462 research outputs found
Towards Ghost-free Shadow Removal via Dual Hierarchical Aggregation Network and Shadow Matting GAN
Shadow removal is an essential task for scene understanding. Many studies
consider only matching the image contents, which often causes two types of
ghosts: color in-consistencies in shadow regions or artifacts on shadow
boundaries. In this paper, we tackle these issues in two ways. First, to
carefully learn the border artifacts-free image, we propose a novel network
structure named the dual hierarchically aggregation network~(DHAN). It contains
a series of growth dilated convolutions as the backbone without any
down-samplings, and we hierarchically aggregate multi-context features for
attention and prediction, respectively. Second, we argue that training on a
limited dataset restricts the textural understanding of the network, which
leads to the shadow region color in-consistencies. Currently, the largest
dataset contains 2k+ shadow/shadow-free image pairs. However, it has only 0.1k+
unique scenes since many samples share exactly the same background with
different shadow positions. Thus, we design a shadow matting generative
adversarial network~(SMGAN) to synthesize realistic shadow mattings from a
given shadow mask and shadow-free image. With the help of novel masks or
scenes, we enhance the current datasets using synthesized shadow images.
Experiments show that our DHAN can erase the shadows and produce high-quality
ghost-free images. After training on the synthesized and real datasets, our
network outperforms other state-of-the-art methods by a large margin. The code
is available: http://github.com/vinthony/ghost-free-shadow-removal/Comment: Accepted by AAAI 202
An electron acceptor molecule in a nanomesh: F4TCNQ on h-BN/Rh(111)
The adsorption of molecules on surfaces affects the surface dipole and thus
changes in the work function may be expected. The effect in change of work
function is particularly strong if charge between substrate and adsorbate is
involved. Here we report the deposition of a strong electron acceptor molecule,
tetrafluorotetracyanoquinodimethane CFN (FTCNQ) on a
monolayer of hexagonal boron nitride nanomesh (-BN on Rh(111)). The work
function of the FTCNQ/-BN/Rh system increases upon increasing
molecular coverage. The magnitude of the effect indicates electron transfer
from the substrate to the FTCNQ molecules. Density functional theory
calculations confirm the work function shift and predict doubly charged
FTCNQ in the nanomesh pores, where the -BN is closest to the Rh
substrate, and to have the largest binding energy there. The preferred
adsorption in the pores is conjectured from a series of ultraviolet
photoelectron spectroscopy data, where the bands in the pores are
first attenuated. Scanning tunneling microscopy measurements indicate that
FTCNQ molecules on the nanomesh are mobile at room temperature, as
"hopping" between neighboring pores is observed
Fault Mode Probability Factor Based Fault-Tolerant Control for Dissimilar Redundant Actuation System
This paper presents a Fault Mode Probability Factor (FMPF) based Fault-Tolerant Control (FTC) strategy for multiple faults of Dissimilar Redundant Actuation System (DRAS) composed of Hydraulic Actuator (HA) and Electro-Hydrostatic Actuator (EHA). The long-term service and severe working conditions can result in multiple gradual faults which can ultimately degrade the system performance, resulting in the system model drift into the fault state characterized with parameter uncertainty. The paper proposes to address this problem by using the historical statistics of the multiple gradual faults and the proposed FMPF to amend the system model with parameter uncertainty. To balance the system model precision and computation time, a Moving Window (MW) method is used to determine the applied historical statistics. The FMPF based FTC strategy is developed for the amended system model where the system estimation and Linear Quadratic Regulator (LQR) are updated at the end of system sampling period. The simulations of DRAS system subjected to multiple faults have been performed and the results indicate the effectiveness of the proposed approach
Active Fault Tolerant Control for Vertical Tail Damaged Aircraft with Dissimilar Redundant Actuation System
This paper proposes an active fault-tolerant control strategy for an aircraft with dissimilar redundant actuation system (DRAS) that has suffered from vertical tail damage. A damage degree coefficient based on the effective vertical tail area is introduced to parameterize the damaged flight dynamic model. The nonlinear relationship between the damage degree coefficient and the corresponding stability derivatives is considered. Furthermore, the performance degradation of new input channel with electro-hydrostatic actuator (EHA) is also taken into account in the damaged flight dynamic model. Based on the accurate damaged flight dynamic model, a composite method of linear quadratic regulator (LQR) integrating model reference adaptive control (MRAC) is proposed to reconfigure the fault-tolerant control law. The numerical simulation results validate the effectiveness of the proposed fault-tolerant control strategy with accurate flight dynamic model. The results also indicate that aircraft with DRAS has better fault-tolerant control ability than the traditional ones when the vertical tail suffers from serious damage. © 2016 Chinese Society of Aeronautics and Astronautic
Influence of acupuncture on cognitive function and markers of oxidative DNA damage in patients with vascular dementia
AbstractObjectiveTo test the influence of acupuncture on cognitive function and a marker of oxidative DNA damage in patients with vascular dementia (VD).MethodsSixteen VD patients were evaluated before and after acupuncture, using the Folstein Mini-Mental State Examination-Revised (MMSE-R) to assess cognitive function, and the ADL-R scale to assess independence in activities of daily living (ADL). Life quality was evaluated using the DEMQOL (Dementia quality of life questionnaire) questionnaire, and syndromes and expression of vascular dementia were evaluated with the Scale for the Differentiation of Syndromes of Vascular Dementia (SDSVD). In addition, the urine concentration of 8-hydroxy-2âČ-deoxyguanosine (8-OHdG) âa marker of oxidative damageâwas quantified with enzyme-linked immunosorbent assay.ResultsThe MMSE-R and DEMQOL scores were higher after acupuncture than before (P<0.05), while there were no obvious differences in the ADL-R or SDSVD scores (P>0.05). The 8-OHdG content in urine significantly decreased after acupuncture (P<0.05).ConclusionAcupuncture reduces the levels of 8-OHdG and improves cognitive function and quality of life in VD patients, suggesting that acupuncture is beneficial at least in part by preventing oxidative damage
In vitro - in vivo - in silico approach in the development of inhaled drug products: Nanocrystal-based formulations with budesonide as a model drug
This study aims to understand the absorption patterns of three different kinds of inhaled formulations via in silico modeling using budesonide (BUD) as a model drug. The formulations investigated in this study are: (i) commercially available micronized BUD mixed with lactose (BUD-PT), (ii) BUD nanocrystal suspension (BUD-NC), (iii) BUD nanocrystals embedded hyaluronic acid microparticles (BUD-NEM). The deposition patterns of the three inhaled formulations in the ratsâ lungs were determined in vivo and in silico predicted, which were used as inputs in GastroPlusâą software to predict drug absorption following aerosolization of the tested formulations. BUD pharmacokinetics, estimated based on intravenous data in rats, was used to establish a drug-specific in silico absorption model. The BUD-specific in silico model revealed that drug pulmonary solubility and absorption rate constant were the key factors affecting pulmonary absorption of BUD-NC and BUD-NEM, respectively. In the case of BUD-PT, the in silico model revealed significant gastrointestinal absorption of BUD, which could be overlooked by traditional in vivo experimental observation. This study demonstrated that in vitro-in vivo-in silico approach was able to identify the key factors that influence the absorption of different inhaled formulations, which may facilitate the development of orally inhaled formulations with different drug release/absorption rates
Nanodiamond-Gutta Percha Composite Biomaterials for Root Canal Therapy.
Root canal therapy (RCT) represents a standard of treatment that addresses infected pulp tissue in teeth and protects against future infection. RCT involves removing dental pulp comprising blood vessels and nerve tissue, decontaminating residually infected tissue through biomechanical instrumentation, and root canal obturation using a filler material to replace the space that was previously composed of dental pulp. Gutta percha (GP) is typically used as the filler material, as it is malleable, inert, and biocompatible. While filling the root canal space with GP is the standard of care for endodontic therapies, it has exhibited limitations including leakage, root canal reinfection, and poor mechanical properties. To address these challenges, clinicians have explored the use of alternative root filling materials other than GP. Among the classes of materials that are being explored as novel endodontic therapy platforms, nanodiamonds (NDs) may offer unique advantages due to their favorable properties, particularly for dental applications. These include versatile faceted surface chemistry, biocompatibility, and their role in improving mechanical properties, among others. This study developed a ND-embedded GP (NDGP) that was functionalized with amoxicillin, a broad-spectrum antibiotic commonly used for endodontic infection. Comprehensive materials characterization confirmed improved mechanical properties of NDGP over unmodified GP. In addition, digital radiography and microcomputed tomography imaging demonstrated that obturation of root canals with NDGP could be achieved using clinically relevant techniques. Furthermore, bacterial growth inhibition assays confirmed drug functionality of NDGP functionalized with amoxicillin. This study demonstrates a promising path toward NDGP implementation in future endodontic therapy for improved treatment outcomes
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