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Performance characterisation of a real-time fiber dosimetry system using radiophotoluminescent glasses
摘要： We report the first demonstration of a real-time fiber-optic-coupled dosimetry system using Ag-activated phosphate glasses based on radiophotoluminescent (RPL) phenomena. The performance characterisation using real-time fiber RPL glass dosimetry is compared with that of real-time fiber plastic scintillation dosimetry. The inevitable build-up phenomena occurring in Ag-activated RPL glasses both during and after X-ray exposure were measured. The real-time RPL curves for the X-ray exposure region and the build-up region are analytically evaluated and fitted to the second-order polynomial functions and the sum of three exponentials, respectively. In addition, some resolved problems of real-time fiber RPL glass dosimetry are discussed.
关键词： X-ray exposure,real-time fiber dosimetry,build-up phenomena,radiophotoluminescent glasses,Ag-activated phosphate glasses
更新于2025-09-09 09:28:46
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Image-based guidance of percutaneous abdomen intervention based on markers for semi-automatic rigid registration
摘要： Introduction: For percutaneous abdomen intervention (e.g. liver radiofrequency (RF) tumor ablation, liver biopsy), surgeons lack real-time visual feedback about the location of the needle on planning images, typically computed tomography (CT). One difficulty lies in tracking and synchronizing both the tool movement and the patient breathing motion. Aim: To verify the correspondence between rigid registration fiducial registration error signal and breathing phase. Material and methods: Designed markers that are clearly visible both in planning CT and on the patient during the intervention are proposed. Registration and breathing synchronization is then performed by a point-based approach. The method was tested in a clinical environment on 10 patients with liver cancer using 3D abdominal CT in the exhale position. Median rigid fiducial registration error (FRE) in the breathing cycle was used as a criterion to distinguish the inhale and exhale phase. Results: The correlation between breathing phase and FRE value can be observed for every patient. We obtained mean median FRE equal to 9.37 mm in exhale positions and 15.56 mm in the whole breathing cycle. Conclusions: The presented real time approach, based on FRE calculation, was integrated in the clinical pipeline, and can help to select the best respiratory phase for needle insertion for percutaneous abdomen intervention, in cases where only 3D CT is performed. Moreover, this method allows semi-automated rigid registration to establish the correspondence between preoperative patient anatomical model and patient position.
关键词： real-time rigid registration,percutaneous abdomen intervention,respiratory phase synchronization
更新于2025-09-09 09:28:46
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A simple amplitude decision based symbol timing synchronization method for real-time IMDD-OOFDM systems
摘要： A simple amplitude decision based symbol timing synchronization method for real-time IMDD-OOFDM transmission systems is proposed and experimentally evaluated by using directly modulated DFB laser in 25? km SSMF. The experimental results show that the hardware resource consumption of the proposed synchronization technique is only 6% of the total system which can effectively release the computation complexity without sacri- ficing the synchronization accuracy. Less than 2 samples offset error of synchronization accuracy can be achieved at received optical power as low as ? 20?dBm without employing correlation and multiplication operations.
关键词： Amplitude decision,Real-time optical system,Symbol timing synchronization,IMDD-OOFDM transmission system
更新于2025-09-09 09:28:46
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A real-time impact detection and diagnosis system of catenary using measured strains by fibre Bragg grating sensors
摘要： This paper describes an impact detection system using strain signals based on fibre optic sensors(FBG) for the real-time monitoring of the catenary system. The proposed detection system consists of three subsystems: a measuring system, a data processing and analysis system, and a status display and data access system. Because the strain signals obey the normal distribution, to monitor the catenary system in real time, a novel method that combines mobile standard deviation with the mobile Pauta criterion is proposed to distinguish real impact from the strain signal background. The use of this adaptive judging method reduces the misjudgment rate of impacts and improves the impact recognition accuracy. These impacts can be identified by the data analysis system, which provides impact location and their causes using the features of the catenary system. This method can simplify the detection system compared with the traditional location method. An application to a commercial metro line system indicated that the impacts on the catenary system were main caused by overlaps, expansion joints or steady arms, and were verified by correspondence with the floor plan of the catenary and manual inspection results. These results verified the reliability and effectiveness of the proposed impact detection system.
关键词： catenary,real-time monitoring,fibre Bragg grating,Impact detection,fault diagnosis
更新于2025-09-09 09:28:46
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[IEEE 2018 IEEE PES/IAS PowerAfrica - Cape Town, South Africa (2018.6.28-2018.6.29)] 2018 IEEE PES/IAS PowerAfrica - Impact of Solar Eclipse on Utility Grid Operations
摘要： Solar eclipse is viewed as a volatile meteorological condition in electric power grids with Photovoltaics (PV) penetration. The impact of the U.S. August 21, 2017 solar eclipse on control center operations associated with a large PV plant has been investigated and compared with normal day operations. The utility-scale PV plant simulated using a real-time digital simulator and receiving real-time weather data measurements from the weather monitoring station at Clemson University, South Carolina has been studied. The open challenge utilities are facing nowadays with increasing penetration of PV in the grid has been illustrated. The insights of this study can be used by utilities for planning and operational studies.
关键词： solar eclipse,automatic generation control,real-time grid operations,Area control error,photovoltaics
更新于2025-09-09 09:28:46
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[ASME ASME 2018 Conference on Smart Materials, Adaptive Structures and Intelligent Systems - San Antonio, Texas, USA (Monday 10 September 2018)] Volume 2: Mechanics and Behavior of Active Materials; Structural Health Monitoring; Bioinspired Smart Materials and Systems; Energy Harvesting; Emerging Technologies - Real-Time Detection of Ancient Architecture Features Based on Smartphones
摘要： Due to the particularity of texture features in ancient buildings, which refers to the fact that these features have a high historical and artistic value, it is of great significance to identify and count them. However, the complexity and large number of textures are a big challenge for the artificial identification statistics. In order to overcome these challenges, this paper proposes an approach that uses smartphones to achieve a real- time detection of ancient buildings’ features. The training process is based on SSD-Mobilenet, which is a kind of Convolutional Neural Network (CNN). The results show that this method shows well performance in reality and can indeed detect different ancient building features in real time.
关键词： real- time object detection,smartphone,ancient architecture feature,deep learning,convolution neural network,SSD-Mobilenet
更新于2025-09-04 15:30:14
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Adaptive filtering of physiological noises in fNIRS data
摘要： The study presents a recursive least?squares estimation method with an exponential forgetting factor for noise removal in functional near?infrared spectroscopy data and extraction of hemodynamic responses (HRs) from the measured data. The HR is modeled as a linear regression form in which the expected HR, the first and second derivatives of the expected HR, a short?separation measurement data, three physiological noises, and the baseline drift are included as components in the regression vector. The proposed method is applied to left?motor?cortex experiments on the right thumb and little finger movements in five healthy male participants. The algorithm is evaluated with respect to its performance improvement in terms of contrast?to?noise ratio in comparison with Kalman filter, low?pass filtering, and independent component method. The experimental results show that the proposed model achieves reductions of 77% and 99% in terms of the number of channels exhibiting higher contrast?to?noise ratios in oxy?hemoglobin and deoxy?hemoglobin, respectively. The approach is robust in obtaining consistent HR data. The proposed method is applied for both offline and online noise removal.
关键词： State space model,Hemodynamic response (HR),Exponential forgetting,Recursive least squares estimation (RLSE),Real time estimation,Functional near?infrared spectroscopy (fNIRS)
更新于2025-09-04 15:30:14
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Relationship between C=C double bond conversion and dissolution kinetics in cross-linking-type photoresists for display manufacture, studied by real-time Fourier transform infrared spectroscopy and quartz crystal microbalance methods
摘要： Photoresists are an indispensable technology used for manufacturing electronic devices such as displays and semiconductors. In this study, we investigated the relationship between C=C double bond conversion and dissolution kinetics in cross-linking-type photoresists used for display manufacture using real-time Fourier transform infrared spectroscopy (FTIR) and quartz crystal microbalance (QCM) methods. To improve photoresist performance, it is important to understand the development mechanism of photoresists. Two kinds of polymers (a polymer with peeling-type dissolution and a polymer with a dissolution type with Case II diffusion) were used. 1,2-Octanedione-1-[4-(phenylthio)-2-(O-benzoyloxime)] and bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide were used as photoinitiators. The dissolution was of the peeling type when the polymers were formulated as a typical cross-linking-type photoresist. With increasing conversion ratio of C=C double bonds, the rate of developer intake decreased and the impregnation threshold before the onset of peeling increased and then decreased. It was also found that the dissolution kinetics were affected by the radicals generated upon the decomposition of photoinitiators.
关键词： C=C double bond conversion,dissolution kinetics,quartz crystal microbalance,Photoresists,real-time Fourier transform infrared spectroscopy
更新于2025-09-04 15:30:14
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Improvement in infected wound healing in type 1 diabetic rat by the synergistic effect of photobiomodulation therapy and conditioned medium
摘要： We investigated the effects of photobiomodulation therapy (PBMT) and conditioned medium (CM) of human bone marrow mesenchymal stem cells (hBM‐MSC) individually and/or in combination on the stereological parameters and the expression of basic fibroblast growth factor (bFGF), hypoxia‐inducible factor (HIF‐1α), and stromal cell–derived factor‐1α (SDF‐1α) in a wound model infected with methicillin‐resistant Staphylococcus aureus (MRSA) in diabetic rats. CM was provided by culturing hBM‐MSCs. Type 1 diabetes mellitus (T1DM) was induced in 72 rats, divided into four groups, harboring 18 rats each: group 1 served as a control group, group 2 received PBMT, group 3 received CM, and group 4 received CM + PBMT. On days 4, 7, and 15, six animals from each group were euthanized and the skin samples were separated for stereology examination and gene expression analysis by real‐time polymerase chain reaction. In the CM + PBMT, CM, and PBMT groups, significant decreases were induced in the number of neutrophils (1460 ± 93, 1854 ± 138, 1719 ± 248) and macrophages (539 ± 69, 804 ± 63, 912 ± 41), and significant increases in the number of fibroblasts (1073 ± 116, 836 ± 75, 912 ± 41) and angiogenesis (15 230 ± 516, 13 318 ± 1116, 14 041 ± 867), compared with those of the control group (2690 ± 371, 1139 ± 145, 566 ± 90, 12 585 ± 1219). Interestingly, the findings of the stereological examination in the CM + PBMT group were statistically more significant than those in the other groups. In the PBMT group, in most cases, the expression of bFGF, HIF‐1α, and SDF‐1α, on day 4 (27.7 ± 0.14, 28.8 ± 0.52, 27.5 ± 0.54) and day 7 (26.8 ± 1.4, 29.6 ± 1.4, 28.3 ± 1.2) were more significant than those in the control (day 4, 19.3 ± 0.42, 25.5 ± 0.08, 22.6 ± 0.04; day 7, 22.3 ± 0.22, 28.3 ± 0.59, 24.3 ± 0.19) and other treatment groups. The application of PBMT + CM induced anti-inflammatory and angiogenic activities, and hastened wound healing process in a T1 DM model of MRSA infected wound.
关键词： stereology,diabetes mellitus,diabetic foot ulcer,methicillin‐resistant staphylococcal aureus,low‐level laser therapy,phobiomodulation therapy,human bone marrow mesenchymal stem cell‐conditioned medium,real‐time PCR,rat
更新于2025-09-04 15:30:14
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Formation and Evolution of Ultrathin Silica Polymorphs on Ru(0001) Studied with Combined in Situ, Real-Time Methods
摘要： Silica mono- and bilayer films on Ru(0001) can be physisorbed or chemisorbed, with ordered or vitreous structures, depending on the particular preparation procedures applied. Using the SMART spectro-microscope at BESSY-II with its capabilities for μ-spectroscopy, μ-diffraction, and LEEM imaging with lateral resolution below 5 nm, in situ and in real time and applied to identical areas, we have investigated the formation of these layers, defined and characterized their properties and their connected morphology, and followed their evolution. Two distinct chemisorbed monolayers and three bilayers (physisorbed crystalline and vitreous, and chemisorbed zigzag phases), and some transitions between them, have been studied. We found that, apart from the deposited silicon amount, the most important parameter for steering the evolution to a particular well-defined layer is the oxygen content at the Ru interface. Nucleation and growth of all layers are homogeneous on the scale of our resolution, leading to rather small domains (20 – 40 nm), mostly of the same phase, separated by defect lines. We discuss these and other basic findings in context and point out open questions. We also offer alternative recipes for the preparation of some phases, to obtain more homogeneous layers on a mesoscopic scale.
关键词： Silica films,SMART spectro-microscope,real-time methods,in situ,LEEM,chemisorbed,physisorbed,polymorphs,Ru(0001),μ-spectroscopy,μ-diffraction
更新于2025-09-04 15:30:14