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Acceleration of Object Tracking Algorithms
No full textObjektų sekimo vaizde algoritmų spartinimas. Magistro baigiamasis darbas elektronikos inžinerijos laipsniui. Vilniaus Gedimino technikos universitetas. Vilnius, 2018, 61 p., 25 iliustr., 7 lent., 37 bibl., 2 priedai. Naujausi objektų sekimo vaizde algoritmai veikia vis tiksliau, tačiau tik nedidelė dalis jų gali veikti realiu laiku. Baigiamojo darbo tikslas – padidinti objektų sekimo algoritmo spartą. Tikslui pasiekti bandyta keisti objektų aptikimo dažnumą bei objektų aptikimo algoritmo architektūrą. Tyrimo objektu pasirinkti pėstieji. Iškelti uždaviniai yra įvykdyti – atlikus eksperimentinius tyrimus ir esamo algoritmo derinimą gauta sistema, galinti sekti pėsčiuosius vaizde realiu laiku (panaudojant GeForce GTX1080Ti grafinį procesorinį įrenginį).Newest visual object tracking algorithms are getting better every year but only a small fraction of them can work at real time. The goal of this work was to increase a speed of object tracking algorithm. Pedestrians were used as an example. All tasks were accomplished - a group of methods were proposed to enable pedestrian tracking on real time (using GeForce GTX1080Ti GPU). Master Thesis consists of 61 pages without annexes, 25 figures, 7 tables, 37 bibl. entries, 2 annexe
The influence of intake valve timing on the environmental performance of the SI engine using gasoline and natural gas
No full textThe tightening of environmental requirements has forced car manufacturers to look for various ways to reduce exhaust gas emissions. The existing structural solutions of internal combustion engines allow this type of pollution to be reduced by adjusting the intake valve timing. This is especially relevant when it comes to reducing spark ignition engine emissions when using natural gas as fuel. In this study, a wide range of intake valve timing adjustments from 24° to 54° every six crank angle degrees was taken at a constant engine speed (n = 2500 rpm) and different loads and fixed excess air ratios (λ = 1). The changes in oxygen (O2), carbon monoxide (CO), carbon dioxide (CO2), nitrous oxide (NOx), methane (CH4), and propane (C3H8) gas emissions were observed in the aforementioned intake valve timing range
Kvantinio taško ir fotosensibilizatoriaus-chlorino e6 komplekso stabilumo tyrimai ląstelių auginimo terpėse /
No full textMeasurement system for short-pulsed magnetic fields
No full textA measurement system based on the colossal magnetoresistance CMR-B-scalar sensor was developed for the measurement of short-duration high-amplitude magnetic fields. The system consists of a magnetic field sensor made from thin nanostructured manganite film with minimized memory effect, and a magnetic field recording module. The memory effect of the La1−xSrx(Mn1−yCoy)zO3 manganite films doped with different amounts of Co and Mn was investigated by measuring the magnetoresistance (MR) and resistance relaxation in pulsed magnetic fields up to 20 T in the temperature range of 80–365 K. It was found that for low-temperature applications, films doped with Co (LSMCO) are preferable due to the minimized magnetic memory effect at these temperatures, compared with LSMO films without Co. For applications at temperatures higher than room temperature, nanostructured manganite LSMO films with increased Mn content above the stoichiometric level have to be used. These films do not exhibit magnetic memory effects and have higher MR values. To avoid parasitic signal due to electromotive forces appearing in the transmission line of the sensor during measurement of short-pulsed magnetic fields, a bipolar-pulsed voltage supply for the sensor was used. For signal recording, a measurement module consisting of a pulsed voltage generator with a frequency up to 12.5 MHz, a 16-bit ADC with a sampling rate of 25 MHz, and a microprocessor was proposed. The circuit of the measurement module was shielded against low- and high-frequency electromagnetic noise, and the recorded signal was transmitted to a personal computer using a fiber optic link. The system was tested using magnetic field generators, generating magnetic fields with pulse durations ranging from 3 to 20 μs. The developed magnetic field measurement system can be used for the measurement of high-pulsed magnetic fields with pulse durations in the order of microseconds in different fields of science and industry.iss. 3vol. 2
Classification of muscle activity patterns in healthy children using biclustering algorithm
No full textIn recent years, there has been major interest in recognising electromyography (EMG) patterns. This work proposes a new method based on a biclustering algorithm which can group strides showing homogeneous EMG activation intervals. The surface EMG signals of biceps femoris, rectus femoris, semitendinosus, lateral gastrocnemius, and medial gastrocnemius muscles of 17 healthy children aged between 4 and 11 years old were obtained using a Trigno EMG wireless system. The data set was tested for different values of parameter α (the threshold describing when the multiple node deletion step is used) and δ (the threshold that limits the value of the mean square residue). The highest number of coincidences of muscle activation was observed in 6 to 7-year-old subjects. This was not affected by their anthropometrics or gender. The obtained biclusters reflect actual differences between the subjects’ gait parameters, namely stride length, stride time, and walking speed. These results can be used to develop strategies for finding homogeneous groups of patients.vol. 8
Antibiotic resistance in patients with liver cirrhosis: Prevalence and current approach to tackle.
No full textRegardless of etiology, complications with bacterial infection in patients with cirrhosis are reported in the range of 25%-46% according to the most recent data. Due to frequent episodes of bacterial infection and repetitive antibiotic treatment, most often with broad-spectrum gram negative coverage, patients with cirrhosis are at increased risk of encountering multidrug resistant bacteria, and this raises concern. In such patients, extended-spectrum beta-lactamase and AmpC-producing Enterobacterales, methicillin- or vancomycin-resistant Staphylococcus aureus, vancomycin-resistant Enterococci, carbapenem-resistant Pseudomonas aeruginosa, and Acinetobacter baumannii, all of which are difficult to treat, are the most common. That is why novel approaches to the prophylaxis and treatment of bacterial infections to avoid antibiotic resistance have recently been developed. At the same time, our knowledge of resistance mechanisms is constantly updated. This review summarizes the current situation regarding the burden of antibiotic resistance, including the prevalence and mechanisms of intrinsic and acquired resistance in bacterial species that most frequently cause complications in patients with liver cirrhosis and recent developments on how to deal with multidrug resistant bacteria.iss. 31vol. 1
Individual Orthopedic Insoles Automated 3D Modeling and Production System Design
No full textBaigiamajame magistro darbe nagrinėjamos individualių ortopedinių vidpadžių gamybos problemos ir sprendimai taikant kompiuterizuotas sistemas. Apžvelgta mokslinė literatūra, kurioje aprašyti atlikti eksperimentiniai ir teoriniai darbai. Pateikti pėdos formos ir parametrų matavimų sprendimai. Išvardytos ir palygintos automatizuotos gamybos sistemos. Suprojektuota automatizuota vidpadžių 3D modeliavimo sistema, kurią sudaro 3 pagrindiniai procesai: duomenų apdorojimas, automatinis 3D modelio kūrimas ir pabaigto gaminio medžiagų atsparumo tikrinimas. Sukurta 3D modeliavimo sistema yra palyginama su panašiomis rinkoje esančiomis programomis. Darbo pabaigoje yra pateikiamos baigiamojo darbo išvados ir siūlymai. Darbą sudaro 5 dalys: įvadas, ortopedinių vidpadžių 3D modeliavimo ir gamybos analizė, automatizuotos 3D modeliavimo sistemos projektavimas, išvados ir siūlymai, literatūros sąrašas. Darbo apimtis – 60 p. teksto be priedų, 37 iliustr., 12 lent., 53 bibliografiniai šaltiniai. Atskirai pridedami darbo priedai.In this final master thesis the problems and solutions of individual orthopedic insoles production using computerized systems is analyzed. Experimental and theoretical works in scientific literature is described. Foot shape and parameters measurements solutions are performed. Automated production systems are compared. Automated orthopedic insoles 3D modelling system is designed, which consists of 3 parts: data processing, automated creation of 3D model and finished product material simulation trial. Comparison of designed 3D modelling system and other similar programs are performed. Thesis conclusions and suggestions are presented. Structure: introduction, 3 parts of the text, conclusions and suggestions, references. Thesis consist of: 60 p. text without appendixes, 37 pictures, 12 tables, 53 bibliographical entries. Appendixes included
Study on gas flow parameters and fractional removal efficiency of ultrafine particulate matter in newly developed electro cyclone-filter
No full textThe treatment of polluted industrial flow remains a relevant topic for the purpose of sustainable development and improvement of the general state of the environment. The removal of particulate matter, and especially their fine and ultra-fine fractions, from the gas flow, is an urgent task, but it poses many challenges and demands for purification technology. This paper presents the results of the first stage of the research using a newly developed cleaning device operating by a complex principle, which consists of a new generation two-stage centrifugal filtration device and an electro-filter. The rate of air flow was varied from 0.3 to 1.16 m/s at the inlet and corresponds to an air flow yield of 53 m3/h to 205 m3/h. The maximum pressure drop at an air flow of 255 m3/h is 26 Pa. Research has shown that the efficiency of removing ultra-fine particulate matter is up to 99.7% for particles 0.3–0.5 µm in size at 200 m3/h of the air flow rate.iss. 3vol. 1
Theoretical research of the processes to reduce the concentration of chlorinated compounds with natural fibers
No full textDisinfectants based on chlorine are the most commonly applied biocides for public spaces disinfection. Various studies show the use of sodium hypochlorite went up several times during the pandemic. Chlorinated compounds after they enter stormwater react with organic, inorganic and anthropogenic pollutants there and form harmful disinfection by-products. The article aims to present theoretical research of the processes linked to reduce the chlorinated compounds concentrations in stormwater. Research theory is based on the scientific information and the experiments’ results. The equations of mass transfers are used to describe the process. Analysis is focused on the case when chlorinated compounds concentrations in stormwater change depending on mass transfer from solution to filter fiber. Experiments present that after filtration with natural fibers the amount of disinfectants in stormwater decreased approximately 60 percent. The values of mass transfer reveal the efficiency of hemp and peat fibers to transport chlorinated compounds (C22H48ClN). Research found out the values of different filter materials are quite similar: 0.20 Def.·106, cm2s–1 (hemp) and 0.19 Def.·106, cm2s–1 (peat).Taip / Ye
Improvement and Optimization of Manufacturing Processes in Metal Processing Companies
No full textŠiame baigiamajame magistro darbe yra nagrinėjama gamybos proceso tobulinimo ir optimizavimo galimybės metalo apdirbimo pramonės įmonėse. Apžvelgiama metalo apdirbimo pramonė Lietuvoje, pagrindiniai privalumai ir trūkumai siekiant pastovaus tobulinimo ir optimizavimo. Ištirta, kaip Lietuvos metalo apdirbimo įmonės tobulina savo gamybos sistemą, koks yra gamybos sistemos tobulinimo ryšys tarp skirtingo dydžio įmonių. Darbe yra pateikiami apklaustų įmonių, susijusių su metalo apdirbimo darbais, tyrimo rezultatai. Nustatyti pagrindiniai veiksniai, turintys įtakos metalo apdirbimo įmonių gamybos proceso tobulinimui ir optimizavimui, taip pat didžiausios ir dažniausiai pasitaikančios problemos gamyboje. Remiantis tyrimo rezultatais yra pateikiamas gamybos proceso tobulinimo ir optimizavimo modelis vidutinio dydžio įmonėms metalo apdirbimo sektoriuje bei pateikiamos išvados ir pasiūlymai kaip tobulinti ir optimizuoti gamybos valdymą. Darbą sudaro: įvadas, metalo apdirbimo įmonių teorinių teiginių analizė, metalo apdirbimo įmonių probleminiai sričių empiriniai tyrimai, gamybos proceso tobulinimo ir optimizavimo modelis, siūlymai ir išvados. Darbo apimtis – 78 p. teksto, be priedų, 66 iliustr., 1 lent., 38 bibliografiniai šaltiniai. Atskirai pridedami darbo priedai.This final master's thesis examines the possibilities of improvement and optimization of the production process in metal processing industry companies. An overview of the metalworking industry in Lithuania, the main advantages and disadvantages of constant improvement and optimization. It has been investigated how Lithuanian metal processing companies improve their production system, what is the link between the development of the production system and companies of different sizes. The paper presents the results of the survey of companies involved in metalworking work. The main factors that influence the improvement and optimization of the manufacturing process of metal processing companies as well as the biggest and most common problems in production have been identified. Based on the results of the research, a model for improvement and optimization of the production process for medium-sized companies in the metalworking sector is presented and conclusions and suggestions are provided on how to improve and optimize production management. Structure: introduction, analysis of theoretical statements of metal processing companies, problematic empirical research of metal processing companies, model of production process improvement and optimization, suggestions and conclusions. Thesis consist of: 78 p. text, without appendixes, 66 pictures, 1 table, 38 bibliographical entries. Supplements are included separately