2,984 research outputs found

    Feedback-Optimized Operations with Linear Ion Crystals

    Full text link
    We report on transport operations with linear crystals of 40Ca+ ions by applying complex electric time-dependent potentials. For their control we use the information obtained from the ions' fluorescence. We demonstrate that by means of this feedback technique, we can transport a predefined number of ions and also split and unify ion crystals. The feedback control allows for a robust scheme, compensating for experimental errors as it does not rely on a precisely known electrical modeling of the electric potentials in the ion trap beforehand. Our method allows us to generate a self-learning voltage ramp for the required process. With an experimental demonstration of a transport with more than 99.8 % success probability, this technique may facilitate the operation of a future ion based quantum processor

    Some solutions, some problems, and some questions

    Get PDF
    "December, 1981.""National Science Foundation ... Grant ECS-8012668"Alan S. Willsky

    Signal Formation Processes in Micromegas Detectors and Quality Control for large size Detector Construction for the ATLAS New Small Wheel

    Full text link
    The Micromegas technology is one of the most successful MPGD concepts and widely utilized in nuclear and particle physics experiments. Twenty years of research and development rendered the technology sufficiently mature to be selected as precision tracking detector for the New Small Wheel (NSW) upgrade of the ATLAS Muon spectrometer. This will be the first large scale application of Micromegas in one of the major LHC experiments. The studies on signal formation in Micromegas focuses on the microscopic signal electron loss mechanisms and the amplification processes in electron gas interaction. Based on a model of detector parameter dependencies, these processes are scrutinized in an iterating comparison between exper- imental results, theory prediction of the macroscopic observables and process simulation on the microscopic level. Utilizing the specialized detectors developed in the scope of this thesis as well as refined simulation algorithms, an unprecedented level of accuracy in the process description is reached, deepening the understanding of the fundamental process in gaseous detectors. The second part is dedicated to the challenges arising with the large scale Micro- megas production for the ATLAS NSW. A selection of technological choices, are discussed alongside a final report on two production related tasks addressing the detectors core components: For the industrial production of resistive anode PCBs a detailed quality control (QC) and quality assurance (QA) scheme as well as the therefore required testing tools have been developed. In parallel the study on micromesh parameter optimization and production feasibility resulted in the selection of the proposed mesh by the NSW community. The successful completion of both tasks were important milestones towards the construction of large size Micromegas detectors clearing the path for NSW series production.Comment: Version 2: Added reference for figure 6.8, subesequent reference numbers update

    Novel Approaches for Nondestructive Testing and Evaluation

    Get PDF
    Nondestructive testing and evaluation (NDT&E) is one of the most important techniques for determining the quality and safety of materials, components, devices, and structures. NDT&E technologies include ultrasonic testing (UT), magnetic particle testing (MT), magnetic flux leakage testing (MFLT), eddy current testing (ECT), radiation testing (RT), penetrant testing (PT), and visual testing (VT), and these are widely used throughout the modern industry. However, some NDT processes, such as those for cleaning specimens and removing paint, cause environmental pollution and must only be considered in limited environments (time, space, and sensor selection). Thus, NDT&E is classified as a typical 3D (dirty, dangerous, and difficult) job. In addition, NDT operators judge the presence of damage based on experience and subjective judgment, so in some cases, a flaw may not be detected during the test. Therefore, to obtain clearer test results, a means for the operator to determine flaws more easily should be provided. In addition, the test results should be organized systemically in order to identify the cause of the abnormality in the test specimen and to identify the progress of the damage quantitatively

    The formation of an infection-related membrane domain is controlled by the sequential recruitment of scaffold and receptor proteins

    Get PDF

    Texture and Colour in Image Analysis

    Get PDF
    Research in colour and texture has experienced major changes in the last few years. This book presents some recent advances in the field, specifically in the theory and applications of colour texture analysis. This volume also features benchmarks, comparative evaluations and reviews
    corecore