High Data Acquisition Rate Research Articles

Fast and robust demodulation of temperature from sparse sapphire fiber Bragg grating spectra with machine learning

Sapphire fiber Bragg gratings (FBGs) have demonstrated their efficacy in sensing at high-temperature harsh environments owing to their elevated melting point and outstanding stability. However, due to the extremely high volume of modes supported by the clad-less sapphire fiber, the demodulation capability of the reflected spectra is hindered due to their irregular and somewhat complicated shapes. Hence, a mode-stripping or scrambling step is typically employed beforehand, albeit at the expense of sensor robustness. Additionally, conventional interrogation of sapphire FBG sensors relies on an optical spectrum analyzer due to the high sensitivity provided by the spectrum analyzer, where the long data acquisition time restricts the system from detecting instantaneous temperature variations. In this study, we present a simple sensor configuration by directly butt-coupling the sapphire FBG multi-mode lead-out fiber to a single-mode lead-in fiber, and detect its reflected spectra via a low-cost, fast, and coarsely resolved (166 pm) spectrometer. We leverage machine learning to compensate for the under-sampling of the measured FBG spectra and achieve a temperature accuracy of 0.23 °C at a high data acquisition rate of 5 kHz (limited by the spectrometer). This represents a tenfold improvement in accuracy compared to conventional peak-searching and curve-fitting methods, as well as a significant enhancement in measurement speed that enables dynamic sensing. We further assess the robustness of our sensor by attaching one side of the sensor to a vibrator and still observe good performance (0.43 °C) even under strong shaking conditions. The introduced demodulation technology opens up opportunities for the broader use of sapphire FBG sensors in noisy and high-temperature harsh environments.

Defect detection in additively manufactured AlSi10Mg and Ti6Al4V samples using laser ultrasonics and phase shift migration

Laser ultrasonics (LU) is a non-contact and non-destructive method with a high data acquisition rate, making it a promising candidate for in-situ monitoring of defects in different additive manufacturing (AM) processes, including laser powder bed fusion (LPBF) and directed energy deposition, as well as final part inspection. In order to see the effect of various artificial defect types on an LU sub-surface reconstruction, AlSi10Mg samples with side through-holes, as well as Ti6Al4V samples with bottom blind holes and trapped powder were printed using LPBF, and then ultrasound B-scans of the samples were obtained using an LU system. The resulting scan data was processed using a custom frequency domain phase shift migration (PSM) algorithm, to reconstruct the defects and their locations. Novel ways of pre-processing the B-scan, used as an input to PSM, and taking advantage of its frequency representation, are demonstrated. Newton’s method was used to find a stationary phase approximation, used to account in the frequency domain for the fixed offset emitter-receiver arrangement within the PSM calculation. The Newton’s method calculation time was reduced by 33%, by using an approximation of the phase function to find an initial guess. The smallest defects that were detected using this method were in the size range between 200 to 300μm for the bottom hole defects, using an 8 ns laser pulse duration. The effect of the laser on the surface of a part being built, and the challenges and further work needed to integrate LU in a LPBF machine for in-situ inspection are discussed.

Reliability evaluation of the CAEN DT5202 for high-rate data acquisition

Multichannel readout systems play an important role in contemporary physics experiments. Apart from custom-designed highly specialized electronics, several commercial solutions exist on the market. The CAEN DT5202 readout module, comprised of two Citiroc 1A ASICs for a total of 64 channels, was chosen as a typical example. Its performance was studied in specific use cases in a laboratory test environment. The preliminary results of the tests and the evaluation of the hardware module for its applicability in particle detector readout systems are presented. In addition, the control software shipped together with the module has also been studied and its current limitations are discussed.

Rapid generation and number-resolved detection of spinor rubidium Bose-Einstein condensates

High data acquisition rates and low-noise detection of ultracold neutral atoms present important challenges for the state tomography and interferometric application of entangled quantum states in Bose-Einstein condensates. In this article, we present a high-flux source of $^{87}$Rb Bose-Einstein condensates combined with a number-resolving detection. We create Bose-Einstein condensates of $2\times10^5$ atoms with no discernible thermal fraction within $3.3$ s using a hybrid evaporation approach in a magnetic/optical trap. For the high-fidelity tomography of many-body quantum states in the spin degree of freedom [arXiv:2207.01270], it is desirable to select a single mode for a number-resolving detection. We demonstrate the low-noise selection of subsamples of up to $16$ atoms and their subsequent detection with a counting noise below $0.2$ atoms. The presented techniques offer an exciting path towards the creation and analysis of mesoscopic quantum states with unprecedented fidelities, and their exploitation for fundamental and metrological applications.

Toward 4-D Imaging of On-the-Move Object at 2500 Volumetric Frames per Second by Software-Defined Millimeter-Wave MIMO With Compressive Reflector Antenna

Conventional millimeter-wave (mm-wave) security screening systems with synthetic or phased arrays require either mechanical or electronic scans which are slow, thus not capable to image on-the-move objects. This article presents the 4-D imaging of on-the-move objects (1-D velocity and 3-D profile) by leveraging cost-effective compressive reflector antennas (CRAs) and software-defined mm-wave (SDMMW) multiple-in multiple-out (MIMO) arrays. The CRA creates spatial aperture coding to achieve informative measurements and high sensing capacity. The SDMMW MIMO array generates fast space-time-coded frequency-modulated continuous wave (FMCW) for quick data collection and simultaneous MIMO operation. The signal model using the CRAs fed by the SDMMW MIMO arrays in a multistatic configuration is derived, followed by the sensing-matrix-based imaging theory. Then, a proof-of-concept imaging system is designed with a made-in-lab CRA and a modularized 8-by-8 SDMMW array where the fast FMCW modulation achieves a linearized frequency sweep of 5.02 GHz per 50 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${\mu }\text{s}$ </tex-math></inline-formula> , corresponding to a high data acquisition rate of 2500 volumetric frames/s and an unambiguous velocity of ±2.23 m/s. Both simulations and experiments have shown good imaging performance of on-the-move objects, giving great potential for developing future cost-effective high-throughput mm-wave security screening systems.

Assessment of hearing loss risk due to impact noise in industrial environments

Impact noises are often found in industrial environments and they are predominant in mining, construction, factories, workshops, and shipyards. It is well-known that impact noises are more likely to cause noise-induced hearing loss than continuous noise of equal energy. Impulse noises are characterized by their high intensity over a short period of time and many countries have defined impulse noise exposure limits and criteria in occupational settings. They are based on the sound level measurements made using standard sound pressure level meters and dosemeters. However, because of their metrological limitations, it is not appropriate to use these instruments when dealing with such high peak levels and short duration times. Extensive research on hearing damage produced by impulse noise generated by firearms has been presented, mainly on police and military personnel. These studies have led to damage risk criteria contained in various versions of the standard MIL-STD-1474. Although industrial noises can reach similar peak sound pressure levels, not many results have been published on the subject. In this work, several common sources of industrial impact noise were measured in-situ, at the worker locations, using a specialized system equipped with high-dynamic-range microphones and a very high data acquisition rate. The signals were post-processed to obtain the main metrics defined for impulse noise exposure assessment. Then, occupational hearing loss risk was estimated using different criteria. It is shown that many common industrial processes reported a very high risk of impulsive noise to human hearing.

On the measurement of hardness at high strain rates by nanoindentation impact testing

Recent advances in electronics have enabled nanomechanical measurements with very low noise, fast time constants and high data acquisition rates. These capabilities open the door for a wide range of ultra-fast nanomechanical testing. Given the inherent dynamic nature of high-speed testing, a thorough understanding of the testing system's dynamics and electronics is extremely important for accurate measurements. In this work, an analytical framework that includes the mechanical and electronic contributions of the instrument and the material constitutive response is presented to provide guidelines for performing high strain rate measurements of hardness by nanoindentation testing. Simple closed-form solutions that provide insights on the choice of test methodology, test parameters and instrument design are presented along with the strain rate range over which accurate measurements can be performed with commercially available nanoindenters.

Construction of Landscape Ecological Planning Evaluation Model Based on Sensor Network

The application of wireless sensor network (WSN) technology promotes the modernization of forestry. WSN application technology in forest areas is an important research topic for the sustainable development of forestry in China and is also a research hotspot for forestry ecological monitoring at present. The application of wireless sensor networks in forest areas, first of all, solves the problem of limited energy supply and low-latency data transmission in the forest environment. Due to the large area of the forest environment and uneven tree density, dynamic changes in forest height, easy to block the signal, and other characteristics, the forest environment is prone to node energy depletion fast, the network life cycle is short, and data transmission delays large dilemma. Second, the application of wireless sensor networks is usually centered on maximum data acquisition, but the contradiction between high data acquisition rate and limited energy supply is inevitable, so it is necessary to construct a maximum data acquisition rate model with limited energy supply as a constraint to guarantee the optimal acquisition conditions for wireless sensor networks. In this paper, from the application of wireless sensor network technology in forest environment, the research on the application of wireless sensor network in forestry is carried out around the analysis of energy self-collection permanent function of sensor nodes, sensor node transmission routing strategy, data collection, fusion, and fuzzy inference decision-making fire danger warning process, so as to provide a solution to the overall problem of forest fire warning based on rechargeable wireless sensor network. In this paper, we analyze the dynamic replenishment of energy in rechargeable wireless sensor networks and propose an energy-based transmission control protocol that effectively improves data transmission efficiency. In the rechargeable wireless sensor network, the network E2E (end-to-end) average delay time is calculated based on the number of nodes on the data transmission link. The research idea of this paper starts from the application technology of wireless sensor network in the forest environment, and the design of the energy self-collection permanent function of sensor nodes, sensor node transmission routing strategy, data collection, fusion, and fuzzy inference decision fire danger warning process are realized vertically.

Abstract 2322: Multiplatform metabolomics studies of human cancers with NMR and mass spectrometry imaging

Abstract Unfortunately, at present, there is no single technique that possesses all the characteristics needed to be considered an ideal global metabolite profiling tool. Thus, the use of multiple analytical platforms, such as combining the strengths of Mass spectrometry (MS) and nuclear magnetic resonance spectroscopy (NMR), for metabolic profiling can maximize coverage and generate more global metabolomic profiles. In this study, we demonstrate the utilities of the combined NMR and MSI multiplatform in our metabolomics results on human prostate and lung cancers. Statistical data on the natural history of prostate cancer (PCa) show that &amp;gt;70% of patients diagnosed by PSA screening will likely experience indolent disease with little impact on well-being. For about 17% of newly PSA-diagnosed patients, however, aggressive PCa proliferation ensues, truncating life expectancy. At present, no reliable clinical test can differentiate between these two groups. Using HRMAS 1HNMR followed by quantitative histology, we showed statistically significant correlations between concentrations of Spm and the amount of histologically-benign epithelial (Hb Epi) prostatic cells and glands in human cancerous prostates. However, as above discussed that using HRMAS NMR alone we cannot prove that Spm was indeed generated or resided in the Hb Epi cells. Nevertheless, using MALDI MSI, we were able to locate Spm (m/z: 203.223 ± 0.001Da) onto Hb Epi, where spermine on the PCa lesions appeared below detection limits. From these maps, for the first time, we could visualize and confirm the differential localizations of Spm in prostates. This proof of Sym relationship to prostate pathologies and its proposed PCa inhibitory effects may support further studies that are critical in differentiating aggressive from indolent PCa for disease evaluations and patient personalized treatment strategies. To search for such screening metabolomics biomarkers in lung cancer, we used HRMAS NMR to analyze 93 pairs of human LuCa tissue and serum samples, and 29 healthy human sera. A number of potential metabolite candidates capable to differentiate LuCa characteristics were identified, including glutamate, lipids, alanine, glycerylphosphorylcholine, glutamine, phosphorylcholine, etc. This list can be further expanded by analyzing metabolite composition in the serum of cancer patients and control healthy subjects using LC-MS, which offers a dramatic increase in sensitivity compared to HRMAS NMR and, therefore, is better suited for the biomarker discovery. In addition to acquiring high-resolution mass data, the high data acquisition rate allows the fragment ion mass spectra (MS/MS) to be generated for the most abundant ionic species in each chromatographic peak. This feature allows specific classes of tumor-attenuated metabolites to be identified based on the presence of unique structurally diagnostic fragment ions in MS/MS spectra. Citation Format: Leo L. Cheng, Anya B. Zhong, Isabella H. Muti, Stephen J. Eyles, Richard W. Vachet, Sylwia A. Stopka, Kristen N. Sikora, Cedric E. Bobst, Jeffrey N. Agar, Mari A. Mino-Kenudson, Chin-Lee Wu, David C. Christiani, Igor A. Kaltashov, Nathalie Y. Agar. Multiplatform metabolomics studies of human cancers with NMR and mass spectrometry imaging [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2322.

XBeats: A Real-Time Electrocardiogram Monitoring and Analysis System

This work presents XBeats, a novel platform for real-time electrocardiogram monitoring and analysis that uses edge computing and machine learning for early anomaly detection. The platform encompasses a data acquisition ECG patch with 12 leads to collect heart signals, perform on-chip processing, and transmit the data to healthcare providers in real-time for further analysis. The ECG patch provides a dynamically configurable selection of the active ECG leads that could be transmitted to the backend monitoring system. The selection ranges from a single ECG lead to a complete 12-lead ECG testing configuration. XBeats implements a lightweight binary classifier for early anomaly detection to reduce the time to action should abnormal heart conditions occur. This initial detection phase is performed on the edge (i.e., the device paired with the patch) and alerts can be configured to notify designated healthcare providers. Further deep analysis can be performed on the full fidelity 12-lead data sent to the backend. A fully functional prototype of the XBeats has been implemented to demonstrate the feasibly and usability of the proposed system. Performance evaluation shows that XBeats can achieve up to 95.30% detection accuracy for abnormal conditions, while maintaining a high data acquisition rate of up to 441 samples per second. Moreover, the analytical results of the energy consumption profile show that the ECG patch provides up to 37 h of continuous 12-lead ECG streaming.

Dynamic ellipsometry measurement based on a simplified phase-stable dual-comb system.

Spectroscopic ellipsometry is a powerful tool for characterizing thin film, polarization optics, semiconductors, and others. Conventional approaches are subject to restrictions of mechanical instability and measurement speed. The complex locking scheme of previous dual-comb spectroscopic ellipsometry belies its practicability. We present and demonstrate here dynamic spectroscopic ellipsometry based on a simplified phase-stable dual-comb system, which could realize the online dynamic measurement of optical properties of materials. A precision of 1.31 nm and a combined uncertainty of 13.80 nm (k = 2) in the thickness measurement of thin-film samples has been achieved. Moreover, the dynamic performance of the system is investigated under a high data acquisition rate (1 kHz) with a dynamic resolution of ellipsometric parameter better than 0.1 rad.

Statistical Characteristics of the Low‐Latitude E‐Region Irregularities Observed by the HCOPAR in South China

AbstractStatistical characteristics of the E‐region irregularities observed by the HCOPAR in the low‐latitudes of China are presented and analyzed. The data come from the observations between September 2015 and August 2016. Benefit from the high data acquisition rate and the relatively high time and height resolutions, we have found many interesting and unreported details in the statistical characteristics of the E‐region irregularities. The lowest occurrence rate of the E‐region irregularities appears at around sunrise and another low rate appears at around noon. The daytime irregularities are generated in the region where the zonal winds turn around at the E‐region altitudes. There is clear boundary between the irregularities occurring in the morning and afternoon. The nighttime irregularities appear at higher altitudes with steeper background plasma density gradient. The higher tidal amplitude is suggested to increase the irregularity occurrence rate and the greater solar radiation is suggested to decrease it. The steep plasma density gradient in the night may be the main reason for the nighttime irregularities through gradient drift instability. The turning around of the zonal wind field is considered to generate the irregularities in the day through Kelvin‐Helmholtz instability.

A novel approach for microscale dry contact stiction and friction assessment: Experimentation and analysis

Accurate and quantitative evaluation of friction is of fundamental interest for materials science and manufacturing. Driven by the trend towards miniaturization, micro metal forming techniques with characteristic forming dimensions approaching a few microns have developed rapidly over the past two decades. In contrast, the assessment of microscale friction is lagging. Here, we present a novel test, compression molding and demolding test (CMDT), to assess stiction and friction at the microscale. CMDT was conducted via in-situ instrumented molding and demolding of an Al specimen with cylindrical tool steel and Ti alloy punches. High-rate data acquisition enabled direct measurements, for the first time, of microscale stiction and friction forces during disengagement between the punches and the molded Al under dry contact conditions. Stiction and friction stresses were then deduced and analyzed. The average friction coefficient was estimated by combining the cavity expansion model and finite element method analysis. Examinations suggest that punch geometry and surface finish, together with the accuracy of estimating the sidewall contact pressure, influence the obtained friction coefficient values. CMDT exhibits merits such as high operation simplicity and measurement accuracy and offers an alternative approach to providing new experimental evidence for a range of microscale friction problems.

Upgrade of a Highly Sensitive Monitor for Atmospheric Radon Measurement

Atmospheric radon is an ideal tracer that is widely used in atmospheric science. To meet the need fora continuous online measurement of atmospheric radon concentration, an upgraded radon monitor based on an electrostatic collection method was developed following Iida’s measurement system. Two major improvements have been realized. First, an 18 mm × 18 mm Si-PIN detector and a multi-channel analysis system were used to distinguish different alpha particles. Second, the P2O5 desiccant was replaced by a new membrane drying system, and the influence of humidity was corrected by a humidity correction coefficient. Calibration and comparison experiments were carried out in detail, and a one-year continuous measurement was also performed. Results showed that the measurement sensitivity was evaluated to be 24.3 cph/(Bq·m−3), and the lower level detection limit was 0.2 Bq·m−3 for a 1-h cycle at the absolute humidity of 0.34 g·m−3. The annual average radon concentration of Beijing was 11.1 ± 4.0 Bq·m−3, which changed from 2.8 Bq·m−3 to 30.3 Bq·m−3 between 15 October 2018 and 1 October 2019. The upgraded monitor’s high data acquisition rate and good performance indicate that it is suitable for long-term observation on atmospheric radon.

Simple approach for extending the ambiguity-free range of dual-comb ranging.

Dual-comb (DC) ranging is an established method for high-precision and high-accuracy distance measurements. It is, however, restricted by an inherent length ambiguity and the requirement for complex control loops for comb stabilization. Here, we present a simple approach for expanding the ambiguity-free measurement length of DC ranging by exploiting the intrinsic intensity modulation of a single-cavity dual-color DC for simultaneous time-of-flight and DC distance measurements. This measurement approach enables the measurement of distances up to several hundred kilometers with the precision and accuracy of a DC interferometric setup while providing a high data acquisition rate (≈2kHz) and requiring only the repetition rate of one of the combs to be stabilized.

Linear array focused-laser differential interferometry for single-shot multi-point flow disturbance measurements.

In this Letter, a modification of the well-known focused-laser differential interferometer (FLDI) is demonstrated, with the primary focus being increasing the number of probed locations efficiently. To generate multiple beams in the FLDI system, a diffractive optical element is used. This approach is significantly more cost-effective and easier to implement than the current approach of generating multiple FLDI beam pairs using a series of Wollaston prisms. The measurements shown here utilize a 1D linear array of points, and the ability to generate a 2D array is demonstrated using two linear diffractive optical elements in tandem. Therefore, this technique, referred to as linear array FLDI (LA-FLDI), is able to provide measurements of fluid disturbances at multiple discrete locations while allowing for high data acquisition rates (>1MHz). This technique provides a much simpler approach to multipoint FLDI measurements and can increase the throughput of FLDI measurements in impulse aerospace testing facilities.

Imaging Resolution Analysis of Single-Frequency and Single-Sensor Programmable Microwave Imager

Over the past years, the single-frequency and single-sensor microwave imager using programmable metasurface, called programmable microwave imager for short, has attracted researchers' attention because of its unique advantages over conventional imaging schemes in the lower hardware cost, the higher data-acquisition rate, and the property of non-frequency dispersion. In this communication, we focus on the resolution performance of such imaging scheme, where we specifically demonstrate for the first time that the 3-D resolution can be achieved using the programmable microwave imager and a 3-D image reconstruction has been simulated successfully. We provide insights into the 3-D imaging resolution of programmable imager from two perspectives, i.e., the Ewald sphere and the point spread function (PSF). The influences on the 3-D imaging resolution of some important factors are theoretically and numerically investigated, including the distance between the object and the metasurface, the metasurface's size, and its coding style.

Influence of acquisition rate on performance of fast comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry for coconut fiber bio-oil characterization

Comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC × GC/TOFMS) is used to characterize complex bio-oil samples because of the high peak capacity associated with the high acquisition rate and mass spectra deconvolution capability of TOFMS. A recent application of fast GC × GC for this type of analysis improved sample throughput while achieving the same peak capacity without the use of cryogenic liquids. This work evaluates the effect of the TOFMS data acquisition rate on the quality of the analytical information obtained by GC × GC/TOFMS. In the analysis of coconut fiber bio-oil under fast GC × GC/TOFMS conditions, use of high data acquisition rates (200–300 Hz) increases the number of identifiable peaks by more than 50% compared with that achieved at the conventional rate of 100 Hz. The acquisition rate can affect the peak capacity by a factor of 3 or more. This is the first study to demonstrate the importance of optimizing the data acquisition rate, a parameter that has previously been neglected in the literature, in GC × GC/TOFMS development.

The CLAS12 Spectrometer at Jefferson Laboratory

The CEBAF Large Acceptance Spectrometer for operation at 12 GeV beam energy (CLAS12) in Hall B at Jefferson Laboratory is used to study electro-induced nuclear and hadronic reactions. This spectrometer provides efficient detection of charged and neutral particles over a large fraction of the full solid angle. CLAS12 has been part of the energy-doubling project of Jefferson Lab’s Continuous Electron Beam Accelerator Facility, funded by the United States Department of Energy. An international collaboration of 48 institutions contributed to the design and construction of detector hardware, developed the software packages for the simulation of complex event patterns, and commissioned the detector systems. CLAS12 is based on a dual-magnet system with a superconducting torus magnet that provides a largely azimuthal field distribution that covers the forward polar angle range up to 35∘, and a solenoid magnet and detector covering the polar angles from 35° to 125° with full azimuthal coverage. Trajectory reconstruction in the forward direction using drift chambers and in the central direction using a vertex tracker results in momentum resolutions of <1% and <3%, respectively. Cherenkov counters, time-of-flight scintillators, and electromagnetic calorimeters provide good particle identification. Fast triggering and high data-acquisition rates allow operation at a luminosity of 1035 cm−2s−1. These capabilities are being used in a broad program to study the structure and interactions of nucleons, nuclei, and mesons, using polarized and unpolarized electron beams and targets for beam energies up to 11 GeV. This paper gives a general description of the design, construction, and performance of CLAS12.

Online energy reconstruction for calorimeters under high pile-up conditions using deconvolutional techniques

High-energy calorimeters operating at high data acquisition rate may suffer from signal superposition (pile-up) in their electronic readout. This problem occurs whenever the time interval among two subsequent incoming physics signatures is shorter than the front-end electronics time latency. Signal pile-up may cause severe problems on the online energy estimation and some palliative solutions, treating the pile-up signals as an additional noise source, have been proposed in order to preserve the well established Optimal Filter theory as the signal estimation baseline design. In order to produce actual online compensation for pile-up effect, the method proposed in this paper approximates the front-end electronics as a linear transmission channel whose transfer function can be linearly equalized (unconvolved). For experiments where the acquisition rate is synchronized with the collision clock, the equalizer output provides a straightforward energy estimation per bunch-crossing (BC). Optimal approximations for the equalizer design are proposed using both FIR (Finite Impulse Response) filters and an iterative method. The latter offers better reconstruction performance (smaller errors), but has higher computational cost and requires extra data-flow circuitry when online implementation is envisaged. Toy simulation data that consider typical calorimeter front-end responses are used to evaluate the performance of the proposed methods.