53 research outputs found
Cross-Scale Cost Aggregation for Stereo Matching
Human beings process stereoscopic correspondence across multiple scales.
However, this bio-inspiration is ignored by state-of-the-art cost aggregation
methods for dense stereo correspondence. In this paper, a generic cross-scale
cost aggregation framework is proposed to allow multi-scale interaction in cost
aggregation. We firstly reformulate cost aggregation from a unified
optimization perspective and show that different cost aggregation methods
essentially differ in the choices of similarity kernels. Then, an inter-scale
regularizer is introduced into optimization and solving this new optimization
problem leads to the proposed framework. Since the regularization term is
independent of the similarity kernel, various cost aggregation methods can be
integrated into the proposed general framework. We show that the cross-scale
framework is important as it effectively and efficiently expands
state-of-the-art cost aggregation methods and leads to significant
improvements, when evaluated on Middlebury, KITTI and New Tsukuba datasets.Comment: To Appear in 2013 IEEE Conference on Computer Vision and Pattern
Recognition (CVPR). 2014 (poster, 29.88%
Responses of soil nitrogen mineralization to temperature and moisture in alpine ecosystems on the Tibetan Plateau
AbstractThe responses of soil net nitrogen (N) mineralization to temperature and moisture were investigated in four alpine ecosystems of forest, shrub, meadow and steppe by laboratory incubation method with undisturbed soil cores on the Tibetan Plateau. The results indicated the soil net N mineralization varies greatly between alpine ecosystems. The soil net N mineralization rate in three incubating moisture of forest ecosystem rose markedly, and that of meadow ecosystem rose gently from temperature of 5°C to 35°C, while that of shrub and steppe ecosystems increased from temperature of 5°C to 25°C and reduced from temperature of 25°C to 35°C. At the same incubating temperature, the soil net N mineralization of four alpine ecosystems increased in the middle moisture and deceased in the low or high moisture
Double Dome and Reemergence of Superconductivity in Pristine 6R-TaS2 under Pressure
Investigating the implications of interlayer coupling on superconductivity is
essential for comprehending the intrinsic mechanisms of high temperature
superconductors. Van der Waals heterojunctions have attracted extensive
research due to their exotic interlayer coupling. Here, we present a natural
heterojunction superconductor of 6R-TaS2 that demonstrates a double-dome of
superconductivity, in addition to, the reemergence of superconducting under
high pressures. Our first principles calculation shows that the first dome of
superconductivity in 6R-TaS2 can be attributed to changes in interlayer
coupling and charge transfer. The second superconducting dome and the
reemergence of superconductivity can be ascribed to changes in the density of
states resulting from Fermi surface reconstruction, in which the DOS of T-layer
and S p-orbitals play a crucial role. We have reported the first observation in
TMDs that non-metallic atoms playing a dominant role in the reemergence of
superconducting and the influence of two Lifshitz transitions on
superconducting properties
Protectin conjugates in tissue regeneration 1 alleviates sepsis-induced acute lung injury by inhibiting ferroptosis
Background: Acute lung injury (ALI) is a common and serious complication of sepsis with high mortality. Ferroptosis, categorized as programmed cell death, contributes to the development of lung injury. Protectin conjugates in tissue regeneration 1 (PCTR1) is an endogenous lipid mediator that exerts protective effects against multiorgan injury. However, the role of PCTR1 in the ferroptosis of sepsis-related ALI remains unknown. Methods: A pulmonary epithelial cell line and a mouse model of ALI stimulated with lipopolysaccharide (LPS) were established in vitro and in vivo. Ferroptosis biomarkers, including ferrous (Fe2+), glutathione (GSH), malondialdehyde (MDA) and 4-Hydroxynonenal (4-HNE), were assessed by relevant assay kits. Glutathione peroxidase 4 (GPX4) and prostaglandin-endoperoxide synthase 2 (PTGS2) protein levels were determined by western blotting. Lipid peroxides were examined by fluorescence microscopy and flow cytometry. Cell viability was determined by a CCK-8 assay kit. The ultrastructure of mitochondria was observed with transmission electron microscopy. Morphology and inflammatory cytokine levels predicted the severity of lung injury. Afterward, related inhibitors were used to explore the potential mechanism by which PCTR1 regulates ferroptosis. Results: PCTR1 treatment protected mice from LPS-induced lung injury, which was consistent with the effect of the ferroptosis inhibitor ferrostatin-1. PCTR1 treatment decreased Fe2+, PTGS2 and lipid reactive oxygen species (ROS) contents, increased GSH and GPX4 levels and ameliorated mitochondrial ultrastructural injury. Administration of LPS or the ferroptosis agonist RSL3 resulted in reduced cell viability, which was rescued by PCTR1. Mechanistically, inhibition of the PCTR1 receptor lipoxin A4 (ALX), protein kinase A (PKA) and transcription factor cAMP-response element binding protein (CREB) partly decreased PCTR1 upregulated GPX4 expression and a CREB inhibitor blocked the effects ofPCTR1 on ferroptosis inhibition and lung protection. Conclusion: This study suggests that PCTR1 suppresses LPS-induced ferroptosis via the ALX/PKA/CREB signaling pathway, which may offer promising therapeutic prospects in sepsis-related ALI
Inhibition the ubiquitination of ENaC and Na,K-ATPase with erythropoietin promotes alveolar fluid clearance in sepsis-induced acute respiratory distress syndrome
Sepsis-induced acute respiratory distress syndrome (ARDS) causes significant fatalities worldwide and lacks pharmacological intervention. Alveolar fluid clearance (AFC) plays a pivotal role in the remission of ARDS and is markedly impaired in the pathogenesis of ARDS. Here, we demonstrated that erythropoietin could effectively ameliorate lung injury manifestations and lethality, restore lung function and promote AFC in a rat model of lipopolysaccharide (LPS)-induced ARDS. Moreover, it was proven that EPO-induced restoration of AFC occurs through triggering the total protein expression of ENaC and Na,K-ATPase channels, enhancing their protein abundance in the membrane, and suppressing their ubiquitination for degeneration. Mechanistically, the data indicated the possible involvement of EPOR/JAK2/STAT3/SGK1/Nedd4–2 signaling in this process, and the pharmacological inhibition of the pathway markedly eliminated the stimulating effects of EPO on ENaC and Na,K-ATPase, and subsequently reversed the augmentation of AFC by EPO. Consistently, in vitro studies of alveolar epithelial cells paralleled with that EPO upregulated the expression of ENaC and Na,K-ATPase, and patch-clamp studies further demonstrated that EPO substantially strengthened sodium ion currents. Collectively, EPO could effectively promote AFC by improving ENaC and Na,K-ATPase protein expression and abundance in the membrane, dependent on inhibition of ENaC and Na,K-ATPase ubiquitination, and resulting in diminishing LPS-associated lung injuries
Nitrogen competition between three dominant plant species and microbes in a temperate grassland
Design of a Nonlinear Predictive Controller for a Fractional-Order Hydraulic Turbine Governing System with Mechanical Time Delay
A nonlinear predictive control method for a fractional-order hydraulic turbine governing system (HTGS) with a time delay is studied in this paper. First, a fractional-order model of a time-delay hydraulic turbine governing system is presented. Second, the fractional-order hydraulic servo subsystem is transformed into a standard controlled autoregressive moving average (CARMA) model according to the Grünwald-Letnikov (G-L) definition of fractional calculus. Third, based on the delayed Takagi-Sugeno fuzzy model, the fuzzy prediction model of the integer-order part of the HTGS is given. Then, by introducing a fourth-order Runge-Kutta algorithm, the fuzzy prediction model can be easily transformed into the CARMA model. Furthermore, a nonlinear predictive controller is proposed to stabilize the time-delay HTGS. Finally, the experiment results are consistent with the theoretical analysis
Design of automatic constant-pressure water supply system based on uncertain terminal load
In view of problem that terminal water consumption of water supply system in a mining area cannot be determined, a design scheme of automatic constant-pressure water supply system was put forward. The system uses PLC and frequency converter to control water pump to ensure that the pump power and quantity can be automatically adjusted when terminal loads change greatly, so as to achieve constant pressure water supply. The practical application result shows that the system not only ensures the water pressure required by equipment cooling water system and dustproof water system, but also avoids sharp fluctuation of water pressure and reduces failure rate of equipments on working face
Fractional-Order Finite-Time, Fault-Tolerant Control of Nonlinear Hydraulic-Turbine-Governing Systems with an Actuator Fault
Hydropower units undertake tasks such as peak shaving, frequency modulation, and providing accident reserves in the power system. With the increasing capacity and structural complexity of power systems, hydropower units have become more important. Hydraulic-turbine-governing systems (HTGSs) need to have higher control performance and automation levels to meet the higher regulatory requirements of the power system. To achieve high-quality control, we proposed a new finite-time, fault-tolerant control method for HTGSs with an actuator fault. First, a fractional-order model for HTGSs with uncertainty, external disturbance, and an actuator fault was introduced. Second, a fault estimator that could quickly track the fault signal for an actuator fault was proposed. Then, based on the fractional-order finite-time stability theorem, a finite-time, fault-tolerant controller was proposed for the stabilization of an HTGS. Furthermore, a controller was developed as a fractional differential form combined with a smooth bounded arctangent function to effectively suppress jitters and uncertainties. Finally, numerical experimental results verified the validity and robustness of the proposed scheme
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