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  • 1.
    Berrebi, Jonathan
    et al.
    Luleå tekniska universitet.
    Martinsson, Pär-Erik
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Willatzen, M.
    University of Southern Denmark.
    Delsing, Jerker
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Ultrasonic flow metering errors due to pulsating flow2004In: Flow Measurement and Instrumentation, ISSN 0955-5986, E-ISSN 1873-6998, Vol. 15, no 3, p. 179-185Article in journal (Refereed)
    Abstract [en]

    Transit-time ultrasonic flow meters present some advantages over other flow meters for district heating industries. They are both accurate and non-intrusive. It is well-known that ultrasonic flow meters are sensitive to installation effects. Installation effects could be static or dynamic. Among the possible dynamic installation effects is pulsating flow. The influence of pulsating flow on the prediction and the zero-crossing operations is investigated. Expressions are found for the prediction error and the zero-crossing error. The relative errors due to the prediction and the zero-crossing are plotted. The prediction error can reach dramatic values while the zero-crossing operation is hardly influenced by flow pulsations.

  • 2.
    Carlson, Johan
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Birk, Wolfgang
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Martinsson, Pär-Erik
    Löfqvist, Torbjörn
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Håkansson, Mikael
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Castano, Miguel
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Linder, Tomas
    Projekt: SCOPE Norra2011Other (Other (popular science, discussion, etc.))
    Abstract [sv]

    SCOPE Norra är ett samarbetskonsortium för forskning och utveckling tillsammans med massa- och pappersindustrin i Norrbotten och Västerbotten. Projektet koordineras av centrumbildningen ProcessIT Innovations.Inom SCOPE Norra pågår ett flertal delprojekt, uppdelat på ett antal fokusområden.Huvudfinansiär för konsortiet är Tillväxtverket genom medel från EU:s strukturfonder.

  • 3.
    Carlson, Johan
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Martinsson, Pär-Erik
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    A simple scattering model for measuring particle mass fractions in multiphase flows2002In: Ultrasonics, ISSN 0041-624X, E-ISSN 1874-9968, Vol. 39, no 8, p. 585-590Article in journal (Refereed)
    Abstract [en]

    In this paper we present a simple theoretical model of how pulsed ultrasound is attenuated by the particles in a solid/liquid flow. The theoretical model is then used to predict the attenuation of sound, given the mass fraction, the density, and the size distribution of the solid particles. The model is verified experimentally for suspensions of 0–10% (by mass) Dolomite ((Ca,Mg)CO3) particles and water. The experimental results show that the attenuation of sound due to particles varies linearly with mass fraction, and that the proposed theoretical model can be used to predict this attenuation. In all experiments the transmitter and receiver array were clamped onto the pipe wall, thus providing a completely non-invasive and non-intrusive measurement technique.

  • 4.
    Carlson, Johan
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Martinsson, Pär-Erik
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Exploring interaction effects in two-component gas mixtures using orthogonal signal correction of ultrasound pulses2005In: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 117, no 5, p. 2961-2968Article in journal (Refereed)
    Abstract [en]

    Within Sweden and the EU, an increased use of biogas gas and natural gas is encouraged to decrease emission of carbon dioxide. To support more effective manufacturing, distribution, and consumption of energy gases, new methods for the measurement of the calorimetric value or the gas composition are needed. This paper presents a method to extract and visualize variations in ultrasound pulse shape, caused by interaction effects between the constituents of a two-component gas mixture. The method is based on a combination of principal component analysis and orthogonal signal correction. Pulse-echo ultrasound experiments on mixtures of oxygen and ethane in the concentration range from 20% to 80% ethane show that the extracted information could be correlated with the molar fraction of ethane in the mixture

  • 5.
    Carlson, Johan
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Martinsson, Pär-Erik
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Ultrasonic measurement of molar fractions in gas mixtures by orthogonal signal correction2004In: 2004 IEEE Ultrasonics Symposium: 23 - 27 August 2004, Palais des Congrès, Montréal, Canada ; a conference of the IEEE Ultrasonics, Ferroelectrics, and Frequency Control Society (UFFC-S) ; [part of IEEE International Ultrasonics, Ferroelectrics, and Frequency Control 50th Anniversary Joint Conference] / [ed] Marjorie Passini Yuhas, Piscataway, NJ: IEEE Communications Society, 2004, p. 821-825Conference paper (Refereed)
    Abstract [en]

    Within Sweden and the EU, an increased use of biogas and natural gas is encouraged. To support more effective manufacturing, distribution, and consumption of energy gases, new methods for the measurement of the calorimetric value or the gas composition are needed. In this paper, we present a method to quantify variation in ultrasound pulse shape, caused by interaction effects between the constituents of a two-component gas mixture. The method is based on a combination of principal component analysis and orthogonal signal correction. Experiments on mixtures of oxygen and ethane show that the extracted information correlates well with the molar fraction of ethane in the mixture.

  • 6.
    Carlson, Johan
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Sjöberg, Frank
    Luleå tekniska universitet.
    Martinsson, Pär-Erik
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    A noise-tolerant group delay estimator applied to dispersion measurement in gases2003In: Proceedings, 2003 IEEE Ultrasonics Symposium: October 5 - 8, 2003, Hilton Hawaiian Village, Honolulu, Hawaii ; an international symposium / / [ed] Donald E. Yuhas, Piscataway, NJ: IEEE Communications Society, 2003, p. 254-257Conference paper (Refereed)
    Abstract [en]

    In this paper we present a model-based group velocity estimator, that can be used to measure speed of sound in ultrasonic pulse-echo systems as a function of ultrasound frequency. The estimation of group velocities involves numerical differentiation of the phase difference. In the presence of noise, this becomes numerically unstable. The model-based approach presented herein, shows better tolerance to experimental noise. The performance of the estimator is evaluated with simulations as function of pulse bandwidth and SNR. Finally, the estimator applied to real data and compared with other methods for measuring speed of sound in Ethane and Oxygen.

  • 7.
    Eliasson, Jens
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Kyusakov, Rumen
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Martinsson, Pär-Erik
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    An internet of things approach for intelligent monitoring of conveyor belt rollers2013In: 10th International Conference on Condition Monitoring and Machinery Failure Prevention Technologies 2013, CM 2013 and MFPT 2013, 2013, Vol. 2, p. 1096-1104Conference paper (Refereed)
  • 8.
    Johansson, Jonny
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Martinsson, Pär-Erik
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Delsing, Jerker
    Simulation of absolute amplitudes of ultrasound signals using equivalent circuits2007In: IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, ISSN 0885-3010, E-ISSN 1525-8955, Vol. 54, no 10, p. 1977-1983Article in journal (Refereed)
    Abstract [en]

    Equivalent circuits for piezoelectric devices and ultrasonic transmission media can be used to cosimulate electronics and ultrasound parts in simulators originally intended for electronics. To achieve efficient systemlevel optimization, it is important to simulate correct, absolute amplitude of the ultrasound signal in the system, as this determines the requirements on the electronics regarding dynamic range, circuit noise, and power consumption.This paper presents methods to achieve correct, absolute amplitude of an ultrasound signal in a simulation of a pulse-echo system using equivalent circuits. This is achieved by taking into consideration loss due to diffraction and the effect of the cable that connects the electronics and the piezoelectric transducer. The conductive loss in the transmission line that models the propagation media of the ultrasound pulse is used to model the loss due to diffraction.Results show that the simulated amplitude of the echo follows measured values well in both near and far fields, with an offset of about 10%. The use of a coaxial cable introduces inductance and capacitance that affect the amplitude of a received echo. Amplitude variations of 60% were observed when the cable length was varied between 0.07 m and 2.3 m, with simulations predicting similar variations. The high precision in the achieved results show that electronic design and system optimization can rely on system simulations alone. This will simplify the development of integrated electronics aimed at ultrasound systems.

  • 9.
    Martinsson, Pär-Erik
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Calculation of temperature dependency of acoustic properties of diatomic gases using spectroscopic data2003In: Proceedings, 2003 IEEE Ultrasonics Symposium: October 5 - 8, 2003, Hilton Hawaiian Village, Honolulu, Hawaii ; an international symposium / [ed] Donald E. Yuhas, Piscataway, NJ: IEEE Communications Society, 2003, Vol. 2, p. 1471-1474Conference paper (Refereed)
    Abstract [en]

    This paper describes how optical spectroscopic constants can be used to calculate the speed of sound as a function of temperature in diatomic gases. A general expression for the speed of sound is derived by using the vibrational partition function of the gas. The presented method was evaluated for oxygen and nitrogen. The results are in good agreement with the measured data.

  • 10.
    Martinsson, Pär-Erik
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Characterization of energy gases by ultrasound: theory and experiments2004Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The long-term goal with the research presented in this thesis has been to develop an ultrasonic sensor capable of measuring the energy content of energy gases such as natural- and biogas. The energy content can be calculated if the concentration of each constituent of a gas mixture is known. The acoustic properties of a gas mixture are dependent on its composition and by measuring, for example, the speed of sound it is possible to draw conclusions about the composition of the gas mixture. This feature could for instance be built into an ultrasonic flow meter. Natural gas manufactured from a single well is usually very consistent in its composition. However, the gas composition might vary between different wells and therefore also the energy content of the gas. This has the consequence that the quality of a gas might fluctuate if gases from different sources are mixed together. Therefore, the energy content of the gas mixture needs to be monitored in order to assure the quality of the gas. The physical principal that makes ultrasound suitable for gas measurements is called molecular relaxation. At certain frequencies this is the dominating source of acoustic attenuation and dispersion in gases. The frequency region at which the relaxation occurs differs between gases. This feature makes it possible to extract information about the composition of a gas from an ultrasonic pulse that has propagated through the gas. In a gas the molecules are constantly in motion. The molecules have also rotational and vibrational energy levels excited and the temperature determines the equilibrium between external and internal motion. An ultrasonic pulse transmitted trough the gas disturbs the equilibrium between the external and internal modes. This is due to the fact that a pressure pulse locally increases the velocity of the gas molecules, which is equivalent to an increase in temperature. This generates a flow of energy from the translational mode to the internal modes and the pulse is therefore attenuated. In order to design an ultrasonic energy meter there is number of problems that has to be considered. The frequency region where the relaxation effect is dominant has to be determined in order to maximize the variation of measured parameters as function of gas composition. These frequency regions can be found from theoretical predictions or by performing experiments. Many external factors will affect the performance of an energy meter situated \textit{in-situ}. It is important to be able to differ between effects generated by actual variations in gas composition from variations generated by other factors, for example, temperature variations and contamination in the flow. Before an energy meter can be manufactured, simulations has to be done \textit{a priori} in order to design the meter. Such a simulation must consider the electronics of the measurement system and the physics of the acoustic wave propagation through the gas. Much of the useful information wanted is found as variations in the frequency spectra of speed and attenuation of sound. Hence, the ability to measure the frequency dependent speed and attenuation accurate from pulses must be mastered. Further more, ultrasonic pulses are attenuated rapidly in many gases. Therefore, the signal-to-noise ratio can be very low. Is it still possible to extract the useful information even for such pulses? In the thesis different problems concerning gas measurements and modeling is addressed. The research has resulted in a model for temperature dependency of the speed of sound in gases. The model that is applicable to ideal gases has been derived by statistical thermodynamics. Measurement results of the frequency dependency of acoustic properties of gases are presented. Diffraction effects present in the ultrasonic measurement system have been simulated with equivalent circuits. It is shown how pulse shape distortions between pulses that have traveled through different samples of gas can be used as a mean for statistical gas classification. A method for calculating the speed of sound from noisy measurements has been derived. The thesis consists of two parts. The second part contains seven papers that describe the research. The first part serves as an introduction, and a survey, to some of the research problems described in Part II.

  • 11.
    Martinsson, Pär-Erik
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Improved modeling of ultrasonic systems: feasible for industrial applications2002Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    In this thesis tree aspects of ultrasonic measurement and modelling techniques have been investigated. Namely, transducer diffraction modelling using equivalent circuits, wave propagation in multi phase flow, and wave propagation in gases. The work is relevant both from an scientific point of view and from an engineering point of view. It is of importance in all fields of science and engineering to accurately understand, and create simple and yet physically significant models and methods, of complex systems. The goal with the research have been to create a deeper understanding of complex ultrasonic systems, including transducers and wave propagation. This is a prerequisite when designing and constructing ultrasonic measurement systems.

  • 12.
    Martinsson, Pär-Erik
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Carlson, Johan
    Investigating the feasibility of using principal component analysis for ultrasonic classification of gas mixtures2003In: Proceedings, 2003 IEEE Ultrasonics Symposium: October 5 - 8, 2003, Hilton Hawaiian Village, Honolulu, Hawaii ; an international symposium / [ed] Donald E. Yuhas, Piscataway, NJ: IEEE Communications Society, 2003, p. 1396-1399Conference paper (Refereed)
    Abstract [en]

    On-line measurement of the energy content of natural gas is of interest for both industry and customers, since the energy content determines its monetary value. Experiments with pulsed ultrasound show that, in addition to changes in speed of sound and acoustic attenuation, there is also a change in the shape of the sound waveform. In this paper, we investigate the feasibility of using principal component analysis (PCA) to quantify this change in pulse shape. The principle is evaluated for pure oxygen, pure ethane, and mixtures of the two, for different pressures. The results show that by using PCA, it is possible to distinguish between pulses that have propagated through oxygen from pulses in ethane and mixtures of the two.

  • 13.
    Martinsson, Pär-Erik
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Carlson, Johan
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Carlson, R.E.
    Tromsø University.
    Ultrasonic classification of gases using principal component analysis2003In: 5th world congress on ultrasonics WCU 2003, Paris: Institut Biomedical des Cordeliers, Université Pierre et Marie Curie , 2003, p. 1129-1132Conference paper (Refereed)
    Abstract [en]

    On-line measurement of the energy content of natural gas is of interest for both industry and customers, since the energy content determines its monetary value. Experiments with pulsed ultrasound show that, in addition to changes in speed of sound and acoustic attenuation, there is also a change in the shape of the sound waveform. In this paper we investigate the feasibility of using Principal Component Analysis (PCA) to quantify this change in pulse shape. The principle is evaluated for Oxygen and Ethane, for different pressures and different temperatures. The results show that by using PCA, it is possible to distinguish between pulses that have propagated through Oxygen from pulses in Ethane.

  • 14.
    Martinsson, Pär-Erik
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Delsing, Jerker
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Ultrasonic measurements of molecular relaxation in ethane and carbon monoxide2002In: Proceedings: 2002 IEEE Ultrasonics Symposium : October 8 - 11, 2002, Forum Hotel, Munich, Germany; an international symposium / [ed] Donald E. Yuhas, Piscataway, NJ: IEEE Communications Society, 2002, p. 511-516Conference paper (Refereed)
    Abstract [en]

    This paper describes how molecular relaxation can be measured using ultrasound. The velocity and absorption of sound varies with frequency due to molecular relaxation. By measuring these variation the relaxation strength and the effective relaxation time for singular relaxations can be calculated. This paper describes initial measurements performed in order to survey the sound properties in gases both experimentally and theoretically.

  • 15.
    Martinsson, Pär-Erik
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Johansson, Jonny
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Incorporation of diffraction effects in simulations of ultrasonic systems using PSpice models2001In: Proceedings: 2001 IEEE Ultrasonics Symposium : October 7 - 10, 2001, Omni Hotel, Atlanta, Georgia ; an international symposium / [ed] Donald E. Yuhas, Piscataway, NJ: IEEE Communications Society, 2001, p. 405-410Conference paper (Refereed)
    Abstract [en]

    The use of PSpice models for piezoelectric devices and ultrasonic transmission media is of major importance in the design of electronics for ultrasonic systems. Today, these models include viscoelastic loss but disregard loss due to diffraction, i.e. beam spreading. This paper presents a method to include diffraction loss in PSpice simulations of ultrasonic systems. The conductive loss in the transmission line, that models the propagation media of the ultrasound pulse, is used to model the loss due to diffraction. Parameter variations for the piezoelectric device can affect the result greatly. Thus, a sensitivity analysis for the simulation model is presented. Measurements and simulations have been performed using a pulse echo system in water. Maximum distance to the reflector was 200 mm. The piezoelectric devices used were PZ-27 crystals with diameters 6 mm and 12 mm, with a center frequency of 4 MHz. Results show that the simulated amplitude of the echo follows measured values well in both near and far fields, with an offset of about 10%

  • 16.
    Nikolakopoulos, George
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Gustafsson, Thomas
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Martinsson, Pär-Erik
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems. ProcessIT Innovations.
    Andersson, Ulf
    Mine Tek HB, Kiruna.
    A Vision of Zero Entry Production Areas in Mines2015Article in journal (Refereed)
    Abstract [en]

    This industrial article aims in presenting a short roadmap on the identified activities and technologies needed towards the vision of zero entry production areas in Mines. This work has been performed in close cooperation with large mining companies in Europe as part of the Smart Mine of the Future Research, Development and Innovation Program and will present the most important areas that it is expected the robotic technology to have an impact on.

  • 17.
    Pikkarainen, Harri V S
    et al.
    Kemi-Tornio University of Applied Sciences, Technology, Optical Measurement Laboratory.
    Vähäoja, Pekka O.
    University of Oulu, Department of Mechanical Engineering, Machine Design Laboratory.
    Martinsson, Pär-Erik
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Gylling, Arne
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Distance- Spanning Technology.
    Larsson, Anders O.
    Rubico AB, Luleå.
    On-line solid debris analysis of oil using vision technology on open computing platform2009In: 6th International Conference on Condition Monitoring and Machinery Failure Prevention Technologies 2009: Dublin; Ireland; 23 June 2009 - 25 June 2009, 2009, Vol. 1, p. 320-331Conference paper (Refereed)
    Abstract [en]

    This article describes a case-study related to on-line condition monitoring measurements in process industry. A platform for on-line, real-time and remotely operated condition monitoring has been developed. The system consists of an open source based embedded and cost effective DSP computing platform, a machine vision sensor for solid debris analysis of oils, and interfaces for other measurement technologies (e.g. vibration analysis and/or temperature measurements). In addition, the platform is equipped with data transmission interface that enables remote operation and control. Real-time analysis of solid particles in oil is useful in many preventive condition monitoring applications, for example, in the lubrication circuit of a paper machine or with cold rolling lubrication oils. In the case of a paper machine the generated information can be used to pinpoint upcoming failures in the machine elements (e.g. bearings, gears etc.). Whereas in the case of cold rolling applications the information is useful to prevent quality problems in the rolled metal product. In the both applications the presented system enables also monitoring failures in the filtration system. Preliminary results and designs show that the system is able to detect and analyse size and shape for particles larger than 50 micrometers continuously with a frame rate of 5 Hz from the oil flow volume of 13.8 ml/s and flow speed of 60 mm/s. The system is in progress of being further developed in collaboration with the industry. Easy integration of different sensors and real-time measurements make the system a powerful tool for making maintenance decisions in process industry

1 - 17 of 17
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