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Wyszukujesz frazę "optical analysis" wg kryterium: Temat


Tytuł:
Estimating solid contaminant levels in beach sands through petrographic analysis, screening evaluation, and optical imaging
Autorzy:
Kuś, Sebastian
Jelonek, Zbigniew
Jelonek, Iwona
Sierka, Edyta
Powiązania:
https://bibliotekanauki.pl/articles/27311567.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
beach
optical analysis
petrographic analysis
solid pollution
Opis:
Determining the level of solid pollution in beach sands located near artificial inland water bodies in order to maintain high safety standards is a difficult and expensive task. The tests aimed at determining beach pollution caused by solid wastes through analysis of toxic and chemical concentrations, are time-consuming and usually require several days before the results are available. In addition, the maintenance of the beach area involving beach raking or grooming, and the seasonal replenishment of sand makes it difficult to realistically determine the chemical or bacterial contamination of the tested material. Solid pollutants, such as glass, caps, cans, thick foil, metal, and plastic fragments, pose a greater health risk to beachgoers. The above-mentioned pollutants, especially small ones, are hardly visible on the surface or they are buried at shallow depths. Beach garbage poses a serious threat that can lead to infections from cuts and scratches. These injuries can become infected, further jeopardizing the health and lives of beachgoers due to risks like tetanus, staphylococcus, etc. The authors presented a new petrographic method aimed at assessing the quality of sand by examining the content of solid pollutants. The obtained results allowed us to conclude that the mentioned procedure can be used for a quick quantitative estimation of the content of potentially dangerous and undesirable pollutants in beach sands. Consequently, the method implemented to determent the amount of solid pollutants in beach sands has proven to be a valuable tool for recreational facility administrators, helping them in taking necessary measures to ensure the safety of beach users. Petrographic analysis of beach sands revealed the presence of pollutants of plant origin (0.4–1.8%), plastic (0.1–0.4%), paper (0.1–0.6%), charcoal (0.1–0.5%), glass (0.1–0.4%), metals (0.1–0.4%), rust (0.1–0.3%), ash and slag (0.1–0.3%), and fossil coals (0.1–0.2%).
Źródło:
Archives of Environmental Protection; 2023, 49, 3; 50--63
2083-4772
2083-4810
Pojawia się w:
Archives of Environmental Protection
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Geometrical and optical analysis of small-sized parabolic trough collector using ray tracing tool SolTrace
Autorzy:
Singh, Raman Kumar
Chandra, Prakash
Powiązania:
https://bibliotekanauki.pl/articles/27312206.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
parabolic trough collector
SolTrace
Monte Carlo ray tracing method
nonuniform heat flux distribution
optical analysis
geometrical analysis
Opis:
The present work is aimed at geometrical optimization and optical analysis of a small-sized parabolic trough collector (PTC). Improving the performance of parabolic trough collectors can greatly justify the use of solar energy. An optimized curvature geometry, the location of the absorber tube, and the heat flux distribution along the circumference of the absorber tube are major features in the geometric optimization and optical modelling of parabolic trough collectors. Rim angle, aperture width, the diameter of the absorber tube, receiver position, and the optimum value of heat flux are the major parameters considered in this work for geometrical and optical analysis. The Monte Carlo ray tracing method has been adopted for analysis. The non-uniform heat flux distribution profile obtained from optical analysis of the proposed parabolic trough collector has been compared with the profile available in the literature, and good agreement has been obtained, which proves the feasibility and reliability of the model and method used for this study. An experimental new small-sized parabolic trough collector has been fabricated for the optimized rim angle of 90 deg after a successful laser light feasibility test. The effect of the absorber tube position along the optical axis on the heat flux profile was analysed and found to be substantial. Furthermore, the sensitivity analysis of the parabolic trough collector using the software applied has been discussed separately.
Źródło:
Archives of Thermodynamics; 2023, 44, 3; 35--61
1231-0956
2083-6023
Pojawia się w:
Archives of Thermodynamics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Distribution of EC and OC temperature fractions in different research material
Dystrybucja frakcji temperaturowych EC i OC w różnych materiałach badawczych
Autorzy:
Błaszczak, Barbara
Mathews, Barbara
Słaby, Krzysztof
Klejnowski, Krzysztof
Powiązania:
https://bibliotekanauki.pl/articles/27311564.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
wet deposition
carbonaceous matter
fine PM
thermal-optical analysis
mokra depozycja
analiza termooptyczna
materia węglowa
próbki węgla
Opis:
The aim of the study was to assess the profile of EC (elemental carbon) and OC (organic carbon) temperature fractions in PM1 and PM2.5 samples and in wet deposition samples (material collected on a filter). The research was conducted at the urban background station in Zabrze (southern Poland) in the period of Oct 2020–Oct 2021. PM samples were collected with high-volume samplers; the automatic precipitation collector NSA 181 by Eigenbrodt was used to collect the deposition samples. Concentrations of EC and OC were determined using thermal-optical method (carbon analyzer from Sunset Laboratory Inc., “eusaar_2” protocol). Regardless of the type of research material, organic carbon constituted the dominant part of the carbonaceous matter, and this dominance was more visible in the non-heating season. The profile of temperature fractions of OC and EC was clearly different for dust washed out by precipitation. Noteworthy is a much lower content of pyrolytic carbon (PC) in OC, which can be explained by the fact that PC is most often combined with the water soluble organic carbon. In addition, a high proportion of the OC3 fraction was observed, followed by OC4, which may indicate that these fractions are of a more regional origin. With regard to the EC fractions, the differences are less visible and concern, in particular, the higher share of EC4 and the lower of EC2. The obtained results may be a valuable source of information about the actual status of the carbonaceous matter and its transformation in the atmosphere .
Celem badań była ocena profilu frakcji temperaturowych EC (węgiel elementarny) i OC (węgiel organiczny) w próbkach PM1 i PM2,5 oraz w próbkach depozycji mokrej (materiał zgromadzony na sączku). Badania przeprowadzono na stacji tła miejskiego w Zabrzu w okresie X 2020–X 2021. Próbki PM pobierano za pomocą poborników wysoko-objętościowych. Do poboru próbek depozycji zastosowano automatyczny kolektor opadów NSA 181 firmy Eigenbrodt. Stężenia EC i OC oznaczono metodą termiczno-optyczną (analizator węgla firmy Sunset Laboratory Inc., protokół „eusaar_2”). Niezależnie od rodzaju materiału badawczego węgiel organiczny stanowił dominującą część materii węglowej, a dominacja ta była bardziej widoczna w sezonie niegrzewczym. Profil frakcji temperaturowych OC i EC różnił się wyraźnie dla pyłu z depozycji mokrej. Na uwagę zasługuje znacznie niższa zawartość węgla pirolitycznego (PC) w OC, co można tłumaczyć tym, że PC jest najczęściej łączony z rozpuszczalnym w wodzie węglem organicznym. Ponadto zaobserwowano wysoki udział frakcji OC3, a następnie OC4, co może wskazywać na bardziej regionalne pochodzenie tych frakcji. W przypadku frakcji EC różnice są mniej widoczne i dotyczą w szczególności wyższego udziału EC4 i mniejszego EC2. Uzyskane wyniki mogą być cennym źródłem informacji o materii węglowej i przemianom jakim podlega w atmosferze.
Źródło:
Archives of Environmental Protection; 2023, 49, 2; 95--103
2083-4772
2083-4810
Pojawia się w:
Archives of Environmental Protection
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Spectral analysis for tilted fiber Bragg gratings in the corrosion detection for concrete structure
Autorzy:
Kwong, Kok Zee
Udos, Waldo
Lim, Kok-Sing
Lee, Foo Wei
Tan, Chee Ghuan
Samion, Muhamad Zharif
Ahmad, Harith
Powiązania:
https://bibliotekanauki.pl/articles/2172827.pdf
Data publikacji:
2022
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
tilted fibre Bragg grating
optical spectral analysis
Fourier transform
corrosion
steel bar
Opis:
An effective corrosion monitoring technique is sought after by the engineers for assessing the steel bar corrosion at the early stage for the maintenance and repair works, especially in the corrosive environments, such as coastal and marine. In this work, tilted fiber Bragg grating (TFBG) with the optical sensor is employed in corrosion monitoring of a reinforced concrete structure. Taking advantage of the high sensitivity of TFBG cladding resonance wavelengths to the change in the surrounding medium, the sensor is mounted on the steel bar that is embedded in a concreted block during an accelerated corrosion process. The acquired transmission spectrum of the TFBG during the procedure is digitally processed using Fourier Transform to produce an index that is sensitive to the generated corrosion product surrounding the TFBG sensor. This eases the analysis of the sophisticated TFBG transmission spectra. The generated index can be used as an indicator (indicator J ) for the corrosion process of the embedded steel bar in the concrete structure. This indicator J can act as an indicator to describe the corrosion activity and corrosion level at a specific point of the steel bar in concrete structures.
Źródło:
Optica Applicata; 2022, 52, 3; 429--439
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparative study on combustion characteristics of lean premixed CH4/air mixtures in RCM using spark ignition and turbulent jet ignition in terms of orifices angular position change
Autorzy:
Bueschke, Wojciech
Skowron, Maciej
Wisłocki, Krzysztof
Szwajca, Filip
Powiązania:
https://bibliotekanauki.pl/articles/973119.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Naukowe Silników Spalinowych
Tematy:
CNG
turbulent jet ignition
prechamber
optical analysis
flame development
heat release rate
turbulentny zapłon odrzutowy
komora wstępna
analiza optyczna
szybkość wydzielania ciepła
Opis:
The increase in ignitability consist a main aim of implementation of the turbulent jet ignition (TJI) in relation to the combustion of diluted charges. Such an ignition system has been introduced to the lean-burn CNG engine in the scope of GasOn-Project (Gas Only Internal Combustion Engines). In this study the impact of TJI application on the main combustion indexes has been investigated using RCM and analyzed on the bases of the indicating and optical observations data. The images have been recorded using LaVision HSS5 camera and post-processed with Davis software. Second part of the study based on indicating measurements consist the analysis of combustion regarding the variation in the geometry of pre-chamber nozzles. It has been noted, that combustion with TJI indicates significantly bigger flame luminescence and simultaneously - faster flame front development, than the combustion initiated with conventional SI. The positive impact of nozzles angular position on engine operational data has been found in the static charge movement conditions, regarding the combustion stability.
Źródło:
Combustion Engines; 2019, 58, 1; 36-41
2300-9896
2658-1442
Pojawia się w:
Combustion Engines
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analiza termiczna – interpretacja krzywych. Cz. 4, Pomiary TGA
Autorzy:
Schulnell, M.
Powiązania:
https://bibliotekanauki.pl/articles/273952.pdf
Data publikacji:
2016
Wydawca:
Roble
Tematy:
analiza termiczna
analiza termograwimetryczna
TGA
skaningowa kalorymetria różnicowa
DSC
analiza termomechaniczna
TMA
dynamiczna analiza mechaniczna
DMA
analiza termooptyczna
TOA
thermal analysis
thermogravimetric analysis
differential scanning calorimetry
thermomechanical analysis
dynamic mechanical analysis
thermal-optical analysis
Opis:
W artykule omówiono różne kwestie odnoszące się do pomiarów TGA. Wykazano również, że inne techniki analizy termicznej takie jak różnicowa kalorymetria skaningowa (DSC), analiza termomechaniczna (TMA), dynamiczna analiza mechaniczna (DMA) i analiza termooptyczna (TOA) mogą w istotny sposób ułatwiać interpretację wyników pomiarów TGA.
Źródło:
LAB Laboratoria, Aparatura, Badania; 2016, 21, 4; 6-13
1427-5619
Pojawia się w:
LAB Laboratoria, Aparatura, Badania
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ocena narażenia zawodowego na węgiel elementarny w zakładach stosujących maszyny i urządzenia z silnikami wysokoprężnymi
Assessment of occupational exposure to elemental carbon in plants using diesel machinery and equipment
Autorzy:
Szewczyńska, Małgorzata
Kowalska, Joanna
Pośniak, Małgorzata
Powiązania:
https://bibliotekanauki.pl/articles/2188905.pdf
Data publikacji:
2023-05-19
Wydawca:
Instytut Medycyny Pracy im. prof. dra Jerzego Nofera w Łodzi
Tematy:
narażenie zawodowe
ocena narażenia
węgiel elementarny
spaliny silników wysokoprężnych
analiza termo-optyczna
marker spalin Diesla
occupational exposure
exposure assessment
elemental carbon
diesel exhaust
thermo-optical analysis
diesel exhaust marker
Opis:
Wstęp W artykule przedstawiono i omówiono wyniki oznaczania węgla elementarnego (elemental carbon – EC) emitowanego w spalinach silników Diesla (SSD) do powietrza stanowisk pracy, na których były wykorzystywane maszyny i urządzenia z takimi silnikami. Narażenie zawodowe na EC jako marker SSD oceniono, obejmując pomiarami 51 naziemnych stanowisk pracy z obsługą lub konserwacją silników Diesla. Przeprowadzono również pomiary na 9 stanowiskach pracy w kopalniach niewęglowych. Materiał i metody Do pobierania próbek powietrza na stanowiskach pracy maszyn i urządzeń emitujących SSD zlokalizowanych na powierzchni do oznaczania EC wykorzystano próbnik kasetowy bez impaktora z filtrem kwarcowym, a w przypadku pomiarów w kopalniach niewęglowych – próbnik do frakcji respirabilnej typu Higgins-Dewell Cyclone FH022. Do oznaczania EC zastosowano metodę analizy termo-optycznej węgla z wykorzystaniem detektora płomieniowo-jonizacyjnego. Wyniki Analiza wyników pomiarów na stanowiskach pracy zlokalizowanych na powierzchni, tj. w warsztatach samochodowych i hucie stali, wykazała, że największe stężenia EC występowały na stanowiskach pracy związanych z obsługą starych wózków widłowych. Oznaczone tam stężenia EC wynosiły, odpowiednio, 353 μg/m³ i 78 μg/m³. W kopalniach niewęglowych stężenie EC wynosiło natomiast 7,5–50 μg/m³. Wnioski Ocena narażenia na badanych stanowiskach w hucie stali wykazała największe, 7-krotne, przekroczenie najwyższego dopuszczalnego stężenia (NDS) na stanowisku operatora spalinowego wózka widłowego. Na pozostałych badanych stanowiskach pracy w warsztatach samochodowych oznaczone stężenia wynosiły 0,1–0,5 NDS lub <0,1 NDS. W kopalniach niewęglowych oznaczone stężenia odpowiadały natomiast 0,12–1 krotności NDS. Med. Pr. 2023;74(2)
Background This paper presents and discusses the results of the determination of elemental carbon emitted in diesel engine exhaust into the air of workplaces where machines and equipment with diesel engines are used. In order to assess occupational exposure to elemental carbon (EC) as a marker of exhaust gases emitted by diesel engines, 51 ground-based workplaces where people who operate or maintain equipment with this type of engine work were measured. Measurements were also carried out at 9 workplaces in non-coal mines. Material and Methods For air sampling at workplaces of diesel exhaust emitting machines and equipment located on the surface, a cartridge sampler without an impactor with a quartz filter was used for elemental carbon determination, while for measurements in non-coal mines the Higgins-Dewell Cyclone FH022 respirable fraction sampler was used. The thermo-optical carbon analysis method using a flame ionisation detector was used to determine elemental carbon. Results Analysis of the results of the determined elemental carbon concentrations at workplaces located on the ground, i.e., in car repair shops, and in the steelworks where combustion forklifts are operated, showed that the highest concentrations of elemental carbon were determined at the old forklift workplaces in the steelworks. The determined EC concentrations at these workstations were 353 μg/m³ and 78 μg/m³, respectively. In the non-coal mines, elemental carbon concentrations were in the range of 7.5–50 μg/m³. Conclusions Exposure assessment at the surveyed workplace in the steelworks showed the highest 7-fold exceedance of the maximum admissible concentration (MAC) at the position of the combustion forklift operator. At the other surveyed workplaces in the car repair shop the marked concentrations were in the range of 0.1–0.5 MAC or <0.1 MAC. In non-coal mines, the determined concentrations ranged 0.12–1 times the MAC. Med Pr. 2023;74(2)
Źródło:
Medycyna Pracy; 2023, 74, 2; 93-102
0465-5893
2353-1339
Pojawia się w:
Medycyna Pracy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Shape accuracy in single point incremental forming of conical frustums from titanium CP2 sheets
Dokładność kształtu w jednopunktowym kształtowaniu przyrostowym stożków ściętych z blach tytanowych CP2
Autorzy:
Szpunar, Marcin
Balcerzak, Maciej
Żaba, Krzysztof
Powiązania:
https://bibliotekanauki.pl/articles/2204384.pdf
Data publikacji:
2022
Wydawca:
Politechnika Rzeszowska im. Ignacego Łukasiewicza. Oficyna Wydawnicza
Tematy:
incremental sheet forming
titanium
springback
optical forming analysis
X-ray tomography
kształtowanie przyrostowe blach
tytan
sprężynowanie
analizy optyczne kształtowania
tomografia komputerowa
Opis:
This paper presents frustum cone drawpiece analysis made of titanium CP2 sheet by a single incremental sheet forming. Central composite design has been adopted to carry out an experiment containing 20 runs, then multi-criteria parameter optimization has been done. Optimal parameters have been validated and responses deviations do not exceed 4% compared to created models. For the drawpiece formed with optimal parameters, AGRUS optical measurement and X-ray tomography has been applied to check the obtained of the part wall thickness and general deviations compared to the CAD model. The wall angle discrepancy of the cone generatrix has also been analyzed. No gaps or ruptures have been confirmed by X-ray. The blank rolling direction has a significant effect on the drawpiece deviations. The measurement results showed deviations of the drawpiece wall angle +0.27°/- 0.06°, sheet thickness on the cone +0.012/-0.04 mm and +0.151/-0.096 mm from the reference CAD geometry.
W pracy przedstawiono analizę wytłoczek w kształcie stożka ściętego wykonanego z blachy tytanowej CP2 metodą jednopunktowego przyrostowego kształtowania. Do przeprowadzenia eksperymentu obejmującego 20 przebiegów przyjęto centralny plan kompozycyjny, następnie dokonano wielokryterialnej optymalizacji parametrów. Dokonano walidacji optymalnych parametrów, a uzyskane wyniki nie przekraczają 4% w odniesieniu do stworzonych modeli. Dla wytłoczki uformowanej z optymalnymi parametrami zastosowano pomiar optyczny AGRUS oraz tomografię rentgenowską w celu sprawdzenia uzyskanej grubości ścianki wytłoczki i odchyłek w porównaniu z modelem CAD. Przeanalizowano również rozbieżność kątów ścian tworzących stożka. Za pomocą skanu rentgenowskiego potwierdzono brak szczelin i pęknięć wytłoczki. Kierunek walcowania półfabrykatu ma istotny wpływ na odchyłki. Wyniki pomiarów wykazały odchylenia kąta ścianki wytłoczki +0,27/-0,06°, grubości ścianki na stożku +0.012/-0.04 mm oraz +0.151/-0.096 mm od geometrii referencyjnej CAD.
Źródło:
Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika; 2022, z. 94; 63--75
0209-2689
2300-5211
Pojawia się w:
Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Determination of the optode array representation using optical properties at systole and diastole
Autorzy:
Jumadi, N A
Beng, G K
Mohd-Ali, M. A.
Zahedi, E
Powiązania:
https://bibliotekanauki.pl/articles/173805.pdf
Data publikacji:
2013
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
optical simulation
optical properties
optode array
semi-infinite tissue layer
statistical
analysis
Opis:
The necessity to develop an optode array in order to probe the fetus oxygenation noninvasively regardless of the fetus position has been highlighted in previous literature. In this paper, a series of optical simulations are carried out to determine the best representation of optode array by using optical properties at systolic and diastolic states. The selection is based on the highest flux values accumulated at respective detectors. To accomplish the objective, a homogenous three-layer semi-infinite tissue model is implemented to represent the pregnant woman model. The geometry of the model as well as Monte Carlo simulation are carried out using commercial software, whereas the optical properties related to systolic and diastolic states are defined for all wavelengths. A statistical noise analysis is also introduced in order to find a sufficient number of rays to be launched into the optical tissue system.
Źródło:
Optica Applicata; 2013, 43, 4; 747-759
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Separation of isochromatics and isoclinics phasemaps for the photoelastic technique with use phase shifting and a large number of high precision images
Autorzy:
Magalhaes, C. A.
Neto, P. S.
Magalhaes Jr P. A., A.
de Barcellos, C. S.
Powiązania:
https://bibliotekanauki.pl/articles/220820.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
photoelasticity
metrology
stress analysis
strain measurement
optical measurement systems
optical interferometry
experimental techniques
Opis:
Digital photoelasticity is an important optical metrology follow-up for stress and strain analysis using full-field digital photographic images. Advances in digital image processing, data acquisition, procedures for pattern recognition and storage capacity enable the use of the computer-aided technique in automation and facilitate improvement of the digital photoelastic technique. The objective of this research is to find new equations for a novel phase-shifting method in digital photoelasticity. Some innovations are proposed. In terms of phaseshifting, only the analyzer is rotated, and the other equations are deduced by applying a new numerical technique instead of the usual algebraic techniques. This approach can be used to calculate a larger sequence of images. Each image represents a pattern and a measurement of the stresses present in the object. A decrease in the mean errors was obtained by increasing the number of observations. A reduction in the difference between the theoretical and experimental values of stresses was obtained by increasing the number of images in the equations for calculating phase. Every photographic image has errors and random noise, but the uncertainties due to these effects can be reduced with a larger number of observations. The proposed method with many images and high accuracy is a good alternative to the photoelastic techniques.
Źródło:
Metrology and Measurement Systems; 2013, 20, 1; 127-138
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparative accuracy analysis of triangulated surface models of a fossil skull digitized with various optic devices
Autorzy:
Garashchenko, Yaroslav
Kogan, Ilja
Rucki, Mirosław
Powiązania:
https://bibliotekanauki.pl/articles/2052109.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Madygenerpeton
optical measurement
triangulated model
polygonal analysis
accuracy
Opis:
Digital metrology was applied for evaluate 3D models of the unique skull of a fossil tetrapod, Madygenerpeton pustulatum, generated using various 3D digitization methods. The skull surface is covered by minute tubercles making it challenging for digitization with appropriate accuracy. Uniqueness and fragility of the specimen preclude the use of tactile measuring systems for creating a standardized reference model. To overcome this problem, comparative analysis of the triangulated models generated from the clouds of points obtained with seven different devices was conducted using the Geomagic Studio and Autodesk PowerShape CAD software. In the proposed approach, geometrically and dimensionally closest-fitting models underwent detailed statistical analysis between surface polygons in three steps. First, 3D models obtained from different scanning methods were compared with each other in couples. Next, statistical analysis of the differences between the coupled models was performed. Finally, a rating list of the models related to the required accuracy was prepared. The proposed approach is applicable to any other scanned object, especially in palaeontological applications, where each object is unique and exhibits individual features.
Źródło:
Metrology and Measurement Systems; 2022, 29, 1; 37-51
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Spectral analysis by a video camera in a holographic optical tweezers setup
Autorzy:
Drobczynski, S
Dus-Szachniewicz, K
Symonowicz, K.
Glogocka, D
Powiązania:
https://bibliotekanauki.pl/articles/174701.pdf
Data publikacji:
2013
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
holographic optical tweezers
power spectrum density
video analysis
Opis:
We discuss the basic parameters of the holographic tweezers equipped with a diode laser and cheap video camera. We compare these parameters with the system using a fast camera and high power Nd:YAG laser. The measured parameters are: the power spectra density calculated from tracing the position of the micron polystyrene beads and the trap stiffness. We show that this cheap optical tweezers system is sufficient for experiments in microbiology.
Źródło:
Optica Applicata; 2013, 43, 4; 739-746
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical Analysis of Material and Manufacturing Factors in Riveted Joints Under the Imperja Project
Autorzy:
Szymczyk, E.
Bogusz, P.
Sławiński, G.
Jachimowicz, J.
Powiązania:
https://bibliotekanauki.pl/articles/97935.pdf
Data publikacji:
2012
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Lotnictwa
Tematy:
riveted joints
fatigue strength
optical methods
SEM analysis
Opis:
The aim of the project was to improve fatigue performance of riveted joints in airframes. Fatigue strength of a joint depends on structural, material and manufacturing factors. The project involved numerical and experimental analysis of material factors and manufacturing imperfections. The paper deals with the analysis of material structure and properties by means of the optical and SE methods. Static monotonic tests for sheet and rivet materials were carried out. ARAMIS optical system was used for the study of deformation and strain fields in the material during loading. This tool offers the possibility of a non-contact measurement with 3D image correlation methods (digital image correlation, DIC) using high-resolution digital CCD cameras. In ductile materials (such as aluminium alloy), subjected to appropriate loading conditions, voids may form, which grow and coalesce leading to crack formation and potential failure. A micro crack may be initiated at the inclusion particles and then voids grow around it. Experimental studies showed that these processes are strongly influenced by hydrostatic stress (Gurson’s material model). SEM analysis of material structure was carried out after performing static tests. In the paper, the authors present the influence of a material model on the results of numerical simulation of the tensile loaded samples with open and riveted holes. The application of Gurson’s material model allows observation of crack growth in the sample cross-section and determination of the sheet rupture as the moment when constraint force decreases to zero (material separation occurs).
Źródło:
Fatigue of Aircraft Structures; 2012, 4; 100-113
2081-7738
2300-7591
Pojawia się w:
Fatigue of Aircraft Structures
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Novel rogue optical network unit detection algorithm for gigabit passive optical networks
Autorzy:
Horvath, T.
Munster, P.
Dubravec, L.
Filka, M.
Powiązania:
https://bibliotekanauki.pl/articles/174637.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
gigabit passive optical network
GPON
rogue optical network unit
ONU
data analysis
detection algorithm
Opis:
Passive optical networks are widely used as a promising solution for future access networks. Currently, the bandwidth is still increasing which means the current copper networks are not able to transfer new services such as 4K video, live streaming, etc. In other words, they reached their capacity limit. The passive optical networks rely on point-to-multipoint technology. That means each customer uses a share medium by time slots. Each time slot exactly specifies who and when is able to transfer data. In general, this control mechanism is implemented in the optical network unit by worst transmission convergence layer. On the other hand, there are cases when the optical network unit (it is called rogue optical network unit) does not follow instructions provided by the optical line termination, for example, if an attacker modifies a firmware of the end unit and/or when the control protocol is not loaded properly inside optical network unit. In worst case, the optical network unit transmits data in a continual mode (other optical network units cannot send data). Thestandard defines finding of the rogue optical network unit but it does not specify how the rogue optical network unit should be allocated because the frames of the rogue optical network unit do not contain the proper parameters. We realized a measurement in a real network with the rogue optical network unit and then we analyzed the captured data. A new algorithm for the rogue optical network unit allocation is presented. We do not consider any modification of the transmission convergence layer in gigabit passive optical networks.
Źródło:
Optica Applicata; 2016, 46, 3; 421-433
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Simulation research of bionic image intensifier based on the retina structure of elephant-nose fish
Autorzy:
Zhang, Hongxia
Jin, Qingwen
Li, Peng
Jia, Dagong
Liu, Tiegen
Powiązania:
https://bibliotekanauki.pl/articles/1835814.pdf
Data publikacji:
2020
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
geometric optical design
micro-optical device
image analysis
low-light night vision
bionic image intensifier
Opis:
Enhancing image brightness under low light conditions is crucial. The traditional night vision technology depends on the development of photoelectric materials and accurate image processing algorithms. Inspired by the structure of elephant-nose fish, we construct a bionic image intensifier (BII) model. The BII is a planar array based on the concentrating principle of the compound parabolic concentrator (CPC). This solution is based on pure optical design and independent. Through light tracing, the simulation results show that the brightness of the image is improved and good image uniformity is obtained. Quantitative analysis of the geometric concentration ratio (GCR) and the image uniformity is used to optimize CPC structure parameters. At the same time, we also discuss the influence of CPC structural parameters on image continuity, uniformity and geometric concentration ratio. The optimization results are as follows: the input port diameter is 50 μm, the output port diameter is 10 μm, the height is 90 μm, the GCR is 5.61, and the image uniformity is 95.30%. The comprehensive performance of the BII achieves the best.
Źródło:
Optica Applicata; 2020, 50, 4; 551-566
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł

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