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Semantics for an Interdisciplinary Computation
PublikacjaSemantics for an interdisciplinary computation is becoming increasingly difficult to capture while dealing with multi-domain problems. Expertise from Computer Science, Computer Engineering, Electrical Engineering, and other disciplines merges as engineering challenges in modern systems, such as, Cyber-Physical Systems, Smart Cities, and Bionic Systems must be tackled in a methodological manner. In this paper, a paradigm for formalization...
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The point estimate method in a reticulated shell reliability analysis
PublikacjaThe objective of this paper is to present an application of the point estimate method (PEM) that can determine the probabilistic moments for engineering structures. The method is reasonably robust and adequately accurate for a wide range of practical problems. It is a special case of numerical quadrature based on orthogonal polynomials. The main advantage of this method is that, unlike FORM or SORM, it is not necessary to carry...
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Chemical treatment of crystalline silicon solar cells as a main stage of pv modules recycling = Obróbka chemiczna krzemowych ogniw słonecznych jako najważniejszy etap w recyklingu modułów fotowoltaicznych
PublikacjaIn recent years, photovoltaic systems have gained worldwide recognition and popularity as a environmentally friendly way of solving energetic problems. However, a problem of utilizing worn out photovoltaic systems, amount of which will rapidly increase in the future, is yet to be solved. Establishing a technology of recycling and reusing obsolete photovoltaic panels is a necessity.Photovoltaic modules in crystalline silicon solar...
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Practical issues for the implementation of survivability and recovery techniques in optical networks
PublikacjaFailures 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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Dynamic Data Management Among Multiple Databases for Optimization of Parallel Computations in Heterogeneous HPC Systems
PublikacjaRapid development of diverse computer architectures and hardware accelerators caused that designing parallel systems faces new problems resulting from their heterogeneity. Our implementation of a parallel system called KernelHive allows to efficiently run applications in a heterogeneous environment consisting of multiple collections of nodes with different types of computing devices. The execution engine of the system is open for...
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Implementation of Business Intelligence in an IT organization - the concept of an evaluation model
PublikacjaThis paper presents the issue of assessing the validity and effectiveness of implementing a Business Intelligence system in an IT Support Organization. This entity provides IT services to external clients involving, in particular, the storage and processing of large amounts of data. The vast amount of realized projects and also incidents reported in connection with those projects prevented effective decisions from being made without...
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Improvement of Task Management with Process Models in Small and Medium Software Companies
PublikacjaSmall and medium software companies exhibit many special features that give reason for a dedicated approach to process improvement. They often cannot afford implementing maturity models or quality standards both in terms of time and money. Instead, they expect simpler solutions that can allow to run projects in more systematic and repeatable way, increase quality and knowledge management. In this paper, we present a method focused...
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Accuracy of the Discrete Green's Function Formulation of the FDTD Method
PublikacjaThis paper reports an evaluation of the accuracy of the discrete Greens function (DGF) formulation of the finite-difference time-domain (FDTD) method. Recently, the closed-form expression for the DGF and its efficient numerical implementation were presented, which facilitates applications of the DGF in FDTD simulations of radiation and scattering problems. So far, the accuracy of the DGF formulation of the FDTD method has been...
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Tmscl as a rate accelerating additive in acylations of amines with 5-(α-amino- α'-hydroxy)methylene meldrum's acids
PublikacjaAspects are presented of the acylation of amines, alcohols and thiols with 5-(α-amino- α'-hydroxy)methylene Meldrum's acids. We placed special emphasis on the acylation reaction of secondary amines with 5-(α-amino- α'-hydroxy)methylene Meldrum's acids, which, due to their basicity, caused problems concerning salt formation with a Meldrum acid derivative. We found that secondary amines, which react at the slowest rate and with a...
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Tinnitus Therapy Based on High-Frequency Linearization Principles - Preliminary Results
PublikacjaThe aim of this work is to present problems related to tinnitus symptoms, its pathogenesis, hypotheses on tinnitus causes, and therapy treatment to reduce or mask the phantom noise. In addition, the hypothesis on the existence of parasitic quantization that accompanies hearing loss has been recalled. Moreover, the paper describes a study carried out by the Authors with the application of high-frequency dither having specially formed...
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Wpływ dodatku odcieków składowiskowych do oczyszczanych ścieków komunalnych na wielkość frakcji ChZT
PublikacjaManaging landfill leachate is one of the most important problems with maintaining landfills. The aim of this study was to determine the influence on COD fraction of landfill leachate addition from 0,5% to 5% to raw wastewater. The results of this study show that soluble inert COD in wastewater and mixture wastewater with landfill leachate constituted the smallest percentage of total COD. Nonetheless this fraction (soluble inert...
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Space-Time Conservation Method applied to numerical solution of water hammer equations
PublikacjaArtykuł poświęcony jest metodzie czasoprzestrzennych objętości skończonych (STC) zastosowanej do przypadku uderzenia hydraulicznego w stalowym przewodzie pracującym pod ciśnieniem. Metoda STC ze względu na swoje własności numeryczne - m.in. wysoką dokładność - może być interesującą alternatywą dla tradycyjnych metod numerycznych, szczególnie w przypadku, gdy efekty numeryczne mają bardzo silny wpływ na rozwiązanie, tym samym utrudniając...
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Sources and Fate of PAHs and PCBs in the Marine Environment
PublikacjaThe assessment of a hazard resulting from the pollution of the environment by chemical compounds is in principle limited to the determination of their concentrations in its various compartments. But for solving many problems in this context, knowledge of the emission sources, transport pathways, and sites of deposition is of great benefit. By far the largest amounts of pollutants, regardless of where they were discharged, end up...
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Application tool for IP QoS network design
PublikacjaDespite the fact that differentiated-service-aware network implementation has been a widely discussed topic for quite some time, network design still proofs nontrivial. Well developed software could put an end to network designer's problems. This chapter describes work, which has been aimed at creating a comprehensive network design tool, offering a fair range of functionality and high reliability. The presented tool is able to...
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Scrutiny of power grids by penetrating PV energy in wind farms: a case study of the wind corridor of Jhampir, Pakistan
PublikacjaThis study examines the problems caused by intermittent renewable energy sources, especially wind farms, and suggests a different solar energy penetration strategy to improve their loading capacity. The study uses real-time data from a wind farm in Jhampir, Pakistan, to analyse and assess various aspects of grid stations connected to wind farms. Electrical Transient Analyzer Program is used to validate the results by linking...
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Hybrid Technique Combining the FDTD Method and Its Convolution Formulation Based on the Discrete Green's Function
PublikacjaIn this letter, a technique combining the finite-difference time-domain (FDTD) method and its formulation based on the discrete Green's function (DGF) is presented. The hybrid method is applicable to inhomogeneous dielectric structures that are mutually coupled with wire antennas. The method employs the surface equivalence theorem in the discrete domain to separate the problem into a dielectric domain simulated using the FDTD method...
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High Frequency Harmonics Emission of Modern Power Electronic AC-DC Converters
PublikacjaModern AC/DC converters with bidirectional power flow employing PWM boost topology generate harmonic distortions of input current in relatively high frequency range tightly related to modulation carrier frequency. These frequencies and its multiples in typical applications are usually located in frequency range from single up to several of kHz. Increased harmonic emission in this frequency range can easily and harmfully influence...
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Towards Open Research Data in the Economics Discipline
PublikacjaNowadays, Open Research Data, as one of the three pillars of Open Science (along with Open Access and Open Scholarly Communication), is gaining enormous attention from different academic and commercial environments. A wide range of scientific disciplines represent and produce different types of data and at the same time, gather different issues and problems in terms of sharing and dissemination research output. This chapter aims...
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Computational modelling of historic masonry railroad arch bridges
PublikacjaThe problems encountered during the analyzes of structural response of historic masonry railroad arch bridges are described in this paper. The attention is mainly focused on the stiffness of the masonry arches, their strengths and appropriate estimation of railroad load intensity. Issues related to computational modelling of two, existing, almost 130 years old masonry arch railroad bridges are presented in this context. The main...
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Adapting education to a changing climate: preparing architecture students for climate-resilient design
PublikacjaIn this article, the authors explore the connection between climate change and the fields of architecture and urban planning. With the increasing frequency of flooding and extreme weather events, the built environment is confronting challenges in terms of sustainability and resilience. To meet these problems, it is necessary to prepare various specialists to assume responsibility for making future decisions. The authors of this...
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Risks caused by microbiologically influenced corrosion in diesel fuel storage tanks
PublikacjaMicrobiologically influenced corrosion (MIC) poses serious problems for the petrochemical and refinery industries. Particularly favourable conditions for MIC arise in storage tanks and transmission pipelines for mixtures of diesel oil with the addition of a biocomponent (in Poland 7%). The best conditions for the development of MIC occur at the fuel-water interface, where microorganisms are provided with a source of food and water,...
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Theoretical Model of Acoustic Wave Propagation in Shallow Water
PublikacjaThe work is devoted to the propagation of low frequency waves in a shallow sea. As a source of acoustic waves, underwater disturbances generated by ships were adopted. A specific feature of the propagation of acoustic waves in shallow water is the proximity of boundaries of the limiting media characterised by different impedance properties, which affects the acoustic field coming from a source situated in the water layer “ deformed”...
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Application of the discrete Green's function-based antenna simulations for excitation of the total-field/scattered-field interface in the FDTD method
PublikacjaIn this article, the discrete Green's function formulation of the finite-difference time-domain (DGF-FDTD) method is proposed for simulation of wire antennas irradiating inhomogeneous dielectric scatterers. Surface equivalence theorem in the discrete domain is used to separate the problem into an inhomogeneous domain and a wire antenna that are simulated with the use of FDTD and DGF-FDTD, respectively. Then, the excitation of the...
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Scrutiny of power grids by penetrating PV energy in wind farms: a case study of the wind corridor of Jhampir, Pakistan
PublikacjaThis study examines the problems caused by intermittent renewable energy sources, especially wind farms, and suggests a different solar energy penetration strategy to improve their loading capacity. The study uses real-time data from a wind farm in Jhampir, Pakistan, to analyse and assess various aspects of grid stations connected to wind farms. Electrical Transient Analyzer Program is used to validate the results by linking these...
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Greenness assessment of analytical methods used for antibiotic residues determination in food samples
PublikacjaFood of animal origin plays an important role in ensuring a healthy and sustainable human diet. However, residues of pharmaceuticals, especially antibiotics, can be the cause of many health problems. To protect consumers and improve food quality, analytical methods used to determine contaminants should be simple, selective, and have high throughput and low detection limits. Recently, greenness metric tools have proven useful in...
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Miniaturized solid phase extraction techniques for different kind of pollutants analysis: State of the art and future perspectives – PART 2
PublikacjaDetermination of pollutants present in environmental samples at a low concentration level very often requires the analytical protocol that includes analytes isolation and/or enrichment prior to the final quantification. Miniaturized SPE offers an interesting alternative to LLE. Nowadays, many types of sorbents are available and can be used as selective materials for extraction of varied analytes in different kinds of samples. The...
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Estimation of the Maximum Permissible PV Power to be Connected to the MV Grid
PublikacjaIn recent decades, a significant increase in the share of renewable energy sources in power grids at various voltage levels has been observed. A number of articles have been published highlighting emerging problems in low-voltage grids with a large share of prosumers and in medium- and high-voltage grids to which photovoltaic (PV) plants are connected. The article analyzes the medium-voltage grid in terms of the possibility of...
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Engineering method of tire rolling resistance evaluation
PublikacjaTire rolling resistance is one of the most difficult tire parameters to measure. The reason is that for modern tires the force of rolling resistance corresponds to 0.5–1% of tire load, thus measurements of very small forces must be performed in a heavily loaded system. This constitutes great problems, especially in road conditions. Laboratory measurements are easier to perform, as the environment may be better controlled, but roadwheel...
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Computer Supported Analysis of the Human Body Surface Area
PublikacjaRecent scientific studies show the growing importance of the coefficients: BSA and TBSA, as an alternative to the widely used BMI. The relevant indicators are widely used in medicine, including such areas as: the treatment of burns, chemotherapy, dermatology and toxicology; as benchmarks when calculating doses of drugs and fluids. The particular problems concerning this subject are: the change of the reference parameter value which...
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A Systematic Literature Review on Implementing Non-functional Requirements in Agile Software Development: Issues and Facilitating Practices
PublikacjaAgile Software Development methods have become a widespread approach used by the software industry. Non-functional requirements (NFRs) are often reported to be a problematic issue for such methods. We aimed to identify (within the context of Agile projects): (1) the issues (challenges and problems) reported as affecting the implementation of NFRs; and (2) practices that facilitate the successful implementation of NFRs. We conducted...
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Onboard Energy Storage and Power Management Systems forAll-Electric Cargo Vessel Concept
PublikacjaThis paper presents an innovative approach to the design of a forthcoming, fully electric-powered cargo vessel. This work begins by defining problems that need to be solved when designingvessels of this kind. Using available literature and market research, a solution for the design of apower management system and a battery management system for a cargo vessel of up to 1504 TEUcapacity was developed. The proposed solution contains...
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A hyperelastic model for soils with stress-induced and inherent anisotropy
PublikacjaIn this paper, modelling of the superposition of stress-induced and inherent anisotropy of soil small strain stiffness is8presented in the framework of hyperelasticity. A simple hyperelastic model, capable of reproducing variable stress-induced9anisotropy of stiffness, is extended by replacement of the stress invariant with mixed stress–microstructure invariant to10introduce constant inherent cross-anisotropic component. A convenient...
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Is This Distance Teaching Planning That Bad?
PublikacjaIn spring 2020, university courses were moved into the virtual space due to the Covid-19 lockdown. In this paper, we use experience from courses at Gdańsk University of Technology and ETH Zurich to identify core problems in distance teaching planning and to discuss what to do and what not to do in teaching planning after the pandemic. We conclude that we will not return to the state of (teaching) affairs that we had previously....
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On a comparison principle and the uniqueness of spectral flow
PublikacjaThe spectral flow is a well-known quantity in spectral theory that measures the variation of spectra about 0 along paths of selfadjoint Fredholm operators. The aim of this work is twofold. Firstly, we consider homotopy invariance properties of the spectral flow and establish a simple formula which comprises its classical homotopy invariance and yields a comparison theorem for the spectral flow under compact perturbations. We apply...
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Analytical solution of non-stationary heat conduction problem for two sliding layers with time-dependent friction conditions
PublikacjaIn this article we conduct an overview of various types of thermal contact conditions at the sliding interface. We formulate a problem of non-stationary heat conduction in two sliding layers with generalized thermal contact conditions allowing for dependence of the heat-generation coefficient and contact heat transfer coefficient on time. We then derive an analytical solution of the problem by constructing a special coordinate...
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Phage therapy as a novel strategy in the treatment of urinary tract infections caused by E. coli
PublikacjaUrinary tract infections (UTIs) are regarded as one of the most common bacterial infections affecting millions of people, in all age groups, annually in the world. The major causative agent of complicated and uncomplicated UTIs are uropathogenic E. coli strains (UPECs). Huge problems with infections of this type are their chronicity and periodic recurrences. Other disadvantages that are associated with UTIs are accompanying complications...
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Applying case studies to teaching architectural investment
PublikacjaCase studies enable students to encounter practical issues during their education. Experiments conducted in class employing this method often feature simplified models of real-world situations. However, they still enable students to encounter actual problems, to which theoretical knowledge is applied. In architectural education, students carrying out semester projects usually rely on data provided by the teacher, without wondering...
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Optimization of Wireless Networks for Resilience to Adverse Weather Conditions
PublikacjaIn this chapter, we consider how adverse weather conditions such as rain or fog affect the performance of wireless networks, and how to optimize these networks so as to make them robust to these conditions. We first show how to analyze the weather conditions in order to make them useful for network optimization modelling. Using an example realistic network, we show how to optimize two types of wireless networks: free-space optical...
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Design of dimensionally stable composites using efficient global optimization method
PublikacjaDimensionally stable material design is an important issue for space structures such as space laser communication systems, telescopes, and satellites. Suitably designed composite materials for this purpose can meet the functional and structural requirements. In this paper, it is aimed to design the dimensionally stable laminated composites by using efficient global optimization method. For this purpose, the composite plate optimization...
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On Applications of Elements Modelled by Fractional Derivatives in Circuit Theory
PublikacjaIn this paper, concepts of fractional-order (FO) derivatives are reviewed and discussed with regard to element models applied in the circuit theory. The properties of FO derivatives required for the circuit-level modeling are formulated. Potential problems related to the generalization of transmission-line equations with the use of FO derivatives are presented. It is demonstrated that some formulations of FO derivatives have limited...
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Utilization of Gaseous Carbon Dioxide and Industrial Ca-rich Waste for Calcium Carbonate Precipitation: A Review
PublikacjaTechnologies for the management of various types of waste and the production of useful products from them are currently widely studied. Both carbon dioxide and calcium-rich waste from various production processes are problematic wastes that can be used to produce calcium carbonate. Therefore, the purpose of this paper is to provide an overview about the state of the development of processes that use these two wastes...
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THEORETICAL POTENTIAL OF HYDROGEN PRODUCTION FROM TEXTILES WASTES IN POMERANIAN REGION BY MEANS OF DARK FERMENTATION
PublikacjaModel has been developed for calculating theoretical mass of hydrogen produced from textile wastes by mean of dark fermentation. As vegetable fibres wastes were chosen two mostly used — cotton and linen (flax). As the synthethic carbohydrate rich fiber was chosen viscose. In the background there were introduced: problems of dark fermentation, characteristics of textile material structure. Additionally pathways of the process...
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RECODIS: Resilient Communication Services Protecting End-user Applications from Disaster-based Failures
PublikacjaDisaster-based failures can seriously disrupt any communication network, making its services unavailable. Such disruptions may be caused by natural disasters, technology-related failures, or malicious attacks, and they are observably increasing in number, intensity and scale. When network services that are a part of critical infrastructure become unavailable, commercial and/or societal problems are inevitable. The issue of limiting...
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Towards Synthetic and Balanced Digital Government Benchmarking
PublikacjaReliable benchmarking is essential for effective management of the government digitalization efforts. Existing benchmarking instruments generally fail to support this target. One problem is the diversity of instruments, resulting in a split image of digital progress and adding ambiguity to policy decisions. Another problem is disconnect in assessing progress between digital and traditional “analog” governance, lending support to...
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The role of numerical tests in assessing road restraint system functionality
PublikacjaKey to understanding the needs and building road infrastructure management tools to prevent and mitigate run-off-road accidents is to identify hazards and their sources which are a result of wrong design, construction, and installation of road restraint systems. Building such tools requires advanced studies with field tests, simulations and models to demonstrate the effects of selected parameters on road user safety. The research...
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EIA in teaching sustainable development and environmental protection in engineering education
PublikacjaA multifaceted approach in teaching the environmental impact assessment (EIA) as a way to stress the role of environmental education in technical sciences is the focus of this article. The EIA is an example of an effective tool that supports spatial planning in implementing sustainable development. The aim is to present the idea and benefits of a facilitative and collaborative approach in teaching the EIA, stressing the role of...
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On the plastic buckling of curved carbon nanotubes
PublikacjaThis research, for the first time, predicts theoretically static stability response of a curved carbon nanotube (CCNT) under an elastoplastic behavior with several boundary conditions. The CCNT is exposed to axial compressive loads. The equilibrium equations are extracted regarding the Euler–Bernoulli displacement field by means of the principle of minimizing total potential energy. The elastoplastic stress-strain is concerned...
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DESIGN AND CONSTRUCTION OF TILTED WALLS IN ACCORDANCE WITH CODES' PROVISIONS ON THE EXAMPLE OF THE CONSTRUCTION OF THE MUSEUM OF THE SECOND WORLD WAR IN GDAŃSK
PublikacjaThe purpose of this article was to introduce the design and construction of tiled walls in accordance to codes' restrictions. The construction of the Museum of the Second World War in Gdańsk was chosen to be an example of its successful use in practice. Theoretical knowledge was based on PN-EN 1992-1-1:2008 and fib Model Code for Concrete Structures 2010. Although codes' recommendations seem curt, practice prove structural advance....
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Parallelization of Selected Algorithms on Multi-core CPUs, a Cluster and in a Hybrid CPU+Xeon Phi Environment
PublikacjaIn the paper we present parallel implementations as well as execution times and speed-ups of three different algorithms run in various environments such as on a workstation with multi-core CPUs and a cluster. The parallel codes, implementing the master-slave model in C+MPI, differ in computation to communication ratios. The considered problems include: a genetic algorithm with various ratios of master processing time to communication...
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Universities as Part of the Urban Transport System—Analysis Using the Example of the Gdansk University of Technology and Medical University of Gdansk
PublikacjaMany cities perceive academic function as a distinctive feature, representing the rank and prestige of the city. Universities provide places for work and learning for a high number of people and represent a significant proportion compared to the total city population (even 22%). Many of Polish universities are located in the urban structure in the form of spatially concentrated campuses, where the number of people working and studying...