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- 实验方案
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Impact of Transportation on Indian Roads, on PV Modules
摘要： This paper addresses the application of rotor speed signal for the detection and diagnosis of ball bearing faults in rotating electrical machines. Many existing techniques for bearing fault diagnosis (BFD) rely on vibration signals or current signals. However, vibration- or current-based BFD techniques suffer from various challenges that must be addressed. As an alternative, this paper takes the initial step of investigating the efficiency of rotor speed monitoring for BFD. The bearing failure modes are reviewed and their effects on the rotor speed signal are described. Based on this analysis, a novel BFD technique, the rotor speed-based BFD (RSB-BFD) method under variable speed and constant load conditions, is proposed to provide a benefit in terms of cost and simplicity. The proposed RSB-BFD method exploits the absolute value-based principal component analysis (PCA), which improves the performance of classical PCA by using the absolute value of weights and the sum square error. The performance and effectiveness of the RSB-BFD method is demonstrated using an experimental setup with a set of realistic bearing faults in the outer race, inner race, and balls.
关键词： principal component analysis (PCA),rotor speed,sum square error,Bearing fault diagnosis (BFD),variable speed
更新于2025-09-19 17:13:59
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Improved electro-optic chaotic system with nonlinear electrical coupling
摘要： Design disjunction is developed to offer a broad coverage, high resolution, and low overhead approach to online diagnosis and recovery of recon?gurable fabrics. Design disjunction leverages the condensed diagnosability of T logic resources to achieve self-recovery using partial recon?guration in O(log T ) steps. Recon?guration is guided by the constructive property of f-disjunctness which forms O(log T ) resource groups at design-time. Resolution of f simultaneous resource faults is shown to be guaranteed when the resource groups are mutually f-disjunct. This extends run-time fault resilience to a large resource space with certainty for up to f faults using a decision-free resolution process that also provides a high likelihood of identifying the fault’s location to a ?ne granularity. Finally, design disjunction is parameterized to accommodate the low coverage issue of functional testing for which inarticulate tests can otherwise impair fault isolation. Experimental results for MCNC and ISCAS benchmarks on a Xilinx 7-series ?eld programmable gate array (FPGA) demonstrate f-diagnosability at the individual slice level with a minimum average isolation accuracy of 96:4 percent (94:4 percent) for f ? 1 (f ? 2). Results have also demonstrated millisecond order recovery with a minimum increase of 83:6 percent in fault coverage compared to N-modular redundancy (NMR) schemes. Recovery is achieved while incurring an average critical path delay impact of only 1:49 percent and energy cost roughly comparable to conventional two-MR approaches.
关键词： online test,run-time fault diagnosis and recovery,design space exploration,Recon?gurable logic devices,autonomous fault handling,fault-tolerant systems,?eld programmable gate arrays
更新于2025-09-19 17:13:59
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[IEEE 2019 Photonics North (PN) - Quebec City, QC, Canada (2019.5.21-2019.5.23)] 2019 Photonics North (PN) - Continuous-wave Nd:YVO <sub/>4</sub> laser with conical refraction output
摘要： A particle ?lter (PF)-based robust navigation with fault diagnosis (FD) is designed for an underwater robot, where 10 failure modes of sensors and thrusters are considered. The nominal underwater robot and its anomaly are described by a switching-mode hidden Markov model. By extensively running a PF on the model, the FD and robust navigation are achieved. Closed-loop full-scale experimental results show that the proposed method is robust, can diagnose faults effectively, and can provide good state estimation even in cases where multiple faults occur. Comparing with other methods, the proposed method can diagnose all faults within a single structure, diagnose simultaneous faults, and it is easily implemented.
关键词： fault tolerance,Fault diagnosis (FD),remotely operated underwater vehicle (ROV),switch-mode hidden Markov model (HMM),particle ?lter (PF),underwater navigation
更新于2025-09-19 17:13:59
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An Ultra-Wideband Power Combining in Ridge Waveguide for Millimeter Wave
摘要： Valid characterization of carotid atherosclerosis (CA) is a crucial public health issue, which would limit the major risks held by CA for both patient safety and state economies. This paper investigated the unexplored potential of kinematic features in assisting the diagnostic decision for CA in the framework of a computer-aided diagnosis (CAD) tool. To this end, 15 CAD schemes were designed and were fed with a wide variety of kinematic features of the atherosclerotic plaque and the arterial wall adjacent to the plaque for 56 patients from two different hospitals. The CAD schemes were benchmarked in terms of their ability to discriminate between symptomatic and asymptomatic patients and the combination of the Fisher discriminant ratio, as a feature-selection strategy, and support vector machines, in the classification module, was revealed as the optimal motion-based CAD tool. The particular CAD tool was evaluated with several cross-validation strategies and yielded higher than 88% classification accuracy; the texture-based CAD performance in the same dataset was 80%. The incorporation of kinematic features of the arterial wall in CAD seems to have a particularly favorable impact on the performance of image-data-driven diagnosis for CA, which remains to be further elucidated in future prospective studies on large datasets.
关键词： motion analysis,Carotid atherosclerosis (CA),kinematic features,ultrasound (US),computer-aided diagnosis (CAD)
更新于2025-09-19 17:13:59
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Infrared spectroscopy coupled to cloud-based data management as a tool to diagnose malaria: a pilot study in a malaria-endemic country
摘要： Background: Widespread elimination of malaria requires an ultra?sensitive detection method that can detect low parasitaemia levels seen in asymptomatic carriers who act as reservoirs for further transmission of the disease, but is inexpensive and easy to deploy in the field in low income settings. It was hypothesized that a new method of malaria detection based on infrared spectroscopy, shown in the laboratory to have similar sensitivity to PCR based detection, could prove effective in detecting malaria in a field setting using cheap portable units with data management systems allowing them to be used by users inexpert in spectroscopy. This study was designed to determine whether the methodology developed in the laboratory could be translated to the field to diagnose the presence of Plasmodium in the blood of patients presenting at hospital with symptoms of malaria, as a precursor to trials testing the sensitivity of to detect asymptomatic carriers. Methods: The field study tested 318 patients presenting with suspected malaria at four regional clinics in Thailand. Two portable infrared spectrometers were employed, operated from a laptop computer or a mobile telephone with in?built software that guided the user through the simple measurement steps. Diagnostic modelling and validation testing using linear and machine learning approaches was performed against the gold standard qPCR. Sample spectra from 318 patients were used for building calibration models (112 positive and 110 negative samples according to PCR testing) and independent validation testing (39 positive and 57 negatives samples by PCR). Results: The machine learning classification (support vector machines; SVM) performed with 92% sensitivity (3 false negatives) and 97% specificity (2 false positives). The Area Under the Receiver Operation Curve (AUROC) for the SVM classification was 0.98. These results may be better than as stated as one of the spectroscopy false positives was infected by a Plasmodium species other than Plasmodium falciparum or Plasmodium vivax, not detected by the PCR primers employed. Conclusions: In conclusion, it was demonstrated that ATR?FTIR spectroscopy could be used as an efficient and reliable malaria diagnostic tool and has the potential to be developed for use at point of care under tropical field conditions with spectra able to be analysed via a Cloud?based system, and the diagnostic results returned to the user’s mobile telephone or computer. The combination of accessibility to mass screening, high sensitivity and selectivity, low logistics requirements and portability, makes this new approach a potentially outstanding tool in the context of malaria elimination programmes. The next step in the experimental programme now underway is to reduce the sample requirements to fingerprick volumes.
关键词： Plasmodium,Cloud based diagnostics,Infrared spectroscopy,Malaria diagnosis
更新于2025-09-19 17:13:59
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Detection and Quantification of HspX Antigen in Sputum Samples Using Plasmonic Biosensing: Toward a Real Point-of-Care (POC) for Tuberculosis Diagnosis
摘要： Advances occurred during the last years in the diagnosis of Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis infection, have prompted increased survival rates of patients. However, limitations related to the inefficiency of an early detection still remain: some techniques and laboratory methods do not have enough specificity, most instruments are expensive, and require handling by trained staff. In order to contribute to a prompt and effective diagnosis of tuberculosis, we report the development of a portable, user-friendly and low-cost biosensor device for its early detection. By using a label-free Surface Plasmon Resonance (SPR) biosensor, we have established a direct immunoassay for the direct detection and quantification of the Heat shock protein X (HspX) of Mtb, a well-established biomarker of this pathogen, directly in pre-treated sputum samples. The method relies on highly specific monoclonal antibodies which are previously immobilized on the plasmonic sensor surface. This technology allows the direct detection of the biomarker without amplification steps, showing a Limit of Detection (LOD) of 0.63 ng mL-1 and a Limit of Quantification (LOQ) of 2.12 ng mL-1. The direct analysis in pre-treated sputum shows significant differences in the HspX concentration in patients with tuberculosis (with concentration levels in the order of 116-175 ng mL-1) compared with non-tuberculosis infected patients (values below the LOQ of the assay).
关键词： SPR Immunosensor,Tuberculosis diagnosis,HspX recombinant protein,human sputum samples,Point-of-Care device
更新于2025-09-19 17:13:59
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<p>Preparation and SPECT/CT Imaging of <sup>177</sup>Lu-Labeled Peptide Nucleic Acid (PNA) Targeting CITED1: Therapeutic Evaluation in Tumor-Bearing Nude Mice</p>
摘要： The expression of Cbp/p300-interacting transactivator with Glu/Asp-rich carboxy-terminal domain 1 (CITED1) is upregulated in papillary thyroid carcinoma (PTC) and mediates cell proliferation and migration. To facilitate early diagnosis and monitoring of recurrent or metastatic PTC, we designed 177Lu-labeled antisense peptide nucleic acid (PNA) targeting CITED1 mRNA to evaluate the therapeutic potential, while analyzing its distribution in nude mice and the characteristics with single-photon emission-computed tomography/computed tomography (SPECT/CT) imaging.
关键词： SPECT/CT imaging,antisense therapy,diagnosis and treatment integration,papillary thyroid carcinoma
更新于2025-09-19 17:13:59
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Laser-induced fluorescence spectroscopy for early disease detection in grapefruit plants
摘要： Both biotic and abiotic stress causes considerable decrease in chlorophyll content in plant leaves which provide the means of early disease diagnosis. The emergence of disease affects the fluorescence of phenolic compounds and chlorophyll which have been appeared at 530, 686 and 735 nm. It has been found that the intensity of emission band of phenolic compounds at 530 nm increases and that of chlorophyll at 735 nm decreases with the onset of disease. Statistical analysis through principal component analysis (PCA) and partial least square regression (PLSR) has been performed which demonstrated the classification of apparently healthy leaf sites with diseased ones which provide the basis for the detection of disease at early stages. PLSR model was validated through the coefficient of determination (R2), standard error of prediction (SEP) and standard error of calibration (SEC) with the values 0.99, 0.394 and 0.401 which authenticated the model. The prediction accuracy of the model was evaluated through root mean square error in prediction (RMSEP) of 0.14 by predicting 22 unknown emission spectra of different leaf sites. Both PCA and PLSR models produced similar results and proved fluorescence spectroscopy as an excellent tool for early disease detection in plants.
关键词： Early disease diagnosis,Principal component analysis (PCA),Chlorophyll fluorescence,Partial least square regression (PLSR),Phenolic compounds
更新于2025-09-19 17:13:59
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Optical nanogap antennas as plasmonic biosensors for the detection of miRNA biomarkers
摘要： Nanoplasmonic biosensors based on nanogap antennas structures usually demand complex and expensive fabrication processes in order to achieve a good performance and sensitive detection. We here report the fabrication of large-area nanoplasmonic sensor chips based on nanogap antennas by employing a customized, simple and low-cost colloidal lithography process. By precisely controlling the angle for tilted e-beam metal evaporation, an elliptical mask is produced, which defines the total length of the dipole antenna nanostructures while assuring that the plasmonic response is oriented in the same direction along the sensor chip. Large-area sensor chips of nanogap antennas formed by pairs of gold nanodisks separated by gaps with an average size of 11.6 ± 4.7 nm are obtained. The optical characterization of the nanogap antenna structures in an attenuated total reflection (ATR) configuration shows a bulk refractive index sensitivity of 422 nm/RIU, which is in agreement with FDTD numerical simulations. The biosensing potential of the cm2-sized nanostructured plasmonic sensor chips has been evaluated for the detection of miRNA-210, a relevant biomarker for lung cancer diagnosis, through a DNA/miRNA hybridization assay. A limit of detection (LOD) of 0.78?nM (5.1 ng mL-1) was achieved with no need of further amplification steps, demonstrating the high sensitivity of these plasmonic nanogap antennas for the direct and label-free detection of low molecular weight biomolecules as miRNAs.
关键词： nanoplasmonic biosensors,miRNA biomarkers,colloidal lithography,nanogap antennas,lung cancer diagnosis
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 8th International Conference on Advanced Optoelectronics and Lasers (CAOL) - Sozopol, Bulgaria (2019.9.6-2019.9.8)] 2019 IEEE 8th International Conference on Advanced Optoelectronics and Lasers (CAOL) - Nonlinear Wave Dynamics of Unstable Atherosclerotic Plaque
摘要： Fault diagnosis of inductions motors has received much attention recently. Most of the works use data obtained either from the time domain or by applying advanced techniques in the frequency domain. Some researchers have employed a considerable effort in designing sophisticated algorithms to achieve the best performance of the diagnosis system. However, some contributions in the field have not taken advantage of the benefits that a good evaluation stage can bring to the developing of classifiers for fault diagnosis. In this paper, novel insights for the classifier evaluation are presented to promote better assessment practices in the field of electric machine diagnosis based on supervised classification. A case of study consisting of a motor with a broken rotor bar is described to analyze the performance of two classifiers by using scores focused on the fault detection. Also, different error estimation methods are considered to obtain unbiased predictive performances. Two statistical tests are also discussed to confirm the significance of the results under a single data set.
关键词： fault diagnosis,Broken rotor bar,electric machines,classification algorithm,condition monitoring,performance evaluation
更新于2025-09-19 17:13:59