7 research outputs found
Event-triggered control and filtering for networked systems based on network dynamics
With the development of computing and communication technology, networked systems
in which information is exchanged through communication networks have become
prevalent in a variety of practical applications. A considerable number of these
systems have scarcely adequate computation and communication network resources.
Notice that, network dynamics usually affect the quality of the performance of networked
systems; network-based control or filtering design generally interferes with
the quality of service of communication networks. Therefore, successful implementation
of networked systems over communication networks requires the adequate
integration of control or filtering with intelligent computation and communication
networks. This research establishes an information scheduling middleware to effi-
ciently utilise the limited communication resources and the computation capacity
while preserving the desired performance of networked systems. In this proposed
middleware, an event-triggered scheme is given to provide a tradeoff between the
performance of networked systems and the utilisation of communication network
resources. A scheduling mechanism is derived to avoid traffic congestion in the
communication network by introducing a fluid-flow model. By using this information
scheduling middleware, the issues of network-based control and filtering are
investigated. First, a fluid-flow model of the communication network and an eventtriggered
scheme are integrated to develop a new framework, in which the criteria
of stability and stabilisation are derived for networked systems under simultaneous
consideration of control system performance and network dynamics. Second, based
on network dynamics, an online scheduling strategy is proposed to design the H∞
filter for networked systems in the framework with the information scheduling middleware,
the Information Dispatching Middleware (IDM). Third, the IDM is applied
to distributed control for large-scale networked systems and a codesign method is
obtained to determine the parameters of the IDM. Fourth, the mechanism of the
IDM is analysed to investigate the cooperation between the Information Selection
Module and the Congestion Avoidance Module in the IDM. Based on the IDM, distributed
filters are designed considering the dynamics of communication networks.
Finally, numerical and practical examples are given to demonstrate the effectiveness
and advantages of the proposed information scheduling middleware
Landslide susceptibility mapping based on particle swarm optimization of multiple kernel relevance vector machines: Case of a low hill area in Sichuan Province, China
In this paper, we propose a multiple kernel relevance vector machine (RVM) method based on the adaptive cloud particle swarm optimization (PSO) algorithm to map landslide susceptibility in the low hill area of Sichuan Province, China. In the multi-kernel structure, the kernel selection problem can be solved by adjusting the kernel weight, which determines the single kernel contribution of the final kernel mapping. The weights and parameters of the multi-kernel function were optimized using the PSO algorithm. In addition, the convergence speed of the PSO algorithm was increased using cloud theory. To ensure the stability of the prediction model, the result of a five-fold cross-validation method was used as the fitness of the PSO algorithm. To verify the results, receiver operating characteristic curves (ROC) and landslide dot density (LDD) were used. The results show that the model that used a heterogeneous kernel (a combination of two different kernel functions) had a larger area under the ROC curve (0.7616) and a lower prediction error ratio (0.28%) than did the other types of kernel models employed in this study. In addition, both the sum of two high susceptibility zone LDDs (6.71/100 km2) and the sum of two low susceptibility zone LDDs (0.82/100 km2) demonstrated that the landslide susceptibility map based on the heterogeneous kernel model was closest to the historical landslide distribution. In conclusion, the results obtained in this study can provide very useful information for disaster prevention and land-use planning in the study area
A lightweight multi-scale context network for salient object detection in optical remote sensing images
No description supplie
Attention Guided Network for Salient Object Detection in Optical Remote Sensing Images
No description supplie
Application of curcumin-mediated antibacterial photodynamic technology for preservation of fresh Tremella Fuciformis
Tremella Fuciformis is an edible fungus with high water content and nutritional values. However, fresh T. Fuciformis can quickly lose its quality by physical damage, water loss and microbial degradation during storage. Herein, we evaluated the effects of curcumin-mediated photodynamic technology (PDT) using light-emitting diode (LED) light to preserve fresh T. Fuciformis. Changes in bacterial counts and community, physicochemical properties, and sensory attributes of curcumin-mediated PDT-treated fresh T. Fuciformis were assessed. The results indicated that treatment with 30 μmol/L curcumin and 30 min of LED light exposure could reduce bacterial counts by ~1.99 ± 0.06 log (CFU/g) in fresh T. Fuciformis upon 5 days storage. The bacterial microbiota in T. Fuciformis during storage was also altered upon PDT treatment. PDT treatment also retained the color, water content, hardness, tactility, and appearance of fresh T. Fuciformis. In conclusion, this study demonstrated that curcumin-mediated PDT could be a viable and promising non-thermal technology for preserving the quality of fresh T. Fuciformis
Multicentre double-blind randomised controlled trial of systematic corticosteroid therapy in patients with acute exacerbations of chronic obstructive pulmonary disease admitted to hospital with higher eosinophil levels: the ECHO protocol
Introduction Corticosteroid is one of the most commonly used medications in patients with acute exacerbations of chronic obstructive pulmonary disease (AECOPD). The increasing understanding of these side-effects of systematic corticosteroids and their better response to treatment among patients with COPD with higher blood eosinophil counts has led to an interest in a more targeted approach to systematic corticosteroid treatment. However, there is a lack of evidence from high-quality randomised controlled trial (RCT) studies about whether initial systematic corticosteroids should be given to patients with AECOPD with elevated eosinophilia. The aim of the present research was to test this hypothesis.
Methods and analysis This is a multicentre, double-blind, superiority RCT in the respiratory departments of 12 general hospitals in China. It is anticipated that 456 patients with AECOPD with a blood eosinophil count >2% or >300 cells/µL at admission will be recruited. Eligible patients will be randomised (1:1) to the intervention group receiving 40 mg oral prednisone daily or identical-appearing placebo (control group) for five consecutive days. Follow-up visits are performed during hospitalisation, followed by clinic interviews on days 30, 60 and 90 after discharge. The primary outcome is treatment failure rates comprising requiring or receiving invasive or non-invasive mechanical ventilation, requiring or transferring to intensive care unit during the index hospitalisation, length of index hospitalisation longer than 14 days, death during the index hospitalisation or within 30 days after discharge and readmission with acute exacerbations of COPD within 30 days after discharge. The results of this trial will provide insight into the value of using blood eosinophil counts as a biomarker of eosinophilic exacerbation and initiating systematic corticosteroid treatment for patients with AECOPD with higher eosinophil levels.
Ethics and dissemination This study was approved by Beijing Chaoyang Hospital Institutional Review Board (approval number: 2020-KE-544) and the main results and secondary results will be published in peer-reviewed journals.
Trial registration number NCT05059873.</p
SCOPE: SCUBA-2 Continuum Observations of Pre-protostellar Evolution - survey description and compact source catalogue
We present the first release of the data and compact-source catalogue for the JCMT Large
Program SCUBA-2 Continuum Observations of Pre-protostellar Evolution (SCOPE). SCOPE
consists of 850 μm continuum observations of 1235 Planck Galactic Cold Clumps (PGCCs)
made with the Submillimetre Common-User Bolometer Array 2 on the James Clerk Maxwell
Telescope. These data are at an angular resolution of 14.4 arcsec, significantly improving upon
the 353 GHz resolution of Planck at 5 arcmin, and allowing for a catalogue of 3528 compact
sources in 558 PGCCs. We find that the detected PGCCs have significant sub-structure,
with 61 per cent of detected PGCCs having three or more compact sources, with filamentary
structure also prevalent within the sample. A detection rate of 45 per cent is found across the
survey, which is 95 per cent complete to Planck column densities of N(H2) > 5 × 10^21 cm^−2.
By positionally associating the SCOPE compact sources with young stellar objects, the star
formation efficiency, as measured by the ratio of luminosity to mass, in nearby clouds is found
to be similar to that in the more distant Galactic Plane, with the column density distributions
also indistinguishable from each other