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Academic literature on the topic 'SPECTRUM APPLICATIONS'

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Published: 11 September 2023

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Journal articles on the topic "SPECTRUM APPLICATIONS"

1

Long, Junbo, Haibin Wang, and Peng Li. "Applications of Fractional Lower Order Frequency Spectrum Technologies to Bearing Fault Analysis." Mathematical Problems in Engineering 2019 (August 27, 2019): 1–24. http://dx.doi.org/10.1155/2019/7641383.

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The traditional spectral analysis method is used to study the characteristics of bearing fault signals in frequency domain, which is reasonable and effective in general cases. However, it is proved that the fault signals have heavy tails in this paper, which are α stable distribution, and 1<α<2, and even the noises belong to α stable distribution. Then the conventional spectral analysis methods degenerate and even fail under α stable distribution environment. Several improved frequency spectral analysis methods are proposed employing fractional lower order covariation or fractional lower order covariance in this paper, including fractional lower order Blackman-Tukey covariation spectrum (FLOBTCS), fractional lower order periodogram covariation spectrum (FLOPCS), and fractional lower order welch covariation spectrum (FLOWCS). In order to suppress side lobe and improve resolution, we present novel fractional lower order autoregression (FLO-AR) and fractional lower order autoregressive moving average (FLO-ARMA) parameter model frequency spectrum methods, and the calculation steps are summarized. The proposed spectrum methods are compared with the existing methods based on second-order statistics under Gaussian and SαS distribution environments, and the results show that the new algorithms have better performance than the traditional methods. Finally, the improved methods are applied to estimate frequency spectrums of the normal and outer race fault signals, and it is demonstrated that they are effective for fault diagnosis.

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Корсунская, Юлия, and Yulia Korsunskaja. "Heuristic model of solar X-ray spectrum according to satellite data for geophysical applications." Solar-Terrestrial Physics 5, no. 3 (September 30, 2019): 75–86. http://dx.doi.org/10.12737/stp-53201909.

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Model and computational algorithm for recovering the X-ray component of the solar spectrum based on GOES XL (0.1–0.8 nm), XS (0.05–0.4 nm or 0.05–0.3 nm) and SDO QD (0.1–7 nm) channels data are presented. The model based the Mewe approximation of emission from optically thin plasmas that presents a temperature-like spectrum. The possibility to present the result spectrum as a superposition of Mewe spectrums placed in the solar absorbing atmosphere at one optical depth for its temperature parameter energy is suggested in this paper. So the model is a variation of the multi-temperature approximation. Spectrum parameters are determined on the basis of support functions, approximation expressions for which are given in appendix.

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ESTAREMI, YOUSEF. "On the Composition of Conditional Expectation and Multiplication Operators." Kragujevac Journal of Mathematics 46, no. 6 (December 2022): 883–94. http://dx.doi.org/10.46793/kgjmat2206.883e.

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In this paper, ﬁrst we provide some necessary and suﬃcient conditions for quasi- normality and quasi- hyponormality of weighted conditional type operators. And then the spectrum, residual spectrum, point spectrum and spectral radius of weighted conditional type operators are computed. As an application, we give an equivalent conditions for weighted conditional type operators to be quasinilpotent. Also, some examples are provided to illustrate concrete applications of the main results.

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Moran, Timothy. "Applications of Sound Spectrum Analysis." Physics Teacher 45, no. 2 (February 2007): 93–95. http://dx.doi.org/10.1119/1.2432085.

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Xie, B. S., S. Y. Zhou, and L. X. Wu. "AN INTEGRATED MINERAL SPECTRAL LIBRARY USING SHARED DATA FOR HYPERSPECTRAL REMOTE SENSING AND GEOLOGICAL MAPPING." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLIII-B5-2020 (August 24, 2020): 69–75. http://dx.doi.org/10.5194/isprs-archives-xliii-b5-2020-69-2020.

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Abstract. Mineral spectral library (MSL) is the foundation of hyperspectral remote sensing, and a significant tool of storing and managing massive mineral spectral data to facilitate the matching or identifying of unknown rocks and minerals conveniently and fast. However, mineral spectral data are scattered and stored in different spectral libraries worldwide, which behave different spectral resolutions, mineral categories and measurement parameters, and hinder its application in field investigation, mineral identification, landcover identification and geological mapping. An integrated MSL using shared data is developed currently in Central South University, China, to improve the properties of MSL. We collected the shared spectral data and related information (e.g., mineral attribute data, spectrometer information, etc.) worldwide, performed data cleaning measures to retain the qualified spectral data and consolidated all the data in a common framework so as to establish a reliable and comprehensive dataset, and developed an integrated MSL for data management and diversified applications. The user can analysis the target spectrum with the spectrum absorption characteristic parameters, and match the measured spectral curve with the reference spectrum in the integrated MSL to find the most similar spectrum curve. It’s crucial to note that a new spectrum classifier was designed to limit the scope of matching for improving the efficiency of identification when the experimental sample lacks the specific information. The integrated MSL is developed in B/S and C/S website environments. A demonstration of functions of the integrated MSL and its preliminary applications are introduced in the article.

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Cheng, Andrew Y. S., Jianhua Zhu, and Michael C. Y. Pau. "Characterization of a Noncolinear Acousto-Optic Tunable Filter and its Resolution Enhancement as a Near-Infrared Spectrometer." Applied Spectroscopy 55, no. 3 (March 2001): 350–55. http://dx.doi.org/10.1366/0003702011951768.

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An automatic near-infrared (NIR) spectrometer based on a noncolinear acousto-optic tunable filter (AOTF) is constructed for high-speed spectrometry. Its initial spectral characteristics are studied systematically for application. The AOTF is a solid-state, rugged, compact, and high-speed device and can be readily used for spectral measurement applications, but some broadening and overlapping effects will occur when it is used for the measurement of a narrow-band spectrum. In order to correct the spectral distortion and obtain a fine spectrum, a new resolution enhancement procedure, which combines conventional Fourier self-deconvolution (FSD) with our optimized evaluation function and objective parameters determination, is used to resolve the band-broadened and band-overlapped spectral lines. The self-deconvolved spectrum is in good agreement with the fine spectrum measured by a high-resolution grating spectrometer. This is, to our knowledge, the first resolution enhancement of an AOTF spectrum by analytical and numerical operation.

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7

Nikolaeva, Vera, and Evgeny Gordeev. "SPAM: Solar Spectrum Prediction for Applications and Modeling." Atmosphere 14, no. 2 (January 21, 2023): 226. http://dx.doi.org/10.3390/atmos14020226.

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Solar Spectrum Prediction for Applications and Modeling (SPAM) is a new empirical model of solar X-ray, extreme ultraviolet and far ultraviolet radiation flux at the top of the Earth’s atmosphere. The model is based on 14 years of daily averaged TIMED spacecraft measurements from 2002 to 2016, when its sensors were regularly calibrated. We used a second-order parametrization of the irradiance spectrum by a single parameter—the F10.7 index—which is a reliable and consistently observed measure of solar activity. The SPAM model consists of two submodels for general and specific use. The first is the Solar-SPAM model of the photon energy flux in the first 190 spectral bands of 1 nm each, which can be used for a wide range of applications in different fields of research. The second model, Aero-SPAM, is designed specifically for aeronomic research and provides a photon flux for 37 specific wavelength intervals (20 wave bands and 16 separate spectral lines within the range of 5–105 nm, and an additional 121.5 nm Ly-alpha line), which play a major role in the photoionization of atmospheric gas particles. We provide the full set of parameterization coefficients that allows for the immediate implementation of the model for research and applications. In addition, we used the Aero-SPAM model to build a ready-to-use numerical application for calculating the photoionization rates of the main atmospheric components N2, O2, O, N and NO with known absorption and ionization cross sections.

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Pan, Mengguan, Baixiao Chen, and Minglei Yang. "A General Range-Velocity Processing Scheme for Discontinuous Spectrum FMCW Signal in HFSWR Applications." International Journal of Antennas and Propagation 2016 (2016): 1–13. http://dx.doi.org/10.1155/2016/2609873.

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Discontinuous spectrum signal which has separate subbands distributed over a wide spectrum band is a solution to synthesize a wideband waveform in a highly congested spectrum environment. In this paper, we present a general range-velocity processing scheme for the discontinuous spectrum-frequency modulated continuous wave (DS-FMCW) signal specifically. In range domain, we propose a simple time rearrangement operation which converts the range transform problem of the DS-FMCW signal to a general spectral estimation problem of nonuniformly sampled data. Conventional periodogram results in a dirty range spectrum with high sidelobes which cannot be suppressed by traditional spectral weighting. In this paper, we introduce the iterative adaptive approach (IAA) in the estimation of the range spectrum. IAA is shown to have the ability to provide a clean range spectrum. On the other hand, the discontinuity of the signal spectrum has little impact on the velocity processing. However, with the range resolution improved, the influence of the target motion becomes nonnegligible. We present a velocity compensation strategy which includes the intersweep compensation and in-sweep compensation. Our processing scheme with the velocity compensation is shown to provide an accurate and clean range-velocity image which benefits the following detection process.

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Fabila-Carrasco, John Stewart, and Fernando Lledó. "Covering Graphs, Magnetic Spectral Gaps and Applications to Polymers and Nanoribbons." Symmetry 11, no. 9 (September 14, 2019): 1163. http://dx.doi.org/10.3390/sym11091163.

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In this article, we analyze the spectrum of discrete magnetic Laplacians (DML) on an infinite covering graph G ˜ → G = G ˜ / Γ with (Abelian) lattice group Γ and periodic magnetic potential β ˜ . We give sufficient conditions for the existence of spectral gaps in the spectrum of the DML and study how these depend on β ˜ . The magnetic potential can be interpreted as a control parameter for the spectral bands and gaps. We apply these results to describe the spectral band/gap structure of polymers (polyacetylene) and nanoribbons in the presence of a constant magnetic field.

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Gil', Michael. "Spectrum localization of a perturbed operator in a strip and applications." Opuscula Mathematica 41, no. 3 (2021): 395–412. http://dx.doi.org/10.7494/opmath.2021.41.3.395.

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Let \(A\) and \(\tilde{A}\) be bounded operators in a Hilbert space. We consider the following problem: let the spectrum of \(A\) lie in some strip. In what strip the spectrum of \(\tilde{A}\) lies if \(A\) and \(\tilde{A}\) are "close"? Applications of the obtained results to integral operators and matrices are also discussed. In addition, we apply our perturbation results to approximate the spectral strip of a Hilbert-Schmidt operator by the spectral strips of finite matrices.

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Dissertations / Theses on the topic "SPECTRUM APPLICATIONS"

1

Bess, Philip K. "Spread spectrum applications in unmanned aerial vehicles." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1994. http://handle.dtic.mil/100.2/ADA281035.

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Lähetkangas, K. (Kalle). "Special applications and spectrum sharing with LSA." Doctoral thesis, Oulun yliopisto, 2019. http://urn.fi/urn:isbn:9789526223940.

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Abstract The commercial long-term evolution (LTE) networks of today offer fast and regionally wide access to the Internet and to the commercial applications and services at a reasonable price. At the same time, public safety (PS) users are still communicating with old-fashioned, second-generation voice and data services. Recently, the commercial LTE networks have been standardized to offer capabilities to mission-critical users. However, the commercial networks do not yet fully support the coverage requirements of the PS users. Moreover, the commercial infrastructure might be out of order in critical scenarios where PS actors are needed. Thus, the PS users require, for example, rapidly deployed LTE networks to support their own communication. This thesis studies the PS use of commercial operators' LTE networks and rapidly deployed closed LTE networks. The key tasks are to find out how to connect users seamlessly together between the different networks as well as finding out how the frequency planning is implemented. This thesis provides practical design solutions to guarantee network interoperability by connecting the networks as well as radio spectrum utilization solutions by licensed shared access (LSA). While the concept of LSA has been well developed, it has not been thoroughly investigated from the point of view of the PS actors, who have special requirements and should benefit from the concept. Herein, the alternatives for spectrum sharing between PS and commercial systems are discussed. Moreover, the thesis develops a specific LSA spectrum sharing system for the PS actors deploying their own network in scenarios where the commercial networks are insufficient. The solution is a robust LSA-based spectrum sharing mechanism. Note that PS actors also need to be able to utilize the spectrum when the LSA system is not available and when the commercial system has failed. Thus, this thesis proceeds on developing sensing methods for complementing LSA, where the sensing methods guarantee spectrum information for a rapidly deployed PS network. It is shown how PS actors can utilize available spectrum with a secondary spectrum licence. This is a good alternative to reserving the spectrum completely. The work assembles missing pieces of existing methods to ensure the functionality of the commercial and of the supporting rapidly deployed networks, both in terms of spectrum usage and application services
Tiivistelmä Kaupalliset long-term evolution (LTE) -verkot tarjoavat nopean, edullisen ja alueellisesti kattavan pääsyn Internettiin sekä laajaan valikoimaan sovelluksia. Samaan aikaan turvallisuustoimijat (public safety (PS) -toimijat) käyttävät vanhanaikaisia äänen sekä vaatimattoman datayhteyden tarjoavia verkkoja. LTE-verkot ovat kuitenkin äskettäin standardoitu tarjoamaan valmiudet myös toimintokriittiseen kommunikointiin. Toisaalta, kaupalliset LTE-verkot eivät vielä tarjoa esimerkiksi tarvittavaa alueellista kattavuutta PS-käyttäjille. Lisäksi, kaupalliset verkot saattavat olla epäkunnossa kriittisissä tilanteissa. Tämän vuoksi PS-toimijat tarvitsevat omia nopeasti pystytettäviä LTE-verkkoja tukemaan nykyaikaista viestintäänsä. Opinnäytetyössä tutkitaan näiden nopeasti pystytettävien LTE-verkkojen käyttöä kaupallisten LTE-verkkojen kanssa. Keskeiset tehtävät ovat eri verkkojen PS-toimijoiden saumaton yhdistäminen sekä verkkojen taajuusjaon toteuttaminen. Tämä opinnäytetyö tarjoaa käytännön ratkaisuja verkkojen yhteentoimivuuden takaamiseksi ja radiotaajuuksien jakoratkaisuja lisensoidun jaetun käyttöoikeuden licensed shared access (LSA) -metodin avulla. Vaikka LSA:n käsite on jo pitkälle kehitetty, sitä ei ole tutkittu perusteellisesti PS-toimijoiden näkökulmasta ottaen huomioon heidän erityisvaatimuksensa. Tässä työssä syvennytään näiltä osin LSA järjestelmään yhtenä vaihtoehtona taajuuksien saamiseksi nopeasti pystytettäville verkoille. Lisäksi työssä kehitetään robusti LSA-pohjainen taajuuksien jakamisjärjestelmä nopeasti pystytettäville verkoille tilanteissa, joissa kaupalliset verkot ovat riittämättömät. Huomaa, että PS-toimijoiden on pystyttävä hyödyntämään taajuuksia myös silloin, kun LSA-järjestelmän kaikki osat eivät ole käytettävissä ja kun kaupallinen LTE järjestelmä on alhaalla. Tätä varten opinnäytetyössä kehitetään LSA:ta täydentävä havainnointimenetelmä, jolla taataan taajuustiedot vapaista taajuuksista nopeasti pystytettäville verkoille, sekä näytetään, miten PS-toimijat voivat hyödyntää LSA:ta toissijaisen taajuuslisenssin avulla. Tämä on hyvä vaihtoehto radiospektrin varaamiseksi kokonaan. Työ kokoaa puuttuvia osia olemassa oleviin menetelmiin, jotta voidaan varmistaa kaupallisten verkkojen toimivuus PS-käyttäjille yhdessä niitä tukevien nopeasti pystytettävien verkkojen kanssa taajuuksien käytön ja sovelluspalvelujen osalta

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3

Petrini, Valeria <1984&gt. "Cognitive radio applications for enhanced spectrum efficiency." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5493/1/Petrini_Valeria_tesi.pdf.

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The aim of this thesis is the study of techniques for efficient management and use of the spectrum based on cognitive radio technology. The ability of cognitive radio technologies to adapt to the real-time conditions of its operating environment, offers the potential for more flexible use of the available spectrum. In this context, the international interest is particularly focused on the “white spaces” in the UHF band of digital terrestrial television. Spectrum sensing and geo-location database have been considered in order to obtain information on the electromagnetic environment. Different methodologies have been considered in order to investigate spectral resources potentially available for the white space devices in the TV band. The adopted methodologies are based on the geo-location database approach used either in autonomous operation or in combination with sensing techniques. A novel and computationally efficient methodology for the calculation of the maximum permitted white space device EIRP is then proposed. The methodology is suitable for implementation in TV white space databases. Different Italian scenarios are analyzed in order to identify both the available spectrum and the white space device emission limits. Finally two different applications of cognitive radio technology are considered. The first considered application is the emergency management. The attention is focused on the consideration of both cognitive and autonomic networking approaches when deploying an emergency management system. The cognitive technology is then considered in applications related to satellite systems. In particular a hybrid cognitive satellite-terrestrial is introduced and an analysis of coexistence between terrestrial and satellite networks by considering a cognitive approach is performed.

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4

Petrini, Valeria <1984&gt. "Cognitive radio applications for enhanced spectrum efficiency." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5493/.

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The aim of this thesis is the study of techniques for efficient management and use of the spectrum based on cognitive radio technology. The ability of cognitive radio technologies to adapt to the real-time conditions of its operating environment, offers the potential for more flexible use of the available spectrum. In this context, the international interest is particularly focused on the “white spaces” in the UHF band of digital terrestrial television. Spectrum sensing and geo-location database have been considered in order to obtain information on the electromagnetic environment. Different methodologies have been considered in order to investigate spectral resources potentially available for the white space devices in the TV band. The adopted methodologies are based on the geo-location database approach used either in autonomous operation or in combination with sensing techniques. A novel and computationally efficient methodology for the calculation of the maximum permitted white space device EIRP is then proposed. The methodology is suitable for implementation in TV white space databases. Different Italian scenarios are analyzed in order to identify both the available spectrum and the white space device emission limits. Finally two different applications of cognitive radio technology are considered. The first considered application is the emergency management. The attention is focused on the consideration of both cognitive and autonomic networking approaches when deploying an emergency management system. The cognitive technology is then considered in applications related to satellite systems. In particular a hybrid cognitive satellite-terrestrial is introduced and an analysis of coexistence between terrestrial and satellite networks by considering a cognitive approach is performed.

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5

Mariani, Andrea <1984&gt. "Spectrum Sensing Algorithms for Cognitive Radio Applications." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5615/2/Mariani_Andrea_SpectrumSensingforCognitiveRadio.pdf.

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Future wireless communications systems are expected to be extremely dynamic, smart and capable to interact with the surrounding radio environment. To implement such advanced devices, cognitive radio (CR) is a promising paradigm, focusing on strategies for acquiring information and learning. The first task of a cognitive systems is spectrum sensing, that has been mainly studied in the context of opportunistic spectrum access, in which cognitive nodes must implement signal detection techniques to identify unused bands for transmission. In the present work, we study different spectrum sensing algorithms, focusing on their statistical description and evaluation of the detection performance. Moving from traditional sensing approaches we consider the presence of practical impairments, and analyze algorithm design. Far from the ambition of cover the broad spectrum of spectrum sensing, we aim at providing contributions to the main classes of sensing techniques. In particular, in the context of energy detection we studied the practical design of the test, considering the case in which the noise power is estimated at the receiver. This analysis allows to deepen the phenomenon of the SNR wall, providing the conditions for its existence and showing that presence of the SNR wall is determined by the accuracy of the noise power estimation process. In the context of the eigenvalue based detectors, that can be adopted by multiple sensors systems, we studied the practical situation in presence of unbalances in the noise power at the receivers. Then, we shift the focus from single band detectors to wideband sensing, proposing a new approach based on information theoretic criteria. This technique is blind and, requiring no threshold setting, can be adopted even if the statistical distribution of the observed data in not known exactly. In the last part of the thesis we analyze some simple cooperative localization techniques based on weighted centroid strategies.

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Mariani, Andrea <1984&gt. "Spectrum Sensing Algorithms for Cognitive Radio Applications." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5615/.

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Future wireless communications systems are expected to be extremely dynamic, smart and capable to interact with the surrounding radio environment. To implement such advanced devices, cognitive radio (CR) is a promising paradigm, focusing on strategies for acquiring information and learning. The first task of a cognitive systems is spectrum sensing, that has been mainly studied in the context of opportunistic spectrum access, in which cognitive nodes must implement signal detection techniques to identify unused bands for transmission. In the present work, we study different spectrum sensing algorithms, focusing on their statistical description and evaluation of the detection performance. Moving from traditional sensing approaches we consider the presence of practical impairments, and analyze algorithm design. Far from the ambition of cover the broad spectrum of spectrum sensing, we aim at providing contributions to the main classes of sensing techniques. In particular, in the context of energy detection we studied the practical design of the test, considering the case in which the noise power is estimated at the receiver. This analysis allows to deepen the phenomenon of the SNR wall, providing the conditions for its existence and showing that presence of the SNR wall is determined by the accuracy of the noise power estimation process. In the context of the eigenvalue based detectors, that can be adopted by multiple sensors systems, we studied the practical situation in presence of unbalances in the noise power at the receivers. Then, we shift the focus from single band detectors to wideband sensing, proposing a new approach based on information theoretic criteria. This technique is blind and, requiring no threshold setting, can be adopted even if the statistical distribution of the observed data in not known exactly. In the last part of the thesis we analyze some simple cooperative localization techniques based on weighted centroid strategies.

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7

Jiang, Chen. "Applications of frequency hopping systems." Click to view the E-thesis via HKUTO, 2001. http://sunzi.lib.hku.hk/hkuto/record/B31241852.

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江晨 and Chen Jiang. "Applications of frequency hopping systems." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31241852.

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Jiang, Chen. "Applications of frequency hopping systems." Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk:8888/cgi-bin/hkuto%5Ftoc%5Fpdf?B22277729.

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Papadimitriou, Panayiotis D. "Code design based on metric-spectrum and applications." Texas A&M University, 2004. http://hdl.handle.net/1969.1/1365.

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We introduced nested search methods to design (n, k) block codes for arbitrary channels by optimizing an appropriate metric spectrum in each iteration. For a given k, the methods start with a good high rate code, say k/(k + 1), and successively design lower rate codes up to rate k/2^k corresponding to a Hadamard code. Using a full search for small binary codes we found that optimal or near-optimal codes of increasing length can be obtained in a nested manner by utilizing Hadamard matrix columns. The codes can be linear if the Hadamard matrix is linear and non-linear otherwise. The design methodology was extended to the generic complex codes by utilizing columns of newly derived or existing unitary codes. The inherent nested nature of the codes make them ideal for progressive transmission. Extensive comparisons to metric bounds and to previously designed codes show the optimality or near-optimality of the new codes, designed for the fading and the additive white Gaussian noise channel (AWGN). It was also shown that linear codes can be optimal or at least meeting the metric bounds; one example is the systematic pilot-based code of rate k/(k + 1) which was proved to meet the lower bound on the maximum cross-correlation. Further, the method was generalized such that good codes for arbitrary channels can be designed given the corresponding metric or the pairwise error probability. In synchronous multiple-access schemes it is common to use unitary block codes to transmit the multiple users information, especially in the downlink. In this work we suggest the use of newly designed non-unitary block codes, resulting in increased throughput eﬃciency, while the performance is shown not to be substantially sacriﬁced. The non-unitary codes are again developed through suitable nested searches. In addition, new multiple-access codes are introduced that optimize certain criteria, such as the sum-rate capacity. Finally, the introduction of the asymptotically optimum convolutional codes for a given constraint length, reduces dramatically the search size for good convolutional codes of a certain asymptotic performance, and the consequences to coded code-division multiple access (CDMA) system design are highlighted.

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Books on the topic "SPECTRUM APPLICATIONS"

1

de, Frutos José, and García Jorge, eds. Solid state spectroscopies: Basic principles and applications. River Edge, N.J: World Scientific, 2002.

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Bluston, H. S. Calculus applications of the spectrum / spectrum plus computers, with graphics. Bedford: Energy Consultancy, 1986.

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1952-, Creaser C. S., Davies, A. M. C. 1939-, and Royal Society of Chemistry (Great Britain), eds. Analytical applications of spectroscopy. London: Royal Society of Chemistry, 1988.

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C, Dixon Robert. Spread spectrum systems: With commercial applications. 3rd ed. New York: Wiley, 1994.

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Bluston, H. S. Geometric and computer graphics applications of the spectrum / spectrum plus computers. Bedford: Energy Consultancy, 1986.

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Spread spectrum and CDMA: Principles and applications. Chichester, West Sussex, England: John Wiley & Sons, 2005.

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Diem, Max. Modern vibrational spectroscopy and micro-spectroscopy: Theory, instrumentation, and biomedical applications. Chichester, West Sussex: John Wiley & Sons, Inc., 2015.

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Jue, Thomas. Biomedical applications of biophysics. New York: Humana Press, 2010.

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Hüfner, Stefan. Photoelectron spectroscopy: Principles and applications. 2nd ed. Berlin: Springer, 1996.

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Hüfner, Stefan. Photoelectron spectroscopy: Principles and applications. Berlin: Springer-Verlag, 1995.

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Book chapters on the topic "SPECTRUM APPLICATIONS"

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Borre, Kai. "Spectrum." In Plane Networks and their Applications, 127–38. Boston, MA: Birkhäuser Boston, 2001. http://dx.doi.org/10.1007/978-1-4612-0165-6_5.

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Efrat, Isaac. "Multifractal Spectrum and Laplace Spectrum." In Emerging Applications of Number Theory, 201–4. New York, NY: Springer New York, 1999. http://dx.doi.org/10.1007/978-1-4612-1544-8_7.

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Bretthorst, G. Larry. "Applications." In Bayesian Spectrum Analysis and Parameter Estimation, 117–77. New York, NY: Springer New York, 1988. http://dx.doi.org/10.1007/978-1-4684-9399-3_7.

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Teutsch, Michael, Angel D. Sappa, and Riad I. Hammoud. "Applications." In Computer Vision in the Infrared Spectrum, 59–75. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-01826-8_5.

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Takahashi, Hidetoshi, Yoko Kamio, and Shozo Tobimatsu. "Autism Spectrum Disorder." In Clinical Applications of Magnetoencephalography, 247–74. Tokyo: Springer Japan, 2016. http://dx.doi.org/10.1007/978-4-431-55729-6_13.

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Hassani, Hossein, and Rahim Mahmoudvand. "Applications of Singular Spectrum Analysis." In Singular Spectrum Analysis, 87–101. London: Palgrave Macmillan UK, 2018. http://dx.doi.org/10.1057/978-1-137-40951-5_3.

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Wang, Xiaochun, Yidong Li, Yi Jin, and Wei Wang. "Spectrum-Centric Differential Privacy for Hypergraph Spectral Clustering." In Parallel and Distributed Computing, Applications and Technologies, 3–14. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-5907-1_1.

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Yang, Wanshu, Yunxiao Zu, and Bin Hou. "The Research of Reactive Spectrum Handoff Algorithm Based on Spectrum Prediction." In Wireless Communications, Networking and Applications, 495–504. New Delhi: Springer India, 2015. http://dx.doi.org/10.1007/978-81-322-2580-5_45.

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Colonius, Fritz, and Wolfgang Kliemann. "Examples for the Spectrum." In Systems & Control: Foundations & Applications, 377–405. Boston, MA: Birkhäuser Boston, 2000. http://dx.doi.org/10.1007/978-1-4612-1350-5_10.

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Zhang, Zhitao. "Dancer–Fučik Spectrum." In Variational, Topological, and Partial Order Methods with Their Applications, 199–220. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-30709-6_7.

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Conference papers on the topic "SPECTRUM APPLICATIONS"

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Ishijima, Tatsuki, and Takahide Sakamoto. "Wideband Ultra-Flat Spectral Enhancement by Cascaded Phase Modulation on Frequency Comb Generated from Mach-Zehnder Modulator." In CLEO: Applications and Technology. Washington, D.C.: Optica Publishing Group, 2022. http://dx.doi.org/10.1364/cleo_at.2022.jth3a.24.

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We demonstrated efficient spectral enhancement of comb generator where cascaded phase-modulation was applied to comb generated from Mach-Zehnder Modulator; additionally enhancing spectra keeping spectral flatness without increasing modulators cascade scale. 25×25-GHz spectrum was experimentally generated.

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Armi, Nasrullah, M. Zuki Yusoff, and N. M. Saad. "Spectrum sensing and throughput performance in opportunistic spectrum access system." In Applications (ISWTA). IEEE, 2011. http://dx.doi.org/10.1109/iswta.2011.6089555.

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Kazakov, Vasily, Arseny Zhdanov, Mikhail Vaganov, and Oleg Moskaletz. "Power optical signals spectrum assessment using resonance spectral analysis method." In SPIE Optical Engineering + Applications, edited by Abdul A. S. Awwal and Khan M. Iftekharuddin. SPIE, 2012. http://dx.doi.org/10.1117/12.929129.

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Takayasu, Hideto, Shuhei Otsuka, and Takahide Sakamoto. "Super Agile High Resolution Spectrum Analyzer by Sampled Heterodyne System." In CLEO: Applications and Technology. Washington, D.C.: Optica Publishing Group, 2022. http://dx.doi.org/10.1364/cleo_at.2022.jth3a.20.

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We demonstrated a sampled heterodyne system that enables wide-bandwidth and high- resolution spectrum measurement with agile scanning despite of using a low-speed DSP. 5-GHz high-bandwidth spectral measurement with 0.006-pm resolution, 0.01-ms scanning speed was achieved.

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Menon, R., J. Yun, E. Gormley, and C. Immendorf. "SON for Government Spectrum Applications." In MILCOM 2013 - 2013 IEEE Military Communications Conference. IEEE, 2013. http://dx.doi.org/10.1109/milcom.2013.223.

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Chertock, Guy, and Christopher P. Heil. "Radio Spectrum for PTC Applications." In 2012 Joint Rail Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/jrc2012-74083.

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The wireless communications link is both a major and critical component of recently introduced PTC systems such as ACSES and I-ETMS. With PTC systems rapidly moving from optional to required, each agency planning on deploying a PTC system needs to properly secure wireless spectrum for its PTC operation. The RF spectrum in the U.S. is a scarce resource, availability and demand of which were not addressed by the U.S. Congress’ RSIA-2008; therefore, each railroad has to obtain sufficient spectrum for its PTC system as an individual party. There are certain key questions that must be answered during the spectrum acquisition process: What licenses are available and who are the potential sellers? Are there any interference or other ownership issues? How much does the desired spectrum cost? These and other questions must be considered as part of the Positive Train Control system’s design and deployment. This paper identifies spectrum parameters and options that must be considered as part of the successful deployment of wireless train control applications.

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Pavlinsky, M., R. Sunyaev, E. Churazov, A. Vikhlinin, S. Sazonov, M. Revnivtsev, V. Arefiev, et al. "Spectrum-RG astrophysical project." In SPIE Optical Engineering + Applications, edited by Stephen L. O'Dell and Giovanni Pareschi. SPIE, 2009. http://dx.doi.org/10.1117/12.837361.

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Zhao, Zhen-Ying, Jian-Zhong Cha, Meng-Zhou Zhu, and He Tang. "A New Diagnosis Method Based on State Spectrum and its Applications." In ASME 1991 Design Technical Conferences. American Society of Mechanical Engineers, 1991. http://dx.doi.org/10.1115/detc1991-0377.

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Abstract Based on the time series, a new concept of spectrum representing the system state, called State Spectrum, is developed through the analysis of the varying principles of self-regression coefficients in this paper. The physical explanation of the spectrum, the meanings of the spectrum’s longitudinal and transverse coordinate and the way to use them in the state recognition and fault diagnosis of mechanical devices have been discussed in details. some experiments have carried out and the results indicate that the proposed new approach is very promising in fault diagnosis of mechanical devices.

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Koksal, Aybora, Eren AkdemIr, and Ozgur Oruc. "Spectrum compression." In 2018 26th Signal Processing and Communications Applications Conference (SIU). IEEE, 2018. http://dx.doi.org/10.1109/siu.2018.8404263.

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Rothkopf, Alexander. "Bayesian techniques and applications to QCD." In XIII Quark Confinement and the Hadron Spectrum. Trieste, Italy: Sissa Medialab, 2019. http://dx.doi.org/10.22323/1.336.0026.

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Reports on the topic "SPECTRUM APPLICATIONS"

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Pawula, R. F. Applications of Differential Phase Statistics to Studies of C3 and Spread Spectrum Communications. Fort Belvoir, VA: Defense Technical Information Center, January 1985. http://dx.doi.org/10.21236/ada158815.

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Köck, Patrick, Arndt-Lukas Klaassen, M. Meyer, J. Kindler, and M. Kaess. Cannabinoids as therapeutics in child and adolescent psychiatry. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, March 2023. http://dx.doi.org/10.37766/inplasy2023.3.0017.

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Review question / Objective: P = Children and adolescents with psychiatric disorders; I = Cannabinoids as therapeutic product / medication; C = if randomised controlled trial, placebo; O = Evaluation of psychiatric symptoms (BDI for depression, symptom severity scales in case of ADHD or Autism Spectrum Disorders); S = Randomized controlled trials, controlled trials, case studies. Rationale: Cannabinoids especially THC and CBD have gained increasing scientific interest. Various studies have been published assessing the therapeutic applications of cannabinoids in psychiatry. Several systematic reviews have been published for application of cannabinoids in psychiatry for adults, however there is no recent systematic review assessing applications for child and adolescent psychiatry.

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Dyulicheva, Yulia Yu, Yekaterina A. Kosova, and Aleksandr D. Uchitel. he augmented reality portal and hints usage for assisting individuals with autism spectrum disorder, anxiety and cognitive disorders. [б. в.], November 2020. http://dx.doi.org/10.31812/123456789/4412.

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The augmented reality applications are effectively applied in education and therapy for people with special needs. We propose to apply the augmented reality portal as a special tool for the teachers to interact with people at the moment when a panic attack or anxiety happens in education process. It is expected that applying the augmented reality portal in education will help students with ASD, ADHD and anxiety disorder to feel safe at discomfort moment and teachers can interact with them. Our application with the augmented reality portal has three modes: for teachers, parents, and users. It gives the ability to organize personalized content for students with special needs. We developed the augmented reality application aimed at people with cognitive disorders to enrich them with communication skills through associations understanding. Applying the augmented reality application and the portal discovers new perspectives for learning children with special needs. The AR portal creates illusion of transition to another environment. It is very important property for children with ADHD because they need in breaks at the learning process to change activity (for example, such children can interact with different 3D models in the augmented reality modes) or environment. The developed AR portal has been tested by a volunteer with ASD (male, 21 years old), who confirmed that the AR portal helps him to reduce anxiety, to feel calm down and relaxed, to switch attention from a problem situation.

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Cohen, Yafit, Carl Rosen, Victor Alchanatis, David Mulla, Bruria Heuer, and Zion Dar. Fusion of Hyper-Spectral and Thermal Images for Evaluating Nitrogen and Water Status in Potato Fields for Variable Rate Application. United States Department of Agriculture, November 2013. http://dx.doi.org/10.32747/2013.7594385.bard.

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Potato yield and quality are highly dependent on an adequate supply of nitrogen and water. Opportunities exist to use airborne hyperspectral (HS) remote sensing for the detection of spatial variation in N status of the crop to allow more targeted N applications. Thermal remote sensing has the potential to identify spatial variations in crop water status to allow better irrigation management and eventually precision irrigation. The overall objective of this study was to examine the ability of HS imagery in the visible and near infrared spectrum (VIS-NIR) and thermal imagery to distinguish between water and N status in potato fields. To lay the basis for achieving the research objectives, experiments in the US and in Israel were conducted in potato with different irrigation and N-application amounts. Thermal indices based merely on thermal images were found sensitive to water status in both Israel and the US in three potato varieties. Spectral indices based on HS images were found suitable to detect N stress accurately and reliably while partial least squares (PLS) analysis of spectral data was more sensitive to N levels. Initial fusion of HS and thermal images showed the potential of detecting both N stress and water stress and even to differentiate between them. This study is one of the first attempts at fusing HS and thermal imagery to detect N and water stress and to estimate N and water levels. Future research is needed to refine these techniques for use in precision agriculture applications.

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Lopes, Joseph L. NSWC-PC Component of: Target Measurements to be Made as Part of a Full Spectrum Target Scattering Effort for MCM Applications. Fort Belvoir, VA: Defense Technical Information Center, September 2007. http://dx.doi.org/10.21236/ada541631.

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Mazzoni, Silvia, Nicholas Gregor, Linda Al Atik, Yousef Bozorgnia, David Welch, and Gregory Deierlein. Probabilistic Seismic Hazard Analysis and Selecting and Scaling of Ground-Motion Records (PEER-CEA Project). Pacific Earthquake Engineering Research Center, University of California, Berkeley, CA, November 2020. http://dx.doi.org/10.55461/zjdn7385.

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This report is one of a series of reports documenting the methods and findings of a multi-year, multi-disciplinary project coordinated by the Pacific Earthquake Engineering Research Center (PEER) and funded by the California Earthquake Authority (CEA). The overall project is titled “Quantifying the Performance of Retrofit of Cripple Walls and Sill Anchorage in Single-Family Wood-Frame Buildings,” henceforth referred to as the “PEER–CEA Project.” The overall objective of the PEER–CEA Project is to provide scientifically based information (e.g., testing, analysis, and resulting loss models) that measure and assess the effectiveness of seismic retrofit to reduce the risk of damage and associated losses (repair costs) of wood-frame houses with cripple wall and sill anchorage deficiencies as well as retrofitted conditions that address those deficiencies. Tasks that support and inform the loss-modeling effort are: (1) collecting and summarizing existing information and results of previous research on the performance of wood-frame houses; (2) identifying construction features to characterize alternative variants of wood-frame houses; (3) characterizing earthquake hazard and ground motions at representative sites in California; (4) developing cyclic loading protocols and conducting laboratory tests of cripple wall panels, wood-frame wall subassemblies, and sill anchorages to measure and document their response (strength and stiffness) under cyclic loading; and (5) the computer modeling, simulations, and the development of loss models as informed by a workshop with claims adjustors. This report is a product of Working Group 3 (WG3), Task 3.1: Selecting and Scaling Ground-motion records. The objective of Task 3.1 is to provide suites of ground motions to be used by other working groups (WGs), especially Working Group 5: Analytical Modeling (WG5) for Simulation Studies. The ground motions used in the numerical simulations are intended to represent seismic hazard at the building site. The seismic hazard is dependent on the location of the site relative to seismic sources, the characteristics of the seismic sources in the region and the local soil conditions at the site. To achieve a proper representation of hazard across the State of California, ten sites were selected, and a site-specific probabilistic seismic hazard analysis (PSHA) was performed at each of these sites for both a soft soil (Vs30 = 270 m/sec) and a stiff soil (Vs30=760 m/sec). The PSHA used the UCERF3 seismic source model, which represents the latest seismic source model adopted by the USGS [2013] and NGA-West2 ground-motion models. The PSHA was carried out for structural periods ranging from 0.01 to 10 sec. At each site and soil class, the results from the PSHA—hazard curves, hazard deaggregation, and uniform-hazard spectra (UHS)—were extracted for a series of ten return periods, prescribed by WG5 and WG6, ranging from 15.5–2500 years. For each case (site, soil class, and return period), the UHS was used as the target spectrum for selection and modification of a suite of ground motions. Additionally, another set of target spectra based on “Conditional Spectra” (CS), which are more realistic than UHS, was developed [Baker and Lee 2018]. The Conditional Spectra are defined by the median (Conditional Mean Spectrum) and a period-dependent variance. A suite of at least 40 record pairs (horizontal) were selected and modified for each return period and target-spectrum type. Thus, for each ground-motion suite, 40 or more record pairs were selected using the deaggregation of the hazard, resulting in more than 200 record pairs per target-spectrum type at each site. The suites contained more than 40 records in case some were rejected by the modelers due to secondary characteristics; however, none were rejected, and the complete set was used. For the case of UHS as the target spectrum, the selected motions were modified (scaled) such that the average of the median spectrum (RotD50) [Boore 2010] of the ground-motion pairs follow the target spectrum closely within the period range of interest to the analysts. In communications with WG5 researchers, for ground-motion (time histories, or time series) selection and modification, a period range between 0.01–2.0 sec was selected for this specific application for the project. The duration metrics and pulse characteristics of the records were also used in the final selection of ground motions. The damping ratio for the PSHA and ground-motion target spectra was set to 5%, which is standard practice in engineering applications. For the cases where the CS was used as the target spectrum, the ground-motion suites were selected and scaled using a modified version of the conditional spectrum ground-motion selection tool (CS-GMS tool) developed by Baker and Lee [2018]. This tool selects and scales a suite of ground motions to meet both the median and the user-defined variability. This variability is defined by the relationship developed by Baker and Jayaram [2008]. The computation of CS requires a structural period for the conditional model. In collaboration with WG5 researchers, a conditioning period of 0.25 sec was selected as a representative of the fundamental mode of vibration of the buildings of interest in this study. Working Group 5 carried out a sensitivity analysis of using other conditioning periods, and the results and discussion of selection of conditioning period are reported in Section 4 of the WG5 PEER report entitled Technical Background Report for Structural Analysis and Performance Assessment. The WG3.1 report presents a summary of the selected sites, the seismic-source characterization model, and the ground-motion characterization model used in the PSHA, followed by selection and modification of suites of ground motions. The Record Sequence Number (RSN) and the associated scale factors are tabulated in the Appendices of this report, and the actual time-series files can be downloaded from the PEER Ground-motion database Portal (https://ngawest2.berkeley.edu/)(link is external).

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Corriveau, Elizabeth, Travis Thornell, Mine Ucak-Astarlioglu, Dane Wedgeworth, Hayden Hanna, Robert Jones, Alison Thurston, and Robyn Barbato. Characterization of pigmented microbial isolates for use in material applications. Engineer Research and Development Center (U.S.), March 2023. http://dx.doi.org/10.21079/11681/46633.

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Organisms (i.e., plants and microorganisms) contain pigments that allow them to adapt and thrive under stressful conditions, such as elevated ultraviolet radiation. The pigments elicit characteristic spectral responses when measured by active and passive sensors. This research study focused on characterizing the spectral response of three organisms and how they compared to background spectral signatures of a complex environment. Specifically, spectra were collected from a fungus, a plant, and two pigmented bacteria, one of which is an extremophile bacterium. The samples were measured using Fourier transform infrared spectroscopy and dis-criminated using chemometric means. A top-down examination of the spectral data revealed that organisms could be discriminated from one an-other through principal component analysis (PCA). Furthermore, there was a strong distinction between the plant and the pigmented microorganisms. Spectral differences resulting in samples with the highest variance from the natural background were identified using PCA loading plots. The outcome of this work is a spectral library of pigmented biological candidates for coatings applications.

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Alchanatis, Victor, Stephen W. Searcy, Moshe Meron, W. Lee, G. Y. Li, and A. Ben Porath. Prediction of Nitrogen Stress Using Reflectance Techniques. United States Department of Agriculture, November 2001. http://dx.doi.org/10.32747/2001.7580664.bard.

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Commercial agriculture has come under increasing pressure to reduce nitrogen fertilizer inputs in order to minimize potential nonpoint source pollution of ground and surface waters. This has resulted in increased interest in site specific fertilizer management. One way to solve pollution problems would be to determine crop nutrient needs in real time, using remote detection, and regulating fertilizer dispensed by an applicator. By detecting actual plant needs, only the additional nitrogen necessary to optimize production would be supplied. This research aimed to develop techniques for real time assessment of nitrogen status of corn using a mobile sensor with the potential to regulate nitrogen application based on data from that sensor. Specifically, the research first attempted to determine the system parameters necessary to optimize reflectance spectra of corn plants as a function of growth stage, chlorophyll and nitrogen status. In addition to that, an adaptable, multispectral sensor and the signal processing algorithm to provide real time, in-field assessment of corn nitrogen status was developed. Spectral characteristics of corn leaves reflectance were investigated in order to estimate the nitrogen status of the plants, using a commercial laboratory spectrometer. Statistical models relating leaf N and reflectance spectra were developed for both greenhouse and field plots. A basis was established for assessing nitrogen status using spectral reflectance from plant canopies. The combined effect of variety and N treatment was studied by measuring the reflectance of three varieties of different leaf characteristic color and five different N treatments. The variety effect on the reflectance at 552 nm was not significant (a = 0.01), while canonical discriminant analysis showed promising results for distinguishing different variety and N treatment, using spectral reflectance. Ambient illumination was found inappropriate for reliable, one-beam spectral reflectance measurement of the plants canopy due to the strong spectral lines of sunlight. Therefore, artificial light was consequently used. For in-field N status measurement, a dark chamber was constructed, to include the sensor, along with artificial illumination. Two different approaches were tested (i) use of spatially scattered artificial light, and (ii) use of collimated artificial light beam. It was found that the collimated beam along with a proper design of the sensor-beam geometry yielded the best results in terms of reducing the noise due to variable background, and maintaining the same distance from the sensor to the sample point of the canopy. A multispectral sensor assembly, based on a linear variable filter was designed, constructed and tested. The sensor assembly combined two sensors to cover the range of 400 to 1100 nm, a mounting frame, and a field data acquisition system. Using the mobile dark chamber and the developed sensor, as well as an off-the-shelf sensor, in- field nitrogen status of the plants canopy was measured. Statistical analysis of the acquired in-field data showed that the nitrogen status of the com leaves can be predicted with a SEP (Standard Error of Prediction) of 0.27%. The stage of maturity of the crop affected the relationship between the reflectance spectrum and the nitrogen status of the leaves. Specifically, the best prediction results were obtained when a separate model was used for each maturity stage. In-field assessment of the nitrogen status of corn leaves was successfully carried out by non contact measurement of the reflectance spectrum. This technology is now mature to be incorporated in field implements for on-line control of fertilizer application.

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Tokarieva, Anastasiia V., Nataliia P. Volkova, Inesa V. Harkusha, and Vladimir N. Soloviev. Educational digital games: models and implementation. [б. в.], September 2019. http://dx.doi.org/10.31812/123456789/3242.

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Nowadays, social media, ICT, mobile technologies and applications are increasingly used as tools for communication, interaction, building up social skills and unique learning environments. One of the latest trends observed in education is an attempt to streamline the learning process by applying educational digital games. Despite numerous research data, that confirms the positive effects of digital games, their integration into formal educational contexts is still relatively low. The purpose of this article is to analyze, discuss and conclude what is necessary to start using games as an instructional tool in formal education. In order to achieve this aim, a complex of qualitative research methods, including semi-structured expert interviews was applied. As the result, the potential of educational digital games to give a unique and safe learning environment with a wide spectrum of build-in assistive features, be efficient in specific training contexts, help memorize studied material and incorporate different learning styles, as well as to be individually adaptable, was determined. At the same time, the need for complex approach affecting the administration, IT departments, educators, students, parents, a strong skill set and a wide spectrum of different roles and tasks a teacher carries out in a digital game-based learning class were outlined. In conclusion and as a vector for further research, the organization of Education Design Laboratory as an integral part of a contemporary educational institution was proposed.

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Shokair, I. R. Orthogonal spectra and cross sections: Application to optimization of multi-spectral absorption and fluorescence lidar. Office of Scientific and Technical Information (OSTI), September 1997. http://dx.doi.org/10.2172/653931.

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