Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "Wang, K.-K." wg kryterium: Autor

  Lista filtrów
Wyrównaj
Wyświetlanie 1-25 z 76
Tytuł:
Thermal Decomposition Kinetics of Hexanitrohexaazaisowurtzitane/Ammonium Perchlorate
Autorzy:
Zhu, Y.-L.
Wang, K.-K.
Shan, M.-X.
Zheng, X.-D.
Jiao, Q.-J.
Wang, J.-S.
Powiązania:
https://bibliotekanauki.pl/articles/358067.pdf
Data publikacji:
2016
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
hexanitrohexaazaisowurtzitane
ammonium perchlorate
thermal analysis
thermal decomposition kinetics
Opis:
The thermal decomposition kinetics of hexanitrohexaazaisowurtzitane/ ammonium perchlorate (HNIW/AP) have been investigated by thermogravimetrydifferential scanning calorimetry-mass spectrometry (TG-DSC-MS) simultaneous analysis. TG showed that there were three weight loss processes for the thermal decomposition of the HNIW/AP mixture. The first was ascribed mainly to the thermal decomposition of HNIW, while the second and third were assigned to that of AP. The presence of AP has little effect on the thermal decomposition process of the HNIW component. The apparent activation energy of the thermal decomposition of the HNIW component, calculated by the Kissinger method, was little changed compared to that of neat HNIW. The addition of HNIW to AP caused the onset and end temperatures of the thermal decomposition to be decreased and the decomposition process to be shortened. The high-temperature and lowtemperature decomposition processes of AP became blurred in the presence of HNIW, and this was supported by the MS results.
Źródło:
Central European Journal of Energetic Materials; 2016, 13, 1; 149-159
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical analysis of the tip vortex in an air-conditioners propeller fan
Autorzy:
Wang, J.
Wu, K.
Powiązania:
https://bibliotekanauki.pl/articles/1955218.pdf
Data publikacji:
2006
Wydawca:
Politechnika Gdańska
Tematy:
tip vortex
internal flow field
propeller fan
numerical simulation
Opis:
A steady, incompressible, turbulent flow field inside a propeller fan used in an air conditioner has been analyzed numerically using the single-equation Spalart-Allmaras turbulence model. It has been found that the formation of tip vortex starts from the blade tip's suction side at about one third of the axial chord's length aft of the rotor's leading edge. It is due to the rolling-up of the intense shear layer flow between the main axial flow and the suck-in inward flow caused by the large pressure difference between the pressure and the suction sides. The tip vortex passes through the blade passage in a curve reversed towards the direction of the blade's rotation. Its trace is partial to the tangential direction as it goes into the aft part of the blade passage covered by the shroud and, simultaneously, its trace in the radial direction is turned from the outward direction to the inward direction. The operating flow rates have an important effect on the axial position of the tip vor-tex's trace, while its effect on the radial position is negligible. At law flow rates, the vortex disappears at a location closer to the leading edge. The effect of the shroud's width on the tip vortex's trajectory is notable. For a fan with a wide shroud, the trace of the tip vortex moves upstream with a smaller radial influence region than that of a fan with a narrower shroud.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2006, 10, 2; 101-112
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study of the characteristics about insulation damage based on the accelerated life tests
Badanie charakterystyk uszkodzeń izolacji w oparciu o testy przyspieszonego starzenia
Autorzy:
Yang, Y. H.
Wang, K.-S.
Powiązania:
https://bibliotekanauki.pl/articles/300857.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
accelerated life testing
competing failure mode
insulation degradation
Gompertz-type relation shape parameter
Opis:
In this study the Maximum Likelihood Estimator is taken to identify the characteristics of insulation failure about the class-H motors by considering the accelerated life testing data under censored situation from Nelson. Based on the Weibull survival modeling the failure is expressed as the series connection of three modes, namely the turn, phase, and ground, respectively, the so-called competing failure. The main concern in present investigation is about the variation of shape parameters, β with the temperature. The Gompertz-type relation of βi(T) is suggested with the reference temperature, Tri for the i-th failure mode. It is found that the Tri ’s not only distinguish the characteristics of cumulative damage process about the insulation, but also involve the estimation of mean-time-to-failure (MTTF). Physically Tri denotes the turning point of varied βi as the i-th failure mode becomes moderate in a sense of less capability about the accumulation of insulation damage at higher temperature where corresponds the thermal degradation process. The numerical results indicate that the insulation technique used is acceptable as the operation temperature kept in the use condition 363K. According to the predicted lifetime as the temperature rises up to 440K, which still within the allowed range in application, the turn structure needs to be rearranged primarily, then the phase next. The ground mode has only influence on the failure at much higher temperature.
Źródło:
Eksploatacja i Niezawodność; 2013, 15, 4; 325-331
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Residual life prediction for highly reliable products with prior accelerated degradation data
Prognozowanie trwałości resztkowej wysoce niezawodnych produktów na podstawie danych historycznych z przyspieszonych badań degradacji
Autorzy:
Wang, H.-W.
Teng, K.-N.
Powiązania:
https://bibliotekanauki.pl/articles/301443.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
residual life
Bayesian inference
random parameters
Wiener process
acceleration factor
trwałość resztkowa
wnioskowanie bayesowskie
parametry losowe
proces Wienera
współczynnik przyspieszenia
Opis:
To precisely predict the residual life for functioning products is a key of carrying out condition based maintenance. For highly reliable products, it is difficult to obtain abundant degradation data to precisely predict the residual life under normal stress levels. Thus, how to make use of historical degradation data to improve the accuracy of the residual life prediction is an interesting issue. Accelerated degradation testing, which has been widely used to evaluate the reliability of highly reliable products, can provide abundant accelerated degradation data. In this paper, a residual life prediction method based on Bayesian inference that takes accelerated degradation data as prior information was studied. A Wiener process with a time function was used to model degradation data. In order to apply the random effects of all the parameters of a Wiener process, the non-conjugate prior distributions were considered. Acceleration factors were introduced to convert the parameter estimates from accelerated stress levels to normal stress levels, so that the proper prior distribution types of the random parameters can be selected by the Anderson-Darling statistic. A Markov Chain Monte Carlo method with Gibbs sampling was used to evaluate the posterior means of the random parameters. An illustrative example of self-regulating heating cable was utilized to validate the proposed method.
Precyzyjne przewidywanie trwałości resztkowej użytkowanego produktu stanowi klucz do prawidłowego utrzymania ruchu w oparciu o bieżący stan techniczny (condition-based maintenance).W przypadku produktów o wysokiej niezawodności, trudno jest uzyskać ilość danych degradacyjnych, która umożliwiałaby precyzyjne prognozowanie trwałości resztkowej przy normalnym poziomie obciążeń. Dlatego też bardzo ważnym zagadnieniem jest wykorzystanie historycznych danych degradacyjnych umożliwiających zwiększenie trafności prognozowania trwałości resztkowej. Przyspieszone badania degradacyjne, które powszechnie wykorzystuje się do oceny niezawodności wysoce niezawodnych produktów, mogą dostarczać bogatych danych o przyspieszonej degradacji. W przedstawionej pracy badano metodę prognozowania trwałości resztkowej opartą na wnioskowaniu bayesowskim, w którym jako uprzednie informacje wykorzystano dane z przyspieszonych badań degradacji. Dane degradacyjne modelowano za pomocą procesu Wienera z funkcją czasu. Aby móc zastosować efekty losowe wszystkich parametrów procesu Wienera, rozważano niesprzężone rozkłady a priori. Wprowadzono współczynniki przyspieszenia , które pozwoliły na przekształcenie szacowanych wartości parametrów z poziomu obciążeństosowanych w próbie przyspieszonej do poziomu obciążeń normalnych, co umożliwiło wybór odpowiednich typów parametrów losowych rozkładu a priori zwykorzystaniem statystyki testowej Andersona-Darlinga. Metodę Monte Carlo opartą na łańcuchach Markowa z próbnikiem Gibbsa wykorzystano do oceny średnich a posteriori parametrów losowych. Proponowaną metodę zweryfikowano na postawie przykładu samoregulującego przewodu grzejnego.
Źródło:
Eksploatacja i Niezawodność; 2016, 18, 3; 379-389
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical analysis of controlling separation in axial cascades by excitation of periodical incoming wake
Autorzy:
Liu, F.
Wang, J.
Wu, K.
Powiązania:
https://bibliotekanauki.pl/articles/1933188.pdf
Data publikacji:
2008
Wydawca:
Politechnika Gdańska
Tematy:
unsteady excitation
compressor cascade
separation control
incoming wake
vortex shedding
Opis:
Numerical analysis has been performed of time-space structures in a large turning angle axial cascade subject to unsteady incoming wake excitation. The results have shown that intentional unsteady excitation could increase the cascade's time-averaged performance. As a result, the vortex structures corresponding to the external exciting frequency are strengthened and other disordered vortices are involved, so that the separation structures of the suction surface are translated from disorder to order. Two interaction regimes between incoming periodic wakes and separation structures are analyzed, indicating that turbulent kinetic energy can enhance momentum interchange and that wave-vortex resonance can promote rolled-up and plus-minus pairing of vortices. Based .on these, responses of separation structures from two periodic incoming wake regimes are compared. The feasibility of far-field noise reduction in ducting fans by using periodic incoming wake is considered.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2008, 12, 1-2; 21-34
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical analysis of internal flow phenomena in a multi-blade centrifugal fan
Autorzy:
Wang, J.
Ou, Y.
Wu, K.
Powiązania:
https://bibliotekanauki.pl/articles/1964163.pdf
Data publikacji:
2005
Wydawca:
Politechnika Gdańska
Tematy:
multi-blade centrifugal fan
internal flow field
CFD
Opis:
A three-dimensional, steady, incompressible, turbulent flow field inside a multi-blade centrifugal fan used in an air-conditioner has been analyzed numerically. Reynolds-averaged Navier-Stokes equations with the standard k-epsilon turbulence model have been discretized by the finite volume method. The calculation results have shown complex three-dimensional characteristics of the flow, especially in the blade passages near the shroud side. The results have revealed a boundary layer separating the flow from the leading edge on the blade suction surface, the flow's reversal from the high pressure region inside the volute to the low pressure region near the impeller inlet, the flow's recirculation near the shroud side, a jet-wake pattern at the rotor exit, pressure fluctuation on the blade surface, etc. Some of the numerical results agree well with previous experiment.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2005, 9, 2; 245-256
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparative Theoretical Investigation on Energetic Substituted Furazanyl Ethers
Autorzy:
Liu, N.
Wang, K.
Shu, Y.
Zeman, S.
Wang, B.
Wang, W.
Powiązania:
https://bibliotekanauki.pl/articles/358622.pdf
Data publikacji:
2018
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
furazanyl ethers
heats of formation
bond dissociation energy
detonation performance
melting point
Opis:
Furazanyl ether has great potential to be an important candidate as a casting explosive and energetic plasticizer. The density functional theory (DFT) method was used to investigate the heats of formation (HOFs), molecular stability, detonation performance and melting point of a series of substituted furazanyl ethers at B3LYP/6-311G(d,p) level. The results show that the introduction of –N3 or –N(O)=N– groups significantly improves the HOFs values of the derivatives. The bond dissociation energies (BDEs) were analyzed, showing that the N–O bond in the furazan ring is the weakest for most compounds and the ring is vulnerable to cleavage in thermal decomposition. The calculation of density, detonation velocities and detonation pressures suggests that the substitution of –NF2, –CF(NO2)2, furoxan or –N(O)=N– group is an effective method for enhancing their detonation performance. The melting points were determined according to the variation of specific heat capacity, and good estimates were obtained in comparison with the available experimental data. Taking into account the detonation performance and melting point, four compounds are favoured for application in melt cast explosive or energetic plasticizers.
Źródło:
Central European Journal of Energetic Materials; 2018, 15, 1; 47-71
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dual reference beam digital off-axis holography for exact suppression of zero-order term and twin image without spectrum loss
Autorzy:
Wang, M.
Wang, K.
Zheng, M.
Li, F.
Wu, J.
Powiązania:
https://bibliotekanauki.pl/articles/174894.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
noise suppression
pixel-by-pixel multiplication
digital off-axis holography
Opis:
In this paper, we describe an effective approach to suppressing zero-order term and twin image by using pixel-by-pixel multiplication of double holograms in digital off-axis holography. This method records two holograms, respectively, by using the reference waves in different directions. It shows not only a simpler algorithm and easier implementation in experiment, but also exact and complete suppression of the zero-order term and twin image without any spectrum loss of the object in the image reconstruction, particularly when the image and the zero-order term are fairly close to each other. The experimental result approves of the theoretical prediction very well. This approach provides an effective solution to suppressing undesired noises in the digital off-axis holography.
Źródło:
Optica Applicata; 2017, 47, 3; 435-443
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Piecewise reliability-dependent hazard rate for composites under fatigue loading adjustment
Konstrukcja funkcji ryzyka uszkodzeń kawałkami zależnej od niezawodności dla kompozytów poddanych różnym scenariuszom obciążenia zmęczeniowego
Autorzy:
Chen, C.-L.
Wang, K.-S.
Powiązania:
https://bibliotekanauki.pl/articles/281955.pdf
Data publikacji:
2012
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
fatigue loading adjustment
hazard rate function
dynamical reliability
Monte Carlo simulation
linear damage sum
Opis:
Based on the derived transition period and reliability drop, this paper proposes a method of piecewise combination of the reliability-dependent hazard rate function named (eocp) model to describe the dynamical reliability in a two-stage fatigue loading process. First, the parameters eo, c, p are fitted through simulated failure data under various constant- amplitude cyclic stresses. The reliability of the high-low loading process is described piecewise with the corresponding values of (eo, c, p) for each respective stress level, and maintains Ra in the transition period while Ra denotes the reliability at which the stress level changes. The reliability of the low-high process is determined by subtracting the portion of reliability drop at Ra from the piecewise fitted curves. The proposed reliability behavior is verified successfully. The linear damage sum is found to be larger than unity for the high-low loading, and on the contrary for the low-high cases. A larger difference between the stress level changed results in larger deviation of damage sum from unity, especially when Ra near 0.9.
W oparciu o wyznaczony okres przejściowy i spadek niezawodności, artykuł prezentuje metodę określania funkcji ryzyka uszkodzenia kawałkami zależnej od poziomu niezawodności, zwanej (eocp) i służącej do modelowania dynamicznej niezawodności dla dwustanowych procesów obciążania zmęczeniowego. Na poczatku, parametry eo, c, i p dopasowano do danych otrzymanych w drodze symulacji uszkodzeń pod wpływem działania cyklicznych naprężeń o kilku stałych amplitudach. Niezawodność dla obciążeń przechodzących od dużej amplitudy do małej opisano kawałkami zależnymi od poziomu przykładanych naprężeń i odpowiadającymi im wartościami eo, c, i p. Wynosi ona Ra w okresie przejściowym, gdzie Ra jest niezawodnością, przy której poziom naprężeń jest zmieniany. Niezawodność przy obciążeniu rosnącym wyznaczono, odejmując część jej spadku przy Ra od kawałkami dopasowanych krzywych. Zaproponowany sposób opisu niezawodności sukcesywnie weryfikowano. Zaobserwowano, że liniowa suma uszkodzeń przekracza jedność dla scenariusza obciążeń stopniowo malejących i nie osiąga tej wartości w przypadku przeciwnym. Większe różnice w poziomach obciążeń skutkowały w większych odstępstwach liniowej sumy uszkodzeń od jedności. Szczególnie duże zauważono dla Ra = 0.9.
Źródło:
Journal of Theoretical and Applied Mechanics; 2012, 50, 1; 231-250
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
High-speed catamaran’s longitudinal motion attenuation with active hydrofoils
Autorzy:
Hu, K.
Ding, Y.
Wang, H.
Powiązania:
https://bibliotekanauki.pl/articles/259910.pdf
Data publikacji:
2018
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
High-speed catamaran
longitudinal motion attenuation
2.5D theory
hydrofoil
Opis:
This paper mainly studies the longitudinal motion prediction method and control technology of high-speed catamaran using the active hydrofoils. To establish the longitudinal motion equations of the ship basing on the 2.5D theory. Using the CFD software to obtain the hydrodynamic data of the hydrofoil. Bring the hydrodynamic expression of hydrofoils into the longitudinal motion equations of the ship. Predicting the longitudinal motion of High-speed catamaran before and after added the hydrofoils. A specific catamaran has been predicted with this approach, the result indicates this approach is workable and this prediction approach provides the theoretical basis for assessing the stabilization ability of appendages and possess the engineering practical value.
Źródło:
Polish Maritime Research; 2018, S 2; 56-61
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mechanical analysis and research of the conveyor belt of plane turning belt conveyor based on discrete element method
Autorzy:
Li, D. Y.
Wang, S.
Hu, K.
Powiązania:
https://bibliotekanauki.pl/articles/224069.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
przenośnik taśmowy
siła taśmy przenośnikowej
metoda elementów dyskretnych
optymalizacja
belt conveyor
conveyor belt force
Discrete Element Method
optimization design
Opis:
In view of the size and the change of the load force of the conveyor belt at the turning point of the plane turning belt conveyor, the influencing factors of the stress of the conveyor belt at the turning point of the plane turning belt conveyor under full load condition are analyzed. A three dimensional model of the turning point of the plane turning belt conveyor is established. Combined with previous research experience, the formula for calculating the load is put forward. Based on discrete element method, multiple sets of internal curve elevation angle and the belt speed are used for dynamic simulation analysis. The results showed that the middle of conveyor belt is the most stressed, the lateral force second, the force of the inner conveyor belt is the least. Outside force increases with the increase of speed; there is no change in the middle band; the inner band force decreases with the increase of the velocity. Outside force decreases with the decrease of the inclination angle. With the change of the inclination angle, the force is basically unchanged. With the decreasing of the inclination angle, the force increases gradually. By optimizing the design parameters of the plane turning belt conveyor, the force of belt is reduced, and the service life of belt is improved.
Źródło:
Archives of Transport; 2017, 41, 1; 55-62
0866-9546
2300-8830
Pojawia się w:
Archives of Transport
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Phytoremediation of phenol using Polygonum orientale and its antioxidative response
Autorzy:
Wang, K.
Cai, J.
Xie, S.
Feng, J.
Wang, T.
Powiązania:
https://bibliotekanauki.pl/articles/205372.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Polygonum orientale
phenol
phytoremediation
antioxidant enzyme
osmotic regulator
Opis:
Polygonum orientale with beautiful red flowers can be found as one dominant species in the vicinity of most water bodies and wetlands in China. However, its phytoremediation potential has not been sufficiently explored because little is known about its resistance to inorganic or organic pollutants. We investigated P. orientale response to low and moderate levels of phenol stress (≤ 80 mg L-1). Endpoints included phenol tolerance of P. orientale and the removal of the pollutant, antioxidant enzyme activities, damage to the cell membrane, osmotic regulators and photosynthetic pigments. In plant leaves, phenol stress significantly increased the activities of peroxidase (POD) and catalase (CAT), as well as the contents of proline, soluble sugars and carotenoids, whereas superoxide dismutase (SOD), H2O2 and electrolyte leakage (EL) levels remained unaltered. On the other hand, there were significant decreases of soluble protein and chlorophyll contents. We demonstrated that, in combination with phenol tolerance and its removal, P. orientale has efficient protection mechanisms against phenol-induced oxidative damage (≤ 80 mg L-1). We propose that P. orientale could be used as an alternative and interesting material in the phytoremediation of phenol.
Źródło:
Archives of Environmental Protection; 2015, 41, 3; 39-46
2083-4772
2083-4810
Pojawia się w:
Archives of Environmental Protection
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study of flotation behavior and mechanism of cervantite activation by copper ions
Autorzy:
Wang, J.
Wang, Y.
Fu, K.
Xu, L.
Wang, Z.
Sun, H.
Xiao, J.
Powiązania:
https://bibliotekanauki.pl/articles/110228.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
flotation
cervantite
copper ions
activation mechanism
Opis:
Copper-ion activation plays a highly important role in cervantite (Sb2O4) flotation. Without metal-ion activation, cervantite cannot be floated by sodium oleate. In this study, flotation tests were conducted to study the effect of Cu2+ on the flotation behaviours of cervantite and quartz (SiO2) as the main gangue mineral. Metal-ion adsorption capacities, zeta potentials, solution chemistry and X-ray photoelectron spectra were analyzed to study the adsorption behavior and mechanism of copper ions and sodium oleate interaction with the minerals surfaces. The results demonstrate that under weakly acidic conditions, cervantite can be flotated and separated from quartz by the addition of copper ions. The reason is that copper ions can be selectively adsorbed on the cervantite surface under weakly acidic conditions, thereby promoting the adsorption of sodium oleate onto the cervantite surface by chemical adsorption. Conversely, copper ions are weakly adsorbed on quartz surfaces below pH 6.1, and sodium oleate cannot be adsorbed on quartz surfaces by chemical adsorption. The hydroxy copper species are integral to the selective activation of cervantite over quartz.
Źródło:
Physicochemical Problems of Mineral Processing; 2018, 54, 3; 814-825
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new approach for simultaneous shape and topology optimization based on dynamic implicit surface function
Autorzy:
Guo, H.
Zhao, K.
Wang, M. Y.
Powiązania:
https://bibliotekanauki.pl/articles/970141.pdf
Data publikacji:
2005
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
optymalizacja topologiczna
pochodna topologiczna
topology optimization
implicit
surface function
topological derivative
level set
Opis:
In the present paper, a new approach for structural topology optimization based on dynamic implicit surface function (DISF) is proposed. DISF is used to describe the shape/topology of a structure, which is approximated in terms of the nodal values. Then, a relationship is established between the element stiffness and the values of the implicit surface function on its four nodes. In this way and with some non-local treatments of the design sensitivities, not only the shape derivative but also the topological derivative of the optimal design can be incorporated in the numerical algorithm in a unified way. Numerical experiments demonstrate that by employing this approach, the computational efforts associated with DISF (and level set) based algorithms can be diminished. Clear optimal topologies and smooth structural boundaries free from any sign of numerical instability can be obtained simultaneously and efficiently.
Źródło:
Control and Cybernetics; 2005, 34, 1; 255-282
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Derivation of Closed-Form Design Equations for Idealized Operation of Inverse Class-E Power Amplifiers at Any Duty Ratio
Autorzy:
Wang, Y.
Foo, S. K.
He, Q.
Powiązania:
https://bibliotekanauki.pl/articles/226130.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Class E
power amplifier
numerical simulation
Opis:
Complementary to the conventional class-E topology, inverse class-E operation has several advantages over the class-E counterpart, such as lower peak switch voltage and smaller circuit inductance, which are attractive to high power RF design and MMIC implementation. This paper derives the closed-form design equations that can be used to synthesize the idealized operation of inverse class-E power amplifiers at any switch duty ratio. Calculation of the key design parameters, such as the maximum switch voltage and circuit components values, is elaborated and compared with the case of conventional class-E operation. Further, the theoretical analysis is confirmed and verified by numerical simulations performed on a 500mW, 2.4 GHz idealized inverse class-E power amplifier.
Źródło:
International Journal of Electronics and Telecommunications; 2015, 61, 3; 281-287
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Positive solutions of arbitrary order nonlinear fractional differential equations with advanced arguments
Autorzy:
Ntouyas, S. K
Wang, G.
Zhang, L.
Powiązania:
https://bibliotekanauki.pl/articles/256029.pdf
Data publikacji:
2011
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
positive solution
advanced arguments
fractional differential equations
superlinear (sublinear) condition
uniqueness
Opis:
In this paper, we investigate the existence and uniqueness of positive solutions to arbitrary order nonlinear fractional differential equations with advanced arguments. By applying some known fixed point theorems, sufficient conditions for the existence and uniqueness of positive solutions are established.
Źródło:
Opuscula Mathematica; 2011, 31, 3; 433-442
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Effectiveness of Master Plans: Case Studies of Biologically Active Areas in Suburban Zones
Autorzy:
Błasik, Magdalena
Wang, Tong
Kazak, Jan K.
Powiązania:
https://bibliotekanauki.pl/articles/2105520.pdf
Data publikacji:
2022
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
master plan
spatial planning
effectiveness
suburban zone
Opis:
Sustainable development on a local scale requires well-functioning instruments in the spatial planning system. Any weakness in the planning system may result in forms of spatial development that are socially, environmentally or economically disadvantageous. Therefore, the aim of this study was to examine whether master plans and land development monitoring in the Polish system are effective instruments in shaping sustainable spatial development. The factor analyzed was the share of a biologically active area and four villages located near a regional city were analyzed. Data from master plans, cadaster and orthophoto maps were used in this study. Verification of land use made it possible to evaluate whether the properties meet the provisions of spatial planning documents. In each of the analyzed villages, properties that do not meet the provisions of master plans were identified. In one of the villages, more than half of the properties had a smaller share of biologically active areas than permitted by the local law. The research also analyzed alternative scenarios of the potential impact of the application of permanent vegetation on sealed surfaces. These results showed that using green roofs, for example, can significantly reduce the problem of local laws being broken. The results quantitatively confirm that the provision of master plans in the Polish system are not effective tools in regulating land development.
Źródło:
Geomatics and Environmental Engineering; 2022, 16, 3; 27--40
1898-1135
Pojawia się w:
Geomatics and Environmental Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
PIV measurement of tube-side in a shell and tube heat exchanger
Autorzy:
Wang, K.
Zhang, Z.
Liu, Q.
Tu, X.
Hyoung-Bum, K.
Powiązania:
https://bibliotekanauki.pl/articles/778192.pdf
Data publikacji:
2018
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
shell and tube heat exchanger
tube-side
PIV
unsteady flow
Opis:
In order to improve the performance of the shell and tube heat exchanger, a porous baffle and a splitter bar are employed in this research. Through the arrangement of the porous baffle in the tube-side inlet and the splitter bar in the tube, the flow distribution of liquid in the heat exchanger is improved. PIV technology is used to investigate the unsteady flow in the tube-side inlet and the outlet of different models. The porous baffle significantly improves the flow of fluid in the shell and tube heat exchanger, especially by eliminating/minimizing the maldistribution of fluid flow in the tube-side inlet. The performance of the arc baffle is better than that of the straight baffle. The splitter bar has a minimal effect on the flow field of the tube-side inlet, but it effectively improves the flow in the tube bundle and restrains the vortex generation in the tube-side outlet.
Źródło:
Polish Journal of Chemical Technology; 2018, 20, 1; 60-66
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application study on cooperative drainage technology for mining-affected pressure relief gas in overlaying adjacent seams
Badanie zastosowania połączonej technologii odprowadzania gazu dla gazu rozprężonego w przyległych pokładach złożowych
Autorzy:
Wang, K.
Zang, J.
Zhou, A.
Gao, H.
Powiązania:
https://bibliotekanauki.pl/articles/348651.pdf
Data publikacji:
2012
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
przyległe pokłady węgla
odmetanowanie
wzbogacenie strefy
technologia łączonego odprowadzania gazu
overlaying adjacent seams
mining-affected pressure relief gas
zoning enrichment
cooperative drainage technology
Opis:
During the mining process of 12# coal seam in Yangquan mine area, gas quantity emitting from overlaying adjacent seams was high and gas concentration in upper corners and return airways of mining faces often exceeded limitation. To solve these problems, through the combination of theoretical study, numerical simulation and on-site observation, the high-low zoning enrichment law of the mining-affected pressure relief gas in overlaying adjacent seams of 12# coal seam was formulated. According to this law, the cooperative drainage technology was proposed, namely arranging the high-located and low-located boreholes to drain the gas respective in high and low enrichment zones. By applying the cooperative drainage technology, the safety production status of mining faces of 12# coal seam in Nanzhuang mine has been significantly ameliorated, advance efficiency, drainage rate and drainage quantity have been improved greatly, carbon emission has been reduced and the environment has been protected, resource utilization has been improved, the service life of the mine will be extended. In a word, good economic, social and environmental benefits have been achieved, meanwhile, a safe, efficient, and sustainable exploitation of the mine has been realized.
Podczas eksploatacji ściany nr 12 w Yangquan zanotowano dużą ilość gazu wydobywającego się z przyległych pokładów węgla. Koncentracja metanu w chodniku nadścianowym bardzo często przekraczała wartości dopuszczalne. Aby rozwiązać te problemy, sformułowano zasadę wysokiego/niskiego odmetanowania dla dekompresji metanu w przyległych do ściany nr 12 pokładach węgla na podstawie symulacji numerycznych oraz obserwacji. W odniesieniu do tej zasady zaproponowano technologię łączonego odprowadzania gazu poprzez otwory wiertnicze zlokalizowane odpowiednio na niższym i wyższym poziomie odpowiednich stref metanowości. Zastosowanie technologii odprowadzania łączonego przyczyniło się do znacznej poprawy bezpieczeństwa produkcji na przodku nr 12 kopalni Nanzhuang, zwiększenia wydajności, prędkości odprowadzania i ilości odprowadzanego gazu, obniżenia emisji dwutlenku węgla oraz lepszej ochrony środowiska, a także lepszego wykorzystania zasobów i wydłużenia okresu eksploatacji kopalni. Krótko mówiąc, uzyskano znaczne korzyści ekonomiczne, społeczne i środowiskowe, przy jednoczesnym zapewnieniu bezpiecznej, wydajnej i zrównoważonej eksploatacji kopalni.
Źródło:
AGH Journal of Mining and Geoengineering; 2012, 36, 3; 385-393
1732-6702
Pojawia się w:
AGH Journal of Mining and Geoengineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Design and test of a new high-current electronic current transformer with a Rogowski coil
Autorzy:
Zhang, M.
Li, K.
He, S.
Wang, J.
Powiązania:
https://bibliotekanauki.pl/articles/221051.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Rogowski coil
high-current
electronic current transformers
electrical measurements
Opis:
This paper describes the design and test of a new high-current electronic current transformer based on a Rogowski coil. For better performances, electronic current transformers are used to replace conventional electro-magnetic inductive current transformers based on ferromagnetic cores and windings to measure high-current on the high voltage distribution grids. The design of a new high-current electronic current transformer is described in this paper. The principal schemes of the prototype and partial evaluation results are presented. Through relative tests it is known that the prototype has a wide dynamic range and frequency band, and it can allow high accuracy measurements.
Źródło:
Metrology and Measurement Systems; 2014, 21, 1; 121-132
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Improved dynamic control method for energy storage units in PV dominated microgrids
Autorzy:
Wang, Q.
Liu, Y.
Song, W.
Xuan, K.
Powiązania:
https://bibliotekanauki.pl/articles/141382.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
current correction coefficient
load distribution
PV DC microgrid
secondary control
weighted calculation
Opis:
In a PV-dominant DC microgrid, the traditional energy distribution method based on the droop control method has problems such as output voltage drop, insufficient power distribution accuracy, etc. Meanwhile, different battery energy storage units usually have different parameters when the system is running. Therefore, this paper proposes an improved control method that introduces a reference current correction factor, and a weighted calculation method for load power distribution based on the parameters of battery energy storage units is proposed to achieve weighted allocation of load power. In addition, considering the variation of bus voltage at the time of load mutation, voltage secondary control is added to realize dynamic adjustment of DC bus voltage fluctuation. The proposed method can achieve balance and stable operation of energy storage units. The simulation results verified the effectiveness and stability of the proposed control strategy.
Źródło:
Archives of Electrical Engineering; 2018, 67, 4; 885-898
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Focusing properties of partially coherent dark hollow Gaussian beams through a thin lens system
Autorzy:
Dong, Y
Zhao, C
Wang, K
Cai, Y
Powiązania:
https://bibliotekanauki.pl/articles/175075.pdf
Data publikacji:
2015
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
focusing properties
partially coherent
dark hollow beam
focal shift
Opis:
This paper investigated the focal shift of partially coherent dark hollow Gaussian beams through a thin lens system. An analytic expression of the irradiance distribution of the focusing partially coherent dark hollow Gaussian beams in the back focal plane has been given by using the Collins formula. The focus shift of focused partially coherent dark hollow Gaussian beams in different parameters is studied in detail by numerical calculations. It is found that the absolute value of the focal shift of partially coherent dark hollow Gaussian beams decreases as the transverse coherence width or the order of the dark hollow Gaussian beams or a parameter of the dark hollow Gaussian beams increases.
Źródło:
Optica Applicata; 2015, 45, 2; 151-161
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Association between apparent temperature and hypertension hospital admissions: a case study in rural areas in western China
Autorzy:
Zhai, G.
Wang, Y.
Zhang, K.
Tian, Y.
Powiązania:
https://bibliotekanauki.pl/articles/28763043.pdf
Data publikacji:
2023
Wydawca:
Instytut Medycyny Wsi
Źródło:
Annals of Agricultural and Environmental Medicine; 2023, 30, 3; 490-497
1232-1966
Pojawia się w:
Annals of Agricultural and Environmental Medicine
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dynamic electric vehicles charging load allocation strategy for residential area
Autorzy:
Wang, Y.
Ma, X.
Wang, F.
Hou, X.
Sun, H.
Zheng, K.
Powiązania:
https://bibliotekanauki.pl/articles/140939.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
electric vehicles
charging power management
allocation strategy
priority assessment
Opis:
A large amount of electric vehicles (EVs) charging load will bring significant impact to the power system. An appropriate resource allocation strategy is required for securing the power system safety and satisfying EVs charging demand. This paper proposed a power coordination allocation strategy of EVs’ in distribution systems. The strategy divides the allocation into two stages. The first stage is based on scores assigned to EVs through an entropy method, whereas the second stage allocates energy according to EV’s state of charge. The charging power is delivered in order to maximize EV users’ satisfaction and fairness without violation of grid constraints. Simulation on a typical power-limited residential distribution network proves the effectiveness of the strategy. The analysis results indicate that compared with traditional methods, EVs, which have higher charging requirement and shorter available time will get more energy delivered than others. The root-mean-square-error (RMSE) and standard-deviation (SD) results prove the effectiveness of the methodology for improving the balance of power delivery.
Źródło:
Archives of Electrical Engineering; 2018, 67, 3; 641--654
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Review of Technology of Personal Heating Garments
Autorzy:
Wang, F.
Gao, C.
Kuklane, K.
Holmer, I.
Powiązania:
https://bibliotekanauki.pl/articles/89962.pdf
Data publikacji:
2010
Wydawca:
Centralny Instytut Ochrony Pracy
Tematy:
energy save
cold protection
personal heating garment (PHG)
human comfort
Opis:
Modern technology makes garments smart, which can help a wearer to manage in specific situations by improving the functionality of the garments. The personal heating garment (PHG) widens the operating temperature range of the garment and improves its protection against the cold. This paper describes several kinds of PHGs worldwide; their advantages and disadvantages are also addressed. Some challenges and suggestions are finally addressed with regard to the development of PHGs.
Źródło:
International Journal of Occupational Safety and Ergonomics; 2010, 16, 3; 387-404
1080-3548
Pojawia się w:
International Journal of Occupational Safety and Ergonomics
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-25 z 76

Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies