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One of the quality requirements of thermal imaging devices used in surveillance systems and in forensics refers to the assessment of its capabilities in relation to remote detection, recognition and identification of far-off objects of interest. This paper discusses the concept of spatial frequency and compares the estimated values of the nominal static characteristics of the range based on the measurement of the characteristics of a thermal imaging camera according to standard methods (MRTD - Minimum Resolvable Tempera-ture Difference, MDTD - Minimum Detectable Temperature Difference, TOD - Triangle Orientation Discrimination) on an arbitrarily chosen thermal imaging camera.

The study aimed to determine the concentration of energy-related hormones in cow’s milk and to consider them from a public health perspective. Fourteen Holstein cows were subjected to milk and blood sampling on the following days in lactation (DIL): 10, 30, 60, 90, 150, 180, 210, 250 and 280 to determine milk hormones, fat and protein content and blood biochemical parameters. For the same purpose, bulk-tank milk was sampled and samples of retail m ilk with 1.5% (CM1.5) and 3.2% (CM3.2) fat was purchased. Milk insulin-like growth factor-1 (IGF-1) values were signifi cantly lower at 90, 150, 180, 210 and 250 and signifi cantly higher at 10, 30 and 60 DIL than lactation average (LA). Milk insulin concentrations were signifi cantly lower at 30, 60 and 90 and higher at 210, 250 and 280 DIL than LA. Free thyroxine (fT4) level in the milk was higher at 250 DIL, while milk free triiodothyronine (fT3) concentrations were lower at 30, 60, 90 and 280 DIL, and signifi cantly higher at 10 and 180 DIL than respective LA. Milk cortisol levels were lower at 60 and 280 DIL than LA. All measured milk hormones were signifi cantly lower in CM1.5 compared to CM3.2, bulk-tank milk and LA. An exception was the LA of IGF-1, which was signifi cantly lower than the IGF1 content in CM1.5. Blood biochemical parameters fl uctuated evenly during lactation and were within the reference range. Hormone concentrations in cow’s milk fl uctuate during lactation, giving milk an important role in the context of public health., Istraživanje je imalo za cilj određivanje koncentracije hormona u mleku krava u različitim fazama laktacije, mleku iz laktofriza i maloprodajnom mleku. Uzorci mleka i krvi prikupljeni su 10., 30., 60., 90., 150., 180., 210., 250. i 280 dana laktacije od četrnaest krava holštajn rase radi određivanja koncentracije hormona, masti i proteina u mleku i biohemijskih parametara krvi. U iste svrhe uzorkovano je mleko iz laktofriza i nabavljeno je komercijalno mleko sa 1,5% (CM1,5) i 3,2% (CM3,2) mlečne masti. Koncentracije insulinu-sličnog faktora rasta-1 (IGF-1) u mleku bile su značajno niže 90., 150., 180., 210. i 250. dana i značajno više 10., 30. i 60. dana laktacije poredeći sa laktacionim prosekom (LP). Insulin je imao značajno niže koncentracije u mleku 30., 60. i 90. dana i značajno više koncentracije 210., 250. i 280. dana laktacije poredeći sa LP. Koncentracija slobodnog tiroksina (fT4) je bila viša 250. dana, dok je nivo slobodnog trijodotironina (fT3) bio značajno niži 30., 60., 90. i 280. dana i značajno viši 10. i 180. dana u poređenju sa odgovarajućim LP. Nivo kortizola u mleku je bio niži 60. i 280. dana laktacije poredeći sa LP. Svi hormoni su imali značajno niže koncentracije u CM1,5 nego u CM3,2, mleku iz laktofriza i LP. Izuzetak je LP za IGF-1, koji je bio značajno niži nego nivo IGF-1 u CM1,5. Biohemijski parametri krvi su blago fl uktuirali tokom laktacije, ali su ostali u referentnom opsegu. Koncentracije hormona u kravljem mleku fl uktuiraju tokom laktacije, što daje značaj mleku u kontekstu javnog zdravlja.

Srednjevekovna crkva manastira Savinac, datovana u 13. vek, je predmet potencijalne obnove i konzervacije, kao kulturno dobro Srbije od velikog značaja. Predmet istraživanja – jednobrodna crkva sa kulom na ulazu je u veoma ruiniranomstanju, bez delova zidova i kompletne krovne konstrukcije. Rad ukazuje na mogućnosti kombinovanja dva tipa digitalnih podataka (prikupljenih na terenu tokom 2018. god), u procesu kvalitativne ocene stanja građevine, sa stanovišta nivoa oštećenosti, na osnovu podataka prikupljenih na terenu (tokom istraživanja u 2018. god.). To su podaci dobijeni metodama terestričkog laserskog skeniranja (TLS) i termovizijskog snimanja (delova zidova)

The paper presents the results of research into the possibility of using a mixture of various types of biodiesel fuel with standard diesel fuel of mineral origin in a mixture ratio of 50:50, labelled B50, on a diesel engine with direct injection intended for small agricultural machinery driving. The analysis was performed in terms of comparing the pressure flow in the cylinder and the dynamics of the combustion process over the heat release flow in the engine cylinder. It was found that with the specified fuel mixture ratio in the mixture there were no major changes in the pressure flow in the cylinder and the heat release process, which indicates that the given fuel mixture ratio can be used without problems to power this class of engine in long-termoperation, without fear of possible harmful consequences for the engine.

In the paperwork had been observed nessesery steps in the introduction of diesel engines final production application in the last ten to twenty years, it can be clearly concluded that their development is significantly dictated by the legal regulations on permitted exhaust emissions. In order to meet these regulations, successively with the introduction of increasingly stringent requirements, improvements were made to the engine and its systems in order to reduce the emission of toxic components below the prescribed limits, ie to meet them. The biggest problem was achieving the required emission levels of PM particles and nitrogen oxides NOx. This is all the more so because the requirements for reducing these components were very often contradictory, ie solutions that reduced particulate emissions most often increased the emission of nitrogen oxides.

Погонски системи савремених возила предмет су истраживања великог броја научника широм света. Основни циљ истраживања огледа се у задовољавању све сложенијих и оштријих законских одредби у погледу токсичне издувне емисије и смањења потрошње горива, уз задржавање повољних перформанси возила. Хибридни погонски системи који, поред мотора са унутрашњим сагоревањем, обухватају и додатну погонску машину и алтернативни акумулатор енергије, нуде велике могућности у погледу уштеде горива. Од пресудне важности за остваривање потенцијалних уштеда јесу оптимизација функционалних и управљачких параметара система. Предмет ове дисертације јесте експериментално и теоријско истраживање у области оптимизације хидрауличног хибридног погонског система намењеног погону возила јавног градског превоза путника. Важна одлика таквих система огледа се у употреби хидро-пнеуматских акумулатора које карактеришу ниске вредности специфичне енергије. Управо зато, јавља се потреба да се пажљивим избором параметара акумулатора омогући максимално прикупљање енергије кочења у фазама возног циклуса када ће и резултујуће уштеде у потрошњи бити највеће. Формирањем детаљног симулационог модела хидрауличног хибридног погонског система, извршено је одређивање утицаја масе еластомерне пене, притиска преднапрезања и радне запремине хидро-пнеуматског акумулатора на степен корисности погонског система у целини. Такође, испитана је могућност примене метода заснованих на неуронским мрежама у процесу извођења и примене оптималног управљачког алгоритма. На основу снимљених возних циклуса, формиран је оптималан алгоритам управљања употребом референтне методе динамичког програмирања који је потом употребљен као улазни скуп података за тренирање вештачких неуронских мрежа различитих конфигурација. Применом функционалне оптимизације и предложене методе управљања, постигнуто је смањење потрошње горива од 23,9% у смеру кретања 1 и 25,5% у смеру кретања 2 и степен оптималности управљачког алгоритма од 83,7% и 79,8%, респек, Great scientific and engineering effoorts are being invested in improving the fuel economy and emission performance standards of powertrain systems amid ever-increasing legislative pressure. Hybrid powertrain systems, comprising a conventional internal combustion engine and an additional prime mover and its corresponding energy storage system, offeffoer great opportunities for fuel economy improvements. However, functional and control parameters optimization is of crucial importance in order to achieve the full extent of potential improvements. The subject of this dissertation is experimental and theoretical investigation into the ficeld of optimization of a hydraulic hybrid powertrain system intended for the propulsion of a transit bus. TheTheese hybrid propulsion solutions employ hydro-pneumatic accumulators for energy storage, which are characterized by low specific energy values. Because of this, it is of crucial importance to carefully choose the accumulator parameters in order to harness the maximum amount of regenerative braking energy during the deceleration phases that will yield the greatest fuel economy improvement. A comprehensive simulation model of a hydraulic hybrid powertrain system has been devised, which has allowed for the determination of the influfluuence of elastomeric foam mass, preload pressure and accumulator capacity on the resulting powertrain system efficfficciency and the potential fuel savings. For maximizing the achievable fuel savings, a neural network-based control algorithm trained using the optimal control trajectories derived using Dynamic Programming has been investigated. By applying the functional and optimal control optimizations presented in this dissertation, average fuel savings of 23.9% have been achieved in direction 1 of the transit bus driving cycle and 25.5% in direction 2. TheTheese ficgures represent 83.7% and 79.8% of the fuel economy improvements obtained using the unimplementable Dynamic Programming algorithm, res

Cow milk is widely consumed by human children and adults due to its nutritional value. Besides nutrients, milk contains naturally occurring hormones, including insulin like growth factor-1 (IGF-1), that may alter their blood levels in the consumers. At the same time, the impact of IGF1 on human health is still unclear and controversial. The aim of the study was to determine IGF-1 concentrations in cow colostrum and milk and to discuss them from the aspect of human health. Twenty Holstein cows were enrolled in the study and subjected to colostrum, milk and venous blood sampling in order to determine the IGF-1 concentration by the radioimmunoassay (RIA). Colostrum was sampled at 2, 14 and 26 hours (1st, 2nd and 3rd colostrum) after calving, while milk and venous blood were taken 10 days after calving. The concentration of IGF-1 was the highest in the 1 st colostrum and decreased significantly with each subsequent sampling, so the lowest concentrations were detected in milk sampled 10 days after calving. High concentrations of IGF-1 observed in colostrum, especially in the 1st colostrum, reflect its potential for eventually use in the treatment of various intestinal diseases. However, further research should determine the conditions and limitations of its application. On the other hand, additional research is needed to determine whether IGF-1 in milk has harmful effects on human health and whether it is necessary to limit the permitted presence of this hormone in cow milk.

Temperature distribution induced by laser radiation is a very important parameter for an efficient and safe application of lasers in different ceramic processing techniques. This paper presents the results of an infrared thermography (IRT) application for monitoring temperature distribution on a ceramic surface during Nd: YAG laser irradiation with different fluences and 8ns pulse duration. FLIR, E40 and SC7200 IR cameras were used with the aim of recording the maximum temperature in the irradiated zones. It was expected that IRT could give some information related to the heat affected zone and possible damage to the base material; however, the results have shown that IR cameras, even those with high performance such as SC7200, cannot record the maximum temperature value at the moment of laser operation, but only the average temperature of the bulk sample material after laser pulses. The results of the numerical simulation have confirmed the value of the thermographic measurements. The microstructure and micromorphology of the ceramic surface before and after the laser treatment were analysed by optical and scanning electron microscopy as well as by examining the roughness of the irradiated and non- irradiated surfaces, while the micromechanical changes were analysed by comparing the micro-hardness of the irradiated and non-exposed surfaces.

In the paperwork had been observed nessesery steps in the introduction of diesel engines final production application in the last ten to twenty years, it can be clearly concluded that their development is significantly dictated by the legal regulations on permitted exhaust emissions. In order to meet these regulations, successively with the introduction of increasingly stringent requirements, improvements were made to the engine and its systems in order to reduce the emission of toxic components below the prescribed limits, ie to meet them. The biggest problem was achieving the required emission levels of PM particles and nitrogen oxides NOx. This is all the more so because the requirements for reducing these components were very often contradictory, ie solutions that reduced particulate emissions most often increased the emission of nitrogen oxides.

Pogonski sistemi savremenih vozila predmet su istraživanja velikog broja naučnika širom sveta. Osnovni cilj istraživanja ogleda se u zadovoljavanju sve složenijih i oštrijih zakonskih odredbi u pogledu toksične izduvne emisije i smanjenja potrošnje goriva, uz zadržavanje povoljnih performansi vozila. Hibridni pogonski sistemi koji, pored motora sa unutrašnjim sagorevanjem, obuhvataju i dodatnu pogonsku mašinu i alternativni akumulator energije, nude velike mogućnosti u pogledu uštede goriva. Od presudne važnosti za ostvarivanje potencijalnih ušteda jesu optimizacija funkcionalnih i upravljačkih parametara sistema. Predmet ove disertacije jeste eksperimentalno i teorijsko istraživanje u oblasti optimizacije hidrauličnog hibridnog pogonskog sistema namenjenog pogonu vozila javnog gradskog prevoza putnika. Važna odlika takvih sistema ogleda se u upotrebi hidro-pneumatskih akumulatora koje karakterišu niske vrednosti specifične energije. Upravo zato, javlja se potreba da se pažljivim izborom parametara akumulatora omogući maksimalno prikupljanje energije kočenja u fazama voznog ciklusa kada će i rezultujuće uštede u potrošnji biti najveće. Formiranjem detaljnog simulacionog modela hidrauličnog hibridnog pogonskog sistema, izvršeno je određivanje uticaja mase elastomerne pene, pritiska prednaprezanja i radne zapremine hidro-pneumatskog akumulatora na stepen korisnosti pogonskog sistema u celini. Takođe, ispitana je mogućnost primene metoda zasnovanih na neuronskim mrežama u procesu izvođenja i primene optimalnog upravljačkog algoritma. Na osnovu snimljenih voznih ciklusa, formiran je optimalan algoritam upravljanja upotrebom referentne metode dinamičkog programiranja koji je potom upotrebljen kao ulazni skup podataka za treniranje veštačkih neuronskih mreža različitih konfiguracija. Primenom funkcionalne optimizacije i predložene metode upravljanja, postignuto je smanjenje potrošnje goriva od 23,9% u smeru kretanja 1 i 25,5% u smeru kretanja 2 i stepen optimalnosti uprav, Great scientific and engineering effoorts are being invested in improving the fuel economy and emission performance standards of powertrain systems amid ever-increasing legislative pressure. Hybrid powertrain systems, comprising a conventional internal combustion engine and an additional prime mover and its corresponding energy storage system, offeffoer great opportunities for fuel economy improvements. However, functional and control parameters optimization is of crucial importance in order to achieve the full extent of potential improvements. The subject of this dissertation is experimental and theoretical investigation into the ficeld of optimization of a hydraulic hybrid powertrain system intended for the propulsion of a transit bus. TheTheese hybrid propulsion solutions employ hydro-pneumatic accumulators for energy storage, which are characterized by low specific energy values. Because of this, it is of crucial importance to carefully choose the accumulator parameters in order to harness the maximum amount of regenerative braking energy during the deceleration phases that will yield the greatest fuel economy improvement. A comprehensive simulation model of a hydraulic hybrid powertrain system has been devised, which has allowed for the determination of the influfluuence of elastomeric foam mass, preload pressure and accumulator capacity on the resulting powertrain system efficfficciency and the potential fuel savings. For maximizing the achievable fuel savings, a neural network-based control algorithm trained using the optimal control trajectories derived using Dynamic Programming has been investigated. By applying the functional and optimal control optimizations presented in this dissertation, average fuel savings of 23.9% have been achieved in direction 1 of the transit bus driving cycle and 25.5% in direction 2. TheTheese ficgures represent 83.7% and 79.8% of the fuel economy improvements obtained using the unimplementable Dynamic Programming algorithm, res

Alternative propulsion fuels for diesel engines were highlights for a variety of research activities within a large number of R&D labs in the world. Curiosity, as well as basic interest in alternative fuel has been immense because of its reproducibility, renewability, as well as good ecological characteristics. Another reason for this interest is a favorable impact on the economies of the countries engaged in their production, by processing that kind of bio fuel. This paper presents the results of testing and research of the three types of alternative fuel gained from bio oil. Analyses and comparison of the dynamics of combustion process of these alternative fuels were done in relation to the reference diesel fuel. Burning process of methyl esters rapeseed (RME100), soya oil (SME100), waste cooking palm oil (PME100), as well as of regular euro diesel fuel were investigated. It was found that these fuels were highly usable in diesel engines if they had been produced according to a proper standard procedure under standard EN 14214. The application of bio fuel is also very interesting for the propulsion of agricultural engines and machinery, because it enables the individual farming of bio fuel products necessary for the appropriate own machinery.

Alternative propulsion fuels for diesel engines were highlights for a variety of research activities within a large number of R&D labs in the world. Curiosity, as well as basic interest in alternative fuel has been immense because of its reproducibility, renewability, as well as good ecological characteristics. Another reason for this interest is a favorable impact on the economies of the countries engaged in their production, by processing that kind of bio fuel. This paper presents the results of testing and research of the three types of alternative fuel gained from bio oil. Analyses and comparison of the dynamics of combustion process of these alternative fuels were done in relation to the reference diesel fuel. Burning process of methyl esters rapeseed (RME100), soya oil (SME100), waste cooking palm oil (PME100), as well as of regular euro diesel fuel were investigated. It was found that these fuels were highly usable in diesel engines if they had been produced according to a proper standard procedure under standard EN 14214. The application of bio fuel is also very interesting for the propulsion of agricultural engines and machinery, because it enables the individual farming of bio fuel products necessary for the appropriate own machinery.

Interesovanje za alternativna goriva koja bi se koristila za pogon motora sus je veoma veliko u čitavom svetu. Zato se istraživanja vezana za ovu problematiku vrše u mnogim vodećim svetskim laboratorijama za motore. Razlog ovog interesovanja su dostupnost ovakvih goriva, povoljne ekološke karakteristike i pozitivan uticaj na ekonomije zemalja koje ovakva goriva mogu da proizvode. U predmetnom radu se daje deo rezulta veoma kompleksnih i dugotrajnih istraživanja dinamike procesa sagorevanja kod dizel motora pogonjenog metilestrima biljnih ulja i to otpadnog palminog jestivog ulja, sojinog ulja i ulja uljane repice. Poređenje promena u radnom procesu motora, pre svega procesu sagorevanja, je vršeno pri sinhronizovanom radu motora na uobičajenim standardnim dizel gorivom mineralnog porekla. Analizom zakona (toka) sagorevanja svakog pojedinačnog goriva, utvrđeno je da postoje razlike koje nisu velikog karaktera, iz čega se može zaključiti da su goriva proizvedena iz biljnih ulja, a po važećem standardu, veoma kvalitetna goriva za pogon dizel motora. Ovo daje mogućnost naročito poljoprivrednim gazdinstvima da samostalno proizvode deo potrebnog goriva sa sopstvenih zemljišnih parcela uz uslov da poseduju odgovarajuću opremu za proizvodnju biodizela., Alternative propulsion fuels for diesel engines were highlights for a variety of research activities within a large number of R&D labs in the world. Curiosity, as well as basic interest in alternative fuel has been immense because of its reproducibility, renewability, as well as good ecological characteristics. Another reason for this interest is a favorable impact on the economies of the countries engaged in their production, by processing that kind of bio fuel. This paper presents the results of testing and research of the three types of alternative fuel gained from bio oil. Analyses and comparison of the dynamics of combustion process of these alternative fuels were done in relation to the reference diesel fuel. Burning process of methyl esters rapeseed (RME100), soya oil (SME100), waste cooking palm oil (PME100), as well as of regular Euro diesel fuel were investigated. It was found that these fuels were highly usable in diesel engines if they had been produced according to a proper standard procedure under standard EN 14214. The application of bio fuel is also very interesting for the propulsion of agricultural engines and machinery, because it enables the individual farming of bio fuel products necessary for the appropriate own machinery.

In contemporary transport sector and especially in the agricultural production, there is a large possibility of using alternative engine fuels. In the case of agricultural applications, the largest number of agricultural machinery's propulsion engines is diesel, which allows the use of various vegetable oils as propellants. However, this implies that these vegetable oils have been treated by appropriate esterification procedures and adapted for smooth use in engines. Such fuels are generally called biodiesel as well. This paper will present some results of an investigation of the combustion process of rapeseed methyl ester of a single-cylinder direct injection diesel engine designed to drive smaller agricultural machinery, thus engines. The results of the research are presented in the variant of the charged engine, whereby the charging process was performed by an external energy source (electromotor and Roots compressor) under laboratory conditions.

The paper presents the results of the study of the effect of different biodiesel-type fuels produced from the oils of several oilseeds on the exhaust gas composition of a direct injection diesel engine designed to drive smaller agricultural machinery. The fuels obtained in this way are derived from the corresponding oils by the method of esterification using methyl alcohol and a catalyst to give the corresponding methyl esters. The physicochemical characteristics of these methyl esters are approximately equal to the standard Euro diesel diesel fuel. During the research, a comparative measurement of the exhaust gas composition was made, at the propulsion of the engine with these fuels, followed by an appropriate analysis of the results. A suitable research installation has been formed to conduct these studies at the Institute of Motors, Faculty of Mechanical Engineering in Belgrade.

The paper presents the applied methods of testing, observations, problems and experiences gained during the development of a domestic high pressure pump at the Military Technical Institute, which can be of interest and benefit to the wider professional public. The pumps are intended and specially designed for diesel engines, with the nominal power of up to 1000 hp, and are produced in many varieties, in our country and abroad, in large number. The development of this pump proved to be very important, as the foreign business partner cancelled the contracted cooperation in the production and delivery of serial engines high-pressure pumps. Problems got even more complicated when the domestic manufacturer, after the ownership transformation, gave up the further cooperation on the almost agreed production of the domestic pump. In the last five years, efforts have been made to enable a domestic manufacturer to produce the pumps. Although it is a company that has never previously dealt with the development and production of such mechanical and hydraulic systems, the achieved results in production and the experience gained so far give real hope that the mutual efforts will reach the required quality and create a competitive product.