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1
EN
Purpose: The purpose of the paper is to present the concept of providing organizational structure with necessary stability and variability. Design/methodology/approach: The concept draws from the results of a case study on the Society of Jesus (Jesuits), an organization that dates back to the first half of the sixteenth century, whose leaders assure great adaptive capacity, as well as stability and identity at the same time. Findings: The article sheds light on combining stability and variability during the structuring of organizations and presents a new approach, which builds on the principles of continuity and simplicity. Originality/value: Unlike the well-known organization life cycle models, which consider the organizational structure as a relatively stable element, that is subject to significant transformations when progressing through the life cycle phases, the presented concept favors evolutionary development of structures based on dynamic focusing of continuity and simplicity. The simultaneous observance of both principles has not yet been presented in the literature.
2
Content available remote Inhomogeneity detection in phytoplankton time series using multivariate analyses
EN
Phytoplankton communities have long been used as water quality indicators within environmental policies. This has fostered the development of national and international phytoplankton monitoring programs, but these networks are subject to sources of uncertainty due to laboratory issues. Nevertheless, studies regarding the interference associated with these aspects are not well-documented. Hence, a long time series (2003-2015) from the Basque continental shelf (southeastern Bay of Biscay) was analyzed to evaluate the uncertainty given by laboratory strategies when studying phytoplankton variability. Variability in phytoplankton communities was explained not only by environmental conditions but also by changes in fixatives (glutaraldehyde and acidic Lugol's solution) and laboratory staff. Based on Bray-Curtis distances, phytoplankton assemblages were found to be significantly dissimilar according to the effect of changes in the specialist handling the sample and the employed fixative. The pair-wise permutational multivariate analysis of variance (PERMANOVA) showed significant differences between the two fixatives utilized and also between the three taxonomists involved. Thus, laboratory-related effects should be considered in the study of phytoplankton time series.
EN
Knowledge of the way in which minor and trace elements occur in coal is one of the most important geochemical indicators of coal quality. The differences between the methods of binding elements in coal in each coal seam and the variability of this feature of coal in the basin profile have not been discussed so far. These coal features were identified in a group of selected coal seams (209, 401, 405, 407, 501, 504, 510, 615, 620) in the Upper Silesian Coal Basin (USCB). At the same time, the differences in the role of identified mineral and maceral groups in concentrating specific elements in coal is highlighted. Identical or similar tendencies of changes in the way in which As and V, Ba and Rb, Co and Pb, Co and Zn, Mn and Pb, Pb and Zn, Co and Rb, and for Cr and Cu occur in the coal seams in the USCB profile was found. Changes in the mode of occurrence of As and Pb in coal in the USCB profile were probably influenced by carbonate mineralization. The changes in the mode of occurrence of Mni and Pb in the coal were probably determined by dia and epigenetic sulfide mineralization, while the content of Ba, Cr, Rb, Sr, and V in coal from these deposits was affected by clay minerals. It was observed that the greater the degree of the carbonization of the organic matter of coal, the lower the content of As, Mn and Pb in coal and the higher the content of Ba and Sr in coal.
PL
Wstęp: W artykule przedstawiono koncepcję sterowania systemem produkcyjnym, pozwalającą na zachowanie jego stabilności, a tym samym na realizację założonych planów produkcyjnych. W tym celu zaproponowano połączenia modeli symulacyjnych i modeli sztucznych sieci neuronowych (SSN) systemu produkcyjnego. Połączenie obydwu typów modeli było możliwe dzięki opracowaniu hybrydowego modelu systemu ekspertowego do oceny możliwości realizacji planu produkcji (celu) w zależności od wielkości ryzyka i poziomu stabilności analizowanego systemu produkcyjnego. Analizowany problem - możliwość realizacji planów produkcyjnych w zależności od wielkości ryzyka i poziomu stabilności systemu produkcyjnego - jest trudny do zamodelowania matematycznego. Jednak na podstawie analizy danych, pochodzących z modelu symulacyjnego i modelu ANN, można uzyskać informacje dotyczące zależności odpowiadających sobie wartości wejściowych i wyjściowych. Metody: Na podstawie przedstawionego sposobu zarządzania procesu produkcyjnego z wykorzystaniem modeli komputerowych, przeanalizowano możliwości zastosowania modeli symulacyjnych i modeli ANN w ocenie stabilności i ryzyka systemów produkcyjnych. Dokonano analizy i porównania obydwu typów modeli ze względu na sposób budowy oraz rodzaj danych wejściowych i wyjściowych. Wyniki: Na bezpośrednie połączenie modeli symulacyjnych i modeli SSN nie pozwala ich odmienna budowa, specyfika oraz inne rodzaje danych wejściowych i wyjściowych. Dlatego prezentowana w artykule koncepcja fuzji obydwu typów modeli odbywa się poprzez bazę wiedzy eksperckiej i wnioskowanie rozmyte. Wnioski: Na potrzeby sterowania systemem produkcyjnym, zaproponowano budowę hybrydowego modelu systemu ekspertowego do oceny możliwości realizacji celu w zależności od wielkości ryzyka i poziomu stabilności systemu produkcyjnego.
EN
Background: Control plays the main role in ensuring the stability of production processes, while digital models of processes and methods of artificial intelligence are used more and more commonly in it. Production of highly diversified items in small lots at low inventory levels is characterised by a much lower stability as compared with largelot manufacturing. Additionally, innovations created for items or processes result in disturbances to current work. Although this turbulence is usually momentary, it may lead to a loss of function or manufacturing stability, which in turn translates into financial losses, as well as losing customers. This paper presents the potential of using simulation models and artificial neural network models to assess the stability of a reorganized production system. Methods: The problem analysed in the paper is that of merging a simulation model with an ANN model by designing a hybrid model. A direct connection of both types of models is not possible due to their various structures, specificity, and different purposes, as well as the various types of input and output data. Therefore, the idea of merging these two types of models through an expert knowledge base and fuzzy inference was proposed. The results from the simulation model and the ANN model were used to gather the knowledge on the production system being analysed. It has been proposed that the output from the simulation model provided knowledge of the risk level, while the output from the ANN model provided knowledge of process stability. Results: The paper presents the idea of projecting a hybrid model of the expert system in order to assess the stability of a reorganized production system. A model of a hybrid expert system was developed to assess the potential of executing the assumed production plans. The level of risk and the level of stability determined by the simulation model and the ANN model are entered into the system. The output from the expert model is the value of the variable determining the potential of achieving the goal. In the construction of the model, fuzzy inference was used, which uses linguistic variables and is characterized by a knowledge system in the form of fuzzy rules "if ... then ...". For both the independent variable and for the dependent variable, a set of membership functions representing accepted linguistic variables was proposed, and then decision rules were determined. The idea of merging simulation models with ANN models was tested on a practical example in production system that manufactures products for dishwashers. Conclusions: The potentiality to execute production plans depending on the level of risk and the level of stability of the production system is too complicated to be modelled mathematically, but based on the analysis of data from the simulation and ANN models, it is possible to obtain information concerning the relations between corresponding input and output values.
EN
Modern agriculture foresees the implementation of a particular technological operation, according to the appropriate map-task, which is developed pre-based on diverse information. Knowledge of a certain structure of soil cover variability, obtained using information and technical systems of local operational monitoring of the agrobiological state of agricultural lands, allows us to adopt effective operational decisions for efficient management of agrobiological potential of agricultural lands. Obviously, under such conditions there is a need for fundamentally new approaches to agricultural production, which is to ensure the proper quality of technological operations. The quality of the implementation of technological operations is an integral indicator of the efficiency of production of agricultural products within the agrobiological field. The necessary quality of implementation of the basic technological processes in plant growing is provided by the integrated information and technical systems of operational monitoring of the agrobiological state of agricultural lands. This opens new prospects for organic farming using such smart agricultural machines. In connection with it the task is to obtain reliable data on the agrobiological state of the soil environment by reducing the error in determining the magnitude of the electrical conductive properties of the soil, providing individual stabilization of the working electrodes and the mechanism of lifting / lowering the working electrodes, copying inequalities of the soil environment, reducing the intensity of the destruction of the soil structure , selfcleaning of the working contact of the electrode and ensuring the stability of the electrical contact of the electrode with the soil, by instrument design perfection. The task is achieved by using the information and technical system of operational monitoring of the soil environment of the structure to determine the conductive characteristics of the soil environment. The purpose of the research is to determine the critical loading at the loss of stability by thin-walled working electrodes made in the form of working electrodes of various shapes (thin-walled solid, three-spit and four-spindle discs with different thickness of the rim). The information and technical system of localoperational monitoring of agrobiological state of soil environment of different configurations with one-side compression.
EN
Modern agriculture involves the implementation of a particular technological operation, according to the appropriate map-task, which is developed pre-based on diverse information. Knowledge of a certain structure of soil cover variability, obtained using information and technical systems of local operational monitoring of the agrobiological state of agricultural lands, allows us to adopt effective operational decisions for efficient managemen tagrobiological potential of agricultural lands. Obviously, under such conditions, there is a need for fundamentally new approaches to agricultural production, which is to ensure the proper quality of technological operations. The quality of the implementation of technological operations is an integral indicator of the efficiency of production of agricultural products within the agrobiological field. The necessary quality of implementation of the basic technological processes in plant growing is provided by the integrated information and technical systems of operational monitoring of the agrobiological state of agricultural lands. This opens new prospects for organic farming using such "smart" agricultural machines. In connection with this, the task is to obtain reliable data on the agrobiological state of the soil environment by reducing the error in determining the magnitude of the electrical conductive properties of the soil, providing individual stabilization of the working electrodes and the mechanism of lifting / lowering the working electrodes, copying inequalities of the soil environment, reducing the intensity of the destruction of the soil structure , self-cleaning of the working contact of the electrode and ensuring the stability of the electrical contact of the electrode with the soil, by instrument design perfection. The task is achieved by using the information and technical system of operational monitoring of the soil environment of the structure to determine the conductive characteristics of the soil environment. The purpose of this research is to determine the critical loading at the loss of stability by thin-walled working electrodes made in the form of working electrodes of various shapes (thin-walled solid, three-spit and four-spindle discs with different thickness of the rim). Information and technical system of local-operational monitoring of agrobiological state of soil environment of different configurations with one-side compression.
EN
Modern agriculture involves the implementation of a particular technological operation, according to the appropriate map-task, which is developed pre-based on diverse information. Knowledge of a certain structure of soil cover variability, obtained using information and technical systems of local operational monitoring of the agrobiological state of agricultural lands, allows us to adopt effective operational decisions for efficient management of agrobiological potential of agricultural lands. Obviously, under such conditions, there is a need for fundamentally new approaches to agricultural production, which is to ensure the proper quality of technological operations. The quality of the implementation of technological operations is an integral indicator of the efficiency of production of agricultural products within the agrobiological field. The necessary quality of implementation of the basic technological processes in plant growing is provided by the integrated information and technical systems of operational monitoring of the agrobiological state of agricultural lands. In connection with this, the task is to use a fundamentally new class of information and technical systems of local operational monitoring of the agrobiological state of agricultural lands. The task is achieved by using the information and technical system of operational monitoring of the soil environment of the structure to determine the conductive characteristics of the soil environment. The purpose of this research is to develop and substantiate the functional structure, software, writing code and algorithms for managing the executive bodies of the information and technical system of operational monitoring of the agrobiological state of the soil environment of agricultural lands.
EN
Modern agriculture involves the implementation of a particular technological operation, according to the appropriate map-task, which is developed pre-based on diverse information. Knowledge of a certain structure of soil cover variability, obtained using information and technical systems of local operational monitoring of agro-biological state of agricultural lands, allows us to adopt effective operational decisions for efficient management of agro-biological potential of agricultural lands. Obviously, under such conditions, there is a need for fundamentally new approaches to agricultural production,which is to ensure the proper quality of technological operations. The quality of the implementation of technological operations is an integral indicator of the efficiency of production of agricultural products within the agro-biological field. The necessary quality of implementation of the basic technological processes in plant growing is provided by the integrated information and technical systems of operational monitoring of the agro-biological state of agricultural lands. In connection with this, the task is to obtain reliable data on the agro-biological state of the soil environment by reducing the error in determining the magnitude of the conductive properties of the soil, providing individual stabilization of the working electrodes and the mechanism of lifting / lowering working electrodes, copying inequalities of the soil environment, reducing the intensity of the destruction of the soil structure , self-cleaning of the working contact of the electrode and ensuring the stability of the electrical contact of the electrode with the soil, by instrument design perfection. The task is achieved by using the information and technical system of operational monitoring of the soil environment of the structure to determine the conductive characteristics of the soil environment.
EN
Available techniques for dealing with uncertainties in the agro-industrial complex and their use for describing and assessing the adequacy of the decisions taken are incomplete, and often ineffective, as they usually do not take into account the combination of "field-machine-technological material", which prevents acceptance effective solutions for managing agro-biological potential of agricultural land and, as a consequence, obtaining the maximum economic efficiency of agricultural production. Reliable estimation of variables of agricultural production parameters using the "field-machine-technological material" model makes it possible to provide optimal control of available technical equipment (machinery, sowing machines, etc.), agro-biological (humus content, presence of nutrients, micro-and macro elements, etc. in soil or plant ) and technological resources for making adequate decisions and managing agro-biological potential of agricultural lands, which will provide the necessary economic efficiency. The task is achieved by ensuring the proper quality of the implementation of technological operations that are an integral indicator of economic efficiency and allow providing the necessary economic efficiency through optimal and efficient management of technical means for optimal action on the agro-biological potential of the field and the use of available technological resources. Such control is possible with the use of information and technical systems of local operational monitoring, which are located on machine-tractor units and provide effective control of technological operations by acting on the executive bodies of agricultural machines on the basis of data characterizing the agro-biological state of the soil environment. Information and technical systems of local operational monitoring of the agro-biological state of agricultural lands are used in the following cases: - before performing a technological operation, - simultaneously with the implementation of the technological operation (sowing, fertilizer application, etc.), - during the growing season and after harvesting. This opens new prospects for organic farming using such "smart" agricultural machines.
PL
Celem niniejszego artykułu jest zbadanie zmienności parametrów wytrzymałościowych stali EPSTAL produkowanych w polskiej hucie, tj. granicy plastyczności Re, wytrzymałości na rozciąganie Rm i wydłużenia Agt pod największym obciążeniem, w oparciu o wyniki statycznej próby rozciągania stali próbki wykonane przez producentów w ramach kontroli produkcji fabrycznej. Analiza statystyczna tych wyników wykazała, że zależność napięcia od rozciągania w przypadku próbek stali powinna być opisana przez jednowymiarowy proces stochastyczny i trzy najważniejsze parametry mechaniczne, tj. Re, Rm i Agt według zmiennych losowych.
EN
The purpose of this paper is to examine the variability of strength parameters of EPSTAL steel produced in the Polish steelworks, i.e. yield stress Re, tensile strength Rm, and elongation Agt under the highest load, based on the results of a static tensile test of steel samples made by manufacturers as part of factory production control. Statistical analysis of these results showed that the stress-strain relationship of steel tensile tests should be described by a one-dimensional stochastic process, and the three most important mechanical parameters, i.e. Re, Rm, and Agt by random variables.
11
Content available remote Wykorzystanie georadaru w ocenie podłoża gruntowego
PL
Metoda GPR jest bezinwazyjną techniką dostarczającą informacji o obecności, sposobie i głębokości zalegania obiektów podziemnych oraz o budowie geologicznej badanego terenu. W badaniu wykorzystywane są różnice pomiędzy stałymi dielektrycznymi, odmiennymi dla każdego z analizowanych ośrodków, a wśród czynników niezbędnych do zarejestrowania użytecznego sygnału (informacji) jest wyraźny kontrast pomiędzy stałą dielektryczną poszukiwanego obiektu a jego otoczenia. W artykule pokazano, że technika georadarowa pozwala ustalić nie tylko głębokość zalegania zwierciadła wód gruntowych, ale też zobrazować granice poszukiwanych utworów. Może więc stanowić uzupełnienie tradycyjnych metod in situ, ułepszając tym samym ocenę podłoża gruntowego. Sprawdza się także w lokalizowaniu wszelkiego rodzaju rur, kabli i innych anomalii występujących w podłożu gruntowym.
EN
GPR method is a non-invasive technique for ground exploration which detects subsurface objects and assesses their presence, as well as provides information about the geological structure of investigation site. GPR method takes advantage of the differences between the dielectric constants, specific for the material under analysis. One of the factors that are essential to record reliable data is a clear contrast between the dielectric constant of investigated object and of its surroundings. The paper shows that GPR technique is able to detect not only level of the groundwater table, but also the boundaries of soil layers. Therefore, it may successfully complement traditional in situ methods which considerably improves ground assessment. Moreover, it serves well to identify various kinds of pipes, wires and other anomalies that may be found underground.
EN
Background: The article presents the concept of control of the production system, which allows to maintain its stability, and thus to implement the established production plans. For this purpose, combinations of simulation models and artificial neural network (ANN) models of the production system have been suggested. The combination of both types of models was possible thanks to the development of a hybrid model of the expert system to assess the possibility of implementing the production plan (objective) depending on the risk size and the level of stability of the production system analysed. The analysed problem - the possibility of implementing production plans depending on the risk size and the level of stability of the production system - is difficult to mathematical modelling. However, based on the data analysis from the simulation model and the ANN model, we can obtain information on the dependences of the corresponding input and output values. Methods: Based on the presented method of managing the production process using computer models, the possibilities of using simulation models and ANN models in assessing the stability and risk of production systems have been analysed. The analysis and comparison of both types of models have been performed due to the construction and the type of input and output data. Results: The direct combination of simulation models and ANN models is not allowed by their different structure, specificity and other types of input and output data. Therefore, the concept of combination of both types of models presented in the article is conducted via a database of expertise and fuzzy inference. Conclusions: For the purpose of controlling the production system, it was suggested to build a hybrid model of an expert system to assess the possibility of achieving the objective depending on the risk size and the level of stability of the production systems.
PL
Wstęp: W artykule przedstawiono koncepcję sterowania systemem produkcyjnym, pozwalającą na zachowanie jego stabilności, a tym samym na realizację założonych planów produkcyjnych. W tym celu zaproponowano połączenia modeli symulacyjnych i modeli sztucznych sieci neuronowych (SSN) systemu produkcyjnego. Połączenie obydwu typów modeli było możliwe dzięki opracowaniu hybrydowego modelu systemu ekspertowego do oceny możliwości realizacji planu produkcji (celu) w zależności od wielkości ryzyka i poziomu stabilności analizowanego systemu produkcyjnego. Analizowany problem – możliwość realizacji planów produkcyjnych w zależności od wielkości ryzyka i poziomu stabilności systemu produkcyjnego – jest trudny do zamodelowania matematycznego. Jednak na podstawie analizy danych, pochodzących z modelu symulacyjnego i modelu ANN, można uzyskać informacje dotyczące zależności odpowiadających sobie wartości wejściowych i wyjściowych. Metody: Na podstawie przedstawionego sposobu zarządzania procesu produkcyjnego z wykorzystaniem modeli komputerowych, przeanalizowano możliwości zastosowania modeli symulacyjnych i modeli ANN w ocenie stabilności i ryzyka systemów produkcyjnych. Dokonano analizy i porównania obydwu typów modeli ze względu na sposób budowy oraz rodzaj danych wejściowych i wyjściowych. Wyniki: Na bezpośrednie połączenie modeli symulacyjnych i modeli SSN nie pozwala ich odmienna budowa, specyfika oraz inne rodzaje danych wejściowych i wyjściowych. Dlatego prezentowana w artykule koncepcja fuzji obydwu typów modeli odbywa się poprzez bazę wiedzy eksperckiej i wnioskowanie rozmyte. Wnioski: Na potrzeby sterowania systemem produkcyjnym, zaproponowano budowę hybrydowego modelu systemu ekspertowego do oceny możliwości realizacji celu w zależności od wielkości ryzyka i poziomu stabilności systemu produkcyjnego.
EN
Neuraminidase (NA) is an important protein for the replication cycle of influenza A viruses. NA is an enzyme that cleaves the sialic acid receptors; this process plays a significant role in viral life cycle. Blocking NA with a specific inhibitor is an effective way to treat the flu. However, some strains show resistance to current drugs. Therefore, NA is the focus for the intense research for new antiviral drugs and also for the explanation of the functions of new mutations. This research focuses on determining the profile of variability and phylogenetic analysis and finding the correlated mutations within a set of 149 sequences of NA belonging to various strains of influenza A virus. In this study, we have used the original programs (Corm, Consensus Constructor, and SSSSg) and also other bioinformatics software. NA proteins are characterized by various levels of variability in different regions, which was presented in detail with the aid of ConSurf. The use of four independent methods to create the phylogenetic trees gave some new data on the evolutionary relationship within the NA family proteins. The search for correlated mutations shows several potentially important correlated positions that were not reported previously to be significant. The use of such an approach can be potentially important and gives new information regarding NA proteins of influenza A virus.
EN
The aim of this study was to compare gait stability and variability between walking conditions and age groups. Methods: Twenty-six healthy younger and older females participated. Trunk acceleration in the vertical (V), medial-lateral (ML) and anteriorposterior (AP) directions during 5 minutes walking overground and 3 minutes walking on the treadmill at self-selected speed were recorded. Root mean square and standard deviations of acceleration, stride time and its variability, Lyapunov exponents (LE), multiscale entropy (MSE) and harmonic ratios (HR) were computed. Results: Both age groups showed significantly higher stride time variability and short-term LE in all directions during overground walking. For the older group, overground walking showed higher V and AP standard deviation. Significantly lower values for overground walking were observed for long-term LE (V and ML for the younger group, ML for the older group), HR (ML for the older group) and MSE (V for the older group). Significant age-related differences were found for V long-term LE for overground walking. Conclusions: The present findings suggest that both linear and advanced computational techniques for gait stability and variability assessment in older adults are sensitive to walking conditions.
15
Content available FMEA and its application in the SPC
EN
In today's industry, particularly in the automotive industry, the Failure Mode and Effects Analysis (FMEA) method is a frequently used tool. FMEA is one of the tools which help to identify the causes of process variability and thereby the possibilities of defect occurrence in the evaluated design including the evaluation of their relevant risks. This paper describes the application of the FMEA method to the manufacturing process, with the aim to identify the main causes of process variability, which can affect the resulting product. Further the article introduces other types of FMEA methods based on the basic model, however tailored for specific use in various areas. Finally, the measures, actions and recommendations for correct implementation of the FMEA process are mentioned.
PL
Obecnie w branży przemysłowej, szczególnie w przemyśle motoryzacyjnym, często stosuje się analizę rodzajów błędów oraz ich skutków (FMEA). FMEA jest jednym z narzędzi, które pomagają w identyfikacji przyczyn zmienności procesu, a tym samym możliwości wystąpienia usterki w ocenianym projekcie i ocenie jej istotnych zagrożeń. Niniejszy artykuł opisuje zastosowanie metody FMEA do analizy procesu produkcyjnego w celu zidentyfikowania głównych przyczyn zmienności tego procesu, które mogą wpływać na otrzymany wyrób. Jej celem jest określenie najlepszego podejścia, pozwalającego na osiągnięcie najbardziej pożądanych wyników. Ponadto w artykule przedstawiono inne typy metody FMEA, oparte na modelu podstawowym, które są dostosowane do konkretnego zastosowania w różnych dziedzinach. Omówiono środki, działania i zalecenia dotyczące prawidłowego wdrożenia procesu FMEA.
EN
The aim of this paper was the assessment of spatial and temporal complementarity of wind and solar resources based on selected locations in Poland. More specifically, we asked the following questions: a) does the spatial distribution of photovoltaic systems and wind farms own the property of smoothing the energy generation curve? b) is it possible as a result of renewable energy sources distribution over several locations to decrease instances of outliers in terms of energy production? c) to what extent depending on time step exists complementarity of sun and wind energy?. Conducted calculations were based on daily measurements of wind speed and insolation for the period 1984-2004 which were acquired from Institute of Meteorology and Water Management (IMGW) and www.soda-is.com. Obtained results are encouraging since the positive impact of spatial distribution on smoothing the energy generation curve was observed. From the power system point of view an expedient correlation between available wind and solar radiation in yearly time scale exists in analyzed locations.
PL
Celem przeprowadzonych badań było zbadanie czasowej oraz przestrzennej komplementarności energii promieniowania słonecznego oraz wiatru w wybranych lokalizacjach na terenie Polski. W pracy podjęto się odpowiedzi na następujące pytania: a) czy dystrybucja przestrzenna instalacji fotowoltaicznych oraz parków wiatrowych prowadzi do wygładzenia krzywej uzysku energii elektrycznej? b) czy jest możliwym by na skutek rozmieszczenia źródeł energii na kilka lokalizacji zminimalizować występowanie skrajnych wartości uzyskiwanego wolumenu energii c) w zależności od kroku czasowego, jak kształtuje się komplementarność zasobów wiatru oraz energii promieniowania słonecznego. Przeprowadzone analizy operały się na szeregach czasowych średniej dobowej prędkości wiatru oraz sumie nasłonecznienia, które obejmowały lata 1984-2004 i zostały pozyskane z Instytutu Meteorologii i Gospodarki Wodnej – Państwowy Instytut Badawczy oraz platformy www.soda-is.com. Uzyskane wyniki są zachęcające, ponieważ wykazano istnienie pozytywnego wpływu dystrybucji przestrzennej na wygładzenie krzywej uzysku energii. Co więcej zaobserwowano istnienie silnej ujemnej korelacji pomiędzy zasobami energii wiatru i promieniowania słonecznego w ujęciu rocznym.
17
Content available remote Distributed mesh generation for objects with shape variability
EN
The article presents an efficient way to generate a large number of finite element meshes to support statistical analysis of simulation of electromagnetic field inside biological objects which are characterized by a strong shape variability. Demonstrated solution uses capabilities of modern distributed computer systems and open source software. Parametric model of a hen egg has been used as a simple biological object to test the developed solution.
PL
Praca przedstawia efektywną metodę generowania wielu siatek elementów skończonych dla potrzeb modelowania pola elektromagnetycznego w obiektach o pochodzeniu biologicznym charakteryzujących się dużą zmiennością kształtu i ich statystycznej analizy. Do rozwiązania problemu zostały wykorzystane możliwości nowoczesnych systemów informatycznych o architekturze rozproszonej i otwartozródłowego oprogramowania. Do celów testów zaproponowanego rozwiązania został stworzony parametryczny model kurzego jaja jako przykład prostego obiektu biologicznego.
EN
Over the last 60 years, several models have been developed governing different zones of fatigue crack growth from the threshold zone to final failure. The best known model is the Paris law and a number of its based on mechanical, metallurgical and loading parameters governing the propagation of cracks. This paper presents an analytical model developed to predict the fatigue crack propagation rate in the Paris regime, for different material properties, yield strength (σy), Young’s modulus (E) and cyclic hardening parameters (K’, n’) and their influence by variability. The cyclic plastic deformation at a crack tip or any other cyclic hardening rule may be used to reach this objective, for to investigate this influence, these properties of the model are calibrated using available experimental data in the literature. This FCGR model was validated on Al-alloys specimens under constant amplitude load and shows good agreement with the experimental results.
EN
This paper introduces a mixed integer non-linear mathematical model for a simulation of a hybrid energy source consisting of photovoltaics (PV), wind turbines (WT) and pumped storage hydroelectricity (PSH). The concept of PV–WT–PSH has been well described and evaluated for sparsely populated or remote areas such as islands. Here, due to the rapid development of renewable energy sources and most importantly the variable (non-dispatchable) energy sources such as wind and solar, the idea of wind and solar powered PSHs has been investigated in the context of the national energy system. The economic and environmental impact of the proposed hybrid has been assessed. The results reveal that to cover almost 40% of the energy demand one should expect the energy cost to increase by 25%.
PL
Wypracowane od ponad 30 lat normy europejskie są umotywowane potrzebą rozwoju i dążeniem ich autorów do realizacji zamierzeń budowlanych o lepszej, wspólnej dla calej UE jakości (ekonomia, bezpieczeństwo, zrównoważony rozwój). Przyjęcie za podstawę w projektowaniu teorii niezawodności i przeniesienie jej metod do norm budowlanych daje nowe możliwości, ale jednocześnie stwarza też szereg zagrożeń i problemów, z którymi przychodzi się zmierzyć. Nowe pojęcia wykorzystywane w projektowaniu geotechnicznym, takie jak reliability base design, metoda obserwacyjna czy doświadczenie porównywalne wymagają zmiany w sposobie myślenia i szerszego otwarcia na nowe wymagania stawiane geotechnice i budownictwu w Polsce. Nowe idee to z pewnością większa rola i odpowiedzialność ekspercka projektanta geotechnicznego. Nowe idee w filozofii projektowania geotechnicznego to również zmiana "języka" (nowa klasyfikacja gruntów i skal), konieczność stosowania badań ilościowych (sondowania), dowolność w metodzie interpretacji oraz ostrożne oszacowanie parametrów w zależności od klasy zagrożeń wynikających z rangi obiektu i konsekwencji jego zniszczenia (ocena georyzyka). Celem artykułu jest przybliżenie nowych wymagań podanych w EC7 z uwagi na zapewnienia oczekiwanego poziomu niezawodności w odniesieniu do dotychczasowej praktyki projektowania geotechnicznego w budownictwie.
EN
The European Standards, developed over last 30 years, are driven by the need for evolution and their Authors' pursuit of better EU-wide quality in civil engineering, combining safety, economy, and sustainable development. The adoption of the theory of reliability as a basis for design, and its implementation in standards, provides new possibilities, as well as a number of risks at the same time, which the designer is faced with. New concepts used in geotechnical design, like the observational method, comparable experience, or reliability based design, require a change in thinking and wider opening to new requirements for geotechnical and civil engineering in Poland. These new concepts certainly emphasize the role and responsibility of geotechnical designers as experts in their field. Moreover, new ideas in the philosophy of geotechnical design are associated with new definitions (new classification of soils and rocks), the necessity of using quantitative tests, freedom of interpretation method choice, as well as cautious estimation of parameters, depending on the risk for the structure resulting from its importance and possible consequences of failure (georisk assessment). The paper presents new requirements in more humanistic terms, pointing to ideas underlining Eurocode 7 and its requirements, in relation to preexisting practice of geotechnical design in civil engineering.
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