The paper presents the efficiency of the application of thermovision testing in the process of detecting potential spots of protection in the regular and preventive maintenance of power plants. The ...above examples of tests were made in 2016 and 2017 in substations under the jurisdiction of Elektroprenos BiH, which are covered by the Visegrad field unit during the maintenance process. Termovision testing is an integral part of regular testing throughout the year to identify potential breakdown sites that will be repaired and repaired on time. Using this approach, the efficiency and availability of the supervised system has been increased, with potential failures observed during maintenance not occurring in the upcoming period, which shows that this method is very effective in the case of early removing potential "critical" points in the plant. Infrared cameras were used to control, control, and diagnose the condition of the elements in the power plants: FLIR ThermaCAM PM 675 and the Fluke Ti400 9Hz Thermal Imager model. Test results are presented in this paper.
U radu je dat primer primene jedne vrste niskofrekventnog filtriranja sa usrednjavanjem, koje se primenjuje u sistemima za detekciju i praćenje ciljeva u vazdušnom prostoru primenom termovizije. Date ...su dve metode filtriranja slike. Prva metoda koristi niskofrekventno konvoluciono filtriranje a druga usrednjavajući filtar na osnovu srednje vrednosti nivoa sivog. Ovi filtri su primenjeni u sistemima za praćenje uz pomoć infracrvenih senzora. Određivanje nivoa praga filtriranja vrši se uz pomoć statističkih osobina slike. Veoma važan korak u procesu praćenja je određivanje prozora praćenja, koji maze biti, po dimenzijama, fiksan ili adaptibilan. Pogrešna procena o postojanju cilja u prozoru može se doneti u slučaju prisustva šuma pozadine, predpojačavača, detektora, itd. Filtriranje je neophodan korak u ovim sistemima, kao značajan činilac U povećanju brzine i tačnosti praćenja. / A case of image filtering in air target detecting and tracking systems is described in this paper. Two image filtering methods are given. The first method is performed using a low pass convolving filter and the second one uses the mean value of gray level filter. The main goal of the cited filtering is implementation in IR (infra red) systems. Some statistical features of the images were used for selecting the threshold level. The next step in the algorithm is the determination of a 'tracking window' that can be fixed or adaptive in size. A false estimation of a target existing in the window may be influenced by the background noise, low noise amplifier detector, etc.
Building materials come into the focus of interest at the time when waste,
industrial or municipal, is becoming increasingly important as a potential
raw material. Probable cause for that is the base ...of building materials-
cement which contains numerous waste materials originating from the
ingredients or the fuel used for its production. On the one side, the primary
application area of building materials has been constantly expanding, but
beside these materials, the alternative materials are also taking their
place. Modification of conventional building materials is commonly realized
using some of the secondary raw materials from various industrial processes.
Generally, building materials and their products are important recipients of
waste as long as they can provide complete immobilization without degradation
of their basic properties. Nowadays, most researches in the world are devoted
to using ashes from power plants and other large incinerators in order to
obtain high-quality building material with wide range of applications. By
following the similar concept, possibility of using secondary sulfur as an
alternative component of concrete was analized in this thesis. Waste sulfur
is often neglected despite the large amount of globally produced secondary
sulfur which possibly exceeds the amount of ash to whom a great importance is
given. Technological revolution has brought a reversible process to the
natural process of sulfur removing from the atmosphere, that is sulfur
restoring by processing of crude oil, natural gas and ores. The by-products
thereby obtained, sulfur and sulfuric acid, present serious environmental
problem. Therefore, it was necessary to consider alternative ways of sulfur
and sulfuric acid valorization in the real process (large scale). In this
case, the solutions can be found in application of these types of secondary
sulfur for fertilizers production, immobilization of waste materials by
conversion into insoluble compounds, and as an additive in building
materials. In the research presented in this thesis, the use of secondary
sulfur as binding agent in concrete for wide application possibilities was
analysed. The starting point was the fact that sulfur is known as a binder
and that it can quite possibly be used as a binding agent in building
materials. The initial studies were directed towards modification of sulfur
for the application in sulfur concrete. The next step was the analysis of
technology ie. process of sulfur concrete obtaining in order to optimize the
technological parameters for producing high-quality material. This was
followed by the researches related to the examination of sulfur concrete
properties, as well as testing the new material quality during the
exploitation, which was more important. The fact is that the influence of
various environmental factors causes a certain degree of destruction and
therefore degradation of the basic properties of all materials, including the
building materials. In case of metals, these processes are well-known as
corrosion which can be generally attributed to all inorganic materials. In
case of organic materials, the mentioned process is known as material aging
under the influence of environmental factors. The other fact is that the
processes of accellerated corrosion or aging are caused by high atmospheric,
water, and soil pollution, so the investigation of the newly obtained
material- sulfur concrete was directed towards the analysis of its behavior
in the presence of the induced destruction agent. There are two key elements
during the application of this methodology. The first one is a selection of
the induced destruction gent, while the other one is a selection of methods,
that means methodologies for monitoring and quantifying changes that occur
under the influence of the certain agent. When choosing the induced
destruction agent for inorganic materials, the decisive factor can be
aggressiveness of the substance, whereby strong acids or bases are usually
selected. In the scope of this research, hydrochloric acid, sulfuric acid,
and sodium chloride were used in screening experiment which was realized with
the aim to choose the induced destruction agent. In the second screening
experiment, which was performed using chosen induced destruction agent-
hydrochloric acid, the time required for the complete degradation of the
reference material, Portland cement concrete was investigated. The results
showed that the reference material lost its properties after 21 days of
treatment, while sulfur concrete kept its properties even after a year of
treatment. The filler and the treatment time were also determined through
screening experiments. In this way, after screening experiments, the
material, the induced destruction agent, and the treatment time were
precisely defined. In examining the materials properties, as well as in
selecting methods for quantifying their changes, classical aspect was not
applied. The idea was to implement a number of destructive and nondestructive
methods and correlate the material properties with the structure. The
structure of the obtained material was analyzed by the methodology of
quantification of visual information whereby the images obtained by optical
and scanning electron microscopes were used. It means that properties of the
material structure were analyzed by different resolutions. For testing the
material behavior under the influence of the induced destruction agent, the
ultrasonic method, which offers defining the homogenity changes of the
samples during the treatment time, and thermovision for examining the thermal
properties were applied. Mechanical testing results showed that sulfur
concrete had possessed satisfactory properties and kept them after six months
of treatment by the induced destruction agent. Based on the ultrasonic
examination, it was found that significant qualitative changes in the
structure of sulfur concrete occurred after a certain period, whereby the
most intensive homogenity change happened during 21 days of the agent
influence, and after that period, its effect weakened. This indicated the
rearrangement of the constituents in the material. Scanning electron
microscopy showed a rearrangement of the structure during the treatment.
Energy dispersive X-ray analysis (EDS) was also performed. The mapping showed
the concentration of sulfur in some locations. Based on the SEM analysis, it
was concluded that sulfur had a major role in rearrangement that was
occurring as a consequence of the agent influence. The thermovision analysis
results pointed out significant structural differences among the sulfur
concrete samples treated by the agent during the different time periods.
Also, the same analysis showed noticeable differences in thermal properties
between sulfur concrete and Portland cement concrete samples owing to the
structural changes during the exposure to the agent. Based on the obtained
results, working models for defining correlations between mechanical and
structural properties of the tested materials were developed. As an additon
to the study of possible secondary sulfur application in production of
building materials, synthesis of sulfur modified asphalt and its
characterization by standard methods were presented. The tests showed
advantages of sulfur modified asphalt over the conventional asphalt. Part of
these results was published in relevant international journals.
Građevinski materijali dolaze u fokus interesovanja u vreme kada otpad, bilo
industrijski, bilo komunalni, dobija na značaju kao potencijalna sirovina.
Verovatan razlog za to je osnova građevinskog materijala-cement, koji u svom
sastavu ima i veliki broj uslovno otpadnih materijala koji mogu da vode
poreklo od sastojaka ili od energenata koji se koriste za njegovu
proizvodnju. S jedne strane, primarna primena građevinskih materijala sve se
više širi, ali pored njih i alternativni materijali dobijaju svoje mesto.
Modifikacija konvencionalnih građevinskih materijala uglavnom se vrši
korišćenjem nekih od sekundarnih sirovina iz različitih industrijskih
procesa. Generalno gledajući, građevinski materijali i njihovi proizvodi
značajni su akceptori otpadnih materija ukoliko mogu u potpunosti da izvrše
njihovu imobilizaciju, pri čemu mora biti ispunjen uslov da ne dolazi do
degradacije osnovnih svojstava samog materijala. Danas se najveći broj
istraživanja u svetu odnosi na korišćenje pepela iz termoelektrana i ostalih
velikih insineratora u cilju dobijanja kvalitetnog građevinskog materijala
široke primene. Prateći sličnu koncepciju, u ovom radu prikazana je i
analizirana mogućnost korišćenja sekundarnog sumpora kao alternativnog
sastojka betona. Sumpor cesto predstavlja zapostavljen otpad, iako je veliko
pitanje da li količina proizvedenog sekundarnog sumpora na svetskom nivou
premašuje količinu pepela kome se pridaje veliki značaj. Zahvaljujući
tehnološkoj revoluciji, došlo je do vraćanja sumpora u atmosferu preradom
nafte, prirodnog gasa i II ruda, što predstavlja reverzibilan proces
prirodnom uklanjanju sumpora iz atmosfere. Tako se kao nusproizvodi dobijaju
sumpor i sumporna kiselina koji danas predstavljaju ozbiljan ekološki
problem. Zbog toga je bilo neophodno razmatrati alternativne načine
valorizacije sumpora i sumporne kiseline u realnom procesu (large scale). U
tom slučaju, rešenja se mogu naći u korišćenju pomenutih vrsta sekundarnog
sumpora u proizvodnji đubriva, imobilizaciji otpadnih materijala prevođenjem
u nerastvorna jedinjenja i kao dodatak odgovarajućim građevinskim
materijalima. U prikazanim istraživanjima analiziran je aspekt korišćenja
sekundarnog sumpora kao veziva u betonima čije su mogućnosti primene široke.
Polazna osnova bila je činjenica da je sumpor poznat kao vezivna supstanca i
da ga je sasvim moguće koristiti kao vezivno sredstvo i u građevinskim
materijalima. Prva istraživanja bila su usmerena ka modifikaciji sumpora za
primenu u sumpornom betonu. Sledeći korak bio je analiza tehnol
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