Wyniki wyszukiwania - BazTech

1

Wielkie oko – nowe okno na Wszechświat

Janiec Jakub

Postępy Fizyki

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2022

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T. 73, z. 1

7--10

PL

W momencie pisania tego tekstu świat z niecierpliwością spoglądał w niebo zastanawiając się, czy aby na pewno się uda? Lata opóźnień, problemy techniczne, nawet rozłożenie i ponowne złożenie całego urządzenia, aby upewnić się, że wszystko jest na miejscu i działa tak jak powinno. Kosmiczny teleskop im. Jamesa Webba przysporzył nam wiele problemów, nerwów oraz odpowiedzialny jest za niejeden siwy włos. W końcu nadszedł ten wielki dzień 25.12.2021

EN

At the moment of writing this article, the world was looking up nervously asking itself Will it’ll be all right?. Years of delay, technical issues. Even disassembly and assembly again and all this to make sure that everything will work as it should. James Webb Space Telescope is responsible for many sleepless nights and gray hairs. Yet, here we are, the big Day 25 December 2021.

2

Performance optimisation of the turning process along with multi-surface heating process

Sathish Kumar D., Thanigaivelan R., Natarajan N.

Materials Science Poland

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2022

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Vol. 40, No. 4

1--13

EN

Materials that are difficult to cut possess excellent qualities and machinability, though conventional machining techniques require additional energy to circumvent the problems associated with the turning process. In this study, heat-assisted turning of duplex stainless steel (SS) was carried out. Various heating techniques such as infrared (IR)-, ultraviolet (UV)- and hot air(HA)-assisted heating were adopted. The experiment used an L16 orthogonal array with the most significant parameters such as heating method, feed rate in millimetres per revolution (mm/rev), depth of cut (millimetres [mm]) and cutting speed (metres per minute [m/min])on the cutting force and surface roughness. The technique for order performance by similarity to ideal solution (TOPSIS) and grey relational analysis (GRA), were used to optimise the output performance. The results of TOPSIS showed that the 16th experimental combination, i.e., the HA heating method, with feed rate = 0.175 mm/rev, depth of cut = 0.1 mm and cutting speed = 150 m/min, required a smaller cutting force and resulted in lower surface roughness. In case of the GRA method, the best output performance was observed for the 15th experimental combination, that is, the HA heating method, with feed rate = 0.15 mm/rev, depth of cut = 0.2 mm and cutting speed = 200 m/min. Compared to the non-heat-assisted turning process, the HA- and UV-assisted processes required 10.25% and 7.69% lesser cutting force, respectively, and the surface roughness in case of the HA method was 15.13% lesser.

3

Detection, Identification, and Quantification of SF6 Point-Source Emissions Using Hyper-Cam LW Airborne Platform

Kastek Mariusz, Firmanty Krzysztof, Saute Benjamin, Gagnon Jean-Philippe, Lariviere-Bastien Martin, Pawelski Daniel

Pomiary Automatyka Robotyka

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2021

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R. 25, nr 3

37--41

EN

Detection, identification, and quantification of greenhouse gases is essential to ensure compliance with regulatory guidelines and mitigate damage associated with anthropogenic climate change. Passive infrared hyperspectral imaging technology is among the solutions that can detect, identify and quantify multiple greenhouse gases simultaneously. The Telops Hyper-Cam Airborne Platform is an established system for aerial thermal infrared hyperspectral measurements for gas survey applications. In support of the Hypercam, is developing a suite of hyperspectral imaging data processing algorithms that allow for gas detection, identification, and quantification in real-time. In the Fall of 2020, the Hyper-Cam-LW Airborne platform was flown above a validated SF6 gas release system to collect hyperspectral data for gas quantification analysis. This measurement campaign was performed to document performance of the Hyper-Cam gas quantification capabilities against known quantities of released gas.

PL

Wykrywanie, identyfikacja i kwantyfikacja gazów cieplarnianych jest niezbędna do zapewnienia zgodności z wytycznymi regulacyjnymi i złagodzenia szkód związanych z antropogenicznymi zmianami klimatu. Technologia pasywnego obrazowania hiperspektralnego w podczerwieni należy do rozwiązań, które mogą wykrywać, identyfikować i kwantyfikować wiele gazów cieplarnianych jednocześnie. Platforma lotnicza Telops Hyper-Cam jest uznanym systemem do lotniczych pomiarów hiperspektralnych w termicznej podczerwieni do zastosowań związanych z badaniem gazów. W ramach wsparcia dla Hypercam, opracowywany jest zestaw algorytmów przetwarzania danych obrazowania hiperspektralnego, które pozwalają na wykrywanie, identyfikację i kwantyfikację gazów w czasie rzeczywistym. Jesienią 2020 r. platforma Hyper-Cam-LW Airborne została umieszczona nad zatwierdzonym systemem uwalniania gazu SF6 w celu zebrania danych hiperspektralnych do analizy kwantyfikacji gazu. Ta kampania pomiarowa została przeprowadzona w celu udokumentowania wydajności możliwości kwantyfikacji gazu Hyper-Cam w odniesieniu do znanych ilości uwolnionego gazu.

4

Detection of ammonia leak in laboratory conditions using a FLIR 306 camera and a portable gas detector

Lisowska-Lis Agnieszka, Siudut Piotr

Science, Technology and Innovation

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2020

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Vol. 8, no. 1

35--41

EN

The study aimed to analyse detection methods of ammonia leakage by various electrical methods. Rapid detection of the escape of hazardous technical gases is extremely important in large chemical plants. The basis of the research was the use of a specialized camera, model FLIR GF306, to detect a leak of selected gases in a narrow infrared band. In laboratory conditions, the controlled emission of gaseous ammonia at various concentrations was simulated and gas detection was performed: a) using a narrow infrared thermography method, b) by a portable electrochemical detector dedicated to detecting ammonia. The turbulent flow of gas into the environment and high thermal contrast between the expanding gas and the background are the conditions for effective gas detection with a thermal imaging camera operating in a narrow infrared band.

5

Wykorzystanie badań termowizyjnych w przemyśle stalowniczym

Wittchen Wacław, Borecki Mariusz, Mazur Artur

Journal of Metallic Materials

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2020

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Vol. 72, no. 1

39--47

PL

Przedstawiono możliwości oraz wybrane przykłady praktycznego wykorzystania techniki termowizyjnej w przemyśle hutniczym jako bezinwazyjnej metody badawczej do pomiarów rozkładu temperatury na powierzchni badanego obiektu. Metoda ta może być wykorzystana we wszystkich etapach produkcji stali począwszy od przygotowania wsadu aż do gotowego wyrobu, jak również diagnostyki urządzeń technicznych. Podkreślono nieinwazyjny charakter badań, który nie zakłóca cyklu produkcyjnego.

EN

The paper presents the possibilities and selected examples of practical use of the thermal imaging technique in the metallurgical industry as a non-invasive testing method for measuring temperature distribution on the surface of the examined object. This method can be used in all stages of steel production, from charge preparation to finished product, as well as diagnostics of technical devices. The paper emphasises the non-invasive nature of the examination, which does not disturb the production cycle.

6

Electron-transfer complexation of morpholine donor molecule with some π – acceptors: Synthesis and spectroscopic characterizations

Al-Wasidi Asma S., Al-Jafshar Nawal M., Al-Anazi Amal M., Alosaimi Eid H., Refat Moamen S., El-Zayat Lamia, Al-Omar Mohamed A., Naglah Ahmed M., El-Nour K.M. Abou

Polish Journal of Chemical Technology

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2019

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Vol. 21, nr 4

82--88

EN

Morpholine is an interesting moiety that used widely in several organic syntheses. The intermolecular charge-transfer (CT) complexity associated between morpholine (Morp) donor with (monoiodobromide “IBr”, 2,3-dichloro-5,6-dicyano-1,4-benzoquinone “DDQ”, 2,6-dichloroquinone-4-chloroimide “DCQ” and 2,6-dibromoquinone-4-chloroimide “DBQ”) π–acceptors have been spectrophotometrically investigated in CHCl3 and/or MeOH solvents. The structures of the intermolecular charge-transfer (CT) were elucidated by spectroscopic methods like, infrared spectroscopy. Also, different analyses techniques such as UV-Vis and elemental analyses were performed to characterize the four morpholine [(Morp)(IBr)], [(Morp)(DDQ)], [(Morp)(DCQ)] and [(Morp)(DBQ)] CT-complexes which reveals that the stoichiometry of the reactions is 1:1. The modified Benesi-Hildebrand equation was utilized to determine the physical spectroscopic parameters such as association constant (K) and the molar extinction coefficient (ε).

7

MBE-grown MCT hetero- and nanostructures for IR and THz detectors

Dvoretsky S. A., Mikhailov N. N., Remesnik V. G., Sidorov Y. G., Shvets V. A., Ikusov D. G., Varavin V. S., Yakushev M. V., Gumenjuk-Sichevska J. V., Golenkov A. G., Lysiuk I. O., Tsybrii Z. F., Shevchik-Shekera A. V., Sizov F. F., Latyshev A. V., Aseev A. L.

Opto-Electronics Review

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2019

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Vol. 27, No. 3

282--290

EN

We present an overview of our technological achievements in the implementation of detector structures based on mercury cadmium telluride (MCT) heterostructures and nanostructures for IR and THz spectral ranges. We use a special MBE design set for the epitaxial layer growth on (013) GaAs substrates with ZnTe and CdTe buffer layers up to 3” in diameter with the precise ellipsometric monitoring in situ. The growth of MCT alloy heterostructures with the optimal composition distribution throughout the thickness allows the realization of different types of many-layered heterostructures and quantum wells to prepare the material for fabricating single- or dual-band IR and THz detectors. We also present the two-color broad-band bolometric detectors based on the epitaxial MCT layers that are sensitive in 150–300-GHz subterahertz and infrared ranges from 3 to 10μm, which operate at the ambient or liquid nitrogen temperatures as photoconductors, as well as the detectors based on planar HgTe quantum wells. The design and dimensions of THz detector antennas are optimized for reasonable detector sensitivity values. A special diffraction limited optical system for the detector testing was designed and manufactured. We represent here the THz images of objects hidden behind a plasterboard or foam plastic packaging, obtained at the radiation frequencies of 70, 140, and 275 GHz, respectively.

8

Concepts of infrared and terahertz photodetectors based on vertical graphene van der Waals and HgTe-CdHgTe heterostructures

Ryzhii Maxim, Otsuji Taiichi, Ryzhii Victor, Aleshkin Vladimir, Dubinov Alexander, Karasik V. E., Leiman V., Mitin V., Shur M. S.

Opto-Electronics Review

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2019

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Vol. 27, No. 2

219--223

EN

We review recently proposed concepts of infrared and terahertz photodetectors based on graphene van der Waals heterostructures and HgTe-CdHgTe quantum well heterostructures and demonstrate their potential.

9

Testing coatings of reflecting infrared radiation for a target for night shooting

Swiderski Waldemar, Hłosta Paweł, Polak Grzegorz, Tymiński Dariusz

Measurement Automation Monitoring

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2019

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Vol. 65, No. 2

41--43

EN

The paper presents the principle of operation of a new night-shooting target. Because this target requires a covering that reflects the infrared radiation flux generated by the reflector from its surface, testing of different variants of the cover and the shape of the target surface has been carried out. Emissivity is a physical parameter characterizing the radiant properties of real bodies. The emissivity coefficient of extruded aluminum sheet samples covered with a layer of green colored aluminum oxide was determined. The aluminum oxide layer was applied using two different technologies being galvanic and anodizing.

10

Real Time Thermal Imaging of Solid Oxide Fuel Cell

Jasiński M., Ziewiec K., Wojciechowska M.

Archives of Metallurgy and Materials

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2019

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Vol. 64, iss. 4

1207--1212

EN

In this work, a mid infrared thermography was used to study thermal behavior of solid oxide fuel cell (SOFC) with a circular shape and a diameter of 90 mm. The emissivity of the anodic surface of the fuel cell was determined to be from 0.95 to 0.46 in the temperature range 550-1200 K and the profile and temperature distribution of the anodic surface of the unloaded cell was given. The surface temperature of the cell was determined during operation and the polarity changes from open circuit voltage (OCV) to 0.0 V. It was found that the cell self-heating effect decreases with increasing temperature of the cell.

11

High-resolution thermal face dataset for face and expression recognition

Kowalski M., Grudzień A.

Metrology and Measurement Systems

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2018

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Vol. 25, nr 2

403--415

EN

Development of facial recognition or expression recognition algorithms requires input data to thoroughly test the performance of algorithms in various conditions. Researchers are developing various methods to face challenges like illumination, pose and expression changes, as well as facial disguises. In this paper, we propose and establish a dataset of thermal facial images, which contains a set of neutral images in various poses as well as a set of facial images with different posed expressions collected with a thermal infrared camera. Since the properties of face in the thermal domain strongly depend on time, in order to show the impact of aging, collection of the dataset has been repeated and a corresponding set of data is provided. The paper describes the measurement methodology and database structure. We present baseline results of processing using state-of-the-art facial descriptors combined with distance metrics for thermal face re-identification. Three selected local descriptors, a histogram of oriented gradients, local binary patterns and local derivative patterns are used for elementary assessment of the database. The dataset offers a wide range of capabilities - from thermal face recognition to thermal expression recognition.

12

Zastosowanie niskokosztowej matrycy czujników podczerwieni termicznej do detekcji osób

Zaraska K., Grzesiak W., Guzdek P., Kolaszczyński G., Piekarski J., Maćków P., Maj T., Polak A., Solnica D., Iwanicki P.

Elektronika : konstrukcje, technologie, zastosowania

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2018

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Vol. 59, nr 9

2--5

PL

W artykule przedstawiono zastosowanie niskokosztowej kamery podczerwieni termicznej o rozdzielczości 32x32 punkty do detekcji osób w pomieszczeniach dla zastosowania w systemach inteligentnego oświetlenia. Opisywane urządzenie złożone jest z kamery podczerwieni oraz mikrokontrolera realizującego algorytm obróbki obrazu w czasie rzeczywistym. Artykuł przedstawia kroki algorytmiczne niezbędne do detekcji obecności osoby w pomieszczeniu, przy jednoczesnym ignorowaniu innych źródeł ciepła, takich jak grzejniki.

EN

This paper describes the application of a low-cost 32x32 pixel infrared camera for detection of people for application in smart lighting systems. The system is based on an infrared camera and a microcontroller implementing an image processing algorithm in real time. The developed detection method allows detection of people in enclosed spaces, at the same time ignoring other sources of heat, such as heaters.

13

Dynamic Traffic Control and Management System for Smart Cities

Abdul Mateen, Sabeen Sher, Amjad Rehman, Zahid Hanif, Akhtar Tooba, Ashraf Mahmood

Advances in Science and Technology. Research Journal

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2018

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Vol. 12, no 4

216--225

EN

The computational capabilities of computers enable a human being to control the vehicles and their traffic. Automatic traffic control system not only reduces the effort of human but also provides secure and accurate results. Here, the architecture of Agent-Based Autonomous Controller (ABAC) that manages vehicles at traffic signals intelligently was proposed. The proposed solution is followed by a vehicle counting by infrared (IR) sensor; providing solution for independent and mutual dependent signals for smooth traffic flow; emergency vehicles alert and priority over public vehicles through Radio Frequency Identification (RFID). Finally, the proposed research was tested through simulation that reveals the performance over the previous traffic control and management architectures.

14

Pasywna tarcza termiczna do prowadzenia szkoleń i strzelań w dzień i w nocy

Świderski W., Hłosta P., Polak P., Tymiński D.

Problemy Techniki Uzbrojenia

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2017

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R. 46, z. 143

7--16

PL

W artykule przedstawiono koncepcję tarczy termicznej. Tarcza ta zapewnia prowadzenie strzelań z użyciem celowników noktowizyjnych i termowizyjnych w warunkach nocnych i dziennych bez wymiany tarczy. Obraz tarczy w celownikach nocnych jest widoczny dzięki owietleniu jej przez reflektor podczerwieni. Tarcza jest tak skonstruowana, aby odbity od tarczy strumień promieniowania podczerwonego był skierowany do obiektywu celownika. W porównaniu z dotychczas stosowanymi rozwiązaniami nowa tarcza termiczna ma wiele zalet: jest natychmiast gotowa do działania po oświetleniu przez reflektor bez konieczności dugotrwałego podgrzewania, zużywa znacznie mniej energii i cechuje ją większa żywotność. Projekt jest obecnie na etapie badań prototypu tarczy.

EN

A concept of a thermal target is presented in the paper. The same target may be used for firings with night-vision and thermo-vision sights at day and night conditions. A picture of the target is visible for it is lit by an infrared spotlight. The design of the target makes the beam of reflected infrared radiation hit the optics of a sight. The new thermal target has many advantages comparing to existing solution: it is ready to operate straightforwardly after lighting by the spotlight, without any need for a long time preheating, the consumption of energy is significantly reduced, and its life cycle is increased. The project is currently in the phase of testing the target’s prototype.

15

Infrared signature suppression systems in modern military helicopters

Paszko M.

Prace Instytutu Lotnictwa

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2017

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Nr 3 (248)

63--83

EN

Helicopters play an important role in air-to-ground fire covering and the short-distance air-to-air fights, as well as the anti-tank missions and battlefield force transferring. The detection and survivability of helicopters on a battlefield significantly depends on their infrared emissions level, as well as the methods, equipment and systems used by potential enemy. The automatic detection systems, recognition and identification of flying objects use among other the thermo-detection methods, which rely on detecting the infrared radiation emitted by the tracked object. Furthermore, due to low-altitude and relatively low flight speed, today’s combat assets like missile weapons equipped with infrared guidance systems are one of the most important threats to the helicopters performing combat missions. Especially meaningful in a helicopter aviation is infrared emission by exhaust gases, egressed to the surroundings. Due to high temperature, exhaust gases are a major factor in detectability of a helicopter performing air combat operations. In order to increase the combat effectiveness and survivability of military helicopters, several different types of the infrared suppressor (IRS) have been developed. This paper reviews contemporary developments in this discipline, with particular examples of the infrared signature suppression systems.

PL

Śmigłowce odgrywają niezwykle istotną rolę w krótkodystansowych walkach powietrznych jak również jako wsparcie ogniowe na cele naziemne, szczególnie w trakcie operacji przeciw pojazdom opancerzonym. Wykrywalność oraz żywotność śmigłowców na polu walki istotnie zależy od poziomu emisji podczerwieni emitowanej z ich pokładu jak również od metod, urządzeń i systemów detekcji wykorzystywanych przez przeciwnika. Współczesne systemy wykrywania, rozpoznawania i identyfikacji obiektów latających wykorzystują szereg metod termolokacyjnych, które polegają na wykrywaniu promieniowania podczerwonego emitowanego przez śledzony obiekt. W śmigłowcowej technice lotniczej, szczególnie istotna jest emisja podczerwieni z gazów spalinowych odprowadzanych do otoczenia. Ze względu na ich wysoką temperaturę, gazy spalinowe stanowią główne źródło emisji podczerwieni przez śmigłowiec w locie co w połączeniu ze stosunkowo niską prędkością oraz wysokością wykonywanych manewrów, czyni śmigłowce łatwymi celami dla współczesnych rakiet wyposażonych w głowice samonaprowadzające się na podczerwień. W celu zwiększenia bezpieczeństwa, efektywności oraz żywotności śmigłowców wojskowych wykonujących lotne zadania bojowe, opracowany został szereg metod redukcji poziomu emisji promieniowania podczerwonego. W niniejszej pracy przedstawiono przegląd współczesnych osiągnięć w tej dziedzinie wraz z prezentacją systemów maskowania podczerwieni stosowanych we współczesnych śmigłowcach wojskowych.

16

Mid-wave infrared liquid crystal shutter for breathalyzer applications

Piecek W., Jaroszewicz L., Miszczyk E., Raszewski Z., Mrukiewicz M., Kula P., Jasek K., Perkowski P., Nowinowski-Kruszelnicki E., Zieliński J., Kędzierski J., Olifierczuk M., Chodorow U., Morawiak P., Mazur R., Kowiorski K., Harmata P., Herman J.

Opto-Electronics Review

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2017

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Vol. 25, No. 2

103--109

EN

There exists a problem with an in situ diagnostics of contamination of ethyl alcohol in a human being exhaled air. When ethyl alcohol in a mouth blowing (in a gaseous state) exists, the characteristic C-H stretch absorption bands in CH3 and CH2 functional groups in ethanol (CH3CH2OH) appear at a wave length of λ = 3.42 µm. To investigate the presence of ethyl alcohol in exhaled human air, the light beam of λ = 3.42 µm is passing through an air sample. If one alternately measures the intensity of the investigated beam and the reference, a percentage of ethanol in the air sample can be estimated using a sensitive nondispersive infrared (NDIR) system with a stable operating flow mass detector. To eliminate a mechanical chopper and noise generating stepper motors, a photonic chopper as a liquid crystal shutter for λ = 3.42 µm has been designed. For this purpose, an innovative infrared nematic liquid crystal mixture was intentionally prepared. The working mixture was obtained by a selective removal of C-H bonds and its exchange by heavier polar substituents, what ensures a lack of absorption band of C-H bonds. The paper presents theory, concept and final experimental results of the infrared nematic liquid crystals mixture and the liquid crystal shutter for breathalyzer applications.

17

Work on developing a thermal shooting target

Swiderski W., Hłosta P., Polak G., Tymiński D.

Measurement Automation Monitoring

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2017

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Vol. 63, No. 4

158--161

EN

The paper presents work on the development of a thermal target providing for shooting with the use of night-vision and thermovision sights in night conditions as well as during the day, without changing the target. The image of the target in the night sight is visible by illuminating it through an IR lamp. The target is designed so that the reflected IR stream is directed towards the objective lens. Compared to existing solutions, the new thermal target has a number of advantages, such as it does not require long-time heating and is immediately ready to operate after thermal lamp lighting, significantly reducing energy consumption. The project is currently at the stage of prototype target testing.

18

Gas leaks detection using passive thermal infrared hyperspectral imaging

Lagueux P., Tremblay P., Morton V., Chamberland M., Farley V., Kastek M., Firmanty K.

Measurement Automation Monitoring

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2017

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Vol. 63, No. 2

65--68

EN

There are many types of natural gas fields including shale formations which are common especially in the St-Lawrence Valley (Canada). Since methane (CH4), the major component of shale gas, is odorless, colorless and highly flammable, in addition of being a greenhouse gas, methane emanations and/or leaks are important to consider for both safety and environmental reasons. On this regard, passive remote sensing represents an interesting approach since it allows characterization of large areas from a safe location. In order to illustrate the potential of passive thermal infrared hyperspectral imaging for research on natural gas, imaging was carried out on a shale gas leak that unexpectedly happened during a geological survey near Hospital Enfant-Jesus (Québec City, Canada) in December 2016. Quantitative methane imaging was carried out based on its unique infrared spectral signature. The results show how this novel technique could be used for advanced research on shale gases.

19

Device for emissivity estimation in LWIR range

Olbrycht R.

Measurement Automation Monitoring

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2017

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Vol. 63, No. 3

90--93

EN

The paper deals with the influence of emissivity on infrared measurements (Tab. 1; Fig. 1-3) and presents the developed device for emissivity estimation (Fig. 4). There is comparison shown between the reference emissivity values measured with thermal camera (Fig. 5) and estimated with the developed device (Tab. 2). Obtained results are in good agreement for three examined samples with emissivity ranging from 0.1 to 0.95.

20

Application of neural networks in diagnostics of chemical compounds based on their infrared spectra

Macek-Kamińska K., Stemplewski S.

Ecological Chemistry and Engineering. S

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2017

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Vol. 24, nr 1

107--118

EN

The paper presents possibilities of using the so-called „finger-print“ identification method and artificial neural network (ANN) for diagnosis of chemical compounds. The construction of a tool specifically developed for this purpose and the ANN, as well as the required conditions for its proper functioning were described. The identification of chemical compounds was tested in two different ways for proving correctness of the assumptions. First of all, initial studies were carried out with the objective to verify the proper functioning of the developed procedure for IR spectrum interpretation. The second research stage was to find out how the properties of artificial neural networks will satisfy identification or differentiation in case of spectra with very similar structures or for mixtures consisting of several chemical compounds. Interpretation of infrared spectra of mono-constituent substances was successfully performed for both - the training and test data. Interpretation process of infrared spectra of bi-component substances, based on the example of structurally related compounds obstructing identification process, should also be described as positive. The model was able to interpret spectra of mixtures, which were previously registered into the database. Unfortunately, the program is not always able to determine which chemical substances reflect their presence in the infrared spectrum of ternary mixtures. During the research tests, it was also noted that the more complex the structure of a substance being present in the mixture was, the more difficult the interpretation of the spectra to be carry out properly by the program was. On the other hand, positive results were obtained for mixtures of compounds with not so complex structure. It must be emphasized that the results so far are promising and more attention should be paid to them in further studies.