2021 - Repozytorium publikacji - Politechnika Gdańska

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Can bottom sediments be a prospective fertilizing material? A chemical composition analysis for potential reuse in agriculture.
- Karolina Matej-Łukowicz
- Ewa Wojciechowska
- Joanna Strycharz
- Marta Szubska
- Karol Kuliński
- Jacek Bełdowski
- Aleksandra Winogradow
2021 Pełny tekst Materials
Every year huge amounts of bottom sediments are extracted worldwide, which need to be dis-posed. The recycling of bottom sediments for soil fertilization is in line with the long-promoted circular economy policy and enables the use of micro and macronutrients accumulated in sedi-ments for soil fertilization. When considering potential agricultural reuse of the dredge sediments, the first necessary step should be to analyze whether the heavy metal content meets the obligatory criteria. Then, the contents of valuable elements required for plant growth and their ratios should be assessed. In this study, the content of nitrogen, organic carbon, phosphorus and potassium was tested and iron, sulfur, calcium and magnesium were also analysed along vertical profiles of sed-iments extracted from 4 urban retention tanks in Gdańsk (Poland). The sediments were indicated to have a low content of nutrients (Ntot 0.01-0.52%, Corg 0.1-8.4%, P₂O₅ 0.00-0.65%, K 0.0-1.0%) while being quite rich in Fe and S (0.2-3.3%, 0.0-2.5% respectively). The C/N ratio changed in the range of 17.4-28.4, which proved good nitrogen availability for plants. The mean values of the Fe/P ratio were above 2.0, which confirms that phosphorus in the sediments would be available to the plants in the form of iron phosphate. To sum up, the bottom sediments from municipal reten-tion reservoirs are not a perfect material for soil fertilization, but they are a free waste material which, when enriched with little cost, can become a good fertilizer. Future research should focus on cultivation experiments with the use of sediments enriched with N, P, Corg.
Can the Pandemic Be a Catalyst of Spatial Changes Leading Towards the Smart City?
- Barbara Zgórska
- Dorota Kamrowska-Załuska
- Piotr Lorens
2021 Pełny tekst Urban Planning
The worldwide spread of Covid‐19 infections has had a pervasive influence on cities and the lives of their residents. The current crisis has highlighted many urban problems, including those related to the functionality of urban structures, which directly affect the quality of life. Concurrently, the notion of “smart cities” is becoming a dominant trend in the discourse on urban development. At the intersection of these two phenomena, questions about the effects of Covid‐19 on the future of cities arise. These are concerned with the possible roles of the pandemic in the process of urban regeneration and the development of smart solutions. The article aims to create a conceptual framework that will allow researchers to assess the influence of Covid‐19‐related changes on urban structures and their functionality in the following areas: city structure, connectivity and mobility, public spaces, access to green areas, and digital transformation. In the empirical part of the article, the influence of pandemic‐caused changes on the development of various aspects of smart cities is discussed. The article concludes with an analysis of the effects the pandemic might have on digital urban regeneration
Can Web Search Queries Predict Prices Change on the Real Estate Market?
- Nina Rizun
- Anna Baj-Rogowska
2021 Pełny tekst IEEE Access
This study aims to explore whether the intensity of internet searches, according to the Google Trends search volume index (SVI), is a predictor of changes in real estate prices. The motivation of this study is the possibility to extend the understanding of the extra predictive power of Google search engine query volume of future housing price change (shift direction) by (i) the introduction of a research approach that combines the advantages of the complementary use of cross-correlation analysis and machine learning classification algorithms; (ii) applying the multi-class HPI values classifier which allows predicting the housing price increase, decrease or relative stability; (iii) exploiting the SVI that relates to interests in both ‘real estate’ and ‘credit to buy real estate’; (iv) evaluation of the introduced approach in the context of the Polish real estate market. The main theoretical contribution of our work is a confirmation that the freely available information regarding Google user searches can provide an in-depth insight into enriching the generally accepted statistics on supply and demand in the real estate market. From the practical perspective, this research confirms that SVI can be associated as a sole determinant to anticipate the housing price change with time-lag sufficient for making decisions regarding the purchase (sale) of individual property or the real estate market control. Such findings can be also helpful for researchers who intend to use Google Trends data as an extra variable from demand side to improve the prediction accuracy if it is included in the model which is based on the existing housing prices determinants.
CaO-based high temperature CO2 sorbents – Literature review
- Donata Konopacka-Łyskawa
- Natalia Czaplicka
- Andrzej Szefer
2021 Pełny tekst Chemical and Process Engineering : New Frontiers
The use of CaO-based adsorbents has a high potential to capture CO2 from various systems due to its high reactivity with CO2, high capacity, and low cost of naturally derived CaO. The application of CaO-based sorbents to remove carbon dioxide is based on a reversible reaction between CaO and CO2. However, multiple carbonation/calcination cycles lead to a rapid reduction in the sorption capacity of natural CaO, and therefore efforts are made to reduce this disadvantage by doping, regenerating, or producing synthetic CaO with stable sorption properties. In this review, the synthesis methods used to obtain CaO-based sorbents were collected, and the latest research on improving their sorption properties was presented. The most commonly used models to describe the CO2 sorption kinetics on CaO-based sorbents were also introduced. The methods of sorbent regeneration and their effectiveness were summarized. In the last part of this review, the current state of advancement of work on the larger scale, possible problems, and opportunities during scale-up of the calcium looping process were presented. Concluding (i) the presented methods of adsorbent synthesis allow for the production of doped CaO adsorbents on a laboratory scale, characterized by high CO2 capture efficiency and good cyclic stability, (ii) the most commonly used in practice models describing CO2 chemisorption are empirical models and the shrinking core model, (iii) the use of sorbent regeneration allows for a significant improvement in sorption capacity, (iv) the scale-up of both the production of new CaO adsorbents and the CO2 capture technology with their use requires further development.
Carbon nanoarchitectures as high-performance electrodes for the electrochemical oxidation of landfill leachate
- Mattia Pierpaoli
- Paweł Jakóbczyk
- Mirosław Sawczak
- Aneta Łuczkiewicz
- Sylwia Fudala-Książek
- Robert Bogdanowicz
2021 Pełny tekst JOURNAL OF HAZARDOUS MATERIALS
Nanomaterials and assemblies of the aforementioned into complex architectures constitute an opportunity to design efficient and selective solutions to wide spread and emerging environmental issues. The limited disposal of organic matter in modern landfills generates extremely concentrated leachates characterised by high concentrations of refractory compounds. Conventional biochemical treatment methods are unsuitable, while advanced treatment, such coagulation, reverse osmosis and ultrafiltration can be very costly and generate additional waste. Electrochemical oxidation is an established technique to efficiently mineralise a plethora of recalcitrant pollutants, however the selectivity and efficiency of the process are strongly related to the anode material. For this reason, a nanoarchitectured carbon material has been designed and synthesised to improve the capability of the anode towards the adsorption and decomposition of pollutants. Instead of simple nanostructures, intelligently engineered nanomaterials can come in handy for more efficient advanced treatment techniques. In this study, a carbon nanoarchitecture comprising boron-doped vertically aligned graphene walls (BCNWs) were grown on a boron-doped diamond (BDD) interfacial layer. The results show how the peculiar maze-like morphology and the concurrence of different carbon hybridisations resulted in a higher current exchange density. The BDD performed better for the removal of NH4+ while the BCNW-only sample exhibited a faster deactivation. The BDD/BCNW nanoarchitecture resulted in an enhanced COD removal and a NH4+ removal similar to that of BDD, without the intermediate production of NO2− and NO3−.
Cascade Object Detection and Remote Sensing Object Detection Method Based on Trainable Activation Function
- S. N. Shivappriya
- M. Jasmine Pemeena Priyadarsini
- Andrzej Stateczny
- C. Puttamadappa
- B. D. Parameshachari
2021 Pełny tekst Remote Sensing
Object detection is an important process in surveillance system to locate objects and it is considered as major application in computer vision. The Convolution Neural Network (CNN) based models have been developed by many researchers for object detection to achieve higher performance. However, existing models have some limitations such as overfitting problem and lower efficiency in small object detection. Object detection in remote sensing hasthe limitations of low efficiency in detecting small object and the existing methods have poor localization. Cascade Object Detection methods have been applied to increase the learning process of the detection model. In this research, the Additive Activation Function (AAF) is applied in a Faster Region based CNN (RCNN) for object detection. The proposed AAF-Faster RCNN method has the advantage of better convergence and clear bounding variance. The Fourier Series and Linear Combination of activation function are used to update the loss function. The Microsoft (MS) COCO datasets and Pascal VOC 2007/2012 are used to evaluate the performance of the AAF-Faster RCNN model. The proposed AAF-Faster RCNN is also analyzed for small object detection in the benchmark dataset. The analysis shows that the proposed AAF-Faster RCNN model has higher efficiency than state-of-art Pay Attention to Them (PAT) model in object detection. To evaluate the performance of AAF-Faster RCNN method of object detection in remote sensing, the NWPU VHR-10 remote sensing data set is used to test the proposed method. The AAF-Faster RCNN model has mean Average Precision (mAP) of 83.1% and existing PAT-SSD512 method has the 81.7%mAP in Pascal VOC 2007 dataset.
Case study of water vapour transmission properties of EPDM façade membranes
- Andrzej Ambroziak
- Sławomir Dobrowolski
2021 Pełny tekst Archives of Civil Engineering
This research aimed to investigate the water vapour transmission properties of chosen EPDM membranes applied in façade and window systems under laboratory tests. The applied procedure included in national and international standards utilized for the laboratory tests of water vapour transmission properties of EPDM membrane is described. Two main types (outside and inside types) of EPDM membranes are laboratory tested. The authors indicated that the EPDM membranes should differ in surface factures. Nevertheless, some manufacturers mark EPDM membranes on each roll (on the package only) without different permanent denotations on the EPDM membranes surfaces. This form of denotations can cause using problems-using the wrong types of the EPDM aprons in building partitions, because when the package is removed there is impossible to visually identify the type of EPDM membrane (outside or inside type) from the texture of the membrane surface. The experimental results of laboratory tests indicated using the wrong type of EPDM membrane in the inside aprons in building partitions in the investigated façade window system. The designed proportion of the sd values (the resistance to movement of water vapour) of inside and outside EPDM façade membranes should be designed equally to about 3.0 (recommended value 4) to provide proper diffusion properties of partitions around windows in façade systems. The paper can provide scientists, engineers, and designers an experimental basis in the field of the EPDM membranes water vapour transmission properties applied to façades and windows systems.
Cassirer E. Język i mit. Przyczynek do zagadnienia imion bogów.Przekład, wstęp i opracowanie: Przemysław Parszutowicz.. Wydaw. Marek Drzewiecki,2021
- Przemysław Parszutowicz
2021
Rozprawa Cassirera pochodzi z najważniejszego bodaj okresu jego twórczości – okresu współpracy z Biblioteką Warburga – i mimo niewielkich rozmiarów jest w dużej mierze reprezentatywna, tak gdy idzie o wykorzystywaną przez niego metodę, jak i o główny obszar jego zainteresowań badawczych. Stanowi bezpośrednie nawiązanie do rozprawy Hermanna Usenera Götternamen. Versuch einer Lehre von der religiösen Begriffsbildung. Pod względem swojej treści książka przedstawia silną korelację języka i mitu, słowa i magii, biorąc za punkt wyjścia twierdzenie o zasadniczej zgodności istoty bóstwa z jego imieniem. Opisuje przykłady sprawczej siły słowa w świecie opanowanym przez myślenie mityczne i przez to wskazuje na zasady i swoistą „logikę” mitu. Język przedstawia tutaj to, co myślenie mityczne bezpośrednio wyraża: odzwierciedlenie całości w każdym szczególe, przyczynowość opartą na celowym działaniu jakiegoś podmiotu, a zatem uduchowienie i personifikację przyrody, oparcie na zmysłowym, bezpośrednim oglądzie, na bezpośredniej zmysłowej obecności.
CEL FUNKCJONOWANIA, ZADANIA I OBSZARY BADAWCZE CENTRUM MORSKIEJ ENERGETYKI WIATROWEJ POLITECHNIKI GDAŃSKIEJ
- Zbigniew Korczewski
2021 Pełny tekst Journal of Polish CIMEEAC
W artykule przybliżono wybrane aspekty funkcjonowania Centrum Morskiej Energetyki Wiatrowej w Politechnice Gdańskiej. Scharakteryzowano główne zadania Centrum oraz wstępnie zdefiniowane obszary badawcze, w których specjalizują się naukowcy reprezentujący niemal wszystkie wydziały akademickie Uczelni (oprócz Wydziału Architektury). Przedstawiono kierunki działania Centrum w perspektywie kilku najbliższych lat, w wyniku których nastąpi weryfikacja i konieczne doprecyzowanie obszarów badawczych, zgodnie z oczekiwaniami inwestorów morskich farm wiatrowych budowanych w polskiej wyłącznie strefie ekonomicznej Morza Bałtyckiego.
Cellulosic bionanocomposites based on acrylonitrile butadiene rubber and Cuscuta reflexa: adjusting structure-properties balance for higher performance
- Midhun Dominic C.D.
- Rani Joseph
- P.M. Sabura Begum
- Athira S Kumar
- P. A. Jeemol
- Thomasukutty Jose
- Dileep Padmanabhan
- Krzysztof Formela
- Suchart Siengchin
- Jyotishkumar Parameswaranpillai
- Mohammad Saeb
2021 CELLULOSE
Design and manufacture of cellulosic nanocomposites with acceptable performance is in the period of a transition from fantasy to reality. Typically, cellulosic nanofillers reveal poor compatibility with polymer matrices. Thus, adjusting the balance between structure and properties of cellulosic bionanocomposites by careful selection of parent ingredients is the first priority. Herein, we incorporated Cuscuta reflexa derived cellulose nanofibers (CNFs) into acrylonitrile-butadiene rubber (NBR) for high-performance elastomeric applications. Tensile and tear strength of NBR improved by ~ 125 and ~ 105 %, respectively at a very low loading of 4 phr CNFs, as a result of interfacial bonding, as evidenced by fractographic analysis. In parallel, the temperature at which maximum degradation occurs (Tmax) of NBR rose by 14 °C. The swelling index and molar uptake of toluene were also lowered. The Wolff-activity coefficient, hardness, abrasion resistance, and cross-link density were all improved correspondingly. The positive shift in glass transition temperature and the fall in the loss tangent peak height for bionanocomposites proved the effective immobilization of NBR chains by well-dispersed CNFs. The hydrogen bonding interaction between –OH groups of CNFs and –CN groups of NBR might be responsible for the superior performance of NBR/CNF composites, which is confirmed by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction analysis (XRD).
Cement kiln dust
- Hakim S. Abdelgader
- Mugahed Amran
- Marzena Kurpińska
- Mohammad Mosaberpanah
- Gunasekaran Murali
- Roman Fediuk
2021
The volume of cement production in the world has remained at the level of approxi mately 4.1 billion tons/year. The cement production process is energy intensive and is the world’s leading emitter of carbon dioxide. Therefore, the main activities cement plants are aimed at introducing technologies changes in production of clinkier.The construction industry is responsible for the majority of CO2 emissions to the atmosphere: the industry emits 30% of total CO2, building emits 28%, transportation is responsible for 22% of CO2, the production of building materials causes 11% of CO2 emissions, including the cement industry is responsible for around 7% of emissions CO2. Other industries are responsible for around 9% of CO2 emissions to the atmosphere. The process of burning raw materials for the production of clinker is the most important stage of the entire cement production process. Cement kiln dust (CKD) is waste generated during the production of clinker. The dust collected in the dust collectors is partly reused in the production process and some is stored. The storage method is not preferred due to its operations negative en vironmental impact. If the dust contains alkalis, chlorides, sulphates, or heavy metals, they cannot be recycled. Generally cement plants strive to reduce the formation of dust. About 1.5 tons of raw materials are used to produce 1 ton of clinker. After the extraction, grinding, and homogenization of raw materials, the process of calcination of calcium carbonate takes place. The source of calcium carbonate is naturally occurring limestone deposits, namely limestone, marl, or chalk. Then, to obtain clinker, calcium oxide is sintered with silica, aluminum oxide, and iron oxide at a temperature of 1450°C. Most often, clinker is fired using the dry or wet method in a long rotary kiln. After firing, the clinker is ground together with the binding regulator - gypsum and additives. To generate the heat needed to burn the clinker, fossil fuels such as petcoke, hard coal, lignite, and fuel oil or natural gas are used. Due to proecological activities, secondary solid fuels are used as alternative fuels as substitutes for fossil fuels. The amount of thermal energy obtained from their combustion currently accounts for about 85% of the total amount of thermal energy used in the clinker burning process. These changes lead to effective energy management through the efficient use of natural and alternative fuels.
Cerclage cable augmentation does not increase stability of the fixation of intertrochanteric fractures. A biomechanical study
- Marcin Ceynowa
- Krzysztof Żerdzicki
- Paweł Kłosowski
- Rafał Pankowski
- Marek Rocławski
- Tomasz Mazurek
2021 Orthopaedics & Traumatology-Surgery & Research
Background: Intertrochanteric fractures with a posteromedial intermediate fragment are unstable because of the loss of medial support. Additional fixation with a cerclage is used in subtrochanteric fractures, but not in intertrochanteric fractures. The aim of this biomechanical study is to evaluate whether cerclage fixation improves stability of intertrochanteric fractures. Hypothesis: Our hypothesis is that the cerclage fixation of the intermediate fragment increases fixation stability of intertrochanteric fractures.Materials and methods: Synthetic femora with intertrochanteric fractures (AO 31.A1.3) with a posteromedial fragment were fixed with a long gamma nail. The intermediate fragment was fixed with a cerclage cable. Four groups were compared: 1: no cable fixation; 2: anatomic reduction and cable fixation; 3:anatomic reduction and fixation of a fragment where its proximal part was removed simulating comminution; 4: non-anatomic reduction and cable fixation. The specimens were loaded axially in a testing machine. The preload was 100 N, followed by ten conditioning cycles from 100 N to 500 N. The test phase consisted of the cyclic loading between 100 N and the maximum force that increased at a rate of 50 N at each cycle until failure. The stiffness was calculated from the load/displacement curve of the last three conditioning cycles.Results: There were no statistically significant differences between force to failure (group 1: 681 N; group2: 846 N; group 3: 699 N; group 4: 806 N; ANOVA p = 0.23) and stiffness (group 1: 769 N/mm; group2: 819 N/mm; group 3: 815 N/mm; group 4: 810 N/mm; ANOVA p = 0.84) between groups. There were significant differences in the widening of the lag screw canal (group 1: 2.16 mm; group 2: 4.5 mm; group3: 3 mm; group 4: 2.5 mm; ANOVA p = 0.017). In individual comparison, the differences were significant only between the anatomical reduction group and the non-anatomical reduction (p = 0.04) and the no cable group (p = 0.02).Discussion: There is a controversy in clinical literature whether cable fixation improves treatment outcome of proximal femoral fractures. This study suggests that medial wall reconstruction with a cerclage cable does not improve axial stability of the fixation. Level of evidence: Not applicable; a biomechanical study.
CFD Simulations and Tests of a Prototype Flow Control Valve
- Marta Zaleska-Patrosz
- Piotr Patrosz
- Paweł Śliwiński
2021 Pełny tekst
In this paper a prototype of a flow control valve is described and numerically simulated. The flow control valve is used in hydraulic systems to maintain constant fluid flow despite changing loads of a receiver. The standard construction of this type of valves is modified mainly by eliminating the spring. The prototype consists the hydrostatically unloaded throttle valve and pressure ratio valve substituting pressure difference valve. The article concentrates on numerical simulation conducted for different positions of pressure ratio valve’s spool and various throttle valve settings. Additionally the rotation of the spool is included in simulation and its influence on valve’s characteristics is evaluated. The article also describes the methodology of determining flow characteristics of control valve. Results from numerical simulation are compared to results of experimental research.
CFFT columns in road through railroad crossings
- Eligiusz Mieloszyk
- Anita Milewska
- Marcin Abramski
2021
There were 12801 road through railroad one-level crossings in Poland in 2018. 215 accidents happened at them in 2018. In order to increase safety in rail and road traffic two-level crossings should be used. They are definitely safer and make the traffic more smooth. In the design and construction of two-level intersections of railway and road or path columns of circular cross-section are often used. They can be successfully replaced by CFFT columns (Concrete-Filled (Fibre-Reinforced Polymer) Tube). The advantage of CFFT columns is the possibility of their widespread use. As the research of these columns shows, including those conducted at the Gdansk University of Technology, they can carry significant compressive loads by their relatively small cross-section. They are resistant to corrosion and protect against corrosion concrete and its reinforcement (if used). In addition, it is worth adding that the electrical resistance of FRP composite is greater than 1GΩ, which is particularly important in the case of electrified railway lines or tram lines.
Chain Action - How Do Countries Add Value Through Digital Government?
- Jaromir Durkiewicz
- Tomasz Janowski
2021 Pełny tekst
This study examineshow countries develop and benefit from Digital Government(DG).The literature proposes various conceptualizations of the value-adding logic of DG, but the benchmarking practice is not respondingto such proposals.For instance, the United Nations’E-Government Surveycombines the readiness and uptake indicatorsand failsto cover any impactindicators;thus,its diagnostic valueis limited. To overcome this limitation, weintroduce a new assessment schemebased on the DG value chain conceptand pursue the question: how do the world countries add value in this chain?Reassembling the UN’s e-Government Survey indicatorsand the World Bank’s Worldwide Governance Indicators,we examine how the 191 UN Member States converted their readiness into uptakeanduptake into impactover the 2014-2018 period. The results rank the countries concerning their performance alongthe DG value chain, identify hotspots, and calculatethe value chain performance of regional and economic groups.
Challenges and opportunities related to the use of sewage sludge ash in cement-based building materials – A review
- Lesław Świerczek
- Bartłomiej Cieślik
- Piotr Konieczka
2021 Pełny tekst JOURNAL OF CLEANER PRODUCTION
Due to the increasingly demanding legal regulations, regarding both sewage sludge (SS) and solid residues obtained during its thermal utilization processes, new solutions to limit their negative impact on the environment are sought. One approach that eliminates the risk of sewage sludge ash (SSA) is its use in cement building materials. The article contains a detailed literature review regarding the use of SSA in mortars and concretes, where it is defined as the addition or substitute of the main binder. The issues of the impact of SSA quality (CaO content, the share of pozzolanic oxides, their ratio) on cement products are discussed in details. In addition to the description of the mechanical properties of building materials, the SSA impact on parameters such as workability, shrinkage of products and setting time is also described. It can be stated that using SSA in building industry is one of the most ecological approaches of SSA managing. Due to the toxic nature of SSA, data on the leaching of heavy metals from hardened mortar or concrete samples are presented to emphasize the contaminants immobilization effectiveness by cement products. Based on the analysis of the data presented in the article, solutions that can reduce the negative consequences of including SSA in building materials have been identified. However, due to the significant differences in SS thermal utilization technologic and SS characteristics, every SSA should be thoroughly characterized before implementing the most suitable stabilization/solidification methods
Challenges associated with development of AUV - unmanned autonomous underwater vehicles to be operated using the AI-based control systems
- Mirosław Gerigk
- Mateusz Gerigk
2021 Per mare ad astra
The last decade has been devoted towards further development of the UUV unmanned underwater vehicles which may be of two types. There are the USV unmanned surface vehicles and UUV unmanned underwater vehicles. There is a growing interest to work out and implement the fully advanced AUV autonomous underwater vehicles. The main drivers towards development of such the vehicles are the technologies of autonomous systems, sensors and effectors, innovative materials including the nano-materials and "intelligent" materials, innovative energy supply sources, innovative propulsion systems combining the efficient and silent both the engines and propellers, innovative IT technologies including the double mode air-underwater control, navigation and communication systems. The additional set of features the AUV vehicles may possess are the stealth-based and bio-technology-based solutions. The commercial applications of AUV vehicles may perform the conventional patrol and reconnaissance tasks. The navy devoted AUV vehicles may enable to perform the reconnaissance and combat missions. Despite of applications it is necessary to implement the advanced on-board hardware and software solutions to provide the high level of autonomy to the AUV vehicles. The general requirements to obtain an autonomous AUV vehicle are concentrated on the autonomy from the energy supply, self-control and self-navigation point of view. It may be associated with using no-communication with the centre of mission. Such the level of autonomy requires the innovative solutions concerning the vehicle's sensors, effectors and control. The biggest challenge associated with the AUV vehicles development is to work out and implement a kind of an intelligent AUV vehicle. A major difficulty to obtain such the vehicle is to acquire the precise data from the surrounding environment, to process these data and to use them to perform all the tasks and mission in real time domain. The AUV-AI-based vehicle should be equipped with a kind a mini-brain to compare the on-board simulated virtual reality with the reality outside the vehicle due to activity of sensors, mini-brain control system and effectors. Such the on-line comparison may enable to obtain the expected functionality, performance and safety of the AUV-AI-based vehicle for the benefit of mission.
Changes in Epigenetic Patterns Related to DNA Replication in Vicia faba Root Meristem Cells under Cadmium-Induced Stress Conditions
- Aneta Żabka
- Natalia Gocek
- Konrad Winnicki
- Paweł Szczeblewski
- Tomasz Laskowski
- Justyna Polit
2021 Pełny tekst Cells
Experiments on Vicia faba root meristem cells exposed to 150 µM cadmium chloride (CdCl2) were undertaken to analyse epigenetic changes, mainly with respect to DNA replication stress. Histone modifications examined by means of immunofluorescence labeling included: (1) acetylation of histone H3 on lysine 56 (H3K56Ac), involved in transcription, S phase, and response to DNA damage during DNA biosynthesis; (2) dimethylation of histone H3 on lysine 79 (H3K79Me2), correlated with the replication initiation; (3) phosphorylation of histone H3 on threonine 45 (H3T45Ph), engaged in DNA synthesis and apoptosis. Moreover, immunostaining using specific antibodies against 5-MetC-modified DNA was used to determine the level of DNA methylation. A significant decrease in the level of H3K79Me2, noted in all phases of the CdCl2-treated interphase cell nuclei, was found to correspond with: (1) an increase in the mean number of intranuclear foci of H3K56Ac histones (observed mainly in S-phase), (2) a plethora of nuclear and nucleolar labeling patterns (combined with a general decrease in H3T45Ph), and (3) a decrease in DNA methylation. All these changes correlate well with a general viewpoint that DNA modifications and post-translational histone modifications play an important role in gene expression and plant development under cadmium-induced stress conditions.
Changes on the Surface of the SiO2/C Composite, Leading to the Formation of Conductive Carbon Structures with Complex Nature of DC Conductivity
- Piotr Okoczuk
- Marcin Łapiński
- Tadeusz Miruszewski
- Piotr Kupracz
- Leszek Wicikowski
2021 Pełny tekst Materials
Sol–gel layers have been the subject of many studies in recent decades. However, very little information exists about layers in which carbon structures are developed in situ. Using the spin-coating method, we obtained thin iron-doped SiO2/C composite films. The results of Raman spectroscopy showed that our samples consisted of graphitic forms and polymers. The latter’s contribution decreases with rising temperature. FTIR and EDS studies show changes in carbon distribution on top of the layer, depending on the sintering temperature. The samples sintered at 800 C showed a significant increase in the contribution of carbon forms to the layer’s surface. Therefore, high conductivity can be observed in this sample. The results of XPS spectroscopy showed that the contribution of sp3 hybridized carbon increases after etching. The total electrical conductivity, studied by a DC four-wire technique, increased with the temperature and showed almost linear characteristics with significant changes below 150 K. The reduced activation energy plot has a positive temperature coefficient, which is a characteristic property of the conductive polymers in a metallic regime of conductivity.
Channel State Estimation in LTE-Based Heterogenous Networks Using Deep Learning
- Krzysztof Cwalina
- Piotr Rajchowski
- Alicja Olejniczak
- Olga Błaszkiewicz
- Robert Burczyk
2021 Pełny tekst SENSORS
Following the continuous development of the information technology, the concept of dense urban networks has evolved as well. The powerful tools, like machine learning, break new ground in smart network and interface design. In this paper the concept of using deep learning for estimating the radio channel parameters of the LTE (Long Term Evolution) radio interface is presented. It was proved that the deep learning approach provides a significant gain (almost 40%) with 10.7% compared to the linear model with the lowest RMSE (Root Mean Squared Error) 17.01%. The solution can be adopted as a part of the data allocation algorithm implemented in the telemetry devices equipped with the 4G radio interface, or, after the adjustment, the NB-IoT (Narrowband Internet of Things), to maximize the reliability of the services in harsh indoor or urban environments. Presented results also prove the existence of the inverse proportional dependence between the number of hidden layers and the number of historical samples in terms of the obtained RMSE. The increase of the historical data memory allows using models with fewer hidden layers while maintaining a comparable RMSE value for each scenario, which reduces the total computational cost.