92,193 research outputs found
ON IMPLEMENTATION OF ROBUST AUTOTUNING OF TRANSMISSION ELECTRON MICROSCOPES
Practice shows that the current impiementations of automatic tuning of transmission elec-
tron microscopes suffer from not satisfactory robustness, and this seriously limits their
applicability. The paper presents a software architecture which provides a framework for
the realization of a real-time automatic tuning system with improved robustness. First
the transmission electron microscope tuning as general measuring/modelling process is
characterized and the consequences of the improvement in robustness are identified in
this context. It is concluded that both extending the models of image formation of the
electron microscope into qualitative and heuristic directions, and the continuous model
validation with sophisticated control are necessary for coping with these problems. Then
a two-layer software architecture is presented which helps satisfying the above require-
ments to a considerable extent: the lower layer contains the conventional and symbolic
data/image processing components (with data/control interfaces), the upper layer - us-
ing knowledge based approach extensively - realizes the higher level control based on the
partial results of the processing on the lower level. (Hence, the upper level is responsible
for the robustness in system-wide sense.) Main subsystems of the autotuning software are
shown. A short survey of the hardware background is also given. A summary closes the
paper
Rationale in Development Chat Messages: An Exploratory Study
Chat messages of development teams play an increasingly significant role in
software development, having replaced emails in some cases. Chat messages
contain information about discussed issues, considered alternatives and
argumentation leading to the decisions made during software development. These
elements, defined as rationale, are invaluable during software evolution for
documenting and reusing development knowledge. Rationale is also essential for
coping with changes and for effective maintenance of the software system.
However, exploiting the rationale hidden in the chat messages is challenging
due to the high volume of unstructured messages covering a wide range of
topics. This work presents the results of an exploratory study examining the
frequency of rationale in chat messages, the completeness of the available
rationale and the potential of automatic techniques for rationale extraction.
For this purpose, we apply content analysis and machine learning techniques on
more than 8,700 chat messages from three software development projects. Our
results show that chat messages are a rich source of rationale and that machine
learning is a promising technique for detecting rationale and identifying
different rationale elements.Comment: 11 pages, 6 figures. The 14th International Conference on Mining
Software Repositories (MSR'17
Constrained Design of Deep Iris Networks
Despite the promise of recent deep neural networks in the iris recognition
setting, there are vital properties of the classic IrisCode which are almost
unable to be achieved with current deep iris networks: the compactness of model
and the small number of computing operations (FLOPs). This paper re-models the
iris network design process as a constrained optimization problem which takes
model size and computation into account as learning criteria. On one hand, this
allows us to fully automate the network design process to search for the best
iris network confined to the computation and model compactness constraints. On
the other hand, it allows us to investigate the optimality of the classic
IrisCode and recent iris networks. It also allows us to learn an optimal iris
network and demonstrate state-of-the-art performance with less computation and
memory requirements
Automated Home Oxygen Delivery for Patients with COPD and Respiratory Failure: A New Approach
Long-term oxygen therapy (LTOT) has become standard care for the treatment of patients with chronic obstructive pulmonary disease (COPD) and other severe hypoxemic lung diseases. The use of new portable O-2 concentrators (POC) in LTOT is being expanded. However, the issue of oxygen titration is not always properly addressed, since POCs rely on proper use by patients. The robustness of algorithms and the limited reliability of current oximetry sensors are hindering the effectiveness of new approaches to closed-loop POCs based on the feedback of blood oxygen saturation. In this study, a novel intelligent portable oxygen concentrator (iPOC) is described. The presented iPOC is capable of adjusting the O-2 flow automatically by real-time classifying the intensity of a patient's physical activity (PA). It was designed with a group of patients with COPD and stable chronic respiratory failure. The technical pilot test showed a weighted accuracy of 91.1% in updating the O-2 flow automatically according to medical prescriptions, and a general improvement in oxygenation compared to conventional POCs. In addition, the usability achieved was high, which indicated a significant degree of user satisfaction. This iPOC may have important benefits, including improved oxygenation, increased compliance with therapy recommendations, and the promotion of PA
Robust sound event detection in bioacoustic sensor networks
Bioacoustic sensors, sometimes known as autonomous recording units (ARUs),
can record sounds of wildlife over long periods of time in scalable and
minimally invasive ways. Deriving per-species abundance estimates from these
sensors requires detection, classification, and quantification of animal
vocalizations as individual acoustic events. Yet, variability in ambient noise,
both over time and across sensors, hinders the reliability of current automated
systems for sound event detection (SED), such as convolutional neural networks
(CNN) in the time-frequency domain. In this article, we develop, benchmark, and
combine several machine listening techniques to improve the generalizability of
SED models across heterogeneous acoustic environments. As a case study, we
consider the problem of detecting avian flight calls from a ten-hour recording
of nocturnal bird migration, recorded by a network of six ARUs in the presence
of heterogeneous background noise. Starting from a CNN yielding
state-of-the-art accuracy on this task, we introduce two noise adaptation
techniques, respectively integrating short-term (60 milliseconds) and long-term
(30 minutes) context. First, we apply per-channel energy normalization (PCEN)
in the time-frequency domain, which applies short-term automatic gain control
to every subband in the mel-frequency spectrogram. Secondly, we replace the
last dense layer in the network by a context-adaptive neural network (CA-NN)
layer. Combining them yields state-of-the-art results that are unmatched by
artificial data augmentation alone. We release a pre-trained version of our
best performing system under the name of BirdVoxDetect, a ready-to-use detector
of avian flight calls in field recordings.Comment: 32 pages, in English. Submitted to PLOS ONE journal in February 2019;
revised August 2019; published October 201
High-Throughput System for the Early Quantification of Major Architectural Traits in Olive Breeding Trials Using UAV Images and OBIA Techniques
The need for the olive farm modernization have encouraged the research of more efficient crop management strategies through cross-breeding programs to release new olive cultivars more suitable for mechanization and use in intensive orchards, with high quality production and resistance to biotic and abiotic stresses. The advancement of breeding programs are hampered by the lack of efficient phenotyping methods to quickly and accurately acquire crop traits such as morphological attributes (tree vigor and vegetative growth habits), which are key to identify desirable genotypes as early as possible. In this context, an UAV-based high-throughput system for olive breeding program applications was developed to extract tree traits in large-scale phenotyping studies under field conditions. The system consisted of UAV-flight configurations, in terms of flight altitude and image overlaps, and a novel, automatic, and accurate object-based image analysis (OBIA) algorithm based on point clouds, which was evaluated in two experimental trials in the framework of a table olive breeding program, with the aim to determine the earliest date for suitable quantifying of tree architectural traits. Two training systems (intensive and hedgerow) were evaluated at two very early stages of tree growth: 15 and 27 months after planting. Digital Terrain Models (DTMs) were automatically and accurately generated by the algorithm as well as every olive tree identified, independently of the training system and tree age. The architectural traits, specially tree height and crown area, were estimated with high accuracy in the second flight campaign, i.e. 27 months after planting. Differences in the quality of 3D crown reconstruction were found for the growth patterns derived from each training system. These key phenotyping traits could be used in several olive breeding programs, as well as to address some agronomical goals. In addition, this system is cost and time optimized, so that requested architectural traits could be provided in the same day as UAV flights. This high-throughput system may solve the actual bottleneck of plant phenotyping of "linking genotype and phenotype," considered a major challenge for crop research in the 21st century, and bring forward the crucial time of decision making for breeders
Where are your Manners? Sharing Best Community Practices in the Web 2.0
The Web 2.0 fosters the creation of communities by offering users a wide
array of social software tools. While the success of these tools is based on
their ability to support different interaction patterns among users by imposing
as few limitations as possible, the communities they support are not free of
rules (just think about the posting rules in a community forum or the editing
rules in a thematic wiki). In this paper we propose a framework for the sharing
of best community practices in the form of a (potentially rule-based)
annotation layer that can be integrated with existing Web 2.0 community tools
(with specific focus on wikis). This solution is characterized by minimal
intrusiveness and plays nicely within the open spirit of the Web 2.0 by
providing users with behavioral hints rather than by enforcing the strict
adherence to a set of rules.Comment: ACM symposium on Applied Computing, Honolulu : \'Etats-Unis
d'Am\'erique (2009
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