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Search results for: digital image processing
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Computer vision techniques applied for reconstruction of seafloor 3D images from side scan and synthetic aperture sonars data
PublicationThe Side Scan Sonar and Synthetic Aperture Sonar are well known echo signal processing technologies that produce 2D images of the seafloor. Both systems combines a number of acoustic pings to form a high resolution image of seafloor. It was shown in numerous papers that 2D images acquired by such systems can be transformed into 3D models of seafloor surface by algorithmic approach using intensity information, contained in a grayscaled...
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Dual-wavelength polarimeter application in investigations of the optical activity of a langasite crystal
PublicationA method of high accuracy polarimetry, which includes optical activity measurements systematic errors, was realized with dual-wavelength polarimeter for two wavelengths of 635 and 650 nm. Simultaneous measurements with neighboring wavelengths significantly improved the data processing, by increasing the amount of data to eliminate the systematic errors. For langasite crystal La3Ga5SiO14 we measured temperature dependence of the...
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Continuous wave sonar with hyperbolic frequency modulation keyed by pseudo-random sequence
PublicationA CW FM type sounding signal is used in the classical solution of silent sonar. While the signal provides a relatively simple implementation of digital signal processing, and ensures good detection conditions, unfortunately, in the presence of the Doppler effect, distance measurement results tend to be wrong. This is due to the fact that the received signal’s instantaneous frequency value is dependent both on the distance to the...
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An Overview of the Development of a Real-Time System for Endoscopic Video Classification
PublicationThe article presents the results of improving endoscopic image classification algorithms in an effort towards applying them in a real-time diagnosis supporting system. Methods for the detection and removal of personal data are presented and discussed. The currently developed recognition algorithms have been improved in terms of accuracy and performance to make them suitable for a real-life implementation. Their test results are...
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Damage localisation in a stiffened plate structure using a propagating wave
PublicationThe paper presents an application of changes in propagating waves for damage detection in a stiffened aluminium plate. The experimental investigation was conducted on an aluminium plate with riveted two L-shape stiffeners. The wave has been excited with a piezoelectric transducer and measured with the Laser Scanning Doppler Vibrometer. Recorded signals were analysed using the special signal processing techniques developed for damage...
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Combined Single Neuron Unit Activity and Local Field Potential Oscillations in a Human Visual Recognition Memory Task
PublicationGOAL: Activities of neuronal networks range from action potential firing of individual neurons, coordinated oscillations of local neuronal assemblies, and distributed neural populations. Here, we describe recordings using hybrid electrodes, containing both micro- and clinical macroelectrodes, to simultaneously sample both large-scale network oscillations and single neuron spiking activity in the medial temporal lobe structures...
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Deep Instance Segmentation of Laboratory Animals in Thermal Images
PublicationIn this paper we focus on the role of deep instance segmentation of laboratory rodents in thermal images. Thermal imaging is very suitable to observe the behaviour of laboratory animals, especially in low light conditions. It is an non-intrusive method allowing to monitor the activity of animals and potentially observe some physiological changes expressed in dynamic thermal patterns. The analysis of the recorded sequence of thermal...
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EFFICIENT LINE DETECTION METHOD BASED ON 2D CONVOLUTION FILTER
PublicationThe article proposes an efficient line detection method using a 2D convolution filter. The proposed method was compared with the Hough transform, the most popular method of straight lines detection. The developed method is suitable for local detection of straight lines with a slope from -45˚ to 45˚. Also, it can be used for curve detection which shape is approximated with the short straight sections. The new method is characterized...
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Examining Classifiers Applied to Static Hand Gesture Recognition in Novel Sound Mixing System
PublicationThe main objective of the chapter is to present the methodology and results of examining various classifiers (Nearest Neighbor-like algorithm with non-nested generalization (NNge), Naive Bayes, C4.5 (J48), Random Tree, Random Forests, Artificial Neural Networks (Multilayer Perceptron), Support Vector Machine (SVM) used for static gesture recognition. A problem of effective gesture recognition is outlined in the context of the system...
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PROPRIETARY SOFTWARE IN TECHNICAL HIGHER EDUCATION
PublicationThe authors present a relatively easy way to extend the quality of education in professional studies (engineering) on major “Geodesy and Cartography”. They indicate the possibility to deepen students’ knowledge by using in the educational process proprietary software enriching education. The authors use their own experiences, results of the cooperation with employers, as well as the effects of scientific research to introduce into...
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PROPRIETARY SOFTWARE IN TECHNICAL HIGHER EDUCATION
PublicationThe authors present a relatively easy way to extend the quality of education in professional studies (engineering) on major “Geodesy and Cartography”. They indicate the possibility to deepen students’ knowledge by using in the educational process proprietary software enriching education. The authors use their own experiences, results of the cooperation with employers, as well as the effects of scientific research to introduce...
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Audio Content and Crowdsourcing: A Subjective Quality Evaluation of Radio Programs Streamed Online
PublicationRadio broadcasting has been present in our lives for over 100 years. The transmission of speech and music signals accompanies us from an early age. Broadcasts provide the latest information from home and abroad. They also shape musical tastes and allow many artists to share their creativity. Modern distribution involves transmission over a number of terrestrial systems. The most popular are analog FM (Frequency Modulation) and...
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Do the young employees perceive themselves as digitally competent and does it matter?
PublicationPurpose – The study aims to examine the digital competence of young employees (under 30 years of age) who graduated from the technical university. Self-assessment of selected digital competencies was examined along with the determination of a self-efficacy level in the area of using digital competencies. Design/methodology/approach – Quantitative research was conducted using the computer-assisted web interview method on a sample...
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Application of Web-GIS for Dissemination and 3D Visualization of Large-Volume LiDAR Data
PublicationThe increasing number of digital data sources, which allow for semi-automatic collection and storage of information regarding various aspects of life has recently granted a considerable rise in popularity to the term “Big data”. As far as geospatial data is concerned, one of the major sources of Big data are Light Detection And Ranging (LiDAR) scanners, which produce high resolution three-dimensional data on a local scale. The...
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Deep neural networks approach to skin lesions classification — A comparative analysis
PublicationThe paper presents the results of research on the use of Deep Neural Networks (DNN) for automatic classification of the skin lesions. The authors have focused on the most effective kind of DNNs for image processing, namely Convolutional Neural Networks (CNN). In particular, three kinds of CNN were analyzed: VGG19, Residual Networks (ResNet) and the hybrid of VGG19 CNN with the Support Vector Machine (SVM). The research was carried...
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Remote Sensing Methods In the Study of the Impact of Long-Term Process of Sulphur Mining on Environmental Changes of the Carpathian Foreland
PublicationThe paper presents research on the extent of impact of sulphur mining process and post-mining activities upon properties of selected elements of the environment, as well as the assessment of the influence of indirect effects resulting from many years' process of exploitation of sulphur deposits in the areas of the Carpathian Foreland (south-east Poland). Within the scope of research conducted, the assessment of the extent of...
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Visual Detection of People Movement Rules Violation in Crowded Indoor Scenes
PublicationThe paper presents a camera-independent framework for detecting violations of two typical people movement rules that are in force in many public transit terminals: moving in the wrong direction or across designated lanes. Low-level image processing is based on object detection with Gaussian Mixture Models and employs Kalman filters with conflict resolving extensions for the object tracking. In order to allow an effective event...
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3D Hand Shape Modeling for Automatic Assessing Motor Performance in Parkinson's Disease
PublicationIn this paper a method for hand pattern processing to create a 3D hand model is presented. By applying a complete hand armature to the model obtained, an interpolation of three motor tests for an individual Parkinson's disease patient can be performed. To obtain the 3D hand model the top view of the hand from a web cam is analyzed. The hand contour is examined to find characteristic points that allows for dividing hand image into...
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The instantaneous frequency rate spectogram
PublicationAn accelerogram of the instantaneous phase of signal components referred to as an instantaneous frequency rate spectrogram (IFRS) is presented as a joint time-frequency distribution. The distribution is directly obtained by processing the short-time Fourier transform (STFT) locally. A novel approach to amplitude demodulation based upon the reassignment method is introduced as a useful by-product. Additionally, an estimator of energy...
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Statistically efficient smoothing algorithm for time-varying frequency estimation
PublicationThe problem of extraction/elimination of a nonstationary sinusoidal signal from noisy measurements is considered. This problem is usually solved using adaptive notch filtering (ANF) algorithms. It is shown that the accuracy of frequency estimates can be significantly increased if the results obtained from ANF are backward-time filtered by an appropriately designed lowpass filter. The resulting adaptive notch smoothing (ANS) algorithm...
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BETWEEN IDEA AND INTERPRETATION - DESIGN PROCESS AUGMENTATION
PublicationThe following paper investigates the idea of reducing the human digital intervention to a minimum during the advanced design process. Augmenting the outcome attributes beyond the designer's capabilities by computational design methods, data collection, data computing and digital fabrication, altogether imitating the human design process. The primary technical goal of the research was verification of restrictions and abilities used...
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Improving automatic surveillance by sound analysis
PublicationAn automatic surveillance system, based on event detection in the video image can be improved by implementing algorithms for audio analysis. Dangerous or illegal actions are often connected with distinctive sound events like screams or sudden bursts of energy. A method for detection and classification of alarming sound events is presented. Detection is based on the observation of sudden changes in sound level in distinctive sub-bands...
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Imaging polarimeter with high-accuracy measuring principles in crystal optics
PublicationAn imaging polarimeter based on the principles of high-accuracy polarimetry well known in crystal optics is proposed. The application of scientific digital cameras for performance light measurements leads to precise data on polarizers quality, i.e., maps of extinction ratio and transmission axis. Processing of numerous images, acquired at various settings in the polarizer-sample-analyser system, allows to determine the two-dimensional...
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Automatic sound source localization in disturbing conditions using acoustic vector sensors
PublicationA concept, practical realization and applications of a passive acoustic radar to automatic localization and tracking of sound sources in disturbing conditions were presented in the paper. The device consists of the new kind of multichannel miniature sound intensity sensors and a group of digital signal processing algorithms. The sensitivity of the realized acoustic radar was examined in free sound field. Several kinds of sound...
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Low-Level Music Feature Vectors Embedded as Watermarks
PublicationIn this paper a method consisting in embedding low-level music feature vectors as watermarks into a musical signal is proposed. First, a review of some recent watermarking techniques and the main goals of development of digital watermarking research are provided. Then, a short overview of parameterization employed in the area of Music Information Retrieval is given. A methodology of non-blind watermarking applied to music-content...
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Acoustic Processor of the Mine Countermeasure Sonar
PublicationThis 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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Generalized adaptive notch smoothers for real-valued signals and systems
PublicationSystems with quasi-periodically varying coefficients can be tracked using the algorithms known as generalized adaptive notch filters (GANFs). GANF algorithms can be considered an extension, to the system case, of classical adaptive notch filters (ANFs). We show that estimation accuracy of the existing algorithms, as well as their robustness to the choice of design parameters, can be considerably improved by means of compensating...
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Visual Object Tracking System Employing Fixed and PTZ Cameras
PublicationThe paper presents a video monitoring system utilizing fixed and PTZ cameras for tracking of moving objects. First type of camera provides image for background modelling, being employed for foreground objects localization. Estimated objects locations are then utilised for steering of PTZ cameras when observing targeted objects with high close-ups. Objects are classified into several classes, then basic event detection is being...
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Gesture-based computer control system applied to the interactive whiteboard
PublicationIn the paper the gesture-based computer control system coupled with the dedicated touchless interactive whiteboard is presented. The system engineered enables a user to control any top-most computer application by using one or both hands gestures. First, a review of gesture recognition applications with a focus on methods and algorithms applied is given. Hardware and software solution of the system consisting of a PC, camera, multimedia...
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Gesture-based computer control system applied to the interactive whiteboard
PublicationIn the paper the gesture-based computer control system coupled with the dedicated touchless interactive whiteboard is presented. The system engineered enables a user to control any top-most computer application by using one or both hands gestures. First, a review of gesture recognition applications with a focus on methods and algorithms applied is given. Hardware and software solution of the system consisting of a PC, camera, multimedia...
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Examining Quality of Hand Segmentation Based on Gaussian Mixture Models
PublicationResults of examination of various implementations of Gaussian mix-ture models are presented in the paper. Two of the implementations belonged to the Intel’s OpenCV 2.4.3 library and utilized Background Subtractor MOG and Background Subtractor MOG2 classes. The third implementation presented in the paper was created by the authors and extended Background Subtractor MOG2 with the possibility of operating on the scaled version of...
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Hand gesture recognition supported by fuzzy rules and Kalman filters
PublicationThe paper presents a system based on camera and multimediaprojector enabling a user to control computer applications by dynamic hand gestures. Gesture recognition methodology based on representing hand movement trajectory by motion vectors analysed using fuzzy rule-based inference is first given. For effective hand position tracking Kalman filters are employed. The system engineered is developed using J2SE and C++/OpenCV technology....
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An Analysis of Uncertainty and Robustness of Waterjet Machine Positioning Vision System
PublicationThe paper presents a new Automatic Waterjet Positioning Vision System (AWPVS) and investigates components of workpiece positioning accuracy. The main purpose of AWPVS is to precisely identify the position and rotation of a workpiece placed on a waterjet machine table. Two webcams form a basis for the system, and constitute its characteristics. The proposed algorithm comprises various image processing techniques to assure a required...
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Exception handling model influence factors for discributed systems. W: Proceedings. PPAM 2003. Parallel Processing and Applied Mathematics. 5th In- ternational Conference. Częstochowa, 7-10 September 2003.Model obsługi wyjątków uwzględniający wpływ czynników systemu rozproszonego.
PublicationSpecyfikacja programu jest jasno określona w systemach sekwencyjnych, gdzie posiada standardowe i wyjątkowe przejścia. Praca przedstawia rozszerzony model specyfikacji systemu w środowiskach rozproszonych uwzględniający szereg specyficznych czynników. Model zawiera analizę specyfikacji pod kątem obsługi wyjątków dla rozproszonych danych oraz komunikacji międzyprocesorowej. Ogólny model został zaimplementowany w środowisku...
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Video content analysis in the urban area telemonitoring system
PublicationThe task of constant monitoring of video streams from a large number of cameras and reviewing the recordings in order to find a specified event requires a considerable amount of time and effort from the system operators and it is prone to errors. A solution to this problem is an automatic system for constant analysis of camera images being able to raise an alarm if a predefined event is detected. The chapter presents various aspects...
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Frequency Guided Generalized Adaptive Notch Filtering - Tracking Analysis and Optimization
PublicationGeneralized adaptive notch filters (GANFs) are estimators of coefficients of quasi-periodically time-varying systems, encountered e.g., in RF applications when Doppler effect takes place. Current state of the art GANFs can deliver highly accurate estimates of system variations’ frequency, but underperform in terms of accuracy of system coefficient estimates. The paper proposes a novel multistage GANF with improved coefficient...
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LOS and NLOS identification in real indoor environment using deep learning approach
PublicationVisibility conditions between antennas, i.e. Line-of-Sight (LOS) and Non-Line-of-Sight (NLOS) can be crucial in the context of indoor localization, for which detecting the NLOS condition and further correcting constant position estimation errors or allocating resources can reduce the negative influence of multipath propagation on wireless communication and positioning. In this paper a deep learning (DL) model to classify LOS/NLOS...
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Implementation of Addition and Subtraction Operations in Multiple Precision Arithmetic
PublicationIn this paper, we present a digital circuit of arithmetic unit implementing addition and subtraction operations in multiple-precision arithmetic (MPA). This adder-subtractor unit is a part of MPA coprocessor supporting and offloading the central processing unit (CPU) in computations requiring precision higher than 32/64 bits. Although addition and subtraction operations of two n-digit numbers require O(n) operations, the efficient...
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Pupil detection supported by Haar feature based cascade classifier for two-photon vision examinations
PublicationThe aim of this paper is to present a novel method, called Adaptive Edge Detection (AED), of extraction of precise pupil edge coordinates from eye image characterized by reflections of external illuminators and laser beams. The method is used for monitoring of pupil size and position during psychophysical tests of two-photon vision performed by dedicated optical set-up. Two-photon vision is a new phenomenon of perception of short-pulsed...
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Digitalization of Building Site Management in the Construction Industry
PublicationWith Industry 4.0, a digital transformation has started in the construction industry. However, 4.0 technologies have difficulties in the integration of digital systems due to the diversity and complexity of the processes in the construction industry. Multidisciplinary work in architectural projects and the need for high productivity require digital renovation planning in the construction industry. The application of the technologies...
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Quality of Cryptocurrency Mining on Previous Generation NVIDIA GTX GPUs
PublicationCurrently, there is a lot of previous generation NVIDIA GTX graphical processing units (GPUs) available on the market, which were ousted from by next-gen RTX units. Due to this fact, numerous fully-operational devices remain underused, which are available at an affordable price. First, this paper presents an analysis of the cryptocurrency market. Next, in this context, the results of research on the performance of NVIDIA graphics...
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Software-Defined NB-IoT Uplink Framework - The Design, Implementation and Use Cases
PublicationIn the radiocommunication area, we may observe a rapid growth of new technology, such as 5G. Moreover, all the newly introduced radio interfaces, e.g., narrowband Internet of Things (NB-IoT), are strongly dependent on the software. Hence, the radiocommunication software development and optimization, as well as the 3GPP technical specification, should be introduced at the academic level of education. In this paper, a software-defined...
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Acoustic Processor of the MCM Sonar
PublicationThis 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, a modernised 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...
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REVIEW OF CURRENT RESEARCH ON CHITOSAN AS A RAW MATERIAL IN THREE-DIMENSIONAL PRINTING TECHNOLOGY IN BIOMEDICAL APPLICATIONS
PublicationThree-dimensional (3D) biomaterial manufacturing strategies show an extraordinary driving force for the development of innovative solutions in the biomedical sector, including drug delivery systems, disease modelling and tissue and organ engineering. Due to its remarkable and promising biological and structural properties, chitosan has been widely studied for decades in several potential applications in the biomedical field. However,...
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Towards a Smart Sustainable City Roadmap
PublicationThis workshop of the CAP4CITY (Erasmus+ Strengthening Governance Capacity for Smart Sustainable Cities) project is to promote and stimulate the discussion and networking in the area of Digital Government. Smart Sustainable Cities and related concepts of Digital, Intelligent and Smart Cities represent a progression of how cities around the world apply digital technology to serve their populations, pursue sustainable socio-economic...
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Multibeam Echosounder and LiDAR in Process of 360-Degree Numerical Map Production for Restricted Waters with HydroDron
PublicationIn order to increase the safety of inland navigation and facilitate the monitoring of the coastal zone of restricted waters, a model of multi-sensory fusion of data from hydroacoustic and optoelectronic systems mounted on the autonomous survey vessel HydroDron will be developed. In the research will be used the LiDAR laser scanner and multibeam echosounder. To increase the visual quality and map accuracy, additionally side scan...
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Bimodal classification of English allophones employing acoustic speech signal and facial motion capture
PublicationA method for automatic transcription of English speech into International Phonetic Alphabet (IPA) system is developed and studied. The principal objective of the study is to evaluate to what extent the visual data related to lip reading can enhance recognition accuracy of the transcription of English consonantal and vocalic allophones. To this end, motion capture markers were placed on the faces of seven speakers to obtain lip...
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Instrument detection and pose estimation with rigid part mixtures model in video-assisted surgeries
PublicationLocalizing instrument parts in video-assisted surgeries is an attractive and open computer vision problem. A working algorithm would immediately find applications in computer-aided interventions in the operating theater. Knowing the location of tool parts could help virtually augment visual faculty of surgeons, assess skills of novice surgeons, and increase autonomy of surgical robots. A surgical tool varies in appearance due to...
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Seafloor Characterisation and Imaging Using Multibeam Sonar Data
PublicationThe approach to seafloor characterisation and imaging is presented. It relies on the combined, concurrent use of several techniques of multibeam sonar data processing. The first one is based on constructing the grey-level sonar images of seabed using the backscattering strength calculated for the echoes received in the consecutive beams. Then, the set of parameters describing the local region of sonar image is calculated. The second...
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Visual Features for Endoscopic Bleeding Detection
PublicationAims: To define a set of high-level visual features of endoscopic bleeding and evaluate their capabilities for potential use in automatic bleeding detection. Study Design: Experimental study. Place and Duration of Study: Department of Computer Architecture, Faculty of Electronics, Telecommunications and Informatics, Gdansk University of Technology, between March 2014 and May 2014. Methodology: The features have...