Scanning Stage Research Articles

Analysis of micro-structural damage evolution of concrete through coupled X-ray computed tomography and gray-level co-occurrence matrices method

Concrete CT test is an effective method used to analyze micro-structural damage evolution of concrete under loading condition. In the CT images of different stress states in the same section, gray value changes in the original number matrix of CT image are the key to investigate microscopic damage evolution of concrete. However, the slight changes in the gray value of CT images before peak stress cannot be intuitively observed with the naked eye. This study mainly aims to develop a coupled method based on statistical method and X-ray CT to extract indicators of such subtle changes. Different cross-sectional CT images of concrete at different stress stages were obtained by uniaxial static compression CT test. The theory of the grey level co-occurrence matrices (GLCM) was then adopted to analyze micro-damage evolution and crack properties. That is, the GLCM of the CT images were calculated, and four statistical features including contrast, energy, correlation, and homogeneity were extracted, which can be extended into quantitative analysis of micro-damage hidden in the CT images of concrete. Results exhibited that the damage growth area, concentrating between the 45th and 225th concrete cross-section, could be predicted by the distribution of four statistical features (i.e., contrast, energy, correlation and homogeneity) at the fourth scan, and it is consistent with the crack location in the fifth scan. The contrast, energy and homogeneity follow the Gaussian distribution under five scan stages, and the correlation follows the Laplace distribution. In addition, the changes of bandwidth in color heat map illustrating the GLCM before and after specimen failure show that the bandwidth is positively correlated with micro-structural damage of concrete specimen.

Spectral response mapping of co-sensitized dye-sensitized solar cells dyed processed using rapid adsorption/desorption

Two-dimensional spectral response distribution maps in dye-sensitized solar cells (DSSC) are reported using 1 × 1 mm pixels for 0.5 × 2 cm DSSC devices by coupling external quantum efficiency (EQE) measurements with an X-Y scanning stage. The technique has been applied to singly dyed (D149 and N719) and co-sensitized (N719/SQ1 and D149/SQ1) devices. Dye desorption and re-dyeing processes have also been successfully mapped using this technique to help understand dye loading and dye location in multiply-sensitized cells.

A novel reconstruction method for on-machine measurement of parallel profiles with a four-probe scanning system

We present a four-probe scanning system to reconstruct a pair of parallel profiles which are the foundation of the straightness and parallelism measurement. The system, which is placed between two profiles to be measured and mainly used for on-machine measurement, consists of four displacement sensors. As the scanning stage moves along the profiles, the sensors collect measurement data of both profiles simultaneously. The reconstruction result is obtained by a double differential and a double integral, and the data processing eliminates the influence of the stage motion errors during the scanning. It is known that the zero-adjustment error of three sensors placed abreast in the system causes a parabolic reconstruction error, which can be removed by rotating the device 180° for a second scanning. Using the measurement data of the two scannings, straightness error and yaw error of the scanning motion, as well as the zero-adjustment error can be removed, and the reconstruction result can be utilized to evaluate straightness. In addition, the relative position of two measured profiles can also be calculated, which means the reconstruction result can be used to evaluate the parallelism of them. The new method possesses these following advantages: (i) reconstruction result is affected by neither motion error of the scanning stage nor the zero-adjustment error of sensors, (ii) reconstruction result can be utilized to evaluate both straightness and parallelism of the measured profiles, (iii) zero calibration of sensors is not required. The effectiveness and advantages of this method are demonstrated by theoretical analyses and simulations. And an experimental system was constructed to confirm its ability to eliminate errors.

Design, Modeling and Analysis of a XY Nanopositioning Stage for High Speed Scanning

In order to increase the imaging speed of scanning probe microscopy (SPM), especially atomic force microscopy (AFM) where needs a high-bandwidth moving stage possessing high resonant frequency and low cross-coupling, the paper proposes a kind of XY nanopositioning stage achieving about 10kHz resonant frequency, 15um×15um workspace and well decoupled performance. Considering the design objective, a compliant nanopositioning stage is built with doubly clamped beam and parallelogram hybrid beam for overcoming the problem of low natural frequency and cross-coupling performance. By establishing mathematical model of the proposed stage including stiffness model and resonant frequencies model, the paper solves the highest natural frequency with its optimal dimensions of beams by applying optimization. Finally the designed stage is imported to Workbench for the validation of mathematical model by simulation, where presents the FEA results can nicely match the analytical results.

Multifocus HDR VIS/NIR hyperspectral imaging and its application to works of art.

This paper presents a complete framework for capturing and processing hyperspectral reflectance images of artworks in situ, using a hyperspectral line scanner. These capturing systems are commonly used in laboratory conditions synchronized with scanning stages specifically designed for planar surfaces. However, when the intended application domain does not allow for image capture in these controlled conditions, achieving useful spectral reflectance image data can be a very challenging task (due to uncontrolled illumination, high-dynamic range (HDR) conditions in the scene, and the influence of chromatic aberration on the image quality, among other factors). We show, for the first time, all the necessary steps in the image capturing and post-processing in order to obtain high-quality HDR-based reflectance in the visible and near infrared, directly from the data captured by using a hyperspectral line scanner coupled to a rotating tripod. Our results show that the proposed method outperforms the normal capturing process in terms of dynamic range, color and spectral accuracy. To demonstrate the potential interest of this processing strategy for on-site analysis of artworks, we applied it to the study of a vintage copy of the famous painting "Transfiguration" by Raphael, as well as a facsimile of "The Golden Haggadah" from the British Library of London. The second piece has been studied for the identification of highly reflective gold-foil covered areas.

516 - Validation of strategies for selective bone scan staging in australian men with newly diagnosed prostate cancer

516 - Validation of strategies for selective bone scan staging in australian men with newly diagnosed prostate cancer

Application of adaptie statistical iterative reconstruction technology combined with low tube voltage in three phase enhanced low dose liver scanning

Objective: To explore the application value of adaptive statistical iterative reconstruction (ASIR) combined with low tube voltage in three-stage enhanced low-dose scan of liver. Methods: From March 2017 to November 2017, two groups which each group included 50 patients were randomly selected at the Second Affiliated Hospital of Harbin Medical University with different stages of arterial phase, delayed phase and portal vein scanning. GE Discovery CT 750 HD Liver CT Ⅲ was used during enhanced scanning. A total of 100 patients included 56 males and 44 females, aged 27-73 years old and 42 patients with hepatocellular carcinoma, 44 patients with hepatic hemangioma, and 14 patients with other diseases. The arterial and delayed period of group A patients were scanned with a low dose of 100 kV+ASIR, and the portal vein phase was conventional. Dosage scanning was 120 kV+FPP; the arterial and delayed period of group B was normal dose scanning, 120 kV+FPP, and the portal vein phase was low dose scanning, 100 kV+ASIR. At the same time, FBP reconstruction was used for all low-dose scanning phases to obtain low-dose images under normal reconstruction mode. The objective evaluation index of image quality was analyzed by completely randomized design analysis of variance, and Dunnett-t test was used to compare the two groups. For the subjective evaluation part, the rank sum test of multiple groups was used. Results: ASIR combined with low tube voltage enhanced low dose scanning in the third phase of the liver, and the radiation dose decreased by 37% in the low dose group compared with the normal dose group. There was no statistically significant difference between the low dose group (100 kV+ASIR) and the normal dose group (120 kV+FPP) in subjective image quality evaluation (P>0.05); objective evaluation of image quality except for low dose(100 kV+ASIR) portal stage noise slightly worse than conventional dose group (120 kV+FBP) (low dose 10.86±1.98, conventional dose 9.40±2.12, P<0.05), the other indexes in each period were superior or indifferent to the normal dose group. Conclusion: ASIR technique combined with low tube voltage can be used in the third phase of liver enhanced low-dose scanning and the image quality is improved.

Impact of CT-scan on evaluation of tumor spread in patients with nasopharyngeal carcinoma.

Background: Nasopharyngeal carcinoma, the most common neoplasm to arise in the nasopharynx, is a locally aggressive tumor with a high incidence of cervical nodal metastases. This study aimed to investigate the role of computed tomography in the evaluation of tumor stage (T stage) and nodal stage (N stage) in patients with nasopharyngeal carcinoma. Methods: CT scans of 338 newly diagnosed nasopharyngeal carcinoma patients were reviewed. All patients were restaged according to the 8th edition of the Union for International Cancer Control/ American Joint Committee on Cancer staging system relies on evaluation of the primary tumor (T category), the draining nodal groups (N category). Results: The 338 patients included in this analysis comprised 92 men and 246 women with a median age at diagnosis of 49 years (range, 10-89 years). WHO histopathologic type of non-ker?tinizing undifferentiated c?rcinom? was accounted 281/338 (83.1%), non-ker?tinizing differenti?ted c?rcinom? was 15.1%, and keratinizing squ?mous cell c?rcinom? was 1.8%. With CT scan staging, the proportions of T1, T2, T3 and T4 were 8.9% (30/338), 17.7% (60/338), 32.8% (111/338) and 40.5% (137/338), respectively; the proportions of N0, N1, N2 and N3 were 12.7% (43/338), 31.9% (108/338), 45.0% (152/338), and 10.4% (35/338), respectively. Conclusion: Computed tomography is essential for detection of early NPC, staging of the primary tumor, and evaluation of associated local lymphadenopathy.

Non-specific impairment of Lung Function on Spirometery in Patients with Chronic Hepatitis-C.

Objectives:To document frequency of non-specific impairment of lung functions (NILF) in patients of HCV and to compare according to gender, genotype, liver fibrosis score and smoking status.Methods:Patients of chronic hepatitis C were included after informed consent. Demographic data was recorded, and they underwent baseline investigations, fibroscan, abdominal ultrasound and PFT. Patients were segregated on basis of gender, fibroscan stages and smoking status. NILF was labelled if any two of three criteria are fulfilled (a) FVC < 80% of Predicted, (b) FEV1 < 80% Predicted, (c) FEV1/FVC ≥ 70.Results:Two hundred thirty four patients were of chronic HCV who fulfilled the selection criteria were inducted in study. These included 49.6% males and 50.4% females. There were 15.0% smokers, 16.2% were ex-smokers while 68.8% were never smokers. NILF was present in 130 (55.6%) out of which 61.5% were female and 38.5% were male (p <0.001), its presence in smokers was 56.2% and in never smokers was 55.3% (p=0.507). Presence of NILF increased with Fibroscan stages from F1 to F4 (p <0.001).Conclusions:NILF pattern on spirometry with normal chest radiograph is common among HCV patients. It was found more common in females and frequency increased progressively with fibro scan stages.

Adaptive Single-Mode Fiber Coupling Method Based on Coarse-Fine Laser Nutation

One of the major restrictions of the free-space optical communication systems is the limitation of single-mode fiber (SMF) coupling efficiency that impacts the system performance. In this paper, an adaptive coupling method for optical communication system based on coarse-fine laser nutation technique was presented. The scanning strategy and algorithm were set up and experimentally examined. The experimental results demonstrate that the coarse-fine laser nutation technique is capable of achieving a good coupling efficiency even the beam spot and the SMF do not coincide with each other at the start. The SMF center calculation accuracy of coarse and fine scanning stage were 0.25 and 0.01 μ m, respectively. And the average coupling efficiency of the system can increase from 0.351 in open loop to 0.624 in closed loop under a simulated atmospheric turbulence condition, the offset compensation error was 0.1245 μ m when turbulence induced. Finally, some factors influencing the systems were also discussed.

Toward Automated Identification of Glycan Branching Patterns Using Multistage Mass Spectrometry with Intelligent Precursor Selection.

Glycans play important roles in a variety of biological processes. Their activities are closely related to the fine details of their structures. Unlike the simple linear chains of proteins, branching is a unique feature of glycan structures, making their identification extremely challenging. Multistage mass spectrometry (MS n) has become the primary method for glycan structural identification. The major difficulty for MS n is the selection of fragment ions as precursors for the next stage of scanning. Widely used strategies are either manual selection by experienced experts, which requires considerable expertise and time, or simply selecting the most intense peaks by which the product-ion spectrum generated may not be structurally informative and therefore fail to make the assignment. We here report a glycan "intelligent precursor selection" strategy (GIPS) to guide MS n experiments. Our approach consists of two key elements, an empirical model to calculate candidate glycan's probability and a statistical model to calculate fragment ion's distinguishing power in order to select the structurally most informative peak as the precursor for next-stage scanning. Using 15 glycan standards, including three pairs with isomeric sequences and eight variously fucosylated oligosaccharides on linear or branched hexasaccharide backbones isolated from a human milk oligosaccharide fraction by HPLC, we demonstrate its successful application to branching pattern analysis with improved efficiency and sensitivity and also the potential for automated operation.

Implementation of 16-Channel AMR Sensor Array for Quantitative Mapping of Two-Dimension Current Distribution

Implementation of 16-Channel AMR Sensor Array for Quantitative Mapping of Two-Dimension Current Distribution

Automated image mapping and quantification of microstructure heterogeneity in additive manufactured Ti6Al4V

In Additive Manufacturing AM, each volume of material experiences a complex thermal history due to both short-range effects, from the repeated overlap of the thermal field from each heat source pass, and long-range variation in the thermal boundary conditions, related to the part geometry and build height. With an α + β alloy, like Ti64, this can lead to significant local variation in the transformation microstructure, which can contribute to heterogeneity in the mechanical properties of a component. In order to better understand the transformation microstructure variability in AM parts, an automated microstructure analysis tool has been developed, and tested against independently measured data, that can accurately map the inter-lamellar spacing of the α phase and spheroidicity of the β phase, at both high resolution and over large distances. The approach used was based on automated batch image analysis of thousands of image tiles obtained using a mapping function in a high-resolution SEM with a scanning stage. Within a practical operating range of drift in the microscope parameters (e.g. working distance, detector contrast) the errors in the measurements were found to be minimal (<3%). Results are discussed from applying the method to two example case studies from different ends of the AM spectrum; selective Electron Beam Melting (EBM) and Wire-Arc Additive Manufactured (WAAM). In the former case this revealed considerable drift in the microstructure with build height and geometry, but little short-range variation, whereas with the WAAM process more severe short range microstructural gradients associated with HAZ banding were fully quantified.

Automatic Raman spectroscopic urine crystal identification system using fluorescent image‐guided 2D scanning platform with Fe3O4 crystal violet nanoclusters

AbstractUrolithiasis is a common urological disease with a very high recurrence rate, within 5 years. Urine stones are formed by urine crystals. Although the relationship between the composition of the urine stone and the type of urine crystal has been recognized, the efficient collection and accurate identification of the type of urine crystal in clinics remains a challenge. In this study, we develop an automatic Raman spectroscopic urine crystal collection and identification system. Custom‐developed Fe3O4 crystal violet nanoclusters are used for (a) separating the urine crystals from the urine samples by a custom‐developed urine processing system and for (b) fluorescent labeling, image guiding, and the Raman spectroscopic measurement of the urine crystals on a 2D scanning stage. The control of the system and the Raman spectroscopic analysis are developed in a LabVIEW environment. This system is a fast and convenient method for the efficient collection and analysis of urinary crystals from urine samples, within 9 min. This automatic urine crystal identification system can enable the early prediction of the types of urine stones and the diet management for urolithiasis patients.

163Ho distillation and implantation for the HOLMES experiment

The HOLMES experiment aims to directly measure the ν mass with a calorimetric approach. The choice of 163Ho isotope as source is driven by the very low decay Q-value (∼ 2.8 keV), which allows for high sensitivity with low activities (O(102)Hz/detector), thus reducing the pile-up probability. 163Ho will be produced by neutron irradiation of 162Er2O3 then chemically separated; anyway, traces of others isotopes and contaminants will be still present. In particular 166mHo has a beta decay (τ∼1200y) which can induce background below 5 keV. The removal of the contaminants is critical so a dedicated system has been set up. It is designed to achieve an optimal mass separation @ 163 a.m.u. and consists of two main components: an evaporation chamber and an ion implanter. The first item is used to reduce Ho in metallic form providing a target for the ion implanter source. The implanter is made by the sputter source, an acceleration section, a magnetic dipole, a x–y scanning stage and a focusing electrostatic triplet. In this contribution we will describe the procedures for the Holmium “distillation” process and the status of the machine commissioning.

$$^{163}$$ 163 Ho Distillation and Implantation for HOLMES Experiment

HOLMES is an experiment to directly measure the neutrino mass with a calorimetric approach. The calorimetric technique eliminates several systematic uncertainties usually present in spectrometers where the external source and decays to excited states affect the measurement. \(^{163}\hbox {Ho}\) is chosen as source for its very low Q value (2.8 keV), the proximity of the end-point to resonance M1 and its half life (4570 year). These features are optimal to reach simultaneously a reasonable activity to have sufficient statistics in the end-point and a small quantity of \(^{163}\hbox {Ho}\) embedded in the detector not to alter significantly its heat capacity. \(^{163}\hbox {Ho}\) will be produced via neutron irradiation of enriched \(^{162}\hbox {Er}_{2}\hbox {O}_{3}\) at the Institute Laue–Langevin (Grenoble, France), and chemically separated at Paul Scherrer Institut (Villigen, Switzerland). It will arrive at INFN laboratory of Genova in oxide form (\(\hbox {Ho}_{2}\hbox {O}_{3}\)) with traces of others Ho isotopes and contaminants not removable using chemical methods. In particular, the metastable \(^{166\hbox {m}}\hbox {Ho}\) undergoes beta decay with a half life of about 1200 year, if present \(^{166\hbox {m}}\hbox {Ho}\) induces background below 5 keV. The removal of these contaminants is critical for HOLMES so a dedicated system is being set up. The system is designed to achieve an optimal mass separation for \(^{163}\hbox {Ho}\) and consists of two main components: an evaporation chamber and an ion implanter. In the evaporation chamber, holmium will be reduced in metallic form, using the reaction \(\hbox {2Y+Ho}_{2}\hbox {O}_{3}\rightarrow \)\(\hbox {Y}_{2}\hbox {O}_{3}\hbox {+2Ho}\) and used to produce a metallic target for the ion implanter source. The ion implanter consists of five main components: a Penning sputter ion source, an acceleration section, a magnetic/electrostatic mass analyser, a magnetic scanning stage and a focusing electrostatic triplet. In this contribution, we describe the procedures, under continuous refinement, for the holmium evaporation process, the ion-implanted metallic target production and the status of the ion implanter.

Absolute profile test by multi-sensor scanning system with relative angle measurement

In this paper, we present a novel method using an interferometer as a multi-sensor for an absolute profile test. Different from the traditional three flat test, which is complex to implement, the configuration of our method is similar to a classical sub-aperture stitching test but double scanning with different intervals is required. An additional interferometer or auto-collimator is used to measure relative tilt during scanning. The method we propose can eliminate not only systematic error in the interferometer but also the height offset error of the scanning stage, and it can achieve high lateral resolution. We analyze the effect of tilt estimation error on reconstruction accuracy and then propose a way to reduce its effect. The simulation results indicate our method can get exact results when free of noise. Comparisons are made between our method and the previously proposed sub-profile stitching method. The experiment results show that high repeatability and high accuracy can be reached in our method.

Auto-alignment of X-ray focusing mirrors with speckle-based at-wavelength metrology.

Significant improvements have been made in the fabrication of diffraction-limited X-ray optics used to pursue an aberration-free wavefront. Alignment of these optics plays a crucial role in the resultant beam quality. Here, we present a simple and fast alignment method based on imaging X-ray near-field speckle patterns, with experimental demonstration using a pair of Kirkpatrick-Baez mirrors. The proposed technique has the potential to be an alternative to conventional methods. It loosens the stringent demand for high-resolution scanning stages compared to conventional knife-edge scan and, hence, can be applied to nano-focusing optics. The flexibility and straightforward implementation of the method allow it to be applied to a wide range of experiments at synchrotron facilities and laboratory-based sources.

Performance Analysis of LCL-T Filter Based 2 Stage Single Phase Gird Connected Module with ANN Controller using PV Panel

Background: The whole thought is to demonstrate the parallel parking framework for self-ruling robots with the help of real-time embedded boards. Autonomous systems are outlined and developed by considering the non-holonomic requirements. PID controller is used to accomplish the servo reaction. The path planning scheme is created for parallel stopping of self-ruling vehicles by gaining data from the sensor. Methods: The three vital stages engaged in safety parking are scanning, positioning and maneuvering. The scanning stage filters the stopping condition by ultrasonic separation estimating sensors. The positioning stage advances the vehicle and in reverse. It is mostly used to alter the appropriate separation from the begin point to turn point before moving. The parallel stopping of self-ruling robots with non-holonomic requirements are mimicked through MATLAB environment and prototype implementation is carried out through embedded platform. Results: Initially, open loop response of the non-holonomic vehicle is unstable and nonlinear in nature. Therefore the PID controller is used to control the response of the non-holonomic vehicle with minimum error based on the set point. The goal of this research is to attain the parallel parking scheme for non-holonomic vehicles, which is attained with the help of real time implementation. This implementation has been carried out using embedded processor with PID algorithm, sensors and actuators. Conclusion: Hence the paper depicts the structure of non-holonomic robotic vehicle and control with the help of PID controller. The parallel parking scheme has established using MATLAB programming and verified with the help of real time prototype. The paper proposed an idea of automated parking system in contrast to manual parking by the driver. The consumption of space, energy and time are minimized due to the automated parking scheme. Due to human error and negligence, harms such as collisions and accidents are occurred. These harms are reduced by implementing the parallel parking scheme in an intelligent manner. In future, Fuzzy based PD controller will be developed and implemented for the enhancement of parallel parking algorithm in robots. Keywords: Grid Connected Inverter, LCL-T Filter, ANN Controller, MATLAB, State Space Equation.

Rationalising Skeletal Bone Scan Staging in Prostate Cancer

Rationalising Skeletal Bone Scan Staging in Prostate Cancer