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Repozytorium publikacji
Politechniki Gdańskiej

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Ostatnie pozycje

  • Czujniki optyczne jako narzędzia analityczne do wykrywania i oznaczania jonów
    • Natalia Łukasik
    • Piotr Barczak
    2019 Chemia w Szkole

    Prawidłowe funkcjonowanie organizmu ludzkiego w dużej mierze opiera się na odpowiedniej równowadze jonowej. Jak wykryć i oznaczyć te jony?

  • Czy doświadczenie ma znaczenie? Intencje przedsiębiorcze potencjalnych sukcesorów z perspektywy społeczno-kognitywnej
    • Magdalena Licznerska
    2019

    Pomimo wielu różnorodnych działań mających na celu zachęcanie młodych osób do przedsiębiorczości, wielu z nich nie przejmuje firm rodzinnych, nie zostaje przedsiębiorcami, a znacznej części nie można nawet określić mianem osób przedsiębiorczych. Zrozumienie, co sprawia, że dana osoba staje się przedsiębiorcą, ma kluczowe znaczenie dla rozwoju nowych firm i przetrwania tych z dłuższą tradycją, firm rodzinnych. W związku z tym, że przedsiębiorczość jest zachowaniem intencjonalnym, istnieje potrzeba badania intencji przedsiębiorczych młodych osób, a w kontekście firm rodzinnych, potencjalnych sukcesorów. W niniejszym artykule została wprowadzona i wyjaśniona społeczno – kognitywna teoria kariery (SCCT). Wyjaśniono, dlaczego poprzednie modele analizy intencji przedsiębiorczości mogą być nieodpowiednie i dlaczego spojrzenie z perspektywy SCCT będzie bardziej właściwe do badania procesu formowania intencji przedsiębiorczych. Ujęcie w modelu konceptualnym kontekstu zewnętrznego umożliwia przeanalizowanie wpływu środowiska firmy rodzinnej na intencje przedsiębiorcze potencjalnych sukcesorów. Poczucie przedsiębiorczej samoskuteczności potencjalnych sukcesorów może być konstrukcją wyjaśniającą ich intencje przedsiębiorcze, ale także obok postrzeganych efektów przedsiębiorczych, może być jednym z mediatorów związku pomiędzy pochodzeniem z firmy rodzinnej i intencjami przedsiębiorczymi.

  • Czy fizyka może pomóc w rozwoju sztucznej inteligencji? (Czy sztuczna inteligencja pomoże w rozwoju fizyki?)
    • Beata Bochentyn
    2019 Pełny tekst

    Zaprezentowano możliwości zastosowania metod sztucznej inteligencji w rozwiązywaniu problemów z zakresu fizyki i inżynierii materiałowej

  • Czy ścieki oczyszczone stanowią istotne źródło farmaceutyków w środowisku wodnym?
    • Sylwia Fudala-Książek
    • Małgorzata Szopińska
    • Katarzyna Jankowska
    • Aneta Łuczkiewicz
    2019 Wodociągi Polskie

    Jak dotąd nie zostały jeszcze wprowadzone regulacje prawne dotyczące stopnia redukcji mikrozanieczyszczeń i/lub ich maksymalnych stężeń na odpływie z oczyszczalni. Niemniej jednak zgodnie ze stanowiskiem Komisji Europejskiej i innych organizacji, istnieje potrzeba ich monitoringu oraz dopracowania metod usuwania mikrozanieczyszczeń w celu poprawy jakości wód będących odbiornikiem ścieków oczyszczonych. Dlatego też zachęca się OŚ do wykonywania wstępnych analiz obecności mikrozanieczyszczeń na wejściu i wyjściu z oczyszczalni, oraz w wodach odbiornika w celu uzyskania szerokiej charakterystyki problemu. Nie bez znaczenia są również konsultacje społeczne i wzrost świadomości zagrożeń związanych z obecnością i stałą emisją mikrozanieczyszczeń, w tym farmaceutyków, do środowiska. Podjęcie działań związanych z implementacją zaawansowanych metod oczyszczania ścieków wymaga bowiem nie tylko analizy aspektów technologicznych ale również socjoekonomicznych. Wdrożenie w pełnej skali technologii ozonowania, czy adsorpcji na węglu aktywnym spowoduje bowiem wzrost kosztów eksploatacji oczyszczalni ścieków, a tym samym prawdopodobnie również opłat za wodę i ścieki. Z drugiej strony efektem długoterminowym wdrożenia zaawansowanych metod oczyszczania ścieków będzie podniesienia jakości życia mieszkańców oraz stworzenie ekologicznych podstaw do zrównoważonego rozwoju pobliskich środowisk. Jest to również pole do działania dla inżynierów i technologów i poszukiwania nowych, innowacyjnych, wysoce efektywnych technologii, które przy niskich kosztach inwestycyjnych i eksploatacyjnych pozwolą na zapewnienie bezpieczeństwa ekologicznego w przyszłości (np. wykorzystanie nowoczesnych materiałów w procesach elektrodowych). Bania zostały zrealizowane w ramach projektu MORPHEUS - Modelowe obszary usuwania farmaceutyków na południowym Bałtyku, ang. Model Areas for Removal of Pharmaceutical Substances In the South Baltic, realizowanego w ramach Programu Interreg Południowy Bałtyk nr STHB.02.02.00-SE-0038/16. Oznaczenia substancji farmaceutycznych zostały wykonane przez Ola Svahn i Erland Björklund w specjalistycznym laboratorium analitycznym na Uniwersytecie w Kristianstad (https://www.hkr.se).

  • Damage Detection in the Wind Turbine Blade Using Root Mean Square and Experimental Modal Parameters
    • Łukasz Doliński
    • Marek Krawczuk
    • Arkadiusz Żak
    2019

    The paper presents results of an experimental study related to a non-destructive diagnostic technique used for preliminary determination the location and size of delamination in composite coatings of wind turbine blades. The proposed method of damage detection is based on the analysis of the ten first mode shapes of bending vibrations, which correspond to displacements of rotor blades perpendicular to the rotor plane. Modal parameters depend on the physical properties of the structure. On the other hand, failures can affect these properties (e.g. locally reduce the stiffness of the structure). Monitoring of selected modal parameter can allow determination the technical condition of the structure. The main assumption of the presented method is a comprehensive analysis of the measured data by determination the root mean square value (RMS) for each measurement point from all forms of free vibration obtained from the experiment. As a result, information contained in all modes of vibrations that may indicate damage of the blade will be included in a single characteristic. The investigations were carried out on a scaled-down model of a wind turbine blade of a rotor diameter of 36 m. The modal parameters have been determined only experimentally using a Laser Doppler Scanning Vibrometer. Damage was simulated for three localizations by additional high stiffness elements fixed to the surface of the blade. The results of the research presented in this paper confirm the effectiveness of RMS calculation in detection damage using modes of vibrations.

  • DANE I DOKUMENTACJA MEDYCZNA
    • Jacek Rumiński
    2019

    Rozdział analizuje aspekty danych i dokumentacji medycznych z odniesieniu do międzynarodowych norm technicznych takich jak DICOM, HL7. Wskazuje również definicje dokumentacji medycznej związane z polskim prawem. Porusza również aspekty związane z kolekcjami danych (np. biobanki) jak i bezpieczeństwem danych.

  • Data librarian and data steward – new tasks and responsibilities of academic libraries in the context of Open Research Data implementation in Poland
    • Anna Wałek
    2019 Pełny tekst Przegląd Biblioteczny

    Thesis/Objective – The policy of Open Access (OA) for researching resources in Europe has been implemented for more than 10 years. The first recommendations concerning providing OA to scientific materials were defined during the implementation of the 7th Framework Programme. Introducing another set of recommendations concerning OA to research data was the next stage. The recommendations were transformed into obligations under the Horizon 2020 Programme. In 2018, research-funding institutions were associated in the Plan S document issued by CoalitionS ,which aims to ac celerate the transition to full and immediate OA to publications from publicly funded research until January 2021. Academic libraries have always been pioneers in implementing OA to research, creating the necessary tools (platforms and repositories), and preparing training workshops for researchers. OA policy implementation, including both access to research resources and data, is accelerating. That is why the role of academic libraries and academic librarians has become crucial. The article presents how library services and the scope of tasks of their employees change in connection with the introduction of open access policies for research data in Poland. Research methods – A critical review of the literature was used to analyse the content of foreign and Polish LIS literature published in the years 2009-2019. In addition, official documents issued by the European Commission were analysed, as well as websites devoted to Open Research Data (ORD). Results and conclusions – Some new specialisations in librarianship have been introduced – e.g. a data librarian who is responsible not only for academic staff training sessions on Open Research Data, but also for assistance for research teams in the field of data management and data curation. In the future, academic libraries will be responsible for coordinating the work of data stewards responsible for supporting the process of research data creating and managing at university departments and in research teams.

  • Database of speech and facial expressions recorded with optimized face motion capture settings
    • Andrzej Czyżewski
    • Miłosz Kawaler
    2019 Pełny tekst JOURNAL OF INTELLIGENT INFORMATION SYSTEMS

    The broad objective of the present research is the analysis of spoken English employing a multiplicity of modalities. An important stage of this process, discussed in the paper, is creating a database of speech accompanied with facial expressions. Recordings of speakers were made using an advanced system for capturing facial muscle motion. A brief historical outline, current applications, limitations and the ways of capturing face muscle motion as well as the problems with recording facial expressions are discussed. In particular, the scope of the present analysis concerns the registration of facial expressions related to emotions of speakers which accompany articulation. The camera system, instrumentation and software used for registration and for post-production are outlined. An analysis of the registration procedure and the results of the registration process was performed. The obtained results demonstrate how muscle movements can be registered employing reflective markers and point at the advantages and limitations of applying FMC (Face Motion Capture) technology in compiling a multimodal speech database. A short discussion pertaining to the usage of FMC as ground truth data source in facial expression databases concludes the paper.

  • Daylight evaluation for multi-family housing in Poland
    • Natalia Sokół
    2019 Pełny tekst

    This PhD dissertation focuses on methods of daylight appraisal useful in the design of the contemporary multifamily housing. The theoretical part of the thesis offers a review of daylight indicators, evaluations methods and tools within the built environment. It covers a review of daylight recommendations found in building standards and other normative documents affecting the design of the residential spaces. A pilot work survey carried out among 140 architecture students aimed to verify students', perception, preferences on daylight as well as their knowledge about contemporary daylight metrics and assessment methods and regulations. The empirical part of the thesis presents the experiment focused on the appraisal of daylight conditions within 20 rooms spaces via on-site repeated luminance measurements, the questionnaire focusing on inhabitants' perception, preferences and satisfaction with the daylight conditions within their dwellings, and luminance, illuminance simulation. The obtained results are presented in numerical form and graphical notation, in the form of multi-coloured graphs - images. In the summary, the potential and level of difficulty of the presented daylight appraisal methods were assessed. The influence of normative documents on the design solutions affecting propagation of light in the multi-dwelling structures was described. The results confirm that the analysis and assessment of daylight is crucial at all stages of planning residential architecture. A well-thought-out design of daylight affects the perception of residential interiors by their users and impacts their quality of life.

  • DAYLIGHT WITHIN A ROOM IN THE EYES OF ARCHITECTURE STUDENTS
    • Natalia Sokół
    • Giuliani Federica
    • Justyna Martyniuk-Pęczek
    2019

    A questionnaire was conducted to investigate how 140 architecture students apprise daylight conditions within the classrooms. The participants were requested to evaluate the luminous environment and their luminous comfort. They were also asked about light preferences and knowledge on daylight metrics and regulations. The students’ subjective appraisals results were compared with the experts’ assessment and the on-site illuminance measurements. Later on, the students had to carry out a series of daylight indices simulations summarizing daylight conditions in their private rooms (a user’s experience), and in a room, within a building, they had been designing (a designer’s experience). The perception of the luminous environment was analysed against participants’ comprehension of daylight simulations data. The issues students encountered during the daylight indicators analysis suggested that more coherent daylight education should be offered for future architects.

  • Debonding Detection in Reinforced Concrete Beams with the Use of Guided Wave Propagation
    • Beata Zima
    2019

    One of the most frequent damage of the reinforced concrete structures is debonding between steel bar and concrete cover. In the case of debonding occurrence not only the strength of the structure decreases, but also it is more vulnerable to corrosion damages. For this reason fast and effective methods of debonding detection in an early stage of its development need a significant boost. The paper presents analytical and experimental investigation of debonding detection in reinforced concrete beams using non-destructive method based on guided waves propagation. Concrete beams of rectangular cross-section consisting of four steel rebars with pre-existing debonding are investigated. Lack of adhesive connection between one rod and concrete cover is provided by introducing cellophane film of a small thickness (90 μm). The research is focused on detection of debonding with variable length on the basis of time-domain signals captured by piezoelectric sensors. Presented method of damage detection takes advantage of the time of flight of the reflections registered at the ends of the specimens.

  • Decision making process using deep learning
    • Olgun Aydin
    2019

    Endüstri 4.0, dördüncü endüstri devrimi veya Endüstriyel Nesnelerin İnterneti (IIoT) olarak adlandırılan sanayi akımı, işletmelere, daha verimli, daha büyük bir esneklikle, daha güvenli ve daha çevre dostu bir şekilde üretim yapma imkanı sunmaktadır. Nesnelerin İnterneti ile bağlantılı yeni teknoloji ve hizmetler birçok endüstriyel uygulamada devrim niteliği taşımaktadır. Fabrikalardaki otomasyon, tahminleyici bakım (PdM – Predictive Maintenance) modellerigibi gelişmeler işletmelere, iş modellerini değiştiren yenilikçi çözümler sunmaktadır. Günümüz endüstriyel uygulamalarında ihtiyaç duyulan yüksek otomasyon seviyesini sağlamak için, daha verimli ekipman kullanılmalı, daha akıllı sistemler oluşturulmalıdır. Bu sayede, hem üretimdeki verim artacak hem de daha güvenli bir çalışma ortamı da sağlanmış olacaktır. İşletmeler, üretimlerine minimum aksama süresiyle, optimum hızda devam etmek istemektedir. Bu sebeple, üretimde kullanılan, hareketli parçaları olan makinelerin daha verimli kullanılmasını sağlamak için yapılacak bakım planlamaları kritik önem taşımaktadır. Bu konu ile ilgili yaklaşımlardan bir tanesi, ekipmanların durumuna bakılmaksızın bakım süreçlerini sabit aralıklarla gerçekleştirmektir. Bu yöntem planlanması basit bir yöntemdir ancak, zaman zaman ekipmanların arızası gerçekleştikten sonra bakım işleminin gerçekleştirilmesine ya da ekipmanlarda hiç bir problem yokken bakım işleminin gerçekleştirilmesine neden olabilmektedir. Bu da sistemde uzun süreli aksamalar, gereksiz bakım maliyetleri gibi sonuçları doğurmaktadır. Bakım süreçlerine farklı bir yaklaşım olan PdM, makinenin gözlemlenen durumuna bağlı olarak bakım süreçlerinin yönetilmesine olanak kılmaktadır.PdM yaklaşımına yeni bir akış açısı getirmek amacıyla yapılan bu çalışmada yeni bir derin yapay sinir ağı mimarisi önerilmiştir. Bu mimaride bir girdi katmanı bir LSTM katmanı, bırakma (DO) ve ardından yine bir LSTM katmanı, bir gizli katman ve çıktı katmanı bulunmaktadır. Mimaride kullanılan iterasyon sayısı, parti büyüklüğü Genetik Algoritma (GA) kullanılarak, kayıp fonksiyonunu optimize eden optimizasyon algoritması, çıktı katmanında sonra kullanılan aktivasyon fonksiyonu ve DO oranı ızgara araması (GS) kullanılarak belirlenmiştir.

  • Decisional DNA based intelligent knowledge model for flexible manufacturing system
    • Syed Imran Shafiq
    • Edward Szczerbicki
    • Bogdan Trawiński
    • Cesar Sanin
    2019 JOURNAL OF INTELLIGENT & FUZZY SYSTEMS

    Modeling an effective mechanism for design and control strategies for the implementation of a flexible manufacturing system (FMS) has been a challenge. Consequently, to overcome this issue various techniques have applied in the past but most of these models are effective only for some specific situation or an element of FMS. In this study, the knowledge representation technique of Decisional DNA (DDNA) is applied to FMS to develop a generic model to achieve effective scheduling and manufacturing flexibility. Decisional DNA based Virtual Engineering Objects (VEO) are used as communicating media between machines, equipment and works pieces. The concept of Virtual Engineering Process (VEP) is applied for modeling routing flexibility. VEOs combined with VEPs form FMS-DDNA model, which facilitates in enhancing the performance of FMS, by inducing intelligence based on its own previous experience thus making it practical and smart.

  • Decisional-DNA Based Smart Production Performance Analysis Model
    • Syed Imran
    • Edward Szczerbicki
    • Cesar Sanin
    2019 Pełny tekst CYBERNETICS AND SYSTEMS

    n order to allocate resources effectively according to the production plan and to reduce disturbances, a framework for smart production performance analysis is proposed in this article. Decisional DNA based knowledge models of engineering objects, processes and factory are developed within the proposed framework. These models are the virtual representation of manufacturing resources, and with help of Internet of Things, are capable of capturing the past experience and formal decisions. A case study for the smart tool performance analysis is presented in which information of key tool parameters like tool life, surface integrity, tool forces and chip formation can be sensed in real-time, and predictions can be made according to specific requirements. This framework is capable of creating a cyber-physical conjoining of the bottom-level manufacturing resources and thus can work as a technological basis for smart factories and Industry 4.0.

  • Decontaminating Arbitrary Graphs by Mobile Agents: a Survey
    • Dorota Osula
    2019 UTILITAS MATHEMATICA

    A team of mobile agents starting from homebases need to visit and clean all nodes of the network. The goal is to find a strategy, which would be optimal in the sense of the number of needed entities, the number of moves performed by them or the completion time of the strategy. Currently, the field of distributed graph searching by a team of mobile agents is rapidly expanding and many new approaches and models are being presented in order to better describe real life problems like decontaminating danger areas by a group of robots or cleaning networks from viruses. A centralized searching, when a topology of a graph is known in advance is well studied. This survey presents comprehensive results focusing mainly on an issue of the distributed monotone contiguous decontamination problem, including recent results for clearing graphs with and without a priori knowledge about its topology. We introduce a bibliography for various models, which differ on e.g., knowledge about a graph, properties of agents, time clock or size of the available memory.

  • Decyzje przedsiębiorstwa na rynku finansowym
    • Gabriela Golawska-Witkowska
    • Ewa Mazurek-Krasodomska
    • Anna Rzeczycka
    2019

    Prowadzenie działalności gospodarczej, w tym realizowanie zamierzeń rozwojowych oraz bieżących, wiąże się z ryzykiem niezrealizowania wytyczonego celu. Oznacza to, że firma działa w warunkach ryzyka, a niekiedy niepewności. Główne ryzyka dotyczą utrudnień w pozyskaniu niezbędnych środków finansowych, wahań kursów walut, zmian stóp procentowych itp. Przedsiębiorstwo musi więc znaleźć miejsce, w którym firma pozyska niezbędne kapitały – własne i obce – oraz ograniczy generowane ryzyko. Może to zrobić na rynku finansowym, na określonych jego segmentach, w zależności od potrzeb. Niniejsza publikacja została poświęcona problematyce decyzji przedsiębiorstwa związanych z realizacją wytyczonych celów w kontekście pozyskiwania źródeł finansowania oraz minimalizowania ryzyka. Główne założenia pracy obejmują wskazanie zasad podejmowania przez przedsiębiorstwo decyzji na rynku finansowym oraz określenie miejsca instrumentów tego rynku w bilansach polskich przedsiębiorstw. Monografia przeznaczona jest dla studentów kierunków ekonomicznych, w szczególności studiujących zarządzanie finansami przedsiębiorstwa i pragnących poszerzyć wiedzę dotyczącą decyzji podejmowanych przez firmy na rynku finansowym.

  • DEDUKCJA ZACHOWAŃ WĘZŁÓW TRANZYTOWYCH W WIELOSKOKOWEJ SIECI BEZPRZEWODOWEJ W OBECNOŚCI ZAKŁÓCEŃ
    • Jerzy Konorski
    • Karol Rydzewski
    2019 Pełny tekst Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

    Przedstawiono nowy algorytm dedukcji zachowań (metryki reputacji) węzłów tranzytowych w wieloskokowej sieci bezprzewodowej na podstawie potwierdzeń końcowych. Algorytm stosuje znane metody matematyczne i jest odporny na zakłócenia naturalnie występujące w sieciach bezprzewodowych oraz intencjonalne zmiany zachowania węzłów. Informacja zwracana przez algorytm, poza wydedukowanym zachowaniem węzłów, zawiera dane o możliwym błędzie dedukcji.

  • Deep eutectic solvents based highly efficient extractive desulfurization of fuels – Eco-friendly approach
    • Patrycja Makoś
    • Grzegorz Boczkaj
    2019 Pełny tekst JOURNAL OF MOLECULAR LIQUIDS

    The developed process is based on alternative, green and cheap solvents for efficient desulfurization of fuels. Several deep eutectic solvents (DESs) were successfully synthesized and studied as extraction solvents for desulfurization of model fuel containing thiophene (T), benzothiophene (BT) and dibenzothiophene (DBT). The most important extraction parameters (i.e. kind of DES, DES: fuel volume ratio, hydrogen bond acceptor: hydrogen bond donor mole ratio, time of extraction and temperature) were optimized using central composite design model. Furthermore, the mutual solubility of DES and model fuel and influence of multistage extraction, reusability, regeneration of DES and content of aromatic groups in fuel are discussed followed by explanation of desulfurization mechanism, by means of density functional theory (DFT) as well as FT-IR analysis. The studies revealed high desulfurization effectiveness resulting in 91.5%, 95.4% and 99.2% removal of T, BT and DBT respectively in a single stage extraction. A three stage desulfurization provide >99.99% removal of T, BT and DBT. The research on the desulfurization mechanism revealed that π-π interaction is the main driving force for desulfurization process based on DES.

  • Deep learning in the fog
    • Andrzej Sobecki
    • Julian Szymański
    • David Gil
    • Higinio Mora
    2019 Pełny tekst International Journal of Distributed Sensor Networks

    In the era of a ubiquitous Internet of Things and fast artificial intelligence advance, especially thanks to deep learning networks and hardware acceleration, we face rapid growth of highly decentralized and intelligent solutions that offer functionality of data processing closer to the end user. Internet of Things usually produces a huge amount of data that to be effectively analyzed, especially with neural networks, demands high computing capabilities. Processing all the data in the cloud may not be sufficient in cases when we need privacy and low latency, and when we have limited Internet bandwidth, or it is simply too expensive. It poses a challenge for creating a new generation of fog computing that supports artificial intelligence and selects the architecture appropriate for an intelligent solution. In this article, we show from four perspectives, namely, hardware, software libraries, platforms, and current applications, the landscape of components used for developing intelligent Internet of Things solutions located near where the data are generated. This way, we pinpoint the odds and risks of artificial intelligence fog computing and help in the process of selecting suitable architecture and components that will satisfy all requirements defined by the complex Internet of Things systems.

  • Deep Learning Optimization for Edge Devices: Analysis of Training Quantization Parameters
    • Alicja Kwaśniewska
    • Maciej Szankin
    • Mateusz Ozga
    • Jason Wolfe
    • Arun Das
    • Adam Zajac
    • Jacek Rumiński
    • Paul Rad
    2019 Pełny tekst

    This paper focuses on convolution neural network quantization problem. The quantization has a distinct stage of data conversion from floating-point into integer-point numbers. In general, the process of quantization is associated with the reduction of the matrix dimension via limited precision of the numbers. However, the training and inference stages of deep learning neural network are limited by the space of the memory and a variety of factors including programming complexity and even reliability of the system. On the whole the process of quantization becomes more and more popular due to significant impact on performance and minimal accuracy loss. Various techniques for networks quantization have been already proposed, including quantization aware training and integer arithmetic-only inference. Yet, a detailed comparison of various quantization configurations, combining all proposed methods haven’t been presented yet. This comparison is important to understand selection of quantization hyperparameters during training to optimize networks for inference while preserving their robustness. In this work, we perform in-depth analysis of parameters in the quantization aware training, the process of simulating precision loss in the forward pass by quantizing and dequantizing tensors. Specifically, we modify rounding modes, input preprocessing, output data signedness, bitwidth of the quantization and locations of precision loss simulation to evaluate how they affect accuracy of deep neural network aimed at performing efficient calculations on resource-constrained devices.

  • Deep Learning-Based LOS and NLOS Identification in Wireless Body Area Networks
    • Krzysztof Cwalina
    • Piotr Rajchowski
    • Olga Błaszkiewicz
    • Alicja Olejniczak
    • Jarosław Sadowski
    2019 Pełny tekst SENSORS

    In this article, the usage of deep learning (DL) in ultra-wideband (UWB) Wireless Body Area Networks (WBANs) is presented. The developed approach, using channel impulse response, allows higher efficiency in identifying the direct visibility conditions between nodes in off-body communication with comparison to the methods described in the literature. The effectiveness of the proposed deep feedforward neural network was checked on the basis of the measurement data for dynamic scenarios in an indoor environment. The obtained results clearly prove the validity of the proposed DL approach in the UWB WBANs and high (over 98.6% for most cases) efficiency for LOS and NLOS conditions classification.

  • Deep neural network architecture search using network morphism
    • Arkadiusz Kwasigroch
    • Michał Grochowski
    • Mateusz Mikołajczyk
    2019

    The paper presents the results of the research on neural architecture search (NAS) algorithm. We utilized the hill climbing algorithm to search for well-performing structures of deep convolutional neural network. Moreover, we used the function preserving transformations which enabled the effective operation of the algorithm in a short period of time. The network obtained with the advantage of NAS was validated on skin lesion classification problem. We compared the parameters and performance of the automatically generated neural structure with the architectures selected manually, reported by the authors in previous papers. The obtained structure achieved comparable results to hand-designed networks, but with much fewer parameters then manually crafted architectures.

  • Deep neural networks for human pose estimation from a very low resolution depth image
    • Piotr Szczuko
    2019 Pełny tekst MULTIMEDIA TOOLS AND APPLICATIONS

    The work presented in the paper is dedicated to determining and evaluating the most efficient neural network architecture applied as a multiple regression network localizing human body joints in 3D space based on a single low resolution depth image. The main challenge was to deal with a noisy and coarse representation of the human body, as observed by a depth sensor from a large distance, and to achieve high localization precision. The regression network was expected to reason about relations of body parts based on depth image, and to extract locations of joints, and provide coordinates defining the body pose. The method involved creation of a dataset with 200,000 realistic depth images of a 3D body model, then training and testing numerous architectures including feedforward multilayer perceptron network and deep convolutional neural networks. The results of training and evaluation are included and discussed. The most accurate DNN network was further trained and evaluated on an augmented depth images dataset. The achieved accuracy was similar to a reference Kinect algorithm results, with a great benefit of fast processing speed and significantly lower requirements on sensor resolution, as it used 100 times less pixels than Kinect depth sensor. The method was robust against sensor noise, allowing imprecision of depth measurements. Finally, our results were compared with VGG, MobileNet, and ResNet architectures.

  • Degradable poly(ester-ether) urethanes of improved surface calcium deposition developed as novel biomaterials
    • Justyna Kucińska-Lipka
    • Alicja Lewandowska
    • Paweł Szarlej
    • Marcin Stanisław Łapiński
    • Iga Gubańska
    2019 JOURNAL OF BIOACTIVE AND COMPATIBLE POLYMERS

    Bones, which are considered as hard tissues, work as scaffold for human body. They provide physical support for muscles and protect intestinal organs. Percentage of hard tissues in human body depends on age, weight, and gender. Human skeleton consists of 206 connected bones. Therefore, it is natural that the hard-tissue damage such as fractures, osteoporosis, and congenital lack of bone may appear. The innovative way of bone healing is an application of so-called tissue scaffolds. There are many synthetic polymers used in this field, but polyurethanes play a great role in this field. It is due to the possibility to control their degradation rate and to tune their surface to improve the calcification process, required for proper bone regeneration. In this article, we described the fabrication of degradable poly(ester-ether)urethane materials, having different hard-segment content (28% or 47%). PEEURs-28HS and PEEURs-47HS materials were obtained by two-step polymerization method and characterized by mechanical properties, ability to undergo oxidative degradation and surface calcification. Performed studies indicated that the PEEURs-28HS material possessed suitable properties to be proposed as a material for possible application in the bone tissue engineering.

  • Degree product formula in the case of a finite group action
    • Piotr Bartłomiejczyk
    • Bartosz Kamedulski
    • Piotr Nowak-Przygodzki
    2019 Pełny tekst New York Journal of Mathematics

    Let V, W be finite dimensional orthogonal representations of a finite group G. The equivariant degree with values in the Burnside ring of G has been studied extensively by many authors. We present a short proof of the degree product formula for local equivariant maps on V and W.

  • Denitrifcation rate in the mainstream deammonification
    • Anna Wilińska
    • Krzysztof Czerwionka
    2019 Pełny tekst World Scientific News

    The conventional processes of biological nitrogen removal based on nitrification and denitrification does not fit properly into the concept of the circular economy. As the alternative one should consider the deammonification process, which is a combination of partial nitrification (nitritation) and Anammox processes. It consists of removing ammonium nitrogen from wastewater under anaerobic conditions by a group of autotrophic microorganisms. The result is a significant reduction in oxygen demand, while there is no a need for organic compounds that can be converted into biogas in digesters. The deammonification process can be successfully used to treat leachate from the sludge management of WWTP. Currently, research works focus on the use of this process for wastewater treatment in the mainstream of WWTP. This type of research, on a pilot scale, was also carried out at Gdańsk WWTPs. The aim of the presented research was the analysis of the possibility of a simultaneous removal of nitrates, generated during the mentioned deammonification process. The dissolved organic compounds present in the mechanically and chemically treated wastewater can be used in the denitrification process. The efficiency of the process has been determined by performing conventional denitrification rate tests (NUR). The average values of NUR 1 (2.75 mg NOx / gvss ∙ h) and NUR 2 (1.05 NOx / gvss ∙ h) were close to the values typical for mechanically treated municipal sewage. It has been shown that the denitrification process can cause an increase of total nitrogen removal efficiency in the process of deammonification of municipal wastewater. The amount of available organic compounds was sufficient to carry out the denitrification process of nitrates produced during the deammonification process.

  • Density, sound velocity, viscosity, and refractive index of new morpholinium ionic liquids with amino acid-based anions: Effect of temperature, alkyl chain length, and anion
    • Łukasz Marcinkowski
    • Emil Szepiński
    • Maria Jolanta Milewska
    • Adam Kloskowski
    2019 JOURNAL OF MOLECULAR LIQUIDS

    In this work, room temperature synthesis of twenty new ionic liquids (ILs) based on the N-alkyl-N-methylmorpholinium ([Mor1,R], R = 2, 3, 4, 6, 8) cation and N-acetyl-L-amino acid anions (L-alaninate, L-valinate, L-leucinate, L-isoleucinate) was described. The synthesized ILs were characterized by various spectroscopic techniques and high-resolution mass spectrometry. Furthermore, density (ρ), sound velocity (v), viscosity (η) and refractive index (nD) have been measured within the temperature range of T = (298.15 to 318.15) K and at 0.1 MPa pressure. The density, sound velocity and viscosity values were fitted to linear and Vogel–Tammann–Fulcher (VTF) equation. Moreover, on the basis of the refractive index values, molar refraction (Rm) and free volume (Vf) were calculated using the Lorentz–Lorenz equation. The thermodynamic properties such as thermal expansion coefficient (α) and isentropic compressibility (κS) were calculated using the experimental values of density and sound velocity. Finally, the obtained data were evaluated in order to determine the effect of such parameters as temperature, the nature of the anion and the length of the cation alkyl chain.

  • Deposition and Electrical and Structural Properties of La0.6Sr0.4CoO3 Thin Films for Application in High-Temperature Electrochemical Cells
    • Bartosz Kamecki
    • Jakub Karczewski
    • Hamid Abdoli
    • Ming Chen
    • Grzegorz Jasiński
    • Piotr Jasiński
    • Sebastian Molin
    2019 Pełny tekst JOURNAL OF ELECTRONIC MATERIALS

    Low-temperature deposition of electroceramic thin films allows the construction of new devices and their integration with existing large-scale fabrication methods. Developing a suitable low-cost deposition method is important to further advance the development of microdevices. In this work, we deposited a 1-lm-thick La0.6Sr0.4CoO3d (LSC) perovskite with high electrical conductivity on sapphire substrates at 400C and analyzed its electrical, morphological and structural properties as a function of temperature in the range of 400– 1100C. The results show that spray pyrolysis can be used to deposit highquality reproducible layers with the desired chemical and phase composition. Upon heating to around 600C, the residual C–O and C=O species are removed, and the deposited layers crystallize and become conducting. The dependence of electrical conductivity versus processing temperature has a complex character—the maximum conductivity is found for layers processed at 800C. An analytical model of stress distribution was used to predict stress to which the bi-layer material would be exposed to while being cooled down from the annealing temperature to room temperature. The high electronic conductivity and high-quality microstructure of the LSC layers, which can be adjusted with the appropriate heat treatment procedure, make them suitable for applications in electrochemical devices applied in integrated energy modules, including electrodes or contacts.

  • Derecho Evolving from a Mesocyclone—A Study of 11 August 2017 Severe Weather Outbreak in Poland: Event Analysis and High-Resolution Simulation
    • Mateusz Taszarek
    • Natalia Piguj
    • Juliusz Orlikowski
    • Artur Surowiecki
    • Szymon Walczakiewicz
    • Wojciech Pilorz
    • Krzysztof Piasecki
    • Łukasz Pajurek
    • Marek Półrolniczak
    2019 Pełny tekst MONTHLY WEATHER REVIEW

    This study documents atmospheric conditions, development, and evolution of a severe weather outbreak that occurred on 11 August 2017 in Poland. The emphasis is on analyzing system morphology and highlighting the importance of a mesovortex in producing the most significant wind damages. A derecho-producing mesoscale convective system (MCS) had a remarkable intensity and was one of the most impactful convective storms in the history of Poland. It destroyed and partially damaged 79 700 ha of forest (9.8 million m3 of wood), 6 people lost their lives, and 58 were injured. The MCS developed in an environment of high 0–3-km wind shear (20–25 m s−1), strong 0–3-km storm relative helicity (200–600 m2 s−2), moderate most-unstable convective available potential energy (1000–2500 J kg−1), and high precipitable water (40–46 mm). Within the support of a midtropospheric jet, the MCS moved northeast with a simultaneous northeastward inflow of warm and very moist air, which contributed to strong downdrafts. A mesocyclone embedded in the convective line induced the rear inflow jet (RIJ) to descend and develop a bow echo. In the mature stage, a supercell evolved into a bookend vortex and later into a mesoscale convective vortex. Swaths of the most significant wind damage followed the aforementioned vortex features. A high-resolution simulation performed with initial conditions derived from GFS and ECMWF global models predicted the possibility of a linear MCS with widespread damaging wind gusts and embedded supercells. Simulations highlighted the importance of cloud cover in the preconvective environment, which influenced the placement and propagation of the resulting MCS.

  • Derivation of motor mean phase currents in PMSM drives operating with low switching-to-fundamental frequency ratio
    • Leszek Jarzębowicz
    2019 Pełny tekst Power Electronics and Drives

    Pulse width modulation (PWM) of inverter output voltage causes the waveforms of motor phase cur-rents to consist of distinctive ripples. In order to provide suitable feedback for the motor current con-trollers, the mean value must be extracted from the currents’ waveforms in every PWM cycle. A com-mon solution to derive the mean phase currents is to sample their value at the midpoint of a symmetrical PWM cycle. Using an assumption of linear current changes in steady PWM subintervals, this midpoint sample corresponds to the mean current in the PWM cycle. This way no hardware filtering or high-rate current sampling is required. Nevertheless, the as-sumption of linear current changes has been recently reported as over simplistic in permanent magnet syn-chronous motor (PMSM) drives operating with low switching-to-fundamental frequency ratio (SFFR). This, in turn, causes substantial errors in the repre-sentation of the mean phase currents by the midpoint sample. This paper proposes a solution for deriving mean phase currents in low SFFR PMSM drives, which does not rely on the linear current change as-sumption. The method is based on sampling the cur-rents at the start point of a PWM cycle and correct-ing the sampled value using a model-based formula that reproduces the current waveforms. Effective-ness of the method is verified by simulation for an exemplary setup of high-speed PMSM drive. The re-sults show that the proposed method decreases the error of determining the mean phase currents approx-imately 10 times when compared to the classical midpoint sampling technique.

  • Design and Experiments of a Piezoelectric Motor Using Three Rotating Mode Actuators
    • Roland Ryndzionek
    • Łukasz Sienkiewicz
    • Michał Michna
    • Filip Kutt
    2019 Pełny tekst SENSORS

    This paper represents a numerical and experimental investigation of the multicell piezoelectric motor. The proposed design consists of three individual cells that are integrated into the stator, double rotor, and a preload system combined into a symmetrical structure of the motor. Each of the cells is characterized by a traveling wave and rotating mode motor. A finite element numerical analysis is carried out to obtain optimal geometrical dimensions of the individual cell in terms of generated vibrations and resonant frequencies of the structure. The results of the numerical analysis are compared with analytical calculations based on the equivalent circuit theory. Experimental tests are also presented, including laser interferometry measurements of vibrations generated at the surface of the stator, impedance analysis, as well as measurements of mechanical characteristics of the complete motor. The final stage of the study concludes that the presented motor can provide relatively high torque compared with other traveling wave rotary motors.

  • Design and material selection for a patient transport device in field hospitals
    • Magda Dziaduszewska
    • Martyna Zimna
    • Beata Świeczko-Żurek
    2019 Pełny tekst Minerva Ortopedica E Traumatologica

    ACKGROUND: A major cause of patient and hospital worker injuries occurs transferring patients between two planes. The main aim of this paper was to propose a design of patient’s lift and transfer apparatus for use in field hospitals. The assumption was to design lightweight, durable and ergonomic device using innovative material. The authors concentrated on partial elimination of manual lifting in order to device could work both in two situations: with or without electricity. The paper includes mechanical design, material selection and analytical calculation. METHODS: In order to carry out strength calculations, the shape and size of device was designed using AutoCAD. Based on a comparison of composite material properties, an epoxy-carbon laminate was selected. The strength calculations were performed in the following order: determination of elementary stresses, determination of the most dangerous cross-section, calculation of tensile strength, calculation of Young’s modulus, selection of channel dimensions, determination of material parameters (thickness, fiber mass), determination of substitute stresses. RESULTS: To design a lightweight, durable and ergonomic patient lift with lifting capacity of 150 kg an epoxy-carbon laminate composed of three layers was chosen. A profile in a C-shape and dimension of 138x90x14 mm has been designed. Patient lift includes an arm of 1.6 m height and 1m length of the horizontal beam. The designed transport mechanism uses rollers, a linear electric actuator and a crank with a worm gear. CONCLUSIONS: The designed device fulfil the most important criterion, which is to ensure the safety of patients and medical personnel. The height adjustment mechanism partially eliminates the manual transfer of patients and is adapted to the conditions existing in a field hospital.

  • Design and optimization of a novel compact broadband linearly/circularly polarized wide-slot antenna for WLAN and Wi-MAX applications
    • Ullah Ubaid
    • Sławomir Kozieł
    2019 Pełny tekst RADIOENGINEERING

    A novel topologically modified structure of a compact low profile wide-slot antenna for broadband applications is presented. The antenna comprises a modified E-shaped slot with unequal arm lengths in the ground plane, and a parasitic quasi-rectangular loop placed coplanar with the feedline. For exciting orthogonal modes with equal amplitude, a single-point feeding technique with an asymmetrical geometry of the coplanar waveguide is used to feed the antenna. A multi-stage EM-driven optimization is used to rigorously optimize all the parameters for best impedance bandwidth and axial ratio bandwidth. The total footprint of the antenna is only 0.71 λg^2 and a 41% impedance bandwidth along with 33% axial ratio bandwidth has been achieved which covers several WLAN and WiMAX bands.

  • Design Equation for Stirring Fluid by a Stream Pump in a Circulating Tank
    • Jerzy Sawicki
    • Paweł Wielgat
    • Piotr Zima
    2019 Pełny tekst Water

    A circulating tank is a very useful theoretical scheme for many fluid-flow objects in several branches of engineering. The motion of the fluid in such objects can be induced in different ways. A stream pump provides an especially interesting possibility; however, the quantitative description of such devices shows some shortcomings. Such a device is analogous to a jet pump, thus has similar advantages (simplicity of construction, lack of movable elements, insensibility to pollutants) and disadvantages (low efficiency). On the one hand, from the technical viewpoint, one can make use of technical instructions presented in handbooks and offered by producers, and on the other hand by performing calculations using CFD tools. In this situation, it is self-evident that some intermediary method of design, i.e., formally simple, but physically convincing, would be welcome both by theoreticians and by engineers. Such a method is proposed in this paper and takes the form of an algebraic formula, combining the discharge of the stream pump and the discharge of the circulation induced by this stream. This expression, based on the balance between the power of the stream and the power of dissipation, has been experimentally verified with a positive result.

  • Design of control algorithms for mobile robots in an environment with static and dynamic obstacles
    • Robert Piotrowski
    • Bartosz Maciąg
    • Wojciech Makohoń
    • Krzysztof Milewski
    2019 Pełny tekst Journal of Automation, Mobile Robotics and Intelligent Systems - JAMRIS

    This article proposes the construction of autonomous mobile robots and designing of obstacle avoidance algorithms for them. Nowadays, mobile robots are gaining more and more popularity on the customer as well as industrial market, for example as automatic vacuum cleaners or lawnmowers. Obstacle avoidance algorithms play an important role in performance of this types of robots. The proposed algorithms were designed for builds with rather not expensive electronic components, especially sensors with limited precision and dynamics. The project began with the selection of needed parts and building materials as well as designing of the PCB and assembling the whole construction. The project included also designing and developing the software responsible for, among others, implementation of obstacle avoidance algorithms. After the project’s completion, a series of tests in a closed environment was conducted to verify the quality of vehicles’ performance. Results of tests were positive.

  • Design of dimensionally stable composites using efficient global optimization method
    • Levent Aydin
    • Olgun Aydin
    • H Seçil Artem
    • Ali Mert
    2019 PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART L-JOURNAL OF MATERIALS-DESIGN AND APPLICATIONS

    Dimensionally stable material design is an important issue for space structures such as space laser communication systems, telescopes, and satellites. Suitably designed composite materials for this purpose can meet the functional and structural requirements. In this paper, it is aimed to design the dimensionally stable laminated composites by using efficient global optimization method. For this purpose, the composite plate optimization problems have been solved for high stiffness and low coefficients of thermal and moisture expansion. Some of the results based on efficient global optimization solution have been verified by genetic algorithm, simulated annealing, and generalized pattern search solutions from the previous studies. The proposed optimization algorithm is also validated experimentally. After completing the design and optimization process, failure analysis of the optimized composites has been performed based on Tsai–Hill, Tsai–Wu, Hoffman, and Hashin–Rotem criteria.

  • Design of Jack-up Platform for 6 MW Wind Turbine: Parametric Analysis Based Dimensioning of Platform Legs
    • Paweł Dymarski
    2019 Pełny tekst Polish Maritime Research

    The article presents the results of the research conducted within the framework of the project entitled WIND-TU-PLA (ERA-NET, MARTEC II), the general aim of which was to design and analyse supporting structures for wind turbines intended for operation on the South Baltic area. The research part described in the article aimed at developing a preliminary design for a jack-up platform which can operate on water areas with depth of 40 m. The main task was to determine optimal dimensions of platform legs and the radius of their spacing. Two jack-up platform concepts differing by spacing radius and hull dimensions were designed with the intention to be used as a supporting structure for a 6-MW offshore wind turbine. For each concept, the parametric analysis was performed to determine optimal dimensions of platform legs (diameter Dleg and plating thickness tleg). Relevant calculations were performed to assess the movements of the platform with parameters given in Table 1 in conditions simulating the action of the most violent storm in recent 50 years. The obtained results, having the form of amplitudes of selected physical quantities, are shown in comprehensive charts in Fig. 6 and 7. Based on the critical stress values (corresponding to the yield stress), the area was defined in which the impact strength conditions are satisfied (Fig. 14).Then, the fatigue strength analysis was performed for two selected critical leg nodes (Fig. 12). Its results were used for defining the acceptable area with respect to structure’s fatigue (Fig. 14). Geometric parameters were determined which meet the adopted criteria, Table 6. The decisive criterion turned out to be the fatigue strength criterion, while the yield point criterion appeared to be an inactive constraint.

  • Design of Microwave-Based Angular Displacement Sensor
    • Abhishek Jha
    • Nicolo Delmonte
    • Adam Lamęcki
    • Michał Mrozowski
    • Bozzi Maurizio
    2019 IEEE MICROWAVE AND WIRELESS COMPONENTS LETTERS

    This letter presents a novel microwave-based rotation sensor having a wide dynamic range to detect and measure the angular displacement in terms of the change in resonant frequency. The proposed sensor is based on the microstrip technology, where a rotor comprised of a complementary splitring resonator (CSRR) placed on the ground plane of the microstrip line is free to rotate around its axis. The mechanical rotation of CSRR determines a change in the cross coupling between the microstrip line and the CSRR, thus changing the overall inductance. The proposed planar unloaded microwave sensor, working around ISM band of 5.8 GHz, is quite sensitive to detect angular rotation in the wide dynamic range of 0°–90°. The linearity in dynamic range is achieved in the range of 30°–60°. Operating frequency and bandwidth can be adjusted by loading the rotor with dielectric. Depending on the type of dielectric loading of CSRR, it is possible to select the center frequency from a wide range of 4.67–5.94 GHz, with the bandwidth ranging from 116 to 250 MHz. Due to its features, the proposed sensor can be useful for various industrial applications.

  • Design, synthesis, and molecular docking of new 5-HT reuptake inhibitors based on modified 1,2-dihydrocyclopenta[b] indol-3(4H)-one scaffold
    • Milena Szewczyk
    • Paweł Punda
    • Karolina Janikowska
    • Sławomir Makowiec
    2019 Pełny tekst JOURNAL OF CHEMICAL SCIENCES

    A new group of serotonin reuptake inhibitors containing 1,2-dihydrocyclopenta[b]indol-3(4H)-one scaffoldwas synthesized, starting from indole 5-((1H-indol-3-yl)(1,3-dioxane-4,6-diones as a key intermediates. Following three transformations including intramolecular cyclization and formation of imines, a series of new ligand for human serotonin transporter was obtained. The ability of these ligands to inhibit human TS3 serotonin transporter as well as selectivity toward human D3 dopamine receptor and dopamine transporter were tested in silico using docking software.

  • Detecting coupling directions with transcript mutual information: A comparative study
    • José Amigó
    • Beata Graff
    • Grzegorz Graff
    • Roberto Monetti
    • Katarzyna Tessmer
    2019 DISCRETE AND CONTINUOUS DYNAMICAL SYSTEMS-SERIES B

    Causal relationships are important to understand the dynamics of coupled processes and, moreover, to influence or control the effects by acting on the causes. Among the different approaches to determine cause-effect relationships and, in particular, coupling directions in interacting random or deterministic processes, we focus in this paper on information-theoretic measures. So, we study in the theoretical part the difference between directionality indicators based on transfer entropy as well as on its dimensional reduction via transcripts in algebraic time series representations. In the applications we consider specifically the lowest dimensional case, i.e., 3-dimensional transfer entropy, which is currently one of the most popular causality indicators, and the (2-dimensional) mutual information of transcripts. Needless to say, the lower dimensionality of the transcript-based indicator can make a difference in practice, where datasets are usually small. To compare numerically the performance of both directionality indicators, synthetic data (obtained with random processes) and real world data (in the form of biomedical recordings) are used. As happened in previous related work, we found again that the transcript mutual information performs as good as, and in some cases even better than, the lowest dimensional binned and symbolic transfer entropy, the symbols being ordinal patterns.

  • Detection of debonding in adhesive joints using Lamb wave propagation
    • Magdalena Rucka
    • Erwin Wojtczak
    • Jacek Lachowicz
    2019 Pełny tekst MATEC Web of Conferences

    Adhesively bonded joints are widely used in many branches of industry. Mechanical degradation of this type of connections does not have significant symptoms that can be noticed during visual assessment, so non-destructive testing becomes a very important issue. The paper deals with experimental investigations of adhesively bonded steel plates with different defects. Five samples (an intact one and four with damages in the form of partial debonding) were prepared. The inspection was conducted with the use of guided wave propagation method. Lamb waves were excited at one point of the sample, whereas the out-of-plane velocity signals were recorded in a number of points spread over the area of overlap. The processing of signals consisted of calculations of weighted root mean square (WRMS). The results of the analysis showed that the WRMS maps allow for identification and determination of size and shape of debonding areas.

  • Detection of the First Component of the Received LTE Signal in the OTDoA Method
    • Gadka Paweł
    • Jarosław Sadowski
    • Jacek Stefański
    2019 Pełny tekst WIRELESS COMMUNICATIONS & MOBILE COMPUTING

    In a modern world there is a growing demand for localization services of various kinds. Position estimation can be realized via cellular networks, especially in the currently widely deployed LTE (Long Term Evolution) networks. However, it is not an easy task in harsh propagation conditions which often occur in dense urban environments. Recently, time-methods of terminal localization within the network have been the focus of attention, with the OTDoA (Observed Time Difference of Arrival) method in particular. One of the main factors influencing the accuracy of location estimation in the OTDoA method is the nature of the propagation channel that affects the ease of isolating the signal component travelling from the transmitter to the receiver through the shortest path. To obtain the smallest possible localization error, it is necessary to detect the first received component of the useful signal. This aim could be achieved by using a proper algorithm within the receiver. This paper proposes a new algorithm for effective detecting of the first component of the LTE downlink signal in the multipath environment. In a mobile terminal location estimation process, CSRS (Cell Specific Reference Signal) signals were used instead of dedicated PRS (Positioning Reference Signal) signals. New solution was verified during the measurement campaign in a real LTE network.

  • Detection of the Oocyte Orientation for the ICSI Method Automation
    • Magdalena Mazur-Milecka
    • Emilia Kaczmarczyk
    • Łukasz Wróbel
    • Patryk Przybylski
    • Marika Trudnowska
    • Aleksandra Podwójcik
    • Monika Jagiello
    • Krzysztof Łukaszuk
    • Jacek Rumiński
    2019 Pełny tekst

    Automation or even computer assistance of the popular infertility treatment method: ICSI (Intracytoplasmic Sperm Injection) would speed up the whole process and improve the control of the results. This paper introduces a preliminary research for automatic spermatozoon injection into the oocyte cytoplasm. Here, the method for detection a correct orientation of the polar body of the oocyte is presented. Proposed method uses deep learning U-Net architecture for object segmentation. This solution proved to be universal and had no demand for numerous dataset or high-quality Images.

  • Detection of the Plant Pathogen Pseudomonas Syringae pv. Lachrymans on Antibody-Modified Gold Electrodes by Electrochemical Impedance Spectroscopy
    • Zofia Cebula
    • Sabina Żołędowska
    • Karolina Dziąbowska
    • Marta Skwarecka
    • Natalia Malinowska
    • Wioleta Białobrzeska
    • Elżbieta Czaczyk
    • Katarzyna Siuzdak
    • Mirosław Sawczak
    • Robert Bogdanowicz
    • Dawid Nidzworski
    2019 Pełny tekst SENSORS

    The present work describes an impedimetric immunosensor for Pseudomonas syringae pv. lachrymans (Psl) detection. This pathogen infects many crop species causing considerable yield losses, thus fast and cheap detection method is in high demand. In the assay, the gold disc electrode was modified with 4-aminothiophenol (4-ATP), glutaraldehyde (GA), and anti-Psl antibodies, and free-sites were blocked with bovine serum albumin (BSA). Sensor development was characterized by cyclic voltammetry (CV) and antigen detection by electrochemical impedance spectroscopy (EIS) measurements. Seven analyzed strains of Psl were verified as positive by the reference method (PCR) and this immunoassay, proving sensor specificity. Label-free electrochemical detection was in the linear range 1 × 103–1.2 × 105 CFU/mL (colony-forming unit) with an R2 coefficient of 0.992 and a detection limit (LOD) of 337 CFU/mL. The sensor did not interfere with negative probes like buffers and other bacteria. The assay was proven to be fast (10 min detection) and easy in preparation. The advantage was the simplicity and availability of the verified analyte (whole bacteria) as the method does not require sample pretreatment (e.g., DNA isolation). EIS biosensing technique was chosen as one of the simplest and most sensitive with the least destructive influence on the probes compared to other electrochemical methods.

  • Detekcja warunków LOS i NLOS w środowisku wewnątrz budynkowym przy użyciu algorytmu głębokiego uczenia
    • Alicja Olejniczak
    • Krzysztof Cwalina
    • Piotr Rajchowski
    • Jarosław Sadowski
    2019 Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

    W środowisku wewnątrzbudynkowym występuje wiele czynników negatywnie wpływających na transmitowane sygnały. Niniejszy artykuł przedstawia metodę opartą na koncepcji głębokich sieci neuronowych, służącą do detekcji warunków LOS i NLOS w środowisku wewnątrzbudynkowym. Algorytm opracowany i przetestowany został na podstawie pomiarów sygnałów UWB przeprowadzonych w rzeczywistym środowisku wewnątrzbudynkowym.

  • Determinants of Business Growth Aspirations among Polish Students: An Empirical Analysis
    • Krzysztof Zięba
    • Jakub Golik
    2019

    This paper aims to discuss the concept of growth aspirations and growth intentions, as well as to identify factors that influence growth aspirations expressed by students with regard to their future businesses. On the basis of a literature review potential determinants of growth aspirations have been identified and tested empirically using data obtained from 223 students from the Pomeranian region in Poland. The authors use Binomial Logistic Regression to propose an econometric model with endogenous variable Growth Aspiration. The results of the study show that from the set of chosen variables, surprisingly some turned out to be statistically insignificant i.a. entrepreneurial self-efficacy, entrepreneurial intention or risk propensity. Eventually, four of the variables have been found to influence declared growth aspirations of respondents in a statistically significant way, namely: gender, declared resistance to stress, perception of higher income being one of the most attractive feature of entrepreneurship and belief that prestige also belongs to the most attractive features of entrepreneurship. Research results are limited to students from one university only and as such, they cannot be perceived as representative for the whole country. Nevertheless, the findings of empirical analysis of growth aspirations determinants allow to identify factors that may decide whether entrepreneurial endeavours undertaken in the future will be intended to be high growth businesses. The paper contributes to a better understanding of the difference between growth aspirations and growth intentions. It also shows what factors shape business growth aspirations of students, which may impact the actual growth of their businesses in the future.

  • Determination and identification of organic acids in wine samples. Problems and challenges.
    • Alicia Robles
    • Magdalena Fabjanowicz
    • Tomasz Chmiel
    • Justyna Płotka-Wasylka
    2019 Pełny tekst TRAC-TRENDS IN ANALYTICAL CHEMISTRY

    For long time, organic acids were underestimated. However, during last two decades there is an increasing interest of natural compounds having antioxidant, antimicrobial and anti-inflammatory properties thus organic acids are very preferable. Wine stands as one of the sources of organic acids since they are responsible for its organoleptic and aestethic character. Nevertheless, it is important to not exceed acceptable level of acidity at particular stage of vinification process. Therefore its determination and quantification is of high importance. Given study gathers data regarding current knowledge with respect to organic acids, focusing on their occurrence in different types of food including wines, their properties and effects on the human body, potential correlations between organic acids and other components of wine. Moreover, the comparison of analytical techniques used for the organic acids determination and challenges, considering their process and green assessment is provided.

  • Determination of Antioxidant Activity of Vitamin C by Voltammetric Methods
    • Klaudia Suliborska
    • Monika Baranowska
    • Agnieszka Bartoszek-Pączkowska
    • Wojciech Chrzanowski
    • Jacek Namieśnik
    2019 Pełny tekst Proceedings

    Voltammetric methods—cyclic (CV) and differential pulse voltammetry (DPV) are considered the most appropriate way to evaluate antioxidant activity of redox active compounds. They provide information about both mechanism and kinetics of electrochemical oxidation of antioxidants as well as their physical and chemical properties such as the redox potential or the number of electrons transferred. These methods are helpful for understanding the mechanisms of oxidation or reduction processes of antioxidant compounds. This work presents the electrochemical properties of vitamin C obtained by both CV and DPV methods.

  • Determination of buckling strength of silos composed of corrugated walls and thin-walled-columns using simplified wall segment models
    • Piotr Iwicki
    • Karol Rejowski
    • Andrzej Tejchman-Konarzewski
    2019 THIN-WALLED STRUCTURES

    W artykule przedstawiono wyniki obszernych analiz numerycznych wyboczenia i stateczności metalowych silosów z blachy falistej wzmocnionych cienkościennymi słupami. Wykonano analizy liniowe i nieliniowe. Do obliczeń zaproponowano proste modele segmentów ścian zamiast skomplikowanych modeli całych silosów. Otrzymano bardzo dobrą zgodność wyników numerycznych. Wyniki obliczeń numerycznych porównano dodatkowo z wynikami normowymi.

  • Determination of free tyrosine in equestrian supplements by LC–MS/MS and comparison of its quantity with total free amino acids content in view of doping control
    • Emilia Waraksa
    • Konrad Kowalski
    • Rafał Rola
    • Ewa Kłodzińska
    • Tomasz Bieńkowski
    • Jacek Namieśnik
    2019 MICROCHEMICAL JOURNAL

    The reports on the probable beneficial impact of tyrosine (TYR) supplementation on performance enhancement have contributed to the growth of interest in TYR in equestrian sports field and related industries, such as the manufacture of dietary and nutritional supplements. In this study, the first attempt to the assessment of horses exposure to TYR during nutritional supplementation was demonstrated by quantification of unbound TYR and a total free amino acids (AAs), and subsequent determination of the ratio of TYR to a total free AAs content in equestrian supplement samples. Within the scope of this study, a rapid and sensitive LC–MS/MS-based method for the determination of unbound TYR and a simple spectrophotometric protocol for the quantification of a total free AAs have been developed and validated according to the international guidelines for bioanalytical methods. For sample preparation, an ultrasound-assisted solid-liquid extraction (USLE; for solid samples) and ultrasound-assisted liquid-liquid extraction (ULLE; for liquid samples) have been optimized. The comprehensive approach on the simultaneous assessment of matrix effect, recovery, process efficiency, accuracy, precision, curve factor and internal standard association demonstrated satisfactory validation parameters for LC–MS/MS-based procedure, such as global matrix effect in the range of 89.9–91.9%, good linearity (R2 > 0.9929), limit of detection (0.6 ng/mL) and recovery within 89.2–108.0%. For spectrophotometric method, limit of detection was 1100 ng/mL, recovery ranged from 103.2 to 108.8%, both, intra- and inter-day accuracy was within 89.5–108.7%, and both, intra- and inter-assay precision was below 8.5%. In view of the satisfactory validation parameters obtained for both methods, the procedures can be utilized for routine analysis of dietary and nutritional supplements.