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Sensors (Basel, Switzerland) Apr 2023This paper addresses the current challenges in cybersecurity of smart metering infrastructure, specifically in relation to the Czech Decree 359/2020 and the DLMS...
This paper addresses the current challenges in cybersecurity of smart metering infrastructure, specifically in relation to the Czech Decree 359/2020 and the DLMS security suite (device language message specification). The authors present a novel testing methodology for verifying cybersecurity requirements, motivated by the need to comply with European directives and legal requirements of the Czech authority. The methodology encompasses testing cybersecurity parameters of smart meters and related infrastructure, as well as evaluating wireless communication technologies in the context of cybersecurity requirements. The article contributes by summarizing the cybersecurity requirements, creating a testing methodology, and evaluating a real smart meter, using the proposed approach. The authors conclude by presenting a methodology that can be replicated and tools that can be used to test smart meters and the related infrastructure. This paper aims to propose a more effective solution and takes a significant step towards improving the cybersecurity of smart metering technologies.
PubMed: 37112383
DOI: 10.3390/s23084043 -
Nature Communications Feb 2023Electron beam quality is paramount for X-ray pulse production in free-electron-lasers (FELs). State-of-the-art linear accelerators (linacs) can deliver multi-GeV...
Electron beam quality is paramount for X-ray pulse production in free-electron-lasers (FELs). State-of-the-art linear accelerators (linacs) can deliver multi-GeV electron beams with sufficient quality for hard X-ray-FELs, albeit requiring km-scale setups, whereas plasma-based accelerators can produce multi-GeV electron beams on metre-scale distances, and begin to reach beam qualities sufficient for EUV FELs. Here we show, that electron beams from plasma photocathodes many orders of magnitude brighter than state-of-the-art can be generated in plasma wakefield accelerators (PWFAs), and then extracted, captured, transported and injected into undulators without significant quality loss. These ultrabright, sub-femtosecond electron beams can drive hard X-FELs near the cold beam limit to generate coherent X-ray pulses of attosecond-Angstrom class, reaching saturation after only 10 metres of undulator. This plasma-X-FEL opens pathways for advanced photon science capabilities, such as unperturbed observation of electronic motion inside atoms at their natural time and length scale, and towards higher photon energies.
Topics: Electrons; Particle Accelerators; X-Rays; Lasers; Photons
PubMed: 36828817
DOI: 10.1038/s41467-023-36592-z -
Sensors (Basel, Switzerland) Jul 2023Meter reading is an important part of intelligent inspection, and the current meter reading method based on target detection has problems of low accuracy and large...
Meter reading is an important part of intelligent inspection, and the current meter reading method based on target detection has problems of low accuracy and large error. In order to improve the accuracy of automatic meter reading, this paper proposes an automatic reading method for pointer-type meters based on the YOLOv5-Meter Reading (YOLOv5-MR) model. Firstly, in order to improve the detection performance of small targets in YOLOv5 framework, a multi-scale target detection layer is added to the YOLOv5 framework, and a set of Anchors is designed based on the lightning rod dial data set; secondly, the loss function and up-sampling method are improved to enhance the model training convergence speed and obtain the optimal up-sampling parameters; Finally, a new external circle fitting method of the dial is proposed, and the dial reading is calculated by the center angle algorithm. The experimental results on the self-built dataset show that the Mean Average Precision (mAP) of the YOLOv5-MR target detection model reaches 79%, which is 3% better than the YOLOv5 model, and outperforms other advanced pointer-type meter reading models.
PubMed: 37514937
DOI: 10.3390/s23146644 -
Scientific Reports May 2022Physical unclonable functions (PUF) are cryptographic primitives employed to generate true and intrinsic randomness which is critical for cryptographic and secure...
Physical unclonable functions (PUF) are cryptographic primitives employed to generate true and intrinsic randomness which is critical for cryptographic and secure applications. Thus, the PUF output (response) has properties that can be utilized in building a true random number generator (TRNG) for security applications. The most popular PUF architectures are transistor-based and they focus on exploiting the uncontrollable process variations in conventional CMOS fabrication technology. Recent development in emerging technology such as memristor-based models provides an opportunity to achieve a robust and lightweight PUF architecture. Memristor-based PUF has proven to be more resilient to attacks such as hardware reverse engineering attacks. In this paper, we design a lightweight and low-cost memristor PUF and verify it against cryptographic randomness tests achieving a unique, reliable, irreversible random sequence output. The current research demonstrates the architecture of a low-cost, high endurance Cu/HfO[Formula: see text]Si memristor-based PUF (MR-PUF) which is compatible with advanced CMOS technologies. This paper explores the 15 NIST cryptographic randomness tests that have been applied to our Cu/HfO[Formula: see text]Si MR-PUF. Moreover, security properties such as uniformity, uniqueness, and repeatability of our MR-PUF have been tested in this paper and validated. Additionally, this paper explores the applicability of our MR-PUF on block ciphers to improve the randomness achieved within the encryption process. Our MR-PUF has been used on block ciphers to construct a TRNG cipher block that successfully passed the NIST tests. Additionally, this paper investigated MR-PUF within a new authenticated key exchange and mutual authentication protocol between the head-end system (HES) and smart meters (SM)s in an advanced metering infrastructure (AMI) for smartgrids. The authenticated key exchange protocol utilized within the AMI was verified in this paper to meet the essential security when it comes to randomness by successfully passing the NIST tests without a post-processing algorithm.
PubMed: 35606367
DOI: 10.1038/s41598-022-11240-6 -
Terapevticheskii Arkhiv Dec 2023A point-of-care glucose testing (POCT) is an essential component of care in patients with hyperglycemia and hypoglycemia in inpatient and outpatient settings. In Russian...
BACKGROUND
A point-of-care glucose testing (POCT) is an essential component of care in patients with hyperglycemia and hypoglycemia in inpatient and outpatient settings. In Russian medical facilities (MFs), conventional glucose meters designed for self-monitoring by patients with diabetes are commonly used for POCT. These home-use meters have two serious disadvantages: the first is large measurement bias and the second - they can't be integrated into laboratory information systems, so measurement data have to be recorded into patient charts manually. Both factors may lead to medical errors. It is reasonable to use in the MFs specialized POCT glucose meters, as they are superior to conventional ones in accuracy and may be easily connected to laboratory information systems. With this in mind, physicians at the Russian Children's Clinical Hospital decided to substitute conventional meters with the Accu-Chek Inform II POCT meter, however, after preliminary performance assessment of the model.
AIM
To test the Accu-Chek Inform II performance characteristics: accuracy, linearity, repeatability, and mean absolute relative difference (MARD).
MATERIALS AND METHODS
Performance of the Accu-Chek Inform II was tested by comparing the results of parallel C measurements with the meter and reference laboratory analyzer in capillary blood samples. Overall, 99 parallel C measurements were made in 45 samples. Accuracy was evaluated according to the ISO 15197-2013 and POCT12-A3 criteria.
RESULTS
The Accu-Chek Inform II meter met the requirements of ISO 15197-2013 and POCT12-A3 and demonstrated high linearity (correlation coefficient, =1,0), good repeatability (mean coefficient of variation, CV=1,38%) and acceptable MARD (4,9%).
CONCLUSION
The Accu-Chek Inform II POCT glucose meter may be efficiently and safely used in inpatient and outpatient MFs and particularly in pediatric clinics.
Topics: Humans; Blood Glucose; Blood Glucose Self-Monitoring; Russia; Point-of-Care Systems; Point-of-Care Testing; Reproducibility of Results; Diabetes Mellitus
PubMed: 38785055
DOI: 10.26442/00403660.2023.12.202522 -
Physiotherapy Theory and Practice Dec 2023Backward walking (BW) is an important gait adaptation and BW speed may be an important indicator of walking function and fall risk. However, the measurement...
INTRODUCTION
Backward walking (BW) is an important gait adaptation and BW speed may be an important indicator of walking function and fall risk. However, the measurement characteristics of a standardized assessment of BW post-stroke have not been fully established.
OBJECTIVES
To determine intra- and interrater reliability, concurrent validity and minimal detectable change (MDC) scores for the 3-Meter Backward Walk Test (3MBWT) post-stroke.
METHODS
Thirty-four individuals with subacute and 29 individuals with chronic stroke participated. Two trials of comfortable BW was measured over a total distance of 5-meters, while speed was calculated during the middle 3-meters of the walking distance. Intra and interrater reliability were determined by comparing the two trials from one rater and simultaneous assessment of two raters, respectively. Two additional trials were performed and BW speed was calculated using 3MBWT and an instrumented walkway to determine concurrent validity. Intraclass correlation coefficients (ICC) estimated reliability and validity. The MDC was calculated from the standard error of measurement.
RESULTS
Excellent ICC values were obtained for the 3MBWT in the subacute (interrater: ICC = 0.99; intrarater: ICC = 0.96; validity: ICC = 0.96) and chronic (interrater: ICC = 0.99; intrarater: ICC = 0.94; validity: ICC = 0.97) groups. The MDC was 0.07 m/s (subacute) and 0.11 m/s (chronic).
CONCLUSIONS
Establishment of the 3MBWT as a reliable and valid measure in assessing BW speed is an important addition to the assessment toolbox for rehabilitation post-stroke.
Topics: Humans; Walk Test; Reproducibility of Results; Stroke; Gait; Walking; Stroke Rehabilitation
PubMed: 35658807
DOI: 10.1080/09593985.2022.2085638 -
Scientific Reports May 2024This study addresses the drawbacks of traditional methods used in meter coefficient analysis, which are low accuracy and long processing time. A new method based on...
This study addresses the drawbacks of traditional methods used in meter coefficient analysis, which are low accuracy and long processing time. A new method based on non-parametric analysis using the Back Propagation (BP) neural network is proposed to overcome these limitations. The study explores the classification and pattern recognition capabilities of the BP neural network by analyzing its non-parametric model and optimization methods. For model construction, the study uses the United Kingdom Domestic Appliance-Level Electricity dataset's meter readings and related data for training and testing the proposed model. The non-parametric analysis model is used for data pre-processing, feature extraction, and normalization to obtain the training and testing datasets. Experimental tests compare the proposed non-parametric analysis model based on the BP neural network with the traditional Least Squares Method (LSM). The results demonstrate that the proposed model significantly improves the accuracy indicators such as mean absolute error (MAE) and mean relative error (MRE) when compared with the LSM method. The proposed model achieves an MAE of 0.025 and an MRE of 1.32% in the testing dataset, while the LSM method has an MAE of 0.043 and an MRE of 2.56% in the same dataset. Therefore, the proposed non-parametric analysis model based on the BP neural network can achieve higher accuracy in meter coefficient analysis when compared with the traditional LSM method. This study provides a novel non-parametric analysis method with practical reference value for the electricity industry in energy metering and load forecasting.
PubMed: 38769323
DOI: 10.1038/s41598-024-61702-2 -
Journal of Pediatric Gastroenterology... Jun 2021The aim of the study was to determine the extent of agreement between pH paper and handheld pH meter with a laboratory pH meter for gastric pH measurement in children... (Observational Study)
Observational Study
OBJECTIVES
The aim of the study was to determine the extent of agreement between pH paper and handheld pH meter with a laboratory pH meter for gastric pH measurement in children with neurologic impairments and gastrostomy tubes who have gastroesophageal reflux disease (GERD).
METHODS
In this prospective observational study, gastric contents were aspirated from gastric or nasogastric tubes and the pH measured using 3 techniques: pH paper, handheld pH meter, and laboratory pH meter (the gold standard). Agreement between techniques was assessed with intraclass correlation coefficient (ICC), Bland-Altman analysis, and kappa statistic.
RESULTS
Among 43 patients contributing 67 gastric samples, the ICC was 0.75 (95% confidence interval [CI]: 0.69-0.97) between the handheld and laboratory meters, 0.69 (95% CI: 0.63--0.94) between the pH paper and laboratory meter and 0.69 (95% CI: 0.63-0.94) between the handheld meter and paper. The Bland-Altman analysis between the handheld and lab meters showed a mean difference of -0.03 pH units (limits of agreement: -0.52 to 0.47 pH units) and 0.17 pH units (limits of agreement: -0.99 to 1.33 pH units) between the paper and lab meter. The kappa coefficients for a pH ≥4 were 1.0 (95% CI: 1.0--1.0) between the handheld and lab meters and 0.9 (95% CI: 0.77--1.0) between the paper and lab meter.
CONCLUSIONS
The findings suggest that both point-of-care tests, the pH meter and pH paper, correlate well with the gold standard for testing pH with a laboratory pH meter, indicating usefulness in point-of-care testing for monitoring gastric pH in tube-fed children with neurologic impairments and GERD.
Topics: Child; Enteral Nutrition; Humans; Hydrogen-Ion Concentration; Intubation, Gastrointestinal; Point-of-Care Testing; Stomach
PubMed: 33605659
DOI: 10.1097/MPG.0000000000003087 -
Sensors (Basel, Switzerland) Nov 2020Mechanical power may act as a key indicator for physiological and mechanical changes during running. In this scoping review, we examine the current evidences about the... (Review)
Review
Mechanical power may act as a key indicator for physiological and mechanical changes during running. In this scoping review, we examine the current evidences about the use of power output (PW) during endurance running and the different commercially available wearable sensors to assess PW. The Boolean phrases endurance OR submaximal NOT sprint AND running OR runner AND power OR power meter, were searched in PubMed, MEDLINE, and SCOPUS. Nineteen studies were finally selected for analysis. The current evidence about critical power and both power-time and power-duration relationships in running allow to provide coaches and practitioners a new promising setting for PW quantification with the use of wearable sensors. Some studies have assessed the validity and reliability of different available wearables for both kinematics parameters and PW when running but running power meters need further research before a definitive conclusion regarding its validity and reliability.
Topics: Biomechanical Phenomena; Humans; Physical Endurance; Reproducibility of Results; Running
PubMed: 33202809
DOI: 10.3390/s20226482 -
Sensors (Basel, Switzerland) Jan 2022A large number of power meters have become commercially available during the last decades to provide power output (PO) measurement. Some of these power meters were... (Review)
Review
A large number of power meters have become commercially available during the last decades to provide power output (PO) measurement. Some of these power meters were evaluated for validity in the literature. This study aimed to perform a review of the available literature on the validity of cycling power meters. PubMed, SPORTDiscus, and Google Scholar have been explored with PRISMA methodology. A total of 74 studies have been extracted for the reviewing process. Validity is a general quality of the measurement determined by the assessment of different metrological properties: Accuracy, sensitivity, repeatability, reproducibility, and robustness. Accuracy was most often studied from the metrological property (74 studies). Reproducibility was the second most studied (40 studies) property. Finally, repeatability, sensitivity, and robustness were considerably less studied with only 7, 5, and 5 studies, respectively. The SRM power meter is the most used as a gold standard in the studies. Moreover, the number of participants was very different among them, from 0 (when using a calibration rig) to 56 participants. The PO tested was up to 1700 W, whereas the pedalling cadence ranged between 40 and 180 rpm, including submaximal and maximal exercises. Other exercise conditions were tested, such as torque, position, temperature, and vibrations. This review provides some caveats and recommendations when testing the validity of a cycling power meter, including all of the metrological properties (accuracy, sensitivity, repeatability, reproducibility, and robustness) and some exercise conditions (PO range, sprint, pedalling cadence, torque, position, participant, temperature, vibration, and field test).
Topics: Bicycling; Exercise; Exercise Test; Humans; Reproducibility of Results; Torque
PubMed: 35009945
DOI: 10.3390/s22010386