| 1. |
- Chilo, José, et al.
(författare)
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Obtaining "images" from iron objects using a 3-axis fluxgate magnetometer
- 2007
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 580:2, s. 1105-1109
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Tidskriftsartikel (refereegranskat)abstract
- Magnetic objects can cause local variations in the Earth's magnetic field that can be measured with a magnetometer. Here we used triaxial magnetometer measurements and an analysis method employing wavelet techniques to determine the "signature" or "fingerprint" of different iron objects. Clear distinctions among the iron samples were observed. The time-dependent changes in the frequency powers were extracted by use of the Morlet wavelet corresponding to frequency bands from 0.1 to 100 Hz. (c) 2007 Elsevier B.V. All rights reserved.
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| 2. |
- Ferrer-Coll, Javier, et al.
(författare)
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Analysis of wireless communications in underground tunnels for industrial use
- 2012
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Ingår i: IECON 2012 - 38th Annual Conference on IEEE Industrial Electronics Society. - New York : IEEE conference proceedings. - 9781467324212 - 9781467324199 ; , s. 3216-3220
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Konferensbidrag (refereegranskat)abstract
- Wireless communication is expected to improve the safety and the productivity in underground tunnels for industrial use. However the multiple shapes and structures of tunnels affect wireless communication characteristics in terms of signal propagation which is significantly different from terrestrial environments. This paper presents comprehensive broadband measurements and simulations of multipath propagation and path loss in two underground environments. The results can be used in the development of new communication systems in tunnels that provide industrial services.
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| 3. |
- Ferrer-Coll, Javier, et al.
(författare)
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Antenna Cross Correlation and Ricean -Factor Measurements in Indoor Industrial Environments at 433 and 868 MHz
- 2013
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Ingår i: Wireless personal communications. - : Springer Science and Business Media LLC. - 0929-6212 .- 1572-834X. ; 73:3, s. 587-593
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Tidskriftsartikel (refereegranskat)abstract
- The Ricean K-factor and antenna diversity properties for indoor industrial environments have been characterized for 433 and 868 MHz. The high amount of metallic structures gives a multipath environment that heavily differs from other environments e.g. indoor office environments. The results show that low correlation between receiving antennas can be achieved for shorter antenna distances than in other environments.
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| 4. |
- Ferrer-Coll, Javier, et al.
(författare)
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Characterisation of highly absorbent and highly reflective radio wave propagation environments in industrial applications
- 2012
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Ingår i: IET COMMUNICATIONS. - : Institution of Engineering and Technology (IET). - 1751-8628 .- 1751-8636. ; 6:15, s. 2404-2412
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Tidskriftsartikel (refereegranskat)abstract
- Experience has shown that Bluetooth, Wireless LAN (WLAN), Digital Enhanced Cordless Telecommunications (DECT) and other Industrial, Scientific and Medical (ISM) frequency band wireless technologies developed for office use, have encountered problems when used in critical industrial applications. The development of more reliable wireless solutions requires extensive knowledge of industrial environments with regards to both electromagnetic interference and wave propagation. This study presents the results of the analysis of two important classes of industrial environments having opposite characteristics, one being highly absorbent and the other being highly reflective, with respect to radio wave propagation. The analysis comprises both multipath and path loss characterisation. The results show that wireless solutions with different fundamental properties must be chosen for each of these environments to ensure high reliability. The conclusions of this work can be used as an important reference for further research in this area, as well as the design of new standards and guidelines for selecting wireless solutions in similar industrial environment classes.
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| 5. |
- Ferrer Coll, Javier, 1983-, et al.
(författare)
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Characterization of Electromagnetic Properties in Iron-Mine Production Tunnels
- 2012
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Ingår i: Electronics Letters. - : Institution of Engineering and Technology. - 0013-5194 .- 1350-911X. ; 48:2, s. 62-63
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Tidskriftsartikel (refereegranskat)abstract
- Modern underground mines require reliable wireless communication for transmitting voice data, operating surveillance cameras, and monitoring mining equipment such as heavy vehicles. The electromagnetic characteristics of mines therefore have to be considered when determining the type of wireless technology for such critical applications. In this reported work, measurements of radio interference levels, path loss, and multipath propagation are performed in the world's now largest iron ore mine, situated in Sweden, to determine a suitable wireless technology for this mine.
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| 6. |
- Ferrer-Coll, Javier, et al.
(författare)
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Detection and Suppression of Impulsive Noise in OFDM Receiver
- 2015
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Ingår i: Wireless personal communications. - : Springer-Verlag New York. - 0929-6212 .- 1572-834X.
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Tidskriftsartikel (refereegranskat)abstract
- In recent years, the use of wireless systems in industrial applications has experienced spectacular growth. Unfortunately, industrial environments often present impulsive noise which degrades the reliability of wireless systems. OFDM is an enhanced technology used in industrial communication to monitor the work and movement of employees using high quality video. However, OFDM is sensitive to high amplitude impulsive noise because the noise energy spreads among all OFDM sub-carriers. This paper proposes a receiver structure consisting of two stages: a detector stage combining Fisher’s Quadratic discriminant and Gaussian Hypothesis techniques, and a suppression stage optimized by setting well defined thresholds. The receiver structure has been tested by simulations and measurements providing an increment in the probability of detection and improving the system performance.
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| 7. |
- Stenumgaard, Peter, et al.
(författare)
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Challenges and conditions for wireless machine-to-machine communications in industrial environments
- 2013
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Ingår i: IEEE Communications Magazine. - : IEEE. - 0163-6804 .- 1558-1896. ; 51:6, s. 187-192
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Tidskriftsartikel (refereegranskat)abstract
- Wireless solutions are rapidly growing in machine-to-machine communications in industrial environments. These environments provide challenging conditions in terms of radio wave propagation as well as electromagnetic interference. In this article, results from the characterization of radio channel properties are summarized in order to provide some guidelines for the choice of wireless solutions in industrial environments. In conclusion, it is essential to know the sensitivity of industrial processes to time delay in data transfer. Furthermore, it is important to be aware of the radio interference environment and the manner in which different wireless technologies react upon interference. These steps will minimize the risk of unforeseen expensive disturbances in industrial processes.
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| 8. |
- Berg, H., et al.
(författare)
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Automatic design of pulse coupled neurons for image segmentation
- 2008
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Ingår i: Neurocomputing. - : Elsevier BV. - 0925-2312 .- 1872-8286. ; 71:10-12, s. 1980-1993
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Tidskriftsartikel (refereegranskat)abstract
- Automatic Design of Algorithms through Evolution (ADATE) is a program synthesis system that creates recursive programs in a functional language with automatic invention of recursive help functions and self-adaptive optimization of numerical values. We implement a neuron in a pulse coupled neural network (PCNN) as a recursive function in the ADATE language and then use ADATE to automatically evolve better PCNN neurons for image segmentation. Our technique is generally applicable for automatic improvement of most image processing algorithms and neural computing methods. It may be used either to generally improve a given implementation or to tailor that implementation to a specific problem, which with respect to image segmentation for example can be road following for autonomous vehicles or infrared image segmentation for heat seeking missiles that are to distinguish the heat source of the target from flares.
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| 9. |
- Chilo, José, 1960-, et al.
(författare)
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A flexible electronic nose for odor discrimination using different methods of classification
- 2009
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Ingår i: 2009 16th IEEE-NPSS Real Time Conference - Conference Record. - New York : IEEE. - 9781424444557 ; , s. 317-320, s. 317-320
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Konferensbidrag (refereegranskat)abstract
- Ovarian cancer is one of the leading causes of death from cancer in women. The lifetime risk is around 1.5%, which makes it the second most common gynecologic malignancy (the first one being breast cancer). To have a definitive diagnose, a surgical procedure is generally required and suspicious areas (samples) will be removed and sent for microscopic and other analysis. This paper describes the result of a pilot study in which an electronic nose is used to "smell" the aforementioned samples, analyze the multi-sensor signals and have a close to real-time answer on the detection of cancer. Besides being fast, the detection method is inexpensive and simple. Experimental analysis using real ovarian carcinoma samples shows that the use of proper algorithms for analysis of the multi-sensor data from the electronic nose yielded surprisingly good results with more than 77% classification rate. The electronic nose used in this pilot study was originally developed to be used as a "bomb dog" and can distinguish between e.g. TNT, Dynamex, Prillit. However, it was constructed to be a flexible multi-sensor device and the individual (16) sensors can easily be replaced/exchanged. This is suggestive for further investigations to obtain even better results with new, specific sensors. In another pilot experiment, headspace of an ovarian carcinoma sample and a control sample were analyzed using gas chromatography-mass spectrometry. Significant differences in chemical composition and compound levels were recorded, which would explain the different response obtained with the electronic nose.
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| 10. |
- Chilo, José, et al.
(författare)
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A low cost digital data acquisition system for infrasonic records
- 2007
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Ingår i: IDAACS 2007. - Piscataway, NJ : IEEE. - 9781424413478 ; , s. 35-37, s. 35-37
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Konferensbidrag (refereegranskat)abstract
- This paper describes a new digital data acquisition system that can be used to record signals from infrasound events. The system includes a QF4A512 programmable signal converter from Quickfilter Technologies and a MSP430 microcontroller from Texas Instruments. The signal output of the infrasound sensors is converted to digital via a 16-bits Analog to Digital Converter (ADC). To prevent errors in the conversion process, Anti-Aliasing Filters are employed prior to the ADC Digital filtering is performed after the ADC using a Digital Signal Processor, which is implemented on the QF4A512.
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