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Letteratura scientifica selezionata sul tema "Signal stations"

Autore: Grafiati

Pubblicato: 29 luglio 2024

Ultima modifica: 30 luglio 2024

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Articoli di riviste sul tema "Signal stations"

Mayowa, Gbalaja. "Assessment of Radio Waves Propagation Pattern from Radio Stations in Lokoja and Okene, Kogi State, Nigeria". Advanced Journal of Science, Technology and Engineering 2, n. 1 (30 novembre 2022): 78–92. http://dx.doi.org/10.52589/ajste-au9cs6sp.

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Okene, Lokoja and their environs have been experiencing radio signal distortions and have been of great concern to the citizens due to bad quality signals and signal attenuation increase. This study assesses the patterns of radio wave propagation from five radio stations in Lokoja and Okene, Kogi State, Nigeria. Equipment, a field strength metre was used to measure signal strengths and quality of radio signals. Six locations in both Lokoja, Okene and the environs were selected for each radio station. The approximate distances between the transmitting and receiving antennas were determined. Thirty-five locations were measured inclusive of the five radio stations and the six selected positions. Three locations in Okene and another three locations in Lokoja were used. Thereafter, calculations of the signal wavelengths of each radio station and the free space path-loss of signals were calculated at the positions. Factors such as reflections by buildings, mountains and vegetation cover, refractions by the rivers, streams, rainfall and absorption of the human abdomen were looked into at such areas as likely causes of signal attenuation. Good locations to site FM radio stations were determined from the results. The approximate distances from the stations to establish booster stations in order to receive news adequately were also determined.

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Jin, Jionghua. "Individual Station Monitoring Using Press Tonnage Sensors for Multiple Operation Stamping Processes". Journal of Manufacturing Science and Engineering 126, n. 1 (1 febbraio 2004): 83–90. http://dx.doi.org/10.1115/1.1643749.

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In multiple operation stamping processes, a press tonnage signal measured by press tonnage sensors installed on press linkages/uprights, is the summation of die forces at all stations. Different from the current practice of using a whole cycle of press tonnage signals to monitor the compound condition of all stations, this paper proposes a new method to use the partitioned monitoring segments of press tonnage signals to monitor individual station conditions. For this purpose, a generic signal segmentation principle is proposed, and the Hotelling T2 control charts are developed with consideration of the interactions among stations. A real case study of a doorknob stamping process is provided to demonstrate analysis procedures and effectiveness of the developed methodology.

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Parshutkin, Andrey, Dmitry Levin e Aleksey Galandzovskiy. "Simulation model of radar data processing in a station network under signal-like interference". Information and Control Systems, n. 6 (16 gennaio 2020): 22–31. http://dx.doi.org/10.31799/1684-8853-2019-6-22-31.

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Introduction: Radar stations, when tracking targets in a complex interference environment, form not only target marks but also false marks. A well-developed theory and technique of noise stability is not useful under signal-like interference caused by re-reflections, multi-path propagation or retransmission of the probing signals. The reliability of radar information processing under signal-like interference can be improved by joint processing of data from several spaced posts in a radar station network. Purpose: development of а simulation model which would allow you to estimate the effectiveness of radar target selection by spatial rating of its measured positions, with joint processing of the radar information obtained from two spaced radar stations. Results: We have implemented the framework of joint radar data processing for target selection in a radar station network under signal-like interference. The selection is based on using the information about the coincidence of radar target coordinates measured by spaced radar stations. A simulation model is developed to estimate the target selection probability under signal-like interference during the joint processing of data from two spaced radar stations, by analyzing the coincidence of the measured coordinates of the targets. It has been found out how the target selection probability depends on the noise interference power and the average density of false marks in the range channels of two spaced radar stations. Practical relevance: The simulation results demonstrate the possibility of increasing the range of radar target detection by network radar stations under signal-like interference, and the efficiency of using the information about coincidence of radar target coordinates measured by spaced radar stations, which is better than using only the signal features of radar target selection on the background of false marks.

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Chang, Sang-Yoon, Kyungmin Park, Jonghyun Kim e Jinoh Kim. "Flying Base Station Channel Capacity Limits: Dependent on Stationary Base Station and Independent of Positioning". Electronics 13, n. 12 (7 giugno 2024): 2234. http://dx.doi.org/10.3390/electronics13122234.

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Flying base stations, also known as aerial base stations, provide wireless connectivity to the user and utilize their aerial mobility to improve communication performance. Flying base stations depend on traditional stationary terrestrial base stations for connectivity, as stationary base stations act as the gateway to the backhaul/cloud via a wired connection. We introduce the flying base station channel capacity to build on the Shannon channel capacity, which quantifies the upper-bound limit of the rate at which information can be reliably transmitted using the communication channel regardless of the modulation and coding techniques used. The flying base station’s channel capacity assumes aerial mobility and ideal positioning for maximum channel capacity. Therefore, the channel capacity limit holds for any digital and signal processing technique used and for any location or positioning of the flying base station. Because of its inherent reliance on the stationary terrestrial base station, the flying base station channel capacity depends on the stationary base station’s parameters, such as its location and SNR performance to the user, in contrast to previous research, which focused on the link between the user and the flying base station without the stationary base station. For example, the beneficial region (where there is a positive flying base station capacity gain) depends on the stationary base station’s power and channel SNR in addition to the flying base station’s own transmission power and whether it has full duplex vs. half-duplex capability. We jointly study the mobility and the wireless communications of the flying base station to analyze its position, channel capacity, and beneficialness over the stationary terrestrial base station (capacity gain). As communication protocols and implementations for flying base stations undergo development for next-generation wireless networking, we focus on information-theoretical analyses and channel capacity to inform future research and development in flying base station networking.

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FABO, Peter, Pavol NEJEDLÍK, Michal KUBA, Milan ONDERKA e Dušan PODHORSKÝ. "Applicability of the ultra-high radio frequency band (UHF) for hydrometeor detection by phase difference method". Contributions to Geophysics and Geodesy 51, n. 2 (29 giugno 2021): 109–27. http://dx.doi.org/10.31577/congeo.2021.51.2.1.

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Hydrometeors (rain, fog and ice crystals) affect the transmission of electromagnetic signals. Previous research showed that alterations in the signal (amplitude and phase) are affected by the composition of the atmosphere, e.g. the presence of hydrometeors. The majority of hydrometeorological detecting methods are based on the attenuation of electromagnetic signals as they penetrate the atmosphere. Novel methods based on monitoring of parameters of the signal appeared in recent time. This article presents the first results from our investigation of how hydrometeors affect the phase differences in signals transmitted by BTS stations. Cell phone operators transmit electromagnetic signals in the 1 GHz frequency band. This paper describes a novel concept of how phase differences between two signals arriving at two different antennas can be used to detect hydrometeors. Although the described concept is assumed to be independent from the signal strength, the analysed signal must be detectable. The primary advantage of the proposed passive method is that the signal is almost ubiquitous and does not require demodulation. In densely populated areas, the network of BTS stations reaches a spatial density of 1 station per 1 km2 which gives excellent opportunity to use the signal for detection purposes.

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Turner, Ross J., Anya M. Reading e Matt A. King. "Separation of tectonic and local components of horizontal GPS station velocities: a case study for glacial isostatic adjustment in East Antarctica". Geophysical Journal International 222, n. 3 (30 maggio 2020): 1555–69. http://dx.doi.org/10.1093/gji/ggaa265.

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SUMMARY Accurate measurement of the local component of geodetic motion at GPS stations presents a challenge due to the need to separate this signal from the tectonic plate rotation. A pressing example is the observation of glacial isostatic adjustment (GIA) which constrains the Earth’s response to ice unloading, and hence, contributions of ice-covered regions such as Antarctica to global sea level rise following ice mass loss. While both vertical and horizontal motions are of interest in general, we focus on horizontal GPS velocities which typically contain a large component of plate rotation and a smaller local component primarily relating to GIA. Incomplete separation of these components introduces significant bias into estimates of GIA motion vectors. We present the results of a series of tests based on the motions of GPS stations from East Antarctica: (1) signal separation for sets of synthetic data that replicate the geometric character of non-separable, and separable, GIA-like horizontal velocities; and (2) signal separation for real GPS station data with an appraisal of uncertainties. For both synthetic and real motions, we compare results where the stations are unweighted, and where each station is areal-weighted using a metric representing the inverse of the spatial density of neighbouring stations. From the synthetic tests, we show that a GIA-like signal is recoverable from the plate rotation signal providing it has geometric variability across East Antarctica. We also show that areal-weighting has a very significant effect on the ability to recover a GIA-like signal with geometric variability, and hence on separating the plate rotation and local components. For the real data, assuming a rigid Antarctic plate, fitted plate rotation parameters compare well with other studies in the literature. We find that 25 out of 36 GPS stations examined in East Antarctica have non-zero local horizontal velocities, at the 2σ level, after signal separation. We make the code for weighted signal separation available to assist in the consistent appraisal of separated signals, and the comparison of likely uncertainty bounds, for future studies.

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Shi, Xinlei, Xiaofei Zhang e Haowei Zeng. "Direct Position Determination of Non-Circular Sources for Multiple Arrays via Weighted Euler ESPRIT Data Fusion Method". Applied Sciences 12, n. 5 (28 febbraio 2022): 2503. http://dx.doi.org/10.3390/app12052503.

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In recent years, direct position determination (DPD) with multiple arrays for non-circular (NC) signals is a hot topic to research. Conventional DPD techniques with spectral peak search methods have high computational complexity and are sensitive to the locations of the observation stations. Besides, there will be loss when the signal propagates in the air, which leads to different received signal-to-noise ratios (SNRs) for each observation station. To attack the problems mentioned above, this paper derives direct position determination of non-circular sources for multiple arrays via weighted Euler estimating signal parameters viarotational invariance techniques (ESPRIT) data fusion (NC-Euler-WESPRIT) method. Firstly, elliptic covariance information of NC signals and Euler transformation are used to extend the received signal. Secondly, ESPRIT is applied to avoid the high-dimensional spectral function search problem of each observation station. Then, we combine the information of all observation stations to construct a spectral function without complex multiplication to reduce the computational complexity. Finally, the data of each observation station is weighted to compensate for the projection error. The consequence of simulation indicates that the proposed NC-Euler-WESPRIT algorithm not only improves the estimation performance, but also greatly reduces the computational complexity compared with subspace data fusion (SDF) technology and NC-ESPRIT algorithm.

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Wei, S. S., Xiao Qing Zeng, T. Shen, Y. J. Chen e W. Y. Wang. "A Method for Correction Ranging of Train Based on RSSI". Applied Mechanics and Materials 743 (marzo 2015): 484–90. http://dx.doi.org/10.4028/www.scientific.net/amm.743.484.

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In the railway operation, it's significant to obtain the distances between trains. A method based on RSSI for ranging and correction is proposed in this paper. The devices include a number of base stations installed along railways. The front train would send an active signal to the nearby base station N, when it transmits power signal to the following one. The following train also gives an active signal to its nearest base station 1 which would be enabled to gain signal from station N. The error of per meter of every section would be calculated by the known distance between base stations. The distances between trains could be corrected by the error and the loss of RSSI signal. The experiment result shows that this method is effective.

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Xi, Yanpeng, Jian Liu e Wenhao Zhao. "SATCOM Earth Station Arrays Anti-Jamming Based on MVDR Algorithm". Applied Sciences 13, n. 14 (19 luglio 2023): 8337. http://dx.doi.org/10.3390/app13148337.

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In modern life, a large amount of information is transmitted through satellites. The anti-jamming ability of satellite communication earth stations is the basis for ensuring the smooth flow of information. In the case that multiple small earth stations cannot communicate due to jamming, the minimum variance distortionless response (MVDR) algorithm based on reflector antenna array is proposed. Firstly, the gain expression of satellite communication earth station antenna is derived, and the mathematical model of the received signal of the reflector antenna array is established. Then, the MVDR beamforming algorithm based on the reflector antenna is proposed and applied to the satellite communication earth station reflector antenna array, and the anti-jamming capability of the reflector antenna array using this algorithm is analyzed through simulation. The simulation results show that the earth station reflector antenna array using MVDR algorithm can effectively achieve array gain of the direction of the satellite signal, suppress the jamming signals, increase the output signal to interference plus noise ratio (SINR) of the reflector antenna array, and increase the output signal to jamming plus noise ratio with the increase in the number of snapshots.

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Enice Sanyaolu, Modupe, e Sanyaolu Olufemi. "Seasonal and latitudinal variations of surface radio refractivity over Nigeria". Indonesian Journal of Electrical Engineering and Computer Science 28, n. 3 (7 ottobre 2022): 1548. http://dx.doi.org/10.11591/ijeecs.v28.i3.pp1548-1553.

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Refractivity is a significant challenge of radio signal propagation. As it often distorts or leads to loss of signals. The seasonal and latitudinal variations of surface refractivity at three Nigerian tropospheric Observatory stations in Nigeria, namely Port-Harcourt, Lagos, and Makurdi, are presented in this paper. Values of monthly averages of pressure, temperature, relative humidity, and water vapour from the stations were used to compute surface refractivity at each station. The results show that the values of surface refractivity increase from the arid region in the north to the coastal area in the south. There was an increase in the values of surface radio refractivity from the minimum value of about 332.83 N-units at Makurdi station to a maximum value of 386.69 N-units at Lagos station. Seasonal variations are seen to be caused by weather conditions. The values of the surface refractivity increased significantly in the wet season and reduced in the dry season. It also shows that the values of surface radio refractivity are affected by the meteorological components mentioned above. The result of this study is needed for effective planning of good signal reception in these stations.

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Più fonti

Tesi sul tema "Signal stations"

Qasim, Muhammad, e Ali Chaudhry Majid. "Signal Processing on Ambric Processor Array : Baseband processing in radio base stations". Thesis, Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-1660.

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The advanced signal processing systems of today require extreme data throughput and low power consumption. The only way to accomplish this is to use parallel processor architecture.

The aim of this thesis was to evaluate the use of parallel processor architecture in baseband signal processing. This has been done by implementing three demanding algorithms in LTE on Ambric Am2000 family Massively Parallel Processor Array (MPPA). The Ambric chip is evaluated in terms of computational performance, efficiency of the development tools, algorithm and I/O mapping.

Implementations of Matrix Multiplication, FFT and Block Interleaver were performed. The implementation of algorithms shows that high level of parallelism can be achieved in MPPA especially on complex algorithms like FFT and Matrix multiplication. Different mappings of the algorithms are compared to see which best fit the architecture.

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Chaufray, Jean-Marie. "Détection et démodulation de stations de base dans le réseau UMTS". Marne-la-Vallée, 2003. http://www.theses.fr/2003MARN0161.

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Cette thèse qui s’est déroulée dans le cadre d’un contrat CIFRE entre Thales Communications et l’Université de Marne-la-Vallée s’inscrit dans le contexte d’un projet européen. Les travaux effectués concernent la détection et la démodulation de stations de base d’un réseau UMTS-FDD, à l’aide d’une antenne munie de plusieurs capteurs. Dans une première partie, nous avons développé et testé une procédure pour la détection et la synchronisation des stations de base basée sur des algorithmes exploitant les dimensions spatiale et temporelle des signaux reçus. La deuxième partie est consacrée à l’estimation du canal de propagation. Nous avons développé un estimateur des statistiques du second ordre du canal de propagation et nous l’avons appliqué à l’amélioration de l’estimateur de canal classique. Enfin, dans la troisième partie, après avoir présenté plusieurs structures de démodulation, nous avons évalué leurs performances asymptotiques théoriques et nous les avons comparées par des simulations dans un environnement réaliste

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Gollbo, Simon, e Adam Sköld. "Base stations for communication in obstructed environments". Thesis, Uppsala universitet, Signaler och System, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-255243.

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The purpose of this project was to produce signal relay stations that could receive information via 2.4 GHz radio and relay the information to a designated target station. If a relay station was located outside of signal range for the target station it was supposed to utilize other relay stations to transfer the information to the target station, so called multi-hop. The would-be application of the relay stations was orienteering. When an orienteer punches a checkpoint the signal stations would relay information of who punched the control, when it was punched and the checkpoint that was punched to the speaker tower in the goal area. The work resulted in prototypes which fulfilled the statement of purpose and was tested at an orienteering competition with satisfactory results. The performance of the prototypes was tested and found adequate for the would-be application.

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Law, Eugene. "TECHNIQUE FOR DETERMINING THE POWER FLUX DENSITY OF INTERFERING SIGNALS AT TELEMETRY RECEIVING STATIONS". International Foundation for Telemetering, 2005. http://hdl.handle.net/10150/604814.

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ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada
This paper will present techniques for accurately measuring the power flux density (PFD) of interfering signals at telemetry receiving stations. The solar power flux density is measured daily by radio astronomers and will be used as a calibration signal. The electromagnetic spectrum is being used more intensely as time marches on so being familiar with interference measurement techniques is becoming more important because more interfering signals are present.

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ERTUNCAY, DENIZ. "Temporal and spatial analysis of near fault stations in terms of impulsive behavior". Doctoral thesis, Università degli Studi di Trieste, 2020. http://hdl.handle.net/11368/2961198.

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Increasing number of seismic stations located in close proximity to active faults allows analysis of seismic signals that are recorded in near fault regions. Unique seismic signals, called “impulsive” or “pulse shaped” signals, are captured in velocity waveforms in numerous large magnitude earthquakes. In such waveforms, the earthquake is recorded as a one or several long period high amplitude signals. Long period signals are important in engineering seismology due to their large loads on structures. Ground motion prediction equations and design codes fail to capture the amplitudes in long periods of the impulsive signals. In this thesis nature of impulsive signals and their spatial distribution in near fault regions are investigated. To do that two different algorithm are developed in order to distinguish impulsive signals from non-impulsive signals. Moreover, the probability of the pulse shaped signal occurrence is estimated. In order to investigate the impulsive signals, near fault records from major crustal earthquakes are merged into a dataset. It contains waveforms that are coming from well known seismogenic zones. Waveforms in the dataset are also analyzed by implementing several previous studies to make comparison. The first pulse shaped signal classification algorithm is developed using wavelet analysis. Wavelet analysis decomposes the signal into time-frequency domain which provides the energy variation with time and frequency. The wavelet power spectrum of velocity waveforms are analyzed by using Ricker and Morlet wavelets. A threshold of minimum amplitude is applied. A comparison is made between the total energy of a signal and the energy of the time incidence where peak ground velocity is measured. Furthermore time incidence where maximum spectral energy is located in time is also taken into consideration. Energy ratios are used for determination of impulsive signals. It is found that a Ricker wavelet explains the features of the impulsive part of the velocity waveforms more accurately than the Morlet wavelet. It can measure the period of the pulse and the phase shift of the impulsive parts of the waveform. Spectral features of the impulsive signals are also captured successfully using a Ricker wavelet. The second classification algorithm uses convolutional neural networks. In order to train the convolutional neural networks, synthetic impulsive signals are created. A model is developed using real non-impulsive velocity waveforms from the dataset and synthetic impulsive waveforms. Impulsive signals are manually labeled as impulsive or non-impulsive. The trained model is run on the real manually picked impulsive signals of the dataset and the performance of the convolutional neural network, the wavelet method and various previously published methods are benchmarked. The convolutional neural networks approach correctly identifies almost 97% of the impulsive signals. Accuracy rate of the model is superior than other models. In order to understand the probability of the impulsive signals on earthquakes, a multi-variate Bayes classifier method is implemented on the dataset. Various information about the fault, earthquake and station are analyzed and 3 parameters that are correlated with the impulsive signals are used for the probability calculations. Probability models are developed for normal, reverse and strike slip faults. The validity of this model is tested on the data set. Developed models can provide pulse probability distributions without requiring earthquake-specific parameters. A relation between the period of the pulses and the moment magnitude is also developed.

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Ghorabi, Moncef. "Vitesses de groupe mesurée en deux stations du réseau GEOSCOPE et régionalisation de la structure globale du manteau supérieur". Paris 7, 1985. http://www.theses.fr/1985PA07F056.

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Analyse des données du mode fondamental des ondes de Love et de Rayleigh, obtenues aux deux premières stations du réseau, SSB et PCR, pendant les années 1982 à 1984. Calcul des courbes de dispersion en vitesse de groupe sur les trajets directs et inverses et quelques trains d'ordre supérieur, pour les séismes suffisammant forts enregistrés dans ces stations durant cette période. Discussion qualitative des courbes obtenues regroupées par azimuts et distances épicentrales proches par rapport à chacune des stations; influence des structures tectoniques traversées

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Wagner, Dörte [Verfasser], e Hans Von [Akademischer Betreuer] Storch. "Evaluation of Storminess by Early 20th Century Atmospheric Data from Signal Stations along the German Coastline / Dörte Wagner ; Betreuer: Hans von Storch". Hamburg : Staats- und Universitätsbibliothek Hamburg, 2017. http://d-nb.info/1147968993/34.

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Sundberg, Simon. "Localization of eNodeBs with a Large Set of Measurements from Train Routers". Thesis, Karlstads universitet, Institutionen för matematik och datavetenskap (from 2013), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-75456.

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This master thesis investigates the possibility of locating LTE base stations, known as eNodeBs, using signal measurements collected by routers on trains. Four existing algorithms for transmitter localization are adopted: the centroid, strongest signal, Monte Carlo path loss simulation and power difference of arrival (PDoA) methods. An improved version of Monte Carlo path loss simulation called logloss fitting is proposed. Furthermore, a novel localization method called sector fitting is presented, which operates solely on the cell identity and geographical distribution of the measurements. The methods are evaluated for a set of manually located eNodeBs, and the results are compared to other external systems that can be used to locate eNodeBs. It is found that the novel sector fitting algorithm is able to considerably improve the accuracy of the logloss fitting and PDoA methods, but weighted centroid is overall the most accurate of the considered methods, providing a median error of approximately 1 km. The Google Geolocation API and Mozilla Location Service still provides estimates that are generally closer to the true location than any of the considered methods. However, for a subset of eNodeBs where measurements from all sectors are available, the novel sector fitting algorithm combined with logloss fitting outperforms the external systems. Therefore, a hybrid approach is suggested, where sector fitting combined with logloss fitting or weighted centroid is used to locate eNodeBs that have measurements from all sectors, while Google Geolocation API or Mozilla Location Service is used to locate the remaining eNodeBs. It is concluded that while the localization performance for those eNodeBs that have measurements from all sectors is relatively good, further improvements to the overall results can likely be obtained in future work by considering environmental factors, the angular losses introduced by directional antennas, and the effects of downlink power control.

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Pelcat, Maxime. "Prototypage Rapide et Génération de Code pour DSP Multi-Coeurs Appliqués à la Couche Physique des Stations de Base 3GPP LTE". Phd thesis, INSA de Rennes, 2010. http://tel.archives-ouvertes.fr/tel-00578043.

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Le standard 3GPP LTE (Long Term Evolution) est un nouveau standard de télécommunication terrestre dont la couche physique des stations de base, appelées eNodeB, est particulièrement coûteuse. Les processeurs de traitement du signal (DSP) sont largement employés dans les stations de base pour calculer les algorithmes de la couche physique. Les DSPs de dernière génération sont des systèmes complexes et hétérogènes. Il n'existe pas actuellement de solution idéale pour distribuer les parties d'une application comme le LTE sur les différents cœurs contenus dans un eNodeB. Dans cette thèse, nous présentons une méthode de travail pour le prototypage rapide et la génération de code automatique. Certains algorithmes de la couche physique du LTE étant trop variables pour une distribution hors-ligne, nous présentons un distributeur adaptatif capable de faire des choix en temps réel sur la base de temps d'exécution prédits.

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Sun, Zhibin. "Application of artificial neural networks in early detection of Mastitis from improved data collected on-line by robotic milking stations". Lincoln University, 2008. http://hdl.handle.net/10182/665.

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Two types of artificial neural networks, Multilayer Perceptron (MLP) and Self-organizing Feature Map (SOM), were employed to detect mastitis for robotic milking stations using the preprocessed data relating to the electrical conductivity and milk yield. The SOM was developed to classify the health status into three categories: healthy, moderately ill and severely ill. The clustering results were successfully evaluated and validated by using statistical techniques such as K-means clustering, ANOVA and Least Significant Difference. The result shows that the SOM could be used in the robotic milking stations as a detection model for mastitis. For developing MLP models, a new mastitis definition based on higher EC and lower quarter yield was created and Principle Components Analysis technique was adopted for addressing the problem of multi-colinearity existed in the data. Four MLPs with four combined datasets were developed and the results manifested that the PCA-based MLP model is superior to other non-PCA-based models in many respects such as less complexity, higher predictive accuracy. The overall correct classification rate (CCR), sensitivity and specificity of the model was 90.74 %, 86.90 and 91.36, respectively. We conclude that the PCA-based model developed here can improve the accuracy of prediction of mastitis by robotic milking stations.

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Più fonti

Libri sul tema "Signal stations"

Vereshchagin A.V., Zatuchny D.A., Sinitsyn V.A., Sinitsyn E.A. e Shatrakov Y.G. Signal Processing of Airborne Radar Stations. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-13-9988-6.

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Smith, Phyllis. Weather pioneers: The Signal Corps station at Pikes Peak. Athens, Ohio: Swallow Press, Ohio University Press, 1993.

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Harrington, Thomas P. Tune the hidden signals on satellite tv: The secret signal on satellite tv. 3^a ed. Columbus, OH: Universal Electronics, Inc., 1992.

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Duffy, Robert A. Boosting the signal: A long year in the lives of four public television stations. Washington, DC: Corporation for Public Broadcasting, 1996.

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Downey, Michael J. Engineer's handbook for earth station design and implementation. 2^a ed. [Thurmont, Md: M/R Communications, 1994.

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Keith, Michael C. Signals in the air: Native broadcasting in America. Westport, Conn: Praeger, 1995.

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W4UYZ e KC4TE, a cura di. Amateur Radio DX blue book: DX operation guide : up-dated world wide amateur radio prefix listings and new reference maps. Cocoa, FL: J/C Enterprises, 1993.

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Nelson, Glenn K. NIST time and frequency radio stations: WWW, WWVH, and WWVB. Boulder, Colo: U.S. Dept. of Commerce, Technology Administration, National Institute of Standards and Technology, Time and Frequncy Division, Physics Laboratory, 2005.

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Adhikari, B. Cropping system monitoring in Off-Station Research Site, Sigana. Pokhara: Lumle Regional Agricultural Research Centre, 1997.

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Association, Seven Seas Cruising, a cura di. S.S.C.A.: Amateur radio callsign book, including nets and worldwide weather reference digest. Fort Lauderdale, Fla. (521 South Andrews Ave., Fort Lauderdale, Fla. 33301-2841): Seven Seas Cruising Association, 1992.

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Capitoli di libri sul tema "Signal stations"

Fedorenko, Yury V., Eystein S. Husebye e Tatiana Matveeva. "A 2-D Seismic Signal Detector for Stand Alone 3-Component stations". In NATO Science Series: IV: Earth and Environmental Sciences, 189–96. Dordrecht: Springer Netherlands, 2008. http://dx.doi.org/10.1007/978-1-4020-6815-7_13.

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Zhang, Chen, Yu-Lai Zheng, Qiang Wang, Yong Li e Zi-Han Li. "Monte Carlo Simulation and Analysis of Specified Element Samples by Nuclear Resonance Fluorescence Detection". In Springer Proceedings in Physics, 985–93. Singapore: Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-99-1023-6_83.

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AbstractThe detection of explosives and drugs in large cargo distribution centers such as customs and logistics stations has a great effect on preventing smuggling crimes and terrorist incidents. However, the relatively thick shielding of container cargo makes the material composition information obtained by conventional detection methods such as X-ray transmission detection and imaging technology very limited. Nuclear Resonance Fluorescence (NRF) is an emerging nondestructive assay technology that uses the specific resonance energy of nuclides to identify unknown nuclides, which can be used to detect and analyze the isotopic composition of the inspected cargo. In this paper, according to the theoretical analysis of NRF, Geant4 is used to build the NRF backscatter detection model, the collimator structure of the electron accelerator and the background shield of the NRF signal are optimized and calculated, and the NRF process with 12C as the target element is simulated and calculated. The results show that the simulated characteristic energy spectrum of NRF signal is consistent with the theory, the designed background shielding scheme meets the needs of NRF signal identification and detection, and the simulated signal-to-noise ratio data provides the basis for the experiment.

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Wang, Xin, Qilian Liang, Baoju Zhang e Xiaorong Wu. "Joint Power and Spectrum Allocation for Relay Stations in Mobile Relay Networks". In The Proceedings of the Second International Conference on Communications, Signal Processing, and Systems, 831–38. Cham: Springer International Publishing, 2013. http://dx.doi.org/10.1007/978-3-319-00536-2_95.

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Lebrun, Stéphanie, Stéphane Kaloustian, Raphaël Rollier e Colin Barschel. "GNSS Positioning Security: Automatic Anomaly Detection on Reference Stations". In Critical Information Infrastructures Security, 60–76. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-93200-8_4.

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AbstractThe dependency of critical infrastructures on Global Navigation Satellite Systems (GNSS) keeps increasing over the years. This over-reliance brings concerns as those systems are vulnerable and consequently prone to human-made perturbations, such as jamming and spoofing attacks. Solutions for detecting such disturbances are therefore crucially needed to raise GNSS users’ awareness and protection. This paper suggests an approach for detecting anomalous events (i.e., potentially an attack attempt) based on measurements recorded by Continuously Operating GNSS Reference Stations (CORS). Precisely, the anomaly detection process first consists in modeling the normal behavior of a given signal thanks to a predictive model which combines the Seasonal and Trend decomposition using LOESS and ARIMA algorithms. This model can then be used to predict the upcoming measurement values. Finally, we compare the predictions to the actual observations with a statistical rule and assess if those are normal or anomalous. While our anomaly detection approach is intended for real-time use, we assess its effectiveness on historical data. For simplicity and independence, we also focus on the Carrier-to-Noise Ratio only, though similar methods could apply to other observables. Our results prove the sensitivity of the proposed detection on a reported case of unintentional disturbance. Other anomalies in the historical data are also uncovered using that methodology and presented in this paper.

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Xie, Chao, Deyong Xian, Teng Li, Guotai Wang e Qian Wang. "Analysis of GPS Signal Power Enhancement Effect Based on Data from Multiple Ground Stations". In Lecture Notes in Electrical Engineering, 3–10. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-16-3142-9_1.

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Fei, Zhou, e Fan Xin-Yue. "Improved Positioning Algorithm Using the Linear Constraints of Scatterer in Two Base Stations". In The Proceedings of the Second International Conference on Communications, Signal Processing, and Systems, 945–52. Cham: Springer International Publishing, 2013. http://dx.doi.org/10.1007/978-3-319-00536-2_109.

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Gitterman, Yefim, Vladimir Pinsky e Rami Hofstetter. "Signal Processing for Indian and Pakistan Nuclear Tests Recorded at IMS Stations Located in Israel". In Monitoring the Comprehensive Nuclear-Test-Ban Treaty: Seismic Event Discrimination and Identification, 779–801. Basel: Birkhäuser Basel, 2002. http://dx.doi.org/10.1007/978-3-0348-8169-2_10.

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Shen, Yunzhong, e Weiwei Li. "Spatiotemporal Signal and Noise Analysis of GPS Position Time Series of the Permanent Stations in China". In International Association of Geodesy Symposia, 231–37. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-37222-3_30.

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Unwin, Philip. "Stations and Signals". In Travelling by Train in the Edwardian Age, 79–92. London: Routledge, 2023. http://dx.doi.org/10.4324/9781003457107-5.

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Balakrishna, K., e N. G. Sandesh. "Design of Dynamic Induction Charging Vehicle for Glimpse of Future: Cutting Down the Need for High-Capacity Batteries and Charging Stations". In Advances in VLSI, Signal Processing, Power Electronics, IoT, Communication and Embedded Systems, 197–204. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-16-0443-0_16.

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Atti di convegni sul tema "Signal stations"

Vosoughi, Aida, Michael Wu e Joseph R. Cavallaro. "Baseband signal compression in wireless base stations". In GLOBECOM 2012 - 2012 IEEE Global Communications Conference. IEEE, 2012. http://dx.doi.org/10.1109/glocom.2012.6503828.

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Song, Ning, Yan Zhou, Dongjie Tan, Yunbin Ma, Honghui Qiu e Baisong Li. "Research on Fiber Perimeter Security Technique of Station". In 2012 9th International Pipeline Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/ipc2012-90074.

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The oil or gas station is an important producing unit, building a perimeter security system is an available method for protecting the stations and improving the capacity of dealing with the emergency incident. However, building high walls or fence and patrolling the stations are the main protecting methods, it is difficult to detect invasion immediately. So, it is necessary to construct a stable and reliable perimeter security system to protect the station. Traditional fiber perimeter security technology protects the station by sensing fiber on the fence or wall, but the wind will produce many false alarms. In this paper, a multi-mode sensing cable buried in the ground, systems can not only effectively detect intrusions, but more importantly, avoid false alarms by wind disturbance. Intrusions will produce non-stationary random signals, through the signal processing and recognizing technique, we can identify the invasion and improve the accuracy and stability of the system.

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Menon, Abhishek R., e Amritha Aravind. "Offline Train Tracking System". In 2nd International Conference on Modern Trends in Engineering Technology and Management. AIJR Publisher, 2023. http://dx.doi.org/10.21467/proceedings.160.19.

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Population growth is directly related to transportation connectivity. In India, transport facilities are primarily served by Indian Railways. The work “OFFLINE TRAIN TRACKING SYSTEM” works on transmitter receiver-based logic. Transmitters are installed at stations and receivers are installed inside trains. When the train comes within range of the transmitter, the receiver receives the signal and displays the station name on the LCD screen. Transmitters installed at stations operate on 230 V AC and receivers in trains operate on 9 V DC. Work is not manually controlled. If the transmitter is on and the receiver is receiving the signal. Then, the station name is automatically displayed on the display. The work is not manually controlled. When the transmitter is ON and the receiver receives signals from transmitter, then the display unit automatically displays the station name. NRF Transceiver is used in both railway station and train. Lora transceiver can also be used in place of NRF transceiver module, it has the range of 2.5 Km, and it can be more helpful in the case of early projection of forthcoming station. NRF transceiver has the range of 500 meters. It is not expensive and effective in nature. Lora transceiver is expensive and more effective than NRF module. Microcontroller is used in this project, and it is programmed with Embedded C. LCD Display and voice alert is installed with the microcontroller. As the transceiver in the station gives area information to the transceiver located in the train, the microcontroller projects the station name in the display and voice alert is also installed.

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Bugaj, Marek, e Rafał Przesmycki. "The measurement of baseband frequency range for military satellite terminals". In 8th International Conference on Human Interaction and Emerging Technologies. AHFE International, 2022. http://dx.doi.org/10.54941/ahfe1002740.

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VSAT stations (Very Small Aperture Terminals) are small, cheap terrestrial satellite stations, which are equipped with small antennas (typically from 1 m to 2 m), low power RF transmitters (typically from 0.5 W to 2 W) and in modems and signal converters, forming a compact structure. Stations can be very easily installed on the roof, wall or car park in front of the user's office, where the end devices are placed. Stations can be used in a very convenient and economical way to connect end users devices to the main computer located in a remote data center. VSAT stations are usually used to transmit digital data.VSAT stations often work in a star network. VSAT stations communicate with a large ground station, called the central station. In this case, the type of modulation, transmission rate, coding and access methods for the outgoing channel (from the central station to the VSAT station) and for the incoming channel (from the VSAT station to the central station) are usually differentiated, in order to use the satellite channel effectively, using methods multiplied access. In this type of VSAT networks, user data is usually processed by VSAT stations and the central station, so as to effectively support various computer network protocols.The article concerns problems related to electromagnetic compatibility of military satellite terminal with small VSAT antennas (Very Small Aperture Terminals). The article focuses on the measurement of the frequency range of military satellite terminal work in the basic band for VSAT satellite terminals intended for data transmission. The article presents a laboratory stand and a method for measuring the operating frequency in the basic band for VSAT satellite terminals, which was developed on the basis of European civil standards and a military standard containing requirements on the operating frequency in the basic band for VSAT. In the case of measuring the operating frequency in the basic band for satellite terminals of the tested device, we must remember to estimate the uncertainty of the measurement. The extended value of the uncertainty of measurement for individual frequency ranges is determined from the f0± 2*10^-7 relationship.

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Li, Bo, e Hong Tang. "Research on Throughput Maximization of Wireless Powered Communication Network based on a Retro Directive Matrix". In 8th International Conference on Natural Language Processing (NATP 2022). Academy and Industry Research Collaboration Center (AIRCC), 2022. http://dx.doi.org/10.5121/csit.2022.120104.

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Aiming at the problem of limited system throughput caused by double near-far effect in wireless power communication network. In this paper, a retro directive matrix method based on phase conjugation is proposed. In the method, energy base stations and information base stations are depolyed separately, energy base station uses large-scale multiple input multiple output (MIMO) system, when system running point equipment firstly to send a beacon signal to energy base station, the energy base station amplifies its conjugate to form a directional beam to achieve multi-input and multi-output energy gains, thus improving the throughput of information transmission of node devices. Through the optimizated and allocated the time of beacon signal, the time of energy transmission, the time of information transmission and some power parameters, a convex optimization problem is proposed. And it has been solved by Lagrange generalized multiplier method and golden section method. Simulation results show that the proposed method has better performance than others projects.

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Li, Jiamin, Dongming Wang, Pengcheng Zhu, Xiaohu You e Lan Tang. "An improved distributed iterative beamforming algorithm with cooperative base stations". In Signal Processing (WCSP 2011). IEEE, 2011. http://dx.doi.org/10.1109/wcsp.2011.6096696.

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Lin, Min, Jian Ouyang e Yingtao Niu. "A simple downlink diversity transmit scheme for cooperative base stations". In Signal Processing (WCSP 2011). IEEE, 2011. http://dx.doi.org/10.1109/wcsp.2011.6096864.

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Jeon, Sangbong, Ae-kyoung Lee, Jungsun Um e Hyung-Do Choi. "Estimation of EMF for base stations using signal decoding technique". In 2019 URSI Asia-Pacific Radio Science Conference (AP-RASC). IEEE, 2019. http://dx.doi.org/10.23919/ursiap-rasc.2019.8738326.

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Cebrian, Joan Manuel, Joan Picanyol, Laura Gonzalez, Cristina Lavin, Oscar Gago, Francisco Amarillo, Gonzalo Seco-Granados et al. "ADIBEAM: Design and experimental validation of a robust beamforming platform for Galileo reference ground stations". In European Workshop on GNSS Signals and Signal Processing. IEEE, 2010. http://dx.doi.org/10.1109/navitec.2010.5707996.

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Zhao, Botao, e Fan Yang. "Compatibility evaluation and technical analysis of C-band broadcasting satellite receiving stations against 5G base station". In Second International Conference on Digital Signal and Computer Communications (DSCC 2022), a cura di Sandeep Saxena. SPIE, 2022. http://dx.doi.org/10.1117/12.2641336.

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Rapporti di organizzazioni sul tema "Signal stations"

Farahbod, A. M., e J. F. Cassidy. An overview of seismic attenuation in the Eastern Canadian Arctic and the Hudson Bay Complex, Manitoba, Newfoundland and Labrador, Nunavut, Ontario, and Quebec. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/330396.

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In this study we investigated coda-wave attenuation (QC) from the eastern Canadian Arctic in Nunavut and the Hudson Bay complex including portions of northern Manitoba, Ontario, Quebec and Labrador. We used earthquake recordings from 15 broadband and 3 short period seismograph stations of the Canadian National Seismic Network (CNSN) and 29 broadband stations of the POLARIS network across the region. Our dataset is comprised of 637 earthquakes recorded between 1985 and 2021 with magnitudes ranging from 1.3 to 6.1, depths from 0 to 20 km and epicentral distances of 5 to 100 km. This gives a total of 246 high signal-to-noise (S/N) traces (S/N[lesser/equal]5.0) useful for QC calculation (with a maximum ellipse parameter, a2, of 100) across the region. Coda windows were selected to start at tc = 2tS (two times the travel time of the direct S wave), and were filtered at center frequencies of 2, 4, 8, 12 and 16 Hz. Our study reveals a consistent pattern. We find that in the northern section of the study area, the highest Q0 values (e.g., Q0 of 110 and 112) are at station POIN and station RES, respectively, which are located in the older Archean province. The lowest Q0 values that we find (e.g., Q0 of 55 and 61) are at station AKVQ and IVKQ respectively, located in northern Quebec. Smaller Q0 values for stations in the south are explained by the younger age of the rocks and proximity to the main fault systems. An average for all the data results in a Q relationship of QC = 82f1.08 for the frequency band of 2 to 16 Hz for the entire region.

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Farahbod, A. M., e J. F. Cassidy. An overview of seismic attenuation in the Charlevoix Seismic Zone, southern Quebec. Natural Resources Canada/CMSS/Information Management, 2023. http://dx.doi.org/10.4095/332158.

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We investigate seismic attenuation characteristics of the Charlevoix Seismic Zone. This zone is located ~100 km downstream from Quebec City and is the most seismically active region of eastern Canada. We used earthquake recordings from 8 seismograph stations of the Canadian National Seismic Network (CNSN) across the region. Our dataset is comprised of 584 earthquakes recorded between 1992 and 2022 with magnitudes ranging from 2.0 to 5.4, depths from 0 to 30 km and epicentral distances of 5 to 100 km. This gives a total of 1490 high signal-to-noise (S/N) traces (S/N?5.0) useful for QC calculation (with a maximum ellipse parameter, a2, of 100) across the region. Coda windows were selected to start at tc = 2tS (two times the travel time of the direct S wave), and were filtered at center frequencies of 2, 4, 8, 12 and 16 Hz. Our study reveals a consistent pattern. We find that the highest Q0 (Q at 1 Hz) values are at station A11 (e.g., Q0 of 109), that is the farthest station from the 1663, M~7 earthquake (D=40 km), excluding the new station of CACQ. The lowest Q0 values that we find are at the station A16 (e.g., Q0 of 72) that is the second closest station to the epicenter of the 1663 earthquake (D=16 km) after station A61 (D=10 km). Also, we find the lowest overall average Q0 values at station A16 (e.g., Q0 of 72). In general, Q0 is lower in the vicinity of large earthquakes (Jin & Aki, 1988). Therefore, the low Q0 values at station A16 may suggest that the 1663 earthquake is located slightly southeast of the catalog epicenter, considering high uncertainty associated with historic events. An average for all the data results in a Q relationship of QC = 81f1.06 for the frequency band of 2 to 16 Hz for the entire region.

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DeRobertis, Michelle, Christopher E. Ferrell, Richard W. Lee e David Moore. City Best Practices to Improve Transit Operations and Safety. Mineta Transportation Institute, aprile 2021. http://dx.doi.org/10.31979/mti.2021.1951.

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Public, fixed-route transit services most commonly operate on public streets. In addition, transit passengers must use sidewalks to access transit stops and stations. However, streets and sidewalks are under the jurisdiction of municipalities, not transit agencies. Various municipal policies, practices, and decisions affect transit operations, rider convenience, and passenger safety. Thus, these government entities have an important influence over the quality, safety, and convenience of transit services in their jurisdictions. This research identified municipal policies and practices that affect public transport providers’ ability to deliver transit services. They were found from a comprehensive literature review, interviews and discussions with five local transit agencies in the U.S., five public transportation experts and staff from five California cities. The city policies and practices identified fall into the following five categories: Infrastructure for buses, including bus lanes, signal treatments, curbside access; Infrastructure for pedestrians walking and bicycling to, and waiting at, transit stops and stations; Internal transportation planning policies and practices; Land development review policies; Regional and metropolitan planning organization (MPO) issues. The understanding, acknowledgment, and implementation of policies and practices identified in this report can help municipalities proactively work with local transit providers to more efficiently and effectively operate transit service and improve passenger comfort and safety on city streets.

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Farahbod, A., e J. F. Cassidy. Spatial and temporal variations in seismic coda Q attenuation in the lower St. Lawrence region, southeastern Quebec. Natural Resources Canada/CMSS/Information Management, 2023. http://dx.doi.org/10.4095/332027.

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We investigate seismic attenuation characteristics of the Lower St. Lawrence seismic zone in southeastern Quebec. This zone is located ~400 km downstream from Quebec City and is between the Quebec North Shore and the Lower St. Lawrence. We used earthquake recordings from 5 broadband and 5 short period seismograph stations of the Canadian National Seismic Network (CNSN) across the region. Our dataset is comprised of 847 earthquakes recorded between 1985 and 2022 with magnitudes ranging from 2.0 to 5.1, depths from 0 to 30 km and epicentral distances of 5 to 100 km. This gives a total of 446 high signal-to-noise (S/N) traces (S/N?5.0) useful for QC calculation (with a maximum ellipse parameter, a2, of 100) across the region. Coda windows were selected to start at tc = 2tS (two times the travel time of the direct S wave), and were filtered at center frequencies of 2, 4, 8, 12 and 16 Hz. Our study reveals a consistent pattern. We find that the lowest overall average of Q0 (Q at 1 Hz) values are at the three stations (GSQ, ICQ and SMQ) within 100 km of a moderate earthquake of mN 5.1 in 1999 (e.g., Q0 of 81, 88 and 80, respectively). We determined temporal variations in attenuation following the 1999 earthquake. The overall average of Q0 decreased from 87 (before the mainshock) to 77 (GSQ, D=96 km), from 92 to 85 (ICQ, D=69 km) and from 88 to 82 (SMQ, D=73 km). These results are in agreement with global studies that show a decrease in Q0 following a significant earthquake, (e.g., M &gt; 5) likely the result of increased fracturing and fluids in the epicentral region. An average for all the data results in a Q relationship of QC = 86f1.07 for the frequency band of 2 to 16 Hz for the entire region.

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Weissinger, Rebecca. Trends in water quality at Bryce Canyon National Park, water years 2006–2021. A cura di Alice Wondrak Biel. National Park Service, novembre 2022. http://dx.doi.org/10.36967/2294946.

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The National Park Service collects water-quality samples on a rotating basis at three fixed water-quality stations in Bryce Canyon National Park (NP): Sheep Creek, Yellow Creek, and Mossy Cave Spring. Data collection began at Sheep Creek and Yellow Creek in November 2005 and at Mossy Cave in July 2008. Data on in-situ parameters, fecal-coliform samples, major ions, and nutrients are collected monthly, while trace elements are sampled quarterly. This report analyzes data from the beginning of the period of record for each station through water year 2021 to test for trends over time. Concentrations are also compared to relevant water-quality standards for the State of Utah. Overall, water quality at the park’s monitoring stations continues to be excellent, and park managers have been successful in their goal of maintaining these systems in unimpaired condition. Infrequent but continued Escherichia coli exceedances from trespass livestock at Sheep and Yellow creeks support the need for regular fence maintenance along the park boundary. High-quality conditions may qualify all three sites as Category 1 waters, the highest level of anti-degradation protection provided by the State of Utah. Minimum and maximum air temperatures at the park have increased, while precipitation remains highly variable. Increasing air temperatures have led to increasing water temperatures in Sheep and Yellow creeks. Sheep Creek also had a decrease in flow across several quantiles from 2006 to 2021, while higher flows decreased at Yellow Creek in the same period. Surface flows in these two creeks are likely to be increasingly affected by higher evapotranspiration due to warming air temperatures and possibly decreasing snowmelt runoff as the climate changes. The influx of ancient groundwater in both creek drainages helps sustain base flows at the sites. Mossy Cave Spring, which is sampled close to the spring emergence point, showed less of a climate signal than Sheep and Yellow creeks. In our record, the spring shows a modest increase in discharge, including higher flows at higher air temperatures. An uptick in visitation to Water Canyon and the Mossy Cave Trail has so far not been reflected by changes in water quality. There are additional statistical trends in water-quality parameters at all three sites. However, most of these trends are quite small and are likely ecologically negligible. Some statistical trends may be the result of instrument changes and improvements in quality assurance and quality control over time in both the field sampling effort and the laboratory analyses. Long-term monitoring of water-quality stations at Bryce Canyon NP suggests relatively stable aquatic systems that benefit from protection within the park. To maintain these unimpaired conditions into the future, park managers could consider: Regular fence checks and maintenance along active grazing allotments at the park boundary to protect riparian areas and aquatic systems from trespass livestock. Developing a springs-monitoring program to track changes in springflow at spring emergences to better understand bedrock-aquifer water supplies. These data would also help quantify springflow for use in water-rights hearings. Supporting hydrogeologic investigations to map the extent and flow paths of groundwater aquifers. Working with the State of Utah to develop groundwater-protection zones to protect groundwater aquifers from developments that would affect springs in the park. Prioritizing watershed management with proactive fire risk-reduction practices. Explicitly including watershed protection as a goal in plans for fire management and suppression. Using additional data and analyses to better understand the drivers of trends in water quality and their ecological significance. These could include higher-frequency data to better understand relationships between groundwater, precipitation, and surface flows at the sites. These could also include watershed metrics...

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Farahbod, A. M., e J. F. Cassidy. An overview of seismic attenuation in the Northern Appalachians Seismic Zone, New Brunswick and Nova Scotia. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/329702.

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In this study we investigated coda-wave attenuation (QC) from the northern Appalachian region of eastern Canada in the two provinces of New Brunswick and Nova Scotia. We used earthquake recordings from 8 broadband and 2 short period seismograph stations of the Canadian National Seismograph Network (CNSN) across the region. Our dataset is comprised of 476 earthquakes recorded between 1983 and 2021 with magnitudes ranging from 1.5 to 4.1, depths from 0 to 20 km (with the vast majority being &lt;10 km) and epicentral distances of 5 to 100 km. This gives a total of 261 high signalto- noise (S/N) traces (S/N greater than or equal to 5.0) useful for QC calculation (with a maximum ellipse parameter, a2, of 100) across the region. Coda windows were selected to start at tc = 2tS (two times the travel time of the direct S wave), and were filtered at center frequencies of 2, 4, 8, 12 and 16 Hz. Our study reveals a consistent pattern. We find that in the northern New Brunswick, the lowest Q0 values (e.g., Q0 of 61) are at station KLN which is the closest station to the epicenter of the 1982 Miramichi earthquake (M 5.8). The highest Q0 values that we find (e.g., Q0 of 178) are at station GGN, located in the southern New Brunswick. Smaller Q0 values for stations in the north (closer to the Charlevoix-Kamouraska seismic zone or Miramichi source area) is explained by Jin and Aki's (1988) finding that Q0 is lower in the vicinity of large earthquakes. An average for all the data results in a Q relationship of QC = 99f0.96 for the frequency band of 2 to 16 Hz for the entire region.

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Grimley, Hart e Viana. PR-015-07604-R01 Clamp-On Ultrasonic Flow Meters as Diagnostic Tools. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), giugno 2008. http://dx.doi.org/10.55274/r0011006.

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Over the past several years, improvements in clamp-on ultrasonic meter technology have caused increased interest in applying this technology within the natural gas industry. Clamp-on ultrasonic meters (CUSMs), which are mounted on the outside of a pipe, send and receive ultrasonic waveforms through the pipe wall. This configuration offers several potential advantages over in-line meters, including portability and the ability to be installed without shutdown and disassembly of the pipeline. CUSMs, like their in-line counterparts, use sophisticated electronics to control the meter operation and to monitor parameters such as transducer signal strength, path velocities, and speed of sound. Because of these features, CUSMs are being considered for their potential as in-situ verification and as diagnostic tools. Having such portable tools to quickly verify meter performance would save considerable time in troubleshooting causes of lost and unaccounted-for (LAUF) gas, thus, minimizing overall LAUF totals. The ability to validate meter performance in-situ would also significantly reduce operating and maintenance costs of metering stations, particularly costs of unnecessary recalibrations. This project specifically addressed the ability of a CUSM to measure distorted profiles with sufficient resolution to determine if the flow is properly conditioned for flow measurement by other meter types. It also addressed the accuracy with which CUSM measurements, performed with sufficient spatial fidelity, can be used to provide a reference flow rate for in-situ meter proving. The test approach was to traverse a single ultrasonic transducer pair around the perimeter of the pipe in sufficiently small increments to measure the flow field at a given pipe cross section independent of the amount of flow distortion present. Velocity profile measurements performed at the same locations were used as an independent check of the CUSMs profile sensitivity.

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Videa, Aldo, e Yiyi Wang. Inference of Transit Passenger Counts and Waiting Time Using Wi-Fi Signals. Western Transportation Institute, agosto 2021. http://dx.doi.org/10.15788/1715288737.

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Passenger data such as real-time origin-destination (OD) flows and waiting times are central to planning public transportation services and improving visitor experience. This project explored the use of Internet of Things (IoT) Technology to infer transit ridership and waiting time at bus stops. Specifically, this study explored the use of Raspberry Pi computers, which are small and inexpensive sets of hardware, to scan the Wi-Fi networks of passengers’ smartphones. The process was used to infer passenger counts and obtain information on passenger trajectories based on Global Positioning System (GPS) data. The research was conducted as a case study of the Streamline Bus System in Bozeman, Montana. To evaluate the reliability of the data collected with the Raspberry Pi computers, the study conducted technology-based estimation of ridership, OD flows, wait time, and travel time for a comparison with ground truth data (passenger surveys, manual data counts, and bus travel times). This study introduced the use of a wireless Wi-Fi scanning device for transit data collection, called a Smart Station. It combines an innovative set of hardware and software to create a non-intrusive and passive data collection mechanism. Through the field testing and comparison evaluation with ground truth data, the Smart Station produced accurate estimates of ridership, origin-destination characteristics, wait times, and travel times. Ridership data has traditionally been collected through a combination of manual surveys and Automatic Passenger Counter (APC) systems, which can be time-consuming and expensive, with limited capabilities to produce real-time data. The Smart Station shows promise as an accurate and cost-effective alternative. The advantages of using Smart Station over traditional data collection methods include the following: (1) Wireless, automated data collection and retrieval, (2) Real-time observation of passenger behavior, (3) Negligible maintenance after programming and installing the hardware, (4) Low costs of hardware, software, and installation, and (5) Simple and short programming and installation time. If further validated through additional research and development, the device could help transit systems facilitate data collection for route optimization, trip planning tools, and traveler information systems.

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Becker, Alex, e William Frangos. Magnetic fields of AM band radio broadcast signals at theRichmond Fiel d Station. Office of Scientific and Technical Information (OSTI), dicembre 1998. http://dx.doi.org/10.2172/7363.

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Chiel, Elad, e Christopher J. Geden. Development of sustainable fly management tools in an era of global warming. United States Department of Agriculture, gennaio 2014. http://dx.doi.org/10.32747/2014.7598161.bard.

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House flies (Muscadomestica) are global pests of animal agriculture, causing major annoyance, carrying pathogens among production facilities and humans and thus have profound impacts on animal comfort and productivity. Successful fly control requires an integrated pest management (IPM) approach that includes elements of manure management, mass trapping, biological control, and selective insecticide use. Insecticidal control of house flies has become increasingly difficult due to the rapidity with which resistance develops, even to new active ingredients. Global climate change poses additional challenges, as the efficacy of natural enemies is uncertain under the higher temperatures that are predicted to become more commonplace in the future. The two major objectives of this research project were: 1) to develop a cost-effective autodissemination application method of Pyriproxifen (PPF), an insect growth regulator, for controlling house flies; 2) to study the effect of increasing temperatures on the interactions between house flies and their principal natural enemies. First, we collected several wild house fly populations in both countries and established that most of them are susceptible to PPF, although one population in each country showed initial signs of PPF-resistance. An important finding is that the efficacy of PPF is substantially reduced when applied in cows’ manure. We also found that PPF is compatible with several common species of parasitoids that attack the house fly, thus PPF can be used in IPM programs. Next, we tried to develop “baited stations” in which house flies will collect PPF on their bodies and then deliver and deposit it in their oviposition sites (= autodissemination). The concept showed potential in lab experiments and in outdoor cages trials, but under field conditions the station models we tested were not effective enough. We thus tested a somewhat different approach – to actively release a small proportion of PPF-treated flies. This approach showed positive results in laboratory experiments and awaits further field experiments. On the second topic, we performed two experimental sets: 1) we collected house flies and their parasitoids from hot temperature and mild temperature areas in both countries and, by measuring some fitness parameters we tested whether the ones collected from hot areas are better adapted to BARD Report - Project 4701 Page 2 of 16 heat. The results showed very little differences between the populations, both of flies and parasitoids. 2) A “fast evolution” experiment, in which we reared house flies for 20 generations under increasing temperatures. Also here, we found no evidence for heat adaptation. In summary, pyriproxyfen proved to be a highly effective insect growth regulator for house flies that is compatible with it’s natural enemies. Although our autodissemination stations yielded disappointing results, we documented the proportion of flies in a population that must be exposed to PPF to achieve effective fly control. Both the flies and their principal parasitoids show no evidence for local adaptation to high temperatures. This is an encouraging finding for biological control, as our hypothesis was that the fly would be adapting faster to high temperatures than the parasitoids. BARD Report - Project 4701 Page 3 of 16

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