Search results for: double inverted pendulum

A comprehensive approach to double inverted pendulum modelling
PublicationThe problem of mathematical modelling and indication of properties of a DIP has been investigated in this paper. The aim of this work is to aggregate the knowledge on a DIP modelling using the EulerLagrange formalism in the presence of external forces and friction. To indicate the main properties important for simulation, model parameters identification and control system synthesis, analytical and numerical tools have been used....

An Automatic SelfTuning Control System Design for an Inverted Pendulum
PublicationA control problem of an inverted pendulum in the presence of parametric uncertainty has been investigated in this paper. In particular, synthesis and implementation of an automatic selftuning regulator for a real inverted pendulum have been given. The main cores of the control system are a swingup control method and a stabilisation regulator. The first one is based on the energy of an inverted pendulum, whereas the second one...

Metody strojenia regulatorów typu PID z wykorzystaniem technologii syntezy regulatorów od stanu
PublicationUkłady sterujące typu PID są jednymi z najbardziej popularnych regulatorów wykorzystywanych w układach regulacji. W związku z tym znanych jest szereg metod doboru wartości ich parametrów (nastaw). Obok różnych metod inżynierskich czy analitycznych strojenia tego typu regulatorów, dostępne są również podejścia bazujące na optymalizacji. Wskaźnikiem jakości znajdującym w nich zastosowanie jest np. całka z kwadratu uchybu. W artykule...

Cooperation of mono and biarticular muscles: human lower limb
PublicationObjectives: The aim of this study was to create and analyze a Paretooptimal problem that would describe cooperation between mono and biarticulate lower limb muscles in sagittal plane. Methods: Equations describing the problem were derived and analyzed, additional constrains were introduced and experimental verification based on gait video analysis was performed. Results: Uncertainty of Paretooptimal solution is shown for the...

Porous structures in aspects of transpirating cooling of oxycombustion chamber walls
PublicationA wet oxycombustion chamber, which must be effectively cooled due to high temperature evolved during the oxycombustion process, by using the phenomena of Reynolds thermal transpiration and Navier slip velocity. Closures needed to execute mass flow rate in a microchannel, which should be treated as a single porous structure in the walls of the combustion chamber, have been obtained by applying a local 3D approach. The NavierStokes...

The 41Σ+ electronic state of LiCs molecule
PublicationThe 41Σ+ state of LiCs molecule is observed experimentally for the first time. The inverted perturbation approach (IPA) method is used to derive the potential energy curve of the state from the measured spectra. The experiment is accompanied by theoretical calculations of adiabatic potentials for excited states in LiCs including 41Σ+, performed with the MOLPRO program package. The irregular shape of the 41Σ+ state potential predicted...

Experimental Study on Effectiveness of a Prototype Seismic Isolation System Made of Polymeric Bearings
PublicationSeismic isolation is identified as one of the most popular and effective methods of protecting structures under strong dynamic excitations. Base isolators, such as Lead Rubber Bearings, High Damping Rubber Bearings, and Friction Pendulum Bearings, are widely used in practice in many earthquakeprone regions of the world to mitigate structural vibrations, and therefore minimize loss of life and property damage during seismic events....

Dynamic Bankruptcy Prediction Models for European Enterprises
PublicationThis manuscript is devoted to the issue of forecasting corporate bankruptcy. Determining a firm’s bankruptcy risk is one of the most interesting topics for investors and decisionmakers. The aim of the paper is to develop and to evaluate dynamic bankruptcy prediction models for European enterprises. To conduct this objective, four forecasting models are developed with the use of four different methods—fuzzy sets, recurrent and...

Modelling of planar movement dynamics of upper limb
PublicationThe original model describing planar movement dynamics of upper limb is presented. The upper limb is modelled as twojoints system loaded by external forces and internal forces of striated skeletal muscles. A behaviour of each muscle is modelled as a system composed of serially linked rheologic fragments that have different mechanical properties. These muscle models allow us to simulate a behaviour of short fusiform muscle (3DOF...

Thermal and Chemical Expansion in Proton Ceramic Electrolytes and Compatible Electrodes
PublicationThis review paper focuses on the phenomenon of thermochemical expansion of two specific categories of conducting ceramics: Proton Conducting Ceramics (PCC) and Mixed IonicElectronic Conductors (MIEC). The theory of thermal expansion of ceramics is underlined from microscopic to macroscopic points of view while the chemical expansion is explained based on crystallography and defect chemistry. Modelling methods are used to predict...

The adiabatic potentials of lowlying electronic states of the NaRb molecule
PublicationAdiabatic potential energy curves and spectroscopic constants have been calculated for the NaRb molecule. The results of ten states of the symmetry Σ+, six states of the symmetry Π, and two states of the symmetry Δ are obtained by the nonrelativistic quantum chemical method used with pseudopotentials describing the interaction of valence electrons with atomic cores. Analysis is based on a comparison with the results of other theoretical...

Reducedcost design closure of antennas by means of gradient search with restricted sensitivity update
PublicationDesign closure, i.e., adjustment of geometry parameters to boost the performance, is a challenging stage of antenna design process. Given complexity of contemporary structures, reliable parameter tuning requires numerical optimization and can be executed using local algorithms. Yet, EMdriven optimization is a computationally expensive endeavour and reducing its cost is highly desirable. In this paper, a modification of the trustregion...

Calculation of adiabatic potentials of Li2
PublicationInformujemy o adiabatycznych krzywych energii potencjalnej cząsteczki litu. Nasze krzywe są stabelowane według odległości międzyatomowej od 3,2 a0 do 88a0. Porównujemy nasze wyniki teoretyczne z wynikami obliczonymi przez innych autorów oraz krzywymi energii potencjalnej wyprowadzonymi z eksperymentów. W naszym podejściu używamy metody konfiguracji wzajemnego oddziaływania, gdzie tylko elektrony walencyjne atomu Li są traktowane...

Projekt systemu sterowania dwukołowym robotem balansującym
PublicationW niniejszym artykule rozważony został problem sterowania dwukołowym robotem balansującym. Celem zaprezentowanych prac było zaprojektowanie systemu sterowania tego typu obiektem z wykorzystaniem metod nowoczesnej teorii sterowania. W ramach syntezy, bazując na wyprowadzonym w oparciu o zasady dynamiki Newtona modelu, dobrana została struktura systemu sterowania w postaci regulatora wykorzystującego sprzężenie zwrotne od stanu oraz...

Design of Jackup Platform for 6 MW Wind Turbine: Parametric Analysis Based Dimensioning of Platform Legs
PublicationThe article presents the results of the research conducted within the framework of the project entitled WINDTUPLA (ERANET, MARTEC II), the general aim of which was to design and analyse supporting structures for wind turbines intended for operation on the South Baltic area. The research part described in the article aimed at developing a preliminary design for a jackup platform which can operate on water areas with depth of...

Expedited EMDriven Design of Miniaturized Microwave Hybrid Couplers Using SurrogateBased Optimization
PublicationMiniaturization of microwave hybrid couplers is important for contemporary wireless communication engineering. Using standard computeraided design methods for development of compact structures is extremely challenging due to a general lack of computationally efficient and accurate simulation models. Poor accuracy of available equivalent circuits results from neglecting parasitic crosscouplings that greatly affect the performance...

Fabrication and Characterization of Flexible MedicalGrade TPU Filament for Fused Deposition Modeling 3DP Technology
PublicationThe possibility of using additive manufacturing (AM) in the medicine area has created new opportunities in health care. This has contributed to a sharp increase in demand for 3D printers, their systems and materials that are adapted to strict medical requirements. We described herein a medicalgrade thermoplastic polyurethane (STPU) which was developed and then formed into a filament for Fused Deposition Modeling (FDM) 3D printers...

Preferencebased evolutionary multiobjective optimization in ship weather routing
PublicationIn evolutionary multiobjective optimization (EMO) the aim is to find a set of Paretooptimal solutions. Such approach may be applied to multiple reallife problems, including weather routing (WR) of ships. The route should be optimal in terms of passage time, fuel consumption and safety of crew and cargo while taking into account dynamically changing weather conditions. Additionally it must not violate any navigational constraints...

Foucault's pendulum. Uncomplicated tool in the study of geodesy and cartography
PublicationModern education methods often refer to the sophisticated and technologically advanced methods. In the process of education the latest technologies and inventions should be presented. Modern research achievements becomes an indispensable part of the technical studies. However the learning process of an engineer should refer to the standard methods of measurement and well known fundamental instruments. One of the simplest devices...

Infiltration in a doubleporosity medium: Experiments and comparison with a theoretical model
PublicationThis paper presents experimental verification of the mathematical model of unsaturated flow in double‐porosity soils developed by the asymptotic homogenization method. A series of one‐dimensional infiltration experiments was carried out in a column filled with a double‐porosity medium composed of a mixture of sand and sintered clayey spheres arranged in a periodic manner. The unsaturated hydraulic properties of each porous material...

On the double bondage in graphs
PublicationA vertex of a graph is said to dominate itself and all of its neighbors. A double dominating set of a graph G=(V,E) is a set D of vertices of G such that every vertex of G is dominated by at least two vertices of D. The double domination number of a graph G, denoted by gamma_d(G), is the minimum cardinality of a double dominating set of G. The double bondage number of G, denoted by b_d(G), is the minimum cardinality among all sets...

Minimal double dominating sets in trees
PublicationWe provide an algorithm for listing all minimal double dominating sets of a tree of order $n$ in time $\mathcal{O}(1.3248^n)$. This implies that every tree has at most $1.3248^n$ minimal double dominating sets. We also show that this bound is tight.

Fake VIP Attacks and Their Mitigation via DoubleBlind Reputation
PublicationIn a generic setting subsuming communication networks, resource sharing systems, and multiagent communities, a client generates objects of various classes carrying classdependent signatures, to which a server assigns classdependent service quality. A Fake VIP attack consists in false declaration of a high class, with an awareness that detection of object signature at the server side is costly and so invoked reluctantly. We show...

A low complexity doubletalk detector based on the signal envelope
PublicationA new algorithm for doubletalk detection, intended for use in the acoustic echo canceller for voice communication applications, is proposed. The communication system developed by the authors required the use of a doubletalk detection algorithm with low complexity and good accuracy. The authors propose an approach to doubletalk detection based on the signal envelopes. For each of three signals: the farend speech, the microphone...

A doubletalk detector using audio watermarking
Publicationa novel approach to doubletalk detection in the acoustic echo canceler is proposed. a hidden signature is embedded into the arriving signal, using the echohiding method. next detection of the presence of this signature in the microphone signal is performed. the results of the signature detection may be used by the acoustic echo canceler to stop or restart the adaptation process.

An algorithm for listing all minimal double dominating sets of a tree
PublicationWe provide an algorithm for listing all minimal double dominating sets of a tree of order $n$ in time $\mathcal{O}(1.3248^n)$. This implies that every tree has at most $1.3248^n$ minimal double dominating sets. We also show that this bound is tight.

Examples of retrofit of structures on seismic areas by friction pendulum system.
PublicationZastosowanie łożysk wahadłowych, w których dyssypacja energii następuje na skutek tarcia, to jedna z najbardziej obiecujących metod wzmacniania odporności sejsmicznej budowli. Celem artykułu jest przedstawienie przykładów zastosowania tej metody do różnych typów konstrukcji budowlanych narażonych na wstrząsy sejsmiczne.

An upper bound for the double outerindependent domination number of a tree
PublicationA vertex of a graph is said to dominate itself and all of its neighbors. A double outerindependent dominating set of a graph G is a set D of vertices of G such that every vertex of G is dominated by at least two vertices of D, and the set V(G)\D is independent. The double outerindependent domination number of a graph G, denoted by γ_d^{oi}(G), is the minimum cardinality of a double outerindependent dominating set of G. We prove...

Noise in electrical doublelayer capacitors (EDLCs)
PublicationWe present methods and problems of noise measurements in electrical doublelayer capacitors (EDLC). Detailed noise equivalent electronic circuit is considered, and two possible ways of observations of random processes generated in the EDLCs structures are studied. We conclude that noise is a useful tool for characterization of the EDLC structures and their stateofhealth, as in other materials and electronic devices. Eventual,...

A lower bound on the double outerindependent domination number of a tree
PublicationA vertex of a graph is said to dominate itself and all of its neighbors. A double outerindependent dominating set of a graph G is a set D of vertices of G such that every vertex of G is dominated by at least two vertices of D, and the set V(G)D is independent. The double outerindependent domination number of a graph G, denoted by gamma_d^{oi}(G), is the minimum cardinality of a double outerindependent dominating set of G. We...

On trees with double domination number equal to total domination number plus one
PublicationA total dominating set of a graph G is a set D of vertices of G such that every vertex of G has a neighbor in D. A vertex of a graph is said to dominate itself and all of its neighbors. A double dominating set of a graph G is a set D of vertices of G such that every vertex of G is dominated by at least two vertices of D. The total (double, respectively) domination number of a graph G is the minimum cardinality of a total (double,...

On trees with double domination number equal to 2domination number plus one
PublicationA vertex of a graph is said to dominate itself and all of its neighbors. A subset D subseteq V(G) is a 2dominating set of G if every vertex of V(G)D is dominated by at least two vertices of D, while it is a double dominating set of G if every vertex of G is dominated by at least two vertices of D. The 2domination (double domination, respectively) number of a graph G is the minimum cardinality of a 2dominating (double dominating,...

Application of nonmetal doped titania for inverted polymer solar cells
PublicationDomieszkowany jodem oraz domieszkowany jodem ditlenek tytanu uzyto jako warstwę buforową w ogniwie ITO/XTiO2?P3HTPCMB /MnO2/ Ag.Warswty XTiO2 nalożono metodą spincoatingu z zawiesiny nanocząstek w DMSO. Jednorodne struktury scharakteryzowane pod względem morfologii mikroskopowo metodą AFM. Charakterystyka prądowonapięciowa urzdzeń wskazuje iż domieszkowany jodem TiO2 pozwala osiągnąć lepsze parametry PCE (1,67%) i prąd zwarcia...

Model of the doublerotor induction motor in terms of electromagnetic differential
PublicationThe paper presents a concept, a construction, a circuit model and experimental results of the doublerotor induction motor. This type of a motor is to be implemented in the concept of the electromagnetic differential. At the same time it should fulfill the function of differential mechanism and the vehicle drive. One of the motor shafts is coupled to the direction changing mechanical transmission. The windings of the external rotor...

Thermodynamic analysis of the double Brayton cycle with the use of oxy combustion and capture of CO2
PublicationIn this paper, thermodynamic analysis of a proposed innovative double Brayton cycle with the use of oxy combustion and capture of CO2, is presented. For that purpose, the computation flow mechanics (CFM) approach has been developed. The double Brayton cycle (DBC) consists of primary Brayton and secondary inverse Brayton cycle. Inversion means that the role of the compressor and the gas turbine is changed and firstly we have expansion...

On trees with double domination number equal to 2outerindependent domination number plus one
PublicationA vertex of a graph is said to dominate itself and all of its neighbors. A double dominating set of a graph G is a set D of vertices of G such that every vertex of G is dominated by at least two vertices of D. The double domination number of a graph G is the minimum cardinality of a double dominating set of G. For a graph G=(V,E), a subset D subseteq V(G) is a 2dominating set if every vertex of V(G)D has at least two neighbors...

Thermal and technological aspects of double face grinding of Al2O3 ceramic materials
PublicationDouble face grinding with planetary kinematics is a process to manufacture workpieces with plan parallel functional surfaces, such as bearing rings or sealing shims. In order to increase the economic efficiency of this process, it has to be advanced permanently. The temperature in the contact zone of most grinding processes has a huge influence on the process efficiency and the workpiece qualities. In contrast to most grinding...

The importance of the bottom layer in doublelayer porous asphalt for noise reduction
PublicationDoublelayer porous asphalt concrete (DPAC) surfaces are generally considered to be the acoustically most effective low noise road surfaces ready for implementation. While DPAC used on highways in warm climates may have an average life of around 8 years, in Scandinavia with severe winter climate DPAC usually survive only about 3 years; partly due to wear of studded tyres. An ongoing project in Sweden, applying DPAC and singlelayer...

DoubleBlind Reputation vs. Intelligent Fake VIP Attacks in CloudAssisted Interactions
PublicationWe consider a generic model of ClientServer interactions in the presence of Sender and Relay, conceptual agents acting on behalf of Client and Server, respectively, and modeling cloud service providers in the envisaged "QoS as a Service paradigm". Client generates objects which Sender tags with demanded QoS level, whereas Relay assigns the QoS level to be provided at Server. To verify an object's right to a QoS level, Relay detects...

Experimental investigation on straight and ubend double tube heat exchanger with active and passive enhancement methods
PublicationAuthors in this work want to demonstrate the possibility to increase the heat transfer efficiency by using simple wire coil inserts to create turbulent flow in the boundary layer as well as air blowing into the annulus of the pipe. In the study, Wilson plot approach was applied in order to estimate heat transfer coefficients for all heat exchanger (HX) configurations. The study focuses on experimental values of heat transfer coefficient...

Double Fed Induction Machine Drives
PublicationContents of the Chapter 22:Machine model.Properties of the DFM.Steady state machine operation.Control rules and decoupled control.Decoupling based on MM machine model.Decoupling based on vector model.Decoupling based on rotor current equation.Overall control system.Control system based on MM model.Control system based on vector model.Estimation of variables.Calculation of the angle between stator and rotor.Remarks about digital...

Damage repair of the double shell tank
PublicationPłaszcz wewnętrzny stalowego zbiornika dwupłaszczowego o pojemności 10000 m3 został zdeformowany w wyniku błędu popełnionego podczas próby wodnej przy odbiorze zbiornika. W referacie omówiono technologię naprawy silnie zdeformowanego płaszcza zbiornika. Stosowano roztłaczanie hydrauliczne, prostowanie mechaniczne i termiczne oraz wymianę najbardziej uszkodzonych blach.

Determination of magnetisation conditions in a DoubleCore Barkhausen Noise measurement setup
PublicationThe magnetic Barkhausen effect is useful forassessing 1D and 2D stress states of ferromagnetic steelobjects. However, its extension to technically importantmaterials, such as duplex anisotropic steels, remains challenging. The determination of magnetisation inside the studied object and the electromagnet for various geometries, materials and magnetisation angles is a key issue.Threedimensional, dynamic finite element analysis...

Magnetic and capacitive couplings influence on power and energy measurement in double circuit high voltage overhead transmission line
PublicationThe paper discusses influence of magnetic and capacitive couplings on power and energy measurement in case of double circuit high voltage overhead transmission line. There are presented and discussed various factors influencing the power flow among the line‟s circuits. Mathematical model based calculations results are compared to the real transmission line measurements.

Acoustic lifecycle study of the doublelayer porous asphalt on E4 in Huskvarna, Sweden
PublicationIn 2010 a doublelayer porous asphalt concrete (DPAC) pavement was constructed on the E4 motorway through the Swedish city Huskvarna. Earlier experience in Sweden indicated that it was feasible to obtain a high initial noise reduction but due to the widespread use of studded tires in winter, clogging and ravelling created losses of around 2 dB per year, with an expected acoustical lifetime of only 3 years. However, the improved...

Wideband crossover structure with double ring resonators
PublicationThe structure of a fourport microstrip crossover is presented. The device is composed of two ring resonators, one circular and one built from meander lines, connected by four straight lines. The equivalent circuit model of the crossover is derived. The structure is designed on thin and flexible substrate to allow it to bend. The possibility of applying the device on curved surfaces is tested experimentally.

Stabilization of the pyrochlore phase of Mn2Sb2O7 by double substitution
PublicationPolycrystalline samples of (Ce4+Mn2+3)(Ga3+Sb5+3)O14 were synthesized by a hightemperature solidstate reaction. In contrast with the parent Mn2Sb2O7 compound that adopts a rhombohedral or monoclinic structure at T > 600 °C, the pyrochlore structure of CeMn3GaSb3O14 is retained up to at least T = 1070°C. Highresolution synchrotron xray diffraction measurements show no sign of a superstructure or distortion from cubic symmetry...

Insitu and exsitu resistance measurements of polypyrrole film using doubleband electrode
PublicationMany insitu techniques are performed in order to determine the resistance of conducting polymer film. However, the resistance measured in solution can be the combination of polymer resistance and that of other components, such as resistance of supporting electrolyte. Therefore, in this work, the influence of the solution on the resistance of polypyrrole (PPy) film has been studied. PPy film was electrchemically synthesized onto...

Twophoton double ionization of atoms in attosecond xray radiation fields
PublicationWe consider twophoton double ionization of helium with 100, 200, and 400 eV excess energy for the two ejected electrons, corresponding to photon energies of 89.5, 139.5, and 239.5 eV, respectively. We focus on the case of ultrashort pulses (two oscillations of the field) and develop an approach to calculate the twophoton transition matrix elements within the lowest order of the timedependent perturbation theory. One of the...

DDLMS PCR double digestion Ligation Mediated Suppression PCR  a new technique for bacterial specific differentiation
PublicationA new diagnostic kit for K. oxytoca specific differentiation based on ddLMS PCR (ang. double digest ligation Mediated PCR) technique is shown. As a speciesspecific DNA fragment pehX gene, encoding the enzyme polygalactouronase, was chosen. The genome sequence of K. oxytoca is digested with two endonucleases: AclI and BclI which cut DNA before and after pehX gene. The polymorphic DNA fragments are ligated with AclIendspecific...