405 research outputs found

    Soliton-potential interaction in the nonlinear Klein-Gordon model

    Full text link
    The interaction of solitons with external potentials in nonlinear Klein-Gordon field theory is investigated using an improved model. The presented model has been constructed with a better approximation for adding the potential to the Lagrangian through the metric of background space-time. The results of the model are compared with another model and the differences are discussed.Comment: 14 pages,8 figure

    Collective-coordinate analysis of inhomogeneous nonlinear Klein-Gordon field theory

    Full text link
    Two different sets of collective-coordinate equations for solitary solutions of Nonlinear Klein-Gordon (NKG) model is introduced. The collective-coordinate equations are derived using different approaches for adding the inhomogeneities as exrernal potentials to the soliton equation of motion. Interaction of the NKG field with a local inhomogeneity like a delta function potential wall and also delta function potential well is investigated using the presented collective-coordinate equations and the results of two different models are compared. Most of the characters of the interaction are derived analytically. Analytical results are also compared with the results of numerical simulations.Comment: 16 pages, 8 figures. Accepted for publication in Volume 43 of the Brazilian Journal of Physic

    Embedding Radars in Robots for Safety and Obstacle Detection

    Get PDF
    A safety system is designed to use small, low-cost radars embedded in joints and end effectors of a robot to monitor an environment for potential safety hazards. In this way, the radars directly detect obstacles with respect to the moving parts of the robot. A safety controller analyzes the obstacle data provided by the radars and determines an appropriate operating state of the robot based on predefined safety requirements

    Embedding Radars in Robots to Accurately Measure Motion

    Get PDF
    A motion correction system is designed to use small, low-cost radars embedded in joints and end effectors of a robot to measure motion of the robot. In this way, the radars directly measure the robot’s motion and relative position and velocity with respect to a target. A motion correction controller analyzes the motion data provided by the radars and determines an amount of motion correction required to accurately position the robot

    Closed-Loop Manufacturing System Using Radar

    Get PDF
    A closed-loop manufacturing system is designed to use small, low-cost radar to observe a manufacturing process and measure characteristics of a build product. The build data measured by the radar includes geometry, reflection characteristics, material density, and high resolution maps. A controller processes the build data to detect errors. Example errors include mistakes in geometry, delamination, curling, shrinkage, lack of material uniformity, air bubbles, inclusions, and contaminations in the build product. Based on the detected errors, the controller determines build corrections and reports the build corrections to the manufacturing process. Using radar, the closed-loop manufacturing system automatically detects and corrects errors, saving time and resources in additive and subtractive manufacturing

    Safety and efficacy of PDpoetin for management of anemia in patients with end stage renal disease on maintenance hemodialysis: Results from a phase IV clinical trial

    Get PDF
    Recombinant human erythropoietin (rHuEPO) is available for correcting anemia. PDpoetin, a new brand of rHuEPO, has been certified by Food and Drug Department of Ministry of Health and Medical Education of Iran for clinical use in patients with chronic kidney disease. We conducted this post-marketing survey to further evaluate the safety and efficacy of PDpoetin for management of anemia in patients on maintenance hemodialysis. Patients from 4 centers in Iran were enrolled for this multicenter, open-label, uncontrolled phase IV clinical trial. Changes in blood chemistry, hemoglobin and hematocrit levels, renal function, and other characteristics of the patients were recorded for 4 months; 501 of the patients recruited, completed this study. Mean age of the patients was 50.9 (±16.2) years. 48.7 of patients were female. Mean of the hemoglobin value in all of the 4 centers was 9.29 (±1.43) g/dL at beginning of the study and reached 10.96 (±2.23) g/dL after 4 months and showed significant increase overall (P<0.001). PDpoetin dose was stable at 50-100 U/kg thrice weekly. Hemorheologic disturbancesand changes in blood electrolytes was not observed. No case of immunological reactions to PDpoetin was observed. Our study, therefore, showed that PDpoetin has significantly raised the level of hemoglobin in the hemodialysis patients (about 1.7±0.6 g/dL). Anemia were successfully corrected in 49 of patients under study. Use of this biosimilar was shown to be safe and effective for the maintenance of hemoglobin in patients on maintenance hemodialysis. © A.N. Javidan et al., 2014

    Changes of Leptin concentration in plasma in patients with spinal cord injury: A Meta-analysis

    Get PDF
    Objective:The aim of this study was to investigate changes of leptin concentration in plasma in patients with spinal cord injury to come to a single concept by using a Meta-analysis.Setting:Systematic Review.Methods:Searching relevant articles was performed in Ovid data base, Medline (PubMed) EMBASE, Google Scholar, Cochrane and Scopus up to February 2013. Five articles were selected using two independent reviewers. Analysis were performed using SPSS version 18 and Comparative Meta-analysis software version 2.0.Results:The combined analysis with confidence interval of 95 using comprehensive meta-analysis showed significant higher leptin levels in patients with spinal cord injury in comparison with able bodies (P<0.0001). The effect of spinal lesion level on plasma leptin concentration was also statistically significant (P<0.0001). Body mass index was positively related to plasma leptin concentration in both groups (P<0.0001).Conclusion:This Meta analysis approves increased level of leptin in spinal cord injured patients which can be due to fat distribution changes and sympathetic dysfunction in these patients. Our results also showed that patients with higher spinal lesion level have higher plasma leptin concentration. © 2013 International Spinal Cord Society All rights reserved
    corecore