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Design thinking (DT) for the design and planning education of engineer-architects
PublicationEngineers are facing new challenges connected with globalisation, digitisation and the increased complexity of the design process. This calls for new, more interdisciplinary and user-oriented approaches to problem- solving. In this article, the authors analyse design thinking (DT) as a method to support the education of engineers specialising in architecture and urban planning. Identified in this study are the opportunities this...
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Emotion Recognition Using Physiological Signals
PublicationIn this paper the problem of emotion recognition using physiological signals is presented. Firstly the problems with acquisition of physiological signals related to specific human emotions are described. It is not a trivial problem to elicit real emotions and to choose stimuli that always, and for all people, elicit the same emotion. Also different kinds of physiological signals for emotion recognition are considered. A set of...
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Mechanism of Solute and Thermal Characteristics in a Casson Hybrid Nanofluid Based with Ethylene Glycol Influenced by Soret and Dufour Effects
PublicationThis article models a system of partial differential equations (PDEs) for the thermal and solute characteristics under gradients (concentration and temperature) in the magnetohydrodynamic flow of Casson liquid in a Darcy porous medium. The modelled problems are highly non-linear with convective boundary conditions. These problems are solved numerically with a finite element approach under a tolerance of 10−8. A numerical algorithm...
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Fortifications of Hel Peninsula in Poland – history, preservation and contemporary adaptation.
PublicationThe Hel Peninsula fortifications are one of the largest and most interesting historic coastal fortification complexes in Poland. Built from the 1930s until demilitarisation at the end of the Cold War, they are now one of the biggest tourist attractions of the region. The article attempts to describe the history of their development, current state and selected problems related to their protection and adaptation for touristic purposes....
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Fast Multi-Objective Aerodynamic Optimization Using Sequential Domain Patching and Multifidelity Models
PublicationExploration of design tradeoffs for aerodynamic surfaces requires solving of multi-objective optimization (MOO) problems. The major bottleneck here is the time-consuming evaluations of the computational fluid dynamics (CFD) model used to capture the nonlinear physics involved in designing aerodynamic surfaces. This, in conjunction with a large number of simulations necessary to yield a set of designs representing the best possible...
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Scoreboard Architectural Pattern and Integration of Emotion Recognition Results
PublicationThis paper proposes a new design pattern, named Scoreboard , dedicated for applications solving complex, multi-stage, non-deterministic problems. The pattern provides a computational framework for the design and implementation of systems that integrate a large number of diverse specialized modules that may vary in accuracy, solution level, and modality. The Scoreboard is an extension of Blackboard design pattern and comes under...
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Thermal ablation modeling via bioheat equation
PublicationWe consider Pennes’ bioheat equation and discuss an implicit numerical scheme which has better stability properties than other approaches. Our discussion concerns Carthesian geometry problems, however it carries over to spherical geometry models and more complicated shapes.
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Security Mechanisms in the Comcute System
PublicationThe aim of this paper is pointing out the basic security problems and mechanisms in the Comcute system - maintenance system of large computing power in the face of critical crisis. Moreover security mechanism and tools useful to apply in laboratory model as well as target version of the Comcute system are presented.
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Successive Iterative Method for Higher-Order Fractional Differential Equations Involving Stieltjes Integral Boundary Conditions
PublicationIn this paper, the existence of positive solutions to fractional differential equations with delayed arguments and Stieltjes integral boundary conditions is discussed. The convergence of successive iterative method of solving such problems is investigated. This allows us to improve some recent works. Some numerical examples illustrate the results.
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Problemy planowania strategii i zagospodarowania przestrzennego w zarządzaniu rozwojem obszarów metropolitalnych
PublicationCelem pracy jest rozpoznanie i usystematyzowanie problemów związanych z planowaniem kompleksowej strategii zarządzania rozwojem obszarów metropolitalnych i sporządzaniem planu zagospodarowania przestrzennego tych obszarów. Problemy planowania rozumiane są jako trudności, dylematy i wątpliwości związane z różnymi aspektami procesu planistycznego. Autor nawiązuje do cech obszarów metropolitalnych oraz typowych problemów rozwiązywanych...
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Solution of coupled integral equations for quantum scattering in the presence of complex potentials
PublicationIn this paper, we present a method to compute solutions of coupled integral equations for quantum scattering problems in the presence of a complex potential. We show how the elastic and absorption cross sections can be obtained from the numerical solution of these equations in the asymptotic region at large radial distances.
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Numerical Simulation of two dimensional flow past a bridge cross section
PublicationThis work presents some numerical results concerning application of CFD in civil engineering problems. Selected theoretical aspects of fluid mechanics are elucidated. In the second part of the paper a cross section of upper footbridge of the Bella Sky Hotel in Copenhagen is analysed numerically in the field of wind action.
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Proximal primal–dual best approximation algorithm with memory
PublicationWe propose a new modified primal–dual proximal best approximation method for solving convex not necessarily differentiable optimization problems. The novelty of the method relies on introducing memory by taking into account iterates computed in previous steps in the formulas defining current iterate. To this end we consider projections onto intersections of halfspaces generated on the basis of the current as well as the previous...
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Towards systemic functional safety and security management in hazardous plants
PublicationThe aim of this article is to identify and discuss some issues related to functional safety and security management in hazardous industrial plants. The safety functions are to be realised using the electric / electronic / programmable electronic systems (E/E/PESs) or the safety instrumented systems (SISs) that are designed and operated respectively according to IEC 61508 and IEC 61511 requirements in life cycle. Although the role...
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Obtaining a Well-Trained Artificial Intelligence Algorithm from Cross-Validation in Endoscopy
PublicationThe article shortly discusses endoscopic video analysis problems and artificial intelligence algorithms supporting it. The most common method of efficiency testing of these algorithms is to perform intensive cross-validation. This allows for accurately evaluate their performance of generalization. One of the main problems of this procedure is that there is no simple and universal way of obtaining a specific instance of a well-trained...
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Evolutionary algorithm and decisional DNA for multiple travelling salesman problem
PublicationIn the real world, it is common to face optimization problems that have two or more objectives that must be optimized at the same time, that are typically explained in different units, and are in conflict with one another. This paper presents a hybrid structure that combines set of experience knowledge structures (SOEKS) and evolutionary algorithms, NSGA-II (Non-dominated Sorting Genetic Algorithm II), to solve multiple optimization...
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Scenarios in the development strategies of larger cities in Poland
PublicationSummary: Planning prepares decisions and future actions. Therefore, future conditions should be considered in planning, in particular strategic planning, due to its long-term nature. To accomplish this, certain prognostic methods should be applied. A scenario method is seen as one of the most useful prognostic method, especially in cases when social and institutional behaviour plays a crucial role. The aim of the paper is an analysis...
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A Finite Element Approach for Wave Propagation in Elastic Solids
PublicationThis book focuses on wave propagation phenomena in elastic solids modelled by the use of the finite element method. Although the latter is a well-established and popular numerical tool used by engineers and researchers all around the word the process of modelling of wave propagation can still be a challenge. The book introduces a reader to the problem by presenting a historical background and offering a broad perspective on the...
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Recent Issues and Challenges in the Study of Inland Waters
PublicationThis paper addresses several important problems and methods related to studies of inland waters based on the existing scientific literature. The use of UAVs in freshwater monitoring is described, including recent contact and non-contact solutions. Due to a decline in biological diversity in many parts of the globe, the main threats are described together with a modern method for algae and cyanobacteria monitoring utilizing chlorophyll...
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A simple and efficient hybrid discretization approach to alleviate membrane locking in isogeometric thin shells
PublicationThis work presents a new hybrid discretization approach to alleviate membrane locking in isogeometric finite element formulations for Kirchhoff–Love shells. The approach is simple, and requires no additional dofs and no static condensation. It does not increase the bandwidth of the tangent matrix and is effective for both linear and nonlinear problems. It combines isogeometric surface discretizations with classical Lagrange-based...
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SHORT REVIEW AND 3-D FEM ANALYSIS OF BASIC TYPES OF FOUNDATION FOR OFFSHORE WIND TURBINES
PublicationSome problems of the foundations of offshore wind turbines are considered in this paper. A short review is presented on the two basic types of foundations, i.e. monopiles and gravity foundations, including their basic features and applications as well as general design considerations. Also, some issues regarding analysis are discussed, including geotechnical problems and modelling techniques. A numerical model of offshores turbine...
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IMPROVING THE QUALITY OF EDUCATION THROUGH THE IMPLEMENTATION OF THE DIPLOMAS AND GROUP PROJECTS DURING ENGINEERING STUDIES IN COOPERATION WITH EMPLOYERS
PublicationThe quality of education is one of the most important factors determining the job opportunity for graduates. The authors present the possibility of carrying out the diplomas in cooperation with employers and institutions interested in employment of students who graduated Gdansk University of Technology, Faculty of Civil and Environmental Engineering and University of Warmia and Mazury, Faculty of Geodesy and Land Management (major:...
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Linux scheduler improvement for time demanding network applications, running on Communication Platform Systems
PublicationCommunication Platform Systems as ex. ATCA standard blades located in standardized chassis provides high level communication services between system peripherals. Each ATCA blade brings dedicated functionality to the system but can as well exist as separated host responsible for servicing set of task. According to platform philosophy these parts of system can be quite independent against another solutions provided by competitors....
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IMPROVING THE QUALITY OF EDUCATION THROUGH THE IMPLEMENTATION OF THE DIPLOMAS AND GROUP PROJECTS DURING ENGINEERING STUDIES IN COOPERATION WITH EMPLOYERS
PublicationThe quality of education is one of most important factors determining the job opportunity for graduates. The authors present the possibility of carrying out the diplomas in cooperation with employers and institutions interested in employment of students who graduated Gdansk University of Technology, Faculty of Civil and Environmental Engineering and University of Warmia and Mazury, Faculty of Geodesy and Land Management (major:...
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Wybrane problemy geotechniczne na terenach zurbanizowanych na przykładzie Trójmiasta
PublicationWybrane, współczesne problemy geotechniczne na terenach zurbanizowanych, miejskich i poprzemysłowych na przykładzie Trójmiasta. Dwie grupy problemów związane z podłożem oraz z otoczeniem inwestycji. Problemy związane z wodą gruntową i jej przepływem, z zanieczyszczeniami oraz pozostałościami budowlanymi z przeszłości. Sąsiedztwo zabudowy i brak miejsca. Przykłady z zrealizowanych obiektów budowlanych. Europejskie Centrum Solidarności,...
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Distributed Detection of Selected Features in Data Streams Using Grid-class Systems
PublicationThis chapter describes basic methodology of distributed digital signal processing. A choice of distributed methods of detection of selected features in data streams using grid-class systems is discussed. Problems related to distribution of data for processing are addressed. A mitigating method for data distribution and result merging is described.
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The calculation long-term physical field created by water flow around the ship
PublicationThe paper presents a description of the problems with fluid flow around a ship. Using the described solution of the problem were performed numerical calculations using the boundary element method. Were also presented preliminary results of the calculation of pressure fields at the bottom of the ship, taking into account the impact of the bottom.
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An Impact of Environmental Disturbances on Combined Cycle Power Plant Control
PublicationCombined cycle power plants operate at thermal efficiency approaching 60 percent. In the same time their performance presents several problems that have to be addressed. E.g. gas turbines are very sensitive to backpressure exerted on them by the heat recovery steam generators as well as to ambient pressure and temperature.
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Turbomachinery - Background
PublicationThe "Turbomachinery - Background" is the first part of a series of monographs devoted to different aspects of rotating machines. The book presents the main fundamentals which are necessary for the different problems of steam, gas, wind and water turbines as well as pumps, compressors and propellers which will discussed in detail in the subsequent parts of the series.
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INTEGRATION OF THE MOBILE PLATFORMS BASED ON SOCIAL NETWORK SERVICE DIRECTED AT USERS LOCALIZATION
PublicationThis paper presents an architecture overview and some aspects of implementation of the social network service directed at users localization. It shows how web services can be used as a tool for integrating different mobile platforms with a web application. The main focus is set on communication between system elements and related problems.
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Aggregated conducted interferences generated by group of asynchronous drives with deterministic and random modulation
PublicationThis paper addresses problems linked with electromagnetic interferences generated by group of three adjustable speed drives fed by frequency converters with deterministic and random modulation. Based on the experimental results it has been shown that decreasing of the conducted interferences in a case of random modulation is measuring phenomenon linked with selectivity of the EMI receiver.
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New perspective on the in vivo use of cold stress dynamic thermography in integumental reconstruction with the use of skin-muscle flaps
PublicationAmong the problems encountered by plastic surgeons is the reconstruction of defects following tumors. One of the reconstructive options is TRAM flap. Despite that anatomy is well-explored, marginal flap necrosis may develop. To minimize complications imaging examinations was designed to determine the degree of flap perfusion. One of them is the thermographic examination.
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Organisational methods in teaching ergonomics
PublicationCivilisation generates many problems connected with job, which cannot be resolved by one field of science that deals with matters fragmentarily, only from its own point of view. Ergonomics, i.e. synthetic knowledge about job, can solve these problems by using the resources of many fields, e.g. physiology, psychology, technical science or economy. The achievements of these fields are used in ergonomics and thus problems connected...
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The Changing Nature of In‐Between Spaces in the Transformation Process of Cities
PublicationIn the in‐between spaces of cities, there are many problems of various nature and scale: functional, spatial, economic, environmental, visual, and social. There are also some hidden potentials that can be activated. The aim of the article is to explore the possibilities of solving existing problems and to show the possibilities of using the potentials of in‐between spaces with regard to the changing nature of a city. The article,...
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A spline-based FE approach to modelling of high frequency dynamics of 1-D structures
PublicationIn this paper a computational methodology leading to the development of a new class of FEs, based on the application of continuous and smooth approximation polynomials, being splines, has been presented. Application of the splines as appropriately defined piecewise elemental shape functions led the authors to the formulation of a new approach for FEM, named as spFEM, where contrary to the well-known NURBS approach, the boundaries...
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Vision Zero in Poland
PublicationPoland’s experience of road safety work is relatively short. In the early 1990s road deaths soared to a staggering 8000 a year. A diagnosis found that Poland’s lack of systemic road safety action was to blame for those figures. In response, the state set up road safety bodies and commissioned road safety programs. In 2005, Poland followed the example of Sweden and adopted Vision Zero as a far-reaching concept of changes in road...
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Difference functional inequalities and applications.
PublicationThe paper deals with the difference inequalities generated by initial boundary value problems for hyperbolic nonlinear differential functional systems. We apply this result to investigate the stability of constructed difference schemes. The proof of the convergence of the difference method is based on the comparison technique, and the result for difference functional inequalities is used. Numerical examples are presented.
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Modern control strategy of bidirectional DAB converter with consideration of control nonlinearity
PublicationThis paper focuses on the control strategy for modern universal bidirectional Dual Active Bridge (DAB) converters for microgrid systems. An analysis of the converter equations was carried out, and typical problems related to the influence of dead time on the system operation were discussed. A closed control loop was developed, then tested by simulation and on a laboratory stand.
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A New Type of Macro-Elements for Efficient Two-Dimensional FEM Analysis
PublicationThis letter deals with a model order reduction technique applicable for driven and eigenvalue problems solved using the finite element method (FEM). It allows one to efficiently compute electromagnetic parameters of structures comprising small features that require strong local mesh refinement. The subdomains of very fine mesh are separated from the global domain as so called macro-elements that undergo model reduction. The macro-elements...
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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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Benchmarking the Digital Government Value Chain
PublicationDigital Government (DG) benchmarking is an academically vivid topic and, equally important, a tool with the potential to provide valuable insights to policymakers and public managers responsible for digital policies at the level of countries and international bodies. Alas, this potential remains largely untapped in the current DG benchmarking practice. In our study, we identify the reasons and propose a way of mitigating them....
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Role of the Synergistic Interactions of Environmental Pollutants in the Development of Cancer
PublicationThere is a growing awareness that the large number of environmental pollutants we are exposed to on a daily basis are causing major health problems. Compared to traditional studies that focus on individual pollutants, there are relatively few studies on how pollutants mixtures interact. Several studies have reported a relationship between environmental pollutants and the development of cancer, even when pollutant levels are below...
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Isoprostanes-Biomarkers of Lipid Peroxidation: Their Utility in Evaluating Oxidative Stress and Analysis
PublicationIsoprostanes (IsoPs) are key biomarkers for investigating the role of free radical generation in the pathogenesis of human disorders. To solve IsoPs-related problems with regard to isoprostanes, analytical tools are required. This paper reviews the problems and trends in this field focusing on the methodology for assaying biomarkers in exhaled breath condensate (EBC) samples. A large amount of work has been done in the qualitative...
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A higher order transversely deformable shell-type spectral finite element for dynamic analysis of isotropic structures
PublicationThis paper deals with certain aspects related to the dynamic behaviour of isotropic shell-like structures analysed by the use of a higher order transversely deformable shell-type spectral finite element newly formulated and the approach known as the Time-domain Spectral Finite Element Method (TD-SFEM). Although recently this spectral approach is reported in the literature as a very powerful numerical tool used to solve various...
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Designing Aggregate KPIs as a Method of Implementing Decision-Making Processes in the Management of Smart Cities
PublicationThe aim of the paper is to present a concept of measuring the performance of city management processes by use of a concept of aggregate KPIs. In the management of organizations and, as a consequence of the use of a common design framework also in the management of cities, silo KPIs are commonly used to show the statuses of the processes of organizations/cities. Thus the question arises as to what extent aggregate KPIs, as proposed...
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State of the art electronic nose technology and future trends
PublicationThis chapter briefly reviews the progress in field of artificial olfaction and demonstrates future trends in electronic nose technology. The discussion about e-nose concern also a big challenge for the pattern recognition (PARC) systems due to several particular problems they involve. Finally, the application of e-nose in different areas of life is given.
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Multipath Complex Root Tracing
PublicationThe problem of multipath root tracing is being addressed in this communication. The self-adaptive complex root tracing algorithm, which was previously utilized for the investigation of various propagation and radiation problems, is analyzed here for the cases when the traced characteristic bifurcates. A procedure of multiroute detection is proposed and demonstrated on the coaxially loaded cylindrical waveguide example.
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Reactive Energy Billing in Operator Tariffs in Poland
PublicationThe paper describes the current method of reactive energy billing in the tariffs of distribution grid operators in Poland. The current solutions are subject to critical assessment. Issues related to the motivation effect of the current solutions on consumers are analysed. Problems that occur in relation with connecting distributed generators to the distribution grid and challenges related to prosumer billing are indicated.
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Case studies of resonance phenomena in high voltage overhead power lines with shunt reactors
PublicationMisguided design of the towers of power transmission lines can lead to serious problems such as voltage asymmetry, overvoltages, electric arc extinction difficulties or resonance – in case of double circuit line with shunt reactors. The paper points out those threats on example of 400 kV double circuit overhead transmission line with shunt reactors.
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Modelling processes for Polish civil aviation market
PublicationThe present , paper is the first step in research of Polish civil aviation market, focusing on the area of civil, legacy airlines. First, the market is described with its players, current conditions and its main problems. Next, the tools which are currently used for the prognosis processes are presented. Finally, the idea of a new model (fuzzy model) for the process of prognosis is presented.