Готові списки джерел за темами / Bank of filter trees

Добірка наукової літератури з теми "Bank of filter trees"

Автор: Grafiati
Опубліковано: 6 вересня 2023

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Статті в журналах з теми "Bank of filter trees"

1

Sablatash, M. "Designs and architectures of filter bank trees for spectrally efficient multi-user communications: review, modifications and extensions of wavelet packet filter bank trees." Signal, Image and Video Processing 2, no. 1 (September 18, 2007): 9–37. http://dx.doi.org/10.1007/s11760-007-0033-4.

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2

Gopinath, R. A., and C. S. Burrus. "Factorization approach to unitary time-varying filter bank trees and wavelets." IEEE Transactions on Signal Processing 43, no. 3 (March 1995): 666–80. http://dx.doi.org/10.1109/78.370621.

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3

Bąk, Artur, Jakub Segen, Kamil Wereszczyński, Pawel Mielnik, Marcin Fojcik, and Marek Kulbacki. "Detection of linear features including bone and skin areas in ultrasound images of joints." PeerJ 6 (March 15, 2018): e4411. http://dx.doi.org/10.7717/peerj.4411.

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Identifying the separate parts in ultrasound images such as bone and skin plays a crucial role in the synovitis detection task. This paper presents a detector of bone and skin regions in the form of a classifier which is trained on a set of annotated images. Selected regions have labels: skin or bone or none. Feature vectors used by the classifier are assigned to image pixels as a result of passing the image through the bank of linear and nonlinear filters. The filters include Gaussian blurring filter, its first and second order derivatives, Laplacian as well as positive and negative threshold operations applied to the filtered images. We compared multiple supervised learning classifiers including Naive Bayes, k-Nearest Neighbour, Decision Trees, Random Forest, AdaBoost and Support Vector Machines (SVM) with various kernels, using four classification performance scores and computation time. The Random Forest classifier was selected for the final use, as it gives the best overall evaluation results.
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4

Wieben, O., V. X. Afonso, and W. J. Tompkins. "Classification of premature ventricular complexes using filter bank features, induction of decision trees and a fuzzy rule-based system." Medical & Biological Engineering & Computing 37, no. 5 (September 1999): 560–65. http://dx.doi.org/10.1007/bf02513349.

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5

Dou, Hanjie, Changyuan Zhai, Liping Chen, Xiu Wang, and Wei Zou. "Comparison of Orchard Target-Oriented Spraying Systems Using Photoelectric or Ultrasonic Sensors." Agriculture 11, no. 8 (August 8, 2021): 753. http://dx.doi.org/10.3390/agriculture11080753.

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Анотація:
Orchard pesticide off-target deposition and drift cause substantial soil and water pollution, and other environmental pollution. Orchard target-oriented spraying technologies have been used to reduce the deposition and drift caused by off-target spraying and control environmental pollution to within an acceptable range. Two target-oriented spraying systems based on photoelectric sensors or ultrasonic sensors were developed. Three spraying treatments of young cherry trees and adult apple trees were conducted using a commercial sprayer with a photoelectric-based target-oriented spraying system, an ultrasonic-based target-oriented spraying system or no target-oriented spraying system. A rhodamine tracer was used instead of pesticide. Filter papers were fixed in the trees and on the ground. The tracer on the filter papers was washed off to calculate the deposition distribution in the trees and on the ground. The deposition data were used to evaluate the systems and pesticide off-target deposition achieved with orchard target-oriented sprayers. The results showed that the two target-oriented spraying systems greatly reduced the ground deposition compared to that caused by off-target spraying. Compared with that from off-target spraying, the ground deposition from photoelectric-based (trunk-based) and ultrasonic-based (canopy-based) target-oriented spraying decreased by 50.63% and 38.74%, respectively, for the young fruit trees and by 21.66% and 29.87%, respectively, for the adult fruit trees. The trunk-based target-oriented detection method can be considered more suitable for young trees, whereas the canopy-based target-oriented detection method can be considered more suitable for adult trees. The maximum ground deposition occurred 1.5 m from the tree trunk at the back of the tree canopy and was caused by the high airflow at the air outlet of the sprayer. A suitable air speed and air volume at the air outlet of the sprayer can reduce pesticide deposition on the ground.
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6

ARIVAZHAGAN, S., D. GNANADURAI, J. R. ANTONY VANCE, K. M. SAROJINI, and L. GANESAN. "IMPLEMENTATION OF ZERO TREE WAVELET CODERS IN DSP PROCESSOR." International Journal of Wavelets, Multiresolution and Information Processing 02, no. 01 (March 2004): 75–86. http://dx.doi.org/10.1142/s0219691304000366.

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With the fast evolution of Multimedia systems, Image compression algorithms are very much needed to achieve effective transmission and compact storage by removing the redundant information of the image data. Wavelet transforms have received significant attention, recently, due to their suitability for a number of important signal and image compression applications and the lapped nature of this transform and the computational simplicity, which comes in the form of filter bank implementations. In this paper, the implementation of image compression algorithms based on discrete wavelet transform such as embedded zero tree wavelet (EZW) coder, set partitioning in hierarchical trees coder without lists (SPIHT — No List) and packetizable zero tree wavelet (PZW) coder in DSP processor is dealt in detail and their performance analysis is carried out in terms of different compression ratios, execution timing and for different packet losses. PSNR is used as the criteria for the measurement of reconstructed image quality.
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7

Sharma, Manish, Jainendra Tiwari, Virendra Patel, and U. Rajendra Acharya. "Automated Identification of Sleep Disorder Types Using Triplet Half-Band Filter and Ensemble Machine Learning Techniques with EEG Signals." Electronics 10, no. 13 (June 25, 2021): 1531. http://dx.doi.org/10.3390/electronics10131531.

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A sleep disorder is a medical condition that affects an individual’s regular sleeping pattern and routine, hence negatively affecting the individual’s health. The traditional procedures of identifying sleep disorders by clinicians involve questionnaires and polysomnography (PSG), which are subjective, time-consuming, and inconvenient. Hence, an automated sleep disorder identification is required to overcome these limitations. In the proposed study, we have proposed a method using electroencephalogram (EEG) signals for the automated identification of six sleep disorders, namely insomnia, nocturnal frontal lobe epilepsy (NFLE), narcolepsy, rapid eye movement behavior disorder (RBD), periodic leg movement disorder (PLM), and sleep-disordered breathing (SDB). To the best of our belief, this is one of the first studies ever undertaken to identify sleep disorders using EEG signals employing cyclic alternating pattern (CAP) sleep database. After sleep-scoring EEG epochs, we have created eight different data subsets of EEG epochs to develop the proposed model. A novel optimal triplet half-band filter bank (THFB) is used to obtain the subbands of EEG signals. We have extracted Hjorth parameters from subbands of EEG epochs. The selected features are fed to various supervised machine learning algorithms for the automated classification of sleep disorders. Our proposed system has obtained the highest accuracy of 99.2%, 98.2%, 96.2%, 98.3%, 98.8%, and 98.8% for insomnia, narcolepsy, NFLE, PLM, RBD, and SDB classes against normal healthy subjects, respectively, applying ensemble boosted trees classifier. As a result, we have attained the highest accuracy of 91.3% to identify the type of sleep disorder. The proposed method is simple, fast, efficient, and may reduce the challenges faced by medical practitioners during the diagnosis of various sleep disorders accurately in less time at sleep clinics and homes.
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8

Edwar, E., and Achmad Munir. "Prototype of Dual DDS FMCW Transmitter for L-Band Synthetic Aperture Radar." Journal of Measurements, Electronics, Communications, and Systems 4, no. 1 (June 30, 2018): 8. http://dx.doi.org/10.25124/jmecs.v4i1.1694.

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One of the popular remote sensing technique is remote sensing using radar technology such as Synthetic Aperture Radar (SAR). In this paper, a compact SAR prototype transmitter was designed so it could be installed in small platform. This SAR transmitter was designed to generate a frequency modulated continuous wave (FMCW) using direct digital synthesizer (DDS) integrated with RF front end modules such as analog filter and power amplifier. The bandwidth of the radar spectrum is 10 MHz, and the carrier frequency used is 1.27 GHz. The L-Band has been chosen as the carrier signal in order to detect the target (trees). The payload was designed for aerial vehicle, hence the choice of components should be as small as possible. The FMCW-SAR transmitter was implemented by using DDS module AD9850 and integrated with another RF component. The FMCW-SAR transmitter produces the transmit power about -17.67 dBm.
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9

Zheng, Xianwei, Yuan Yan Tang, Jiantao Zhou, Jianjia Pan, Shouzhi Yang, Youfa Li, and Patrick S. P. Wang. "Multi-Level Downsampling of Graph Signals via Improved Maximum Spanning Trees." International Journal of Pattern Recognition and Artificial Intelligence 33, no. 03 (February 19, 2019): 1958005. http://dx.doi.org/10.1142/s0218001419580059.

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Graph signal processing (GSP) is an emerging field in the signal processing community. Novel GSP-based transforms, such as graph Fourier transform and graph wavelet filter banks, have been successfully utilized in image processing and pattern recognition. As a rapidly developing research area, graph signal processing aims to extend classical signal processing techniques to signals with irregular underlying structures. One of the hot topics in GSP is to develop multi-scale transforms such that novel GSP-based techniques can be applied in image processing or other related areas. For designing graph signal multi-scale frameworks, downsampling operations that ensuring multi-level downsampling should be specifically constructed. Among the existing downsampling methods in graph signal processing, the state-of-the-art method was constructed based on the maximum spanning tree (MST). However, when using this method for multi-level downsampling of graph signals defined on unweighted densely connected graphs, such as social network data, the sampling rates are not close to [Formula: see text]. This phenomenon is summarized as a new problem and called downsampling unbalance problem in this paper. Due to the unbalance, MST-based downsampling method cannot be applied to construct graph signal multi-scale transforms. In this paper, we propose a novel and efficient method to detect and reduce the downsampling unbalance generated by the MST-based method. For any given graph signal, we apply the graph density to construct a measurement of the downsampling unbalance generated by the MST-based method. If a graph signal has large unbalance possibility, the multi-level downsampling is conducted after the MST is improved. The experimental results on synthetic and real-world social network data show that downsampling unbalance can be efficiently detected and then reduced by our method.
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10

WANG, CHENG-YOU, ZHENG-XIN HOU, and AI-PING YANG. "BINARY TREE IMAGE CODING ALGORITHM BASED ON NON-SEPARABLE WAVELET TRANSFORM VIA LIFTING SCHEME." International Journal of Wavelets, Multiresolution and Information Processing 06, no. 05 (September 2008): 761–75. http://dx.doi.org/10.1142/s0219691308002641.

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In recent years, image coding based on wavelet transform has made rapid progress. In this paper, quincunx lifting scheme in wavelet transform is introduced and all phase interpolation filter banks which can be used in the lifting scheme for prediction and update are designed. Based on the basic idea of set partitioning in hierarchical trees (SPIHT) algorithm, the binary tree image coding algorithm is proposed. Just like SPIHT, the encoding algorithms can be stopped at any compressed file size or let run until the compressed file is a representation of a nearly lossless image. The experimental results on test images show that compared with SPIHT algorithm, the PSNRs of the proposed algorithm are superior by about 0.5 dB at the same bit rates and the subjective quality of reconstructed images is also better.
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Більше джерел

Дисертації з теми "Bank of filter trees"

1

Akpa, Marcellin. "Tree structure filter bank for wideband signal processing." Thesis, University of Ottawa (Canada), 1995. http://hdl.handle.net/10393/10407.

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Анотація:
A N-parallel branches maximally decimated filter bank is generally implemented using the polyphase components implementation. In this case, a N-th band lowpass filter is designed and its polyphase components are derived to constitute the branch 'subfilters.' This approach uses a N x N FFT matrix that will be the source of the complex (numbers) operations. Obviously, when the number of branches is equal to 2, the computations remain real. In a tree structure filter bank, the computations remain real with or without polyphase implementation. When the polyphase implementation is used, the branch signals at each stage are computed using a set of 2 x 2 FFT matrices leading to real computations. In this thesis, a new implementation approach based on the tree structured is proposed. The derivation of the structure is based on the equivalent parallel structure implementation of the tree structured filter bank. It uses the polyphase components of a given half-band lowpass filter (real coefficients) followed by a N x N Hadamard matrix. The computations, as in the original tree structured filter bank, remain real. A simplified version of the structure is a 'tree structure' followed by an N x N Hadamard matrix. A comparison between this new structure and the N parallel branch maximally decimated filter bank is made based on reconstruction error, computation complexity and processing delay.
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2

Bamberger, Roberto Hugo. "The directional filter bank : a multirate filter bank for the directional decomposition of images." Diss., Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/15346.

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3

De, Poret Frédéric. "Filter Bank Multi-Carrier Modulation." Thesis, KTH, Kommunikationsteori, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-168383.

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During the last years, multi-carrier modulations have raised a particular interest due to their high spectral efficiency and the possible assumption of flat frequency fading. The most broadly used multi-carrier modulation is the CP-OFDM. It allows very simple equalizations methods and MIMO transcoders which keep orthogonality between carrier waveforms. However, it does not allow any waveform flexibility and is not fully spectrally efficient. Due to the low waveform flexibility its performance is quite limited in scenarios like the frequency division multiple accesses. In order to improve its performance in this case, it is important to have a multi-carrier modulation with the possibility to have a waveform well localized in time and frequency. Grey analysis shows that the only way to get both full spectral efficiency and waveforms well localized in both time and frequency domain is to give up the orthogonality in the complex field. Using filter bank multi-carrier (FBMC) with Offset-QAM (OQAM) is one combination which achieves this task. In this thesis, we study this modulation, how it is possible to efficiently modulate and demodulate it but also the transcoder (pre-coder, equalizer or both) that can be used when transmitting through multi-tap and MIMO channels. Another modulation, based on FBMC with OQAM, cyclic offset-QAM (COQAM) tries to make a tradeoff between spectral efficiency and simplicity of the equalization and transcoding methods. In this thesis, FBMC based modulation schemes are tested through different scenario: unsynchronized multi-users, unsynchronized uplink, multitaps channels, SIMO, MISO and MIMO channels. COQAM is tested with some of these scenario when it is considered as relevant to test it.
Under senare år har intresset för multi-carrier modulering ökat på grund av dess höga spektrumeffektivitet under antagandet om slät frekvensfäding. Den vanligaste multicarrier moduleringen i praktiken är CP-OFDM. Denna modulering tillåter användning av enkla equalizeringsmetoder och MIMO transkodare vilket behåller ortogonalitet mellan vågformerna. Däremot tillåter den inte någon flexibilitet i val av vågform och är inte heller helt spektraleffektiv. På grund av inflexibilitet i val av vågform är dess prestanda begränsad under till exempel frekvensmultiplexing (FDMA). För att förbättra prestandan hos CP-OFDM ¨ar det viktigt att ha en modulering med möjlighet att en vågform begränsad i både tid och frekvens. Grey analys visar att det enda sättet att uppnå full spektrumeffektivitet, i kombination med vågformer som är väl begränsade i både tid och frekvens, är att ge upp ortogonaliteten i komplexa fältet. Filter Bank Multi-Carrier (FBMC) med Offset-QAM (OQAM) är ett alternativ som uppnår detta. I den här avhandlingen studeras just denna modulation, hur det är möjligt att göra effektiv modulation och demodulation, men också hur dess equalizer, pre-kodare och transkoder används vid multi-tap och MIMO-kanaler. En annan modulation, baserad på FBMC med OQAM, är cyclisk offset-QAM (COQAM). COQAM försöker göra avvägning mellan spektral effektivitet och enkelhet av utjämnings- och transkodrar metoder. I den här avhandlingen studeras både FBMC-baserade modulationer och COQAM i en rad olika scenarios: osynkroniserade multianvändare, osynkroniserad upplänk, flera vägar kanaler, SIMO, MISO och MIMO-kanaler.
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4

Kumar, Bhunesh. "Design of Harmonic Filters for Renewable Energy Applications." Thesis, Högskolan på Gotland, Institutionen för kultur, energi och miljö, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hgo:diva-1862.

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Анотація:
Harmonics are created by non-linear devices connected to the power system. Power system harmonics are multiples of the fundamental power system frequency and these harmonic frequencies can create distorted voltages and currents. Distortion of voltages and currents can affect the power system adversely causing power quality problems. Therefore, estimation of harmonics is of high importance for efficiency of the power system network. The problem of harmonic loss evaluation is of growing importance for renewable power system industry by impacting the operating costs and the useful life of the system components. Non-linear devices such as power electronics converters can inject harmonics alternating currents (AC) in the electrical power system. The number of sensitive loads that require ideal sinusoidal supply voltage for their proper operation has been increasing. To maintain the quality limits proposed by standards to protect the sensitive loads, it is necessary to include some form of filtering device to the power system. Harmonics also increases overall reactive power demanded by equivalent load. Filters have been devised to achieve an optimal control strategy for harmonic alleviation problems. To achieve an acceptable distortion, increase the power quality and to reduce the harmonics hence several three phase filter banks are used and connected in parallel. In this thesis, high order harmonics cases have been suppressed by employing variants of Butterworth, Chebyshev and Cauer filters. MATLAB/SIMULINK wind farm model was used to generate and analyze the different harmonics magnitude and frequency. High voltage direct current (HVDC) lines for an electrical grid that is more than50km far away wind farm generation plant was investigated for harmonics. These HVDC lines are also used in offshore wind farm plant. Investigated three-phase harmonics filters are shunt elements that are used in power systems for decreasing voltage distortion and for correcting the power factor. Renewable energy sources are not the stable source of energy generation like wind, solar and tidal e.t.c. Though they are secondary sources of generation and hard to connect with electrical grid. In near future the technique is to use the wave digital filter (WDF) or circulator-tree wave digital filter (CTWDF) for the renewable energy application can be employed to mitigate the harmonics. These WDF and CTWDF can b eused in HVDC lines and smart grid applications. A preliminary analysis is conducted for such a study.
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5

Rahimi, Siavash. "Oversampled perfect reconstruction filter bank transceivers." Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=123137.

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Multicarrier modulation (MCM) is an efficient transmission technique for high data rate wired and wireless communications, where the channel bandwidth is divided into several subchannels with their own carriers. There are many different possible realizations for MCM systems, but with no doubt, orthogonal frequency division multiplexing (OFDM) has been the most prevalent solution in many current applications and standards. However, due to its use of a rectangular prototype filter, channel impairments such as narrowband interference (NBI) and carrier frequency offset (CFO) can greatly deteriorate the performance of OFDM. Moreover, future telecommunication networks call for higher data rate, increased bandwidth efficiency and flexibility in handling unsynchronized users. Filter bank multicarrier (FBMC) techniques have recently attracted considerable attention within the research community as a venue to fulfill these needs and potentially outperform the established OFDM in application areas such as dynamic spectrum access (DSA) and cognitive radio.In this context, we first propose a novel method for the design of discrete Fourier transform (DFT) modulated oversampled perfect reconstruction filter bank (OPRFB), for transmultiplexing application in MCM systems. The perfect reconstruction (PR) property is enforced by employing a parametric class of paraunitary matrices to form the transmit/receive polyphase filters of the transceiver system. Specifically, the polyphase filters are obtained by cascading special types of paraunitary matrices characterized by a limited set of design parameters. To reduce the number of these parameters, three different factorization methods are employed and compared. Through the optimization of these design parameters, the stop-band energy of the subband filters can be minimized which leads to improved spectral containment. Numerical results show that the proposed scheme leads to a clear advantage not only in additive white Gaussian noise (AWGN) and frequency selective channels, but also in the presence of channel impairments such as NBI or CFO. In particular, it is found that a significant reduction in the bit error rate (BER) can be achieved by employing the proposed scheme. Secondly, still in the context of single-user systems, we derive a data-aided joint maximum likelihood (ML) estimator of the CFO and the channel impulse response (CIR) for OPRFB transceiver systems operating over frequency selective fading channels. Then, by exploiting the structural and spectral properties of these systems, we are able to considerably reduce the complexity of the proposed estimator through simplifications of the underlying likelihood function. The Cramer Rao bound (CRB) on the variance of unbiased CFO and CIR estimators is also derived. The performance of the proposed ML estimator is investigated by means of numerical simulations under realistic conditions with CFO and frequency selective fading channels. The effects of different pilot schemes on the estimation performance for applications over time-invariant and mobile time-varying channels are also examined. The results show that the proposed joint ML estimator exhibits an excellent performance, where it can accurately estimate the unknown CFO and CIR parameters for the various experimental setups under consideration.Our third and final contribution deals with the extension of these newly proposed estimators to the multi-user case. More specifically, we consider the joint estimation of the CFO and channel equalizer coefficients based on the ML principle in the uplink of multi-user OPRFB (MU-OPRFB) systems. The performance of the proposed joint ML estimator is examined for various subband allocation schemes by means of numerical simulations. Also, different distributions of pilots over time are considered and their effects are investigated over mobile time-varying channels.
La modulation à porteuses multiples (MCM) est une technique de transmission efficace pour les communications filaires et sans fil à débit de données élevé, où la bande passante est divisée en plusieurs sous-canaux ayant chacun leur propre fréquence porteuse. Il existe de multiples réalisations possibles pour les systèmes MCM, mais le multiplexage orthogonal par répartition en fréquence (OFDM) est la solution la plus répandue dans les applications et standards présentement en vigueur. Toutefois, en raison de l'utilisation de filtres de synthèse et d'analyse rectangulaires, certaines imperfections causées par le canal de transmission, tels que les interférences à bande étroite (NBI) et le décalage de la fréquence porteuse (CFO), peuvent dégrader de manière significative les performances d'OFDM. Par ailleurs, les futurs réseaux de télécommunication nécessiteront des débits de transmission plus élevés, une plus grande efficacité de la bande passante et plus de flexibilité dans la gestion d'utilisateurs multiples non synchronisés. Les techniques de bancs de filtres à porteuses multiples (FBMC) ont récemment attiré l'attention de nombreux chercheurs.Dans ce contexte, nous proposons tout d'abord une nouvelle méthode pour la conception des bancs de filtres sur-échantillonnés à reconstruction parfaite (OPRFB) basés sur la modulation par transformation de Fourier discrète (DFT), pour les applications de transmultiplexage dans les systèmes MCM. La propriété de reconstruction parfaite (PR) est assurée par l'utilisation d'une famille paramétrique de matrices para-unitaires dans la réalisation des filtres polyphasés utilisés pour la transmission et la réception des données. L'optimisation des paramètres de conception pour la méthode choisie a pour but de minimiser l'énergie des filtres de synthèse et d'analyse dans la bande de coupure, ce qui conduit à une amélioration du confinement spectral. Les résultats d'analyse et de simulations montrent que les bancs de filtres OPRFB donnent lieu à un avantage marqué. En particulier, on constate une réduction significative du taux d'erreurs binaires (BER) lors de la transmission de données au moyen de la structure OPRFB proposée.Notre deuxième contribution porte donc sur le développement et l'analyse d'un nouvel estimateur conjoint des paramètres CFO et la réponse impulsionnelle du canal (CIR) basé sur le principe de la vraisemblance maximale (ML) et utilisant une séquence d'entraînement connue, toujours dans un contexte à usager unique. La borne de Cramer Rao (CRB) sur la variance des estimateurs non-biaisés des paramètres CFO et CIR est également dérivée. La performance du nouvel estimateur ML est soumise à l'étude par l'entremise de simulations numériques dans des conditions réalistes, soit en présence de CFO et de canaux à évanouissements en fréquence sélectifs. Les effets de différents motifs de tonalités pilotes sur la performance de l'estimation sont également. Les résultats démontrent l'excellente performance du nouvel estimateur ML conjoint proposé, qui peut déterminer avec une grande précision les paramètres CFO et CIR inconnus dans les différentes configurations expérimentales soumises à l'étude.Notre troisième et dernière contribution traite de l'extension de ce nouvel estimateur ML au cas d'usagers multiple. Plus précisément, nous considérons l'estimation conjointe du CFO et des coefficients CIR basée sur le principe ML dans la liaison montante des systèmes de transmission OPRFB multi-usagers (MU-OPRFB). Suite à son extension au cas multi-usagers, la performance de l'estimateur ML conjoint est examinée à l'aide de simulations numériques pour différents schémas d'allocation des sous-bandes entre les usagers. En outre, différentes distributions de tonalités pilotes dans le temps sont prises en compte et leurs effets sont étudiés sur des canaux radio mobiles variant dans le temps. Le potentiel d'application du nouvel estimateur ML aux systèmes multi-usagers est démontré.
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6

Parra, Paulo Mario. "Filter-bank transforms with exact inverses." Diss., The University of Arizona, 2003. http://hdl.handle.net/10150/289984.

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Анотація:
Uniformly sampled filter-bank transforms and their inverses are introduced and the conditions to obtain perfect reconstruction upon inversion are explored. It is shown that perfect reconstruction requires both filter addition and multiplication and the necessary and sufficient conditions for these operations are given. Examples indicate how to use the conditions to construct perfect-reconstruction synthesis filters from a given set of analysis filters. Additionally, an iterative scheme is presented that achieves exact inversion to an arbitrary accuracy. The methods to obtain synthesis filters are applied to discretizations of the continuous wavelet transform using both finite and infinite impulse response filters. If exact reconstruction is not a requisite, it is possible to improve imperfect-reconstruction filter banks so that their inverse is closer to the input signal. Two methods to achieve such improvement are described. To better understand the discretizations, one has to look at the continuous case. Therefore the discrete-time filter-bank transforms definitions are extended to continuous-time signal processing. It is shown that the Gabor and continuous wavelet transforms are special cases of the continuous-time extension. The methods introduced in the discrete-time case are used to derive all the linear time-invariant synthesis functions of these two transforms. A straightforward generalization of the Gabor and wavelet transforms generates filter banks whose bandwidths can vary arbitrarily with center frequency. These filters are used to create a cochlear transform, i.e., a "mixed" transform that behaves like a Gabor transform at low center frequencies and like a continuous wavelet transform at high center frequencies. The methodology described in this thesis is implemented in a set of algorithms whose complete documentation are given in chapter 4.
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Taheri, Sohail. "Performance improvement of filter bank multicarrier systems." Thesis, University of Surrey, 2018. http://epubs.surrey.ac.uk/846262/.

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Ever increasing demands for higher data rates in mobile communication present an ultimate challenge to deliver a consistent service experience to users. Filter bank multicarrier (FBMC) systems with very low out of band radiation facilitate aggregation of non-adjacent bands and asynchronous transmissions to provide the service enhancement. The primary research objective in these systems is followed by the contributions provided in this thesis. First of all, filter bank based multicarrier systems using fast convolution approach are investigated. We show that by applying FFT-based convolution without overlapped processing, the circular distortion can be discarded as a part of orthogonal interference term. The advantages of this property are spectral efficiency enhancement in the system and complexity reduction. The results show spectral efficiency enhancement by up to 15\% compared to conventional FBMC, while the complexity of the system is roughly half of conventional FBMC. Secondly, two channel estimation methods for MIMO-FBMC are proposed. The first one is a preamble-based approach aiming to reduce the preamble duration overhead and peak to average power ratio compared to the existing methods. The results confirm that this method outperforms the existing methods in terms of the mentioned parameters with up to 55\% in the overhead reduction. The second approach is a comb-based method with avoiding the contamination of pilots with symbol interference and saving time-frequency resources compared to existing methods. The results show a comparable performance of this method with is OFDM counterpart. Finally, we investigate the problems of transmitting complex symbols in FBMC systems. The challenge in these systems is designing appropriate filters to minimize the interference between adjacent subcarriers while maintaining the Nyquist property of the filter. We exploit fractional shift of the filtered symbols to compensate the deviation from the Nyquist property. The results show the proposed filter provides approximately 3 dB improvement of signal to interference ratio compared to the conventional filters.
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8

Larsson, Mats. "Development of a Digital Universal Filter Bank." Thesis, Uppsala universitet, Signaler och System, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-307929.

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This is a master's thesis project, which is a part of the Master Programme in Electrical Engineering at Uppsala university. When developing a product or performing measurements, it is sometimes necessary to remove some content of a signal. This might be due to an interfering source that has to be filtered out, or that only a specific frequency interval is of interest. In such a case, it would be practical if a universal frequency selective filter was available and easy to use. In this thesis, a platform for implementing different frequency selective digital filters is developed. Through a user interface, parameters such as sampling frequency, filter order, type of filter and cutoff frequencies are set by the user. This provides a platform which is easy to configure in order to run one or multiple IIR or FIR filters in various constellations. By combining different filters, a wide variety of frequency responses can be obtained. A prototype is constructed, which allows the user to connect up to two input signals and retrieve up to two output signals. The filter bank is programmed in C and implemented in a 32-bit microcontroller, base on the ARM architecture. To get a reliable prototype, a printed circuit board is designed and manufactured. To protect the electronics from external stress, a cover is designed and 3D-printed. The filter design algorithms and the algorithm used when running the filter bank gives satisfying results. The capacity of the filter bank can be increased by refining the filtering algorithm. By improving the hardware, noise generated by the electronics can be decreased. The filter bank has a really good potential to become a very useful tool.
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9

Demmer, David. "OFDM Precoding for Filter-Bank based Waveforms." Thesis, Paris, CNAM, 2019. http://www.theses.fr/2019CNAM1237/document.

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De nouveaux usages des systèmes de communications sans fils, tels que les réseaux de capteurs ou les voitures autonomes, ont émergé au cours des dernières années. Ces usages sont fondamentalement différents des applications haut-débit actuelles des réseaux cellulaires. La future technologie mobile, la 5G New Radio, introduit donc le concept de numérologie du signal afin de pouvoir satisfaire aux besoin hétérogènes des multiples applications supportées. En effet en supportant différentes numérologies de signaux, l'allocation temps/fréquence des signaux devient plus flexible et le signal transmis peut être adapté en conséquence. Cependant, supporte simultanément différentes numérologies génère de l'interférence et donc distord les signaux. Les filtrages spatiaux, comme la formation de faisceaux, est envisagée en 5G pour limiter l'interférence générée mais pour les communications au-dessus de 6 GHz. Il n'y a cependant pas de solutions proposées pour mes communications en-dessous de 6 GHz. Dans ce travail, des techniques d'atténuation des lobes secondaires sont étudiées pour faciliter le multiplexage des services pour les communications sous 6 GHz. L’interférence entre-utilisateurs est alors contrôlée mais la bande est également mieux utilisée. Une solution innovante, combinant bancs de filtres et orthogonalité complexe, est proposée. L'orthogonalité complexe est garanti grâce à un précodage OFDM qui remplace le précodage OQAM communément utilisé. De plus, le système développé, le Block-Filtered OFDM, utilise un récepteur 5G classique ce qui garantit la retro-compatibilité avec les techniques déjà déployée. Le modèle du BF-OFDM est entièrement décrit et adapté aux normes des réseaux mobiles. De plus, de multiples méthodes de conception des filtres prototypes sont proposées afin de mieux répondre aux besoins des systèmes. La forme d'onde étudiée est également comparée avec les autres solutions de l'état de l'art sur des scénarios d'étude classiques mais également adaptés aux nouveaux enjeux des technologies sans fils
New use cases for wireless communications recently emerged ranging from massive sensor networks to connected cars. These applications highly differ from typical signals supported by already deployed mobile technologies, which are mainly high data rate pipes. The forthcoming generation of mobile technology, 5G New Radio, introduces the concept of signal numerology so as to properly serve the requirements of the diverse applications it will support. Indeed by considering different numerologies, the time/frequency signal allocation is made more flexible which allows to shape the transmitted signal according to its needs. However, multiplexing signals with different numerologies generates interference and therefore signal distortion. Spatial filtering, such as beamforming, is envisioned for 5G above 6-GHz communications to limit inter-user interference. However, this issue still holds for sub-6 GHz systems where spatial filtering is not considered in 5G.In this work, we consider side lobe rejection techniques to ease service multiplexing in sub-6 GHz bands. Not only it provides inter-user interference mitigation but it also improves the bandwidth use efficiency in bands where frequency is a scarce resource. A novel solution, mixing filter-bank for confined spectrum and complex orthogonality for a straightforward re-use of known-how 4G/5G techniques, is proposed. The complex orthogonality is restored thanks to an OFDM precoding substituting the commonly used Offset-QAM signaling which limits the orthogonality to the real field. Moreover, the proposed solution, named Block-Filtered Orthogonal Frequency Division Multiplexing (BFOFDM), relies on a simple 5G receiver scheme which makes it backward compatible with already deployed technologies.The BF-OFDM system model is fully described and adapted to cellular standards. Besides, different prototype filter designs methods are proposed to either improve the intrinsic interference attenuation or to better confined the spectrum of the transmitted signal. Last but not least, the proposed waveform will be compared with state-of-the-art solutions for both typical and 5G oriented evaluation scenarios such as multi-service coexistence
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10

Ha, Hoang Kha Electrical Engineering &amp Telecommunications Faculty of Engineering UNSW. "Linear phase filter bank design by convex programming." Publisher:University of New South Wales. Electrical Engineering & Telecommunications, 2008. http://handle.unsw.edu.au/1959.4/43268.

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Digital filter banks have found in a wide variety of applications in data compression, digital communications, and adaptive signal processing. The common objectives of the filter bank design consist of frequency selectivity of the individual filters and perfect reconstruction of the filter banks. The design problems of filter banks are intrinsically challenging because their natural formulations are nonconvex constrained optimization problems. Therefore, there is a strong motivation to cast the design problems into convex optimization problems whose globally optimal solutions can be efficiently obtained. The main contributions of this dissertation are to exploit the convex optimization algorithms to design several classes of the filter banks. First, the two-channel orthogonal symmetric complex-valued filter banks are investigated. A key contribution is to derive the necessary and sufficient condition for the existence of complex-valued symmetric spectral factors. Moreover, this condition can be expressed as linear matrix inequalities (LMIs), and hence semi-definite programming (SDP) is applicable. Secondly, for two-channel symmetric real-valued filter banks, a more general and efficient method for designing the optimal triplet halfband filter banks with regularity is developed. By exploiting the LMI characterization of nonnegative cosine polynomials, the semi-infinite constraints can be efficiently handled. Consequently, the filter bank design is cast as an SDP problem. Furthermore, it is demonstrated that the resulting filter banks are applied to image coding with improved performance. It is not straightforward to extend the proposed design methods for two-channel filter banks to M-channel filter banks. However, it is investigated that the design problem of M-channel cosine-modulated filter banks is a nonconvex optimization problem with the low degree of nonconvexity. Therefore, the efficient semidefinite relaxation technique is proposed to design optimal prototype filters. Additionally, a cheap iterative algorithm is developed to further improve the performance of the filter banks. Finally, the application of filter banks to multicarrier systems is considered. The condition on the transmit filter bank and channel for the existence of zero-forcing filter bank equalizers is obtained. A closed-form expression of the optimal equalizer is then derived. The proposed filter bank transceivers are shown to outperform the orthogonal frequency-division multiplexing (OFDM) systems.
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Книги з теми "Bank of filter trees"

1

Lin, Yuan-Pei. Filter bank transceivers for OFDM and DMT systems. Cambridge: Cambridge University Press, 2011.

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2

Schuler, Thomas M. Seed bank response to prescribed fire in the central Appalachians. Newtown Square, PA: United States Dept. of Agriculture, Forest Service, Northern Research Station, 2010.

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3

H, Bircher Warda, ed. Encyclopedia of fruit trees and edible flowering plants in Egypt and the subtropics. Cairo: American University in Cairo Press, 2000.

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4

Assembly, Canada Legislature Legislative. Bill: An act to amend chapter fifty-four of the Consolidated statutes for Upper Canada, in relation to the felling of trees on road allowances. Quebec: Thompson, Hunter, 2003.

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5

Chai, Li, and Jingxin Zhang. System Approach to Filter Bank Frames. Taylor & Francis Group, 2019.

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6

Lin, Yuan-Pei, P. P. Vaidyanathan, and See-May Phoong. Filter Bank Transceivers for OFDM and DMT Systems. Cambridge University Press, 2011.

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7

Lin, Yuan-Pei, P. P. Vaidyanathan, and See-May Phoong. Filter Bank Transceivers for OFDM and DMT Systems. Cambridge University Press, 2010.

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8

Lin, Yuan-Pei, P. P. Vaidyanathan, and See-May Phoong. Filter Bank Transceivers for OFDM and DMT Systems. Cambridge University Press, 2015.

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9

Lin, Yuan-Pei, P. P. Vaidyanathan, and See-May Phoong. Filter Bank Transceivers for Ofdm and Dmt Systems. Cambridge University Press, 2010.

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10

Fleming, Ronald John. Modern filter-controllers for bank-to-turn CLOS guidance. 1987.

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Частини книг з теми "Bank of filter trees"

1

Niu, Panpan, Xiangyang Wang, and Mingyu Lu. "A Novel Pyramidal Dual-Tree Directional Filter Bank Domain Color Image Watermarking Algorithm." In Information and Communications Security, 158–72. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-25243-3_13.

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2

Koldovský, Zbyněk, Petr Tichavský, and Jiří Málek. "Subband Blind Audio Source Separation Using a Time-Domain Algorithm and Tree-Structured QMF Filter Bank." In Latent Variable Analysis and Signal Separation, 25–32. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-15995-4_4.

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3

Yin, Hui, Yuanhao Gong, and Guoping Qiu. "Guided Filter Bank." In Lecture Notes in Networks and Systems, 783–92. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-80119-9_50.

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4

Nissel, Ronald, and Markus Rupp. "Filter Bank Multicarrier Modulation." In Multiple Access Techniques for 5G Wireless Networks and Beyond, 63–92. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-92090-0_3.

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5

Thiagarajan, Jayaraman J., and Andreas Spanias. "Analysis Subband Filter Bank." In Analysis of the MPEG-1 Layer III (MP3) Algorithm Using MATLAB, 13–23. Cham: Springer International Publishing, 2012. http://dx.doi.org/10.1007/978-3-031-01518-2_2.

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6

Ling, Wing-kuen, and Peter Kwong-Shun Tam. "Set of Decimators for Tree Structure Filter Banks." In Wavelet Analysis and Its Applications, 336–40. Berlin, Heidelberg: Springer Berlin Heidelberg, 2001. http://dx.doi.org/10.1007/3-540-45333-4_42.

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7

Farhang, Arman, Nicola Marchetti, and Behrouz Farhang-Boroujeny. "Filter Bank Multicarrier for Massive MIMO." In Signal Processing for 5G, 67–89. Chichester, UK: John Wiley & Sons, Ltd, 2016. http://dx.doi.org/10.1002/9781119116493.ch4.

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8

Sruthi, S., and J. Dhoulath Beegum. "Filter Bank Modulation in Massive MIMO Scenario." In Lecture Notes in Networks and Systems, 335–43. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-0146-3_31.

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9

Ryan, Øyvind. "The Polyphase Representation of Filter Bank Transforms." In Springer Undergraduate Texts in Mathematics and Technology, 255–82. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-01812-2_7.

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10

GuoYing, Sun, Li YunJie, Gao MeiGuo, and Hu GuangLi. "Realization of Filter Bank Based on FPGA." In Recent Advances in Computer Science and Information Engineering, 829–34. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-25769-8_115.

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Тези доповідей конференцій з теми "Bank of filter trees"

1

Wang, Luyun, Ronggang Qi, Lu Wang, and Guoan Bi. "Serialization of tree structured Quadrature Mirror Filter bank." In TENCON 2016 - 2016 IEEE Region 10 Conference. IEEE, 2016. http://dx.doi.org/10.1109/tencon.2016.7848470.

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2

Akpa and Steenaart. "N-parallel filter bank equivalent to tree structure." In Proceedings of Canadian Conference on Electrical and Computer Engineering CCECE-94. IEEE, 1994. http://dx.doi.org/10.1109/ccece.1994.405796.

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3

Anurag, S., and A. Kumar. "Simple iterative design technique for tree structured non-uniform filter bank." In 2012 1st International Conference on Recent Advances in Information Technology (RAIT). IEEE, 2012. http://dx.doi.org/10.1109/rait.2012.6194547.

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4

Mahesh, R., A. P. Vinod, B. Y. Tan, and Edmund M. K-Lai. "A tree-structured non-uniform filter bank for multi-standard wireless receivers." In 2009 IEEE International Symposium on Circuits and Systems - ISCAS 2009. IEEE, 2009. http://dx.doi.org/10.1109/iscas.2009.5117723.

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5

Narendar, M., A. P. Vinod, A. S. Madhukumar, and Anoop Kumar Krishna. "An algorithm for spectrum sensing in cognitive radio using tree-structured filter bank." In 2010 17th International Conference on Telecommunications. IEEE, 2010. http://dx.doi.org/10.1109/ictel.2010.5478782.

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6

Bui, Ha H., and Truong T. Nguyen. "Image denoising using the non-uniform directional filter bank and hidden markov tree." In 2006 IEEE 12th Digital Signal Processing Workshop & 4th IEEE Signal Processing Education Workshop. IEEE, 2006. http://dx.doi.org/10.1109/dspws.2006.265409.

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7

Tseng, Chien-Cheng, and Su-Ling Lee. "A Graph Signal De-Noising Method Using Spanning Tree and Graph Filter Bank." In 2019 IEEE International Conference on Consumer Electronics - Taiwan (ICCE-TW). IEEE, 2019. http://dx.doi.org/10.1109/icce-tw46550.2019.8991974.

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8

Wang, Jinhua, Songhe Feng, and Qingsong Bao. "Pyramidal dual-tree directional filter bank based exposure fusion for two complementary images." In 2010 10th International Conference on Signal Processing (ICSP 2010). IEEE, 2010. http://dx.doi.org/10.1109/icosp.2010.5655887.

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9

Rhee Man Kil, Young-Ik Kim, and Geon Hyoung Lee. "A noise-robust front-end based on tree-structured filter-bank for speech recognition." In Proceedings of the IEEE-INNS-ENNS International Joint Conference on Neural Networks. IJCNN 2000. Neural Computing: New Challenges and Perspectives for the New Millennium. IEEE, 2000. http://dx.doi.org/10.1109/ijcnn.2000.859376.

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10

Baradarani, Aryaz, and Jonathan Wu. "Moving object segmentation using the 9/7–10/8 dual-tree complex filter bank." In 2008 19th International Conference on Pattern Recognition (ICPR). IEEE, 2008. http://dx.doi.org/10.1109/icpr.2008.4761620.

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Звіти організацій з теми "Bank of filter trees"

1

Phoong, See-May, and P. P. Vaidyanathan. One- and Two-Level Filter Bank Convolvers. Fort Belvoir, VA: Defense Technical Information Center, March 1993. http://dx.doi.org/10.21236/ada268965.

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2

Tuqan, Jamal, and P. P. Vaidyanathan. Optimum Low Cost Two Channel IIR Orthonormal Filter Bank,. Fort Belvoir, VA: Defense Technical Information Center, April 1997. http://dx.doi.org/10.21236/ada323660.

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3

Shelley, John, Christopher Haring, and Nathan Chrisman. Evaluation of cedar tree revetments for bank stabilization at the Locust Creek Conservation Area, Missouri : quantifying bank erosion volumes from preproject to postfailure. Engineer Research and Development Center (U.S.), December 2022. http://dx.doi.org/10.21079/11681/46144.

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The US Army Corps of Engineers Regional Sediment Management (RSM) program funded research to assess the longevity and effectiveness of cedar tree revetments for sediment reduction. Between 1988 and 1997, the Missouri Department of Conservation (MDC) constructed multiple cedar tree revetments, plantings, and a grade-control structure at an experimental stream management area on Locust Creek within the Locust Creek Conservation Area (LCCA). For the first few years, MDC also replaced missing trees as needed. MDC monitored these sites with photographs and cross sections until 2004. This study evaluated bank stability on Locust Creek from 1970 to 2019 using aerial imagery, lidar, ground surveys, and a December 2019 site visit to estimate the areal change in streambanks and the volume of sediment eroded over the years. Based on their dates of construction, the project compared preproject, with-project, and postfailure conditions at each site. The project included cedar tree revetments, other hardwood revetments, plantings, and a grade-control structure. This research found a 50% to 64% reduction in erosion for approximately 14 years. As of December 2019, all tree revetments had failed, and banks were bare and steep. The grade-control structure remained intact and continued to stabilize bed and banks immediately upstream.
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4

Lee, W. S., Victor Alchanatis, and Asher Levi. Innovative yield mapping system using hyperspectral and thermal imaging for precision tree crop management. United States Department of Agriculture, January 2014. http://dx.doi.org/10.32747/2014.7598158.bard.

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Original objectives and revisions – The original overall objective was to develop, test and validate a prototype yield mapping system for unit area to increase yield and profit for tree crops. Specific objectives were: (1) to develop a yield mapping system for a static situation, using hyperspectral and thermal imaging independently, (2) to integrate hyperspectral and thermal imaging for improved yield estimation by combining thermal images with hyperspectral images to improve fruit detection, and (3) to expand the system to a mobile platform for a stop-measure- and-go situation. There were no major revisions in the overall objective, however, several revisions were made on the specific objectives. The revised specific objectives were: (1) to develop a yield mapping system for a static situation, using color and thermal imaging independently, (2) to integrate color and thermal imaging for improved yield estimation by combining thermal images with color images to improve fruit detection, and (3) to expand the system to an autonomous mobile platform for a continuous-measure situation. Background, major conclusions, solutions and achievements -- Yield mapping is considered as an initial step for applying precision agriculture technologies. Although many yield mapping systems have been developed for agronomic crops, it remains a difficult task for mapping yield of tree crops. In this project, an autonomous immature fruit yield mapping system was developed. The system could detect and count the number of fruit at early growth stages of citrus fruit so that farmers could apply site-specific management based on the maps. There were two sub-systems, a navigation system and an imaging system. Robot Operating System (ROS) was the backbone for developing the navigation system using an unmanned ground vehicle (UGV). An inertial measurement unit (IMU), wheel encoders and a GPS were integrated using an extended Kalman filter to provide reliable and accurate localization information. A LiDAR was added to support simultaneous localization and mapping (SLAM) algorithms. The color camera on a Microsoft Kinect was used to detect citrus trees and a new machine vision algorithm was developed to enable autonomous navigations in the citrus grove. A multimodal imaging system, which consisted of two color cameras and a thermal camera, was carried by the vehicle for video acquisitions. A novel image registration method was developed for combining color and thermal images and matching fruit in both images which achieved pixel-level accuracy. A new Color- Thermal Combined Probability (CTCP) algorithm was created to effectively fuse information from the color and thermal images to classify potential image regions into fruit and non-fruit classes. Algorithms were also developed to integrate image registration, information fusion and fruit classification and detection into a single step for real-time processing. The imaging system achieved a precision rate of 95.5% and a recall rate of 90.4% on immature green citrus fruit detection which was a great improvement compared to previous studies. Implications – The development of the immature green fruit yield mapping system will help farmers make early decisions for planning operations and marketing so high yield and profit can be achieved.
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