Temat: analytical approach

Skocz do pozycji: 1.

Tytuł:: Reliability assessment of an exemplary system operating at variable conditions
Autorzy:: Kołowrocki, K.
Kuligowska, E.
Soszyńska-Budny, J.
Tematy:: system reliability
system operation process
analytical approach; Pokaż więcej
Wydawca:: Uniwersytet Morski w Gdyni. Polskie Towarzystwo Bezpieczeństwa i Niezawodności
Powiązania:: https://bibliotekanauki.pl/articles/2069201.pdf Link otwiera się w nowym oknie
Opis:: The reliability analysis of a multistate complex system subjected to varying in time its operation process is performed. A semi-Markov process is applied to construct the multistate model of the system operation process and its main characteristics are determined. Analytical linking of the system operation process model with the system multistate reliability model is proposed to get a general reliability model of the complex system operating at varying in time operation conditions and to find its reliability characteristics. The constructed integrated general model of a complex multistate system reliability, linking its reliability model and its operation process model and considering variable at different operation states its reliability structure and its components reliability parameters is applied to the reliability evaluation of an exemplary system.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 2.

Tytuł:: Flow modeling in a jet engine
Autorzy:: Hlavńa, V.
Rajčan, P.
Tematy:: jet engine
flow
experimental approach
numerical approach
analytical approach; Pokaż więcej
Wydawca:: Instytut Techniczny Wojsk Lotniczych
Powiązania:: https://bibliotekanauki.pl/articles/247566.pdf Link otwiera się w nowym oknie
Opis:: It is possible to monitor effects related to flow in a jet aircraft engine by the three basic approaches - analytical, numerical and experimental Each approach has undergone changes and has been developed to the stage of its effective use. To efficiently manage the scientific and research work it is appropriate to use effective links among all three basic approaches. An experimental approach requires a test stand on which the characteristics of a usually geometrically reduced object or the actual object itself are verified. The principles of geometric and hydrodynamic similarities are applied. This approach is time and economically demanding and not all aerodynamic processes can be reliably simulated. Other disaavantages can be the occurrence of measurement errors, errors due to changes in the scale, influences of chemical reactions and influence of Reynolds number. Due to a very fast onset, development and challenges of IT, the numerical approach has become mostly used. It can provide sufficient information on an examined phenomenon in a particular object. It does not need any substantial simpliflcations, it is less financially demanding than the experimental approach, but it needs efficient processors with a huge memory capacity. Its disadvantage is a relatively large dependence of achieved results accuracy on the perfection of numerical models and models of turbulence in the areas with prevailing influence ofviscosity. The usage ofanalytical relations from mathematical andphysical analysis of the flow fleld is the fundamental of the analytical approach of observing the laws related to flowing. The paper deals with possibilities, procedures, advantages, and disadvantages of the mentioned approaches together with a presentation of some results from research and development activities carried out by the authors.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 3.

Tytuł:: Heave analysis of shallow foundations founded in swelling clayey soil at N’Gaous city in Algeria
Autorzy:: Khennouf, Abdelaziz
Baheddi, Mohamed
Tematy:: clayey soil
swelling
analytical approach
foundation heave
numerical modelling; Pokaż więcej
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Powiązania:: https://bibliotekanauki.pl/articles/1845129.pdf Link otwiera się w nowym oknie
Opis:: The design of shallow foundations on swelling soils needs a thorough study to evaluate the effect of swelling potential soil on the final foundation heave. For this reason, a simple analytical approach based on the soil stress state under the foundation can be used to calculate the foundation heave. This paper reports a set of analytical and numerical analysis using the finite-difference code (FLAC 3D), performed on an isolated shallow foundation founded on a swelling soil mass at N’Gaous city in Batna Province, Algeria, subjected to distributed vertical loads. Further, the influence of some parameters on total heave was analyzed, such as the embedded foundation and soil stiffness. The analysis results from the proposed 3D modelling was compared and discussed with analytical results. The numerical results obtained show a good agreement with the analytical solutions based on oedometer tests proposed in the literature, and deliver a satisfactory prediction of the heave of the shallow foundations.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 4.

Tytuł:: A model for changing the technological process for the growth of epitaxial layers by means of the heating of the growth zone
Autorzy:: Pankratov, Evgeny L.
Tematy:: epitaxy
gas phase
improvement of properties
film
analytical approach
modeling; Pokaż więcej
Wydawca:: Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Powiązania:: https://bibliotekanauki.pl/articles/29520098.pdf Link otwiera się w nowym oknie
Opis:: The nonstationary transfer of heat during epitaxial layer growth in gas phase epitaxy reactors is analyzed within the work. Based on this analysis, several recommendations on the organization of the heating of the growth zone to increase the homogeneity of the epitaxial layers were formulated. An approach to analyze the transfer of heat during epitaxial layer growth from the gas phase is also introduced. The approach leads to the possibility of simultaneously accounting for heat transfer nonlinearity and changes of parameters of heat transfer in both space and time.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 5.

Tytuł:: Analysis of system operation process influence on its reliability
Autorzy:: Kuligowska, E.
Tematy:: system reliability
system operation process
analytical approach
Monte Carlo simulation; Pokaż więcej
Wydawca:: Uniwersytet Morski w Gdyni. Polskie Towarzystwo Bezpieczeństwa i Niezawodności
Powiązania:: https://bibliotekanauki.pl/articles/2069392.pdf Link otwiera się w nowym oknie
Opis:: The paper presents analytical and Monte Carlo simulation methods applied to the reliability evaluation of a system operating in two different operation states. A semi-Markov process is applied to construct the system operation model and its main characteristics are determined. Analytical linking of this operation model with the system reliability model is proposed to get a general reliability model of the system operating at two varying in time operation conditions and to find its reliability characteristics. The application of Monte Carlo simulation based on this general model to the reliability evaluation of this system is proposed as well. The exemplary results obtained from those two considered methods are illustrated.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 6.

Tytuł:: Thermoelastic stresses in functionally graded rotating annular disks with variable thickness
Autorzy:: Allam, M. N. M.
Tantawy, R.
Zenkour, A. M.
Tematy:: functionally graded
variable thickness
semi-analytical approach
rotating
thermal effect; Pokaż więcej
Wydawca:: Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Powiązania:: https://bibliotekanauki.pl/articles/949321.pdf Link otwiera się w nowym oknie
Opis:: This article presents semi-analytical solutions for stress distributions in exponentially and functionally graded rotating annular disks with arbitrary thickness variations. The disk is under pressure on its boundary surfaces and exposed to temperature distribution varying linearly across thickness. Material properties are supposed to be graded in the radial direction of the disk and obeying to two different forms of distribution of volume fraction of constituents. Different conditions at boundaries for stresses and displacement are discussed. Accurate and efficient solutions for displacement and stresses in rotating annular disks are determined using infinitesimal theory. Numerical results are carried out and discussed for different cases. It can be deduced that the gradient of material properties and thickness variation as well as the change of temperature sources have a specific effect in modern applications.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 7.

Tytuł:: On changing the properties of a multilayer structure by preliminary processing of a substrate
Autorzy:: Pankratov, Evgeny L.
Tematy:: gas phase epitaxy
improvement of properties of films
analytical approach for modeling; Pokaż więcej
Wydawca:: Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Powiązania:: https://bibliotekanauki.pl/articles/29520076.pdf Link otwiera się w nowym oknie
Opis:: In this paper, the effect of the preliminary processing of a substrate on the properties of a grown heterostructure is investigated. It is shown that the growth of an epitaxial layer on a buffer layer after preliminary annealing (before the growth) makes it possible to decrease the value of mismatch-induced stress. An analytical approach has been introduced for the analysis of mass and heat transfer in a multilayer structure accounting for mismatch-induced stress.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 8.

Tytuł:: Designing of Steel CHS Columns Showing Maximum Compression Resistance
Autorzy:: Marcinowski, Jakub
Sadowski, Mirosław
Tematy:: compressed bar
CHS section
shape optimization
buckling criterion
analytical approach
pręt
przekrój CHS
optymalizacja
wyboczenie; Pokaż więcej
Wydawca:: Uniwersytet Zielonogórski. Oficyna Wydawnicza
Powiązania:: https://bibliotekanauki.pl/articles/1838080.pdf Link otwiera się w nowym oknie
Opis:: The paper deals with a shape optimisation procedure of steel, compressed bars. Circular hollow sections (CHS) of variable cross sections and variable wall thickness are taken into account. The proposed procedure for designing of steel rods exhibiting maximum compression resistance is effective and possible to use in engineering practice. The advantage of the proposed shape of the bar is that it allows to increase the value of its load carrying capacity, i.e. it ensures the transfer of a higher value of compressive force than similar, solid struts of the same mass and length. The extent of the increase in the load capacity relative to the load capacity of the reference solid, cylindrical bar depends on the slenderness of the reference bar and ranges from 60% to 170%. Due to this very beneficial fact, it can be used wherever it is required to maintain a certain stiffness and an increased value of compressive force is desired, as well as in constructions where it is necessary to reduce weight while maintaining the adopted mechanical parameters, e.g. values of load bearing capacity. Final results achieved in the research were presented in the form of the flow chart allowing to design the compressed columns of optimum shape.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 9.

Tytuł:: Experimental and analytical approaches on air spring absorbers made of ldpe polymer
Autorzy:: Obst, Maciej
Kurpisz, Dariusz
Jakubowski, Michał
Tematy:: LDPE absorbers
reaction on impact
analytical approach
mechanical parameters
impact test
LDPE bellows impact
protective; Pokaż więcej
Wydawca:: Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
Powiązania:: https://bibliotekanauki.pl/articles/58907255.pdf Link otwiera się w nowym oknie
Opis:: Damping and energy-consuming elements can be found in many technical applications. This means these component types can prevent fractures or injuries in the case of products or people, respectively. In the last time, many modern applications and inventions associated with the reduction of the effects of an impact are observed especially in the mode of transportation safety area. The significant development of the automotive industry, increasing popularity of motorbikes, electric bikes and scooters, sports field, etc., require new solutions for personal safety protection. Human head and neck protection, and other body parts protection are typical groups of solutions from biomechanics and mechanical engineering. Authors have investigated LDPE-made pneumatic absorbers under axial impact force. Based on the experimental approach and analytical model, mechanical characteristics are presented. Impact force value, deceleration and damping for different loading conditions are shown. Because safety systems’ impact protective features can be matched to impact conditions, results indicated that absorber damping could possibly be a good solution for them, shaping the impact characteristics according to safety requirements.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 10.

Tytuł:: On the prognosis of the growth of a heterostructure from a gas phase to analyze the possibility of decreasing mismatch-induced stresses
Autorzy:: Pankratov, Evgeny L.
Tematy:: growth
gas phase
decreasing
mismatch-induced stresses
radiation processing
analytical approach
analyzing of mass
heat transfer; Pokaż więcej
Wydawca:: Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Powiązania:: https://bibliotekanauki.pl/articles/29520105.pdf Link otwiera się w nowym oknie
Opis:: An approach to decreasing mismatch-induced stress in a heterostructure by radiation processing during growth from the gas phase is introduced in this paper. Within the framework of the approach with decreasing mismatch-induced stresses, one can find the acceleration of the recombination and diffusion of radiation defects generated during radiation processing. An analytical approach for analyzing mass and heat transfer is also introduced. The approach provides the opportunity to simultaneously take into account spatial and temporal variations of mass transfer parameters. At the same time, the approach allows the nonlinearity of the considered processes to be taken into account.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Informacja

Wyszukujesz frazę "analytical approach" wg kryterium: Temat