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Study of Power Consumption of Timepix3 Detector
摘要： The Timepix3 readout chip — the latest member of the Medipix family of hybrid pixel detectors — brought several new functionalities in comparison with the older Timepix, i.e. a high hit-rate, a time granularity of 1.5625 ns, a data-driven readout scheme (with a per pixel dead time of approximately 475 ns), and the capability of measuring Time-over-Threshold (ToT) and Time-of-Arrival (ToA) in each pixel at the same time. However, the high power consumption of the Timepix3 in the standard setting prevents its use in applications with limited power budget. Moreover, the high power consumption poses the risk of overheating the sensor so that proper cooling is crucial. The presented work investigates the effect of different settings in the analogue and a digital part of the Timepix3 detector on its power consumption. Measurements were performed with the Timepix3 chipboard. The firmware of the Katherine readout was modified so that the user can monitor the power consumptions of analogue and digital part “on-line” (directly in the control software). In standard settings, a power consumption of approximately 1.3 W was found. By changes of internal DACs, the consumption could be reduced to 650 mW. Further reduction was achieved by the change of the clock management in the digital part of the Timepix3. In result, a power consumption of 216 mA could be achieved. In these low power settings, the ToA clock was reduced to 10 MHz and thus the time binning was 100 ns. The energy resolution was not affected significantly. The pixel dead time is also negatively affected when the matrix clock is reduced. In the case of 10 MHz, the minimal per pixel dead time is 1.9 μs.
关键词： databases),Detector control systems (detector and experiment monitoring and slow-control systems,Data acquisition concepts,hardware,algorithms,architecture
更新于2025-09-23 15:23:52
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Cuff-less continuous measurement of blood pressure using wrist and fingertip photo-plethysmograms: Evaluation and feature analysis
摘要： Continuous monitoring of blood pressure improves prevention and control of cardiovascular diseases. Currently, cuff-based oscillometric sphygmomanometers are commonly used to monitor the systolic and diastolic blood pressure. However, this technique is discontinuous in nature and inconvenient for repeated measurements. Here we have proposed indirect measurement of blood pressure from photo-plethysmograms (PPG) simultaneously recorded from wrist and fingertip. The signals were recorded from 111 participants and different morphological features were obtained from PPG and its second derivative, acceleration plethysmograms (APG). Moreover, different measures of pulse transit time (PTT) and pulse wave velocity (PWV) were obtained from the recorded PPGs. Multi-layer Neural Networks were used to estimate the non-linear relationship between these features and systolic and diastolic blood pressures (SBP and DBP). Mean absolute errors of 6.77 and 4.82 mmHg were achieved in comparison with measurements from a validated commercial oscillometric sphygmomanometer. Feature analysis provided insight about the importance of features for estimating BP, and demonstrated that these features are not the same for SBP and DBP. Using the highest-ranked 15 and 13 features obtained from moving-backward algorithm the mean absolute errors were reduced to 5.31 and 4.62 mmHg for SBP and DBP. However, the optimum optimal feature sets provided by a genetic algorithm for estimating SBP/DBP led to the lowest mean absolute errors of 4.94/4.03. These results compared to previous studies and the available standards suggest that the method is a promising substitute for oscillometric sphygmomanometers which can be used conveniently for continuous monitoring of blood pressure.
关键词： Genetic algorithms,Non-obstructive blood pressure measurement,Multi-layer neural networks,Photo-plethysmography
更新于2025-09-23 15:23:52
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Performance Analysis of Maximum Power Point Tracking Algorithms Under Varying Irradiation
摘要： Photovoltaic (PV) system is one of the reliable alternative sources of energy and its contribution in energy sector is growing rapidly. The performance of PV system depends upon the solar insolation, which will be varying throughout the day, season and year. The biggest challenge is to obtain the maximum power from PV array at varying insolation levels. The maximum power point tracking (MPPT) controller, in association with tracking algorithm will act as a principal element in driving the PV system at maximum power point (MPP). In this paper, the simulation model has been developed and the results were compared for perturb and observe, incremental conductance, extremum seeking control and fuzzy logic controller based MPPT algorithms at different irradiation levels on a 10.2 kW PV array. The results obtained were analysed in terms of convergence rate and their efficiency to track the MPP.
关键词： perturb and observe,fuzzy logic controller,scalar gradient extremum seeking control,Photovoltaic system,incremental conductance,MPPT algorithms
更新于2025-09-23 15:23:52
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Total polyphenol quantitation using integrated NIR and MIR spectroscopy: A case study of Chinese dates ( <i>Ziziphus jujuba</i> )
摘要： Polyphenols are the foremost measure of phytochemicals in Chinese dates due to their many potential health benefits such as averting cancers, reducing the risk of coronary artery disease, diuretic activity, myocardial stimulant, coronary dilator and muscle relaxant. To quantitate the polyphenols in Chinese dates using a data fusion approach with near‐infrared (NIR) and mid‐infrared (MIR) spectroscopy. A total of 80 Chinese dates samples were used for data acquisition from both NIR and MIR spectroscopy. The efficient spectral intervals were extracted by the synergy interval partial least square (Si‐PLS) algorithm as input variables for NIR‐MIR fusion model. A genetic algorithm (GA) was used to construct the model based on NIR‐MIR fusion. The performance of the developed models was evaluated using correlation coefficients of calibration (R2) and prediction (r2), root mean square error of prediction (RMSEP), bias and residual prediction deviation (RPD). The data fusion model based on the GA was superior compared to NIR and MIR build model. The optimal GA‐fusion model yielded R2 = 0.9621, r2 = 0.9451, RPD = 2.44, calibration set bias = 0.004 and prediction set bias = 0.061, computing only 15 variables. These findings reveal that integration of NIR and MIR is possible for the prediction of total polyphenol content in Chinese dates.
关键词： spectroscopy techniques,polyphenols,genetic algorithms,principal component analysis,spectral interval selection
更新于2025-09-23 15:23:52
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Quantum analog-digital conversion
摘要： Many quantum algorithms, such as the Harrow-Hassidim-Lloyd (HHL) algorithm, depend on oracles that efficiently encode classical data into a quantum state. The encoding of the data can be categorized into two types: analog encoding, where the data are stored as amplitudes of a state, and digital encoding, where they are stored as qubit strings. The former has been utilized to process classical data in an exponentially large space of a quantum system, whereas the latter is required to perform arithmetics on a quantum computer. Quantum algorithms such as HHL achieve quantum speedups with a sophisticated use of these two encodings. In this work, we present algorithms that convert these two encodings to one another. While quantum digital-to-analog conversions have implicitly been used in existing quantum algorithms, we reformulate it and give a generalized protocol that works probabilistically. On the other hand, we propose a deterministic algorithm that performs a quantum analog-to-digital conversion. These algorithms can be utilized to realize high-level quantum algorithms such as a nonlinear transformation of amplitudes of a quantum state. As an example, we construct a 'quantum amplitude perceptron,' a quantum version of the neural network that hence has a possible application in the area of quantum machine learning.
关键词： quantum analog-to-digital conversion,quantum machine learning,quantum algorithms,digital encoding,analog encoding,quantum digital-to-analog conversion
更新于2025-09-23 15:23:52
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Characterisation of Timepix3 with 3D sensor
摘要： Tests were performed at the SPS facilities at CERN using a 40 GeV/c pion beam with prototype 3D-Timepix3 detectors (3D detector). A planar-Timepix3 (planar detector) was placed along the beam axis together with the 3D detectors in a telescope arrangement for comparison and reference. We demonstrate that the combination of 3D-geometry silicon sensors and Timepix3 module can reduce the effect of charge sharing and lowers the carrier drift-time, while giving the same spectroscopy performance without sacrificing the timing or any performance advantages of the Timepix3 module.
关键词： Performance of High Energy Physics Detectors,databases),Detector control systems (detector and experiment monitoring and slow-control systems,hardware,algorithms,architecture
更新于2025-09-23 15:23:52
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[IEEE 2018 XIV International Scientific-Technical Conference on Actual Problems of Electronics Instrument Engineering (APEIE) - Novosibirsk, Russia (2018.10.2-2018.10.6)] 2018 XIV International Scientific-Technical Conference on Actual Problems of Electronics Instrument Engineering (APEIE) - Increase in Accuracy of the Solution of the Problem of Identification of Production Batches of Semiconductor Devices
摘要： Authors provide a comparative analysis of the results of applying various automatic grouping (clustering) algorithms to a problem of separating homogeneous batches of electrical radio products from a mixed batch. Authors consider opportunities of optimizing the algorithm parameters as well as compilation of ensembles of clustering algorithms. The obtained results demonstrate that the homogeneity analysis of batches of the electronic components installed in real space systems is an actual problem, especially in the case of A high level of integration. Authors substantiate the necessity of centralized acquisition of spacecraft equipment on the principle of equal reliability by creating special production batches manufactured for space industry.
关键词： clustering algorithms,space electronics,ensembles of algorithms
更新于2025-09-23 15:22:29
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[IEEE 2018 International Conference and Exposition on Electrical And Power Engineering (EPE) - Iasi (2018.10.18-2018.10.19)] 2018 International Conference and Exposition on Electrical And Power Engineering (EPE) - Metaheuristic Algorithms based Multi-objective Optimization for Image Segmentation
摘要： In this paper a multi-threshold image segmentation procedure based on nature-inspired multi-objective optimization is proposed. The Particle Swarm Optimization, Black Hole and Gravitational Search algorithms were adapted for multi-objective optimization. The Root Mean Square Error and the number of segmented regions were used as optimization criteria. The three procedures were applied for human silhouettes detection in video sequences and the obtained results are compared. Concerning the algorithms performances, the experiments revealed that the results of multi-objective Black Hole algorithm based segmentation are better than those of the other two algorithms, at least for the test images used in this experiment.
关键词： nature-inspired algorithms,human locomotion,video processing,multi-objective optimization
更新于2025-09-23 15:22:29
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[IEEE 2018 IEEE International Conference on Communications, Control, and Computing Technologies for Smart Grids (SmartGridComm) - Aalborg, Denmark (2018.10.29-2018.10.31)] 2018 IEEE International Conference on Communications, Control, and Computing Technologies for Smart Grids (SmartGridComm) - Distributed Cooperative Energy Management in Smart Microgrids with Solar Energy Prediction
摘要： Smart Microgrid (SMG), integrated with renewable energy, energy storage system and advanced bidirectional communication network, has been envisioned to improve efficiency and reliability of power delivery. However, the stochastic nature of renewable energy and privacy concerns due to intensive bidirectional data exchange make the traditional energy management system (EMS) perform poorly. In order to improve operational efficiency and customers’ satisfaction, we propose a distributed cooperative energy management system (DCEMS). We adopt recurrent neural network with long short-term memory to predict the solar energy generation with high accuracy. We then solve the underlying economic dispatch problem with distributed scalable Alternating Direction Method of Multipliers (ADMM) algorithm to avoid single point of failure problem and preserve customers’ privacy. In the first stage, each SMG optimizes its operation decision vector in a centralized manner based on one-day ahead solar energy generation prediction. In the second stage, all SMGs share their energy exchange information with directly connected neighboring SMGs to cooperatively optimize the global operation cost. The proposed DCEMS is deployed in our distributed SMGs emulation platform and its performance is compared with other approaches. The results show that the proposed DCEMS outperforms heuristic rule-based EMS by more than 30%. It can also protect customers’ privacy and avoid single point of failure without degrading performance too much compared to centralized EMS.
关键词： Information prediction,Microgrid emulation platform,Distributed algorithms,Energy management system,Demand-side management
更新于2025-09-23 15:22:29
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[IEEE 2017 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC) - Atlanta, GA (2017.10.21-2017.10.28)] 2017 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC) - Joint Reconstruction of PET Attenuation and Activity from Scattered and Unscattered Data
摘要： In previous work, we have proposed scatter-to-attenuation reconstruction for positron emission tomography (PET). Scatter-to-attenuation reconstruction aims at recovering object attenuation information in the form of spatial electron-density distributions from pairs of coincident photons, one of which has been single-scattered. One idea is to interleave scatter-to-attenuation reconstruction, which inputs an activity distribution and outputs an attenuation map, with trues-to-activity reconstruction, which inputs said attenuation map and outputs an improved activity distribution. However, major uncertainties regarding the applicability of this approach revolve around a) the unknown impact of the initial activity estimate; b) evaluation of reconstructed activity distributions, and c) convergence to the correct solution. Methods: Using low-dimensional simulated PET data (mouse-sized, 18x18-voxels phantom), we start with mostly uniform initial activity and attenuation estimates and iteratively apply maximum-likelihood expectation-maximization (MLEM) and a maximum-likelihood gradient-ascent (MLGA) algorithm to update activity (from unscattered data) and attenuation (from scattered data), respectively. We evaluate results in terms of log-likelihoods of the expected scatter histograms, and normalized mean squared errors with respect to reference image-space distributions of activity and attenuation. Results: In our study, both attenuation and activity converged to the reference distributions, despite MLEM and MLGA starting with incorrect attenuation and activity estimates, respectively. Conclusion: The MLGA scatter-to-attenuation reconstruction algorithm, in combination with MLEM trues-to-activity reconstruction, jointly reconstructs attenuation maps and attenuation-corrected activity distributions from scattered and unscattered coincidences without reliance on a-priori information about the activity distribution.
关键词： image reconstruction,PET,attenuation,Compton scattering,algorithms
更新于2025-09-23 15:22:29