Дисертації з теми "Power Specturm"
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Borde, Arnaud. "One-Dimensional Power Spectrum and Neutrino Mass in the Spectra of BOSS." Phd thesis, Université Paris Sud - Paris XI, 2014. http://tel.archives-ouvertes.fr/tel-01023004.
Повний текст джерелаStitz, Elizabeth H. "Instantaneous Power Spectrum." Thesis, Monterey, California : Naval Postgraduate School, 1990. http://handle.dtic.mil/100.2/ADA229098.
Повний текст джерелаThesis Advisor(s): Hippenstiel, Ralph D. Second Reader: Cristi, Roberto. "March 1990." Description based on signature page as viewed on August 25, 2009. DTIC Identifier(s): Signal analysis, Time varying spectra, Wigner Ville distribution functions, Rihaczek distribution functions. Author(s) subject terms: Instantaneous Power Spectrum, spectral estimation, nonstationary signal analysis. Includes bibliographical references (p. 108-112). Also available online.
de, Oliveira Paulo M. D. Monica. "Instantaneous Power Spectrum." Thesis, Monterey, California. Naval Postgraduate School, 1989. http://hdl.handle.net/10945/26003.
Повний текст джерелаChiang, Chi-Ting. "Position-dependent power spectrum." Diss., Ludwig-Maximilians-Universität München, 2015. http://nbn-resolving.de/urn:nbn:de:bvb:19-183996.
Повний текст джерелаPerkins, Larry D. "Development and characterization of a low power helium microwave induced plasma for spectrometric determinations of metals and nonmetals." Diss., Virginia Polytechnic Institute and State University, 1989. http://hdl.handle.net/10919/54261.
Повний текст джерелаPh. D.
Hagerman, Karen Allyn. "Instantaneous power spectrum in 1 1 /." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from the National Technical Information Service, 1992. http://edocs.nps.edu/npspubs/scholarly/theses/1992/Jun/92Jun_Hagerman.pdf.
Повний текст джерелаTadros-Attalla, Helen. "Power spectrum analysis of redshift surveys." Thesis, University of Oxford, 1996. https://ora.ox.ac.uk/objects/uuid:5a5786db-748e-4c78-bab8-c89a4eda2f07.
Повний текст джерелаGriffiths, Louise M. "The cosmic microwave background power spectrum." Thesis, University of Oxford, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.249266.
Повний текст джерелаDuniya, Didam Gwazah Adams. "Relativistic corrections to the power spectrum." University of the Western Cape, 2015. http://hdl.handle.net/11394/4787.
Повний текст джерелаThe matter power spectrum is key to understanding the growth of large-scale structure in the Universe. Upcoming surveys of galaxies in the optical and HI will probe increasingly large scales, approaching and even exceeding the Hubble scale at the survey redshifts. On these cosmological scales, surveys can in principle provide the best constraints on dark energy (DE) and modified gravity models and will be able to test general relativity itself. However, in order to realise the potential of these surveys, we need to ensure that we are using a correct analysis, i.e. a general relativistic analysis, on cosmological scales. There are two fundamental issues underlying the general relativistic (GR) analysis. Firstly, we need to correctly identify the galaxy overdensity that is observed on the past light cone. Secondly, we need to account for all the distortions arising from observing on the past light cone, including redshift distortions (with all general relativistic effects included) and volume distortions. These general elativistic effects appear in the angular power spectra of matter in redshift space. We compute these quantities, taking into account all general relativistic large-scale effects, and including the important contributions from redshift space distortions and lensing convergence. This is done for self-consistent models of DE, known as ‘quintessence’, which have only been very recently treated in the GR approach. Particularly, we focus mainly on computing the predictions (i.e. the power spectra) that need to be confronted with future data. Hence we compute the GR angular power spectra, correcting the 3D Newtonian calculation for several quintessence models. We also compute the observed 3D power spectra for interacting DE (which until now have not previously been studied in the GR approach) – in which dark matter and DE exchange energy and momentum. Interaction in the dark sector can lead to large-scale deviations in the power spectrum, similar to GR effects or modified gravity. For the quintessence case, we found that the DE perturbations make only a small contribution on the largest scales, and a negligible contribution on smaller scales. Ironically, the DE perturbations remove the false boost of large-scale power that arises if we impose the (unphysical) assumption that the DE perturbations vanish. However, for the interacting DE (IDE) case, we found that if relativistic effects are ignored, i.e. if they are not subtracted in order to isolate the IDE effects, the imprint of IDE will be incorrectly identified – which could lead to a bias in constraints on IDE, on horizon scales. Moreover, we found that on super-Hubble scales, GR corrections in the observed galaxy power spectrum are able to distinguish a homogeneous DE (being one whose density perturbation in comoving gauge vanishes) from the concordance model (and from a clustering DE) – at low redshifts and for high magnification bias. Whereas the matter power spectrum is incapable of distinguishing a homogeneous DE from the concordance model. We also found that GR effects become enhanced with decreasing magnification bias, and with increasing redshift.
Hoi, Loison. "Cosmological inflation and the primordial power spectrum." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:8881/R/?func=dbin-jump-full&object_id=92301.
Повний текст джерелаHanson, D. "The microwave background beyond the power spectrum." Thesis, University of Cambridge, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.603669.
Повний текст джерелаNicolson, Gavin. "Reconsturcting the modelling the primordial power spectrum." Thesis, Imperial College London, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.508718.
Повний текст джерелаHotchkiss, Shaun. "Inflation beyond the scalar fluctation power spectrum." Thesis, University of Oxford, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.526514.
Повний текст джерелаMohapi, Setumo J. (Setumo James). "Power control for spread spectrum communications systems." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/39756.
Повний текст джерелаMacaulay, Edward Robert Mark. "Cosmology with power spectrum measurements from galaxy surveys." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:bb918260-6747-4133-bdcb-b393d080c6fa.
Повний текст джерелаLoureiro, Arthur Eduardo da Mota. "Galaxy Power Spectrum Analysis: A Monte-Carlo Approach." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-06072015-060434/.
Повний текст джерелаNos próximos anos, diversos levantamentos de galáxias planejam lançar uma quantidade considerável de novos dados, marcando, assim, o início da chamda era da cosmologia de precisão. Cada levantamento possui suas próprias limitações geométricas, que manifestam- se perante os dados na forma de uma função de seleção, ou seja, uma distribuição espacial de cada tipo de galáxia. A partir de um mapa de galáxias (real ou simulado), o principal objetivo desse trabalho foi descobrir como a função de seleção afeta alguns dos parâmetros cosmológicos que podem ser obtidos através de dados futuros de estrutura em larga escala. Portanto, propôs-se um método de Monte-Carlo com cadeias de Markov para estudar os efeitos decorrentes da inclusão dos parâmetros da função de seleção como nuisance parameters. Esse método consiste em combinar simulações de catálogos de galáxias, usando um espectro de potências teórico da matéria junto com um estimador ótimo, a fim de obter ambos espectros (teórico e observacional) e compará-los em uma verossimilhança Gaussiana-multivariada. O método de Monte-Carlo provou-se robusto e capaz de demonstrar os efeitos da função de seleção sobre as estimativas dos parâmetros cosmológicos, comprovando que o simples ato de marginalizar sobre os parâmetros não desejados pode levar a estimativas equivocadas na cosmologia em quesão. Finalmente, esse método foi aplicado nas estimações do parâmetro de Hubble (H0), na densidade de matéria escura (c) e em dois dos parâmetros da equação de estado da energia escura (w0 e wa) com o objetivo de prever tais efeitos para dados futuros do levantamento J-PAS com Galáxias Vermelhas Luminosas.
Lin, Yousi. "Spectrum Management Issues in Centralized and Distributed Dynamic Spectrum Access." Diss., Virginia Tech, 2021. http://hdl.handle.net/10919/104362.
Повний текст джерелаDoctor of Philosophy
Due to the rapid growth in wireless communication demands, the frequency spectrum is becoming increasingly crowded. Traditional spectrum allocation policy gives the unshared access of fixed bands to the licensed users, and there is little unlicensed spectrum left now to allocate to newly emerged communication demands. However, studies on spectrum occupancy show that many licensed users who own the license of certain bands are only active for a small percentage of time, which results in plenty of underutilized spectrum. Hence, a new spectrum sharing paradigm, called dynamic spectrum access (DSA), is proposed to mitigate this problem. DSA enables the spectrum sharing between different classes of users, generally, the unlicensed users in the DSA system can access the licensed spectrum opportunistically without interfering with the licensed users. Based on architecture design, DSA systems can be categorized as centralized and distributed. In centralized systems, a central controller will make decisions on spectrum usage for all unlicensed users. Whereas in distributed systems, unlicensed users can make decisions for themselves independently. To successfully enable DSA, both centralized and distributed DSA systems need to deal with spectrum management issues, such as resource allocation problems and user privacy issues, etc. The resource allocation problems include, for example, the problems to discover and allocate idle bands and the problems to control users' transmit power for successful coexistence. Privacy issues may also arise during the spectrum management process since certain information exchange is inevitable for global decision making. However, due to the Federal Communications Commission's (FCC) regulation, licensed users' privacy such as their location information must be protected in any case. As a result, dynamic and efficient spectrum management techniques are necessary for DSA users. In this dissertation, we investigate the above-mentioned spectrum management issues in both types of DSA systems, specifically, the spectrum sensing challenges with licensed user location privacy issues in centralized DSA, and the spectrum sharing problems in distributed DSA systems. In doing so, we propose novel schemes for solving each related spectrum management problem and demonstrate their efficacy through the results from extensive evaluations and simulations. We believe that this dissertation provides insightful advice for DSA users to solve different spectrum management issues for enabling DSA implementation, and hence helps in a wider adoption of dynamic spectrum sharing.
Law, Eugene. "How to Estimate the Unmodulated Carrier Power Level of a Modulated Telemetry Signal." International Foundation for Telemetering, 2006. http://hdl.handle.net/10150/604416.
Повний текст джерелаThis paper will present methods to both measure the unmodulated carrier power of a modulated signal and to estimate the unmodulated carrier power level from the measured power spectrum. The unmodulated carrier power level is needed to convert measured spectra into units of dBc.
Vázquez, Oliver Miguel Ángel. "Beamforming design and power control for spectrum sharing systems." Doctoral thesis, Universitat Politècnica de Catalunya, 2014. http://hdl.handle.net/10803/144654.
Повний текст джерелаLast, Michael. "Finding abrupt changes in the time-varying power spectrum /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2005. http://uclibs.org/PID/11984.
Повний текст джерелаMulye, Apoorva. "Power Spectrum Density Estimation Methods for Michelson Interferometer Wavemeters." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/35500.
Повний текст джерелаChen, Jia Yuan. "Spectrum and power optimisation in wireless multiple access networks." Thesis, University College London (University of London), 2008. http://discovery.ucl.ac.uk/1445389/.
Повний текст джерелаMaciel, de Paiva Junior Nilson. "Low-power and radiation resilient approaches for spectrum sensing." Electronic Thesis or Diss., Institut polytechnique de Paris, 2020. http://www.theses.fr/2020IPPAT040.
Повний текст джерелаThe advancement of technology has enabled a great increase in the number of users and the amount of information to be transmitted. In recent years, the demand for high download rates, massive connection, low latencies, and energy efficiency has increased, mainly due the popularization of IoT devices and the introduction of industry 4.0. This has led to a significant increase in demand for the frequency spectrum to accommodate new services or to improve existing ones. One of the alternatives to deal with this problem is the use of cognitive radios (CRs). They are able to sense the spectrum and see which bands are not currently being used. Among the various challenges related to CR, spectrum sensing is one of the most important and one of the primary functions of these radios. Wideband spectrum sensing presents several challenges, including antennas and processing a lot of data. However, in several moments the spectrum can be considered sparse allowing the use of compressive sensing (CS) in order to reduce the amount of samples required and thereby reducing processing resources. In terms of hardware, the use of CS can be translated in analog-to-information converters (AICs) instead of implementing analog-to-digital converters (ADCs) with high sampling rates. Furthermore, it is interesting to implement low-power devices. Downscaling transistors to nanometers helps to reduce consumption and area. However, other alternatives have been studied to decrease the leakage power. Among these alternatives, Magnetic Tunnel Junction (MTJ) has been very promising. In addition, the downscaling transistors makes circuits more sensitive to Single Event Transient (SET), and although MTJ is more robust than transistors to radiation, it is necessary to study how this impact is and how to reduce it. In this context, this thesis focuses on the SET effects analysis and MTJ applications which can be used in an AIC to perform the wideband spectrum sensing. The main contributions of this thesis are the analysis of SET effects in a comparator which is one of the main components of an ADC, analysis of SET effects in MTJ structures, and the proposition of an MTJ-based ADC which can be used in an AIC to perform the wideband spectrum sensing
Ma, Zheng. "Impeller Power Draw Across the Full Reynolds Number Spectrum." University of Dayton / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1406766474.
Повний текст джерелаPearce, David Andrew James. "Improving spectrum efficiency in fixed cellular communication systems." Thesis, University of York, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341520.
Повний текст джерелаTaruya, Atsushi, Kazuya Koyama, and Takahiko Matsubara. "Signature of primordial non-Gaussianity on the matter power spectrum." American Physical Society, 2008. http://hdl.handle.net/2237/11326.
Повний текст джерелаLazanu, Andrei. "The power spectrum and bispectrum of inflation and cosmic defects." Thesis, University of Cambridge, 2016. https://www.repository.cam.ac.uk/handle/1810/256999.
Повний текст джерелаQu, Qi. "Power and spectrum efficient communications in wireless ad hoc networks." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2008. http://wwwlib.umi.com/cr/ucsd/fullcit?p3304197.
Повний текст джерелаTitle from first page of PDF file (viewed June 16, 2008). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 105-114).
Schlaich, Andreas [Verfasser]. "Time-dependent spectrum analysis of high power gyrotrons / Andreas Schlaich." Karlsruhe : KIT Scientific Publishing, 2015. http://www.ksp.kit.edu.
Повний текст джерелаBrannon, Raymond James. "The radio spectrum requirements of broadband power line telecommunications systems." Thesis, Open University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.430560.
Повний текст джерелаMirtavoosi, Mahyari Mohammad. "Power and rate optimization in shared-spectrum wireless communication networks." Thesis, King's College London (University of London), 2013. https://kclpure.kcl.ac.uk/portal/en/theses/power-and-rate-optimization-in-sharedspectrum-wireless-communication-networks(6945f10d-6434-4577-b557-4e3593a32b53).html.
Повний текст джерелаYang, Xianzhen. "Power Spectrum Prediction of Amplified Dual-Band LTE-Advanced Signals." PDXScholar, 2018. https://pdxscholar.library.pdx.edu/open_access_etds/4351.
Повний текст джерелаNayfeh, Mahir Ali. "Nonlinear dynamics in power systems." Thesis, Virginia Tech, 1990. http://hdl.handle.net/10919/41582.
Повний текст джерелаMaster of Science
Comley, Vivian Edward. "Aspects of synchronization in direct sequence spread spectrum systems." Thesis, University of Bath, 1985. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355305.
Повний текст джерелаDITOLLA, ROBERT JOHN. "RANDOM VIBRATION ANALYSIS BY THE POWER SPECTRUM AND RESPONSE SPECTRUM METHODS (WHITE NOISE, FINITE-ELEMENT, VANMARCKE, DENSITY, NASTRAN)." Diss., The University of Arizona, 1986. http://hdl.handle.net/10150/183836.
Повний текст джерелаChakraborty, Joyraj, and Venkata Krishna chaithanya varma Jampana. "ANFIS BASED OPPURTUNISTIC POWER CONTROL FOR COGNITIVE RADIO IN SPECTRUM SHARING." Thesis, Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-5042.
Повний текст джерелаJayalath, A. D. S. (Angiyaddage Dhammika Srilal) 1967. "OFDM for wireless broadband communications (peak power reduction, spectrum and coding)." Monash University, School of Computer Science and Software Engineering, 2002. http://arrow.monash.edu.au/hdl/1959.1/7995.
Повний текст джерелаJayalath, A. D. S(Angiyaddage Dhammika Srilal) 1967. "OFDM for wireless broadband communications(peak power reduction, spectrum and coding) /." Monash University, School of Computer Science and Software Engineering, 2002. http://arrow.monash.edu.au/hdl/1959.1/7995.
Повний текст джерелаJahren, Ole Henrik. "Emergent Behaviour in the Frequency-Power Spectrum of Discrete Dynamic Networks." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for datateknikk og informasjonsvitenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-23038.
Повний текст джерелаEfroimsky, Michael. "Temperature power-spectrum of the primordial gravity-waves in inflationary cosmology." Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239355.
Повний текст джерелаTang, Wing-shun, and 鄧榮信. "Study of power spectrum fluctuation in accretion disc by cellular automaton." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B31221695.
Повний текст джерелаUchaipichat, Nopadol. "The prediction of defibrillation outcome using time-frequency power spectrum methods." Thesis, Edinburgh Napier University, 2005. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.418238.
Повний текст джерелаPaykari, Paniez. "Binning of the primordial power spectrum and optimal galaxy survey design." Thesis, Imperial College London, 2009. http://hdl.handle.net/10044/1/5547.
Повний текст джерелаCresswell, Bevan. "Inflationary cosmology, phase transitions and primordial power spectra." Thesis, University of Canterbury. Physics and Astronomy, 2004. http://hdl.handle.net/10092/5578.
Повний текст джерелаYoo, Byungseok. "Practical Aspects of Assessing Nonlinear Ultrasonic Response of Cyclically Load 7075-T6 Aluminum." Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/36335.
Повний текст джерелаMaster of Science
Osborne, William P., Don Whiteman, and Sharmin Ara. "ON THE PERFORMANCE OF PCM/FM+ FM/FM SYSTEMS." International Foundation for Telemetering, 1993. http://hdl.handle.net/10150/608872.
Повний текст джерелаMuch modem telemetry is transmitted in a digital format and to be compatible with existing range equipment the digital data is impressed on the carrier using FM modulation. The receiving system in common use employs an FM limiter/discriminator as a detector followed by an integrate and dump matched filter for bit detection. This system has been studied by previous authors [1] and it is well known that in the absence of frequency uncertainty the optimum transmission parameters consist of a modulation index of .7 (peak-to-peak deviation divided by the bit rate) and an IF filter bandwidth equal to the bit rate followed by a limiter discriminator. In many cases, there is a need for some small amount of analog telemetry transmission in addition to the digital data discussed above. In these cases it is common practice to include analog subcarriers on the main carrier with the digital data modulating the carrier at baseband, the resulting system is called PCM/FM + FM/FM. These hybrid analog/digital systems are the subject of this paper. In particular this paper addresses the performance of these systems through simulation using the Block Oriented System Simulator (BOSS) from Comdisco and with analytical techniques to obtain the BER versus SNR curves for these systems. The simulation is used over a wide range of parameters to find the optimum values of modulation index and IF bandwidth for these systems.
Moura, Tiago Sousa. "High efficiency energy harvesting system from D-TV spectrum." Master's thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/18868.
Повний текст джерелаA recolha de energia do meio ambiente para alimentar dispositivos como forma de os tornar auto-sustentáveis tem vindo cada vez mais a suscitar interesse. Por outro lado, o crescimento contínuo do espectro resultante das telecomunicações constitui uma grande oportunidade para a colheita de energia. Assim sendo, neste trabalho e proposto um sistema altamente e ciente de recolha de energia de rádio-frequência que utiliza o sinal da televisão digital (D-TV) portuguesa e que converte-o em tenso que poder a ser reaproveitada. De forma a ser vantajoso, o sistema e otimizado para operar a baixos níveis de potência. Assim, o presente trabalho pretende também fornecer orientações para o correto desenvolvimento do sistema de colheita de energia para baixa potência de entrada, contribuindo para o desenvolvimento de projetos futuros. O sistema e dividido numa antena recetora e num retificador. Para o retificador são propostas três soluções distintas: um díodo série, um díodo paralelo e um duplicador de tensão. A eficiência obtida e semelhante para as três configurações - cerca de 54% para um sinal de entrada sinusoidal com um nível de potência de -10.5 dBm. Medições com o multiplicador de tensão e o sinal real da D-TV como entrada mostraram uma eficiência de 63% para o mesmo nível de potência. Relativamente à antena, e proposta uma patch com slots e com um elemento parasita que utiliza como substrato dielétrico FR-4. Esta configuração resulta da necessidade de melhorar a largura de banda da microstrip simples. Medições mostraram um aumento da largura de banda em cerca de 4 vezes quando em comparação com uma patch simples.
Collect energy from the surroundings is being biased to power-up devices in order to turn them self-sustainable. On the other hand, the spectrum resultant from the telecommunications tends to progressively increase and becomes wide-reaching, constituting an enormous opportunity to energy harvesting. Thus, in this work a high e ciency radio-frequency energy harvesting system is proposed that takes uses of the Portuguese Digital Television (D-TV) signal to obtain Direct Current (DC) power. To be useful, the system is optimized to operate at low power conditions. So, this work also aims to provide reliable guidelines in the design of energy harvesting systems with low-input power. The system is divided into an antenna and a recti er. For the recti er, three di erent solutions are presented: a single-series diode, a singleshunt diode and a voltage doubler con guration. The e ciency is similar for the three recti ers { around 54% with a sine-wave excitation and -10.5 dBm input power. Field measurements with the voltage doubler has proven 63% e ciency for the same input power. As receiver antenna is proposed a slotted patch with a stacked parasitic based on FR-4 substrate. This con guration results from the need to improve the bandwidth of the basic microstrip patch. Measurements have proven and enhancement around 4 times in comparison with a basic patch.
Josan, Amandeep Singh. "Constraints on the power spectrum of primordial perturbations from small-scale structure." Thesis, University of Nottingham, 2011. http://eprints.nottingham.ac.uk/11713/.
Повний текст джерелаSalton, Grant. "The power spectrum of cosmic microwave background polarization from cosmic string wakes." Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=121559.
Повний текст джерелаNous calculons la contribution intégrée au spectre de puissance de la polarisation du fond diffus cosmique (CMB) grâce aux sillages des cordes cosmiques. Une introduction aux défauts topologique, cordes cosmiques, de polarisation du CMB, et aux champs spin–s est donnée. Nous utilisons ensuite ces outils pour calculer le spectre de puissance angulaire de la polarisation des modes E et B grâce aux des sillages des cordes cosmiques, dans la limite du ciel plat. Nous trouvons que les termes de corrélation croisée (EB, ET, BT) sont zero, tandis que les spectres de puissance pour EE et BB ont la même forme et grandeur. Ce résultat contraste le polarisation du mode B causée par les fluctuations Gaussiennes, qui disparaîssent. Cependant, nous trouvons que la forme du spectre de puissance causée par les sillages de cordes cosmiques est très similaire au spectre en mode B prédite par lentille gravitationnelle, mais avec une amplitude globale trés faible. Donc, le signal du sillage de corde cosmique est trop faible pour être measuré au-dessus l'indicatif du lentille. Aussi, les méthodes de soustraction du fond serait très difficile. Nous trouvons que l'amplitude maximum dans le spectre de puissance sqrt(l(l+1)C_l/2pi) est d'environ 10^(-4) pour l~400.Nous étudions brièvement le forme asymptotique du spectre de puissance, et nous trouvons que Cl est quasi–constant en l jusqu'à un tournant correspondant à la taille angulaire du sillage le plus important. Nous déterminons alors quel sillage donne la contribution dominante au spectre de puissance complet. Nous trouvons que les sillages dominants sont ceux qui ont été formés à l'epoque de l'égalité de matière et de rayonnement, et qui croisent notre cône de lumière passé à l'époque de recombinaison. Nous concluons que l'indicatif dans l'espace Fourier est trop faible pour être détecté. Donc, les recherches futures devraient se concentrer sur les caractéristiques l'espace spatial.
Parker, Michael Julian Reid. "Studies on power spectrum analysis of the fetal heart rate during labour." Thesis, Queen's University Belfast, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356874.
Повний текст джерела