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Wyniki wyszukiwania dla: classification

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Wyniki wyszukiwania dla: classification

  • Swarm Algorithms in Modern Engineering Optimization Problems

    Publikacja

    Complexity of today engineering problems is constantly increasing. Scientists no longer are facing issues, for which simple, mathematical programming methods are sufficient. Issues like autonomic vehicle navigation or classification are considered to be challenging, and although there exist valid means to solve them, in some cases there still is some place for improvement. With emergence of a new type of optimization techniques...

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  • The Method of a Two-Level Text-Meaning Similarity Approximation of the Customers’ Opinions

    The method of two-level text-meaning similarity approximation, consisting in the implementation of the classification of the stages of text opinions of customers and identifying their rank quality level was developed. Proposed and proved the significance of major hypotheses, put as the basis of the developed methodology, notably about the significance of suggestions about the existence of analogies between mathematical bases of...

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  • Layered background modeling for automatic detection of unattended objects in camera images

    Publikacja

    - Rok 2011

    An algorithm for automatic detection of unattended objects in video camera images is presented. First, background subtraction is performed, using an approach based on the codebook method. Results of the detection are then processed by assigning the background pixels to time slots, based on the codeword age. Using this data, moving objects detected during a chosen period may be extracted from the background model. The proposed approach...

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  • Geotechnical characterization of soft soil deposits in Northern Poland

    This paper presents a geotechnical characterization of deltaic soft soil deposits in the Vistula Marshlands, northern Poland. It shows the limited applicability of organic soil classifications based on Cone Penetration Tests (CPTU) and Dilatometer Tests (DMT). None of the in-situ-based classifications correctly identifies peat. Analysis of the behaviour of contractive/dilative soil layers according to Robertson's updated classification...

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  • Active Dynamic Thermography in Medical Diagnostics

    Publikacja

    This is an overview of active thermal imaging methods in medical diagnostics using external thermal stimulation. In this chapter, several clinical cases diagnosed using the active dynamic thermography method, ADT, are presented. Features of this technology are discussed and main advantages underlined. Applications in skin burn diagnostics and quantitative evaluation leading to modern classification of burned patients for further...

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  • Machine Learning in Multi-Agent Systems using Associative Arrays

    Publikacja

    - PARALLEL COMPUTING - Rok 2018

    In this paper, a new machine learning algorithm for multi-agent systems is introduced. The algorithm is based on associative arrays, thus it becomes less complex and more efficient substitute of artificial neural networks and Bayesian networks, which is confirmed by performance measurements. Implementation of machine learning algorithm in multi-agent system for aided design of selected control systems allowed to improve the performance...

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  • Analysis of 2D Feature Spaces for Deep Learning-based Speech Recognition

    Publikacja

    - JOURNAL OF THE AUDIO ENGINEERING SOCIETY - Rok 2018

    convolutional neural network (CNN) which is a class of deep, feed-forward artificial neural network. We decided to analyze audio signal feature maps, namely spectrograms, linear and Mel-scale cepstrograms, and chromagrams. The choice was made upon the fact that CNN performs well in 2D data-oriented processing contexts. Feature maps were employed in the Lithuanian word recognition task. The spectral analysis led to the highest word...

  • Road surface roughness estimation employing integrated position and acceleration sensor

    Publikacja

    Assessment of a surface quality being an essential task for the authorities supervising the roads provides the subject of the paper. Information about riding quality of a pavement, important for drivers, both in terms of their comfort and safety is collected during experiments employing mobile sensors. The paper describes the use of a miniature position and acceleration sensor for evaluation of the roughness of the road surface....

  • MACHINE LEARNING APPLICATIONS IN RECOGNIZING HUMAN EMOTIONS BASED ON THE EEG

    Publikacja
    • A. Kastrau
    • M. Koronowski
    • M. Liksza
    • P. Jasik

    - Rok 2021

    This study examined the machine learning-based approach allowing the recognition of human emotional states with the use of EEG signals. After a short introduction to the fundamentals of electroencephalography and neural oscillations, the two-dimensional valence-arousal Russell’s model of emotion was described. Next, we present the assumptions of the performed EEG experiment. Detail aspects of the data sanitization including preprocessing,...

  • Video content analysis in the urban area telemonitoring system

    Publikacja

    The 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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  • Preliminary safety assessment of Polish interchanges

    Publikacja

    - Archives of Transport - Rok 2021

    Interchanges are a key and the most complex element of a road infrastructure. The safety and functionality of interchanges determine the traffic conditions and safety of the entire road network. This applies particularly to motorways and express-ways, for which they are the only way to access and exchange traffic. A big problem in Poland is the lack of comprehensive tools for designers at individual stages of the design process....

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  • Multispectral impedance quality testing of coil-coating system using principal component analysis

    The task of quality checking of the coil-coated system was undertaken using impedance spectroscopy. In order to properly characterize the system the new impedance spectrum was calculated as an averaged result of 12 experimental spectra obtained from 12 different places of the sample at the same time of immersion in 3% of NaCl. The experimental spectra were recorded for a 24-h period at 1 h intervals between starting points of each...

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  • The properties, functions and use of selenium compounds in living organisms

    Selenium occurs in the environment in inorganic and organic compounds. For many years it was regarded as a toxic element, causing numerous illnesses and diseases. But research in the last 50 years has revealed a "bright side" to this element, especially as a component of selenoproteins, selenium makes a significant contribution to the health of humans and animals. The selenium content in an organism depends on its concentration...

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  • Acoustic Processor of the Mine Countermeasure Sonar

    This 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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  • On Sample Rate Conversion Based on Variable Fractional Delay Filters

    The sample rate conversion algorithm based on variable fractional delay filters is often used if the resampling ratio cannot be expressed as the ratio of small integer numbers or if it is not constant. The main advantage of such solution is that it allows for arbitrary resampling ratios which can even be changed during the resampling process. In this paper a discussion on influence of different approaches to fractional filter...

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  • Devices for the production of reference gas mixtures

    For many years there has been growing demand for gaseous reference materials, which is connected with development in many fields of science and technology. As a result, new methodological and instrumental solutions appear that can be used for this purpose. Appropriate quality assurance/quality control (QA/QC) must be used to make sure that measurement data are a reliable source of information. Reference materials are a significant...

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  • An Approach to Bass Enhancement in Portable Computers Employing Smart Virtual Bass Synthesis Algorithms

    Publikacja

    The aim of this paper is to present a novel approach to the Virtual Bass Synthesis (VBS) algorithms applied to portable computers. The developed algorithms are related to intelligent, rule-based setting of synthesis parameters according to music genre of an audio excerpt and to the type of a portable device in use. To find optimum synthesis parameters of the VBS algorithms, subjective listening tests based on a parametric procedure...

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  • Security aspects in functional safety analysis

    A security level of distributed control and protection system may have a significant impact on the results of functional safety analysis. However, the issue of integrating the safety and security aspects is difficult and usually is neglected during the functional safety analysis. This article presents a method of functional safety analysis which takes into consideration a concept of integrating these two aspects. It is based on...

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  • An extension to the FEEDB Multimodal Database of Facial Expressions and Emotions

    Publikacja
    • M. Szwoch
    • L. Marco-gimenez
    • M. Arevalillo-herráez
    • A. Ayesh

    - Rok 2015

    FEEDB is a multimodal database that contains recordings of people expressing different emotions, captured by using a Microsoft Kinect sensor. Data were originally provided in the device’s proprietary format (XED), requiring both the Microsoft Kinect Studio application and a Kinect sensor attached to the system to use the files. In this paper, we present an extension of the database. For a selection of recordings, we also provide...

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  • Multi-Aspect Quality Assessment Of Mobile Image Classifiers For Companion Applications In The Publishing Sector

    Publikacja

    - Rok 2021

    The paper presents the problem of quality assessment of image classifiers used in mobile phones for complimentary companion applications. The advantages of using this kind of applications have been described and a Narrator on Demand (NoD) functionality has been described as one of the examples, where the application plays an audio file related to a book page that is physically in front of the phone's camera. For such a NoD application,...

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  • Introduction to the special issue on machine learning in acoustics

    Publikacja
    • Z. Michalopoulou
    • P. Gerstoft
    • B. Kostek
    • M. A. Roch

    - Journal of the Acoustical Society of America - Rok 2021

    When we started our Call for Papers for a Special Issue on “Machine Learning in Acoustics” in the Journal of the Acoustical Society of America, our ambition was to invite papers in which machine learning was applied to all acoustics areas. They were listed, but not limited to, as follows: • Music and synthesis analysis • Music sentiment analysis • Music perception • Intelligent music recognition • Musical source separation • Singing...

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  • RSS-Based DoA Estimation for ESPAR Antennas Using Support Vector Machine

    In this letter, it is shown how direction-of-arrival (DoA) estimation for electronically steerable parasitic array radiator (ESPAR) antennas, which are designed to be integrated within wireless sensor network nodes, can be improved by applying support vector classification approach to received signal strength (RSS) values recorded at an antenna's output port. The proposed method relies on ESPAR antenna's radiation patterns measured...

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  • MACHINE LEARNING SYSTEM FOR AUTOMATED BLOOD SMEAR ANALYSIS

    In this paper the authors propose a decision support system for automatic blood smear analysis based on microscopic images. The images are pre-processed in order to remove irrelevant elements and to enhance the most important ones - the healthy blood cells (erythrocytes) and the pathologic (echinocytes). The separated blood cells are analyzed in terms of their most important features by the eigenfaces method. The features are the...

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  • Intelligent system supporting diagnosis of malignant melanoma

    Malignant melanomas are the most deadly type of skin cancers. Early diagnosis is a key for successful treatment and survival. The paper presents the system for supporting the process of diagnosis of skin lesions in order to detect a malignant melanoma. The paper describes the development process of an intel-ligent system purposed for the diagnosis of malignant melanoma. Presented sys-tem can be used as a decision support system...

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  • Comparison of Deep Neural Network Learning Algorithms for Mars Terrain Image Segmentation

    This paper is dedicated to the topic of terrain recognition on Mars using advanced techniques based on the convolutional neural networks (CNN). The work on the project was conducted based on the set of 18K images collected by the Curiosity, Opportunity and Spirit rovers. The data were later processed by the model operating in a Python environment, utilizing Keras and Tensorflow repositories. The model benefits from the pretrained...

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  • Redukcja czasu analizy MZP przez ograniczenie rozmiaru rozwiązania

    Analiza drzew niezdatności jest uznaną metodą analizy bezpieczeństwa systemów. Notacja ECSDM pozwala definiować zależności czasowe między zdarzeniami drzewa oraz przeanalizować je w celu określenia zależności pomiędzy zdarzeniami z Minimalnych Zbiorów Przyczyn (MZP). Dzięki wprowadzeniu klasyfikacji zdarzeń z MZP można wyodrębnić zależności czasowe istotne dla zapobiegania wywoływania hazardu przez konkretny MZP. Pozostałe zależności...

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  • Zastosowanie elektronicznych zmysłów w analizie żywności. Zastosowanie elektronicznego języka w analizie żywności.

    W dzisiejszych czasach konsumenci zwracają dużą uwagę na takie cechy żywności jak: zapach, smak i wygląd. Ze względu na to naukowcy od wielu lat podejmują próby naśladowania ludzkich narządów zmysłów za pomocą urządzeń określanych jako elektroniczne zmysły. Zaliczamy do nich elektroniczny nos i język oraz komputerowy system rozróżnienia barw i kształtów. Elektroniczny język znany również jako sztuczny język lub czujnik smaku,...

  • INWESTYCJE ALTERNATYWNE – OPŁACALNOŚĆ A RYZYKO

    Publikacja

    - Rok 2015

    W rozprawie określono pojęcie oraz miejsce inwestycji alternatywnych na rynku inwestycyjnym. Wskazane zostały atrybuty tych inwestycji. Zbudowano klasyfikację inwestycji alternatywnych w podziale na kategorie oraz typy wraz ze wskazaniem powiązań pomiędzy poszczególnymi produktami. Dokonano autorskiego podziału analizowanych inwestycji na aktywne i pasywne. Zbadano stopę zwrotu i ryzyko pięćdziesięciu inwestycji alternatywnych,...

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  • DEEP LEARNING BASED ON X-RAY IMAGING IMPROVES COXARTHROSIS DETECTION

    Publikacja
    • M. Maj
    • J. Borkowski
    • J. Wasilewski
    • S. Hrynowiecka
    • A. Kastrau
    • M. Liksza
    • P. Jasik
    • M. Treder

    - Rok 2022

    Objective: The purpose of the study was to create an Artificial Neural Network (ANN) based on X-ray images of the pelvis, as an additional tool to automate and improve the diagnosis of coxarthrosis. The research is focused on joint space narrowing, which is a radiological symptom showing the thinning of the articular cartilage layer, which is translucent to X-rays. It is the first and the most important of the radiological signs...

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  • Rozpoznawanie oraz lokalizacja w obrazie przewodów linii wysokiego napięcia

    W pracy przedstawiono opracowany algorytm rozpoznawania oraz lokalizacji przewodów linii wysokiego napięcia na podstawie obrazu horyzontalnego. Procedura detekcji przewodu została podzielona na trzy etapy. Pierwszy etap zawiera algorytm wykrywania krawędzi wykazujący największą czułość na krawędzie poziome, a jednocześnie brak czułości na krawędzie pionowe. Efektem jest znaczna redukcja liczby wykrytych krawędzi w porównaniu do...

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  • New Two-center Ellipsoidal Basis Function Neural Network for Fault Diagnosis of Analog Electronic Circuits

    In the paper a new fault diagnosis-oriented neural network and a diagnostic method for localization of parametric faults in Analog Electronic Circuits (AECs) with tolerances is presented. The method belongs to the class of dictionary Simulation Before Test (SBT) methods. It utilizes dictionary fault signatures as a family of identification curves dispersed around nominal positions by component tolerances of the Circuit Under Test...

  • Application tool for IP QoS network design

    Publikacja

    - Rok 2010

    Despite the fact that differentiated-service-aware network implementation has been a widely discussed topic for quite some time, network design still proofs nontrivial. Well developed software could put an end to network designer's problems. This chapter describes work, which has been aimed at creating a comprehensive network design tool, offering a fair range of functionality and high reliability. The presented tool is able to...

  • Multibeam sonar data processing for seafloor characterisation

    Publikacja

    - Rok 2011

    The 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 of seabed, 2) the 3D model of the seabed surface which consist of (x, y, z) points, 3) the set of time domain echo envelopes corresponding to several beams. The proposed method has...

  • Selecting Features with SVM

    Publikacja

    A common problem with feature selection is to establish how many features should be retained at least so that important information is not lost. We describe a method for choosing this number that makes use of Support Vector Machines. The method is based on controlling an angle by which the decision hyperplane is tilt due to feature selection. Experiments were performed on three text datasets generated from a Wikipedia dump. Amount...

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  • In uence of Low-Level Features Extracted from Rhythmic and Harmonic Sections on Music Genre Classi cation

    Publikacja

    - Rok 2013

    We present a comprehensive evaluation of the infuence of 'harmonic' and rhythmic sections contained in an audio file on automatic music genre classi cation. The study is performed using the ISMIS database composed of music files, which are represented by vectors of acoustic parameters describing low-level music features. Non-negative Matrix Factorization serves for blind separation of instrument components. Rhythmic components...

  • Acoustic Processor of the MCM Sonar

    This 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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  • The enantiomeric determination of chloro-precursors of methamphetamine

    Publikacja

    - Rok 2011

    Impurity profiling and classification of seized methamphetamine may supply valuable information with respect to the conditions and the chemicals used in the illicit methamphetamine manufacture and may provide information on the original source of the sample. Determination of the stereochemical makeup of forensic samples is important as well for the same reasons. Laboratories in many places are engaged in clandestine manufacture...

  • A procedure for the determination of dichloromethane and tetrachloroethene in water using pervaporation and gas chromatography

    Publikacja

    - CHEMICAL PAPERS - Rok 2011

    In the present study, pervaporation was applied to the determination of tetrachloroethene (PCE) and dichloromethane (DCM) in liquid samples. PCE is the most commonly used solvent in dry-cleaning processes. PCE belongs to group 2A of carcinogens (probably carcinogenic to humans) according to the classification of the International Agency for Research on Cancer (IARC). DCM is also widely used as an industrial solvent for the purification...

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  • THE SCIENTIFIC CAPACITY AS AN INNOVATION DETERMINANT OF THE POLISH REGIONS

    Every Polish region (in the paper understood as a voivodship) is an inspiring ground for comparative studies on the national as well as European scale, i.e. with regard to the administrative units of the other European countries. The aim of the article is to advance the conclusions concerning the Regional Innovation Scoreboard – a European instrument applied to examine the innovation capacity of European regions – with the issues...

  • Multimodal Approach For Polysensory Stimulation And Diagnosis Of Subjects With Severe Communication Disorders

    Publikacja

    is evaluated on 9 patients, data analysis methods are described, and experiments of correlating Glasgow Coma Scale with extracted features describing subjects performance in therapeutic exercises exploiting EEG and eyetracker are presented. Performance metrics are proposed, and k-means clusters used to define concepts for mental states related to EEG and eyetracking activity. Finally, it is shown that the strongest correlations...

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  • A comparative study of English viseme recognition methods and algorithms

    An elementary visual unit – the viseme is concerned in the paper in the context of preparing the feature vector as a main visual input component of Audio-Visual Speech Recognition systems. The aim of the presented research is a review of various approaches to the problem, the implementation of algorithms proposed in the literature and a comparative research on their effectiveness. In the course of the study an optimal feature vector construction...

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  • Multibeam data processing for 3D object shape reconstruction

    Publikacja

    The technology of hydroacoustic scanning offers an efficient and widely-used source of geospatial information regarding underwater environments, providing measurement data which usually have the structure of irregular groups of points known as point clouds. Since this data model has known disadvantages, a different form of representation based on representing surfaces with simple geometric structures, such as edges and facets,...

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  • Automatic Clustering of EEG-Based Data Associated with Brain Activity

    The aim of this paper is to present a system for automatic assigning electroencephalographic (EEG) signals to appropriate classes associated with brain activity. The EEG signals are acquired from a headset consisting of 14 electrodes placed on skull. Data gathered are first processed by the Independent Component Analysis algorithm to obtain estimates of signals generated by primary sources reflecting the activity of the brain....

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  • Explainable AI for Inspecting Adversarial Attacks on Deep Neural Networks

    Deep Neural Networks (DNN) are state of the art algorithms for image classification. Although significant achievements and perspectives, deep neural networks and accompanying learning algorithms have some important challenges to tackle. However, it appears that it is relatively easy to attack and fool with well-designed input samples called adversarial examples. Adversarial perturba-tions are unnoticeable for humans. Such attacks...

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  • Visual Content Learning in a Cognitive Vision Platform for Hazard Control (CVP-HC)

    Publikacja

    - CYBERNETICS AND SYSTEMS - Rok 2019

    This work is part of an effort for the development of a Cognitive Vision Platform for Hazard Control (CVP-HC) for applications in industrial workplaces, adaptable to a wide range of environments. The paper focuses on hazards resulted from the nonuse of personal protective equipment (PPE). Given the results of previous analysis of supervised techniques for the problem of classification of a few PPE (boots, hard hats, and gloves...

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  • Nanoparticles: Synthesis, characteristics, and applications in analytical and other sciences

    Publikacja

    Nanoparticles (NPs) are widely employed in different research areas, ranging from analytical chemistry and environmental science to medicine, the agriculture and pharmaceutical industry. This is mainly due to the unique characteristics of NPs and the novelty they introduce in such applications. In analytical chemistry, the role of NPs can differ depending on the nature of the steps involved in analytical process. NPs are probably...

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  • Improving the Survivability of Carrier Networks to Large-Scale Disasters

    Publikacja
    • A. de Sousa
    • J. Rak
    • F. Barbosa
    • D. Santos
    • D. Mehta

    - Rok 2020

    This chapter is dedicated to the description of methods aiming to improve the survivability of carrier networks to large-scale disasters. First, a disaster classification and associated risk analysis is described, and the disaster-aware submarine fibre-optic cable deployment is addressed aiming to minimize the expected costs in case of natural disasters. Then, the chapter addresses the improvement of the network connectivity resilience...

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  • Monitoring the BTEX Volatiles during 3D Printing with Acrylonitrile Butadiene Styrene (ABS) Using Electronic Nose and Proton Transfer Reaction Mass Spectrometry

    We describe a concept study in which the changes of concentration of benzene, toluene, ethylbenzene, and xylene (BTEX) compounds and styrene within a 3D printer enclosure during printing with different acrylonitrile butadiene styrene (ABS) filaments were monitored in real-time using a proton transfer reaction mass spectrometer and an electronic nose. The quantitative data on the concentration of the BTEX compounds, in particular...

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  • A comparative study of English viseme recognition methods and algorithm

    An elementary visual unit – the viseme is concerned in the paper in the context of preparing the feature vector as a main visual input component of Audio-Visual Speech Recognition systems. The aim of the presented research is a review of various approaches to the problem, the implementation of algorithms proposed in the literature and a comparative research on their effectiveness. In the course of the study an optimal feature vector...

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  • Detection of apple in orange juice using ultra-fast gas chromatography

    Publikacja

    The determination of authenticity is an increasingly important issue for food quality and safety. The use of an electronic nose based on ultra-fast gas chromatography technique ensures rapid analysis of the volatile compounds from food products. Due to the fact that this technique enables chemical profiling of agricultural products, it can be an effective tool for authentication when combined with chemometrics. In this article...

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