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Search results for: normally consolidated soils
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Electro-chemo-mechanical properties in nanostructured Ca-doped ceria (CDC) by field assisted sintering
PublicationRecent investigations have shown that highly oxygen defective cerium oxides generate non-classical electrostriction that is superior to lead-based ferroelectrics. In this work, we report the effect of field-assisted spark plasma sintering (SPS) on electro-chemo-mechanical properties of calcium doped ceria (CDC). Nanometric powders of Ca.10 nm are rapidly consolidated to form polycrystalline nanostructures with a high degree of...
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Electrical conductivity of nanostructured acceptor-doped ceria fabricated by spark plasma sintering (SPS)
PublicationHigh purity nanoscale powders (~10–15 nm size) of two different compositions of ceria, doped with Gd3+ and Ca2+, have been consolidated by spark plasma sintering (SPS) at different temperatures. Fully-dense samples were observed only at a sintering temperature of 980 °C. The as-sintered samples showed rather fast grain growth with an average grain size below 300 nm. The electrical properties of the samples were evaluated by impedance...
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Phytoremediation of heavy metals by white cabbage
PublicationPhytoremediation is regarded as the cheapest and environmentally most friendly technology for cleaning up soil. The most widespread and most profitable technique is phytoextraction, used mainly for removing heavy metals and radioactive elements from thesoil. Over 400 plant species have been identified as natural metal hyperaccumulators representing about 0.2 % of all angiosperms. Unfortunately, most of these plants are characterised...
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Fashion and Tourism: Parallel Stories of Two "Dream Marvels".
PublicationFashion and tourism are two social, cultural, and economic phenomena that have both numerous connections and surprising similarities. These are not new: they have been built and developed since the beginnings of tourism as a modern social phenomenon, emerged in Europe in the context of the industrial revolution. They consolidated in the first decades of the 21st century, in a context where both phenomena have completed their “mass”...
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Influence of Soft Soil Samples Quality on the Compressibility and Undrained Shear Strength – Seven Lessons Learned From the Vistula Marshlands
PublicationThis technical article presents the influence of sample quality on the compressibility parameters and undrained shear strength ( c u ) of soft soils from the Vistula Marshlands. The analysis covers: (1) quality of soft soil according to three criteria: void ratio (Δ e / e 0 index), volumetric strain (Δ ɛ v ) and C r / C c ratio; (2) influence of storage time on quality; (3) influence of sample quality on undrained shear strength...
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Public Finance in Poland in a COVID Fog: A Look Through the Lens of Fiscal Transparency and Accountability
PublicationAbstract. Goal– The aim of the article is to identify dysfunctional phenomena (implementation of specific mechanisms/solutions and actions taken), generating increased opacity and limit the responsibility/accountability of public f inance in Poland, exacerbated by the COVID-19 crisis. Methods– descriptive analysis, comparative analysis and financial analysis methods were used. Results– fiscal transparency and accountability in...
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Influence of soil anisotropic stiffness on the deformation induced by an open pit excavation.
PublicationIn this paper, the problem of deformation induced by an open pit excavation in anisotropic stiff soils is analysed by FE modelling. The presented research is focused on the influence of material model with anisotropic stiffness on the accuracy of deformation predictions as compared with the field measurements. A new hyperelastic-plastic model is applied to simulate anisotropic mechanical behaviour of stiff soils. It is capable...
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Improvement of subsoil and railway substructure by explosive means.
PublicationQuick and effective method of subsoil and railway substructure improvement by using explosive means (registered trade name: microblasting) allowes design and construct railways on lowered bearing soils (i.e. wetlands, marshlands, industrial by-products, municipal wastes, degraded antropogenic embankments). It is usefull and recommendable technology to construct new railways, modernization or maintenance and repairing of old ones...
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Soil and groundwater fecal contamination as a result of sewage sludge land application.
PublicationThe release of sludge-born bacteria and their further transport in subsurface was studied. The migration of bacteria was investigated in column experiments which were carried out under the conditions corresponding to naturally occurring extreme rainfall. Coal fly ash as well as coarse and medium grained sand, which properties are similar to the soils present in degraded areas, were used as column beds. Sewage sludge was applied...
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SIGNIFICANT GUIDELINE FOR THE DAMAGE INDICES APPLIED TO REINFORCED CONCRETE STRUCTURES
PublicationIn this paper, based on a deep overview and literature study, the different formulas proposed for damage indices (DIs) applied to reinforced concrete structures under monotonic or cyclic loading are classified and presented. The DIs are applied to quantify the damages to structures, ranging from zero to one. Normally, they are applied to make a decision for repairing or demolition of the structures in the post-earthquake phases. Keywords:...
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ANALYSIS OF THE PUNCHING FAILURE MECHANISM IN WORKING PLATFORMS
PublicationPaper presents an analysis of the shear failure mechanism which occurs from the punching of a working platform layer in relation to its thickness, grain size arrangement and mechanical properties, taking into consideration the interaction with soft subgrade. The study is based on the observations of performance of natural scale structures (Streefkerk) and the results of model investigations numerically represented with the use...
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Direct design of Controlled Modulus Columns (CMC) based on in-situ testing
PublicationIn this paper, the serviceability limit state and bearing capacity of tension screw displacement piles were analyzed using the results of static pile load tests, carried out on the test plot near the Elbląg city, and field, and laboratory tests. The paper presents the methodology of determining the pile load-settlement curve using different types of t-z transfer functions. The new method of constructing the pile load-settlement...
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Modelling the context of use for Intranet portals design
PublicationIntranet portals in contemporary enterprises affect the way how people work, communicate and build relationships within teams and organizations. Developing high usability in Intranet projects requires analysing context of use and including many additional organizational and cultural factors, normally not present in regular software projects. A modelling framework presented in this paper is useful for analysing context of use for...
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Effects of Xanthan Gum Biopolymer on the Permeability, Odometer, Unconfined Compressive and Triaxial Shear Behavior of a Sand
PublicationBiopolymers, which are microbially induced polymers, can be used as an alternative material to improve engineering performance of soils. In this paper, a laboratory study of 0.075-1.0 mm size sand and biopolymer (i.e., xanthan gum) mixtures with various mix ratios (0%, 0.5%, 1.0%, and 1.5%) was performed. The materials, specimen preparation, and test methods are described, as are the results of a suite of permeability, odometer, unconfined...
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Mechanical Properties of a Dike Formed from a Soil-ash Composite
PublicationThe paper presents the research results on application of composite soils for dike construction. The composite soil is produced by mixing bottom ash (by-product of energetics) with dredged material (sand) taken from the mouth of The Vistula river. The optimum composite for dike core was chosen with respect to mechanical parameters: high internal friction angle, good compaction and reduced hydraulic conductivity. The test dike was...
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Bearing capacity of the working platform with kinematic method
PublicationBearing capacity of the working platform for heavy tracks was analysed using Distinct Layout Optimization (DLO) method. The platform layer constructed from cohesionless soils is resting on weak cohesive subgrade. Different thickness of the platform, its effective angle of internal friction and undrained shear strength of the soft soil were taken into consideration. Kinematic method permits different failure mechanisms to be analyzed....
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The innovative exploitation of Brassica vegetables in the production of quality food for health. From lab bench to field and fork.
PublicationThe specific chemical composition of vegetables belonging to Brassicaceace , as regard both nutrients and non-nutrients, renders them particularly suitable for the health food production chain. The ability of these plants to accumulate heavy metals may be utilised for phytoremediation of arable soils, but also as a vehicle to fortify foods in micronutriens such as selenium. The bioactive organosulfur compounds, especially glucosinolates...
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Determination of p-y curves for offshore piles based on in-situ soil investigations
PublicationOffshore piles are subjected to complex loads with considerable lateral component. The pile-soil response to lateral loads can be described with the p-y method. For a given depth the load–deflection relationship is built to simulate the surrounding soil stiffness. This state-of-art paper presents a brief discussion of determination methods for the p-y curves using a standard approach based on the soil parameters derived from laboratory...
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Detekcja i lokalizacja nieprzewodzenia tranzystorów falownika napięcia na podstawie analizy prądu obciążenia
PublicationPrzedstawiono nową metodę detekcji i lokalizacji nieprzewodzenia tranzystorów w falownikach napięcia zasilających silniki indukcyjne małej mocy. Metoda bazuje na monitorowaniu wartości dwóch sygnałów dia-gnostycznych. Pierwszy z nich, wskaźnik braku przepływu prądu, wykorzystano w celu detekcji uszkodzeń. Drugi, stosunek wartości średniej prądu do wartości średniej bezwzględnej, zawiera informacje umożliwiające lokalizację uszkodzonych...
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Open-transistor fault diagnostics in voltage-source inverters by analyzing the load current
PublicationA novel method is presented for the detection andisolation of open-transistor faults in voltage-source invertersfeeding low-power AC motors. The method is based onmonitoring two diagnostic signals, one indicating sustained nearzerovalues of output current and thus permitting fault detection,the other permitting the isolation of the particular transistorwhich went faulty. The latter signal is the ratio of the averagephase current...
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Use of Brassica plants in the phytoremediation and biofumigation processes
PublicationIn recent decades, serious contamination of soils by heavy metals has been reported. It is therefore a matter of urgency to develop a new and efficient technology for removing contaminants from soil. Another aspect to this problem is that environmental pollution decreases the biological quality of soil, which is why pesticides and fertilizers are being used in ever-larger quantities. The environmentally friendly solutions to these...
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Genetic and biochemical characterization of yeasts isolated from Antarctic soil samples
PublicationThe Polish Arctowski Station is situated in the maritime Antarctic on the western shore ot' Admiralty Bay and encompasses terrestrial habitats which are not perma-nently covered by ice, in contrast to morę than 90% of the island's surface area. Over the past several decades, stud-ies exploring the soils of those habitats have revealed a considerable diversity of bacteria, filamentous fungi, and, to a lesser extent, yeasts; however,...
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Validating the Rules of Government Automation
PublicationThere is growing evidence on the benefits and risks of government automation, and how should government organizations proceed with automation when the benefits outweigh the risks. This evidence was recently consolidated into the "rules of government automation", part of the project funded by the Inter-American Development Bank. The project uncovered that the combined nature of government work and its transformation into digital...
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Module architecture as alternative approach to traditional construction processes
PublicationModule architecture today is a special type of building construction process that combines repetitive design, low-cost production based on prefabricated elements and fast erection. Module does not mean the same as modular. In general, module architecture today refers to the design of any system composed of separate components, manufactured before in factory, that can be connected together at the building site much faster than normally....
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Remote Sensing Methods In the Study of the Impact of Long-Term Process of Sulphur Mining on Environmental Changes of the Carpathian Foreland
PublicationThe paper presents research on the extent of impact of sulphur mining process and post-mining activities upon properties of selected elements of the environment, as well as the assessment of the influence of indirect effects resulting from many years' process of exploitation of sulphur deposits in the areas of the Carpathian Foreland (south-east Poland). Within the scope of research conducted, the assessment of the extent of...
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Geotechnical characterization of soft soil deposits in Northern Poland
PublicationThis paper presents a geotechnical characterization of deltaic soft soil deposits in the Vistula Marshlands, northern Poland. It shows the limited applicability of organic soil classifications based on Cone Penetration Tests (CPTU) and Dilatometer Tests (DMT). None of the in-situ-based classifications correctly identifies peat. Analysis of the behaviour of contractive/dilative soil layers according to Robertson's updated classification...
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Układy sterowania bramkowego tranzystorów z węglika krzemu SiC JFET w falownikach napięcia
PublicationZastosowanie technologii węglika krzemu (SiC) w falownikach napięcia pozwala na zwiększenie częstotliwości przełączeń oraz temperatury pracy przyrządów półprzewodnikowych. W celu zapewnienia minimalizacji strat oraz określonych właściwości dynamicznych tranzystorów z węglika krzemu wymagane jest stosowanie zaawansowanych układów sterowania bramkowego. W referacie przedstawiono analizę teoretyczną, wyniki badań symulacyjnych oraz...
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Status and trends of mercury pollution of the atmosphere and terrestrial ecosystems in Poland
PublicationThe goal of this paper is to assess the current status and trends of total mercury (THg) contamination of the atmosphere and terrestrial ecosystems in Poland. The study shows that the reduced domestic and worldwide atmospheric emission of Hg resulted in decreased THg level in the terrestrial biotope and biosphere. Considering that Poland is one of the main Hg emitters in Europe, the THg concentrations in its abiotic environment...
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Oil removal from polluted soil by washing with surfactants solutions in dynamic conditions
PublicationFor washing of the oil from polluted soil surfactants solutions were applied. In a research a nonionic synthetic surfactant - polyoxyethylene ether of synthetic fatty alcohol (Rokanol NL6), rhamnolipid biosurfactant JBR 425 (Jeneil Biosurfactant Co. LLC) and their mixtures were used. Results of oil removal from peat soil and sand with mixtures of surfactants solutions at concentration 0,5 g/dm...
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Automatic Correction of Non-Anechoic Antenna Measurements using Low-Pass Filters
PublicationPrototype measurements belong to key steps in the development of antenna structures. They are normally performed in expensive facilities, such as anechoic chambers (ACs). Alternatively, antenna performance can be extracted (at a low cost) in non-anechoic conditions upon appropriate post-processing. Unfortunately, existing correction algorithms are difficult to set up and prone to failure, which limits their practical usefulness....
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Cost-Efficient EM-Driven Size Reduction of Antenna Structures by Multi-Fidelity Simulation Models
PublicationDesign of antenna systems for emerging application areas such as the Internet of Things (IoT), fifth generation wireless communications (5G), or remote sensing, is a challenging endeavor. In addition to meeting stringent performance specifications concerning electrical and field properties, the structure has to maintain small physical dimensions. The latter normally requires searching for trade-off solutions because miniaturization...
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Isotope-labeled substances in analysis of persistent organicpollutants in environmental samples
PublicationUltratrace analysis of persistent organic pollutants (POPs) in environmental samples requires very sophisticated methods for both sample preparation and instrumental analysis. The complex matrix requires a multi-stage procedure. Each stage is a potential source of error, as a consequence of which the final result of analysis could be a source of misinformation rather than information. The individual stages and the procedure as...
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White cabbage in the biofumigation process- expectations and perspectives
PublicationHealth risks related to common use of pesticides and artificial fertilizers raised the interest in alteranative methods of crop protection, among them biofumigation is becoming the most promising. In this process certain natural compounds, mainly degradation products of glucosinolates produced by Brassica species are used to combat pests and microorganisms attacking crops. Increased synthesis of these bioactive compounds can be...
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Seismic pounding between adjacent buildings: Identification of parameters, soil interaction issues and mitigation measures
PublicationStructural pounding has been observed in many previous earthquakes due to insufficient gap commonly provided between adjacent structures. The collisions usually generate large impact forces and short duration acceleration pulses which may result in significant damage to the colliding buildings. Because of that, earthquake induced structural pounding has been intensively studied and investigated for the last three decades. Results...
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Accurate Post-processing of Spatially-Separated Antenna Measurements Realized in Non-Anechoic Environments
PublicationAntenna far-field performance is normally evaluated in expensive laboratories that maintain strict control over the propagation environment. Alternatively, the responses can be measured in non-anechoic conditions and then refined to extract the information on the structure field-related behavior. Here, a framework for correction of antenna measurements performed in non-anechoic test site has been proposed. The method involves automatic...
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Acceptance Testing of Software Products for Cloud-Based On-Line Delivery
PublicationSoftware products intended for on-line delivery by distributors serving an open community of subscribers are developed in a specific life-cycle model, in which roles of the major stakeholders are strongly separated, unlike in any other software development model known in software engineering. Its specificity underlines the fact that a distributor of the final product, responsible for its acceptance for publication and delivery...
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Training Services in Small and Medium-sized Enterprises: Evidence from Poland
PublicationIn the knowledge-based economy knowledge and skills are becoming more and more significant for the success of companies. This applies also to firms from small and medium-sized enterprises (SMEs) sector. As large companies in many cases posses special divisions devoted to trainings, they normally have no problems with updating the knowledge and skills of their employees. The situation is different with regard to SMEs, which often...
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Advances in CSI-fed induction motor drives
PublicationThe application of current source inverters (CSI)in induction motor (IM) drives offers a number of advantages,including: voltage boosting capability, natural shoot-throughshort-circuit protection and generation of sinusoidal voltages.The exact generation of sinusoidal voltages is possible thanks tothanks to the effect of the output ac filter capacitors and mayimprove the accuracy of sensorless IM control. The eliminationof high...
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Shape Memory Materials from Rubbers
PublicationSmart materials are much discussed in the current research scenario. The shape memory effect is one of the most fascinating occurrences in smart materials, both in terms of the phenomenon and its applications. Many metal alloys and polymers exhibit the shape memory effect (SME). Shape memory properties of elastomers, such as rubbers, polyurethanes, and other elastomers, are discussed in depth in this paper. The theory, factors...
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Low-frequency noise in ZrS3 van der Waals semiconductor nanoribbons
PublicationWe report the results of the investigation of low-frequency electronic noise in ZrS3 van der Waals semiconductor nanoribbons. The test structures were of the back-gated field-effect-transistor type with a normally off n-channel and an on-to-off ratio of up to four orders of magnitude. The current–voltage transfer characteristics revealed significant hysteresis owing to the presence of deep levels. The noise in ZrS3 nanoribbons...
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The innovative Exploitation of Brassica Vegetables in the Health Quality Food Production Chain
PublicationIn this overview the multidirectional opportunities of innovative exploitation of chemical and biological properties of vegetables from Brassiceae family are discussed. The specific chemical composition of brassicas, as regard both nutrients and non-nutrients, renders them particularly suitable for the health food production chain, literally from field to fork. the ability of these plants to accumulate heavy metals may be utilised...
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The innovative exploitation of Brassica vegetables in the health quality food production chain
PublicationIn this overview the multidirectional opportunities of innovative exploitation of chemical and biological properties of vegetables from Brassiceae family are discussed. The specific chemical composition of brassicas, as regard both nutrients and non-nutrients, renders them particularly suitable for the health food production chain, literally from field to fork. the ability of these plants to accumulate heavy metals may be utilised...
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Application of Feed Forward Neural Networks for Modeling of Heat Transfer Coefficient During Flow Condensation for Low and High Values of Saturation Temperatur
PublicationMost of the literature models for condensation heat transfer prediction are based on specific experimental parameters and are not general in nature for applications to fluids and non-experimental thermodynamic conditions. Nearly all correlations are created to predict data in normal HVAC conditions below 40°C. High temperature heat pumps operate at much higher parameters. This paper aims to create a general model for the calculation...
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Light4Health eLearning Course: health research for interior lighting design. Re-thinking design approaches based on science
PublicationThis paper presents the results of 'Light4Health' (L4H), a three-year EU Erasmus+ Strategic Partnership grant project (2019-2021), which investigated, systematized and taught health-related research on the impact of natural and artificial light on human health and well-being relevant to indoor lighting design. The objective was to re-think evidence-based lighting design approaches for residential, working/educational, and healthcare...
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TR-Based Antenna Design with Forward FD: The Effects of Step Size on the Optimization Performance
PublicationNumerical methods are important tools for design of modern antennas. Trust-region (TR) methods coupled with data-efficient surrogates based on finite differentiation (FD) represent a popular class of antenna design algorithms. However, TR performance is subject to FD setup, which is normally determined a priori based on rules-of-thumb. In this work, the effect of FD perturbations on the performance of TR-based design is evaluated...
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The point estimate method in a reticulated shell reliability analysis
PublicationThe objective of this paper is to present an application of the point estimate method (PEM) that can determine the probabilistic moments for engineering structures. The method is reasonably robust and adequately accurate for a wide range of practical problems. It is a special case of numerical quadrature based on orthogonal polynomials. The main advantage of this method is that, unlike FORM or SORM, it is not necessary to carry...
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Application of Bayesian Networks in risk diagnostics arising from the degree of urban regeneration area degradation
PublicationUrban regeneration as a complex project, generates many extremely specific threats affecting the increase of investment risk. Its unique nature causes that probability parameter, normally applied in the process of risk quantification, is extremely difficult to estimate. Due to lack of historical data urban regeneration related activities are therefore associated with uncertainty. According to the authors, a useful tool for resolving...
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Application of BN in Risk Diagnostics Arising from the Degree of Urban Regeneration Area Degradation
PublicationUrban regeneration as a complex project, generates many extremely specific threats affecting the increase of investment risk. Its unique nature causes that probability parameter, normally applied in the process of risk quantification, is extremely difficult to estimate. Due to lack of historical data urban regeneration related activities are therefore associated with uncertainty. According to the authors, a useful tool for resolving...
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Modelling of the Heat Flux Density Distribution for Laser Beam Welding
PublicationGreat interest of the laser beam welding in industry is a new theoretical task, making planning the welding procedure specification and the quality control of welded joints easier. Estimating and calculating the dimensions of a weld pool and temperature distribution near weld mainly concern heat source modelling. In the presented work calculations of welding pool shape and thermal field for cylindrical-powered-normally model of...
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Ultimate strength of stiffened plates subjected to compressive load and spatially distributed mechanical properties
PublicationThe present study deals with the ultimate strength of stiffened plates subjected to spatially distributed mechanical properties and compressive load. Normally, mean values of mechanical properties based on tensile tests are used to validate the numerical assessment with experimental results. However, mechanical properties may vary within a single specimen. To investigate the impact of that, random fields of yield stress and Young...