Wyniki wyszukiwania - Biblioteka Nauki

1

Using the software of Navi-Trainer PRO 5000 simulator for assessment of the designed navigational infrastructure

100%

Czaplewski K. , Zwolan P.

Annual of Navigation

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2011

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tom No. 18

55--68

EN

The paper presents the possibility of using the navigational and maneuvering simulators software, for the verification of designed elements of navigational infrastructure. The article describes how to use the Navi - Trainer PRO 5000 simulator manufactured by Transas Marine to modeling sea waters. The Article is based on a scientific research project performed at the Institute of Navigation and Hydrography of Naval Academy of Gdynia. Project was aimed to check the possibility cut through the Vistula Spit and artificial connection the Gulf of Gdansk and Vistula Lagoon. The paper presents a description of creating a virtual basin with planned navigational infrastructure. There will by also presented the maneuvering tests for the assumed maximum ship model and few construction variants. Each of the project variants was tested in different hydro-meteorological conditions. The result of simulation tests are proposals that demonstrate the feasibility of the project and proposed possible changes affecting the level of safety.

2

Modelling Defeasibility in Law: Logic or Procedure?

100%

Prakken H.

Fundamenta Informaticae

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2001

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tom Vol. 48, nr 2,3

253-271

EN

This paper investigates whether current nonmonotonic logics are suitable for formalising the defeasibility of legal reasoning. It does so by studying the role of burden of proof in legal argument, in particular how allocations of burden of proof determine the required strength of counterarguments. It is argued that the two currently available modelling approaches both have some shortcomings. On the one hand, techniques for modelling burden of proof in nonmonotonic logics do not allow for shifts of the burden of proof from one party to the other. On the other hand, current procedural models of legal argument are too rigid, in that every counterargument induces a shift of proof burdens; this fails to respect that in legal reasoning burden shifts only occur in some cases. It is then shown how current dialectical models of defeasible reasoning can be adapted to overcome these shortcomings.

3

Modelling of mutual coupling in microstrip antenna arrays fed by microstrip line

100%

Kosowski M. , Zieniutycz W.

Kwartalnik Elektroniki i Telekomunikacji

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2004

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tom Vol. 50, z. 4

629-636

EN

The results of modelling of the coupling between the rectangular microstrip patches in linear array are presented. The equivalent circuit in form of a combination of the transmission lines stubs is proposed. It is then applied to model the coupling between two subsequent patches and two patches separated by third one. It is shown that such circuit well represents the mutual coupling in the narrow frequency band (4%). The equivalent circuit was applied to examine how the coupling modified the signals in the input ports of the array and as a consequence how the radiation pattern of the array is changed due to the coupling between the patches. Two linear arrays with cocecans radiation pattern were next designed to verify the theory: first which included proposed equivalent circuit and second one without the coupling (reference array). The results of measurements of VSWR and the radiation pattern for both arrays are presented and compared with theory.

4

Assessment of Odour Impact Range of Selected Waste Management Plant with the Use of Mathematical Tools (Model Tools)

100%

Romanik E. , Pawnuk M. , Sówka I.

Journal of Ecological Engineering

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2019

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tom Vol. 20, nr 10

94--101

EN

One of the many factors that can significantly affect the quality of human life in cities is odour pollution. The progressing industrialization mean that objects that can contribute to odour emission can be found in the immediate neighbourhood of the residential areas. The close proximity of such objects may contribute to odour nuisance. The scope of this work was to determine the extent of the odour impact associated with the functioning of the technological composting process for biodegradable waste at the Utilization Plant. In the study, biofilter and compost ripening area were considered as main odour emissions sources. The odour dispersion modelling from selected odour sources was performed with the use of Operat Fb software, the calculation scheme of which is consisted in the guidelines from the Regulation of the Minister of the Environment of 26 January 2010. The odour dispersion modelling was performed for two different scenarios. The first, representing the current state of the considered waste utilization plant and the second one represents the improvement option by applying encapsulation of the ripping area and the use of a biofilter with 98% efficiency. The calculations carried out showed a reduction of the odour concentration value in the second variant compared to the first variant. The odour emission from the waste utilization plant amounted to 2,027,100 ouE/s in the first scenario while in the second variant – 52,569 ouE/s. The highest obtained values of maximum annual average concentrations were 9,247 ouE/m3 for the first scenario and 874 ouE/m3 for the second scenario, respectively. The highest average concentration reacged 1,405 ouE/m3 for the first scenario and 181 ouE/m3 for the second scenario. The highest exceedance frequencies of are 100% for the first scenario and 99.7 for the second scenario. The reduction ratio for emission is 0.97%, for the maximum odour concentrations is 0.91% , the average annual odour concentrations is 0.87% and the frequency of exceeding the maximum odour concentrations is 0.003%. The application of the mathematical model allowed for the assessment of the reduction of the odour impact of the examined object and the validity of the applied method of reducing odour emissions.

5

Optimization methods modeling and simulation of production systems

100%

Plinta D.

Applied Computer Science

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2009

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tom Vol. 5, no 1

81--92

EN

The use of the modelling and simulation method in improving production systems is presented. In the analysed example, two stages were distinguished: creation of the simulation model and optimization. The second stage is illustrated by the practical examples of the use of different optimization methods like the orthogonal plan of Taguchi and fuzzy control. By using simulation connected with optimization, it is possible to check almost all admissible variants of the proposed improvements comparatively quickly in order to evaluate them and to choose the best solution.

6

Analiza możliwości wykorzystania metod drganiowych w diagnozowaniu okrętowej linii wałów

100%

Grządziela A.

Przegląd Mechaniczny

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2007

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tom nr 11

32-37

PL

Zaproponowano wykorzystania metody drganiowej do oceny stanu technicznego okrętowej linii wałów. Przedstawiono podstawowe uszkodzenia eksploatacyjne oraz przykłady ich identyfikacji przy zastosowaniu analiz sygnałów drganiowych. Przeprowadzono dyskusję nad wynikami badań, wrażliwością symptomów oraz wykorzystaniem modelowania oddziaływań zewnętrznych jako źródła pobudzenia dynamicznego na układ napędowy.

EN

There were proposed utilization vibrational method in evaluation of technical condition of shipping shaft line. Basic operating failures and examples of identification using vibrational signals analysis have been presented. Experimental results, sensitivity of symptoms and utilization of external interactions modelling as a source of dynamic stimulation of power transmission system were discussed.

7

Weryfikacja modelu rozwoju mikrostruktury stali z mikrododatkiem niobu odkształcanej w zakresie dwufazowym

100%

Niżnik B. , Pietrzyk M. , Kuziak R.

Przegląd Mechaniczny

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2007

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tom nr 7-8

28-32

8

Wykorzystanie modelowania fizycznego do określenia rozkładu sił w matrycach do kucia wspornika

100%

Kocańda A.

Przegląd Mechaniczny

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2007

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tom nr 7-8

25-27

PL

Przedstawiono metodę wyznaczania sił pionowych i bocznych w procesie kucia wspornika. Wykorzystano w tym celu modelowanie fizyczne i dynamometr sześcioosiowy, na którym zamontowano matrycę do kucia. Odkształcaniu poddano przedkuwki z materiału woskowego. Przedstawiono wykres ewolucji wypadkowej sił bocznych ułatwiający wybór konstrukcji matrycy, w której działanie sił bocznych będzie zminimalizowane, co umożliwia otrzymywanie odkuwek o odpowiednio wysokiej dokładności wymiarowej.

EN

. A method to determine axial and lateral forces in bracket lever forging die has been presented. Physical modelling and six-axis transducer have been used in the experiments. Preforms have been made of wax material. As a result of experiments, a diagram showing evolution of lateral forces has been prepared. This diagram could be very helpful in such a die design which would minimize the influence of lateral forces on geometrical accuracy of forgings.

9

Numeryczne badania stanu uplastycznienia materiału idealnie plastycznego w otoczeniu karbu

100%

Buczyński A. , Grudziński J.

Przegląd Mechaniczny

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2007

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tom nr 9

26-34

PL

Celem pracy jest analiza stanów naprężenia i odkształcenia, jakie powstają w strefie materiału otaczającego dno karbu w wyniku działania niesymetrycznych obciążeń cyklicznych. Rozpatrywane zagadnienie obejmuje analizę zachowania się dwuwymiarowej płyty, z poziomą szczeliną środkową, pracującej w płaskim stanie odkształcenia w wyniku niesymetrycznego obciążenia działającego w powtarzalnych cyklach. Rozważania prowadzone w dziedzinie małych deformacji, dla stali miękkiej ST37, z uwzględnieniem założeń cyklicznego modelu idealnej plastyczności, stanowią kontynuację pracy odnoszącej się do analizy uplastycznienia stali SAE4140, reprezentującej klasę materiałów ze wzmocnieniem.

EN

Reliability and fatigue life estimation of structural and mechanical components exercising multiaxial loads need predictions of evolution of stress and strain fields. The solution of the problem demands high accuracy regarding stress-strain distribution especially in zones affected by stress concentrators such as cracks, geometrical or structural notches etc. The paper is addressed to numerical analysis of material plastic flow near the root of the U-type notch, located in a plate made of ST37 steel under non-symmetric cyclilc loads. The FEM will be applied to solve the problem formulated in 2D space. The material behavior will be predicted by using the ideal plasticity cyclic model.

10

Identyfikacja modelu na potrzeby diagnostyki technicznej

100%

Dziurdź J.

Przegląd Mechaniczny

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2007

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tom nr 11

47-49

PL

Przedstawiono propozycję postępowania w zadaniu identyfikacji modeli dla celów diagnostyki technicznej. Zwrócono uwagę na uzależnienie stopnia skomplikowania modelu od tego, jakiemu celowi ma on służyć. Wywody - poparte prostymi przykładami analizy pracy łożyska kulkowego - podsumowuje stwierdzenie, że budowa hierarchiczna modeli, od tych prostych do tych bardziej skomplikowanych, umożliwia prostą identyfikację podstawowych parametrów oraz weryfikację wyników działania modeli o różnym stopniu skomplikowania (większe prawdopodobieństwo uniknięcia grubych błędów).

EN

There were presented proposal of procedure in task of models identification for the technical diagnostic. The attention was given on dependence of complication level of the model depending on its appropriation and possibilities of identification. Arguments - supported by simple examples of analysis of ball bearing work - summarizes statement that hierarchical structure of models, from these simple to more complicated enables simple identification of basic parameters and verification of models functioning (with different level of complication) - greater probability to avoid of gross errors.

11

Numeryczne aspekty modelowania układu lufa-pocisk

100%

Łazowski J. , Małachowski J.

Przegląd Mechaniczny

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2007

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tom nr 6

33-38

PL

Projektowanie uzbrojenia w dużej mierze opiera się na metodach analitycznych, które obecnie nie pozwalają na znaczną poprawę parametrów broni. Szczególnie istotna jest analiza dynamiki dla ruchu pocisku w lufie na stożku przejściowym i ustalenie optymalnych parametrów procesu. W pracy przedstawiono próbę analizy stanu wytężenia powstającego podczas szybkozmiennych procesów w trakcie współpracy pocisku z lufą. Przedstawiono model numeryczny obiektów i zaprezentowano wyniki analizy w formie planów warstwicowych. Narzędziem zastosowanym do analizy był pakiet obliczeniowy LS-DYNA umożliwiający symulacje w zakresie nieliniowym z jawnym krokiem całkowania.

EN

Design of armament, in large measure, is based on analytical methods, which at present not allowed for considerably improvement of armament parameters. Especially essential is analysis of motion dynamics of missile in the barrel on transient cone and establishment optimum parameters of the process. In the work, attempt of effort state analysis during rapidly variable processes under conditions of barrel-missile interaction was presented. Numerical model of the objects was shown as well as results of analysis in the form of contour line plans. The tool applied in analysis was analytical package LS-DYNA enabled simulations in the nonlinear range with over integration step.

12

Hierarchical Hidden Markov Models for User/Process Profile Learning

100%

Galassi U. , Botta M. , Giordana A.

Fundamenta Informaticae

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2007

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tom Vol. 78, nr 4

487-505

EN

This paper presents an algorithm for automatically constructing sophisticated user/process profiles from traces of their behavior. A profile is encoded by means of a Hierarchical Hidden Markov Model (HHMM), which is a well formalized tool suitable to model complex patterns in long temporal or spatial sequences. A special sub-class of this hierarchical model, oriented to user/process profiling, is also introduced. The algorithm follows a bottom-up strategy, in which elementary facts in the sequences (motifs) are progressively grouped, thus building the abstraction hierarchy of a HHMM, layer after layer. The method is firstly evaluated on artificial data. Then a user identification task, from real traces, is considered. A preliminary experimentation with several different users produced encouraging results.

13

Structural modelling with Petri nets

100%

Bluemke I.

Foundations of Computing and Decision Sciences

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1998

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tom Vol. 23, No. 1

3-13

EN

An example of structural modelling with Petri nets with refinements is discussed. A simple assembly line consisting of two machines is considered. The assembly line model is made more precise by refining each transition representing the machine, by the Petri net defining its operation. The Petri net model of the assembly line is used as a building block while modelling an entire factory unit. The descriptions of all Petri nets used are given in the new high-level language.

14

Adsorptive properties of natural water surfactant films. Dead Vistula catchment water studies

80%

Pogorzelski S. J. , Kogut A. D.

Oceanologia

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2003

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tom No. 45 (3)

373-394

EN

The paper contains the results of natural film experiments carried out on inland waters in the Dead Vistula (Martwa Wisła) catchment area during 1999-2002 using the integrated Langmuir trough-Wilhelmy plate system, which "cuts out" an undisturbed film-covered area without any physicochemical sample processing. The static film parameters result from the generalized scaling procedures applied to the surface pressure-area isotherms. They appear to correspond well to observations of the film composition Alim, MW, Eisoth, film solubility and the miscibility of its components (via R, ΔSc and y factors), and surface concentration Πeq, Γeq. A novel approach is presented for the adsorption dynamics on the basis of the mixed kinetic-diffusion model and analyses of the dynamic surface pressure plots, which leads to the determination of the effective relative diffusion coefficient Deff / D and activation energy barrier Ea / RT. There is reason to believe that certain classes of film-forming components or "end-members" may dominate the static and dynamic surface properties. Some of these substances can be used as source-specific surface-active biomarkers to trace temporal and spatial changes due to environmental factors or the production of biological matter. The concept was tested for the Dead Vistula river and its tributaries. The results demonstrate that natural films are a complex mixture of biopolymeric molecules covering a wide range of solubilities, surface activities and molecular masses with an apparent structural film architecture. Such studies could lead to the development of film structure parameters - indicators of ecosystem quality and the state of the environment.

15

The changing North Sea: knowledge, speculation and new challenges

80%

Sündermann J.

Oceanologia

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2003

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tom No. 45 (2)

247-259

EN

Synthesis and New Conception of North Sea Research (SYCON) is the title of a German project carried out from 1998-2000 under the leadership of Hamburg University 1. It was accompanied by an international advisory board and covered North Sea issues as well as the general challenges to shelf sea research and sustainable management under global change. Particular emphasis was placed on the interdisciplinary analysis of comprehensive areas of knowledge: the data situation, understanding of processes, model development, instruments and methods, understanding of the system. Based on this, perspectives for future North Sea research were developed. The project produced a synthesis report, eleven monodisciplinary reports and an illustrated brochure for the general public (see Annex 1, this paper, p. 258).

16

Hydrodynamic modelling in the Polish Zone of the Baltic Sea - an overview of Polish achievements

80%

Jasińska E. , Robakiewicz M. , Staśkiewicz A.

Oceanologia

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2003

|

tom No. 45 (1)

107-120

EN

This paper gives a general overview of Polish experience and achievements with regard to hydrodynamic modelling in the Polish zone of the Baltic Sea. The first work started already at the end of the sixties when the first 1D and 2D hydrodynamic models were set up. With the development of numerical methods and increasing computational power a number of 1D, 2D and 3D models were set up and tested. Global, regional and local models cover the most important water bodies, i.e. the Pomeranian Bay - Szczecin Lagoon and Gulf of Gdansk - Vistula Lagoon systems.

17

Modelling the material uptake and deposition of the mytilus edulis in the Baltic coastal ecosystem

80%

Zemlys P. , Daunys D. , Razinkovas A.

Oceanological and Hydrobiological Studies

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2003

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tom Vol. 32, No. 2

53-79

EN

A model was developed to describe the material uptake and biodeposition of bivalve Mytilus edulis. The existing blue mussel organism level models are based on contradictory assumptions and no agreement has still been found regarding the processes and environmental factors to be included into the model. A reconciliation of contradictory approaches was successfully done in the present model. Using seston concentration, seston organic content and mussel size as input data, the model is able to predict the uptake of suspended material, selection of organic particles and material allocation as pseudofaeces, ingested, assimilated fractions and faeces. The results of the model application to mussels in the south-eastern Baltic conditions are discussed.

18

Główne aspekty modelowania zrobotyzowanego stanowiska roboczego.

80%

Nieoczym A.

Technologia i Automatyzacja Montażu

|

2002

|

tom nr 4

12-20

19

On modelling of medium thickness plates with a uniperiodic structure

80%

Baron E.

Journal of Theoretical and Applied Mechanics

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2002

|

tom Vol. 40 nr 1

7-22

EN

The aim of this contribution is to propose a new averaged 2D-model of non-homogeneous Reissner-Mindlin elastic plates with one-directional periodic structure. So far, the averaged 2D-models of periodic plates were formulated on the basis of the known asymptotic homogenization theory in the framework of which the effect of repetive cell size on the overall plate behaviour is neglected. To remove this drawback the tolerance averaging of the plate equations was applied, cf. Woźniak and Wierzbicki (2000). It is shown that the aforementioned cell size effect plays an important role not only in dynamic problems (like for plates with two-directional periodic structure) but also in the quasi-stationary and stability problems. The obtained results are compared with those derived for the plates having a periodic structure in two directions as well as for the plates described in the framework of homogenization.

PL

Modelowanie średniej grubości płyt o strukturze uniperiodycznej. Celem pracy jest przedstawienie nowego, uśrednionego dwuwymiarowego modelu niejednorodnych, średniej grubości (wg hipotezy Reissnera-Midlina) liniowo-sprężystych płyt o jednokierunkowej strukturze periodycznej. Dotychczas zagadnienia płyt tego typu były najczęściej rozwiązywane metodą homogenizacji asymptotycznej. Metoda ta pomija jednak wpływ powtarzalnego segmentu płyty na jej makromechaniczne własności. Dlatego też zastosowano metodę uśredniania tolerancyjnego równań płyty, która ten wpływ uwzględnia, a opisana jest np. przez Woźniaka i Wierzbickiego (2000). Wpływ wymiaru powtarzalnego segmentu płyty odgrywa istotną rolę nie tylko w dynamice, ale również w niektórych zagadnieniach quasi-stacjonarnych i zagadnieniach stateczności. Uzyskane równania porównano z równaniami wyprowadzonymi tą samą metodą modelowania dla płyt o średniej grubości o dwukierunkowej strukturze periodycznej oraz z modelem zhomogenizowanym asymptotycznie

20

On the dynamic behaviour of uniperiodic folded plates

80%

Michalak B.

Journal of Theoretical and Applied Mechanics

|

2002

|

tom Vol. 40 nr 1

113-128

EN

The aim of the contribution is to formulate an averaged model describing the dynamic behaviour of periodically folded shell-like structure, called a folded plate. The contribution proposes new approach to the modelling one-dimensional periodic structure. The characteristic feature of the proposed model is that it makes possible to take into account the effect of periodicity cell size on the dynamic behaviour of the periodic structure. It will be shown that the dynamic behaviour of the plate with one-dimensional periodic structure cannot be treated as a specific case of dynamics of the plate with two-dimensional periodic structure. The main drawback of most of the existing averaged models for periodic structure is that only averaged boundary conditions can be described. On the basis of the proposed model, a more general displacement boundary conditions in the mezo-scale (in the region of the periodicity cell) can be defined.

PL

Celem pracy jest otrzymanie uśrednionego modelu opisującego dynamiczne zachowanie się płyt jednokierunkowo periodycznych zbudowanych z tarczownicowych elementów powłokowych. Rozważania oparte są na metodzie uśredniania tolerancyjnego przedstawionej w pracy Woźniaka i Wierzbickiego (2000). Otrzymane równania uwzględniają efekt skali, co pozwala opisać zjawiska dyspersji. Przedstawiony model pokazuje, że dynamika płyty jednokierunkowo periodycznej nie może być traktowana jako szczególnyprzypadek płyty o strukturze dwukierunkowo periodycznej. Wadą większości istniejących uśrednionych modeli struktur periodycznych jest to, że pozwalają one na zapisanie warunków brzegowych tylko dla wartości uśrednionych. Proponowany model pozwala zapisać na brzegach prostopadłych do kierunku periodyczności warunki brzegowe dla pól całkowitych, a nie tylko dla ich uśrednionych części.