A stable adaptive Hammerstein filter employing partial orthogonalization of the input signals

Journal ArticleAbstract This paper presents an algorithm that adapts the parameters of a Hammerstein system model. Hammerstein systems are nonlinear systems that contain a static nonlinearity cascaded with a linear system. In this work, the static nonlinearity is modeled using a polynomial system and the linear filter that follows the nonlinerity is an infinite impulse response system. The adaptation of the nonlinear components is enhanced in the algorithm by orthogonalizing the inputs to the coefficients of the polynomial system. The linear system is implemented as a recursive higher-order filter. The step sizes associated with the recursive components are constrained in such a way as to guarantee bounded-input, bounded-output stability of the overall system. Experimental results included in the paper show that the algorithm performs well and always converges to the global minimum of the input signal is white

Identification of nonlinear, memoryless systems using chebyshev nodes

Journal ArticleABSTRACT This paper describes an approach for identification of static nonlinearities from input-output measurements. The approach is based on minimax approximation of memoryless nonlinear systems using Chebyshev polynomials. For memoryless nonlinear systems that are finite and continuous with finite derivatives, it is known that the error caused by the K th order Chebyshev approximation in a specified interval is bounded by a quantity that is proportional to the maximum value of the (K + 1) th derivative of the inputoutput relationship and decays exponentially with K. The method of the paper identifies the system by first estimating the system output at the Chebyshev nodes using localized linear model around the nodes, and then solving for the coefficients associated with the Chebyshev polynomials of the first kind

A stable adaptive Hammerstein filter employing partial orthogonalization of the input signals

Journal ArticleAbstract-This paper presents an algorithm that adapts the parameters of a Hammerstein system model. Hammerstein systems are nonlinear systems that contain a static nonlinearity cascaded with a linear system. In this paper, the static nonlinearity is modeled using a polynomial system, and the linear filter that follows the nonlinearity is an infinite-impulse response (IIR) system. The adaptation of the nonlinear components is improved by orthogonalizing the inputs to the coefficients of the polynomial system. The step sizes associated with the recursive components are constrained in such a way as to guarantee bounded-input bounded-output (BIBO) stability of the overall system. This paper also presents experimental results that show that the algorithm performs well in a variety of operating environments, exhibiting stability and global convergence of the algorithm

Stochastic mean-square performance analysis of an adaptive Hammerstein filter

Journal ArticleAbstract-This paper presents an almost sure mean-square performance analysis of an adaptive Hammerstein filter for the case when the measurement noise in the desired response signal is a martingale difference sequence. The system model consists of a series connection of a memoryless nonlinearity followed by a recursive linear filter. A bound for the long-term time average of the squared a posteriori estimation error of the adaptive filter is derived using a basic set of assumptions on the operating environment. This bound consists of two terms, one of which is proportional to a parameter that depends on the step size sequences of the algorithm and the other that is inversely proportional to the maximum value of the increment process associated with the coefficients of the underlying system. One consequence of this result is that the long-term time average of the squared a posteriori estimation error can be made arbitrarily close to its minimum possible value when the underlying system is time-invariant

Stochastic mean-square performance analysis of an adaptive Hammerstein filter

Journal ArticleABSTRACT This paper presents an almost sure (a.s.) mean-square performance analysis of an adaptive Hammerstein filter for the case when the measurement noise in the desired response signal is a martingale difference sequence. The system model consists of a series connection of a memoryless nonlinearity followed by a recursive linear filter. It is shown under the conditions of the analysis that the long-term time average of the squared excess estimation error of the adaptive filter can be made arbitrarily close to zero

Does jumping to the beat result in better ratings from gymnastics experts?

How does auditory information influence the perception and evaluation of complex skills? Especially in technical compositional sports, such as gymnastics, the visual information perceived by the judges (and coaches) is the subject of an immediate evaluation. Various factors influence the judges’ performances. The impact of auditory information on the evaluation of complex skills is predominantly unexplored. Therefore, the study aimed to investigate floor music’s role in female gymnastics routines. Participants with different gymnastics expertise were asked to rate acrobatic series on the floor in three different audio-visual conditions (original, inter-beat, matched-beat). The current study results show that participants (irrespective of the group) rated acrobatic series in the matched-beat higher than in the original condition. In conclusion, it would be interesting to investigate if an effect on the participants’ perception is given for other gymnastics skills (gymnastic jumps and leaps) or the overall (execution) score on the floor

Rothko, Malevich, Plato (On a Cruise)

Zdelo se mi je, da lahko nekaj povem o tisti umetnosti, ki se spretno izogiba besedam in ji besede nekako ne pristojijo, brez da zaidem v romantične, patetične in mistične formulacije. Vse skupaj se je začelo z Rothkom — abstraktnim, nefiguralnim slikarjem, ki sklada veličastne barvne štirikotnike. Te slike gledamo kot čisto prezenco nečesa nebesednega. Ideja se je razvijala in najprej se je pridružil Platon, ki v svoji Državi umetnost prežene. Za njim je sledil Malevič s svojim Črnim kvadratom na belem ozadju, ki je Rothku po definiciji podoben (ista reč v črno belem), a mu je hkrati povsem nasproten: Črni kvadrat je koncept. Iz tega nasprotja se je razvila misel, ki se ne boji ustavljati pri metafizičnih parih: umetnost-filozofija, mit-logos, čustva-razum itd. Preko Wajcmana, Heideggra, Derridaja in Schellinga spor med umetnostjo in filozofijo še poglabljam, toda na koncu afirmiram obe, tako da naloga dobi dva konca. A glavni lik je v resnici Platon, ki doživi zanimiv dramatični lok. Začnemo klasično, z njegovim izgonom umetnikov, za kar mu požugamo s prstom, ga oštejemo in preženemo, a na koncu se Platon vrne. Izkaže se, da je še vedno nesmrten. Njegovo vračanje, ki traja že 2500 let, temelji na določeni dvoumnosti v Platonu samem. Skratka: Dva slikarja, dva Platona in dva konca na ladji, ki se odloča med prvo in drugo plovbo.I set out to comment on the sort of art that eludes words and finds them rather unfitting, without plunging into romantic, pathetic, and mystical formulations. Everything started with Rothko — the abstract, non-figurative painter who stacks awe-inspiring color rectangles. We view his paintings as a pure presence of something non-verbal. The first to join Rothko was Plato with his notorious banishing of artists in his Republic. He was followed by Malevich and his Black Square which, by definition, resembles Rothko’s work (the same thing in black and white), but is at the same time completely different: The Black Square is a concept. A thought develops from this opposition that is not afraid to stop at metaphysical dualisms — art and philosophy, myth and logos, reason and emotions etc. Following Wajcman, Heidegger, Derrida and Schelling I delve into the dispute between art and philosophy, in the end affirming both and giving the assignment two endings. The main character, however, is Plato, who has an interesting character arc. We start by presenting his position against art, for which we scold and dispel him. But in the end, it turns out Plato is immortal and he comes back. His ongoing return that has lasted the past 2500 years is due to a certain ambiguity in his own thought. So in short: two painters, two Platos, and two endings on a ship deliberating between the first and second sailing

Attitudes, knowledge and practices of medical students to control of communicable diseases through vaccination

Uvod: Po podatkih Svetovne zdravstvene organizacije se ocenjuje, da s cepljenjem preprečimo med 2 in 3 milijone smrti vsako leto. Zelo pomembno je, da so cepljeni zdravstveni delavci, vključno s študenti zdravstvenih poklicev, ki jih nekatere nalezljive bolezni še bolj ogrožajo. Ti so stalno v stiku z bolniki in nosilci povzročiteljev bolezni. Če se ne cepijo s tem ogrožajo sebe, svoje domače in svoje paciente. Namen: Preučiti stališča, znanja in prakse študentov medicine do obvladovanja nalezljivih bolezni s cepljenjem. Metode dela: Izvedla sem anonimno anketo med študenti 1. in 6. letnika Medicinske fakultete Univerze v Mariboru (skupaj 160 študentov) v študijskem letu 2015/2016 v aprilu in maju 2016. Opravila sem deskriptivno analizo zbranih odgovorov. Rezultati: Vprašalnik je izpolnilo 109 (68%) študentov. Vsi anketirani študenti šestega letnika zaupajo cepljenju in cepivom. 95% anketiranih študentov 6. letnika meni, da so cepiva varna in ne ogrožajo zdravja otrok. Le 1% študentov prvega in 5% študentov šestega letnika se redno cepi proti gripi. 16% študentov 1. in 21% študentov 6. letnika bi se odločilo za cepljenje proti hepatitisu B tudi, če to ne bi bilo obvezno. Razprava in zaključek: Znanje študentov medicine, ki so sodelovali v raziskavi ni bilo zadovoljivo. Anketirani študenti niso prepoznali takšne stopnje pomembnosti cepljenja kot bi si želela stroka, zato bo na tem področju potrebna okrepitev programa izobraževanja študentov. Rezultati moje raziskave bodo služili kot osnova za spremljanje stanja in predstavljali izhodišče za nadaljnje bolj podrobne raziskave na tem področju.Introduction: According to the World Health Organization, it is estimated that between 2 and 3 million deaths are prevented each year through immunization. It is very important that health care workers (including students of health professions) are vaccinated due to higher risk of infectious diseases. They are in constant contact with patients and carriers of pathogens, thererefore if they do not vaccinate they endanger themselves, their family/friends and their patients. Purpose: To study the attitudes, knowledge and practices of medical students to control of communicable diseases through vaccination. Methods: I conducted anonymous survey among students of 1st and 6th grade of the Medical Faculty of the University of Maribor (a total of 160 students) in the academic year 2015/2016 in April and May 2016. I have done a descriptive analysis of the collected answers. Results: The questionnaire was responded by 109 (68 %) students. All 6th grade students trust in vaccination and vaccines. 95 % of 6th grade students believe that vaccines are safe and do not endanger the health of children. Only 1% of 1st grade students and 5% of 6th grade students are regularly vaccinated against the flu. 16 % of 1st grade students and 21 % of 6th grade students would opt for vaccination against hepatitis B, even if this would not be mandatory. Discussion and conclusion: Knowledge of medical students who participated in the survey was not satisfactory. The surveyed students did not recognize the importance of vaccination as we would like, therefore, there will still be needed more activities to improve that. The results of this work will serve as a basis for monitoring and a starting point for further more detailed research in this area

Energy balance of chosen apartment building with suggestions for improvement

The purpose of this diploma thesis is the energy balance calculation of an apartment building in\ud Logatec, at the address Sončni log 1 and 1a. This data represents the energy efficiency or inefficiency\ud of the apartment building and can be used to introduce renovation possibilities, with which the criteria\ud of an energy efficient building, according to the Regulations on Energy Efficiency in\ud Buildings (PURES 2010, Ur. l. RS, nr. 52/2010: 7840), can be met. . The calculations were carried out\ud using the KI Energija software that is based on the methodology of the Regulations PURES 2010 and\ud the directive Tehnična smernica - učinkovita raba energije (TSG nr. 1-004, 2010). Also carried out\ud was a comparison of the actual U-factors with those in effect at the time of construction planning,\ud because of the inadequate values of thermal transmittance factors of constructional complexes. The KI\ud Energija computer software recorded energy balance calculations which indicate energy efficiency.\ud The chosen building’s energy balance does not meet the criteria of PURES 2010, because the\ud legislation in effect at the time of construction planning, in 2005, involved criteria that were less strict.\ud The most substantial deviations occur in the split-level constructional complex, which divides the\ud heated zone and the garage, because it is not thermally insulated and the U-factor exceeds the\ud threshold by 1,1 W/(m2K). The most energy-efficient renovation measures include additional thermal\ud insulation of split-level constructional complexes and the non-permeable exterior, while also installing\ud a mechanical ventilation system with heat recovery

Experimental analysis of salt effects on the effectiveness of modified sea clay with lime for embankment construction

V Luki Koper je potrebno stalno vzdrževanje in poglabljanje morskih plovnih poti. Pri tem nastanejo velike količine mešanice gline in vode, ki se odlagajo v namensko zgrajenih bazenih na kopnem, kjer se trdni delci usedejo, voda pa odteka nazaj v morje. Lokalno ime za proces je »refuliranje«, material v procesu pa »reful«. Obravnavani način ravnanja z refulom zavzema velike površine na kopnem, zato Luka Koper išče alternativne rešitve za boljšo rabo tega materiala. Ena od rešitev je izboljšanje lastnosti refula z ožemanjem in dodajanjem veziv. V nalogi smo raziskovali možnost izboljšanja lastnosti refula z apnom ter vplive soli na lastnosti mešanic apna in refula. Za določitev vplivov soli na delovanje apna, so bili odvzeti vzorci pripravljeni na tri načine: (a) s pranjem je bila iz refula odstranjena vsa sol, (b) uporabljen je bil naravno slan reful in (c) reful je bil negovan v zasičeni solni raztopini. Iz tako pripravljenih vzorcev so bile izdelane mešanice z apnom in izvedene laboratorijske preiskave: Atterbergove meje plastičnosti, enoosna tlačna trdnost, vodovpojnost po metodi Enslin-Neff, meja krčenja, sukcija, pH vrednost, metilen modro, Proctorjev preskus in kalifornijski indeks nosilnosti (CBR) ter nabrekanje. Raziskave so pokazale, da sol v porni vodi pozitivno vpliva na obnašanje refula, če je vlaga materiala blizu optimalne vlage. Sol zniža plastičnost, sposobnost navzemanja vode in kationsko izmenjalno kapaciteto zemljine ter zniža optimalno vlago in zviša maksimalno suho gostoto. Pri raziskavah ni bilo zaznati morebitnih škodljivih vplivov soli na obnašanje z apnom izboljšane zemljine.The port of Koper requires constant maintenance and deepening of the sea waterways. This produces large amounts of a clay-water mixture, which is deposited in purpose-built onshore basins where solid particles settle and the water flows back into the sea. The local name for the process is "reful" and the material in the process is "reful". The discussed method of handling reful occupies large areas on land, which is why Luka Koper is looking for alternative solutions for a better use of this material. One solution is to improve reful properties by filtrating and adding binders. In the paper, we explored the possibility of improving the properties of reful with lime and the effects of salt on the properties of mixtures of lime and reful. To determine the effects of salt on the action of lime, the samples taken were prepared in three ways: (a) by washing all salt was removed from reful, (b) naturally salty reful was used and (c) reful was nourished in a saturated salt solution. From the samples thus prepared, lime mixtures were prepared and laboratory tests were carried out: Atterberg plasticity limits, uniaxial compressive strength, Enslin-Neff method of water absorption, shrinkage limit, suction, pH value, methylene blue, Proctor test and California load index (CBR), and swelling. Research has shown that salt in pore water has a positive effect on the behaviour of reful when the moisture of the material is close to optimal moisture. Salt reduces the plasticity, water absorption capacity and cation exchange capacity of the soil and lowers optimum moisture and increases maximum dry density. The research did not detect any potential adverse effects of salt on the behaviour of the lime-improved soil