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The paper presents a developed computational model based on decision- random models, which allows us to develop a strategy for preventive renewal of complex technical objects whose maintenance activities cover various actions. Depending on the renewal type, diversification of the cost and maintenance time may influence the interval at which preventive renewal should be performed. The developed algorithm takes into account the predicted time of proper operation based on the probability distribution of operating time to failure, as well as the cost of each preventive action and potential failure. The defined strategy is a set of activities that must be performed every specified time interval in a manner that is economically justified and minimizes the risk of failure. The technical object on which the model is discussed is the wheel tyre of a rail vehicle.

The aim of the work was to develop a method of verification of the preventive renewal strategies, which enables a simulation evaluation of the effects of the application of a specific schedule of inspections of parts that are important in the operation of complex renewable technical objects. Using it requires having an already established schedule of inspections, and the result of applying the method is determined by indicators that assess the usefulness of the strategy, even before implementation. The developed computational tool was used to evaluate the renewal strategy of the current collector contact plates. Based on the real operational data, several renewal intervals were considered, determining the frequency of events involving the plate covering a specific mileage, from exceeding the wear control limit value to the next inspection (replacement). The proposed verification method is an important tool for testing and planning technical inspections for systems and elements with planned wear, and parts are periodically replaced.

The paper presents the developed simulation model enabling the evaluation of the reliability of technical objects, which in the process of operation is subjected to several different groups of factors causing their failures. Probability distributions of failures resulting from wear and random factors are used in the developed model to estimate the time of operation of the elements and the reliability of the system. The developed model together with the appropriate computer program is a tool of significant importance for design and operational practice. It enables decision-makers to estimate the reliability of elements and the whole system before the beginning of their operation.

Generation of well-defined organic-inorganic hybrid materials with controllable size and morphology is challenging and an active area of modern research in view of their unique properties and thus multifunctional applications. Specifically polyoxometalates (POMs) were recognized as a very promising group for the construction of those systems, nonetheless there are domains where the profound understanding of hierarchical mutual interactions and assembly are lacking. We present an efficient approach towards the synthesis of a novel group of POM-based nanocomposites that we name Complex-Decorated Surfactant Encapsulated-Clusters (CD-SECs). In the investigated system the organic surfactant may behave as a metal-coordinating agent, thus allowing for derivatization of the synthesized SECs via utilization of the non-covalent interactions. We demonstrate possibilities and limitations of three types of hybrid systems (H1-H3) generated via seven distinct constructing approaches (routes A-G). These systems have the potential to exhibit multiresponsive functions depending on the nature of their building blocks and could find many potential applications in biology or materials science.

The paper presents issues concerning the implementation of particle size analyzers in the evaluation of the grinding product. A review of the current solutions of the analyzers used in practice was made. The usefulness of the original size analysis system according to its own design has been verified and exemplary results of the size assessment of grinding products - polymeric materials and biological materials have been presented.

The publication presents selected results of an attempt to link material and environmental valuation with the design of technical objects in accordance with the requirements of the concept of Life Cycle Management. The goal of this action was to develop environmental analysis of the conical shredder using the SolidWorks Sustainability application. The assessment of environmental impacts included: extraction of raw materials, material processing, production of parts, assembly, use of the product, landfill storage and transport. Based on the results of the analysis, the potential emission levels were determined: CO2, SO2, PO4 and guidelines for the environmental development of technical facilities were proposed.

Comminution processes are one of the most common processes for processing energy materials, e.g. coal, biomass, and post-recycling elements. The hitherto unsolved problem is the high energy consumption of machines and the lack of precise descriptions of the phenomenon of comminution in terms of the relationship between the design features of mills and the properties of comminuted materials. The dynamic development of simulation techniques based on advanced models and the method of discrete elements allows for a certain mapping of occurring phenomena. The purpose of the work is to illustrate the possibility of using simulation software based on the discrete element method to model the grinding processes in the shredders grinding assemblies. The paper presents aspects of modeling the shape and size of particles, their interactions and contacts with mills structural elements, as well as aspects of crushing modeling in RockyDem software.

The paper presents the opportunities for the adjustment of operating parameters and constructional parameters of shredders for polymer materials using CAD/CAE tools. The object of research is a conical shredder developed on the basis of a patent. For studies SolidWorks application with simulation and motion option has been used.

The STAR-FLOOD (Strengthening and Redesigning European Flood Risk Practices Towards Appropriate and Resilient Flood Risk Governance Arrangements) project, funded by the European Commission, investigates strategies for dealing with flood risk in six European countries: Belgium, the UK, France, the Netherlands, Poland and Sweden and in 18 vulnerable urban regions in these countries. The project aims to describe, analyse, explain, and evaluate the main similarities and differences between the selected EU Member States in terms of development and performance of flood risk governance arrangements. It also discusses the scientific and societal importance of these similarities and differences. Attention is paid to identification and characterization of shifts in flood risk governance arrangements and in flood risk management strategies and to determination of triggering factors and restraining factors. An assessment of a change of resilience and appropriateness (legitimacy, effectiveness, efficiency) of flood risk governance arrangements in Poland is presented and comparison with other European countries is offered.

Contains fulltext : 162761pub.pdf (Publisher’s version ) (Open Access) Flood events that have proven to create shock waves in society, which we will call shock events, can open windows of opportunity that allow different actor groups to introduce new ideas. Shock events, however, can also strengthen the status quo. We will take flood events as our object of study. Whereas others focus mainly on the immediate impact and disaster management, we will focus on the long-term impact on and resilience of flood risk governance arrangements. Over the last 25 years, both the Netherlands and Poland have suffered several flood-related events. These triggered strategic and institutional changes, but to different degrees. In a comparative analysis these endogenous processes, i.e., the importance of framing of the flood event, its exploitation by different actor groups, and the extent to which arrangements are actually changing, are examined. In line with previous research, our analysis revealed that shock events test the capacity to resist and bounce back and provide opportunities for adapting and learning. They “open up” institutional arrangements and make them more susceptible to change, increasing the opportunity for adaptation. In this way they can facilitate a shift toward different degrees of resilience, i.e., by adjusting the current strategic approach or by moving toward another strategic approach. The direction of change is influenced by the actors and the frames they introduce, and their ability to increase the resonance of the frame. The persistence of change seems to be influenced by the evolution of the initial management approach, the availability of resources, or the willingness to allocate resources. 15 p.

In Poland floods are the predominant natural disasters entailing large losses. In the paper it is presented how flood risk management is organized in Poland, and how the approaches to flood risk in the country evolve. The focus is on organisation of flood risk management. Public policies and activities of public administration are analysed. Based on data collected within the EU 7th Framework Project STAR-FLOOD, the description of the Polish Flood Risk Management Strategies and Governance arrangements is provided. Next, the dynamics of the Polish flood risk management strategies and governance arrangements and evaluation of arrangements are presented. The reliance on structural defence is indicated, as a stable component of the floor risk management. Also main factors triggering changes and four main turning points opening windows of opportunity for Polish flood management system are identified: two of them are related to socio-political development and two to flood event. The Polish flood risk management system has experienced changes (i.e. establishment of a new crisis management system), while preserving its core functional characteristics at the same time (reliance on structural defence). Sectorial management with little coordination at the level of ministries renders the flood risk management in Poland being more like bargain and competition than collaborative and consensus-driven type of governance. The Polish Flood Risk Governance Arrangement is characterised as having a strong capacity to buffer shock events, as shown by the major 1997 and 2010 floods. An overall weakness of the Polish Arrangement is the lack of coordination and strategic management. Problems with effective spatial planning and a highly fragmented actors structure both within and between sub-arrangements are the main challenges for the Polish flood risk management.

Contains fulltext : 159332.pdf (Publisher’s version ) (Open Access) Across Europe, citizens are increasingly expected to participate in the implementation of flood risk management (FRM), by engaging in voluntary-based activities to enhance preparedness, implementing property-level measures, and so forth. Although citizen participation in FRM decision making is widely addressed in academic literature, citizens’ involvement in the delivery of FRM measures is comparatively understudied. Drawing from public administration literature, we adopted the notion of “coproduction” as an analytical framework for studying the interaction between citizens and public authorities, from the decision-making process through to the implementation of FRM in practice. We considered to what extent coproduction is evident in selected European Union (EU) member states, drawing from research conducted within the EU project STAR-FLOOD (Strengthening and Redesigning European Flood Risk Practices towards Appropriate and Resilient Flood Risk Governance Arrangements). On the basis of a cross-country comparison between Flanders (Belgium), England (United Kingdom), France, the Netherlands, and Poland, we have highlighted the varied forms of coproduction and reflected on how these have been established within divergent settings. Coproduction is most prominent in discourse and practice in England and is emergent in France and Flanders. By contrast, FRM in the Netherlands and Poland remains almost exclusively reliant on governmental protection measures and thereby consultation-based forms of coproduction. Analysis revealed how these actions are motivated by different underlying rationales, which in turn shape the type of approaches and degree of institutionalization of coproduction. In the Netherlands, coproduction is primarily encouraged to increase societal resilience, whereas public authorities in the other countries also use it to improve cost-efficiency and redistribute responsibilities to its beneficiaries. 14 p.

An improved method for peptide sequencing based on acetylation/deuteroacetylation in conjunction with ESI MS is introduced. Derivatization with a 1:1 mixture of acetic anhydride and deuterated acetic anhydride incorporates a stable isotope label into the analyzed molecule. This approach has been initially applied to FAB. Using MS/MS, the technique provides a fast, highly sensitive and reliable determination of the primary structure of unknown peptides. This procedure labels N-terminal fragments formed during MS/MS analysis, resulting in a simplification and faster interpretation of the spectra. The performance of the method has been tested with several synthetic peptides and applied to an efficient sequencing of the peptide map, using a nano-scale LC coupled on-line to a tandem mass spectrometer.

A linear-scaling implementation of the elongation cutoff technique (ELG/C) that speeds up Hartree-Fock (HF) self-consistent field calculations is presented. The cutoff method avoids the known bottleneck of the conventional HF scheme, that is, diagonalization, because it operates within the low dimension subspace of the whole atomic orbital space. The efficiency of ELG/C is illustrated for two model systems. The obtained results indicate that the ELG/C is a very efficient sparse matrix algebra scheme.

Pokazano, że technika obcięcia zastosowana w metodzie wydłużania istotnie przyspiesza obliczenia kwantowo-chemiczne w formaliźmie Hartreego-Focka (HF). Metoda ta sprawdza się wyjątkowo dobrze w obliczeniach przeprowadzanych na wielu procesorach. W pracy porównano zarówno całkowity czas obliczeń, jak i jego najbardziej czasochłonnych części, z tradycyjnym schematem obliczeniowym metody HF. It is demonstrated that the elongation cutoff technique (ECT) substantially speeds up the quantum-chemical calculation at Hartree-Fock (HF) level of theory and is especially well suited for parallel performance. A comparison of ECT timings for water chains with the reference HF calculations is given. The analysis includes the overall CPU (central processing unit) time and its most time consuming steps.