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Leblanc, James
Publications (10 of 49) Show all publications
Ovacikli, A. K., Pääjärvi, P. & Leblanc, J. (2014). Skewness as an objective function for vibration analysis of rolling element bearings (ed.). In: (Ed.), (Ed.), 2013 8th International Symposium on Image and Signal Processing and Analysis (ISPA 2013: Trieste, Italy, 4-6 Sept. 2013. Paper presented at International Symposium on Image and Signal Processing and Analysis : 04/09/2013 - 06/09/2013 (pp. 462-466). Piscataway, NJ: IEEE Communications Society
Open this publication in new window or tab >>Skewness as an objective function for vibration analysis of rolling element bearings
2014 (English)In: 2013 8th International Symposium on Image and Signal Processing and Analysis (ISPA 2013: Trieste, Italy, 4-6 Sept. 2013, Piscataway, NJ: IEEE Communications Society, 2014, p. 462-466Conference paper, Published paper (Refereed)
Abstract [en]

The scale invariant third order moment, skewness, is analysed as an objective function to an adaptive gradient ascent algorithm. The purpose is to achieve a spectrum at the filter output that can enable identification of possible bearing defect signatures which are impulsive and periodic. Harmonically related sinusoids are used to represent such signatures and to build a signal model allowing characterization of the objective surface of skewness, providing insight to its convergent behaviour. The results are supported with an experiment from an industry setting. Robustness of the proposed algorithm is demonstrated by examining the frequency spectrum resulting from the signal model.

Place, publisher, year, edition, pages
Piscataway, NJ: IEEE Communications Society, 2014
National Category
Signal Processing
Research subject
Signal Processing
Identifiers
urn:nbn:se:ltu:diva-31882 (URN)631fe16d-ee34-4da2-aa13-b4b4387e315d (Local ID)9781479931255 (ISBN)631fe16d-ee34-4da2-aa13-b4b4387e315d (Archive number)631fe16d-ee34-4da2-aa13-b4b4387e315d (OAI)
Conference
International Symposium on Image and Signal Processing and Analysis : 04/09/2013 - 06/09/2013
Note
Godkänd; 2014; 20140113 (kubova)Available from: 2016-09-30 Created: 2016-09-30 Last updated: 2017-12-13Bibliographically approved
Ovacikli, K., Pääjärvi, P., Leblanc, J. & Carlson, J. E. (2014). Uncovering harmonic content via skewness maximization: a Fourier analysis (ed.). In: (Ed.), Proceedings of the 22nd European Signal Processing Conference (EUSIPCO 2014): Lisbon, Portugal, 1-5 Sept. 2014. Paper presented at European Signal Processing Conference : 01/09/2014 - 05/09/2014 (pp. 481-485). Piscataway, NJ: IEEE Communications Society, Article ID 6952135.
Open this publication in new window or tab >>Uncovering harmonic content via skewness maximization: a Fourier analysis
2014 (English)In: Proceedings of the 22nd European Signal Processing Conference (EUSIPCO 2014): Lisbon, Portugal, 1-5 Sept. 2014, Piscataway, NJ: IEEE Communications Society, 2014, p. 481-485, article id 6952135Conference paper, Published paper (Refereed)
Abstract [en]

Blind adaptation with appropriate objective function results in enhancement of signal of interest. Skewness is chosen as a measure of impulsiveness for blind adaptation to enhance impacting sources arising from defective rolling bearings. Such impacting sources can be modelled with harmonically related sinusoids which leads to discovery of harmonic content with unknown fundamental frequency by skewness maximization. Interfering components that do not possess harmonic relation are simultaneously suppressed with proposed method. An experimental example on rolling bearing fault detection is given to illustrate the ability of skewness maximization in uncovering harmonic content.

Place, publisher, year, edition, pages
Piscataway, NJ: IEEE Communications Society, 2014
Series
Proceedings of the European Signal Processing Conference (EUSIPCO), ISSN 2076-1465
National Category
Signal Processing
Research subject
Signal Processing
Identifiers
urn:nbn:se:ltu:diva-26816 (URN)0120e785-6998-4ca4-adb0-1e70312841b8 (Local ID)978-0-9928-6261-9 (ISBN)0120e785-6998-4ca4-adb0-1e70312841b8 (Archive number)0120e785-6998-4ca4-adb0-1e70312841b8 (OAI)
Conference
European Signal Processing Conference : 01/09/2014 - 05/09/2014
Note

Godkänd; 2014; 20141120 (kubova)

Available from: 2016-09-30 Created: 2016-09-30 Last updated: 2021-09-09Bibliographically approved
Casselgren, J., Sjödahl, M. & Leblanc, J. P. (2012). Model-based winter road classification (ed.). International Journal of Vehicle Systems Modelling and Testing, 7(3), 268-284
Open this publication in new window or tab >>Model-based winter road classification
2012 (English)In: International Journal of Vehicle Systems Modelling and Testing, ISSN 1745-6436, E-ISSN 1745-6444, Vol. 7, no 3, p. 268-284Article in journal (Refereed) Published
Abstract [en]

An investigation of different road conditions has been conducted using a short-wave infrared (SWIR) light online sensor to examine the possibility of estimating road condition parameters such as porosity, depth and roughness. These parameters are essential for non-contact road friction estimation. The investigation show that it is possible to detect changes of depths of water and ice as well as classify different types of ice, by utilising polarised short-wave infrared (SWIR) light and a modified Hapke directional reflectance model

Keywords
road surface classification, vehicle applications, road friction estimation, optical sensor, safety applications, winter road classification, ice, snow, Väggrepp, Väglagskarakterisering, Väglagsklassificering
National Category
Applied Mechanics Signal Processing
Research subject
Experimental Mechanics; Signal Processing
Identifiers
urn:nbn:se:ltu:diva-9531 (URN)10.1504/IJVSMT.2012.048941 (DOI)2-s2.0-84866262098 (Scopus ID)82f2a1c4-9ec2-48de-ae2a-2e3496ea3d10 (Local ID)82f2a1c4-9ec2-48de-ae2a-2e3496ea3d10 (Archive number)82f2a1c4-9ec2-48de-ae2a-2e3496ea3d10 (OAI)
Projects
CASTT - Centre for Automotive Systems Technologies and Testing
Note

Validerad; 2012; 20110416 (johcas)

Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2022-08-31Bibliographically approved
Pääjärvi, P. & Leblanc, J. (2010). Blind linear equalization of PPM signals using third-order moments (ed.). IEEE Transactions on Wireless Communications, 9(4), 1298-1302
Open this publication in new window or tab >>Blind linear equalization of PPM signals using third-order moments
2010 (English)In: IEEE Transactions on Wireless Communications, ISSN 1536-1276, E-ISSN 1558-2248, Vol. 9, no 4, p. 1298-1302Article in journal (Refereed) Published
Abstract [en]

A novel blind equalization strategy for pulse position modulation (PPM) based on maximizing the third-order moment of the equalizer output is presented. Compared to traditional fourth-order (e.g. kurtosis-based) methods, third-order moments give faster convergence and are less sensitive to noise. This work demonstrates that the intersymbol interference that plagues typical indoor ultra wideband (UWB) channels can be combatted using a third-moment maximizing blind equalizer which could therefore provide a cold start-up for a decision-directed scheme. Adaptation is shown to be asymptotically globally convergent with increasing time-hopped PPM frame length. Simulation experiments compare the performance to standard fourth-order schemes in practical settings, taking into account the conditions of time-hopping,multiple-access interference and a realistic UWB channel model.

National Category
Signal Processing
Research subject
Signal Processing
Identifiers
urn:nbn:se:ltu:diva-10594 (URN)10.1109/TWC.2010.04.091025 (DOI)000276817400010 ()2-s2.0-77951284405 (Scopus ID)96ac6300-5424-11df-a0f4-000ea68e967b (Local ID)96ac6300-5424-11df-a0f4-000ea68e967b (Archive number)96ac6300-5424-11df-a0f4-000ea68e967b (OAI)
Note
Validerad; 2010; 20100430 (ysko)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2018-07-10Bibliographically approved
Pääjärvi, P. & Leblanc, J. (2010). Fault-impact enhancement using adaptive filtering for condition monitoring of ball bearings (ed.). In: (Ed.), (Ed.), The Seventh International Conference on Condition Monitoring and Machinery Failure Prevention Technologies: 22 - 24 June 2010, Ettington Chase, Stratford-upon-Avon, England ; CM 2010/MFPT 2010. Paper presented at International Conference on Condition Monitoring and Machinery Failure Prevention Technologies : 22/06/2010 - 24/06/2010 (pp. 517-527). Northampton: Coxmoor Publishing Co., 1
Open this publication in new window or tab >>Fault-impact enhancement using adaptive filtering for condition monitoring of ball bearings
2010 (English)In: The Seventh International Conference on Condition Monitoring and Machinery Failure Prevention Technologies: 22 - 24 June 2010, Ettington Chase, Stratford-upon-Avon, England ; CM 2010/MFPT 2010, Northampton: Coxmoor Publishing Co. , 2010, Vol. 1, p. 517-527Conference paper, Published paper (Refereed)
Abstract [en]

A new signal pre-processing algorithm for condition monitoring of rolling bearings is presented. By enhancing the statistical asymmetry of a measured vibration signal, it is shown to enhance weak impacts from outer-and inner race defects to aid feature extraction and fault detection. Unlike many popular methods such as the high-frequency resonance technique (e.g. envelope analysis), the proposed algorithm is based solely on linear time-domain processing of lowpass vibration signals and hence does not rely on non-linear processing or on the potentially difficult task of selecting an appropriate frequency band for analysis. Consequently, low computational complexity as well as ease of use and implementation can be obtained. A key feature of the method is the enhancement of fault impulses in noisy and distorted measurement data series. This is accomplished through a novel type of adaptive filtering that selectively enhances transient impulses while simultaneously suppressing noise and disturbances. Numerical results are presented demonstrating the new algorithm applied to accelerometer data from industrial environments

Place, publisher, year, edition, pages
Northampton: Coxmoor Publishing Co., 2010
National Category
Signal Processing
Research subject
Signal Processing
Identifiers
urn:nbn:se:ltu:diva-30950 (URN)4f8a14d4-004f-49d1-8892-0459aa2f33ed (Local ID)9781901892338 (ISBN)4f8a14d4-004f-49d1-8892-0459aa2f33ed (Archive number)4f8a14d4-004f-49d1-8892-0459aa2f33ed (OAI)
Conference
International Conference on Condition Monitoring and Machinery Failure Prevention Technologies : 22/06/2010 - 24/06/2010
Note
Godkänd; 2010; 20140826 (andbra)Available from: 2016-09-30 Created: 2016-09-30 Last updated: 2017-11-25Bibliographically approved
Lycksam, H., Sjödahl, M., Gren, P. & Leblanc, J. (2008). Wiener filtering of interferometry measurements through turbulent air using an exponential forgetting factor (ed.). Applied Optics, 47(16), 2971-2978
Open this publication in new window or tab >>Wiener filtering of interferometry measurements through turbulent air using an exponential forgetting factor
2008 (English)In: Applied Optics, ISSN 1559-128X, E-ISSN 2155-3165, Vol. 47, no 16, p. 2971-2978Article in journal (Refereed) Published
Abstract [en]

The problem of imaging through turbulent media has been studied frequently in connection with astronomical imaging and airborne radars. Therefore most image restoration methods encountered in the literature assume a stationary object, e.g., a star or a piece of land. In this paper the problem of interferometric measurements of slowly moving or deforming objects in the presence of air disturbances and vibrations is discussed. Measurement noise is reduced by postprocessing the data with a digital noise suppression filter that uses a reference noise signal measured on a small stationary plate inserted in the field of view. The method has proven successful in reducing noise in the vicinity of the reference point where the size of the usable area depends on the degree of spatial correlation in the noise, which in turn depends on the spatial scales present in the air turbulence. Vibrations among the optical components in the setup tend to produce noise that is highly correlated across the field of view and is thus efficiently reduced by the filter. © 2008 Optical Society of America.

National Category
Applied Mechanics Signal Processing
Research subject
Experimental Mechanics; Signal Processing
Identifiers
urn:nbn:se:ltu:diva-11365 (URN)10.1364/AO.47.002971 (DOI)000256847300011 ()18516114 (PubMedID)2-s2.0-49649104038 (Scopus ID)a50ebe30-8652-11dd-8275-000ea68e967b (Local ID)a50ebe30-8652-11dd-8275-000ea68e967b (Archive number)a50ebe30-8652-11dd-8275-000ea68e967b (OAI)
Note
Validerad; 2008; 20080919 (ysko)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2021-12-13Bibliographically approved
Casselgren, J., Sjödahl, M. & Leblanc, J. (2007). Angular spectral response from covered asphalt (ed.). Applied Optics, 46(20), 4277-4288
Open this publication in new window or tab >>Angular spectral response from covered asphalt
2007 (English)In: Applied Optics, ISSN 1559-128X, E-ISSN 2155-3165, Vol. 46, no 20, p. 4277-4288Article in journal (Refereed) Published
Abstract [en]

By measuring the spectral reflection from the four different road conditions dry, wet, icy, and snowy asphalt, a method of classification for the different surfaces -- using two and three wavelengths -- is developed. The method is tested against measurements to ascertain the probability of wrong classification between the surfaces. From the angular spectral response, the fact that asphalt and snow are diffuse reflectors and water and ice are reflective are confirmed.

National Category
Applied Mechanics Signal Processing
Research subject
Experimental Mechanics; Signal Processing
Identifiers
urn:nbn:se:ltu:diva-14480 (URN)10.1364/AO.46.004277 (DOI)000247665000011 ()17579683 (PubMedID)2-s2.0-34548482307 (Scopus ID)dda131b0-5aed-11dc-8a1d-000ea68e967b (Local ID)dda131b0-5aed-11dc-8a1d-000ea68e967b (Archive number)dda131b0-5aed-11dc-8a1d-000ea68e967b (OAI)
Projects
CASTT - Centre for Automotive Systems Technologies and Testing
Note
Validerad; 2007; 20070904 (pafi)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2023-09-06Bibliographically approved
Pääjärvi, P. & Leblanc, J. (2007). Blind equalization of PPM signals using third-order moments (ed.). In: (Ed.), (Ed.), 2007 IEEE 8th Workshop on Signal Processing Advances in Wireless Communications: SPAWC 2007, Helsinki, Finland, 17 - 20 June 2007. Paper presented at IEEE Workshop on Signal Processing Advances in Wireless Communications : 17/06/2007 - 20/06/2007. Piscataway, NJ: IEEE Communications Society
Open this publication in new window or tab >>Blind equalization of PPM signals using third-order moments
2007 (English)In: 2007 IEEE 8th Workshop on Signal Processing Advances in Wireless Communications: SPAWC 2007, Helsinki, Finland, 17 - 20 June 2007, Piscataway, NJ: IEEE Communications Society, 2007Conference paper, Published paper (Refereed)
Abstract [en]

In pulse-position modulation (PPM) signaling, the time location of short-duration pulses are used to convey information over a communication channel. For successful noncoherent reception, the channel duration must be short compared to the symbol interval. This paper analyzes the use of third moments in a blind adaptive equalizer setting to limit the effective delay spread of the channel. Results detail the global convergence properties of the proposed method, showing that the parameters approach ISI-free settings under general conditions.

Place, publisher, year, edition, pages
Piscataway, NJ: IEEE Communications Society, 2007
National Category
Signal Processing
Research subject
Signal Processing
Identifiers
urn:nbn:se:ltu:diva-39239 (URN)10.1109/SPAWC.2007.4401370 (DOI)2-s2.0-48049095718 (Scopus ID)de3c88a0-dfc6-11dc-9e29-000ea68e967b (Local ID)978-1-4244-0955-6 (ISBN)de3c88a0-dfc6-11dc-9e29-000ea68e967b (Archive number)de3c88a0-dfc6-11dc-9e29-000ea68e967b (OAI)
Conference
IEEE Workshop on Signal Processing Advances in Wireless Communications : 17/06/2007 - 20/06/2007
Note
Godkänd; 2007; 20080220 (ysko)Available from: 2016-10-03 Created: 2016-10-03 Last updated: 2023-09-06Bibliographically approved
Sehlstedt, M. & Leblanc, J. (2006). A computability strategy for optimization of multiresolution broadcast systems: a layered energy distribution approach (ed.). IEEE transactions on broadcasting, 52(1), 11-20
Open this publication in new window or tab >>A computability strategy for optimization of multiresolution broadcast systems: a layered energy distribution approach
2006 (English)In: IEEE transactions on broadcasting, ISSN 0018-9316, E-ISSN 1557-9611, Vol. 52, no 1, p. 11-20Article in journal (Refereed) Published
Abstract [en]

This paper investigates the possible system gain for a multiresolution broadcast system using multilayer transmission of multiresolution data by utilizing nonuniform layer transmission energies. It shows how to find the energy distribution that maximizes the system performance, measured in the form of a sum of a weighted layer values /spl times/ population product (representing possible revenue for service providers). Through the introduction of the relative population coverage function P(a/sub i/) it is shown for a N layer system that in many cases when P(a/sub i/) is a concave function (equivalent to -P(a/sub i/) being convex) it is possible to reduce what seems to be an N-dimensional problem to N line searches. The paper also shows how the relative population coverage function can be constructed in two ways. The first uses analytic models for signal strength and population coverage (Uniform and Rayleigh). The second uses numerical signal strength and population estimates in grid format. The paper also includes examples to illustrate how the method works and the performance gain it provides. One of the examples uses actual grid estimates for an example transmitter located in Lulea, Sweden.

National Category
Signal Processing
Research subject
Signal Processing
Identifiers
urn:nbn:se:ltu:diva-11515 (URN)10.1109/TBC.2005.857603 (DOI)000235785400002 ()2-s2.0-33644669199 (Scopus ID)a81b07b0-a016-11db-8975-000ea68e967b (Local ID)a81b07b0-a016-11db-8975-000ea68e967b (Archive number)a81b07b0-a016-11db-8975-000ea68e967b (OAI)
Note
Validerad; 2006; 20070109 (ysko)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2023-09-06Bibliographically approved
Pääjärvi, P. & Leblanc, J. (2006). Computationally efficient norm-constrained adaptive blind deconvolution using third-order moments (ed.). In: (Ed.), (Ed.), 2006 IEEE International Conference on Acoustics, Speed [i.e. Speech] and Signal Processing: Toulouse, France, 14 - 19 May 2006. Paper presented at IEEE International Conference on Acoustics, Speech and Signal Processing : 15/05/2006 - 19/05/2006 (pp. 752-755). Piscataway, NJ: IEEE Communications Society, 3
Open this publication in new window or tab >>Computationally efficient norm-constrained adaptive blind deconvolution using third-order moments
2006 (English)In: 2006 IEEE International Conference on Acoustics, Speed [i.e. Speech] and Signal Processing: Toulouse, France, 14 - 19 May 2006, Piscataway, NJ: IEEE Communications Society, 2006, Vol. 3, p. 752-755Conference paper, Published paper (Refereed)
Abstract [en]

Third-order central moments have been shown to be well suited as objective functions for blind deconvolution of impulsive signals. Online implementations of such algorithms may suffer from increasing filter norm, forcing adaptation under constrained filter norm. This paper extends a previously known efficient algorithm with self-stabilizing properties to the case of using a third-order moment objective function. New results herein use averaging analysis to determine adaptation stepsize conditions for asymptotic stability of the filter norm.

Place, publisher, year, edition, pages
Piscataway, NJ: IEEE Communications Society, 2006
Series
I E E E International Conference on Acoustics, Speech and Signal Processing. Proceedings, ISSN 1520-6149
National Category
Signal Processing
Research subject
Signal Processing
Identifiers
urn:nbn:se:ltu:diva-33128 (URN)10.1109/ICASSP.2006.1660763 (DOI)2-s2.0-33947622544 (Scopus ID)7eb24240-9660-11db-8975-000ea68e967b (Local ID)1-424-40468-1 (ISBN)7eb24240-9660-11db-8975-000ea68e967b (Archive number)7eb24240-9660-11db-8975-000ea68e967b (OAI)
Conference
IEEE International Conference on Acoustics, Speech and Signal Processing : 15/05/2006 - 19/05/2006
Note
Validerad; 2006; 20061228 (ysko)Available from: 2016-09-30 Created: 2016-09-30 Last updated: 2023-10-06Bibliographically approved
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