2021 - Repozytorium publikacji - Politechnika Gdańska

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Unity-Gain Zero-Offset CMOS Buffer with Improved Feedforward Path
- Waldemar Jendernalik
- Jacek Jakusz
- Robert Piotr Piotrowski
- Grzegorz Blakiewicz
- Stanisław Szczepański
2021 Pełny tekst Electronics
A voltage unity-gain zero-offset CMOS amplifier with reduced gain error and increased PSRR (power supply rejection ratio) is proposed. The amplifier uses two feed mechanisms, negative feedback and supporting positive feedforward, to achieve low deviation from unit gain over the entire input range. The circuit, designed in a standard 180-nanometer 1.8-voltage CMOS process, is compared with two known buffers of similar topology, also designed in the same process. Simulations show that, with the same supply (1.8 V), power (1.2 mW), load (12 pF), bandwidth (50 MHz), and similar area (600 m2), the proposed buffer achieves the lowest gain error (0.3%) and the highest PSRR (72 dB).
University Students’ Research on Artificial Intelligence and Knowledge Management. A Review and Report of Multi-case Studies
- Mieczysław Owoc
- Paweł Weichbroth
2021 Pełny tekst
Leading technologies are very attractive for students preparing their theses as the completion of their studies. Such an orientation of students connected with professional experiences seems to be a crucial motivator in the research in the management and business areas where these technologies condition the development of professional activities. The goal of the paper is the analysis of students’ thesis topics defended in the last 10 years in business informatics and computer science in two selected universities in Poland. Our study relies on a detailed review and analysis of qualitative data, obtained from a literature review and multi-case-study research. In the case of the artificial intelligence domain, we have identified six areas of research, namely: general AI, machine learning (ML), natural language processing (NLP), artificial neural networks (ANNs), expert systems, and hybrids. In the case of the knowledge management domain, we have recognized eleven areas of research, regarding the following sectors: e-government, technology, space exploration, social media, manufacturing, healthcare, finance, entertainment, education, e-commerce, and business. Future research will be directed toward extending the scope by including other regions and universities as well as identifying and analyzing students’ motivational factors, associated with research projects and higher education.
Uniwersalny Kontroler Radiowy w systemie STRADAR
- Sylwester Kaczmarek
- Mariusz Miszewski
- Marcin Wyczyński
2021 Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne
Opisano praktyczne rozwiązanie uniwersalnego kontrolera radiowego UKR – jednego z podstawowych elementów funkcjonalnych systemu STRADAR – który obsługuje sensory wykorzystywane na granicy morskiej państwa. Jest on także odpowiedzialny za komunikację personelu Straży Granicznej. UKR ma dwie wersje, jedną mobilną – na jednostki pływające, pojazdy lądowe i jednostki latające, drugą stacjonarną – na stałe punkty obserwacyjne rozmieszczone wzdłuż granicy. Urządzenie to uzyskało pozytywny wynik testów akceptacyjnych oraz badań certyfikacyjnych i osiągnęło IX poziom gotowości technologii.
Upamiętnianie w zdecentralizowanej formule
- Agnieszka Gębczyńska-Janowicz
2021
Realizacje kommemoratywne tworzone obecnie w przestrzeni publicznej udowadniają, e definicja pomnika jest niejednoznaczna, wynika z różnych aspektów twórczości i dostosowuje się do kontekstu kulturowego epoki. Celem artykułu jest analiza współczenej realizacji formuły zdecentralizowanej.
Uptake, accumulation, and translocation of Zn, Cu, Pb, Cd, Ni, and Cr by P. australis seedlings in an urban dredged sediment mesocosm: impact of seedling origin and initial trace metal content
- Nicole Nawrot
- Ewa Wojciechowska
- Ksenia Pazdro
- Jacek Szmagliński
- Janusz Pempkowiak
2021 Pełny tekst SCIENCE OF THE TOTAL ENVIRONMENT
The study presents results from 6 months of phytoremediation of sediments dredged from three urban retention tanks carried out in a mesocosm setup with the use of P. australis. Two kinds of P. australis seedlings were considered: seedlings originating from natural (uncontaminated - Suncont) and anthropogenically changed environments (contaminated – Scont); this distinction was reflected in the baseline concentrations of trace metals inside their tissues. The potentially toxic elements (PTEs) considered in this study were as follows: Zn, Cu, Cd, Ni, Cr, and Pb. The aim of the study was to compare the uptake, accumulation, and translocation properties of seedlings with different initial trace metal contents. The PTE concentrations were analyzed in sediments as well as in belowground and aboveground parts of plants in the middle (3rd month) and at the end of the investigation period using inductively coupled plasma mass spectrometry (ICP-MS), and the accumulation of PTEs in plant tissues was calculated. Phytoextraction efficiency was evaluated using the bioconcentration factor (BF) and translocation factor (TF). Plant morphology was assessed with scanning electron microscopy (SEM) to document plant stress due to PTE exposure. The results of our study indicated that P. australis seedlings originating from sites differing in the initial trace metal content exhibited different behavior when grown on sediments dredged from urban retention tanks. Suncont seedlings with low initial metal contents tended to adapt to the dredged sediments and showed phytoextraction ability, while Scont seedlings originating from sites with initial high contents of trace metals acted as phytoexcluders and tended to release PTEs from their tissues into the sediments. The morphological and structural effects caused by metal toxicity were observed in growth limitation, root tissue disturbance, root hair number decrease, and structural alterations in the epidermis and endodermis. Therefore, the Suncont seedlings presented better properties and adaptability for phytoremediation purposes.
Urban Lighting Research Transdisciplinary Framework—A Collaborative Process with Lighting Professionals
- Catherine Vega, Pérez
- Karolina Zielińska-Dąbkowska
- Franz Hölker
2021 Pełny tekst International Journal of Environmental Research and Public Health
Over the past decades, lighting professionals have influenced the experience of the night by brightly illuminating streets, buildings, skylines, and landscapes 24/7. When this became the accepted norm, a dual perspective on night-time was shaped and the visual enjoyment of visitors after dusk was prioritized over natural nightscapes (nocturnal landscapes). During this time, researchers of artificial light at night (ALAN) observed and reported a gradual increase in unnatural brightness and a shift in color of the night-time environment. As a consequence, ALAN has been identified as a relevant pollutant of aquatic and terrestrial habitats, and an environmental stressor, which may adversely affect a wide range of organisms, from micro-organisms to humans. Unfortunately, lighting professionals and ALAN researchers usually attempt to solve today’s sustainable urban lighting problems distinctive to their fields of study, without a dialogue between research and practice. Therefore, in order to translate research knowledge as an applicable solution for the lighting practice and to minimize the impact on the environment, a collaborative framework involving a transdisciplinary process with lighting professionals is crucial to potentially bring the practice, research, production, decision-making, and planning closer to each other. This paper presents a framework to help reduce the existing gap of knowledge, because appropriate lighting applications depend upon it. Access to less light polluted nightscapes in urban environments is just as important as access to unpolluted water, food, and air. This call for action towards sustainable urban lighting should be included in future lighting policies to solve the urgent environmental and health challenges facing our world.
Use of Bi-Temporal ALS Point Clouds for Tree Removal Detection on Private Property in Racibórz, Poland
- Patrycja Przewoźna
- Paweł Hawryło
- Karolina Zięba-kulawik
- Adam Inglot
- Krzysztof Mączka
- Piotr Wężyk
- Piotr Matczak
2021 Pełny tekst Remote Sensing
Trees growing on private property have become an essential part of urban green policies. In many places, restrictions are imposed on tree removal on private property. However, monitoring compliance of these regulations appears difficult due to a lack of reference data and public administration capacity. We assessed the impact of the temporary suspension of mandatory permits on tree removal, which was in force in 2017 in Poland, on the change in urban tree cover (UTC) in the case of the municipality of Racibórz. The bi-temporal airborne laser scanning (ALS) point clouds (2011 and 2017) and administrative records on tree removal permits were used for analyzing the changes of UTC in the period of 2011–2017. The results show increased tree removal at a time when the mandatory permit was suspended. Moreover, it appeared that most trees on private properties were removed without obtaining permission when it was obligatory. The method based on LiDAR we proposed allows for monitoring green areas, including private properties.
Using deep learning to increase accuracy of gaze controlled prosthetic arm
- Tomasz Kocejko
2021
This paper presents how neural networks can be utilized to improve the accuracy of reach and grab functionality of hybrid prosthetic arm with eye tracing interface. The LSTM based Autoencoder was introduced to overcome the problem of lack of accuracy of the gaze tracking modality in this hybrid interface. The gaze based interaction strongly depends on the eye tracking hardware. In this paper it was presented how the overall the accuracy can be slightly improved by software solution. The cloud of points related to possible final positions of the arm was created to train Autoencoder. The trained model was next used to improve the position provided by the eye tracker. Using the LSTM based Autoencoder resulted in nearly 3% improvement of the overall accuracy.
Using Evidence-based Arguments to Support Dependability Assurance - Experiences and Challenges
- Janusz Górski
2021 ACM SIGAda Ada Letters
The presentation introduces to the problem of evidence-based arguments and their applications. Then, based on the experiences collected during development and commercial deployment of a concrete solution to this problem (system NOR-STA) we overview selected challenges and the ways of addressing them.
Using FreeFEM open software for modelling the vibrations of piezoelectric devices
- Marek Moszyński
2021 Pełny tekst Vibrations in Physical Systems
Modelling vibrations of piezoelectric transducers has been a topic discussed in the literature for many decades. The first models - so-called one-dimensional - describe the vibrations only near operating frequency and near its harmonics. Attempts to introduce two-dimensional models were related to the possibility of one transducer working at several frequencies, including both thickness vibrations and those resulting from the transducer horizontal dimensions. In recent decades, thanks to the use of the finite element method and its derivatives, and the progress related to the increase in processor speed and memory availability, the implementation of models based on three-dimensional modelling is possible using software on personal computers. As the implementation of finite element method algorithms is characterized by high complexity, several professional software packages have been created on the commercial market, among which only a few implement the piezoelectric equations. In this context, this article presents how to use open source software along with developed programming language for intuitive definition of piezoelectric equations and its solution.
Using the ultrasonic tomography method to study the condition of wooden beams from historical buildngs
- Monika Zielińska
- Magdalena Rucka
2021
The need to evaluate the integrity of wooden structural elements is constantly increasing. Non-destructive methods are becoming more popular in this field of research. One type of non-destructive testing is the ultrasonic imaging method, which allows the analysis of internal wood structures without disturbing their state and integrity. In this study, we are interested in assessing the effect of wood condition on the ultrasound time of flight (TOF). The research was carried out on wooden beams, which were obtained from a historical building. The images obtained from ultrasound tomography were compared with results of a visual inspection.Places of discontinuities, voids and cracks in wood caused a much lower velocity of wave propagation.The location of the wood core was illustrated by the places with the highest velocity. The article proved the validity of using ultrasonic tomography to assess the technical condition of historic wooden beams.
Ustawa a autonomia statutowa w Polsce i w Ukrainie: rozwiązania statutowe w sferze governance wybranych uczelni polskich i ukraińskich
- Krzysztof Leja
- Viacheslav Komarov
- Iryna Degtyarova
2021
Kierując się zasadą autonomii uczelni i deregulacji prawa oraz właściwym miejscem statutu w systemie źródeł prawa, w ramach tego rozdziału postanowili-śmy poddać analizie statuty wybranych uczelni w Polsce i w Ukrainie, na tle roz-wiązań ustawowych na podstawie następujących pytań badawczych:• W jaki sposób i w jakim stopniu uczelnie korzystają z uprawnień autonomicznych (w zakresie autonomii organizacyjnej) i potencjału Ustawy w swoich statutach? • Jakie sfery reguluje ustawa, a jakie statut? Czy i w jakim zakresie istnieje do-mniemanie właściwości statutów do regulowania spraw nieobjętych regulacją ustawową?• Czy statut przedstawia bardzo szczegółowe podejście, czy tylko ramy? Czy może statut odzwierciedlać sposób i charakter uczelnianej społeczności aka-demickiej (jako „polityczne” porozumienie wszystkich grup interesów?)
Uszkodzenia pożarowe dachu budynku kościoła pw. Świętych Apostołów Piotra i Pawła
- Tomasz Majewski
- Maciej Niedostatkiewicz
2021 Pełny tekst Przegląd Budowlany
W artykule przedstawionopsi działń podjętych po pożarze dachu zabytkowego Kcioła pw. Świętych Apostołów Piotra i Pawła w Gdańsku
Utilizing pulse dynamics for non-invasive Raman spectroscopy of blood analytes
- Maciej Wróbel
- Jeong Hee Kim
- Piyush Raj
- Ishan Barman
- Janusz Smulko
2021 Pełny tekst BIOSENSORS & BIOELECTRONICS
Non-invasive measurement methods offer great benefits in the field of medical diagnostics with molecular-specific techniques such as Raman spectroscopy which is increasingly being used for quantitative measurements of tissue biochemistry in vivo. However, some important challenges still remain for label-free optical spectroscopy to be incorporated into the clinical laboratory for routine testing. In particular, non-analyte-specific variations in tissue properties introduce significant variability of the spectra, thereby preventing reliable calibration. For measurements of blood analytes such as glucose, we propose to decrease the interference from individual tissue characteristics by exploiting the known dynamics of the blood-tissue matrix. We reason that by leveraging the natural blood pulse rhythm, the signals from the blood analytes can be enhanced while those from the static components can be effectively suppressed. Here, time-resolved measurements with subsequent pulse frequency estimation and phase-sensitive detection are proposed to recover the Raman spectra correlated with the dynamic changes at blood-pulse frequency. Pilot in vivo study results are presented to establish the benefits as well as outline the challenges of the proposed method in terms of instrumentation and signal processing.
Validation of Hydraulic Mechanism during Blowout Trauma of Human Orbit Depending on the Method of Load Application
- Marcin Zmuda Trzebiatowski
- Paweł Kłosowski
- Andrzej Skorek
- Krzysztof Żerdzicki
- Paweł Lemski
- Mateusz Koberda
2021 Pełny tekst Applied Bionics and Biomechanics
The more we know about mechanisms of the human orbital blowout type of trauma, the better we will be able to prevent them in the future. As long as the buckling mechanism’s veracity is not in doubt, the hydraulic mechanism is not based on equally strong premises. To investigate the correctness of the hydraulic mechanism’s theory, two different methods of implementation of the hydraulic load to the finite element method (FEM) model of the orbit were performed. The intraorbital hydraulic pressure was introduced as a face load applied directly to the orbit in the first variant, while in the second one the load was applied to the orbit indirectly as a set of nodal forces transferred from the external surface of the eyeball via the intraorbital tissues to the orbital walls within the contact problem. Such an approach is aimed at a better understanding of the pattern for the formation of blowout fractures during the indirect load applied to the orbital bones. The nonlinear dynamic analysis of both numerical models showed that the potential fracture was observed in the second variant only, embracing a relatively large area: both medial and lower wall of the orbit. Interestingly, the pressure generated by the intraorbital entities transferred the energy of the impact to the orbital sidewalls mainly; thus, the nature of the mechanism known as the hydraulic was far from the expected hydraulic pressure. According to the eyeball’s deformation as well as the areas of the greatest Huber-Mises-Hencky (H-M-H) stress within the orbit, a new term of strut mechanism was proposed instead of the hydraulic mechanism as more realistic regarding the investigated phenomenon. The results of the current research may strongly influence the development of modern implantology as well as affect forensic medicine.
Validation study on a new semi-empirical method for the prediction of added resistance in waves of arbitrary heading in analyzing ship speed trial results
- Jinbao Wang
- Sebastian Bielicki
- Florian Kluwe
- Hideo Orihara
- Gongzheng Xin
- Kenichi Kume
- Semyun Oh
- Shukui Liu
- Peiyuan Feng
2021 OCEAN ENGINEERING
This paper describes an open and extensive validation study carried out by the Specialist Committee on Ships in Operation at Sea (SOS) of the International Towing Tank Conference (ITTC) on the newly developed SHOPERA-NTUA-NTU-MARIC (SNNM) wave-added resistance prediction method. The SNNM method aims at a simple, fast and transparent determination of the added resistance in regular waves of arbitrary encounter directions, even when the hull geometry is not available. Prior to the validation study, a series of acceptance criteria for the new method were specified by the committee. Contributions of 1,477 added resistance experimental data samples from 8 institutions were collected, analyzed and cross-checked with satisfactory outcome, which finally led to the inclusion of the new method into the ITTC recommended sea trial procedure as an important progress. Some aspects of concerns are discussed in detail and further work in the future is recommended.
Valorization of waste cabbage leaves by postharvest photochemical treatments monitored with a non-destructive fluorescence-based sensor
- Artur Kowalski
- Giovanni Agati
- Maria Grzegorzewska
- Ryszard Kosson
- Barbara Kusznierewicz
- Tomasz Chmiel
- Agnieszka Bartoszek-Pączkowska
- Lorenza Tuccio
- Daniele Grifoni
- Ingunn M. Vagen
- Stanislaw Kaniszewski
2021 Pełny tekst JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY
The biosynthesis of polyphenolic compounds in cabbage waste, outer green leaves of white head cabbage (Brassica oleracea L. var. capitata subvar. alba), was stimulated by postharvest irradiation with UVB lamps or sunlight. Both treatments boosted the content of kaempferol and quercetin glycosides, especially in the basal leaf zone, as determined by the HPLC analysis of leaf extracts and by a non-destructive optical sensor. The destructive analysis of samples irradiated by the sun for 6 days at the end of October 2015 in Skierniewice (Poland) showed an increase of leaf flavonols by 82% with respect to controls. The treatment by a broadband UVB fluorescent lamp, with irradiance of 0.38 W m−2 in the 290–315 nm range (and 0.59 W m−2 in the UVA region) for 12 h per day at 17 °C along with a white light of about 20 μmol m−2 s−1, produced a flavonols increase of 58% with respect to controls. The kinetics of flavonols accumulation in response to the photochemical treatments was monitored with the FLAV non-destructive index. The initial FLAV rate under the sun was proportional to the daily radiation doses with a better correlation for the sun global irradiance (R2 = 0.973), followed by the UVA (R2 = 0.965) and UVB (R2 = 0.899) irradiance. The sunlight turned out to be more efficient than the UVB lamp in increasing the flavonols level of waste leaves, because of a significant role played by UVA and visible solar radiation in the regulation of the flavonoid accumulation in cabbage. The FLAV index increase induced on the adaxial leaf side was accompanied by a lower but still significant FLAV increase on the unirradiated abaxial side, likely due to a systemic signaling by mean of the long-distance movement of macromolecules. Our present investigation provides useful data for the optimization of postharvest photochemical protocols of cabbage waste valorization. It can represent a novel and alternative tool of vegetable waste management for the recovery of beneficial phytochemicals.
Vibro piles performance prediction using result of CPT
- Paweł Więcławski
2021 Pełny tekst Studia Geotechnica et Mechanica
Vibro piles belong to the group of full displacement piles with an expanded base, characterised by a very high load capacity, especially in non-cohesive soils. The problem is to adopt a reliable method for the determination of full load–settlement (Q–s) curve. A frequent difficulty is the determination of the load capacity limit based on the static load test because the course of the load–settlement curve is of a linear nature. This publication presents the empirical method. It allows direct prediction of a full axially loaded pile settlement curve based on the values of qc cone resistance obtained in cone penetration test (CPT). The advantage offered by this procedure is the accuracy of the obtained limit values in relation to the actual load-bearing capacity as compared to other methods based on soil parameters obtained in in situ testing. An additional advantage is the Q–s characteristics, which enable designing for intermediate values, allowing for the criterion of minimal or equal settlements. The shape of analytical curves was compared with static pile load test (SPLT) curves. This comparison showed large convergences between the analytical and measured curves.
Virulence of Clinical Candida Isolates
- Martyna Mroczyńska
- Anna Brillowska-Dąbrowska
2021 Pełny tekst Pathogens
The factors enablingCandidaspp. infections are secretion of hydrolytic enzymes, adher-ence to surfaces, biofilm formation or morphological transition, and fitness attributes. The aim of thisstudy was to investigate the correlation between known extracellular virulence factors and survivalofGalleria mellonellalarvae infected with clinicalCandida. The 25 isolates were tested and the activityof proteinases among 24/24, phospholipases among 7/22, esterases among 14/23, hemolysins among18/24, and biofilm formation ability among 18/25 isolates was confirmed. Pathogenicity investiga-tion usingG. mellonellalarvae as host model demonstrated thatC. albicansisolates andC. glabrataisolate were the most virulent andC. kruseiisolates were avirulent.C. parapsilosisvirulence wasidentified as varied,C. inconspicuawere moderately virulent, and oneC. palmioleophilaisolate was oflow virulence and the remaining isolates of this species were moderately virulent. According to ourstudy, virulence ofCandidaisolates is related to the expression of proteases, hemolysins, and esterases.
Visegrád countries' scientific productivity in the European context: a 10-year perspective using Web of Science and Scopus
- Magdalena Szuflita-Żurawska
- Beata Basińska
2021 Pełny tekst LEARNED PUBLISHING
Measuring the growth of research productivity is a core element of performance in the higher education sector. This paper aims to analyse the scientific productivity of the Visegrád Group countries (2010-2019) based on data from the WoS and Scopus databases as well as data from secondary sources (demographic and socio-economic factors). Quantitatively, although Poland has the highest output, this is due to its comparative size, whereas output per researcher in Poland is lower than in other V4 countries. As regards the qualitative approach, Hungary and the Czech Republic are significantly more effective in terms of scientific collaboration and receive a greater number of European Research Council grants. Thus, bibliometric data in relation to cross-country characteristic indicators (socio-economic variables including expenditure on science and having prestigious universities) are related to the positions of the V4 countries. Practical implications suggest that university management within the Visegrád Group must develop and continue strategies to strengthen international collaboration between researchers in order to accelerate change in the dissemination of scientific output at the global level. Academic scholarly publishers may benefit from publishing research on specific issues important to different regions of the world in order to expand their audience and gain new potential resources.