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Search results for: ACTIVATED SLUDGE MODELS
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Application of muscle model to the musculoskeletal modeling
PublicationThe purpose of this paper is to investigate new fusiform muscle models. Each of these models treats a muscle as a system composedof parts characterized by different mechanical properties. These models explain the influence of differences in the stiffness of lateral parts and the degree of muscle model discretization. Each muscle model is described by a system of differential equations and a single integro-differential equation....
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Zero-Pole Approach in Microwave Passive Circuit Design
PublicationIn this thesis, optimization strategies for design of microwave passive structures including filters, couplers, antenna and impedance transformer and construction of various surroogate models utilized to fasten the design proces have been discussed. Direct and hybrid optimization methodologies including space mapping and multilevel algorithms combined with various surrogate models at different levels of fidelity have been utilized...
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Applying artificial neural networks for modelling ship speed and fuel consumption
PublicationThis paper deals with modelling ship speed and fuel consumption using artificial neural network (ANN) techniques. These tools allowed us to develop ANN models that can be used for predicting both the fuel consumption and the travel time to the destination for commanded outputs (the ship driveline shaft speed and the propeller pitch) selected by the ship operator. In these cases, due to variable environmental conditions, making...
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A new cold-active β-galactosidase from Arthrobacter sp. S3* - gene cloning, overexpression, purification and properties
PublicationA psychrotrophic bacterium producing a cold-active β-galactosidase was isolated from Spitsbergen soil and classified as Arthrobacter sp. S3*. The gene encoding β-galactosidase was isolated from the genomic DNA library, sequenced, cloned, expressed in Escherichia coli, purified by ion exchange chromatography and characterized. The Arthrobaster sp. S3* β-galactosidase is a homotrimeric enzyme composed of 74,4 kDa subunits. It is...
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2015. Motion analysis of a kitesurfer employing a vision-based measurement system
PublicationAbstract. Kitesurfing is a relatively new phenomenon with rising popularity worldwide – a recently developed extreme watersport considered a high-risk injury sport. It combines elements of several other sports, in particular, sailing, surfing, windsurfing, wakeboarding, and snowboarding. The main purpose of authors’ research in the present paper is to use a vision-based system for measuring a kitesurfer’s body movements in order...
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Zdolności dynamiczne do budowania chmury wartości w modelach biznesów
PublicationObserwacja współczesnych metod tworzenia wartości daje podstawy do wyłonienia nowej logiki ich generowania. Analiza modeli wytwarzania wartości przez przedsiębiorstwa np. sieciowe wykazała, że formułują one chmury wartości. Struktury tych chmur są różnorodne, niejednolite, kłębiaste. Przeprowadzone prace pozwoliły na sformułowanie obrazów wartości generowanych przez twarde komponenty modeli biznesów. Osiągnięcie tych wyników pozwoliło...
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Use of Data from Satellite Navigation System in Operational and Strategic Management of Transport in Cities
PublicationThe article presents the possibilities of using data from the Global Positioning System for the development of traffic models and examples of use this data in the transport management. Traffic models are useful tools in planning and evaluation of transport solutions, but also can be used for current, operational transport management.
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Applying Fuzzy Logic of Expert Knowledge for Accurate Predictive Algorithms of Customer Traffic Flows in Theme Parks
PublicationThis study analyzes two forecasting models based on the application of fuzzy logic and evaluates their effectiveness in predicting visitor expenditure and length of stay at a popular theme park. The forecasting models are based on a set of more than 600 decision rules constructed in the form of a complex series of IF-THEN statements. These algorithms store expert knowledge. A descriptive instrument that records the individual visitor's...
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Modelling fatalities on regional road networks
PublicationDuring the last decade Poland’s road fatalities went down by 44%. The trend differs from region to region. Effective road safetymanagement in regions requires tools for forecasting road safety measures and identifying factors influencing road fatality numbers. Mathematical models can provide such tools. They take into account local characteristics such as: demography, economy, infrastructure and motorization. Such models could...
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Multiscalar Model Based Control Systems for AC Machines
PublicationContents of the Chapter: Nonlinear transformations and feedback linearization. Models of the squirrel cage induction machine: Vector model of the squirrel cage induction machine. Multiscalar models of the squirrel cage induction machine.Feedback linearization of multiscalar models of the induction motor.Models of the double fed induction machine: Vector model of the double fed induction machine. Multiscalar model of the...
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Retention modeling of some saccharides separated on an amino column.
PublicationUsing an amino column (Supelcosil LC-NH2) and different mixtures of acetonitrile-water, quantitative structure-retention relationship models are discussed. These models are based on computed molecular descriptors representing numerically structured features of some saccharides. The obtained results are underlining the lipophilicity/hydrophilicity balance, and how this is controlling the separation of the saccharides. The resulting...
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Application of vertical flow constructed wetlands for highly contaminated wastewater treatment: preliminary results
PublicationBasing on quantitative and qualitative characteristics of reject waters (RWC) generated during dewatering of digested sewage sludge on centrifuges in conventional WWTP and municipal landfill leachate (LL), the pilot constructed wetlands for treatment of both types wastewater were designed and built. In the paper the conception, design and assumed treatment efficiencies of the pilot plants are presented. The water balance of the...
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Stability of roof trusses stiffened by trapezoidal sheeting and purlins
PublicationIn the article linear buckling analysis of a set of steel trusses braced by purlins and trapezoidal sheeting are conducted. The buckling load factor due to the height of a corrugated sheeting profile is investigated in parametric studies. The minimal height of trapezoidal sheeting required for preventing the sheeting and chords of the trusses against the buckling is obtained. Two groups of models are considered: “axial” model as...
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THE PHASE SHIFTERS INFLUENCE ON THE POWER SYSTEM STABILITY
PublicationThe paper presents the effect of phase shifters as FACTS devices on the possibility of improving the angle stability. Presented results obtained by the dynamic simulation performed on the mathematical model of the three machine system cooperating with the 400 kV network. The generative blocks models include turbine models with their controllers and models of synchronous generators with their excitation systems and voltage regulation....
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Pyrolysis Process of Whole Waste Tires as a Biomass Energy Recycling
PublicationThe article is devoted to the description of material recycling of whole waste tires, including a new method of pyrolysis process, resulting in the final products: technically oil fractions (rubber plasticizer of rubber compounds) or diesel fuels (light, medium and heavy), activated carbon, gas fuel and steel scrap. Operational and performance tests of the first version of the pilot plant, consisting of three contributions cooperating...
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3D Sound Intensity Measurement Around Organ Pipes Using Acoustic Vector Sensors
PublicationThe aim of the presented paper was to obtain and visualize sound intensity distribution of radiated acoustic energy around the organ pipes. The experimental setup consisted of the multichannel acoustic vector sensor and the specialized Cartesian robot. Measurements were performed in free field with spatial resolution of 0.1 [m]. Two organ pipes, i.e. wooden and metal were measured during the ex-periment. The organ pipes were activated...
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Optical Sensor Based Gestures Inference Using Recurrent Neural Network in Mobile Conditions
PublicationIn this paper the implementation of recurrent neural network models for hand gesture recognition on edge devices was performed. The models were trained with 27 hand gestures recorded with the use of a linear optical sensor consisting of 8 photodiodes and 4 LEDs. Different models, trained off-line, were tested in terms of different network topologies (different number of neurons and layers) and different effective sampling frequency...
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Determining and verifying the safety integrity level of the controland protection systems under uncertainty
PublicationThe probabilistic models of the electrical, electronic and programmable electronic (E/E/PE)systems, which are proposed in the IEC 61508 and IEC 61511 standards, do not cover the uncertainty aspectsof results obtained from these models. The proposed method takes into consideration the sensitivity analysisof probabilistic models of E/E/PE systems as well as the uncertainty of probabilistic results. It uses differentialfactors, which...
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Two examples of Quantum Dynamical Semigroups
PublicationThe Hamiltonians of the considered bi-partite systems are of the form $$ H_{S,R} = H_S /times 1_R + Q_{S} /times M_R + 1_S /times H_R $$ Subindex $S$ corresponds to the observed system and $R$ to the reservoir (the enviroment of $S$). Two classes of systems are distinguished: the discrete-continuous...
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A Multi-Fidelity Surrogate-Model-Assisted Evolutionary Algorithm for Computationally Expensive Optimization Problems
PublicationIntegrating data-driven surrogate models and simulation models of different accuracies (or fideli-ties) in a single algorithm to address computationally expensive global optimization problems has recently attracted considerable attention. However, handling discrepancies between simulation models with multiple fidelities in global optimization is a major challenge. To address it, the two major contributions of this paper include:...
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Surrogate Modeling and Optimization Using Shape-Preserving Response Prediction: A Review
PublicationComputer simulation models are ubiquitous in modern engineering design. In many cases, they are the only way to evaluate a given design with sufficient fidelity. Unfortunately, an added computa-tional expense is associated with higher fidelity models. Moreover, the systems being considered are often highly nonlinear and may feature a large number of designable parameters. Therefore, it may be impractical to solve the design problem...
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On Symmetry of Uniform and Preferential Attachment Graphs
PublicationMotivated by the problem of graph structure compression under realistic source models, we study the symmetry behavior of preferential and uniform attachment graphs. These are two dynamic models of network growth in which new nodes attach to a constant number m of existing ones according to some attachment scheme. We prove symmetry results for m=1 and 2 , and we conjecture that for m≥3 , both models yield asymmetry with high...
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Frequency and time domain characteristics of digital control of electric vehicle in-wheel drives
PublicationIn-wheel electric drives are promising as actuators in active safety systems of electric and hybrid vehicles. This new function requires dedicated control algorithms, making it essential to deliver models that reflect better the wheel-torque control dynamics of electric drives. The timing of digital control events, whose importance is stressed in current research, still lacks an analytical description allowing for modeling its...
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Decrease in Photovoltaic Module Efficiency Due to Deposition of Pollutants
PublicationThe deposition of pollutants on the surface of photovoltaic (PV) modules reduce the efficiency that can be achieved in given climatic conditions. This results in the loss of energy yield obtained from the solar installation. A number of factors determine the scale of this problem. The first of these is the amount of impurities deposited, the associated amount of precipitation, and the speed and direction of the wind. A second aspect...
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Strategies for Achieving Energy Neutrality in Biological Nutrient Removal Systems – a Case Study of the Slupsk WWTP (northern Poland)
PublicationThe paper presents a model-based evaluation of technological upgrades on the energy and cost balance in a large biological nutrient removal wastewater treatment plant (WWTP) in the city of Slupsk (northern Poland). The proposed upgrades include chemically enhanced primary sludge removal and reduction of the nitrogen load in the deammonification process employed for reject water treatment. Simulations enabled to estimate the increased...
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Strategies for achieving energy neutrality in biological nutrient removal systems - a case study of the Slupsk WWTP (northern Poland)
PublicationThe paper presents a model-based evaluation of technological upgrades on the energy and cost balance in a large biological nutrient removal wastewater treatment plant (WWTP) in the city of Slupsk (northern Poland). The proposed upgrades include chemically enhanced primary sludge removal and reduction of the nitrogen load in the deammonification process employed for reject water treatment. Simulations enabled to estimate the increased...
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Nonlinear strain gradient and micromorphic one-dimensional elastic continua: Comparison through strong ellipticity conditions
PublicationWe discuss the strong ellipticity (SE) conditions for strain gradient and micromorphic continua considering them as an enhancement of a simple nonlinearly elastic material called in the following primary material. Recently both models are widely used for description of material behavior of beam-lattice metamaterials which may possess various types of material instabilities. We analyze how a possible loss of SE results in the behavior...
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Doskonalenie logistycznego łańcucha dostaw w usługach w ujęciu relacyjnym
PublicationW literaturze zagadnienia związane z modelami doskonałości zarządzania łańcuchem dostaw, modelami zarządzania relacjami, modelami doskonałości EFQM oraz obszarami logistycznymi funkcjonują rozłącznie. Opracowany model w postaci MAPY RELACJI pozwala na pokazanie jak wyglądają korelacje między obszarami logistycznymi, obszarami działalności w odniesieniu do modeli doskonałości EFQM, modelami doskonałości zarządzania łańcuchem dostaw...
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Toward Robust Pedestrian Detection With Data Augmentation
PublicationIn this article, the problem of creating a safe pedestrian detection model that can operate in the real world is tackled. While recent advances have led to significantly improved detection accuracy on various benchmarks, existing deep learning models are vulnerable to invisible to the human eye changes in the input image which raises concerns about its safety. A popular and simple technique for improving robustness is using data...
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An Attempt to Create Speech Synthesis Model That Retains Lombard Effect Characteristics
PublicationThe speech with the Lombard effect has been extensively studied in the context of speech recognition or speech enhancement. However, few studies have investigated the Lombard effect in the context of speech synthesis. The aim of this paper is to create a mathematical model that allows for retaining the Lombard effect. These models could be used as a basis of a formant speech synthesizer. The proposed models are based on dividing...
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Fundamentals of Physics-Based Surrogate Modeling
PublicationChapter 1 was focused on data-driven (or approximation-based) modeling methods. The second major class of surrogates are physics-based models outlined in this chapter. Although they are not as popular, their importance is growing because of the challenges related to construction and handling of approximation surrogates for many real-world problems. The high cost of evaluating computational models, nonlinearity of system responses,...
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Model biznesu przedsiębiorstwa wodociągowego
PublicationW artykule przedstawiono badania nad wartościami modelu biznesu przedsiębiorstw wodociągowych w Polsce oraz przeprowadzono dyskusję nad ich postrzeganiem przez same przedsiębiorstwa. Wartości te w wielu aspektach postrzegane są w zbliżony sposób przez klientów. O ile jednak przedsiębiorstwa, jako istotne wartości postrzegały elementy związa-ne ze sprawnością i ciągłością procesu o tyle klienci kładli nacisk na sferę społeczną doty-czącą...
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Application of different building representation techniques in HEC-RAS 2-D for urban flood modeling using the Toce River experimental case
PublicationThis paper presents the impact of the choice of building representation techniques and hydrodynamic models on urban flood simulations using HEC-RAS 2-D for the Toce River physical model. To this end, eight numerical models based on previous laboratory experiments were prepared to simulate unsteady urban flooding on each side of building units. Two simplified building layouts (aligned and staggered) were examined, where models were...
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Modele budowy wartości dla klienta - charakterystyka i rozwinięcie
PublicationRozwój form realizacji biznesu umożliwił zbadanie nowych obiektów związanych z generowaniem wartości dla klienta i przedsiębiorstwa. W pracy scharakteryzowano logiki tworzenia wartości będące podstawą modeli łańcucha wartości, sklepu wartości, sieci wartości oraz chmury wartości. Zaproponowano także wprowadzenie nowego składnika do struktury tych modeli w postaci węzła wartości.
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An integrated framework for security protocol analysis
PublicationAssurance of security protocols needs particular attention. Flaws in a protocol can devastate security of the applications that rely on it. Analysis of the protocols is difficult and it is recommended that formal methods are employed to provide for higher levels of assurance. However, the formal methods can cover only a part of the scope of the problem. It is important that the formal models are valid representations of the protocol...
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Robustness Analysis of a Distributed MPC Control System of a Turbo-Generator Set of a Nuclear Plant – Disturbance Issues
PublicationTypically, there are two main control loops with PI controllers operating at each turbo-generator set. In this paper, a distributed model predictive controller with local quadratic model predictive controllers for the turbine generator is proposed instead of a set of classical PI controllers. The local quadratic predictive controllers utilize step-response models for the controlled system components. The parameters of these models...
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Numerical analysis and in situ tests of the Grot Rowecki Bridge in Warsaw
PublicationThe paper presents the FEM analysis of the reconstructed the Grot-Rowecki Bridge over Vistula river in Warsaw. The bridge has seven spans and consists of two independent structures with the longest spans of 120 m. After reconstruction the bridge is over 10 m wider. The numerical, nonlinear analysis has been con-ducted on a global and local FEM models. These models are defined so as they strictly comply with global structural bridge...
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Traffic Modeling in IMS-based NGN Networks
PublicationIn the modern world the need for accurate and quickly delivered information is becoming more and more essential. In order to fulfill these requirements, next generation telecommunication networks should be fast introduced and correctly dimensioned. For this reason proper traffic models must be identified, which is the subject of this paper. In the paper standardization of IMS (IP Multimedia Subsystem) concept and IMS-based NGN...
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Estimation of the steam condensation flow via CFD methods
PublicationThe results of numerical simulations to predict the performance of different steam models have been presented. All of the considered models of steam condensation have been validated on the base of benchmark experiment employing expansion in nozzle and next on the low pressure part of the steam turbine stage. For numerical analysis three models have been finally used – the ideal steam model without condensation, an equilibrium steam...
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The distributed model predictive controller for the nuclear power plant turbo-generator set
PublicationTypically there are two main control loops with PI controllers operating at each turbo-generator set. In this paper a distributed model predictive controller DMPC, with local QDMC controllers for the turbine generator, is proposed instead of a typical PI controllers. The local QDMC controllers utilize step-response models for the controlled system components. These models parameters are determined based on the proposed black-box...
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A Note on Reduced Strain Gradient Elasticity
PublicationWe discuss the particular class of strain-gradient elastic material models which we called the reduced or degenerated strain-gradient elasticity. For this class the strain energy density depends on functions which have different differential properties in different spatial directions. As an example of such media we consider the continual models of pantographic beam lattices and smectic and columnar liquid crystals.
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Modelling of Asphalt Mixes under Long Time Creep at Low Temperatures
PublicationProper description of asphalt mixtures behavior under long time load is one of the most important factors in analyses of strain and stress relations at low temperatures both from traffic and environmental loads. For example different models of thermal stress accumulation require different approaches of description of asphalt concrete. But in all cases it is required to describe its behavior under long time loading, which in some...
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How to model ROC curves - a credit scoring perspective
PublicationROC curves, which derive from signal detection theory, are widely used to assess binary classifiers in various domains. The AUROC (area under the ROC curve) ratio or its transformations (the Gini coefficient) belong to the most widely used synthetic measures of the separation power of classification models, such as medical diagnostic tests or credit scoring. Frequently a need arises to model an ROC curve. In the biostatistical...
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Numerical Analysis of Mice Carotid Arteries’ Response Emphasizing the Importance of Material Law Constants’ Validation
PublicationIn this paper, a detailed validation of the passive material properties of mice carotid arteries and constants of the Fung and Holzapfel hyperelastic material laws is conducted by means of static nonlinear FEM analyses. The response of the carotid arteries in an inflation test is studied here for the following mouse models: wild-type, mdx, sgcd−/−, Eln+/+, Eln+/−, Fbln5+/+, and Fbln5−/−. All FEM computations are conducted on models...
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On Reduced-Cost Design-Oriented Constrained Surrogate Modeling of Antenna Structures
PublicationDesign of contemporary antenna structures heavily relies on full-wave electromagnetic (EM) simulation models. Such models are essential to ensure reliability of evaluating antenna characteristics, yet, they are computationally expensive and therefore unsuitable for handling tasks that require multiple analyses, e.g., parametric optimization. The cost issue can be alleviated by using fast surrogate models. Conventional data-driven...
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Isothermal Calorimetry and Compressive Strength Tests of Mortar Specimens for Determination of Apparent Activation Energy
PublicationThe hydration process of cementitious materials involves a thermally activated reaction that depends on the composition of the mixture and the curing temperature. The main parameter affecting the temperature variation of cast-in-place concrete is the apparent activation energy, which can be used for the efficient prediction of the temperature evolution and maturity index of hardening concrete. This paper discusses two methods to...
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Degradation of bisphenol S – a contaminant of emerging concern - by synergistic ozone and percarbonate based AOP
PublicationDegradation of bisphenol S was studied using ozone activated by sodium percarbonate and the effectiveness of optimized process was compared with the peroxone process. The influence of several factors including sodium percarbonate concentration, ozone dose, pH, and water matrix were investigated. A synergetic coefficient of 3.84 was achieved for the combination of sodium percarbonate and ozone, confirming the effectiveness of this...
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Hypericum alpestre extract exhibits in vitro and in vivo anticancer properties by regulating the cellular antioxidant system and metabolic pathway of L‐arginine
PublicationConventional treatment methods are not effective enough to fight the rapid increase in cancer cases. The interest is increasing in the investigation of herbal sources for the development of new anticancer therapeutics. This study aims to investigate the antitumor capacity of Hypericum alpestre (H. alpestre) extract in vitro and in vivo, either alone or in combination with the inhibitors of the L‐arginine/polyamine/nitric oxide...
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Markov Model of Disease Development and Recovery
PublicationMarkov models are commonly used to simulate diseases and allow modeling of multiple health states and outcomes. Starting with the well known Le Bras multistate model (cascading failure model) with time-independent transitions we will see how simple Markov mortality models may be pressed into the service of survival and event history analysis. We will focus on more complex models which will be able to take into account remission,...
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FEM approach to modeling of an irregular trabecular structure
PublicationThe aim of the study is elaboration of a method for creating irregular scaffolds that can be used to model the behaviour of trabecular bone placed in the proximal epiphysis of the femur. The scope of the study encompasses creating six numerical models of irregular scaffolds (two solid irregular scaffolds, two shell irregular scaffolds and two shell irregular scaffolds with fortification) and performing numerical analysis of the...