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Wyszukujesz frazę "Yang, J. W." wg kryterium: Autor


Tytuł:
Preventive maintenance strategy optimizing model under two-dimensional warranty policy
Model optymalizacji strategii konserwacji zapobiegawczej w warunkach dwuwymiarowej polityki gwarancyjnej
Autorzy:
Cheng, Z. H.
Yang, Z. Y.
Zhao, J. M.
Wang, Y. B.
Li, Z. W.
Powiązania:
https://bibliotekanauki.pl/articles/302023.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
two-dimensional warranty
imperfect preventive maintenance
availability
gwarancja dwuwymiarowa
niepełna konserwacja zapobiegawcza
dyspozycyjność
Opis:
An effective warranty servicing strategy should be made considering both warranty cost and product availability. Based on the two-dimensional free repair warranty, a strategy combining the imperfect preventive maintenance and minimal repair is proposed where the imperfect preventive maintenances are implemented in a special subregion of the warranty and all other failures are repaired minimally. By modeling the warranty cost and product availability, we derive the optimum warranty servicing strategy and corresponding parameters to minimize the cost-effective of unit time. Finally, we provide a numerical illustration and a comparison with some other strategies.
Efektywna strategia obsługi gwarancyjnej powinna uwzględniać zarówno koszty gwarancji jak i dyspozycyjność produktu. W oparciu o pojęcie dwuwymiarowej gwarancji bezpłatnej naprawy, zaproponowano strategię łączącą niepełną konserwację zapobiegawczą z naprawą minimalną, gdzie działania obsługowe w ramach niepełnej konserwacji zapobiegawczej przeprowadza się w ramach specjalnego podobszaru gwarancji, a wszelkie inne uszkodzenia naprawia się w ramach naprawy minimalnej. Modelując koszty naprawy oraz dyspozycyjność produktu, wyprowadzono optymalną strategię obsługi gwarancyjnej oraz odpowiadające jej parametry w celu zminimalizowania kosztów na jednostkę czasu. Na koniec, proponowane rozwiązanie zilustrowano na przykładzie numerycznym oraz porównano z innymi strategiami
Źródło:
Eksploatacja i Niezawodność; 2015, 17, 3; 365-373
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Theoretical Analysis of the TE Mode Cerenkov Type Second Harmonic Generation in Ion-Implanted X-Cut Lithium Niobate Planar Waveguides
Autorzy:
Du, G.
Li, G.
Zhao, S.
Qiao, W.
Yang, K.
An, J.
Li, M.
Wang, J.
Wang, W.
Powiązania:
https://bibliotekanauki.pl/articles/1808109.pdf
Data publikacji:
2009-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.72.Dd
42.82.Et
Opis:
We present a study of the Cerenkov configuration second harmonic generation in X-cut ion-implanted lithium niobate waveguides. An approximate solution of conversion efficiency is given and plotted which shows that it is very sensitive to the waveguide depth and pump wavelength. The results can be used in the design of waveguides for the efficient second harmonic generation in the Cerenkov configuration.
Źródło:
Acta Physica Polonica A; 2009, 115, 3; 685-689
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Serological and molecular evidence of Coxiella burnetii in samples from humans and animals in China
Autorzy:
El-Mahallawy, H.S.
Kelly, P.
Zhang, J.
Yang, Y.
Wei, L.
Tian, L.
Fan, W.
Zhang, Z.
Wang, C.
Powiązania:
https://bibliotekanauki.pl/articles/49293.pdf
Data publikacji:
2016
Wydawca:
Instytut Medycyny Wsi
Źródło:
Annals of Agricultural and Environmental Medicine; 2016, 23, 1
1232-1966
Pojawia się w:
Annals of Agricultural and Environmental Medicine
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Explanation of the Optical Spectra and Spin-Hamiltonian Parameters for Nickel(II) in Cadmium Bromide Crystal
Autorzy:
Gong, J.
Wang, L.
Feng, W.
Yang, X.
Zhang, F.
Powiązania:
https://bibliotekanauki.pl/articles/1493631.pdf
Data publikacji:
2011-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
71.70.Ch
75.10.Dg
61.72.Bb
76.30.Fc
Opis:
Based on crystal- and ligand-field theory, double-spin-orbital coupling approach was used to analyze the crystal-field energy levels and spin-Hamiltonian parameters of $Ni^{2+}$ ion at trigonal site in $CdBr_2$. The local lattice distortion (Δ R and $τ_{Ni^{2+}}$) is estimated from the crystal field parameters; the crystal field energy Hamiltonian was diagonalized in the full basis consisting of 45 wave functions of the $Ni^{2+}$ ion. Results of calculations are in good agreement with experimental data. The reasonableness of the theoretical results is discussed.
Źródło:
Acta Physica Polonica A; 2011, 120, 3; 497-500
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study on Crystal Structure and Magnetic Properties of Ba4Co2Fe36O60 by Sol-Gel Method
Autorzy:
Jeong, K.-P.
Yang, S.-W.
Kim, J.-G.
Powiązania:
https://bibliotekanauki.pl/articles/351655.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
U-type ferrite
sol-gel method
nano-powder
Opis:
U-type ferrite typified by Ba4Co2Fe36O60 is used as a RAM (Radar Absorbing Materials) in the X-band (8-12 GHz). Ba4Co2Fe36O60 is known to have a complex crystal structure, which makes it difficult to obtain single phase and have low reproducibility. Previously known U-type ferrites have been fabricated based on a ceramic process that mixing (by a ball mill), calcining, grinding, binder mixing, drying, sieving, pressing and sintering. In contrast, the process of preparing the powder by the sol-gel method and its heat-treating is advantageous in that it can reduce the process steps and the required time. In addition, the precise stoichiometric control by the sol-gel method can effectively evaluate the effect of added or substituted elements. In this study investigates the crystal structure of Ba4Co2Fe36O60 synthesized by the sol-gel method and the morphology of U-type ferrite nano-powders according to various heat treatment conditions. Analysis of the crystal structure is used for XRD. Morphology and size are observed by SEM. In addition, VSM is performed to confirm the change of magnetic properties according to various heat treatment conditions.
Źródło:
Archives of Metallurgy and Materials; 2018, 63, 3; 1449-1452
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Luminescence of Highly Excited Nonpolar a-Plane GaN and AlGaN/GaN Multiple Quantum Wells
Autorzy:
Juršėnas, S.
Kuokštis, E.
Miasojedovas, S.
Kurilčik, G.
Žukauskas, A.
Chen, C. Q.
Yang, J. W.
Adivarahan, V.
Asif Khan, M.
Powiązania:
https://bibliotekanauki.pl/articles/2038100.pdf
Data publikacji:
2004-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.55.Cr
73.21.Fg
72.20.Jv
78.47.+p
Opis:
Carrier recombination dynamics in polar and nonpolar GaN epilayers and GaN/AlGaN multiple quantum wells grown over sapphire substrates with various crystallographic orientation were studied under high photoexcitation by 20 ps laser pulses. The transient of luminescence featured a significant enhancement in nonradiative recombination of free carriers for nonpolar a-plane GaN epilayers compared to conventional c-plane samples. The epitaxial lateral overgrowth technique was demonstrated to significantly improve the quality of nonpolar a-plane films. This was proved by more than 40-fold increase in luminescence decay time (430 ps compared to ≤10 ps in the ordinary a-plane epilayer). Under high-excitation regime, a complete screening of built-in electric field by free carriers in multiple quantum wells grown on c-plane and r-plane sapphire substrates was achieved. Under such high excitation, luminescence efficiency and carrier lifetime of multiple quantum wells was shown to be determined by the substrate quality.
Źródło:
Acta Physica Polonica A; 2004, 105, 6; 567-573
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Luminescence of Highly Photoexcited GaN Epilayers and Heterostructures Grown on Different Sapphire Crystal Planes
Autorzy:
Juršėnas, S.
Miasojedovas, S.
Kurilčik, G.
Liuolia, V.
Žukauskas, A.
Chen, C. Q.
Yang, J. W.
Kuokštis, E.
Adivarahan, V.
Asif Khan, M.
Powiązania:
https://bibliotekanauki.pl/articles/2041736.pdf
Data publikacji:
2005-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.55.Cr
73.21.Fg
72.20.Jv
78.47.+p
Opis:
GaN epilayers and AlGaN/GaN multiple quantum wells grown by metalorganic chemical vapor deposition on different crystal planes (c, a, and r) of the sapphire substrate were studied by excitation intensity dependent and time-resolved photoluminescence. In polar multiple quantum wells grown on a- and c-planes, a blueshift of the luminescence band with increasing the excitation energy was observed, indicating that screening of built-in field by free carriers takes place, whereas in nonpolar r-plane grown multiple quantum wells, the luminescence band maintained an almost constant peak position. Full screening of built-in field was achieved at the excitation densities higher than 0.3 mJ/cm$\text{}^{2}$. Under conditions of screened built-in electric field the structures were characterized by carrier lifetime. It was shown that nonpolar multiple quantum wells suffer from high density of nonradiative traps that can be due to substrate related threading dislocations.
Źródło:
Acta Physica Polonica A; 2005, 107, 2; 235-239
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of Loading Time of a Load Plate and Sample Size on the Measurement of Physical Properties of Resilient Materials
Autorzy:
Kim, K.-W.
Yeon, J.-O.
Yang, K.-S.
Kim, M.-J.
Powiązania:
https://bibliotekanauki.pl/articles/178069.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
resilient materials
dynamic stiffness
compressibility
long-term deformation
Opis:
This study investigates several factors that have not been specified in the standard for dynamic stiffness, compressibility, and long-term deformation; these factors can be used to evaluate the acoustic and physical performances of resilient materials. The study is intended to provide basic data for deriving the factors that need to be additionally reviewed through the standards. Since magnitude of dynamic stiffness changes with an increase in loading time, it is necessary to examine the setting of the loading time for a load plate under test conditions. Samples of size 300×300 mm, rather than 200×200 mm, yielded more reliable results for compressibility measurement. Since the test to infer long-term deformation of resilient materials after a period of 10 years in some samples showed variation characteristics different from those specified in the standards, it is recommended that the test method should be reviewed through ongoing research.
Źródło:
Archives of Acoustics; 2015, 40, 2; 159-167
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synthesis, Characterization and Compatibility Studies of Poly(DFAMO/NIMMO) with Propellant and PBX Ingredients
Autorzy:
Li, H.
Yang, Y.
Pan, J.
Wang, W.
Pan, R.
Zhu, W.
Powiązania:
https://bibliotekanauki.pl/articles/358094.pdf
Data publikacji:
2018
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
energetic binder
synthesis
characterization
compatibility
PDN
Opis:
Oxetane-based polymers substituted with difluoroamino groups can be used as energetic binders in propellants and polymer-bonded explosives (PBXs). As a novel candidate, poly(3-difluoroaminomethyl-3-methyloxetane/3-nitratomethyl-3-methyloxetane) (PDN) was synthesized and its structure was established. Thermogravimetry (TG) and differential scanning calorimetry (DSC) were employed to investigate its thermal decomposition behaviour. The compatibility between PDN and some common ingredients of propellants and PBXs was evaluated by the DSC method. PDN with good thermal stability was synthesized via a cationic solution polymerization process. Additionally, it has improved compatibility with cyclotetramethylenetetranitramine (HMX), carbon black (C.B.) and lead carbonate (PbCO3) compared with homopoly(3-difluoroaminomethyl-3-methyloxetane) (PDFAMO). PDN could be used as a promising difluoroamino energetic binder in the future.
Źródło:
Central European Journal of Energetic Materials; 2018, 15, 1; 85-99
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluation of the Manufacturing and Functions of Complex Yarn and Fabrics
Wpływ geometrycznych parametrów strukturalnych przędz fantazyjnych na ich właściwości wytrzymałościowe
Autorzy:
Lin, C. M.
Lin, C. W.
Yang, Y. C.
Lou, C. W.
Chen, A. P.
Lin, J. H.
Powiązania:
https://bibliotekanauki.pl/articles/232604.pdf
Data publikacji:
2012
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Biopolimerów i Włókien Chemicznych
Tematy:
siła
ocena
funkcjonalny
elastyczny
właściwości wytrzmałościowe
konstrukcja
rozwój
strength
strain
evaluation
elastic
functional
characterization
design
development
Opis:
In this research, bamboo charcoal/spandex (BC/S) complex yarn was fabricated using spandex as the core yarn, which was then wrapped with bamboo charcoal nylon textured yarn. The core yarn was first expanded and then wrapped with the wrapping yarn on a rotor twister machine at speeds of 4000, 6000, 8000, 10000, and 12000 r.p.m. The wrapping amount of the BC/S complex yarns were 2, 3, and 4 turns/cm. In order to evaluate the physical properties of the BC/S complex yarn, the maximum breaking strength, elongation, and elastic recovery rate were tested. We fabricated BC/S fabrics using circular knitting based on optimal manufacturing parameters. The BC/S complex yarn had an optimum elastic recovery rate of 98.89% when the rotor speed was 10000 r.p.m and the wrap number 4 turns/cm. The optimum tenacity of the yarn containing 44.0 dtex spandex was 4.22 cN/dtex when the rotor speed was 4000 r.p.m. and the wrap number 2 turns/cm. The anion density of the BC/S fabric increased with the wrap number; in particular, the fabric containing 76.9 dtex spandex displayed an optimum anion density of 54 anions/cc.
Badano przędze składające się ze zwęglonych włókien bambusowych oraz wysokoelastycznych włókien typu spandex, których użyto jako włókien rdzeniowych. W pierwszej fazie włókna typu spandex ulegały rozciąganiu, a następnie były owijane włóknami bambusowymi przy wykorzystaniu wirnikowej maszyny skręcającej. Dla określenia właściwości fizycznych wyprodukowanych włókien hybrydowych określono wytrzymałość na zerwanie, wydłużenie i stopień odprężności. Wyprodukowano dzianiny na cylindrycznej maszynie dziewiarskiej przy optymalnych parametrach pracy dla uzyskania określonych właściwości dzianiny. Maksymalna wytrzymałość wyprodukowanych włókien hybrydowych wynosiła około 4 cN/dtex. Gęstość anionowa dzianiny wzrastała ze wzrostem ilości oplotów przędzy.
Źródło:
Fibres & Textiles in Eastern Europe; 2012, 4 (93); 47-50
1230-3666
2300-7354
Pojawia się w:
Fibres & Textiles in Eastern Europe
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Measurement of Surface Profile and Surface Roughness of Fibre-Optic Interconnect by Fast Fourier Transform
Autorzy:
Lin, C. S.
Yang, S. W.
Lin, H. L.
Li, J. W.
Powiązania:
https://bibliotekanauki.pl/articles/221117.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
surface profile
surface roughness
fibre end-face
fast Fourier transform
Opis:
This study proposes a surface profile and roughness measurement system for a fibre-optic interconnect based on optical interferometry. On the principle of Fizeau interferometer, an interference fringe is formed on the fibre end-face of the fibre-optic interconnect, and the fringe pattern is analysed using the Fast Fourier transform method to reconstruct the surface profile. However, as the obtained surface profile contains some amount of tilt, a rule for estimating this tilt value is developed in this paper. The actual fibre end-face surface profile is obtained by subtracting the estimated tilt amount from the surface profile, as calculated by the Fast Fourier transform method, and the corresponding surface roughness can be determined. The proposed system is characterized by non-contact measurement, and the sample is not coated with a reflector during measurement. According to the experimental results, the difference between the roughness measurement result of an Atomic Force Microscope (AFM) and the measurement result of this system is less than 3 nm.
Źródło:
Metrology and Measurement Systems; 2017, 24, 2; 381-390
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mitigation scratch on fused silica optics using CO2 laser
Autorzy:
Liu, C.-M.
Yan, Z.-H.
Yang, L.
Jiang, Y.
Zu, X.-T.
Wang, H.-J.
Liao, W.
Yuan, X.-D.
Zheng, W.-G.
Powiązania:
https://bibliotekanauki.pl/articles/174978.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
mitigation
scratch
fused silica
CO2 laser
Opis:
The scratch on a fused silica surface was treated as a chain of connected damage sites and mitigated one after another using CO2 laser irradiation. The optical microscopy image shows that a scratch with the width of about 30 μm and length of several millimeters can be completely mitigated without the formation of debris and bubbles. The mitigated scratch can survive under raster scan laser irradiation with the fluency increased up to 11.0J/cm2 at 3ns and 351nm. On the contrary, the substrate without CO2 laser mitigation is seriously damaged under this irradiation. The light modulation induced by mitigation is much smaller when the scratch is mitigated before being damaged. The light modulation is about 2 when the distance to the mitigated sample is larger than 20cm. The birefringence induced by residual stress in the mitigated scratch is measured. The retardance of the mitigated scratch before being damaged is not visible. Therefore, residual stress in this mitigated scratch before being damaged should be not a critical potential risk in laser damage.
Źródło:
Optica Applicata; 2016, 46, 3; 387-397
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Existence and asymptotic behavior of solutions for hénon type equations
Autorzy:
Long, W.
Yang, J.
Powiązania:
https://bibliotekanauki.pl/articles/255754.pdf
Data publikacji:
2011
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
Henon equation
cylindrical symmetry
non-cylindrical symmetry
asymptotic behavior
Opis:
This paper is concerned with ground state solutions for the Hénon type equation [formula] in Ω, where Ω = Bk(0, 1) × Bn-k(0, 1) ⊂ Rn and x = (y, z) ∈ Rk × Rn-k. We study the existence of cylindrically symmetric and non-cylindrically symmetric ground state solutions for the problem. We also investigate asymptotic behavior of the ground state solution when p tends to the critical exponent [formula].
Źródło:
Opuscula Mathematica; 2011, 31, 3; 411-424
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Test research on the resistance performance of high-speed trimaran planing hull
Autorzy:
Ma, W.
Sun, H.
Zou, J.
Yang, H.
Powiązania:
https://bibliotekanauki.pl/articles/259708.pdf
Data publikacji:
2013
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
trimaran planing hull
side hulls
high speed
step
resistance
model test
Opis:
In order to identify high-speed navigation ability of trimaran planing hull, as well as investigate the characteristics of its resistance and hull form, ship model tests were conducted to measure resistance, trim and heaving under different displacements and gravity centre locations. The test results were then used to study the influence of spray strips on resistance and sea-keeping qualities. Moreover, different planning surfaces were compared in the model tests which helped to look into influence of steps on hull resistance and its moving position. Also, the resistance features of monohull and trimaran planing hulls, both with and without steps, were compared to each other. From the tests it can be concluded that: the two auxiliary side hulls increase aerodynamic lift at high-speed motion, which improves the hydrodynamic performance; the trimaran planing hull has also excellent longitudinal stability and low wave-making action; when Fr∇> 8, its motion is still stable and two distinct resistance peaks and two changes of sailing state (the second change is smaller) appear; spray strips are favourable for sea-keeping qualities at high speed. The change trends before the second resistance peak as to the resistance and sailing behaviour of trimaran planing hull without steps are the same as for monohull planing hull without steps. but when steps in both hulls exist the change trends are different; more specifically: trimaran planing hull with steps has only one resistance peak and its resistance increases along with its speed increasing, and the resistance is improved at the increasing speed as the number of steps increases.
Źródło:
Polish Maritime Research; 2013, 4; 45-51
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Defect Structure of Nitrogen Doped Czochralski Silicon Annealed under Enhanced Pressure
Autorzy:
Misiuk, A.
Wierzchowski, W.
Wieteska, K.
Londos, C.
Andrianakis, A.
Bak-Misiuk, J.
Yang, D.
Surma, B.
Powiązania:
https://bibliotekanauki.pl/articles/1539028.pdf
Data publikacji:
2010-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.05.cp
61.72.-y
61.72.Ff
61.72.uf
62.50.-p
Opis:
Defect structure of Czochralski grown silicon (Cz-Si) with nitrogen admixture, c_{N} ≤ 5 × $10^{14} cm^{-3}$ (Cz-Si:N), annealed for up to 10 h at 1270-1400 K under hydrostatic Ar pressure ≤ 1.1 GPa, was investigated by synchrotron diffraction topography (HASYLAB, Germany), X-ray reciprocal space mapping, and infrared spectroscopy. Extended defects were not detected in Cz-Si:N processed at up to 1270 K. Such defects were created, however, in Cz-Si:N pre-annealed at 923 K and next processed at 1270 K or in as-grown Cz-Si:N processed at 1400 K. Investigation of temperature-pressure effects in nitrogen-doped silicon contributes to the understanding of defect formation in Cz-Si:N.
Źródło:
Acta Physica Polonica A; 2010, 117, 2; 344-347
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł

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