Random packing of regular polygons and star polygons on a flat two-dimensional surface

Random packing of unoriented regular polygons and star polygons on a two-dimensional flat, continuous surface is studied numerically using random sequential adsorption algorithm. Obtained results are analyzed to determine saturated random packing ratio as well as its density autocorrelation function. Additionally, the kinetics of packing growth and available surface function are measured. In general, stars give lower packing ratios than polygons, but, when the number of vertexes is large enough, both shapes approach disks and, therefore, properties of their packing reproduce already known results for disks.Comment: 5 pages, 8 figure

Domain structure created by irreversible adsorption of dimers

Structure of monolayers built during adsorption process is strongly related to the properties of adsorbed particles. The most important factor is their shape. For example, adsorption of elongated molecules on patterned surfaces may produce certain orientational order inside a covering layer. This study, however, focuses on random adsorption of dimers on flat, homogeneous surfaces. It has been observed that despite the lack of global orientational ordering, adsorbed dimers may form local, orientationally ordered structures [1, 2]. Our investigations focus on the dependence between domain size distribution and environmental parameters such as ionic strength, which affects the range of electrostatic interaction between molecules.Comment: 8 pages, 5 figures, Presented at the XXV Marian Smoluchowski Symposium on Statistical Physics, Krak\'ow, Poland, September, 201

Random sequential adsorption of trimers and hexamers

Adsorption of trimers and hexamers built of identical spheres was studied numerically using the Random Sequential Adsorption (RSA) algorithm. Particles were adsorbed on a two dimensional, flat and homogeneous surface. Numerical simulations allow to establish the maximal random coverage ratio, RSA kinetics as well as the Available Surface Function (ASF), which is crucial for determining kinetics of the adsorption process obtained experimentally. Additionally, the density autocorrelation function was measured. All the results were compared with previous results obtained for spheres, dimers and tetramers.Comment: 11 pages, 6 figure

Competitive adsorption of bimodal latex suspension

Competitive deposition of binary mixture of small and large latex particles is studied using Random Sequential Adsorption (RSA) algorithm. We designated the saturated random coverage ratio dependence on small-to-large particle concentration ratio and on particles size ratio. Moreover, the deposition kinetics of the process was calculated numerically. To check validity of the numerical model, the saturated random coverage ratio for 1:1 binary latex particle mixture was measured experimentally using Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM)

Molecular dynamics simulation of the Lennard-Jones polymers in a good solvent

We carried out united-atom Langevin dynamics simulations of poly- mer’s equilibrium state in a good solvent. Our primary goal was a pedagog- ical exposition of fundamental equilibrium properties of isolated polymers in dilutions with amodel that containsmany features of realmaterials. The polymer was chosen to be a three-dimensional chain of N identical beads (monomers) without internal structure. Each monomer interacted with its two neighbors by a harmonic potential, which modeled a chemical bond. Additionally all monomers within a chain were assumed to interact through the Lennard–Jones (LJ) potential. Interaction with solvent and with other polymers was introduced using Langevin forces. Analyzing internal energy per polymer and radius of gyration as function of temperature we observed a rapid globule to coil phase transition. Also we studied elastic properties of single polymer chain for temperatures below the transition and identified three regions with different elastic behavior. Typical chain lengths in our simulations ranged from 100 to 1000 monomers. The elaborated software package can easily be modified to study e.g. the effect of polymer stiffness on thermodynamic behavior

Random packing of spheres in Menger sponge

Random packing of spheres inside fractal collectors of dimension 2 < d < 3 is studied numerically using Random Sequential Adsorption (RSA) algorithm. The paper focuses mainly on the measurement of random packing saturation limit. Additionally, scaling properties of density autocorrelations in the obtained packing are analyzed. The RSA kinetics coefficients are also measured. Obtained results allow to test phenomenological relation between random packing saturation density and collector dimension. Additionally, performed simulations together with previously obtained results confirm that, in general, the known dimensional relations are obeyed by systems having non-integer dimension, at least for d < 3.Comment: 13 pages, 6 figure

Post-Covid perspectives for the automotive industry, opportunities, and threats

The subject of the study is to verify the impact of the SARS-COV2 virus pandemic on the functioning of the automotive industry in the context of the global economy. The conducted research is important due to the enormous change in the functioning of the automotive industry due to the covid pandemic as well as megatrends affecting the industry. The paper aims to verify the determinants influencing the functioning of the automotive industry. The conclusions resulting from the study will be used to better understand the current situation and to prepare the market's strategy for the coming years. The selected research method includes literature and industry research and the Exact Systems company case study. The case study relates to a survey of car and car parts manufacturers in 12 European countries. The author's contribution is an indication of many factors influencing the potential future of the automotive industry available in the literature. Then the author compares these data with the expectations and predictions of the car manufacturers' market participants to draw consistent conclusions

The theory and practice of testing the quality ofoutsourcing services in the automotive industry

In the automotive industry, it is common practice to outsource additional processes to external companies. Outsourced processes have to be evaluated. The practice and theory related to researching the quality of services and the level of customer satisfaction in the literature are well and wide described. However, in practice, the automotive industry does not use known solutions but applies its own criteria and methods for assessing the quality of outsourcing services and testing the level of customer satisfaction. The article is an attempt to analyse the solutions used in this area in the automotive industry and to indicate the strengths and weaknesses of the solutions used. Paper includes SWOT studies for a practical example of a used customer satisfaction test. Potentials for improvement are defined

The Civic budget as a form of participation at the local level and its evaluation on the example of Cracow

Celem pracy jest omówienie problematyki związanej z funkcjonowaniem budżetu obywatelskiego w polskich warunkach prawno-politycznych posługując się analizą procesów realizacji funduszu partycypacyjnego w Krakowie. Pierwszy i drugi rozdział pracy zawiera teoretyczne tło dalszych rozważań. W celu przygotowania oceny i rekomendacji zmian użyto trzech pogłębionych wywiadów, oraz ankiety. Procedury realizacji, ocena i rekomendacje zawarte są w III rozdziale pracy. Z wyników badania można wysnuć tezę, że obywatele nie są zadowoleni z realizacji budżetu obywatelskiego w Krakowie. Każdy z etapów realizacji przebiega w nieodpowiedni sposób i aby stał on się istotnym narzędziem partycypacji należy do systemu funkcjonowania wprowadzić zmiany. W szczególności badaniu poddane zostały opinie osób zajmujących się na co dzień realizacją przedsięwzięcia oraz zwykli mieszkańcy, którym badane narzędzie ma dać możliwość czynnego uczestnictwa w życiu społeczno – politycznym miasta. Szczególnie istotne znaczenie dla pracy miały głosy krytyczne odnoszące się do budżetu obywatelskiego w Krakowie.The purpose of the study is to discuss issues related to functioning of the civic budget in Polish political and legal conditions using the analysis of the process of implementation a participatory budgeting in Cracow. In particular, the reviews from people who deal with the project on a daily basis as well as the opinions of ordinary residents to whom the tested tool is supposed to give the opportunity to participate actively in the social and political life have undergone a thorough examination. All the critical voices relating to the civil budget had a great significance for the work.The first and the second chapter of the work contain the substantive foundation of further deliberations. In order to prepare the evaluation and recommendation of changes three in-depth interviews and surveys have been used. Procedures of the implementation, assessment and recommendation are included in the third chapter. From the results of the study it can be concluded that the citizens are not satisfied with the implementation of the budget in Cracow. None of the stages of implementation proceed properly and some amendments need to be done in order to create an essential tool of participation

Zaawansowane rozszerzenia dla eksperymentalnego algorytmu parsowania Alt.Parser.

Alt.Parser jest eksperymentalnym projektem programistycznym, którego celem jest rozwijanie algorytmu parsowania Adaptive LL(*), wprowadzonego przez ANTLR 4. W ramach poniższej pracy zaimplementowano efektywniejszą alternatywę dla struktury danych wykorzystywanej w kluczowych miejscach programu, oraz dwa rozszerzenia zwiększające elastyczność sposobu definiowania gramatyk.Alt.Parser is an experimental software project, investigating extending the Adaptive LL(*) parsing algorithm, employed by ANTLR 4. This work consists of a few important contributions to the project: one, engineering a more efficient alternative to a heavily used data structure, and two other, improving the flexibility of grammar definitions