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Height estimation of scatterers in complex environments via the Tomographic Synthetic Aperture Radar (TomoSAR) technique is still a valuable research field. The parametric spectral estimation approach constitutes a powerful tool to identify the superimposed scatterers with different complex reflectivities, located at different heights in the same range–azimuth resolution cell. Unfortunately, this approach requires prior knowledge about the number of scatterers for each pixel, which is not possible in practical situations. In this paper, we propose a method that analyzes the scree plot, generated from the spectral decomposition of the multidimensional covariance matrix, in order to estimate automatically the number of scatterers for each resolution cell. In this context, a properly improved regularization step is included during the reconstruction process, transforming the parametric MUSIC estimator into a non-parametric method. The experimental results on two data sets covering high elevation towers, with different facade coating characteristics, acquired by the TerraSAR-X satellite highlighted the effectiveness of the proposed regularized MUSIC for the reconstruction of high man-made structures compared with classical approaches. [ABSTRACT FROM AUTHOR]

• A tailor-made cylindrical concrete implantable module (CCIM) was proposed for damage perception in plate-like concrete structures. • The CCIM can be directly implanted into inspected structure to transmit and receive probing stress waves using pulse-echo manner, which allows conveniently removing and updating the CCIM when the devices failed to work. • A CCIM-based multiple signal classification (MUSIC) algorithm is proposed to realize two-dimensional damage visualization in a fusion strategy manner. In this research, a tailor-made cylindrical concrete implantable module (CCIM) was proposed for damage imaging in concrete structures. The CCIM can be directly implanted into inspected structure to transmit and receive probing stress waves, which allows conveniently removing and updating CCIM when devices failed to work. Moreover, a CCIM-based multiple signal classification (MUSIC) algorithm is proposed to realize two-dimensional damage visualization. Based on meso-level finite element simulation, considering concrete as a three-phase composite material, the stress wave propagation characteristics can be revealed and the effectiveness of CCIM-based MUSIC imaging method has been investigated. To verify the proposed method experimentally, a pair of CCIMs were fabricated and implanted into two concrete specimens with different configurations. The results could effectively pinpoint damage location within inspected area. The proposed hardware and algorithm has great potential to overcome the disadvantage of short service period and could be applied for damaging imaging in concrete structures. [ABSTRACT FROM AUTHOR]

Height estimation of scatterers in complex environments via the Tomographic Synthetic Aperture Radar (TomoSAR) technique is still a valuable research field. The parametric spectral estimation approach constitutes a powerful tool to identify the superimposed scatterers with different complex reflectivities, located at different heights in the same range–azimuth resolution cell. Unfortunately, this approach requires prior knowledge about the number of scatterers for each pixel, which is not possible in practical situations. In this paper, we propose a method that analyzes the scree plot, generated from the spectral decomposition of the multidimensional covariance matrix, in order to estimate automatically the number of scatterers for each resolution cell. In this context, a properly improved regularization step is included during the reconstruction process, transforming the parametric MUSIC estimator into a non-parametric method. The experimental results on two data sets covering high elevation towers, with different facade coating characteristics, acquired by the TerraSAR-X satellite highlighted the effectiveness of the proposed regularized MUSIC for the reconstruction of high man-made structures compared with classical approaches.

This article provides a cross-sectional overview of the evolution of music teaching methods over a 160-year timeline. The objective of the study is limited to examining the mainstream trends in the development of methods, or their manifestations, as well as discussing the causes behind them. The objective is also to investigate the methodical state of the 21st century teaching. The data consists of previous studies, music textbooks and learning diaries of class teacher students (N=79). The analysis of the data is based on analytic-historical and data-driven content analysis. The time period from 1860 to1970 has focused on developing the methods. The participatory and functional methods have remained dominant for the longest time. As we enter the 1980s, methods are gradually being phased out and they are used only occasionally, or the main focus is not on them anymore. As a result, teaching methods are fragmented and their implementations depend on the teacher's pedagogical skills in music teaching. [ABSTRACT FROM AUTHOR]

Copyright of Telecommunication Engineering is the property of Telecommunication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to improve resolution and direction of arrival (DOA) estimation of two closely spaced sources, in context of array processing, a new algorithm is presented. However, the proposed algorithm combines both spatial sampling technic to widen the resolution and a high resolution method which is the Multiple Signal Classification (MUSIC) to estimate the DOA of two closely spaced sources impinging on the far-field of Uniform Linear Array (ULA). Simulations examples are discussed to demonstrate the performance and the effectiveness of the proposed approach (referred as Spatial sampling MUSIC SS-MUSIC) compared to the classical MUSIC method when it's used alone in this context. [ABSTRACT FROM AUTHOR]

Za sprovođenje savremenih operacija, kako na operativno-strategijskom, tako i na taktič kom nivou, izuzetno je važno da se obezbedi kontinuirani nadzor vazdušnog prostora. Poznato je da su aktivni radarski sistemi, na kojima se kod nas trenutno zasniva nadzor vazdušnog prostora, u ratnim uslovima veoma ranjivi i podložni elektronskim i borbenim dejstvima protivnika, što je u toku rata 1999. godine i praktično potvrđeno. Kao alternativa aktivnim radarskim sistemima nameće se koncept pasivnog nadzora vazdušnog prostora korišćenjem distribuiranih multisenzorskih sistema. Predmet širih istraživanja predstavljaju tehnička rešenja integrisanog multisenzorskog sistema za pasivan nadzor vazdušnog prostora, koji se sastoji od sledećih podsistema za nadzor vazdušnog prostora: na radio-gonimetarskom principu u frekvencijskom opsegu 20-3000 MHz, na zvukometrijskom principu, na principu vizuelnih osmatračkih stanica, na termovizijskom i televizijskom principu. U ovom radu analizirani su opšti principi pasivnog nadzora vazdušnog prostora multisenzorskim sistemima i predložena je tehnička koncepcija radio-goniometarskog i zvukometrijskog podsistema. / It is very important to provide continuous air surveillance in to realize modern operations on the operational-strategic level and tactical, as well. It is well known that active radar systems, on which air surveillance is based in our country, are very vulnerable in war times and susceptible to the electronic counter and combat attacks of the enemy, what is shown practically in 1999 war. Air surveillance by passive multi-sensor systems is a possible alternative to the air surveillance by the active radar systems. Subjects of our wider research are technical solutions of integrated multi-sensor systems for passive air surveillance which consists of the following subsystems: a subsystem for the air communication intelligence within the frequency range 20-3000 MHz based on intercept/direction finding principle, a subsystem for the air surveillance based on the acoustic intelligence, a subsystem for the air surveillance based on the station for the visual intelligence, a subsystem for air surveillance based on thermo-vision and television principle. General principles of air surveillance are presented, and the concepts of the subsystems for the air communication intelligence and acoustic intelligence are proposed in this paper.

U ovom radu je, polazeći od opštih principa izviđanja radio-komunikacija analiziran problem izviđanja radio-komunikacija u VF opsegu 1,6-30 MHz na operativno-strategijskom nivou koje se sprovodi u funkciji obaveštajnog obezbeđenja. Izložen je koncept širokopojasnog multifunkcionalnog radio-goniometra u kojem su integrisane funkcije automatskog presretanja i goniometrisanja signala, koji treba da omogući trenutni i potpuni nadzor (otkrivanje i goniometrisanje) svih aktivnih emisija u kompletnom VF frekvencijskom opsegu koje nisu kraće od 10 ms. Ovaj goniometar predstavlja osnovicu budućeg automatizovanog radioizviđačkog sistema za VF opseg, koji sistemu komandovanja savremenim operacijama treba da omogući potpuni uvid u stanje, odnosno praćenje aktivnosti radio-komunikacija u kompletnom VF opsegu, što postojeći sistem za izviđanje VF frekvencijskog opsega ne obezbeđuje. Izložena problematika zasniva se na analizi iskustava i trendova u ovoj oblasti u svetu, na iskustvima stečenim u VTI kroz dosadašnje istraživačke i razvojne zadatke, posebno kroz razvoj i terenska ispitivanja radio-goniometra za VVF/UVF opseg. / Starting from the elaboration of the basic principles of communication intelligence, a problem of communication intelligence in HF range 1,6-30 MHz on the operational-strategic level is analyzed in detail. A concept of the wide-band multifunctional direction finder with integrated intercept and direction finding functions is presented. The direction finder should provide complete surveillance of the HF range and interception with direction finding of all active signals in given frequency range which are not shorter than 10 ms. The direction finder is the key element of the future automated radio reconnaissance system for the HF range, that should provide a complete insight of the signal activities in the HF range, which the existing communication intelligence system does not provide. The subject matter of this paper is based on the analysis of experiences and current trends in this field in the world, on experiences gained in VTI in previous research and development projects, especially in development and testing of the prototype of the direction finder fot the VHF/UHF frequency range.

The goal of the paper is to use the MUSIC method to estimate the fundamental frequency of signals, and compare the results with the ones obtained by the DFT method. Real speech signals are considered in the paper. Lithuanian vowel sound fundamental frequency is estimated by the MUSIC and DFT methods.

Mathematics is applied in all forms of human activity and therefore also in physical education teaching. According to the curriculum plan, 2nd grade students are expected to be able to differentiate a rectangle from a square, open from closed broken lines, straight from curved lines and also calculate their lengths. The aim of this paper is to show a correlation between physical education and mathematics so that students can learn the above mentioned mathematical terms through physical activity and in a fun and interesting way (dancing, exercises, and singing). The research took place in the elementary school "Rada Miljkovic " in Jagodina. Thirty 2nd grade students were examined and a questionnaire with 10 questions was used as an instrument. The organizational form of teaching was cellular. The acquired results showed a high level of positive effect of physical science on mastering mathematical problems. [ABSTRACT FROM AUTHOR]

Abstract: Rheumatoid arthritis (RA) is a multi-systemic autoimmune disease that leads to substantial morbidity and mortality. In this paper, as spectral analysis methods of Multiple Signal Classification (MUSIC) method is used in order to extract the significant features from the right and left hand Ulnar artery Doppler signals for the diagnosis of RA disease. The MUSIC method has been used as subspace method. To extract features from Doppler signals obtained from the right and left hand Ulnar arterial the MUSIC method model degrees of 5, 10, 15, 20, and 25 were used. Then, an adaptive network based fuzzy inference system (ANFIS) was applied to features extracted from the right and left hand Ulnar artery Doppler signals for classifying RA disease. The methods are not new, but the study has a novelty in that the application area of these methods is new. In the hybrid model, the combination of MUSIC and ANFIS yielded classification accuracies of 95% (for a model degree of 20) using the right hand Ulnar artery and classification accuracies of 91.25% (for a model degree of 10) using left hand Ulnar artery Doppler signals in the diagnosis of RA disease. The proposed approach has potential to help with the early diagnosis of RA disease for the specialists who study this subject. [ABSTRACT FROM AUTHOR]

Copyright of Nassarre is the property of Institucion Fernando el Catolico and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A beamforming technique is introduced to measure the normal acoustic impedance at both normal and oblique incidence in a free field. In the proposed method, microphone array signals are decomposed into incident and reflected waves using an adaptive nulling algorithm, which is a type of beamforming algorithm. The acoustic impedance can then be calculated from the ratio of these two signals. To obtain better results, the pressure vector commonly used in array signal processing is replaced with the transfer function vector between each microphone, and the white Gaussian noise is suppressed by a wavelet shrinkage technique. For an accurate experimental setup, the incident and reflected angles are estimated by the multiple signal classification method with spatial smoothing. The experiments conducted in a semi-anechoic room show that the proposed method is efficient and accurate in measuring the normal acoustic impedance of sound-absorbing materials under a free field condition. [ABSTRACT FROM AUTHOR]

To date, for the tomographic signals obtained in cross-borehole radar measurement in which transmitting and receiving antennas are scanned independently, a position estimation method for the isolated reflector has been studied by applying the transmission and reception array MUSIC method. However, when the operating wavelength and the size of the conducting cylinder cannot be neglected, as in the case of buried pipes, there is an error in the estimated position in the conventional method when the scattered wave from the point scatterer is used as the steering vector for position estimation. In this paper, the steering vector obtained from rigorous solution of scattering from a conducting cylinder is used. It is shown that the position estimation accuracy is improved by taking into account the effect of the elimination of the direct wave. It is also shown that the cylinder position and the radius can be estimated simultaneously by using the cylindrical radius as an estimation parameter. The effectiveness of multifrequency synthesis is discussed. © 2006 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 89(8): 26–36, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.20271 [ABSTRACT FROM AUTHOR]

Abstract: Sinusoidal frequency estimation has been studied for many years. The MUSIC method represents a class of super-resolution methods based on subspace decomposition. However, the MUSIC method has poor performance in impulsive noise environments due to the prevalence of outliers and very large noise variance. A more robust method called trimmed correlation based-MUSIC (TR-MUSIC) method is proposed in this paper. Through a trimming operation, outliers in the samples participating in the correlation calculation are discarded, yielding a correlation sequence that is closer to the true underlying correlation. The amount of trimming is determined by the Mahalanobis distance in which robust estimates of location and scale are utilized to compensate for outlier effects. Frequency estimation results from the eigendecomposition of the trimmed correlation matrix. In the simulations, we take -stable noise () as an example of impulsive noise. The proposed method is very robust and performs better than the conventional MUSIC and other robust methods. Furthermore, it can be applied to real signals as well as complex signals. [Copyright &y& Elsevier]

In order to study the cause of unwanted electromagnetic emissions under the actual operating conditions of electronic and industrial devices, it is necessary to measure the spatial distribution of the unwanted electromagnetic waves outside the devices and to identify the positions of the sources of unwanted electromagnetic waves inside the devices. The authors attempted to estimate the sources of the electromagnetic near-fields of the devices at low frequencies (less than several tens of megahertz) by placing several electromagnetic field sensors around the devices to observe the spatial distributions of the unwanted emissions. In this paper, the MUSIC method is applied to the observed vector component waveforms of the magnetic fields radiated from low-frequency current loops (magnetic dipole sources) to estimate the three-dimensional location and orientation of the sources. The effectiveness of the method and its error are evaluated by numerical simulations and experiments. © 2005 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 88(6): 1–10, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.20198 [ABSTRACT FROM AUTHOR]

Estimation of the transmission point in the ionosphere for ELF/VLF waves arriving at the ground after propagation in the magnetosphere is performed by MUSIC, an estimation method having high resolution. This paper not only constructs an estimation method based on the observation data model common to various direction-finding methods, but also proposes a method of estimating the direction and polarization of the direct wave by using a model that expresses the propagation effects between the ground and the ionosphere in terms of superposition of multiply reflected waves. In the simulation assuming observation of three electromagnetic field components on the ground, the results of estimation by both methods are compared. It is confirmed that the estimated values are superior to those obtained by the conventional methods if more than 10 reflections are taken into account for estimation of a transmission point that is far away with a large angle of incidence at the observation point. Even when the wave is transmitted through the spread-out region in the lower ionosphere, the direction of the center of the transmission region can be estimated by MUSIC taking account of multiply reflected waves. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 85(9): 21–30, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.1122 [ABSTRACT FROM AUTHOR]