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Search results for: riemannian manifold · hestenes operator · smooth decomposition of identity · wavelet frame · triebel-lizorkin space
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Re-thinking the city in the context of suburban landscapes. The case of Visula River delta water - landscapes and urban transformation processes in Gdańsk
PublicationThe text draws attention to the significant role of landscape formations surrounding the city and their role in marking out directions for the transformation and development of urban areas with the particular emphasis on public spaces. The article presents the need for a more conscious design strategies that are based on connectedness of urban spaces, which is built on landscape's characteristics, as an essential starting point...
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A Method of Object Re-identiciation Applicable to Multicamera Surveillance Systems
PublicationThe paper addresses some challenges pertaining to the methods for tracking of objects in multi-camera systems. The tracking methods related to a single Field of Vision (FOV) are quite different from inter-camera tracking, especially in case of non-overlapping FOVs. In this case, the processing is directed to determine the probability of a particular object’s identity seen in a pair of cameras in the presence of places non-observed...
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Effect of Maximal Apnoea Easy-Going and Struggle Phases on Subarachnoid Width and Pial Artery Pulsation in Elite Breath-Hold Divers
PublicationPurpose: The aim of the study was to assess changes in subarachnoid space width (sas-TQ), the marker of intracranial pressure (ICP), pial artery pulsation (cc-TQ) and cardiac contribution to blood pressure (BP), cerebral blood flow velocity (CBFV) and cc-TQ oscillations throughout the maximal breath hold in elite apnoea divers. Non-invasive assessment of sas-TQ and cc-TQ became possible due to recently developed method based on...
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AN ORIGINAL APPROACH IN THE FIELD OF PREPARATION REFERENCE MATERIALS OF VOLATILE ANALYTES
PublicationStandard gas mixtures (SGM) are indispensable reference materials for ensuring the reliability of analytical work. Reference materials are an excellent tool for the quality control and assurance of analytical results. Standard gas mixtures are unique among reference materials. The rapid progress of SGM production is connected with the instability of gaseous analytes which make them difficult to obtain. The use of standards with...
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The complexity of minimum-length path decompositions
PublicationWe consider a bi-criteria generalization of the pathwidth problem, where, for given integers k, l and a graph G, we ask whether there exists a path decomposition P of G such that the width of P is at most k and the number of bags in P, i.e., the length of P, is at most l. We provide a complete complexity classification of the problem in terms of k and l for general graphs. Contrary to the original pathwidth problem, which is fixed-parameter...
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Ridging, strength, and stability in high-resolution sea ice models
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Large‐Scale Traveling Ionospheric Disturbances Over the European Sector During the Geomagnetic Storm on March 23–24, 2023: Energy Deposition in the Source Regions and the Propagation Characteristics
PublicationMultiple Large-Scale Traveling Ionospheric Disturbances (LSTIDs) are observed in the European sector in both day-time and night-time during the magnetic storm on March 23–24, 2023. The Total Electron Content (TEC) observation from a network of GNSS receivers shows the propagation of LSTIDs with amplitudes between around 0.5 and 1 TECU originating from auroral and polar cusp regions down to southern Europe (35°N) with velocities...
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Lamb wave-based monitoring of shear failure of an adhesive lap joint
PublicationThe paper presents a study on the elastic wave propagation in adhesive joints of steel plates subjected to tensile loading. A single lap joint was chosen for analysis because of its simplicity and plurality of applications. Experimental investigations consisted of the uniaxial extension of prepared specimens. Force and displacement values were recorded by a testing machine. Simultaneously, guided Lamb waves were excited and signals...
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Analyzing the Effectiveness of the Brain–Computer Interface for Task Discerning Based on Machine Learning
PublicationThe aim of the study is to compare electroencephalographic (EEG) signal feature extraction methods in the context of the effectiveness of the classification of brain activities. For classification, electroencephalographic signals were obtained using an EEG device from 17 subjects in three mental states (relaxation, excitation, and solving logical task). Blind source separation employing independent component analysis (ICA) was...
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SIMPLIFIED DYNAMIC MODEL OF ROTATING BEAM
PublicationIn the paper a hybrid model of rotating beam is presented. It was obtained by using two methods: modal decomposition and spatial discretization. Reduced modal model was built for the system without the load related to inertia forces that occur during beam rotation. This inertia load was next modeled by using the method of simply spatial discretization and combined with reduced modal model. This approach allows to obtain accurate...
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New developments in preparation and use of standard gas mixtures
PublicationStandard gas mixtures are commonly applied in all stages of analytical work related to the analysis of gaseous samples. Numerous techniques for generating standard gas mixtures are in use. In this article, we present new developments regarding the production of standard gas mixtures, with particular focus on improvements in the application of dynamic techniques for generating them. Furthermore, we describe the application of new...
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Numerical conditioning of delta-domain Lyapunov and Riccati equations
PublicationW pracy rozważono problem uwarunkowania dyskretno czasowych równań Lapunowa oraz równań Riccatiego - to znaczy problem wrażliwości rozwiązań takich równań na odchyłki ich parametrów od nominalnych wartości. Zdefiniowano odpowiedni "różniczkowy" wskaźnik uwarunkowania oraz podano efektywną metodę szacowania jego wartości. Udowodniono teoretycznie - a także przekonująco zilustrowano na drodze numerycznej - twierdzenie głoszące, iż...
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A derivatisation agent selection guide
PublicationThe development of new tools for providing high quality information in a cost-effective and expeditious way is one of the main aims of analytical chemistry. Remarkably, the introduc- tion of the 12 principles of green chemistry paved the way forward for the development of analytical methodologies that are, ideally, inherently safe for the operator and the environ- ment, with the least possible consumption of energy and chemicals,...
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Cele, koncepcja i założenia Krajowego Systemu Zarządzania Ruchem
PublicationW pracy przedstawiono historię prac zmierzających do opracowania jednolitego standardu FRAME. Opisano założenia i cele Krajowego Systemu Zarządzania Ruchem. Przedstawiono 17 modułów wdrożeniowych, które będą wdrażane na drogach sieci TEN-T, sieci dróg krajowych nie należących do tej sieci i na nowo - budowanych odcinkach dróg, w zakresie kontraktów budowlanych. W artykule przedstawiono obszary funkcjonalne KSZR i bazy danych, które...
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Distinctive properties of Scots pine (Pinus sylvestris L.) originating from the Carpathian and Great Poland-Pomeranian of Nature and Forest Land
PublicationIn this paper values of properties of Scots pine, the fracture toughness and of shear yield stress in the shear zone are presented. Samples of Scotch pine (Pinus sylvestris L.) wood of two provenances from Poland were tested. These properties were determined from the values of cutting power obtained experimentally on the saw frame PRW-15M. The values of fracture toughness and shear yield stress based on the Atkins model for cutting...
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Evidence-Based Risk Management for Civil Engineering Projects Using Bayesian Belief Networks (BBN)
PublicationThe authors are seeking new methods for improving the efficiency of the investments associated with the maintenance and operation of existing civil engineering structures. It is demonstrated how the knowledge about the elements of construction and operation phases and their relationships, combined with monitoring data can be used for more effective management of the risks associated with civil engineering projects. The methodology...
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A Model for Risk Assessment and Management of Construction Projects in Urban Conditions
PublicationThe authors are seeking new methods for improving the efficiency of the investments associated with the maintenance and operation of existing civil engineering structures. It is demonstrated how the knowledge about the elements of construction and operation phases and their relationships, combined with monitoring data can be used for more effective management of the risks associated with civil engineering projects. The methodology...
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Hałaśliwość silników asynchronicznych – podstawy nowych hipotez
PublicationArtykuł zawiera nowe spojrzenie na hałas emitowany przez silniki asynchroniczne. Poprzez wykonane badania akustyczne z analizami widmowymi określono związki przyczynowo-skutkowe powstawania drgań i hałasu przy zasilaniu sieciowymch i przekształtnikowym. Na podstawie wyznaczonych charakterystyk kierunkowych ciśnienia akustycznego silników sformułowano hipotezę, że rola tarcz łożyskowych w emitowaniu hałasu przez silnik może być...
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On Reduced-Cost Design-Oriented Constrained Surrogate Modeling of Antenna Structures
PublicationDesign of contemporary antenna structures heavily relies on full-wave electromagnetic (EM) simulation models. Such models are essential to ensure reliability of evaluating antenna characteristics, yet, they are computationally expensive and therefore unsuitable for handling tasks that require multiple analyses, e.g., parametric optimization. The cost issue can be alleviated by using fast surrogate models. Conventional data-driven...
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The potential of web awareness as a determinant of dually defined customer value
PublicationIn the conditions of increasing demand barrier, the enterprise’s basic capital is customers. From an enterprise point of view, this means the need to create a dual perceived and defined customer value which remains related to market value (income and development potential) and customer resource value (reference, information and cooperative potential). The progressing digitisation process transfers business processes, and thus relationships, into...
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Joint fingerprinting and decryption method for color images based on quaternion rotation with cipher quaternion chaining
PublicationThis paper addresses the problem of unauthorized redistribution of multimedia content by malicious users (pirates). In this method three color channels of the image are considered a 3D space and each component of the image is represented as a point in this 3D space. The distribution side uses a symmetric cipher to encrypt perceptually essential components of the image with the encryption key and then sends the encrypted data via...
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Assessment of Alterations in Settlement Patterns of Agricultural Landscape in the Example of Kashubia in Poland
PublicationTraditional agricultural landscapes are heavily exposed to change due to their relatively low agricultural productivity. However, they represent cultural values of great importance in maintaining the resilience of the environment and society. Although their cultural potential is important for sustainable development, it is still insufficiently recognized. The article fills this gap by examining old farmstead buildings as a distinguishing...
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Quantum entanglement in time
PublicationIn this paper we present a concept of quantum entanglement in time in a context of entangled consistent histories. These considerations are supported by presentation of necessary tools closely related to those acting on a space of spatial multipartite quantum states. We show that in similarity to monogamy of quantum entanglement in space, quantum entanglement in time is also endowed with this property for a particular history....
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Characterization of a cryptic plasmid pSFKW33 from Shewanella sp. 33b
PublicationA cryptic plasmid pSFKW33 from psychrotrophic bacterium Shewanella sp. 33B, an isolate from the Gulf of Gdansk (the Baltic Sea), was sequenced and characterized. It is an 8021 bpcircular molecule with 38% GC content, which shows a distinctive nucleotide sequence without homology to other known plasmids. The nucleotide sequence analysis predicts eight open reading frames. The deduced amino acid sequence of ORF-1 shared significant...
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Characterization of a single-stranded DNA-binding-like Protein from Nanoarchaeum equitans - a nucleic acid binding protein with broad substrate specificity
PublicationBackground SSB (single-stranded DNA-binding) proteins play an essential role in all living cells and viruses, as they are involved in processes connected with ssDNA metabolism. There has recently been an increasing interest in SSBs, since they can be applied in molecular biology techniques and analytical methods. Nanoarchaeum equitans, the only known representative of Archaea phylum Nanoarchaeota, is a hyperthermophilic, nanosized,...
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Characterization of two aminotransferases from Candida albicans
PublicationAminoadipate aminotransferase (AmAA) is an enzyme of α-aminoadipate pathway (AAP) for l-lysine biosynthesis. AmAA may also participated in biosynthesis or degradation of aromatic amino acids and in d-tryptophan based pigment production. The AAP is unique for fungal microorganisms. Enzymes involved in this pathway have specific structures and properties. These features can be used as potential molecular markers. Enzymes catalyzing...
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Geodesy measurement techniques as an enrichment of archaeological research workflow
PublicationUse of geodesy techniques is widespread in different fields of science. Especially in such an emerging and dynamic branch of science as archaeology. Warsaw Institute of Archaeology, conducts many archaeological expeditions, among the others Polish-Georgian archaeological expedition in Gonio, where ancient Roman Bath has been discovered and excavated. Gonio is located in Adjara, Georgia, placed on the Black Sea coast. Fortress...
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Synthesis and characterisation of polyurethane elastomers with semi-products obtained from polyurethane recycling
PublicationIn this work polyurethane elastomers were synthesised by using different mixtures of a petrochemical and glycerolysate polyols and 4,4-diphenylmethane diisocyanate (MDI). Glycerolysate polyol was produced from polyurethane foam decomposition using crude glycerine as a decomposition agent. The structure and thermal properties of obtained semi-product were similar to the polyol used in the synthesis of original foam. Glycerolysate...
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Studies on novel BiyXz-TiO2/SrTiO3 composites: Surface properties and visible light-driven photoactivity
PublicationA series of novel BiyXz-TiO2/SrTiO3 composites were prepared by multistep synthesis route. The asprepared photocatalysts were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), diffuse reflectance spectroscopy (DRS), Fourier transform infrared (FT-IR), Raman spectra and BET analysis. The photocatalytic activity test was performed in aqueous solution of phenol under...
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Photocatalytic and Antimicrobial Properties of Ag2O/TiO2 Heterojunction
PublicationAg2O/TiO2 heterojunctions were prepared by a simple method, i.e., the grinding of argentous oxide with six different titania photocatalysts. The physicochemical properties of the obtained photocatalysts were characterized by diffuse-reflectance spectroscopy (DRS), X-ray powder diffraction (XRD) and scanning transmission electron microscopy (STEM) with an energy dispersive X-ray spectroscopy (EDS). The photocatalytic activity was...
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Analiza niezawodności człowieka z uwzględnieniem aspektów zarządzania alarmami
PublicationW artykule przedstawiono zagadnienie analizy warstwowego systemu zabezpieczeń z uwzględnieniem błędu człowieka-operatora. W analizie bezpieczeństwa funkcjonalnego systemów sterowania i zabezpieczeń istotną kwestią jest dokonanie redukcji ryzyka poprzez warstwy zabezpieczeniowo ochronne. W referacie przeanalizowano system składający się z trzech warstw: podstawowego systemu sterowania BPCS, systemu alarmowego AS oraz systemu automatyki...
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Cognitive engineering and functional safety technology for reducing risks in hazardous plants
PublicationCognitive engineering is considered nowadays as interesting multidisciplinary domain that focuses on improving the relations between humans and the systems that are supervised and operated. The industrial automation and control systems (IACS) in hazardous plants are increasingly computerized and perform various safety functions. These are designed and implemented according to the functional safety concept. The objective is to maintain...
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The control software of the portable raman spectrometer
PublicationThe paper contains a description of the control software of a portable Raman spectrometer which was built in the Department of Optoelectronics and Electronic Systems Faculty of Electronics, Telecommunications and Informatics Gdansk University of Technology. The software has modular structure, which includes the laser control module and the spectrum acquisition module (laser power selection, working mode and data acquisition time)...
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Protection and renovation of public areas in a modernist city: the case of three streets in the historic City Centre of Gdynia
PublicationThis article concerns issues related to the preservation and restoration of public space in Gdynia’s city centre, which was designed and built mainly in the 1920s and 1930s. In 2007, a major part of the city centre was entered into the register of monuments asa historic complex of urban architecture. Moreover, in 2015, the area was declared a Monument of History. Protection of a complex of urban architecture covers not only the...
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The impact of surface slope and calculation resolution on the fractal dimension for fractures of steels after bending-torsion fatigue
PublicationThe article presents the results of the fractal dimension measurements on the fatigue fracture surfaces of 10HNAP and S355J2 steels specimens after combined bending-torsion fatigue. For smooth and ring-notched specimens, three loading conditions were analyzed: (1) bending; (2) bending-torsion; and (3) torsion fatigue. Post-failure surface topography measurements were carried out on the entire fracture surfaces using an optical...
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Computer System for Evaluation of Shock Hazard in Circuits with Non-sinusoidal Earth Currents
PublicationEffects of current on people are mainly considered for 50/60 Hz sinusoidal current and smooth direct current. However, modern low voltage circuits are very often equipped with power electronics converters – rectifiers, frequency converters, therefore non-sinusoidal earth currents (touch currents) occur. For non-sinusoidal currents safety criteria should be modified. This paper presents a computer system, based on LabVIEW environment,...
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On modelling and non-linear elasto-plastic analysis of thin shells with deformable junctions
PublicationThe undeformed base surface of the irregular thin shell is modelled by the union of a finite number of regular smooth surface elements joined together along spatial curvilinear surface edges. The equilibrium conditions are formulated by postulating an appropriate form of the principle of virtual work, where also deformability of shell junctions is taken into account. The PVW is then discretised by C1 finite elements and the incremental-iterative...
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Benchmarking Scalability and Security Configuration Impact for A Distributed Sensors-Server IOT Use Case
PublicationInternet of Things has been getting more and more attention and found numerous practical applications. Especially important in this context are performance, security and ability to cope with failures. Especially crucial is to find good trade-off between these. In this article we present results of practical tests with multiple clients representing sensors sending notifications to an IoT middleware – DeviceHive. We investigate performance...
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Decisional DNA based framework for representing Virtual Engineering Objects
PublicationIn this paper, we propose a frame-work to represent the Virtual Engineering Objects (VEO) utilizing Set of Knowledge Experience Structure (SOEKS) and Decisional DNA. A VEO will enable the discovery of new knowledge in a manufacturing unit and the generation of new rules that drive reasoning. The proposed VEO framework will not only be knowledge based representation but it will also have its associated experience embedded within...
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Monitoring of underdeck corrosion by using acoustic emission method
PublicationThis paper presents first short characteristics of underdeck corrosion process as well as a problem of its monitoring. Next is described an acoustic emission (AE) method elaborated by Department of Ship Technology , Quality Systems and Material Engineering, Gdańsk University of Technology in cooperation with partners of CORFAT project realized within 7th EU Frame Program . Further are presented short characteristics of the emission...
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Functional safety and human factors
PublicationRozdział przedstawia istotny problem uwzględnienia czynników ludzkich (H&OF) w analizie bezpieczeństwa funkcjonalnego, które wpływają istotnie na bezpieczeństwo przemysłowych obiektów podwyższonego ryzyka, nie ujęty jednak w normach bezpieczeństwa funkcjonalnego. Przedstawia się metody analizy niezawodności człowieka (HRA) w kontekście tych czynników, które wpływają na błędy człowieka. Czynniki ludzkie i organizacyjne powinny być...
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Influence of Fluid Compressibility and Movements of the Swash Plate Axis of Rotation on the Volumetric Efficiency of Axial Piston Pumps
PublicationThis paper describes the design of a swash plate axial piston pump and the theoretical models describing the bulk modulus of aerated and non-aerated fluids. The dead space volume is defined and the influence of this volume and the fluid compressibility on the volumetric efficiency of the pump is considered. A displacement of the swash plate rotation axis is proposed to reduce the dead space volume for small swash plate swing angles....
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Landscape as the tool of coherence in the land management of rural communes
PublicationEconomic and social transformation of rural areas in Poland after 1990 reveals itself through disintegration of previous spatial order. Building a new pattern requires a vision, which would counteract complex causes of disintegration. The latter belong to institutional domain of planning strategies and the area of common practices. Therefore, agreement on aims and means between spatial policy strategies and tactics of space users...
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City walk: a didactic innovative experiment in architectural education
PublicationWalking is an activity that involves studying physical space and requires careful observation to be immersed in the surrounding reality. City walks are popular ways of encountering an urban space, spatial relation, its history, and recognising the problems and needs of space users, as well as future development of the city. City walks also may be educationally p owerful: the exploration of certain...
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Expedited Multi-Objective Design Optimization of Miniaturized Microwave Structures Using Physics-Based Surrogates
PublicationIn this paper, a methodology for fast multi-objective design optimization of compact microwave circuits is presented. Our approach exploits an equivalent circuit model of the structure under consideration, corrected through implicit and frequency space mapping, then optimized by a multi-objective evolutionary algorithm. The correction/optimization of the surrogate is iterated by design space confinement and segmentation based on...
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Employees’ self-expansion as a mediator between perceived work conditions and work engagement and productive behaviors
PublicationThere has been increasing scientific interest in the relationships between self-perception and group identity development processes as well as the behavioural implications of these processes in organizational contexts. Recently, the concept of workplace self-expansion has been introduced to work and organizational psychology. That is, the self-expanding characteristics of work and the workplace have been related to job satisfaction...
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The dynamic signature verification using population-based vertical partitioning
PublicationThe dynamic signature is an attribute used in behavioral biometrics for verifying the identity of an individual. This attribute, apart from the shape of the signature, also contains information about the dynamics of the signing process described by the signals which tend to change over time. It is possible to process those signals in order to obtain descriptors of the signature characteristic of an individual user. One of the methods...
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Evolutionary Algorithm for Selecting Dynamic Signatures Partitioning Approach
PublicationIn the verification of identity, the aim is to increase effectiveness and reduce involvement of verified users. A good compromise between these issues is ensured by dynamic signature verification. The dynamic signature is represented by signals describing the position of the stylus in time. They can be used to determine the velocity or acceleration signal. Values of these signals can be analyzed, interpreted, selected, and compared....
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Generalized access control in hierarchical computer network
PublicationThe paper presents the design of the security layer for a distributed system located in the multizone hierarchical computer network. Depending on the zone from which a client’s request comes to the system and the type of the request, it will be either authorized or rejected. There is one common layer for the access to all the business services and interactions between them. Unlike the commonly used RBAC model, this system enforces...
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Residual MobileNets
PublicationAs modern convolutional neural networks become increasingly deeper, they also become slower and require high computational resources beyond the capabilities of many mobile and embedded platforms. To address this challenge, much of the recent research has focused on reducing the model size and computational complexity. In this paper, we propose a novel residual depth-separable convolution block, which is an improvement of the basic...