50 research outputs found

    Linear Relative Pose Estimation Founded on Pose-only Imaging Geometry

    Full text link
    How to efficiently and accurately handle image matching outliers is a critical issue in two-view relative estimation. The prevailing RANSAC method necessitates that the minimal point pairs be inliers. This paper introduces a linear relative pose estimation algorithm for n (n6( n \geq 6) point pairs, which is founded on the recent pose-only imaging geometry to filter out outliers by proper reweighting. The proposed algorithm is able to handle planar degenerate scenes, and enhance robustness and accuracy in the presence of a substantial ratio of outliers. Specifically, we embed the linear global translation (LiGT) constraint into the strategies of iteratively reweighted least-squares (IRLS) and RANSAC so as to realize robust outlier removal. Simulations and real tests of the Strecha dataset show that the proposed algorithm achieves relative rotation accuracy improvement of 2 \sim 10 times in face of as large as 80% outliers

    Application of Laparoscopy in Comprehensive Staging Operation of Ovarian Cancer Based on Electronic Medical Blockchain Technology

    No full text
    Ovarian cancer has always entangled most women. Studies have shown that the prevalence of ovarian cancer ranks third in female reproductive malignancies, and the mortality rate has always been the highest. The reason is mainly because the diagnosis and treatment of preovarian cancer has always been a big problem. However, the emergence of laparoscopy can well solve this problem, especially laparoscopy assisted by blockchain technology, which plays a huge role in the overall staging of ovarian cancer. This article proposes the application research of laparoscopy in the comprehensive staging of ovarian cancer based on electronic medical blockchain technology. First of all, this article uses the literature method to study the clinical characteristics and surgical classification of ovarian cancer, as well as the application status of blockchain technology and laparoscopic technology. Secondly, it designed an application experiment based on electronic medical blockchain technology to assist laparoscopy in the comprehensive staging of ovarian cancer and analyzed the comparison of the laparoscopic group and the control group in the comprehensive staging of ovarian cancer. The results of the study showed that the amount of bleeding in the laparoscopic group was 103.5 ml, while the amount of bleeding in the control group was 141.1 ml; the proportion of tertiary pain in the laparoscopic group was 11.37%, and the proportion of tertiary pain in the control group was 31.82%. From this, it can be seen that, in the comprehensive staging operation for ovarian cancer, the laparoscopic group has less intraoperative blood loss than the control group and lower pain, and the treatment effect is better

    The Microstructure and Mechanical Properties of Dual-Spot Laser Welded-Brazed Ti/Al Butt Joints with Different Groove Shapes

    No full text
    Laser welding-brazing was performed to join Ti and Al together. The dual-spot laser beam mode was selected as the heat source in this study. Ti-6Al-4V and 6061-T6 Al alloys were selected as the experimental materials. Al-12Si welding wire was selected as the filler material. The effect of groove shape on the weld appearance, microstructure, temperature field, and mechanical performance of Ti/Al welded-brazed butt joints was investigated. The interfacial intermetallic compound (IMC) layer at the Ti/Weld brazing interface was inhomogeneous in joints with I-shaped and Y-shaped grooves. In Ti/Al joints with V-shaped grooves, the homogeneity of temperature field and IMC layer was improved, and the maximum thickness difference of IMC layer was only 0.20 μm. Nano-sized granular Ti7Al5Si12, Ti5Si3, and Ti(Al,Si)3 constituted the IMCs. The tensile strength of Ti/Al joints with V-shaped grooves was the highest at 187 MPa. The fracture mode transformed from brittle fractures located in the IMC layer to ductile fractures located in the Al base metal, which could be attributed to the improvement of the IMC layer at the brazing interface

    Understanding the effect of moderate concentration SDS on CO2 hydrates growth in the presence of THF

    No full text
    Additives like Tetrahydrofuran (THF) and Sodium Dodecyl Sulfate (SDS) improve CO2 hydrates thermal stability and growth rate when used separately. It has been hypothesised that combining them could improve the kinetics of growth and the thermodynamic stability of CO2 hydrates. We exploit atomistic molecular dynamics simulation to investigate the combined impact of THF and SDS under different temperatures and concentrations. The simulation insights are verified experimentally using pendant drop tensiometry conducted at ambient pressures and high-pressure differential scanning calorimetry. Our simulations revealed that the combination of both additives is synergistic at low temperatures but antagonistic at temperatures above 274.1 K due to the aggregation SDS molecules induced by THF molecules. These aggregates effectively remove THF and CO2 from the hydrate-liquid interface, thereby reducing the driving force for hydrates growth. Experiments revealed that the critical micelle concentration of SDS in water decreases by 20% upon the addition of THF. Further experiments showed that only small amounts of SDS with THF is sufficient to increase the CO2 storage efficiency by over 40% compared to results obtained without promoters. These results provide microscopic insights into the mechanisms of THF and SDS promoters on CO2 hydrates, which allow for determining the optimal condition for hydrate growth

    Efficient In Vitro Propagation of <i>Turpinia arguta</i> and Quantitative Analysis of Its Ligustroflavone and Rhoifolin Content

    No full text
    Turpinia arguta is an excellent medicinal plant mainly used for the treatment of pharyngitis, tonsillitis, and tonsillar abscesses. However, an efficient regeneration protocol using tissue cultures for T. arguta does not exist. Its main medicinal constituents are flavonoids, particularly ligustroflavone and rhoifolin. Here, we aimed to establish a tissue culture system for T. arguta for the first time using annual stem segments with axillary buds harvested from the field of the Jiangxi Academy of Forestry as explants by dynamically determining the accumulation of effective functional components in the tissue culture plantlets. Orthogonal tests were conducted to compare the effects of different explant disinfection times, media, and exogenous hormone ratios on the induction of the axillary bud growth, successional proliferation, and rooting of T. arguta stem segments. The best explant disinfection effect was achieved by disinfecting the T. arguta explant with 75% ethanol for 50 s, followed by 0.1% mercuric chloride (HgCl2) for 6 min, and the optimal media for successional proliferation and rooting were Murashige and Skoog (MS) + 0.2 mg/L of 6-benzyladenine (6-BA), + 0.03 mg/L of naphthaleneacetic acid (NAA), and ½ MS + 2.5 mg/L of indole-3-butyric acid + 0.5 mg/L of NAA, respectively. The detection of ligustroflavone and rhoifolin in tissue culture plantlets 0, 3, and 5 months after transplanting showed a significant increasing trend and eventually exceeded the content requirements of the 2020 Edition ofChinese Pharmacopoeia for T. arguta. Our findings provide, for the first time, an effective tissue culture system for T. arguta, thereby providing important information to support the germplasm preservation, innovation, and application of T. arguta in the future

    Understanding the effect of moderate concentration SDS on CO2 hydrates growth in the presence of THF

    No full text
    Hypothesis: Additives like Tetrahydrofuran (THF) and Sodium Dodecylsulfate (SDS) improve Carbon Dioxide (CO2) hydrates thermal stability and growth rate when used separately. It has been hypothesised that combining them could improve the kinetics of growth and the thermodynamic stability of CO2 hydrates. // Simulations and Experiments: We exploit atomistic molecular dynamics simulations to investigate the combined impact of THF and SDS under different temperatures and concentrations. The simulation insights are verified experimentally using pendant drop tensiometry conducted at ambient pressures and high-pressure differential scanning calorimetry. // Findings: Our simulations revealed that the combination of both additives is synergistic at low temperatures but antagonistic at temperatures above 274.1 K due to the aggregation of SDS molecules induced by THF molecules. These aggregates effectively remove THF and CO2 from the hydrate-liquid interface, thereby reducing the driving force for hydrates growth. Experiments revealed that the critical micelle concentration of SDS in water decreases by 20% upon the addition of THF. Further experiments in the presence of THF showed that only small amounts of SDS are sufficient to increase the CO2 storage efficiency by over 40% compared to results obtained without promoters. Overall, our results provide microscopic insights into the mechanisms of THF and SDS promoters on CO2 hydrates, useful for determining the optimal conditions for hydrate growth
    corecore