| 1. |
- Alickovic, Emina, et al.
(författare)
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Ensemble SVM Method for Automatic Sleep Stage Classification
- 2018
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - : IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC. - 0018-9456 .- 1557-9662. ; 67:6, s. 1258-1265
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Tidskriftsartikel (refereegranskat)abstract
- Sleep scoring is used as a diagnostic technique in the diagnosis and treatment of sleep disorders. Automated sleep scoring is crucial, since the large volume of data should be analyzed visually by the sleep specialists which is burdensome, time-consuming tedious, subjective, and error prone. Therefore, automated sleep stage classification is a crucial step in sleep research and sleep disorder diagnosis. In this paper, a robust system, consisting of three modules, is proposed for automated classification of sleep stages from the single-channel electroencephalogram (EEG). In the first module, signals taken from Pz-Oz electrode were denoised using multiscale principal component analysis. In the second module, the most informative features are extracted using discrete wavelet transform (DWT), and then, statistical values of DWT subbands are calculated. In the third module, extracted features were fed into an ensemble classifier, which can be called as rotational support vector machine (RotSVM). The proposed classifier combines advantages of the principal component analysis and SVM to improve classification performances of the traditional SVM. The sensitivity and accuracy values across all subjects were 84.46% and 91.1%, respectively, for the five-stage sleep classification with Cohens kappa coefficient of 0.88. Obtained classification performance results indicate that, it is possible to have an efficient sleep monitoring system with a single-channel EEG, and can be used effectively in medical and home-care applications.
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| 2. |
- Alizadeh, Mahmoud, et al.
(författare)
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Measurement and Analysis of Frequency-Domain Volterra Kernels of Nonlinear Dynamic 3 x 3 MIMO Systems
- 2017
-
Ingår i: IEEE Transactions on Instrumentation and Measurement. - : IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC. - 0018-9456 .- 1557-9662. ; 66:7, s. 1893-1905
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Tidskriftsartikel (refereegranskat)abstract
- Multiple-input multiple-output (MIMO) frequencydomain Volterra kernels of nonlinear order 3 are experimentally determined in bandwidth-limited frequency regions. How the effect of higher nonlinear orders can be reduced and how this affects the estimated errors are discussed. The magnitude and the phase of the kernels are Kramers-Kronig consistent. The self-kernels and cross-kernels have different symmetries, and the kernels are therefore determined and analyzed in different regions in the 3-D frequency space. By analyzing the properties along certain paths in the 3-D frequency space, the block structures for the respective kernels are determined. These block structures contain the significant blocks of the general block structures for the third-order kernels. The device under test is an MIMO transmitter for radio frequency signals.
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| 3. |
- Alizadeh, Mahmoud, et al.
(författare)
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Measurement and analysis of frequency-domainVolterra kernels of nonlinear dynamic 3x3 MIMO systems
- 2016
-
Ingår i: IEEE Transactions on Instrumentation and Measurement. - : IEEE Press. - 0018-9456 .- 1557-9662.
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Tidskriftsartikel (refereegranskat)abstract
- Multiple-input multiple-output (MIMO) frequency-domain Volterra kernels of nonlinear order 3 are experimentally determined in bandwidth-limited frequency regions. How the effect of higher nonlinear orders can be reduced and how this affects the estimated errors are discussed. The magnitude and phase of the kernels areKramers-Kronig consistent. The self- and cross-kernels have different symmetries and the kernels are therefore determined and analyzed in different regions in the 3D frequency space. By analyzing the properties along certain paths in the 3D frequency space, the block structures for the respective kernels are determined. These block structures contain the significant blocks of the general block structures for third-order kernels. The device under test is a MIMO transmitter for radio frequency signals.
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| 4. |
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| 5. |
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| 6. |
- Amin, Shoaib, et al.
(författare)
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Characterization of concurrent dual-band Power Amplifiers using a dual two-tone excitation signal
- 2015
-
Ingår i: IEEE Transactions on Instrumentation and Measurement. - : IEEE Press. - 0018-9456 .- 1557-9662. ; :99
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Tidskriftsartikel (refereegranskat)abstract
- A method to characterize the memory effects in a nonlinear concurrent dual-band transmitter is presented. It is an extension of the conventional two tone test for power amplifiers to concurrent dual band transmitters. The output signal of a concurrent dual-band transmitter is affected not only by intermodulation products but also by cross-modulation products. In one frequency band, the transmitter is excited by a two tone signal which frequency separation is swept. In the second band the transmitter is concurrently excited by an other two tone signal with slightly wider frequency separation. The frequency difference of the two signals is fixed during the frequency sweep. The two tone test is made at different power levels. The upper and lower third-order inter- and cross-modulation products are measured. The asymmetry between the upper and lower third-order inter- and cross-modulation products are measures of the transmitter's memory effects. The measurement results show that the memory effects are more dominant in the third-order intermodulation products than in the cross modulation products. An error analysis and system calibration was performed and measurement results for two different devices are presented.
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| 7. |
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| 8. |
- Andersen, Olav, et al.
(författare)
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Extending the Bandwidth and Dynamic Range of Old RF Instruments to Meet State-of-the-Art Performance, Using a Synthetic Instrument Approach
- 2009
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - 0018-9456 .- 1557-9662. ; 58:2, s. 248-254
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Tidskriftsartikel (refereegranskat)abstract
- A decrease in life cycle cost is a key issue for testing mobile communication systems. The rapid development and edge technology requires high-performance instruments and state-of-the-art measurement technology. New investments are expensive, but even older generation instruments are capable of extending their bandwidth and dynamic range to meet even the latest Third-Generation Partnership Project (3GPP) cellular measurement requirements by the addition of external hardware using a synthetic instrument approach. The novelty of this paper is the high performance on the most crucial parameters, i.e., the dynamic range and bandwidth achieved by only replacing some parts of the legacy instrument. Moreover, the demonstrated direct IF synthesis has a high degree of novelty at wide modulation bandwidths. It is desired to use virtual/synthetic instruments and make the signal processing in the software independent of the hardware, i.e., software-defined measurements (SDMs). In this paper, a state-of-the-art experimental setup for signal generation and signal analysis is demonstrated. A direct IF synthesis is used to generate a wideband code-division multiple-access (WCDMA) carrier with more than 72-dB adjacent carrier leakage ratio (ACLR) up to 12 parallel carriers with more than 68-dBc ACLR over a total bandwidth of 100 MHz. The signal analysis capabilities (e.g., ACLR performance) for a WCDMA carrier is better than -70 dBc and for a continuous wave better than -85 dBc over a bandwidth of 42.5 MHz. The critical RF downconverter in the setup is carefully designed not to degrade the dynamic range performance.
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| 9. |
- Andersson, Tomas, et al.
(författare)
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IEEE standard 1057, Cramer-Rao bound and the parsimony principle
- 2006
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - : Institute of Electrical and Electronics Engineers (IEEE). - 0018-9456 .- 1557-9662. ; 55:1, s. 44-53
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Tidskriftsartikel (refereegranskat)abstract
- This paper deals with some fundamental properties of the sine-wave-fit algorithm included in IEEE Standards 1057 and 1241. Asymptotic Cramer-Rao bounds (CRBs) for three and four model parameters are derived under the Gaussian assumption. Further, the sine-wave-fitting properties of the algorithm are analyzed by the parsimony principle. A decision criterion whether to use the three- or four-parameter model is derived. It is shown that a three-parameter sine-wave fit produces a better fit than the four-parameter fit if the frequency is known to be within an interval related to the number of samples and the signal-to-noise ratio. By a numerical analysis, the theoretical results are shown to be also valid for the uniform noise model of quantization.
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| 10. |
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| 11. |
- Aranda, Jesus Javier Lechuga, et al.
(författare)
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An Apparatus For The Performance Estimation Of Pressure Fluctuation Energy Harvesters
- 2018
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - : IEEE. - 0018-9456 .- 1557-9662. ; 67:11, s. 2705-2713
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Tidskriftsartikel (refereegranskat)abstract
- Hydraulic pressure fluctuation energy harvesters are promising alternatives to power up wireless sensor nodes in hydraulic systems. The characterization of these harvesters under dynamic and band-limited pressure signals is imperative for the research and development of novel concepts. To generate and control these signals in a hydraulic medium, a versatile apparatus capable of reproducing pressure signals is proposed. In this paper, a comprehensive discussion of the design considerations for this apparatus and its performance is given. The suggested setup enables the investigation of devices tailored for the harvesting of energy in conventional hydraulic systems. To mimic these systems, static pressures can be tuned up to 300 bar, and the pressure amplitudes with a maximum of 28 Bar at 40 Hz and 0.5 bar at 1000 Hz can be generated. In addition, pressure signals found in commercial hydraulic systems can be reproduced with good accuracy. This apparatus proves to be an accessible, robust, and versatile experimental setup to create environments for the complete performance estimation of pressure fluctuation energy harvesters.
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| 12. |
- Ascorti, Leonardo, et al.
(författare)
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A Wireless Cloud Network Platform for Industrial Process Automation : Critical Data Publishing and Distributed Sensing
- 2017
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - 0018-9456 .- 1557-9662. ; 66:4, s. 592-603
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Tidskriftsartikel (refereegranskat)abstract
- Wireless technologies combined with advanced computing are changing industrial communications. Industrial wireless networks can improve the monitoring and the control of the entire system by jointly exploiting massively interacting communication and distributed computing paradigms. In this paper, we develop a wireless cloud platform for supporting critical data publishing and distributed sensing of the surrounding environment. The cloud system is designed as a self-contained network that interacts with devices exploiting the time synchronized channel hopping protocol (TSCH), supported by WirelessHART (IEC 62591). The cloud platform augments industry-standard networking functions as it handles the delivery (or publishing) of latency and throughput-critical data by implementing a cooperative-multihop forwarding scheme. In addition, it supports distributed sensing functions through consensus-based algorithms. Experimental activities are presented to show the feasibility of the approach in two real industrial plant sites representative of typical indoor and outdoor environments. Validation of cooperative forwarding schemes shows substantial improvements compared with standard industrial solutions. Distributed sensing functions are developed to enable the autonomous identification of recurring cochannel interference patterns.
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| 13. |
- Barac, Filip, et al.
(författare)
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Scrutinizing Bit- and Symbol-Errors of IEEE 802.15.4 Communication in Industrial Environments
- 2014
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - 0018-9456 .- 1557-9662. ; 63:7, s. 1783-1794
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Tidskriftsartikel (refereegranskat)abstract
- The knowledge of error nature in wireless channels is an essential constituent of efficient communication protocol design. To this end, this paper is the first comprehensive bit- and symbol-level analysis of IEEE 802.15.4 transmission errors in industrial environments. The intention with this paper is to extract the error properties relevant for future improvements of wireless communication reliability and coexistence of radio systems in these harsh conditions. An extensive set of bit-error traces was collected in a variety of scenarios and industrial environments, showing that error behavior is highly dependent on the cause of packet corruption. It is shown that errors inflicted by multipath fading and attenuation exhibit different properties than those imposed by IEEE 802.11 interference. The statistical behavior of these two patterns is concurrently investigated in terms of differences in bit-error distribution, error burst length, channel memory length, and the scale of packet corruption. With these conclusions at hand, abiding to the computational constraints of embedded sensors and the statistical properties of bit-errors, a Reed-Solomon $(15,k)$ block code is chosen to investigate the implications of bit-error nature on practical aspects of channel coding and interleaving. This paper is concluded by a number of findings of high practical relevance, concerning the optimal type, depth, and meaningfulness of interleaving.
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| 14. |
- Barbé, Kurt, et al.
(författare)
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A Simple Nonparametric Preprocessing Technique to Correct for Nonstationary Effects in Measured Data
- 2012
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - 0018-9456 .- 1557-9662. ; 61:8, s. 2085-2094
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Tidskriftsartikel (refereegranskat)abstract
- The general approach for modeling systems assumes that the measured signals are (weakly) stationary, i.e., the power spectrum is time invariant. However, the stationarity assumption is violated when: 1) transient effects due to experimental conditions are dominant; 2) data are missing due to, for instance, sensor failure; or 3) the amplitude of the excitation signals smoothly varies over time due to, for instance, actuator problems. Although different methods exist to deal with each of these nonstationary effects specifically, no unified approach is available. In this paper, a new and general technique is presented to handle nonstationary effects, based on processing overlapping subrecords of the measured data. The proposed method is a simple preprocessing step where the user does not need to specify which nonstationary effect is present, nor the time interval where the nonstationary effect appears. The merits of the proposed approach are demonstrated on an operational wireless system suffering from interrupted link effects.
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| 15. |
- Bastos, M. C., et al.
(författare)
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A high-voltage test bed for the evaluation of high-voltage dividers for pulsed applications
- 2011
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - 0018-9456 .- 1557-9662. ; 60:7, s. 2462-2468
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Tidskriftsartikel (refereegranskat)abstract
- The design, evaluation, and commissioning of a high-voltage reference test bed for pulsed applications to be used in the precision testing of high-voltage dividers is described. The test bed is composed of a pulsed power supply, a reference divider based on compressed-gas capacitor technology, and an acquisition system that makes use of the fast measurement capabilities of the HP3458 digital voltmeter. The results of the evaluation of the reference system are presented. © 2006 IEEE.
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| 16. |
- Baumann, N., et al.
(författare)
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Piepser 2.0 : A Self-Sustaining Smartwatch to Maximize the Paragliders Flytime
- 2020
-
Ingår i: IEEE Transactions on Instrumentation and Measurement. - : Institute of Electrical and Electronics Engineers Inc.. - 0018-9456 .- 1557-9662. ; 69:4, s. 1445-1454
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Tidskriftsartikel (refereegranskat)abstract
- The main motivation of paraglider pilots is to stay in the air for as long as possible. Therefore, paraglider pilots are always searching for thermal upwind that allow them to gain altitude. These thermal lifts are difficult to detect. Therefore, sensors and devices that indicate the vertical speed (so-called variometers) are widely used among paraglider pilots. This article presents the design and the implementation of an ultralow-power, self-sustaining, high-precision, wrist-worn variometer with a minimal form factor but infinite lifetime, which can visually and acoustically indicate the vertical velocity. This article demonstrates the benefits of combining multisource energy harvesting (EH) for wearable devices with low power design, exploiting a novel near-threshold ARM Cortex-M4F microcontroller, the Ambiq Apollo2, for the onboard processing. The experimental results show a power consumption of only 17.12~\mu \text{W} in sleep mode and 1937.21~\mu \text{W} in the worst case scenario when processing the data and outputting an audio feedback. Measurements confirmed that combining both thermal and solar EH makes the designed electronics self-sustaining. Without EH, the system will be operational for up to 372 h in always-on mode (worst case scenario) supplied by a 200-mAh lithium-ion battery. © 1963-2012 IEEE.
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| 17. |
- Beltramelli, Luca, et al.
(författare)
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Energy efficiency of slotted LoRaWANcommunication with out-of-band synchronization
- 2021
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - 0018-9456 .- 1557-9662.
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Tidskriftsartikel (refereegranskat)abstract
- Although the idea of using wireless links for covering large areas is not new, the advent of Low Power Wide area networks (LPWANs) has recently started changing the game. Simple, robust, narrowband modulation schemes permit the implementation of low-cost radio devices offering high receiver sensitivity, thus improving the overall link budget. The several technologies belonging to the LPWAN family, including the well-known LoRaWAN solution, provide a cost-effective answer to many Internet-of-things (IoT) applications, requiring wireless communication capable of supporting large networks of many devices (e.g., smart metering). Generally, the adopted medium access control (MAC) strategy is based on pure ALOHA, which, among other things, allows to minimize the traffic overhead under constrained duty cycle limitations of the unlicensed bands. Unfortunately, ALOHA suffers from poor scalability, rapidly collapsing in dense networks. This work investigates the design of an improved LoRaWAN MAC scheme based on slotted ALOHA. In particular, the required time dissemination is provided by out-of-band communications leveraging on Radio Data System(FM-RDS) broadcasting, which natively covers wide areas both indoor and outdoor. An experimental setup based on low-cost hardware is used to characterize the obtainable synchronization performance and derive a timing error model. Consequently, improvements in success probability and energy efficiency have been validated by means of simulations in very large networks with up to 10000 nodes. It is shown that the advantage of the proposed scheme over conventional LoRaWAN communication is up to 100% when short update time and large payload are required. Similar results are obtained regarding the energy efficiency improvement, that is close to 100% for relatively short transmission intervals and long message duration; however, due to the additional overhead for listening the time dissemination messages, efficiency gain can be negative for very short duration of message fastly repeating.
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| 18. |
- Bergman, Anders, et al.
(författare)
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A Constant Voltage Source Based on a Mercury Battery
- 1993
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - : Institute of Electrical and Electronics Engineers (IEEE). - 0018-9456 .- 1557-9662. ; 42:2, s. 365-367
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Tidskriftsartikel (refereegranskat)abstract
- A constant voltage source based on a stable mercury battery has been developed at SP (Swedish National Testing and Research Institute). By using as active current compensation technique, the inherent high stability of a mercury battery can be retained up to a load current of several milliamperes.
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| 19. |
- Bergman, Sixten, et al.
(författare)
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New reference measurement system for calibration of VLF high voltage
- 2011
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - 0018-9456 .- 1557-9662. ; 60:7, s. 2422-2426
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Tidskriftsartikel (refereegranskat)abstract
- A reference measuring system for 200 kV from very low frequencies (0.1 Hz, VLF) up to 50 Hz based on traditional high-voltage components, such as compressed gas capacitors, has been developed and verified. The verification of the measuring system has been performed by two experimental methods, one directly measuring the scale factor and one using measurements over the frequency and voltage range of the components of the measuring system. The frequency dependence of the measuring system proved to be one of the dominating uncertainties and was extensively researched. Proper correction for known errors and estimation of uncertainty contributions proved that traceable measurement of VLF voltage can be made with an uncertainty of less than 0.038% up to a voltage of 200 kV. This measurement service has been notified to be included in SP entries for Bureau International des Poids et Mesures key comparison database and can serve an important need for the cable industry. © 2006 IEEE.
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| 20. |
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| 21. |
- Bergsten, Tobias, et al.
(författare)
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An Active Filter for Delta-Sigma-Modulated Josephson Waveforms
- 2015
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - 0018-9456 .- 1557-9662. ; 64:6, s. 1559-1563
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Tidskriftsartikel (refereegranskat)abstract
- We present the design and electrical characteristics of an active low-pass filter. It will be used in a reference waveform source based on a programmable Josephson voltage standard with multilevel delta-sigma modulation to generate accurate and spectrally pure arbitrary waveforms. The filter has a fifth-order Butterworth characteristic with high input impedance, low distortion, high stopband attenuation, and stable passband performance, including dc.
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| 22. |
- Bergsten, Tobias, et al.
(författare)
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Realization of Absolute Phase and AC Resistance of Current Shunts by Ratio Measurements
- 2019
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - 0018-9456 .- 1557-9662. ; 68:6, s. 2041-2046
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Tidskriftsartikel (refereegranskat)abstract
- This paper presents a simplified method for realizing absolute phase and ac resistance for current shunts using only impedance ratio measurements. The method is based on three geometrically identical current shunts with different resistances, but with the same inductance, capacitance, and ac-dc resistance change of resistance at ac compared to dc). We demonstrate how the inductance, capacitance, and ac resistance can be calculated from the complex impedance ratio measurements, therefore realizing absolute current shunt impedance. The method gives competitive uncertainties of around 200 μΩ/Ω for amplitude and 400 μrad for phase at 1 MHz in the 1-Ω range.
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| 23. |
- Björsell, Niclas, et al.
(författare)
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Histogram Tests for Wideband Applications
- 2008
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - 0018-9456 .- 1557-9662. ; 57:1, s. 70-75
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Tidskriftsartikel (refereegranskat)abstract
- Characterization and testing of analog-to-digital converters (ADCs) are important for many reasons. A histogram test is a common method to characterize the linearity features of an ADC. Two commonly used stimulus signals are sine waves and Gaussian noise. This paper presents a metrological comparison between Gaussian and sine-wave histogram tests for wide-band applications, that is, we evaluate the performance of the characterization of the ADC and the usability of postcorrection. A postcorrection procedure involves the characterization of the ADC nonlinearity and then the use of this information by processing the ADC output samples to remove the distortion. The results show that the Gaussian histogram test gives reasonable accuracy in measuring nonlinearities. However, it does not result in a suitable model for postcorrection in wideband applications. A single-tone sine-wave histogram will be a better basis for postcorrection. The best result can be obtained if the lookup table is trained with several single-tone sine waves in the frequency band.
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| 24. |
- Björsell, Niklas, et al.
(författare)
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Measuring Volterra Kernels of Analog To Digital Converters Using a Stepped Three-Tone Scan
- 2008
-
Ingår i: IEEE Transactions on Instrumentation and Measurement. - 0018-9456 .- 1557-9662. ; 57:4, s. 666-671
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Tidskriftsartikel (refereegranskat)abstract
- The Volterra theory can be used to mathematically model nonlinear dynamic components such as analog-to-digital converters (ADCs). This paper describes how frequency-domain Volterra kernels of an ADC are determined from measurements. The elements of the Volterra theory are given, and practical issues are considered, such as methods for signal conditioning and finding the appropriate test signals scenario and suitable sampling frequency. The results show that, for the used pipeline ADC, the frequency dependence is significantly stronger for second-order difference products than for sum products and the linear frequency dependence was not as pronounced as that of the second-order Volterra kernel. It is suggested that the Volterra kernels have the symmetry properties of a specific box model, namely, the parallel Hammerstein system.
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| 25. |
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| 26. |
- Båvall, Lennart
(författare)
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Determination of coating thickness of a copper-plated steel wire by measurement of the internal wire impedance
- 1998
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - : Institute of Electrical and Electronics Engineers (IEEE). - 0018-9456 .- 1557-9662. ; 47:4, s. 1013-1019
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Tidskriftsartikel (refereegranskat)abstract
- A measurement of the internal impedance of a copper-cladded steel wire by a quote measurement of the voltage across and current through the wire can be used as a method to determine the cladding thickness. An electromagnetic model accounting for the internal impedance with different values of the coating thickness on a steel wire is described. Numerical calculations based on this model have been carried out and compared with measurements. An example shows how the method can be used to model a steel wire with a coating of copper to find the expected impedance as a function of coating thickness
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| 27. |
- Båvall, Lennart, 1945-
(författare)
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Determination of thickness of silver coatings on brass by measuring the impedance of a thin elliptic coil
- 2007
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - 0018-9456 .- 1557-9662. ; 56:3, s. 790-799
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Tidskriftsartikel (refereegranskat)abstract
- To measure the impedance of a thin elliptically shaped coil, in presence of a flat plate with a coat of metal, can be an instrument for determination of the cladding thickness. An electromagnetic field from the coil is then forced to the object, producing eddy currents inside the object. These are influenced by the characteristics of the object and the coil and give rise to an impedance change, which can be detected and correlated to the thickness of the coating. An electromagnetic model accounting for the impedance of the elliptic coil with different values on the numerical eccentricity and the coating thickness is described. The model is based on a dyadic Green function formulation of the problem from which the electric field and hence the impedance is evaluated by utilizing the method of scattering super position. Numerical calculations based on the model and experimental measurements have been taken. An example shows how the model can be used to model a brass surface with a coat of silver to find expected impedance as function of the coating thickness
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| 28. |
- Capriglione, D., et al.
(författare)
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Experimental Analysis of Filtering Algorithms for IMU-Based Applications under Vibrations
- 2021
-
Ingår i: IEEE Transactions on Instrumentation and Measurement. - : Institute of Electrical and Electronics Engineers Inc.. - 0018-9456 .- 1557-9662. ; 70
-
Tidskriftsartikel (refereegranskat)abstract
- The use of microelectro-mechanical systems (MEMS)-based inertial measurement units (IMUs) is widespread in many applications concerning monitoring, diagnostic, and/or controlling in navigation and transportation systems, as well as in low-cost applications for automotive and aeronautical fields. The data provided by the set of sensors typically present in IMUs, as accelerometers, gyroscopes, and magnetometers, are often used also for feeding suitable filtering and positioning algorithms able to correct the attitude and path of the vehicle on which they are installed or to provide the analytical redundancy needed for online diagnosis. Nevertheless, on one hand, the performance of low-cost MEMS-based IMUs is certified only under a small set of nominal operating conditions, and on the other hand, the filtering algorithms are often designed and verified under canonical additive noises. In this framework, this article proposes a test plan and a test setup for analyzing and characterizing the performance of filtering algorithms for positioning based on data coming from low-cost IMUs and able to verify systematically the operation of such algorithms under real scenarios. Two kinds of very popular filtering algorithms have been considered, namely, the complementary filter and the attitude and heading reference systems (AHRS) Kalman filter, which belong to two opposite approaches. The experimental results prove how the typical vibrations present in real scenarios can significantly affect the performance of such algorithms. © 1963-2012 IEEE.
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| 29. |
- Capriglione, D., et al.
(författare)
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Soft Sensors for Instrument Fault Accommodation in Semiactive Motorcycle Suspension Systems
- 2020
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - : Institute of Electrical and Electronics Engineers Inc.. - 0018-9456 .- 1557-9662. ; 69:5, s. 2367-2376
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Tidskriftsartikel (refereegranskat)abstract
- This article describes the development and experimental verification of an instrument fault accommodation (IFA) scheme for front and rear suspension stroke sensors in motorcycles equipped with electronically controlled semiactive suspension systems. In particular, the IFA scheme is based on the use of nonlinear autoregressive with exogenous inputs (NARX) neural networks (NNs) employed as soft sensors for feeding the suspension control strategy back with measurement even in the presence of faults occurred on the sensors. Different NN architectures have been trained and tuned by considering real data acquired during several measurement campaigns. The performance has been compared with that of the well-known half-car model (HCM). Very satisfying results allow the soft sensor to be really integrated into fault-tolerant control systems. In experimental road tests, an implementation of the proposed IFA scheme on a low-cost microcontroller for automotive applications showed to be in real time. In this article, these experimental results are shown to prove the good performance of the IFA scheme in different motorcycle operating conditions. © 1963-2012 IEEE.
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| 30. |
- Caro, D. Di, et al.
(författare)
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Hazelnut Oil Classification by NMR Techniques
- 2017
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - 0018-9456 .- 1557-9662. ; 66:5, s. 928-934
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Tidskriftsartikel (refereegranskat)abstract
- Nuclear magnetic resonance (NMR) has been widely used in chemical analysis and medical diagnosis. In recent years, thanks to the development of the NMR instrumentation and the software for data analysis, it is becoming a useful tool for quality control in the food industry. In this field, several applications have been developed related to the compositional and structural analysis, authentication, packaging, and on-line monitoring. This paper highlights the capability of NMR to discern between the oil extracted from healthy and unhealthy hazelnuts, as a preliminary step toward the automatic detection of the hidden defects in full hazelnuts. Different processing techniques are analyzed on the CPMG response in order to set up the final measurement system.
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| 31. |
- Catelani, Marcantonio, et al.
(författare)
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Optimizing Maintenance Policies for a Yaw System Using Reliability-Centered Maintenance and Data-Driven Condition Monitoring
- 2020
-
Ingår i: IEEE Transactions on Instrumentation and Measurement. - : IEEE. - 0018-9456 .- 1557-9662. ; 69:9, s. 6241-6249
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Tidskriftsartikel (refereegranskat)abstract
- System downtime and unplanned outages massively affect plant productivity; therefore, the reliability, availability, maintainability, and safety (RAMS) disciplines, together with fault diagnosis and condition monitoring (CM), are mandatory in energy applications. This article focuses on the optimization of a maintenance plan for the yaw system used in an onshore wind turbine (WT). A complete reliability-centered maintenance (RCM) procedure is applied to the system to identify which maintenance action is the optimal solution in terms of cost, safety, and availability. The scope of the research is to propose a new customized decision-making diagram inside the RCM assessment to reduce the subjectivity of the procedure proposed in the standard and save the cost by optimizing maintenance decisions, making the projects more cost-efficient and cost-effective. This article concludes by proposing a new diagnostic method based on a data-driven CM system to efficiently monitor the health and detect damages in the WT by means of measurements of critical parameters of the tested system. This article highlights how a reliability analysis, during the early phase of the design, is a very helpful and powerful means to guide the maintenance decision and the data-driven CM.
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| 32. |
- Chang, Lin, et al.
(författare)
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Multisurface Interferometric Algorithm and Error Analysis With Adaptive Phase Shift Matching
- 2022
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - : IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC. - 0018-9456 .- 1557-9662. ; 71
-
Tidskriftsartikel (refereegranskat)abstract
- To simultaneously measure topographies of both surfaces of a transparent plate through wavelength-tuning interferometry at arbitrary cavity lengths, a flexible phase shift matching algorithm (FPSMA) is proposed. The FPSMA includes two parts: 1) taking the four-term third-order Nuttall window as an example, a phase demodulation approach is designed and analyzed for extracting the harmonic phases of the front surface, rear surface, and thickness variation of the measured plate and 2) based on the residual error analysis of the developed 5N-Nuttall algorithm for different cavity length coefficients M and the phase-shifting parameters N , a parameter-change technique that allows the developed phase demodulation approach is applied to arbitrary cavity lengths by adaptively changing the phase shifts and frames of the captured interferograms. By this technique, the algorithm failures due to the spectral aliasing of harmonics can be avoided effectively and conveniently, and then the correct phase demodulation can be ensured. Besides, using the developed method, when the values of N or M are chosen in advance, the corresponding available measurement ranges can be given. Besides, the relationship between the window length and the measurement limitation of the measurable thinnest optical thickness is investigated. Considering the common linear and nonlinear errors in the wavelength-shifting process, the error analysis of FPSMA is performed and discussed for situations close to reality. The comparative studies and the experimental results of two transparent parallel plates also support the performance of the developed FPSMA.
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| 33. |
- Cheng, Liu, et al.
(författare)
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EEG-CLNet : Collaborative Learning for Simultaneous Measurement of Sleep Stages and OSA Events Based on Single EEG Signal
- 2023
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - : IEEE. - 0018-9456 .- 1557-9662. ; 72
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Tidskriftsartikel (refereegranskat)abstract
- Sleep-stage and apnea-hypopnea index (AHI) are the most important metrics in the diagnosis of sleep syndrome disease. In previous studies, these two tasks are usually implemented separately, which is both time- and resource-consuming. In this work, we propose a novel single electroencephalogram (EEG)-based collaborative learning network (EEG-CLNet) for simultaneous sleep staging and obstructive sleep apnea (OSA) event detection through multitask collaborative learning. The EEG-CLNet regards different tasks as a common unit to extract features from intragroups via both local parameter sharing and cross-task knowledge distillation (CTKD), rather than just sharing parameters or shortening the distance between different tasks. Our approach has been validated on two datasets with the same or better performance than other methods. The experimental results show that our method achieves a performance gain of 1%-5% compared with the baseline. Compared to previous works where two or even more models were required to perform sleep staging and OSA event detection, the EEG-CLNet could reduce the total number of model parameters and facilitate the model to mine the hidden relationships between different task semantic information. More importantly, it effectively alleviates the task bias problem in hard parameter sharing. As a consequence, this approach has notable potential to be a solution for a lightweight wearable sleep monitoring system in the future.
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| 34. |
- Cheng, Peng, et al.
(författare)
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A Local Positioning System for Loader Cranes Based on Wireless Sensors-A Feasibility Study
- 2011
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - 0018-9456 .- 1557-9662. ; 60:8, s. 2881-2893
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Tidskriftsartikel (refereegranskat)abstract
- This paper presents a feasibility study that deals with a local positioning system for a loader crane based on battery-powered wireless sensors and consists of two joint angular sensors and one telescopic boom length ranger. The practical challenges associated with using conventional sensors are described in order to provide the motivation behind the choice to use the sensing methods proposed in this paper. A novel method is tested using microelectromechanical system inertial sensors mounted around the crane joints to indirectly measure the joint angles, as well as an ultrasound time-of-flight ranging method to measure the telescopic boom length. The local positioning system's wireless sensor prototype designs are described in detail. Data from the angular sensor experiments conducted on a loader crane and the ultrasound ranging experiments conducted both in the laboratory and on the loader crane are presented and analyzed. The preliminary results from these experiments show that the performance of the new sensors is promising. The conclusion is drawn from the experimental results, and future work for this local positioning system is also described.
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| 35. |
- Cheng, Peng, et al.
(författare)
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Contactless Rotor RPM Measurement Using Laser Mouse Sensors
- 2012
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - 0018-9456 .- 1557-9662. ; 61:3, s. 740-748
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Tidskriftsartikel (refereegranskat)abstract
- This paper presents an experimental study using laser mouse sensors for the contactless revolutions per minute (RPM) measurement of a rotating shaft. The sensor performance characterization experiment is firstly conducted under different parameter setups. After the optimal parameter value has been found, the rotor RPM experiment is then conducted with a speed sweep from 500 to 3800 rpm, and data are gathered at 30 different speeds and processed using two different methods to convert the sensor readings into the RPM of the rotating shaft; the results are then displayed. The performance differences between the two methods are compared, and the observation is that both the linearity and the signal-to-noise ratio of the frequency correlation method are several times better than those for the amplitude correlation method. The conclusion summarizes the experimental results and the advantage associated with this new RPM sensing method and provides the motivation for its potential applications and its future works.
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| 36. |
- Cheng, Peng, et al.
(författare)
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Design and Implementation of a Stator-Free RPM Sensor Prototype Based on MEMS Accelerometers
- 2012
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - 0018-9456 .- 1557-9662. ; 61:3, s. 775-785
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Tidskriftsartikel (refereegranskat)abstract
- This paper presents the design and implementation of a prototype of a stator-free revolutions-per-minute (RPM) sensor based on two microelectromechanical-system uniaxial accelerometers. This paper first introduces the operating principle of the stator-free RPM sensor. It then discusses the associated architecture and design issues of this new sensing method. It then describes the detail of the prototype sensor hardware and software design of the common-mode rejection method and its signal processing. Experiments using the prototype sensor have been also conducted to further verify and strengthen the arguments put forward in the previous discussion. All experiments in this paper took place on a lathe machine in a laboratory. Sensor calibration under a MATLAB environment is also described. Experimental results confirm the interesting property of this sensor, namely, that it provides higher precision at higher RPM. The conclusion summarizes the design considerations, the experimental results, and the motivation in relation to future works for this stator-free RPM sensing method.
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| 37. |
- Cheng, Peng, et al.
(författare)
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Joint-angle Measurement Using Accelerometers and Gyroscopes : A Survey
- 2010
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - 0018-9456 .- 1557-9662. ; 59:2, s. 404-414
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Tidskriftsartikel (refereegranskat)abstract
- This paper presents an analysis of rigid-body joint-angle measurement based on microelectromechanical-system (MEMS) biaxial accelerometers and uniaxial gyroscopes. In comparison to conventional magnetic and optical joint angular sensors, this new inertial sensing principle has the advantages of flexible installation and true contactless sensing. This paper focuses on the comparison of four different inertial-sensor combination methods that are reported in reference papers and utilizes the theory of rigid-body kinematics to explain and analyze their advantages and weaknesses. Experiments have also been conducted to further verify and strengthen the arguments put forward in the analysis. All experiments in this paper took place on a custom-built rigid-body robot arm model that can be manipulated by hand. Sensor calibration and accelerometer alignment issues are also described, and their details are discussed. The experiment results presented in this paper show significant differences with reference to the achieved angular accuracy for various situations when using the four different sensor combination methods. In some cases, the angular error based on one method is more than 0.04 rad, while that from another method is within +/-0.005 rad. The noise levels of angular readings from different methods are also experimentally compared and analyzed. The conclusion drawn serves to guide readers toward a suitable method for their particular application.
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| 38. |
- Crema, Claudio, et al.
(författare)
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Virtual Respiratory Rate Sensors : An Example of A Smartphone-Based Integrated and Multiparametric mHealth Gateway
- 2017
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - 0018-9456 .- 1557-9662. ; 66:9, s. 2456-2463
-
Tidskriftsartikel (refereegranskat)abstract
- In the last few years, several wearables appeared in the market, for fitness and healthcare applications. Such smart devices have been proposed as a possible solution for lowering the costs of healthcare, leading to the mHealth revolution. In the typical scenario, each wearable, embedding sensors, processing units and communication modules, adopts a smartphone for data collection, data displaying, and remote communication. In this paper, authors modify this paradigm simplifying the wearables (e.g., relying only on simple analog front ends and communication interfaces) and exploiting the (relatively large) computational capability of the smartphone, not only for implementing gateway features but also for processing raw biosignals as well. Several experiments verify the feasibility of the proposed approach and demonstrate that 'local' biosensor virtualization is possible, expanding possibilities of mHealth. In particular, tests have been carried out to evaluate the performance of hearth rate computation and respiratory rate virtual sensor, starting from a single-lead electrocardiogram signal.
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| 39. |
- De Angelis, Alessio, et al.
(författare)
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A Low-Cost Ultra-Wideband Indoor Ranging System
- 2009
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - 0018-9456 .- 1557-9662. ; 58:12, s. 3935-3942
-
Tidskriftsartikel (refereegranskat)abstract
- This paper presents the development of a low-cost indoor ranging technique based on time-of-arrival (TOA) estimation, using short-pulse ultra-wideband (UWB) signals. The realized system includes two identical UWB transceiver devices, in which the receiver section is based on a tunnel diode detector and the pulse generation is performed by a common bipolar transistor driven in avalanche mode. An indirect measurement of the distance between the devices is obtained by measuring the frequency of the generated pulse train. A theoretical model of the system is described, and a statistical analysis is presented, including the closed-form evaluation of the Cramer-Rao lower bound (CRLB) on the distance estimation and showing the asymptotic statistical efficiency of the proposed estimators. Furthermore, the principle of operation of the realized system prototypes is described, along with some implementation issues. Finally, experimental results are shown and discussed.
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| 40. |
- De Angelis, Alessio, et al.
(författare)
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A Vector Approach for Image Quality Assessment and Some Metrological Considerations
- 2009
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - 0018-9456 .- 1557-9662. ; 58:1, s. 14-25
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Tidskriftsartikel (refereegranskat)abstract
- The main purpose of this paper is to present a metrology-based view of the image quality assessment (IQA) field. Three main topics are developed. First, the state of the art in the field of IQA is presented, providing a classification of some of the most important objective and subjective IQA methods. Then, some aspects of the field are analyzed from a metrological point of view, also through a comparison with the software quality measurement area. In particular, a statistical approach to the evaluation of the uncertainty for IQA objective methods is presented, and the topic of measurement modeling for subjective IQA methods is analyzed. Finally, a vector approach for full-reference IQA is discussed, with applications to images corrupted by impulse and Gaussian noise. For these applications, the vector root mean squared error (VRMSE) and fuzzy VRMSE are introduced. These vector parameters provide a possible way to overcome the main limitations of the mean-squared-error-based IQA methods.
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| 41. |
- De Angelis, Alessio, et al.
(författare)
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Characterization and Modeling of an Experimental UWB Pulse-Based Distance Measurement System
- 2009
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - 0018-9456 .- 1557-9662. ; 58:5, s. 1479-1486
-
Tidskriftsartikel (refereegranskat)abstract
- This paper presents a distance-measuring system based on the accurate round-trip time-of-flight measurement of single ultrawideband pulses propagating between two transceiver devices. The architectures of two realized devices, which are referred to as the master and the slave, are described. The master device implements the time-interval measuring function by means of a time-to-digital converter (TDC) integrated circuit, whereas the slave acts as a pulse repeater. Both devices are designed for low-cost realization and low-power operations. Furthermore, two pulse-detection modules are described based on signal-threshold and energy detection, respectively. This paper also presents and discusses some experimental results that are obtained from the system prototype. Finally, some numerical simulation results, which provide an explanation for the nonidealities in the observed distance-measuring behavior of the system, are shown.
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| 42. |
- De Angelis, Alessio, et al.
(författare)
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Characterization of a Flexible UWB Sensor for Indoor Localization
- 2013
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - 0018-9456 .- 1557-9662. ; 62:5, s. 905-913
-
Tidskriftsartikel (refereegranskat)abstract
- This paper presents research to develop an ultrawideband ranging sensor for personnel indoor localization based on the measurement of the pulse round-trip time. An approach combining flexibility, a high measurement update rate, and asynchronous operation with digital processing capability has been employed in the design of the sensor. The principle of operation, the architecture of the realized sensor, and the experimental setup are described. Finally, the results of a ranging calibration and validation test are presented and discussed. In the validation procedure, a root-mean-square error of 29 cm and a maximum absolute error of 81 cm with an operational range of approximately 10 m were observed.
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| 43. |
- De Angelis, Alessio, et al.
(författare)
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Experimental Comparison of Low-Cost Sub-Nanosecond Pulse Generators
- 2011
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - 0018-9456 .- 1557-9662. ; 60:1, s. 310-318
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper, six low-cost pulse generator devices having sub-nanosecond transition time are analyzed and compared. Some of the possible applications for these devices are also described, along with an overview of the different approaches for sub-nanosecond pulse generation. Furthermore, the architecture and principle of operation of the realized prototypes are explained. The considered pulse generation techniques are based on logic gates, Step-Recovery Diodes, and transistors driven in the avalanche region. Some experimental results obtained by using an equivalent-time sampling oscilloscope and a spectrum analyzer are shown and discussed, providing both a time-domain and a frequency-domain characterization of the prototypes. Finally, an approach for the generation of modulated pulses in the 6-GHz band (for ultra-wideband applications) is investigated, and experimental results are provided.
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| 44. |
- De Angelis, Alessio, et al.
(författare)
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Performance Assessment of Chirp-Based Time Dissemination and Data Communications in Inductively Coupled Links
- 2017
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - 0018-9456 .- 1557-9662. ; 66:9, s. 2474-2482
-
Tidskriftsartikel (refereegranskat)abstract
- Advantages of inductively coupled links for short-range communications are well known. Recently, they gained popularity as a viable solution for wireless power transmission. Interesting to notice that data communication capability is required as well, mainly for coordinating the transfer process. In this paper, the authors address the use of chirp signaling over inductively coupled links for both time dissemination and data communications. Such an approach extends field of applications, including data acquisition and instrumentation that are used in industrial automation. The effectiveness of the proposed approach is verified with extensive simulations and using a proof-of-concept prototype. Despite the prototype simplicity, jitter on the synchronizing reference signal is in the order of few microseconds and the bit error rate, over a short distance, is negligible.
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| 45. |
- de la O Serna, Jose Antonio, et al.
(författare)
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Using alternating Kalman filtering to analyze oscillometric blood pressure waveforms
- 2013
-
Ingår i: IEEE Transactions on Instrumentation and Measurement. - 0018-9456 .- 1557-9662. ; 62:10, s. 2621-2628
-
Tidskriftsartikel (refereegranskat)abstract
- Measuring the blood pressure as accurately as possible can save a lot of human lives. Hence, it is very important to find an optimal method to determine the systolic and diastolic pressures out of the measured oscillometric blood pressure waveform (OBPW). Recently, studies have shown that by working in the frequency domain, outperforming results could be obtained for the separation of breathing from cardiac activity. In this paper, we present a new implementation of the Kalman filtering algorithm to estimate the envelope of the cardiac activity. Even though the alternating Kalman filter algorithm has subharmonic infiltrations, it offers an envelope that, when applied together with the Windkessel model for calibration, substantially reduces the error of the calibrated systolic and diastolic pressures. This important result validates the non-linear model for the OBPW, as well as the Windkessel model for calibration.
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| 46. |
- De Vito, Luca, et al.
(författare)
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Bayesian calibration of a lookup table for ADC error correction
- 2007
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - 0018-9456 .- 1557-9662. ; 56:3, s. 873-878
-
Tidskriftsartikel (refereegranskat)abstract
- This paper presents a new method for the correction of nonlinearity errors in analog-to-digital converters (ADCs). The method has been designed to allow a self-calibration in systems where an internal signal can be generated, such as base stations for mobile communications. The method has been implemented and tested in simulation on the behavioral model of commercial ADCs and on a hardware setup composed by a data acquisition board and a distorting circuit.
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| 47. |
- Di Caro, D., et al.
(författare)
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Quality Assessment of the Inshell Hazelnuts Based on TD-NMR Analysis
- 2020
-
Ingår i: IEEE Transactions on Instrumentation and Measurement. - : Institute of Electrical and Electronics Engineers Inc.. - 0018-9456 .- 1557-9662. ; 69:6, s. 3770-3779
-
Tidskriftsartikel (refereegranskat)abstract
- Nondestructive testing is critical in the quality detection of products. Among several techniques, time-domain nuclear magnetic resonance (TD-NMR) is gaining attention in the field of food quality control, thanks to its ability to detect liquid and solid materials, which are strictly related to the quality of some kinds of products. In this article, a novel method for the inline quality evaluation of the inshell hazelnuts, based on TD-NMR analysis, is disclosed. Different studies have been carried out on the quality control of hazelnuts or, more in general, shell fruit. They usually focus on laboratory application and the analysis of a single physical property. Conversely, the proposed method focuses on the signal processing with the aim of reducing the execution time making the procedure suitable for an inline application. Moreover, the main hidden defects are analyzed together to identify the defective nuts from the good ones in a two-class classification procedure. © 1963-2012 IEEE.
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| 48. |
- Ebenhag, Sven-Christian, 1976, et al.
(författare)
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Measurements and Error Sources in Time Transfer Using Asynchronous Fiber Network
- 2010
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - 1557-9662 .- 0018-9456. ; 59:7, s. 1918-1924
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Tidskriftsartikel (refereegranskat)abstract
- We have performed time transfer experiments basedon passive listening in fiber optical networks using Packet over synchronous optical networking (SONET)/synchronous digital hierarchy(SDH). The experiments have been performed with differentcomplexity and over different distances. For assessmentof the results, we have used a GPS link based on carrier-phase observations. On a 560-km link, precision that is relative to the GPS link of
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| 49. |
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| 50. |
- Ekström, Martin, 1980-, et al.
(författare)
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A Bluetooth Radio Energy Consumption Model for Low Duty-Cycle Applications
- 2012
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Ingår i: IEEE Transactions on Instrumentation and Measurement. - 0018-9456 .- 1557-9662. ; 61:3, s. 609-617
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Tidskriftsartikel (refereegranskat)abstract
- This paper presents a realistic model of the radio energy consumption for Bluetooth-equipped sensor nodes used in a low-duty-cycle network. The model is based on empirical energy consumption measurements of Bluetooth modules. This model will give users the possibility to optimize their radio communication with respect to energy consumption while sustaining the data rate. This paper shows that transmission power cannot always be directly related to energy consumption. Measurements indicate that, when the transmission power ranges from $-$5 to $+$10 dBm, the difference in consumed energy can be detected for each transmission peak in the sniff peak. However, the change is negligible for the overall energy consumption. The nonlinear behavior of the idle state for both master and slave when increasing the interval and number of attempts is presented. The energy consumption for a master node is in direct relation to the number of slaves and will increase by approximately 50% of the consumption of one slave per additional slave, regardless of the radio setting.
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