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1732. Analitical simulation of application of FFT based spectral method of fatigue cycle counting for multiaxial stress on example of pulse excited beam
- Creator:
- Kozien, Marek Stanisław and Smolarski, Dariusz
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- fatigue, FFT analysis, vibration, and cycle counting
- Language:
- English
- Description:
- Vibration of engineering structures results in time variable displacements functions. For realistic structures modes of vibration are determined by exciting frequency and the natural frequencies of the structure. Hence, the components of stress tensor are time function too. In the presented paper the general idea of method of cycle-counting based on the FFT analysis for engineering structures is discussed and analytically verified for the case vibrating beam excited by series pulse-type force with no damping. and V názvu článku je jazyková chyba/překlep - analitical - správně = analytical
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1733. Analogické kvantové pohybové rovnice elektronových a fotonových vln v izotropních prostředích
- Creator:
- Pospíšil, Jaroslav and Pluháček, František
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- quantum physics, applied mathematics, kvantová fyzika, and aplikovaná matematika
- Language:
- Czech
- Description:
- The formulations and interpretations of some formally analogous expressions of the single-particle scalar quantum wave equations of electrons and photons, propagated in adequate isotropic static media under weak signals and interaction phenomena, are presented in this article. and V prezentovaném článku jsou obsaženy formulace a interpretace některých formálně analogických tvarů jednočásticových skalárních kvantových vlnových rovnic šířících se elektronů a fotonů v přiměřených izotropních statických prostředích při slabých signálech a interakčních jevech.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1734. Analogový elektro-optický přenosový systém pro účely měření
- Creator:
- Švarný, Jiří
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- analog systems, analog signal processing, measurement, analogové systémy, analogové zpracování signálů, měření, elektro-optický převodník, širokopásmový přenos, přenosový systém, externí modulace, LiNbO3 Mach-Zehnderův modulátor, and intenzitní modulace
- Language:
- Czech
- Description:
- The work deals with design and implementation of an analogue electro-optic transmission system convenient to solve some specialized tasks in the field of diagnostics and measurements. The proposed system is designed to solve several requirements that are beyond the limits of conventional metallic transmission medium. Especially it is the case of broadband transmission, extreme length of the transmission medium and high galvanic barrier between input and output that have to be achieved simultaneously. and Práce popisuje vývoj a realizaci analogového elektro-optického přenosového systému použitelného v některých speciálních případech diagnostiky a měření. Navržený přenosový systém řeší několik vzájemně se limitujících požadavků, které není možné standardním metalickým propojením splnit. Jde zejména o současné dosažení velké šířky frekvenčního pásma, délky přenosového média a dostatečné galvanické bariéry mezi vstupem a výstupem.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1735. Analyse and verification of in-pipe bristled minimachine prototype
- Creator:
- Dovica, Miroslav, Gorzás, Michal, Kaťuch, Peter, and Kováč, Jozef
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- thin pipe, minimachine, smart bristle, and difference friction
- Language:
- English
- Description:
- This paper describes experimental work done on a prototype of in-pipe bristled minimachine, which locomotes in pipe with inner diameter under 40 mm. The principle of minimachine locomotion is based on difference friction force between bristle tip and pipe wall. The new bristle design and its mathematical and graphical model will be presented. and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1736. Analysis of a TV polemical discourse
- Creator:
- Čmejrková, Světla
- Format:
- Type:
- model:internalpart and TEXT
- Language:
- English and Czech
- Description:
- Mediální dialog ztrácí některé rysy přirozeného dialogu tváří v tvář, který leží v jeho půdorysu, a získává rysy další, neboť komunikace tu přestupuje přes hranice primární řečové situace. Televizní dialog je dialog veřejný, který se vede před diváckým publikem a pro toto publikum. Divák je nejen svědkem, ale pravým cílem, k němuž je dialog směrován. Stať analyzuje komunikační situaci, při níž jsou ve studiu přítomni redaktor a dva hosté, představitelé různých profesí a názorových proudů (ekonom a ekoložka) i různých stanovisek к určité otázce (globalizace). Redaktor se obrací s otázkami střídavě к oběma. aby je vzájemně konfrontoval a spor vyhrotil. Dotazovaní hosté se snaží nejen odpovídat na otázky redaktora (to je jejich základní role v interview), ale i zpochybňovat či přímo vyvracet odpovědi druhého z hostí (role často neméně důležitá). Hosté komunikují nejen s redaktorem, ale komunikují i mezi sebou navzájem, ať už skrytě, či zjevně, s cílem získat diváka na svou stranu. Stať analyzuje toto interview v souvislosti s otázkou typologie debat a debat založených na konfliktu zájmů a konfliktu hodnot.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1737. Analysis of chlorophyll fluorescence decays of isolated thylakoids in various stages of greening
- Creator:
- Kowalczyk, A., Waloszek, A., and Frąckowiak, D.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- chloroplast, Cucumis sativus, 3-(3,4-dichlorophenyl)-1,1-dimethyl urea, etiochloroplast, fractal model, and photooxidation
- Language:
- Multiple languages
- Description:
- The decay of chlorophyll (Chl) fluorescence of etiochloroplasts isolated in various stage of greening of cucumber cotyledons was analysed in order to get structural information on a photosynthetic apparatus. Two model decays, multiexponential and stretched exponential, were applied in the analysis. The quality of fit in these two models was different in various stages of chloroplast greening. The two-exponent model did not provide a good fit at early greening stages. To improve the fit it was necessary to introduce an additional third component which became very low at later stages. However, chloroplasts in the early stage of greening could also be described by a stretched exponential with parameters indicating rather planar (two-dimensional) arrangement of donor and acceptor molecules. The chloroplasts treated by DCMU and/or photooxidized by strong irradiance exhibit a similar character of fractal decay as untreated samples but in the multiexponential model the exact values of lifetimes and amplitudes of components vary. This suggests that the structure of investigated system does not dramatically change as a result of these two types of treatment. and A. Kowalczyk, A. Waloszek, D. Frąckowiak.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1738. Analysis of D1 protein turnover in photoautotrophic suspension cultured cells of Chenopodium rubrum. 1. Effects of actual irradiance and growth irradiance
- Creator:
- Schmid, V. and Schäfer, C.
- Format:
- Type:
- model:internalpart and TEXT
- Language:
- Multiple languages
- Description:
- Turnover of Dl protein as influenced by actual irradiance and growth irradiance was analyzed in the photoautotrophic suspension cultured cells of Chenopodium rubrum. Proteins were labelled by adding 35S-methionine to the ceU suspension. Following electrophoresis the labelled proteins were detected by autoradiography. Relative label incorporation into the Dl protein containing band was calculated from scans of the autoradiographs and ušed as an estimate of Dl protein synthesis (pulse experiments) and Dl protein degradation (chase experiments). Total label incorporation was not affected by the irradiance during labelling but Dl protein synthesis and degradation were boťh increased at 900 pmol m-2 s*i as compared to 120 pmol m'2 s*^ The effect of growth irradiance was analysed by comparing cells which had been pre-cultured at 120 pmol m'2 s"^ (HL cells) and 900 pmol s‘i (PIL cells) for at least 6 d. The inhibition of chloroplastic protein synthesis by cUoramphenicol exacerbated the effect of photoinhibitory irradiance on the chlorophyll fluorescence parameters in these cells. The inhibitor effect was more pronoímced in PIL cells than in HL ones. This points to a higher chloroplastic protein synthesis capacity of the former cell type. Due to a considerable difference in total label incorporation pulse experiments could not be ušed to check this hypothesis. The chase experiments indicated that the Dl-protein degradation rate was higher in PIL cells tiian in HL cells. Probably a generál increase in the Dl protein tumover occiu^ if the cells are exposed to photoinhibitory irradiances for a prolonged period.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1739. Analysis of diaphragm movement, during tidal breathing and during its activation while breath holding, using MRI synchronized with spirometry
- Creator:
- Kolář, P., Jiří Neuwirth, Jan Šanda, Vojtěch Suchánek, Zuzana Svatá, J. Volejník, and Martin Pivec
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, držení těla, physiology, posture, diaphragm fiction, magnetic resonance Paging, thorax, 14, and 612
- Language:
- English
- Description:
- a1_Using magnetic resonance imaging (MRI) in conjunction with synchronized spirometry we an alyzed and compared diaphragm movement during tidal breathing and voluntary movement of the diaphragm while breath holding. Breathing cycles of 16 healthy subjects were examined using a dynamic sequence (77 slices in sagittal plane during 20 s, 1NSA, 240x256, TR4.48, TE2.24, FA90, TSE1, FOV 328). The amplitude of movement of the apex and dorsal costophren ic angle of the diaphragm were measured for two test conditions: tidal breathing and voluntary breath holding. The maximal inferior and superior positions of the diaphragm were subtracted from the corresponding positions during voluntary movements while breath holding. The average amplitude of inferio-superior mo vement of the diaphragm apex during tidal breathing was 27.3±10.2 mm (mean ± SD), and during voluntary movement while breath holding was 32.5±16.2 mm. Movement of the costophrenic angle was 39±17.6 mm during tidal breathing and 45.5±21.2 mm during voluntary movement while breath holding. The inferior position of the diaphragm was lower in 11 of 16 subjects (68.75 %) and identical in 2 of 16 (12.5 %) subj ects during voluntary movement compared to the breath holding. Pearson’s correlation coefficient was used to demonstrate that movement of the costophrenic angle and apex of the diaphragm ha d a linear relationship in both examined situations (r=0.876). A correlation was found between the amplitude of diaphragm movement during tidal breathing and lung volume (r=0.876). The amplitude of movement of the diaphragm with or without breathing showed no correlation to each other (r=0.074). The moveme nt during tidal breathing shows a correlation with the changes in lung volumes. Dynamic MRI demonstrated that individuals are capable of moving their diaphragm voluntarily, but the amplitude of movement differs from person to person., a2_In this study, the movements of the diaphragm apex and the costophr enic angle were synchronous during voluntary movement of the diaphragm while breath holding. Although the sample is small, this study confirms that the function of the diaphragm is not only respiratory but also postural and can be voluntarily controlled., P. Kolář, J. Neuwirth, J. Šanda, V. Suchánek, Z. Svatá, J. Volejník, M. Pivec., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1740. Analysis of dominant factors influencing moisture change of broad-ovate leaves of Populus euphratica Oliv. in extremely arid region
- Creator:
- Fu, A. H., Li, W. H., Chen, Y. N., Zhu, C. G., and Ma, J. X.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- botanika, botany, environmental factors, extreme arid environment, gas exchange, Populus euphratica Oliv., and water potential
- Language:
- Multiple languages
- Description:
- We studied the dominant environmental factors that affect the gas-exchange characteristics and water potential (ψ) of broad-ovate leaves of Populus euphratica Oliv. in extreme arid area of Tarim River, China, and their correlation to water status of P. euphratica by analyzing on-field monitored meteorological data, soil moisture and salinity, P. euphratica leaf gas exchange and ψ, and revealed the indicative threshold of environmental factors for P. euphratica leaf water changes and growth. The results indicated that meteorological factors such as air relative humidity (RH), air temperature (T air), etc. are the dominant factors. The threshold value of RH is (48.19 ± 1.06)% for P. euphratica growth, i.e. RH from 10.69% to 48.19% is suitable for P. euphratica growth in extremely arid region of Tarim River. This study provides a theoretical basis for reducing drought damage to P. euphratica and maintaining normal growth of P. euphratica by in-time watering. and A. H. Fu ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public