Skocz do pozycji: 1.

Tytuł:

Significance of the receding contact angle in the determination of surface free energy

Autorzy:

Chodkowski, Michał Paweł

Powiązania:

https://bibliotekanauki.pl/articles/2079958.pdf

Data publikacji:

2018

Wydawca:

Uniwersytet Marii Curie-Skłodowskiej. Wydawnictwo Uniwersytetu Marii Curie-Skłodowskiej

Tematy:

receding contact angle
equilibrium contact angle
Tadmor’s contact angle
CAH
surface free energy

Opis:

Surface free energy measurements of solids are a very important issue in various fields of science. Many functional, chemical and physical properties of a given material depend on its surface free energy. The basic method of the surface free energy determination are the contact angle measurements. There are several empirical methods useful to calculate the surface free energy of solids. They are based on the measurements of the contact angle of liquids with the defined surface tension. The aim of this paper is to examine the significance of the receding contact angle measurements in the determination of surface free energy of solids.

Źródło:

Annales Universitatis Mariae Curie-Skłodowska, sectio AA – Chemia; 2018, 73, 1; 61-80
2083-358X

Pojawia się w:

Annales Universitatis Mariae Curie-Skłodowska, sectio AA – Chemia

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 2.

Tytuł:

A method for the estimation of sideslip angle for a vehicle equipped with a one-antenna GPS measuring system for steady state movement

Autorzy:

Pieniążek, Wiesław
Wolak, Stanisław
Janczur, Robert

Powiązania:

https://bibliotekanauki.pl/articles/263758.pdf

Data publikacji:

2019

Wydawca:

Sieć Badawcza Łukasiewicz. Przemysłowy Instytut Motoryzacji

Tematy:

sideslip angle
heading angle
yaw angle
yaw rate
GPS receiver signals

Opis:

One-antenna GPS systems present no possibility for the direct determination of vehicle slip angle. This is an easy task for dual antenna systems; however, many users have this kind of apparatus. In this paper, a method of estimation of this parameter, which is important for the estimation of vehicle steerability factors, is proposed (e.g. TB factor calculated on the basis of data from input test [8]). The method is based on two parameters measured by a one-antenna GPS system; these are the heading angle created from the Doppler channel coming directly from the GPS engine, and the yaw rate measured by an IMU device integrated and cooperating with the GPS engine. The sideslip angle which was calculated according to the proposed method is compared with an equivalent angle calculated on the basis of data from a non-slip measurement of velocity components for selected point of vehicle acquired using. The presented method is illustrated with examples from real tests. In the author’s opinion, the sideslip angle calculated with the application of measurement data obtained from a one-antenna GPS device could be used in practice. From comparison with another upper mentioned method, it follows that the differences between average values of sideslip angles obtained from both considered methods is not greater than 8%.

Źródło:

Archiwum Motoryzacji; 2019, 84, 2; 137-146
1234-754X
2084-476X

Pojawia się w:

Archiwum Motoryzacji

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 3.

Tytuł:

An improved angle calibration method of a high-precision angle comparator

Autorzy:

Xia, Yangqiu
Wu, Zhilin
Huang, Ming
Liu, Xingbao
Mi, Liang
Tang, Qiang

Powiązania:

https://bibliotekanauki.pl/articles/1848955.pdf

Data publikacji:

2021

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

angle calibration
position error
complete closure method
method verification

Opis:

Angle calibrations are widely used in various fields of science and technology, while in the high-precision angle calibrations, a complete closure method which is complex and time-consuming is common. Therefore, in order to improve the measurement efficiency and maintain the accuracy of the complete closure method, an improved calibration method was proposed and verified by the calibration of a high-precision angle comparator with sub-arc-second level. Firstly, a basic principle and algorithm of angle calibration based on complete closure and symmetry connection theory was studied. Then, depending on the pre-established calibration system, the comparator was respectively calibrated by two calibration methods. Finally, by comparing En values of two calibration results, the effectiveness of the improved method was verified. The calibration results show that the angle comparator has a stable angle position error of 0.17′′ and a measurement uncertainty of 0.05′′ (k=2). Through method comparisons, it was shown that the improved calibration method can greatly reduce calibration time and improve the calibration efficiency while ensuring the calibration accuracy, and with the decrease of measurement interval, the improvement of calibration efficiency was more obvious.

Źródło:

Metrology and Measurement Systems; 2021, 28, 1; 181-190
0860-8229

Pojawia się w:

Metrology and Measurement Systems

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 4.

Tytuł:

A dynamic angle metrology system based on fibre-optic gyroscope and rotary table

Autorzy:

Chen, Lei
Zhou, Yilan
Zhang, Dengwei
Shu, Xiaowu
Liu, Cheng

Powiązania:

https://bibliotekanauki.pl/articles/220999.pdf

Data publikacji:

2019

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

circular grating angle encoder
fibre-optic gyroscope
dynamic angle metrology

Opis:

Dynamic angle measurement (DAM) plays an important role in precision machining, aerospace, military and artificial intelligence. Because of its advantages including high sensitivity, solid state and miniaturization, fibre-optic gyroscope (FOG) has great application prospects in the field of DAM. In this paper, we propose a dynamic angle metrology method based on FOG and a rotary table to evaluate the DAM accuracy with FOG. The system synchronously collects data from the FOG and rotary table, and analyses the DAM accuracy of the FOG for different sway conditions compared with that of the angle obtained from the rotary table. An angle encoder in the rotary table provides absolute or incremental angular displacement output with angular displacement measurement accuracy of 10′′ (0:0028°) and angular displacement repeat positioning accuracy of 3′′ (0:00083°), and can be used as an angle reference. The experimental results show that the DAM accuracy of the FOG is better than 0:0028° obtained with the angular encoder, and the absolute DAM accuracy of the FOG is better than 0:0048° for given conditions. At the same time, for the multi-path signal synchronization problem in the metrology field, this paper proposes a signal delay measurement method combining test and algorithm procedures, which can control a delay within 25 μs.

Źródło:

Metrology and Measurement Systems; 2019, 26, 3; 497-504
0860-8229

Pojawia się w:

Metrology and Measurement Systems

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 5.

Tytuł:

Deviation angle models in off-design high-pressure turbines

Autorzy:

Bugała, P.

Powiązania:

https://bibliotekanauki.pl/articles/247825.pdf

Data publikacji:

2018

Wydawca:

Instytut Techniczny Wojsk Lotniczych

Tematy:

turbomachinery
gas turbines
high-pressure turbine
HPT
deviation angle

Opis:

In the article, a set of deviation angle models, which are used to predict the off-design performance high-pressure turbines, has been presented, basing on a literature study. The deviation angle is a deviation between the actual flow angle and the blade inclination angle. It is an essential parameter in turbine performance evaluation. This angle shall be obtained accurately in 1-D design and evaluation, so as to ensure the validity of blade profiling and calculation results. If deviation angle is ignored, the turbine will produce a lower change of tangential velocity, and consequently a lower torque, output work and enthalpy drop than intended by the designer. For this reason, the deviation angle model needs to be established. There exist a number of different deviation models, resulting in varying degrees of flow deviation when applied. In the article, correlations for gas outlet angle, dependent on the Mach number at outlet and determined by the blade loading towards the trailing edge has been presented. The main difficulty in establishing the deviation model is a continuity in defining the angle for all speed ranges (both subcritical and supercritical). Each of the models presented in the article deals with this problem in a different way. A few deviation models, briefly discussed in the article, are based on experimental data and one is based on analytical approach.

Źródło:

Journal of KONES; 2018, 25, 2; 69-74
1231-4005
2354-0133

Pojawia się w:

Journal of KONES

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 6.

Tytuł:

New gyroplane hub connector with positive coning angle

Autorzy:

Wojtas, M.
Trendak, M.

Powiązania:

https://bibliotekanauki.pl/articles/244662.pdf

Data publikacji:

2017

Wydawca:

Instytut Techniczny Wojsk Lotniczych

Tematy:

blade dihedral angle
waving
rotor instability
teetering rotor

Opis:

The article presents advantages and disadvantages of two blade teetering rotors with constructional dihedral angle greater than 0o . Several structural design solutions of rotor hub connector are shown in this work. However, the main attention is focused on innovative hub connector design and manufactured by Trendak Aviation Company during the project “Research and development works on innovative construction of aircrafts of weight over 560 kilograms”. Discusses structural advantages of the new rotor hub connector according to other construction. Also were raised issues related to the load of the gyroplane rotor during the flight, in particular the load of rotor blades root, during a gyroplane break manoeuvre, according to conning angle of rotor hub connector. The disadvantages of using the structural dihedral angle in teetering rotors are also presented, focusing on the rotor aeroelastic instability so-called waving, which from the literature analysed is concerned only with two blades teetering rotors. Performed a coarse analysis in SMOG program, prepared at the Institute of Aviation for the analysis of helicopter and gyroplanes rotors. The stability analysis of the rotor for a number of structural dihedral angle and blades setting pitch was performed. Basis of this analysis the stability boundary were determined for the analysed gyroplane rotor with connector hub with positive coning angle of 2.8o. .

Źródło:

Journal of KONES; 2017, 24, 3; 325-330
1231-4005
2354-0133

Pojawia się w:

Journal of KONES

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 7.

Tytuł:

Measurement of contact angle of copper-bearing shales using the captive bubble method

Autorzy:

Szyszka, D.

Powiązania:

https://bibliotekanauki.pl/articles/88887.pdf

Data publikacji:

2014

Wydawca:

Politechnika Wrocławska. Wydział Geoinżynierii, Górnictwa i Geologii. Instytut Górnictwa

Tematy:

contact angle
hydrophobicity
hydrophilicity
flotation

Opis:

This paper describes the measurement of contact angle of the natural surface of copper-bearing shales immersed in solutions of selected reagents of various concentrations using captive bubble method. It demonstrates that the copper-bearing shales coming from Legnicko-Głogwski Copper Region develop natural hydrophobic properties in surfactant (frother) solutions and its hydrophobicity decreases from 82⁰ contact angle in distilled water, 78⁰ in C4E1 solutions, 76⁰ in C4E2 solutions, to 75⁰ in dodecylphenol solutions. These data show that the addition of frother causes a decrease of shale hydrophobicity but it can reduce stability of the thin film between the grain and air bubble. It means that flotation of copper-bearing shales in the presence of frother will only be possible provided specific concentrations.

Źródło:

Mining Science; 2014, 21; 83-94
2300-9586
2353-5423

Pojawia się w:

Mining Science

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 8.

Tytuł:

Optimum design of fiber angle and hole orientation of an orthotropic plate

Autorzy:

Zhang, X.
Lu, A.
Wang, S.
Zhang, N.

Powiązania:

https://bibliotekanauki.pl/articles/280011.pdf

Data publikacji:

2018

Wydawca:

Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej

Tematy:

orthotropic plate
fiber orientation angle
hole orientation angle
conformal transformation method
differential evolution algorithm

Opis:

With the goal of decreasing the stress concentration along the hole boundary in an orthotropic plate under inequi-biaxial loadings, an optimum design of the fiber angle and hole orientation is presented. The maximum absolute tangential stress along the hole boundary is taken as the objective function, and the fiber orientation angle and the hole orientation angle are considered as design variables. The conformal transformation method of a complex function and the Differential Evolution (DE) algorithm are used. Two non-circular shapes, ellipse and hexagon are taken as examples to analyze the problem. Based on the results, we can conclude that the major axis of elliptical holes should be designed in the direction of the maximum external loading for a perforated structure in an orthotropic plate. However, the principal direction that has the larger Young’s modulus should be inclined to the direction of the minimum loading, especially for a significantly orthotropic plate.

Źródło:

Journal of Theoretical and Applied Mechanics; 2018, 56, 1; 297-311
1429-2955

Pojawia się w:

Journal of Theoretical and Applied Mechanics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 9.

Tytuł:

Influence of surface curvature on sessile droplet contact angle of nanofuids

Autorzy:

Cieśliński, J. T.
Krygier, K.

Powiązania:

https://bibliotekanauki.pl/articles/175339.pdf

Data publikacji:

2013

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

contact angle
nanofluids
substrate curvature

Opis:

This paper deals with the change in contact angle of droplets for three nanofluids, i.e., water- Al2O3, water-TiO2 and water-Cu. Nanoparticles were tested at the concentration of 0.01, 0.1, and 1% by weight. Although dispersants were not used to stabilize the suspension, the solutions tested exhibited satisfactory stability. Ultrasonic vibration was used in order to stabilise the dispersion of the nanoparticles. Experimental measurements were performed for horizontal stainless steel (316) tube of three diameters, i.e., 1.6, 3 and 5 mm, and flat stainless steel plates. The results obtained show that the contact angle of tested nanofluids depends strongly on nanoparticle concentration as well as the curvature of the substrate.

Źródło:

Transactions of the Institute of Fluid-Flow Machinery; 2013, 125; 3-12
0079-3205

Pojawia się w:

Transactions of the Institute of Fluid-Flow Machinery

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 10.

Tytuł:

Tilt Angle of Wood Dust

Autorzy:

Ockajova, Alena
Banski, Adrian
Tomasz, Rogoziński

Powiązania:

https://bibliotekanauki.pl/articles/24072422.pdf

Data publikacji:

2023

Wydawca:

Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Wydawnictwo Szkoły Głównej Gospodarstwa Wiejskiego w Warszawie

Tematy:

wood dust
tilt angle
cleaning of dust
way of machining

Opis:

Tilt Angle of Wood Dust. The aim of this article is to point out a risk factor – wood dust, which settles on various structures, inclined surfaces in operation and, if not regularly cleaned, it is a source of secondary dust, because it is swirled up again with any movement. By measuring the tilt angle of bulk wood material obtained from sawing on a table circular saw, using different saw blades and wood dust from longitudinal and transverse sanding on a hand belt sander, we determined which characteristics affect it. We found that the size of the particles is an important characteristic, the larger they are, the smaller the tilt angle and also the surface of the pad on which the dust particles settle, wood did not play a significant role in this case. The smallest tilt angle was measured for sawdust from longitudinal sawing of 27°, and the largest tilt angle for wood dust from transverse sanding of oak and was 57° on beech pad.
Kąt nachylenia pyłu drzewnego. Celem tego artykułu jest zwrócenie uwagi na czynnik ryzyka - pył drzewny, który osadza się na różnych konstrukcjach, nachylonych powierzchniach podczas pracy. Jeśli nie jest regularnie usuwany, jest źródłem pyłu wtórnego, ponieważ jest ponownie zawirowywany przy każdym ruchu. Mierząc kąt pochylenia sypkiego materiału drzewnego uzyskanego z piłowania na stołowej pilarce tarczowej, przy użyciu różnych brzeszczotów i pyłu drzewnego ze szlifowania wzdłużnego i poprzecznego na ręcznej szlifierce taśmowej, ustaliliśmy, które cechy mają na to wpływ. Stwierdziliśmy, że rozmiar cząstek jest ważną cechą, im są one większe, tym mniejszy kąt pochylenia, a także powierzchnia podkładki, na której osadzają się cząstki pyłu, drewno nie odgrywało w tym przypadku znaczącej roli. Najmniejszy kąt pochylenia zmierzono dla trocin z piłowania wzdłużnego 27°, a największy kąt pochylenia dla pyłu drzewnego ze szlifowania poprzecznego dębu i wynosił 57° na podkładce bukowej.

Źródło:

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology; 2023, 121; 37--42
1898-5912

Pojawia się w:

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 11.

Tytuł:

Dokładność pomiaru kąta poziomego kamerą CCD
Accuracy of horizontal angle measurement performed with CCD camera

Autorzy:

Naus, K.
Wąż, M.

Powiązania:

https://bibliotekanauki.pl/articles/223186.pdf

Data publikacji:

2011

Wydawca:

Akademia Marynarki Wojennej. Wydział Dowodzenia i Operacji Morskich

Tematy:

nawigacja optoelektroniczna
pomiar kąta kamerą
dokładność pomiaru kąta
navigation optoelectronic
measuring angle with camera
angle measurement accuracy

Opis:

W artykule przedstawiono fragment opisu badań mających na celu ocenę możliwości zastosowania kamer CCD do określania pozycji statku w strefie przybrzeżnej. Skupiono się w nim wyłącznie na teoretycznej ocenie dokładności pomiaru kąta poziomego kamerą CCD. W pierwszej części artykułu opisano metodę obliczania rozdzielczości i błędu średniego pomiaru kąta poziomego między dwoma znakami nawigacyjnymi, zidentyfikowanymi na obrazie zarejestrowanym kamerą CCD. W części drugiej zaprezentowano wykresy rozdzielczości, błędu średniego i tzw. mapę dokładności (rozkładu błędu średniego) pomiaru kąta poziomego kamerą CCD wykonanego względem hipotetycznego układu dwóch znaków nawigacyjnych oraz analizę otrzymanych wyników. Część końcowa zawiera uogólnione wnioski wyprowadzone na podstawie przeprowadzonych badań.
This article presents part of description of the research on possibility to use CCD cameras to fix ship’s position in the coastal zone. It focuses exclusively on the theoretical measurement evaluation of accuracy of the horizontal angle with a CCD camera. The first part of the article describes the method for calculating resolution and a mean error of measurement of the horizontal angle between two navigation aids, identified in the image recorded with the CCD camera. The second part presents diagrams of resolution, a mean error and map accuracy (mean error distribution) of the horizontal angle measurement performed with the CCD camera. The measurement was made I relation to a hypothetical system of two navigation aids and an analysis of the results obtained. The final part contains a generalized conclusions based on the tests.

Źródło:

Zeszyty Naukowe Akademii Marynarki Wojennej; 2011, R. 52 nr 3 (186), 3 (186); 83-94
0860-889X

Pojawia się w:

Zeszyty Naukowe Akademii Marynarki Wojennej

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 12.

Tytuł:

Enhanced visibility of graphene: the effect of the Brewster angle

Autorzy:

Adamson, P.

Powiązania:

https://bibliotekanauki.pl/articles/173884.pdf

Data publikacji:

2017

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

optical characterization
two-dimensional material
graphene
Brewster angle
differential reflectance

Opis:

Visibility and simple optical diagnostics possibilities of graphene layers on dielectric and semiconductor substrates at the Brewster angle are analyzed. The analysis is based on a numerical simulation. Several oxide semiconductors (ITO, ZnO, TiO2), weakly absorbing Si, and strongly absorbing GaAs are considered. It is shown that at the Brewster angle the optical contrast of graphene flakes on a bare semiconductor substrate is actually strong enough to see them under an optical microscope and there is really no need to create an additional interference film on the substrate.

Źródło:

Optica Applicata; 2017, 47, 3; 363-372
0078-5466
1899-7015

Pojawia się w:

Optica Applicata

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 13.

Tytuł:

Effect of chitosan film surface structure on the contact angle

Autorzy:

Jagodzińska, Sylwia
Pałys, Beata
Wawro, Dariusz

Powiązania:

https://bibliotekanauki.pl/articles/2131497.pdf

Data publikacji:

2021

Wydawca:

Sieć Badawcza Łukasiewicz - Polskie Towarzystwo Chitynowe

Tematy:

cellulose
chitosan
contact angle
films
microstructure

Opis:

The aim of this study was to evaluate the influence of the surface microstructure of chitosan films on the contact angle. Films without plasticising additives made of chitosan or regenerated chitosan were selected for the tests. A sessile drop method based on the European Pharmacopoeia was used to determine the contact angle. Due to the method of film production, the contact angle measurements were made on both the top and bottom surfaces of the film. For chitosan or regenerated chitosan films, the method of preparation slightly affected the difference in wettability between the top and bottom of the films, as confirmed by scanning electron microscopy. On the other hand, the wettability of the top and bottom of cellulose films varied greatly depending on the side of the film. Both chitosan and cellulose films had a homogeneous structure. There were differences in the microstructure between the top and the bottom of the sample in the cellulose film, a factor that affected the contact angle and thus the wettability of the surface.

Źródło:

Progress on Chemistry and Application of Chitin and its Derivatives; 2021, 26; 89-100
1896-5644

Pojawia się w:

Progress on Chemistry and Application of Chitin and its Derivatives

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 14.

Tytuł:

Secondary flow structures and resultant exit flow angle fluctuations in high pressure steam turbine stage

Autorzy:

Świdryczuk, J.

Powiązania:

https://bibliotekanauki.pl/articles/1943184.pdf

Data publikacji:

2010

Wydawca:

Politechnika Gdańska

Tematy:

turbine stage
vortices
exit flow angle

Opis:

The object of investigation is the stage, the geometry and flow conditions of which are typical for a series of steam turbines in operation in Polish power plants. The flow analysis is based on the CFD calculations performed using FlowER, a specialized URANS code developed for studying unsteady phenomena in turbine stages and sections. The paper presents flow patterns illustrating the interaction between vortices inside and downstream of the rotor passage and the resultant exit flow angle (EFA) fluctuations recorded at the stage exit. An attempt is made to attribute individual EFA fluctuations to particular vortices and their development stages.

Źródło:

TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2010, 14, 1-2; 15-28
1428-6394

Pojawia się w:

TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 15.

Tytuł:

On orthogonal projection of right angle
O niezmienniku charakterystycznym rzutowania prostokątnego

Autorzy:

Koźniewski, E.

Powiązania:

https://bibliotekanauki.pl/articles/118860.pdf

Data publikacji:

2015

Wydawca:

Polskie Towarzystwo Geometrii i Grafiki Inżynierskiej

Tematy:

invariant
orthogonal projection
right angle
inwariant
rzutowanie prostokątne
kąt prosty

Opis:

In some textbooks Descriptive Geometry characteristic invariant of orthogonal projection is used in the opposite sense than is formulated. The paper presents the complete formulation of the theorem and its simple proof suitable for presentation to students.
W niektórych podręcznikach geometrii wykreślnej niezmiennik charakterystyczny rzutowania prostokątnego jest stosowany w odwrotnym znaczeniu niż jest formułowany. W pracy przedstawiono pełne sformułowanie twierdzenia i jego prosty dowód, nadające się do zaprezentowania studentom.

Źródło:

Journal Biuletyn of Polish Society for Geometry and Engineering Graphics; 2015, 27; 29-31
1644-9363

Pojawia się w:

Journal Biuletyn of Polish Society for Geometry and Engineering Graphics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 16.

Tytuł:

Azimuth angle determination for the arrival direction for an ultrasonic echo signal

Autorzy:

Kreczmer, B.

Powiązania:

https://bibliotekanauki.pl/articles/384597.pdf

Data publikacji:

2017

Wydawca:

Sieć Badawcza Łukasiewicz - Przemysłowy Instytut Automatyki i Pomiarów

Tematy:

ultrasonic range finder
sonar
direction of arrival
azimuth angle

Opis:

In the paper, an idea of a method of signal arrival direction estimation is presented. The influence of time error measurements on the usage of the method is described. An approach to the problem of an increase in the robustness of the method is proposed. The results of experiments are presented and discussed.

Źródło:

Journal of Automation Mobile Robotics and Intelligent Systems; 2017, 11, 2; 31-41
1897-8649
2080-2145

Pojawia się w:

Journal of Automation Mobile Robotics and Intelligent Systems

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 17.

Tytuł:

The effect of the turbulence model on the turbine stage flow exit angle distribuation

Autorzy:

Świrydczuk, J.

Powiązania:

https://bibliotekanauki.pl/articles/1933955.pdf

Data publikacji:

2012

Wydawca:

Politechnika Gdańska

Tematy:

turbine stage
turbulence model
flow exit angle

Opis:

The article analyses the effect of the turbulence model on the calculated exit angles of the flow leaving the rotor of a low-pressure turbine stage. Three turbulence models were taken into account: the algebraic Baldwin-Lomax model and two advanced differential models based on the Shear Stress Transport (SST) approach proposed by Menter. The calculated results have revealed that even such extremely different turbulence models impose little difference in the resultant averaged flow exit angle distributions, especially in stages in which a regular flow pattern without flow separation and/or other irregularities is observed. Larger differences can be observed in local distributions of this parameter, especially in the regions of activity of secondary vortex structures.

Źródło:

TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2012, 16, 3-4; 239-252
1428-6394

Pojawia się w:

TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 18.

Tytuł:

Anthropometric, body composition and behavioural predictors of bioelectrical impedance phase angle in Polish young adults - preliminary results

Autorzy:

Skrzypek, M.
Szponar, B.
Drop, B.
Panasiuk, L.
Malm, M.

Powiązania:

https://bibliotekanauki.pl/articles/2085363.pdf

Data publikacji:

2020

Wydawca:

Instytut Medycyny Wsi

Tematy:

young adults
bioelectrical impedance
phase angle
body composition analyzer
phase angle predictors

Opis:

Introduction and objective. Bioimpedance analysis (BIA) phase angle (PhA) is an index of the integrity of cells and cellular membranes. The aim of the study was identification of behavioural and anthropometric predictors of PhA in a group of young adults. Materials and method. A cross-sectional observational study of health behaviours, anthropometric indicators and body composition assessed by the BIA method was conducted in a group of Polish young adults (n=92) aged 18 – 24 (mean – 19.33, STD – 0.915). Behavioural variables included: level of physical activity, eating behaviours and nutritional knowledge. Body composition was analysed by means of BIA phase-sensitive 8-electrode medical SECA mBCA 525 device. Results. The mean PhA value in the examined cohort was 6.38±0.75 (males – 7.22±0.72; females – 6.13±0.57). Males also showed higher statistically significant other body composition indices, excluding fat mass. The multiple regression model, including anthropometric variables and gender, which explained the effect of these variables on PhA, occurred to be significant (p<0.0000) and allowed explanation of the 82.49% of PhA variability. PhA was significantly predicted from body mass index (BMI), absolute fat mass, visceral adipose tissue value, skeletal muscle mass value and gender. The regression model, including behavioural predictors and gender, allowed explanation of the lower percentage of PhA variability (42.75%; p<0.0000) and included general intensity of health behaviours, level of nutritional knowledge, and gender. A regression model which would consider simultaneously anthropometric and behavioural variables could not be constructed. Conclusions. In the examined cohort, anthropometric and body composition variables showed a stronger predictive value with respect to PhA, compared to behavioural variables.

Źródło:

Annals of Agricultural and Environmental Medicine; 2020, 27, 1; 91-98
1232-1966

Pojawia się w:

Annals of Agricultural and Environmental Medicine

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 19.

Tytuł:

Comparison of contact angle measurement methods of liquids on metal alloys

Autorzy:

Terpiłowski, Konrad
Hołysz, Lucyna
Rymuszka, Diana
Banach, Robert

Powiązania:

https://bibliotekanauki.pl/articles/763967.pdf

Data publikacji:

2016

Wydawca:

Uniwersytet Marii Curie-Skłodowskiej. Wydawnictwo Uniwersytetu Marii Curie-Skłodowskiej

Tematy:

metal alloys
wettability
contact angle

Opis:

The paper presents the studies of metal wettability using two methods: the sessile droplet and immersion ones. Based on the measured contact angles, there was calculated apparent surface free energy from the acidic–basic approach and the contact angle hysteresis. The advancing contact angles measured using the immersion method exhibit a little higher values than those measured by the sessile droplet method. The application of the immersion method leads to obtaining higher contact angle hysteresis. Both methods give different values of contact angles but they can be applied independently for estimation of metal surface wettability.

Źródło:

Annales Universitatis Mariae Curie-Skłodowska, sectio AA – Chemia; 2016, 71, 1
2083-358X

Pojawia się w:

Annales Universitatis Mariae Curie-Skłodowska, sectio AA – Chemia

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 20.

Tytuł:

Korzyści wynikające z udziału w projektach badawczych w metrologii– EMRP SIB 58 ANGLE
The benefits of participation in research projects in metrology– EMRP SIB 58 ANGLE

Autorzy:

Przybylska, Joanna

Powiązania:

https://bibliotekanauki.pl/articles/952578.pdf

Data publikacji:

2017

Wydawca:

Główny Urząd Miar

Tematy:

projekty badawcze
metrologia
pomiar kąta
autokolimator
research projects
metrology
angle measurements
autocollimator

Opis:

Precyzyjne pomiary kąta płaskiego znajdują zastosowanie m.in. w przemyśle samochodowym, lotniczym i robotyce, a także w kilku zastosowaniach naukowych (np. w pomiarze stałej grawitacji G i kątowej stabilizacji optycznych elementów rentgenowskich). W ramach projektu SIB 58 ANGLE opracowane zostały nowe systemy pomiarowe, urządzenia, nowe metody, zdobyto nową wiedzę i najlepsze praktyki, umożliwiające precyzyjne pomiary kąta płaskiego, zaspokajające rygorystyczne wymagania przemysłu. Zdolności pomiarowe GUM w dziedzinie kąta zostały udoskonalone.
Precise measurements of plane angle have application to automotive or aircraft industry and robotics as well as to several scientific researches (e.g. the measurement of the gravitational constant G and the angular stabilisation of X-ray optical components). In the frame of the project SIB 58 ANGLE new measuring systems, new equipment, new measuring methods were developed, new knowledge and best practices were obtained. It enables high precision angle measurements which meet rigorous industry requirements. The angle measurement capabilities of GUM were improved.

Źródło:

Metrologia i Probiernictwo : biuletyn Głównego Urzędu Miar; 2017, 1-2 (16-17); 18-19
2300-8806

Pojawia się w:

Metrologia i Probiernictwo : biuletyn Głównego Urzędu Miar

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 21.

Tytuł:

Determining the value of surface free energy on the basis of the contact angle

Autorzy:

Kłonica, M.
Kuczmaszewski, J.

Powiązania:

https://bibliotekanauki.pl/articles/102227.pdf

Data publikacji:

2017

Wydawca:

Stowarzyszenie Inżynierów i Techników Mechaników Polskich

Tematy:

energy state
surface layer
contact angle
ozonization

Opis:

This paper presents the results of tests concerning the value of surface free energy on the basis of measurements of contact angle with measure liquids: distilled water and diiodomethane. The surface of steel-316L samples was modified in an ozone atmosphere, and the concentration of ozone and the conditioning time of the samples in the reaction chamber were changed. The results of tests concerning the measurements of the value of surface free energy were subject to analysis. Also analysed were the components of SFE: the polar and dispersive components. The obtained test results were analysed in statistical terms. The paper ends with conclusions.

Źródło:

Advances in Science and Technology. Research Journal; 2017, 11, 1; 66-74
2299-8624

Pojawia się w:

Advances in Science and Technology. Research Journal

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 22.

Tytuł:

Modal characterization of sandwich skew plates

Autorzy:

Pavan-Kumar, Dhotre
Srinivasa, Chikkol V.

Powiązania:

https://bibliotekanauki.pl/articles/2114835.pdf

Data publikacji:

2021

Wydawca:

Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej

Tematy:

natural frequency
non-dimensional frequency parameter
antisymmetric laminate
fiber orientation angle
skew angle

Opis:

The current work focuses on the experimental and finite element free vibration studies of laminated composite sandwich skew plates. The comparison was made between the experimental values obtained by the Fast Fourier transform (FFT) analyzer and a finite el-ement solution obtained from CQUAD8 finite element of The MacNeal-Schwendler Corporation (MSC) / NASA STRucture Analysis (NAS-TRAN) software. The influence of parameters such as aspect ratio (AR) (a/b), skew angle (α), edge condition, laminate stacking sequence, and fiber orientation angle (θ°) on the natural frequencies of sandwich skew plates was studied. The values obtained by both the finite el-ement and experiment approaches are in good agreement. The natural frequencies increase with an increase in the skew angle for all giv-en ARs.

Źródło:

Acta Mechanica et Automatica; 2021, 15, 3; 143--153
1898-4088
2300-5319

Pojawia się w:

Acta Mechanica et Automatica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 23.

Tytuł:

Evaluation of dynamic microscopic advanced angle for droplet on flat surface

Autorzy:

Zapałowicz, Z.

Powiązania:

https://bibliotekanauki.pl/articles/239914.pdf

Data publikacji:

2012

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

dynamika zwilżania
kąt zwilżania
krople
wetting process
wetting angle
liquid microfilm
droplet

Opis:

The paper presents a short description of the model of the phenomenon of droplet spreading in presence of a liquid film, as well as the experimental facility, calculations methodology and results of experimental research concerning determination of the boundary angle at which droplet begins to slide on the horizontal or inclined surface of the plate. Values of boundary angle have been applied to estimate the microscopic dynamic advanced angle of the droplet on the flat surface in presence of a liquid film.

Źródło:

Archives of Thermodynamics; 2012, 33, 2; 107-121
1231-0956
2083-6023

Pojawia się w:

Archives of Thermodynamics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 24.

Tytuł:

Estymacja kąta przechylenia na obiektach ruchomych
Roll angle estimation in moving objects

Autorzy:

Popowski, S.
Dąbrowski, W.

Powiązania:

https://bibliotekanauki.pl/articles/212951.pdf

Data publikacji:

2009

Wydawca:

Sieć Badawcza Łukasiewicz - Instytut Lotnictwa

Tematy:

estymacja kąta przechylenia
obiekty ruchome
roll angle estimation
moving objects

Opis:

W artykule przedstawiono metody pomiaru i estymacji kąta przechylenia, które mogą zostać wykorzystane na różnych obiektach ruchomych. Szczegółowo opisano metody bazujące na pomiarze składowych przyspieszenia grawitacyjnego, metody oparte na wykorzystaniu samokompensującego wahadła giroskopowego, metody oparte na analizie obrazu i promieniowania pod czerwonego, metody oparte na całkowaniu sygnałów giroskopów prędkościowych, metody wykorzystujące wieloantenowy odbiornik GPS i jednoantenowy odbiornik GPS (pseudoorientacja). Opisy wybranych metod pomiarowych zilustrowano doświadczalnymi wynikami uzyskanymi podczas badań laboratoryjnych i na przykładowych obiektach.
This paper presents methods of roll angle measurement and estimation that can be used on several types of moving objects. Several methods are presented in details, e.g. methods based on measurement of acceleration of gravity with gyroscopic pendulum, methods supported by pattern analysis of the view obtained in visible and infra - red radiation, methods estimated by integration of signals produced by angular rate gyroscopes, by multi - antenna GPS receiver and single – antenna GPS receiver (pseudo – attitude). Descriptions of selected measuring methods are illustrated by the experimental results obtained in laboratory tests and on example objects.

Źródło:

Prace Instytutu Lotnictwa; 2009, 7 (202); 88-111
0509-6669
2300-5408

Pojawia się w:

Prace Instytutu Lotnictwa

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 25.

Tytuł:

Dihedral angle of the regular a-simplex

Autorzy:

Krasnodębski, R.

Powiązania:

https://bibliotekanauki.pl/articles/963407.pdf

Data publikacji:

1971

Wydawca:

Polskie Towarzystwo Matematyczne

Opis:

The article contains no abstract

Źródło:

Commentationes Mathematicae; 1971, 15, 1
0373-8299

Pojawia się w:

Commentationes Mathematicae

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 26.

Tytuł:

Investigation on silicon solar cell capacitance and its dependence on both temperature and incidence angle

Autorzy:

Sané, M
Barro, F I

Powiązania:

https://bibliotekanauki.pl/articles/102664.pdf

Data publikacji:

2014

Wydawca:

Stowarzyszenie Inżynierów i Techników Mechaników Polskich

Tematy:

vertical junction
capacitance
temperature
incidence angle

Opis:

The aim of this work is to investigate a theoretical study of a vertical junction silicon solar cell capacitance under monochromatic illumination. By solving the continuity equation and using a one dimensional model in frequency modulation, we derive the analytical expressions of both excess minority carrier density and photovoltage. Based on these expressions, the solar cell capacitance was calculated; we then exhibited the effects of both temperature and incidence angle on the solar cell capacitance.

Źródło:

Advances in Science and Technology. Research Journal; 2014, 8, 24; 9-12
2299-8624

Pojawia się w:

Advances in Science and Technology. Research Journal

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 27.

Tytuł:

Vertigo in cerebellopontine angle tumor Patients

Autorzy:

Zarębska-Karpieszuk, Paulina
Bartoszewicz, Robert
Pierchała, Katarzyna
Niemczyk, Kazimierz

Powiązania:

https://bibliotekanauki.pl/articles/1401828.pdf

Data publikacji:

2015

Wydawca:

Index Copernicus International

Tematy:

acoustic neuroma
vestibular schwannoma
vertigo
imbalance;cerebellopontine angle tumor;symptoms T

Opis:

Cerebellopontine angle tumors are a group of tumors that originate from the posterior cranial fossa. Most of them are acoustic neuromas arising from the Schwann cell sheath of the vestibular branch of VIII cranial nerve. Those benign tumors usually present with unilateral hearing loss (53–57%), tinnitus (79–82%), and vertigo/imbalance (18–50%). The objective of this study was documentation-based evaluation of 53 out of 96 patients that received surgical treatment in the ENT Department of Medical University in Warsaw during the period from May 2012 to May 2014, with special consideration of vertigo/imbalance in relation to other symptoms. Statictical analysis has shown larger frequency of vertigo/imbalance in patients with mild to moderate hearing loss and positive corelation between the largest diameter of the tumor and the vestibular deficit in VNG (videonystagmography). The corelation of vestibular deficit in VNG and imbalance symptoms was only estabilished in the group with intrameatal localization of the tumor (T1).

Źródło:

Polski Przegląd Otorynolaryngologiczny; 2015, 4, 4; 27-31
2084-5308
2300-7338

Pojawia się w:

Polski Przegląd Otorynolaryngologiczny

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 28.

Tytuł:

Effective friction angle of deltaic soils in the Vistula Marshlands

Autorzy:

Międlarz, Kamila
Konkol, Jakub
Bałachowski, Lech

Powiązania:

https://bibliotekanauki.pl/articles/178633.pdf

Data publikacji:

2019

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

angle of internal friction
CPTU
triaxial testing
soft soils
peat

Opis:

This article presents the results of laboratory tests on soft, normally consolidated soils from the Vistula Marshlands. Samples of high-plasticity organic soils (muds) taken from 3.2–4.0 m and 9.5–10.0 m depth, as well as peat deposit at 14.0 m, are analysed. Presented case study confirms the applicability of the Norwegian Institute of Technology (NTH) method based on Cone Penetration Tests (CPTU) and allows for a conservative estimation of effective friction angle for muds. The plastification angle equal to 14.5° for organic silt, applied in the modified NTH method, fits well the triaxial test (TX) results. Moreover, the dilative-contractive behaviour according to the CPTU soil classification based on the Robertson’s proposal from 2016 corresponds well with volumetric changes observed in the consolidated drained triaxial compression tests. The internal friction angles of the Vistula Marshlands' muds and peats are lower in comparison with the database of similar soft soils.

Źródło:

Studia Geotechnica et Mechanica; 2019, 41, 3; 143-150
0137-6365
2083-831X

Pojawia się w:

Studia Geotechnica et Mechanica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 29.

Tytuł:

Problemy pomiaru kąta przechylenia na obiektach ruchomych
Problems of measuring the roll angle on moving objects

Autorzy:

Gałach, A.
Dąbrowski, W.

Powiązania:

https://bibliotekanauki.pl/articles/275341.pdf

Data publikacji:

2010

Wydawca:

Sieć Badawcza Łukasiewicz - Przemysłowy Instytut Automatyki i Pomiarów

Tematy:

pomiary kąta przechylenia
roll angle measurement

Opis:

W artykule przedstawiono metody pomiaru i estymacji kąta przechylenia na obiektach mobilnych. Przedstawiono wybrane metody pomiaru kąta przechylenia oraz opisano sposób integracji tych pomiarów. Opis metod pomiarowych zilustrowano doświadczalnymi wynikami uzyskanymi podczas badań laboratoryjnych i na wybranych obiektach.
The paper presents the methods of roll angle measurement and estimation on moving objects. The article describes selected methods of roll angle measurement as well as the algorithms of measurements integration. Discussed methods are illustrated with experimental results obtained in laboratory and during tests on selected objects.

Źródło:

Pomiary Automatyka Robotyka; 2010, 14, 2; 722-731
1427-9126

Pojawia się w:

Pomiary Automatyka Robotyka

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 30.

Tytuł:

Parametrization of Cauchy stress tensor treated as autonomous object using isotropy angle and skewness angle

Autorzy:

Ziółkowski, Andrzej

Powiązania:

https://bibliotekanauki.pl/articles/38887565.pdf

Data publikacji:

2022

Wydawca:

Instytut Podstawowych Problemów Techniki PAN

Tematy:

Cauchy stress
oriented geometrical object
isotropy angle
skewness angle
isomorphic cylindrical coordinates
pure shear
comparison reference state
anisotropy factor
biaxial tests
simple shear
planar shear
triaxiality factor

Opis:

Intrinsic features (eigenproperties) of the Cauchy stress tensor are discussed. Novelty notions of isotropy and skewness mode angles are introduced for the improved parametric description of spherical (isotropic) and deviatoric (anisotropic) components of stress tensor. The skewness angle is defined with pure shear employed as a comparison reference mode upon observing that pure shear states can be interpreted as elementary (atomic) blocks of any macroscopic deviatoric stress state. An original statistical-physical interpretation of the stress tensor orthogonal invariants is provided. A micromechanical explanation for observed decrease of the stress tensor anisotropy factor values, measured in terms of the tensor orbit diameter, with stress deviator diverging from pure shear mode, is proposed. Explicit reasons explaining why biaxial experimental layouts (simple shear and/or planar shear) are insufficient for the comprehensive characterization of materials properties submitted to complex stress states loadings are presented. New explicit formulas for the triaxiality factor valid for biaxial stress states are delivered.

Źródło:

Engineering Transactions; 2022, 70, 3; 239-286
0867-888X

Pojawia się w:

Engineering Transactions

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 31.

Tytuł:

Theoretical Model of the Influence of Textile Structure on Wetting Hysteresis
Model teoretyczny wpływu struktury tkaniny na jej histerezę zwilżania

Autorzy:

Bachurová, M.
Wiener, J.

Powiązania:

https://bibliotekanauki.pl/articles/234300.pdf

Data publikacji:

2013

Wydawca:

Sieć Badawcza Łukasiewicz - Instytut Biopolimerów i Włókien Chemicznych

Tematy:

real contact angle
apparent contact angle
contact angle hysteresis
textile structure
rzeczywisty kąt zwilżania
pozorny kąt zwilżania
histereza zwilżania
struktura tkaniny

Opis:

In our work we theoretically analysed the influence of textile structure on the hysteresis of wetting. The situation with current fabrics is complicated and the properties of fibers, yarns, and geometric arrangement also influence their wetting. The basis of the theoretical model is a simple plain weave fabric made from monofilaments. From this model we determined the real contact angle and apparent contact angle, and later we compared these values with results from the experimental measurement.
W pracy przeanalizowano pod względem teoretycznym wpływ struktury tkaniny na histerezę zwilżania. Właściwości włókien, przędz i układ geometryczny mają wpływ na zwilżanie tkanin. Podstawą modelu teoretycznego jest tkanina o splocie prostym wykonana z monofilamentów. Wyznaczono rzeczywisty i pozorny kąt zwilżania, a następnie porównano otrzymane wartości z wynikami pomiarów eksperymentalnych.

Źródło:

Fibres & Textiles in Eastern Europe; 2013, 2 (98); 80-83
1230-3666
2300-7354

Pojawia się w:

Fibres & Textiles in Eastern Europe

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 32.

Tytuł:

Effect of exit blade angle, viscosity and roughness in centrifugal pumps investigated by CFD computation

Autorzy:

Li, W.

Powiązania:

https://bibliotekanauki.pl/articles/1934039.pdf

Data publikacji:

2011

Wydawca:

Politechnika Gdańska

Tematy:

centrifugal pump
impeller
volute
viscosity
performance
blade angle
viscous oil

Opis:

It has long been known that the exit blade angle plays a very important role in the performance of a centrifugal pump handling water or viscous oil. The effect of exit blade angle on the performance and flow of centrifugal pumps is usually investigated experimentally. However, due to the high cost and limited data that can be obtained by experiment, currently there is a great need for this effect to be studied numerically by means of computational fluid dynamics (CFD). At present, extensive comparisons between experiment and simulation regarding the performance of viscous oil and flow in centrifugal pumps with different exit blade angles are not available. Hydraulic performance and flow details in the impeller and the volute of a centrifugal pump with an exit blade angle of 44o were investigated numerically with the CFD code Fluent, using water and viscous oil as the working fluid, respectively. The effect of exit blade angle was then elucidated by comparing the performance and flow with that of a pump with an exit blade angle of 20o. It was determined that the results for the performance and flow obtained by means of CFD were in qualitative agreement with the observations. The sudden-rising-head effect is dependent on roughness and viscosity. The unstable zone in the theoretical head curve of the impeller at a low flow rate was attributed to the strong reaction of the volute to the flow in the vicinity of the impeller exit. The flow in the impeller with a large exit blade angle was subject to separation near the blade pressure side, however, a large exit blade angle helped improve the pump performance of viscous oil.

Źródło:

TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2011, 15, 1; 21-41
1428-6394

Pojawia się w:

TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 33.

Tytuł:

Any-angle Global Path Planning for Skid-Steered Mobile Robots on Heterogeneous Terrain

Autorzy:

Jaroszek, P.

Powiązania:

https://bibliotekanauki.pl/articles/384522.pdf

Data publikacji:

2016

Wydawca:

Sieć Badawcza Łukasiewicz - Przemysłowy Instytut Automatyki i Pomiarów

Tematy:

spath planning
skid-steered mobile robot
Theta*
any-angle path planning
A*

Opis:

The paper is concerned with selection of the algorithm of path planning for a skid-steered mobile robot operating on heterogeneous terrain. Methods of path searching were reviewed and their applicability to particular kinematic structure of a robot was assessed. The Theta* graph search algorithm was selected, because of its property of returning any-angle paths. Because in this method variable terrain type is not considered, necessary changes in algorithm structure were proposed to check homogeneity of the terrain. In order to enable choice of arbitrary optimization criterion, the model of cost dependent on terrain properties was introduced, which includes both longitudinal motion and turning. Operation of the modified algorithm with the introduced cost model was verified by means of simulation against A* reference algorithm often used in path planning tasks.

Źródło:

Journal of Automation Mobile Robotics and Intelligent Systems; 2016, 10, 2; 50-56
1897-8649
2080-2145

Pojawia się w:

Journal of Automation Mobile Robotics and Intelligent Systems

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 34.

Tytuł:

Effect of the narrowing angle in beveliod gear on the temperature profile on the active flank of tooth

Autorzy:

Sobolak, M.
Strojny, P.

Powiązania:

https://bibliotekanauki.pl/articles/103208.pdf

Data publikacji:

2013

Wydawca:

Stowarzyszenie Inżynierów i Techników Mechaników Polskich

Tematy:

Beveloid gear
temperature profile
narrowing angle

Opis:

This paper contains a description of the test bench to research the temperature distribution in gears made of a plastic polymer. The paper presents the research results of the change and the temperature distribution on the side surface of the Beveloid tooth gear. The research were performed for a series of Beveloid gears with different values of narrowing angle.

Źródło:

Advances in Science and Technology. Research Journal; 2013, 7, 20; 67-69
2299-8624

Pojawia się w:

Advances in Science and Technology. Research Journal

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 35.

Tytuł:

A research model of a ship’s angle of heel

Autorzy:

Mironiuk, W.

Powiązania:

https://bibliotekanauki.pl/articles/135242.pdf

Data publikacji:

2016

Wydawca:

Akademia Morska w Szczecinie. Wydawnictwo AMSz

Tematy:

maritime transport
ship stability
righting lever
heeling moment
dynamic stability arm
angle of heel
ship rolling

Opis:

According to some authors it is estimated that around 80% of accidents at sea are caused by human and organizational errors (HOE). In order to gain knowledge of phenomena that occur during ship operations, a decision was made to design and build a test site for carrying out model-based investigations of ships, including in situations of hazard to buoyancy. The model-based investigations are used as the basic and universal method for forecasting ship dynamic properties. The results of initial research on the dynamic impact of air flow on an 888 project type ship model are presented in the elaboration. The research has been executed at a test stand located in the Polish Naval Academy. The experimental results have been compared with theoretical calculations for angle of dynamic heel. Input parameters for the tests and calculations have been defined in accordance with recommendations of the Polish Register of Shipping (PRS) and International Maritime Organization (IMO) (IMO Instruments).

Źródło:

Zeszyty Naukowe Akademii Morskiej w Szczecinie; 2016, 46 (118); 43-48
1733-8670
2392-0378

Pojawia się w:

Zeszyty Naukowe Akademii Morskiej w Szczecinie

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 36.

Tytuł:

The influence of camelina oil ester additive to diesel fuel on self - ignition angle in agricultural engine

Autorzy:

Orliński, P.

Powiązania:

https://bibliotekanauki.pl/articles/241585.pdf

Data publikacji:

2013

Wydawca:

Instytut Techniczny Wojsk Lotniczych

Tematy:

camelina oil ester
self-ignition delay angle
diesel engine

Opis:

The article presents the results of investigations referring to self-ignition delay angle determined experimentally and through simulations. It was done using charged agricultural Perkins 1104C-E44T engine powered by pure diesel fuel (ON) and fuel mixtures, such as: diesel fuel with 10% camelina oil ester additive (L10) and diesel fuel with 15% camelina oil ester additive (L15). Camelina oil ester was used to show that it can also be used as an additive plant to diesel fuel (according to the plans of the European Union). Similarly to on a large scale used ester of rapeseed oil. The main aim of the above mentioned research was to show the influence of the fuels on the change of self-ignition delay angle for different rotational velocity conditions of the engine and for maximum volumetric dose of ignited fuel. The research was performed using a dynamometer test stand equipped with measurement system of fast-changeable needle lift of injector and the pressures of working substance. Before starting the investigations, selected physicochemical properties of researched fuels were determined that significantly influence that parameter of the combustion process. At the end of the article the conclusion of experiments and simulations results referring to selfignition delay angle are analysed.

Źródło:

Journal of KONES; 2013, 20, 2; 323-328
1231-4005
2354-0133

Pojawia się w:

Journal of KONES

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 37.

Tytuł:

Najnowsze kierunki rozwoju metrologii kąta płaskiego
New frontiers in angle metrology

Autorzy:

Nicińska, K.
Przybylska, J.

Powiązania:

https://bibliotekanauki.pl/articles/267373.pdf

Data publikacji:

2017

Wydawca:

Politechnika Gdańska. Wydział Elektrotechniki i Automatyki

Tematy:

kąt płaski
enkoder kątowy
autokolimator
projekt EMRP
plane angle
encoders
autocollimator
project EMRP

Opis:

Artykuł opisuje w skrócie najważniejsze efekty prac wspólnego projektu EMRP SIB 58 Angles „Angle Metrology”, w którym Główny Urząd Miar brał udział w latach 2013-2016. W ramach tego projektu zostały opracowane i przebadane: stanowiska pomiarowe pozwalające na pomiar 2D autokolimatorów fotoelektrycznych, generatory małych kątów, urządzenie do odtwarzalnego pozycjonowania przesłon w stosunku do osi autokolimatora. Przetestowana została również nowa metoda pomiarowa jednoczesnego wyznaczania wartości błędów pomiaru stołu obrotowego i autokolimatora fotoelektrycznego. Opracowano także uniwersalne przewodniki techniczne EURAMET dotyczące wzorcowania autokolimatorów fotoelektrycznych i precyzyjnych enkoderów kątowych. W artykule opisano również doświadczenie, jakie Laboratorium Długości zdobyło podczas prac nad projektem.
The article describes in short the most important results of the investigations carrying out in the frame of Joint Project EMRP SIB 58 Angles “Angle Metrology”. Central Office of Measures participated in this project in years 2013 – 2016. The new small angle generators, the new systems for 2D calibration of autocollimators, the new device for reproducible positioning of the aperture relative to the autocollimator optical axis, the new method for simultaneously calibration of autocollimators and angle encoders (“shearing techniques”) were developed and tested. Additionally the investigations on the autocollimator response on different distances and different diaphragm positions were carried out. Also the influences of not proper mounting and coupling of angle encoders on the indications and uncertainty, during calibration, were mentioned. The special device for these investigations was developed. The EURAMET Technical Guides (Calibration of Autocollimators, Calibration of Angular Encoders) were elaborated and could be downloaded from the website soon. The article presents also profits which Laboratory of Length gained during the project and shortly describes the main tasks, which have to be done to be able to carry out measurements on the level required by customers.

Źródło:

Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej; 2017, 54; 163-166
1425-5766
2353-1290

Pojawia się w:

Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 38.

Tytuł:

An evaluation of the accuracy of inverter sync angle during the grids disturbances

Autorzy:

Jarzyna, Wojciech
Zieliński, Dariusz
Gopakumar, K.

Powiązania:

https://bibliotekanauki.pl/articles/221529.pdf

Data publikacji:

2020

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

inverter synchronization
synchronization angle
PLL
sync error
distributed grid

Opis:

The grid-tied inverter synchronizes with the network on the basis of the instantaneous voltage phase angle. This angle is computed by the so-called synchronization algorithms. During grid disturbances, it is estimated with a certain accuracy, which varies for different disturbances and depends on the choice of algorithm. The tests presented here determine how to make an optimal selection of the synchronization algorithm. The research methods used are modeling, simulation and analysis of the results obtained. One of the most important outcomes is the determination of the root-mean-square sync error and its dynamics denotation. The research conclusions should be of particular interest to designers of distributed energy systems with a large number of inverter energy sources.

Źródło:

Metrology and Measurement Systems; 2020, 27, 2; 355-371
0860-8229

Pojawia się w:

Metrology and Measurement Systems

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 39.

Tytuł:

The analysis of the solar power plant performance in temperate climate

Autorzy:

Zdyb, A.
Dragan, P.
Jaremek, A.

Powiązania:

https://bibliotekanauki.pl/articles/105126.pdf

Data publikacji:

2018

Wydawca:

Politechnika Rzeszowska im. Ignacego Łukasiewicza. Oficyna Wydawnicza

Tematy:

photovoltaics
grid connected solar plant
photovoltaic performance
inclination angle
tilt angle

Opis:

Due to gradual depletion of fossil fuels resources and emission of harmful chemicals accompanying the combustion process, the interest in alternative energy sources still increases. Among many kinds of alternative sources, solar radiation is very special because of its wide availability and large technical potential. Photovoltaic systems providing the electric energy are used in many countries. The most important part of photovoltaic system is a module, which parameters (e.g. efficiency, rated power, temperature coefficients of power and efficiency, short circuit current, open circuit voltage) are determined in laboratory tests under Standard Test Conditions (STC: 25°C, 1,000 W/m2 , air mass 1.5). However, in real outdoor conditions the modules exhibit lower efficiency since local climate influences their performance and different external factors generate energy losses in the whole system. The aim of this work is the performance analysis of a solar power plant connected to the grid, which total rated power is 2.985 MW and it works in temperate climate in eastern Poland. Insolation in the location was estimated according to Solargis data and the role of the modules tilt angle, of which the value is non-typical for the considered location was studied. The tilt angle smaller than optimal angle allows increasing the amount of the solar radiation collected in the summer period. The electric energy production based on the inverters data in 2016 and 2017 as well as yearly yield are presented. The results are compared to data coming from other solar power plants, also located at high latitude.

Źródło:

Czasopismo Inżynierii Lądowej, Środowiska i Architektury; 2018, 65, 1; 73-79
2300-5130
2300-8903

Pojawia się w:

Czasopismo Inżynierii Lądowej, Środowiska i Architektury

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 40.

Tytuł:

Algorithmic method for phase angle shift of noisy voltages using conditional averaging of delayed signals absolute value

Autorzy:

Kowalczyk, A.
Szlachta, A.

Powiązania:

https://bibliotekanauki.pl/articles/221009.pdf

Data publikacji:

2011

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

phase angle shift
additive disturbance
conditional signal averaging

Opis:

The method of a phase shift angle measurement using conditional averaging of delayed signal absolute value (CAAV) is presented in this paper. The input sinusoidal signal x(t) is without noise. White noise with normal distribution and band limited to low frequencies has been applied as disturbance of delayed sinusoidal signal z(t). Noise n(t) - N(0, δn) is added to the delayed signal - the noised and delayed signal z(t) is obtained. The phase angle shift is proportional to time location of CAAV's minimum (minimum of the characteristic of conditional averaging of delayed signal's absolute value). The phase angle shift can be determined on the basis of conditional averaging value of elaborated algorithm. The characteristics of conditional average of delayed signal's absolute value in the surrounding of the minimum of this function (the results of practical investigations and theoretical calculation) are presented. The experimental variance of characteristic CAAV in surroundings of the minimum (obtained from practical investigations and calculation) is illustrated in the paper. The algorithms of conditional averaging have been elaborated and practically realized in the LabVIEW environment.

Źródło:

Metrology and Measurement Systems; 2011, 18, 1; 137-144
0860-8229

Pojawia się w:

Metrology and Measurement Systems

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 41.

Tytuł:

The riddle of phyllotaxis: exquisite control of divergence angle

Autorzy:

Okabe, T.

Powiązania:

https://bibliotekanauki.pl/articles/57698.pdf

Data publikacji:

2016

Wydawca:

Polskie Towarzystwo Botaniczne

Opis:

Phyllotaxis studies published in German in the 1930s have reported intriguing regularity in the arrangement of incipient leaves on shoot apices of a wide variety of plant species. However, these studies have received little attention today, even though they provide a crucial evidence base for understanding this mathematical phenomena. Here I recapitulate the essential point by means of illustrative examples. It is emphasized that accurate control of apical divergence angle is at the heart of the numerical riddle of spiral phyllotaxis. The accurate patterning at the shoot apex has an unexpected evolutionary benefit of being optimally adaptive in the subsequent events of phyllotactic change to occur on an elongating shoot.

Źródło:

Acta Societatis Botanicorum Poloniae; 2016, 85, 4
0001-6977
2083-9480

Pojawia się w:

Acta Societatis Botanicorum Poloniae

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 42.

Tytuł:

The effect of angle of attack on the generated wave propagation

Autorzy:

Javanmardi, M.
Binns, J.
Izham, M. I. C.
Rafieshahraki, J.

Powiązania:

https://bibliotekanauki.pl/articles/135352.pdf

Data publikacji:

2017

Wydawca:

Akademia Morska w Szczecinie. Wydawnictwo AMSz

Tematy:

wave propagation
surfable wave
wave quality
angle of attack

Opis:

The presented work is an experimental investigation into the waves generated by a pressure source moving in a straight channel. Wave fields generated by the moving pressure source are described and the effects of angle of attack on the generated wave height, surfable wave quality, drag and vertical forces are presented. The main objective of this study was to investigate the relationship between the angle of attack and the generated wave height across the towing tank width and the surfable wave quality. The investigations were conducted at the Australian Maritime College towing tank on a wavedozer at four different attack angles at various speeds. Three wave probes were installed across the channel to record the generated wave heights. Based on the experimental results, it was concluded that smaller angles of attack produced higher quality surfable waves compared to larger angles of attack, while the height of the generated wave has a direct relationship with the angle of attack. By comparing the forces for different models, it was concluded that the pressure source with the lowest angle of attack has the minimum drag but maximum displacement.

Źródło:

Zeszyty Naukowe Akademii Morskiej w Szczecinie; 2017, 50 (122); 36-41
1733-8670
2392-0378

Pojawia się w:

Zeszyty Naukowe Akademii Morskiej w Szczecinie

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 43.

Tytuł:

A Characterization of Ultrasonic Full Angle Spatial Compounding as a Possible Alternative for Breast Cancer Screening

Autorzy:

Medina, L.
Camacho, J.
Fritsch, C.

Powiązania:

https://bibliotekanauki.pl/articles/177766.pdf

Data publikacji:

2015

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

breast cancer
Full Angle Spatial Compounding
resolution
isotropy

Opis:

Breast cancer screening is based on X-ray mammography, while ultrasound is considered a complementary technique with improved detection in dense tissue. However, breast cancer screening requires a technique that provides repeatable results at the inspection interval which cannot be achieved with manual breast exploration. During the last years there have appeared several approaches to overcome this limitation by means of automated ultrasonic tomography performed with motorized probes or with a large set of array transducers. This work addresses these problems by considering a quite simple and low-cost arrangement, formed with a ring of conventional medical-grade array probes which are multiplexed to the electronics to build Full Angle Spatially Compounded (FASC) images. The work analyzes the performance of such arrangement in terms of resolution and isotropy, showing by numerical modelling and experimentally that it provides high resolution and homogeneity in the whole imaged region. The implementation of this technique would provide more than one circular FASC per second and a whole breast volume image in 1–2 minutes with conventional technology, a process fast enough to be clinically useful. Moreover, the automated technique is repeatable and can be used by the clinician to perform immediately the diagnosis without requiring additional data processing.

Źródło:

Archives of Acoustics; 2015, 40, 3; 301-310
0137-5075

Pojawia się w:

Archives of Acoustics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 44.

Tytuł:

Evaluation of fouling potential of nanofiltration membranes based on the dynamic contact angle measurements

Autorzy:

Gryta, M.
Bastrzyk, J.
Lech, D.

Powiązania:

https://bibliotekanauki.pl/articles/779112.pdf

Data publikacji:

2012

Wydawca:

Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie

Tematy:

nanofiltration
dynamic contact angle
fouling
Wilhelmy plate method
glycerol fermentation

Opis:

In this work the studies were performed on the intensity of fouling of the membrane NF90 and NF270 depending on the value of dynamic contact angle, previously determined for these membrane. The NF membranes were used for the separation of broth obtained during the fermentation of glycerol by Lactobacilluscasei bacteria. The measurements of dynamic contact angle were carried out using the Wilhelmy plate method. Taped membranes samples (support layer to support layer), wetted for 2 days in deionized water prior to testing, were used to study the contact angle of top layer and its organic fouling. Using deionized water; the contact angle values equal to 27-30o and 53-57o for NF270 and NF90, respectively, were obtained. As a consequence of adsorption of organic compound on the membrane surfaces, the contact angle obtained for both fouled membranes was about 55-56o, and this value was closer to the contact angle of non-fouled NF90 membrane. Therefore, the NF90 membrane was more resistant to organic fouling during the separation of broth.

Źródło:

Polish Journal of Chemical Technology; 2012, 14, 3; 97-104
1509-8117
1899-4741

Pojawia się w:

Polish Journal of Chemical Technology

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 45.

Tytuł:

The suitability of angle measurements made with steep targets for determining spatial positions of points

Autorzy:

Odziemczyk, W.

Powiązania:

https://bibliotekanauki.pl/articles/224458.pdf

Data publikacji:

2007

Wydawca:

Politechnika Warszawska. Wydział Geodezji i Kartografii

Tematy:

teodolit prezyzyjny
tachymetr
pomiary geodezyjne
precise theodolites
geodesic measurements
angle measurements
engineering surveying

Źródło:

Reports on Geodesy; 2007, z. 1/82; 217-223
0867-3179

Pojawia się w:

Reports on Geodesy

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 46.

Tytuł:

The relationship of breaststroke training on knee pain and q angle of breaststroke and crawl swimmers

Autorzy:

Hefzollesan, Mehrdad
Tofighi, Asghar
Qarakhanlou Jamali, Bahram
Ghalehgir, Sohrab

Powiązania:

https://bibliotekanauki.pl/articles/1054834.pdf

Data publikacji:

2014

Wydawca:

Uniwersytet Szczeciński. Wydawnictwo Naukowe Uniwersytetu Szczecińskiego

Tematy:

Q angle
universal goniometry
whip kick

Opis:

Competitive swimmers have a high incidence of breaststroke-related knee injuries. The cause of the breaststroke swimmer’s knee, which is accompanied with medial pain of the knee joint, has not been clearly identified. The purpose of this investigation was to determine the biomechanical and anatomical factors which predispose subjects to injury. This study includes 60 breaststroke and crawl swimmers (16 ±3.2 years old) who have participated in 3–6-year-long swimming training in Tabriz city. The knee pain was evaluated with McGill’s pain questionnaire, and Q angle was measured with universal goniometry by knee radiography in standing position. The medial pain of knee joint increased significantly and the knee was only symptomatic when the swimmers performed the whip kick. Breaststroke swimmers were hardly able to complete training because of the knee pain. It is concluded that competitive training of breaststroke swimming for 6 months can cause exclusive injury and pain in swimmer’s knee. On the other hand, the result showed that there is a direct relationship between the swimmer’s Q angle amount and chance of the knee injury. This emphasizes a scrious consideration of Q angle states in breaststroke swimmers.

Źródło:

Central European Journal of Sport Sciences and Medicine; 2014, 7, 3; 29-36
2300-9705
2353-2807

Pojawia się w:

Central European Journal of Sport Sciences and Medicine

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 47.

Tytuł:

Experimental study of precision angle encoder

Autorzy:

Uvarovas, Povilas
Kavaliauskas, Vilius
Kilikevičienė, Kristina
Kilikevičius, Artūras
Svilainis, Paulius
Matijošius, Jonas
Więckowski, Dariusz

Powiązania:

https://bibliotekanauki.pl/articles/1838330.pdf

Data publikacji:

2020

Wydawca:

Sieć Badawcza Łukasiewicz. Przemysłowy Instytut Motoryzacji

Tematy:

precision encoder
measuring system
dynamic characteristics
angle encoder
shock
harmonic excitation

Opis:

The application of new and advanced production processes plays an important role in the development of the manufacturing industry. This trend is especially relevant to the automotive industry, where each element must ensure high quality requirements. Therefore, automating the automotive manufacturing process is necessary to ensure the highest level of control methods. For this purpose, various sensors are used, the signals of which are analyzed and the control plan itself is adjusted. Experimental investigations of a precision angle encoder were performed in the work. During the research, the dynamic characteristics of the created stand were determined. Experimental studies yielded the results of an experimental study of a precision angle encoder when the system is subjected to shock and harmonic excitation. In order to elucidate the effect of oscillations on the accuracy of a high-resolution coded precision angle encoder, primary electrical signals and their change under oscillations were recorded. Studies have shown that highresolution code-precision angle encoders have different design responses to dynamic effects depending on the direction of the vibrations acting.

Źródło:

Archiwum Motoryzacji; 2020, 90, 4; 5-14
1234-754X
2084-476X

Pojawia się w:

Archiwum Motoryzacji

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 48.

Tytuł:

The analysis of influence of fuel spray angle on NOx fraction in the exhaust gas from marine 4-stroke diesel engine

Autorzy:

Kowalski, J.

Powiązania:

https://bibliotekanauki.pl/articles/246120.pdf

Data publikacji:

2015

Wydawca:

Instytut Techniczny Wojsk Lotniczych

Tematy:

marine diesel engine
NOx fraction
spray angle
CFD model

Opis:

The manuscript presents the analysis of influence of fuel spray angle on NOx fraction in the exhaust gas emitted from marine 4-stroke diesel engine. Analysis is based on computational fluid dynamic (CFD) model designed because of the motion mesh of combustion chamber of the marine engine cylinder and air inlet and exhaust gas ducts. Presented model consists of models of fuel injection into combustion chamber, breaking-up and evaporation of the fuel, mixing with air and turbulent combustion with heat transfer to construction elements of the engine cylinder. Mentioned CFD model is validated according to boundary and initial conditions taken from direct measurements. The chosen research object is laboratory 4-stroke turbocharged Diesel engine with direct injection of the fuel and mechanically controlled of both cylinder valves and the injector. The conclusion from the analysis is that the increase of fuel spray angle causes the increase of maximum speed of kinetic phase of the combustion and the decrease of maximum speed of diffusion phase of the combustion. The effect of this is the increase of maximum combustion pressure and the decrease of maximum combustion temperature. The result of presented changes in combustion process is the increase of NOx fraction in the exhaust gas. It should be noted that extended increase of the fuel spray angle cause close-up the fuel spray to the cylinder heads wall and the decrease of NOx fraction in the exhaust gas.

Źródło:

Journal of KONES; 2015, 22, 3; 309-316
1231-4005
2354-0133

Pojawia się w:

Journal of KONES

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 49.

Tytuł:

Badania kąta przesunięcia elektrycznego dla próbek piasku i bentonitu
Analysis of angle of electric phase displacement for sand and bentonite samples

Autorzy:

Krochmal, J. K.

Powiązania:

https://bibliotekanauki.pl/articles/300503.pdf

Data publikacji:

2010

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

kąt przesunięcia elektrycznego
angle of electric phase displacement

Opis:

W Laboratorium Katedry Inżynierii Naftowej Wydziału Wiertnictwa, Nafty i Gazu AGH wykonano prototypowe stanowisko badawcze oparte na nowoczesnym mierniku impedancji firmy Hioki typu 3522, na którym zgodnie z realizacją projektu badawczego N524 348335 wykonano testowe badania kąta fazowego phi modelowych próbek piasku drobnoziarnistego i bentonitu, w zakresie częstotliwości dostępnej tym miernikiem od 0,001 Hz do 100 kHz, w warunkach powietrzno-suchych. Ośrodki te charakteryzują się różnymi zdolnościami sorpcji wody, która jako składnik silnie polarny wpływa na polaryzację elektryczną. Wyniki tych badań potwierdzają przewidywane, na podstawie wcześniejszych badań, istotnie różne wartości częstotliwości odpowiadające obserwowanej maksymalnej wartości kąta j dla piasku drobnoziarnistego i bentonitu.
A prototype research stand based on modern impedance meter Hioki 3522 type was made in the Laboratory of Oil Engineering, Faculty of Drilling, Oil and Gas, AGH-UST. It was used for realization of a research project no. N524 348335 within which phase angle j of modeled fine sand and bentonite samples was tested for frequencies available with the meter, i.e. 0.001 Hz to 100 kHz in air-dry conditions. These media have different water sorption qualities; being strongly polar, water influences electrical polarization. The results of these experiments confirm results expected on the basis of previous tests. Significant differences were revealed between frequencies corresponding to the observed maximum value of angle j for fine sand and bentonite.

Źródło:

Wiertnictwo, Nafta, Gaz; 2010, 27, 1--2; 225-229
1507-0042

Pojawia się w:

Wiertnictwo, Nafta, Gaz

Dostawca treści:

Biblioteka Nauki

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Tytuł:

Experimental study of precision angle encoder

Autorzy:

Uvarovas, Povilas
Kavaliauskas, Vilius
Kilikevičienė, Kristina
Kilikevičius, Artūras
Svilainis, Paulius
Matijošius, Jonas
Więckowski, Dariusz

Powiązania:

https://bibliotekanauki.pl/articles/1838321.pdf

Data publikacji:

2020

Wydawca:

Sieć Badawcza Łukasiewicz. Przemysłowy Instytut Motoryzacji

Tematy:

precision encoder
measuring system
dynamic characteristics
angle encoder
shock excitation
harmonic excitation

Opis:

The application of new and advanced production processes plays an important role in the development of the manufacturing industry. This trend is especially relevant to the automotive industry, where each element must ensure high quality requirements. Therefore, automating the automotive manufacturing process is necessary to ensure the highest level of control methods. For this purpose, various sensors are used, the signals of which are analyzed and the control plan itself is adjusted. Experimental investigations of a precision angle encoder were performed in the work. During the research, the dynamic characteristics of the created stand were determined. Experimental studies yielded the results of an experimental study of a precision angle encoder when the system is subjected to shock and harmonic excitation. In order to elucidate the effect of oscillations on the accuracy of a high-resolution coded precision angle encoder, primary electrical signals and their change under oscillations were recorded. Studies have shown that high-resolution code-precision angle encoders have different design responses to dynamic effects depending on the direction of the vibrations acting.

Źródło:

Archiwum Motoryzacji; 2020, 90, 4; 5-14
1234-754X
2084-476X

Pojawia się w:

Archiwum Motoryzacji

Dostawca treści:

Biblioteka Nauki

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