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Wyniki wyszukiwania dla: digital signage
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Parametric impulsive noise detector for corrupted audio signals based on hidden Markow model
PublikacjaThe paper addresses the problem of impulsive noise detection for audio signals. A structure of threshold parameter detectors using modelingof signals was introduced. the algorithm of the noise detection, based on discrete-time hidden Markow model (HMM)of whitened audio signal is elaborated
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Higuchi fractal dimension analysis of surface EMG signals and determination of active electrode positions
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Evaluation of Barkhausen Noise and Magnetoacoustic Emission Signals Properties for Plastically Deformed Armco Iron
PublikacjaArtykuł prezentuje wyniki badania wpływu różnych rodzajów deformacji plastycznej na właściwości magnetoakustyczne żelaza Armco. Badane były dwie serie próbek - pierwsza składała się ze wstępnie wyżarzonych próbek, które następnie były walcowane na zimno, w skład drugiej wchodziły natomiast próbki wycięte z komercyjnie dostępnej blachy wykonanej z żelaza Armco a następnie poddane obciążeniom rozciągającym. Walcowanie na zimno prowadzi...
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Detection and Direction-of-Arrival Estimation of Weak Spread Spectrum Signals Received with Antenna Array
PublikacjaThis paper presents a method for the joint detection and direction of arrival (DOA) estimation of low probability of detection (LPD) signals. The proposed approach is based on using the antenna array to receive spread-spectrum signals hidden below the noise floor. Array processing exploits the spatial correlation between phase-delayed copies of the signal and allows us to evaluate the parameter used to make the decision about the...
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Signals Features Extraction in Radioisotope Liquid-Gas Flow Measurements using Autocorrelation Function
PublikacjaKnowledge of the two-phase flow structure is essential for the proper conduct of industrial processes. Description of liquid-gas flow regimes is possible by using of data analysis in time, frequency, or state-space domain. In this research studies, the autocorrelation function is applied for analysis of signals obtained for liquid-gas flow by use gamma-ray absorption. The experiments were carried out on the laboratory hydraulic...
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Signals features extraction in radioisotope liquid-gas flow measurements using wavelet analysis
PublikacjaKnowledge of the structure of a flow is significant for the proper conduct of a number of industrial processes. In this case, a description of a two-phase flow regimes is possible by use of the time-series analysis in time, frequency and state-space domain. In this article the Discrete Wavelet Transform (DWT) is applied for analysis of signals obtained for water-air flow using gamma ray absorption. The presented method was illustrated...
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Sparse vector autoregressive modeling of audio signals and its application to the elimination of impulsive disturbances
PublikacjaArchive audio files are often corrupted by impulsive disturbances, such as clicks, pops and record scratches. This paper presents a new method for elimination of impulsive disturbances from stereo audio signals. The proposed approach is based on a sparse vector autoregressive signal model, made up of two components: one taking care of short-term signal correlations, and the other one taking care of long-term correlations. The method...
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Subjective Quality Evaluation of Speech Signals Transmitted via BPL-PLC Wired System
PublikacjaThe broadband over power line – power line communication (BPL-PLC) cable is resistant to electricity stoppage and partial damage of phase conductors. It maintains continuity of transmission in case of an emergency. These features make it an ideal solution for delivering data, e.g. in an underground mine environment, especially clear and easily understandable voice messages. This paper describes a subjective quality evaluation of...
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Избранные проблемы контрастивного анализа цифровых акустических изображений лексем разных языков [Selected problems in the analysis of digital acoustic images for lexemes from various languages]
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Избранные проблемы контрастивного анализа цифровых акустических изображений лексем разных языков [Selected problems in the analysis of digital acoustic images for lexemes from various languages]
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Monitoring the fracture process of concrete during splitting using integrated ultrasonic coda wave interferometry, digital image correlation and X-ray micro-computed tomography
PublikacjaThe paper deals with the continuous-time monitoring of mechanical degradation in concrete cubes under splitting. A series of experiments performed with integrated coda wave interferometry (CWI) and digital image correlation (DIC), supported with X-ray micro-computed tomography (micro-CT) is reported. DIC and micro-CT techniques were used to characterize the fracture process in detail. CWI method was proved to be effective in the...
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El empleo en el marco de la transformación digital: Gig Economy vs Open Collaboration ¿dos caras de una misma moneda?
PublikacjaTal y como plantea Pérez [43, 44], estamos viviendo los efectos de una revolución tecnológica ligada al desarrollo de las TICs. Los procesos de innovación, describe, se retroalimentan colectivamente, involucrando diferentes actores (productores, proveedores, distribuidores y consumidores) entrelazados en clústeres o redes dinámicas y complejas. Estos procesos colectivos ayudan a desarrollar e implementar tecnologías y magnifican...
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Development of the sound field 3D intensity probe based on miniature microphones
PublikacjaThe engineered measuring probe uses three pairs of miniature microphones coupled. The signals from the microphones after an initial amplification are fed to differential circuits. Due to the required symmetry of the circuit it was necessary to select electronic components very carefully. Moreover, additional digital signal processing techniques were applied to avoid amplitude and phase mismatch. The view of the engineered probe...
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Impact of Microphytobenthos Photosynthesis on the Characteristics of the Echo Signal from Baltic Sandy Sediments
PublikacjaThe understanding the influence of biological processes on the characteristics of the signals backscattered by the sea floor is crucial in the development of the hydroacoustical benthic habitat classification techniques. The impact of the microphytobenthos photosynthesis on the acoustical backscattering properties of the Atlantic sandy sediments was previously demonstrated by Holliday et al. (2004) and Wildman and Huettel (2012). To...
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Supply current signal and artificial neural networks in the induction motor bearings diagnostics
PublikacjaThis paper contains research results of the diagnostics of induction motor bearings based on measurement of the supply current with usage of artificial neural networks. Bearing failure amount is greater than 40% of all engine failures, which makes their damage-free operation crucial. Tests were performed on motors with intentionally made bearings defects. Chapter 2 introduces the concept of artificial neural networks. It presents...
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Classifying type of vehicles on the basis of data extracted from audio signal characteristics
PublikacjaThe aim of this study is to find and optimize a feature vector for an automatic recognition of the type of vehicles, extracted form an audio signal. First, the influence of weather-based conditions of road surface on spectral characteristic of the audio signal recorded from a passing vehicle in close proximity to the road is discussed. Next, parameterization of the recorded audio signal is performed. For that purpose, the MIRtoolbox,...
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A concept of Signal Equalization Method Based on Music Genre and the Listener's Room Characteristics
PublikacjaA research study that investigates the influence of the room acoustics environment on the frequency characteristic of the audio signal playback is presented. First, a novel spectral equalization method of the room acoustic conditions is introduced. On the basis of the frequency response of the room, a system for room acoustics compensation based on eight-band equalizer is proposed. The system settings depend on music genre. In...
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Dynamic Signal Strength Mapping and Analysis by Means of Mobile Geographic Information System
PublikacjaBluetooth beacons are becoming increasingly popular for various applications such as marketing or indoor navigation. However, designing a proper beacon installation requires knowledge of the possible sources of interference in the target environment. While theoretically beacon signal strength should decay linearly with log distance, on-site measurements usually reveal that noise from objects such as Wi-Fi networks operating in...
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Methods of measurement signal acquisition from the rotational flow meter for frequency analysis
PublikacjaOne of the simplest and commonly used instruments for measuring the flow of homogeneous substances is the rotational flow meter. The main part of such a device is a rotor (vane or screw) rotating at a speed which is the function of the fluid or gas flow rate. A pulse signal with a frequency proportional to the speed of the rotor is obtained at the sensor output. For measurements in dynamic conditions, a variable interval between...
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Signal Partitioning Algorithm for Highly Efficient Gaussian Mixture Modeling in Mass Spectrometry
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Modeling of a rock fall using the discrete element method and study of the seismic signal
PublikacjaW artykule przedstawiono opis fal sejsmicznych, zastosowanie dyskretnej metody elementów do opisu obrywu skalnego, opis programów obliczeniowych oraz obliczenia numeryczne wg. podanych programów obliczeniowych.
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Pitch estimation of narrowband-filtered speech signal using instantaneous complex frequency
PublikacjaIn this paper we propose a novel method of pitch estimation, based on instantaneous complex frequency (ICF). New iterative algorithm for analysis of ICF of speech signal in presented. Obtained results are compared with commonly used methods to prove its accuracy and connection between ICF and pitch, particularly for narrowband-filtered speech signal.
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Improving signal quality of a speech codec using hybrid perceptual-parametric algorithm
PublikacjaW artykule zaprezentowano hybrydową architekturę parametryczno-perceptualną kodeka mowy. Jego podstawę stanowi kodek CELP, który wspomagany jest kodekiem perceptualnym. Celem zastosowania proponowanej metody jest uzyskanie poprawy jakości kodowania sygnału mowy. Badaniom poddano dwie architektury, z których w jednej dźwięczne części sygnału rezydualnego kodeka CELP kodowane są perceptualnie. Drugi z proponowanych kodeków dokonuje...
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Modeling of a rock fall using the discrete element method and study of the seismic signal
PublikacjaMechanizm dużego spadającego bloku skalnego lub lawiny pozostaje nadal słabo rozpoznany zarówno w zakresie pęknięć jak i procesów propagacji. Jedynie ilościowe dane, które aktualnie są mierzone i uchwytne podczas spadania skały, zarejestrowane są jako sejsmiczne sygnały przez szereg sejsmografów. Właściwości sygnału (amplituda, trwanie, częstotliwość) są wyraźnie powiązane z cechami spadania (masa, wysokość spadania, odległość...
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AM Modulation Signal Estimation Allowing Further Research on Sources of Voltage Fluctuations
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Influence of accelerometer signal pre-processing and classification method on human activity recognition
PublikacjaA study of data pre-processing influence on accelerometer-based human activity recognition algorithms is presented. The frequency band used to filter-out the accelerometer signals and the number of accelerometers involved were considered in terms of their influence on the recognition accuracy. In the test four methods of classification were used: support vector machine, decision trees, neural network, k-nearest neighbor.
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Application of TMS320c67xx signal processors for SONIC-self-optimizing narrowband interference canceler
PublikacjaThe paper presents a laboratory system for testing active control algorithms of acoustics noise in ducts. An applied algorithm - self-optimizing narrowband interference canceller (SONIC), allows one to remove narrowband disturbances of constant or slowly time-varying frequencies. Example experimental results of using the laboratory system for supression of sinusoidal disturbance are described. An electronic part of the system was...
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Pitch estimation of narrowband-filtered speech signal using instantaneous complex frequency
PublikacjaIn this paper we propose a novel method of pitch estimation, based on instantaneous complex frequency (ICF). New iterative algorithm for analysis of ICF of speech signal in presented. Obtained results are compared with commonly used methods to prove its accuracy and connection between ICF and pitch, particularly for narrowband-filtered speech signal.
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Seafloor characterisation using multibeam sonar echo signal processing and image analysis
PublikacjaThe authors propose the approach to multibeam seafloor characterisation which relies on the combined, concurrent use of two different techniques of multibeam sonar data processing. The first one is based on constructing the grey-level sonar images of seabed using the echoes received in the consecutive beams. Then, the parameters describing the local region of sonar image, namely, the local standard deviation of a grey level, and...
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Underwater acoustic communication system using broadband signal with hyperbolically modulated frequency
PublikacjaThe implementation of reliable acoustic underwater communication in shallow waters is a scientific and engineering challenge, mainly due to the permanent occurrence of the multipath phenomenon. The article presents the concept of a transmission system using a broadband signal with hyperbolically modulated frequency (HFM) to transmit data symbols and synchronize data frames. The simulation tests were carried out in channels with...
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Intelligent Audio Signal Processing − Do We Still Need Annotated Datasets?
PublikacjaIn this paper, intelligent audio signal processing examples are shortly described. The focus is, however, on the machine learning approach and datasets needed, especially for deep learning models. Years of intense research produced many important results in this area; however, the goal of fully intelligent signal processing, characterized by its autonomous acting, is not yet achieved. Therefore, a review of state-of-the-art concerning...
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Wastes from Agricultural Silage Film Recycling Line as a Potential Polymer Materials
PublikacjaThe recycling of plastics is currently one of the most significant industrial challenges. Due to the enormous amounts of plastic wastes generated by various industry branches, it is essential to look for potential methods for their utilization. In the presented work, we investigated the recycling potential of wastes originated from the agricultural films recycling line. Their structure and properties were analyzed, and they were...
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Measurements of Two-phase Flows in Pipelines Using Radioisotopes and Statistical Signal Processing
PublikacjaThis paper presents an application of radiotracers and gamma absorption method in two-phase flow measurements in pipelines. Two different methods were implemented to analysis of acquired signals. Investigated methods are based on the cross-correlation function and the phase of the cross-spectral density distribution. The examples presented in the article illustrate the application of the radioisotopes to evaluation of liquid-gas...
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Geospatial Coverage and Signal Quality Measurements of Terrestrial DAB+ Network in Northern Poland
PublikacjaModern signal coverage maps are prepared based on industry-standard radio propagation models, which take into account a number of parameters, including: type of antenna, distance from the transmitter, type of terrain, etc. However, such simulations are prone to location-specific inaccuracies, and should be verified with in-situ measurements. This paper presents results of a field test of a terrestrial DAB+ (Digital Audio Broadcasting...
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Combined method of multibeam sonar signal processing and image analysis for seafloor classification
PublikacjaThe combined approach to seafloor characterisation was investigated. It relies on calculation of several descriptors (parameters) related to seabed type using three types of multibeam sonar data obtained during seafloor sensing: 1) the grey-level sonar images (echograms) of seabed, 2) the 3D model of the seabed surface which consists of bathymetric data, 3) the set of time domain bottom echo envelopes received in the consecutive...
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Butyrylcholinesterase signal sequence self-aggregates and enhances amyloid fibril formation in vitro
PublikacjaAlzheimer’s disease (AD) pathogenesis has been attributed to extracellular aggregates of amyloid β (Aβ) plaques and neurofibrillary tangles in the human brain. It has been reported that butyrylcholinesterase (BChE) also accumulates in the brain Aβ plaques in AD. We have previously found that the BChE substitution in 5′UTR caused an in-frame N-terminal extension of 41 amino acids of the BChE signal peptide. The resultant variant...
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Radar Signal Parameters Estimation Using Phase Accelerogram in the Time-Frequency Domain
PublikacjaRadar signal parameter estimation, in the context of the reconstruction of the received signal in a passive radar utilizing other radars as a source of illumination, is one of the fundamental steps in the signal processing chain in such a device. The task is also a crucial one in electronic reconnaissance systems, e.g. ELINT (Electronic Intelligence) systems. In order to obtain accurate results it is important to measure, estimate...
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Decoding of the FSK signal with noise and distortion with the use of coefficients of the time-frequency transform.
PublikacjaStreszczenie: Przeanalizowano sygnał z modulacją FSK wykorzystując metodę transformacji czasowo-częstotliwościowej różniące się sposobem podziału płaszczyzny TF na atomy: krótko-okresowej transformacji Fouriera, transformacji falkowej i transformacji pakietami falkowymi. Transformacja falkowa zapewnia dobrą lokalizację czasową zakłóceń o wielkiej częstotliwości, podczas gdy transformacja pakietami falkowymi zapewnia dobrą lokalizację...
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Measurements of passive components using of an IEEE 1149.4 mixed-signal test bus
PublikacjaW pracy przedstawiono wyniki badań nad wykorzystaniem magistrali testującej mieszanej sygnałowo IEEE 1149.4 do pomiarów elementów pasywnych zamontowanych na pakietach elektronicznych. Do badań użyto wyposażonych w magistralę układów scalonych typu STA400. Zaprezentowano metody pomiaru rezystancji pojedynczych elementów z wykorzystaniem źródła prądowego oraz źródła VH znajdującego się w analogowych modułach ABM układu STA400. Pokazano...
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Compatible DC and small-signal MOSFET models for radio and microwave frequency simulation
PublikacjaZaprezentowano nowy model stałoprądowy tranzystora MOS i kompatybilny z nim uogólniony nie-quasi-statyczny model małosygnałowy. Model stałoprądowy został eksperymentalnie zweryfikowany dla tranzystorów MOS o długości kanału od 75 nm do kilkunastu mikrometrów, a model małosygnałowy od zera herców do 30 GHz.
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Acoustic Processor of the Mine Countermeasure Sonar
PublikacjaThis paper presents the concept of an acoustic processor of the mine countermeasure sonar. Developed at the Department of Marine Electronics Systems, Gdansk University of Technology, the acoustic processor is an element of the MG-89, an underwater acoustic station. The focus of the article is on the modules of the processor. They are responsible for sampling analogue signals and implementing the algorithms controlling the measurement...
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Enhanced voice user interface employing spatial filtration of signals from acoustic vector sensor
PublikacjaSpatial filtration of sound is introduced to enhance speech recognition accuracy in noisy conditions. An acoustic vector sensor (AVS) is employed. The signals from the AVS probe are processed in order to attenuate the surrounding noise. As a result the signal to noise ratio is increased. An experiment is featured in which speech signals are disturbed by babble noise. The signals before and after spatial filtration are processed...
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Application of wavelet transform in analysis of guided wave propagation signals for damage detection in a steel plate
PublikacjaThe paper presents results of experimental investigations on damage detection using guided wave propagation technique. The tested specimen was a steel plate with a defect in the form of a rectangular notch. Lamb waves were excited by a PZT actuator and sensed by a laser vibrometer. Since reflections from damage in registered signals are often masked by measurement noise, for identification of time of reflections from damage, continuous...
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Generalized adaptive comb filters/smoothers and their application to the identification of quasi-periodically varying systems and signals
PublikacjaThe problem of both causal and noncausal identification of linear stochastic systems with quasiharmonically varying parameters is considered. The quasi-harmonic description allows one to model nonsinusoidal quasi-periodic parameter changes. The proposed identification algorithms are called generalized adaptive comb filters/smoothers because in the special signal case they reduce down to adaptive comb algorithms used to enhance...
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A novel method of local chirp-rate estimation of LFM chirp signals in the time-frequency domain
PublikacjaIn the paper, novel dynamic representations of a complex signal in the time-frequency domain are introduced. The proposed approach is based on using the gradient of the short-time Fourier transform complex phase. A channelized instantaneous complex frequency (CICF) and a complex local group delay (CLGD) are included in the presented signal representations. An application of the newly-introduced distributions is demonstrated by...
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New semi-causal and noncausal techniques for detection of impulsive disturbances in multivariate signals with audio applications
PublikacjaThis paper deals with the problem of localization of impulsive disturbances in nonstationary multivariate signals. Both unidirectional and bidirectional (noncausal) detection schemes are proposed. It is shown that the strengthened pulse detection rule, which combines analysis of one-step-ahead signal prediction errors with critical evaluation of leave-one-out signal interpolation errors, allows one to noticeably improve detection results...
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Real and imaginary motion classification based on rough set analysis of EEG signals for multimedia applications
PublikacjaRough set-based approach to the classification of EEG signals of real and imaginary motion is presented. The pre-processing and signal parametrization procedures are described, the rough set theory is briefly introduced, and several classification scenarios and parameters selection methods are proposed. Classification results are provided and discussed with their potential utilization for multimedia applications controlled by the...
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Symulacja metody korekty składowej stałej w sygnale przetwarzanym przez przetwornik "napięcie-częstotliwość"
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Wykrywanie on-line anomalii w odebranym sygnale PSK za pomocą zespolonej pulsacji chwilowej
PublikacjaJednym z głównych problemów w analizie sygnałów PSK (ang. Phase Shift Keying) jest wykrywanie anomalii występujących w sygnale odebranym. Większość urządzeń stosowanych do analizy sygnałów PSK (np. oscyloskopy cyfrowe, analizatory widma) w celu wykrycia anomalii wykorzystuje algorytm EVM (ang. Error Vector Magnitude) w którym bada się, on-line, różnicę między konstelacją PSK, a skupieniami odebranych symboli zespolonych. W związku...
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A cryptic ribosome binding site, false signals in reporter systems and avoidance of protein translation chaos
PublikacjaThe expression of reporter gene may be induced by activation of cryptic signalling sequences, as we found while constructing the mutS-lacZ fusion gene. We cloned the Escherichia coli lacZ gene encoding beta-galactosidase into a plasmid vector carrying the Thermus thermophilus mutS gene. The clones expected to produce beta-galactosidase as the C-terminal fusion were selected for the complementation of beta-galactosidase activity...