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In the paper Serbia’s Law on Determining the Origin of Property and the Special Tax is analysed and compared with solutions based on cross-checking of the declared income with the worth accretion, which can be found in comparative tax law. After having established the advantages and limits of the net worth method, the author presents this Serbian statute, pointing out the fact that significant resources have been allocated for its application. The explanation lies in its PR impact and the possibility that detected unreported income of those who are the Government’s political opponents could be taxed at a rate of 75%. Net worth method has been present in another Serbian statute since 2003, but it was not applied due to the absence of political will. However, this provision remains in the system, providing for dualism since 2021 – one group of taxpayers is subject to the old regime (with 20% tax), while the others are exposed to new confiscatory 75% tax. The analysis shows that numerous provisions of the 2021 statute contradict constitutional provisions on the unity of legal order, nondiscrimination, legality of taxes, and prohibition of retroactivity. Provided these flaws are eliminated, the application of net worth method could make sense., U ovom se radu analizira srpski Zakon o utvrđivanju porekla imovine i posebnom porezu iz 2021. i uspoređuje s rješenjima koja se pronalaze u usporednom poreznom pravu, a koja se temelje na unakrsnoj procjeni prijavljenoga dohotka i porasta neto imovine. Nakon što su utvrđene prednosti i ograničenja, tzv. net worth metode, autor ukazuje na to da je zakonodavac izdvojio znatne resurse za primjenu Zakona, računajući na propagandni učinak i mogućnost da otkriveni neprijavljeni dohodak fizičkih osoba, koja mogu biti i politički oponenti vlasti, bude oporezovan po stopi od 75 %. Još od 2003., tzv. net worth metoda je zastupljena u Zakonu o poreskom postupku i poreskoj administraciji, ali se ne primjenjuje zbog nedostatka političke volje. Paradoksalno je što je ta odredba zadržana u sustavu, tako da od 2021. postoji dualizam – za jedne će obveznike i dalje vrijediti odredbe iz 2003. (s porezom od 20 %), a za druge novi zakon, s gotovo konfiskatornom stopom. Analiza pokazuje da su brojne odredbe zakona iz 2021. suprotne s odredbama Ustava – o jedinstvu pravnoga poretka, zabrani diskriminacije, načelu zakonitosti poreza i nedopuštenosti retroaktivnosti zakona. Ako bi se uklonili navedeni nedostatci, primjena, tzv. net worth metode bi imala smisla.

The workshop is structured to have a theoretical introduction and subsequent application oriented hands-on demonstrations. The workshop is planned to include continuous interactive discussion. The workshop will focus on non-invasive options for the control of paralyzed arm-hand complex after the central nervous system lesion (brain lesion, cervical lesion of the spinal cord, and similar). The workshop starts with theory describing the principle of the operation of functional activation of paralyzed muscles by means of electrical field and differences between the use of transcutaneous and implantable technologies. The results on the efficacy of FES augmented manipulation and grasping, with the emphasis on what were the limitations of the systems applied, will follow. The main questions that will be answered deal with methods to provide sufficient selectivity, minimize muscle fatigue, and have the control that matches the needs of users. The practical part will be a demonstration of the strategies and limitations of the surface activation of arm muscles to support the exercise, manipulation and exercise. The presentation will include the activation of sensory pathways for possible feedback applications. An interesting example will be described where the FES technology can be used for the reduction of tremor. The practical part will be with the new stimulators MOTIMOVE (https://www.3-x-f.com/products.php) and UNAFET stimulators used in clinical trials for therapy persons after stroke and spinal cord lesion at the cervical level.

We describe the use of an insole with five pressure sensors having small hysteresis, an inertial measurement unit, and the circuitry for wireless synchronized communication for the rule-based control of gait. The system was tested with the multichannel electronic stimulator MOTIMOVE that can receive signals from analog and digital sensors to activate up to eight muscle groups. The rule-based control implements the heuristically determined mapping of the four joint states (blocked -B, flexion - F, extension - E, loose - L) and Gait Teacher based representation of the events and phases of the gait cycle. The four joint states can be achieved by the activation of flexors (F), extensors (E), coactivation of flexors and extensors (B), and no action (L). The feasibility of the operation was tested only in a small number of persons with hemiplegia since the stimulator certification procedure required for the full clinical study is in progress

Analysing the ground reaction force (GRF) is an important component in rehabilitation medicine evaluation. Force platemeasurements remain the gold standard but wearable systems are gaining precision and reproducibility allowing for relevant in-field analysis. The Gait-Teacher custom made by Rehabshop (Belgrade), is an insole with embedded industrial quality pressure sensors and one 3D inertial measurement unit (IMU). Typically, coupling the pressure sensors and IMU may help in assess the GRF. The hypothesis was that from the instrumented insole data we can estimate the horizontal and vertical components of the GRF during the loading and push-off phases of the gait cycle. One healthy subject was walking at self-selected pace and data from the wearable system were validated against reference data obtained from a motion analysis system and a force plate. We found that the insole could estimate correctly the GRF during the loading phase but not during the push-off phase, probably due to the need to further optimize sensor position in the insole.

Clinical decision support system represents a computer-aided tool that utilizes advanced technologies for influencing clinical decisions about patients. This dissertation presents research and development of a new decision support system for the assessment of patients with neurodegenerative diseases. The analysis of movements that are part of standard clinical scales or everyday activities represents the basis of the system. These movements are recorded using small and lightweight wearable, wireless sensors, which do not require complicated setup and can be easily applied in any environment. The first part of system is dedicated to the (early) recognition of Parkinson’s disease (PD) based on gait analysis and deep learning algorithms. PD patients could be identified with a high accuracy. The other part of the system is dedicated to the assessment of PD symptoms, more specifically, bradykinesia, utilizing the knowledge-based reasoning. A method for analysis of bradykinesia related movements is defined and presented. Moreover, by applying different signal processing techniques, new metrics have been developed to quantify the essential characteristics of these movements. The prediction of symptom severity was performed using new expert system that completely objectified the clinical evaluation criteria. Validation was performed on the example of the finger-tapping movement of patients with typical and atypical parkinsonism. A high compliance rate was obtained compared to clinical data. The developed system is objective, automated, easy to use, contains an intuitive graphical and parametric presentation of results, and significantly contributes to the improvement of clinical assessment of patients with neurodegenerative diseases.

Recording of the smooth stomach muscles' electrical activity can be performed by means of Electrogastrography (EGG), a non-invasive technique for acquisition that can provide valuable information regarding the functionality of the gut. While this method had been introduced for over nine decades, it still did not reach its full potential. The main reason for this is the lack of standardization that subsequently led to the limited reproducibility and comparability between different investigations. Additionally, variability between many proposed recording approaches could make EGG unappealing for broader application. The aim was to provide an evaluation of a simplified recording protocol that could be obtained by using only one bipolar channel for a relatively short duration (20 minutes) in a static environment with limited subject movements. Insights into the most suitable surface electrode placement for EGG recording was also presented. Subsequently, different processing methods, including Fractional Order Calculus and Video-based approach for the cancelation of motion artifacts – one of the main pitfalls in the EGG technique, was examined. For EGG, it is common to apply long-term protocols in a static environment. Our second goal was to introduce and investigate the opposite approach – short-term recording in a dynamic environment. Research in the field of EGG-based assessment of gut activity in relation to motion sickness symptoms induced by Virtual Reality and Driving Simulation was performed. Furthermore, three novel features for the description of EGG signal (Root Mean Square, Median Frequency, and Crest Factor) were proposed and its applicability for the assessment of gastric response during virtual and simulated experiences was evaluated. In conclusion, in a static environment, the EGG protocol can be simplified, and its duration can be reduced. In contrast, in a dynamic environment, it is possible to acquire a reliable EGG signal with appropriate recommendati

New binary catalytic systems based on sulphated zirconia-alumina were synthesized by controlled hydrolysis of alkoxides using relative molar ratios of constituents 1:1, 1:2 and 1:3 in favour of zirconia. The obtained differences in the final catalytic material’s properties may be related to organic precursor memory effect, the applied calcinations temperatures and used alumina contents. The addition of alumina to zirconia affected the structural and surface properties stabilizing bare zirconia by means of slower phase transformation of tetragonal zirconia crystal phase into monoclinic one, further resulting in smaller crystallites sizes and higher surface density of acidic function (sulphates). The best alumina impact on physico-chemical properties was achieved when the highest amount of alumina (e.g. 50%) and lower calcination temperature (500°C) were used, causing relatively high steady-state activity in isomerization of n-hexane at reaction temperature 250 °C. On the other hand, higher calcination temperature (600 °C) played a role in the genesis of greater sulphate density. Catalytic activity and selectivity are expressed as a complex synergistic function of relative density of acid sites together with positive status of other optimized physico-chemical properties of the catalytic material (by activation and calcination temperatures).

The educational system allowing creative thinking, life-long learning, mobility and the boosting self-confidence is an essential component of the productive economy and better quality of life. The educational system based on the Bologna declaration is being implemented in most European countries to meet the needs. The current higher education uses the European Credit Transfer System (ECTS) with the 180 ECTS credits for Ph.D. school following MS degree with 300 ECTS credits (MS and BS). In parallel, the governments introduced classifications of jobs to complement the three higher education degrees. The change in the educational system should be the reflection of the society needs; however, in some countries, this is not the case. More precisely, the societal and economic changes are not synchronized with the new educational system resulting in the graduates not being needed on the job market and in insufficient number of experts for the needs of the existing market. The message of this presentation is that a new degree which certifies the know-how and experience in economy-oriented discipline is a possible method to overcome the problem of unsynchronized education and market needs.

The gait restoration is a significant component of the rehabilitation of patients with hemiplegia after central nervous system lesion. The typical symptom of the disability is the lack of hip extension during the stance phase and hip flexion during the swing phase of the affected leg; therefore, asymmetry and perturbed balance while walking. We developed a new modular orthosis for assisting hip flexion and extension during the therapeutic sessions of the gait in hemiplegic individuals based on thorough analysis of the gait characteristics of normal gait. The system is designed to fit into the powered postural controller Walkaround®. The system is developed based on the estimation of torque and power requirement for the gait at speeds up to 1.1 m/s. The model used for the simulation is a known double pendulum in the sagittal plane. The kinematics and dynamics used as the input for the simulation have been recorded in the gait laboratory with eight cameras and force platforms. The system needs to be clinically evaluated before it possibly can be turned into innovation. © 2018, University of Kragujevac, Faculty of Science.

The development of a comprehensive computational model of the pendulum test which is appropriate for the analysis of the pathologic behavior of the leg in humans with the central nervous system (CNS) lesion is presented in this review. The model relates to the pendulum movement of the lower leg (shank and the foot) in the lateral plane due to the gravity and involuntary contractions of the muscles. The viscous damping and elastic stiffness reflect the soft tissues and friction in the knee joint. To quantify the pathologic activity of paralyzed muscles a reflex torque was added to the gravity generated knee joint torque. The knee joint encoder, accelerometers and gyroscopes positioned along the shank and thigh, and EMG amplifiers were used to acquire data for the illustration of the validity of the model. We show that the linear model of the movement of the lower leg is not a good representation of the motor impairment. We show that the model expanded with the reflex torque affecting the movement is well suited for the pendulum analysis. The timing of the reflex torques can be determined from the EMG recordings. © Serbian Journal of Electrical Engineering. 2018.

Конвенционална површинска електромиографија (сЕМГ) је метод процене мишићне активности. Конвенционални сЕМГ даје локалну слику и јако зависи од положаја електрода у односу на мишић. Да би се добила прецизнија слика мишићне активности погодна је примена матричних електрода и мерење напона између елемента матрице и једне референтне тачке. У овој тези је приказана примена нових типова матричних електрода и унапређења анализе просторно-временске расподеле активности мишића. Резултати тезе омогућују унапређење терапије пацијената са сензорно-моторним дефицитом.Један циљ истраживања је било унапређење управљањем мултифункционалном трансрадијалном протезом. У истраживањима смо показали да примена 24-каналног минијатурног уређаја (Smarting, mBrainTrain, Београд) и електрода са 24 проводна поља дизајнирана у лабораторији у сарадњи са предузећем Tecnalia Serbia, Београд омогућује поновљиво снимање ЕМГ мапа. Алгоритам који смо развили користи природну корелацију просторних и темпоралних синергија мишића са кинематиком хода и може директно да се примени за управљање активним мултифункционалним трансрадијалним протезама и роботским хватаљкама.Друга примена наших метода и инструментације је за праћење опоравка у рехабилитацији пацијената са поремећајима у ходу. Показали смо да метода омогућује праћење елемената симетрије мишићних активности уз истовремено снимање механике хода. Показали смо да ЕМГ мапе омогућују анализу правилности покрета у односу на облик који карактерише правилан покрет.Трећа примена коју смо развили омогућује да миметички пренесемо активност измерену на здравом екстремитету на паретични или парализовани екстремитет. Ова техника омогућује селективну функционалну електричну стимулацију. Метод смо проверили са новим електродама на пацијентима после можданог удара., Conventional surface electromyography (sEMG) is a method of assessing muscle activity. Conventional sEMG gives a local image and depends on the position of the electrodes in relation to the muscle. To obtain a better picture of muscle activity, it is suitable to use array-electrodes and measure the voltage between the array elements and one reference point. We present the application of new types of array-electrodes and the improved analysis of the spatial-temporal distribution of muscle activities. The results of the thesis are suitable for the improved therapy of patients with sensory-motor deficit.One goal was to improve the myoelectric control of the multifunctional transradial prosthesis. We show that the 24-channel wearable amplifier (Smarting, mBrainTrain, Belgrade) and the 24-pad electrode designed in our Lab in collaboration with Tecnalia Serbia, Belgrade allow reproducible recording of sEMG. The algorithm we developed uses the correlation of spatio-temporal muscle synergies with gait mechanics and has a direct application for control of multifunctional transradial prosthesis.Second application of our methods and instrumentation is to monitor recovery in the rehabilitation of patients with gait disorders. We have shown that the method allows monitoring the elements of symmetry of muscle activities while recording the gait mechanics. We have shown that EMG maps allow the analysis of the regularity of movement in relation to the shape that characterizes the correct movement.Third application of the research results allows a transfer of target zones determined from the activity measured on a healthy limb to a paralyzed limb. This technique allows effective selective functional electrical stimulation. We tested the method with new electrodes on patients after stroke.