Filtry
wszystkich: 1844
wybranych: 1602
-
Katalog
- Publikacje 1602 wyników po odfiltrowaniu
- Czasopisma 68 wyników po odfiltrowaniu
- Konferencje 4 wyników po odfiltrowaniu
- Osoby 45 wyników po odfiltrowaniu
- Projekty 1 wyników po odfiltrowaniu
- Kursy Online 80 wyników po odfiltrowaniu
- Wydarzenia 3 wyników po odfiltrowaniu
- Dane Badawcze 41 wyników po odfiltrowaniu
Filtry wybranego katalogu
wyświetlamy 1000 najlepszych wyników Pomoc
Wyniki wyszukiwania dla: problems
-
The theoretical description of friction force in bio-joints as function of cartilage roughness
PublikacjaWartości sił tarcia w naturalnych stawach człowieka a szczególnie w endoprotezach stawu biodrowego rzutują na proces zużywania się powierzchni stawowych. Dlatego problem wyznaczania sił tarcia w biołożyskach jest bardzo istotny. W trakcie chodzenia mamy co najmniej ruch sferycznej powierzchni głowy w dwóch różnych kierunkach dla naturalnych i sztucznych stawów biodrowych człowieka. Dlatego też siły tarcia występują co najmniej...
-
Non-Newtonian lubrication of human hip joint for unsteady impulsive motion
PublikacjaTematem niniejszej pracy są parametry smarowania lepkosprężystą cieczą synowialną stawu biodrowego człowieka w czasie kilku, kilkunastu a nawet kilkudziesięciu mikrosekund po doznanym urazie. W niniejszej pracy rozpatruje się urazy wywołujące zmniejszenie lub zwiększenie wysokości i zmiany kształtu szczeliny stawu, które to zmiany po pewnym określonym czasie po doznanym urazie mogą zanikać. W konsekwencji takich urazów i to w...
-
About nutrient liquid flow between potential flow and cartilage surface in bioreactor
PublikacjaW niniejszej pracy wyznaczony został przepływ cieczy odżywczej o właściwościach nienewtonowskich w cienkiej warstwie granicznej w pobliżu powierzchni komórek chrząstki (chondrocytu) podczas hodowli w bioreaktorze. Ruch cieczy w warstwie granicznej jest wywołany wydatkiem przepływu dostarczanej cieczy do bioreaktora. Ponadto prędkość przepływu cieczy w warstwie granicznej wokół hodowanych komórek chrząstki stawowej jest uzależniona...
-
Flow and friction around the growing cartilage cells
PublikacjaInżynieria tkankowa jest jedną z najszybciej rozwijających się dziedzin biotechnologii stosowanej. Nowe metody badawcze tej nauki mogą być rozwiązane jedynie przy wzajemnej współpracy biologów, tribologów, mechaników, ortopedów klinicystów.Schorzenia chrząstki stawowej dotyczą milionów ludzi na świecie, często nawet w młodym wieku. Od kilkunastu lat z powodzeniem prowadzone są próby rekonstrukcji chrząstki stawowej oparte na dwóch...
-
Projektowanie hydrodynamicznych łożysk wzdłużnych z wykorzystaniem optymalizacji kształtu szczeliny smarowej
Publikacjaw pracy przedstawiono metodę projektowania hydrodynamicznych łożysk wzdłużnych z wykorzystaniem optymalizacji kształtu szczeliny smarowej. Optymalizacja kształtu szczeliny smarowej, pierwszy etap projektowania łożyska, jest przeprowadzana bez żadnych wstępnych założeń dotyczących postaci konstrukcyjnej łożyska natomiast uwzględniane są wymagania charakterystyczne dla zadanych warunków pracy łożyska. W następnym etapie poszukuje...
-
Forecasting of fatigue life of laser welded joints
PublikacjaW pracy przedstawiono podstawowe dane na temat stalowych paneli typu sandwich. Zaprezentowano wyniki testów zmęczeniowych elementarnych połączeń teowych spawanych laserowo. Omówiono szczegółowo te cechy, które mają istotny wpływ na statyczne i zmęczeniowe własności złącza. Na podstawie przedstawionych wyników badań zmęczeniowych elementarnych połączeń spawanych laserowo uzyskano krzywą projektową S-N dla jednego z pokazanych modeli...
-
Analysis of the amount of retained austenite in the structure of steel rolls for sheet rolling
Publikacja -
КОНЦЕПТУАЛІЗАЦІЯ ПОНЯТТЯ ІНСТИТУТ РИНКУ СТРАХОВИХ ПОСЛУГ НА ОСНОВІ НЕОКЛАСИЧНОЇ ЕКОНОМІКИ
Publikacja -
Planowanie obsług profilaktycznych złożonego obiektu technicznego
PublikacjaZdefiniowano kryterium efektywności eksploatacji złożonego obiektu technicznego, przedstawiono koncepcję prognozowania zasobów godzin pracy w zmieniających się warunkach eksploatacji oraz modele planowania obsług profilaktycznych obiektów.
-
Produktywność eksploatacji maszyn i urządzeń technicznych
PublikacjaW artykule przedstawiono nowe podejście do analizy technicznio-ekonomicznej przedsiębiorstwa, ukierunkowane na uzupełnienie sformułowania pojęcia produktywności eksploatacji maszyn i urządzeń technicznych. Po stronie efektów wyróżniono: efekty użytkowania, bezpieczeństwo pracy, jakość produktów uzależnioną od stanu technicznego urządzeń, gotowość techniczną, nieuszkadzalność maszyn i urządzeń technicznych. Po stronie nakładów uwzględniono:...
-
Environmental risk measure of ships
PublikacjaW artykule wyszczególniono najistotniejsze zanieczyszczenia uwalniane podczas eksploatacji statków. Przedyskutowano norweską propozycję indeksacji środowiskowej statków. Zaproponowano probabilistyczny model do oceny ryzyka stwarzanego przez statki względem środowiska morskiego oraz miarę tego ryzyka. Przedstawiono także wyniki badań wpływu niezawodnośći elementów technicznych i poziomu wyszkolenia załogi na roczne ryzyko środowiskowe...
-
Wodór w warstwach wierzchnich smarowanych węzłów ślizgowych
PublikacjaPodano wyniki badań wpływu czasu oddziaływania warstwy oleju smarowego na ilość wodoru dyfundującego do warstwy wierzchniej stalowych próbek. Zawartość wodoru rosła z czasem kontaktu. Badania w podczerwieni widm olejów po kontakcie ze stalą wykazały istotne zmiany wywołane przez dysocjacyjną chemisorpcję węglowodorów.
-
Methodological aspects of functional safety assessment
PublikacjaW artykule przedstawiono aktualne problemy analizy ryzyka i modelowania probabilistycznego w zarządzaniu bezpieczeństwem funkcjonalnym w cyklu życia systemów związanych z bezpieczeństwem. Zostały wyróżnione dwa podstawowe etapy w cyklu życia tych systemów, a mianowicie etap projektowania i etap eksploatacji. Z powodu złożoności i niepewności może być użyteczna w analizie ryzyka i modelowaniu probabilistycznym informacja zarówno...
-
SatBałtyk – A Baltic environmental satellite remote sensing system – an ongoing project in Poland. Part 2: Practical applicability and preliminary results**This work was carried out within the framework of the SatBałtyk project funded by the European Union through European Regional Development Fund, (contract No. POIG.01.01.02-22-011/09 entitled ‘The Satellite Monitoring of the Baltic Sea Environment’) and also as a part of IO PAS’s statutory research.The paper was presented in part at the 6th International Conference ‘Current Problems in the Optics of Natural Waters’, St. Petersburg, Russia, 6–10 September 2011.
Publikacja -
SatBałtyk – A Baltic environmental satellite remote sensing system – an ongoing project in Poland. Part 1: Assumptions, scope and operating range**This work was carried out within the framework of the SatBałtyk project funded by the European Union through European Regional Development Fund, (contract No. POIG.01.01.02-22-011/09 entitled ‘The Satellite Monitoring of the Baltic Sea Environment’) and also as a part of IO PAS’s statutory research.The paper was presented in part at the 6th International Conference ‘Current Problems in the Optics of Natural Waters’ St. Petersburg, Russia, 6–10 September 2011.
Publikacja -
QUANTITATIVE EASING POLICY AND ITS IMPACT ON THE GLOBAL ECONOMY
PublikacjaBased on the analysis of the impact of quantitative easing policies on the global economy, there was concluded that the world’s largest central banks and widespread debt stimulation have created the model of economic growth. This model was based on the productivity growth. The lack of productivity growth in the developed world, the active integration of developing countries (first of all China and India) in the global economy have...
-
Saga rodzinna — próba uporządkowania i konceptualizacji gatunku
Publikacja -
Badania wytrzymałości zmęczeniowej stopów łożyskowych przy wirującym wektorze obciążenia.
PublikacjaW pracy przedstawiono wyniki zmęczeniowych badań warstw ślizgowych z wybranych stopów łożyskowych obciążonych wirującą reakcją łożyskową. Prezentowane przypadki pęknięć zmęczeniowych panwi łożyskowych uzyskano w testach zmęczeniowych prowadzonych na stanowisku MWO w laboratorium tribologicznym Politechniki Gdańskiej.
-
Weighted difference schemes for systems of quasilinear first order partial functional differential equations
PublikacjaThe paper deals with initial boundary value problems of the Dirichlet type for system of quasilinear functional differential equations. We investigate weighted difference methods for these problems. A complete convergence analysis of the considered difference methods is given. Nonlinear estimates of the Perron type with respect to functional variables for given functions are assumed. The proof of the stability of difference problems...
-
A comprehensive overview of software product management challenges
PublikacjaThe principal focus of software product management is to ensure the economic success of the product, which means to prolong the product life as much as possible with modest expenditures to maximizs profits. Software product managers play an important role in the software development organization while being responsible for the strategy, business case, product roadmap, high-level requirements, product deployment (release-management),...
-
Using similar classification tasks in feature extractor learning
PublikacjaThe article presents and experimentally verify the idea of automatic construction of feature extractors in classification problems. The extractors are created by genetic programming techniques using classification examples taken from other problems then the problem under consideration.
-
Method of lines for nonlinear first order partial functional differential equations.
PublikacjaClassical solutions of initial problems for nonlinear functional differential equations of Hamilton--Jacobi type are approximated by solutions of associated differential difference systems. A method of quasilinearization is adopted. Sufficient conditions for the convergence of the method of lines and error estimates for approximate solutions are given. Nonlinear estimates of the Perron type with respect to functional variables...
-
Method of lines for Hamilton-Jacobi functional differential equations.
PublikacjaInitial boundary value problems for nonlinear first order partial functional differential equations are transformed by discretization in space variables into systems of ordinary functional differential equations. A method of quasi linearization is adopted. Suffcient conditions for the convergence of the method of lines and error estimates for approximate solutions are presented. The proof of the stability of the diffrential difference...
-
On the problem of optimised allocation of water quality sensors and actuators in DWDS
PublikacjaThe problems of water quality sensors and actuators placement in drinking water distribution systems (DWDSs) are addressed as separate, primarily. However, against the background of control systems theory, the nature of DWDSs dynamics indicates that these both problems are interdependent and impact the design of related water quality monitoring and control structures and algorithms. The research work presented in this paper is...
-
Scattering and Propagation Analysis for the Multilayered Structures Based on Field Matching Technique
PublikacjaA semi-analytical method is employed to the analysis of scattering and guiding problems in multilayer dielectric structures. The approach allows to investigate objects with arbitrary convex cross section and is based on the direct field matching technique involving the usage of the field projection at the boundary on a fixed set of orthogonal basis functions. For the scattering problems the scattered field in the far zone is calculated...
-
Active Kriging-based conjugate first-order reliability method for highly efficient structural reliability analysis using resample strategy
PublikacjaEfficient structural reliability analysis method is crucial to solving reliability analysis of complex structural problems. High-computational cost and low-failure probability problems greatly limit the efficiency in structural reliability analysis problems, causing the safety and reliability of the structure to be questioned. In this work, a highly efficient structural reliability analysis method coupling active Kriging algorithm...
-
Modernity and postmodernity in architectural education
PublikacjaThe purpose of this article is to present a philosophical education strategy for architecture and interior architecture faculties. The approach is the result of trial and error in lectures and debates with students of philosophical courses in these fields. The presented article is not a result of empirical research, but rather a report on the problems encountered and proposals for their solution. The experience gained from conducting...
-
Sacral sound-engineering
PublikacjaOrganologic and campanologic acoustical problems due to applications to sacral objects are characterized on ground of numerous reviewed publications and engineering reports. Participations of several involved research centres, mostly Polish, at solving these problems are evaluated. Some desirable future developments are indicated. Appendices bring examples of documentation on selected investigated objects.
-
Practical aspects of design and operation of amphibious craft for rescue purposes
PublikacjaThe paper presents the selected problems of design and operation of amphibious craft for rescue purposes. The result of research on the amphibious rescue units allowed formulating the general conclusions with respect to the proper selection of the main design parameters, program of model tests and full scale trials for the amphibious craft. The most important design problems related to the water characteristics are presents and...
-
Barriers of Cross-cultural Interactions According to the Research Findings
PublikacjaThe aim of this article is to label major cultural barriers and to present results of empiricalfindings referring to barriers to intercultural interactions in foreign subsidiaries oftransnational corporations (TNCs). The qualitative research was conducted in TNCs'foreign subsidiaries operating in Poland in the winter of 2009/2010. The articledescribes how the respondents perceived the problems in cooperation with foreigners,defines...
-
Usefulness of the voltamperometric method for assessment of the purity of soil
PublikacjaThis paper presents a voltammetric analysis of soil. It shows that the voltammetry is a useful method for the assessment of soil contaminated with heavy metal ions. There are two major problems with voltammetry analysis: the diffusion coefficient and the measurement system. The paper contains a short literature study of mathematical equations and a study of differences between soil and water measurements. Suggestions of the solution...
-
Portable raman spectrometer with two excitation wavelengths
PublikacjaSelected problems of development of a portable Raman spectrometer having small size, reduced power consumption and robust construction are shown. The device dedicated for semiskilled personnel uses two lasers: 785nm and 355nm. Results of preliminary tests are presented. Also data processing procedures as well as problems referred to Raman signals acquisition through packages and influence of interfering signals are discussed.
-
Monotone iterative method to second order differential equations with deviating arguments involving Stieltjes integral boundary conditions
PublikacjaWe use a monotone iterative method for second order differential equations with deviating arguments and boundary conditions involving Stieltjes integrals. We establish sufficient conditions which guarantee that such problems have extremal solutions in the corresponding region bounded by lower and upper solutions. We also discuss the situation when problems have coupled quasi-solutions. We illustrate our results by three examples.
-
Engineering Analysis with ANSYS Software Second Edition
PublikacjaThe best way to learn complex systems is by means of hands-on experience. With an innovative and clear tutorial based approach, this powerful book provides a comprehensive introduction to the fundamental areas of engineering analysis needed on research or commercial engineering projects. With its detailed step-by-step explanations and sample problems, this book will develop the reader's understanding of FEA and their ability to...
-
Positive solutions for second order impulsive differential equations involving Stieltjes integral conditions
PublikacjaIn this paper we investigate integral boundary value problems for fourth order differentialequations with deviating arguments.Wediscuss our problem both for advanced or delayedarguments. We establish sufficient conditions under which such problems have positivesolutions. To obtain the existence of multiple (at least three) positive solutions, we use afixed point theorem due to Avery and Peterson. An example is also included to...
-
The Dynamical Projectors Method Hydro and Electrodynamics
PublikacjaThe dynamical projectors method proves to reduce a multicomponent problem to the simplest one-component problem with its solution determined by specific initial or boundary conditions. Its universality and application in many different physical problems make it particularly useful in hydrodynamics, electrodynamics, plasma physics, and boundary layer problems. A great variety of underlying mechanisms are included making this book...
-
The use of innovative application in creating new marketing space for cultural and entertainment events in the local market
PublikacjaThe following article describes the problems concerning marketing of mass events in the local market and potential solutions. In the first part the barriers that occur in communication between the organizers and the articipants are defined. In the process of identifying problems the results of research conducted for the needs article were used. In following sections the solution with use of Smartphone app is shown. The features that...
-
Stereoscopy in Graphics APIs for CAVE Applications
PublikacjaThe paper compares the advantages and disadvantages of a variety of Graphics Application Programming Interfaces (APIs) from the perspective of obtaining stereoscopy in applications written for a CAVE virtual reality environment. A number of problems have been diagnosed and an attempt has been made to solve them using OpenGL, DirectX 11 and 12, Vulkan, as well as the Unity Engine which can internally use DirectX, OpenGL and Vulkan,...
-
THE IPV4 TO IPV6 MIGRATION OF APPLICATIONS AND SERVICE
PublikacjaThis article presents the problems related to IPv4 to IPv6 migration of applications supporting network services. It summarizes the needs of executing such migration. It shows the basic problems of automating the migration process, having defined the basic terms, i.e.: a network service, a network application. It shows a sample implementation of the automation of the migration process between IP technologies for selected network...
-
Offshoring and outsourcing in Visegrad countries, Advantages and disadvantages.
PublikacjaOutsourcing and offshoring are getting more and more popular in the “new EU” coun-tries. They constitute very attractive venues for more developed EU countries to outsource or offshore their business activities. Authors of the article have investigated the advantages and disadvantages of locating outsourcing activities in each of the Visegrad (V4) countries. The authors have studied macroeconomic factors based on the reports of...
-
Analysis of Failures of High Speed Shaft Bearing System in a Wind Turbine
PublikacjaDuring the operation of wind turbines with gearbox of traditional configuration, consisting of one planetary stage and two helical stages high failure rate of high speed shaft bearings is observed. Such a high failures frequency is not reflected in the results of standard calculations of bearing durability. Most probably it can be attributed to atypical failure mechanism. The authors studied problems in 1.5 MW wind turbines of...
-
A higher order shell element for wave propagation in isotropic shell structures
PublikacjaThe presents the new multi mode higher order shell element for wave propagation problems in shell structures.
-
Electromagnetic Simulations with 3D FEM and Intel Optane Persistent Memory
PublikacjaAbstract—Intel Optane persistent memory has the potential to induce a change in how high-performance calculations requiring a large system memory capacity are conducted. This article presents what this change may look like in the case of factorization of large sparse matrices describing electromagnetic problems arising in the 3D FEM analysis of passive highfrequency components. In numerical tests, the Intel oneAPI MKL PARDISO was...
-
Control strategies and comparison of the Dynamic Voltage Restorer
PublikacjaThis paper focuses on a selection problems of mitigation of the voltage disturbance by of the Dynamic Voltage Restorers (DVR’s). In short form presented and discussed are the basis of different control strategies of the DVR. The main emphasis is placed on application of modern power electronic devices. Authors of this paper in particular occupy oneself with analysis of the power rating of the typically DVR topologies. These problems...
-
Scheduling with Complete Multipartite Incompatibility Graph on Parallel Machines: Complexity and Algorithms
PublikacjaIn this paper, the problem of scheduling on parallel machines with a presence of incompatibilities between jobs is considered. The incompatibility relation can be modeled as a complete multipartite graph in which each edge denotes a pair of jobs that cannot be scheduled on the same machine. The paper provides several results concerning schedules, optimal or approximate with respect to the two most popular criteria of optimality:...
-
Modernization and adaptation of historical interiors
PublikacjaModernization of the historical building's interior entails the need to take many decisions, often conflicting. Operational requirements, protection of the architectural heritage, fire-safety recommendations, construction regulations, all these aspects involve a whole set of problems that require a rational solution, respecting ambient architectural and historical value, as well as the needs arising from the planned transformation....
-
Variable Speed AC Drives with Inverter Output Filters
PublikacjaThe advance of variable speed drives systems (VSDs) engineering highlights the need of specific technical guidance provision by electrical machines and drives manufacturers, so that such applications can be properly designed to present advantages in terms of both energy efficiency and expenditure. This book presents problems and solutions related to inverter-fed electrical motors. Practically orientated, the book describes the...
-
Appendix E
PublikacjaThe advance of variable speed drives systems (VSDs) engineering highlights the need of specific technical guidance provision by electrical machines and drives manufacturers, so that such applications can be properly designed to present advantages in terms of both energy efficiency and expenditure. This book presents problems and solutions related to inverter-fed electrical motors. Practically orientated, the book describes the...
-
Thermal-FSI modeling of flow and heat transfer in a heat exchangerbased on minichanels
PublikacjaIn this paper selected numerical modelling problems for an advanced thermal-FSI ("Fluid Solid Interaction") mini-channel heat exchanger model are presented. Special attention is given to the heat transfer between the separated mediums for different mass flows. Similar modelling problems have also been discussed in the literature dedicated to numerical and theoretical modelling problems for typical heat exchangers [1, 2, 3]. Basic...
-
Brushing with additional cleaning restrictions
PublikacjaIn graph cleaning problems, brushes clean a graph by traversing it subject to certain rules. We consider the process where at each time step, a vertex that has at least as many brushes as incident, contaminated edges, sends brushes down these edges to clean them. Various problems arise, such as determining the minimum number of brushes (called the brush number) that are required to clean the entire graph. Here, we study a new variant...