2018 - Repozytorium publikacji - Politechnika Gdańska

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Assessment of the Impact of GNSS Processing Strategies on the Long-Term Parameters of 20 Years IWV Time Series
- Zofia Baldysz
- Grzegorz Nykiel
- Mariusz Figurski
- Andrzej Araszkiewicz
2018 Pełny tekst Remote Sensing
Advanced processing of collected global navigation satellite systems (GNSS) observations allows for the estimation of zenith tropospheric delay (ZTD), which in turn can be converted to the integrated water vapour (IWV). The proper estimation of GNSS IWV can be affected by the adopted GNSS processing strategy. To verify which of its elements cause deterioration and which improve the estimated GNSS IWV, we conducted eight reprocessings of 20 years of GPS observations (01.1996–12.2015). In each of them, we applied a different mapping function, the zenith hydrostatic delay (ZHD) a priori value, the cut-off angle, software, and the positioning method. Obtained in such a way, the ZTD time series were converted to the IWV using the meteorological parameters sourced from the ERA-Interim. Then, based on them, the long-term parameters were estimated and compared to those obtained from the IWV derived from the radio sounding (RS) observations. In this paper, we analyzed long-term parameters such as IWV mean values, linear trends, and amplitudes of annual and semiannual oscillations. A comparative analysis showed, inter alia, that in terms of the investigation of the IWV linear trend the precise point positioning (PPP) method is characterized by higher accuracy than the differential one. It was also found that using the GPT2 model and the higher elevation mask brings benefits to the GNSS IWV linear trend estimation.
Assessment of Therapeutic Progress After Acquired Brain Injury Employing Electroencephalography and Autoencoder Neural Networks
- Adam Kurowski
- Andrzej Czyżewski
2018
A method developed for parametrization of EEG signals gathered from participants with acquired brain injuries is shown. Signals were recorded during therapeutic session consisting of a series of computer assisted exercises. Data acquisition was performed in a neurorehabilitation center located in Poland. The presented method may be used for comparing the performance of subjects with acquired brain injuries (ABI) who are involved in concentration training program. It may also allow for an assessment of relative difference in performance of two participants involved to exercises by comparing parameters derived from EEG signals acquired in the course of therapeutic sessions. The parametrization method is based on autoencoder neural networks. The efficiency of parameters extracted employing the algorithm was compared to parameters derived from the spectrum of EEG signal. As it was confirmed by achieved results, the presented autoencoder-based method may be applied to predict ABI subjects’ performance in attention training sessions.
Assessment of Trace Metals Leaching During Rainfall Events from Building Rooftops with Different Types of Coverage – Case Study
- Nicole Nawrot
- Ewa Wojciechowska
2018 Pełny tekst Journal of Ecological Engineering
Runoff water is an important medium transporting various types of pollution originating from the atmosphere and washed out from roofing materials. The study presents a quality assessment of runoff from different roofs in the context of trace metal concentrations. The analysed rooftops were covered with copper, tar paper and ceramic tile. The quality of the rain water collected at the same time satisfies the demands of the first grade of cleanliness according to (Journal of Laws, 2016 item1187). The highest content of copper was leached from the copper roof, containing 10.23 mg∙dm-3. In the case of zinc, the highest concentration of 15.52 mg∙dm-3 was present in the runoff from the roof covered with thermally bonded tar paper. The amount of trace metals in the ceramic roof runoff was the lowest and only for zinc slightly exceeded 1.47 mg∙dm-3 – the value determined for II class of purity. In the paper, the different levels of heavy metals leaching from different roofing materials have been confirmed.
ASYNCHRONICZNE METODY RADIOLOKALIZACYJNE
- Jacek Stefański
2018
W pracy przedstawiono wybrane problemy lokalizowania obiektów w asynchronicznych sieciach radiowych. W pierwszej kolejności zostały zdefiniowane kryteria jakościowe do oceny efektywności pracy opracowanych metod oraz przedstawiono model symulacyjny, który został użyty do badań. W kolejnych trzech rozdziałach szczegółowo opisano trzy oryginalne asynchroniczne metody radiolokalizacyjne w różnych wariantach. Przeprowadzono analizę matematyczną tych metod oraz na podstawie opracowanego pakietu symulacyjnego wykonano kompleksowe badania efektywności pracy tych metod. Dla każdej metody opracowano również algorytmy estymacji położenia obiektów, a także oszacowano nakład przetwarzania tych algorytmów. Na zakończenie zaproponowano rozwinięcie metody asynchronicznej ATDoA o kompensację współczynników dryftu zegarów stacji referencyjnych. Monografię uzupełnia wydruk kodów źródłowych głównych funkcji pakietu symulacyjnego opracowanego w środowisku MATLAB, które były odpowiedzialne za estymację położenia obiektu za pomocą zadanego algorytmu.
At the Limits of Criticality-Based Quantum Metrology: Apparent Super-Heisenberg Scaling Revisited
- Marek Rams
- Piotr Sierant
- Omyoti Dutta
- Paweł Horodecki
- Jakub Zakrzewski
2018 Pełny tekst Physical Review X
We address the question of whether the super-Heisenberg scaling for quantum estimation is indeed realizable. We unify the results of two approaches. In the first one, the original system is compared with its copy rotated by the parameter-dependent dynamics. If the parameter is coupled to the one-body part of the Hamiltonian, the precision of its estimation is known to scale at most as N−1 (Heisenberg scaling) in terms of the number of elementary subsystems used N. The second approach compares the overlap between the ground states of the parameter-dependent Hamiltonian in critical systems, often leading to an apparent super-Heisenberg scaling. However, we point out that if one takes into account the scaling of time needed to perform the necessary operations, i.e., ensuring adiabaticity of the evolution, the Heisenberg limit given by the rotation scenario is recovered. We illustrate the general theory on a ferromagnetic Heisenberg spin chain example and show that it exhibits such super-Heisenberg scaling of ground-state fidelity around the critical value of the parameter (magnetic field) governing the one-body part of the Hamiltonian. Even an elementary estimator represented by a single-site magnetization already outperforms the Heisenberg behavior providing the N−1.5 scaling. In this case, Fisher information sets the ultimate scaling as N−1.75, which can be saturated by measuring magnetization on all sites simultaneously. We discuss universal scaling predictions of the estimation precision offered by such observables, both at zero and finite temperatures, and support them with numerical simulations in the model. We provide an experimental proposal of realization of the considered model via mapping the system to ultracold bosons in a periodically shaken optical lattice. We explicitly derive that the Heisenberg limit is recovered when the time needed for preparation of quantum states involved is taken into account.
Atmospheric opacity estimation based on IWV derived from GNSS observations for VLBI applications
- Grzegorz Nykiel
- Pawel Wolak
- Mariusz Figurski
2018 Pełny tekst GPS SOLUTIONS
Thermal emission of atmospheric water vapor has a great influence on the calibration of radio astronomical observations at millimeter wavelengths. The phenomenon of an atmospheric water vapor emits noise signal and attenuates astronomical emission. At 22 GHz, integrated water vapor (IWV) obtained from global navigation satellite systems (GNSS) is strictly related to atmospheric opacity (τ0), which is a crucial parameter for data calibration. Therefore, providing highly precise and accurate IWV from GNSS measurements may be an alternative for microwave radiometers. Whereas it is not possible to estimate IWV directly from GNSS measurements, its value is strictly correlated with the zenith wet delay (ZWD) that is estimated together with the coordinates during the GNSS positioning. In this study, differential and Precise Point Positioning methods for ZWD estimation are tested using two different tropospheric mapping functions: Vienna mapping function (VMF) and global mapping function (GMF). After positioning, the IWV conversion is performed using meteorological parameters derived from a meteorological station located near a GNSS site. Analyses for a 3-month period from June 1 to August 30, 2016, were conducted. Based on these, we obtained a very high correlation between IWV and τ0 as measured by the Torun 32 m radio telescope, which amounts about 0.95, for both PPP and differential solutions. Thus, techniques can be successfully used to estimate IWV and calculate τ0. However, the linear regression coefficients depend on the used positioning method.
AUDIO SIGNAL EQUALIZATION BASED ON IMPULSE RESPONSE OF A LISTENING ROOM AND MUSIC CONTENT REPRODUCED
- Piotr Hoffmann
- Bożena Kostek
2018 Zeszyty Naukowe Wydziału ETI Politechniki Gdańskiej. Technologie Informacyjne
A research study presents investigations of the influence of the room acoustics on the frequency characteristic of the audio signal playback. First, a concept of a novel spectral equalization method of the room acoustic conditions is introduced. On the basis of the room spectral response, a system for room acoustics compensation based on an equalizer designed is proposed. The system settings depend on music genre recognized automatically. In order to acquire room acoustic characteristics, a series of measurements are performed. The impact of the impulse response on particular genres of music has also been presented. In the analysis of impulse responses, both examples of concert halls, as well as other acoustic spaces were examined. Also, future work on sound correction has been presented.
Audio-visual aspect of the Lombard effect and comparison with recordings depicting emotional states.
- Szymon Zaporowski
- Bożena Kostek
- Joanna Gołębiewska
- Julia Piltz
2018
In this paper an analysis of audio-visual recordings of the Lombard effect is shown. First, audio signal is analyzed indicating the presence of this phenomenon in the recorded sessions. The principal aim, however, was to discuss problems related to extracting differences caused by the Lombard effect, present in the video , i.e. visible as tension and work of facial muscles aligned to an increase in the intensity of the articulated speech signal. Also the database of recordings, available on the internet, depicting emotional states was analyzed in order to compare and find a visual similarity between the Lombard effect and sentiment contained in speech. The results presented are discussed and further plans are depicted.
Au–Si plasmonic platforms: synthesis, structure and FDTD simulations
- Anna Gapska
- Marcin Stanisław Łapiński
- Paweł Syty
- Wojciech Sadowski
- Józef Eugeniusz Sienkiewicz
- Barbara Kościelska
2018 Pełny tekst Beilstein Journal of Nanotechnology
Plasmonic platforms based on Au nanostructures have been successfully synthesized by directional solidification of a eutectic from Au and the substrate. In order to determine homogeneous shape and space distribution, the influence of annealing conditions and the initial thickness of the Au film on the nanostructures was analyzed. For the surface morphology studies, SEM and AFM measurements were performed. The structure of platforms was investigated using XRD and XPS methods. Structural investigations confirmed, that nanostructures consist of metallic Au, growing along the [111] direction. The most homogeneous seems to be the platform obtained by solidification of a 2.8 nm Au film, annealed at 550 °C for 15 min. This sample was subsequently chosen for theoretical calculations. Simulations of electromagnetic field propagation through the produced samples were performed using the finite-difference time domain (FDTD) method. The calculated absorbance, as a result of the FDTD simulation shows a quite good agreement with experimental data obtained in the UV–vis range.
Automatic Clustering of EEG-Based Data Associated with Brain Activity
- Adam Kurowski
- Katarzyna Elżbieta Mrozik
- Bożena Kostek
- Andrzej Czyżewski
2018
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. Next, the parameterization process is performed in two ways, i.e. by applying Discrete Wavelet Transform and utilizing an autoencoder network. The resulting sets of parameters are then used for the data clustering and the effectiveness of correct assignment of data into adequate clusters is checked. It occurs that the performance of wavelets- and autoencoders-based parametrization is similar, however in several cases, autoencoders allowed for obtaining a higher mean distance and lower standard deviation than distances provided by the wavelet-based method. Moreover, a supervised classification of signals is performed as a form of benchmarking.
Automatic Detection and Monitoring of Cyanobacterial Blooms in the Context of the Marine Cadastre
- Agnieszka Dawidowicz
- Marcin Kulawiak
- Krzysztof Bruniecki
- Marek Ogryzek
2018
In the wake of the European and global spatial data infrastructures (SDI) it is important to build information systems which use and serve thematic data in compliance with the INSPIRE Directive. In the context of hydrographic data, the Directive requires EU member states to collect and share information on maritime areas divided into regions and sub-regions, as well as coastal zone management areas. These data are part of recently developed marine cadastres. According to the INSPIRE Directive the marine cadastres should be supplemented with information on the physical condition of the seas as well as on the specific natural characteristics and phenomena occurring in the seas. The latter can include dynamic information on marine pollution such as cyanobacterial blooms. The paper presents the concept of dynamic satellite-based cyanobacteria bloom detection for the purpose of its analysis in the context of marine cadastre.
Automatic music genre classification based on musical instrument track separation / Automatyczna klasyfikacja gatunku muzycznego wykorzystująca algorytm separacji dźwięku instrumentó muzycznych
- A. Rosner
- Bożena Kostek
2018 Pełny tekst JOURNAL OF INTELLIGENT INFORMATION SYSTEMS
The aim of this article is to investigate whether separating music tracks at the pre-processing phase and extending feature vector by parameters related to the specific musical instruments that are characteristic for the given musical genre allow for efficient automatic musical genre classification in case of database containing thousands of music excerpts and a dozen of genres. Results of extensive experiments show that the approach proposed for music genre classification is promising. Overall, conglomerating parameters derived from both an original audio and a mixture of separated tracks improve classification effectiveness measures, demonstrating that the proposed feature vector and the Support Vector Machine (SVM) with Co-training mechanism are applicable to a large dataset.
Automatic Reduction-Order Selection for Finite-Element Macromodels
- Grzegorz Fotyga
- Krzysztof Nyka
- Michał Mrozowski
2018 IEEE MICROWAVE AND WIRELESS COMPONENTS LETTERS
An automatic reduction-order selection algorithm for macromodels in finite-element analysis is presented. The algorithm is based on a goal-oriented a posteriori error estimator that operates on low-order reduced blocks of matrices, and hence, it can be evaluated extremely quickly.
Automatic system for optical parameters measurements of biological tissues
- Paulina Listewnik
- Adam Mazikowski
2018 Pełny tekst Photonics Letters of Poland
In this paper a system allowing execution of automatic measurements of optical parameters of scattering materials in an efficient and accurate manner is proposed and described. The system is designed especially for measurements of biological tissues including phantoms, which closely imitate optical characteristics of real tissue. The system has modular construction and is based on the ISEL system, luminance and color meter and a computer with worked out dedicated software and user interface. Performed measurements of scattering distribution characteristics for selected materials revealed good accuracy, confirmed by comparative measurements using well-known reference characteristics.
Automatic Watercraft Recognition and Identification on Water Areas Covered by Video Monitoring as Extension for Sea and River Traffic Supervision Systems
- Natalia Wawrzyniak
- Andrzej Stateczny
2018 Polish Maritime Research
The article presents the watercraft recognition and identification system as an extension for the presently used visual water area monitoring systems, such as VTS (Vessel Traffic Service) or RIS (River Information Service). The watercraft identification systems (AIS - Automatic Identification Systems) which are presently used in both sea and inland navigation require purchase and installation of relatively expensive transceivers on ships, the presence of which is not formally required as equipment of unconventional watercrafts, such as yachts, motor boats, and other pleasure crafts. These watercrafts may pose navigation or even terrorist threat, can be the object of interest of the customs, or simply cause traffic problems on restricted water areas. The article proposes extending the traffic supervision system by a module which will identify unconventional crafts based on video monitoring. Recognition and identification will be possible through the use of image identification and processing methods based on artificial intelligence algorithms, among other tools. The system will be implemented as independent service making use of the potential of SOA (Service Oriented Architecture) and XML/SOAP (Extensible Markup Language/Simple Object Access Protocol) technology.
Automatyzacja procesu rehabilitacji dzieci z paralysis cerebralis infantium oraz osteogenesis imperfecta
- Aleksander Pałkowski
2018 Pełny tekst
Celem prac badawczych będących tematem dysertacji jest opracowanie podstaw metodologicznych dla automatycznej platformy eksperckiej asystującej podczas procesu rehabilitacji dzieci chorych na paralysis cerebralis infantium oraz osteogenesis imperfecta. Przedstawione cele rozprawy do realizacji wymagały podejścia wieloetapowego, w którym wykonano szereg prac związanych m.in. z: gromadzeniem odpowiednich danych, selekcją efektywnych metod przetwarzania sygnałów, wyborem reprezentacji danych dla maszyn uczących, a także opracowaniem modeli klasyfikacyjnych i regresyjnych. Do utworzenia modeli klasyfikacji i regresji wykorzystano cztery metody uczenia maszynowego: algorytm k najbliższych sąsiadów, drzewa decyzyjne, maszynę wektorów nośnych i perceptron wielowarstwowy. Zbadano ich skuteczność podczas trzech głównych zadań: identyfikacji stanu zdrowia, oceny wykonywanych ćwiczeń oraz estymacji wykonywanych ruchów na podstawie sygnałów elektromiografii powierzchniowej. We wszystkich zadaniach uzyskano w pełni satysfakcjonującą dokładność klasyfikacji i regresji. Ostatecznie, stwierdzono, że na podstawie stosowanej metodyki możliwe jest opracowanie zintegrowanego systemu wnioskującego i kontrolującego przebieg rehabilitacji (zautomatyzowanie).
Autonomous Vehicle Navigation in Dense Urban Area in Global Positioning Context
- Jerzy Demkowicz
2018 HUMAN SYSTEMS MANAGEMENT
Autonoumous vehicle services are likely to be adopted in dense urban area. Some research prove that autonomous transport might be capable of improving the transport needs of few times and as a consequence sustainability, congestion and safety may be improved. The world, hopefully is close to a transport revolution age. These studies are perhaps exaggerated, over-optimistic and far fro fully operational. The paper takes into account some aspects of autonomous vehicle navigation in a global context, that means in the context of GNSS and introduce a new approach to a position calculation in the urbanized areas using that global navigational system.
Awarie mostu Cłowego w Szczecinie
- Krzysztof Żółtowski
- Mikołaj Binczyk
2018 Pełny tekst Materiały Budowlane
W artykule przedstawiono historię budowy i eksploatacji mostu Cłowego w Szczecinie. W ciągu 56 lat eksploatacji obiektu wykonano wiele ekspertyz, napraw i remontów. Ostatecznie most został zamknięty z powodu awarii stalowych kabli sprężenia zewnętrznego. Przedstawiono główne przyczyny degradacji obiektu i awarii. Opisano również obliczenia statyczne i wytrzymałościowe wykonane do koncepcji rozbiórki przęseł mostu.
Azerbejdżan w organizacjach międzynarodowych i regionalnych
- Krystyna Gomółka
2018
Artykuł ukazuje role i miejsce Azerbejdżanu w organizacjach międzynarodowych
Azo group(s) in selected macrocyclic compounds
- Ewa Wagner-Wysiecka
- Natalia Łukasik
- Jan Biernat
- Elżbieta Luboch
2018 Pełny tekst Journal of Inclusion Phenomena and Macrocyclic Chemistry
Azobenzene derivatives due to their photo- and electroactive properties are an important group of compounds finding applications in diverse fields. Due to the possibility of controlling the trans–cis isomerization, azo-bearing structures are ideal building blocks for development of e.g. nanomaterials, smart polymers, molecular containers, photoswitches, and sensors. Important role play also macrocyclic compounds well known for their interesting binding properties. In this article selected macrocyclic compounds bearing azo group(s) are comprehensively described. Here, the relationship between compounds’ structure and their properties (as e.g. ability to guest complexation, supramolecular structure formation, switching and motion) is reviewed.