Longitudinal vibration of piano strings greatly contributes to the distinctive character low notes. In this paper a simplified modal model is developed, which describes generation phantom partials and longitudinal free modes jointly. The based on simplification that coupling from transverse polarization unidirectional. formulation makes it possible predict prominent components as function frequencies. This provides qualitative insight into vibration, while still capable explaining empirical...

The most commonly used technique in time-frequency analysis is the short-time Fourier transform. It can be to determine spectral components as they change over time by computing transform of a windowed segment signal. A fundamental constraint this method that frequency resolution representation domain will linear design. adaptive nonstationary discrete Gabor offers an alternative does not have limitation. Luenberger observer capable implementation transform, and its numerical advantages are...

This paper presents a new nonlinear least-squares algorithm for fitting band-limited periodic signals with unknown frequency and harmonic content. The solution features model-based recursive calculation method that requires less memory space has smaller computational demand than the known matrix-based algorithms.

Abstract The effect of irradiance during low temperature hardening was studied in a winter wheat variety. Ten-day-old plants were cold-hardened at 5 °C for 11 days under light (250 μmol m -2 s -1 ) or dark (20 conditions. effectiveness significantly lower the dark, spite slight decrease F v /F chlorophyll fluorescence induction parameter, indicating occurrence photoinhibition period light. Hardening caused downshift far-red induced AG (afterglow) thermoluminescence band. faster re-reduction...

The significance of measurement data transfer over unreliable channel has emerged in the last decade, due to spread sensor networks and idea Internet things. This paper investigates behavior fast Fourier transform (FFT)-based power spectral density (PSD) estimation case loss. There are different methods available estimate PSD, but hegemony FFT is beyond dispute, especially real-time applications. PSD estimator loss models, then offers some simple solutions on how can be handled estimation,...

Adaptive Fourier analyzers have been developed for measuring periodic signals with unknown or changing fundamental frequency. Typical applications are vibration measurements and active noise control related to rotating machinery calibration equipment that can avoid the changes of line frequency by adaptation. Higher limitations since computational complexity these relatively high as number harmonic components be measured (or suppressed) is usually above 50. In this paper, based on concept...

Recently, an observer-based algorithm was reviewed that is able to perform recursive sliding discrete Fourier transform (SDFT) [1]. DFT the basic used for analysis [2], but it provides unbiased estimates only if sampling coherent, i.e., ratio of frequency f <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">s</sub> and input signal xmlns:xlink="http://www.w3.org/1999/xlink">in</sub> a rational number. Coherent real-life periodic signals (e.g.,...

The significance of measurement data transfer over unreliable channel has emerged in the last decade, due to spread sensor networks and idea Internet things. paper investigates behavior Fast Fourier Transform (FFT) based power spectral density (PSD) estimation case loss. There are different methods available estimate PSD, but hegemony FFT is beyond dispute, especially real-time applications. PSD estimator loss models, then offers some simple solutions how can be handled estimation, when only...

In distributed signal processing systems, every node samples analog signals by its own AD converter. Sampling is controlled autonomous clocks, that are generally not synchronizable. order to ensure synchronized operation among the different nodes of system, both drift these and jitter sampling handled. This problem investigated in this paper, methods proposed guarantee reduce effect jitter. The solution based on low-level interpolation resampling sampled signals. A realization method...

This paper investigates the behavior of spectral resonator-based observer (RBO) for lossy measurements. The RBO is an efficient real-time method designed measuring harmonic components periodic signals. Recently, some experiments have shown that can tolerate data loss, but no exact criteria convergence been available. main contribution this a set conditions which enable to predict whether able find or not. necessary condition helps recognize situations when error-free estimation not possible....

2020 presented unprecedented challenges in the higher education system. The first wave and still-lasting COVID-19 pandemic brought need for a new mindset, both from educators-teachers students around world. In this paper, we focus on our country Hungary present general feedback distance at Budapest University of Technology, Faculty Electrical Engineering, Informatics viewpoint teachers. After survey within course coordinators faculty, results lessons learned obtained data. form questions...

This paper introduces a "proof of concept" system for Active Noise Control (ANC) where the audio data from reference microphones are travelling through already existing Ethernet network. The realizes active noise control with help multi channel DSP card. algorithm is Filtered Error Least Mean Square (ELMS) - an LMS variant -, which has proven its efficiency previously in different environments. microphone to card digitalised ADSP-BF537 Ez-Lite Kit, and transmitted over counterpart Kit card,...

A nonparametric identification method for linear systems is proposed. The done via synchronized multisine measurements where the synchronization ensured by a resonator-based generator-observer pair. advantage of proposed structure that it works as filter bank and, hence, provides measurement results online. Exponential averaging an option and requires no extra calculations. further can be over any frequency set without loss performance. Explicit formulas are given noise suppression settling...

A new acoustic localization scheme is proposed, which can be applied in sensor networks with low communication bandwidth. The first step of the two-stage algorithm distributed and evaluated at sensors having possibly capabilities. detect various events signal transmit only event descriptors to base station where fusion calculated second using a novel generalized consistency function. Test results validate performance proposed system noisy reverberant environment. According experiments,...

Abstract The GOCE satellite observes gravity gradients with unprecedented accuracy and resolution. observations are reliable within a well-defined measurement bandwidth. In this study, different finite infinite impulse response filters have been designed to obtain the demanded pass. Exhaustive time frequency domain investigations prove that proposed filter can be real competitor of existing solution filtering problem. Keywords: gradiometryGOCEMBWband-pass

Due to the several attractive features of wireless devices they are more and expansively used, but deployment sensors in control applications is not spread yet because unreliable data transfer. This paper introduces a testbed which serves as platform for investigations closed loop adaptive signal processing systems. The novelty this that it makes possible practical tests algorithms environment. Since traditional prepared peculiar problems emerge transfer (e.g. loss), exhaustive study their...

In the recent years, digital waveguide modeling of musical instruments has proven to be an effective tool for sound synthesis purposes, but some practical questions still have remained unanswered. this paper a new equivalent structure string is presented. This can used highly efficient beating and two-stage decay, important characteristic piano sound. The complexity traditional reduced by replacing one models with resonator bank.

A new acoustic localization scheme is proposed, which can be applied in sensor networks with low communication bandwidth. The first step of the two-stage algorithm distributed and evaluated at sensors having possibly capabilities. detect various events signal transmit only event descriptors to base station where fusion calculated second using a novel generalized consistency function. Test results validate performance proposed system noisy reverberant environment. According experiments,...

Our paper introduces a closed-loop wireless control application based on Berkeley MICAz motes and an Analog Devices AD21061 EZ-KIT LITE board. The system realizes active noise (ANC) for the suppression of periodic acoustic disturbances. highlights role synchronous sampling in ANC applications solutions detail. A PLL-like mechanism takes care synchronization, while linear interpolation fits measurement data processing signal processor. controller is resonator-based one which has proven its...

&lt;p&gt;Recently measurement data loss has been of greater interest, due to the spread sensor networks and idea Internet things. A procedure is proposed that able identify most frequently employed models. It assumed communication protocol provides information about loss, i.e. so-called availability indicator function known. The power spectral density (PSD) representative for model, can be used identification. Spectral estimation carried out by Fast Fourier Transform (FFT) based techniques....

Office employees are exposed to acoustic noise, especially in an open office environment. Passive or active headsets sufficiently reduce the level of but their long-time wear is uncomfortable. The paper presents headrest system built into a chair. Feedforward control utilized with multiple reference microphones, and flexible gooseneck microphones serve as error sensors. sensors surround chair, allowing suppression sound waves arriving from any direction. concept has been tested by extensive...

The paper presented a DSP-based electromagnetic flowmeter. There are 4 pairs of electrodes and pressure sensor for effective flowrate measurement in partially filled pipes. Although this setup is able to measure different flow profiles, our development focused on the improvement accuracy by signal processing methods. A sinusoidal excitation used allowing fast sampling flowrate. coils driven class-D amplifiers minimizing power consumption module. demodulation electrode voltage carried out...

Spectral observer is appropriate for investigating the frequency domain properties of signals. Since spectral analysis a very common method, this can be used widely in many applications. The paper introduces novel resonator based and control algorithm that require reduced amount data operation, so they are utilization signal processing systems with limited resources (e.g. wireless sensor networks). reduction achieved by deployment sign error principle. For improvement transient structures...