60 research outputs found

    Consecutive Inertia Drift of Autonomous RC Car via Primitive-based Planning and Data-driven Control

    Full text link
    Inertia drift is an aggressive transitional driving maneuver, which is challenging due to the high nonlinearity of the system and the stringent requirement on control and planning performance. This paper presents a solution for the consecutive inertia drift of an autonomous RC car based on primitive-based planning and data-driven control. The planner generates complex paths via the concatenation of path segments called primitives, and the controller eases the burden on feedback by interpolating between multiple real trajectories with different initial conditions into one near-feasible reference trajectory. The proposed strategy is capable of drifting through various paths containing consecutive turns, which is validated in both simulation and reality.Comment: 9 pages, 10 figures, to appear to IROS 202

    Treatment of vulval condyloma with a combination of paiteling and cryotherapy, and its effect on late recurrence

    Get PDF
    Purpose: To study the clinical effectiveness of a combination of Paiteling and cryotherapy in the treatment of vulval condyloma acuminatum (VCA), and its effect on late recurrence. Methods: Eighty-six VCA patients were chosen as research subjects, and were randomized into group A and group B. Group A patients were treated with combination of Paiteling and cryotherapy, while group B patients received cryotherapy only. The clinical effects of the two treatment methods on VCA were evaluated by measuring area of damaged skin, levels of interleukin-6 (IL-6) and C-reactive protein (CRP), as well as degree of recurrence of VCA in the two groups, before and after treatment. Results: Total clinical treatment effectiveness in group A was significantly higher compared with group B (p < 0.05). After treatment, the area of damaged skin, and levels of IL-6 and CRP were markedly lower in group A than in group B (p < 0.001). After 6 months of treatment, disease control was higher in group A than in group B (p < 0.05). There was also a lower incidence of adverse reactions in group A than in group B (p < 0.05). Conclusion: These results indicate that the combination of Paiteling and cryotherapy is more effective than cryotherapy alone in improving treatment effectiveness and reducing late recurrence of VCA. Therefore, the combined treatment has potentials clinical application in the management of VCA

    Ultrahigh-Frequency Surface Acoustic Wave Sensors with Giant Mass-Loading Effects on Electrodes

    Get PDF
    Surface acoustic wave (SAW) devices are widely used for physical, chemical, and biological sensing applications, and their sensing mechanisms are generally based on frequency changes due to mass-loading effects at the acoustic wave propagation area between two interdigitated transducers (IDTs). In this paper, a new sensing mechanism has been proposed based on a significantly enhanced mass-loading effect generated directly on Au IDT electrodes, which enables significantly enhanced sensitivity, compared with that of conventional SAW devices. The fabricated ultrahigh-frequency SAW devices show a significant mass-loading effect on the electrodes. When the Au-electrode thickness increased from 12 to 25 nm, the Rayleigh mode resonant frequency decreased from 7.77 to 5.93 GHz, while that of the higher longitudinal leaky SAW decreased from 11.87 to 9.83 GHz. The corresponding mass sensitivity of 7309 MHz·mm2·μg–1 (Rayleigh mode) is ∼8.9 × 1011 times larger than that of a conventional quartz crystal balance (with a frequency of 5 MHz) and ∼1000 times higher than that of conventional SAW devices (with a frequency of 978 MHz). Trinitrotoluene concentration as low as 4.4 × 10–9 M (mol·L–1) can be detected using the fabricated SAW sensor, proving its giant mass-loading effect and ultrahigh sensitivity

    Platelet-Rich Plasma Promotes the Proliferation of Human Muscle Derived Progenitor Cells and Maintains Their Stemness

    Get PDF
    Human muscle-derived progenitor cells (hMDPCs) offer great promise for muscle cell-based regenerative medicine; however, prolonged ex-vivo expansion using animal sera is necessary to acquire sufficient cells for transplantation. Due to the risks associated with the use of animal sera, the development of a strategy for the ex vivo expansion of hMDPCs is required. The purpose of this study was to investigate the efficacy of using platelet-rich plasma (PRP) for the ex-vivo expansion of hMDPCs. Pre-plated MDPCs, myoendothelial cells, and pericytes are three populations of hMDPCs that we isolated by the modified pre-plate technique and Fluorescence Activated Cell Sorting (FACS), respectively. Pooled allogeneic human PRP was obtained from a local blood bank, and the effect that thrombin-activated PRP-releasate supplemented media had on the ex-vivo expansion of the hMDPCs was tested against FBS supplemented media, both in vitro and in vivo. PRP significantly enhanced short and long-term cell proliferation, with or without FBS supplementation. Antibody-neutralization of PDGF significantly blocked the mitogenic/proliferative effects that PRP had on the hMDPCs. A more stable and sustained expression of markers associated with stemness, and a decreased expression of lineage specific markers was observed in the PRP-expanded cells when compared with the FBS-expanded cells. The in vitro osteogenic, chondrogenic, and myogenic differentiation capacities of the hMDPCs were not altered when expanded in media supplemented with PRP. All populations of hMDPCs that were expanded in PRP supplemented media retained their ability to regenerate myofibers in vivo. Our data demonstrated that PRP promoted the proliferation and maintained the multi-differentiation capacities of the hMDPCs during ex-vivo expansion by maintaining the cells in an undifferentiated state. Moreover, PDGF appears to be a key contributing factor to the beneficial effect that PRP has on the proliferation of hMDPCs. © 2013 Li et al

    Grain-Size Distribution of Surface Sediments in the Chanthaburi Coast, Thailand and Implications for the Sedimentary Dynamic Environment

    No full text
    This paper analyzes the grain-size distribution of surface sediments of the Chanthaburi coast of Thailand to investigate the sedimentary environment and its evolution to better use and protect the coast. The Flemming triangle method, the grade-standard deviation method, and the Gao–Collins grain-size trend analysis method (GSTA model) were used to study the dynamic sedimentary environment of the area and provide preliminary identification of source materials. There are seven types of surface sediments on this coast, with grain sizes (φ) generally consisting of sand and silt. Sorting is generally poor, and becomes gradually poorer with distance offshore. Skewness is generally positive. The study area is mainly composed of sand and silt, indicating that the hydrodynamics are strong. The results of grade-standard deviation analysis indicate that sediment grain size b (3.25–4.5φ) is a sensitive indicator of environmental change. This sediment type exhibits a relatively complex transport trend, mainly characterized by northwestward and northeastward transport from sea to land. Sediments at the mouth of the Chanthaburi Estuary and the Welu River fluctuate under the influence of tidal currents. Based on the results of grade-standard deviation analysis and grain-size trend analysis, the study area was divided into three provinces, representing different sedimentary environments and material sources. Compared with tidal-controlled estuaries in the temperate regions of eastern China, the two tropical estuaries examined in this study exhibited smaller suspended sediment loads, runoff amounts, and tidal ranges. However, hydrodynamic conditions were generally stronger. The main reasons for the similarities and differences in the transport trends of sediments in these estuaries were differences in hydrodynamic conditions and the specifics of regional topography

    Deep Desulfurization of Diesel Oil with Extraction Using Pyridinium-Based Ionic Liquids

    No full text
    The pyridinium-based ionic liquids (ILs) 1-butyl-3,5-dimethylpyridinium tetrafluoroborate [((C4DMPy)-D-3,5][BF4]), 1-hexyl-3,5-dimethylpyridinium tetrafluoroborate [((C6DMPy)-D-3,5][BF4]) and, 1-octyl-3,5-dimethylpyridinium tetrafluoroborate [((C8DMPy)-D-3,5] [BF4]) were found to be effective for the selective removal of aromatic heterocyclic sulfur compounds from diesel. The results suggested that the structure and size of the cation greatly affect the extractive performance of ILs. For each sulfur compound studied here (4,6-Dimethyldibenzothiophene (4,6-DMDBT), dibenzothiophene (DBT), benzothiophene (BT), and thiophene (TS)), the extractive performance using pyridinium-based ILs followed the order of [C4Py][BF4] < [C6Py][BF4] < [C8Py][BF4] < [(C4MPy)-M-3] [BF4] < [(C4DMPy)-D-3,5][BF4] < [(C6MPy)-M-3][BF4] < [(C8MPy)-M-3][BF4] < [(C6DMPy)-D-3, 5][BF4] < [(C8DMPy)-D-3,5][BF4]. In addition, the pyridinium-based ILs would not contaminate the diesel due to their insolubility. On the other hand, diesel has a certain solubility in pyridinium-based ILs, varying from 0.49 wt% for [C4Py][BF4] to 19.6 wt% for [(C8DMPy)-D-3,5][BF4]. Considering these results, ILs studied in this work are more competitive and feasible for extractive desulfurization applications. Moreover, the extractive desulfurization using pyridinium-based ILs could be used at least as a complementary process to hydrodesulfurization (HDS)

    Electrophoretic deposition of metal oxide films aimed for gas sensors application: The role of anodic aluminum oxide (AAO)/Al composite structure

    No full text
    Anodic aluminum oxide (AAC)/Al composite structure was prepared and used to fabricate metal oxide gas sensing film through electrophoretic deposition (EPD) process, and Ga-doped ZnO (GZO) and GZO post-treated in H(2) (GZO-H) were used as high resistance and low resistance metal oxide models. The results showed that, in EPD process, Al (residual All after anodic oxidation) plays as the electrode with the electric field penetrating the pores of AAO. And dispersant Such as alcohols were preferred as H(2) would be produced on the AAO/Al electrode in aqueous dispersion, which destroyed both the AAO layer and the GZO (or GZO-H) him. While in the gas sensing process, AAO (AAO layer) plays as the insulative layer between GZO (or GZO-H) film and Al Substrate. The thickness of AAO layer should be properly tailored (i.e. >80 mu m) as to make its resistance far larger than that of the GZO film, which prevents the current leakage from the GZO film to the Al substrate. While the thickness can be 10 mu m when GZO-H film was used as its resistance is smaller. The AAO/Al composite structure made the EPD process feasible for gas sensing film fabrication, without any further treatment, which showed prospect in fabrication of metal oxide semiconductor gas sensors. (C) 2009 Elsevier B.V. All rights reserved

    Extraction and oxidative desulfurization of diesel fuel catalyzed by a Bronsted acidic ionic liquid at room temperature

    No full text
    The Bronsted acidic ionic liquids 1-butyl-3-methylimidazolium hydrogen sulfate ([BMIM][HSO(4)]) and N-butylpyridinium hydrogen sulfate ([C(4)Py][HSO(4)]) were used as extractant and catalyst for desulfurization of diesel. The results show that [BMIM][HSO(4)] is better as extractant and catalyst than [C(4)Py][HSO(4)] during the desulfurization process. The sulfur removal of dibenzothiophene (DBT) in n-octane was 99.6% in 90 min under the conditions of V(model oil)/V(IL) = 2 : 1 and H(2)O(2)/DBT molar ratio at 5 (O/S = 5), at room temperature. The sulfur removal of four sulfur compounds by extraction and catalytic oxidation process followed the order of DBT > benzothiophene (BT) > thiophene (TS) > 4,6-dimethyldibenzothiophene (4,6-DMDBT). Moreover, the [BMIM][HSO(4)] can be recycled for at least 6 times with a little decrease in the desulfurization activity. The sulfur removal of diesel fuel containing sulfur content of 97 ppm is 85.5%, which was much better than desulfurization performance by simple extraction with IL (11.0%). In this extraction and oxidative desulfurization process, DBT was oxidized to corresponding sulfone by H(2)O(2) with Bronsted acidic IL [BMIM][HSO(4)] which served as not only extractant but also catalyst

    Facile Synthesis of Gold-nanoparticles-decorated Polymer Assemblies and Core-Shell Gold Nanoparticles Using Pluronic Block Copolymers

    No full text
    Synthesis of gold nanoparticles (AuNPs) and Pluronic triblock copolymer composite in aqueous medium was studied. Gold-polymer nanocomposite with different structures was fabricated by tailoring the molar ratio of gold precursors to Pluronic P123 molecules or pH value of the P123 solution. When a lower volume ratio of AuC14-/P123 (0.05) was employed at pH 11.1, a nanostmcture similar to plum pudding was obtained. AuNPs with an average diameter of 13.1 nm were embedded in Pluronic assemblies, and each one held about 21 single gold nanoparticles. When AuCln-/P123 was increased to 0.1, core-shell structure was obtained if the pH value was in the range of 10.6-11.6, while gold polyhedra were fabricated when pH value was 8.1. Typical core-shell AuNPs had an average diameter of 9.6 nm with a narrow size distribution, while gold polyhedras with a mean diameter of 12.8 nm was obtained. The specific morphologies of the resultant nanocomposite were presumably obtained due to the synergistic interaction among the reactants
    • …
    corecore