptive scheduling of multiple packets for a given image. RAIT implements a double sliding window method by means of a cross-layer design between the RAIT layer, routing layer, and queue layer. We demonstrate that RAIT guarantees a higher reliability of image transmission compared to the existing protocols
Beam mask and sliding window-facilitated deep learning-based accurate and efficient dose prediction for pencil beam scanning proton therapy
Purpose: To develop a DL-based PBSPT dose prediction workflow with high
accuracy and balanced complexity to support on-line adaptive proton therapy
clinical decision and subsequent replanning.
Methods: PBSPT plans of 103 prostate cancer patients and 83 lung cancer
patients previously treated at our institution were included in the study, each
with CTs, structure sets, and plan doses calculated by the in-house developed
Monte-Carlo dose engine. For the ablation study, we designed three experiments
corresponding to the following three methods: 1) Experiment 1, the conventional
region of interest (ROI) method. 2) Experiment 2, the beam mask (generated by
raytracing of proton beams) method to improve proton dose prediction. 3)
Experiment 3, the sliding window method for the model to focus on local details
to further improve proton dose prediction. A fully connected 3D-Unet was
adopted as the backbone. Dose volume histogram (DVH) indices, 3D Gamma passing
rates, and dice coefficients for the structures enclosed by the iso-dose lines
between the predicted and the ground truth doses were used as the evaluation
metrics. The calculation time for each proton dose prediction was recorded to
evaluate the method's efficiency.
Results: Compared to the conventional ROI method, the beam mask method
improved the agreement of DVH indices for both targets and OARs and the sliding
window method further improved the agreement of the DVH indices. For the 3D
Gamma passing rates in the target, OARs, and BODY (outside target and OARs),
the beam mask method can improve the passing rates in these regions and the
sliding window method further improved them. A similar trend was also observed
for the dice coefficients. In fact, this trend was especially remarkable for
relatively low prescription isodose lines. The dose predictions for all the
testing cases were completed within 0.25s
A qualitative approach for online activity recognition
We present a novel qualitative, dynamic length sliding window method which enables a mobile robot to temporally segment activities taking place in live RGB-D video. We demonstrate how activities can be learned from observations by encoding qualitative spatio-temporal relationships between entities in the scene. We also show how a Nearest Neighbour model can recognise activities taking place even if they temporally co-occur. Our system is validated on a challenging dataset of daily living activities
Identification of nonlinear time-varying systems using an online sliding-window and common model structure selection (CMSS) approach with applications to EEG
The identification of nonlinear time-varying systems using linear-in-the-parameter models is investigated. A new efficient Common Model Structure Selection (CMSS)
algorithm is proposed to select a common model structure. The main idea and key procedure is: First, generate K 1 data sets (the first K data sets are used for training, and theK 1 th one is used for testing) using an online sliding window method; then detect significant model terms to form a common model structure which fits over all the K
training data sets using the new proposed CMSS approach. Finally, estimate and refine the time-varying parameters for the identified common-structured model using a Recursive Least Squares (RLS) parameter estimation method. The new method can effectively detect and adaptively track the transient variation of nonstationary signals. Two examples are presented to illustrate the effectiveness of the new approach including an application to an EEG data set
Detection and characterization of local inverted repeats regularities
To explore the inverted repeats regularities along the genome sequences, we propose a sliding window method to extract the concentration scores of inverted repeats periodic regularities and the total mass of possible inverted repeats pairs. We apply the method to the human genome and locate the regions with the potential for the formation of large number of hairpin/cruciform structures. The number of found windows with periodic regularities is small and the patterns of occurrence are chromosome specific.publishe
Symbolic local information transfer
Recently, the permutation-information theoretic approach has been used in a
broad range of research fields. In particular, in the study of highdimensional
dynamical systems, it has been shown that this approach can be effective in
characterizing global properties, including the complexity of their
spatiotemporal dynamics. Here, we show that this approach can also be applied
to reveal local spatiotemporal profiles of distributed computations existing at
each spatiotemporal point in the system. J. T. Lizier et al. have recently
introduced the concept of local information dynamics, which consists of
information storage, transfer, and modification. This concept has been
intensively studied with regard to cellular automata, and has provided
quantitative evidence of several characteristic behaviors observed in the
system. In this paper, by focusing on the local information transfer, we
demonstrate that the application of the permutation-information theoretic
approach, which introduces natural symbolization methods, makes the concept
easily extendible to systems that have continuous states. We propose measures
called symbolic local transfer entropies, and apply these measures to two test
models, the coupled map lattice (CML) system and the Bak-Sneppen model
(BS-model), to show their relevance to spatiotemporal systems that have
continuous states.Comment: 20 pages, 7 figure
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