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Journal articles on the topic 'Ionograma'

Author: Grafiati

Published: 4 June 2021

Last updated: 2 February 2022

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1

Costa, Margarete, and Nivaldo Marins. "Hiponatremia associada a antidepressivos: uma revisão." Jornal Brasileiro de Psiquiatria 67, no. 1 (March 2018): 52–58. http://dx.doi.org/10.1590/0047-2085000000184.

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RESUMO Objetivo Rever a literatura mais recente sobre a associação entre a hiponatremia e o uso de antidepressivos. Métodos Pesquisa bibliográfica nas bases de dados PubMed e SciELO, com os descritores “antidepressive agents” e “hyponatremia”, incluindo artigos de janeiro de 2006 a maio de 2016. Resultados Foram incluídos 45 artigos. A idade, o sexo feminino e a polimedicação são os fatores de risco mais relevantes, e os sintomas dependem da gravidade da hiponatremia. A hiponatremia pode ter várias causas, sendo a mais comum a síndrome da secreção inapropriada do hormônio antidiurético. Entre os inibidores seletivos da recaptação de serotonina, o citalopram e o escitalopram apresentam risco superior, à semelhança da venlafaxina. O risco de hiponatremia parece ser inferior com as classes restantes, à exceção dos inibidores da monoaminoxidase. Recomenda-se um ionograma prévio ao tratamento em doentes com mais de 60 anos e, sempre, um ionograma um mês após o seu início. O primeiro passo do tratamento é a suspensão do fármaco, revertendo a maioria dos casos leves. No entanto, o tratamento deve ser individualizado, considerando os riscos da hiponatremia e da correção. Conclusões A hiponatremia é um efeito colateral a considerar nos doentes que tomam antidepressivos. Quando a manutenção do tratamento é necessária, deve ser evitado o mesmo antidepressivo ou outro da mesma classe, sendo opções a trazodona, abupropiona, a agomelatina, a mirtazapina e a reboxetina, porque existem poucos relatos de hiponatremia com esses fármacos.

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2

Mochalov, Vladimir, and Anastasia Mochalova. "Extraction of ionosphere parameters in ionograms using deep learning." E3S Web of Conferences 127 (2019): 01004. http://dx.doi.org/10.1051/e3sconf/201912701004.

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Based on a new developed author’s method for recognition traces of reflections from different layers of the ionosphere in ionograms, the ionosphere parameters are extracted. The method is based on the use of deep neural networks (DNN). The rules for extracting the ionosphere parameters in ionograms are given. Based on the results obtained by the authors, an intelligent support system for ionogram analysis is being developed.

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3

Ларюнин, Олег, Oleg Laryunin, Алексей Подлесный, Aleksey Podlesnyi, Олег Романовский, and Oleg Romanovskii. "Interpretation of oblique-incidence ionograms under the assumption of a spherically stratified ionosphere." Solnechno-Zemnaya Fizika 1, no. 4 (December 17, 2015): 66–71. http://dx.doi.org/10.12737/13388.

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Oblique sounding ionograms show that an ionogram trace can be of nose shape with typical multipath for which the maximum corresponds to maximum usable frequency. However, ionograms obtained from sounding at short paths are of classical type and do not differ from vertical sounding ionograms in appearance. On the basis of ray tracing in isotropic medium we examined changes in ionogram structure when varying the ground range. It is shown that in a stratified medium, multipath can take place at any nonzero ground range though at short paths, to resolve multipathing in an experiment seems to be impossible. Some possibilities for using the assumption of sphe-rically stratified ionosphere when sounding at long radio paths (of the order of few thousand kilometers) are also under consideration. We compared the distance-frequency characteristics (DFC) produced for horizontally-nonuniform ionosphere defined along the path by IRI-2012 model, as well as for spherical-stratified ionosphere for which the height profile does not depend on horizontal coordinate and agrees with IRI-2012 profile in the middle point of the path. Although the electron density profiles exhibit significant variations along the path, DFCs agree with each other up to fraction of the percent. In this case, the form of the ionogram practically in everything is defined by the vicinity of radio path middle point.

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Faretta, Daniela, Felisa Vilches, Julieta Michelli, Yanina Soledad Oliva, María Clara Fritz, Silvina Del Luca, María De Luján Calcagno, et al. "P46 Cambios del metabolismo mineral óseo luego de la cirugía bariátrica en pacientes con diabetes mellitus tipo 2 y obesidad." Revista de la Sociedad Argentina de Diabetes 54, no. 3Sup (November 21, 2020): 151. http://dx.doi.org/10.47196/diab.v54i3sup.432.

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Introducción: la cirugía bariátrica (CB) es un tratamiento altamente efectivo para los pacientes con diabetes mellitus tipo 2 y obesidad, pero tiene efectos negativos sobre el metabolismo óseo.Objetivos: evaluar los cambios del metabolismo fosfocálcico luego de la CB en una población de pacientes con diabetes y obesidad.Materiales y métodos: 56 pacientes con diabetes fueron estudiados pre y post cirugía bariátrica (CB); se recabaron datos personales, medidas antropométricas. Se calculó índice de masa corporal (IMC). Se midieron albúmina, calcio, fósforo, creatinina, ionograma, magnesio en sangre y orina de 24 h y vitamina D. Análisis estadístico se realizó Test de Student o Test de Mann-Whitney y/o Test de Wilcoxon. Se calculó el coeficiente de correlación de Spearman. Valores expresados en media ± desvío estándar. p significativa p˂0,05.

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5

Zhao, J. J., C. Zhou, G. B. Yang, C. H. Jiang, S. S. Chang, P. Zhu, X. D. Gu, B. B. Ni, and Z. Y. Zhao. "A new inversion algorithm for backscatter ionogram and its experimental validation." Annales Geophysicae 32, no. 4 (April 28, 2014): 465–72. http://dx.doi.org/10.5194/angeo-32-465-2014.

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Abstract. Oblique backscatter sounding is a powerful tool for detecting and monitoring the ionosphere continuously at a remote distance. High-frequency (HF) backscatter ionograms provide the amplitudes of backscatter signals with respect to group path or time delay against operating frequency. Application of inversion algorithm to a backscatter ionogram can extract useful information regarding the ionospheric electron density along the propagation paths. The present study proposes a new inversion algorithm on basis of simulated annealing method to acquire the leading edge of sweep-frequency ionogram, which is subsequently validated by ionospheric vertical sounding data. Quantitative comparisons between the vertical sounding measurements and the inversion results obtained from oblique backscatter sounding indicate that the new algorithm enables us to overcome the instability issue that traditional inversion algorithm faces and output reliable information of ionospheric inversion with satisfactory efficiency, thus providing a robust alternative for ionospheric detection based on oblique backscatter ionograms especially when the ionosphere is calm with slow changes.

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6

Marín del Barrio, S., P. González Carretero, R. Garrido Romero, K. M. Juma Azara, and C. Luaces Cubells. "Utilidad del equilibrio ácido-base y del ionograma en el tratamiento de la gastroenteritis aguda." Anales de Pediatría 69, no. 4 (October 2008): 322–28. http://dx.doi.org/10.1157/13126556.

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7

Ribeiro, E. E. A., M. C. S. Batista, M. A. M. Carvalho, and J. A. L. Silva. "Níveis iônicos e enzimáticos de cutias (Dasyprocta sp.) hígidas, criadas em cativeiro, influência do sexo e da idade." Arquivo Brasileiro de Medicina Veterinária e Zootecnia 60, no. 3 (June 2008): 651–55. http://dx.doi.org/10.1590/s0102-09352008000300019.

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Determinou-se o perfil do ionograma e enzimas hepáticas de cutias (Dasyprocta sp.) saudáveis, criadas em cativeiro, como também se avaliou a influência de sexo, idade e interação sexo-idade. Foi adotado um delineamento inteiramente ao acaso, em arranjo fatorial 2 x 4 (dois sexos e quatro faixas etárias), com três repetições, totalizando 24 cutias. Foram determinados os valores para o cálcio (Ca), fósforo (P), cloretos (Cl), aspartato aminotransferase (AST), alanina aminotransferase (ALT), fosfatase alcalina (FA) e gama-glutamiltransferase (GGT). Os valores médios obtidos foram: Ca= 7,62+2,59mg/dl; P= 3,91+1,41mg/dl; Cl= 58,63+16,45mg/dl; AST= 119,54+79,35UI/ml; ALT= 28,08+15,53UI/ml; FA= 26,95+14,01UI/ml e GGT= 25,34+19,44UI/ml. O valor de P foi maior nas fêmeas e da FA nos machos. Os níveis de FA diminuíram com o aumento da idade.

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8

Ларюнин, Олег, and Oleg Laryunin. "Numerical synthesis of ionograms in horizontally inhomogeneous ionosphere on the basis of compound parabolic layer model." Solar-Terrestrial Physics 2, no. 3 (October 27, 2016): 74–86. http://dx.doi.org/10.12737/22286.

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Characteristic U-shaped traces (cusps) on ionograms have been identified as off-angle echoes from sloping electron density contours caused by the presence of traveling ionospheric disturbances (TIDs). Temporal evolution of the cusps is associated with horizontal drift of the disturbances. A potential for reducing calculation time in numerical synthesis of vertical ionograms is under discussion. Since numerical ray tracing is computationally intensive, we have developed simplified formulation for this study. The suggested model of compound parabolic layer allows us to analytically calculate ray paths. Changes in the shape of the ionogram cusp caused by varying TID characteristics are examined.

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Ларюнин, Олег, and Oleg Laryunin. "Numerical synthesis of ionograms in horizontally inhomogeneous ionosphere on the basis of compound parabolic layer model." Solnechno-Zemnaya Fizika 2, no. 3 (September 17, 2016): 52–58. http://dx.doi.org/10.12737/18656.

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Characteristic U-shaped traces cusps on ionograms have been identified as off-angle echoes from sloping electron density contours caused by the presence of traveling ionospheric disturbances (TIDs). Dynamics of the cusps is associated with horizontal drift of the disturbances. A potential for reducing calculation time in numerical synthesis of vertical ionograms is under discussion. Since numerical ray tracing is expensive in terms of computer time, we have developed simplified formulation for this study. The suggested model of compound parabolic layer allows us to analytically calculate ray paths. Changes in the shape of the ionogram cusp caused by varying TID characteristics are examined.

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10

Batista, Maria do Carmo de S., Roberto S. de Castro, Eneida W. Rego, Fernando Aécio de A. Carvalho, Silvana Maria M. S. Silva, Cleyton C. D. Carvalho, and Franklin Riet-Correa. "Hemograma, proteinograma, ionograma e dosagens bioquímicas e enzimáticas de ovinos acometidos por conidiobolomicose no nordeste do Brasil." Pesquisa Veterinária Brasileira 29, no. 1 (January 2009): 17–24. http://dx.doi.org/10.1590/s0100-736x2009000100002.

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Foram realizados eritrogramas, leucogramas, dosagens séricas de proteínas totais, albumina, globulinas, cálcio, fósforo, magnésio, cloretos, uréia, creatinina, bilirrubina total, direta e indireta e atividade sérica de aspartato aminotransferase (AST), fosfatase alcalina (FA) e gama-glutamiltransferase (GGT) de 56 ovinos afetados por conidiobolomicose e de 371 ovinos sadios provenientes dos mesmos rebanhos dos casos da doença. Os resultados revelaram que os ovinos com conidiobolomicose apresentam anemia arregenerativa normocítica normocrômica, leucocitose com neutrofilia e discreto desvio à esquerda regenerativo, com elevação da relação neutrófilo:linfócito, monocitose moderada, trombocitose, hipoproteinemia (hipoglobulinemia), hipomagnesemia, hipocalcemia e elevação dos teores de fósforo. As atividades séricas de AST e GGT estavam aumentadas e as de FA diminuídas. Não houve alteração nos níveis de uréia e creatinina, mas ocorreu hipoglicemia e hiperbilirrubinemia. Estes resultados podem ser utilizados para estudos experimentais da doença, em ensaios com tratamentos e para identificar casos precoces da enfermidade que não apresentem sinais clínicos. Além disso, os valores encontrados em 371 ovinos deslanados hígidos podem ser utilizados como valores referenciais para este tipo de ovinos na região semi-árida do Brasil.

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11

Zhbankov, G. A. "DEVELOPMENT OF METHODS OF CALCULATIONS OF N(h)-PROFILES OF THE IONOSPHERE BASED ON THE DATA OF IONOGRAMS OF VERTICAL SENSING." RADIO COMMUNICATION TECHNOLOGY, no. 46 (September 30, 2020): 7–18. http://dx.doi.org/10.33286/2075-8693-2020-46-7-18.

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Two new methods are proposed for calculating the N(h)-profiles of the ionosphere from the data of vertical sounding ionograms based on numerical trajectory calculations in a mag-netically active medium. It has been shown experimentally that the model ionogram calculat-ed from the profiles obtained by both described methods is almost exactly consistent with the experimental one. Depending on the task, you can specify the choice of method. With some modification, they can be used as an automatic procedure for calculating N(h)- profiles.

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12

Yusupov, Kamil M., and Nataliya V. Bakhmetieva. "Sporadic E Layer with a Structure of Double Cusp in the Vertical Sounding Ionogram." Atmosphere 12, no. 9 (August 25, 2021): 1093. http://dx.doi.org/10.3390/atmos12091093.

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In this study, we analyzed a large number of vertical sounding ionograms, obtained by the mid-latitude Cyclone ionosonde (55.85° N; 48.8° E) of Kazan (Volga Region) Federal University, which operates in a rapid-run mode of ionograms (1 ionogram per minute). Ionograms with a sporadic E layer type c, which have an unusual double cusp on the trace from the sporadic layer, were found among them. We attempted to simulate this unusual double cusp trace shape. Model calculations were performed to clarify the reasons for the appearance of the double cusp and to determine the shape of the lower part of the E and Es layers. The simulation was performed by fitting the profile of the electron densities of the E and Es layers, calculating the virtual reflection heights based on the refractive index using the Appleton-Hartree formula, and comparing them with the virtual heights of the layers on the ionogram. An estimate of the half-thickness of the lower part of the Es-layer was obtained. The possible reasons for the appearance of a trace with a double cusp of the Es layer are discussed. We assumed that the possible reasons for this phenomenon were the stratification of the E layer, and the interaction between the E and F layers in the form of descending or intermediate layers and atmospheric wave propagation. As an illustration of these phenomena, examples of an intermediate (descending) sporadic E layer and stratification of the E region and the Es layer are given according to observations of the lower ionosphere. These examples were obtained through the resonant scattering of probe radio waves by artificial periodic irregularities (API technique) of the ionospheric plasma, performed on the SURA mid-latitude heating facility (56.1° N; 46.1° E). The scattering of probe radio waves on the APIs generated by the heating facility made it possible to study various phenomena in the Earth’s ionosphere.

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13

Yusupov, Kamil, John Mathews, Takashi Maruyama, Adel Akchurin, Maksim Tolstikov, Oleg Sherstyukov, Elena Filippova, and Anvar Safiullin. "AMPLITUDE VARIATIONS OF THE REFLECTED SIGNAL DURING VERTICAL SOUNDING OF THE IONOSPHERE AT MIDDLE LATITUDES." Solnechno-Zemnaya Fizika 6, no. 3 (September 22, 2020): 88–98. http://dx.doi.org/10.12737/szf-63202010.

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In this paper, we discuss the main types of quasiperiodic variations in amplitudes of a reflected signal during vertical sounding of the ionosphere at middle latitudes. The initial experimental data is vertical sounding ionograms obtained by the Cyclone ionosonde. The ionosonde is located in Kazan (59°, 49°) and in standard mode allows us to receive one ionogram per minute. In the analysis, methods are used to visualize a large flow of ionograms in the form of final summary maps of the state of the ionosphere (A-, H-, As-maps). We give typical examples of quasiperiodic variations in amplitudes of a reflected signal in ionograms and on A-maps for various types of multipath beatings (polarization and due to signal scattering by ionospheric irregularities). Frequency properties of such beatings are used to estimate the difference in virtual reflection heights between modes of different polarizations with high accuracy, which makes it possible to refine the form of the electron density profile of the lower ionosphere. We have detected a phenomenon rare for the mid-latitude Es layer — beatings of two O modes with different virtual reflection heights. We also present features of quasiperiodic variations in amplitudes of a reflected signal on traces of the transient Es layer. We study possible causes of the appearance of such beatings.

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Yusupov, Kamil, John Mathews, Takashi Maruyama, Adel Akchurin, Maksim Tolstikov, Oleg Sherstyukov, Elena Filippova, and Anvar Safiullin. "AMPLITUDE VARIATIONS OF THE REFLECTED SIGNAL DURING VERTICAL SOUNDING OF THE IONOSPHERE AT MIDDLE LATITUDES." Solar-Terrestrial Physics 6, no. 3 (September 22, 2020): 72–80. http://dx.doi.org/10.12737/stp-63202010.

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In this paper, we discuss the main types of quasiperiodic variations in amplitudes of a reflected signal during vertical sounding of the ionosphere at middle latitudes. The initial experimental data is vertical sounding ionograms obtained by the Cyclone ionosonde. The ionosonde is located in Kazan (59°, 49°) and in standard mode allows us to receive one ionogram per minute. In the analysis, methods are used to visualize a large flow of ionograms in the form of final summary maps of the state of the ionosphere (A-, H-, As-maps). We give typical examples of quasiperiodic variations in amplitudes of a reflected signal in ionograms and on A-maps for various types of multipath beatings (polarization and due to signal scattering by ionospheric irregularities). Frequency properties of such beatings are used to estimate the difference in virtual reflection heights between modes of different polarizations with high accuracy, which makes it possible to refine the form of the electron density profile of the lower ionosphere. We have detected a phenomenon rare for the mid-latitude Es layer — beatings of two O modes with different virtual reflection heights. We also present features of quasiperiodic variations in amplitudes of a reflected signal on traces of the transient Es layer. We study possible causes of the appearance of such beatings.

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15

Mochalov, Vladimir, and Anastasia Mochalova. "Application of deep learning methods to predict ionosphere parameters in real time." E3S Web of Conferences 196 (2020): 02007. http://dx.doi.org/10.1051/e3sconf/202019602007.

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In this paper, the previously obtained results on recognition of ionograms using deep learning are expanded to predict the parameters of the ionosphere. After the ionospheric parameters have been identified on the ionogram using deep learning in real time, we can predict the parameters for some time ahead on the basis of the new data obtained Examples of predicting the ionosphere parameters using an artificial recurrent neural network architecture long short-term memory are given. The place of the block for predicting the parameters of the ionosphere in the system for analyzing ionospheric data using deep learning methods is shown.

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Soudre, Fabienne Marie, Alice Kiba, Arnaud Kouraogo, Raoul Karfo, Salam Tiendrebeogo, Augustin Kyetega, Dieudonné Sire, Elie Kabre, and Jean Sakande. "Profil de l’ionogramme sanguin chez les enfants brûlés du Centre Hospitalier Universitaire Pédiatrique Charles de Gaulle de Ouagadougou (Burkina Faso)." International Journal of Biological and Chemical Sciences 15, no. 2 (June 21, 2021): 426–36. http://dx.doi.org/10.4314/ijbcs.v15i2.5.

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Les brûlures de l’enfant peuvent être à l’origine de troubles ioniques graves, entrainant une morbi-mortalité importante. Ce travail avait pour objectif de décrire les perturbations de l’ionogramme sanguin chez les enfants brûlés, afin de contribuer à l’amélioration des soins. Il s’est agi d’une étude transversale rétrospective allant du 01 janvier 2017 au 30 juin 2019. Ont été inclus les enfants hospitalisés dans le service de chirurgie du CHU pédiatrique Charles de Gaulle pour brûlure et chez lesquels un ionogramme sanguin a été réalisé. L’étude a porté sur 212 enfants, avec un âge moyen de 38,52 mois et un sex ratio de 1,12. La surface corporelle brûlée moyenne était de 26,60% et le délai moyen d’admission de 5,71 heures. La mortalité était de 16,98%. L’ionogramme sanguin à l’entrée a retrouvé une hyponatrémie (27,88%), une hypobicarbonatémie (53,95%), une hypoprotidémie (26,67%) et une hyperchlorémie (53,59%). Au contrôle, ces troubles ioniques étaient toujours présents. S’y sont associées une hypocalcémie (30,43%), une hypomagnésémie (27,27%) et une hyperphosphatémie (28,79%). La natrémie, la bicarbonatémie et la protidémie à l’entrée étaient significativement plus basses chez les patients décédés. Les brûlures de l’enfant sont fréquentes. Leur évolution est marquée par des perturbations de l’ionogramme sanguin et une mortalité élevée.Mots clés : Brûlure, Ionogramme sanguin, Enfants, Burkina Faso. English title: Blood ionogram profile in burned children at the Charles de Gaulle University Pediatric Hospital of Ouagadougou (Burkina Faso)Burns in children can be the cause of serious ionic disorders, leading to significant morbidity and mortality. The aim of this study was to describe the disturbances in the blood ionogram of burnt children, in order to contribute to the improvement of care. This was a retrospective cross-sectional study from 01 January 2017 to 30 June 2019. Children hospitalised in the surgery department of the Charles de Gaulle Pediatric University Hospital for burns and in whom a blood ionogram was carried out were included. Our study involved 212 children, with an average age of 38.52 months and a sex ratio of 1.12. The average body surface area burned was 26.60% and the average admission time was 5.71 hours. Mortality was 16.98%. The blood ionogram at the entrance showed hyponatremia (27.88%), hypobicarbonatremia (53.95%), hypoprotidemia (26.67%) and hyperchloremia (53.59%). At the control, these ionic disorders were still present. They were associated with hypocalcaemia (30.43%), hypomagnesemia (27.27%) and hyperphosphatemia (28.79%). Natremia, bicarbonateemia and protidemia were significantly lower on admission in patients who died in the course of the evolution. Childhood burns are frequent at the CHUP-CDG; their evolution is marked by disturbances of the blood ionogram and high mortality.Keywords: Burns, Blood Ionogram, Children, Burkina Faso.

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17

Bilitza, Dieter, Xueqin Huang, Bodo W. Reinisch, Robert F. Benson, H. Kent Hills, and William B. Schar. "Topside Ionogram Scaler With True Height Algorithm (TOPIST): Automated processing of ISIS topside ionograms." Radio Science 39, no. 1 (January 16, 2004): n/a. http://dx.doi.org/10.1029/2002rs002840.

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Yuan, Zhigang, Baiqi Ning, Weixing Wan, and Hong Yuan. "Acquirement and analysis of Doppler ionograms with high accuracy in the ionogram mode from Digisonde 256." Radio Science 39, no. 2 (April 2004): n/a. http://dx.doi.org/10.1029/2002rs002779.

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Бернгардт, Олег, Oleg Berngardt, Татьяна Бубнова, Tatyana Bubnova, Алексей Подлесный, and Aleksey Podlesnyi. "Automatic estimation of dynamics of ionospheric disturbances with 1–15 minute lifetimes as derived from ISTP SB RAS fast chirp-ionosonde data." Solnechno-Zemnaya Fizika 4, no. 1 (March 29, 2018): 76–84. http://dx.doi.org/10.12737/szf-41201807.

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We propose and test a method of analyzing ionograms of vertical ionospheric sounding, which is based on detecting deviations of the shape of an ionogram from its regular (averaged) shape. We interpret these deviations in terms of reflection from the electron density irregularities at heights corresponding to the effective height. We examine the irregularities thus discovered within the framework of a model of a localized uniformly moving irregularity, and determine their characteristic parameters: effective heights and observed vertical velocities. We analyze selected experimental data for three seasons (spring, winter, autumn) obtained nearby Irkutsk with a fast chirp ionosonde of ISTP SB RAS in 2013–2015. The analysis of six days of observations conducted in these seasons has shown that in the observed vertical drift of the irregularities there are two characteristic distributions: wide velocity distribution with nearly 0 m/s mean and with standard deviation of ~250 m/s and narrow distribution with nearly –160 m/s mean. The analysis has demonstrated the effectiveness of the proposed algorithm for the automatic analysis of vertical sounding data with high repetition rate.

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Buresova, D., V. Krasnov, Ya Drobzheva, J. Lastovicka, J. Chum, and F. Hruska. "Assessing the quality of ionogram interpretation using the HF Doppler technique." Annales Geophysicae 25, no. 4 (May 8, 2007): 895–904. http://dx.doi.org/10.5194/angeo-25-895-2007.

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Abstract. The first joint common volume measurements by the Digisonde Portable Sounder (DPS-4) and a new Doppler type system has been run at the Pruhonice ionospheric observatory (49.99° N, 14.54° E) since January 2004. The measurement of the Doppler shift is carried out continuously on a frequency of 3.6 MHz, thus the radio wave is reflected predominantly from the ionospheric F layer. To compare digisonde measurements with the Doppler data, a phase path was calculated from both Doppler and digisonde records. Under stormy conditions and in the case where a sporadic E layer was present, a significant disagreement between both measurements has been found. The discrepancies could be related to the uncertainties of the observational inputs and to the interpretation of the digisonde data. The comparison of the phase paths shows that during geomagnetically quiet days, in the absence of the sporadic E layer, and when high quality ionograms are available and correctly scaled, the electron density N(h) profiles, calculated by the Automatic Real Time Ionogram Scaler with True height algorithm (ARTIST), can be considered reliable.

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Yuan, Zhigang, Baiqi Ning, Weixing Wan, and Hong Yuan. "Correction to “Acquirement and analysis of Doppler ionograms with high accuracy in the ionogram mode from Digisonde 256”." Radio Science 39, no. 3 (June 2004): n/a. http://dx.doi.org/10.1029/2004rs003085.

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22

Klipp, Telmo dos Santos, Adriano Petry, Jonas Rodrigues de Souza, Eurico Rodrigues de Paula, Gabriel Sandim Falcão, and Haroldo Fraga de Campos Velho. "Ionosonde total electron content evaluation using International Global Navigation Satellite System Service data." Annales Geophysicae 38, no. 2 (March 18, 2020): 347–57. http://dx.doi.org/10.5194/angeo-38-347-2020.

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Abstract. In this work, a period of 2 years (2016–2017) of ionospheric total electron content (ITEC) from ionosondes operating in Brazil is compared to the International GNSS (Global Navigation Satellite System) Service (IGS) vertical total electron content (vTEC) data. Sounding instruments from the National Institute for Space Research (INPE) provided the ionograms used, which were filtered based on confidence score (CS) and C-Level flag evaluation. Differences between vTEC from IGS maps and ionosonde TEC were accumulated in terms of root mean squared error (RMSE). As expected, we noticed that the ITEC values provided by ionosondes are systematically underestimated, which is attributed to a limitation in the electron density modeling for the ionogram topside that considers a fixed scale height, which makes density values decay too rapidly above ∼800 km, while IGS takes in account electron density from GNSS stations up to the satellite network orbits. The topside density profiles covering the plasmasphere were re-modeled using two different approaches: an optimization of the adapted α-Chapman exponential decay that includes a transition function between the F2 layer and plasmasphere and a corrected version of the NeQuick topside formulation. The electron density integration height was extended to 20 000 km to compute TEC. Chapman parameters for the F2 layer were extracted from each ionogram, and the plasmaspheric scale height was set to 10 000 km. A criterion to optimize the proportionality coefficient used to calculate the plasmaspheric basis density was introduced in this work. The NeQuick variable scale height was calculated using empirical parameters determined with data from Swarm satellites. The mean RMSE for the whole period using adapted α-Chapman optimization reached a minimum of 5.32 TECU, that is, 23 % lower than initial ITEC errors, while for the NeQuick topside formulation the error was reduced by 27 %.

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De Vivero Camacho, Rodrigo, Nelson Muñoz Álvarez, Cesar Redondo Bermúdez, Nelson Alvis Guzmán, and Luz Esthella Tovar Correa. "Enfermedad de menetrier asociada a infección por citomegalovirus." Revista Ciencias Biomédicas 6, no. 2 (November 24, 2020): 354–59. http://dx.doi.org/10.32997/rcb-2015-2964.

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Introducción: la enfermedad de Menetrier es poco frecuente en pediatría, sin etiología establecida, se le ha asociado a infecciones en su mayoría virales y bacterianas capaces de generar un proceso inflamatorio que desencadena pérdida de proteínas con clínica de dolor abdominal, náuseas, vómitos y edemas. Con resolución espontánea luego de4-6 semanas sin secuelas. El objetivo es describir un caso de enfermedad de Menetrieren pediatría.Caso clínico: preescolar masculino de tres años edad, sin antecedentes perinatales, con cuadro de cinco días de vómitos, diarrea abundante, no disentérica y fiebre; en los últimos dos días con edema bipalpebral. Luego del examen coprológico presentó: quistes de Giardia lamblia, manejado con metronidazol. Es remitido al Hospital Infantil Napoleón Franco Pareja en Cartagena-Colombia por evidencia de edema bipalpebral.En valoración de urgencias se encontró niño en buenas condiciones generales, con facie de enfermedad aguda, con signos vitales estables, hemograma con ligera leucocitosis, extendido de sangre periférica con granulaciones tóxicas en los neutrófilos, parcial de orina sin proteinuria, albúmina sérica 1.26 gr/dl, transaminasas normal, ionograma normal, perfil lipídico normal, ecografía abdominal con moderada distensión de asas intestinales, endoscopia digestiva alta con hipertrofia de pliegues en mucosa de cuerpogástrico, hiperemia y friabilidad sin erosiones. La biopsia mostró gastropatía crónica activa con marcada hiperplasia foveolar, compatible con enfermedad de Menetrier. Durante su estancia se administró albúmina 1 gr/kg por cuatro días con resolución del edema y proteinograma, se da egreso con niveles de albúmina normales y en sus controles posteriores, el niño continuó asintomático. Con resolución completa de su cuadro clínico.Conclusión: la enfermedad de Menetrier en pediatría se autolimita con una duración de 4 – 6 semanas puede cursar con manifestaciones de dolor abdominal, vómitos, náuseas y edemas. Con las manifestaciones clínicas y hallazgo endoscópico de hipertrofia de pliegues de fondo y cuerpo gástrico se puede presumir el diagnóstico. Se confirma con reporte histopatológico, el curso natural de esta enfermedad es benigno, con resolución completa de los síntomas. Rev.cienc.biomed. 2015; 6(2):354-359

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Scotto, Carlo, and Dario Sabbagh. "The Accuracy of Real-Time hmF2 Estimation from Ionosondes." Remote Sensing 12, no. 17 (August 19, 2020): 2671. http://dx.doi.org/10.3390/rs12172671.

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A total of 4991 ionograms recorded from April 1997 to December 2017 by the Millstone Hill Digisonde (42.6°N, 288.5°E) were considered, with simultaneous Ne(h)[ISR] profiles recorded by the co-located Incoherent Scatter Radar (ISR). The entire ionogram dataset was scaled with both the Autoscala and ARTIST programs. The reliability of the hmF2 values obtained by ARTIST and Autoscala was assessed using the corresponding ISR values as a reference. Average errors Δ and the root mean square errors RMSE were computed for the whole dataset. Data analysis shows that both the Autoscala and ARTIST systems tend to underestimate hmF2 values with |Δ| in all cases less than 10 km. For high magnetic activity ARTIST offers better accuracy than Autoscala, as evidenced by RMSE[ARTIST] < RMSE[Autoscala], under both daytime and nighttime conditions, and considering all hours of the day. Conversely, under low and medium magnetic activity Autoscala tends to estimate hmF2 more accurately than the ARTIST system for both daytime and nighttime conditions, when RMSE[Autoscala] < RMSE[ARTIST]. However, RMSE[Autoscala] slightly exceeds RMSE[ARTIST] for the day as a whole. RMSE values are generally substantial (RMSE > 16 km in all cases), which places a limit on the results obtainable with real-time models that ingest ionosonde data.

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Liu, L., W. Wan, and B. Ning. "A study of the ionogram derived effective scale height around the ionospheric <I>hm</I>F2." Annales Geophysicae 24, no. 3 (May 19, 2006): 851–60. http://dx.doi.org/10.5194/angeo-24-851-2006.

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Abstract. The diurnal, seasonal, and solar activity variations of the ionogram derived scale height around the ionospheric F-layer peak (Hm) are statistically analyzed at Wuhan (114.4° E, 30.6° N) and the yearly variations of Hm are also investigated for Wuhan and 12 other stations where Hm data are available. Hm, as a measure of the slope of the topside electron number density profiles, is calculated from the bottomside electron density profiles derived from vertical sounding ionograms using the UMLCAR SAO-Explorer. Results indicate that the value of median Hm increases with increasing solar flux. Hm is highest in summer and lowest in winter during the daytime, while it exhibits a much smaller seasonal variation at night. A common feature presented at these 13 stations is that Hm undergoes a yearly annual variation with a maximum in summer during the daytime. The annual variation becomes much weaker or disappears from late night to pre-sunrise. In addition, a moderate positive correlation is found between Hm with hmF2 and a strong correlation between the bottomside thickness parameter B0 and Hm. The latter provides a new and convenient way for empirical modeling the topside ionospheric shape only from the established B0 parameter set.

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Chen, Gang, ZhengYu Zhao, YuanNong Zhang, GuoBin Yang, Chen Zhou, Shuo Huang, Ting Li, Ning Li, and HengQing Sun. "Application of the oblique ionogram as vertical ionogram." Science China Technological Sciences 55, no. 5 (March 21, 2012): 1240–44. http://dx.doi.org/10.1007/s11431-012-4795-8.

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Kuo, Spencer. "Linear and Nonlinear Plasma Processes in Ionospheric HF Heating." Plasma 4, no. 1 (February 23, 2021): 108–44. http://dx.doi.org/10.3390/plasma4010008.

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Featured observations of high frequency (HF) heating experiments are first introduced; the uniqueness of each observation is presented; the likely cause and physical process of each observed phenomenon instigated by the HF heating are discussed. A special point in the observations, revealed through the ionograms, is the competition between the Langmuir parametric instability and upper hybrid parametric instability excited in the heating experiments and the impact of the natural cusp at foE (the peak plasma frequency of the ionospheric E region) on the competition. The ionograms also infer the generation of Langmuir and upper hybrid cavitons. Ray tracing theory is formulated. With and without the appearance of large-scale field-aligned density irregularities in the background ionosphere, ray trajectories of the ordinary mode (O-mode) and extraordinary mode (X-mode) sounding pulses are calculated numerically. The results explain the artificial Spread-F recorded by the digisondes in the heating experiments. Parametric instabilities, which are the directly relevant processes to achieve effective heating of the ionospheric F region, are formulated and analyzed. The threshold fields and growth rates of Langmuir and upper hybrid parametric instabilities are derived as the theoretical basis of many radar observations and electron-plasma wave interactions. Harmonic cyclotron resonance interaction processes between electrons and upper hybrid waves are introduced. Formulation and analysis are presented. The numerical results show that ultra-energetic electrons are generated. These electrons enhance airglow at 777.4 nm as well as cause ionization. Physical processes leading to the generation of artificial ionization layers are discussed. The nonlinear Schrodinger equation governing the nonlinear evolution of Langmuir waves and upper hybrid waves are derived and solved. The nonlinear periodic and solitary solutions of the equations are obtained. The localized Langmuir and upper hybrid waves generated by the HF heater form cavitons near the HF reflection layer and near the upper hybrid resonance layer, which induce bumps in the virtual height spread of the ionogram trace similar to that induced by the density cusp at E-F1 transition layer; the down-going Langmuir waves and upper hybrid waves evolve into nonlinear periodic waves propagating along the magnetic field, which backscatter incoherently the sounding pulses to cause downward virtual height spread.

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Mochalov, Vladimir, and Anastasia Mochalova. "Applying general markup knowledge to analyze ionograms of various ionosondes." E3S Web of Conferences 196 (2020): 03002. http://dx.doi.org/10.1051/e3sconf/202019603002.

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In order to improve the quality of recognition of ionograms, the use of general knowledge about the reference marking of ionograms at various points of installation of ionosondes of the same type is considered. On the basis of reference markings from two ionosondes, deep neural networks were trained to highlight reflection traces from different layers of the ionosphere. The resulting deep neural networks have been successfully applied to recognize ionograms of another type of ionosonde. The results of recognition are presented.

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Rejfek, Luboš, Zbyšek Mošna, Daniel Kouba, Josef Boška, and Dalia Burešová. "Application of Digital Filters to Check Quality of the Automatically Scaled Ionograms." Journal of Electrical Engineering 66, no. 3 (May 1, 2015): 164–68. http://dx.doi.org/10.2478/jee-2015-0026.

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Abstract The ionospheric observatory Pruhonice serves to monitor the state of ionosphere using ground-based vertical sounding instrument - the Digisonde DPS-4D. Measured ionograms are automatically evaluated (scaled) and basic characteristics are derived. The ionograms and the scaled parameters are sent to the international databases. Especially during disturbed conditions the automatic scaling could give unreliable results. This paper presents simple method how to detect accidental errors in automatic scaling based on the parameters derived from ionograms and on an application of the finite impulse response filters.

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Reinisch, B. W., A. Ya Feldstein, and H. Sizun. "Digital ionogram data." Advances in Space Research 10, no. 8 (January 1990): 127–30. http://dx.doi.org/10.1016/0273-1177(90)90199-a.

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Chandra, H., S. Sharma, C. V. Devasia, K. S. V. Subbarao, R. Sridharan, J. H. Sastri, and J. V. S. V. Rao. "Sporadic-E associated with the Leonid meteor shower event of November 1998 over low and equatorial latitudes." Annales Geophysicae 19, no. 1 (January 31, 2001): 59–69. http://dx.doi.org/10.5194/angeo-19-59-2001.

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Abstract. Rapid radio soundings were made over Ahmedabad, a low latitude station during the period 16–20 November 1998 to study the sporadic-E layer associated with the Leonid shower activity using the KEL Aerospace digital ionosonde. Hourly ionograms for the period 11 November to 24 November were also examined during the years from 1994 to 1998. A distinct increase in sporadic-E layer occurrence is noticed on 17, 18 and 19 November from 1996 to 1998. The diurnal variations of f0Es and fbEs also show significantly enhanced values for the morning hours of 18 and 19 November 1998. The ionograms clearly show strong sporadic-E reflections at times of peak shower activity with multiple traces in the altitude range of 100–140 km in few ionograms. Sporadic-E layers with multiple structures in altitude are also seen in some of the ionograms (quarter hourly) at Thumba, situated near the magnetic equator. Few of ionograms recorded at Kodaikanal, another equatorial station, also show sporadic- E reflections in spite of the transmitter power being significantly lower. These new results highlighting the effect of intense meteor showers in the equatorial and low latitude E-region are presented.Key words. Ionosphere (equatorial ionosphere) – Radio science (ionospheric physics)

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Schmitt, François. "Ionogramme." EMC - Biologie Médicale 1, no. 1 (January 2006): 1–4. http://dx.doi.org/10.1016/s2211-9698(06)76088-5.

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Романова, Елена, Elena Romanova, Галина Котович, Galina Kotovich, Сергей Пономарчук, Sergey Ponomarchuk, Антон Ким, and Anton Kim. "Modeling z-shaped disturbance along the Pedersen ray of oblique sounding ionogram using adaptation of IRI to experimental data." Solnechno-Zemnaya Fizika 2, no. 4 (December 20, 2016): 43–53. http://dx.doi.org/10.12737/21815.

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We present the results of numerical modeling of a traveling ionospheric disturbance that causes z-shaped bends at the Pedersen ray of oblique incidence ionograms. The results of trajectory synthesis of oblique incidence ionograms are given for the ionosphere, taking into account the traveling ionospheric disturbance. In the work, we use the International Reference Ionosphere, adapted to experimental data, and the Model of Ionosphere and Plasmasphere.

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Scott, Christopher J., Shannon Jones, and Luke A. Barnard. "Inferring thermospheric composition from ionogram profiles: a calibration with the TIMED spacecraft." Annales Geophysicae 39, no. 2 (March 19, 2021): 309–19. http://dx.doi.org/10.5194/angeo-39-309-2021.

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Abstract. We present a method for augmenting spacecraft measurements of thermospheric composition with quantitative estimates of daytime thermospheric composition below 200 km, inferred from ionospheric data, for which there is a global network of ground-based stations. Measurements of thermospheric composition via ground-based instrumentation are challenging to make, and so details about this important region of the upper atmosphere are currently sparse. The visibility of the F1 peak in ionospheric soundings from ground-based instrumentation is a sensitive function of thermospheric composition. The ionospheric profile in the transition region between F1 and F2 peaks can be expressed by the “G” factor, a function of ion production rate and loss rates via ion–atom interchange reactions and dissociative recombination of molecular ions. This in turn can be expressed as the square of the ratio of ions lost via these processes. We compare estimates of the G factor obtained from ionograms recorded at Kwajalein (9∘ N, 167.2∘ E) for 25 times during which the Thermosphere, Ionosphere, Mesosphere, Energetics and Dynamics (TIMED) spacecraft recorded approximately co-located measurements of the neutral thermosphere. We find a linear relationship between G and the molecular-to-atomic composition ratio, with a gradient of 2.55±0.40. Alternatively, using hmF1 values obtained by ionogram inversion, this gradient was found to be 4.75±0.4. Further, accounting for equal ionisation in molecular and atomic species yielded a gradient of 4.20±0.8. This relationship has potential for using ground-based ionospheric measurements to infer quantitative variations in the composition of the neutral thermosphere via a relatively simple model. This has applications in understanding long-term change and the efficacy of the upper atmosphere on satellite drag.

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35

Ким, Антон, Anton Kim, Елена Романова, Elena Romanova, Галина Котович, Galina Kotovich, Сергей Пономарчук, and Sergey Ponomarchuk. "Modeling z-shaped disturbance along the Pedersen ray of oblique sounding ionogram using adaptation of IRI to experimental data." Solar-Terrestrial Physics 2, no. 4 (February 2, 2017): 55–69. http://dx.doi.org/10.12737/24273.

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We present the results of numerical modeling of a traveling ionospheric disturbance that causes z-shaped bends at the Pedersen ray of oblique incidence ionograms. The results of trajectory synthesis of oblique incidence ionograms are given for the ionosphere, taking into account the traveling ionospheric disturbance. In the work, we use the International Reference Ionosphere, adapted to experimental data, and the Global Model of the Ionosphere and Plasmasphere.

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36

Bogomaz, O., M. Shulha, D. Kotov, A. Koloskov, and A. Zalizovski. "An artificial neural network for analysis of ionograms obtained by ionosonde at the Ukrainian Antarctic Akademik Vernadsky station." Ukrainian Antarctic Journal, no. 2 (December 2020): 59–67. http://dx.doi.org/10.33275/1727-7485.2.2020.653.

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The article presents the developed artificial neural network for F2 ionosphere layer traces scaling on ionograms obtained using the IPS-42 ionosonde installed at the Ukrainian Antarctic Akademik Vernadsky station. The parameters of the IPS-42 ionosonde and the features of the data obtained with it, in particular the format of the output files, are presented. The advantages of using an artificial neural network for identification of traces on ionograms are demonstrated. Usually, an automatic scaling of the ionograms requires a lot of machine time however implementation of an artificial neural network speeds up computations significantly allowing to process incoming ionograms even in the real time mode. The choice of architecture of an artificial neural network is substantiated. The U-Net architecture was chosen. The method of creating and training the neural network is described. The artificial neural network development process included choosing the number of layers, types of activation functions, optimization method and input layer size. Software developed was written in Python programming language with use of the Keras library. Examples of data used for training of the artificial neural network are shown. The results of testing an artificial neural network are presented. The data obtained with the artificial neural network are compared with the results of manual processing of ionograms. Data for training the artificial neural network were obtained in March, 2017 using the IPS-42 ionosonde installed at the Ukrainian Antarctic Akademik Vernadsky station; data for testing were obtained in 2017 and 2020. The developed artificial neural network has minor flaws but they are easily eliminated by retraining the network on a more representative dataset (obtained in various years and seasons). The general results of testing indicate good prospects in further developing this artificial neural network and software for working with it.

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Ippolito, Alessandro, David Altadill, Carlo Scotto, and Estefania Blanch. "Oblique Ionograms Automatic Scaling Algorithm OIASA application to the ionograms recorded by Ebro observatory ionosonde." Journal of Space Weather and Space Climate 8 (2018): A10. http://dx.doi.org/10.1051/swsc/2017042.

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The oblique ionograms automatic scaling algorithm (OIASA), developed at the INGV for the identification of trace of oblique ionograms, allows the determination of the maximum usable frequency (MUF) for communication between the transmitter and receiver, automatically rejecting poor quality ionograms. A test of the algorithm using data from a campaign of oblique soundings between Dourbes (50.1°N, 4.6°E) and Roquetes (40.8°N, 0.5°E) has been performed. Oblique soundings from three different campaigns have been studied, covering different geomagnetic conditions, in order to study the behavior of the autoscaling algorithm under quiet and perturbed geomagnetic periods. The reported results demonstrate that OIASA performance is not influenced by geomagnetic or ionospheric activity conditions. This demonstrates a satisfactory performance of the automatic scaling algorithm, even under different geomagnetic conditions, the potential application of OIASA as a near-real-time tool for ionospheric monitoring purposes, and its performance for tracking ionospheric effects caused by space weather events.

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38

Scotto, Carlo, and Michael Pezzopane. "Automatic scaling of polar ionograms." Antarctic Science 24, no. 1 (September 23, 2011): 88–94. http://dx.doi.org/10.1017/s0954102011000587.

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AbstractThe Istituto Nazionale di Geosifica e Vulcanologia (INGV) software for automatic scaling of ionograms (Autoscala) was improved by introducing a system to identify D region absorption events, spread-F condition (frequency spreading in the F region), and Z-ray propagation. The algorithm was applied to a series of ionograms recorded by the AIS-INGV (Advanced Ionospheric Sounder-INGV) ionosonde installed at the Mario Zucchelli Station (74.7°S, 164.1°E), Terra Nova Bay, Antarctica. Critical cases are shown to illustrate the behaviour of the software.

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Chen, Ziwei, Shun Wang, Shunrong Zhang, Guangyou Fang, and Jinsong Wang. "Automatic scaling ofFlayer from ionograms." Radio Science 48, no. 3 (May 2013): 334–43. http://dx.doi.org/10.1002/rds.20038.

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40

Fox, Matthew W., and Craig Blundell. "Automatic scaling of digital ionograms." Radio Science 24, no. 6 (November 1989): 747–61. http://dx.doi.org/10.1029/rs024i006p00747.

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41

Arikan, F., S. Salous, and O. Arikan. "Algorithm for high quality ionograms." Electronics Letters 36, no. 11 (2000): 985. http://dx.doi.org/10.1049/el:20000725.

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Chen, Ziwei, Shun Wang, Guangyou Fang, and Jinsong Wang. "Ionograms denoising via curvelet transform." Advances in Space Research 52, no. 7 (October 2013): 1289–96. http://dx.doi.org/10.1016/j.asr.2013.07.004.

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43

Ippolito, Alessandro, Carlo Scotto, Matthew Francis, Alessandro Settimi, and Claudio Cesaroni. "Automatic interpretation of oblique ionograms." Advances in Space Research 55, no. 6 (March 2015): 1624–29. http://dx.doi.org/10.1016/j.asr.2014.12.025.

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44

Ponomarchuk, Sergey, and Maksim Penzin. "INVERSION OF BACKSCATTER IONOGRAMS INTO QUASI-PARABOLIC IONOSPHERIC LAYER PARAMETERS." Solar-Terrestrial Physics 6, no. 3 (September 22, 2020): 67–71. http://dx.doi.org/10.12737/stp-63202009.

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We present an inversion scheme of the backscatter signal leading edge into parameters of the quasi-parabolic electron density profile, which is based on the comparison of experimental and calculated minimum delays of scattered signals with corresponding distance to the skip zone border. Input parameters are frequency dependences of minimum group path of signal propagation, derived from processing and interpreting backscatter ionograms. For a fixed sounding frequency, the ionospheric parameter pair — the critical frequency and height of the F2-layer maximum — is defined as the intersection point of two curves representing solutions of minimization problems for discrepancy functionals of the minimum group path and the range to the skip zone border. Determining the ionospheric parameters by this inversion scheme on the sounding frequency grid allows us to construct a two-dimensional distribution of electron density in the direction of backscatter sounding.

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45

Maruyama, Takashi, Kamil Yusupov, and Adel Akchurin. "Interpretation of deformed ionograms induced by vertical ground motion of seismic Rayleigh waves and infrasound in the thermosphere." Annales Geophysicae 34, no. 2 (February 18, 2016): 271–78. http://dx.doi.org/10.5194/angeo-34-271-2016.

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Abstract. The vertical ground motion of seismic surface waves launches acoustic waves into the atmosphere and induces ionospheric disturbances. Disturbances due to Rayleigh waves near the short-period Airy phase appear as wavy fluctuations in the virtual height of an ionogram and have a multiple-cusp signature (MCS) when the fluctuation amplitude is increased. An extremely developed MCS was observed at Kazan, Russia, after the 2010 M 8.8 Chile earthquake. The ionogram exhibited steep satellite traces for which the virtual heights increased rapidly with frequency starting near the top of cusps and continuing for 0.1–0.2 MHz. This complicated ionogram was analyzed by applying a ray tracing technique to the radio wave propagation in the ionosphere that was perturbed by acoustic waves. Acoustic wavefronts were inclined by the effects of finite Rayleigh wave velocity and sound speed in the thermosphere. The satellite echo traces were reproduced by oblique returns from the inclined wavefronts, in addition to the nearly vertical returns that are responsible for the main trace.

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46

Paul, Adolf K. "Fregion tilts and ionogram analysis." Radio Science 20, no. 4 (July 1985): 959–71. http://dx.doi.org/10.1029/rs020i004p00959.

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47

Пономарчук, Сергей, Sergey Ponomarchuk, Владимир Куркин, Vladimir Kurkin, Максим Пензин, and Maksim Penzin. "Features of backscatter ionospheric sounding as studied with a chirp ionosonde." Solar-Terrestrial Physics 3, no. 3 (October 9, 2017): 54–60. http://dx.doi.org/10.12737/stp-33201706.

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We present the results of the studies of backscatter ionospheric sounding (BS) on the basis of a multipurpose chirp ionosonde developed in ISTP SB RAS. We analyze BS experimental data obtained during different seasons from 2005 to 2009. The accumulated dataset allows us to investigate features of BS signal propagation in various heliogeophysical conditions. To analyze and interpret BS signals on ionograms, we use the results of modeling of characteristics for chirp signals in the backscatter and oblique ionospheric sounding under a waveguide approach. We have revealed the most characteristic types of ionograms and have established conditions of appearance of a given type depending on the time of day, season, sounding direction, and medium conditions. In winter, spring, and autumn, the prevailing types of ionograms are those with BS signals corresponding to the propagation mode through reflection from the F layer. Signals reflected by E or Es layers are recorded during summer periods. At the same time, frequencies of the received signals are sufficiently large, and sometimes there are no reflections from the F layer.

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48

Пономарчук, Сергей, Sergey Ponomarchuk, Владимир Куркин, Vladimir Kurkin, Максим Пензин, and Maksim Penzin. "Features of backscatter ionospheric sounding as studied with a chirp ionosonde." Solnechno-Zemnaya Fizika 3, no. 3 (September 29, 2017): 61–69. http://dx.doi.org/10.12737/szf-33201706.

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We present the results of studies of backscatter ionospheric sounding (BS) on the basis of a multipurpose chirp ionosonde developed in ISTP SB RAS. We analyze BS experimental data obtained during different seasons from 2005 to 2009. The accumulated dataset allows us to investigate features of BS signal propagation in various heliogeophysical conditions. To analyze and interpret BS signals on ionograms, we use the results of modeling of characteristics for chirp signals in the backscatter and oblique ionospheric sounding under the waveguide approach. We have revealed the most characteristic types of ionograms and have established conditions of appearance of a given type depending on the time of day, season, sounding direction, and medium conditions. In winter, spring, and autumn, the prevailing types of ionograms are those with BS signals corresponding to the propagation mode through reflection from the F layer. Signals reflected by E or Es layers are recorded during summer periods. At the same time, frequencies of the received signals are sufficiently large, and sometimes there are no reflections from the F layer.

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49

Chen, J., J. A. Bennett, and P. L. Dyson. "Synthesis of oblique ionograms from vertical ionograms using quasi-parabolic segment models of the ionosphere." Journal of Atmospheric and Terrestrial Physics 54, no. 3-4 (March 1992): 323–31. http://dx.doi.org/10.1016/0021-9169(92)90011-9.

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50

Cabrera, M. A., M. Pezzopane, E. Zuccheretti, and R. G. Ezquer. "Satellite traces, range spread-F occurrence, and gravity wave propagation at the southern anomaly crest." Annales Geophysicae 28, no. 5 (May 18, 2010): 1133–40. http://dx.doi.org/10.5194/angeo-28-1133-2010.

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Abstract. Range spread-F (RSF) and occurrence of "satellite" traces prior to RSF onset were studied at the southern peak of the ionospheric equatorial anomaly (EA). Ionograms recorded in September 2007 at the new ionospheric station of Tucumán, Argentina (26.9° S, 294.6° E, dip latitude 15.5° S), by the Advanced Ionospheric Sounder (AIS) developed at the Istituto Nazionale di Geofisica e Vulcanologia (INGV), were considered. Satellite traces (STs) are confirmed to be a necessary precursor to the appearance of an RSF trace on the ionograms. Moreover, an analysis of isoheight contours of electron density seems to suggest a relationship between RSF occurrence and gravity wave (GW) propagation.

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