UNIVERSAL MICROPROCESSOR CONTROLLED POWER REGULATOR WITH AND WITHOUT ADDITIONAL POWER SUPPLY

Inexpensive microcontrollers allow complex control methodologies for improving well-established technologies such as resistive lighting. In this paper, we present two constructions of a microprocessor controlled power regulator for resistive load of up to 2.5 kW and exemplify its use for the lamps in Tesla’s Fountain reconstruction project. These are universal power controllers and could be applied to a wide verity of non-inductive loads, but our primary intention was to construct a miniature light regulator with touch sensor for Tesla’s Fountain. The devices operate using the phase control of the power grid’s alternating current and controlled fade-in to increase lamp longevity. Extensive testing shows the device to operate successfully for 2400 hours of continuous error-free operation, to robustly handle high cycling stresses and increase bulb lifetimes by approximately a factor of 7-8. The microcontroller software can easily be adapted for controlling many non-inductive apparatus, like light bulbs or halogen lamps, as well as resistive heating. We also used advanced technologies from other multi-disciplinary areas to complete project

Ultra-fast basic geometrical transformations on linear image data structure

This paper presents a general, ultra-fast approach for geometrical image transformations, based on the usage of linear lookup hash tables. The new method is developed to fix distortions on document images as part of a real-time optical character recognition (OCR) system. The approach is generalized and uses linear image representation combined with pre-computed lookup tables. Backward mapping is used for generation of lookup tables, while forward mapping is presented as an alternative and more efficient mapping model for specific cases. Also, a theoretical space and time complexity analysis of the proposed method is provided. To achieve maximal computational performance, pointer arithmetic and highly-optimized low-level machine code implementations are provided, including the specialized implementations for horizontal mirror, vertical mirror, and 90° rotation. Also, a modified variant of the approach, based on auto-generated machine code is presented. Very high computational performances are achieved at the expense of memory usage. The performances from the perspective of time complexity are analyzed and compared with classical implementation, FPGA implementation, and other implementations of the image rotation. Numerical results are given for a set of different PC specifications to provide full insight into the implementation performances. The processing time for very large images are below 200 ms for backward mapping and below 100 ms for forward mapping for most machines, which is 30–60 times faster than the classical implementation, 5–20 times faster than the FPGA implementation, and up to 6 times faster than other implementations of image rotation. Original documents belonging to Nikola Tesla are used for visual demonstration of performance.</p

3-D STEREOSCOPIC MODELING OF THE TESLA'S LONG ISLAND

This paper presents in detail the methods for realization of the basic software infrastructure for the conversion of 3-D animation of Tesla’s laboratory in Long Island to modern stereoscopic 3-D formats. Modeling of Tesla’s lab is done in cooperation with the Nikola Tesla Museum in Belgrade on a project entitled “Computer Simulation and Modeling of the Original Patents of Nikola Tesla”  approved by the Ministry of Education and Science of the Republic of Serbia. In recent years, there has been a revolution in the field of 3-D technology, so it is clear that this will be the strategic direction of the progressing of television, cinema screenings and presentations in the future. Using modern technology for generating and conversion to stereoscopic 3-D format, the authors show in detail the procedure that was used in the realization of this segment of the project. The complete improved 3D developing pipeline from the original photograph to the stereoscopic 3D real-time model is also presented. The novelty in the phase of semiautomatic materialization of the wire models is also described

EFFICIENT IMAGE COMPRESSION AND DECOMPRESSION ALGORITHMS FOR OCR SYSTEMS

This paper presents an efficient new image compression and decompression methods for document images, intended for usage in the pre-processing stage of an OCR system designed for needs of the “Nikola Tesla Museum” in Belgrade. Proposed image compression methods exploit the Run-Length Encoding (RLE) algorithm and an algorithm based on document character contour extraction, while an iterative scanline fill algorithm is used for image decompression. Image compression and decompression methods are compared with JBIG2 and JPEG2000 image compression standards. Segmentation accuracy results for ground-truth documents are obtained in order to evaluate the proposed methods. Results show that the proposed methods outperform JBIG2 compression regarding the time complexity, providing up to 25 times lower processing time at the expense of worse compression ratio results, as well as JPEG2000 image compression standard, providing up to 4-fold improvement in compression ratio. Finally, time complexity results show that the presented methods are sufficiently fast for a real time character segmentation system

Fractal Simulator and Ceramics Technology for New Tesla’s Fountain

In this study, we present new Tesla’s Fountain model in ceramics technology. It is reconstructed from basic 3D model. The model is designed based on Tesla’s original US patent no. 1,113,716, granted on October, 13 (1914). The complete model includes the engine (rotating water pump), colored lights and fluids. This part of the paper is based on research within the project entitled “Computer Simulation and Modeling of the Original Patents of Nikola Tesla” and approved by the Ministry of Education, Science and Technological Development of the Republic of Serbia. The first Tesla's patent that was under our attention in this project was Tesla’s Fountain that is presented in this paper. It is well known that first Tesla’s experiments on Fountain have been realized in materials like bronze-metal. Nevertheless, we used new approach and applied ceramics materials technologies in combination of casting and sintering. We used our original fractal simulator to observe and simulate micro particles movements in Fountain model Finally, we used smoothed-particle hydrodynamics (SPH) as a method of computation and simulating the dynamics of continuum media, like the flow of fluids. The method was developed by Gingold, Monaghan and Lucy in 1977, initially for astrophysical problems. It is also used in astrophysics, ballistics, volcano logy, and oceanography but we find new appliance in our Fountain model. We combine a mesh-free Lagrange method (coordinates move with the fluid) to easily adjust resolution of the simulation with respect to all variables (like the density)

Prevalencija karijesa kod bolesnika hospitalizovanih zbog shizofrenije

Background/Aim. It is considered that over 450 million people worldwide suffer from some form of mental disorder. Previous studies in other countries have shown that schizophrenia is among the most frequent. Oral health is significant for general health and should not be separated from mental health. Studies in other countries have shown an increased incidence of carious and extracted teeth, and less incidence of filled teeth in this group of psychiatric patients. The aim of this study was to establish condition of the existing teeth, to determine the prevalence of caries and to consider possible risk factors that contribute to the current oral health status of hospitalized patients with schizophrenia. Methods. The study comprised 190 patients with schizophrenia, hospitalized at the Clinic for Psychiatric Disorders 'Dr. Laza Lazarević' in Belgrade, and 190 mentally healthy patients at the Clinic for Periodontology and Oral Medicine, Faculty of Dental Medicine in Belgrade. The decayed, missing, filled (DMF) index, sociodemographic and economic characteristics were registered in both groups, as well as characteristics of the primary disease of hospitalized patients with schizophrenia. Results. The value of DMF index (representing the sum of carious, extracted and filled teeth), in the hospitalized patients with schizophrenia was 18.57 ± 7.07 and 12.47 ± 5.64 in the healthy group (p = 0.000). The structure of the DMF index in the study group showed that caries and extracted teeth dominated with 88.1%; in the control group, filled teeth dominated with 55.6%, which was a statistically significant difference for all the three observed variables. Conclusion. Hospitalized patients with schizophrenia had twice as many caries and extracted teeth, and five time less filled teeth than healthy people. The patient's age and taking antiparkinsonics were established as predictors of the increased DMF index in hospitalized patients with schizophrenia.Uvod/Cilj. Smatra se da preko 450 miliona ljudi širom sveta pati od nekog oblika mentalnog poremećaja, a istraživanja sprovedena u drugim zemljama pokazala su da je shizofrenija među najzastupljenijima. Oralno zdravlje zauzima značajno mesto u celokupnom zdravlju čoveka i ne treba ga razdvajati od mentalnog zdravlja. Istraživanja sprovedena u drugim zemljama pokazala su povećanu zastupljenost karijesnih i izvađenih zuba, a manje plombiranih zuba kod ove grupe psihijatrijskih bolesnika. Cilj studije bio je da se istraži stanje prisutnih zuba, odredi prevalencija karijesa i ispitaju mogući faktori rizika koji doprinose postojećem stanju oralnog zdravlja kod bolesnika hospitalizovanih zbog shizofrenije. Metode. U istraživanju je učestvovalo 190 bolesnika sa shizofrenijom, hospitalizovanih na Klinici za psihijatrijske bolesti 'Dr Laza Lazarević' u Beogradu i 190 mentalno zdravih ispitanika, pacijenata Klinike za parodontologiju i oralnu medicinu Stomatološkog fakulteta u Beogradu. Ispitanicima obe grupe registrovane su vrednosti KEP indeksa, sociodemografske i ekonomske karakteristike, a bolesnicima hospitalizovanim zbog shizofrenije i karakteristike primarne bolesti. Rezultati. Vrednost KEP indeksa kod bolesnika hospitalizovanih zbog shizofrenije iznosila je 18,57 ± 7,07, a kod zdravih osoba 12,47 ± 5,64 (p = 0,000). U strukturi indeksa koji pokazuje zbir brojeva karioznih, ekstrahovanih i plombiranih zuba (KEP) kod bolesnika sa shizofrenijom, dominirali su karijesni i ekstrahovani zubi - 88,1%, a u kontrolnoj grupi plombirani zubi - 55,6%, što je bila statistički značajna razlika za sve tri posmatrane varijable. Zaključak. Bolesnici hospitalizovani zbog shizofrenije imali su dvostruko više karijesnih i izvađenih zuba, a pet puta manje plombiranih zuba od zdravih osoba. Kao prediktori povećanog KEP indeksa kod bolesnika hospitalizovanih zbog shizofrenije ustanovljeni su starost ispitanika i korišćenje antiparkinsonika

Ultra-fast basic geometrical transformations on linear image data structure

This paper presents a general, ultra-fast approach for geometrical image transformations, based on the usage of linear lookup hash tables. The new method is developed to fix distortions on document images as part of a real-time optical character recognition (OCR) system. The approach is generalized and uses linear image representation combined with pre-computed lookup tables. Backward mapping is used for generation of lookup tables, while forward mapping is presented as an alternative and more efficient mapping model for specific cases. Also, a theoretical space and time complexity analysis of the proposed method is provided. To achieve maximal computational performance, pointer arithmetic and highly-optimized low-level machine code implementations are provided, including the specialized implementations for horizontal mirror, vertical mirror, and 90° rotation. Also, a modified variant of the approach, based on auto-generated machine code is presented. Very high computational performances are achieved at the expense of memory usage. The performances from the perspective of time complexity are analyzed and compared with classical implementation, FPGA implementation, and other implementations of the image rotation. Numerical results are given for a set of different PC specifications to provide full insight into the implementation performances. The processing time for very large images are below 200 ms for backward mapping and below 100 ms for forward mapping for most machines, which is 30–60 times faster than the classical implementation, 5–20 times faster than the FPGA implementation, and up to 6 times faster than other implementations of image rotation. Original documents belonging to Nikola Tesla are used for visual demonstration of performance.</p

Tesla's Fountain – Modeling and simulation in ceramics technology

In this paper, we present Tesla's Fountain in ceramics technology reconstruction from basic 3D model, simulation of the engine, light and fluids till the real materialization. As the one of the most important model purposes, we enrich this solution by additional multicolor lights. All of this elements are designed based on Tesla's original patent no. 1,113,716, US patent office, granted Oct,13. In this model we applied ceramics technology based on ceramic materials casting and sintering. At the time when the patent was granted, the metal materials science and technologies were more advanced than the ceramics technology and applications. We performed all materials characteristics analyses and preparation steps based on the one author's patent no. 46121, Serbia patent office, granted 21.12.1991. This is one original two patents solution with complete new over-bridging by the state-of-the-art computer modeling and simulation technology. © 2018 Elsevier LtdThis is the peer-reviewed version of the article: Vuckovic, V., Mitic, V.V., Kocic, L., Arizanovic, B., Paunovic, V., Nikolic, R., 2018. Tesla’s Fountain – Modeling and simulation in ceramics technology. Journal of the European Ceramic Society 38, 3049–3056. [https://doi.org/10.1016/j.jeurceramsoc.2018.01.041

Električna vozila

Električna vozila / [autori: Aleksandar Despić, Dragutin Dražić, Vladan Vučković, Jovan Todorović ; urednik: Mirjana Jevremović]. – Beograd : Institut tehničkih nauka Srpske akademije nauka i umetnosti. Biro za autonomna električna vozila (Beograd : Jugoslovensko udruženje „Nauka i društvo“), 1981. – 41 str. : ilustr. ; 30 c

Analiza proizvodnih karakteristika i mikroklimatskih parametara na farmama za proizvodnju mleka

Aiming determination of the variability of production traits (daily milk yield and composition) and microclimate parameters (ambient temperature and humidity) in the barns; as well as the correlation between the analyzed groups of traits, 1,636,192 test-day records from Simmentals and 1,275,713 test-day records from Holsteins were analysed. Performed analysis indicate high variability of production traits due to cow's breed, parity as well as breeding region. Also, high variability of microclimate parameters in the barns due to season and breeding region was found. Furthermore, statistically highly significant (p lt 0.001) correlations between the production traits and microclimate parameters were determined. Finally, the negative effect of inadequate microclimate on daily milk production was determined in both breeds in all breeding regions. Since genetic evaluation and selection of dairy cattle for heat resistance is only long-term method for heat stress managing, determined effect will be taken into account in the statistical model for estimation of genetic parameters and breeding values.Cilj istraživanja je bio određivanje varijabilnosti proizvodnih osobina (dnevni prinos i sastav mleka) i mikroklimatskih parametara (temperatura i vlažnost okoline) u objektima za držanje krava za proizvodnju mleka; kao i korelacija između analiziranih grupa osobina; 1.636.192 zapisa za grla simentalske rase i 1.275.713 zapisa test dana grla holštajn rase. Izvršene analize pokazuju veliku varijabilnost proizvodnih osobina zbog rase krava, pariteta kao i odgajivaĉkog regiona. Takođe je utvrđena velika varijabilnost mikroklimatskih parametara u objektima zbog sezone i odgajivačkog regiona. Pored toga, utvrđene su statistički vrlo značajne (p lt 0,001) korelacije između proizvodnih svojstava i parametara mikroklime. Konačno, negativan uticaj neadekvatne mikroklime na svakodnevnu proizvodnju mleka utvrđen je kod obe rase u svim odgajivačkim regionima. Pošto je genetska procena i selekcija mlečnih goveda na otpornost na visoke temperature sredine samo dugoročna metoda za upravljanje toplotnim stresom, utvrđeni efekat biće uzet u obzir u statističkom modelu za procenu genetskih parametara i odgajivačkih vrednosti