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Search results for: maintenance
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Comparative Analysis of Two Polish Hyperbolic Systems AEGIR and JEMIOLUSZKA
PublicationGlobal Navigation Satellite System (GNSS) is seen by terrorists or hostile countries as a high value target. Volpe Center report contains the following statement: “During the course of its development for military use and more recent extension to many civilian uses, vulnerabilities of Global Navigation Satellite Systems (GNSS) – in the United States the Global Positioning System (GPS) – have become apparent. The vulnerabilities...
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Practical issues for the implementation of survivability and recovery techniques in optical networks
PublicationFailures in optical networks are inevitable. They may occur during work being done for the maintenance of other infrastructures, or on a larger scale as the result of an attack or large-scale disaster. As a result, service availability, an important aspect of Quality of Service (QoS), is often degraded. Appropriate fault recovery techniques are thus crucial to meet the requirements set by the Service Level Agreements (SLAs) between...
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Guided waves for monitoring of plate structures with linear cracks of variable length
PublicationDamage occurring at the work of plate structures may grow to a considerable size. The joint action – the detection of a defect at the earliest possible stage, the monitoring of its growth and the determination of its critical size in the context of structural reliability allows optimizing the cost of the maintenance and repair of structural elements. Thus the development of monitoring systems for permanent observation of fault...
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Recycling of raw materials, silicon wafers and complete solar cells from photovoltaic modules
PublicationPhotovoltaic modules (PVs) are an attractive way of generating electricity in reliable and maintenance-free systems with the use of solar energy. The average lifetime of photovoltaic modules is 25 to 30 years. To offset the negative impact of photovoltaic modules on the environment, it is necessary to introduce a long-term strategy that includes a complete lifecycle of all system components from the production phase through installation...
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Pre-feasibility study for treatment wetland application for wastewater treatment in dispersed development
PublicationThe aim of the paper is to present the conducted analyses of pre-feasibility study of different approaches for wastewater management in a settlement of 180 persons. In the assessment both technical and economic aspects were analyzed. The costs were calculated for three different and, at the same time, most popular as well as possible technical solutions like: (i) construction of local wastewater treatment plant with gravitational...
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A Triplet-Learnt Coarse-to-Fine Reranking for Vehicle Re-identification
PublicationVehicle re-identification refers to the task of matching the same query vehicle across non-overlapping cameras and diverse viewpoints. Research interest on the field emerged with intelligent transportation systems and the necessity for public security maintenance. Compared to person, vehicle re-identification is more intricate, facing the challenges of lower intra-class and higher inter-class similarities. Motivated by deep...
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A commercial of the shelf components for a unmanned air vehicle photogrammetry
PublicationA photogrammetry from a unmanned aerial vehicle (UAV) can be understood as a new measurement tool. Is introduces a low-cost alternatives for a traditional aerial photogrammetry. A commercial off-the-shelf products (COTS), that are commercially available for a costumers, are the standard manufactures products, not custom. COTS products are available in the commercial market and can be bought and used under government contract. That...
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Integrating web site services into application through user interface
PublicationThe issue of integrating applications which are only accessible through visual user interface is not thoroughly researched. Integration of web applications running remotely and controlled by separate organizations becomes even more complicated, as their user interface can display differently in different browsers or change without prior notification as a result of application maintenance. While possible, it is generally not common...
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New transition curve adapted to railway operational requirements
PublicationThe paper points to the limited possibilities of improving the existing situation in the area of transition curves used in geometrical layouts of the railway track. Difficulties in the practical implementation and maintenance of very small horizontal ordinates of the transition curve and the ordinates of the gradient due to cant in the initial section, appearing on smooth transition curves, were indicated. The main reason for this...
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THE CONCEPT OF MODELING OF SNOW IMPACT ON THE STRUCTURE OF THE SUSPENDED TAURON ARENA ROOF IN CRACOW
PublicationThe article presents studies and numerical simulations on modeling snow influence on TAURON ARENA suspended roof structure in Cracow. The scope of work includes experimental tests, functions solutions taking into account various cases of snow impact according to PN and EC, as well as numerical simulations for the sport and entertainment arena in the Czyzyny district. The FEM roof structure model developed in the SOFISITK software...
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Sodium nitrite as a corrosion inhibitor of copper in simulated cooling water
PublicationThe corrosion inhibition behavior of sodium nitrite (NaNO2) towards pure copper (99.95%) in simulated cooling water (SCW) was investigated by means of electrochemical impedance spectroscopy (EIS) and dynamic electrochemical impedance spectroscopy (DEIS). NaNO2 interferes with metal dissolution and reduce the corrosion rate through the formation or maintenance of inhibitive film on the metal surface. Surface morphologies illustrated...
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Automation of the Road Gate Operations Process at the Container Terminal—A Case Study of DCT Gdańsk SA
PublicationThe future increased terminal capacity will result in more container movement through the road complex and rail siding, which are one of the most critical areas (potential bottlenecks) in the container terminal. Truck turnaround time is one of the major factors that customers take into account while deciding how many container volumes they will handle through the container terminal. To enable to optimize increased traffic with...
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The literature review on boundary conditions of use for non-residential buildings
PublicationThis paper describes the results of qualitative and quantitative literature reviews on boundary conditions within educational buildings, emphasising the users' perspective. The reviews were performed before and during the COVID-19 pandemic using Scopus, Taylor& Francis, Web of Science databases. The boundary conditions understood as special characteristics for use and or precondition, determining specific features of buildings...
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The literature review on boundary conditions of use for non-residential buildings. Educational buildings.
PublicationThis paper describes the results of qualitative and quantitative literature reviews on boundary conditions within educational buildings, emphasising the users' perspective. The studies were performed before and during the COVID-19 pandemic using Scopus, Taylor& Francis, and Web of Science databases. The boundary conditions are understood as special characteristics for use and or precondition, determining specific features of...
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Determination of vertical displacements by using the hydrostatic levelling systems with the variable location of the reference sensor,
PublicationAbstract: In this paper, the author proposed a new method for determination of vertical displacements with the use of hydrostatic levelling systems. The traditional method of hydrostatic levelling uses a rule in which a position of reference sensor is stable. This assumption was not adapted in the proposed method. Regarding the issue mentioned above, the reference sensor is treated in the same way as the others sensors that measure...
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Sterowanie procesem eksploatacji okrętowych silników głównych z zastosowaniem diagnostyki technicznej
PublicationW referacie przedstawiono podstawowe uwarunkowania dotyczące możliwości zastosowania w praktyce eksploatacyjnej okrętowych układów energetycznych elementów strategii eksploatacji wg stanu technicznego (ang. Condition Based Maintenance). W tym aspekcie omówiono rolę diagnostyki jako narzędzia umożlwiającego podejmowanie racjonalnych, wynikających z aktualnego (lub prognozowanego) stanu technicznego, decyzji eksploatacyjnych oraz...
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Polymer journal bearings behaviour research under limited lubrication and cooling conditions conducted on high torque test rig
PublicationPolymer journal bearings are frequently used as a water-lubricated bearings of small marine units’ propeller shafts . Choice of these bearings is based on their simple construction and relatively low purchase and maintenance costs. Although properly designed and installed water lubricated bearings may well last for over a decade, rapid wear or failure of these bearings can be observed...
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Measurements of OF QoS/QoE parameters for media streaming in a PMIPv6 TESTBED WITH 802.11 b/g/n WLANs
PublicationA growing number of mobile devices and the increasing popularity of multimedia services result in a new challenge of providing mobility in access networks. The paper describes experimental research on media (audio and video) streaming in a mobile IEEE 802.11 b/g/n environment realizing network-based mobility. It is an approach to mobility that requires little or no modification of the mobile terminal. Assessment of relevant parameters...
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Evaluati on of long-term start up costs impact on short-term price based operational optimization of a CCGT using MILP
PublicationAn increasing share of the weather-dependent RES generation in the power system leads to the growing importance of flexibility of conventional power plants. They were usually designed for base load operation and it is a challenge to determine the actual long-term cycling costs, which account for an increase in maintenance and overhaul expenditures, increased forced outage rates and shortened life expectancy of the plant and components....
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Damage Imaging in Lamb Wave-Based Inspection of Adhesive Joints
PublicationAdhesive bonding has become increasingly important in many industries. Non-destructive inspection of adhesive joints is essential for the condition assessment and maintenance of a structure containing such joints. The aim of this paper was the experimental investigation of the damage identification of a single lap adhesive joint of metal plate-like structures. Nine joints with different defects in the form of partial debonding...
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Energy storage device based on flywheel, power converters and Simulink real-time
PublicationThis electronic document is a “live” template and already defines the components of your paper [title, text, heads, etc.] in its style sheet. Paper presents information on Energy Storage Device based on Flywheel and bi-directional IGBT Power Converters – designed for LINTE^2 laboratory owned by Gdansk University of Technology in Poland. Paper is divided into four sections. First section of the paper provides introductory information...
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The effects of vehicle restraint systems on road safety
PublicationKey to understanding the needs and tools of road infrastructure management for preventing run-off-road crashes or minimising their consequences, is to identify the hazads and sources of hazards caused by wrong or improper use of road safety devices and identify errors in the desifn, structure, construction and operation of road safety devices. Studying such an extended scope of the problem required fieldwork and surveys with road...
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Uwarunkowania diagnostyczne sterowania procesem eksploatacji okrętowych silników głównych
PublicationZe względu na losowość czynników wymuszających podczas użytkowania urządzeń okrętowych w praktyce eksploatacyjnej okrętowych układów energetycznych wdrażanych jest coraz więcej elementów strategii eksploatacji wg stanu technicznego (ang. Condition Based Maintenance). W referacie przedstawiono wybrane problemy dotyczące diagnostyki jako niezbędnego ogniwa w ciągu czynności związanych z podejmowaniem racjonalnych, podyktowanych...
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Development of Strategies for AOB and NOB Competition Supported by Mathematical Modeling in Terms of Successful Deammonification Implementation for Energy-Efficient WWTPs
PublicationNovel technologies such as partial nitritation (PN) and partial denitritation (PDN) could be combined with the anammox-based process in order to alleviate energy input. The former combination, also noted as deammonification, has been intensively studied in a frame of lab and full-scale wastewater treatment in order to optimize operational costs and process efficiency. For the deammonification process, key functional microbes include...
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Assessment of Adjustment of GNSS Railway Measurements with Parameter-Binding Conditions in a Stationary Scenario
PublicationThe study aims to assess the applicability of the ordinary least squares method, robust estimation, and conditions-binded adjustment in processing the six synchronous coordinate pairs of global navigation satellite system (GNSS) receivers. The research is part of the research project InnoSatTrack, focused on the enhancement of the determination of geometrical parameters of railway tracks using GNSS, inertial, and other sensors....
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Assessing the failure of Open Government Data initiatives in Brazil
PublicationWhile assessing the potential of a particular digital innovation initiative, especially when it has implications for a range of societal stakeholders, it becomes pertinent to understand the possible bottlenecks in its acceptability as well. In this regard, the present study seeks to understand how the Open Government Data (OGD) initiatives in Brazil are being confronted with bottlenecks in terms of their execution and acceptability....
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The conception of energetic investigations of the multisymptom fatigue of the simple mechanical systems' constructional materials
PublicationThe article presents the basic assumptions of the research project aimed, as the main scientific purpose, an identification of the slow-changeable energy processes surrounding the high-cycle fatigue of constructional materials within the plain mechanical system, especially the marine one, for diagnostic purposes. There is foreseen an application of alternative diagnostic methods based on energetic observations of the multi-symptom,...
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Towards automation of IT systems repairs
PublicationMonitoring and repair are two sides of the on-the-fly maintenance of IT systems.Monitoring is well supported by automatic tools. In contrast, repairs involve much higherhuman intervention which negatively affects reliability and efficiency. The paper intro-duces a method of automating repairs of IT systems which can be integrated with any ofthe existing monitoring mechanisms. The method is described as a collection of modelsand...
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Multitaper-Based Post-processing of Compact Antenna Responses Obtained in Non-anechoic Conditions
PublicationThe process of developing antenna structures typically involves prototype measurements. While accurate validation of far-field performance can be performed in dedicated facilities like anechoic chambers, high cost of construction and maintenance might not justify their use for teaching, or low-budget research scenarios. Non-anechoic experiments provide a cost-effective alternative, however the performance metrics obtained in such...
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Analiza wydajności kolektora słonecznego przeznaczonego dla systemu ogrzewania budynku o niskim zapotrzebowaniu na ciepło
PublicationNiniejsza praca przedstawia wyniki badań numerycznych kolektora słonecznego, przeznaczonego dla budynków o niskim zapotrzebowaniu na ciepło. W pracy przedstawiono nowatorską koncepcję kolektora słonecznego o obniżonej wydajności, niskich kosztach wykonania oraz wykorzystującego istniejące elementy konstrukcji przekryć budynku. Istotną zaletą kolektora jest brak ingerencji w architekturę zewnętrzną budynku. Za pomocą symulacji numerycznej...
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Protection of historical heritage as part of the development of cultural tourism – a case study of the community of Kamieniec Ząbkowicki in Lower Silesia
PublicationBoth literature and economics show a changing approach to historical heritage. It is no longer seen as a resource that generates only high maintenance costs. Analyses of local government units (LGUs) show that historical heritage is a strength rather than a weakness. More and more often, it is considered in economic development strategies as an asset that creates new activities and functions, generates income, and creates jobs....
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RESEARCH ON ORGANIC COATINGS DESIGNED FOR UNDERWATER APPLICATIONS
PublicationUnderwater steel structures require periodic maintenance. In the case of vessels, anti-corrosion works are carried out in the shipyard, where very good conditions for applying organic protective coatings can be provided. Very good surface preparation can be obtained by the use of abrasive blasting. The well-prepared metal surface is free from impurities (particularly inorganic salts). Suitable conditions for the application and...
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Removal of cyclohexane vapors from air in biotrickling filters: Effects of gas mixture composition and circular economy approach
PublicationThis work presents results of investigations on biotrickling filtration of air polluted with cyclohexane co-treated in binary, ternary and quaternary volatile organic compounds (VOCs) mixtures, including vapors of hexane, toluene and ethanol. The removal of cyclohexane from a gas mixture depends on the physicochemical properties of the co-treated VOCs and the lower the hydrophobicity of the VOC, the higher the removal efficiency...
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BINDER COURSES USING COLD RECYCLED MIXTURES – A NOVEL CONCEPT IN COLD RECYCLING
PublicationCold recycling with cement and bituminous emulsion is one of the most environmentally friendly techniques to maximize the reuse of reclaimed asphalt (RA) collected during demolition of roads. Cold recycled mixtures are commonly used for base courses in construction or rehabilitation of flexible and semi-rigid pavements. Current experiences demonstrated that cold recycling with appropriate requirements and technical recommendations...
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Preparatory Railway Track Geometry Estimation Based on GNSS and IMU Systems
PublicationThe article discusses an important issue of railway line construction and maintenance, which fundamentally is the verification of geometric parameters of the railway track. For this purpose, mobile measurements have been performed using a measuring platform with two properly arranged GNSS receivers, which made it possible to determine the base vector of the platform. The measuring functionality of the system was extended by IMU....
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Why Are Left-Handed G-Quadruplexes Scarce?
PublicationG-quadruplexes (G4s) are nucleic acid structures crucial for the regulation of gene expression and genome maintenance. While they hold promise as nanodevice components, achieving desired G4 folds requires understanding the interplay between stability and structural properties, like helicity. Although right-handed G4 structures dominate the experimental data, the molecular basis for this preference over left-handed helicity is unclear....
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Assessment of the Influence of Road Infrastructure Parameters on the Behaviour of Drivers and Pedestrians in Pedestrian Crossing Areas
PublicationPedestrians are participants and, most likely, fatalities in every third road traffic accident in Poland. Over 30% of all fatalities on Polish roads are pedestrians. Accidents with pedestrians are very often the result of various factors related to the infrastructure and behaviour of pedestrians and drivers. The objective of the work was to assess driver and pedestrian behaviour in pedestrian crossing areas. The research also served...
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DOP and Pseudorange Error Estimation in Mobile GNSS Systems for Android OS Applications
PublicationIn the near past, GNSS (Global Navigation Satellite Systems) were only offered for a narrow group of recipients. Nowadays, thanks to mobile devices, they are available to anyone and everywhere. Personal navigation, searching for POI (Point of Interest), etc., had become a basic essential activity. Thanks to the widespread and availability of smartphones each user can obtain information considering his or her location even in an...
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DOP and Pseudorange Error Estimation in Urban Environments for Mobile Android GNSS Applications
PublicationJust a couple of years ago, GNSS (Global Navigation Satellite Systems) were available only for a narrow group of users. Currently, with the outbreak of mobile devices, they are accessible to anyone and everywhere. Urban navigation or searching for POIs (Points of Interest) had become an everyday activity. With the availability of consumer electronics and wireless technologies, each user can obtain information considering his or...
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Potentiometric Oxygen Sensor with Solid State Reference Electrode
PublicationThe concentration or the partial pressure of oxygen in an environment can be determined using different measuring principles. For high temperature measurements of oxygen, ceramic-based sensors are the most practical. They are simple in construction, exploration and maintenance. A typical oxygen potentiometric sensor consists of an oxygen ion conducting solid electrolyte and two electrodes deposited...
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Innovative system for energy collection and management integrated within a photovoltaic module
PublicationThe dynamic development of battery technology and design based on the flow of lithium ions, mainly driven by the needs of the automotive industry, leads to the conclusion that these batteries are becoming a more viable alternative to traditional lead-acid batteries. Their use is driven by the ability to quickly charge and discharge, a higher durability, maintenance-free operation, much smaller dimensions and lighter weight. The...
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Wpływ przechyłki na zjawisko postępowania zużycia bocznego szyn kolejowych w łukach poziomych
PublicationDegradacja elementów nawierzchni kolejowej jest zagadnieniem bardzo złożonym, w które uwikłane jest wiele czynników związanych między innymi z układem geometrycznym toru kolejowego, właściwościami trybologicznymi poszczególnych elementów nawierzchni, jak również z parametrami podłoża gruntowego, a także z właściwościami samych pojazdów szynowych. W artykule omówiono jeden z powyższych problemów, tj. wpływ ukształtowania toru kolejowego...
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Evaluation of the Possibility of Identifying a Complex Polygonal Tram Track Layout Using Multiple Satellite Measurements
PublicationWe present the main assumptions about the algorithmization of the analysis of measurement data recorded in mobile satellite measurements. The research team from the Gda´nsk University of Technology and the Maritime University in Gdynia, as part of a research project conducted in cooperation with PKP PLK (Polish Railway Infrastructure Manager), developed algorithms supporting the identification and assessment of track axis layout....
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Factors affecting low-temperature cracking of asphalt pavements: analysis of field observations using the ordered logistic model
PublicationAccurate identification of factors that primarily affect the number of low-temperature cracks is crucial for selection of road materials and planning of pavement maintenance. Field investigations of lowtemperature cracks were performed in the years 2014 and 2020 on the same 68 road sections being in service in typical traffic conditions. The collected data were statistically analysed using the ordered logistic regression model....
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Small regulatory bacterial RNAs regulating the envelope stress response
PublicationMost bacteria encode a large repertoire of RNA-based regulatory mechanisms. Recent discoveries have revealed that the expression of many genes is controlled by a plethora of base-pairing noncoding small regulatory RNAs (sRNAs), regulatory RNA-binding proteins and RNA-degrading enzymes. Some of these RNA-based regulated processes respond to stress conditions and are involved in the maintenance of cellular homeostasis. They achieve...
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A novel dual-band rectifier circuit with enhanced bandwidth for RF energy harvesting applications
PublicationIn recent years, a rapid development of low-power sensor networks, enabling machine-to-machine communication in applications such as environmental monitoring, has been observed. Contemporary sensors are normally supplied by an external power source, typically in a form of a battery, which limits their lifespan and increases the maintenance costs. This problem can be addressed by harvesting and converting ambient RF energy into...
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Suppressors of lapC mutation identify new regulators of LpxC, which mediates the first committed step in lipopolysaccharide biosynthesis
PublicationGram-negative bacteria, such as Escherichia coli, are characterized by an asymmetric outer membrane (OM) with lipopolysaccharide (LPS) located in the outer leaflet and phospholipids facing the inner leaflet. E. coli recruits LPS assembly proteins LapB, LapC and LapD in concert with FtsH protease to ensure a balanced biosynthesis of LPS and phospholipids. We recently reported that bacteria either lacking the periplasmic domain of...
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Molecular dynamics simulations reveal the balance of forces governing the formation of a guanine tetrad—a common structural unit of G-quadruplex DNA
PublicationG-quadruplexes (G4) are nucleic acid conformations of guanine-rich sequences, in which guanines are arranged in the square-planar G-tetrads, stacked on one another. G4 motifs form in vivo and are implicated in regulation of such processes as gene expression and chromosome maintenance. The structure and stability of various G4 topologies were determined experimentally; however, the driving forces for their formation are not fully...
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Evaluation of the Possibility of Identifying a Complex Polygonal Tram Track Layout Using Multiple Satellite Measurements
PublicationWe present the main assumptions about the algorithmization of the analysis of measurement data recorded in mobile satellite measurements. The research team from the Gda´nsk University of Technology and the Maritime University in Gdynia, as part of a research project conducted in cooperation with PKP PLK (Polish Railway Infrastructure Manager), developed algorithms supporting the identification and assessment of track axis layout....
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Bezzałogowe środki latające (BSL) w układzie czterowirnikowego helikoptera
PublicationRozwój układów sterowania, kamer pracujących w świetle widzialnym oraz w podczerwieni doprowadził do wzrostu znaczenia bezpilotowych środków latających. Bezpilotowe środki latające wykorzystywane są do realizacji celów zarówno wojskowych, jak i cywilnych. Podstawowymi zaletami bezpilotowych środków latających są: małe wymiary, duża mobilność, niskie koszty wytworzenia i eksploatacji. Użytkowanie bezpilotowych środków latających...