75 research outputs found
Experimental Observation of Classical Sub-Wavelength Interference with Thermal-Like Light
We show the experimental observation of the classical sub-wavelength
double-slit interference with a pseudo-thermal light source. The experimental
results are in agreement with the recent theoretical prediction shown in
quant-ph/0404078 (to be appeared in Phys. Rev. A).Comment: 4 pages, 6 figure
Split Learning over Wireless Networks: Parallel Design and Resource Management
Split learning (SL) is a collaborative learning framework, which can train an
artificial intelligence (AI) model between a device and an edge server by
splitting the AI model into a device-side model and a server-side model at a
cut layer. The existing SL approach conducts the training process sequentially
across devices, which incurs significant training latency especially when the
number of devices is large. In this paper, we design a novel SL scheme to
reduce the training latency, named Cluster-based Parallel SL (CPSL) which
conducts model training in a "first-parallel-then-sequential" manner.
Specifically, the CPSL is to partition devices into several clusters,
parallelly train device-side models in each cluster and aggregate them, and
then sequentially train the whole AI model across clusters, thereby
parallelizing the training process and reducing training latency. Furthermore,
we propose a resource management algorithm to minimize the training latency of
CPSL considering device heterogeneity and network dynamics in wireless
networks. This is achieved by stochastically optimizing the cut layer
selection, real-time device clustering, and radio spectrum allocation. The
proposed two-timescale algorithm can jointly make the cut layer selection
decision in a large timescale and device clustering and radio spectrum
allocation decisions in a small timescale. Extensive simulation results on
non-independent and identically distributed data demonstrate that the proposed
solutions can greatly reduce the training latency as compared with the existing
SL benchmarks, while adapting to network dynamics.Comment: The paper has been submitted to IEEE Journal on Selected Areas in
Communication
Data Driven Chiller Plant Energy Optimization with Domain Knowledge
Refrigeration and chiller optimization is an important and well studied topic
in mechanical engineering, mostly taking advantage of physical models, designed
on top of over-simplified assumptions, over the equipments. Conventional
optimization techniques using physical models make decisions of online
parameter tuning, based on very limited information of hardware specifications
and external conditions, e.g., outdoor weather. In recent years, new generation
of sensors is becoming essential part of new chiller plants, for the first time
allowing the system administrators to continuously monitor the running status
of all equipments in a timely and accurate way. The explosive growth of data
flowing to databases, driven by the increasing analytical power by machine
learning and data mining, unveils new possibilities of data-driven approaches
for real-time chiller plant optimization. This paper presents our research and
industrial experience on the adoption of data models and optimizations on
chiller plant and discusses the lessons learnt from our practice on real world
plants. Instead of employing complex machine learning models, we emphasize the
incorporation of appropriate domain knowledge into data analysis tools, which
turns out to be the key performance improver over state-of-the-art deep
learning techniques by a significant margin. Our empirical evaluation on a real
world chiller plant achieves savings by more than 7% on daily power
consumption.Comment: CIKM2017. Proceedings of the 26th ACM International Conference on
Information and Knowledge Management. 201
Artificial intelligence planning and 3D printing augmented modules in the treatment of a complicated hip joint revision: a case report
Total hip revision with osseous defects can be very difficult. Artificial intelligence offers preoperative planning, real-time measurement, and intraoperative judgment, which can guide prothesis placement more accurately. Three-dimensional printed metel augment modules which are made according to the individualized osseous anatomy, can fit the osseous defects well and provide mechanical support. In this case, we used AI to plan the size and position of the acetabular cup and 3D-printed augmented modules in a complicated hip revision with an acetabular bone defects, which achieved stable fixation and relieved hip pain postoperatively
Label-Free Spectral Imaging Unveils Biochemical Mechanisms of Low-Level Laser Therapy on Spinal Cord Injury
Background/Aims: Low-level laser therapy (LLLT) leads to complex photochemical responses during the healing process of spinal cord injury (SCI). Confocal Raman Microspectral Imaging (in combination with multivariate analysis) was adopted to illustrate the underlying biochemical mechanisms of LLLT treatment on a SCI rat model. Methods: Using transversal tissue sections, the Raman spectra can identify areas neighboring the injury site, glial scar, cavity, and unharmed white matter, as well as their correlated cellular alterations, such as demyelination and up-regulation of chondroitin sulfate proteoglycans (CSPGs). Multivariate data analysis methods are used to depict the underlying therapeutic effects by highlighting the detailed content and distribution variations of the biochemical constituents. Results: It is confirmed that photon-tissue interactions might lead to a decay of the inhibitory response to remyelination by suppressing CSPG expression, as also morphologically demonstrated by reduced glial scar and cavity areas. An inter-group comparison semi-quantitatively confirms changes in lipids, phosphatidic acid, CSPGs, and cholesterol during SCI and its LLLT treatment, paving the way for in vitro and in vivo understanding of the biochemical changes accompanying pathobiological SCI events. Conclusion: The achieved results in this work not only have once again proved the well-known cellular mechanisms of SCI, but further illustrate the underlying biochemical variability during LLLT treatment, which provide a sound basis for developing real-time Raman methodologies to monitor the efficacy of the SCI LLLT treatment
Efficacy of early prone or lateral positioning in patients with severe COVID-19: a single-center prospective cohort
Abstract Background Position intervention has been shown to improve oxygenation, but its role in non-invasively ventilated patients with severe COVID-19 has not been assessed. The objective of this study was to investigate the efficacy of early position intervention on non-invasively ventilated patients with severe COVID-19. Methods This was a single-center, prospective observational study in consecutive patients with severe COVID-19 managed in a provisional ICU at Renmin Hospital of Wuhan University from 31 January to 15 February 2020. Patients with chest CT showing exudation or consolidation in bilateral peripheral and posterior parts of the lungs were included. Early position intervention (prone or lateral) was commenced for &gt; 4 hours daily for 10 days in these patients, while others received standard care. Results The baseline parameters were comparable between the position intervention group (n = 17) and the standard care group (n = 35). Position intervention was well-tolerated and increased cumulative adjusted mean difference of SpO2/FiO2 (409, 95% CI 86 to 733) and ROX index (26, 95% CI 9 to 43) with decreased Borg scale (−9, 95% CI −15 to −3) during the first 7 days. It also facilitated absorption of lung lesions and reduced the proportion of patients with high National Early Warning Score 2 (≥ 7) on days 7 and 14, with a trend toward faster clinical improvement. Virus shedding and length of hospital stay were comparable between the two groups. Conclusions This study provides the first evidence for improved oxygenation and lung lesion absorption using early position intervention in non-invasively ventilated patients with severe COVID-19, and warrants further randomized trials. </jats:sec
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